Thanks Nick, I guess I was confused about the different battery techs.
I was concerned about the heating since my multirotor motors get extremely hot and that's with a lot of airflow over them. I'll make sure to use a metal bulkhead.
I had forgotten all about the brushed ESCs. So these
can just connect right to the 2A bilge pumps? I have always seen them using relays or transistor looking regulators so didn't think about ESCs.
Also to use SLA batteries would the ESCs need to be 4S capable bc/ of the voltage?