The Solar Led Street Lamps panel will charge the battery during the day, and the charging voltage will continue to discharge only when it is charged to 24V. The main purpose of this arrangement is to prevent the battery from being damaged by deep discharge at regular intervals. In the case of battery undervoltage, if the solar street light controller is not restarted, between 22.2 volts and 24 volts are undervoltage. Only when the battery voltage of the High Quality Solar Light is charged to more than 24 volts will it continue to discharge. Please contact us for more information about this High Quality Solar Led Street Light.