An auto battery is built up of six cells, each containing stacked positive and negative lead plates. These are divided and separated by insulators and immersed in an electrolyte, a liquid blend of sulfuric acid and water. However, some batteries, use a gel instead of the electrolyte. This is considered to be safer and because you do not have to refill it with electrolyte, it has been labelled “maintenance-free”. Each cell stores 2.1 volts for a total of 12.6 volts.
Between the electrolyte and the lead plates, a chemical reaction is created. This produces dangerous, explosive gases that vent through the battery cover vents. Because of this, caution should be taken when you charge or jump start a low battery. The same caution should also be taken every time you are working under the hood of your vehicle. It is important to provide as good ventilation as possible in the battery, so always keep it clean. All batteries, even those using gel instead of electrolyte lose charging capacity as the time passes. The reason for this is that the chemical breakdown of the connections inevitably takes place leading to the deterioration of the plates and loss of the electrolyte.
When your vehicle has start up or charging problems, the vehicle troubleshooting procedure should start with a test of the battery. You do that with a visual check followed by a voltage test. If the battery is ok, other components of the electrical system is probably the reason, but battery problems are by far the most likely reason.
A good thing with battery checking and trouble shooting is that you need very little technical equipment. All you need is a good, old Digital Volt Ohm Meter and a charger for the battery.
Each auto battery manufacturer uses a certain color in the battery ‘eye’ which tells whether a charge is needed. This is a fast and easy way to alert you for re-charging. Check out your battery manufacturer’s specification of the ‘eye’ and everything associated with it.
If you need to replace your auto battery, always test it before you replace it. Also test the entire electrical system of your car. The reason for your battery problem might be a weak alternator or a drain on the system and if this is the case it won’t take many weeks before your have to replace the new one as well. What seems to be a battery problem is not always caused by the battery itself.