Lithium-Ion Thermal Runaway
Definition
A self-reinforcing exothermic reaction within a lithium-ion cell, triggered by mechanical damage, overcharge, or elevated temperature, that propagates from cell to cell within a battery pack and can reach temperatures of 400 to 900°C, igniting adjacent materials.
- Triggers
- Mechanical damage, overcharge, elevated temperature
- Behavior
- Self-reinforcing exothermic reaction
- Temperature range
- 400 to 900 C
- Spread pattern
- Propagates cell to cell within a battery pack
Common questions
Why does thermal runaway spread from one cell to neighboring cells?+
The heat and gases released by one failing cell raise the temperature of adjacent cells past their own failure threshold, so a single cell fault can cascade through the entire pack without adequate separation or cooling.
What does thermal runaway typically look like at a fire scene?+
Investigators often look for a battery pack showing swelling, venting patterns and cell by cell deformation, distinguishing it from a simple electrical short elsewhere in a device.
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