Why Get a Lithium Compatible RV Converter?
Lithium batteries are becoming the go-to choice for RVers because they’re lightweight, charge faster, and last much longer than traditional batteries. But without the right converter, you won’t be getting the full benefits. You might even be damaging your RV battery.
Lithium compatible RV converters like the PowerMax PM3-55LK, are designed specifically to work with lithium batteries, while still being compatible with older battery types.
Related Product: Keep your new RV converter safe with a Kohree RV Surge Protector (click to view on Amazon)
It gives you the flexibility and performance you need for today’s RV batteries while still being reliable enough to keep your 12 volt electrical system running smoothly.
In this article, I’ll break down the features of the Powermax Converter, share my review, and walk you through how to install it in your RV to make your setup lithium ready. I’ll also answer some common questions to help you decide if this is the right upgrade for you.
See Also: Best Lithium Battery Chargers & Which One You Should Get
PowerMax PM3-55LK RV Converter
Main Features
- Lithium-Compatible Charging – Specifically designed to handle the higher voltage charging requirements of lithium-ion batteries for maximum efficiency and performance.
- Multi-Battery Compatibility – Works with both lithium and traditional lead-acid batteries, providing flexibility for mixed battery setups or gradual upgrades.
- Adjustable Output Voltage – Features adjustable 13-16.5 volt settings, allowing you to fine-tune the charging process for different battery types or specific needs.
- 55-Amp Output – Provides up to 55 amps of power, ensuring fast and reliable charging for your RV battery system.
- Built-in 3-Stage Charging – Includes bulk, absorption, and float stages to safely and efficiently charge and maintain RV batteries.
- Compact and Lightweight Design – Easy to fit into tight RV spaces while keeping your setup as lightweight as possible.
- Quiet Operation – Designed to run quietly, so it won’t disturb you during use.
- Overload and Overheat Protection – Built-in safety features protect your system from damage caused by overheating or excessive load.
- Plug-and-Play Installation – Simple design makes it easy to replace your old RV converter or add it to your camping setup.
PowerMax Lithium Compatible RV Converter Review
After using the Powermax RV Converter/Charger to upgrade my campers’s power system, I can say it’s a great option for anyone looking to make their setup lithium-compatible without breaking the bank.
It does what it’s supposed to: charges 12-volt lithium batteries efficiently and reliably and converters 120V power to 12 volt power when you’re plugged in.
Plus, it’s compatible with other types of batteries, which adds flexibility if you ever need to switch back to lead-acid or AGM batteries.
Compared to other converters designed specifically for lithium batteries, this one is much more budget-friendly. For RVers who want to upgrade without overspending, it’s a solid deal.
See Also: What will happen if I charge a lithium battery with my RV?
That said, there is one downside I encountered was some misinformation. The Amazon listing claimed this was a 4-stage charger, but in reality, it’s a 3-stage charger.
That was disappointing, as I might have considered a different option had I known this upfront. Still, it gets the job done, and I’m satisfied with its performance overall.
If you’re looking for an affordable way to make your RV lithium-ready while keeping the option to use other battery types, the Powermax Converter is worth considering. Just be aware of its actual specifications before making your decision.
Buy This If You
- Are Upgrading to Lithium RV Batteries
- Want Compatibility with Multiple Battery Types
- Want a Budget-Friendly Upgrade
- Need to Replace a Failing Converter
- Are Looking for Adjustable Voltage Settings
Don’t Buy This If You
- Need a True 4-Stage Charger
- Want Advanced Monitoring Features
- Have a Very High Amp Requirement (Click Here to Find 100 Amp Option on Amazon)
- Want a Converter Specifically Designed for Lithium Batteries
Lithium RV Converter Easy Installation
Replacing the converter in an RV seems daunting at first, but most RV owners who know how to handle small repairs should be able to do this. Especially if the original converter is around the same size as the new one, which most usually are.
The only real issue I ran into was the feet that stick out the sides. They made the PowerMax just a little wider than the original, so I had to get out the grinder and remove about 1/2 an inch from each foot.
Step 1: Safety First
Start by unplugging your RV from any power source and disconnecting the battery (or batteries, if you have multiple). This step is critical because you’ll be working directly with both the 12-volt and 120-volt systems.
Skipping this step could result in serious injury or damage.
Step 2: Remove the Old RV Converter
You’ll need to get into the power center of your RV. Usually all you have to do is remove the front cover and you will see the RV converter underneath the fuse panel.
There should be 4 wires attached to the converter, two from the battery and two from the main electrical system.
In my case, the old converter was mounted on a sliding shelf secured by two screws. After removing the screws, I cut the four wires as close to the converter as possible so I could remove it completely.
Step 3: Prepare the PowerMax RV Converter
As soon as I pulled out the new PowerMax PM3-55LK I knew some alterations would need to be made. It came with two terminals for the large battery cables, but on the 120 volt power side there was a plug instead of direct wire connections.
To prepare it for installation, I removed the PowerMax cover and found that the plug was connected to the main circuit board using common blade connectors. I unplugged the main wires, unscrewed the ground wire.
I left the cover off for the next part so I could plug the RV wires into the new RV converter.
Step 4: Prep Wires & Mount the New RV Converter
Before connecting any wires to the PowerMax I first stripped them and made sure the new RV converter could fit where the old one was.
