The Dangers of E-Bike Batteries
As electric bikes become increasingly popular, there is an important question that must be addressed: what risks come with using e-bike batteries?
With all the recent news stories and reports of lithium-ion e-bike batteries catching fire or even exploding, it’s time to understand the real dangers and safety precautions we should take.
In this blog post, we will explore the potential risks associated with e-bikes and provide some tips for mitigating those risks. If you own or are thinking about purchasing an electric bike, read on to learn what you need to know about battery safety.
The pandemic saw a sudden and drastic increase in e-bike sales, but this newfound popularity has brought with it a host of problems. the most concerning being exploding batteries that have caused deadly fires. This is especially evident in New York City, where an e-bike battery sparked a fire at a Bronx grocery store on Sunday (March 5th, 2023) that injured seven people.
It’s the latest in a string of fires started by the lithium-ion batteries in electric bikes and scooters. They’ve caused at least 30 fires, 40 injuries, and two deaths in NYC this year as of Feb. 27, according to the New York Fire Department.
- Last year, they ignited 216 fires—double the amount of the year before—resulting in 147 injuries and six deaths.
The issue is due to the chemical nature of the lithium-ion cells inside the battery. If not adequately cooled or managed, they can overheat and quickly reach high temperatures which can cause them to explode and release hazardous material such as caustic smoke or burning plastics.
Fires caused by lithium-ion batteries can spread quickly and be difficult to extinguish
Lithium-ion battery fires can spread quickly and be extremely challenging to extinguish. In a matter of seconds, a fire caused by lithium-ion batteries can consume an entire room. Our research has found that the typical timeframe for such a fire to engulf a room is about 15 seconds.
Furthermore, the toxic fumes created from such fires can be hazardous to breathe in, making the fires extremely difficult for firefighters to extinguish. Therefore, consumers must be aware of the risks associated with e-bike batteries to remain safe.
Risk of injury or death if left unattended while charging
E-bike batteries carry a large risk of causing serious injury or even death if left unable to be monitored while charging. With an e-bike battery full of energy, overheating could result in a catastrophic reaction, often with devastating consequences.
Such batteries must be observed while they are being charged and should never be left unattended. Besides these dangers, additional instability can arise from mishandling and mechanical failure, requiring that risks be continuously assessed and acted upon with the utmost caution.
Difficulty in knowing when a battery has become faulty or is going to catch fire unexpectedly
While e-bikes have revolutionized urban transportation, the danger associated with their batteries is largely unknown. Unfortunately, it can be difficult for riders to know when a battery has become faulty or if it’s at risk of catching fire unexpectedly.
That’s why understanding precautions and safety protocols are so important. Even if you don’t feel that your battery poses a major threat, regular checkups and maintenance should be done regularly to ensure optimal performance and reduce the chance of an unforeseen issue arising down the line.
Taking these extra steps might just save you from a potentially dangerous explosion while also ensuring you get the most out of your e-bike, performance-wise.
Vulnerability of groups such as children, people with disabilities, and the elderly
By no means are lithium-ion battery-powered electric bikes a danger only to cyclists, but this vulnerability reaches far beyond.
Those most affected include people in vulnerable groups like children and the elderly where knowledge of the risk may be limited; similarly, those with disabilities that prevent them from being able to quickly dismount from an e-bike if an explosion were to occur can also be adversely affected.
One should never underestimate the potential destruction that could be caused during an e-bike battery explosion due to a lack of knowledge about the issue, so it’s important for everyone regardless of age or physical ability to remain informed and vigilant.
Source: cityandstateny.com
Inaccurate labels on e-bikes may lead consumers to believe they are safe
As the popularity of e-bikes continues to climb, consumers need to be aware that some models are falsely identified as safe. The inaccurate labels may give the impression that the batteries powering these electric bicycles will not explode or catch fire, but unfortunately, this is not always the case.
While safety warnings and regulations from manufacturers should explain the risks associated with using e-bike batteries, counterfeit products can often be difficult to differentiate from genuine ones.
This means that what unsuspecting buyers may think is a perfectly safe device could unexpectedly cause harm if their trust in the labeling is misplaced.
What can we do to solve the problem?
Bills to be approved that set new safety standards for electric micromobility vehicles instead of an outright ban
In response to the problem, some cities and states have proposed banning electric micromobility vehicles (most commonly e-bikes and e-scooters) altogether. But instead of an outright ban, bills have been proposed that set new safety standards for these vehicles.
These bills aim to address safety concerns while still allowing people to use electric bikes and scooters as a mode of transportation. The new standards include certification processes and other safety regulations that manufacturers must adhere to to ensure the safe use of lithium-ion batteries in these vehicles.
