By Emilee T. Austin, Wesley R. Attwood and Stephen J. Ringer
Lithium-ion battery-powered devices are becoming increasingly common in residential homes, supported by higher power density, increased storage capacity, and decreasing costs due to mass production [1]. These devices include cell phones, laptops, toothbrushes, power tools, electric vehicles, scooters, and bikes.
Despite many advantages, one safety drawback is the possibility that these batteries can overheat, catch fire, and in extreme cases, cause explosions. Fires involving various lithium-ion battery-powered products have been increasing at an alarming rate and have resulted in numerous injuries and fatalities. 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 [2]. Specifically, testing has demonstrated that lithium-ion batteries can contribute to faster fire propagation, shorter time to flashover, rapid changes in fire dynamics, shorter escape times, shorter time to collapse, and other unknown hazards [3].
Lithium-ion batteries can experience 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 and mechanical stress from dropping or crushing [2]. Thermal runaway can occur minutes, hours, or days after the battery is damaged [2].
A recent fatality investigation report published by National Institute for Occupational Safety and Health’s Fire Fighter Fatality Investigation and Prevention Program (FFFIPP) identified how improper charging of lithium-ion battery-powered devices can result in thermal runaway and rapid fire [4]. The investigation identified considerations for firefighters to reduce the probability and severity of lithium-ion battery fire and explosion risks.
FFFIPP 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 source in an attached garage that had extended into the house. Upon investigation, the fire was believed to have been started by a lithium-ion battery-powered electric scooter, located in the garage. The scooter battery went into thermal runaway after being charged with an aftermarket charger. The heaviest concentration of heat and fire damage appeared to be in the interior of the garage in the general location of the electric scooter and lithium-ion battery [4].
Overhaul Inventory Card
Based on the details of this investigation, NIOSH and UL’s Fire Safety Research Institute developed an Overhaul Inventory Card with instruction (see images below). This card can serve as a tool to remind firefighters to 1) check for lithium-ion battery-powered devices present in a residential structure during overhaul; 2) check the devices for exposure to fire; and 3) take appropriate actions, including removal. Since these devices can experience thermal runaway long after being damaged, it is important to identify potential fire exposure to prevent additional fires in the structure after the incident ends and the fire department leaves the scene [5].
Incident commanders, with input from homeowners/occupants, may use this card to identify the locations of lithium-ion battery-powered devices in the residence [5]. Upon completing the inventory card, the IC, in collaboration with the responding operations or assigned firefighter can work together to 1) locate the devices and check for fire exposure, and 2) isolate, remove, or appropriately extinguish identified devices.
Full structural PPE with an SCBA can help protect firefighters during overhaul when lithium-ion battery-powered devices may be present. Also, the addition of lithium-ion batteries to the fuel loads in structure fires increases the importance of performing gross decon at the scene with soap, water, and a brush [6].
Final thoughts
As lithium-ion batteries have become more common, so have related fire incidents. The fire service has been diligent in developing and implementing appropriate safety protocols and training to mitigate these risks. Use of the Overhaul Inventory Card serves as one additional tool that may help limit the fire and explosion risks of lithium-ion batteries in the home and protect firefighters during a structural fire response. Download a copy of the card.
Disclaimer: The findings and conclusions in this report are those of the author(s) and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention.
REFERENCES
- Diouf B and Pode R [2015]. Potential of lithium-ion batteries in renewable energy. Renewable Energy 76:375–380.
- 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.
- 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.
- 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.
- NIOSH and Fire Safety Research Institute [2025]. Overhaul Inventory: Lithium-ion Battery-Powered Devices. By Attwood WR, Loflin ME, Niemeier-Walsh M, Page F, Ringer SJ, Tarley J, and Madrzykowski D. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health.
- NVFC [2021]. Lavender ribbon report: Best practices for preventing firefighter cancer. Washington, DC: National Volunteer Fire council.
ABOUT THE AUTHORS
Emilee T. Austin, MA, is a Health Communication Specialist with the Fire Fighter Fatality and Injury Prevention Program (FFFIPP) within the NIOSH Division of Safety Research.
Wesley R. Attwood, DrCJ, is an Investigator and Program Advisor in the NIOSH Fire Fighter Fatality Investigation and Prevention Program within the Division of Safety Research and is a Coordinator for the NIOSH Public Safety Program.
Stephen J. Ringer, CFEI, is an Investigator with the NIOSH Fire Fighter Fatality Investigation and Prevention Program within the NIOSH Division of Safety Research.
