For the price, large cooler seems the perfect application. Especially if you can get a cheap flat deck for the back end to secure it on. Doesn't have to be a yeti or anything, but it's going to me more durable than a sterilite tote, and the temperature stability is great for the batteries, food, or whatever else. Mount rod holder clips to the lid, you can make dividers to keep your gear organized in the bottom. Sounds like a great, cheap(er) solution!