Hybrid Vehiclesand the Future of Personal Transportation

75349_C000.indd i75349_C000.indd i 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

75349_C000.indd ii75349_C000.indd ii 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

CRC Press is an imprint of theTaylor & Francis Group, an informa business

Boca Raton London New York

Allen Fuhs

75349_C000.indd iii75349_C000.indd iii 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

CRC PressTaylor & Francis Group6000 Broken Sound Parkway NW, Suite 300Boca Raton, FL 33487-2742

2009 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business

No claim to original U.S. Government worksPrinted in the United States of America on acid-free paper10 9 8 7 6 5 4 3 2 1

International Standard Book Number-13: 978-1-4200-7534-2 (Softcover)

This book contains information obtained from authentic and highly regarded sources Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the valid-ity of all materials or the consequences of their use. The Authors and Publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint

Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or uti-lized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopy-ing, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers.

For permission to photocopy or use material electronically from this work, please access www.copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC) 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For orga-nizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged.

Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe.

Library of Congress Cataloging-in-Publication Data

Fuhs, Allen E.Hybrid vehicles and the future of personal transportation / by Allen Fuhs.

p. cm.Includes bibliographical references and index.ISBN-13: 978-1-4200-7534-2ISBN-10: 1-4200-7534-91. Hybrid electric cars. I. Title.

TL221.15.F84 2009629.229--dc22 2008013028

Visit the Taylor & Francis Web site athttp://www.taylorandfrancis.comand the CRC Press Web site athttp://www.crcpress.com

75349_C000.indd iv75349_C000.indd iv 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

Dedication

To Maxine, my companion

through trials and triumphs

75349_C000.indd v75349_C000.indd v 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

75349_C000.indd vi75349_C000.indd vi 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

vii

ContentsPreface ..........................................................................................................................................xxxi

Chapter 1 Historical Roots of Hybrid Automobiles ......................................................................1

Ancient History: Crossroads ........................................................................................1Steam Cars ...................................................................................................................1Electric Cars .................................................................................................................2Gasoline Cars ...............................................................................................................3Carriages ......................................................................................................................4Crossroads ....................................................................................................................4Invention of Hybrid Automobile ..................................................................................4Key Features of Hybrid Automobile ............................................................................5Early Hybrid Vehicles ..................................................................................................5Woods GasElectric Car ..............................................................................................6Control Systems for Early Hybrids ..............................................................................6Modern Period of Hybrid History ................................................................................7Hybrid Automobiles: Stirring of Interest in the 1990s .................................................8

GM EV-1 Electric Car .............................................................................................8Renewed Interest in Hybrids ...................................................................................8

Partnership for a New Generation of Vehicles ........................................................... 10Crossroads 2008: Sneak Preview of the Future ......................................................... 12References .................................................................................................................. 13Additional References ................................................................................................ 14

Chapter 2 Why the Crisis? Hybrid Vehicles as a Mitigation Measure........................................ 15

Introduction ................................................................................................................ 15Story ........................................................................................................................... 16Setting the Stage ......................................................................................................... 16Depletion of Petroleum ............................................................................................... 18Estimating Oil Production .......................................................................................... 19Oil Reserves and Resources ....................................................................................... 19Demand for Petroleum ...............................................................................................20Oil in the United States .............................................................................................. 21Hubberts Peaking Theory .........................................................................................22

Swimming Pool Model ..........................................................................................22Standard Presentation of Hubberts Curves ..........................................................24New Analytical Representation .............................................................................25Variation of the Production Rate, r(t) ....................................................................26Limit of P/Q as Time Approaches Negative Infi nity ............................................27Characteristic Production Time, t .........................................................................28Finding r0 and QT ..................................................................................................29When Do Hubberts Curves Apply? ......................................................................30When Do Hubberts Curves Not Apply? ...............................................................30

Near-Term Situation ...................................................................................................30Transportable Fuels Crisis .....................................................................................30

75349_C000.indd vii75349_C000.indd vii 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

viii

Current Fleet of Low Miles per Gallon Vehicles ..................................................30Application of Increased Engine Effi ciency .......................................................... 31Vehicle Power ........................................................................................................ 32Vehicle Weight ....................................................................................................... 32Vehicle Size ........................................................................................................... 32Vehicle Powertrain ................................................................................................ 33Options and Accessories ....................................................................................... 33Posted Speed Limits .............................................................................................. 33Energy Conservation ............................................................................................. 33

Summary ....................................................................................................................34References ..................................................................................................................34

Chapter 3 Overview of Hybrid Vehicles ..................................................................................... 37

Introduction ................................................................................................................ 37Approaches to Beat the High Cost of Gasoline ..................................................... 37Saving Gasoline ..................................................................................................... 37Hybrid Performance .............................................................................................. 38Allure of Plug-In Hybrids ...................................................................................... 38Conversion or Clean Sheet Design ........................................................................ 39Conversion or Clean Sheet Design: Impact on AWD and 4WD ..................................................................................................... 39Current View on Hybrids ...................................................................................... 39Reasons to Buy a Hybrid .......................................................................................40More Playthings than You ................................................................................. 41Reasons Not to Buy a Hybrid ................................................................................ 41Diesel/Electric Hybrids ......................................................................................... 41Role of Design in Buying Decision ....................................................................... 41

