RV converter/charger
PowerMax PM3-55LK 55A Converter, Lithium Specs and Sizing
Researched from published standards and manufacturer specifications. Updated .
Quick answer
This is a specification sheet rather than a review. Every figure below comes from the manufacturer listing, and we do not test products in person. What this page adds is context: what these numbers mean for an RV system, and what else you need to buy alongside it.
Best for: The converter swap that has to happen with a lithium conversion.
PowerMax PM3-55LK 55A Converter, Lithium specifications
| Specification | Value |
|---|---|
| Amps | 55 |
| Lithium Profile | Yes |
| Mount | Deck mount |
Published standard Source: Manufacturer listing. Specifications and pricing change without notice. Confirm on the listing before buying.
What does this component need alongside it?
Check the cable size, the fuse rating and the compatibility with your battery chemistry before installing this component.
How does it compare with other rv converter/charger options?
| Component | Price | Notable spec |
|---|---|---|
| PowerMax PM3-55LK 55A Converter, Lithium | $133.00 | amps: 55 |
| PowerMax PM4-55A 55A Converter, Lithium | $143.00 | amps: 55 |
| WFCO WF-9855-AD-CB 55A Converter/Charger | $248.99 | amps: 55 |
| VEVOR 55A RV Converter with 4-Stage Charging | $64.84 | amps: 55 |
Published standard Source: Manufacturer listings.
PowerMax PM4-55A 55A Converter, Lithium
$143.00Selectable output voltage lets you match the pack rather than accepting a fixed lead-acid setpoint.
Best for: A build where the charge voltage has to be set exactly.
Check price on Amazon
WFCO WF-9855-AD-CB 55A Converter/Charger
$248.99The genuine WFCO deck-mount unit, which matters because the WF-9855 slot is what most trailers are already wired for.
Best for: A direct drop-in replacement in a WFCO power center.
Check price on Amazon
VEVOR 55A RV Converter with 4-Stage Charging
$64.84Four-stage charging at the lowest price in this group, though it lacks the published profile documentation of the PowerMax units.
Best for: A budget converter replacement.
Check price on AmazonRV converter/charger options
PowerMax PM3-55LK 55A Converter, Lithium
$133.00A lithium-specific charge profile. A stock lead-acid converter will never take a LiFePO4 bank to full, which is the single most common lithium conversion mistake.
Best for: The converter swap that has to happen with a lithium conversion.
Check price on Amazon PowerMax PM4-55A 55A Converter, Lithium
$143.00Selectable output voltage lets you match the pack rather than accepting a fixed lead-acid setpoint.
Best for: A build where the charge voltage has to be set exactly.
Check price on Amazon WFCO WF-9855-AD-CB 55A Converter/Charger
$248.99The genuine WFCO deck-mount unit, which matters because the WF-9855 slot is what most trailers are already wired for.
Best for: A direct drop-in replacement in a WFCO power center.
Check price on Amazon VEVOR 55A RV Converter with 4-Stage Charging
$64.84Four-stage charging at the lowest price in this group, though it lacks the published profile documentation of the PowerMax units.
Best for: A budget converter replacement.
Check price on AmazonFrequently asked questions
- What is the PowerMax PM3-55LK 55A Converter, Lithium best for?
- The converter swap that has to happen with a lithium conversion. A lithium-specific charge profile. A stock lead-acid converter will never take a LiFePO4 bank to full, which is the single most common lithium conversion mistake. Confirm the current specification on the listing before buying, because manufacturers revise these products without changing the model name.
- Is the PowerMax PM3-55LK 55A Converter, Lithium suitable for a lithium system?
- Yes. This component either is a LiFePO4 battery or carries a genuine lithium charge profile, which is the specification that matters. A charger without a lithium profile will not bring a LiFePO4 pack to full charge.
- What size cable and fuse does it need?
- That depends on the current it carries and the length of the run, not on the component itself. Work out the current from its rating, then size the conductor for both ampacity and voltage drop with the wire gauge calculator, and fuse it at 125 percent of the continuous load rounded up to the next standard rating.
Wiring safety. Never exceed a conductor's rated ampacity, and always fuse a circuit at or below what the wire can carry, because the fuse protects the wire rather than the appliance. Fuse every positive conductor as close to the battery as practical. Use proper crimped lugs and heat shrink rather than twisted joints, support cable so it cannot chafe through on a frame edge, and keep the battery compartment ventilated. Permanent AC wiring is work for a qualified RV technician or a licensed electrician.