Increase iPhone Battery Life on iOS 5.0 or 5.0.1 by editing system power profile plist file

Are you a heavy iPhone user and always struggling with saving power on your device? Here’s something that you can try on your jailbroken iOS 5.0 or iOS 5.0.1.

Just like a computer’s operating system, iOS also comes with a power management system that adjusts how much your device uses power. By editing the com.apple.SystemPowerProfileDefaults.plist file, you may be able to squeeze more juice out of your battery.
I left my iPhone overnight at 85% battery power with WiFi, 3G and GPS turned on. By 8am the next day, it only consumed 2% of power. Not too bad at all.
Steps:
1. Download DiskAid or i-FunBox.
2. Download one of these power profiles:

• Ultra power saving profile ultra_power_saving_mode.zip
• Medium power saving profile medium_power_saving_mode.zip
• Default power profile default_power_profile.zip

3. Launch DiskAid or i-FunBox and browse to the following folder location:

/System/Library/CoreServices/powerd.bundle/

4. Replace or overwrite the com.apple.SystemPowerProfileDefaults.plist with the one you just downloaded in step 2.
5. Reboot your device and you’re done!
If you like to revert to default power profile, simply use the default power profile plist file.
I haven’t tried this on iOS 4.x yet but if you would like to try (at your own risk), the .pfile file is located at the following folder:

/System/Library/SystemConfiguration/PowerManagement.bundle

Did this work for you? Otherwise, iOS 5.0.2 that’s rumored to come out next week may be able to resolve battery issues on all iDevices!