Concept Hybrids and Electric Vehicles ...................................................................... 42Different Types of Concept Hybrids...................................................................... 42Audi Metroproject Quattro .................................................................................... 42BMW Connected Drive X5 Hybrid SUV.............................................................. 42BMW X6 ActiveHybrid Sport AWD Coupe ......................................................... 42Cadillac Provoq FC Hybrid ................................................................................... 42Chinese GAC A-HEV Sedan................................................................................. 43Chinese Great Wall Gwkulla Concept Electric Car .............................................. 43Chinese Plan 863 for Hybrids and Alternate Fuels ............................................... 43Chrysler Citadel ..................................................................................................... 43Chrysler Eco Voyager FCV ................................................................................... 43Citron Airscape Hybrid ....................................................................................... 43Citron4 Hybrid Sedan .......................................................................................... 43Citron C-Cactus Hybrid Sedan ............................................................................ 43Diahatsu Hybrid Vehicle Sports: Sports Car ......................................................... 43Dodge ESX3 PNGV Sedan ...................................................................................44Dodge Powerbox SUV Hybrid ..............................................................................44Dodge Zeo EV .......................................................................................................44Fisker Hybrid Luxury Sedan .................................................................................44Ford Edge with HySeries Drive .............................................................................44Ford Fiesta Hybrid .................................................................................................44Ford Focus FCV ....................................................................................................44Ford Focus HydrogenICE Conventional Vehicle ................................................44

75349_C000.indd viii75349_C000.indd viii 8/12/2008 3:22:59 PM8/12/2008 3:22:59 PM

ix

Ford Refl ex or Refl 3x ............................................................................................. 45Ford HySeries Edge: An FC/Battery Plug-In Hybrid ............................................ 45GM Chevrolet Volt (Cadillac Volt) ........................................................................ 45GM Graphyte SUV ................................................................................................46GM Precept: Product of PNGV Program ..............................................................46

GM Precept: Diesel Hybrid ..............................................................................46GM Precept: FC Version ..................................................................................46

GM Sequel .............................................................................................................46GM Ultralite: Another PNGV Supercar ................................................................ 47Honda Clarity FC Hybrid ...................................................................................... 47Honda CR-V Crossover Hybrid ............................................................................. 47Honda CR-Z Hybrid .............................................................................................. 47 Honda FC Hybrid, FCX ........................................................................................ 47Honda Hybrid Sedan ............................................................................................. 47Honda Small Hybrid Sports Concept ....................................................................48Honda Puyo FCV...................................................................................................48Hyundai i-Blue FCV ..............................................................................................48Jeep Renegade DieselElectric Hybrid .................................................................48Kia FCV ................................................................................................................48Land Rover LRX SUV ..........................................................................................48Land Rover E SUV ............................................................................................48Range Rover Hybrid ..............................................................................................48Lexus LF-Xh ..........................................................................................................48Loremo Diesel 2 + 2 Subcompact ......................................................................... 49Loremo Diesel GT Subcompact ............................................................................ 49Mazda Premacy Hydrogen RE Hybrid .................................................................. 49Mazda Senku HEV Sports Car .............................................................................. 49Mercedes Benz C-Class ........................................................................................ 49Mercedes Benz F-Class HCCI Hybrid .................................................................. 49Mercedes Benz S-Class Bluetec Hybrid................................................................ 49Mercedes Benz S-Class Direct Hybrid .................................................................50Mercedes Benz Vision Grand Sports Tourer Hybrid ............................................50Mercury Meta One Crossover ...............................................................................50Mitsubishi Concept CT MIEV Hybrid ..................................................................50Mitsubishi Pure EV ...............................................................................................50Mitsubishi iMiEV Sport Pure EV .........................................................................50Nissan Mixim EV .................................................................................................. 51Nissan Pivo 2 ......................................................................................................... 51Nissan Tino Hybrid Sedan .................................................................................... 51Opel (GM) Astra Diesel Electric ........................................................................... 51Opel Corsa Hybrid ................................................................................................. 51Opel Flextreme ...................................................................................................... 51Peugeot 307 Hybrid Sedan .................................................................................... 51Phoenix Electric Sport Utility Truck ..................................................................... 51Porsche Panamera Sports Sedan Hybrid ............................................................... 52Saturn Vue Green Line Plug-In Hybrid ................................................................. 52Subaru B5-TPH Two-Seat GT ............................................................................... 52Subaru G4e ............................................................................................................ 52Subaru R1e............................................................................................................. 52Suzuki Kizashi 2 ................................................................................................... 52Suzuki Twin-Turbo ................................................................................................ 52

75349_C000.indd ix75349_C000.indd ix 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

x

Tesla Electric Sports Car ....................................................................................... 52Tesla Motors Blue Star Economy EV .................................................................... 53Tesla Motors White Star Luxury EV .................................................................... 53Toyota 1/X Plug-In Hybrid .................................................................................... 53Toyota A-BAT Hybrid Pickup ............................................................................... 53Toyota FT-HS Sports Car Hybrid ..........................................................................54Toyota Hi-CT Plug-In Hybrid ................................................................................54Toyota Hybrid X ....................................................................................................54Volkswagen Pure Diesel Ecoracer .....................................................................54Volkswagen Space Up! Blue FC Hybrids ..............................................................54Volkswagen Up! and Space Up! Plug-In Hybrids ..................................................54Volvo 3CC .............................................................................................................54Volvo ReCharge ..................................................................................................... 55

Concept Hybrids on Two (or Three) Wheels .............................................................. 55Suzuki Crosscage FC Motorcycle ......................................................................... 55Twike ..................................................................................................................... 55Vectrix Electric Maxi-Scooter .............................................................................. 55Yamaha Luxair Motorcycle Hybrid ....................................................................... 55

