Alkaline water electrolysis apparatus

Abstract

An alkaline water electrolysis apparatus includes: a separation membrane including a first main surface and a second main surface opposite to the first main surface; a first electrode including a third main surface and a fourth main surface opposite to the third main surface, the third main surface being provided to face the first main surface of the separation membrane; and a first bipolar plate including a fifth main surface, the fifth main surface being provided in contact with the fourth main surface of the first electrode, wherein the first electrode consists of a first metal porous body having a three-dimensional mesh structure.

1 . An alkaline water electrolysis apparatus comprising:
 a separation membrane including a first main surface and a second main surface opposite to the first main surface;   a first electrode including a third main surface and a fourth main surface opposite to the third main surface, the third main surface being provided to face the first main surface of the separation membrane; and   a first bipolar plate including a fifth main surface, the fifth main surface being provided in contact with the fourth main surface of the first electrode, wherein   the first electrode consists of a first metal porous body having a three-dimensional mesh structure.   
     
     
         2 . The alkaline water electrolysis apparatus according to  claim 1 , comprising:
 a second electrode including a sixth main surface and a seventh main surface opposite to the sixth main surface, the sixth main surface being provided to face the second main surface of the separation membrane; and   a second bipolar plate including an eighth main surface, the eighth main surface being provided in contact with the seventh main surface of the second electrode, wherein   the second electrode consists of a second metal porous body having a three-dimensional mesh structure.   
     
     
         3 . The alkaline water electrolysis apparatus according to  claim 1 , wherein
 the third main surface of the first electrode is in a form of a square of 1 cm×1 cm, constant current electrolysis is performed for 100 seconds at a current of 1.5 A under a condition that a gas pressure is 0.1 MPa and a flow velocity of a potassium hydroxide aqueous solution is 1 m/minute or 10 m/minute so as to obtain potential oscillation data per ms, a result of performing Fourier transform onto data obtained by multiplying the potential oscillation data by a window function is indicated in a coordinate system having an X axis representing a frequency and a Y axis representing an amplitude, and a first frequency spectrum is a frequency spectrum at the flow velocity of 1 m/minute and a second frequency spectrum is a frequency spectrum at the flow velocity of 10 m/minute,   the first frequency spectrum has a maximum peak in a range of a frequency of 0.2 Hz or more and a frequency of 10 Hz or less,   a frequency at an amplitude P1 of the maximum peak is F1 in the first frequency spectrum, and   a ratio P2/P1 of an amplitude P2 of the second frequency spectrum at the frequency F1 to the amplitude P1 is 0.5 or less.   
     
     
         4 . The alkaline water electrolysis apparatus according to  claim 2 , wherein
 the sixth main surface of the second electrode is in a form of a square of 1 cm×1 cm, constant current electrolysis is performed for 100 seconds at a current of 1.5 A under a condition that a gas pressure is 0.1 MPa and a flow velocity of a potassium hydroxide aqueous solution is 1 m/minute or 10 m/minute so as to obtain potential oscillation data per ms, a result of performing Fourier transform onto data obtained by multiplying the potential oscillation data by a window function is indicated in a coordinate system having an X axis representing a frequency and a Y axis representing an amplitude, and a third frequency spectrum is a frequency spectrum at the flow velocity of 1 m/minute and a fourth frequency spectrum is a frequency spectrum at the flow velocity of 10 m/minute,   the third frequency spectrum has a maximum peak in a range of a frequency of 0.2 Hz or more and a frequency of 10 Hz or less,   a frequency at an amplitude P3 of the maximum peak is F3 in the third frequency spectrum, and   a ratio P4/P3 of an amplitude P4 of the fourth frequency spectrum at the frequency F3 to the amplitude P3 is 0.5 or less.