YES! Please do not use or charge a swollen or misshaped battery. Please Dispose of it properly.
So you know what to avoid: common causes of swelling are:
- completely discharging
- over-heating (like leaving them in a hot car)
- improper storage:
- fully charged
- fully discharged
- too cold
- too hot
- where it can get wet
- and sometimes once they've have passed 150-250 cycles wherein they need to be replaced - which, depending on use, could be from 6 months to 2 years.