E-bike fires have been making headlines lately as they should. Hundreds of them have occurred in New York City alone, linked to lithium-ion batteries used in mobility devices such as e-bikes, electric scooters, and hoverboards. These batteries also provide power to our laptop computers, cell phones, and cordless power tools.
Since the beginning of 2021, the US Consumer Product Safety Commission has received complaints of more than 200 events in which micro-mobility devices caught fire or overheated, resulting in the deaths of 19 persons.
E-bikes have risen in popularity, particularly in areas like New York, where they are used as the primary mode of transportation for making micro-delivery of food, parcels, and essential documents. Bike deliveries are speedier, which means that people in the so-called gig economy who make a profession delivering things might earn more money in a shorter period of time than if they attempted the same thing by automobile.
Even when parking for the smallest of cars is nonexistent, it is always feasible to locate a spot for a bicycle.
According to the Light Electric Vehicle Association, about 880,000 e-bikes were imported to the United States in 2021, which is double the amount imported in 2020 and three times the total imported in 2019, this means, more bikes on road which equals more fires, especially given the market is still relatively young and unregulated.
The fire starts because lithium may form small spikes called dendrites during operation. A short circuit occurs when such metal spikes come into contact with both the anode and cathode within a battery cell.
When this happens, the temperature of the battery cell can quickly approach 500o C. What happens next is referred to as “rapid disassembly” in the battery industry. Most of us would simply refer to it as an explosion.
The battery-powered micromobility sector is currently unregulated. Nobody knows how many lithium-ion batteries are in use, who made them, or what chemistries they employ. To bring some order to this chaos, the New York City Council passed several ordinances this month mandating that all e-bikes and other electric mobility devices sold, rented, or leased in the city be certified by Underwriters Laboratory, a safety organization that has been testing electric devices for over a century.
They also prohibit the sale of uncertified or used batteries. Retailers who violate the laws face fines of up to $1,000 per infraction hope this will bring such incidences under some control.
Reference- NPR story, Inside EVs, The Drive, Electrek, Twitter