(Corrects paragraphs 4 and 7 to say company found excessive voltage, not pressure, and in paragraph 5 deletes word “erosion”)
By Sophie Knight
TOKYO, April 10 (Reuters) - Mitsubishi Motors Corp will extend its production and shipment stoppage of its Outlander plug-in hybrids until it finds the cause of an overheating lithium-ion battery in one of the vehicles, the automaker said on Wednesday.
The company stopped production and shipments in late March, as cutting-edge battery technology faces heightened scrutiny after problems with batteries in Boeing Co 787 Dreamliner jets.
Batteries on the Outlander plug-in hybrid are supplied by a joint venture called Lithium Energy Japan, owned by Japan’s GS Yuasa Corp, Mitsubishi Corp and Mitsubishi Motors. Kyoto-based GS Yuasa is also the battery maker for Boeing’s Dreamliner.
Ryugo Nakao, managing director of Mitsubishi Motors, told reporters there were two other cases in which Outlander batteries had short-circuited and excessive voltage was detected: one where a customer in Tokyo could not start the vehicle, and another where a car in a dealership in Gifu prefecture would not charge properly.
In the first case, the battery also short-circuited and emitted a strange odour, he said, adding that company tests found that the resin had melted.
In a separate case, a lithium-ion battery fire in a i-MiEV electric vehicle at a Mitsubishi factory may have a similar cause to the problems in the Outlander battery, but Mitsubishi had been unable to confirm the exact cause in either case, Nakao said.
Mitsubishi Motors was exploring the possibility that the batteries were dropped during processing which may have led to excessive voltage, he said.
The executive could not say when the automaker will resume production because it will not do so until it has found the cause. While the company aims to finish the investigation by the end of April, Nakao said they could not confirm when it would be completed.
Mitsubishi Motors has sold 4,000 Outlander plug-in hybrid cars to date and has received 4,000 more orders. The vehicle is only sold in Japan, although it plans to sell the hybrid in Europe starting in July.
By end-February, it had sold 8,400 i-MiEVs in Japan and 6,600 overseas. (Writing by Dominic Lau; Editing by Daniel Magnowski)