China may exempt electric-car buyers from paying purchase taxes as part of expanded state measures to bolster sales of such vehicles after past incentives failed to spur demand, Vice Premier Ma Kai said. The government may cut or waive the 10 percent auto-purchase tax for new-energy vehicles — China’s term for electric cars, plug-in hybrids and fuel-cell vehicles — and slow down the reduction of government subsidies beyond 2015, according to comments from Vice Premier Ma Kai posted on the Chinaev.org website. Ma also urged local governments to help companies develop electric-car rental services. Shares of BYD Co. (1211) , China’s biggest maker of electric cars, rose in Hong Kong trading amid mounting signs the government is stepping up efforts to fight the thickening pollution that’s choking its people. Last month, Premier Li Keqiang declared war on smog and Hangzhou became the sixth Chinese city to impose restrictions on […]