https://www.ipandee.com/36v-mppt-solar-charge-controller.html A 36 volt solar panel charge controller is a device that is used to regulate the charge of a 36V solar panel battery system. It does this by maximizing the power output of the solar panels and efficiently charging the battery. The MPPT (maximum power point tracking) feature of the controller allows it to optimize the power output of the solar panels by continuously adjusting the solar panel's operating voltage to match the voltage of the battery. This helps to ensure that the battery is charged as efficiently as possible.