40A DC-DC Battery Charger with MPPT Solar and Alternator Dual Power Input, for Flooded, Gel, AGM, and Lithium Battery

5 stars because was refunded..

Seemed fine to start with, charge via car or solar, it gets very hot. I used a fan to keep it at a better temperature. but it just stopped working after nearly 2 months. Was still lit up but no power via car or solar. Tried to contact renogy, never got an answer to call or emails, it was past it returns date on Amazon, so wouldn’t let me send it back. I contacted Amazon but luckily it was on the monthly payment, so they just let me send it back. Got a refund on the payments I had made.

Well when looking for the PERFECT. EVERYTHING CHARGER this ticked all the boxes as it.did solar 40a batt batt for.my 300w lithium battrey the one must have was a way to monitor solar and b2b as shore power was never going to happen after meticulous research on the advert it clearly states add renologys bt2 bluetooth dongle via rj connector and the magic will happen well on arrival I paid my auto electrician to fit it got it home and went to plug in the magic box and guess what NO MAGIC HARRY POTTER HAS LEFT THE BUILDING as it has no port to plug in to on repetedly contacting reneolgy to rectify it nope no response so it's not what was described at this point I'm out the instalation cost and hassle and time if I rip it out instead of joy just gutted

Be aware that many of the reviews here are for a different product. This is a newer product that is cheaper and more compact but does not allow the Bluetooth connection. There is no way to see what is happening with the solar or charging currents etc other than the LED status. Works well as a fit and forget but not as good for those interested in monitoring numbers etc.

this charger has failed after two weeks and about three days, I was 3 days into my holiday when I noticed that my voltage had dropped on my lithium 100ah battery, when I checked the dc to dc charger it was not working, not sure when it failed, Now the problem I have is not with the dc to dc charger failing but with the customer service that renogy provide, as other reviews have said it is abismal at best, they want me to do all the testing on the battery I have, the charger, they want video proof of everything and wont accept a return for testing even though I said I would pay for sending and return to me, apparently they dont test them in the UK, so sending back is not happening, the warranty was two years I believe, I have had this since 16 January 2025 and they wont do anythig but keep asking me for more testing and videos of testing.apparently this how the company does warranty claims.You have to prove its not working by testing and videoing everything they ask for.Think twice before buying anything from renogy as if it fails you will get nowhere with customer service or technical for a long time if ever.

Broken after 2 months, just be carful as my installer has said this is common with Renogy products

Le chargeur n'est pas compatible avec le boîtier Bluetooth Renogy bt-2, car il n'y a pas de port de communications comme indiqué dans la description