FDNY officials are warning that the lithium ion batteries from increasingly-popular e-bikes present a fire hazard, and have already been responsible for at least 140 fires in the last 16 months alone. Those fires have caused dozens of injuries and at least 5 deaths in New York City since the start of 2021.

According to WCBS-TV, FDNY put out four fires attributed to the bikes in a single day on Thursday. One of those fires consumed two houses on East Ninth Street in Brooklyn. According to the Daily News, the fire took 100 firefighters over two hours to put out, and caused 7 injuries. The Fire Department said that these fires were nothing new, and that there have already been over 40 fires this year started by e-bikes, at least one of which has been deadly. Officials further said that there were over 100 such fires in 2021, leading to 79 injuries and at least four deaths.

A dozen people were noted to be injured in Thursday's e-bike fires alone.

Lithium-ion battery-powered conveyances have become increasingly common in many large cities, but they do come with risk. FDNY suggests that the lithium ion batteries that come factory installed with these devices are generally safe, but the problem seems to occur when customers cut corners by purchasing third-party replacement batteries that may not always be appropriately tested or safe.

FDNY additionally warns that sometimes replacement charging cords manufactured by third parties can malfunction and cause fires. The rash of fires caused by these devices and their charging cables led FDNY to release a safety video with tips on how to avoid your device exploding or catching fire.

In spite of the rash of fires, city officials have recently encouraged the city to purchase even more e-bikes for use in the Department of Transportation fleet. During his recent campaign, Mayor Eric Adams promised to subsidize e-bike purchases for NYC residents.