Park the Car ................................................................................................................ 55Intercity Congestion Forces Trend ........................................................................ 55

Description of a Few Select Hybrids .......................................................................... 56Chevrolet Tahoe SUV 2008 and GMC Yukon SUV 2008: Full Dual-Mode Hybrid ......................................................................................... 56Ford Escape SUV .................................................................................................. 56GM Chevrolet Malibu Mild Hybrid ...................................................................... 58GM Saturn VUE Green Line Mild Hybrid SUV .................................................. 58Honda Civic Hybrid 2006...................................................................................... 58Honda Accord Hybrid 2007 .................................................................................. 59Toyota Highlander SUV/Lexus RX 400 h ............................................................. 59Toyota Prius I Hybrid Sedan .................................................................................60Toyota Prius II Hybrid Sedan ................................................................................60Discussion of Prius Confi guration .........................................................................60Chevrolet Silverado Mild Hybrid Pickup .............................................................. 62Toyota 2007 Camry Hybrid Sedan ........................................................................ 63Mass to Power Ratio .............................................................................................. 63

Hybrid Truck and Bus Technology ............................................................................64Economics of Bus and Truck .................................................................................64Comparison Lifetimes or Cycles of Operation ......................................................64Attractiveness of Supercapacitor for Trucks and Buses ........................................64Duty Cycle and Application of Hybrid ..................................................................65Emissions ...............................................................................................................65Future for Diesel/Electric Heavy-Duty Hybrids ...................................................65Organizations Considering Hybrid Trucks ............................................................65Truck Original Equipment Manufacturers Working on Hybrids ..........................65

Concept and Production Hybrid Trucks .....................................................................65FedEx Hybrid Delivery Truck ...............................................................................65GM/Chrysler Hybrid Light Trucks ........................................................................66Diahatsu Hybrid Small Light Delivery Truck .......................................................66Ford Hytrans Light Commercial Vehicle ..............................................................66Dodge Sprinter Plug-In Hybrid Van ......................................................................66Kalmar Hybrid Terminal Tractors .........................................................................66Nissan Condor Medium-Size Hybrid Truck ..........................................................66

75349_C000.indd x75349_C000.indd x 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xi

Hydrogen Electric Racing Federation ........................................................................66Production Hybrid Buses ............................................................................................ 67

Gillig-GMC Hybrid Bus ........................................................................................ 67Mercedes Benz Hybrid Bus ................................................................................... 67Mitsubishi Aerostar Hybrid Bus ............................................................................ 67Orion VII Hybrid Bus (BAE Systems) ..................................................................68

Military Applications of Hybrids ...............................................................................68Hybrids and Military Interest ................................................................................68DARPA Advanced (Military) Vehicle ...................................................................68Shadow: A Reconnaissance, Surveillance, and Tracking Vehicle ........................68

Parting Perspective .....................................................................................................68Alternate Vehicles .................................................................................................68

Summary ....................................................................................................................69Appendix 3.1 .............................................................................................................. 70References .................................................................................................................. 70

Chapter 4 Hybrid Automobile: What Is It? ................................................................................. 73

Hybrid Defi nition ....................................................................................................... 73New Idea for a Hybrid ................................................................................................ 73Hybrid Electric Vehicle .............................................................................................. 73Inherently More Expensive ........................................................................................ 75Hybrids: Mainstream or on the Fringe? Success or Failure? ..................................... 75HEV Propulsion Design Options ............................................................................... 76HEV Propulsion Design Options: Series ................................................................... 76Discussion of Various Operating Modes: Series ........................................................ 78HEV Propulsion Design Options: Parallel ................................................................. 78Discussion of Various Operating Modes: Parallel .....................................................80Comment on Toyota Prius .......................................................................................... 81Choice of Series, Parallel, or Mixed .......................................................................... 81Technologies for a Successful Hybrid ........................................................................ 81Operation with a Dead Battery ............................................................................... 81Summary .................................................................................................................... 82

Chapter 5 Why Hybrids Get Good Mileage ............................................................................... 83

Introduction ................................................................................................................ 83Hybrid Specifi c ........................................................................................................... 83

Heavy Hitters Lineup ............................................................................................ 83Regenerative Braking ....................................................................................... 83Engine Downsizing ...........................................................................................84Electrical-Only: Motor Assist ...........................................................................86Electrical-Only: Plug-In Hybrid Fuel Economy ...............................................86

Nickel and Dime Improvements ............................................................................87Engine Idle-Off: StartStop .............................................................................87Automobile Auxiliary Components..................................................................87Special Focus on Air-Conditioning ..................................................................88Tripled Savings by Shifting the Auxiliary Load ..............................................88Damping Driveline Oscillations and Shudders ................................................ 89Vehicle Launch ................................................................................................. 89

Common with CVs ................................................................................................ 89Also-Ran ........................................................................................................... 89

75349_C000.indd xi75349_C000.indd xi 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xii

Electrical Power Steering .................................................................................90Fast Warm-Up ...................................................................................................90Aerodynamics ...................................................................................................90Rolling Resistance of Tires ............................................................................... 91Vehicle Weight ..................................................................................................92Engine Effi ciency ..............................................................................................92Powertrain .........................................................................................................92Improved Lubricants: Friction and Wear ..........................................................93Improved Fuels .................................................................................................93Range and Miles per Gallon: Cruise Mode ......................................................93Hybrid: Pure Electric Mode ..............................................................................95Hybrid: All Power through the Battery ............................................................96Hybrid: Bypass the Battery ...............................................................................96Conclusions from the Three Different System Designs ...................................97

