Originally Posted by Polarfuchs
I unplugged and replugged the charger instead of only checking the cables of the Asus docking station.
And I ran advanced task killer, killed a bunch of apps.
After this it began to charge really quick, as I was used to it.
Now the battery is as 100%
shows 4.179.000 µV
Which is the same as the app "akku&batterie hd" by smallte.ch reports.
So if I can exclude a hardware error, some software must have caused it.
But my highest usage shows "display" that caused 73% of the drain.
Well, if you are charging the device with the screen on, it is certainly going to charge more slowly. I can drain my device in four or five hours merely doing light browsing - most of that is just the screen.
If there is something that is causing one or more of the CPU cores to be running at full bore, the battery will certainly charge even more slowly - see the prior maths that demonstrate that a 2A charger can not charge the battery at it's maximum rate (~1.7A) if a whole bunch of stuff is happening on the tablet. But just the screen alone can do that if it is on.
But you never bothered to mention what state the device was in (screen on etc).
If the device is capable of sleeping (there are no wake locks held by running apps), it will enter the LP0 state and the power drawn by the motherboard will be nearly zero. You will see LP0 mentioned in the kernel log (/proc/kmsg) if it is deep-sleeping.
I never said "software can't cause the battery charge rate to diminish". What I said was that if no software is running at all - the device is powered off - then if you do not observe a charging rate in excess of 30%/hr, the problem is hardware. The LP0 power state (tab in deep sleep, no wake locks held) also approximates a power-off condition.