Cobbled together from sdx-developers.com and other sites…
I’m as cavalier as anyone on flashing a phone without a full charge. It’s because in the old days I had to worry about a flash failing due to power outage.
It turns out it makes a difference. Flashing a phone erases /data/system/batterystats.bin, and the phone rebuilds the file assuming a completely full battery.
Here’s the solution to longer battery life for free, no magic.
– Charge the battery completely full with the power off. Completely.
– In console (ideally recovery mode) run “rm /data/system/batterystats.bin” to delete system battery data.
– Reboot the phone.
– Run the phone until the battery dies completely.
This should recalibrate the battery, and may even free up some capacity that you didn’t realize was there.