What is an Ultracapacitor?:Ultracapacitors Are

A 100-year-old technology enhanced by modern materials

Based on polarization of an electrolyte, high surface area electrodes, and extremely small charge separation

Known as Electrochemical Double Layer Capacitors and Supercapacitors

C = er A/dMinimize (d)Maximize (A)

E = 1/2 CV2

Dielectric

Film foil Electrode

Electrolyte

ECDL

Separator

What is an Ultracapacitor?:Ultracapacitors Are

Series/Parallel configurations Changes capacitor size; profiles are the same

Series configurations Capacitance decreases, Series Resistance increases

Cs=Ccell/(#of cells in series) Rs=Rcell*(# of cells in series)

Parallel configurations Capacitance increases, Series Resistance decreases

CP=Ccell*(# of cells in parallel) RP=Rcell/(# cells in parallel)

Current controlled Use output current profile to determine dV/dt

dV = I * (dt/C + ESR)

Basic Model

What is an Ultracapacitor?:Performance Characteristics

Ultracapacitors perform mid-way between conventional capacitors and electrochemical cells (batteries)

Fast charge and discharge capability

Highly reversible process, hundreds of thousands of cycles

Lower energy than a battery ~10% of battery energy

Greater energy than electrolytic capacitors

Excellent low temperature performance

Application Model

When Can I Use an Ultracapacitor?

Applications that require high reliability back-up power solutions

Short term bridge power (1 - 60 seconds) for transfer to secondary source or orderly shut down

Power quality ride-through to compensate for momentary severe voltage sags

Power buffer for large momentary in-rush or power surges

Back-Up Power Support

Ultracapacitors provide peak power…

...and back-up power.

Required Power

Available Power Ultracapacitor Backup Power

Peak Power Shaving

Ultracapacitors provide peak power...

AvailablePower

Required PowerUltracapacitor Peak Power

Available PerformanceLead Acid Battery

UltracapacitorConventional

Capacitor

Charge Time 1 to 5 hours 0.3 to 30 seconds 10-3 to 10-6 seconds

Discharge Time 0.3 to 3 hours 0.3 to 30 seconds 10-3 to 10-6 seconds

Energy (Wh/kg) 10 to 100 1 to 10 <0.1

Cycle Life 1000 >500000 >500000

Specific Power (W/kg) <1000 <10000 <100000

Charge/discharge efficiency

0.7 to 0.85 0.85 to 0.98 >0.95

Technology Comparison

0,01

0,1

1

10

100

1000

10 100 1000 10000

Power Density/[W/kg]

En

erg

y D

en

sity

/[W

h/k

g]

Double-Layer Capacitors

10h 1h0,1h

36sec

3,6sec

0,36sec

36msec

Lead Acid Battery

Ni/Cd

Li-Battery

Al-Elco

U/C

Technology ComparisonFuel Cells

Ultracapacitor World Market

Consumer Products Industrial Transportation

Car Audio

PDA

Toys

Memory Backup

Remote Monitoring

Handheld Instrumentation

Short term Back-up Power

Automation/Robotics

Hybrid Bus/Truck

Engine Starting

Light Hybrid

Local Power

Rail

Markets and Applications:Consumer Electronics

Market needs include: Miniaturization

Burst-mode transmission

Compatibility with new/divergent designs

Greater functionality due to merging of protocols

Requires smaller/more efficient devices

Burst Mode Transmission

Requires compatibility with lower voltage power supplies

Uses 1/2 voltage but requires at least 2 times current to maintain same power output

Allows for lower cost primary batteries instead of rechargeable batteries

Markets and Applications:Miniaturization

Price/performance/size improvements Allows batteries to be sized for energy requirements, not power

Allows use of alternative, less expensive chemistries

Extends device use time by up to 100%

Allows primary (non-rechargeable) batteries to be used for lower cost and convenience

Allows smaller battery size while still meeting peak power requirements

Markets and Applications:Ultracapacitor Benefits

PowerBurst Ultracapacitors:Cells

Cylindrical radial leaded devices

0.5 Farad to 100 Farad, with other values on request

2.7 Volts

Drop-in replacement to Panasonic, Ness, and others

Maxwell parts inside PC5 and PC10 cells

Active or Passive balancing

5.0 Volts to 25 Volts standard & customs

U.S. design and prototyping, Asian production.

Custom circuits and packaging available using PC or TPL cells.

PowerBurst Ultracapacitors:Modules

Ultracapacitor Aging

Unlike batteries, ultracapacitors do not have hard end-of-life criteria

Ultracapacitors degradation is apparent through a gradual loss of capacitance and a gradual increase in resistance

End of life is when the capacitance and resistance are out of the application range, and this will differ depending on the application.

Therefore, life prediction is easily done

UC Benefits Summary

Calendar life Function of average voltage and temperature

Cycle life Function of average voltage and temperature

Charge acceptance Charge as fast as discharge, limited only by heating

Temperature High temp; no thermal runaway

Low temp; -40°C

UC Benefits Summary

No fixed VOC

Control flexibility; context-dependent voltage is permitted

Power source voltage compatibility Examples: Fuel cells, photovoltaics

No Vmin

Cell can be discharged to 0 Volts

Control safety: no over-discharge

Service safety

UC Benefits Summary

Cell voltage management Only required to prevent individual cell over-voltage

State of charge and state of health State of charge equals VOC

Dynamic measurements for C and EST equals state of health

No historical data required

Inventory Management Services Warehousing and Material Management

N. America & Asia

Schedule Share, Demand Pull, Consignment, EDI

NPI facility in San Diego for quickturn custom modules.

Third Party warehousing

Customer specific programs tailored to individual needs