SOLPERK Solar Panel Kit 20W 12V, Solar Battery Trickle Charger Maintainer + Upgrade Controller + Adjustable Mount Bracket for Boat Car RV Motorcycle Marine Automotive

I was skeptical when I made the purchase, Now.. I'm impressed. I played with it a bit connecting it to a new battery to top it off which it did in about 30min. Another battery 970cca that had been drained to 12.1v and it topped it off to 13.2v in about 2.75 hrs. The other day had it connected to a 12AH DS battery and we got snow. After accumulating about an inch of snow on the panel it was still charging, certainly at a reduced rate but charging. On a bright day I put the panel out of direct sunlight and it still topped off the battery after several hours. It definitely performs better than I would have expected. It seems the panel and charge controller it is packaged with are a good match.It is very easy to work with, basically plug and play. It is pretty compact and the indicators are simple and easy to read. A good buy in my opinion.

Solidly built. Works well. It keeps a 24V heavy truck charged. It was just sitting on the cab of the truck when strong wind gusts blew it off. It survived and is still in service. We've now bought three of these. The second is on a 12V truck, and the third is on a 12V trailer.

Works well and easy to set upVery well madeYes I would order againGreat Price

Fantastic! I mounted the panel outside, ran the wire inside to the controller which I plugged into a relatively new 12v AGM car battery. The panel charged the battery up the first day and keeps it topped-off enough for the battery's current load, which is currently a 12v automotive LED that I mounted pointing at the ceiling of the kitchen. Makes a great night light in there that can run all night, every night. The plan is to set up the whole house with night lights in strategic areas so as not to need to use grid power to get around the house at night. Also plan to make a simple photosensitive on/off circuit so the system will be 100% maintenance free if desired. Great panel! Highly recommend. I'll be getting another to hook up to my car to keep its battery charged also. GO SOLAR!!!

Seems well built. Used for battery maintainer for a boat and dump trailer.

OUTSTANDING!! Bought a battery with a 6 month warranty from Autozone in August of '23. Battery finally gave out in November of 2024. Decided to see how well this thing would work. Battery was completely drained, added water to the empty cells and hooked everything up. Very simple hookups. After 1 day, got 9v on the battery guage. I decided to wait a few extra days and see if it would actually take a 5 month old dead battery to 13.3v. Fired right up. Was not expecting the outcome. Very impressed.

Very good ...i use it to keep the battery changed on my 14 foot dump trailer . works great

First off, I never intended to use just one of these panels to charge my 12V lead acid car battery with the included PWM charge controller and attached wiring harness. Rather, I intend to buy multiple examples of these panels and configure them with a more comprehensive MPPT controller, LiFePO4 battery and inverter in a carry-in-car and set-up-quickly portable application. The 23.1" (541mm) square footprint is ideal for the portability I need and the price is certainly right.Fortunately, the fit and finish of the panel itself is very good. This sort of thing would have easily cost twice as much just a few short years ago. There are a few rough edges on the corners of the aluminum framing, but that's a minor point. The individual cells look to be very cleanly assembled, topped with a nice piece of glass and the caulking sealant job along the interior of the frame is very clean.I knew from the Amazon listing, however, that the panel would come with a 6' long piece of spindly zip cord terminated with a 2-pin trailer connector. The good news is that the junction box termination on the back of the panel is of the conventional type with a water-proof seal. It's going to be relatively easy to solder in better cabling with standard MC-4 connectors.As it turns out, the attached cable (basically 14 gauge red/black lamp cord) had a short . . . zero voltage and amp readings on the multimeter at the connector end! Readings off the tabs inside the junction box (easy to pry off the back cover with a flat blade screwdriver) indicates, though, that the panel outputs 23.6V and 2.5A on my quickly-assembled back yard test rig (picture attached.) That's very good. I tested at Noon with reasonably perpendicular panel/Sun angling on a cloudless day. Ambient temperature was approximately 70° F / 21° CNext, I trimmed/stripped the 14 gauge wires to within about 1 foot of the junction box and got similarly good readings. Subsequently, I found out that the short was in the remaining (now detached) ~5 feet of cable somewhere along the black/negative wire. I did not test the included PWM charge controller.If it was just for the panel itself, I'd give the Solperk SK-M50W a solid 5 stars. I'm knocking it down to 4 stars because the wiring harness is terrible and, in my case, non-functioning out of the box. I will be buying more of these panels for my above-described application, knowing that the other included bits will be going into the waste can and I'll need to solder in suitable 10 gauge wires at the junction box end, terminated at the other end with real MC-4 connectors. The additional attached photo here shows the back of the panel (junction box cover removed) with labeling. In case the resolution of the photo isn't good enough to clearly see, the specifications shown on the label are as follows . . .Solperk Model: SK-M50W solar panelMaximum Power (Pmax) 50WMaximum Power Voltage (Vmp) 18VMaximum Power Current (Imp) 2.78AOpen Circuit Voltage (Voc) 21.6VShort Circuit Current (Isc) 3.06AMaximum System Voltage 600VDCNominal Operating Cell Temp. (NOCT) 45+/-2°CPower Tolerance +/-5%Application Class Class AWeight 7.2lbsDimensions 21.3 x 21.3 x 1 inchAll technical data at Standard Test Condition (STC).STC Irradiance 1000W/m2. Cell Temperature 25°C. Air Mass AM=1.5