BYD disclosed Tuesday that its of battery-powered passenger cars totaled 16,301 units last month. : BEIJING — Chinese automaker BYD sold more than twice as many battery-powered electric cars as start-up Nio delivered in March. BYD, which is backed by U.S. billionaire Warren Buffett, disclosed Tuesday that sales of its battery-powered passenger cars totaled 16,301 units last month. That's more than double Nio's deliveries in March of 7,257 cars. Rival start-up Xpeng delivered even fewer vehicles, at 5,102 units last month. Both companies still beat analysts' expectations with those figures.