What to do When Li-ion Phone Batteries Get Swollen Up

Earlier today, I noticed something strange on my phone’s screen – a permanent impression in the center of the screen as if someone is pressing the screen with a finger. At first I thought that it had something to do with the screen and tried to clean it up. But when I opened the phone’s back cover this discolored impression on the screen went away. Apparently the phone’s battery had swollen up and was putting pressure on the phone’s screen resulting in the screen’s discoloration. If your phone’s Li-ion battery has also swollen then read on.

What causes the Li-ion batteries to swell up like this?
The Li-ion batteries are sealed up batteries. They become swollen up because of the gas build up inside them. The gas is a result of gradual oxidation of the electrolyte with each charging cycle. Because the batteries are sealed, the gas cannot escape and puts the pressure on the battery case to make it look bulged.

Swollen Li-ion Battery

Can we take precautions to avoid swelling up of Li-ion batteries?
Yes, you can take some careful steps to make the battery last longer. For example, if you use the battery’s own charger with the appropriate charging voltage and the current ratings. If you use a charger with higher current rating, then battery will charge faster but eventually it will swell up in a few weeks. Similarly, you should avoid hot and humid weather conditions as charging  your battery in hot environment results in faster oxidation. You should also try not to charge the battery all the time and connect the charger only when the phone gives the warning.

Do all Li-ion batteries swell up?
Some of the batteries that are made of high quality and newer material last longer and generally do not tend to swell up. But some of the cheaper batteries are made from old and low grade material and are prone to swelling faster. Many online retailers buy cheap older batteries and recycle them by putting a sticker on them to make them look new – these do not last even a few months.

Can a swollen battery explode if I keep it charging?
The Li-ion batteries swell up because the charging causes the build up of the gas inside. If you keep charging the battery again and again, more gas will build inside and finally so much pressure is built up that the battery explodes and toxic gases are released. The gases are usually inflammable and can also result in fire.

Can I make a small hole to release the gas and keep using the battery?
The gases are unstable, inflammable and very toxic. They can cause severe health problems and can unexpectedly catch fire. It is not advised that you perform any such experiments with a swollen up battery. Instead, just find a replacement battery for your device and use it.

What should be done if Li-ion batteries are swollen?
Once a Li-ion battery becomes swollen up, it is dangerous to keep using it. You should find a replacement battery and replace the swollen battery with the new replacement. Do not try to further charge the battery anymore. As far as the old swollen battery is concerned, you should follow the local conventions regarding hazardous recyclable materials.