Sun Energise 20W 12V Solar Powered Battery Charger & Maintainer, Built-in Smart MPPT Charge Controller, Waterproof 20 Watt 12 Volt Solar Panel Trickle Charging Kits for Car Auto Boat RV Marine Trailer

It has worked great! It has kept my battery good and it was always charged when i needed it!

This is my second solar panel battery maintainer that I have bought from this company. I was happy with the first one and this one is even better.There are two great things with this new panel.One, on the collector panel itself, there is a little light that indicates when the panel is receiving and generating solar electricity or not working properly… Super handy.Two, this panel has a great advantage in that I can be put up to a window, and it will generate electricity. It does not need to be mounted outside the car. The big benefit is that it is inside the car and when I lock the car the panel is safe and secure. Anyone that uses the panel can just put it on the dash or in the rear window. I put my panel in a tinted window that faces south and even though the window is coated with a sunscreen It still produces enough electricity to maintain the battery.I have included a picture taken from the outside of the car showing the panel through the tinted window which is coated with solar film. The panel is on the inside of the car where it is collecting sun and working great.Thanks for the great product. I am very happy.

Seems like a good idea. I think it works well if there isn’t a load on your battery and it just needs topping off. I tried using this in an RV setting. When the battery was fully charged it did well. However, if cell phone chargers dropped the voltage to at or below 9 volts it quit working. It would just flash like it wasn’t getting good sun.However, start up the vehicle and all of sudden without moving it then it said the sun was good and it was working.I tried putting on the dash and inside the vehicle. It warped in about a week. Not sure why, other plastic things on the dash right next to it didn’t have this problem.I tried placing on the roof of the vehicle with the generous cord size. Strangely, it didn’t improve performance. If the battery is fully charged then it on green steady and shows working. But if your battery drops low which is when you need it the most, it quits working and just blinks green.It probably very useful in other applications.----------Edit support reached out to me and replaced the unit and helped me understand how to use it. It will keep a battery topped off. It isn't designed to keep up with a 3.2 amp charger. Works as intended.

Product is sturdy and works as described !

This is exactly what we needed to keep the battery charged on our dumper trailer. Made it easy to mount to a toolbox and convert the sun energy to free electricity.