Energy Capacity of the Hybrid Battery

[max2prius]

I have always wondered, does anyone know what the hybrid battery capacity is in Kilowatt hours? I have tried to do a search but it only states in amp hours which I have no idea to convert to KWH.

I have owned my first Prius since Dec 1, 2007 and am loving it.

Thanks

[haiku88]

Originally Posted by max2prius

I have always wondered, does anyone know what the hybrid battery capacity is in Kilowatt hours? I have tried to do a search but it only states in amp hours which I have no idea to convert to KWH.

I have owned my first Prius since Dec 1, 2007 and am loving it.

Thanks

(amphours x volts)/1000 = kwh

[diamondlarry]

It seems to me that I've heard it is 1.2 or 1.3 KWH.

[jdenenberg]

Originally Posted by max2prius

I have always wondered, does anyone know what the hybrid battery capacity is in Kilowatt hours? I have tried to do a search but it only states in amp hours which I have no idea to convert to KWH.

As stated above the capacity is 6.5watt-hours*200volts = 1.3 kwatt-hours. Only about 1/2 of that is actually available for use to protect the battery from early failure. The capacity will slowly degrade over the life of the car so mine may be down to as low as 50% of its original capacity at this time (4 years and 107,000 miles.

My Prius still gets the same great MPG now as it did when new so the battery is still doing the job.

JeffD

[miscrms]

A small correction, 6.5Ah * ~200V = ~1.3kWh. In general for DC systems, Volts * Amps = Watts, and similarly Volts * Amp hours = Watt hours. AC can be trickier.

You can find more info on the Prius battery here:

Toyota Prius Battery Specs - EAA-PHEV

Rob

[hobbit]

You only get 600Wh of that to play with, though, due to the SOC
limits. Which allows you to suck up about 600 vertical feet
of drop, coincidentally. Here [in the second part] are some
experiments and commentary that you might find amusing.
.
_H*

[Qlara]

From Toyota's Prius spec:
Traction Battery

Battery Type
Sealed Nickel-Metal Hydride (Ni-MH)

Battery Power Output
28 hp (21 kW)

Battery Voltage
201.6V

Capacity
6.5Ah or 1.31kWh

[priusenvy]

OP asked for energy capacity, not power output.

Power = energy/time, or energy = power * time

The power rating of battery tells you how fast it can deliver the energy contained in it, but tells you nothing about the total energy stored in the battery. Energy density and power density of a battery are two different properties of a given battery technology, but both are important in automobile powertrain applications. In greatly simplified terms, they dictate how far you can go and how fast you can go. Two different things.

That ends today's 8th grade physics lesson.

[ronhowell]

Originally Posted by Qlara

From Toyota's Prius spec:
Traction Battery

Battery Type
Sealed Nickel-Metal Hydride (Ni-MH)

Battery Power Output
28 hp (21 kW)

Battery Voltage
201.6V

Capacity
6.5Ah or 1.31kWh

So, if you extracted all of the effective HV battery capacity of 1.31kWh at the maximum power output of 21kW, it would maintain that power level for 1.31/21 x 60 = 3.74 minutes. That assumes the quoted 1.31kWh capacity is the effective allowed capacity between the upper and lower charge limits.

Not a lot of time, eh! Which is why you need that ICE sucking, squeezing, banging and blowing that hi-energy fossil fuel in parallel. There's a lot more energy in that stuff, which is just as well; most of it gets lost before it gets to the road-wheels.

[Philosophe]

Originally Posted by jdenenberg

As stated above the capacity is 6.5watt-hours*200volts = 1.3 kwatt-hours. Only about 1/2 of that is actually available for use to protect the battery from early failure. The capacity will slowly degrade over the life of the car so mine may be down to as low as 50% of its original capacity at this time (4 years and 107,000 miles.

My Prius still gets the same great MPG now as it did when new so the battery is still doing the job.

JeffD

The battery is kept between 40 and 80% of its capacity. Because of this, my understanding was that the capacity is barely affected over time... If your battery only had 50% of its original capacity, wouldn't it show in your mileage? (especially in city driving where regenerative braking is so important)