I thought that the media was a little over the top with reporting every electric car fire.
Little did I realise just how blown out of proportion it was:
"…electric vehicle battery fires are rare. Indeed, the available data indicate the fire risk is between 20 and 80 times greater for petrol and diesel vehicles. "
The only thing to consider is that EVs have the possibility to catch fire when they are “passively” sitting unattended in your garage under charge, whereas liquid fuelled vehicles are more likely to catch fire in active use when everything is hot and things are being pumped around and someone is at the controls that can notice what’s going on and take immediate action.
So a petrol car can sit in the garage with the ignition off and very little is happening electrically (or chemically).
An electric car will be sitting in someone’s garage getting 5+ kW pumped into it for 3 to 10 hours overnight, every night. That’s a lot of energy getting manipulated via charging circuits and going into a large box of reactive chemistry in the car.
Now all that needs to happen is that quality components are used and electrical standards are followed and some practical things like interconnected smoke alarms are used. In Australia that’s mostly par for the course so it’s not a huge concern.
But the risk of a house fire in the wee small hours is definitely increased. Doing a quick thought experiment, you can pull a tiny chance out of thin air, like “an EV (or it’s charging system in the home) will catch fire while charging overnight once every hundred million times” and say, “imagine if there are a million electric cars in Australia”, and the net result is someone’s house burning down every three months. The media will be all over that shit if that happens, so car manufacturers and standards bodies have to really work at making that risk almost unimaginably tiny.
You know that petrol cars have electrical systems and batteries too, right?
Electrical issues are one of the bigger causes of petrol vehicle fires, and they don’t need the engine to be running. Those vehicles also have a large amount of dangerous chemistry inside them, but that’s somehow not a problem.
I’m an auto electrician by trade and I have been for 30 years. I do happen to know quite a bit about wiring on motor vehicles.
The difference I was highlighting is that a petrol/diesel vehicle parked with the ignition off is basically passive. It’s very rare for a switched off fossil fuelled car to catch fire by itself after a few minutes have passed since you’ve turned it off. Fuel is shut off, nearly all circuits are off, anything still actively powered at that point draws milliamps and will be protected by fusing in the 5-10 amp range , and any spontaneous electrical faults (from eg rats gnawing wiring) will be contained as a result. Critical high current wiring for your starter is routed away from points where it can short out if disturbed by said rats, your alternator wiring is protected by fusible links, and finally, your 12 volt battery has a quite limited capacity (in the 0.5-1kWhr range, if we want to compare it to an EV).
And then you have an electric vehicle which when “off” in your garage will have at least several kilowatts of power flowing through it from a high capacity mains circuit and a wall charger full of electronics. This goes on for many hours to charge a 50 to 80 kWh battery in your car while it is completely unattended and you’re asleep. A battery that is designed to put out a hundred-plus kilowatts when you stomp on the go pedal , and so is fused appropriately for that kind of current.
Of course it will also have protections, but the fact of the matter is that it’s a fundamental change in the operation of your vehicle. Now instead of being “turned off” overnight, a lot of high power things are occurring. The risk of a failure is higher simply because things are actively happening. Your car is active while you’re driving it just like a petrol car is, but now it’s also very active while it’s parked overnight.
Think of all the times in your last 30 years that you have seen an amateur Auto Elec (either a qualified mechanic, panelbeater or backyarder) that has royally screwed the electrical system.
Now think about all the times you have had a Car or Caravan that was worked on by one of your competitors.
There has to be public awareness that only EV-qualified auto electricians should be even thinking about touching an EV, especially after what happened at Thrifty Car Rental at Sydney Airport.
The 12V battery has a low capacity, but it has a very high power output - it has to, to be able to turn an engine over. It’s also quite close to a lot of flammable fluids.
You’re putting 5kW into an EV, but that’s a system designed for 150+kW of power. They don’t even get warm.
Tell me something I don’t know. How about you have a good look at my post again, read the very first line, and then rebut some of my actual points.
Simply put:
There are more points of failure and associated risks in an active high power charging circuit in an unattended EV parked overnight versus a fossil fuelled car in the same situation. Those failures are managed by good engineering and QA during assembly and install. Do we have good engineering and QA right now in our nascent EV market in Australia? We should but we won’t really know until the size of the EV fleet in Aus gets large enough to bring any issues to light.
The risks are miniscule, but to claim that an EV on charge presents less risk than a similar fossil fuelled vehicle parked overnight is laughable.
Bring on solid state batteries!
"Solid-state batteries address the safety concerns of traditional lithium-ion batteries by replacing the flammable liquid electrolyte with a solid counterpart, virtually eliminating the risk of fires and explosions.
Solid-state batteries have superior characteristics compared to lithium-ion batteries, such as higher energy density, longer lifespan, and faster charging. They also do not require additional safety features, making them lighter and more efficient for electric vehicles."
I wish there were more coming next year instead of 2028. 2028 is currently the forever “5 years away from production” in research lol
Maybe, but there’s still a lot of energy in them and if things go wrong that energy can be released. They’re probably an improvement but good standards of manufacturing etc. Are still important