Sourced fact
A leaking, cracked, bulging or unusually hot 12 V battery is classified Red and ProfessionalOnly.
Maintenance · UK
Damaged, leaking or hot EV 12 V battery: stop
A leaking, cracked, bulging or unusually hot 12 V battery is Red and ProfessionalOnly. Stop driving and all checks, keep people clear and avoid contact with liquid or deposits. Arrange professional recovery or emergency help appropriate to the surroundings and any exposure or injury.
RAC: How to check your car battery's health
Reviewed
Key facts and evidence
For UK EV owners, as reviewed on 12 August 2026, visible leakage, cracking, bulging or unusual heat at a 12 V battery is a Red stop condition. The battery must not be handled, charged, jump-started, cleaned or carried; keep people clear and use professional recovery, with emergency help where the surroundings, exposure or injury require it.
RAC: How to check your car battery's health
Sourced fact
People should be kept clear and contact with liquid or deposits avoided.
Sourced fact
The response is professional recovery or emergency help according to the surroundings and any exposure or injury.
Recognise a cracked, bulging, leaking or unusually hot 12 V battery, keep clear and transfer the incident to recovery or emergency professionals.
Recognition, not treatment
The consumer decision is limited to recognising visible damage, keeping people clear and transferring the incident. This page provides no cleaning, neutralising, charging, disconnection or carrying method for the affected battery.
What to do next
Do not drive or continue checking a vehicle when its 12 V battery is leaking, cracked, bulging or unusually hot.
Immediate action: Keep people clear and contact professional recovery or emergency help from a safe location.
- Stop all checks for leakage, cracking, bulging, unusual heat, rapid venting, irritation or suspected electrolyte contact.
Do not infer from missing evidence
- Keep people clear and avoid contact with the battery, liquid and deposits.
- Do not charge, jump-start, clean, disconnect, carry or continue using the battery.
Professional hand-off
- Tell professional recovery about the exact vehicle, visible condition, heat and any suspected exposure before they attend.
- Use emergency help when injury, exposure or the immediate surroundings make the incident urgent.
Questions this record can answer
What does the sourced evidence say about recognition, not treatment?
The consumer decision is limited to recognising visible damage, keeping people clear and transferring the incident. This page provides no cleaning, neutralising, charging, disconnection or carrying method for the affected battery.