BEIJING (Reuters) -China's BYD posted a 21% rise in second-quarter electric vehicle sales, closing the gap with Tesla after handing back the world's top EV vendor title to the U.S. rival in the first quarter. Tesla's second-quarter deliveries fell by a smaller than expected 4.8% to 443,956 vehicles on Tuesday, but that still marked the first time the U.S. firm posted two straight quarters of decline as it deals with stiff competition in China and slow demand due to a lack of affordable new models. Price cuts and incentives helped Tesla beat expectations, however, pushing shares up about 5% in morning trading.