Frequently Asked Questions About Car Batteries


Just about everyone of us at sometime has been stranded either at home or worse on the road with a battery issue.  And it always happens at the most inopportune time guaranteed! So is there anyway to avoid getting stranded? You bet! I’ve compiled a list of frequently asked questions that will cover most battery related issues. I hope you find this helpful.   

1. How long should a battery last?

The average lead acid automotive battery will last about 4 to 6 years, depending on the quality and use.

2. When should I  replace my battery?

Batteries most often die a slow death, which means over time the available amperage will slowly fall below the batteries rating.  For example, a new battery that’s rated at 500 cold cranking amps or CCA, will test at or above its advertised rating, say 550. But over time the tested amps will slowly fall below it’s rating and will reach a point that it should be replaced, usually around 25% below original CCA rating or around 375.  Which brings us to our next FAQ.

3. Will my car give me any warning signs before had or will I just get stranded?

Maybe if you’re tuned into your car you might notice the starter sounding weak for the few seconds it’s engaged. It will sound different as the starter RPM is decreased due to lower available amps.

4. How often should I have my battery checked?

Every oil change. Have your mechanic do a simple battery test which will determine the voltage and more importantly the available amps or CCA’s. A good shop will do this every time and can predict when your battery will need replacing.

5. Can I test my battery myself?

Absolutely! You really don’t have to spend a lot of money, a simple voltmeter will do. The battery voltage is a very good indicator of “state of charge”. This shouldn’t replace having your shop test available amps, but it doesn’t hurt to test the battery yourself. A rule of thumb with testing voltage….

Car Batteries

               12.7 volts or higher indicates a fully charged battery

               12.4 indicated 75% state of charge

               12.2 50%

               12.0 25%

               11.8 or lower 0% charge or basically dead

6. What can I do to extend the life of my battery?

Since all automotive batteries are “maintenance free”  the best advice I can give is never let the battery lose state of charge. The absolute worst thing you can do is leave a vehicle unattended for weeks on end with the battery connected and no means of charging.   If you know the vehicle is going to be out of service for a extended period of time, then it’s best to leave the battery connected and install a low amp battery charger with automatic start/shut off. A battery in a low voltage state will sulfate or basically corrode internally which will drastically reduce it’s usable life. Last but not least “keep it clean! Corroded terminals and dirt/grease on the battery casing both will cause issues if left unattended. To clean battery use specialty battery cleaner found at any auto parts store, follow directions and flush with water good when finished.