The surge in micro-mobility in New York City has been accompanied by a concerning increase in incidents involving lithium-ion batteries powering these vehicles. In the past year alone, there were 216 battery-related fires in NYC, resulting in 147 injuries and six deaths. This represents a significant rise from the previous year, where there were 104 fires, 79 injuries, and four deaths.
FDNY Captain Michael Kozo has highlighted the gravity of the situation, stating that "Fires caused by lithium-ion batteries have increased dramatically in New York City with deadly consequences." Mayor Eric Adams has echoed this sentiment, pointing out that uncertified lithium-ion batteries are at the heart of this problem.
Despite the risks posed by these fires, there are no immediate plans to ban or restrict the use of electric modes of transportation, as they provide a crucial source of income for many New Yorkers. E-bikes and scooters are ubiquitous on the city's bustling streets, with over 60,000 app-based food delivery workers relying on them to make a living.
This trend shows no signs of slowing down, with the online grocery sector projected to grow at a rate of $740.88 billion from 2022 to 2027. However, there is a pressing need for improved safety measures and stricter regulations to mitigate the risks associated with lithium-ion batteries in micro-mobility devices.
NYC safety measures
In NYC, safety measures have been prioritized through a series of bills passed in July 2021 to expand the use of electric bicycles and scooters. These bills included regulations for e-bike and e-scooter use, such as speed limits and helmet requirements, and established a new permit system for shared e-scooter companies.
To further prioritize safety, Mayor Eric Adams announced the NYC Streets Plan, which allocates $904 million towards the construction of 250 miles of protected bike lanes by the end of 2026. Additionally, the Mayor has committed to reinforcing 20 miles of these bike lanes with concrete barriers.
Further, the mayor has signed several bills into law that mandate the certification of electric mobility devices rented, sold, or leased within the city, and has released the Micro-mobility Action Plan to further promote safe and sustainable transportation options in NYC.
What’s causing the battery fires?
Identifying the root cause of micro-mobility fires requires tracking the events themselves. In 2019, only 13 e-bike fires were reported in NYC, but there has been a significant increase in reported fires since then. Several factors can contribute to these fires, including the lack of certification, battery chemistry, lack of maintenance, swapping batteries, and overcharging.
The high cost of quality e-bikes often leads to the adoption of unsafe or unproven technologies by micro-mobility users. At a minimum, battery cells should have UL 1642, IEC 62133-2, and DOT/UN 38.3 certification marks, while battery packs should have UL 2271, IEC 607300-1, and EN 50604-1 certifications. However, even with these certifications, real-world environmental conditions can cause battery fires.
Standard lithium-ion batteries are widely used to power e-scooters and e-bikes, but they suffer from two major safety issues - lithium deposition and thermal runaway. Lithium deposition occurs due to everyday use, resulting in "whiskers" forming inside the battery, which can lead to spontaneous fires. Thermal runaway is a chain reaction inside battery cells that creates a self-sustaining fire that can grow. These fires can also occur spontaneously due to carbon within the batteries fueling the fire.
As batteries age and degrade due to regular use on the busy streets of NYC, the lack of maintenance can increase the risk of battery fires. Procuring batteries without considering their usable cycle life or "lifetime" can also contribute to this problem.
Delivery workers who work long hours may purchase multiple batteries and swap them to avoid downtime and revenue loss, but this practice can be dangerous. Battery swapping can cause short-circuiting and physical battery damage, and if the swapped battery's voltage, capacity, or chemistry doesn't match the bike's requirements, it can damage the battery and the bike's electrical system and cause a fire.
Last, overcharging batteries overnight and indoors can cause a breakdown of the core chemistry and a buildup of heat and pressure within a lithium-ion battery, leading to swelling, leakage, and explosion. Therefore, overcharging batteries is like filling a barrel of gas sitting over a pile of wood; if you overfill the tank and create a spark, you have a fire that you can't put out.
No waiting for a miracle battery
There is a redefined battery chemistry on the horizon that offers advantages over traditional lithium-ion batteries. Lithium-titanate (LTO) batteries have been used in industrial and military applications for a long time, and they are carbon-free, fire-resistant, and capable of withstanding extreme temperatures. Unlike lithium-ion batteries, LTO batteries with the proper BATV integration are immune to lithium deposition and dendrites, making them more durable and longer-lasting. LTO batteries can also self-heal, which prevents thermal events under extreme conditions.
Using LTO batteries in micro-mobility has several benefits, including quick charging, durability, fire resistance, AI compatibility, thermal adaptivity and replaceability. LTO batteries can be charged 10 times faster than standard lithium-ion batteries without degrading their lifetime, making them ideal for users who need to quickly charge between rides, especially in densely populated areas like NYC. LTO batteries can be charged and discharged up to 15,000 cycles, giving them a twenty-plus year lifespan, and they can withstand physical damage without sparking a fire.
LTO batteries are also fire-resistant, making them safer for indoor charging in densely populated areas. They are AI-friendly and allow for more freedom to optimize energy usage. LTO batteries can adapt to a variety of vehicles and voltages, making them easy to swap with any lithium-ion battery without changing hardware in the operated device. Finally, LTO batteries have been tested and proven by the Department of Defense, making them a reliable and safe option for micro-mobility.
LTO for a better ride
The increasing popularity of micro-mobility in New York City offers the world valuable insights on both beneficial practices and mistakes to avoid. By demonstrating effective management and proactive approaches to handle the growth of this sector, the city underscores the importance of preparedness and prevention of potential hazards, such as fires.
As the demand for micro-mobility continues to surge, it is crucial to prioritize safety, and LTO is poised to provide a safer battery option for riders to help them ride with confidence and peace of mind.
Charlie Welch is the CEO and Co-founder of ZapBatt, a battery provider for various markets, including mobility, small infrastructure, and consumer products and innovator behind LTO batteries for micro-mobility.
Amiad Zionpur is the COO of ZapBatt and has been involved in the micro-mobility space for many years.