Mackanic and Yu, Stanford University (IMAGE) Stanford University Caption Lead authors and Ph.D. students David Mackanic, left, and Zhiao Yu with their battery tester at right. Yu holds a dish of already tested cells that they call "the battery graveyard." Credit Mark Golden Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.