On Sat, Feb 14, 2009 at 01:56:22PM -0500, Mikus Grinbergs wrote: > I have found the XO-1 batteries (mfg by BYD Company Ltd) to be very > stingy with energy loss. When I put one back in after a month out > of the case, the XO software told me it was still 94% charged.
The displayed state of charge is stored in the chip in the battery, and is maintained by the EC. The battery does not change it's own state of charge value. I don't think that batteries outside the XO will have their state of charge value changed by the chemical self-discharge process. But once the terminal voltage becomes significantly inconsistent with the state of charge value, I imagine that the terminal voltage is trusted more. (If one discharges an XO battery outside the XO using a home lighting circuit, the displayed state of charge will be inconsistent. Persisting in this practice results in increasing inconsistency. Ceasing the practice results in decreasing inconsistency over several XO moderated charge and discharge cycles. The inconsistency results in forced power-down before the state of charge would suggest, manifesting as "my XO stops too soon".) > James Cameron mentioned measuring a current draw of 24mA. I suspect > this was *not* on a thoroughly "shut-down" G1G1. Wrong. It was on a thoroughly shutdown mass production unit. The unit was shutdown using the Sugar shutdown option, then the DC cable and the battery were removed, 30 seconds were allowed to elapse, and then the DC cable was reinserted. The measurement was after this reinsertion. > In my experience, > after two days in a "shut-down" state the XO software shows the > battery charge % to be somewhere in the mid-90's. You observe a difference between my measurements and yours. I knew the technique was inadequate, but I was providing it as a maximum. I had already said that I thought the external DC supply path to contain additional losses. Richard has explained that the difference was due to the EC not stopped, because it knows it is on external DC supply. -- James Cameron mailto:qu...@us.netrek.org http://quozl.netrek.org/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel