If your charger/maintainer does not keep the battery at 12.7 volts minimum, then can it.
There are several stages of charging.
My manual process(winter) is to charge a battery at 14.4 volts for a day, repeat a month later.
Sulfation, Undercharging, and Battery Failure
The leading cause of battery failure is sulfation. Sulfation is a deposit of lead
sulfate crystals on the charging plates that resists the battery’s ability to accept a charge.
Eventually, the deposits will prohibit charging, reducing both the
battery’s capacity and functional life. The source of the sulfate is the water and
sulfuric acid electrolyte solution inside the battery. An ongoing electrochemical
reaction between opposite charges occurs in the electrolyte solution that produces electrons.
These reactions are at their optimal state while the battery is at
the correct full charge, but are diminished when the battery is undercharged or overcharged.
During normal charge and discharge some minor sulfation occurs, but major sulfation
can develop when the battery is stored in an uncharged or undercharged
condition, which eventually slows and stops the electrochemical reactions. If these
reactions stop, sulfation is accelerated as the sulfur leaches out of the electrolyte
solution and attaches itself to the lead charging plates. As more crystals deposit on
the charging plate, the ability for the battery to accept full charge diminishes, and
undercharging worsens. This is a downward spiral to premature battery failure.
Two common maintenance practices that contribute to
sulfation are storing batteries in an uncharged condition and undercharging.
Both of these conditions can be prevented by using smart charging technology to safely
maintain stored batteries at full charge.