Toyota Motor Corp., whose Prius dominates the market for hybrid vehicles, said its next generation of batteries will be more efficient and improve mileage.

Toyota¡¯s future hybrids will have batteries with higher energy density and power, Satoshi Ogiso, chief engineer for the Prius line, hybrid vehicles and plug-in hybrids, told reporters Wednesday. He didn¡¯t give details about when the carmaker¡¯s next hybrids will arrive or specifics about mileage.

¡°The current Prius has been America¡¯s fuel economy king for many years,¡± Ogiso told reporters at a briefing in Ypsilanti, Michigan.