Based on your description, it sounds like the battery might be experiencing several potential issues. Firstly, it’s possible that the battery has reached the end of its lifespan and needs replacement. Additionally, there could be issues with the charging system, such as a faulty charger or inadequate charging current.
To troubleshoot, start by checking the connections to ensure they are secure and clean. Then, test the charger with a different battery to see if it charges properly. If the problem persists, it’s likely that the battery itself needs replacing. Remember to dispose of the old battery properly according to local regulations for handling hazardous materials.