It was an exact fit for length and height. I was even able to remove the plastic shelf from the old RV converter and mount it to the bottom of the PowerMax.
The only hiccup was the side-mounted feet on the PowerMax, which made it slightly too wide. A few passes with a grinder resolved the issue.
In older RVs, unexpected issue always happen. Thankfully, this was an easy fix.
I also added some blade connectors to the black and white RV 120 volt wires.
Step 5: Connect Wires & Test
Connecting the wires is very straightforward. The battery cable terminals are color coded so you know where to connect the positive and negative.
I took photos of the circuit board before I removed the plug to note which blade connectors were positive and negative.
If you’re installing a PowerMax RV converter and you don’t know what cable goes where. The negative is the outer blade connector, and the positive is the inner one.
After connecting everything I tested the new RV converter to make sure it could convert 120 volt power to 12 volt and properly charge a 12 volt lithium battery.
To test, I plugged the RV into shore power and turned on the lights. There was a slight hum from the PowerMax but the lights worked fine.
I also tested the pump and fans to make sure the new converter could handle the load correctly. It worked great.
Next, I connected the lithium battery to the RV. The converter started to charge the battery and the LED indicator light on the right side was showing green so I put the cover back on and slid the PowerMax into place.
Step 6: Charge Voltage Adjustment
After a few hours the lithium RV battery stopped charging so I tested the charge voltage to make sure the PowerMax was set up correctly for 12 volt lithium batteries.
To monitor the voltage output I put multimeter pins on the battery cables coming out the right side of the RV converter. The charge voltage was lower than it needed to be to fully charge the lithium RV battery, which is why I needed to change it out in the first place.
With the multimeter still on the battery cables I turned the voltage adjustment screw until it was outputting 14.6 volts. Which got the battery to start charging again.
Step 7: Replace Cover & Enjoy
That was pretty much it. I was able to do the entire installation in about an hour. It took a little longer because I had to grind the feet off, but the main installation part was really easy.
Now I don’t have to worry about my RV lithium battery not fulling charging whenever I use shore power. It’s also quieter than the old converter that seemed to be on its last leg anyways.
RV Converter FAQ
1. Why do I need a lithium compatible RV converter?
Lithium batteries charge differently from traditional lead-acid batteries. They require a higher and more precise voltage to reach full capacity and maintain their longevity.
Traditional RV converters aren’t designed for this and may undercharge or even damage lithium batteries.
A lithium compatible RV converter ensures your batteries charge fully, efficiently, and last as long as possible.
2. Can I use a lithium compatible RV converter with lead-acid or AGM batteries?
Yes! Most lithium compatible RV converters, including the PowerMax PM3-55LK, are designed to work with both lithium and traditional battery types.
This flexibility is great for RVers who may have a mix of battery types or are transitioning to a full lithium setup over time.
3. Do I need to adjust the charge voltage for my lithium battery?
In many cases, yes. Lithium batteries often require a specific charge voltage, such as 14.6 volts, to charge fully.
Some RV converters allow you to adjust this setting manually using a voltage adjustment screw, which ensures your battery charges properly.
Always check your lithium battery manufacturer’s recommended charge voltage and adjust the converter accordingly.
4. How do I know if my RV converter is compatible with lithium batteries?
Check the product specifications or manual for your converter. Look for terms like “lithium-compatible,” “adjustable voltage,” or specific settings for lithium-ion batteries.
If these features are missing, your RV converter is likely not optimized for lithium use and should be replaced.
5. Can I install a new RV converter myself?
Yes! Most RV converters, including the PowerMax Converter, are designed for straightforward installation.
If you’re comfortable working with basic electrical systems and following safety precautions (like disconnecting power sources), you can likely handle it.
Just take your time, follow step-by-step instructions, and use tools like a multimeter to double-check your work.
6. What tools do I need to install a new RV converter?
Here’s a basic list of tools you may need:
Screwdriver (for mounting and removing covers)
Wire cutters/strippers (for prepping wires)
Multimeter (to check voltage output and connections)
7. How long does it take to replace an RV converter?
For most people, replacing an RV converter takes about 1-2 hours. The exact time depends on your RV’s setup and whether any modifications are needed to fit the new converter.
8. What should I do if my converter doesn’t charge my lithium battery properly?
First, use a multimeter to check the output voltage of the converter. If it’s lower than the required charge voltage (usually around 14.6 volts for lithium batteries), adjust the voltage setting if possible.
If the converter doesn’t allow for adjustments, you may need a different model that supports lithium batteries.
9. Is a lithium compatible converter worth the cost?
Absolutely. While lithium compatible RV converters can be more expensive than traditional models, they protect your investment in lithium batteries by ensuring proper charging.
This extends the lifespan of your batteries and improves overall performance, making the cost worthwhile in the long run.
They’re usually more budget friendly than lithium specific RV converters.
10. What are the signs that my current RV converter needs replacing?
Common signs include:
- Batteries not charging fully or taking too long to charge.
- Electrical systems in your RV underperforming or lights flickering.
- Loud or unusual noises coming from the RV converter.
- Overheating or a noticeable burning smell.
If you notice any of these issues, it’s time to replace your converter, especially if you’ve upgraded to lithium batteries.
Have any more questions? Leave a comment below.
