Gel cell, AGM and Sealed lead acid are terms commonly and often interchangeably used to refer to the heavy batteries often used in security systems, UPS backup power units, emergency lighting and more.
So if these terms are interchangeably used, are they really the same?
A Gel Cell battery contains acid in a gel form. (No, really!) The acid is ¡®free-floating¡¯ in its container.
Advantages ¨C The gel is not in liquid form so a cracked gel cell does not leak. The gel maintains its ¡®semi-solid¡¯ consistency.
Disadvantages ¨C When over-charged a gel cell battery can develop a ¡®void¡¯ that adheres to the plates in the battery thus reducing the battery¡¯s performance.
AGM stands for Absorbed Glass Mat. This means that the battery contains glass mats that absorb the acid in the battery.
Advantages ¨C More consistency in the operation of the battery. No voids are formed because the voids float to the top and do not adhere to the glass mats.
Disadvantages ¨C When an AGM battery cracks it can sometimes leak a little from the acid that seeps from the glass mats.
SEALED LEAD ACID
A term commonly used to refer to either Gel Cell or AGM batteries. To be a sealed lead acid battery the battery needs to have only two things:
1. It must be a battery that uses acid for electrolytes.
2. It must be sealed
Both AGM and Gel Cell batteries are interchangeable and either can be used to replace the other. AGM batteries are MUCH more common for sealed lead acid (SLA) batteries. Nearly all SLA batteries under 100Ah are AGM.