Apple has issued software updates for 2012 13-inch and 15-inch MacBook Pro with Retina displays, and 2012/2013 MacBook Airs to resolve issues having to do with batteries. The updates are available via the Software Update function in the Mac App Store.
This update is recommended for MacBook Air (mid 2012 and mid 2013) models. This update addresses rare issues where the battery unexpectedly stops functioning, the system does not recognize the battery, or the system hangs when the battery charge reaches less than one percent.
MacBook Pro SMC 1.2 release notes shown in screenshot above.