by troubleScottie » Thu Oct 13, 2022 11:30 am
There are nice chargers that cover a wide range of battery types.
REDARC Electronics Dual Input 40A in-Vehicle DC Battery Charger : about $400; over your price point, but a great product, could be used in conjunction with a solar setup (two inputs)
Renogy 12V 60A DC to DC On-Board Battery Charger : about $200 on Amazon; supports multiple battery types, only a single input. You could use switches to select more than one source.
You would really have to add wiring (10 gauge or smaller (bigger diameter) depending on distance), solenoid, fuses, Anderson connectors, more wiring, glands from the vehicle battery to the trailer to make everything work. Think high power car audio system (do people still do that?) The 12V power wire on a 7 pin connector is not rated to carry high current (40-60 amps) -- more like minor charging like an electric brake battery charger.
Given possible Lithium battery charging issues, I would not skimp on this part of your build.
BTW: I do not think AGM profile is close to the same as Lithium profile. It is still very much a lead acid battery system.
Michael Krolewski
Scottish Terrier Fancier