High-voltage systems reliably shut down in the event of an accident

Nov 2019

News & Campaigns

As part of a joint research project conducted by DEKRA Accident Research and traffic accident researchers at the University Medical Faculty in Göttingen, a Renault Zoe and three Nissan Leaf vehicles underwent crash testing at the DEKRA Crash Test Center in Neumünster. The tests, which involved deliberately crashing the cars into a post, were designed to simulate a range of scenarios involving collisions with a tree. The tests were conducted at speeds far greater than those normally applied in standard crash tests. The accident researchers concluded that, in terms of safety, the electric vehicles they tested equal conventionally powered vehicles. In three of the four crash scenarios, the experts initiated a side-on collision with the post – the Renault Zoe at 60 km/h and the Nissan Leaf (production series 2010-2017) at 60 and also 75 km/h. In an additional, fourth scenario, a Nissan Leaf underwent a head-on collision at 84 km/h.

“The damage patterns from the crash tests are comparable to those of conventionally powered vehicles,” says DEKRA accident researcher Markus Egelhaaf. “The high-voltage system in the electric vehicles was reliably shut down during the crash. And despite the fact that the drive battery was severely deformed, no fire broke out.” Fundamentally, the expert said, the chances of surviving especially a side-on impact with a tree would be very slim at those kinds of speeds. “But that applies to all cars, regardless of their drive system. The major manufacturers of series-production electric vehicles have reached at least the same level of safety as combustion-engined cars.” Not for nothing did the two models tested achieve the maximum of five stars in the Euro NCAP rating. “Our tests confirm that no one need feel any less safe in an electric car than in a conventionally powered car.”

The goal of the research project is to optimize the process of rescuing occupants from cars involved in accidents. So the crash tests were followed by a series of experiments to determine the most effective methods and tools that the rescue services can deploy to free occupants from cars. In response to regular reports of difficulties extinguishing burning drive batteries, a new extinguishing system – the extinguishing lance – was among the equipment tested. If sections of a drive battery do happen to catch fire, firefighters can insert this lance directly into the battery housing. “This means that firefighting takes place inside the battery, preventing the fire from spreading to other battery cells,” says DEKRA accident researcher Markus Egelhaaf. “This method appears to offer potential, but further research is needed to establish just how effective it really is.”

Share page