One of the main reasons why this legislation was necessary is due to the increase in reported incidents caused by the mishandling of lithium-ion batteries. These incidents include explosions, fires, and other accidents that can cause serious injuries or even death (as mentioned earlier).
By setting new safety standards, manufacturers will be required to produce electric bikes and scooters with safer lithium-ion batteries that are less likely to malfunction.
The positive impact this legislation should have on reducing the number of injuries, deaths, and damages caused by faulty li-on batteries cannot be overstated. By ensuring that manufacturers produce safer vehicles with more reliable batteries, people can feel confident using electric bikes and scooters without fear of injury or damage.
However, it’s not just up to manufacturers to ensure the safe use of electric bikes and scooters with li-on batteries.
Consumers also need to take steps in order to ensure proper storage and use of these vehicles. This includes storing them in cool, dry places away from direct sunlight or heat sources, using only chargers provided by the manufacturer, not overcharging them, avoiding extreme temperatures while charging or riding them, as well as regularly checking for any signs of damage or wear-and-tear on the battery.
In conclusion, bills approved that set new safety standards for electric bikes and scooters are a positive step forward for both safety and sustainability. They allow people to continue using these convenient modes of transportation while ensuring their safety on the road.
Manufacturers will be held accountable for producing safer vehicles with more reliable lithium-ion batteries while consumers can take steps towards ensuring proper storage and use of these vehicles.
Together we can make sure our e-bikes are both fun AND safe!
How to Avoid an Ebike Battery Fire? Follow These Crucial Steps!
Almost all modern electric bikes run on lithium-ion batteries. These batteries are found in many of our electronics, such as phones, laptops, and other e-vehicles.
Unfortunately, while this technology has numerous benefits, allowing a lot of energy to be stored in a small unit, it also brings a higher risk of fire if not handled appropriately.
Many high-profile e-bike battery fires have occurred in the past year or two, leading to the deaths of several people and injuries to many more.
Due to these incidents, there has been increased awareness about the dangers of lithium-ion batteries when mishandled or poorly made.
As a result, regulators are now pushing to implement laws that ban the sale of dangerous batteries and provide safe charging stations for owners.
This article will outline how e-bike fires start and what you can do to prevent them so you can stay safe and continue to enjoy your electric bike.
Why Are E-Bike Fires Becoming Frequent?
An explosion in the use of electric bikes over the past few years, especially in major cities, has led to many people trying to find cheap alternatives to buying, repairing, or tampering with the bike’s electronics.
Likewise, with more people using the technology, the sheer amount of these products in circulation will inevitably lead to more e-bike battery fires from mishandling.
What Is Causing E-Bike Battery Fires?
Lithium-ion batteries store lots of energy and are made up of highly flammable chemicals.
If the battery is damaged or overheats, the energy in the battery can ignite and cause a fast and aggressive fire that is hard to control. In addition, the chemicals that ignite in these batteries cannot be extinguished with water.
Most fatal fires occur when the battery is charging and unattended. There are several reasons that these fires occur. Thankfully, once you know what they are, you can take the appropriate steps to avoid them.
One of the most common causes of e-bike battery fires is overheating. This can occur if the battery is left to charge near a heat source or in direct sunlight.
If this happens indoors and the battery is beside other flammable materials, a severe and often lethal fire can spread rapidly through the building.
If a battery is damaged through an accident or after being dropped, the energy inside may become more volatile, increasing susceptibility to an e-bike fire if the battery gets even slightly too hot.
Off-brand batteries without certification by independent sources or subject to strict quality control are more likely to catch fire.
Likewise, charging your existing battery with a cheap replacement charger or the wrong brand can cause fires.
Tampering can also lead to electric bike fires. This includes penetrating the plastic case, taking it apart, or trying to modify the battery in any way.
How to Prevent E-Bike Battery Fires?
Again, preventing electric bike fires is possible if you follow care guidelines and best practices established by the manufacturer and regulators.
Charge the Battery Only When You’re Present
Most deadly e-bike battery fires occur when a battery is left to charge unattended. For example, leaving it overnight while you’re sleeping or stepping out of the home and leaving it plugged in.
Source: Huntington Beach Police Department
These fires spread quickly, so every second is essential to controlling them.
Only charge your battery when you’re present, ideally in the same room.
Use the Charger That Comes with Your E-Bike
Don’t use any third-party chargers or chargers of different electric bikes. If yours breaks, buy a replacement from the bike manufacturer or the e-bike system manufacturer directly. Double-check it’s the appropriate one before buying.
