Electric-car safety tests faulted
Experts have questioned whether the mainland's safety tests for electric cars were rigorous enough after an electric taxi burst into flames, killing three, when it was struck from the rear by a speeding sports car.
The e6 electric taxi made by the Shenzhen-based company BYD was destroyed by fire following the collision early on Saturday, killing its driver and two passengers.
Experts said tests used to measure the all-electric car's ability to survive collisions were not conducted at a speed high enough to simulate the most severe real-life crashes.
Wang Zidong , who is in charge of car-battery testing at the China North Vehicle Research Institute, told the Economic Information Daily that collision tests for mainland-made electric car batteries were only conducted at speeds between 40km/h and 70km/h and that manufacturers had not considered crashes at speeds in excess of 100km/h. A witness was quoted as saying the car that rammed the taxi was doing between 150km/h and 200 km/h.
'If you look at the spontaneous-combustion accidents of [mainland-made] electric cars, surely there are many technical defects and areas that need to be improved,' said Wang, who has done collision tests at 50 km/h for BYD's electric cars.
Wang said collision tests in excess of 100km/h could take one to two years to complete and required the destruction of many more cars than at present. 'Mainland companies aren't willing to do it,' he said.
BYD said its electric cars had been fully tested in accordance with national standards and complied with all regulations. It said that in more than two years there had been 18 rear-end collisions involving its electric taxis, with no injuries or fatalities reported, nor had any car caught fire.
'The batteries for the BYD e6 have withstood crush tests by authoritative agencies of the government,' the firm said. 'During the test, they did not catch fire even when 50 per cent of battery modules were deformed.'
BYD shares fell 2.58 per cent in Shenzhen and 5.9 per cent in Hong Kong on Monday.
Professor Sun Zechang , of Tongji University's School of Automotive Studies, said the mainland's collision tests were conducted using too small a sample to reflect the hundreds of battery modules installed in electric cars.
Sun told Caixin Magazine that just because some of the modules passed the collision tests, it did not mean it was safe to put all of them on the road.
The magazine quoted a battery industry insider as saying that many collision tests for electric cars' batteries were conducted when the batteries were only half charged, so fewer problems would be exposed during laboratory tests.
There are 300 electric taxis and 200 electric buses in use in Shenzhen, and the city plans to increase the number to 3,000 taxis and 1,000 buses by the end of 2015.