How To Predict The Life of Your Car Battery


It is possible to predict the useful life of a conventional 12 volt automobile batteries. Most people just wait until the battery fails and then replaces it. Unfortunately it can fail at the most inopportune time thus causing an inconvenience, potential financial loss, or possible danger to the driver.

Batteries should be maintained and kept clean. The terminals should be free from corrosion and those with removable cell caps, should have distilled water added to them when needed.

Still, a battery can fail at almost any time. Typically, a battery should give at least 36 months of service. After that you are prone to failure at any time. The better brand or quality of the battery doesn't necessarily mean the battery will last longer. It just means they will warranty it or pro-rate it.

There is a way of monitoring the battery so you can predict the end of life of the battery. By measuring the voltage of a stabilized battery you can get a better picture of the life of the battery with a good quality digital voltmeter either across the battery or through the cigarette lighter. To measure a stabilized battery, check it only after the car has been sitting overnight in temperatures between 60 and 90 degrees. When a battery is new, the stabilized voltage should be around 14.80 volts.

It is a good idea to record the date and voltage every six months or so. This way you will have a track record of the life and be able to predict its life.

If the stabilized voltage is 12.9 or less, the battery is almost dead and should be replaced soon. The vehicle will start and run but the battery does not have the capacity to handle any loads such as lights, wipers and heater on a cold winter night and especially in traffic.

There are other factors that can shorten the life of an auto battery. Loose or worn fan belt, defective alternator or regulator, shorted starter motor, untuned engine that causes long cranking times. External accessories. Short drive times.