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In the late 1970s, a no water addition lead-acid battery was developed that unlike its predecessor, the Gel battery, used a unique very absorbent separator to hold the battery acid like a sponge. These appropriately named Absorbent Glass Mat Batteries or AGM for short, utilize a non-woven separator made from spun-glass micro fibers and operate on the principle of oxygen recombination; that is, using valves to regulate gassing that turn the oxygen produced by the positive plates of the battery, back into water.

Therefore, oxygen recombination is used to eliminate water addition during the life of the battery. Because these batteries do not “gas freely” they may also be known as Valve Regulated Lead-Acid (VRLA) batteries using AGM technology. As stated, an AGM design uses a non-woven microglass mat separator that is soft, compressible, and very absorbent. In a manner very similar to a disposable baby diaper, the separator absorbs and holds the acid. The separator is 92-96% porous and actually absorbs 7-8 times its weight in acid. The AGM cell is designed so that the thickness of the plates and the AGM separators fit into the cell case very tightly. In fact, most AGM cells are designed in such a way that the AGM separators are ultimately compressed 20-30% when stuffed into the cell case. This gives the cell the needed plate-to-separator interfacial contact and makes this cell very vibration resistant. The highly porous nature of AGM separators leads to lower internal cell resistance and better high rate performance.

In most if not all cases, an AGM battery is a deep cycle battery that can be used in UPS systems, wheel chairs, portable tools, consumer electronics, alarms, boats, heavy equipment and some toys. Other applications can be emergency lighting, telecommunications equipment, backup power systems and solar
powered battery systems.

It must be noted that the process of oxygen recombination lowers negative plate voltage producing smaller amounts of hydrogen gas within the battery. The net result is that AGM cells require a lower charging voltage, and must be charged using a charger specifically designed for this type of battery.

Call your local Powerstride Battery location or shop ONLINE to find the AGM Battery and charger that is right for you!

Powerstride Battery is a global distributor of battery and battery-related products including automotive batteries, commercial batteries, industrial batteries, motorcycle batteries, ATV batteries, marine batteries, telecommunications batteries, and high technology batteries.