Thermal Runaway
Definition
Self-accelerating exothermic reaction in a lithium-ion cell where internal heat generation exceeds heat dissipation, leading to rapid temperature rise, gas generation, and potential fire.
Why It Matters
- Most severe failure mode for lithium-ion batteries
- Can propagate cell-to-cell if not contained
- Triggered by internal short, overcharge, crush, or external heat
- Prevention requires proper BMS, thermal management, and mechanical design
Common Pitfalls
- Inadequate cell-to-cell thermal barriers
- Not designing for thermal runaway propagation prevention
- Inadequate venting for gas release
- Not testing thermal runaway scenarios in validation