By Wesley R. Attwood, Rebecca Knuth and Micah Niemeier-Walsh
Lithium-ion battery-powered devices are becoming more common in residential homes, supported by higher power density, increased storage capacity and lower costs due to mass production [1][2]. These devices include cell phones, laptops, toothbrushes, power tools as well as electric cars, scooters and bikes.
While lithium-ion battery-powered devices have advantages, there are safety considerations. The batteries can overheat, catch fire, release toxic vapors and, in extreme cases, explode. Fires involving lithium-ion battery-powered products have been increasing at an alarming rate and resulted in numerous injuries and deaths [2][3].
| MORE: Overhaul inventory: Lithium-ion battery-powered devices
A recent fatality investigation report published by the National Institute for Occupational Safety and Health’s Fire Fighter Fatality Investigation and Prevention Program identified how improper charging of lithium-ion battery-powered devices can result in thermal runaway and rapid fire development [4]. The report lists considerations for firefighters to reduce the probability and severity of lithium-ion battery fire and explosion risks in the communities they serve through public fire and life safety education.[5]
Lithium-ion battery hazards
Lithium-ion batteries can experience a chemical process called thermal runaway when a battery cell enters a state of uncontrolled self-heating and becomes destabilized. Thermal runaway is a primary reason why these batteries catch fire and explode. Because of excessive heat created by the battery cells, chemical reactions release thermal energy that transfers (runs) to the other cells in the battery pack. This is commonly caused by overcharging, overheating and mechanical stress from dropping or crushing the battery. Thermal runaway can occur minutes, hours or days after the battery is damaged, and can reignite even after the fire has been extinguished [4].
Even when the initial cause of a fire is not a lithium-ion battery-powered device, the involvement of lithium-ion batteries can increase the intensity and magnitude of the fire [4]. Specifically, testing has demonstrated that lithium-ion batteries can contribute to the following[6]:
- Faster fire propagation
- Shorter time to flashover
- Rapid changes in fire dynamics
- Shorter escape times
- Shorter time to collapse
- Other unknown hazards
Investigation summary
On Dec. 4, 2021, a 38-year-old lieutenant died when the floor collapsed at a residential structure fire. Upon arrival, the incident commander found the fire spreading into the house from the attached garage. The investigation showed the fire was likely started by a lithium-ion battery-powered electric scooter located in the garage. The scooter battery likely went into thermal runaway after being charged with an aftermarket (i.e., third-party) charger. The heaviest concentration of heat and fire damage appeared to be in the garage interior, in the general location of the electric scooter and lithium-ion battery [5].
Prevention through public fire and life safety education
Fire and life safety education, including education around lithium-ion battery-powered devices, is a fundamental element of community risk reduction. It aims to change the behaviors and beliefs of community residents to reduce risks, injuries and fires [7]. Fire departments act on this effort by training firefighters and other personnel as fire and life safety educators (FLSEs). FLSEs coordinate and deliver educational programs that teach community members about a particular risk and how to prevent it [8][9].
Examples of these programs include educating community members on the importance of:
- Working smoke alarms to reduce deaths in structure fires (e.g., 43% of home fire deaths between 2018 and 2022 occurred in residences with no smoke alarms [10]).
- Using child safety seats to lessen deaths and injuries of children involved in vehicle crashes (e.g., an estimated 325 children, four and younger, were saved by the use of child restraints in 2017 [11]).
- Installing carbon monoxide detectors and properly using gas-powered appliances, as every year carbon monoxide poisoning results in 400 deaths, 14,000 hospitalizations and 100,000 emergency department visits [12].
User errors can cause lithium-ion batteries to go into thermal runaway (e.g., overcharging, mechanical stress from dropping or crushing). As described in the investigation, this can also be caused by users charging the battery with aftermarket charging cords that are not compatible with the device [4]. Aftermarket charging cords are often sold to consumers as a cost-savings effort. Agencies such as the Consumer Product Safety Commission have identified instances where the use of an aftermarket charger poses a fire risk because the charger output voltage and current do not match the rating of the lithium-ion battery-powered product [13]. Manufacturers’ instructions often state their products should only be used with the original equipment manufacturer charger to avoid these fire risks.
