















🔌 Power your adventures smarter, safer, and greener with Renogy’s 40A DC-DC charger!
The Renogy 12V 40A DC to DC Battery Charger with MPPT is a versatile, compact power solution designed for RVs, cars, boats, and off-grid setups. It features dual charging modes that automatically switch between DC input and solar power, maximizing efficiency. Compatible with LiFePO4, Gel, Flooded, and Sealed Lead Acid batteries, it uses adaptive 4-stage charging logic to optimize battery health. Comprehensive protections guard against electrical faults and temperature extremes, while intuitive controls and LED indicators simplify operation. Certified to global safety standards and built for rugged environments, this charger ensures reliable, hassle-free power management wherever your journey takes you.










| ASIN | B0DF2XXML8 |
| Best Sellers Rank | 407,821 in Automotive ( See Top 100 in Automotive ) 1,501 in Car Battery Charging Units |
| Customer Reviews | 4.2 4.2 out of 5 stars (481) |
| Date First Available | 27 Jun. 2025 |
| Item model number | RBC40D1S |
| Manufacturer | Renogy |
| Part number | RBC40D1S |
| Power source type | dc |
| Product Dimensions | 4.8 x 19.51 x 14.91 cm; 1.28 kg |
J**N
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.
J**U
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.
S**G
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.
A**X
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!
B**T
Looks good quality but haven't installed it yet.
Trustpilot
1 day ago
2 days ago