Battery capacity and performance. The AGM has more electrolytes because the gelling agent displaces the electrolytes. This give the battery 7%-8% more duration capacity. The AGM also has a lower internal drop that allows a longer run despite a high discharge rate
Elevated temperature. The AGM battery is more efficient in the oxygen recombination cycle that allows it to draw 50% more float current. But the Gel cell is 15% more efficient in heat conduction because the gelled electrolytes are in complete contact with the plates and walls of the container
Float service life. Both the AGM and Gel VRLA batteries have the same 95%-100% capacity