Loading...
Most RV converters (Progressive Dynamics, WFCO, Parallax) were designed for lead-acid batteries. Plug in a LiFePO4 and the converter's float voltage (13.6V) is too low — your battery sits at 60-70% charge forever. The bulk voltage (14.4V) is also 0.2V short of LiFePO4's ideal 14.6V.
You have three options. Option 1: Replace the converter — Progressive Dynamics PD9260CV ($180-250) has a selectable LiFePO4 profile. Drop-in replacement for most RVs. Option 2: Add a standalone charger — wire a Victron Blue Smart 12/30 ($200) to the battery and bypass the converter for charging. Option 3: Do nothing — a lead-acid profile at 14.4V will charge LiFePO4 to about 80-90%. Not ideal but not harmful. The battery just never fully tops off on shore power.
⚡ Expert tip
Before replacing your converter, try option 3 for a month. Track your battery's state of charge on shore power. If it reaches 90%+ overnight, the existing converter is fine — save your $200. Only upgrade if the battery consistently stops at 70-80%.
Example calculation for your setup
Results based on a typical use case
| Appliance | Power | Usage/day | Wh/day |
|---|---|---|---|
| Compression fridge | 45W | 24h | 1080 |
| LED lighting | 20W | 4h | 80 |
| Water pump | 30W | 0.5h | 15 |
| Phone charging | 15W | 2h | 30 |
| Daily consumption | 1205 Wh | ||
Recommended LiFePO4 battery
126 Ah
(80% depth of discharge)
Recommended AGM battery
201 Ah
(50% depth of discharge)
Adjust these values with the calculator below
VANPOWERCALC PROYOUR ENERGY PROFILE
YOUR ENERGY PROFILE.
This document contains the sizing of your future electrical installation, calculated based on your appliances.
Minimum Daily Consumption
0 WH / DAY
Inventory:
SYSTEM SIZINGPage 2
Battery
To guarantee 0WH without damaging your bank (80% max discharge):
0 AH
LiFePO4 12V
Solar
Minimum power required to recharge your consumption:
0 W
via MPPT
220V AC
Maximum power (with 25% safety margin).
0 W
No Need
Safety & CablingPage 3
12V Cable Sizing Guide
Use this professional reference table to select the correct gauge (mm²) for your cables. For 12V in a van, the maximum tolerated voltage drop is 3%. Always use multi-stranded flexible automotive wire.
| Current (A) | Round trip < 2m | Round trip 4m | Round trip 6m |
|---|---|---|---|
| 5A (LEDs, USB) | 1.5 mm² | 2.5 mm² | 4 mm² |
| 10A (Fridge, Pump) | 2.5 mm² | 4 mm² | 6 mm² |
| 20A (Heater) | 4 mm² | 10 mm² | 10 mm² |
| 50A (DC/DC Booster) | 10 mm² | 16 mm² | 25 mm² |
| 100A (Inverter) | 25 mm² | 35 mm² | 50 mm² |
Fuse Sizing
The fuse protects the wire, not the appliance. Always place it as close to the power source as possible (battery or busbar).
- Wire 1.5 mm² → Max fuse 10A
- Wire 2.5 mm² → Max fuse 20A
- Wire 4 mm² → Max fuse 30A
- Wire 6 mm² → Max fuse 40A
- Wire 10 mm² → Max fuse 60A
SCHÉMA ÉLECTRIQUE
PANNEAUX SOLAIRES
0W
REGULATEUR MPPT
BATTERIE AUXILIAIRE
0 Ah
Lithium LiFePO4
FUSIBLE
FUSIBLE
BOÎTE À FUSIBLES 12V
Pompe, Leds, Frigo...
CONVERTISSEUR 220V
NON REQUI
PRO GEARPage 4
SHOPPING LIST
Where to find this equipment? Here is the community-approved selection.
12V 6-way Fuse Box
Mandatory protection
Digital Multimeter
Test your connections
Heavy Duty Crimping Tool
For perfect lugs
Heat Shrink Tubing
Insulation and safety
GENERATED BY VANPOWERCALC PRO - UNLIMITED.
About this tool
Option 3 is more common than you'd think. Many full-timers run their LiFePO4 between 20-80% and never miss the last 10-20%. The BMS handles everything safely — it just means you're not extracting maximum capacity from shore power. Solar and driving typically fill the gap. If you do replace the converter, check the amperage. Most factory RV converters are 30-55A — adequate for a 200Ah LiFePO4 bank. Larger banks (400Ah+) may want a 60-80A charger for reasonable charge times. One thing to watch: some cheap RV converters produce noisy DC output that can confuse a LiFePO4 BMS. The BMS reads voltage ripple as overvoltage spikes and cuts off charging intermittently. If your battery charges in bursts on shore power (charges for 10 min, stops, restarts), the converter's output is probably too noisy. A higher-quality converter fixes this.
Frequently asked questions
Will my RV converter damage a LiFePO4 battery?▼
No. A lead-acid converter at 14.4V will undercharge LiFePO4 (ideal is 14.6V) but won't damage it. The BMS prevents overcharge. You just won't reach 100% charge from shore power alone — typically 80-90%.
Which RV converter works with LiFePO4?▼
Progressive Dynamics PD9260CV (45A, lithium profile), WFCO WF-9855 (55A, adjustable voltage), or Victron Blue Smart IP22 (standalone, any profile). The PD9260CV is the most popular drop-in replacement.
Can I just adjust my existing converter voltage?▼
Some converters (Progressive Dynamics with Charge Wizard) have adjustable profiles. If you can set bulk voltage to 14.6V and disable the 13.2V float stage, it'll work with LiFePO4. Consult your converter's manual for adjustment procedures.
What about the noisy charging / BMS cutoff issue?▼
Cheap converters produce voltage ripple that LiFePO4 BMS modules interpret as overvoltage. The fix: replace with a quality converter (Progressive Dynamics, Victron) that has clean DC output. A capacitor bank can also smooth output but it's a band-aid.
Do I need to change anything else when going lithium in an RV?▼
Update the solar charge controller profile (if you have solar), add a DC-DC charger if your tow vehicle or engine has a smart alternator, and check that your inverter's low-voltage cutoff matches LiFePO4 specs (10.5V, not the 11.5V used for lead-acid).