Summary ....................................................................................................................97References ..................................................................................................................98

Chapter 6 Multifaceted Complexity of Batteries ........................................................................99

Introduction ................................................................................................................99Brief Overview of the Three Electrochemical Devices ........................................99Function of the Battery or Capacitor ................................................................... 100Function of an FC ................................................................................................ 100

Electrical Defi nitions for Hybrid Vehicles ............................................................... 100Battery and Electrical Defi nitions ....................................................................... 100Battery Capacity .................................................................................................. 102Battery Properties Used to Assess Performance ................................................. 102Importance of Energy Density and Specifi c Energy ........................................... 103Energy Density or Energy Density? .................................................................... 103

Battery Electrochemistry ......................................................................................... 104Electrochemistry of Cells .................................................................................... 104Electrochemistry of Eels ..................................................................................... 105Computational Electrochemistry ......................................................................... 105Discharge Characteristics .................................................................................... 105Temperature Sensitivity ....................................................................................... 106Self-Discharge ..................................................................................................... 106Performance Boundaries in a Hybrid or Electrical Vehicle ................................ 106Battery Peculiarities ............................................................................................ 107

Battery Peculiarities: NiMH Battery Voltage Depression with Memory Effect ........................................................................................ 107Battery Peculiarities: Voltage Recovery ......................................................... 107

Polarization .......................................................................................................... 108Number of Different Possible Cells: Different Cell Chemistries ........................ 108Battery Design ..................................................................................................... 108

Battery Life .............................................................................................................. 110What Is Battery Failure? ...................................................................................... 110State of Charge: Restrictions and Battery Utilization ......................................... 110Determining Actual SOC and Battery Aging ..................................................... 111

Determining Actual SOC: Lead Acid Battery ............................................... 111Determining Actual SOC: NiMH Battery ...................................................... 111

Battery Charging and Discharging .......................................................................... 112

75349_C000.indd xii75349_C000.indd xii 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xiii

Charging Rate ...................................................................................................... 112Discharging Rate ................................................................................................. 113Thermal Runaway ............................................................................................... 113

Battery Data ............................................................................................................. 113Lead Acid Battery ............................................................................................... 113Nickel Metal Hydride Battery ............................................................................. 114Lithium-Ion Battery ............................................................................................. 115

Lithium-Ion Battery for HEV ......................................................................... 115Safety ........................................................................................................................ 115Cost ........................................................................................................................... 115Calendar Life ............................................................................................................ 116

Guide to Long Battery Life ................................................................................. 116Electrochemistry ...................................................................................................... 116

Lithium-Ion Battery ............................................................................................. 116Liquid/Gel Electrolyte ......................................................................................... 116Solid Electrolyte Interphase ................................................................................ 117Temperature Limits ............................................................................................. 117Charge/Discharge Cycle ...................................................................................... 117

Lithium-Ion Alkaline Battery .................................................................................. 117Advantages .......................................................................................................... 117Disadvantages ...................................................................................................... 118

Lithium-Ion Polymer Battery ................................................................................... 118Advantages .......................................................................................................... 118Disadvantages ...................................................................................................... 119

Advanced Technology .............................................................................................. 119Nanostructure ...................................................................................................... 119Application of Nanotechnology ........................................................................... 119Advanced Anodes (Negative Electrode upon Discharge) ................................... 119Advanced Cathodes (Positive Electrode upon Discharge) .................................. 120Advanced Electrolytes ......................................................................................... 120Battery Management System ............................................................................... 120

Application of Lithium-Ion Battery in Hybrids ....................................................... 120Application of Li-Ion Battery .............................................................................. 120

Application of Batteries in Hybrid and Electric Vehicles ........................................ 122Batteries in Spacecraft......................................................................................... 122Prius I Battery...................................................................................................... 122Nissan Battery ..................................................................................................... 123Application of Li-Ion Battery: Two Approaches ................................................. 123Application of Li-Ion Battery: Mitsubishi Pure EV ............................................ 123Application of Li-Ion Battery: Nissan and NEC ................................................. 123Interchangeable Power Packs .............................................................................. 123Comparisons for Different Energy Storage Devices ...........................................124

Battery Selection ......................................................................................................124Direct Effect on Miles per Gallon .......................................................................124Customer Satisfaction ..........................................................................................124Safety ...................................................................................................................124Hybrid Cost on the Showroom Floor .................................................................. 125Permissible Operating Environment ................................................................... 125Avoiding Unanticipated Recalls .......................................................................... 125Recycling Batteries .............................................................................................. 125Cost of Battery ..................................................................................................... 126

75349_C000.indd xiii75349_C000.indd xiii 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xiv

Battery Properties..................................................................................................... 126Battery Safety ...................................................................................................... 126Battery Effi ciency and Internal Impedance of Battery ....................................... 126Monitoring Individual Cells ................................................................................ 127Thermal Management ......................................................................................... 127

Hybrids Using Electrochemical Storage .................................................................. 127FC/Electrochemical Capacitor Hybrid ................................................................ 128Battery Electrochemical Capacitor Hybrid ......................................................... 128Tribrid, the Three-Way Hybrid: Fuel Cell, Hydrogen ICE, and Battery Hybrid ...................................................................................... 129

Maps Based on Battery Energy and Power .............................................................. 130Relation of Battery to Overall Hybrid ................................................................. 130Plug-In EV or EV: Adequate Power, Large Energy ............................................ 131HEV: High Peak Power, Small Energy ............................................................... 132

