Renogy 12V 50A DC to DC Battery Charger with MPPT, On-Board Battery for Gel, AGM, Flooded and Lithium Batteries, Using Multi-Stage Charging, Solar Panel and Alternator

I upgraded my solar panel with the shade tech panel. Then found out I needed to upgrade to this 50amp dc/dc charger from my 30 amp This works well and keeps the batteries top off. If I read the instructions correctly it even charges my automotive start battery if it gets run down.

I upgraded my 2003 Sportsmobile with a 300AHr lithium battery and needed a dc/dc converter, this one did the job. I'm very happy with Renogy products, everything works awesome now!

updated 2025. New app updates to the Bluetooth module have not solved the problem. You can not connect to this charger using Bluetooth alone the app requires a working internet connection to revalidate your login every so often. Which means this product is unusable for people camping offgrid. Pros: None Cons: Huge Inefficient compared to inexpensive MPPT setups No Battery nor charging status Bluetooth module does not work offgird I got this to replace my MPPT 15Amp charger. The Renogy setup is significantly worse. My old charger could run my fridge indefinitely with the same 110W panel. With the Renogy I am out of power sometime while I sleep. This thing is huge. It’s like 4 times larger than a similar MPPT system. There is no screen or way to see the charging rate and battery status. I bought Renogy’a external display but it does not give enough detail. So I also bought their Bluetooth module. The Bluetooth module plus app give amazing detail but only work with a recent internet connection. The docs say you can login to the app and then use it offline with Bluetooth, but this is a lie. Do NOT expect that to work. The app re validates the login token. I just tried it after a few months of not using the app and it gave me an auth token error and said I needed to login. Dealbreaker! I do NOT recommend.

I got this for my van build. The sun doesn't always shine but the wheels keep a-turning! I would highly recommend this thing if you're built right for it. MAKE SURE YOUR ALTERNATOR CAN HANDLE THE EXTRA LOAD!!!! Aftermarket high output alternators highly recommended. This unit reliably pulls 48 to 50 amp and up to 700 w when it's really cranking. BE SURE YOU HAVE THE RIGHT FUSES AND OVERSIZED WIRE! If you disregard my warnings you stand the real risk of killing your alt and possibly burning yourself to the ground. It's a lot of juice. Handle it with respect. Do your math and your homework. Also keep in mind that a ton of heat is being generated at the charger. Make sure you have plenty of ventilation to dispell the excess heat and I would advise putting a couple cheap thermostat controlled laptop fans on it. They're like 6 dollars. This will help preserve the charger and prevent excessive heat build up in your cabinet. I actually put a large laptop fan in the air intake opening I put on my cabinet and another to exhaust the heat from the box. Otherwise It's very easy to hook up and required nothing special to hook up and fire up. Worth every cent. Just don't wing it , ok? It's not cheap and messing with this stuff without the right information and prep could cost you dearly.

I have run through a dozen different products from Renogy, and I think this is a my favorite. In use for several months at the time of this updated review. Most people will need the bluetooth module for configuration. Because the charging amps are configurable (In 10A increments) this is the perfect product for a boat with an outboard. I have mine set to charge at 20A, and it does a great job detecting when the outboard is running and charging my LiFE4Po bank. It also works great with solar. The way this device works and is wired saves a lot of room, wiring, and complexity on any boat/RV. One major complaint: The PV Voltage is ridiculously low. I upgraded from a 200w panel with a really low PV voltage, which worked fine, to a 300w panel with a normal 36V PV Voltage and now I have to upgrade. It's not clear if the 50A version actually has a higher rating, there is a lot of conflicting information. Two minor complaints: 1) I wish the charging amps were configurable to an exact number or at least 5 amp increments. For some small outboards on boats even 10 amps is going to be too much. 2) I wish there were a way to keep the device from turning on from incoming solar. I don't think this is a feature on any other solar charge controller, but it is annoying to have to install a breaker or switch just to keep the unit from turning on every time the sun is out.

I rarely leave reviews and in most cases only when I am really annoyed by a product. But this unit is really great at a very resonable price! Works very well, is compact, and has many great features that only a combined dual (solar and alternator) charger can provide. For example charging my starter battery when the solar battery is full. I think I had a small parasitic drain on the van which caused the battery to be empty after a few weeks of not driving. With the renogy charger that is no longer a problem. And of course the main function to support dual charging is also great. I specifically used the smaller version (30A) to limit stress on the alternator . That is probably the only missing feature I can think of: configure the max draw from the alternator in the app. But with the 30A version that is not really a problem. And I anyway only have 400W of solar, so 30A is fine.

I actually haven’t fired this controller up yet but wanted to clarify this unit doesn’t need a BT-2 unit as many reviewers suggest. Here is response from Renogy service: Based on the provided information for the RBC40D1S charger, the unit has a built-in Bluetooth communication function. This means you can connect directly to the Renogy DC Home or Core app via Bluetooth to monitor and adjust settings; an external BT-2 module is not required for this model. Since the RBC40D1S has integrated Bluetooth, the BT-2 module is typically used for Renogy products that do not have built-in Bluetooth. It is possible that the BT-2 is not compatible with your specific charger model.

I have a cargo trailer that I use for work with a 2000 watt inverter to run power tool chargers & lights in the trailer. I have a 200 watt solar array connected to the solar input as well as the vehicle smart alternator input. The (2) 100 Ah AGM batteries stay charged through this device to where I never have to plug in my trailer to the house to charge my batteries. What I like about this product is if it’s cloudy and I’m using power then the vehicle will charge the batteries as I’m driving from job to job or I can start the truck for a few minutes and get a charge. This device also prevents voltage feeding back to the vehicle from my trailer batteries as it would if it were connected straight to the battery output from the truck. It also prevents overcharging of the batteries, extending the life. Lastly, the ability to change battery types on this device makes it great to use for different battery chemical types. The price is a little high but it does exactly what I need in just one device.

Other than a issue with a TAX invoice as in they do not supply one a major pain In Australia if you want to claim the unit as a Business expense as is what i wanted to do. The unit is by far the best one i have tested so far. It does not just charge and cut off it also supplies power to the connected devices so as not to run the battery down when the battery is full and the sun is still shinning. So if you don't need to right this off TAX wise i would recommend it. So 5 stars for the Item 1 start for the seller.

Installed in a bus conversion to take advantage of the alternator charging my LiFePo4 batteries when the engine is running and being able to trickle charge the starter batteries while parked. Seamless installation, robust connectors and after I ordered and installed the BT-2 hardware, the app provides all the pertinent information in real time. Time will determine the durability of the device, but it's working great thus far. Cheers!

Super easy to install and charges really well. Renogy make incredibly well build products and I would highly recommend. It allows us to run the fridge when travelling in our trailer on battery power without running down the battery. You do need to ensure you run the correct wire gauge for the length of your run from your vehicle battery to the charger. I would also recommend to get the appropriate circuit breakers for safety.

I've had this wired up in my vehicle for a few months and it's doing a great job. I've regularly seen it pushing over 40A through the battery. 45 minutes driving a day is enough to keep my fridge running 24/7. Knowing how fast I can charge the battery I wish I'd bought a smaller one!

Looks good quality but haven't installed it yet.