Wet cells (submerged), sealed gel batteries, and absorbed glass mats (AGM) are various versions of lead-acid batteries. Wet cells come in two styles; serviceable and maintenance-free. Both are full of electrolytes, basically the same.
Sealed gel batteries and AGM batteries are specialty batteries that typically cost twice as much as premium wet batteries. However, they store well and do not sulfate or degrade as easily as wet batteries. While not impossible, there is a small chance of hydrogen explosion or corrosion when using these batteries; they are the safest lead-acid batteries you can use.
AGM Batteries: Absorbent glass mat structure allows liquid electrolytes to be suspended in the fiberglass mat. The mat surrounds the active material of the plates, which in theory could improve discharge and charge efficiency. AGMs are commonly used in high-performance engine starting, power sports equipment, deep cycle, solar, and battery applications. The larger deep-cycle AGM batteries we sell typically offer a very long cycle life if they are charged before dropping below the 50% discharge rate. When a deep cycle AGM battery is discharged to a rate of not less than 60%, the cycle life will generally increase by 300+ cycles.
GEL: Gel batteries, like AGM batteries, are considered non-spillable, but the electrolyte is not a wet liquid. The electrolytes in gel batteries contain silica additives that cause them to solidify or harden. In most cases, gel batteries are usually charged at a lower voltage than standard submerged wet cells or AGM batteries, whose 12-volt cells can accept up to 14.6 volts. Most gel batteries can only charge up to 14.2 volts per 12-volt battery and are probably the most sensitive batteries in terms of adverse reactions to over-voltage charging. Gel batteries are best used in very deep cycle applications and may last longer in hot weather applications or applications where the battery is over-discharged. If an incorrect battery charger is used on a gel battery, poor performance and premature failure are certain.
Changshu Wanlong Power Technology R&D Co., Ltd. is a lead-acid battery manufacturer and storage battery manufacturer from China. The company sells sealed maintenance-Free batteries and Sealed 12v batteries all year round.