A Boeing 787 Dreamliner took to the air on Monday to test its newly redesigned battery, the first 787 flight since battery troubles sidelined the fleet in January.

The lithium-ion battery that debuted in the Dreamliner in late 2011 was designed to run cleaner than its predecessors, using stored electricity in addition to fossil fuels. According to Boeing, the Dreamliner runs on 20 percent less fuel than other airplanes in its class.