battery-notes.docx

7/29/2019 Battery-Notes.docx

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ELECTRIC CARS AND BATTERY STORAGE

Tomado de:www.evtv.me

http://blog.evtv.me/2009/05/electric-magic-its-all-about-efficiency-2/

The problem with electric cars is that batteries are not nearly as good at storing energy as

gasoline is. With 475 lbs of the very latest Lithium Ion Iron Phosphate batteries, comprising 64

cells of 3.6 fully charged volts and 90 amp hours each, I can store about 20.736 kWh of electrical

energy. Worse, I can't really use all of it. I can only use about 80% of that (16.588 kWh) before I

begin to damage the batteries.

Worse, there are some losses in putting the electricity into the batteries. I use an advanced power

factor charger that is about 95% efficient. So I have to use about 17.461 kWh of electricity from

the wall to replace that 16.588 kWh of electricity.

That's the discouraging equivalent of about 0.5 gallons of gasoline. Yes, the entire range of my car

is based on its ability to store the usable energy in one half of a gallon of gasoline.

The good news is that it uses an average of 225 wH of electricity per mile from the batteries, or

236 wH of electricity from the wall per mile. That's right I get over 4 miles per kWhr.

So let's compare:

Internal combustion car to be developed in 2011 = 1200 wH per mile.

Electric car built by whiskey drinker in garage in 2008 = 236 wH per mile.

Any way you cut it, the electric car is over five times as efficient as the internal combustion engine

automobile. Cost per mile?

1 gallon = $2.00 = 27.3 mpg = 7.32 cents per mile.

1 kWh = $0.082 = 4.24 miles = 1.93 cents per mile.

If you drive the national average of 40 miles per day:

1 day = $2.93 in gasoline or $0.77 for electricity

1 week = $20.51 gasoline or $5.39 for electricity

1 month = $87.90 gasoline or $23.10 for electricity

And that's using a mythical gasoline car that hasn't been manufactured yet, as mandated by a

government that doesn't know anything about making cars.

I don't know anything about making cars either. But you can see the video of mine running.
http://www.evtv.me/http://www.evtv.me/http://www.evtv.me/http://blog.evtv.me/2009/05/electric-magic-its-all-about-efficiency-2/http://blog.evtv.me/2009/05/electric-magic-its-all-about-efficiency-2/http://blog.evtv.me/2009/05/electric-magic-its-all-about-efficiency-2/http://www.evtv.me/


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ALL benefits from electric cars have their basis in this matter of effiiency. Electric drive plants in

cars are simply more technically elegant, and MUCH more efficient than internal combustion

engines, coal fired engines, wood fired engines, and all other known technologies.

When I step on the accelerator of my Porsche eSpeedster, it makes a sound a bit reminiscent of

the Warp Drive sound on Star Trek as the Enterprise accelerated through space.

When I step on the accelerator of my Escalade, it sounds a lot like Uncle Jedd's truck in The

Beverly Hillbillies.

Whose show do you want to be on?

Example:

With 475 lbs of the very latest Lithium Ion Iron Phosphate batteries, comprising 64 cells of 3.6 fully

charged volts and 90 amp hours each, I can store about 20.736 kWh of electrical energy. Worse, I

can't really use all of it. I can only use about 80% of that (16.588 kWh) before I begin to damage

the batteries.

Worse, there are some losses in putting the electricity into the batteries. I use an advanced power

factor charger that is about 95% efficient. So I have to use about 17.461 kWh of electricity from

the wall to replace that 16.588 kWh of electricity.

Yes, the entire range of my car is based on its ability to store the usable energy in one half of a

gallon of gasoline. The good news is that it uses an average of 225 wH of electricity per mile from

the batteries.

Terms:

Battery Technology: LiFePO4

Lbs/Cell: 7.42

Cells/Battery pack: 64

Battery pack AH: 5760 AH

Voltage: 3.6

AH/Cell: 90Nominal storage capacity: [(AH/Cell)*(Cells/Battery pack)] * Voltage

Nominal storage capacity: 20.736 kWh

Usable storage capacity: 16.5888 kWh

Cost of recharge in kWh: 873 kWh

Charger efficiency factor: 95%

EV Power/Distance: 225 Wh per mile or 140 Wh per km


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ICE engine versus Electric motor

Unit Internal combustion Electric motor vehicle

wH/mile 1200 236

Percentage of ICE Wh 100% 19.66%

Parameter Cost Currency

Dollar 13.50 MXP

Regular gallon May 2012 4.09 USD

Liter in U.S. May 2012 1.0804 USD

Liter in U.S. May 2012 14.5863 MXP

Liter in Mexico May 2012 10.84 MXP

Liter in Mexico May 2012 .8338 USD

Gallon in Mexico May 2012 3.1562 USD

Gallon in Mexico May 2012 42.6087 MXP

Ejemplo de J. Rickard con costos actuales en Mxico

Variable Valor Unidad

Costo del kwh en Mexico 2.619 Pesos para excedente de 1C

Watts usados en las bateras 17461 Wh

Costo de la carga (tanque elctrico) 45.73 Pesos

Energa consumida por milla 225 Wh

Capacidad usable 16.58 kWh

Autonoma 73.72 Millas

Autonoma (km) 117.95 KmCosto por milla .6203 Pesos

Costo por kilmetro .3877 Pesos por kilmetro

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