While EVs are slowly, very slowly – catching on would be exaggerated, people are starting to think about the finer points. For instance: Electric vehicles and plug-in hybrids are powered by high-voltage batteries of up to 400 volts, possibly more. What happens if one crashes and first responders have to attack the vehicle with power cutters? Will the responder die from electrical shock? This is a hot topic amongst first responders, right up there with dealing with explosive airbags, belt tensioners and other surprises.
Currently, each manufacturer publishes an individual Emergency Response Guide that tells them where to cut and where not. Easy to forget, especially with the paucity of EVs on the roads.
German automotive supplier Continental has developed a sensor unit for electric and plug-in hybrid vehicles which will immediately shut off the high-voltage battery in the event of a collision. Well, not exactly:
“The evSAT acceleration sensor is active in charge mode. It detects an accident and passes this information on to the battery management system which then shuts off the high-voltage battery,” Ibtimes was told by Dr. Axel Gesell, Senior Manager Platform Development Sensors & Satellites of Continental’s Chassis & Safety Division. “The major benefit of our product is that it prevents fire and rescue service personnel sustaining high-voltage injuries when coming into contact with vehicle metal parts or if they have to cut through the vehicle to recover accident victims.”
But what if the battery management system is dead already? And how do you know that the power is on or off? Current manufacturers of EVs have similar systems, one way or the other. None are perfect. According to greencarreports, automakers all tend to give variations of the same answer: “We’ve followed all the usual design standards on this new vehicle, and we’ll be offering training to national responder organizations that is disseminated down to their various members.”
One thing is for sure: EMS personnel will approach crashed EVs very carefully. Which may provide a niche for a certain market segment: Drug dealers. Police officers will search an EV with great caution. They are being trained not to pry apart the metal battery casing for the high-voltage battery, and not to mess with the battery itself. I will leave the rest as an exercise to the student.