Why EVs Typically Ace Rollover Crash Tests

They're relatively heavy, and they carry most of their weight down low.

Ronan Glon | 

Jul 3, 2024 | 3 min read

Mercedes-Benz

The full-size Ford F-150 Lightning electric pickup and the compact, internal-combustion Volkswagen Jetta sedan share a surprising statistic: They have about the same rollover risk. Here's how EVs use their weight to their advantage to keep all four wheels on the road.

Volvo

What Is a Rollover Test?

Sometimes called a moose test, one type of rollover evaluation is typically performed by driving relatively fast in a straight line and then suddenly making an evasive maneuver.

Don't try it during your commute home from work. This test is performed by professionals on a closed track to evaluate how a car handles and how well its electronic stability control systems work.

Other types of rollover tests, such as the sandpit test, are usually done in a lab. That test involves pushing a vehicle sideways onto a strip of sand to simulate an accident in which it skids off the road.

Volvo

What These Tests Mean in the Real World

While you're unlikely to encounter a moose in, say, Florida, skidding off the road can happen anywhere. Picture this: You're cruising along an interstate at a comfortable 60 mph when a deer or other animal darts across the road. Swerving to avoid it destabilizes your car, which could roll and crash if it loses grip.

Carmakers analyze the data gathered during crash tests and use the findings to build safer cars. These lessons were particularly important in the 2000s with the increased popularity of high-riding SUVs and crossovers, which have a higher center of gravity than sedans and are therefore more likely to roll over.

The spike in rollovers involving SUVs led the National Highway Traffic Safety Administration (NHTSA) to mandate a warning label.

Why Are EVs So Surefooted?

One of the less-heralded side effects of electrification is a significant improvement in rollover safety. In 2018, for example, the NHTSA had a difficult time putting the Tesla Model X on its roof during a sandpit rollover test. The SUV aced the test and earned a five-star safety rating. It's not alone. EVs in general are hard to roll.

The reason has to do with a key feature nearly all EVs share. The average EV uses a 1,000-pound battery pack that is usually installed under the passenger compartment. That makes EVs much heavier than comparable gasoline-powered models and also gives them a lower center of gravity. More weight positioned down low makes EVs less likely to tip over.

For example, the Ford F-150 can be had as a gasoline-powered model or as the electric Lightning. Both earned four out of five stars in the NHTSA's rollover test. However, the gas-burning truck has a rollover risk of 19.1% while the electric model has a rollover risk of 12.7%.

The first figure is typical for the segment. The Chevrolet Silverado and the Ram 1500 posted 19.1% and 19.8%, respectively. The Lightning's figure is more in line with that of a smaller car. The National Highway Traffic Safety Administration pegs the Kia Forte's rollover risk at 10.7%, the Volkswagen Jetta's at 13%, and the Toyota RAV4's at 15.5%.

Ronan Glon

Ronan Glon is an American journalist and automotive historian based in France. He enjoys working on old cars and spending time outdoors seeking out his next project car.