NOVELTY - Water electrolysis device comprises an electrolytic cell stack (12) in core, hydro-thermal management process component, gas and management process component. The hydro-thermal management process component comprises water tank (2), circulation water pump (6), high pressure water pump (3), two-way electromagnetic valve (7), former and latter water purification device and heat exchanger. The gas and separate management process comprises anode water separator, cathode water separator, former and latter one-way valve, hydrogen storage tank and oxygen storage tank.    USE - Water electrolysis device used in semiconductor industry for preparing silicon.    ADVANTAGE - The water electrolysis device is simple, and has high efficiency.    DETAILED DESCRIPTION - Water electrolysis device comprises an electrolytic cell stack in core, hydro-thermal management process component, gas and management process component. The hydro-thermal management process component comprises water tank, circulation water pump, high pressure water pump, two-way electromagnetic valve, former and latter water purification device and heat exchanger. The gas and separate management process comprises anode water separator, cathode water separator, former and latter one-way valve, hydrogen storage tank and oxygen storage tank. The electrolytic cell stack is connected with the anode water inlet through a pipeline and the circulation water pump and former water purification device is connected with bottom of the anode water separator. Gas entrance is connected with the electrolytic cell stack, cathode water exit pipe and water entrance through a cathode water separator that is connected with the gas exit of the anode water separator through a latter one-way valve. The latter one-way valve is connected with the oxygen storage tank, which is connected with the water tank through the pipeline. The high pressure water pump and the anode water separator or bottom of the water outlet is connected with the cathode water separator and bottom of the two-way electromagnetic valve. The latter water purification device is connected with the water tank that is connected with the gas exit of the cathode water separator through the former one-way valve. The former one-way valve is connected with the hydrogen storage tank.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a water electrolysis device.    Water tank (2)    High pressure water pump (3)    Circulation water pump (6)    Two-way electromagnetic valve (7)    Electrolytic cell stack (12)