I don't constantly charge it. I only charge it when the Astron RS-20 is turned on and 13.8 vdc will not overcharge a 12v lead-acid battery. Your attempt at a strawman is noted. I don't count the cycles. My deep discharge marine batteries die of old age after far outliving their warranties. (P.S. I'm a EE and have been a ham for 55 years. As a SCADA engineer, I am familiar with battery backup systems.) Sorry to disappoint you but here's a photograph of the battery. Enlarge it and you will find "Trolling, Starting, Deep Cycle, RV, and marine." It is a 125 AH battery.