The reason I don't think your going to have very good luck with light weight
bats is because I have two heavy duty deep cycle bbats in my motor home and
when you use them for a while and pull the voltage down to 12 bolts or a bit
lower my TS 440 starts acting crazy and I have used another rig with same
problems. so speaking of the cave maybe we both should. I hope I can come
visit you in my electric car. Ed K7UC