This is a great idea. I'm actually researching DIY solutions to electrifying my boat (I was a USAF electrician, once upon a time) and the prepackaged battery so

This is a great idea. I'm actually researching DIY solutions to electrifying my boat (I was a USAF electrician, once upon a time) and the prepackaged battery solutions are so expensive and inflexible. (Granted, for marine use there are some extra considerations...)