Why do some batteries use kWh to define the capacity and other batteries use mAh?

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Why do some batteries use kWh to define the capacity and other batteries use mAh?

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Anonymous 0 Comments

Single cell batteries are typically rated with mAh since their voltages are always the same. IE: Lithium batteries are almost always 3.7v. A, D and C batteries are always 1.5v (Or 1.2v for rechargeable ones). So watts don’t really matter as the voltage will stay the same.

Where as multi-cell batteries like those in hybrids and EV’s consist of several batteries wired together, which changes the voltage. These are usually rated with kWh since their voltages will often be different. Most EV’s use around 350VDC, and most non-plugin hybrids are around 250VDC.

Anonymous 0 Comments

Well you can convert pretty easily between watts and amps if you know the voltage. It’s probably just tradition in how they rate themselves. For instance you wouldn’t expect car batteries and flashlight batteries to use the same scheme, would you?