Electric vehicles (EVs) will meet the daily travel needs of drivers longer than commonly assumed, according to the first study of its kind carried out by scientists at the US Department of Energy's Lawrence Berkeley National Laboratory. Many drivers and much prior literature on the retirement of EV batteries have assumed that EV batteries will be retired after the battery has lost 20 percent of its energy storage or power delivery capability. This study shows that the daily travel needs of drivers continue to be met well beyond these levels of battery degradation.