ECO-WORTHY 25W 12V Solar Battery Charger Trickle Maintainer, 25W Waterproof Solar Panel Kit + Adjustable Mount Bracket + Upgrade Controller,for 12V Batteries Cars RV Boat Motorcycle Marine

Great little solar panel and controller
This was added to a electric troll motor battery box. It works wall and keeps the battery charging throughout the day and when not in use. It’s not the fastest charge, but over time, it does help keep things going.

Great solar kit, but cheap wires. NOT waterproof
The solar panel and the charge controller itself work great. The wires are junk, wasting 10-20% of the total solar power and causing charging issues. The charge controller is not waterproof or even water resistant, and it takes patience to attach wires to the green connector. Otherwise, the charger works well. Rather than return it, I fixed these problems for about 15 dollars.Actual specs:I measured this unit putting 1.4 amps into my low car battery on a sunny day in December in Maine. That’s about 18 watts in the middle of winter, pretty good for a 20 watt panel. That was before I fixed the wiring.The label on the back of the solar panel has slightly different specs than the Amazon title. It says 25 watts max power. See attached photo.Charge controller:The included charge controller works well. It’s an intelligent 3A PWM charger that automatically switches through 3 charging phases: bulk, absorption, float (trickle). It has an LED to indicate when it has solar power and what charging phase it’s in. It will prevent over discharging below 10.8 volts and over charging above 14.4 volts.At one point I thought my charger was broken and started looking for a replacement. A decent PWM charger like this runs 15-20, so it’s a decent value. I later discovered the charger was fine, the problem was the cheap included wires (see below).I was a little worried about the charger consuming battery power when there isn’t any sun. Cheaper chargers use a little battery power overnight and on very cloudy days while waiting for the sun to come back. I wanted to leave my system unattended for months during our short and cloudy winter days without discharging my battery, so I can’t tolerate much current drain when the sun is gone. Amazon didn’t list the current drain when I bought it. I measured the charger’s current drain with no sun at about 1mA. That seems pretty reasonable compared to 10-50mA with other chargers. The charger ships with a spec sheet, which lists the current drain as 1.5mA (see attached).The spec sheet says the charger is made for Gel batteries. It seems to work fine on my SUV car battery though.Cheap wires:I measured my battery voltage while charging on a sunny day. 13-14 volts is normal, but I was only getting 12.4 volts. I thought the controller had gone bad so I tried another one. Same problem. I tried lots of things, went over all the connections many many times but nothing worked. It definitely had power coming from the solar panel, it just wasn’t getting to the battery. Over a few days I did notice the battery charge increasing very slowly, but the charger kept thinking the battery was fully charged too soon and kept turning off (trickle mode) too early. I finally had the idea to check the battery voltage at the other end of the battery wires (where they connect to the charger). The charger was putting out 13.6 volts at about 1.5 amps, but only 12.4 volts was getting to the battery. That’s 10% of the solar power being wasted by wire resistance! It was also enough to fool the charger into thinking the battery was charged and switching to a low power mode, which throws away even more of the generated power. It will still charge your battery eventually assuming you aren’t using the battery for something else, but it will be slow.I replaced all the wire with normal 16 gauge wire, and it fixed everything. I measured 13.6 volts at the charger and 13.5 volts at the battery while charging at 1.5 amps. It charges much faster now, and I can use the battery to power other things. I attached a picture of the cheap wires they include and some normal 16AWG wires I replaced them with. On the outside it’s deceiving because the cheap wires look reasonably thick. But if you cut into it you’ll see the cheap wires are almost all rubber insulation and have very little actual metal inside.Replacement wire: https://www.amazon.com/dp/B00NSGCVWI/ref=cm_sw_r_cp_awdb_feSyyb487STEMWaterproofing:The actual solar panel appears waterproof and has white silicone around the edges on the back. However the charger is definitely NOT waterproof. It came with clear silicone applied along the bottom of the green connector, but that’s pointless since the top and sides of the connector have bigger openings and were left unsealed. I needed the charger to work outside in the winter in rain, snow, ice, etc., so any water intrusion could easily freeze and damage things. You could always buy silicone and seal all the openings including the holes in the green connector where the wires attach, but then it will be a pain if you ever want to remove and reattach the wires later. I ended up opening the charger box and spraying conformal coat to waterproof all the electronics. Then I drilled a 1/8″ hole in the white box to allow any water that gets in to drain back out. Takes about 10 minutes. So far it’s holding up well to our Maine winter environment!Conformal coat: https://www.amazon.com/dp/B00BXSMNWG/ref=cm_sw_r_cp_awdb_AbSyybQ2NH5G4I didn’t see any of this information posted anywhere else, so hopefully some people will find this info helpful!

Great camping item.
Great item for certain applications, I got it to help keep my tractor charged… It can help but usually only in the summer time when there’s not a lot of clouds.

This appears to be good quality for the price. Very satisfying after plugging it in to see the included controller light up and start charging. I bought for a private aircraft to keep the expensive $800 aircraft battery topped up during the cold weather. It does recommend not placing it behind a window however I placed it flat on the dashboard in the windshield and it seems to work fine, maybe not optimal but it was charging and I don’t have to worry about it being damaged in wind etc as it will be unattended in my case. The included alligator and permanent battery connections are a plus as are the cable lengths which were more that adequate for my use.I would recommend and if I have any issues – will update

bought this in 2019, £40, now its shot up in price.im running a 12v pond pump with this, it works very well.