battery level from command line

[Mikkel L. Ellertson]

max wrote:
> Mikkel L. Ellertson wrote:
>> Mike -- EMAIL IGNORED wrote:
>>>
>>> Interesting.  But it still begs the question of how it
>>> decided that the "last full capacity" was in fact a
>>> full capacity.
>>>
>> There is a chip in the battery that decides this. It is part of the 
>> charging circuitry. Because it controls charging, when it decides the 
>> battery is full, it will not charge any more.
>>
>> Mikkel
>>
> Can it be reset?
> 
> Max
> 
Not really, without opening up the battery, and making a connection 
to the communications bus in the battery. At least I don't know of 
any way to send commands to the chip while it is in the laptop. You 
can recalibrate the chip by first charging the battery until the 
laptop says it is full, discharging it down to about 5%, and 
recharging it. (Check your laptop manual for the recommended 
discharge level for your laptop.) If you laptop has it, running the 
battery test will discharge it to the correct level. I have seen 
this in a couple of BIOS, and as a stand alone diagnostic disk or 
boot partition.

But this is probably not going to reset the full charge level. There 
is a lot of information on this on the web. If you search for 
rebuilding laptop batteries, you will probably find it. This is a 
common problem when replacing bad cells - you don't get a full cycle 
without resetting the chip. There is a Linux program that lets you 
"talk" to the chip using a serial port and a special cable.

Mikkel
-- 

   Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

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