This is one of the insidious issues that mobile devices face, and hope nobody has to face this. One of the primary causes of a swollen battery is overcharging. Mobile devices have circuits designed to prevent overcharging. Swollen by overcharging takes place when such circuits fail for some reason.
Things like NON-OEM (none original equipment manufacturer) chargers, batteries, and particularly if they are not designed to handle the right voltage and wattage leads to risks like overheating, swelling battery, etc. Other times it was just the battery so bad. One word of CAUTION, never ever even try to repair a battery in any way and under any circumstances. This can expose you to the risk of getting burned.
Prevent damage of your battery
So what are the solutions? The best solution is the obvious one, prevention is better than the cure. No matter what, don’t let the battery overheats while charging, and while using. Always look for OEM batteries and chargers. Refer to your manufacturer’s manual or documentation for instructions to avoid such a disaster.
Also, one other thing is that prevention may not always prevent. A swollen or bad battery may rupture, leak, and catch fire. The important thing here is to beware that things can go wrong regardless of your precautionary measures. Be vigilant for any kind of recurring signs, and be incredibly careful and considerate when dumping a swollen battery.
Clues like changes in the device’s screen and frames, how they come together, the way it sits on a flat surface, the back cover stays on the back, any creaking or popping, unusual heat, etc. These are the clues you want to be vigilant about. If your device allows you to remove its back cover, remove the cover and inspect the battery. If the device does not allow you to open the back cover, you may want to take it to a technician who has expertise in mobile devices or take it to an authorized service centre.
If you come across a swollen battery, dispose of it according to the e-waste rules and regulations of your place. Never just dump them with random trash. This can cause harm or the person picking up the trash. Replace the swollen battery with a new, fresh one if the device has a replaceable battery. Prefer vendor-specific OEM batteries over third parties.