Battery Life way seems too short

[bloodbath]

My Sansa e260R is kinda new (2 or 3 months old) and so the battery should be in good condition.  However, after I fully charge my battery, I have (according to Rockbox) less than five hours of battery life.  I've read other topics in the forum that state Rockbox will drain the battery about two times faster than the original firmware.  However, this seems to be over 4 times faster.  Is there something screwy with my battery or is Rockbox not reading the battery status correctly?  Thanks in advance.

[Chronon]

Have you run a proper test?  Don't trust the battery lifetime predicted by Rockbox as this has not been calibrated at this time.  Here's a result that someone else got:
http://www.rockbox.org/twiki/bin/view/Main/SandiskE200BatteryMeasurements

[bloodbath]

Thanks for the info.  It's good to hear that Rockbox isn't accurate at the moment (at least this is good for me considering the amount of time it's stating I have left).  Do you have any idea when the battery status will be calibrated?

Thanks again.

[Chronon]

My understanding is that a proper calibration requires detailed knowledge of the discharge curve of the battery.  I think that the proper data has simply not been gathered across all targets.

[saratoga]

The Sansa was using the Archos current settings for some reason.

http://svn.rockbox.org/viewvc.cgi/trunk/firmware/export/powermgmt.h?r1=15388&r2=15389

Which is odd, since Toni posted this info last April.  We should really give him SVN access so these things get committed sooner.

[Lear]

I'm testing with a new discharge curve, based on my own measurements (one battery_bench run only, so far), and the measurement on the wiki that is close to it (the other has noticeably higher voltages for some reason), as well as better current estimates (at least for the "normal" state; backlight and record are still wild guesses). Looks promising, but I'd like to use it a bit more first.

Or maybe I should just commit it, since it is likely to improve things...