Why a battery swells, and why that’s dangerous
A swollen battery is one of those problems you shouldn’t put off. Here’s what happens inside a battery, why it swells and what to do if you notice it.

1. Inside: thin layers and a liquid
A lithium-ion battery has thin layers of positive and negative electrodes with a separator between them, all soaked in a liquid called the electrolyte.
2. Heat and wear produce gas
Heat, wear and overcharging break the electrolyte down, and gas forms as a result.
3. The gas has nowhere to go, so the battery swells
The battery’s casing is sealed, so the gas builds up inside and puffs it up like a pillow.
4. This is what it looks like in real life
These are swollen batteries we removed from customers’ devices. A battery like this can push the screen out or lift the back cover.


5. Puncture it or keep charging it, and there’s a fire risk
If you puncture a swollen battery or keep charging it, it can catch fire.

Common causes
Age and wear, overheating (for example in the sun or under a pillow), cheap, low-quality chargers, knocks and drops, and a battery that’s always kept at 100% or often drained to zero.
6. What to do if your battery is swollen
Don’t press on it and don’t charge the device. Bring the device to us: we’ll remove the swollen battery and fit a new one.

Tips
- Don’t leave your phone charging on a bed or under a pillow: it can overheat there.
- Use good-quality chargers and cables.
- Send us your device model and we’ll tell you what to do. Call +371 22 142 142 or message us on WhatsApp:
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