Electric bicycles, which environmentalists and Democratic lawmakers have touted for their zero-carbon output, are facing increased criticism over the rising number of tragic incidents involving their batteries.

According to the National Fire Protection Association (NFPA), so-called e-bikes are powered by lithium-ion batteries which are prone to fires or explosions. And as e-bikes continue to become more popular — the global e-bike industry is expected to grow nearly 200% to an estimated value of $118.7 billion by 2030, according to Allied Market Research — more cities nationwide are facing rapidly-increasing numbers of battery fires.

"The majority of lithium-ion battery fires that fire departments across the country are dealing with involve these micromobility devices," Matthew Paiss, a technical advisor in the Battery Materials & Systems group of the Pacific Northwest National Laboratory, told the NFPA Journal last year. 

"With something like an electric vehicle fire, you may be able to let it burn on the side of the road," he added. "With these, though, they may be in homes and high-rises, so fire departments have to engage. It’s a problem we need to address."

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Burned E bikes in NYC

Several e-bikes and lithium-ion batteries are seen strewn on the street as New York City firefighters fight a nearby fire. (FDNY)

While most cities don't officially track e-bike fire and battery fire-related injury data, New York City officials have recently shared such information as part of a campaign to inform residents about the dangers posed by the devices.

In 2022, e-bikes were responsible for an estimated 220 fires, up more than 100% year-over-year, and six deaths, according to the New York Fire Department (FDNY). Already this year, there have been 59 fires, more than three dozen injuries and five deaths in New York City as a result of e-bike battery fires.

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"These are incredibly dangerous devices if they are unregulated or used improperly," New York City Fire Commissioner Laura Kavanagh said during a public safety in February. "They show an enormous amount of fire when they catch fire — they often present an immediate inability to exit one's room or one's apartment or one's home."

"We're going to come at this from every angle of enforcement, but also want to do community outreach and will be in every community working with every stakeholder," she continued.

In the most recent example of a catastrophic fire from an e-bike battery, two children were killed Monday in Queens, New York. FDNY Chief of Department John Hodgens said that, while firefighters arrived to the scene quickly, the violent nature of lithium-ion battery-triggered fires makes it harder to quell. 

Eric Adams in January 2023

New York City Mayor Eric Adams has made addressing e-bike fires a priority of his administration. (Lev Radin/Pacific Press/LightRocket via Getty Images)

In another example, an e-bike fire in a Manhattan high-rise building late last year injured at least 38 people, The New York Times reported at the time. Another fire, in January, was triggered by an e-bike at a New York City daycare center, critically injuring one child and harming two others. 

As part of the city's efforts to combat the increasing number of incidents, in March, Democratic Mayor Eric Adams signed five bills to regulate the types of lithium-ion batteries sold in the city.

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"Today, we are supercharging safety for all of our e-bikes and e-scooter users," Adams said.

Other cities including Los Angeles, San Francisco, San Diego and Miami have also seen major fires from e-bike batteries.

And the U.S. Consumer Product Safety Commission issued a letter in December to more than 2,000 e-bike and e-scooter manufacturers and importers, urging them to ensure their products comply with voluntary safety standards, threatening legal action. The federal agency said it had received reports of fires and deaths from the product.

Rep. Adam Schiff, D-Calif.

Rep. Adam Schiff, D-Calif., said last month that e-bikes are a "phenomenal way to traverse our communities." (Drew Angerer/Getty Images)

"As you may be aware, in recent years there has been a rise in fires and other thermal events involving micromobility products—including e-scooters, self-balancing scooters (often referred to as hoverboards), e-bicycles, and e-unicycles," CPSC Office of Compliance and Field Operations Director Robert Kaye wrote.

"I urge you to review your product line immediately and ensure that all micromobility devices that you manufacture, import, distribute, or sell in the United States comply with the relevant UL standards. Failure to do so puts U.S. consumers at risk of serious harm and may result in enforcement action."

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The warnings about e-bike safety come as Democratic lawmakers continue to push the product as a key part of their climate agenda and effort to decarbonize the U.S. economy.

Last month, Reps. Jimmy Panetta, D-Calif., Earl Blumenauer, D-Ore., Mike Thompson, D-Calif., and Adam Schiff, D-Calif., introduced the Electric Bicycle Incentive Kickstart for the Environment Act which would provide Americans with an up to $1,500 credit on e-bike purchases. Sen. Brian Schatz, D-Hawaii, introduced companion legislation in the Senate.

"By incentivizing Americans to own and use e-bikes, we are allowing them the chance to help improve the quality of life in our communities and tackle the climate crisis in our country," Panetta said.

"Electric bikes are a phenomenal way to traverse our communities, combining the beauty of the outdoors with the ease and benefits of sustainable transportation," added Schiff.