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How to prepare your car's battery for winter

Three ways to make sure it stays charged and delivers cranking power for starting your car.

Brian Cooley Editor at Large
Brian Cooley is CNET's Editor at large and has been with the brand since 1995. He currently focuses on electrification of vehicles but also follows the big trends in smart home, digital healthcare, 5G, the future of food, and augmented & virtual realities. Cooley is a sought after presenter by brands and their agencies when they want to understand how consumers react to new technologies. He has been a regular featured speaker at CES, Cannes Lions, Advertising Week and The PHM HealthFront™. He was born and raised in Silicon Valley when Apple's campus was mostly apricots.
Expertise Automotive technology, Smart home, Digital health Credentials
  • 5G Technician, ETA International
Brian Cooley
2 min read

Winter is really hard on car batteries, causing them to charge more slowly while driving and perhaps come up short on the cranking power needed to start your car's engine. Add to that the fact that winter's dark, short, cold days are arguably the worst time to be stranded and you'll want to take 15 minutes to do some dead battery prevention right now.

Gather up these tools and supplies:

Put on the gloves because batteries tend to be dirty and sometimes toxic to the touch. Using the wrench carefully to not let it make a circuit between battery terminals or to the metal of the car, loosen the negative or black battery cable clamp first and secure that cable so it won't jump back into position. Then remove the positive or red cable clamp and secure that cable similarly. 

Battery terminals

Be careful not to let the metal wrench short the two battery terminals together or short the red terminal to body metal on the car. 

Brian Cooley/Roadshow

Using the female part of the terminal brush, clean the two terminals on the battery with a twisting motion so they're shiny and free of debris. Use the male side of the brush the same way on the inside of the battery clamps you removed in the step above.

Battery terminal cleaning

Brush clean the outside of the battery terminals and inside of the clamps that attach to them.

Brian Cooley/Roadshow

Install or replace the round felt pads that sit at the base of each battery terminal. Reattach the cable clamps, starting with red and then black. Tighten each of them moderately with the wrench, but not as much as you would a typical fastener since the cable clamps are made of soft metal. Again, be careful not to let the wrench connect the battery terminals to each other or metal in the car. 

Spray each terminal with the protectant spray. If your positive or red terminal has a protective plastic or rubber cap, snap it back into place now. 

Barring any less common problems in your battery circuit, it's now ready to charge well and deliver maximum juice to turn your engine over on a cold day. 

Watch the video above for a few more of my tips on how to drive your car for battery health and whether to use a trickle charger. I don't -- but I'll show you what I do instead.