Well technically what everyone is refering to as a gel battery is actually getting mixed up with a A.G.M. battery. Gel has been superseeded by this new technology. In gel batteries the electrolyte was still free and suspended, in AGM batteries the electrolyte is absorbed into fiberglass cloth inside the battery and stuffed between the plates, so the battery is essentially dry inside, even if you puncture this battery it will not leak. One big advantage is an AGM battery is 80 percent useable amp hours as compared to 50 percent useable in wet cells.