back separated and battery appears inflated
This iPhone 4s had been asleep in my wife’s purse for a while . When I removed it to charge it I discovered that the back had separated from the body and the inner back was separated somewhat from the outer. After removing it I discovered the iFixit battery I’d installed some time back seemed to have “inflated” somewhat and was likely responsible for pushing the back away from the chassis. I have two questions: 1) what was the likely cause of all this and 2) can I repair it with a new back and battery? I’ve attached a photo which helpfully shows the problems.