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Electric Car Fire Myth Laid To Rest, But Existential Risks Still Loom

Electric Car Fire Myth Laid To Rest, But Existential Risks Still Loom.

“We are definitely not seeing EV fires crisis. Tesla fires get a high profile. The most important thing-recognizing the difference between ICE and EV fires”

The risk of fire in an electric car has probably been exaggerated, while if your battery runs dry on the highway your only option won’t be to hoist the vehicle on to the back of a truck, but some scenarios do pose huge risks to the success of battery cars, like the extreme vulnerability of batteries to highly expensive failure because of damage.

The possibility that even modest ill-treatment can send a modern battery to the knacker’s yard, at huge expense and with crippling implications for insurance costs, would mean many ambitious plans for exponential electric car sales would have to be revisited.

But some reports of threats to electric cars are the result of media speculation with little data to show the extent of dangers.

Richard Billyeald, is Chief Technical Officer for Britain’s automotive, insurance, safety, security and engineering consultancy Thatcham Research. In an interview, he talked about real and imagined dangers posed by the oncoming electric car revolution.  He punctured some potential dangers but revealed others which might pose an existential threat to battery power by drastically shortening the life of by far the most expensive item on the electric car agenda.

As electric cars become more ubiquitous, a series of myths and unproven risks or disadvantages have built up. Spontaneous fires were said to be a threat, citing the example of laptop, tablet or phone fires. Extreme climate could unsettle batteries, including large temperature swings and elevated levels of dust and particulates. The need for high voltage fast charging stations was said to be a potential fire risk.

An article in the American Spectator “The Future of Electric Vehicles Is Highly Flammable” by Eric Peters earlier this year listed some disturbing possibilities, and said electric car batteries are very high voltage, typically 400 volts and 800 volts is becoming the norm and are fire prone. The process can allegedly trigger “thermal runaway” which looks more like spontaneous combustion to the layman. Fast charging, a crucial element if electric cars are to succeed, is supposedly going to raise fire risks.

Unique problems
Fire in an electric car poses a unique set of problems and doesn’t respond like a regular car fire as it often, relentlessly, reignites when appearing to have been extinguished. Damaged batteries can lead to fires, and this is big problem because an electric car is one vast battery compare with an internal combustion engine, where the fuel tank is small and located away from likely impact areas.

The media is full of videos of Teslas on fire, but the trouble is many of these dangers can’t yet be backed up by data to demonstrate a meaningful rate of fires in EVs, not least because the electric car business is still very young.

In the interview, Billyeald said it was impossible to say if electric car fires were taking place at a faster rate then ICE cars. More data was required.

“We are definitely not seeing a crisis of EV fires. Tesla fires get a high profile. The most important thing is recognizing the difference between ICE and EV fires and how to handle them. First responders or tow-truck drivers, repairers or anybody coming in contact with an electric fire has to understand they are different.   Billyeald said.

He did shoot down one rumor though. Electric cars, once stranded with an empty battery, were said to be impossible to tow and required a rescue truck with lifting gear. It turns out the problem was only a struggle finding neutral. When that’s found, towing is no problem.

According to Akkurate, battery specialists from Finland, fires may pose big problems and said climate conditions may be responsible.

“Of 23 fire incidents, 18 occurred in the mountains or coastal areas. It was concluded that these environments resulted in harsh conditions including large temperature swings, high humidity and elevated levels of dust and particulates which ultimately led to failure modes resulting in fires,” Akkurate said in a statement. 

Potentially volatile
Akkurate commented on the perceived problem of lithium-ion batteries in laptops and mobile phones.

“What makes this kind of battery potentially volatile is the high energy density of the batteries. The amount of power in each battery is large compared to its size and that makes them ideal for electric cars. But, if the small Li-ion batteries in phones are dangerous, how much more dangerous is the huge battery array in a car,” Akkurate said.

Akkurate didn’t respond to a request for an interview.

Billyeald wouldn’t comment directly on these propositions.

“From a technical point of view I can’t see big temperature swings leading to great fire risk, there might be plenty of other things at play. We are seeing more EVs on the road but they are still a very small proportion of the total. It’s very hard to draw very specific conclusions because we don’t have enough data yet but this will change in the next year or two,” Billyeald said.

Lithium-ion phones and laptops are similar to car batteries in terms of chemistry and fundamentals but the big difference is the high voltage and high energy density has to be managed differently with cooling very important for car batteries.

“High voltage vehicle batteries are managed a lot more closely than consumer electronic batteries even if they are fundamentally similar,” he said.

There can be so-called “thermal runaway” if the battery is damaged or is malfunctioning and the cells heat up and drive through the rest of the battery in a domino effect.

Swimming pool
“These fires, which won’t die down will self-perpetuate and fire fighters have to treat them differently because they can’t just spray water on the flames. They have to keep on putting on flame retardant and sometimes need to act drastically by dragging the vehicle into total immersion in a swimming pool-like area to prevent a runaway effect.

Is fast charging more of a fire risk and are fires under-reported?

“We don’t have the figures yet so I can’t say either way. The thing to do is avoid hyperbole on fires around Tesla and other EVs suggesting they are more prone to fires. If we focus on that we minimize the actual problems and we haven’t seen data yet from insurance companies suggesting there is a particular problem,” Billyeald said.

There is a potential problem which if not addressed could end up adding a huge existential-threatening cost element to electric car ownership; this is the propensity for only slight damage to batteries to render them useless. And batteries are a huge cost component in a battery electric vehicle (BEV). For instance, the battery in a Jaguar I-Pace costing roughly £70,000 ($100,000) is about half – £35,000. So, insurance costs are likely to be massive and could well price these vehicles away from any but the most high-income buyers. Given that prices are currently at least twice as much as a regular ICE car, this would be a hurdle that dooms electric cars to the margins. 

“The high voltage battery doesn’t fit into the usual insurance repair framework, where your car is damaged and goes off to be repaired and is ready within maybe 2 weeks. But if a relatively minor collision dents the battery or an airbag goes off causing the main fuse in the battery to be tripped to depower the battery, it will have to be taken out and returned to the manufacturer. There isn’t the expertise in the market for these batteries to be refurbished and returned, a replacement will be required so insurance claims will be much higher than for ICE cars,” Billyeald said.

Battery replacement?
This would also knock on the head a revived idea that the best way to recharge electric cars is to simply replace their batteries with another full one. The idea was pursued by Israeli company Better Place with Renault of France, but it crashed and burned in 2013. Renault revied the idea in May. Chinese EV company Nio also has a network of swap stations. The idea that electric car recharging could be as quick as ICE refuelling – you drive in, your almost exhausted battery is whipped and a full one put in – sounds compelling.

But if they are so delicate as to succumb to modest ill-treatment, with the replacement cost half the value of the car, the idea looks like a losing one, unless of course the price of batteries dives early and steeply. If the idea of battery swapping has much logic behind it because of the speed and ease, why wouldn’t swapping the whole car be the answer? 


 

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