Elastic Current Distributor for Percolating Cells

Abstract

An electrolysis cell comprising an anodic compartment and a cathodic compartment separated by an ion-exchange membrane, at least one of said compartments equipped with a gas-diffusion electrode having two major surfaces, the first major surface of said gas-diffusion electrode facing the membrane and being in contact with a planar porous element to be traversed by an electrode flow, the second major surface of said gas-diffusion electrode being in contact with a current distributor comprising a multiplicity of elastic conductive protrusions for compressing said gas-diffusion electrode against said planar porous element.

1 . An electrolysis cell comprising an anodic compartment and a cathodic compartment separated by an ion-exchange membrane, at least one of said compartments equipped with a gas-diffusion electrode having two major surfaces, the first major surface of said gas-diffusion electrode facing the membrane and being in contact with a planar porous element to be traversed by an electrode flow, the second major surface of said gas-diffusion electrode being in contact with a current distributor comprising a multiplicity of elastic conductive protrusions for compressing said gas-diffusion electrode against said planar porous element. 
     
     
         2 . The cell of  claim 1  wherein said multiplicity of conductive protrusions exerts a pressure of 0.1 to 0.5 kg/cm 2  on the gas-diffusion electrode. 
     
     
         3 . The cell of  claim 1  wherein said current distributor comprising said multiplicity of conductive protrusions is obtained by cutting and shaping of a metal sheet. 
     
     
         4 . The cell of  claim 3  wherein said conductive protrusions are spring tags arranged according to a comb-like geometry. 
     
     
         5 . The cell of  claim 4  wherein said spring tags are arranged in adjacent pairs and the spring tags of each of said pairs protrude in opposite directions from the major place of said metal sheet. 
     
     
         6 . The cell of  claim 3  wherein said conductive protrusions are optionally quadrangular individual tiles comprising a multiplicity of spring tags and at least one opening for gas circulation. 
     
     
         7 . The cell of  claim 6  wherein said tiles are welded to a rigid current collector in optionally off-set parallel rows. 
     
     
         8 . The cell of  claim 3  wherein said metal sheet has a thickness of 0.5 to 1.5 millimeters. 
     
     
         9 . The cell of  claim 3  wherein said metal sheet is a punched sheet. 
     
     
         10 . The cell of  claim 3  wherein said metal sheet is made of nickel. 
     
     
         11 . The cell of  claim 10  wherein said nickel sheet is provided with a coating for reducing the electric contact resistance in correspondence of said protrusions. 
     
     
         12 . The cell of  claim 1  comprising an additional element for distributing the mechanical compression force selected from the group of meshes, punched sheets and expanded sheets inserted between said current distributor and said gas-diffusion electrode.