Turn off the device and remove the batteries
Wear gloves and eye protection
Dispose of leaking or damaged batteries properly
Use a dry brush or cloth to remove loose corrosion
For alkaline battery corrosion, apply white vinegar or lemon juice to a cotton swab
For acid battery corrosion, use a baking soda and water paste
Gently scrub the affected area with a toothbrush or cotton swab
Wipe the area clean with a damp cloth
Dry the area completely
Clean contacts with isopropyl alcohol
Let everything air-dry before inserting new batteries
Replace the batteries with fresh ones
Check for damage if the device still does not work