Yes, usually the controller will function to control the process of charging and discharging. When the voltage is higher than the maintenance voltage, the controller will cut down on the charging of the battery. And when the voltage is lower than the protection voltage, the controller will stop the battery from discharging. Besides, it can also prevent overload and short circuits to protect the circuit. The controller is where you can set the working time of the street lights and how bright they should be.
More reading: Solar Street Light Battery: What to Know And How to Choose
