How Do I Know If My Battery Is AGM

How Do I Know If My Battery Is AGM?

There are several different types of batteries on the market, each with a special set of features and applications. The Absorbed Glass Mat (AGM) battery is one type of battery that is gaining popularity. These batteries are a great option for a variety of applications because of their high performance and long lifespan.

It can be challenging to determine whether or not you have an AGM battery, though, if you are unfamiliar with them. In this article, we’ll examine AGM batteries in more detail, covering their identification, testing, and maintenance requirements.

What is an AGM Battery?

An absorbed glass mat separator is used between the electrodes in sealed lead-acid batteries known as AGMs. AGM batteries are more dependable and require less maintenance than other lead-acid battery types thanks to the separator’s ability to prevent acid leakage.

AGM batteries are renowned for being able to store a lot of energy in a relatively small space, or for having a high energy density. AGM batteries are also frequently used in a number of different applications, including solar energy systems, boats, recreational vehicles, and even some cars.

AGM batteries’ long lifespan is one of their greatest benefits. The typical lifespan of an AGM battery is 3 to 5 years, which is significantly longer than that of a conventional lead-acid battery. AGM batteries are additionally renowned for their high performance. They are perfect for a variety of applications because they can withstand both high charge rates and deep discharge cycles. AGM batteries might not be the best option for all applications due to the fact that they are also more expensive than conventional lead-acid batteries.

How to Identify an AGM Battery

AGM batteries can be distinguished from other batteries by a few distinctive features. First of all, AGM batteries are usually sealed, so they lack a removable cap that would allow you to add water or check the electrolyte level. Second, compared to conventional lead-acid batteries, AGM batteries typically tend to be smaller and lighter. You can also check the label or manufacturer information, which should say whether the battery is an AGM or not.

Measuring the voltage and capacity of a battery is another method of identifying an AGM battery. AGM batteries typically have a capacity of 100 to 200 amp-hours and a voltage of 12 volts. The manufacturer’s specifications should always be consulted because these values can change depending on the particular battery.

How to Test an AGM Battery

With a few simple tools, testing an AGM battery is fairly easy to do. You should run a voltage test as your first test. This test determines the battery’s voltage when it is not in use and can provide you with a general idea of the battery’s condition. AGM batteries should have a voltage of approximately 12.2 volts at 50% charge and approximately 12.6 volts at full charge.

A capacity test should be the next examination you conduct. This test gauges the battery’s overall performance while measuring the amount of energy it can store. You’ll need a load tester or a battery analyzer to conduct a capacity test. The battery analyzer measures the voltage and current of the battery while the load tester applies a load to the battery.

A load test is an additional test you can run. In this test, the battery will be loaded, and the voltage will be recorded. You can find out if the battery is capable of delivering power to a load by performing a load test.

The manufacturer’s instructions or a professional should always be consulted if you’re unsure because testing an AGM battery can be a little more difficult than testing a conventional lead-acid battery.

How to Properly Maintain an AGM Battery

To make sure that your AGM battery lasts as long as possible, proper maintenance is essential. Keeping your AGM battery charged is one of the most crucial things you can do to keep it in good condition. When fully charged, AGM batteries should be charged to about 12.6 volts, and when they are half-charged, they should be charged to about 12.2 volts. Additionally, it’s crucial to use a charger made especially for AGM batteries, as using the incorrect charger can harm the battery.

Proper storage is a crucial component of AGM battery maintenance. AGM batteries should be kept out of direct sunlight and kept in a cool, dry location for storage. AGM batteries should also be kept fully charged for storage because storing them discharged can harm the battery.

AGM batteries need to be disposed of properly, it should be noted. They should be recycled instead of being simply thrown away. Many battery recyclers will accept and properly recycle AGM batteries.

How to Fix a Dying Car Battery

It is crucial to have the electrical system inspected and fixed by a professional if you suspect a short circuit. A skilled mechanic will be able to locate the issue and safely fix it.

Once you’ve determined which accessory is to blame for the drain, you can either disconnect it or make it inoperable when the car is not in use. By doing this, battery power will be preserved and the battery won’t run out.

The best course of action is to swap out your old battery for a new one if you think it might be old or worn out. It’s crucial to pick a battery that works with the make and model of your car and to have it installed properly.

It is crucial to have the alternator inspected and repaired by a pro if it is not charging the battery. The battery will typically need to be recharged or replaced, and the alternator will typically need to be replaced as well.

Last but not least, it is crucial to have the alternator belt checked and replaced by a professional if it is slipping or broken. A skilled mechanic can install the new belt correctly and examine the alternator for damage, ensuring that your car runs smoothly and that your battery is charged properly.


Although it can be challenging to determine whether you have an AGM battery or not, they are a fantastic option for a variety of applications. You can make sure that your AGM battery lasts as long as possible by being aware of the key traits of AGM batteries, including how to recognize and test them as well as how to properly maintain them. Keep in mind that AGM batteries cost more than conventional lead-acid batteries, but they have a longer lifespan and perform better when it comes to charging the battery. The alternator will be unable to function properly if the belt slips or is broken.

A dashboard warning light and a squealing or grinding sound when the car is running are signs of a slipping or broken alternator belt, respectively. The alternator may need to be inspected for damage as well as the belt to address this problem. To make sure the belt is installed correctly and prevent further harm to the alternator, it is crucial to have a qualified mechanic inspect and replace it.