Source: London Fire Brigade
Charge the Battery Away from Flammable Materials
When you leave the battery to charge, place it away from flammable materials and objects that will ignite rapidly in the event of an e-bike fire.
For example, don’t charge it on the carpet, beside the couch, or on a desk full of papers or books.
Choose the Charging Location Carefully
Place your electric bike and charge your battery in an area away from exits so that you can quickly evacuate if an e-bike battery fire starts and you can’t control it with an extinguisher.
Never charge your ebike in a place that is located between you and the exit.

Look for Batteries That Have UL (Underwriter Laboratories) Certification
Quality control and certification are important for batteries as they guarantee a level of care in construction and design that means a lower likelihood of an e-bike fire (once you handle the battery appropriately).
Cheap off-label batteries typically don’t have these certifications or high levels of quality control.
Assess Your Battery After a Crash
The internal cells of a battery can become damaged in the event of a crash. This damage isn’t always obvious by looking at the exterior.
Give the battery a thorough examination if you crash your e-bike, and err on the side of caution by replacing it if there is any notable damage, as it could significantly increase the chance of an e-bike battery fire.
Don’t Use Off-Brand Replacement Batteries and Chargers
Again, off-brand replacements not explicitly designed for your e-bike are among the most common causes of e-bike battery fires.
Electric bike fires are uncommon in systems made by reputable manufacturers such as Bosch and Shimano, as quality control is extremely high.
Always replace old or broken components with those from the same manufacturer.
Charge in Fireproof Containers
A trick to minimize the chance of e-bike battery fires spreading if a battery does ignite is to charge and store it in a fireproof container or area. Examples include a BBQ grill, fire pit, ammunition box, fire blanket, metal trash can, or clay pot.
Lithium-Ion Batteries in E-Bikes and Other Devices Pose Fire Risks
The batteries, also found in phones, laptops, toothbrushes and other items, have caused about 200 fires and six deaths in New York City this year, fire officials say. Here’s what to know about safety.
A lithium-ion battery in an apartment with at least five e-bikes caused a fire in Manhattan this month that injured almost 40 people. The fire, which was one of 188 caused by lithium-ion batteries in New York City this year, led to warnings about risks associated with the batteries and ways to minimize them.
Lithium-ion batteries power devices in every corner of our lives, including phones, laptops, toothbrushes, power tools and electric vehicles. But many don’t know how to handle them safely or that they might start fires.
How do lithium-ion batteries work?
Lithium-ion batteries are rechargeable, last a long time and store a lot of energy in a small space. That has made them the most popular power source in electronic devices and vehicles, said Victoria Hutchison, a research project manager at the Fire Protection Research Foundation.
When a failing battery overheats, it can violently eject gas, projectiles and flames, then spread like a chain reaction to the other cells, she said.
Battery fires are quick and destructive.
Fires involving lithium-ion batteries have become more common in New York City: Six people died and 139 have been injured as a result of battery-caused fires so far this year, according to the New York Fire Department. Last year, the batteries were connected to fires that resulted in four deaths and 79 injuries, the department said.
The battery that caused a Nov. 5 fire was charging near the front door of an apartment, blocking its only exit and prompting firefighters to conduct a rope rescue of two occupants. And in August, a fire caused by a lithium-ion battery killed a mother and daughter in Harlem.
These fires can occur without warning and spread quickly, the chief fire marshal, Daniel E. Flynn, said at a Nov. 7 news conference.
“We have a fully formed fire within a matter of seconds,” he said.
The damage from a fire caused by lithium-ion batteries inside a Manhattan apartment this month. Credit. Fire Department of New York, via Agence France-Presse — Getty Images
Take these simple steps to reduce the risk of batteries failing.
One out of every 10 million lithium-ion batteries fails, a condition that almost always leads to a fire, Ms. Hutchison said. While that is a relatively low rate, the batteries are being used in more devices, including cheaper, uncertified batteries with greater risk, she said. Customers should always buy batteries and devices that have been certified by UL or another safety testing lab.
Fires have also been started because people have used chargers incompatible with a battery, she said. They should only use the charging cables recommended by a manufacturer, she said. An incompatible one might continue to charge the battery to the point of overheating.
“Once it reaches its thermal threshold, it’s a pretty violent reaction,” Ms. Hutchison said.
Lithium-ion batteries show signs that they need to be replaced if they get hot, expand or take longer than usual to charge, Ms. Hutchison said. Immediately before failure, a battery will make a popping noise and then a hiss in which gas is released. Experts recommend storing them in fireproof containers.
