mAh vs Wh

Why do people measure energy in mAh instead of Joules?

mAh gives a bigger number which sells more batteries, most people don't know wtf mAh, Wh or even Joules are, they only want big numbers.

Same reason people use cm/in to measure the lengths of your dick instead of kilometers and miles.

You don't see people saying "my penis is 6.313×10^-5 miles long" or "my penis is 1.016×10^-4 km long"

>>55770804
Except centimeters and kilometers are both measures of distance. Amps and Watts are different types of measurement.

>>55770804
The problem is, that E = U * Q, while E being measured in Wh (1 Wh = 3.6 kJ), U in Volts and Q in Ah (1 Ah = 3.6 kC). Therefore the energy is bound to the voltage, which can vary from battery to battery and is never told.

>>55769551
It's all relative. Both Wh and mAh change based on discharge rate, and voltage + mAh can give you a better idea of how many cells are in the thing, which is useful to some.

It barely matters, your average user wouldn't know how to (or care enough to) calculate how much theoretical battery life they get from a given battery, and anyone who could do those calculations won't have trouble converting a few units anyway.

>>55769551
A = C/s
1 mAh = mC/s * 3600 s = 3.6 C

You literally could have googled it.

>>55773861
What the OP is saying is that you'd still need to factor in potential to get the actual energy.

>>55773927
It makes no difference since you don't need to know the actual energy to know how much capacity is left in the battery. The capacity is dependent on charge, not voltage. Knowing the voltage only lets you know what the energy is, which doesn't matter.

for things like battery banks, it will be regulated 5v output, so you just use that as a standard value.

>>55770714
Then why not use mili-watt hour?

>>55775692
>>55769580
>>55769551
Q is charge in battery [Ah]
W is energy in battery [Wh]

Ah in base unit is Ampere*3600*seconds i.e. A*3600*s

While Wh in base unit is Watt*3600*seconds = ... = (kg*m^2)*s^-2*3600

See the difference?

>>55774141
is that necessarily the case or...?

sorry for the stupid question

>>55774141
Battery banks are even worse. Say you have one with 10.000 mAh. The battery nominally has 3.7V. That would make ~5.400 mAh at 5V.
Now to make things even worse, the voltage is not stable. Depending on how far they overcharge the battery (increases capacity, reduces useful cycles), it may start at as high at 4.2V and drop to some 3.2V or so when the charge is depleted.

And so, Wh would be a much more accurate measure for the consumer, because it includes the drop of voltage in the calculation, but it also makes things MUCH more complicated to measure.