Crash tests & electric cars: strong structures for safety
Audi Q8 e-tron: Power consumption (combined*) in kWh/100 km: 24.4–20.1CO₂ emissions (combined*) in g/km: 0
Information on fuel/power consumption and CO₂ emissions with ranges depending on the selected equipment of the vehicle.
Only consumption and emission values according to WLTP and not according to NEDC are available for the vehicle.
Audi Q8 e-tron: Power consumption (combined*) in kWh/100 km: 24.4–20.1CO₂ emissions (combined*) in g/km: 0
Information on fuel/power consumption and CO₂ emissions with ranges depending on the selected equipment of the vehicle.
Only consumption and emission values according to WLTP and not according to NEDC are available for the vehicle.
Hundreds of thousands of customers are totally excited about their decision to buy an electric car. But there are still a number of drivers who remain skeptical about
electric cars, even in 2023 – despite the fact that they are increasingly filling the streets in many towns and cities. One reservation that is often voiced concerns the topic of safety. What happens to the battery if there is a crash? Is the flow of electricity immediately interrupted? In the event of an accident, is there a greater risk of fire with an electric car compared with a vehicle powered by gasoline or diesel?
Crash tests
1
2 performed by independent organizations provide important parts of the answer to these questions: for example, the Audi Q4 e-tron
1 received the top rating of five stars in the Euro NCAP crash test
3, just as the Audi e-tron
2
4 did in 2019 as the brand’s first electric car.
Audi e-tron: combined electric power consumption in kWh/100 km: 28,4–21,7 (WLTP), combined CO2 emissions in g/km: 0 (WLTP). Information on electric power consumption and CO2 emissions in ranges depends on the vehicle’s selected equipment. The vehicle is no longer offered for sale.
Audi Q4 e-tron: Power consumption (combined*) in kWh/100 km: 19.4–16.2CO₂ emissions (combined*) in g/km: 0
Information on fuel/power consumption and CO₂ emissions with ranges depending on the selected equipment of the vehicle.
Only consumption and emission values according to WLTP and not according to NEDC are available for the vehicle.
Audi e-tron: Power consumption (combined*) in kWh/100 km: 24.3–22.0 (NEDC) | 26.1–21.7 (WLTP)CO₂ emissions (combined*) in g/km: 0
Information on fuel/power consumption and CO₂ emissions with ranges depending on the selected equipment of the vehicle.
The important thing about the Euro NCAP tests: “The criteria for our crash tests are basically the same as for vehicles with combustion engine and electric vehicles. With electric cars, however, more attention is paid to the inspections following an accident,” explains Michiel van Ratingen, Secretary General of Euro NCAP. “There is a concern with electric vehicles that the battery will be damaged in an accident and result in fire. Engineers working on electric cars therefore face additional requirements in relation to energy management, vehicle deformation and interruption of voltage following impact.”
Crash tests for more safety
The five-star ratings
1
are no surprise to the safety experts at Audi since the company has always considered vehicle safety to be a major concern and has also clearly formulated this requirement in its Corporate Regulations. As early as 1938, engineers at DKW, one of the founding brands of today’s AUDI AG, carried out systematic rollover tests with various DKW models in Colm near Potsdam – the first
crash tests in the history of the automobile. These were complemented by reproducible crash tests that took place on a purpose-built facility in the central Auto Union testing department.
“Our specialists perform thousands of crash simulations each year. Before the first real prototype is built.”
Today: “Each of our models, regardless of drive system, meets the high internal standards,” says Thorsten Adolph, expert for front and rear crashes in the Whole Vehicle Development department. “This involves a lot of know-how, hard work – not to mention significant computing power. Crash simulations are now an indispensable part of model development: our specialists perform thousands of crash simulations each year. Before the first real prototype is built.”
“We go the extra mile to ensure our vehicles offer very good protection. And we are delighted when we get such good results from independent crash test”1 2, says Michael Broscheit, expert for consumer protection at Audi. “Especially considering the skepticism that unfortunately still exists among consumers regarding electric cars. We have very high standards when it comes to safety, Audi invests a great deal – and that applies not only to crash simulations, but also of course when it comes to developing the individual components, especially with regard to battery cells.”
