"We apply the same high safety standards to all our products but the safety-related challenges may differ depending on the driveline and fuel being used. To us, electrification technology is another exciting challenge in our quest to build the safest cars on the market," says Volvo Cars' safety expert Thomas Broberg."It is understandable that a lot of questions about electrification safety are related to what will happen in an accident. But considering that less than one percent of our cars are involved in an accident during their life on the roads, we must adopt a more holistic approach, including all the aspects of day-to-day usage of the car," added Thomas Broberg.
Volvo is testing the safety of the electric cars with a range of safety scenarios. Monitoring the battery as well as protecting it effectively in a collision.
"A holistic approach and real-life traffic conditions are always the starting-point for our safety work. Based on our massive database with input from actual road accidents, we know where the focus must lie in everyday traffic conditions. The solutions we have developed for our forthcoming electric cars therefore take into account the situations that are unique to this type of car," says Thomas Broberg.
Information is obtained from the way the car is produced, used and serviced as well as how they are recycled. This will shape the development of the final production car.
Volvo tests safety in several stages, first the components and then the whole system and then the complete car. The car is first tested virtually via computer and then physically in Volvo's crash test centre.
"At present we are conducting tests at component level to see how the battery is affected by harsh braking and the subsequent collision. We are examining the results from several different angles. We have also carried out, for the first time, advanced full-scale crash tests to evaluate the technology used in electrically powered cars," reveals Thomas Broberg.
All of Volvo's existing safety systems will be available in the electric cars, but electric power adds a new danger which needs to be addressed. By analysing accident sequence phases engineers have developed a unique solution for the battery, as well as a way to keep occupants safe.
In normal driving conditions a system monitors the battery and makes sure it maintains correct voltage and operating temperature. Any deviation of either and the system shuts down.
The battery is well protected by steel beams and is separate from the crumple zones. If damage occurs to the battery resulting in gas leakage special evacuation ducts draw the gas out under the car. In the event of an impact sensors send information about the collision to the car's computer which shuts off the power supply to prevent a short-circuit.
After a collision the battery has a security cut out, works like a household circuit breaker. Shutting down and isolating the battery if the current travels in the wrong direction or if two cables are pressed together.
Fitted with a safety cut out for servicing allows mechanics to quickly and safely disconnect the power.
When the battery is at the end of its useful life Volvo or the battery manufacturer will recycle it.
"We may well see further down the line that cars powered solely by electricity can be made even safer than cars with combustion engines. We regard electrification technology as an exciting challenge - even from the safety viewpoint," says Thomas Broberg.