How To Easily And Safely Clean A Car Battery With Common Household Items

Most of us make it a point to do routine cleaning on the interior of our cars including seats, glass, carpets, and even door pockets and cupholders. Our regular maintenance schedule also includes oil and transmission fluid changes as well as safety inspections and other necessary upkeep. But one often overlooked bit of work that's very easy to do can leave you stranded if neglected for too long. 

Battery corrosion can build up quickly, and just a little bit of regular attention using some common household items can help ensure you're not stuck in a dark parking lot behind the wheel of a vehicle that won't start. Cleaning your battery terminals doesn't take long, but it's a good idea to do it regularly, and you'll want to gather all the necessary supplies before you begin to work.

What you'll need:

  • household cleaning gloves
  • petroleum jelly or WD-40
  • baking soda
  • an old toothbrush or other soft-bristled nylon brush (one you can throw away when you're done)
  • water and a plastic container
  • rags or towels
  • wrenches or sockets for your battery terminals (usually 10/12mm or 1/2 inch)

Cleaning your car battery terminals step-by-step

To begin, turn your engine off and open the hood (or the rear cargo area if that is where your battery is located — consult your owner's manual).

  1. Carefully inspect your battery for any swelling, leaking fluid, loose posts, cracks in the plastic, or other obvious signs of damage. If you notice any of these, have your battery replaced immediately.
  2. If your battery appears to be in good condition and just has some bluish-green powdery deposits around the terminals, this is just ordinary corrosion from the terminals. Moving back and forth with normal vibration and a little bit of effort will restore a proper connection. 
  3. Disconnect the negative (black) battery terminal, followed by the positive (red) battery terminal.
  4. Make a cleaning solution by combining one tablespoon of baking soda with water until thoroughly mixed.
  5. Dip the brush in the cleaning solution and scrub each battery post and the area around it until all of the residue is gone. Wipe the area clean with rags as you go.
  6. When everything is clean, rinse the terminals with a spray bottle or a damp rag and dry them thoroughly.
  7. After everything is dry, coat the terminals with a thin layer of petroleum jelly or WD-40 and reattach the battery terminals, positive side first, and tighten them down.