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Battery swelling and what to do about it

5 July, 2023

Battery swelling and what to do about it

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Battery swelling is common and can be met in batteries of various appliances.

Swollen laptop batteries, phone batteries, UPS, power bank or media player and gaming console batteries, they can all bloat, become puffy and inflated, and potentially cause a lot of trouble. Here’s what you need to know.

Why do batteries swell?

Batteries can swell or expand for several reasons. First of all, age and wear. As batteries age, their internal components can deteriorate. This degradation can result in the production of gas inside the casing of the battery. This production of gas is what is causing the swelling, which we usually refer to as gassing or outgassing.

Battery swelling - Swollen laptop battery

Swollen laptop battery

Then there is the case of manufacturing defects that may compromise a battery’s integrity. These defects can cause gas buildup or lead to the formation of internal shorts, again resulting in swelling.

Another very common cause is overcharging. When a battery is subjected to continuous overcharging, it can cause the electrolyte inside the battery to break down and generate gas. The accumulation of gas leads to an increase in pressure, causing the battery to swell. Here’s an interesting video showing different batteries being overcharged, and what the results are:

High temperatures can accelerate the chemical reactions within a battery, causing excessive gas production. These high temperatures can be a result of a short circuit or overheating due to overcharging.

How much swelling is normal in a battery?

The answer is quite simple: none. A battery should not be swollen, bloated, puffy, inflated, or in any way deformed compared to how it was when it came out of the factory. If you have such a battery, you should act! Continue reading for more details on what to do.

Battery swelling - Bloated battery from a UPS

Bloated battery from a UPS

How can I tell if my battery is swollen?

The obvious was is to do a visual check, but in some cases, swelling may not be very apparent or easy to see. If your battery is removable, the best way is to remove the battery from your device and place it on a straight and smooth surface such as a table or bench. The battery should not be wobbling at all; it should stand firmly where you put it. If you see any movement at all, then there’s a good chance that your battery has started swelling.

If for any reason you cannot remove the battery from the device, you can also look at the device itself. Often swollen or bulged batteries will create deformities on the device they are powering. Here are some examples of what to look for:

Battery swelling - Swollen laptop battery in a Chromebook

Swollen laptop battery in a Chromebook

Battery swelling - Swollen power bank

Swollen power bank

Battery swelling - Swollen phone batteries

Swollen phone batteries

Are swollen batteries dangerous?

Unless you bought your batteries from the cheapest and lowest quality supplier available online, swollen batteries are not incredibly dangerous. You do need to handle them with care, but (proper) manufacturers have introduced a lot of measures to prevent fires or other nasty surprises coming from swollen batteries, so you need not worry that it will spontaneously combust or explode.

The main thing to remember is that, once a battery is swollen, you need to handle it carefully.

I have a swollen battery! What do I do?

First of all, if you notice your battery swells during charging, you need to immediately remove the charger. Charging intensifies any issues and needs to stop immediately. This is why we always advise that you never leave a battery charging unattended.

It goes without saying that if you were not charging the battery when you noticed it’s swollen, do not charge it!

If you just have a swollen battery in a device, move it together with the device to a well ventilated area. You can wait until the battery discharges completely, which helps reduce the chances of a sudden reaction. You can remove the battery carefully without any tools. If you have to use tools, make sure they are blunt and made of plastic to avoid any punctures or shorts. A great idea is to use a special fire proof bag specifically designed for battery storage and disposal.

If you cannot remove the battery yourself, the best approach is to take the device to a specialist repair shop.

If you notice any smoke coming out of it, make sure you move it (along with the device if need be) to a well ventilated area and away from any flammable items or materials that may be laying around. This will ensure you won’t be breathing any of the chemicals the gas may release, and if there is a fire it will be contained and won’t spread. If the battery has already started leaking gas, make sure you wear protective equipment such as goggles and gloves designed to withstand heat if it starts burning. Do not use surgical gloves, as the heat will probably melt them on your skin. Of course, if there is no fire or gas leaking, then you don’t need any of that, you just move the battery outside.

My battery is puffed up. Should I puncture it to release the gas inside?

Absolutely not! Avoid any punctures and place the battery in a place that would prevent a puncture from happening, or use the bag mentioned above.

Battery swelling - Swollen phone battery

Swollen phone battery

Can a swollen battery be fixed?

We have read a few articles on the Internet saying you can repair a swollen battery. Never attempt to do that, this battery’s integrity has been compromised irreparably and will never be safe for reuse.

How do I dispose of a swollen battery?

Properly dispose of your battery by getting in touch with a certified battery recycling centre or contractor that specialises in battery disposal.  Do not throw the battery in your bin, as it imposes risks for those who will unknowingly be handing it, and is very bad for the environment.

Is there a way to prevent a battery from swelling?

There are some preventative measures you can use. First of all, make sure you use the right charger for your battery chemistry, or the battery certified and approved by the manufacturer of your device. Using high quality chargers from reputable manufacturers will ensure both the safety and longevity of your batteries and the devices they are powering. You can find more about chargers in our Battery Chargers section.

Also, avoid leaving a device on charge for too long. When the battery is fully charged, remove the charger.

Using genuine batteries may be a bit more expensive, but it will guarantee proper operation and no headaches. Plus, they will provide the capacity they claim, something that doesn’t happen with cheap aftermarket batteries.