I put mine on ice. What I use is a large Sams bag (freezer bag $12.00). I freeze 32 ounce bottles and depending how warm it is will determine how many I use.
When the fish come home they are still flopping when undergoing the knife.
The bag makes it easy to carry and switch out. My wife fillets all my fish. All we do is switch a clean bag with fresh ice out for a bag full of fish.
You can get as many as 60 large crappie in the bag with one 32 ounce ice bottle on the bottom and one 32 ounce bottle on top.
D