Don for crying out loud, get your hands on an infrared thermometer (thermocouple) then charge your batteries at the same rate as everyone else with the same type of battery. Monitor for thermal buildup. Not just the top of the case, but the lead terminals. Improperly high charging rates WILL raise cell temperature and will raise terminal temperature. If it doesn't increase disproportionately with applied amperage, then common sense should tell you the battery is not undergoing damaging superamperage.
"Sir, why did you wait at this red light for forty-eight minutes?"
"Uhhh, it didn't change. Ya telling me I should run a red light?"
Good batteries, that use H2SO4 will gain temperature when a lot of amperage is put through them. If there is little or no temperature gain (using a RATIONAL value of amperage) then that charging rate is not inappropriate.
This doesn't mean 2,000 amps for ten seconds. Please no word games. The manufacturers of these items are after one thing, and one thing only - absolute positive maximum battery life despite "The Cost". Try 110% "recommended charge maximum to start off with. Your thermocouple will not lie to you.
