E-bikes, electric scooters and other micromobility devices have changed how many people move through cities. They're fast, convenient and can help replace short car trips or crowded subway rides. But as these devices have become more popular, lithium-ion battery safety has become a serious concern, especially in dense cities like New York.

I spoke with Robert Slone, Ph.D, senior vice president and chief scientist at safety science company UL Solutions. He told me what riders should know before buying, charging, or storing an e-bike, scooter or similar battery-powered rideable. 

Slone also explained how safer batteries, smarter certification and better rider habits are helping reduce lithium-ion fire risks, and why you should verify a product's safety certification before buying.

Charging location is everything

Slone's biggest warning: Don't charge or store your device in front of your only exit.

"If there is an issue, if there is a fire, there's not a lot of notice," he said. "These are not your typical fire in terms of dynamics. They're more like an explosion."

Many riders come home tired, park their bike near the door, plug it in and go to sleep. It's convenient, but it can also block the only way out if something goes wrong.

Slone warned against using aftermarket chargers or replacement batteries that weren't designed for the device. Even a bike that's been safe up to that point can become dangerous if paired with the wrong charger or battery.

"These systems are designed to work together," he said. "If you go aftermarket and start mismatching batteries or chargers, that is when we have definitely seen issues."

UL Certification, and why it matters

Many people focus on speed, range or price when buying an e-bike or scooter, but battery certification may be one of the most important safety features to look for. Slone said riders should verify whether both the bike and battery have been tested to recognized safety standards before buying, especially as uncertified batteries continue to play a major role in lithium-ion fires.

UL 2849 certification covers the e-bike's electrical system, while UL 2271 applies to the battery pack. According to Slone, the testing process includes overcharge testing, water ingress, humidity, vibration, drop testing, motor stress and checks to make sure the battery management system can properly stop unsafe conditions.

E-Bike fire statistics in New York

The good news: Safety is improving. Slone said New York's lithium-ion battery fire numbers have dropped sharply since the worst year of the crisis. The improvement has been helped by certification, better manufacturing and public education from groups such as the New York City Fire Department.

But certification claims also need to be checked. You can use UL Solutions' Product iQ search tool to verify whether a product has actually been tested and certified by the company. That matters because fake certification marks can mislead shoppers. UL Solutions redesigned its certification label with holographic security features to make counterfeit UL stickers harder to copy and easier to verify.

UL Solutions filed a public lawsuit last year against Fly-E Group over alleged counterfeiting of the UL Mark, and a settlement was reached.

For riders, the takeaway is simple: Don't cut corners. Buy from reputable brands, verify certification claims, use the charger that came with your device and never block your exit while charging.

As e-bikes and electric scooters get faster, smarter and more powerful, battery safety needs to stay part of the conversation.

Beyond the testing stage

UL Solutions says certification doesn't stop once a product passes testing. According to Robert Slone, the company conducts surprise follow-up inspections and pulls random production samples directly from factories around the world to ensure the products shipped still match the versions originally certified. 

"We don't want the golden sample," Slone said, referring to specially prepared units manufacturers could potentially present during scheduled testing. Instead, UL engineers perform unannounced spot checks at manufacturing facilities in regions, including China, Southeast Asia, Mexico and elsewhere. The goal is to verify that batteries, chargers and electrical systems continue to meet the same safety standards required during the initial certification process. If a product no longer complies, UL can suspend or revoke certification and halt shipments.

Slone noted that products don't necessarily need to be tested directly by UL Solutions to meet UL safety standards, as multiple OSHA-recognized labs are approved to perform the certification process. Other recognized labs, including Intertek, SGS, TÜV Rheinland, and CSA Group, can also certify products to standards such as UL 2271 and UL 2849 through OSHA-approved testing programs.

While many incidents included in FDNY's official numbers involve micromobility devices like e-bikes, scooters and other electric rideables, the category can also include hoverboards, laptops, power tools and other battery-powered electronics. Because of that, the above chart reflects the overall number of lithium-ion battery fires, not just e-bike or scooter fires. Also worth noting, the 2025 year-to-date figure of 87 fires is based on partial reporting and not a finalized full-year FDNY total.