This is probably the fourth time I've seen the AGM battery mentioned on this site. What's up with that?
It's a battery type, the construction and materials. A
Costs a bit more than a wet cell, but well worth every penny and a $5 tip.
Many reasons they are better... won't vent acid into the R/R and connector. Holds charge better and delivers more voltage, less affected by cold. Most of us believe the VN starts better with one, they are definitely sensitive to low cranking volts, which affects the IC Ignitor. (engine backfires, won't start)
Wet Cell/Lead Acid
The underlying fault with all lead acid batteries is the requirement for an excessively long charge time arising from a two-stage process: bulk charge and float charge. All lead acid batteries, irrespective of type, are quick to charge to 70% of capacity within 2 or 3 hours, but require another 9 to 10 hours to "float charge" after the initial charge. If users fail to float charge, battery capacity is dramatically reduced. All types of batteries have a "memory" in that every time a user charges to less than 100% charge, battery capacity is shortened. A lead acid battery could reach 4,600 cycles if it were kept on a shelf and kept at the right state of charge.
Because of calcium added to its plates to reduce water loss, a sealed AGM battery recharges more quickly than a flooded lead acid battery of either VRLA or conventional design. "From a standard car alternator they will recharge quickly from full use in about 2 to 3 hours. A deep cycle wet cell battery can take 8-12 hours to achieve only 70% to 80% of its potential charge. (charge rate for car battery)
AGM & Gel VRLA batteries:
Have shorter recharge time than flooded lead-acid.
Cannot tolerate overcharging: overcharging leads to premature failure.
Have shorter useful life, compared to properly maintained wet-cell battery. (disagree here).
Discharge significantly less hydrogen gas. (and acid)
AGM batteries are by nature, safer for the environment, and safer to use.
Can be used or positioned in any orientation.