September 9th, 2009

Zaurus battery charging

Besides my spitz C-3000 segfaulting about 3 times per kernel compile (do all of them do that, or is just mine affected?), I have some problems with charging. It seems to charge very very slowly why turned on. I learned to shutdown back to Sharp bootloader for charge, but I still forget sometimes.

I have been looking at battery code, and it seems it still leaves something to be desired. First, it goes from 100% to 60% way too quickly (and yes, it may be my cell just going old. OTOH, at this point, most of the cells are old :-). While compiling kernel, brigness 31, I unplugged AC power at 10:00. Before unplug, indicated battery was 219, 100%. Immediately after that, it went to 204, 78% and continued to decline rather quickly:

10:01				  202,  73%
10:04				  199	65%
10:06				  197	60%
10:10				  194	53%
10:13				  193	50%
10:14				  192	48%
10:19				  190	43%


Other problem seems to be in the charging code; it only checks battery temperature once, and only seems to stop charging if temperature is too high. But li-ions should not be charged in too low temperatures, either. (I have summer here just now, but could someone mamybe get temperature values from spitz at cca 5 degrees Celsius?)