Complete repair guide for the Roadtrek Zion – 12V Lithium Battery Bank & Solar Upgrade. Follow these steps to diagnose and fix the issue yourself.
Parts & Tools You’ll Need
- 100Ah LiFePO4 drop-in lithium battery
- Victron SmartSolar MPPT charge controller
- Victron BMV-712 battery monitor
- 40A DC-DC battery-to-battery charger
- 200W flexible solar panel
- ANL fuse holder + 200A fuse
- 4/0 AWG welding cable (battery interconnect)
- Bus bar / power distribution terminal block
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Step-by-Step Repair Guide
Step 1: Disconnect and Inspect Existing System
Start by disconnecting the negative terminal of your factory lead-acid battery and waiting five minutes for all systems to discharge completely. Inspect your current 12V wiring, fuse holders, and battery connections for corrosion or damage, as you’ll need to understand the existing layout before installation begins.
Step 2: Install ANL Fuse and Battery Cable
Connect your 4/0 AWG welding cable to the positive terminal of the LiFePO4 battery, then immediately attach the ANL fuse holder with a 200A fuse within 18 inches of the battery terminal. Run this primary power cable through your van’s interior to your main electrical compartment, securing it away from heat sources and moving parts.
Step 3: Mount Battery and Configure Bus Bar
Position your 100Ah LiFePO4 battery in your existing battery box or secure location, ensuring it’s level and protected from vibration with appropriate padding. Install the bus bar/power distribution terminal block near your battery to centralize connections for your DC-DC charger, Victron monitor, and other 12V components.
Step 4: Install DC-DC Battery Charger Module
Mount your 40A DC-DC charger in an accessible location with proper ventilation, then connect its positive input to your vehicle’s alternator charging circuit and its negative input to chassis ground. Configure the charger’s output settings to match your LiFePO4 battery’s charging profile, typically 14.4V constant voltage with temperature compensation.
Step 5: Connect Victron SmartSolar MPPT Controller
Mount the SmartSolar MPPT charge controller in a well-ventilated area away from direct sunlight, then connect your 200W flexible solar panel to its PV input terminals using appropriately sized MC4 connectors. Wire the controller’s battery output to your bus bar using properly sized cable, ensuring all connections are tight and fused according to Victron’s specifications.
Step 6: Install Battery Monitor and Network Cabling
Mount the Victron BMV-712 battery monitor on your dashboard or interior wall where you can easily view it, then connect its sense leads directly to your LiFePO4 battery’s positive and negative terminals. Connect both the SmartSolar controller and BMV-712 to your Victron Color Control GX or use their individual Bluetooth apps for remote monitoring via your smartphone.
Step 7: Test System and Verify All Functions
Reconnect your negative battery terminal and verify that all digital displays show proper voltage readings (typically 13.2-13.8V at rest for LiFePO4). Run your van’s engine to confirm the DC-DC charger activates, park in sunlight to verify solar charging current on the MPPT controller, and monitor battery percentage on the BMV-712 over several charging and discharging cycles to ensure everything functions correctly.
Recommended Parts
| Part | Link |
|---|---|
| 100Ah LiFePO4 drop-in lithium battery | View on Amazon |
| Victron SmartSolar MPPT charge controller | View on Amazon |
| Victron BMV-712 battery monitor | View on Amazon |
| 40A DC-DC battery-to-battery charger | View on Amazon |
| 200W flexible solar panel | View on Amazon |
| ANL fuse holder + 200A fuse | View on Amazon |
| 4/0 AWG welding cable (battery interconnect) | View on Amazon |
| Bus bar / power distribution terminal block | View on Amazon |