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Battery Maintenance

Today’s vehicles have more electrical demands than ever, and batteries play an essential role in meeting those demands. The battery supplies the electrical current that the starter motor requires to start the engine. It also provides power to the electrical components and accessories when the vehicle’s engine is not running. When the electrical load exceeds the charging system’s capacity, the battery steps in to supply the extra current required. The battery also acts as a voltage stabilizer for the entire electrical system.

Do-it-yourself maintenance can play an essential role in maximizing the life of your battery. It is also important to have your battery and charging system checked at least once a year. Early detection of a weak component can save you time and money. Look for a AAA facility near you that has the proper testing equipment to perform a complete check of your vehicle’s battery, as well as your vehicle’s charging and electrical systems.

Battery Safety

Although batteries may appear to be uncomplicated, they can be one of the most dangerous components to service if you are not careful and cautious. Follow the precautions listed on the battery and in your owner’s manual.

To avoid injuries when servicing your battery, follow these precautions:

  • Always wear eye protection and gloves.
  • Avoid dropping the battery. Batteries are heavy and, if dropped, may cause injuries.
  • Avoid tipping the battery. Batteries contain sulfuric acid that may spill out and cause burns.
  • Never smoke or expose the battery to a spark or open flame. Explosive hydrogen gas is present and may ignite.
  • Remove all jewelry. If your watch or ring touches a battery post an explosive spark or burn may occur.
  • After handling a battery, wash your hands with soap and water. You may have come into contact with some type of battery acid. Washing your hands will help neutralize the acid.
  • Never place tools on top of the battery. Tools can cause a short across battery posts or cables.

Battery Inspection and Service

Whether you have a vent-cap battery (one that allows the caps to be removed to add fluid) or a “maintenance-free” battery (one that is sealed) regular maintenance is required to ensure your battery works safely and effectively. Many batteries are labeled as maintenance free, but are actually serviceable. You should check the electrolyte level and add fluid, as needed.

Keeping Your Battery Case Clean

The simplest maintenance procedure you can perform is keeping the battery case clean. Dirt and residue can cause a current drain on the battery. Clean the battery case by wiping it with moist paper towels and a mild detergent.

Checking the Electrolyte Level

Electrolyte is a solution of sulfuric acid and water that is inside your battery. If the battery has removable vent caps, remove the caps and check the level of the electrolyte monthly. The level of the electrolyte should rise above the top plates of the battery. If fluid is needed, add distilled water being careful not to overfill the cells. Distilled water, unlike tap water, is pure and contains no mineral deposits that may adversely affect the life of your battery.

Positive and Negative Terminals

There are typically two ways to distinguish positive from negative:

  • Color-codes: red for positive and black for negative.
  • Symbols: + for positive, – for negative.

On post-type terminals, the positive post is the larger of the two. Don’t pry the cable clamp from the battery post. Prying may harm the battery case or cause internal damage. Check the battery’s posts and terminals for loose connections and cracks.

Attaching Battery Cables

Always install the positive cable first, then the negative cable.

Removing Battery Cables

Always remove the cable from the negative battery terminal first, then the positive.

Removing Corrosion

To identify signs of a failing battery, you should inspect your battery case for cracks and bulging. You also should look for corrosion around the battery terminal connections and battery hold-down. If corrosion is detected, clean it off using a 50/50 solution of baking soda and water applied with a small, stiff brush. After removing the corrosion, rinse your battery with clean water. Catch the used water in suitable container – a plastic drain pan works well – and dispose of it properly.