Complete repair guide for the Winnebago Revel 44E – 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: Diagnose Existing Electrical System
Before beginning any upgrades, you’ll need to disconnect the negative terminal of your factory battery and document your current 12V system’s voltage, amperage draw, and existing charge sources. Use a multimeter to verify the factory battery’s state of charge and test all existing 12V circuits to ensure they’re functioning properly before removal. Take photos of your current wiring layout for reference during reinstallation.
Step 2: Remove Factory Battery Install
Disconnect the negative battery terminal first, then the positive, and safely remove the factory lead-acid battery from the Revel’s battery compartment. Clean the battery tray and inspect the mounting brackets and surrounding wiring for any damage or corrosion that may need attention. Keep the factory battery in a safe location, as you may want to retain it as a backup or backup charger input.
Step 3: Install Lithium Battery Drop-In
Place the 100Ah LiFePO4 battery into the same compartment using the existing mounting brackets, ensuring it sits level and secure to prevent movement during travel. Connect the positive and negative terminals loosely at this stage—don’t fully tighten them yet, as you’ll need to route your new cabling first. Verify that the battery’s internal battery management system (BMS) connectors are accessible for monitoring purposes.
Step 4: Route and Secure Main Power Cables
Run the 4/0 AWG welding cable from the positive terminal of your lithium battery through a protective conduit to your power distribution bus bar, keeping the route away from heat sources and moving parts. Install the ANL fuse holder with the 200A fuse on the positive cable within 18 inches of the battery terminal as a critical safety measure. Secure all cables with adhesive-backed cable clips every 12-18 inches along their path to prevent vibration damage.
Step 5: Mount Charge Controller Components
Install the Victron SmartSolar MPPT charge controller and BMV-712 battery monitor in an accessible, well-ventilated location near your battery compartment, such as inside your electrical cabinet. Ensure the components have adequate airflow and are mounted away from water sources, using the provided mounting brackets and hardware. Position the components so their display screens are visible and their cable connections are easily accessible for troubleshooting.
Step 6: Wire Solar Panel and Controllers
Connect the 200W flexible solar panel to the SmartSolar MPPT charge controller’s input terminals using the appropriately sized solar-rated cable, then connect the controller’s output to your battery bus bar and lithium battery. Wire the BMV-712 battery monitor across the main battery terminals to provide real-time voltage, amperage, and state-of-charge data to your Victron system. Install the DC-DC battery-to-battery charger between the Revel’s alternator circuit and your lithium battery to capture charging while driving.
Step 7: Test All Systems for Safety
Power on each component individually and verify proper voltage readings on your multimeter and through the Victron app—your lithium battery should read approximately 13.2-13.6V at rest. Connect a known load (such as a 12V light or fan) to confirm current draw is being registered correctly on the BMV-712 monitor and that the solar controller shows proper panel input. Document all baseline readings and test the battery monitor’s alarm functions before taking your Winnebago Revel on an extended trip.
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 |