GM’s Volt, a plug-in electric hybrid, earned a mark of “acceptable” in the Insurance Institute for Highway Safety's electric car crash test.

(Bloomberg) — General Motors Co.’s Chevrolet Volt passed the U.S. insurance industry’s toughest frontal crash test, while Nissan Motor Co.’s battery-electric Leaf couldn’t make the grade.

GM’s Volt, a plug-in electric hybrid that gets an energy-equivalent of 98 miles per gallon when running in battery mode, earned a mark of “acceptable,” the Insurance Institute for Highway Safety said today. The Leaf was rated “poor.”

This is the first time the Arlington, Virginia-based safety group rated electric cars on how well they protect drivers and passengers in simulated crashes. The IIHS tests on gas-powered vehicles have been influencing consumer purchases and getting auto manufacturers to improve safety since 1995.

The electric cars were part of a larger group of small cars run into a barrier meant to simulate a tree, telephone pole or other car, crushing about one-forth of the car’s front end. The test is tougher than U.S. government’s National Highway Traffic Safety Administration head-on crashes or other IIHS tests, the group said.

For an “acceptable” or “good” rating, cars have to be engineered to preserve space around the head and torso, have seat belts that keep a driver from pitching too far forward, and plenty of air bags to mitigate crash forces.

“Electric vehicles have a unique challenge in the small overlap test because of their heavy batteries,” said Joe Nolan, the institutes’s senior vice president for vehicle research. “The Volt performed reasonably well.”

C-Max Hybrid

One other gasoline-electric model tested, Ford Motor Co.’s C-Max Hybrid small, four-door wagon, matched the Volt’s “acceptable” rating. The Volt earned IIHS’s highest rating, “Top Safety Pick +,” for good results in four other crash tests and for making a frontal crash-prevention system available.

Test results for other small cars were mixed. Bayerische Motoren Werke AG’s Mini Cooper Countryman got a “good” rating, the best score in the current group. Mazda Motor Corp.’s 5, a four-door hatchback, was rated poor — one of the three worst-testing small cars.

Overall, 13 of 32, or 41%, of the small cars tested by the insurance group in recent years earned “marginal” or “poor” ratings.

In testing the electric models, technicians wore rubber boots and gloves and were tethered to a pole, so they could be pulled away in case of fire or shock after the crash. No incidents were reported.

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