If you would like to keep your batteries working at optimal performance, heres a tip for you. Unscrew the cartomizer from your battery and using a Q-tip gently wipe it around the inside threads of the battery (see picture 1 and 2). Picture 1 Picture 2 This will remove any build-up of liquid, dust, and dirt (see picture 3). Picture 3 This build-up can prevent the battery from accepting a full charge from the charger and can also prevent the battery from making a good connection with the cartomizer. This can result in reduced battery life and a decline in flavor and vapor production. So if you want to keep your SmokeStik working factory-fresh, please remember to keep the threads clean.