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Nicklaus

macrumors 6502
Original poster
Jun 19, 2010
263
3
Winter Park
Using iStats my mac battery shows a design capacity of 8460 mAh I have rechargeable AA batteries that say they are 2500 mAh. So is it equivalent to a little more that three AA batteries? It can't be possible these are the same thing right? Are laptops that efficient now? :confused:
 
Using iStats my mac battery shows a design capacity of 8460 mAh I have rechargeable AA batteries that say they are 2500 mAh. So is it equivalent to a little more that three AA batteries? It can't be possible these are the same thing right? Are laptops that efficient now? :confused:

Laptop batteries are higher voltage, and so at the same mAh rating, store more power. Best to compare watt-hour ratings. Your AAs stay around 1.3-1.4 volts, and the MBPR is rated at 11.2 volts (95Wh divided by 8.46Ah). The AAs would be somewhere around 3Wh.
 
mAh is is the amount of time the battery will work given a constant current draw at it's given voltate (typically 1.2v for a rechargable AA).

power consumption is actually measured in watts, which is amps (or in this case milliamps) multiplied by the voltage necessary to run the devices.

In order to power the rMBP with your AA's you'd need 10 batteries in series to get to the required 12v, but they would only have a charge time of 2500mAh, so you'd need three and a half groups(in parallel) of ten(in series) to get about the same capacity of the built in battery.
 
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