Fuel Cells .................................................................................................................. 132Fuel Cell: Electrochemistry ................................................................................. 132Fuel Cell: Types ................................................................................................... 134Fuel Cell: Characteristics .................................................................................... 135Fuel Cell: Effi ciency ............................................................................................ 135Fuel Cell: Applications ........................................................................................ 135Fuel Cell: Hybridness .......................................................................................... 138Hydrogen Production ........................................................................................... 138Reforming: Hydrogen Production ....................................................................... 138

Capacitors ................................................................................................................. 139Electrolytic Capacitors (SCs) ............................................................................... 139Features of SCs .................................................................................................... 140Charge/Discharge Effi ciency ............................................................................... 140Characteristic Time Constant .............................................................................. 141Energy Stored ...................................................................................................... 141Comparison Lifetimes or Cycles of Operation .................................................... 142Attractiveness of SC for Trucks and Buses ......................................................... 142Some Analogies ................................................................................................... 142

Summary .................................................................................................................. 143Appendix 6.1: Electrochemistry of a Voltaic Cell and Fuel Cell ............................. 144Introduction .............................................................................................................. 144Components of a Cell ............................................................................................... 144

Voltage Distribution in Cell and External to Cell ............................................... 146Electrolysis ............................................................................................................... 147Electrochemical Potential ........................................................................................ 148Electrochemistry of Cell (Battery) ........................................................................... 149

Lead Acid Battery ............................................................................................... 149Voltage and Power from a Cell ............................................................................ 151

Electrochemistry of FC ............................................................................................ 151Hydrogen/Oxygen FC .......................................................................................... 151

Appendix 6.2: Capacitors ......................................................................................... 154References ................................................................................................................ 154

Chapter 7 Obesity: Bad in Humans, Bad in Cars ..................................................................... 157

Introduction .............................................................................................................. 157Vehicle Weight and Fuel Economy .......................................................................... 157

75349_C000.indd xiv75349_C000.indd xiv 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xv

First Passing Comment ........................................................................................ 157Second Passing Comment ................................................................................... 158How to Improve Fuel Economy? ......................................................................... 158How to Decrease Vehicle Weight? ...................................................................... 158Interplay: Production Lines and Vehicle Design ................................................. 159Weight Factors Affecting Fuel Economy ............................................................ 159Power and Fuel Consumption .............................................................................. 159Rolling Resistance due Mainly to Tires .............................................................. 160Power to Climb Grades ....................................................................................... 160Power for Acceleration ........................................................................................ 160Correlation between Acceleration and Fuel Economy ........................................ 161Correlation between Weight and Fuel Consumption at Cruise ........................... 161Fuel Economy for Cars, Trucks, and Both .......................................................... 162Weight and Performance ..................................................................................... 163Engine Effi ciency Improvement to Match Weight Gain ..................................... 165

Vehicle Weight and Vehicle Safety .......................................................................... 165Weight Reduction and Vehicle Safety ................................................................. 165Seeming Paradox ................................................................................................. 168Added Comments on Acceleration ...................................................................... 168Acceleration Based on Crumple Zones and Driver Motion ................................ 168Fractional Form for Acceleration Based on Crumple Zones and Driver Motion ............................................................................................... 170Velocities Relative to the CG ............................................................................... 171Compensation for the Double Acceleration ......................................................... 172Compensation for Realistic Weight Disparity ..................................................... 172NHTSA Action .................................................................................................... 173Weight Disparity .................................................................................................. 174Effect of Footprint on Safety ............................................................................... 174CO2 Emissions versus Vehicle Weight ................................................................ 175

Summary .................................................................................................................. 176Appendix 7.1: Mathematics of Fractional Change ................................................... 176Appendix 7.2: Derivation of Equation 7.12 .............................................................. 177References ................................................................................................................ 178

Chapter 8 Vital Role of the Control System ............................................................................. 181

History of Automobile Control ................................................................................ 181Example of Engine Controls from 1980s ................................................................. 181Function of Control System ...................................................................................... 182Analogy with Symphony Orchestra Conductor ....................................................... 182Fringe Benefi ts of Control System ........................................................................... 182Simulation and Modeling ......................................................................................... 182Design Sequence ...................................................................................................... 183Algorithm Development ........................................................................................... 183Confl ict: Fuel Economy and Exhaust Emissions ..................................................... 184Exhaust Emissions: Origin of Pollutants .................................................................. 184Various Operational Modes to Be Controlled .......................................................... 184Elements of Control Theory ..................................................................................... 186Overview of Control System: Cartoon Version ........................................................ 187Overview of Control System: ECU Version ............................................................. 189Descriptions of ECUs ............................................................................................... 189

75349_C000.indd xv75349_C000.indd xv 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xvi

Hybrid ECU ......................................................................................................... 189Engine ECU ......................................................................................................... 190M/G ECU ............................................................................................................ 190CVT ECU ............................................................................................................ 190Power Electronics ECU ....................................................................................... 190Battery ECU or Battery Management System .................................................... 190Air-Conditioning ECU ........................................................................................ 190

