Hyundai i30 Sedan Hybrid Emergency Response Manual page 19

6. In case of fire.
6.4 High-voltage battery re-ignition by stranded energy
Damaged cells in the high-voltage battery can experience thermal runaway* and reignition.
To prevent reignition, the first responder and second responder need to be aware of the risk of stranded energy* which
remains in the damaged cells and lead to reignition.
* Thermal runaway: The originating cause of thermal runaway is generally short-circuiting inside a battery cell and a resulting
increase in the cell's internal temperature. Battery produces heat with thermal runaway and it can spread from one battery
cell to many cells, in a domino effect.
* Stranded energy: Energy remains inside any undamaged battery cells after the accident. That stranded energy can cause a
high-voltage battery to reignite multiple times after firefighters a fire.
How to prevent reignition (Mitigating stranded energy risk)
Use a thermal imaging camera to ensure the high-voltage battery is completely cooled before leaving the incident. Always
advise second responders that there is a risk of the battery re-igniting.
1. 12V battery terminal disconnection (to depower battery management system)
2. High-voltage shut off (refer to pages 7-9)
3. Discharging the high-voltage battery (refer to pages 22-23)
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