Container valve, fire extinguishing device and battery cabinet

The invention relates to a container valve, a fire extinguishing device and a battery cabinet. The container valve comprises a valve body and a piston, wherein the piston comprises a body, an air supply core and an elastic part. When the fire extinguishing device is in an initial state, the air supply core is balanced and is in a closed position under the action of the pressure in an inhibitor bottle and a fire trace tube and the acting force of the elastic part. When the pressure in the fire trace tube is slightly leaked and the pressure of an inlet cavity is greater than a first pressure value of the pressure of an outlet cavity but smaller than a second pressure value, the whole piston is kept still, and the air supply core moves towards the outlet cavity to an air supply position under the action of differential pressure. At the moment, the outlet cavity communicates with the inlet cavity, so that the pressure in the inhibitor bottle is supplemented into the fire trace tube, and the pressure of the outlet