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I have a swollen lithium-ion battery what should i do?


A swollen battery might seem like a minor problem, but it can be quite dangerous.

Lithium-ion batteries have increased in popularity in recent years, commonly found in mobile phones, power tools, laptops, tablets, e-cigarettes, e-scooters and e-bikes, they have become standard in the electronics industry. The batteries are widely used because they are light-weight, contain a lot of energy for their size, have long cycle durations and shelf-life, are quick to recharge, and have low self-discharge rates.

Lithium-ion batteries, however, do not like high temperatures and if used incorrectly have the potential to enter a thermal runaway cycle when under stress and catch fire and explode. Fortunately, the devices that utilise lithium-ion batteries must contain a battery management system (BMS) that shuts the battery down when these cycles are detected.


Swollen batteries, while not common, are a significant risk. They are the result of too much current inside a cell of the battery, which causes a build-up of heat and gas. This can be caused by several factors, however, the most common are overcharging, manufacturing defects, deep discharge, or damage to the battery.


Manufacturer defect is something you cannot avoid, however there are a range of things you can do to minimise problems and prolong your battery’s life.

Do not leave your device continuously on charge after the charge cycle is complete, lithium-ion batteries are meant to cycle – discharge and recharge – so keeping them plugged in all the time means that they cannot exercise to their capacity.

Always use the charger supplied with the device or recommended by the manufacturer. Going for an alternative cheaper option might seem like a good idea, however the charger may not have the same power output and could damage your battery or device.

Avoid storing, using, or charging batteries at very high or low temperatures.

Protect batteries against being damaged especially from being crushed, punctured, or immersed in water.

Replace the battery if it is damaged or no longer performing as it should.

Store the device in a cool, dry environment. Hot cars and humid environments are not good for battery health.


Do not ever try to puncture the bulge in your lithium-ion battery. Swelling of lithium-ion batteries is caused due to heat and build-up of gases, which make the battery vulnerable. Puncturing a swollen lithium-ion battery may lead to fire and explosion.

Even if your device still works, if the battery is swollen, the battery must be replaced immediately, using the device or leaving it connected to power can be dangerous.

Carefully remove the battery and place the battery directly into a lithium-ion fire & smoke containment bag if you have one. If you do not have a containment bag then place the battery in a container in a dry cool place, away from other batteries and combustibles, ideally outside to await disposal.

On all occasions a swollen battery is discovered please raise an Incident

If at anytime the swollen battery starts to smoke, do not touch the battery, sound the fire alarm, dial 999 and ask for the Fire Service providing the details, follow the fire procedure and inform Security of your actions.


If the swollen battery is not smoking and is stored safely you should contact the Sustainability Department for disposal advice, the cost of disposing of these batteries will be re-chargeable to the department.

Never place lithium-ion batteries in the general waste bins or with other recyclable materials like card and plastics.

For further information on lithium-ion battery safety or advice on how to obtain a Lithium-ion Fire & Smoke Containment Bag, please contact the university Fire Safety Advisor, Tel: - 0118 378 8282, Email: -

Lithium-ion battery fire & smoke containment bag instructions