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Can You Desulfate an AGM Battery -Exploring the Possibility

Can You Desulfate an AGM Battery
Can You Desulfate an AGM Battery

When it comes to deep-cycle batteries, sulfation is one of the major problems caused by negative chemical reactions. This issue is mostly seen in conventional lead-acid batteries where the cathode causes sulfation. However, Absorbed Glass Mat (AGM) batteries have been engineered with new and advanced technologies. The electrodes in AGM batteries are made with thin lead plates placed in a confined and compact manner. This is why the sulfation rate is lower in AGM batteries than in other batteries. One question that arises is, can you desulfate an AGM battery.

The positive news is that AGM batteries can easily be desulfated by following orders to remove the sulfation. This article will provide you with all the necessary information on how to effectively desulfate AGM batteries.

What Exactly Does Desulfation Mean for AGM Batteries?

AGM batteries are a type of deep cycle battery that operates on the principle of an oxidation-reduction reaction. The battery consists of two electrodes and an electrolyte, which is typically dilute sulfuric acid. During the battery’s operation, the electrolyte breaks down into sulfate and hydrogen ions.

Over time, the negative electrode in the battery can accumulate a layer of lead sulfate crystals due to voltage fluctuations and chemical reactions. This process is known as sulfation, and it can reduce the effectiveness of the electrodes and decrease the battery’s power production.

Desulfation is the process of reversing sulfation by breaking down the lead sulfate crystals into ionic forms. This process helps to maintain the balance of ions in the electrolyte and improve the overall health of the battery. AGM batteries can be desulfated using a compatible battery charger or desulfator, which is a smart device that automatically detects the sulfation rate in the battery and removes it by choosing the best suitable desulfation profile.

Is it Necessary to Desulfate an AGM Battery?

Sulfation is a common phenomenon that can occur in most lead-acid batteries, including AGM batteries. Over time, sulfation can degrade the battery’s health and cause it to discharge more often than normal. This can affect the overall battery performance and longevity. Therefore, it is necessary to desulfate an AGM battery from time to time to keep the state of charge optimum and prevent degradation of the battery’s health.

Desulfation Keeps Your Battery Health Optimum

Sulfation in the AGM battery can slowly degrade the battery’s health and discharge it more often than normal. The depth of discharge of the AGM battery is only 50%, and a highly discharged battery can affect the overall battery performance and longevity. Therefore, the AGM battery is sensitive to over-sulfation, which can reduce the battery’s health and cause it to die slowly. Regular desulfation of the AGM battery can prevent all these issues and extend the battery life more than the expected time.

Improves the Power Delivery

Desulfation in your AGM battery prevents the flow of current, which inhibits the electrode from reacting further with the electrolyte. This ultimately degrades the power delivery of the battery. Highly sulfated batteries cannot produce sufficient cranking amps, which can affect the proper functioning of electronic appliances or a car. Therefore, regular desulfation of the battery is mandatory to prevent the battery from becoming dull and to increase the overall power delivery.

Desulfation Enhances the Charge Holding Capacity

Sulfation significantly reduces the charge holding capacity of the AGM battery. No matter how much you recharge your battery, it cannot hold the state of charge for a long time. Regular desulfation of the battery removes all the unusable crystals back into the electrolyte, which lets the battery hold more charge. This way, you can increase your battery’s state of charge to a stable condition by desulfating the battery on a regular basis.

Increases the Longevity of the AGM Battery

Heavy sulfation can lead the battery to get deeply discharged if left untreated for a long time. This can affect the longevity of the battery, which has an average life expectancy of 3-4 years. Regular desulfation of the battery can improve its longevity by maintaining the balance of the charges in the electrolyte and increasing the reactivity of the lead plates.



Is it possible for you to Desulfate an AGM battery?

AGM batteries Are Lead-acid battery

AGM batteries are a type of advanced lead-acid battery. The difference between an AGM battery and a conventional lead-acid battery lies in the construction of the AGM battery cells. AGM batteries have compressed cells, where the AGM separator is absorbed with sulfuric acid and sandwiched between the plates. This means that there is no free liquid form of electrolyte in the AGM battery, unlike the standard batteries that have liquid electrolytes and thick electrode plates directly suspended in the electrolyte. As a result, sulfation occurs less often in AGM batteries than in lead-acid batteries.

