At Google I/O last week, Google announced Project Volta, its effort to change and drastically improve how Android manages battery life. Since then the folks over at Ars Technica have downloaded the publicly available L developer preview build and put it through its paces. Is there a noticeable difference? Yes, apparently. They were able to get an an extra two hours of battery life out of their Nexus 5, an improvement of thirty-six percent. Regardless of how exact these numbers are, the difference suggests good things.
For the process, Ars used a single device, flashed to 4.4.4, signed in, updated apps, charged up, and ran the test (which keeps the screen on and automatically loads a webpage over Wi-Fi every 15 seconds until the battery dies). Then they flashed the same device to the L preview. After performing the test twice each, they took the average and shared their results.
The improvements stem from a number of areas, including a new "JobScheduler" API that allows Android to lump together certain background requests that would otherwise individually wake up the processor. L also uses the ART runtime rather than Dalvik, which is generally easier on the battery. For more details, hit up the source link below.
Source: Ars Technica