You Probably Need To Clean Your Car's Battery Terminals - Here's Why

We've all climbed into our cars, turned the key, and heard the car struggle to start. While sometimes this happens as the battery ages, hard starting can also be due to the buildup of corrosion around the battery posts and terminals. If you open the hood and look at the clamps on your battery posts, you might notice a blue-green or white powder collecting on them. 

That buildup is a natural occurrence from the chemical reaction that takes place as the sulfuric acid from the battery releases hydrogen gas, which mixes with the moisture and salt in the environment to create the corrosive buildup. This problem will get worse as your battery ages and will speed up in hot weather or if there is a crack in the battery's plastic case that causes fluid to leak out. A swollen or cracked case is a sign that your battery needs replacement immediately; if you notice either of these signs, get to an auto parts store and purchase a new battery.

Even if the case is intact, corrosion will slowly eat away at the metal on the terminals and affect their ability to make good contact with the battery posts, eventually leading to the point where your car will not start.

You should clean your terminals regularly, but over time, you may notice that you cannot re-tighten them as well as you could when they were new. This probably means the corrosion has eaten away at the mating surface inside the terminals, and it is time to replace them. You can purchase new terminal clamps for a few dollars at most auto parts stores or Amazon.

 If you're uncomfortable swapping them out, a reputable and honest mechanic should change them for you for a nominal charge. If you find that even after buying new terminals, you can't tighten them adequately, that could mean that the corrosion has eaten away at the posts themselves, and it's also necessary to replace the battery. However, this is rare and can be prevented with a bit of regular cleaning and maintenance.