Apple has determined that a very small percentage of iPhone 5 devices may suddenly experience shorter battery life or need to be charged more frequently. The affected iPhone 5 devices were sold between September 2012 and January 2013 and fall within a limited serial number range.
If your iPhone 5 is experiencing these symptoms and meets the eligibility requirements noted below, Apple will replace your iPhone 5 battery, free of charge.
Apple says the issue affects only a "limited serial number range" and iPhone 5 users can input their serial numbers on Apple's support site to find out whether their phones need a battery replacement. Those who do have a faulty battery can get a replacement through an Apple Authorized Service Provider, an Apple Retail Store, or through Apple Technical support.
Apple Initiates iPhone 5 Battery Replacement Program