Absorbed Glass Mat (AGM) batteries are the newest type of dry lead-acid batteries. These batteries are used as a replacement for wet-cell batteries.
Lead-Acid batteries are commonly used in motor vehicles and power grids. They have a wide application, mainly in cars and boats. Depending on their construction, these batteries can be divided into Liquid Lead-Acid, Gel, and AGM batteries.
AGM batteries are a type of Valve Regulated Lead-Acid batteries. They are much safer and more durable than their liquid and gel battery counterparts.
Charging them is also easier and faster. Moreover, they have an extended cycle life as well. They are resistant to vibrations and are easier to mount, making them a better choice than Wet-Cell and Gel Lead-Acid batteries.
There are two methods to determine if you have an AGM battery.
Method 1: Determine the type of battery by reading the label
Look for the label that reads ‘AGM’ or ‘Absorbed Glass Mat.’ Moreover, the tags ‘Dry Cell’, ‘Sealed Regulated Valve,’ or ‘Regulated Valve’ also indicates that the battery is an AGM battery.
On the other hand, liquid batteries and flood-cell batteries have labels that include ‘wet cell,’ ‘lead-acid,’ or ‘flooded lead-acid.’ In addition, some liquid batteries also have labels that state ‘liquid lead-acid’. Make sure to avoid these tags if you are looking for an AGM battery!
Method 2: Look at the crest of the battery
AGM batteries have a flat top and are sealed. Arising from this flat top are the positive and negative endpoints. Take the battery in your hand and give it a good shake. If you have an AGM battery, you will not feel any movement inside the battery.
In contrast, liquid lead-acid batteries have a liquid center. Upon shaking, the insides will move about, even if it is sealed. Moreover, you will continue to feel this movement for some time. Liquid lead-acid batteries have caps and removable tops, unlike the sealed top of AGM batteries.
If you do employ this method, make sure to use safety goggles and rubber gloves. Wet-cell batteries have acid inside them. Furthermore, they have removable tops which can easily come loose. The acid is harmful and can burn through human tissue. Additionally, if it comes in contact with seawater, it can produce toxic chlorine gas.
How to Tell if a Battery is Sealed or Standard?
Rechargeable Lead-Acid batteries can also be divided into two broad types based on their construction. Standard and Sealed Batteries are very popular and commonly used in motor vehicles and power supply grids.
Sealed Rechargeable Batteries
As the name suggests, these batteries have a sealed construction. They are used in power systems, namely Solar and Wind Power systems. In addition, they are also used in motorcycles and All-Terrain Vehicles (ATVs).
Identifying a Sealed Rechargeable Battery is similar to how you would determine if you have an AGM battery. The easiest method to figure out the type of battery is by reading the label that comes with the battery. Sealed batteries have the word ‘Sealed’ written on their labels.
Another method is to study the top of the battery. These batteries have a sealed construction. As a result, you will notice that these batteries have a flat top, except for the places where the positive and negative terminals protrude. Moreover, they do not have any vents or caps.
If you still haven’t figured out the type of battery from the above methods, you can try shaking the battery. Unfortunately, the inside of these batteries does not show any movement, no matter how hard you shake it!
Sealed Rechargeable Batteries come in two types, the Gel and Absorbed Glass Mat (AGM) types.
Standard Rechargeable Batteries/ Flooded Rechargeable Batteries
Also known as Flooded Rechargeable Batteries or Wet-Cell Batteries, Standard Rechargeable Batteries are more commonly used. They are the industry standard when it comes to application in reserve power systems. In fact, these batteries are widely used in power, utility, and grid energy storage systems.
You can always look at the battery label to find out if you have a Flooded Rechargeable Battery. The label on these batteries usually read ‘lead-acid,’ ‘wet-cell, or ‘liquid lead acid.’ If you cannot find the level, you can look at the crest of the battery. Also, these batteries have a removable top case so that you can easily add water periodically.
The last method you can employ is giving your battery a good jiggle. If you hear or feel the insides move, it is a standard rechargeable battery. However, take care while doing so as the top cover may come loose. In addition, these batteries contain corrosive acids, which can damage your skin tissues.
Standard Rechargeable Batteries usually contain a liquid combination of acid and water, wherein the most commonly used one is Sulfuric Acid. Other types of Wet-Cell Batteries use stronger acids.