first post. first grenadier. first time building out a dual battery system

[SHK]

thanks all for any help here

After a lot of reading, and chat gpt... I have this plan. US station wagon
tie the primary stock battery via a redrac BCDC charger 40A to a 100Ah RB100-LT relion lithium battery and supply accessories off of the lithium battery via a busbar and distribution block. I have also the intention to reroute the EXT high load overhead panel (ideally just EXT 2 and 3 for the grab bar deutch outlets) so I can power lights off of the lithium instead of the stock. I am also adding An electrical link to jump start the primary battery from the auxiliary lithium battery if needed. blue boxes are stock and the rest of the diagram I am adding. the littelfuse boxes are two busbars that are stock on the wagon and I believe I can tap into it for my second battery. let me know what you guys think with especial attention to the electrical wiring ? would be very helpful to have some input .

 

[parb]

I'm about to embark on the same adventure. I too want to keep the roof Deutsch connectors energized with my lithium battery. I'm going for the redarc alpha 50 due to the built-in "charge my starter battery" capability.

I haven't researched how to energize the hi load panel. I'm thinking that I'll energize the relays going to the roof taps from this battery but I haven't really decided yet.

I'll follow with interest.

I was planning to wire my redarc dcdc directly to the primary battery. I figure that if wire it to the little fuse I may overload that circuit if it's pulling full power while charging my lithium battery at 50A. Seems safer to install a post mounted fuse to the starter battery and wire that into the redarc.

My few cents