Like any other part of your car, the battery goes through wear and tear over time. By checking the battery regularly, you can make sure that it continues to run effectively and last longer. A battery that's clean runs a lot better than a dirty and cruddy one.
Checking your battery is something that you can do yourself, but there are some safety measures that you should take before you get started. Here's the caution list:
1. Don't smoke while checking the battery.
While checking your car battery, don't hold a cigarette in your hand or have a lit cigarette in your mouth. Bottom-line is, don't smoke while working on your car battery. Your car battery contains acids and produces gases that could be very dangerous if combined with fire. If any of these corrosive acids touch your skin, wash them off right away with water.
2. Shut off the engine.
3. Remove the negative cable.
Removing the negative cable prevents you from getting electrocuted and keeps you from damaging your car's electrical components. When removing or replacing the battery cables, always remove the negative cable first and replace it last. If you remove the positive cable first and it touches something metallic, it will fuse with the metal part that it touched.
You can remove the cables by undoing the nut on each cable clamp and working the cable off of the terminal post.
4. Tie the cables back while working on the battery.
While working with the battery, keep the cables from touching anything metal by tying them back. You should also make sure that nothing metallic touches the terminal posts which can damage the battery.
Don't let the caution list put you off from giving your car battery the maintenance that it needs. A simple visual inspection will already tell you a lot. Here are some of the trouble spots that you should look out for.
1. Powdery deposits on the positive and negative terminals (cell connector corrosion)
The deposits are made by battery acid. Before cleaning it off, you will need to remove the cables (negative first). Sprinkle some baking soda on each terminal. Using an old toothbrush that's been dipped in water, you can scrub the deposits away. You can also use a battery terminal brus if you have one. A soap-less steel wool pad will also do the trick.
Before replacing the terminals, you should coat the terminals with thick automotive grease or maybe petroleum jelly to prevent any more corrosion from forming again.
2. Frayed or broken cables
Frayed or broken cables can cause your battery to short-circuit. You will need to take your car to an auto repair shop and have the cables replaced. If the cables show extensive damage, you should have them replaced immediately.
Use an old toothbrush or a clean, disposable, lint-free rag to get rid of the dirt.
4. Cracked case or cracked cell cover
If your battery case or cover is cracked, you need to take it to an auto repair shop and have it replaced.
5. Loose hold-down
Tighten the nut. A loose hold-down is an accident waiting to happen.
It's not good for your car battery to be wet. You can dry it with a clean, disposable, lint-free rag.
If you don't have the time or skill to do your own battery maintenance, you can just hire a professional auto mechanic to clean, maintain and or replace your car batteries if needed.
Resource: How to Check Your Car Battery for Trouble Spots