Envia, a startup battery company in Newark, California, has announced a much-anticipated breakthrough in lithium-polymer storage cell energy density. Although tested to 300 charge/discharge cycles, the new battery should show at least 1,000 successful cycles before we get too excited. Excitement will build, though, as the announced 400 Watt-hours per kilogram doubles the current energy density standard for lithium batteries. This would reduce a Leaf’s battery pack from about 600 pounds to 300 pounds, or keeping the same weight, double the car’s range to about 250 miles. Dr. Brien Seeley points out that the Green Flight Challenge-winning Pipistrel G4 could have traversed 400 miles with a reserve on such batteries. According to Envia, quoting from the official report, “’The Naval Surface Warfare Center, Crane Division (NSWC Crane) Test & Evaluation Branch was tasked by Advanced Research Products Agency – Energy (ARPA-E) to perform Verification & Validation testing on two high capacity lithium ion pouch type cells, manufactured by Envia Systems …