PANIC IN THE USA – The news arriving from overseas does not seem reassuring at all: according to the New York Times the lithium battery fires in the first 11 months of 2022 there were 87 more cases in New York City than in 2021 with a tragic toll of 6 deaths and 140 injuries. The New York Fire Department stated that “the batteries and chargers have serious security risks firefighting. They shouldn’t be used indoors because most apartments don’t have fire extinguishers like sprinklers and home furnishings are highly flammable”. These first responders report that these fires are often caused by damaged, malfunctioning or aged batteries or by inappropriate chargers overheating the battery, which happens very often in ‘lightweight’ electric scooters and two-wheelers. There are even plans to propose to the Government a ban on introducing bicycles and electric scooters into buildings.
DATA FROM CHINA – London firefighters are also sounding the alarm after a spike in fires caused by “bicycle and electric scooter batteries non-originals also intended for modified vehicles”. The alarm was triggered in July (always during the heat, therefore) and the London Fire Brigade website says verbatim: “we know that lithium-ion batteries are subject to failure if incorrect chargers are used and this can be a factor which in some cases contributes to fires. We have also noticed many of these incidents involving batteries that have been purchased over the internet from unofficial sellers and may therefore not suit you correct safety standards. Our advice is to always use the correct charger for the product and buy an official one from a reputable seller. It is also important to avoid shocks to the batteries, both during use and while being transported as this increases the possibility of damage to the cells, which facilitates fires.”
Other data are provided by the Beijing Institute of Technology and concern only the electric cars. According to these statistics, most of the fires (66%) occurred between May and September and therefore in the hottest months of the year. Out of 86 electric vehicle fires examined, 27.5% started during recharging, 38.5% while parked while the rest started again while driving, after an accident and for unidentified causes in 7 cases. China’s huge fleet of electric cars – 6 million units, or 36% of the world’s total – leads to an average of 7 fires a day, 640 in the first quarter of 2022.
THE RECORD OF FLAMMABILITY – Other numbers come from AutoinsuranceEZ, a US insurance comparator, which compiled numbers on vehicle recalls and data provided by the National Transportation Safety Board and the Bureau of Transportation Statistics. It is clear that it is easier to see a conventional car on fire than an electric car as electric vehicles are still not widespread. A sensible comparison relates fires to the number of vehicles sold and the data thus found shows that the primacy belongs to hybrid vehicleswhich have 3,474 fires per 100,000 units (remember the recall of the Fisker Karma who the news). Conventional automobiles log 1,529 fires and electric ones only 25 fires per 100,000 specimens: The Hyundai Kona had a recall for these, (who the news). In any case the batteries are the main suspectsas recalls in the US for fire risk in 2020 are polarized on battery pack defects for electric and hybrid cars while conventional ones range from short circuits to ABS defects to fuel leaks.
OVERWORK FOR THE FIREFIGHTERS – The burn of the lithium-ion batteries in electric cars they are therefore less frequent (they are much more advanced than those of bikes and scooters), but much harder to turn off compared to fuel fires and most firefighters are not very familiar with these types of fires. It can also happen that even when an electric vehicle fire seems extinguished it will flare up again, making it all the more necessary for firefighters to be trained to put out fires in hybrid and electric vehicles.
The curse of lithium-ion batteries is the thermal runawaythat self-sustaining thermal runaway when an excessive increase in temperature causes the liquid electrolyte to ignite, which is highly flammable. It therefore seems advisable to charge electric cars outdoors or in airy places and in compliance with a 2021 regulation, suggested by the firefighters, which concerns the garages in which electric, hybrid and hydrogen vehicles are hospitalized. There situation will improve a lot with the lithium-iron-phosphate batteries, already on the market, to finally become calm with the very promising solid-state ones.
