The invention discloses an 
electric motor coach storage battery 
protection system and a method thereof, an auxiliary power supply provides a working power supply for a 
system voltage sampling circuit and maintains a power supply for a processor in a deep dormant state, and a main power supply is controlled by a main power supply 
control circuit and provides a working power supply for the 
system during normal work. A charging 
control circuit is respectively connected with the processor and a charger, the charger is connected with an automobile storage battery, the 
voltage sampling circuit is connected with the automobile storage battery and the processor, and by automatically detecting the 
voltage value of the automobile storage battery, when the voltage is reduced to be required to charge the automobile storage battery, the 
system is automatically connected with the vehicle-mounted DC / DC charger to charge the automobile storage battery; the voltage of the current battery is monitored in real time, and when the battery is fully charged and the voltage rises to a set voltage value, the system disconnects the charger and enters a deep 
sleep mode, and when the voltage of the storage battery drops again and needs to be charged, an external sampling circuit provides a trigger 
signal to wake up the system and charge the storage battery again.