How do I know if my Battery is AGM 2024

Have you been using your car for a while, yet you don’t know what type of battery it operates, and you have been wondering, “How do I know if my battery is AGM?”

Absorbed Glass Mat (AGM) batteries are a unique battery type that contains a special glass mat separator that helps to wick the electrolyte solution between the battery plates.

It works by letting the electrolyte pass through the fiberglass mat, thereby creating a maximum surface area to touch the plates and not flood the battery with so much fluid.

Some of the essential characteristics of AGM batteries include the following; AGM batteries are sealed; hence, they do not spill, are resistant to vibrations, are maintenance-free, offer minimal acid leakage and gassing, and provide better cycling performance.

What is the difference between Gel, AGM, or Standard Batteries?

Knowing your car’s battery type is essential so that you can understand all that is required in carefully handling the battery.

A simple mistake can affect a battery, thereby shortening the battery life or harming the user.

As battery technologies continue to evolve, AGM batteries are the newest type of batteries, and there are slight differences between them and other conventional batteries.

It is pretty easy to tell the difference between Gel, AGM, or Standard batteries. Some of the differences are as follows.


One of the main ways to differentiate between Gel, AGM, or Standard batteries is to check the label on top of the batteries. Gel-filled lead-acid batteries have the inscription “Gel-Filled” on the battery label.

Meanwhile, AGM batteries have any of the following inscriptions on their label, “Absorbed Glass Mat,” or “AGM,” “dry cell,” “valve regulated,” “sealed regulated valve,” or “non-spillable.”

Flooded or liquid lead-acid batteries have the inscription “wet cell,” “lead-acid,” “liquid lead-acid,” or “flooded lead acid” on their labels.

Endeavor to check your vehicle’s battery to see the inscription on the label on top of the battery. If it’s AGM, it should have at least one of the short inscriptions outlined for AGM batteries above.

Otherwise, it is some other battery; however, the inscription on the battery label will reveal the kind of battery in your car.

Battery top structure

AGM batteries and Gel-filled lead-acid batteries both have flat tops except for the positive and negative terminals on the tops.

Flooded or wet cell batteries have removable tops or caps, except they say “Sealed” on the battery’s label.

Response to shaking

Another way to differentiate between Gel, AGM, or Standard batteries is to observe the battery response when you shake them.

Liquid acid or flooded batteries wiggle when you shake them and later hold them still; that is, you will notice an extra movement in the battery’s liquid center for a moment, irrespective of whether it is sealed.

An acid battery is dangerous because of this setback; hence, you must be careful if your car uses an acid battery type.

Meanwhile, an AGM or a gel battery does not wiggle when you hold them still after shaking them. They remain the way they were before the shake.

Those are some fundamental differences between Gel, AGM, and Standard batteries.

It is essential to be careful with flooded batteries because their acid can burn human tissue if there is established contact. They can produce chlorine gas if they come in contact with seawater.

Meanwhile, AGM and Gel cell batteries can be damaged easily or quickly if the charging current is higher than necessary. Therefore, it is vital to know the kind of battery in your car and what to do to ensure that the battery is kept safe and you do not endanger yourself.

Related Topic: How to charge a battery without a charger

Some FAQs

Are new AGM batteries fully charged?

No, new AGM batteries are not fully charged; hence they need to be fully charged before use. A new AGM battery is about 75 to 80% charged.

Therefore, to start using a new AGM battery, you need to fully charge the battery using a charger with a charge rate of 12.8+ volts. It would be best if you avoided a battery charging current level that is more than 32.72 degrees Fahrenheit in other not to experience a premature failure in the battery.

While charging the new AGM battery, the voltage may go beyond 16 volts; hence, you should check the open circuit voltage after about 1 to 2 hours. Meanwhile, manufacturers recommend that AGM batteries be charged for not less than 5 hours. Also, avoid charging for extended periods.

Can you use a regular charger on an AGM battery?

Have you ever been told that you can use a regular charger on an AGM battery? That recommendation is false, as you are not expected to use a normal charger on an AGM battery.

AGM batteries are designed to be charged slowly and low; hence, AGM battery chargers are designed with microprocessors responsible for the collection of information from the battery and the appropriate adjustment of voltage and current.

What is the best charger for AGM batteries?

Since AGM batteries have a chemical structure without electrolytes of a liquid type like lead-acid batteries, they are designed to accommodate slow and low charge; they require special chargers.

The recommended chargers are equipped with a unique microprocessor that helps collect information about the battery’s power elements and make necessary adjustments on the current and voltage to the battery specifications.

Some of the best Absorbed Glass Mat battery chargers are;

  • [amazon link=”B07W3QT226″ title=”NOCO Genius 10″]
  • [amazon link=”B07W8KJH44″ title=”NOCO Genius 5″]
  • [amazon link=”B07W3QSMF9″ title=”NOCO Genius 2D”]
  • [amazon link=”B000FRLO9Y” title=”CTEK (56-353) MULTI US 7002″]
  • [amazon link=”B000CITK8S” title=”Battery Tender Junior 12V 0.75A Smart Battery Charger and Maintainer”]
  • [amazon link=”B00DHGPVKI” title=”Optima Digital 400 12V Performance Maintainer and Battery Charger”]
  • [amazon link=”B01D3SWXUA” title=”BatteryMINDer 128CEC1″]
  • and [amazon link=”B07BLLRM8R” title=”‎Schumacher SC1281″]

You can take some time to find out the reviews about them.

How can you tell the difference between AGM and flooded batteries?

Although Absorbed Glass Mat (AGM) batteries or dry cell batteries and flooded or wet cell batteries are together considered lead batteries, they also have areas of difference. 

The difference between AGM and flooded batteries can be seen in how they work, as well as their pros and cons.

AGM batteries are maintenance-free, and they contain a unique glass mat separator that helps to saturate the fiberglass with electrolyte and stores the electrolyte in a suspended or “dry” state instead of in liquid form.

AGM batteries do not require watering service; also, they perform better than wet cell or flooded batteries since there is no minimal gassing and free liquid.

However, they can be damaged if undercharged or overcharged over some time.

On the other hand, flooded batteries contain a liquid electrolyte combination, and the liquid is expected to be carefully measured and maintained for the battery to work efficiently.

Flooded batteries are more cost-effective than AGM batteries. However, extreme climates can adversely affect the battery life because of the electrolyte solution in the battery, which can either freeze or evaporate.

Final thoughts

If you were thinking, “How do I know if my battery is AGM?”

Remember that one of the simplest ways to know if your battery is AGM is to look at the battery top; you will find one of these inscriptions on the battery label on top of the battery, “Absorbed Glass Mat,” or “AGM,” “dry cell,” “valve regulated,” “sealed regulated valve,” or “non-spillable.”

Since there are various types of batteries and battery styles, ensure to find out the kind of battery your car uses.

Also, endeavor to understand all that it entails; maintaining the battery for efficient performance so that the battery can both work well and not endanger your car’s components.


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