Control Area Network .............................................................................................. 190Control Variables: Variables Connecting the ECUs ................................................ 191Engine Management ................................................................................................. 191Exhaust Gas Recirculation ....................................................................................... 192Engine Effi ciency Map ............................................................................................. 192Load Leveling........................................................................................................... 193Control Complexity and Diffi culty .......................................................................... 193Adaptive Control Strategy ........................................................................................ 194Robustness of Control System .................................................................................. 194Four Control Strategies ............................................................................................ 194Rules-Based Control Algorithm ............................................................................... 195Optimization............................................................................................................. 195Hardware-Constrained Optimization ....................................................................... 197Fuzzy Logic Control: What Is It? ............................................................................. 197Fuzzy Logic Control Application to Hybrid Control ............................................... 197Neural Network Control: What Is It? ....................................................................... 198NN Control: Application to Hybrid Control ............................................................ 198Comparison of Fuzzy Logic and NNs for Control ................................................... 199Combined Fuzzy Logic and NNs for Control .......................................................... 199Electrical Components: Electrical Motors and Generators ......................................200Summary ..................................................................................................................200References ................................................................................................................200

Chapter 9 Regenerative Braking ............................................................................................... 201

Introduction .............................................................................................................. 201Function of Regenerative Braking ....................................................................... 201Integration of Functions and Components .......................................................... 201Logic Relative to Size of Regenerative Brakes ................................................... 201

Brake Cooling, Aerodynamic Drag, and Regenerative Braking .................... 201Brakes and Tires Primer...........................................................................................202

Why Discuss Tires? .............................................................................................202Slip, Slide, and Skid.............................................................................................202Relation between Tire Force and Weight on Tire ................................................203Weight on Each Wheel ........................................................................................203Braking Dive: Shift of Weight to Front Tires ..................................................204Tire Patch .............................................................................................................205Longitudinal Tire Forces .....................................................................................205

Longitudinal Tire Forces: Traction .................................................................205Longitudinal Tire Forces: Braking .................................................................206

Locked Wheels ....................................................................................................207Lateral Tire Forces ..............................................................................................207Directional Stability ............................................................................................207Antilock Brake System ........................................................................................208Regenerative Coasting .....................................................................................208

75349_C000.indd xvi75349_C000.indd xvi 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xvii

Energy to Be Recovered by Regenerative Braking .............................................208Bands of SOC for Battery ....................................................................................209Stopping Distance ................................................................................................ 210Time and Stopping Distance: Friction Brakes .................................................... 212Time and Stopping Distance: Regenerative Brakes ............................................ 212Effi ciency of Regenerative Braking ..................................................................... 214Typical Driving Cycle.......................................................................................... 214Braking Force from Electrical Generator............................................................ 215Two Design Approaches for Regenerative Braking ............................................ 216Regenerative Braking Integrated with Conventional Hydraulic System ............. 216

Driver Input .............................................................................................................. 217Brake Actuator ......................................................................................................... 217Three-Port Switch .................................................................................................... 217Controller: Inputs ..................................................................................................... 218Controller: Outputs ................................................................................................... 218M/G: Generator Mode .............................................................................................. 218Summary .................................................................................................................. 218Appendix 9.1: Equations for Regenerative and Friction Brakes .............................. 219Regenerative Brakes ................................................................................................. 219Friction Brakes .........................................................................................................220References ................................................................................................................ 221

Chapter 10 Narrow Operating Band for Gasoline Engine .......................................................... 223

Introduction .............................................................................................................. 223Demands of Driving Cycle .................................................................................. 223

Driving Cycle ........................................................................................................... 223Roads ................................................................................................................... 223Intensity of Traffi c ...............................................................................................224Terrain .................................................................................................................224Road Quality ........................................................................................................224Weather ................................................................................................................225Mission of Vehicle: Widespread Usage ...............................................................225Mission of Vehicle: Specialty ..............................................................................225Real-World Data ..................................................................................................225Variables for Driving Cycle .................................................................................226

Minimum Fuel Consumption Line ...........................................................................226Engine Map .........................................................................................................226Superimpose Engine Power Contours .................................................................226Basic Operating Line: Minimum Fuel Consumption Line.................................. 227Narrow Operating Band for Gasoline Engine .....................................................228Matching the Wheels to the Engine .................................................................... 229Effect of Number of Transmission Speeds on Fuel Economy.............................230Effect of Number of Transmission Speeds on Control of Engine Speed ............230Role of Electric Motor in a Hybrid ...................................................................... 231

Summary .................................................................................................................. 231References ................................................................................................................ 232

Chapter 11 Hybridness: A Basic Design Decision ...................................................................... 233

Defi nition of Hybridness .......................................................................................... 233Story ......................................................................................................................... 233

75349_C000.indd xvii75349_C000.indd xvii 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xviii

Hybrid Design Philosophy .......................................................................................234Hybridness: Parallel Hybrid .....................................................................................234Hybridness: Series, Mixed, and Range Extender (Plug-In) Hybrids ........................ 235Range Extender ........................................................................................................ 236Optimization and Hybridness .................................................................................. 237Battery Power and Electric Motor Power ................................................................. 237Residual Performance with a Dead Battery ......................................................... 238Effect of Low Charge ............................................................................................... 239Power-to-Weight Ratio ............................................................................................. 239Interpretation of Ramps ........................................................................................... 239Various Techniques to Enhance Hybrid Performance .............................................240

StartStop ............................................................................................................ 241Damping Driveline Oscillations .......................................................................... 241Vehicle Launch .................................................................................................... 241Regenerative Braking .......................................................................................... 241Motor Assist ........................................................................................................ 241Electric-Only Propulsion ..................................................................................... 241Downsize the Engine ...........................................................................................242Miles per Gallon Gain .........................................................................................242

