Leisure Travel Vans Unity – 12V Lithium Battery Bank & Solar Upgrade

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Complete repair guide for the Leisure Travel Vans Unity – 12V Lithium Battery Bank & Solar Upgrade. Follow these steps to diagnose and fix the issue yourself.

Parts & Tools You’ll Need

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Step-by-Step Repair Guide

Step 1: Diagnose System and Prepare Safely

Before beginning installation, you’ll need to disconnect your existing battery system completely and allow all capacitors to discharge for at least five minutes to prevent electrical shock. You should also verify your van’s current electrical draw, existing battery capacity, and solar exposure patterns to confirm this upgrade meets your power needs and that your roof space accommodates the 200W panel.

Step 2: Install Battery Disconnect and Fusing

You must mount the ANL fuse holder with the 200A fuse between your battery positive terminal and the main electrical system, positioning it within 18 inches of the battery as a critical safety requirement. You should use the 4/0 AWG welding cable for this connection, securing it with proper crimped terminals and heat shrink tubing to ensure a reliable, low-resistance connection.

Step 3: Mount LiFePO4 Battery and Secure

You’ll position the 100Ah LiFePO4 battery in your van’s designated battery compartment, ensuring it sits level and is secured with appropriate battery box straps or brackets to prevent movement during travel. You should verify the mounting location allows adequate ventilation and access to the battery’s terminals and display screen for future monitoring and maintenance.

Step 4: Install Bus Bar and Distribution

You need to mount the power distribution terminal block (bus bar) near your battery bank, connecting your positive and negative battery cables to the appropriate bus terminals using properly sized crimped lugs. You should ensure all connections are tight and the bus bar is accessible for connecting your charge controller, battery monitor, DC-DC charger, and other loads.

Step 5: Wire Victron SmartSolar Charge Controller

You’ll connect the Victron SmartSolar MPPT controller between your solar panel input and the battery bus bar, following the wiring diagram to properly connect positive and negative from both the panel and battery terminals. You should run the solar cable through conduit along your roof and down the interior walls, securing it appropriately and keeping it separate from other electrical lines to minimize interference.

Step 6: Connect Battery Monitor and DC-DC Charger

You’ll install the Victron BMV-712 battery monitor by connecting its shunt in series with your battery negative terminal, then running the monitor display to an accessible location inside your van cab or living space. You should wire the 40A DC-DC charger between your vehicle’s alternator circuit and the lithium battery bus bar, ensuring it has appropriate fusing and following Victron’s connection guidelines for proper engine-start charging integration.

Step 7: Test System and Verify All Connections

You must power up the system with the battery disconnect switch, checking that all Victron devices display properly and show correct voltage readings on both the monitor and charge controller screens. You should verify solar charging by monitoring the SmartSolar controller output during daylight hours, test the DC-DC charger by running the vehicle engine, and confirm all connections are secure and free from corrosion before your first trip.

Recommended Parts

PartLink
100Ah LiFePO4 drop-in lithium batteryView on Amazon
Victron SmartSolar MPPT charge controllerView on Amazon
Victron BMV-712 battery monitorView on Amazon
40A DC-DC battery-to-battery chargerView on Amazon
200W flexible solar panelView on Amazon
ANL fuse holder + 200A fuseView on Amazon
4/0 AWG welding cable (battery interconnect)View on Amazon
Bus bar / power distribution terminal blockView on Amazon