what is an agm battery

What Is an AGM Battery: The Pros and Cons

Have you ever heard of AGM batteries? Currently, car batteries have outstanding improvements over the old battery lines in terms of reliability, safety, and longer life.

AGM is a new technology battery that are highly appreciated and trusted by many automakers in the past few years. If you are driving a car, but do not know what is an AGM battery? Find out right away through the following article!

What Is An AGM Battery?

When it comes to car batteries, what do you care most about?

We are sure that it’s the battery’s power and quality. However, knowing about the different types can be very important in choosing the right battery to keep your vehicle powered up.

You’re probably familiar with the old-fashioned flooded lead-acid battery, but AGM battery may be a new term for many motorists.

What does AGM battery mean? So let’s make clear the most important things all drivers need to know about the AMG battery. 

At its core, AGM batteries are sealed lead acid type. The internal structure is separated plates made of glass fibers, to increase the permeability of the electrolyte to stimulate the bioelectric chemical reaction.

Therefore, the name AGM also comes from the phrase Absorbent Glass Mat or it also can be referred to as VRLA or SLA. The sulfuric acid in the battery is absorbed by the glass mat.

Hence, they are maintenance-free and spill-proof. As opposed to a standard flooded battery, AGM batteries have twice the capacity of a standard battery and they’re meant for vehicles that need higher power requirements (vehicles that have dash cameras or remote starting systems).

The typical absorption voltage range of this type of battery ranges from 14.4 to 15.0 volts and the typical floating voltage range is from 13.2 to 13.8 volts. Currently, batteries are commonly used for RVs, motorcycle batteries, and generator batteries.

what is an agm battery
Photo: Tashka / Getty Image

Advantages Of An AGM Car Battery

Basically, the operating principle of AGM batteries is the same as other lead batteries. However, when compared to flooded batteries, AGM batteries for RV have been shown to have some significant improvements to make them more efficient:

Spill and leakproof

Spill-proof construction is due to the fact that the electrolyte is held within the mat rather than sloshing around in liquid form. A focal feature of this battery line is the sealed battery technology. Prevent air and liquid from outside from entering and vice versa. Therefore, it can be placed in many directions or moved without worrying about leakage problems like conventional water or MF batteries.

In addition, equipping a VRLA (Valve Regulated Lead Acid) pressure regulator is considered a bright plus when it is possible to adjust the high pressure inside the tank to standard pressure to ensure safe operation.

Provide high power and low internal resistance

Due to AGM’s design, an AGM battery has minimal internal resistance. This, therefore, enables them to provide sufficient power when necessary, such as when drivers start their batteries. Thanks to this feature, these batteries respond better to loading than any other battery on the market.

An AGM battery was proven to deliver more electrical power than EFBs can and recharge up to 5 times faster. AGM batteries meet all requirements for a stable power supply. Fiberglass spacers increase Start-Stop usage by up to 4 times. VRLA-sealed construction increases charging capacity by over 150%. Theoretically, AGM batteries actually dissipate slower than conventional batteries and again they can bounce back from the discharger easier than even a deep cycle.

Special plastic shell material: Optimizing safety, especially in vehicles with batteries in the passenger compartment and seats.

Improved vibration resistance

Vibration resistance due to its sandwich-like construction. Thanks to this special structure that allows AGM to hold up a lot of force and can stand up to weather-related wear and tear. AGM batteries are built up to withstand great vibration, all of that making this type of battery becomes the right choice for heavy machinery. 

Higher cycle life than flooded batteries

AGM batteries are capable of operating for a longer period of time than conventional flooded batteries. This is because these batteries minimize self-discharge, unlike other batteries, which is a big problem. This ensures that one does not have to keep charging them after a long period of inactivity. 

So how long does an AGM battery last? If during operation, the AGM battery is charged properly, not overcharged, an AGM battery can last up to 10 years, it can be much longer compared to other batteries. However, on average, AGM batteries are proven to have a lifespan of three to seven years. Up to 6-10 years extension may be considered if the battery is properly serviced.

Disadvantages Of An AGM Battery

Just like other lead batteries, in addition to many advantages, AGM also has   certain disadvantages:

  • The deep cycle AGM batteries can only be discharged to 50% whereas the lead acid battery can be discharged to 80%. This means that the lead acid battery can run appliances longer on every single charge. Drivers should be careful when charging these batteries as charging too much and too little can affect their lifespan and performance.
  • Another downside of this battery is its price, you will need to pay from $200 to $300 to have an AGM battery. This price is said to be twice as expensive as conventional lead-acid batteries. The price of this type of battery is more expensive than other types because of the high production cost. However, in return, the life of AGM batteries is often much longer than that of lead-acid batteries. Engineered AGM batteries are built to provide up to twice the life of a standard flooded battery. At that time, their disadvantage will become an advantage as you consider the lifespan of this battery.
  • Although the output power is quite high, the specific energy of the AGM battery is a bit low. If your car is using AGM batteries for a long time, we’re sure you also know that AGM batteries can only be used under moderate loads to reach high specific loads. As a result, your vehicle may not be able to power some devices that use AGM batteries.

AGM Battery vs Gel Battery: What Are The Differences? 

Many drivers reckon mistakenly that  AGM batteries and Gel batteries are the same. Although both types of batteries possess similar characteristics such as spill-proof construction and can be used in different orientations. However, these two types of batteries are completely different:

  • As we know, AGM batteries use a special glass mat made up of thin glass fibers to absorb the electrolyte between the battery panels. On the other hand, Gel batteries use silica gel to hold electrolytes together. Electrons can freely move between the plates thanks to the thick consistency of the material.
  • Gel batteries can lose energy faster than AGM batteries at lower temperatures due to the battery’s Thixotropic gel composition. Because AGMs can operate in extreme weather conditions, they are better able to maintain power.
  • In contrast, Gel batteries can use acid better than AGM batteries when talking about the depth of discharge (DoD). Acids help protect the ranges of the gels which enhances their deep flushing applications.
  • Compared to Gel batteries, the price of AGM batteries can be cheaper comparably. However, this type of battery has a longer life than a Gel battery and provides bigger bursts of the amp when your vehicle needs it.  
  • If kept in a charged state when unused, the common 12-volt AGM or Gel batteries can last up to 6 years. After 5 or 6 years of float voltage at an average ambient temperature of 25°C. These batteries still retain 80% of their original capacity. 

In Conclusion

AGM batteries are available to handle today’s power demands. They provide the ultimate combination of reliability, durability, and safety. We can’t deny the benefits that this type of battery can offer. AGM batteries are non-spillable, vibration resistant, and meet the most stringent OE requirements.

We hope that the information we provide above will help you have an overview of this type of battery. And help you make the right decision when buying an AGM battery for your car.

*Featured Photo by Tashka / Getty Image

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  1. Dan

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