General Motors Co may redesign the battery for its Chevrolet Volt to address issues raised after federal officials opened a safety probe into the plug-in electric car, GM's chief executive said on Thursday.

We want to assure the safety of our customers, of our buyers, and so we're just going to take a time out, if you will, in terms of redesigning the battery possibly, Dan Akerson told Reuters Insider.

GM said on Monday it would offer loaner vehicles to about 5,500 Volt owners as it works with the National Highway Traffic Safety Administration on ways to reduce the risk of battery fires breaking out days after crashes involving the car.

(For the full Reuters Insider interview with Akerson, see http://link.reuters.com/fyw35s.)

The company also said it would not deliver the Opel-branded version of the Volt in Europe until its engineers and safety regulators had worked out how to deal with the 400-pound battery pack after any accidents.

The steps came in response to a decision last week by NHTSA to open an investigation into the safety of the Volt's battery pack. A lithium-ion battery pack in a Volt that had been through a crash test in May caught fire three weeks later at a test facility in Wisconsin, according to NHTSA.

In lab tests completed last week by U.S. safety regulators, a second Volt pack began to smoke and throw off sparks while a third battery pack caught fire a week after a simulated crash.

The probe has threatened the reputation of a vehicle that has been featured prominently in GM advertising as a symbol of the U.S. automaker's drive toward improved fuel economy.

It is a safe car, Akerson said. We just want make sure that there are protocols post-crash.

We want to make sure all the Ts are crossed, the Is are dotted, and no one has any question about the car long term.

He cited the Volt's top crash-test ratings as well as Thursday's announcement by Consumer Reports that the Volt ranked the highest among all models in customer satisfaction.

Consumer Reports said 93 percent of respondents who own the Volt would definitely buy it again, making it the highest-rated car in the nationally representative survey.

However, Consumer Reports pointed out that the Volt, which sells for $40,000, has not been in dealer showrooms long and the survey was conducted before NHTSA announced its probe.

GM executives have said that the Volt's battery pack would be safe during and immediately after any crash and that problems were not linked to any flaw in battery cells supplied by South Korea's LG Chem Ltd.

'STORM CLOUDS' IN EUROPE

Akerson also said GM is looking at more moves to fix its struggling Opel unit in Europe. While declining to go into details, he said the focus would be on boosting sales and cutting costs and could include shifting more production into Europe, possibly from Asia.

GM executives have said all options are on the table for money-losing Opel, suggesting to analysts that job cuts or plant closures could be options.

In addition, the European economy remains shaky.

We see serious storm clouds, if you will, on the horizon in Europe; a lot of consumer confidence has been eroding, Akerson said. There's a lot of uncertainty in Europe about the economy and whether it's going to go into recession.

He called Wednesday's announcement of steps taken by top central banks around the world to prevent a credit crunch among European banks a step in a journey that needs to be completed.

GM said Thursday its U.S. auto sales in November rose 7 percent, short of what some analysts had expected. Retail sales rose 15 percent, while sales to fleet, or corporate, customers, fell 14 percent to a level where Akerson wants GM to remain.

Akerson said he hopes to end 2011 with the Chevy Cruze small car taking the title as the top-selling car. He also cited GM's Buick brand, which is battling to outsell Toyota Motor Corp's Lexus in the luxury segment.

(Reporting by Ben Klayman and Paul Ingrassia; editing by John Wallace and Gerald E. McCormick)

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