Because lead-acid batteries use sulfuric acid electrolyte, they will leak during transportation, so they need to be sealed. Sealed lead-acid battery thus invented. AGM (Absorbed Glass Mat) and gel batteries are both examples of VRLA (Valve Regulated Lead-Acid) batteries. they're also referred to as SLA (Sealed Lead-Acid) batteries. AGM and gel batteries are often considered to be one because they have a similar core of attributes，both of which are nonspillable.
A gel battery features a similar structure to a standard wet battery. The positive and negative electrodes are surrounded by an electrolyte. However, because the name suggests, the electrolyte isn't in liquid form but rather is within the sort of a gel thanks to the addition of silica. This provides greater resistance to vibration and therefore the inclination of the vehicle. The encapsulated design facilitates handling and improves safety. If the battery is in an intact state, the user doesn't got to be scared of leaking fluid. Therefore, within the trade, gel batteries are often mentioned as maintenance free batteries.
The abbreviation AGM stands for Absorbent Glass Mat. In an AGM battery, the electrolyte is totally bound during a optical fiber mat. AGM batteries are leak-proof and may also affect inclined positions easily . Leak-proofing,position tolerance,greater safety and vibration resistance are positive features of AGM batteries