Where This Guide Comes From
The method, the wiring order and every number below come from the source video — EXPLORIST life's complete electrical rebuild of a retired couple's travel trailer, filmed start to finish. If you want to watch the build before you read the breakdown, it's right here:
What makes this build worth copying is that the camper started out ordinary. No generator. No existing solar panels. Just a factory 30-amp electrical system like the one in most trailers built in the last decade. If you have a standard travel trailer, this is about as close to your own project as you can get.
I've written the whole thing out in order — what they walked through first, how the battery bank went in, how the inverter got spliced into the OEM wiring, how the solar went up, and the exact charge settings they programmed at the end. You can follow along with your own rig, or at least know what to ask for before you hand this to a shop.
Before You Start: What This Install Looks Like
The goal here was simple: make the trailer self-sufficient off-grid so Kurt and Laurie could park anywhere. The shopping list ended up being:
- One 270Ah Battle Born GC3 lithium battery (12V, 3,456Wh usable)
- A Victron Lynx Distributor as the single power-distribution point
- A Victron MultiPlus 12V 2000VA inverter/charger for the 120V side
- 800W of solar on the roof, wired in series
- An upgraded alternator charging path
Two things worth noting before we start. First, this camper had no pre-existing solar and no generator — the team calls that the easiest starting point, because you're not untangling somebody else's system. Second, the one genuinely tricky part was getting the inverter wires from the front of the camper back to the OEM breaker box wiring. Keep that in mind when you scope your own job: it's rarely the battery that's hard, it's the routing.
Step 1: Walk the Factory Electrical System Before You Touch Anything
The team started with a full walkthrough of what was already in the camper, and it's the step most people skip. They checked four things:
- The OEM battery, up front on the tongue — this is the existing house bank you're replacing.
- The shore power inlet, at the back — a standard 30-amp inlet feeding the whole trailer.
- The roof — plenty of empty roof space for panels, plus a factory "solar ready" gland with two MC4 connectors already poked through, wired down into a storage pass-through at the front.
- Inside — a 120V breaker box and a 12V DC fuse block, and the key question: which wire feeds the breaker box from the shore power inlet.
That last wire matters, because it's the one you'll splice the inverter into. The team traced it from the 30A inlet at the back, up to the 120V breaker box. Find that feed wire in your own trailer before you buy anything — take photos, label it, and you've already de-risked half the job.
They also dealt with the solar-ready wiring the right way. The two MC4 wires from the roof gland weren't labelled, so instead of guessing, they grabbed a multimeter and checked voltage on each: the wire with power runs to the OEM battery bank, the one without power runs up to the roof panels. The powered one got capped off (they'd already run their own power wires to the Lynx Distributor); the dead one got butt-spliced to their new solar wiring. A five-minute multimeter check that avoids a whole class of "why is my solar feeding the wrong thing" problems.
Step 2: One Big Lithium Battery Beats Three Small Ones
The team's choice here is the detail most people miss: instead of three smaller lithium batteries wired together, they used a single 270Ah Battle Born GC3.
Why does that matter? Fewer batteries means fewer parallel connections, fewer busbar links, less cable, and less space. The GC3 is a big format cell designed to replace a full bank in one unit. Installation was as simple as securing the battery to the floor, then connecting positive and negative — no balancing between batteries, no inter-battery wiring to get wrong.
For most RV owners this is the single most practical lithium upgrade decision you can make: one manufactured, BMS-protected battery beats a DIY bank of smaller cells every time, for safety and for total cost once you count the extra cable, lugs and fuse holders.
Step 3: Wire It All Through a Lynx Distributor
This is the step with the most small parts, and the team's order of operations is worth copying exactly, because a missed step throws off the whole system. Here's the sequence:
- Prep the cables. Use the barrel of the lug as the measurement for how much insulation to strip — no guessing. Strip both ends of the positive wire, then do the same for negative and equipment ground.
- Crimp the lugs, positioned so the wire doesn't twist when installed. Add heat shrink over the lug for protection and strain relief.
- Sand the lugs, terminals and adapters, then wipe everything down with alcohol. This sounds fussy, but it's the difference between a solid connection and a hot spot five years later.
- Build the positive side: bolt through washer → Lynx Adapter → Distributor busbar → washer → lock washer → nut, snugged. Add the master disconnect switch on the adapter.
- Fuse the battery feed: an MRBF fuse on its holder, with the 5/16" lug from the positive wire on top, secured washer / lock washer / nut.
- Build the negative side the same way, then add the shunt (BMV-712 battery monitor side facing the distributor) and connect the negative cable lug.
- Wire the BMV-712 power lead, trimming and butt-splicing it to length.
The lesson here: a distributor like the Lynx isn't optional wiring bling. It gives you one fused, switchable, monitored connection point, which makes the whole system safer to work on and easier to troubleshoot. If you're speccing your own system, the equivalent is a quality busbar + fuse block + battery monitor — the brand matters less than having all three.
Step 4: Splice the Inverter/Charger Into the OEM Wiring
Powering the 120V outlets from the new battery (and recharging from shore power) means a MultiPlus inverter/charger — in this build, the 12V 2000VA unit. The intimidating part is connecting it to the factory system without wrecking the OEM wiring, and the team's approach is the cleanest I've seen:
- A VE.Bus Smart dongle goes on the inverter's VE.Bus port, giving Bluetooth control through the VictronConnect app — that's how you later see live charge status on your phone.
- AC input and output are wired with 10/3 cable: black to L, green to PE, white to N on both the input and output sides, each wire labelled before routing.
- The other ends land in a 30A OEM RV splice kit — basically user-friendly terminal blocks on a DIN rail that pass power through, pre-assembled on the bench before the parts ever go into the camper.
