Corroded battery cables don't just look bad under your hood - corroded cables also limit the amount of current flowing to and from the battery. That doesn't only make it harder for your battery to turn the motor over; it also makes it harder for the alternator to charge your battery while you drive. It is a lose, lose situation.
Car batteries consist of a series of lead plates suspended in an electrolytic solution. When your battery supplies power to the motor, tiny droplets of electrolyte escape from the base of each terminal post. These droplets of electrolyte land on your battery terminals, and corrosion occurs.
Cleaning up this mess is quick and easy. You need paper towels, baking soda and water solution, a wire brush, a toothbrush and some petroleum jelly or dielectric grease. The baking soda and water solution should be 1 part baking soda to 4 parts water, but it doesn't need to be exact. Before getting started, put on gloves and safety goggles to prevent contact with any battery acid on your skin or eyes.
Disconnect your battery, negative cable first, then the positive cable. If the corrosion on your cables is heavy, wipe off as much as possible, using the paper towels. Once that's done, you can either soak the ends of the cables in the baking soda and water, or just brush some on with the toothbrush. While the baking soda does its work, you can wipe off the battery posts. After removing any loose corrosion or grease, use the wire brush to knock off any stubborn remnants. Finally, brush the baking soda and water solution on the posts and top of the battery, and wipe dry with paper towels.
Remove the battery cables from the baking soda and water. They should look like new by now. If not, scrub them with the toothbrush and rinse in the baking soda solution. Dry the cables off and reconnect to the battery, in reverse order: positive cable first, negative cable second. After tightening the terminals to the posts, apply a light coat of dielectric grease or petroleum jelly.
Your car battery and cables are easily forgotten under the hood. To avoid a repeat of the corrosion build-up, make a note on your calendar to inspect the connections every 4 months.
