Cassette for electrolyzer of a four plate construction

Abstract

A cassette ( 1 ) for an electrolyzer includes two cooling plates ( 2 ) and two electrolyte plates ( 3 a, 3 c), in the form of an anodic electrolyte plate ( 3 a) and a cathodic electrolyte plate ( 3 c). The two cooling plates ( 2 ) contact each other at one surface forming a cooling flow path ( 5 ) between them. Each of the cooling plates ( 2 ) contacts an electrolyte plate ( 3 a, 3 c) at the other, opposite surface and forming an anodic electrolyte flow path ( 6 a) between one of the cooling plates ( 2 ) and the anodic electrolyte plate ( 3 a) and a cathodic electrolyte flow path ( 6 c) between the other cooling plate ( 2 ) and the cathodic electrolyte plate ( 3 c). The electrolyte plates ( 3 a, 3 c) and cooling plates ( 2 ) are each formed with cooling openings ( 7 in, 7 out) for a cooling fluid to pass the plate ( 2, 3 a, 3 c), at least one anodic electrolyte fluid inlet ( 8 in) for an anodic electrolytic fluid to pass the plate ( 2, 3 a, 3 c), at least one cathodic electrolyte fluid inlet ( 9 in) for a cathodic electrolyte fluid to pass the plate ( 2, 3 a, 3 c), at least one anodic gas outlet ( 8 out) for an anodic gas to pass the plate ( 2, 3 a, 3 c), and at least one cathodic gas outlet ( 9 out) for a cathodic gas to pass the plate ( 2, 3 a, 3 c).

What is claimed is: 
     
         1 . A cassette for an electrolyzer, the cassette comprising two cooling plates and two electrolyte plates, in the form of an anodic electrolyte plate and a cathodic electrolyte plate, where the two cooling plates contact each other at one surface forming a cooling flow path between them, and where each of the cooling plates contacts an electrolyte plate at the other, opposite surface and forming an anodic electrolyte flow path between one of the cooling plates and the anodic electrolyte plate and a cathodic electrolyte flow path between the other cooling plate and the cathodic electrolyte plate, and where the electrolyte plates and cooling plates each are formed with cooling openings for a cooling fluid to pass the plate, at least one anodic electrolyte fluid inlet for an anodic electrolytic fluid to pass the plate, at least one cathodic electrolyte fluid inlet for a cathodic electrolyte fluid to pass the plate, at least one anodic gas outlet for an anodic gas to pass the plate, and at least one cathodic gas outlet for a cathodic gas to pass the plate. 
     
     
         2 . The cassette for an electrolyzer according to  claim 1 , wherein the cooling plates and the electrolyte plates in the cassette are connected such that the cooling openings are sealed from the anodic electrolyte flow path and from the cathodic electrolyte flow path, and the cooling openings are in fluid connection to the cooling flow path. 
     
     
         3 . The cassette for an electrolyzer according to  claim 1 , wherein the cooling plates and the electrolyte plates in the cassette are connected such that the anodic electrolyte fluid inlets and the anodic gas outlets are sealed from respectively the cooling flow path and the cathodic electrolyte fluid inlets and the cathodic gas outlets. 
     
     
         4 . The cassette for an electrolyzer according to  claim 1 , wherein the cooling plates and the electrolyte plates in the cassette are connected such that the cathodic electrolyte fluid inlets and the cathodic gas outlets are sealed from respectively the cooling flow path and the anodic electrolyte fluid inlets and the anodic gas outlets. 
     
     
         5 . The cassette for an electrolyzer according to  claim 1 , wherein each of the electrolyte plates defines an active area between the at least one electrolyte fluid inlet and the at least one gas outlet, wherein the active area is formed with openings, and wherein a membrane covers the active area. 
     
     
         6 . The cassette for an electrolyzer according to  claim 5 , further comprising a gasket encircling the active area, and wherein the gasket separates electrolytic fluids within the active area from the gas outlets. 
     
     
         7 . The cassette for an electrolyzer according to  claim 1 , wherein the two cooling plates are contacting each other at their rims. 
     
     
         8 . The cassette for an electrolyzer according to  claim 1 , wherein projections are formed in the cooling plates and/or in the electrolyte plates at a circumference of the cooling openings, at a circumference of the electrolyte fluid inlets and/or at a circumference of the gas outlets, the projections establishing contact to the respective neighbouring plates. 
     
     
         9 . The cassette for an electrolyzer according to  claim 8 , wherein openings are formed in the projections allowing the respective fluids access to the respective flow paths. 
     
     
         10 . The cassette for an electrolyzer according  claim 9 , wherein at least one of the openings is in the form of a recess in a projection formed in one of the plates, ensuring that the projection is not contacting a projection formed in a neighbouring plate. 
     
     
         11 . The cassette for an electrolyzer according to  claim 9 , wherein a recess is formed in both of two connected neighbouring plates. 
     
     
         12 . The cassette for an electrolyzer according to  claim 1 , wherein the anodic gas outlet and the cathodic gas outlet are positioned between a cooling inlet opening and a cooling outlet opening. 
     
     
         13 . The cassette for an electrolyzer according to  claim 1 , wherein each of the plates defines a centre line passing in a length direction of the cassette, and wherein the anodic gas outlet is positioned at a first side of the centre line and the cathodic gas outlet is positioned at a second, opposite side of the centre line. 
     
     
         14 . The cassette for an electrolyzer according to  claim 13 , wherein the anodic gas outlet is positioned at the first side of the centre line substantially halfway between a first side edge of the respective plate and the centre line, and/or the cathodic gas outlet is positioned at the second side of the centre line substantially halfway between a second side edge of the respective plate and the centre line. 
     
     
         15 . The cassette for an electrolyzer according to  claim 2 , wherein the cooling plates and the electrolyte plates in the cassette are connected such that the anodic electrolyte fluid inlets and the anodic gas outlets are sealed from respectively the cooling flow path and the cathodic electrolyte fluid inlets and the cathodic gas outlets. 
     
     
         16 . The cassette for an electrolyzer according to  claim 2 , wherein the cooling plates and the electrolyte plates in the cassette are connected such that the cathodic electrolyte fluid inlets and the cathodic gas outlets are sealed from respectively the cooling flow path and the anodic electrolyte fluid inlets and the anodic gas outlets. 
     
     
         17 . The cassette for an electrolyzer according to  claim 3 , wherein the cooling plates and the electrolyte plates in the cassette are connected such that the cathodic electrolyte fluid inlets and the cathodic gas outlets are sealed from respectively the cooling flow path and the anodic electrolyte fluid inlets and the anodic gas outlets. 
     
     
         18 . The cassette for an electrolyzer according to  claim 2 , wherein each of the electrolyte plates defines an active area between the at least one electrolyte fluid inlet and the at least one gas outlet, wherein the active area is formed with openings, and wherein a membrane covers the active area. 
     
     
         19 . The cassette for an electrolyzer according to  claim 3 , wherein each of the electrolyte plates defines an active area between the at least one electrolyte fluid inlet and the at least one gas outlet, wherein the active area is formed with openings, and wherein a membrane covers the active area. 
     
     
         20 . The cassette for an electrolyzer according to  claim 4 , wherein each of the electrolyte plates defines an active area between the at least one electrolyte fluid inlet and the at least one gas outlet, wherein the active area is formed with openings, and wherein a membrane covers the active area.