Mild or Micro Hybrid Features ................................................................................242Why Is H About 50% a Good Spot for High Miles per Gallon? ..............................242Plug-In Hybrid ..........................................................................................................242All-Wheel Drive Hybrid ........................................................................................... 243Summary ..................................................................................................................245Appendix 11.1: Derivation of Range Extension Equations ......................................245Appendix 11.2: Range of a Plug-In Hybrid .............................................................. 247Reference .................................................................................................................. 247

Chapter 12 Mileage Ratings .......................................................................................................249

Introduction ..............................................................................................................249Mileage Ratings .......................................................................................................249

Introduction .........................................................................................................249Little History .......................................................................................................250

Previous EPA Mileage Estimates ............................................................................. 252What Changes and What Does Not Change? ...................................................... 252Facts Concerning Mileage Ratings ..................................................................... 252Driving Cycles ..................................................................................................... 252Standardized Test Procedures ............................................................................. 253Vehicles Exempt from EPA Mileage Sticker ....................................................... 253Mileage Shortfall .................................................................................................254Consequences of Mileage Shortfall .....................................................................254Effective $/Gal due to Shortfall ........................................................................... 255

Defi ciencies in Old and New EPA Methods ............................................................. 255Revised Tests and Standards ............................................................................... 255Effects of Ambient Temperature .........................................................................256Testing Four-Wheel Drive ...................................................................................256Rolling Friction ...................................................................................................256Aerodynamic Drag ..............................................................................................256Vehicle Load ........................................................................................................256Aggressive Driving .............................................................................................. 257Driving Cycle ...................................................................................................... 257

75349_C000.indd xviii75349_C000.indd xviii 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xix

A/C and Auxiliaries ............................................................................................ 257Terrain, Curves, and Altitude .............................................................................. 258Weather ................................................................................................................ 258

New EPA Tests to Estimate Mileage ........................................................................ 258Five-Cycle Estimate: EPA-Weighted Combination of Tests ................................ 258Importance of Weighting Factors ........................................................................260Change in Vocabulary: City and Highway ..........................................................260Transition Period: 20082010 ............................................................................. 261

Testing Hybrids ........................................................................................................ 261Hybrids and the New EPA Tests to Estimate Fuel Economy .............................. 261Hybrid Modes of Operation ................................................................................. 261Driving Technique ............................................................................................... 261Regenerative Braking .......................................................................................... 261Battery State of Charge ....................................................................................... 261Hybrids, Braking, and the Panic Stop ................................................................. 262

Corporate Average Fuel Economy ........................................................................... 262Introduction ......................................................................................................... 262Marked Inconsistency .......................................................................................... 263Defi nitions for Passenger Cars and Trucks ......................................................... 263Passenger Car Standards .....................................................................................264Truck Standards: Unreformed System ................................................................264Truck Standards: Reformed System ....................................................................264Penalties for Failure to Meet CAFE Standards ...................................................265CAFE Credits ......................................................................................................265Import Fleets .......................................................................................................265Special Rules for Alternate Fuel Vehicles ...........................................................265CAFE Exempt Vehicles .......................................................................................265National Academies National Research Council Recommendations ................265CAFE and Hybrid Technology ............................................................................266Gendral Motors View on 35 mpg CAFE Standard .............................................266

How to Improve Fuel Economy: Tips for Better Miles/Gallon ................................266Debunking Tips for Better mpg: What Is a Myth? ..............................................266Negative Miles/Gallon ......................................................................................... 267Overview of Analysis .......................................................................................... 267Fractional Change in Brake-Specifi c Fuel Consumption, B ............................... 267Conventional Vehicle ...........................................................................................268Hybrid Vehicle .....................................................................................................268Driving Techniques .............................................................................................268

Preliminaries ............................................................................................................268Engine Break-In ...................................................................................................268Statistical Variations in Vehicles .........................................................................268Most Effi cient Engine Operating Point ...............................................................268

Buying Gasoline .......................................................................................................269Buy Gas in the Cool of the Morning ...................................................................269Buy When Tank Is One-Fourth Full ................................................................... 270Do Not Overfi ll Tank ........................................................................................... 270Do Not Buy Premium Fuel .................................................................................. 270Different Brands of Gasoline .............................................................................. 270Different Brands of Gasoline: Ethanol E85......................................................... 271Credit Card Rebate .............................................................................................. 271How Far to Drive to Save a Penny? ..................................................................... 271

Test Accuracy ........................................................................................................... 271

75349_C000.indd xix75349_C000.indd xix 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xx

How Much Gasoline Is Used for a Test? ............................................................. 272EPA Tests ............................................................................................................. 272EPA: Appropriate Implied Accuracy .................................................................. 272

Plan Ahead ............................................................................................................... 272Avoid Unneeded Miles ........................................................................................ 272

Drive a Quarter Mile Down the Road ............................................................ 272Just Do Not Drive ........................................................................................... 272Alternate Transportation ................................................................................. 273Combine Trips ................................................................................................ 273Rush-Hour Traffi c ........................................................................................... 273Parking ............................................................................................................ 273Know Where You Are Going ......................................................................... 273

