I've done this with beef patties; so I imagine the application would be the same.
When I freeze my patties: I will first take a sheet of parchment paper, with my chef's knife I'll cut them into 4"-5" squares. The next step requires a gallon plastic bag. I will arrange four of the patties in each corner of the bag, and then layer another four patties on top. During this, I layer the parchment squares appropriately, so that the patties are sandwiched by the parchment squares. This will total eight patties per gallon bag.
The parchment will make the patties easy to separate from the bag and patty peers.
Of course, I'm sure more enlightened users on this site could offer better suggestions. But in my experience, I have found this method to be effective and practical for the "at home" chef.