FITCHBURG — On the morning of Saturday, June 7, 2025, firefighters responded to 44 Ronald Street on the city’s west side after a lithium-ion battery overheated and ignited in the basement, according to Fitchburg Fire Chief Dante W. Suarez.
Crews encountered heavy smoke upon arrival and quickly identified the source as a lithium-ion battery that had entered “thermal runaway”—a chain reaction in which an overheating battery cell releases heat and gas, causing neighboring cells to fail and potentially ignite. This process can lead to explosions/sudden fires and is difficult to stop once initiated.
Fitchburg Engines 1, 2, and 4, Ladder 3, and Rescue 3 responded, along with mutual aid from Leominster Ladder 1.
Firefighters brought the blaze under control within about an hour.
No one was injured, and residents were not displaced.
The Fitchburg Fire Department is urging residents to review lithium-ion battery safety guidelines from the Massachusetts State Fire Marshal.
