Dan and Ted are right. "Sulfation" is a problem IF you leave your battery in a deeply discharged state or you discharge it fully against a load. However "sulfation" is low on the list of bad things that can happen to your battery and, as Dan points out, reversing sulfation requires a level of sophistication not found in a trickle charger.

Bad things you can do to a battery:

Deep discharge or deep cycle. Lead, Lead Dioxide and Lead Sulfate all have different densities so, during charge, discharge, the electrodes flex and will eventually fail from fatigue. In a wet cell battery, chuncks flake off the plates and fall to the bottom of the cell until they eventually short out the cell. The deeper a battery is cycled, the bigger the problem.

Fully discharging a battery into a load can cause some of the cells to reverse polarity. A 12 volt battery is a collection of six 2 volt cells. Imagine a battery with it's terminals shorted, each cell pushing electrons through the circuit. In a perfect world, al the cells would exhaust their electrochemical energy at the same instant BUT in our world, one of the cells will die first. At that instant the discharged cell has two Lead Sulphate plates, chemically identical, and it is connected to a 10 volt supply (the other 5 cells). The poor dead cell has it's negative lead connected to the positive side of the supply and it does not have the energy to resist being CHARGED in reverse polarity by the other cells. You have probably witnessed this effect when you have tried to charge a dead battery and have seen the charging current start out very low and then build as the cells get their polarities sorted out.

Vibration. Shaking a battery is bad. Lead has low strength and high density so vibration can do a lot of damage in a short period.

Overcharging. Overcharging electrolyzes the water in the electrolyte, exposing the plates and diminishing capacity.

Temperature extremes. Batteries, especially discharged batteries are susceptible to freezing and freezing will lead to mechanical failure of the cell structure.

Good things you can do for your battery.

1) Use a linear regulator in you airplane. Older voltage regulators modulate the field current in the alternator by periodically connecting it to the full buss voltage. The average voltage from the alternator is "regulated" but the ripple voltage is large and must be absorbed by the battery.

2) Keep the battery charged. Use a voltage regulated trickle charger for long term storage.

3) Eliminate parasitic loads when the master switch is off. Use an amp meter to check the load on your airplane's battery when everything is off. Some components, like clocks, draw a small current ALL the time. It only takes 25 miliamps (0.025 amp) to fully discharge a battery in a month. Eliminate these loads or add a trickle charger to compensate for them.

4) Use a Gas Recombinant Immobilized Electrolyte battery. There is NO reason to be using a wet cell battery. GRIE batteries are a LOT better at resisting mechanical stresses than wet batteries because the plates are sandwiched between electrolyte soaked fiber pads. In wet cells, the electrodes are hanging in liquid. GRIEs are also safer, don't emit (much) corrosive gas, and will take a 100 G shock and soldier on.

5) Replace your battery every 3 years even if it is still working fine. Sooner or later it WILL fail and you can count on it failing at the worst possible time.

Regards
Brent Regan