12V 40A DC to DC Battery Charger with Solar Input MPPT, Compatible with LiFePO4, Gel, Flooded, and Sealed Lead Acid Batteries, Two Charging Options for RV, Car, Camping, Marine

I researched for probably three months on what DC to DC charger I was gonna get. This one was highly recommended by everyone. As well as offering solar charging and coming from a reputable brand I know I can trust. I’ve been using it for about a month already and it’s worked awesome. I don’t think it’s possible to find a better deal especially for high-quality name and product like this one.

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.

Everything is perfect except that I bought the BT-2 and surprisingly this model 40 amps dosnt support Rj25 so u can't use the BT-2 that's why I'm giving it a 3 star

I have not used it yet, it will probably be another month before I use it so look for an update in like feb to april. The device looks solid it is an aluminum case. The description says BT-2 sold separately but there is no where to connect the BT-2 device. The wiring appears solid, the 8AWG wire is EXTREAMLY fine stranded I would say at least 200 strand. It states 200C but even if you rate it at 105C 8 AWG is good for 76 A, well above the 40A rating. I hope it lasts as the outside and accessible wiring looks very good. So far only CON is the description being misleading causing me to buy a BT-2 for no reason.

for what i paid expected it to be better engineered. cables are way too thin. for 40amps you'd need 6 gauge or 4, for longer runs. solar charging is nice.