You keep your car running by doing preventive maintenance, including changing the oil regularly and checking all the fluids. But one area you may not pay attention to is your car's battery. A car battery is a hot bed for corrosion. The acid in the battery escapes from the device and builds up on the battery terminals over time. There is an inexpensive method to prevent battery terminal corrosion--applying petroleum jelly to each of the battery terminals.

Petroleum Jelly
• An inexpensive way to keep corrosion from building up on your car's battery terminals is to apply a tablespoon of petroleum jelly to both the positive and negative posts. Use a wrench to remove the battery cables from the posts, and rub the petroleum jelly onto each terminal. Wear latex gloves to keep your hands from getting greasy. Install the positive (red) cable first, then the negative (black) cable when you are reconnecting the battery.
Anti-Corrosion Washers
• Anti-corrosion washers, which you can find at auto parts stores and retail superstores, is another inexpensive way to keep corrosion from forming on your car's battery terminals. The washers are felt pads that contain a specially formulated chemical that prevents corrosion. Remove the battery cables, slide the washers on and reconnect the positive cable first, then the negative.
Dielectric Grease
• A tablespoon of dielectric grease will also prevent corrosion from building up on your car's battery terminals. You'll find dielectric grease at auto part stores, hardware and home improvement stores. To apply, disconnect the battery cables and apply the grease to each terminal.
Cleaning Corrosion
• Before applying petroleum jelly, anti-corrosion washers or dielectric grease on your car's battery terminals, first clean off any corrosion that is present on the terminals. Mix 2 tsp. of baking soda and 2 cups of water in a pot. Then disconnect the battery cables, wrap them in a rag and place them away from the battery. Pour the baking soda mixture onto each corroded battery terminal. The baking soda will neutralize the acidic deposits. Let the mixture sit on the terminals until you see the corrosion break away. Wear work gloves and use a stiff brush to rub off any remaining corrosion. Dry each terminal with a clean rag or shop towel after the corrosion is gone. Reconnect the battery cables, and turn on the car to test the battery and connection.
You can also remove the battery from the car and sit it on a non-concrete surface and pour the baking soda mixture over each terminal.
These I believe will prevent terminal corrosion in batteries and keep our maintenance up to upgraded.