Unlike many toys, your vehicle actually comes with a battery. But your car battery won't keep working without some diligence on your part. Before we get into the maintenance tips, there are a few things worth knowing about automotive batteries, which will help you understand exactly what they do.
About car batteries
The battery stores energy in chemical form that is released on demand as electricity. The energy is used by the vehicle's ignition system to crank the engine, as well as power the lights or other accessories. If your alternator fails, your vehicle can run on the battery alone, at least for a short period of time. Normally, however, as long as your engine is running, the alternator keeps the battery recharged. If you operate any electrical items with the engine off – such as power windows, the audio system or headlights – the battery will slowly drain.
Because automotive batteries contain hydrogen-oxygen gases and sulfuric acid that can cause serious burns, you need to observe some precautions before you handle the battery. The American National Standards Institute recommends wearing safety glasses or goggles and a face shield. Other precautions include never leaning over the battery, working in a well-ventilated area and keeping all ignition sources like cigarettes away from the battery. Now, on to car battery care:
First, if your battery is an older type that's not sealed, it's important to make sure the water level is adequate. It's easy to tell which type you have: unsealed batteries have small vent caps on top that can be easily unscrewed. If the water level is not up to the bottom of the cap, replenish it. For areas where the tap water is hard (with a high mineral content), use distilled water. If you're really not sure if the local water is hard or soft, distilled water is your best and safest bet. Check the water levels often during hot summer months, as heat tends to evaporate water more quickly. If the battery water level is allowed to get too low, the heat generated within the battery will destroy the battery cells.
Next, visually check the car battery terminals (one is marked positive "+" and the other is marked negative "-"). Before cleaning the connections or removing the battery, disconnect the negative terminal first whenever you disconnect the battery cables from the terminals. Removing the positive connector can cause a spark, especially if you're using a metal tool that comes in contact with any piece of metal on the car. The spark can create an ignition source that could cause the battery to explode.
If the terminals are encrusted with deposits, clean them with a wire brush dipped in baking soda and water. These deposits can block the flow of electricity. Make sure not to splash any of the baking soda/water solution on the vehicle's paint surfaces. Now, check the battery cable ends. A loose battery cable does an excellent impersonation of a totally dead battery. If there is any movement of the battery cable end that is attached to the terminal, it is too loose and needs tightening.
Make sure the brackets that hold your battery in place are tight. Loose brackets will cause the battery to vibrate when the car is running and this constant vibration will shorten the life of the battery. It's also wise to check the condition of the battery tray for corrosion. The function of the battery tray can be undermined if corrosion is apparent and isn’t stopped. If there's minor corrosion, brush it off and apply an acid-resistant paint to the tray. If the tray has been weakened by corrosion, replace it. The condition of the tray and brackets is vital to keeping the battery from tipping over under the hood – a rare, but not unheard of mishap. A secure tray can also prevent excessive vibrations from damaging the battery.
If you need to recharge your car battery, the best equipment is a trickle charger, preferably left on for eight to 10 hours or overnight. If your battery is unsealed, remove the vent caps and place a damp rag across the openings. Attach the alligator clips on the charger to your battery. The red clip should be attached to the positive terminal and the green or black clip should be attached to the negative terminal. If your battery is sealed, there should be a charge indicator window on top. The battery needs charging if the window is green or dark. Your battery needs to be replaced if the window is clear or yellow.
Unless the battery manufacturer indicates otherwise, the average life of a battery is about four years. So, if you want to enjoy several years of confident vehicle starts, follow these simple maintenance tips and check your battery water levels, terminal, bracket and tray condition about every two months.