How to Fix Bad iPhone Battery Life on iOS 5.1.1 in 5 Minutes Josh Smith05/21/2012 Is your iPhone battery life lower after the iOS 5.1.1 update? We’re hearing from readers that the iOS 5.1.1 update results in bad battery life on the iPhone 4S and iPhone 4.Advertisement The battery life of my iPhone 4S remains steady, so this iOS 5.1.1 battery life issue is hit or miss. Read: How to Get Better iPhone Battery Life If your iPhone battery life is bad on iOS 5.1.1 here’s how to fix it in a few minutes.Advertisement Advertisement How to Fix Bad iPhone Battery Life on iOS 5.1.1 Indication of bad battery life. Before you try to fix bad iPhone battery life I suggest making a backup of your iPhone. To do this plug in to your computer and sync. If you don’t already do so, this is a good time to set up WiFi sync. To fix bad iPhone battery life on iOS 5.1.1 we are going to reset the iPhone settings. This is a fresh start for every setting on the iPhone, but it does not delete the apps and data on the iPhone. 1. Open the Settings App.Advertisement 2. Tap on General. 3. Scroll to the very bottom and tap on Reset. 4. Tap on Reset All Settings.Advertisement 5. If prompted, enter your Passcode. 6. Wait for the reset to finish.Advertisement 7. Use the iPhone until the battery at 0% and the phone turns off. 8. Plug in the iPhone and charge to 100%. 9. This should fix most iOS 5.1.1 battery life issues. 10. If you continue to experience bad battery life you may need to perform a complete iPhone reset. The iPhone will ask you to enter WiFi and other setting information as if it was taken out of the box. I suggest reading 10 iPhone 4S settings to change, in order to make sure your iPhone is set up right.