A little over a month ago, there were reports from many users that had noticed a significant decrease in battery life on their laptops after upgrading from Lion to Mountain Lion. While the first update, OS X 10.8.1 did improve battery life, new testing shows that the current developer’s seed of OS X 10.8.2 completely restores battery life back to pre-Lion levels.
The Mac Observer has performed a new set of tests, its most extensive so far, testing the effect on battery life when updating from OS X 10.8.1 to Build 12C35 of OS X 10.8.2, and also looking at upgrades from OS X Snow Leopard to OS X Lion.
The study shows that the testing build of 10.8.2 completely restores battery life to pre-Mountain Lion levels, giving approximately 380 minutes of power, compared to 260-275 under OS X 10.8.0 and 280-300 minutes running under OS X 10.8.1.
Not all users have experienced the battery life decrease under Mountain Lion, so it’s not clear what the exact cause of the issue is. But, for those suffering with the problem of decreased battery life, OS X 10.8.2 may be a welcome resolution to restore full battery life to their notebooks.