Even a battery that complies with safety guidelines when it’s first purchased can become dangerous if it’s damaged, said William S. Lerner, a hydrogen expert and delegate for ISO, an organization for global standardization.
“These batteries can be of the highest quality, but if they are injured and dropped and severely beaten up, then the potential to fail is greater,” he said.
Food couriers rely on e-bikes in New York City. The bikes grew in popularity during the pandemic as people sought alternatives to public transportation and ride-sharing services. Credit. Jutharat Pinyodoonyachet for The New York Times
It’s a widespread problem but not well-regulated.
No large-scale database keeps track of battery-caused fires, Mr. Lerner said. But the fires have occurred around the world.
The popularity of e-bikes in New York City grew during the pandemic as people looked for alternatives to public transportation and ride-sharing services, Mr. Lerner said. But their use increased before the government could put guidelines in place.
The New York City Housing Authority had proposed a ban on storing e-bikes in buildings but faced pushback from people like food couriers whose jobs depend on them. The authority said it is still working on steps for a proposed new rule.
The issue remains top of mind for housing managers. A sign outside the Manhattan apartment complex where the fire this month occurred read, “No pedal or e-bikes allowed beyond this point.”
The City Council is considering several battery safety measures and held a hearing Monday night. Laws that would ban sales of noncertified batteries and require educating people about the risks of powered mobility devices are among the measures being considered.
Leny Feliu, a founder of Safer Charging, said her brother is a delivery person. “He makes his money that way and I want him to continue to make his money, but we need to provide a safe way of charging these items,” she said.
The property management companies Douglas Elliman and AKAM, which oversee about 700 apartment complexes in New York City, have begun to communicate with residents and managers about lithium-ion battery safety.
“We want to be proactive, not reactive,” said Chris Alker, the vice president of operations for AKAM. “We don’t want to wait for a fire in order to address situations like these.”
What’s causing all the ebike and escooter battery fires?
Cate Lawrence is an Australian tech journo living in Berlin. She focuses on all things mobility: ebikes, autonomous vehicles, VTOL, Smart ci (show all) Cate Lawrence is an Australian tech journo living in Berlin. She focuses on all things mobility: ebikes, autonomous vehicles, VTOL, Smart cities, and the future of alternative energy sources like electric batteries, solar, and hydrogen.
The City of New York is grappling with a problem — fire. Specifically, escooter and ebike lithium-ion batteries catch fire and sometimes explode. And there’s no sign of it ending anytime soon.
Earlier this year, I wrote an introductory article detailing the rate of lithium-ion battery fires. Today I want to look at New York as a cautionary tale in the struggle of dealing with battery fires as ebikes (and, to a lesser extent, escooters) become mainstream.
I’ll follow up with a third article shortly exploring potential technological solutions to prevent battery fires.
What causes battery fires?
In the case of ebikes and escooter fires, there are numerous causes. Firstly, when we talk about a lithium-ion ebike or escooter battery, we’re talking about a bunch of connected batteries stored in a plastic case. A huge amount of energy resides in this small space.
Any one of the batteries is susceptible to overheating, which can be caused by;
- poor design
- assembly errors
- electrical shorting
- use of the wrong charger
- overcharging
- A damaged battery management system (BMS) causes overheating and inadequate cooling
- damage to the case.
Once a battery overheats, it can lead to a thermal reaction inside a battery. This is known as a thermal runway event. The reaction produces enough heat to cause adjacent battery cells to also catch fire or explode.
These fires happen incredibly quickly, and due to the self-sustaining process of thermal runaway, Lithium battery fires are also difficult to extinguish. They can leak toxic chemicals dangerous to people and pets.
Large batteries such as those used in Electric Vehicles can reignite hours or even days after the event, even after being extinguished. Fortunately, this is far less common in ebikes and escooters.
The problem in New York
To date this year. 130 reported fires involving lithium-ion batteries in electric bikes and scooters in New York have been reported. Five people died. Comparatively, this time last year saw only 65 ebike and escooter battery fires.
It’s worth stressing that these fires make up only a small percentage of all blazes in New York. It’s also highly likely that the growth in ebikes and escooters residing in the city is responsible for the increase.
But the fires are still a cause for concern, resulting in property damage, injuries, and less frequently, death. The ferociousness of a lithium-ion battery fires means multiple trucks are called, diverting attention away from other emergency services.
Further, the fires are indicative of a bigger issue facing the city.
New York has over 65,000 delivery workers, many of whom use ebikes. Gig economy workers take their ebike to limits beyond a daily commute, with all the risks outsourced to the riders.
