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Battery System

How Do I Know if My Battery Is AGM? – 3 Foolproof Ways!

How Do I Know if My Battery Is AGM
Last Updated on Aug 16, 2023 By Paul Lucas

Owning a car comes with its fair share of pitfalls, including the burden of maintenance. As such, any driver worth their while must pay close attention to the different components of their car and, most importantly, the battery.

Many drivers hardly know much about their car’s battery and it’s not surprising that so many wonder if their batteries are AGM?” is common among car owners.

What does AGM mean on a battery?

AGM is an acronym for Absorbed Glass Mat. Unlike the conventional batteries, AGM batteries are built differently because they come with a glass mat separator that helps cushion the lead plates from friction. Often, too much friction reduces the battery life.

How Do I Know if My Battery Is AGM?

  • Reading the label

As with any other type of battery, it is essential to study the labels. Often, the tags will furnish the buyer with different kinds of information, such as whether the battery is sealed or standard. Besides, the labels on AGM batteries will state something like “Absorbed Glass Mat” or “AGM.”

  • Observing the battery’s top

The removable caps of AGM batteries have the word “sealed” written on them. In addition, the flat tops of these batteries have negative and positive endpoints sticking out.

  • Shaking the battery

One of the stand-out features of AGM batteries is that there’s no chance of acid spillage. As such, it is possible to check the battery’s authenticity just by shaking it. When shaking the battery, it is important to observe whether there is any liquid jiggling inside it.

Advantages of AGM batteries

  • Spill-proof

AGM batteries are spill-proof; thus, they do not flood their electrodes. These batteries come with glass mats, so they can easily prevent the electrolyte from spilling over.

  • Reduced charging time

AGM batteries have a short charging time in comparison to flooded batteries. In fact, the charging rate of AGM batteries is five times faster than that of traditional lead-acid batteries.

  • Longer lifespan

Unlike other batteries, AGM batteries can be used for a more extended period because they have a longer lifespan. Whether or not they are in active use, AGM batteries are bound to last longer because they hardly lose charge.

Disadvantages of AGM batteries

  • Energy issues

AGM batteries have been singled out for low specific energy, making it impossible to use them on several devices.

  • High production cost

While these batteries have become a market favorite, they have a high production cost. In any case, manufacturers have done everything possible to reduce the cost of production, but it is still generally high than that of other battery types.

  • Low tolerance to overcharging

AGM batteries do not augur well with overcharging and high voltages. Therefore, if these batteries are continuously exposed to these conditions, they will likely reduce their lifespan.

Uses of AGM batteries

Given that AGM batteries have a sturdy design, they are the most preferred option in military and commercial aircraft. After all, these batteries are not vulnerable to wear and tear that may be occasioned by frequent vibrations in a plane.

These batteries also convert chemical energy to electrical energy in high-end motorcycles and race cars.

How Do I Change AGM Batteries?

When the time to change AGM batteries beckons, it is important to seek professional help. After all, changing AGM batteries has become a complex feat. These days, more and more car manufacturers are moving batteries away from the engine compartment. Some of these batteries have been moved to the trunk, whereas others have been placed in the passenger compartment.

The complexity of accessing these cars’ batteries demonstrates why it is essential to enlist professional services.

Car owners should take extra care when replacing their AGM batteries because any wrong move can result in severe malfunctions. For instance, incorrect replacement can affect the start-stop function, leading to increased fuel consumption.

Changing an AGM battery that has not been placed in the engine compartment can take up to 28 steps. As a result, drivers are better off when they seek the input of experts accustomed to modern-day battery technology.

Are AGM batteries worth it?

Going by the benefits derived from AGM batteries, a car owner stands to get value for money spent. In any case, these batters are durable, and they produce a lot of power.

When kept in good condition, AGM batteries are easy to maintain. These batteries are designed in such a way that they can serve different functions, such as off-grid living, RVing, and boating.

Yes, they are worth the investment because they can be recharged and discharged many times. Besides, AGM batteries hold their charge for prolonged periods than lead-acid batteries.


1. How many years do AGM batteries last?

Ans. An AGM battery’s expected lifespan is between three and four years. However, this lifespan is dependent on whether the battery has been properly maintained. Also, the distance travelled will determine how long the battery will last.

If it’s an electric car, the battery will need to be replaced more often than that of other vehicles. When these batteries are used in electric cars, they’re prone to wear and tear.

2. Why should I replace my current battery with an AGM battery?

Ans. By replacing your battery with an AGM battery, you will derive various benefits. For starters, AGM batteries have a longer lifespan. Also, this battery can power your car more than 60,000 times. An AGM battery is vibration and shock resistant, and this helps to reduce wear and tear. Unlike your current battery, an AGM battery has a higher power output due to low internal resistance.

3. Is AGM better than gel battery?

Ans. When faced with a choice of choosing between AGM battery and gel battery, the former carries the day. While these batteries have similar traits, AGM batteries outdo gel batteries on various fronts, such as charging, durability, and lifespan. Besides, AGM batteries are less expensive, and they’re tolerant to different weather conditions.

About the author

Paul Lucas

I grew up in a classic car-oriented family, and was taught how to differentiate between a Ford and a Chevy by my dad when I was just five years old! With special feelings for anything Italian, I enjoy driving and restoring old cars.

Over the years, I became tired of those cookie-cutter auto blogs that copy content from each other and decided to take matters into my own hands! So, I am here to bring you the latest auto industry news, tech innovations, the hottest cars and their specs, reviews, test drives, tuning, and more.

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