Selasa, 02 April 2013

Big blow for battery R&D

TOO HOT TO HANDLE: Mitsubishi has suspended work on the electric Outlander and i-MiEV electric car while it sorts out an over-heating battery.
FEW readers of The Witness are old enough to remember when electric cars outnumbered cars with engines that relied on exploding the fuel inside a cylinder or two in order to get the wheels turning.
This was, however, the state of transport at the end of the 1890s, when many people shuddered at the thought of driving an “infernal combustion engine”.
The infernal combustors however proved more reliable and oil was being found everywhere, which soon saw the demise of the electric car industry as “ice” engines started to rule.
High oil prices, which oil guru Leonardo Maugeri said should cost about $70 per vat of Brent crude according to all the laws of supply and demand, has however started to drive people back to electric vehicles — or evees.
To date, the main problem in flogging evees is their batteries, which give about a quarter of the range of a typical fuel combustor.
Battery technology has however been improving every year with vast funds invested to develop units that can rival the range of a fuel tank.
This progress has now received a major blow, with Mitsubishi Motors Corporation last week announcing it had suspended production of its Outlander PHEV crossover and a variant of its i-MiEV electric car.
The website Electric Cars News reports that one lithium ion battery melted at a dealership and another caught fire in an assembly plant. Mitsubishi said faults were detected in two more vehicles. Mitsubishi also has suspended sales of both plug-in electric vehicles in Japan.
The batteries involved in the incidents were made by Lithium Energy Japan, a venture between G.S. Yuasa, Mitsubishi Motors and Mitsubishi Corp. Company investigators are working to identify the cause of the problem.
The incidents are the latest involving the Kyoto-based company’s batteries as U.S. and Japanese authorities probe the cause of overheated units that grounded Boeing’s Dreamliners in January.
The battery in the i-MiEV caught fire at Mitsubishi Motors’ Mizushima plant in Okayama Prefecture on March 18 when it was being charged during a test before installation in the vehicle.
Although the battery and cable were charred, no one was injured.
The Outlander PHEV battery, which was taken apart, showed signs of a short circuit in the interior wiring. When the battery pack was examined by the supplier, it was found that one of the battery pack’s 80 cells had overheated, melting adjacent cells.
The 80 cells in the drive battery pack are divided and set into three blocks within the drive battery pack. In the past, defective batteries were discovered on the same production line after impurities became mixed in the battery interior. Drivers have been advised not to recharge their Outlander plug-in hybrids through its plug.
They should also turn off the electric-only drive mode and disable the function that allows the engine to recharge the battery while driving. The Outlander PHEV, sold only in Japan, is scheduled to arrive in the U.S. next year.
The battery glitch is not expected to delay the U.S. launch.
Mitsubishi has yet to determine the cause of the problem but hopes to restart production within weeks, Koketsu said.
The Outlander PHEV went on sale in Japan on January 24 and Mitsubishi has sold 4 000 units.
That is nearly double the total of the standard gasoline-only Outlander, which has sold 2 500 vehicles in Japan since it went on sale here in October.
All of the 4 000 Outlander PHEVs sold so far could potentially be affected by the problem. The i-MiEV and a commercial vehicle variant called the Minicab come in two trim levels. The upper trim, which gets a bigger, more-powerful battery, uses the Lithium Energy Japan power pack. The lower trim uses a less-powerful battery made by Toshiba. Mitsubishi has halted production of only the vehicles with the Lithium Energy Japan-made batteries. The Toshiba batteries apparently are fine.
Mitsubishi has sold 15 000 i-MiE­V electric cars, since the model’s debut in July 2009.
About 1 300 were sold in the U.S. Mitsubishi has sold an additional 4 000 Minicab EVs, all in Japan.
Through February of this year, Mitsubishi sold 1 210 i EVs, including 600 in the U.S.
(Additional reporting by Electric Cars News.)

Tidak ada komentar:

Posting Komentar