AGM batteries Have a Lower Sulfation Rate

Compared to flooded wet-cell batteries, AGM batteries have a lower rate of sulfation. Although AGM batteries are quite sensitive to overcharging, they can still be desulfated using basic methods such as other battery varieties.

You can desulfate an AGM battery using multiple ways

Desulfation of an AGM battery can be done in many ways. The best way to desulfate an AGM battery is to use a suitable smart desulfator device or automated battery chargers. Dedicated desulfating devices are also available in the market that specializes in AGM batteries. All these options give enormous opportunities to desulfate an AGM battery.

Desulfation is an Easy Process

Desulfation of AGM batteries is an easy process that does not require an expert or professional help. You can do it by yourself in your garage. All you need is the specified smart charger for your AGM battery. Compared to lead-acid battery sulfation, AGM batteries take less time to desulfate.

Can You Desulfate an AGM Battery – When Do You Need To?

AGM batteries can provide satisfactory service for a long time, but sulfation can affect their overall performance. Here are some signs that indicate you need to desulfate your AGM battery:

  • Slow cranking: If your AGM battery fails to provide the expected cranking amps to your vehicle’s engine, sulfation may be the culprit. Desulfation can help produce the heavy amp-hours (Ah) required to ignite the engine.
  • State of charge: You can use a voltmeter to check the consistency of the state of charge of the AGM battery. If the battery cannot retain the charger status for a long time without being connected, it may require desulfation.
  • Reserve capacity: After getting deeply discharged, if your battery fails to hold the charger consistently, it may require desulfation. Deeply discharging the battery energizes the sulfation process because the specific gravity of the electrolyte falls below 1.227.
  • Fully charged battery: If the battery cannot hold the voltage even after being completely charged, sulfation may be the culprit. If the battery has not crossed the warranty limit, desulfation can be considered.

Apart from these signs, the desulfator and the battery charger can show you the sulfation status of the battery.

It is important to desulfate your AGM battery as soon as possible to restore its performance. In the next section, we will discuss the process of desulfating an AGM battery.



How Can You Desulfate an AGM Battery?

AGM batteries are prone to sulfation and require maintenance to keep them in good working condition. In this section, we will discuss the most effective methods for desulfating AGM batteries.

Desulfation Mode

One of the easiest and most effective ways to desulfate an AGM battery is to use the desulfation mode on a fully automated battery maintenance device. These devices are equipped with digital displays that show all the battery parameters and status, making it easy to diagnose and select the appropriate desulfation mode and time. Here are the steps to follow:

  1. Disconnect all cables and appliances from the AGM battery.
  2. If the battery is installed in a vehicle, unscrew the safety frame and remove the battery.
  3. Keep the battery in a shady, well-ventilated area.
  4. Connect the battery maintainer to a 120V wall socket.
  5. Clean the battery terminals using steel wool to remove any corrosion.
  6. Connect the cables from the device to the battery carefully.
  7. Select the correct desulfation mode and time and switch on the device.
  8. Keep a voltmeter connected to the battery to prevent overvoltage attacks.
  9. Allow the process to complete in 2-3 hours.

Recharging the AGM battery slowly

Recharging the AGM battery slowly is another effective way to desulfate it. This process involves pushing consistent voltage and low amperage to break down the sulfation products. Here’s how to do it:

  1. Remove all connectivities and keep the battery isolated.
  2. Ensure the charging area has good airflow.
  3. Connect the battery charger to a wall socket.
  4. Turn on the charger and connect the cables with the battery terminals carefully.
  5. Select the charging profile for the AGM battery.
  6. Keep the voltage input to 20V and amperage input to 2-5 amps.
  7. Attach a spare voltmeter to track the real-time voltage of the battery to prevent overcharging.
  8. Start the charging process. It may take 5-6 hours to complete full charging of the battery. Check the state of charge of the battery from time to time.

Trickle Charging

Trickle charging is a slow charging method that can effectively desulfate an AGM battery. This method is particularly effective for highly sulfated batteries. Here are the steps to follow:

  1. Disconnect all electronic appliances from the battery.
  2. Store the battery in a shady and windy space.
  3. Clean the terminals from corrosion.
  4. Connect the regular AGM charger with the battery and connect the charger to a 120V wall socket.
  5. Select the trickle charging option from your smart charger and lower the voltage input if possible.
  6. Start the charging process.
  7. Connect a multimeter for supervising the voltage of the battery.
  8. The desulfation procedure may take 24-48 hours to complete using this method.