Numerous government agencies and organizations have developed outreach materials to educate community members on the fire dangers of lithium-ion batteries. These include handouts, social media graphics, and safety messages to support use of product instructions when using, storing or disposing of lithium-ion battery-powered devices. Fire departments and FLSEs can employ these materials in their communities to educate people on the risk and prevention related to batteries overheating, catching fire or exploding [14][15][16][17]:
- U.S. Fire Administration (USFA): Battery Fire Safety
- Fire Department of New York (FDNY): Safety Tips for Lithium-ion Batteries
- Fire Safety Research Institute (FSRI): Take Charge of Battery Safety
- National Fire Protection Association (NFPA): Lithium-ion Battery Safety
Specific to this incident, FDNY, FSRI and NFPA outreach materials are available that emphasize the need to only use the original equipment manufacturer charging cord and follow the manufacturer’s instructions [15][16][17]. This includes messaging about the fire risks associated with aftermarket charger use.
Conclusion
As lithium-ion batteries have become more common, so have lithium-ion battery-related fire incidents [2][3]. The fire service has been diligent in developing and implementing safety protocols and training to help mitigate health and safety risks associated with these incidents. Use of fire and life safety education serves as an additional tool that may help limit the fire and explosion risks of lithium-ion batteries in the home and the community. When community members are educated, they can employ safer practices that can reduce the occurrence of fires and the risk of firefighters being seriously injured or killed at these fires.
Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention.
References
[1] Diouf B and Pode R [2015]. Potential of lithium-ion batteries in renewable energy. Renewable Energy 76:375–380.
[2] Austin ET, Attwood WR, and Ringer SJ [2025]. Overhaul inventory: Lithium-ion battery-powered devices. FireRescue1, May 23.
[3] Gilbert S, Fang H, Butry D, Tam W, Donnelly M, and Fung J [2026], Understanding the risk of lithium-ion battery fires - multi-source data analysis, Technical Note (NIST TN). Gaithersburg, MD: National Institute of Standards and Technology.
[4] Barowy A [2023]. The science of fire and explosion hazards from lithium-ion batteries: An introduction to lithium-ion battery construction, thermal runaway and potential hazards. Columbia MD: UL Firefighter Safety Research Institute.
[5] NIOSH [2025]. Lieutenant dies due to a floor collapse in residential structure fire with unpermitted renovations – Illinois. By Loflin ME, Attwood WR, and Austin E. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2022-09.
[6] Schraiber A, Barowy A, Gaudet B, and Kimmerly V [2023]. Considerations for fire service response to residential battery energy storage system incidents. Washington, DC: International Association of Fire Fighters.
[7] IFSTA [2015]. Fire and life safety educator. 3rd ed. Stillwater, OK: International Fire Service Training Association.
[8] NFPA [2024]. NFPA 1030, Standard for professional qualifications for fire prevention program positions. Quincy, MA: National Fire Protection Association.
[9] NFPA [2026]. NFPA 1750, Standard for the organization and deployment of fire suppression operations, emergency medical services, special operations, and fire prevention activities. Quincy, MA: National Fire Protection Association.
[10] McGree T [2024]. Smoke alarms in US home fires. Quincy, MA: National Fire Protection Association.
[11] NHTSA [2019]. Lives saved in 2017 by restraint use and minimum-drinking-age laws. Washington, DC: U.S. Department of Transportation, National Highway Traffic Safety Administration.
[12] CDC [2026]. Carbon monoxide poisoning basics. Atlanta, GA: Centers for Disease Control and Prevention.
[13] CPSC [2025]. CPSC staff briefing package, Safety standard for lithium-ion batteries used in micromobility products and electrical systems of micromobility products containing such batteries. Washington, DC: Consumer Product Safety Commission.
[14] USFA [2024]. Battery fire safety. Emmittsburg, MD: U.S. Department of Homeland Security, U.S. Fire Administration.
[15] FDNY [2024]. Safety tips for lithium-ion batteries. New York, NY: Fire Department of New York Foundation.
[16] FSRI [2023]. Take charge of battery safety. Columbia, MD: Fire Safety Research Institute.
[17] NFPA [2022]. Lithium-ion battery safety, Quincy, MA: National Fire Protection Association.
ABOUT THE AUTHORS
Wesley R. Attwood, DrCJ, is the senior investigator in the NIOSH Fire Fighter Fatality Investigation and Prevention Program and coordinator for the NIOSH Public Safety Program.
Rebecca Knuth, MS, is a health communication specialist with the NIOSH Fire Fighter Fatality Investigation and Prevention Program.
Micah Niemeier-Walsh, PhD, is an industrial hygienist with the NIOSH National Firefighter Registry for Cancer.
