Electronics use Lithium batteries that are quite volatile when punctured. A swollen battery not only causes charging issues, but it can be dangerous. When a battery is punctured, it will emit a gas that isn't safe to inhale and very possibly start a small fire. Do not squeeze the battery or use metal or sharp tools to pry it out of the laptop. If you notice your laptop case splitting or the battery bulging, it's best to put the entire unit somewhere away from flammable material and contact the manufacturer for device-specific instructions. If you feel comfortable removing a swollen battery, you need to dispose of it at a facility designed to handle Lithium batteries.