Vehicle Maintenance ................................................................................................ 273Keep a Mileage Log ............................................................................................ 273Check Engine Light ............................................................................................. 273Tune-Up ............................................................................................................... 274Engine Oil Viscosity............................................................................................ 274Plugged Air Filter ................................................................................................ 274Wheel Alignment ................................................................................................ 275Wheel Balance ..................................................................................................... 275Tire Infl ation ........................................................................................................ 275Change in Tire Pressure with Temperature ......................................................... 276Tire Purchase and Construction .......................................................................... 276Tire Purchase and Construction: Speed Rating .................................................. 277Rolling Friction Coeffi cient: Other Factors: Temperature .................................. 277Rolling Friction Coeffi cient: Other Factors: Aspect Ratio .................................. 278Rolling Friction Coeffi cient: Other Factors: Vehicle Velocity ................................................................................................... 279Snow Tires ........................................................................................................... 279Aerodynamic Drag: Wheel Wells, Hubcaps, and Wheels ................................... 279

Getting Better mpg Cruising along the Interstate .................................................... 279Introduction ......................................................................................................... 279Cruise Control .....................................................................................................280Story: Optimum Speed ........................................................................................280Optimum Cruise Speed .......................................................................................280Resistance to Vehicle Motion: Crossover Velocity .............................................. 282Speeding: In Cruise Condition ............................................................................284Tailgating: Behind a Truck on Interstate .............................................................284Tailgating: Analysis .............................................................................................284Tailgating: Good and Bad ....................................................................................285

Aggressive Driving ...................................................................................................285Fuel Economy Meter (Instantaneous mpg) .........................................................285Aggressive Driving: Defi nition ...........................................................................285Aggressive Driving versus Gentle Driving .........................................................285Aggressive Driving: Rapid Acceleration .............................................................285Aggressive Driving: Rapid Acceleration: Neglecting Aerodynamic Drag ............................................................................287Another Quote .....................................................................................................288Reconcile Fuel Economy Meter (Instantaneous mpg) and Previous Conclusions ....................................................................................288Yet Another Quote ...............................................................................................288Aggressive Braking: Braking Hard .....................................................................288

75349_C000.indd xx75349_C000.indd xx 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xxi

Speeding: In Acceleration ................................................................................... 289Virtual Test Track ................................................................................................ 291

Driving Tips .............................................................................................................292Overdrive and Higher Gears with Manual Transmission....................................292Aerodynamic Drag: Pickup Truck Tailgate ......................................................... 293Aerodynamic Drag: Sunroof ............................................................................... 293Aerodynamic Drag: Deformation of Convertible Tops ....................................... 293Aerodynamic Drag: Roof Rack ........................................................................... 293Brake Drag .......................................................................................................... 293Reduce Use of Brakes ..........................................................................................294Idling ...................................................................................................................294Idling: Engine-Off in Conventional Vehicle .......................................................294Idling: Engine-Off in Hybrid Vehicle .................................................................294Power-Hungry Accessories and Auxiliaries ........................................................294Two-Wheel and Four-Wheel Drive ......................................................................294Extra Weight in Vehicle ....................................................................................... 295Anticipate Traffi c Conditions .............................................................................. 295Anticipate Red Lights ..........................................................................................296Towing a Trailer ..................................................................................................296Never Rev-Up the Engine ................................................................................297

Air-Conditioning and Windows Down ....................................................................297Air-Conditioning: Background ............................................................................297Air-Conditioning: Effects of Humidity ............................................................... 298Air-Conditioning: Control ................................................................................... 298Air-Conditioning: Zone and Recirculation ......................................................... 298Air-Conditioning: Thermostat Control ................................................................ 298Air-Conditioning: Cold Modulated with Heat ....................................................299Air-Conditioning: Pure Cold ...............................................................................299Air-Conditioning: Reported Losses ....................................................................299Air-Conditioning: Equation for Loss of Fuel Economy due to A/C ...................299Air-Conditioning: Sample Calculations for Fuel Economy Loss ........................300Air-Conditioning: 2005 Cadillac STS ................................................................. 301

Open Windows ......................................................................................................... 301Open Window (Sunroof) Ventilation: Comments ............................................... 301Open Window Ventilation: Loss of Fuel Economy ............................................. 301A/C versus Open Windows .................................................................................302A/C versus Open Windows: Sample Calculations ..............................................302Analytical Result for VE .......................................................................................303

Where You Drive ......................................................................................................303Headwind and Tailwind.......................................................................................303Warming Up the Engine ......................................................................................304Cold and Hot Weather .........................................................................................304Curves in Road ....................................................................................................304Ice and Snow........................................................................................................306High Altitude .......................................................................................................306Terrain: Climbing Hills .......................................................................................306Dirt and Gravel Roads .........................................................................................307Snow and Water Puddles on Road .......................................................................307Rough and Undulating Roads ..............................................................................307

Mileage Scams .........................................................................................................307Mileage Scams: Detecting Scams .......................................................................307Mileage Scams: Consequences of Using Scam Device .......................................308

75349_C000.indd xxi75349_C000.indd xxi 8/12/2008 3:23:00 PM8/12/2008 3:23:00 PM

xxii

Mileage Scams: EPA Tests ..................................................................................308Mileage Scams: A Perspective ............................................................................308Mileage Scams: Unsubstantiated Calculations....................................................309

Summary ..................................................................................................................309Appendix 12.1: Optimum Cruise Speed ..................................................................309Appendix 12.2: CAFE Fleet Average Fuel Economy and Vehicle Average ................................................................................................. 312

Fleet Average Fuel Economy ............................................................................... 312Vehicle Average ................................................................................................... 313

Appendix 12.3: Change in Fuel Economy EPA Estimates: Old versus New Test Methods .................................................................................. 313References ................................................................................................................ 314

Chapter 13 Enhancing the Sales Brochure ................................................................................. 317

Introduction .....................................................................................................