Learn the causes and effects of battery terminal corrosion and how to fix it with baking soda, soda, or sandpaper. Find out how to prevent it with new battery, copper clamps, and anti-corrosive sprays. 1. Hydrogen gas leakageThe battery turns acid into an electric current. Sometimes, the hydrogen g. Now, that we know what causes car battery corrosion, we need to know how to fix it. There are some different methods you can use to clean the battery terminals. The best way to prevent battery terminal corrosion is to make sure the alternator is not overcharging the car battery. You also want to have a newer car battery in good condition. Anti-co.