Thread: Batteries
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Old 11-10-19, 07:39 PM
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fly135
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Bikes: iZip E3 Peak DS, Magnum Metro, GT Tachyon, K2 Sidewinder

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Originally Posted by PreacherG View Post
I understand different voltage and how multiple cells produce the desired voltage. My question is on battery capacity. Does a 10 Ah battery deliver 10 amps at the specified voltage, i.e. 48 V, 10 Ah will deliver 480 watts, then is dead? V x A = W
Or does the mean it can deliver power at a RATE of 10Ah, or 166 ma / min? For how long?

In other words, will a 48V 10Ah battery power a 250W motor running battery only full power for about 2 hours or a 500W motor running full power for about 1 hour? Clearly, the 500W would be much faster.? A 36V 10Ah battery would power the 250W motor for 1 hours?

Can I determine the amount of power stored in a battery by multiplying V x Ah = Watts? Is this not a better determination of range, because the bike will draw the same wattage for the same riding conditions, up to the max motor rating?
10Ah means it can deliver 10 amps for an hour or 600amps for a minute. However, it really won't deliver 600 amps for a minute, and it may not even deliver 10 amps for an hours. Amp-hours are normalized to an hour, but the actual capacity might only be realized at a lower current draw. For example a 10Ah battery might deliver 5amps continuous for 2 hours, which still equals 10Ah. So the battery capacity might be realized running the 250w full bore, but maybe not the 500watt. The answer would be to look and see at what continuous load a battery's capacity is measured. They might actually deliver 10 amps for an hour.

V x Ah = watt-hours, and yes that's the actual energy capacity vs. Ah which doesn't give you the energy without the voltage specified. Not sure how bad it is to run them empty. I believe the controller will shut down and protect the battery on low voltage.
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