Here is what I have done. Yes, it was based on the hundreds of great builds that others have done. I studied all the many options and came up with this configuration. yes there are many others, but this one worked well for me. Some of this was covered in my trailer build posts, but here it is again all in one place.
1 TrailFX truck box (black aluminum) $280
2 110 Ah deep cycle (std marine type, not AGM) but only $100 each on sal
2 Standard battery boxes with vent tubes to outside $12 each
1 IntelliPower 45Amp DC charger. includes 3 15A 120VAC circuit breakers and 2 20A and 10 15A DC fuses ~$140
1 Homemade 1x2 wood frame (cheap!) but it is removable for servicing $5
1 BEP VSR (voltage sensitive relay) to automatically isolate jeep battery from trailer batteries. ~$70
1 West marine switch panel ~$30
2 DC 40A circuit breakers, auto-resetting (one on trailer, and one at Jeep battery)
1 DC main switch (for full disconnect of my deepcycle batteries, because I never trust my own work!) $5
1 RV Power Hatch Door ~$10
1 DC volt meter, plug in type ~$10
Various buss bars and screw terminal strips (to keep things neat)
~70 ft of 14G and 16G wire for pos and
ground for every circuit
20 ft of 10G for the battery connections to jeep and to charger
7 PIN connection to Jeep, including charging 10G wire
100 ft of wire loom $10
1 35ft RV 30A 3 prong 120V cord $40
1 30A plug to 15A plug converter $12
System was based on the plan of having 3-5 days of DC power without connecting to jeep or to AC.
Running of a DC fridge, LED lights (4 dome and 4 floods), and DC outlets for cell phones, ipods, etc.
(no air conditioners, no heaters, no electric blankets!!! )
System is about a year old now. Trailer has about 4000 miles on it (yes, mostly pavement). and system is working great.
Here is the trailer for a review. basic box with a frame around it. used cheap truck box (TrailFX) for the electrical mounted in the front. Back space is for the RTT (when I have some funds!)
Here are some views of the box setup.
Back inside the main cargo bo--. DC outlets and USB power outlets, LED dome light and DC power cord for fridge and AC power cord/outlets coming from 1 of the three 15A AC breakers. AC is for the DC/AC fridge, and with wired-in 25ft 12G AC cord I have AC power at rear of trailer. Another AC marine outlet is in front elec box on second circuit. NOTE- I decided against any AC inverter, so AC is only if I am connected to a AC power pole in a commercial campground.
I think I have everything listed. Questions? Please just ask. Dan