PWM Solar Charge Controller 20A Solar Panel Controller 12V/24V Auto Adjustable LCD Display Solar Panel Battery Regulator with USB Port

Works as it should! Easy to use, and have an easy to read display.

It was inexpensive. It claims it can work on lithium battery type. It does have adjustable voltage limits , however The Voltage measurement was way off, it would have damaged batteries if used as is. I was able to identify the resistors making the voltage divider internally on the board and modify them to fix voltage accuracy. It Shows only voltage, not charge currents. Switching is all done on the negative side with positive all bussed together internal between solar, battery and load. This limits what can be the load, as it’s common negative terminal must route to the controller. Back thin metal cover is a heat sink, but just slightly presses against internal fets with no proper mounting and poor thermal contact area. I modified my unit to have a real heat sink plate and better thermal transfer. Unless you have the engineering knowledge and time to fix this unit up, I suggest looking at a higher quality unit.