Why Electric Cars Burn, Why It’s Probably Overhyped and How to Fix It

This tale is element of Plugged In, CNET’s hub for all matters EV and the long run of electrified mobility. From automobile evaluations to handy hints and the newest industry information, we’ve bought you included.

Lithium ion batteries do two issues seriously effectively: They ability a vast variety of devices, from small Z Flip phones to big Tesla Semi trucks, and they burn off properly. Here’s why they burn, how to keep that in perspective and what can be done about it. 

A perverse electric power source

Lithium ion batteries are somewhat perverse: They’ve invaded each and every corner of our homes, pockets and roads, but are also fantastic tiny fire-commencing kits. The moist remedy within them is very flammable at space temperature, the inner part of the battery known as the cathode is a supply of oxygen, and if the battery’s interior pieces get in touch with every other improperly they promptly heat up adequate to ignite the whole mess. It is really no question the Federal Aviation Administration and big delivery companies have quite stringent principles about carrying them.

Lithium battery shipping label

The transport labels on items with lithium ion batteries are very clear and stark.


Unsightly headlines

The large bang for lithium ion fireplace consciousness was the star-crossed Samsung Galaxy Note 7 that was banned from commercial planes in 2016. Any Tesla fireplace is a headline occasion, mainly since Tesla is generally a headline event, but Chevy Bolts final year were subject to a warning from GM to park them outdoors and absent from other cars when the company dealt with a battery fire glitch. And now electrical scooters and bikes are grabbing headlines as some multiunit properties ban them and the New York Town Council mulls new procedures that would ban the use of next-hand lithium ion batteries that often discover their way into indifferently developed merchandise. 

The Client Item Basic safety Commission has documented 25,000 studies of lithium ion batteries critically overheating between 2017 and 2021, not which includes vehicles and other motor vehicles, which are exterior its purview.

What starts off a battery fire?

Lithium ion batteries usually burn up when a single of four cases happen, according to investigation from the Occupational Safety and Well being Administration:

  • Incorrect charging. 
  • Extra draw on the battery.
  • Swelling and rupture of the battery due to very poor design, manufacturing or charging.
  • Bodily damage that will cause interior pieces of the battery to contact in an unmanaged way.

Unfortunately, most of these difficulties are outside of the user’s direct regulate Only the prevention of actual physical injury is a variable we can actively avert as end end users.

Lithium ion battery AA burning

Your normal alkaline AA battery will not do this, but lithium ion batteries are various (so you should not check out this).


Extinguishing burning autos

Qualified firefighters I have spoken to say that handling a burning EV is basically fairly reduced tech: They use sufficient (and often a whole lot of) h2o to comprise the over-all fireplace, enable the battery burn up by itself out and maintain the extinguished hulk of the vehicle isolated for days in circumstance remaining cells reignite, which is not unheard of.

There are oxygen-depriving fire extinguishing blankets that are utilized on car fires, but they have minor distinctive influence on an EV fireplace due to the fact the battery is in the bowels of the automobile and is a self-ample source of oxygen.

Fire extinguishing blanket

Fire extinguishing blankets only go so significantly with EV fires considering the fact that the battery releases its own oxygen offer and is deep in the belly of the auto.


Let’s provide down the temperature

Autos burn up all the time — about 500 instances a day in the US — and seldom are they electric car or truck fires. Apart from staying ubiquitous, fuel-engined cars are fireplace-starting up kits in their individual correct. If cars and trucks failed to exist still and I described to you a vision of cars with 20 gallons of gasoline slung underneath them in an exposed slim-walled metal tank that supplies a superior-force plumbing program snaking around an motor which is hundreds of degrees warm, you would send out me again to engineering college. But which is precisely what we travel.

Highway car fire

Cars and trucks burn up all the time. We only recognize it when they are electrical.

Getty Visuals

Electrical automobiles, on the other hand, have complex thermal administration techniques that gasoline autos have no equal of in their fuel offer system. And EVs are in the early times of convulsive improvement of these units, in which gas-engined vehicles have turned over most of their security stones. I’d wager on EVs getting safer in the medium and extensive time period. 

Lithium ion isn’t a single thing

“Lithium ion” is a catch-all identify that incorporates mixtures applying nickel, manganese, cobalt, aluminum, iron and other minerals and metals. A single of the a lot more interesting is a lithium ion variant referred to as lithium iron phosphate (LiFePo4). A modern FAA examination uncovered that this formulation creates the least expensive temperature rise of lithium ion types all through thermal runaway as effectively as possessing less propensity to ignite adjacent cells when a person catches.  

FAA test results for lithium ion burning behavior

Lithium iron phosphate variations of the lithium iron battery relatives (blue bars) tend to be significantly less harmful, in accordance to FAA flammability investigation.


Conveniently, lithium iron phosphate batteries are acquiring some thing of a minute correct now, with Ford among automakers that are embracing the formulation since it takes place to also be very good at dealing with a lot of cost cycles with very little capacity loss and employs a main substance that is more affordable, plentiful and less harmful, both of those chemically and politically. The downsides to lithium iron phosphate batteries is that they tend to be a bit heavier and have reduced strength density than some other formulations, necessitating much more battery to get the exact same range. But since most of us wildly overestimate the vary we want in an electrical vehicle, that may possibly be a moot position.

The other possible battery security breakthrough may well occur from reliable-condition batteries, which do absent with most or all of the flammable slurry inside of today’s lithium ion batteries. In accordance to a the latest research by the Sandia Countrywide Labs, strong-point out batteries do seem to be to be a great deal safer, while they will combust when pushed beyond sensible restrictions.

Battery fire safety issues since as goes our notion of it so goes considerably of our perception of safely applying and parking electric cars, scooters and bikes.