Originally Posted by ThomasC
I had that idea. Put some of your battery bank in your TV and maybe even a solar panel
on the cab or the cap. The problem with the idea is how to connect the two systems together when they are at different charge levels. It is a huge no-no connecting batteries in parallel when they have different voltages. The batteries try to equalize instantly and huge amounts of current can surge though the system. In other words sparks will fly.
I was speaking from ebike experience where I run parallel packs. The pack voltage is 84 fully charged and if you are off a few volts when you connect them the surge can get you in trouble.
Now in a 12 volt system the voltage differential will be less, maybe a volt, so there will be a smaller chance of a problem. This thread is turning into the differences of opinion that occur in the ebike forums when talking about paralleling packs. I don't follow conventional wisdom on the ebike forums and have been criticized for some of the things that I do.
Perhaps I was being overly conservative here but we have to remember there is a vast difference between working with a lead acid system and a Li-Fe-ion system because of the BMS that is built into lithium batteries. Lithium batteries have the potential to transfer huge amounts of current very quickly compared to lead acid setups.