What Are the Main Reasons Batteries Fail?

Power - by Joe Weber - updated on 9/9/2022

Batteries can be a huge investment depending on what they are being used for and can even reach upwards of $1000 for high-end batteries. Understanding the reasons batteries might die before they should is key to making sure they last as long as they can. Read on to be able to recognize some of the common areas where batteries fail and how to protect your investment.

What Are the Most Common Causes of Battery Failure?

There are many reasons that batteries can fail too soon. Below is a list of the most common causes of early battery failure.

• Plates are key to battery life and the chemical reactions necessary for a battery to work can slowly corrode them. This leads to one of the most common reasons batteries fail: internal short circuits. This occurs when the plates physically touch each other inside the battery.
• Batteries are designed to be installed and used in applications that are generally near room temperature, usually around 77 degrees. Constant use or storage in extreme heat or cold can cause batteries to fail early.
• Repeated cycling from full charge to full discharge and back to full can cause a loss of active material from the positive plates reducing the capacity and useful life of the battery.
• Overcharging the battery can cause excessive heat and gassing in the battery which can cause a reduction in active material on the plates and even warp the plates.
• You would think that if overcharging is bad then undercharging is good, right? Wrong. Undercharging your batteries can cause sulfation which leads to lower power output and is not fixable under normal charging conditions.
• Some batteries, like AGM, are better than others in terms of vibrations resistance but all batteries have a limit. Excessive vibrations and rough conditions can cause loose connections, internal component damage and casing damage.
• Most batteries are designed for specific applications. Using batteries for applications other than what they are intended for can result in a shorter life.
• Not storing batteries properly when they aren't being used can reduce battery life. Every battery loses charge as it sits unused, roughly 1%-5% per month. This is called self-discharge. A battery maintainer should be used whenever possible when storing batteries long-term to keep batteries healthy.

How Do I Keep My Battery in the Best Condition?

To make sure your batteries stay healthy and last as long as possible there are some easy things that you can do.

The easiest step for car batteries is very simple and self-explanatory. Drive your car; the longer the better. It's simple. If you drive your car the alternator will charge your battery so it's near full at all times. Driving the car often and using anti-corrosion spray and terminal protectors will greatly reduce the chances that your battery will fail early. Some lead batteries, like AGM, have larger plates that are more durable and prevent corrosion leading to longer battery life.

If you don't drive your car often or it sits for several months at a time, a battery maintainer is necessary to keep the battery charged to the optimal level for storage and prevent the battery from sulfating so it's ready to go when you need to start the car.

Electronics draw power from the battery even when they are turned off before you shut the car off. To extend the life of your battery it is recommended to unplug any accessories that you have so they don't draw any current from the battery when that car isn't running.

What Do I Do if My Car Battery Dies?

If you follow all of the rules and maintain your battery as best as you can you may still find yourself in a situation where your battery is dead and your car won't start. If you find yourself in this situation it's always a great idea to have a small, lightweight jump starter in your car. After you get your car started drive over to your local Batteries Plus to have our store experts test your battery free of charge. If it is time for a new battery our store associates will help you find the best battery for you.

For more information on your vehicle battery please read our blog article titled "How Do I Know Which Car Battery Fits My Car?". Some batteries can come back from the dead. Read our article "Can You Revive a Completely Dead Car Battery?" for tips and tricks on how to revive your battery if it's been sitting and is now dead.