Better Battery Performance (No this ain't a useless ZTE post ;) )

[Guest PsYcHoKiLLa]

Found this and thought it might be helpful to peeps...

There are many custom ROMs available for Android and sometimes we can’t help but to try every ROM to see what’s best for our device in terms of battery life, performance, etc. There are times that you will notice a significant battery drain after flashing a new ROM — After 8 hours on Airplane mode it goes 5% down or after 8 hours of “deep sleep” it goes 20-30% down – it could be a work of a third-party app or a system misbehavior. Before flashing a new ROM, make sure that your device is fully charged. Wait until your battery have had 2-3 battery cycles – Battery should not be below 10% — before concluding that the ROM drains your battery. It’s also important to calibrate your battery every time you flash a ROM on your Android device

• Before restoring all of your apps from Titanium Backup, select only the ones that you need most. Don’t restore games and other apps yet. See if your battery would last for some time. If you see no problem with the battery, restore your other apps from TB. If you notice a battery drain, then it could be a work of a third-party app.
  
• Download CPU Spy on Google Play Store to see if your device is going into a Deep Sleep. If it’s not going into a deep sleep, then Download and run BetterBatteryStats and go to Partial Wakelocks to see which is preventing the device from going into deep sleep.
  
• Check Settings>Battery, and if you see Media Scanner at the top of the list then it could that there are some corrupt thumbnails or database that makes the Media Scanner run berserk. To Fix, use SGS Tools, choose [Apply script] then select [clean_thumb_db.txt] and execute the script, reboot.
  
• Download Battery Calibration on Google Play Store and perform a battery calibration whenever you flash a new ROM.
  
• Another way to calibrate your battery is to reset fuel gauge. By using a file manager like Root Explorer, mount to r/w, /sys/devices/platform/i2c-gpio.9/i2c-9/9-0036/power_supply/fuelgauge/fg_reset_soc and insert 1, then Save and exit. Your battery stats will display a crazy result but it will adjust after 1-2 charging cycles. (Not sure about this last one it's most likely device specific and so won't apply to ours)
  

[Source]

Edited May 26, 2012 by PsYcHoKiLLa

[Guest daemius]

very useful, will try it later, thanks

[Guest gabriwinter]

Hi I followed your instructions and I cant figure out why my phone doesnt go in to deep sleep.

Im using latest cm9 build

Edited May 29, 2012 by gabriwinter

[Guest Dazzozo]

Another way to calibrate your battery is to reset fuel gauge. By using a file manager like Root Explorer, mount to r/w, /sys/devices/platform/i2c-gpio.9/i2c-9/9-0036/power_supply/fuelgauge/fg_reset_soc and insert 1, then Save and exit. Your battery stats will display a crazy result but it will adjust after 1-2 charging cycles. (Not sure about this last one it's most likely device specific and so won't apply to ours)

This won't work for us (as is) but something in /sys/devices/platform/ may have a similar effect. Feel free to have a poke around. ;)

[Guest dodgetimmy]

Hi I followed your instructions and I cant figure out why my phone doesnt go in to deep sleep.

Im using latest cm9 build

I have the same problem as you, the phone won't enter deep sleep, even with no obvious wakelocks in better battery stats.

[Guest PsYcHoKiLLa]

Try looking at the following in your sound settings :

Settings > Sound

Uncheck "Touch sounds"

Uncheck "Screen lock sound"

If the top process shown causing partial wakelock is AudioOut_1

Edited July 22, 2012 by PsYcHoKiLLa

[Guest dodgetimmy]

The top process for me wasn't audioOut_1 like above.

I worked out what the problem was anyway. I hope it helps someone with the same problem.

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Settings>Wireless and Network Settings>Wi-FI Settings>(Menu) Advanced>Wi-Fi Sleep policy must be set on "when screen turns off"

When this is not set, it prevents the phone from deep sleeping.

Should it be the case that this happens? Or should the Wi-Fi sleep too? I know sleep is is in the Wi-Fi specification.

Sadly because some applications I use have a delay when using wireless data, this causes a problem for me.

Edited July 22, 2012 by dodgetimmy

[Guest PsYcHoKiLLa]

WiFi should really sleep too but as stated in the thread itself CM9 (and now CM10) is a work in progress.

[Guest dodgetimmy]

Work in process for the Gingerbread roms too? I am using FNC7

[Guest PsYcHoKiLLa]

Hmm well the FnC series (I think) uses one of the stock roms as a base so shouldn't really have the same problems I would think.

[Guest dodgetimmy]

Strange how I get this problem with fnc then. Even with it enabled though, so far i have 30 mins at 245mhz and only 5 in deep sleep