Ebikes are ridden for hours at a pop and in extreme weather conditions such as high heat, rain, hurricanes. and snow, all of which can degrade a battery casing, increasing the likelihood of battery damage.
For many riders, the only place they charge is at home in their cheap apartment. The problem compounds when delivery workers share apartments, store their ebikes inside, and all charge their batteries overnight. And in a long shift, a rider may need more than one battery.
Earlier this year, journalist Wilfred Chan visited an ebike shop in New York equipped with powerboards charging multiple batteries for delivery riders. Staff offered her a charging spot for 50 a month.
Amazingly, there have been no fires there to date.
Is cost-efficiency to blame?
Except for some rental schemes I’ll share with you tomorrow, most riders have to pay for their own bikes, batteries, and chargers, making cheap or second-hand ebikes. and batteries appealing.
Reputable brands undergo extensive performance and safety testing to comply with UL solutions UL 2849, the Standard for Electrical Systems for eBikes. However, black market or cheap purchases may not include a certified Battery Management System that stops charging when a battery is full or overheating.
According to David TenHouten, VP, of vehicle engineering at micromobility company Bird, there’s also an issue of how far an operator pushes the boundaries within the safe cell parameters.
Vendors can push things right to the edge, or you can be a little conservative. Basically, if you’re more aggressive, you can get more performance out of the cells and push them farther and get a little farther range, but you’re getting into the risk boundaries at the edges.
The problem compounds with age as “these batteries are not getting any younger. They’re actually just getting a lot older very quickly.”
Charlie Welch, CEO of Zapbatt. stresses that the problem is that manufacturers set specs for their cells that you’re supposed to follow pretty strictly.

Often with ebikes and escooters, everyone rides them like they stole them. It puts the cell in a worst-case scenario every day, like somebody jumps on it, guns at full power, then later puts it in a warehouse, fully charged, and lets it sit there all night. Which from a cell perspective is where it doesn’t want to be.
Worse, riders may incorrectly convert a regular bike to an ebike or follow a YouTube tutorial to increase battery power or speed.
Unfortunately, cheap ebikes and repurposed bikes and chargers aren’t the only culprits.
In 2015, Pedego recalled every model they ever sold due to battery fire potential.
Specialized Bicycle Components has recalled electric mountain bike battery packs several times due to fire hazards.
Santa Cruz Bicycles issued a recall notice for Heckler 9 electric bikes sold between January and March 2022.
I spoke to Jim “Jimmy Mac” McIlvain, a writer, editor, and bike expert tracking ebike fires. He notes that:
“Established companies like Specialized, Santa Cruz, and Pedego stand behind their products. But the number of e-bike companies selling to US consumers is well over 181 brands ! Brands you probably have never heard of.
If one of those brands ignites a catastrophic home or forest fire, they will simply vanish, leaving no recourse for the consumer or municipality.”

To date, there is no evidence that fire brigades are tracking the make of ebike batteries or charges that catch fire.
According to McIlvain, neither he nor his wife would charge their ebikes inside their home, noting, “And if a battery were to be dropped or damaged, we would never use it again.”
So what is New York City doing about the problem?
Inner-city residents reap the benefits of the convenience of gig economy riders. Yet the city has made no effort to provide infrastructure like charging stations and secure places for storage.
Instead, a lot of talk fails to get to the heart of the problem and acknowledge that micromobility as a movement is expanding rapidly with no sign of abating.
The New York Housing Authority recently announced a proposed change to government housing regulations that residents and their guests may not keep or charge ebikes or ebike batteries in apartments or common areas. This has the potential for illicit underground storage schemes (yes, with batteries all charging overnight) — this makes my head spin.
New York’s Metropolitan Transport Authority (MTC) is considering a ban on ebikes and escooters. This is despite the fact there have to date been no relating fires in the transport network.
Interestingly, New York Councilwoman Gale Brewer proposes legislation to ban second-use or refurbished batteries.
This won’t do much to stop the fires caused by new store-bought ebikes. She also suggests that delivery posters and delivery apps should make riders aware of potential battery risks. She also sees a need for fireproof storage areas with charging ports (not sure who will pay for that).
Brewer’s most interesting idea is to call Congress to convene a hearing to push for federal legislation to hold battery manufacturers accountable.
McIlvain believes that it is inevitable that the government will need to step in, noting that “the toaster in my kitchen, the nightlight in the hallway, and all the power tools in the garage need to meet a federally recognized safety standard, so why don’t ebikes?”
What’s clear is that micromoblity is rapidly gaining momentum, and this is a complex problem that requires a complex solution encompassing manufacturers, riders, delivery services, and city officials.
Get the most important tech news in your inbox each week.