Can You Desulfate an AGM Battery

How much time does it need to desulfate an AGM battery?

The time required to desulfate an AGM battery depends upon the level of sulfation and the state of charge of the battery. Slightly sulfated AGM batteries can be desulfated in 2-3 hours using the dedicated desulfation modes available in battery maintainers. However, highly sulfated batteries may take up to 24-36 hours or more to complete the desulfation process. Deeply discharged batteries may even take up to 48 hours for desulfation.

It is worth noting that the desulfation process should be performed quickly, as lead-sulfate crystals can form a hard and permanent layer on the electrode, which can reduce the battery life and charge holding capacity.



Can You Desulfate an AGM Battery FAQs

How to rejuvenate an AGM battery?

To rejuvenate an AGM battery, you can use the jump-starting process. For this, you need a good AGM battery connected to the dead battery in parallel. The high amperage of the fast charging profile is exerted on the good battery. This shall jumpstart the dead battery and increase its voltage slowly. After several hours, by regular charging, the dead battery can be revived.

How to clean an AGM battery?

An AGM battery is a maintenance-free and completely sealed battery. You can keep the terminals of the battery cleaned of the corrosion by regular scrubbing using the steel wool. Besides, there are some valves for maintaining the internal pressure. These valves should be cleaned using soft buds and soft clothes.

Will a trickle charger desulfate a battery?

Yes, trickle charging is an effective way to desulfate a battery. It works better on deeply discharged batteries. But, trickle charging a battery can take up to 48 hours of time to complete the process.

Will a sulfated battery hold a charge?

No, a sulfated battery cannot hold charge like the original state. The sulfated battery cannot be returned to the original state by 100%. So the holding capacity of the sulfated battery is very minimal compared to the desulfated battery.

How to know if a battery is sulfated?

A sulfated battery cannot charge for a long time. It shows reduced voltage output in the voltmeter or multimeter. Besides, the power output is not sufficient. The Amp-hour, cranking amp, and the reserve capacity of the battery get reduced if the battery is sulfated.

Using these signs, you can detect the sulfated battery. Moreover, the sulfate detection option in the smart battery maintainer shows you the status of the battery sulfation.

How to fix a sulfated battery?

Fixing a sulfation battery can be done by using a battery maintainer. These devices have a dedicated desulfation method. Besides, the battery chargers are cheap. These can be used to remove the sulfation in the battery.

Can AGM batteries become sulfated?

Yes, AGM batteries can become sulfated over time. Sulfation occurs when lead sulfate crystals build upon the battery’s lead plates, which decreases the battery’s capacity and performance.

How do you reverse AGM battery sulfation?

To reverse AGM battery sulfation, you can use a desulfator or a compatible battery charger. Desulfation mode is a common feature found in some battery chargers. Additionally, you can use desulfating agents and additives to help break down the lead sulfate crystals.

How to desulfate a deep cycle battery?

To desulfate a deep cycle battery, you can use a compatible battery charger or desulfator. It is important to note that the desulfation process can take several hours or even days, depending on the battery’s level of sulfation.

What is desulfation mode?

Desulfation mode is a feature found in some battery chargers, which sends high-frequency pulses of energy to the battery to help break down the lead sulfate crystals. This mode can help reverse sulfation and extend the battery’s lifespan.

Do Desulfators work on AGM batteries?

Yes, desulfators can work on AGM batteries. However, it is important to use a desulfator specifically designed for AGM batteries to avoid damaging the battery.

How do I know if my AGM battery is sulfated?

You can perform a battery load test to determine if your AGM battery is sulfated. A sulfated battery will have a lower capacity and performance than a healthy battery. Additionally, you may notice that the battery takes longer to charge and has a shorter lifespan.

Can You Desulfate an AGM Battery – Wrapping Up

In conclusion, sulfation in the lead-acid batteries degrades the battery performance. With a lack of inspection, the battery loses its longevity due to the need for desulfation. Storing the battery in a discharged way contributes to the sulfation process. That is why you have to keep a keen eye on the performance of your AGM battery.

Since an AGM battery is also a lead-acid battery, sulfation occurs here as well. The question of can you desulfate an AGM battery can be answered as Yes, you can. To keep your battery healthy and increase the lifespan, you have to have regular inspection.

And, when needed you must recharge the battery followed by desulfating the battery. Doing this on a routine basis will keep your AGM battery safe from desulfation.

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