E-bike battery explodes and torches Huntington Beach apartment; such disasters can be avoided, officials say

An e-bike had been charging for days in the first-floor apartment of a family of three in Huntington Beach when it exploded late one night this month. Flames spread rapidly and blocked their front door, forcing them to escape through a window.

Nobody was hurt, Fire Marshal Janice Van Mullem said. But the fire chewed through the outer wall of the apartment and scorched its interior, leaving its residents and several neighbors without a place to stay.

It may have started when the cells of the e-bike’s lithium-ion battery ruptured. That would allow chemicals normally kept separate inside of it to mix, resulting in a violent reaction.

“Batteries this size can go up like a rocket off of some of these e-bikes. This one could well have launched across their living room,” she said, later noting that the fire remained under investigation. “And you can’t put them out with water.”

But e-bikes aren’t inherently dangerous, Van Mullem said. She acknowledged they can be a convenient, environmentally conscious alternative to driving
Lithium-ion batteries power laptops, cellphones, electric toothbrushes and a long list of consumer devices. Catastrophic failures under normal use are generally uncommon.

“We want people to be able to have them,” the fire marshal said. “We just want to make sure they do so safely.”

It’s not entirely clear why, but firefighters in New York City have seen a dramatic rise in e-bike related fires in recent years. More than 200 such incidents resulting in six deaths were recorded there in 2022, as reported by the Associated Press.

Huntington Beach Fire officials don’t keep a tally of fires caused by lithium-ion batteries, but Van Mullem was aware of approximately three reported in the city in 2022. Of those, two possibly involved e-bikes.

Van Mullema said she and firefighters are closely examining fires related to the devices, especially as they grow in use as a mode of transportation.

She said most of the fire risk associated with e-bikes involves overcharging and faulty or mismatched electrical equipment. Explosive malfunctions like the one that wrecked the Huntington Beach apartment this month are mostly avoidable.

“We have a lot more say with residences and fixed structures,” the fire marshal said. “But when it comes to consumer products, including ones you’re going to ride all over town, a lot is going to depend on how an individual uses them.”

Batteries that are plugged in for too long generate heat that can damage them over time, potentially resulting in a leak between cells. That’s why it’s important to keep track of how long e-bikes charge and disconnect them from power shortly after they’ve been juiced up.

Van Mullem advised placing e-bikes that are charging in a garage or somewhere that isn’t occupied by people. If one has to be in a living area, owners should keep it away from sources of heat, potential fire hazards and any place where it might block an exit during an emergency.

Any piece of equipment that appears defective should be replaced with the same part provided by the manufacturer, Van Mullem said. And the brand of e-bike people purchase also makes a difference because not every company subjects their products to the same level of quality testing. She advised people to look for models that have been certified by Underwriters Laboratories.

“That’s probably the best way to make sure you’re getting something that should be safe to operate,” Van Mullema said.

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