A battery that becomes hot enough to deform its holder is not behaving like an ordinary warm cell. Heat alone does not identify the cause, but a short, incorrect installation, reverse charging or a damaged cell or device can create a hazard.
What should I do with a hot AA battery?
Stop using the device. Do not continue operating it with a hot, leaking or deformed cell, and do not recharge primary alkaline or zinc-carbon batteries. Keep hands away from a hot or leaking battery; follow the battery maker’s handling and disposal directions after it has cooled. If the cell smokes, vents or catches fire, leave the area and contact emergency services.
Can batteries get warm during use?
Some batteries may become slightly warm under load, but a hot cell, leakage or a melted holder needs investigation. Check the device and battery instructions and replace damaged components. Do not mix old and new cells or different battery types in one device.
