WF-9855 55 Amp RV Power Converter for Lithium Battery - Reliable

In this review the WF-9855 55 Amp RV Power Converter is evaluated for owners who run lithium house batteries in their RVs. The bottom line: it is a focused replacement or upgrade for WF-9800 series installations that need a converter designed specifically for lithium chemistry, with a clear benefit being its three-stage charging that brings a 12V system up to 14.6V then holds in a trickle state to maintain health and prolong battery life.

Key Features

• Designed for lithium battery: Built to be compatible with WF-9855, WF-9855-AD, WF-9855-LIS and other WF-9800 series units so it fits common RV converter form factors and wiring.
• Three-stage charging: Raises battery voltage to 14.6V then shifts to reduced power trickle mode to keep lithium cells topped without overcharging.
• High output capacity: Delivers up to 55 amps at 14.6V (950 watts) to support multiple loads and recharge larger house banks on the road.
• Comprehensive protections: Built-in overcharge, overvoltage, overcurrent, high temperature and short-circuit protections protect both battery and RV wiring.
• Quiet cooling: A temperature-controlled fan with a quieter motor reduces noise and runs only when needed to manage heat efficiently.
• Manufacturer support: Backed by a 2-year free warranty from the maker, which helps with confidence during installation and early use.

Who It's For

This converter is aimed at RV owners who have switched to or purchased lithium 12V house batteries and need a drop-in compatible charger for the WF-9800 family. It is a good fit for those who want a robust 55 amp supply to support appliances and to recharge battery banks reasonably quickly while parked or plugged in.

It is less suited to users who still rely on lead-acid specific charging profiles or who require integrated inverter/charger combos; those buyers should seek a unit tailored to lead-acid settings or a combined inverter solution instead.

Pros & Cons

Pros

• Specific lithium profile and three-stage charging help extend lithium battery life and maintain charge.
• Strong 55 amp output and 950 watt power rating support heavier RV loads and faster recharge.
• Multiple safety protections provide peace of mind for wiring and battery protection.
• Quiet, demand-controlled fan reduces audible noise compared to similar chargers.

Cons

• Not intended for lead-acid charge profiles, so users with non-lithium banks must choose a different converter or risk improper charging.
• Installation requires compatibility with WF-9800 series form factor and wiring, so exact fitment should be confirmed before purchase.

Specifications

Power	950 Watts
Output Current	55 Amps
Output Voltage	14.6 VDC
Input Voltage	105-130 VAC, 60 Hz
Cooling	Quiet, temperature-controlled fan
Protections	Overcharge, overvoltage, overcurrent, high temp, short circuit
Warranty	2-year free warranty

Our Verdict

The WF-9855 55 Amp converter is a practical, value-minded choice for RV owners running lithium house batteries who need a WF-9800 series compatible unit. Its dedicated lithium charging profile, solid 55 amp output and layered protections make it a reliable converter that balances performance with quiet operation and manufacturer support.

Frequently Asked Questions

Will this unit charge lithium batteries correctly?
Yes, it uses a three-stage charge that raises voltage to 14.6V then shifts to trickle mode, which is the recommended approach for many lithium 12V systems.

Is the fan noisy during operation?
The converter uses a temperature-controlled, quieter motorized fan that runs only when needed and is reported to be noticeably quieter than many similar chargers.

Can it replace other WF-9800 series converters?
It is compatible with WF-9855, WF-9855-AD, WF-9855-LIS and other WF-9800 series units, but confirm mechanical fit and wiring before installation.