• Wed
  • Jul 23, 2014
  • Updated: 11:58pm

Electric cars: the BURNING QUESTION

PUBLISHED : Wednesday, 04 July, 2012, 12:00am
UPDATED : Wednesday, 04 July, 2012, 12:00am

The drivers of Shenzhen's 300 electric taxis say they are finding passengers harder to come by following a deadly blaze in late May that was triggered by a rear-end collision.

Surveillance cameras showed the e6 electric taxi, made by Shenzhen-based BYD and being driven at 80km/h, bursting into flames just three seconds after a Nissan GTR travelling at 180km/h slammed into its rear. The fire, with flames up to four metres high, burned for 26 minutes before being put out, Xinhua's weekly Oriental Outlook magazine reported last month. Although the driver of the Nissan was only slightly injured, the driver and two passengers in the electric taxi were killed.

It was the fourth fire involving Chinese-made electric vehicles in just over a year. An electric taxi made by Zotye Auto, based in Zhejiang , burst into flames in Hangzhou in April last year, an electric bus made by Shanghai Leibo New Energy Auto Technology caught fire in Shanghai in July and a hybrid bus made by Shenzhen Wuzhoulong Motors burned in Shenzhen in August. Smoke was also seen pouring out of a BYD electric car in Shenzhen that same month.

Chinese experts say increasing concerns over the safety of electric cars should persuade the authorities to suspend a pilot scheme promoting domestically made electric vehicles and take 15,000 off the roads.

Professor Song Jian , from Tsinghua University's vehicle engineering department, said that huge design defects in BYD's electric cars could lead to many safety problems.

'Up to now, lithium iron phosphate batteries [such as those used in BYD's electric cars] haven't been widely recognised by industry experts as being perfectly safe for cars because the batteries can catch fire after a collision,' he said. 'Also, it's unreasonable for BYD to install 600kg battery modules in its electric cars, which account for more than 40 per cent of each vehicle's weight.'

In comparison, the batteries in Chevrolet's Volt electric car weigh around 180kg each, while those in Nissan's Leaf weigh around 200kg.

Song, who is also a deputy director of the state key laboratory of automotive safety and energy, said it was dangerous to put 600kg of combustible substances into a car, and there was no way that BYD's electric cars could actually save energy because the batteries were so heavy that they were actually wasting much more energy than those powered by combustion engines.

He also accused BYD of using a dangerous method to connect the battery modules, which made short circuits more likely when collisions occurred and could lead to fires. 'BYD first uses parallel connections to connect hundreds of single batteries and then uses serial connections to make them into a huge battery module,' he said. 'This could easily cause a short circuit.'

Song said that to respect 'lives and science', the authorities should slow down the promotion of electric cars. He said the 500 or so electric buses and taxis in Shenzhen should be immediately taken off the roads because of safety concerns.

Professor Wei Xuezhe , from Tongji University's school of automotive studies, said he was worried that the electrolyte inside the batteries could leak after a collision, and that an electrolyte with a low ignition point could easily catch fire due to a short circuit or high temperatures following a collision.

'Electrolyte leakage has been blamed for the two electric vehicle fires in Hangzhou and Shanghai last year,' he said.

Saying that battery modules had passed collision tests did not necessarily mean it was safe to put them on the road, Wei said, because the test results largely depended on how they were conducted.

Industry insiders were quoted by Caixin magazine in May as saying that many mainland collision tests for electric car batteries were conducted using too small a sample to reflect the hundreds of battery modules installed in electric cars, and that the batteries were usually only half charged, so fewer problems would be exposed during laboratory tests.

'The authorities shouldn't promote electric cars so rapidly just to pave their career paths and to boost enterprises' business,' Wei said. 'Consumers shouldn't be treated as laboratory mice.'

Wang Zidong , who is in charge of car-battery testing at the China North Vehicle Research Institute in Beijing and part of the team investigating the BYD fire, said that collision tests for Chinese-made electric car batteries were conducted at speeds of only between 40km/h and 70km/h, with BYD's tested at 50km/h.

He told the Economic Information Daily earlier that collision tests conducted at speeds of more than 100km/h could take one to two years to complete and would require the destruction of many more cars than at present. 'Chinese companies aren't willing to do it,' Wang said.

Mainland media has reported that at least two national investigation teams with experts from the State Administration of Work Safety, the Ministry of Science and Technology, the National Development and Reform Commission, the Ministry of Industry and Information Technology and Ministry of Finance have been sent to Shenzhen to investigate the accident. A BYD spokesman said that their report was expected to come out this month.

Wei also argued that electric cars are not necessarily good for the environment given that China and the rest of the world have not solved the problem of how to dispose of thousands of tonnes of used batteries. The batteries in a BYD electric bus weigh two tonnes and the 15,000 electric vehicles on the mainland contain at least 10,000 tonnes of batteries.

Chinese car-industry experts have long argued that electric cars are not as green as their supporters claim, particularly when considering the environmental cost of properly disposing of tonnes of batteries and the fact that coal accounts for about 80 per cent of the fuel mix at mainland power plants.

Wang also confirmed that smoke had been seen emerging from a BYD electric car in Shenzhen during last year's World University Games. That incident has not been reported by mainland media and Wang said it was linked to a control mechanism and not the car's battery.

BYD's Shenzhen headquarters declined to comment on the latest criticism and insisted in an e-mail that its electric cars had been fully tested in accordance with national standards and complied with all government regulations. In May, the company said in a press release that in 18 rear-end collisions involving its electric taxis over more than two years, no previous injuries or fatalities had been reported and no cars had previously caught fire.

There are 300 electric taxis and 200 electric buses on the road in Shenzhen, and the city plans to increase the number to 3,000 electric taxis and 1,000 electric buses by the end of 2015.

In Shenzhen, every electric bus put on the road since 2010 has received a one million yuan (HK$1.22 million) subsidy, half from the central government and half from the city government.

For electric taxis, there are 120,000 yuan in national and local government subsidies.

A car industry analyst who has worked closely with the Shenzhen government said that city authorities had spared no effort to promote electric cars because the car industry made a significant contribution to local gross domestic product and was a major employer.

'New energy technology is also a good talking point for Shenzhen to build up its image and attract investment, although BYD has sold only 1,000 electric cars since the e6 was launched in October last year, compared with the 448,500 combustion- engine cars it sold last year,' he said.

Electric cars, which claim to have zero emissions, are attractive to the authorities as they battle chronic pollution problems, and Beijing has long regarded the new vehicle technology as an opportunity to overtake Western competitors.

Beijing started to promote electric cars in 2009, with a pilot scheme to introduce 25,000 electric taxis and buses in 25 mainland cities by 2012, but mainland media say only five cities have managed to meet their targets so far.

The State Council announced in April that the annual output and sales of electric and hybrid cars was expected to hit 500,000 by 2015, with that number set to jump to five million by 2020. Deputy Finance Minister Zhang Shaochun said in May that his ministry would allocate one billion to two billion yuan every year to boost China's electric car industry, Xinhua reported.

Ole Hui, a Hong Kong-based analyst at Mizuho Securities Asia, said he could not see a compelling commercial argument for electric vehicles in the mainland market in the next year or two.

'BYD's e6 is priced at 369,800 yuan,' he said. 'Even after deducting 120,000 yuan in government subsidies and the latest tax exemption for purchasing electric cars, it's still much more expensive than the company's f3 combustion engine model, which costs only 50,000 yuan.'

10%

The stake in BYD owned by US investment guru Warren Buffett, for which he paid US$232 million in October 2008

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