October 31, 2025
Gaining a greater understanding of battery safety and fire prevention can help protect people and property. Rechargeable lithium-ion batteries are found throughout many modern homes. These batteries are used in millions of devices, including phones, laptop computers, tools and electric bikes.
Rechargeable batteries can enter a state known as thermal runaway. This is a phenomenon in which a battery enters an uncontrollable, self-heating state that can lead to extremely high temperatures, smoke, fire, toxic off-gassing or an explosion.
Fortunately, education and greater awareness can help consumers prevent potential fires caused by thermal runaway. The Fire Department of the City of New York reported a reduction in deaths related to lithium-ion battery fires: from 18 in 2023 to six in 2024.
Devices with rechargeable batteries are often scattered throughout a home, which means the threat of a potential fire could come from many sources.
A recent news story about a resident in Massachusetts who sustained a minor burn from a lithium-ion explosion demonstrates the dangers of either faulty or improperly charged lithium-ion batteries. That episode also highlights the importance of researching and purchasing high-quality, certified batteries and using best practices for storage and charging.
Here are some key safety tips:
- Choose batteries certified to UL Standards, and look for the UL Mark
- Use only the charger provided by the manufacturer or specifically designed for the device
- Watch the device for heat, smoke or bulging
- Lithium-ion battery fires can emit toxic gasses, so if a fire starts, call 911
As highlighted in a previous UL Solutions news story on battery safety, thermal runaway is a critical issue for airline crew members and travelers. Because many rechargeable devices are easy to carry, airlines have added policies for safely traveling with lithium-ion batteries. Southwest Airlines has introduced a policy requiring passengers to keep power banks and portable charging devices in a visible place.
Raising awareness and minimizing the risk of mishaps from thermal runaway events at home and while traveling can help reduce injuries. For consumers, a small amount of research could prevent a major incident. To find certification information on batteries and other products, visit UL Product iQ®.
UL Solutions tracks lithium-ion battery incidents to drive understanding of this technology and where the greatest risks exist. To learn more, visit the Battery Safety Testing and Certification webpage.