The pre-assembly detail is the trick worth stealing: build the splice box on your workbench, label everything, then install. It turns a scary "cut into my RV's AC wiring" job into a bolt-in one. Mounting was a plate on the wall, inverter on the plate, screws in, cover on.
Step 5: Add 800W of Solar, Wired in Series
With the battery and inverter done, the team moved the panels up top. Four panels at roughly 200W each, and the process is straightforward:
- Mount Z-brackets to the panels first, with the included hardware — four per panel.
- Take the solar isolator off before working up there. Yes, even though panels aren't connected yet — it's a habit that pays off when they are.
- 3M VHB tape on the bottom of each bracket, panels placed, bracket positions traced, roof cleaned with alcohol.
- Secure with large self-tapping screws, peel and stick the tape, then repeat for every bracket of every panel.
- Wire the array in series: positive of one panel to negative of the next, then the array's two ends connect to the PV connectors at the factory roof gland.
- Seal everything — sealant over and around every mounting foot, and over the screws of the wire clamps, so water can't find its way in.
Two real-world details from this install: the panels' built-in wires reached each other and the roof gland, but the furthest one didn't, so the team made a small extension with a male connector on one end and a female on the other. And with everything wired in series, you get higher voltage and lower current on the roof run — which means smaller cable and less loss on the way down to the charge controller.
Series wiring is the right default for a small 800W array into a 12V system, because the higher string voltage keeps the current low enough for a standard PV cable run through the roof.
Step 6: Program the Charge Controller So the Numbers Match Your Battery
Here's the part most guides never show — the actual settings. The team used the VictronConnect app, and these are the values they put in for a 270Ah 12V Battle Born bank:
| Setting | Value | Why |
|---|---|---|
| Battery preset | User defined | You're telling the controller exactly what's connected, not trusting a generic profile. |
| Expert mode | On | Unlocks the fields you actually need. |
| Absorption voltage | 14.6V | Standard LiFePO4 absorption target. |
| Float voltage | 13.5V | Low, because lithium doesn't really need to float. |
| Equalization voltage | 14.4V, then disabled | Lithium doesn't equalize; the number is set low enough that an accidental cycle won't hurt. |
| Adaptive absorption | On, 30 min per 100Ah | 270Ah → roughly 1.5 hours of absorption. |
| Temperature compensation | Off | Not needed for this chemistry; leave it off. |
Notice the pattern: the voltages match Battle Born's own spec sheet, the float is deliberately low, equalization is off, and absorption is adaptive. If you swap in a different lithium battery, don't copy these numbers blindly — pull the spec sheet from your battery and set absorption/float from that. Getting this wrong is the most common reason a lithium install "works" but never reaches full.
Test It as a Whole — and What We'd Budget For Next
With everything wired, the team turned the master battery switch on, then the solar isolator, and opened VictronConnect. The charge controller appeared on the list, firmware updated, and the home screen showed power being produced immediately — solar coming in, and you can leave solar, alternator and shore power all on at once, because each source regulates and synchronizes on its own.
One honest note from the video: this camper relies on the alternator for charging while driving, and the team points to a separate build where they installed dual Victron Orion chargers for faster alternator charging. If you boondock a lot and drive long days, budget for a good DC-DC alternator charger — the alternator path is where most RV lithium systems leave performance on the table.
The end state: Kurt and Laurie got a self-sufficient, off-grid travel trailer — quiet campgrounds optional. And that's the whole point of a build like this. It's not about the brand of the parts; it's about a system that's one switch to turn on.
And if you're not hunting for a consumer brand but need the lithium RV battery bank itself — a custom LiFePO4 pack at a specific voltage and capacity, an OEM or ODM project, or wholesale supply for your own product line — that's what we do. Dajiu Energy is a Chinese manufacturer building LiFePO4 batteries for RVs, homes, golf carts and portable applications since 2017. Our product range covers LiFePO4 drop-in replacement batteries, EV and golf cart batteries, wall-mounted home storage, portable power stations, commercial energy storage and battery swap cabinets — explore the full lineup in our product center, or browse more buying guides. Tell us your voltage, capacity and size, and we'll engineer the pack to hit it.
Bottom Line
Six things to remember from this build:
- Walk the system first. Trace the shore power feed, find the roof wiring, check the breaker box — before you buy a single part.
- One big lithium battery beats a bank of small ones for wiring simplicity and safety in most trailers.
- A distributor (or its equivalent) — busbar, fuses, battery monitor — is what makes the system safe to work on.
- Pre-assemble and label the inverter splice kit on the bench; the AC side is the only genuinely scary part.
- Solar in series keeps roof-run current low, and seal every mounting screw.
- Program the charge controller to your battery's spec sheet — absorption, float, equalization off, temperature compensation off. That's the step that decides whether you ever reach 100%.
None of this requires brand loyalty to any specific manufacturer. What it requires is understanding your trailer as one system — battery, distributor, inverter, solar, charging sources — and then the build is just order of operations. If you've been putting off an off-grid upgrade because the YouTube rabbit hole looked endless, this is the install that should bring you back.
What Our Readers Asked (Top Comments on the Video)
These are the most-liked comments on the source video, with our practical answers. The original creators did not reply to most of these threads, so the answers below are ours — written the way we'd answer a customer on the shop floor.
Source video: EXPLORIST life — "RV Electrical System Solar and Lithium Battery Upgrade - Start-to-Finish Guide" (youtube.com/watch?v=KM_8s4cTjWA). Comment excerpts are quoted verbatim from the video's top comments; the original creator did not reply to these threads, so all answers are Dajiu Energy's own.