Electric cars continue to gain in popularity. But greater horsepower, new drive systems and increased use of driver assistance systems are creating new challenges for all road users. AXA Accident Research uses crash tests to highlight the various risks of electric-powered vehicles.
Today there are around 25,000 EVs on the roads in Switzerland. Although their number is still small, sales are rising rapidly. A representative survey by AXA of 1,000 Swiss shows that every third car driver can now envisage buying an EV in the future; this figure even rises to one in two drivers in the 18-24 age category. And electric car owners are unlikely to switch back, as 98 percent of them would choose an EV again, according to an exclusive survey of 340 electric car owners.
The rising number of electric vehicles on Swiss roads means that in the future they will be involved in more and more accidents. However, EVs differ from conventional cars in several ways, and this also has an impact on the incidence of accidents. This year AXA Accident Research used three crash tests at Dübendorf Air Base to highlight specific risks associated with electric cars.
Initial evaluations of previous claims figures show that the claims frequency of electric cars is generally comparable to that of other cars. However, there are clear differences by vehicle class. While small electric cars in the microclass/small vehicle category generate around 10 percent fewer claims than conventionally powered cars of the same vehicle class, the claims frequency for larger, powerful models in the luxury car/SUV category is around 40 percent higher. One reason for this is how the cars accelerate, according to Accident Research.
EVs accelerate very quickly and with the same force, regardless of engine speed. Maximum acceleration is available immediately, whereas it takes even powerful combustion engines a moment before they reach their maximum acceleration. This poses new challenges for drivers. Half of the drivers surveyed indicated that they had to adjust the way they drive when switching to an electric car due to the change in the way the car brakes and accelerates.
The consequences of rapid acceleration can be seen in AXA’s first crash test. The driver of an EV is driving along a highway and would like to accelerate only slightly before a right-hand bend. The car accelerates faster than he expects, forcing the surprised driver out of his lane on the bend and into the opposite lane. The oncoming car has no time to brake or swerve. The two vehicles collide head-on at approximately 70 km/h. Both cars are heavily damaged. Although the drivers are protected as much as possible thanks to their seat belts and airbags, they can both expect to sustain moderate to severe injuries.
Being able to drive a car doesn’t necessarily mean you can drive any car. In addition to traditional driving lessons, specific knowledge of individual vehicle types is also becoming increasingly important. With electric cars in particular, drivers first have to get used to the different way the cars brake and accelerate before they can safely use the vehicle.
An accident is just as dangerous for the occupants of an EV as it is for those in a conventionally powered vehicle. They undergo the same safety tests and are fitted with the same safety elements, such as a rigid passenger compartment and airbags. In a major collision, an electric car’s high voltage unit will also be disabled to ensure that the vehicle is no longer under voltage.
However, it is possible for the batteries to be damaged in an accident and cause a fire. Electric cars do not catch fire more frequently than other vehicles, but if a battery ignites, it burns very quickly, and the blaze is difficult to extinguish. In this case it is important to free the occupants of the car as quickly as possible and get them a safe distance away to protect them from burns and toxic fumes.
Another distinctive feature of electric cars is that they are very quiet. The engine in particular is almost silent when it is started, which means that a seemingly safe maneuver can also cause an accident, as the second crash test shows.
The driver of an electric car reverses from a parking space just as an elderly woman with a walker is about to pass behind the car. The driver doesn’t see the woman, and as the engine is silent, the woman hasn’t noticed that the car has started to move. She is knocked down to the ground by the car. Even though the primary collision with the electric vehicle appears harmless, the elderly woman may suffer extremely serious injuries from an unfortunate fall.
Since July 2019, EU law requires all new types of hybrid and electric vehicles to be fitted with an acoustic vehicle alerting system (AVAS) to protect pedestrians. However, there is no requirement for older models to be retrofitted. AXA recommends owners of silent EVs to voluntarily install a sound generator so that other road users can hear them.
Apart from rapid acceleration and silent driving, electric cars have another special feature: the increased use of driver assistance systems. Of course, all new vehicle models as well as EVs are equipped with assistance systems, but electric car drivers are generally more interested in technical innovations, know more about assistance systems and use them more often, according to a comparison of survey results of electric drivers and others.
99 out of 100 EV drivers whose cars are equipped with an autopilot say that they also use it more than half the time, or even all the time, most frequently on the highway and for longer distances.
AXA’s Accident Research & Prevention unit has demonstrated in different studies that driver assistance systems (DAS), in particular the emergency brake assistant and the electronic stability program (ESP), may help prevent accidents.
However, increased automation also means a heightened risk of drivers over-relying on technology. Today there are already various cases of accidents that are assumed or known to have been caused by a driver’s over-reliance on a system. The third crash test demonstrates what can happen in these situations.
The driver of an electric car is driving on the highway on autopilot which takes over the forward and sideways control. The driver relies on this technology and doesn’t pay attention – even though under current legislation he is required to concentrate on traffic at all times. The assistance system reaches the limit of its capacities at a highway intersection and immediately returns control of the vehicle to the driver. The driver has to react immediately, but because he wasn’t paying attention, he reacts too late. The car collides head-on at approximately 100 km/h into a crash cushion. Although it absorbs more energy than a concrete bollard, for example, the driver can be expected to sustain moderate to serious injuries from this severe impact.
Electric cars are generally just as safe as other vehicles. However, drivers and other road users must adapt to their special features and find the right way to handle them. The same applies to driver assistance systems. All systems currently available have to be monitored continuously. Although these systems act as a support, drivers must not become over-reliant on them so as not to endanger their own safety and that of others.