Corroded batteries can be a problem. Restricted access to the battery compartment of a flashlight makes the task of removing a corroded battery more challenging. Not only does corrosion from the batteries make a mess inside the flashlight, but the batteries may swell, causing them to become stuck. By using vinegar or lemon juice and baking soda, you may neutralize the corrosion and safely remove the batteries.
Removing the Batteries
Remove the head piece from the flashlight. This might include removing several different pieces depending on the flashlight's brand.
Fill the shaft of the flashlight one-quarter full with vinegar or lemon juice and pour approximately 1 tablespoon of baking soda into the shaft. This mixture neutralizes the acidic battery corrosion.
Cover the open end of the flashlight with plastic wrap or tin foil.
Gently shake the flashlight so that the neutralizing agent can thoroughly cover the inside of the shaft.
Remove plastic wrap or foil and pour the contents of the flashlight out. If the batteries do not come out, gently tap the flashlight on a hard surface to loosen them up.