Audi battery testing center in Gaimersheim
“There are two major differences regarding the safety of an electric car compared with a vehicle with combustion engine,” explains Audi development engineer Sebastian Jäckisch.
“Firstly, it is important to really safeguard the high-voltage battery in the event of a crash. The battery consists of a stable housing that is designed to adequately protect the battery modules from damage even in a heavy collision,” explains Jäckisch (see infographic below). Audi has the necessary expertise for building this safety-relevant component itself – the company has been assembling the battery module in Brussels for several years now and the assembly of pre-production batteries for the next generation of electric vehicles is currently underway in Ingolstadt.
“And secondly, the risk of electric shocks has to be minimized. For this purpose, the high-voltage system is designed so that it is safe to touch. In other words, live parts are insulated and made inaccessible. At the same time, the high-voltage system is shut down after an accident in which the airbag is triggered and the voltage in the high-voltage system automatically reduced,” explains the engineer.
The quality of the battery cells is another important factor. The Premium brand group can rely in this respect on the know-how of its own battery testing center in Gaimersheim. Here, the individual cells and the battery system as a whole have to pass numerous intensive tests. The Audi experts conduct crash and overcharge tests, while the service life and mileage of several hundred thousand kilometers are reconstructed on test rigs. In this way, Audi is working to ensure a high level of possible product safety in all its electric models – all the way to the individual battery cell.
Audi Q8 55 e-tron: Power consumption (combined*) in kWh/100 km: 24.4–20.6CO₂ emissions (combined*) in g/km: 0
Information on fuel/power consumption and CO₂ emissions with ranges depending on the selected equipment of the vehicle.
Only consumption and emission values according to WLTP and not according to NEDC are available for the vehicle.
Audi Q8 55 e-tron: Power consumption (combined*) in kWh/100 km: 24.4–20.6CO₂ emissions (combined*) in g/km: 0
Information on fuel/power consumption and CO₂ emissions with ranges depending on the selected equipment of the vehicle.
Only consumption and emission values according to WLTP and not according to NEDC are available for the vehicle.
4 questions for ...:
An interview with Jochen Schäfer, external honorary consultant of the DFV (German Fire Services Association)
Mr. Schäfer, how is a battery fire extinguished and how does the process differ between electric cars and vehicles with a combustion engine?
Water is and clearly remains the best means of extinguishing a fire. The advantage: water is available almost everywhere, unlike firefighting foam, for example, which is used by the fire service to starve the burning fuel of the necessary oxygen. However, we need a lot more water in the case of an electric car than for a vehicle with combustion engine because we need to cool the battery after extinguishing the fire. This is the only way we can ensure as far as possible that other components do not subsequently catch fire again.
How do the responders know where to find these components?
Basically it’s not much different to the procedure for cars with a combustion engine: we secure the scene of the accident and the vehicles involved and check the use of rescue equipment such as cutters, spreaders or rescue cylinders. But there is one decisive difference compared with combustion models: to protect the passengers and the emergency responders, we have to be sure to work along the clearly marked high-voltage components during the technical accident rescue. This is not complicated, but it is necessary to ensure that live wires are not cut, for example, by rescue shears.
How do the responders know where to find these components?
A rescue data sheet is issued by manufacturers for their vehicles, whether electric or with combustion engine, which contains a precise description of all the information needed by the emergency responders. These rescue guidelines can be downloaded online or via app. Modern electric cars also issue an emergency call automatically to the nearest rescue center in the event of an accident. This also includes data about the vehicle, making it immediately apparent what model is involved.
Do you think there is an increased risk of fire in the event of an accident with an electric car compared with a vehicle with combustion engine?
Without question: no, not at all!
Biography:
Jochen Schäfer, M. Eng., is Managing Director of Defensio Ignis, a firm of experts & engineers in the area of fire safety, first aid and occupational safety in Linnich. He is also a commissioned fire safety engineer of the Mecklenburg-Western Pomeranian Chamber of Engineers, a publicly certified expert for preventive fire safety (FH) and according to DIN EN ISO/IEC 17024, a senior fire inspector and specialist fire service consultant to the German Fire Services Association (DFV).
