Apple revealed three SMC updates for their MacBook Air, MacBook Pro and MacBook Pro Retina series. The released patches aim to fix minor issues about battery drain. Users have expressed concerns and problems about the MacBook series and when battery gets drained to zero.

The release notes indicated that affected models included the mid-2012 MacBook Pro and Retina MacBook Pro. As for the MacBook Air, the update covers models from mid-2012 to mid-2013.

The first update is the MacBook Pro's SMC Firmware Update 1.8. The release notes explain:

This update is recommended for MacBook Pro (mid 2012) models.

This update addresses rare issues where the battery unexpectedly stops functioning or the system hangs when the battery charge reaches less than one percent.

As the note implies, the update seeks to resolve a "rare" problem wherein a battery reached more than 1000 charge cycles and suddenly stops functioning or shuts down.

A similar update has been released for the MacBook Pro Retina. The note for the SMC Update 1.2 says:

This update is recommended for 13-inch MacBook Pro with Retina display (late 2012) models, and 15-inch MacBook Pro with Retina display (mid 2012) models.

This update addresses rare issues where the battery unexpectedly stops functioning or the system hangs when the battery charge reaches less than one percent.

The update may be around 504 kb but it can resolve a number of issues especially regarding slow frame rates. The update can improve frame sequences when playing games specifically on the 15-inch model. It also addresses Power Nap bugs.

Lastly, the MacBook Air SMC Update 1.9. The note says:

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.

There are no indications about the real extent of the battery bug. However, going through a number of Apple Support communities should reveal the number of people who have expressed their concerns about it. Users can visit Apple's Support Downloads webpage for more details. They can also refer to the device's Software Update section.

The updates are also just in time to for the reported release of the 2013 MacBook Pro.