Who's the idiot that said fast speed techniques and strength? That' wildly unhelpful. How do you win a drag race? Go fast. No $#!% Sherlock, you figure that one out by yourself?
As to the question, are we looking to avoid being disarmed with a battle hammer, as in you are the person with the battle hammer? Or are we talking about unarmed person disarming a person with battle hammer?
Very quickly, please note that war/battle hammers in movies and games are not at all accurate. Historical war hammers has much more in common with the standard nail hammers than war hammers from the medias. So we are looking at fairly light and quick percussion weapon.
As with all percussion weapon the goal is to stay out side of the attackers range, and then burst in when you see a chance. With percussion attacks the most dangerous spot is at the top of the arc, and closer you get to the center of the circle safer you are. For example if a person was swing a hammer and if you got hit with the metal part of the hammer it'll do damage, the wooden handle part would hurt less, the hand holding the hammer even less pain, forearm wouldn't hurt at all, and upper arm wouldn't really register. So there is very specific distance where the hammer is effective, and if you close that distance, then you can start applying grappling techniques to disarm or throw the hammerman and escape the situation.
If you are the hammerman, then you are going to have to use your foot work to keep the other person from closing the distance and yet close enough to strike. The distance itself will be a hammer length longer than standard punching range. Also you wouldn't keep the hammer in front of you like a sword since there is no sharp point to keep the opponent from charging in like the sword. You would keep the hammer in some sort of high guard or the like from another angle, so that you can strike with full force quickly.