The invention relates to a storage battery emergency power supply system and method and a railway vehicle. The storage battery emergency power supply system comprises multiple traction converters, multiple two-way auxiliary converters, multiple battery chargers and multiple storage batteries. Under the emergency working condition, the storage batteries provide emergency direct current for a directcurrent through line of the whole vehicle, and a traction motor and an air conditioning system are supplied with power through the battery chargers, the two-way auxiliary converters and the tractionconverters; meanwhile, at least one contactor TBK is arranged on an alternating current through line, under the emergency working condition, the contactors TBK are switched off to separate the alternating current through line into multiple sections, and each section is separately controlled. According to the system and method, it is guaranteed that the vehicle can be driven out of a fault area when pantograph-catenary faults occur; meanwhile, it is guaranteed that the air conditioning system works normally, and a comfortable environment is provided for passengers.