What is the white crusty stuff that forms, for instance, in a flashlight, when the Alkaline batteries leak? How do you get rid of it? - Quora
![Old alkaline household batteries leak a white crusty substance made of potassium carbonate (K2CO3 Stock Photo - Alamy Old alkaline household batteries leak a white crusty substance made of potassium carbonate (K2CO3 Stock Photo - Alamy](https://c8.alamy.com/comp/FJTPC8/old-alkaline-household-batteries-leak-a-white-crusty-substance-made-FJTPC8.jpg)
Old alkaline household batteries leak a white crusty substance made of potassium carbonate (K2CO3 Stock Photo - Alamy
![I found an old light I haven't used in years. Didn't work when I turned it on, and checking the batteries I saw this white stuff on a few of them. When I found an old light I haven't used in years. Didn't work when I turned it on, and checking the batteries I saw this white stuff on a few of them. When](https://i.redd.it/fvb304n6gdp31.jpg)