Popular Mechanics Podcast

Your car battery should last about 3 to 5 years…

But lots of people find that they need to modify their car battery every 1 to 2 years.

Why is this?

And what can you do to prolong your vehicle’s battery life?

We’ll show you why automobile batteries die early…and what you can do to keep this from happening.

We’ll also offer you 8 simple tips and tricks to maximize the life span of your car’s 12 volt battery.

The tips we’ll teach you in this article will be simple to do…and anyone will be able to perform these (even if you know nothing about cars or car batteries).

So let’s begin! …

First, You Should Know That Every Car Battery’s Lifespan Has A Limit (however most people kill their battery well before it’s time)

Even if you care for your car battery perfectly…it will still die one day.

This set lifespan is known as the battery’s”Calendar Life” and it’s completely independent of how many times the battery has been charged or discharged.

But most car batteries never make it their full”Calendar Life”…

Rather, they die early due to poor maintenance and care…that you can do something about.

Lead acid batteries are the earliest, most reliable, and most widely used type of rechargeable battery in the world.

Lead Acid Batteries have three life phases — formatting, peak, and decline.

  • Formatting is when the battery is new and needs to be used lightly.

  • Peak is the ideal performance stage, which we seek to maintain for as long as possible.

  • Decline is a slow process, but one that slowly ends in the conclusion of the battery.

Batteries in decline can still be used for quite some time, but have to be watched.

Around this time, you may either recondition the battery or keep a close eye on it and try to replace it until a problem arises (like being not able to begin your vehicle for work).

Tip 1: Do a monthly review of the battery terminals to make sure they’re clean and rust free.   One of the initial problems most people have with their car battery is the build-up of rust around the terminals.   Corrosion destroys the connection between the battery and the vehicle and several batteries are replaced due to a lot of corrosive build up.   But often times, this is readily treated simply by pouring a small amount of Cola or a DIY anti-corrosion paste (one part water to three parts baking soda) over the corroded areas. 

The acid in the Cola or the alkaline properties at the DIY anti-corrosion paste will eat the rust away.   Be sure to allow it to dry, then rub some petroleum jelly on the terminals to prevent future corrosion.

Tip 2: Do not run any car accessories (radio, lights, or electronics) before turning to the vehicle ignition and driving the car.   When the vehicle is on, the car alternator generates electricity and charges the vehicle battery after the battery has a voltage drop.   But if the car isn’t on, and you’re using the car’s electronics, you are simply relying on the car battery to power those electronic equipment. 

This is damaging to the car battery because car batteries aren’t meant for this sort of use.

Rather, car batteries are supposed to offer a sudden burst of electricity for ignition.  They are not made to offer prolonged power for electronics and other devices (that is what a deep cycle lead acid battery could be for).   Using your car battery as a battery which powers electronics, instead of a battery that just gives you a burst of power for ignition, will damage the battery and significantly shorten it’s lifespan if it is repeatedly utilized in this fashion.   So avoid operating any car accessories or electronics while the car is off.

Tip 3: Make sure the car battery is secure and has good battery cables.   The battery has to be secured at all times.  If a battery is jostling around it will be impaired and might short circuit.   This will ruin the battery and even cause damage to your car whilst creating a security risk.   The same could happen when you have awful battery cables (or they’re not connected correctly ).  So check your cables and make sure they have a secure connection as well.

Protecting your vehicle battery from big changes in temperature will help optimize the battery’s lifespan.   To do this you can use a car battery insulation kit.   Newer model cars already have these kits installed typically.  But if your car does not have one, you can easily install one yourself.   Just make sure it fits your car’s battery compartment.  Generally the companies selling these battery insulation kits will have a form on their website where you can put in your car model and year, and it will tell you if your battery will match their kit — like here (top of page).   These protective battery sleeves are typically made of plastic or an acid resistant, thermal resistant material.   These automobile battery insulation kits will insulate your battery and protect it while still allowing proper ventilation.

Tip 5: Fully charge your car battery at least once a week (use a car battery charger or shut-off if you have to).   Your car battery drains even when the car is off.  That happens because current is drawn from the battery by car accessories (radio, lights, etc.) or the automobile computers.   This is why people come home from long vacations and find their car battery dead.   But to prevent this, you can use either a car battery charger or a solar battery charger. 

Car battery chargers (regular or solar) will keep the optimum charge level of your car battery when the car is not being used.   They do this by providing enough power for your car accessories and car computer, so that they don’t continuously draw current from the car battery when the car is off.   They’re also useful if you go on plenty of short car trips (like to work and back each day) and never give your battery a opportunity to fully recharge.  Repeatedly doing this can dramatically shorten your battery’s life — unless you use a car battery charger or interchange batteries, leaving one at home to fully charge.   The main thing to remember with this tip is…be sure you fully charge your car battery at least once a week because it’ll greatly increase the life of your battery.  Do this using a charger, interchanging batteries…or just going on a car ride long enough to recharge the battery.

Tip 6: Check your car battery’s water level.   Most car batteries indicate if there’s a need for water.   So check the vehicle battery water level indicator frequently and if water is required, refill the battery with distilled water (and that’s significant, ONLY use distilled water to refill your vehicle battery).

Tip 7: Do NOT overcharge your car battery.   Lead-acid batteries release oxygen and hydrogen gases when they are overcharged.   This causes two problems:

  1. It can be explosive.

Tip 8: Assess your car’s alternator.   If you’re doing everything we have recommended in this article but your car batteries are dying early, you will want to check your car’s alternator (or get a mechanic to check it).   If your alternator is bad it will results in ineffective recharging of your battery and dramatically shorten your battery’s lifespan.