FS#8505 - Wrong battery levels on sansa e200

Attached to Project: Rockbox
Opened by Kim Hauritz (haudyr) - Wednesday, 23 January 2008, 20:08 GMT
Last edited by Dominik Riebeling (bluebrother) - Saturday, 08 March 2008, 13:58 GMT
Task Type Bugs
Category Battery/Charging
Status Closed
Assigned To No-one
Operating System Sansa e200
Severity Low
Priority Normal
Reported Version Daily build (which?)
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 0
Private No


I have a Sansa e280 and the new battery levels for Sansa e200 added in
revision 16122, predicts a battery life of about 4 hours and fully
charged reads about 80%, after 3 hours of playback it reads about 25%.

The levels from the previous revision is more accurate and predicts
the battery life to about 12 hours and fully charged reads about 100%, after 10 hours of playback it reads about 15%.

I recommend a roll back to the old levels.
This task depends upon

Closed by  Dominik Riebeling (bluebrother)
Saturday, 08 March 2008, 13:58 GMT
Reason for closing:  Fixed
Comment by Christina Louise (AthenaOfDelphi) - Sunday, 03 February 2008, 20:14 GMT
I have also noticed this issue, with roughly the same times and levels as Kim.
Comment by Andree Buschmann (Buschel) - Tuesday, 05 February 2008, 15:35 GMT
I cannot explain this difference from the changes in source code. With this patch it is "easier" to reach 100% (now 4.16V = 100%, before 4.2V = 100%) and the main changes are in lower voltage area and avoid the "%" stying at 40% and drop to 0% within 30 minutes. The estimated battery life was not directly touched with this change -- estimated runtime for 80% capacity must be still the same, with or without this change.
Comment by Kim Hauritz (haudyr) - Tuesday, 05 February 2008, 19:49 GMT

I can see your point Andree.
I will try to use the current revision, for now, and check it for a couple of charge cycles.

Comment by Kim Hauritz (haudyr) - Friday, 08 February 2008, 20:45 GMT
I have now tested the current revision and it works fine, the battery levels is more accurate now.

The problem was not with the new levels as i first thought but more likeley a bug was triggered
in the build from the 23/1-08 on my sansa so it gave false readings of the battery levels,
and probably also on Christina's sansa, but for all i know it has been fixed in the build from the 5/2-08.

So if you observe similar problems on your sansa, try upgrading to the current build, it may fix the problem.

Thanks Andree for the new battery levels :-)

I think we can close this case.

Best regards
Kim Hauritz
Comment by Christina Louise (AthenaOfDelphi) - Sunday, 10 February 2008, 14:34 GMT
I downloaded and installed the latest build last night. With my Sansa fully charged, I got the correct battery level. I'm currently just running the battery down and so far, the levels look correct.

Thanks :-)

Just like to say, this is an excellent project, thanks to everyone who makes it possible.
Comment by Andree Buschmann (Buschel) - Tuesday, 12 February 2008, 14:21 GMT
So, anyone please close this one.