Re: [PATCH v2] Re: Battery class driver.

From: Bill Davidsen
Date: Thu Nov 02 2006 - 12:53:58 EST


Jean Delvare wrote:
On 10/31/2006, man with no name wrote:
In the case at hand we have mWh and mAh, which measure different
physical quantities. You can't convert between them unless you have
intimate knowledge of the battery's chemistry and condition, which we
don't.

You just need to know the voltage of the battery, what else?

And it would be nice to also allow for power supply devices that use
other, incompatible units like "percent" or "minutes" or "hand crank
revolutions".

Do such batteries exist at the moment, or are you just speculating?

I have seen joules (or mJ) on a laptop. Yes, it was Windows, but I bet the report came from hardware. Some vendor getting anal about metric?
> I
don't quite see how a battery could report remaining energy in time
units, as power consumption varies over time. Hand crank revolutions
wouldn't be a very useful unit either, unless you know how much energy
a revolution provides, and then you can just convert it. Percent would
make some sense, but you can only express the remaining energy this way,
not the total. And if you know the total in mAh or mWh, you can multiply
by the percentage and you get the remaining energy in the same unit.

--
Jean Delvare


--
Bill Davidsen <davidsen@xxxxxxx>
Obscure bug of 2004: BASH BUFFER OVERFLOW - if bash is being run by a
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