Borrowed a panel van to sleep in för 4 days, but we both need CPAP machines. Have 2 75ah sealed lead acid batteries. Want to charge them when driving and disconnect them from the van when engine is off. Thinking about simply parallel coupling them with starter battery via a relay and a switch and 30 amp fuse, but do I need to limit current to avoid blowing the fuse in the morning if they get empty?
We'll be using 50-90 watts which is 90/12=7.5 amps so the 2x75 ah batteries should be at 50% after 10 hours sleep. I wonder how much current we can cram in while driving, would they be charged after 4-5 hours?
u/FlukeRoads — 6 days ago