Separator plate, and die pair and method for producing such a separator plate

Abstract

A separator plate for an electrolyser, to a method for producing same, and to a die pair for producing such a separator plate and for carrying out said method. A separator plate for an electrolyser, having a first metal layer, the separator plate comprising an active region having at least one multitude of flow channels for a reaction medium. The flow channels being embossed into the first metal layer and having a channel bottom and channel walls arranged on both sides of the channel bottom. Webs are arranged between adjacent channel walls of adjacent flow channels. At least some of the channel bottoms of the multitude of flow channels, the surface of the first metal layer opposite the channel bottom is at least partially substantially planar in a cross-section transverse to the direction of extension of the respective flow channel.

1 . A separator plate for an electrolyser, having a first metal layer,
 the separator plate comprising:   an active region having at least one multitude of flow channels for a reaction medium, said flow channels being embossed into the first metal layer and having a channel bottom and channel walls arranged on both sides of the channel bottom, wherein webs are arranged between adjacent channel walls of adjacent flow channels,   wherein for one, some or all of the channel bottoms of the multitude of flow channels, the surface of the first metal layer opposite the channel bottom is at least partially substantially planar in a cross-section transverse to the direction of extension of the respective flow channel.   
     
     
         2 . The separator plate according to  claim 1 , wherein, for one, some or all of the channel bottoms of the multitude of flow channels, the substantially planar region of the surface opposite the channel bottom has a width BE, determined transversely to the direction of extension of the respective flow channel, for which the following applies in relation to the original sheet thickness BA of the active region of the first metal layer before the active region is embossed into the first metal layer: 1.5 BA≤BE≤4 BA, preferably 2 BA≤BE and/or BE≤3 BA. 
     
     
         3 . The separator plate according to  claim 1 , wherein a substantially planar region has a width BE, determined transversely to the direction of extension of the respective channel, over which the surface of the first metal layer opposite the channel bottom is at a substantially constant distance from a line connecting two points of the channel bottom that have the maximum depth of the channel, said line extending transversely to the direction of extension of the respective channel. 
     
     
         4 . The separator plate according to  claim 3 , a substantially constant distance is given if, over the width BE, the surface opposite the channel bottom is at a distance AO from the straight line connecting the two points of maximum depth, wherein, over the width BE, the distance AO varies around the mean value of AO over the width BE by at most 0.5 AG, wherein AG is the maximum distance of the channel bottom from the straight line connecting the two points of maximum depth. 
     
     
         5 . The separator plate according to  claim 1 , wherein the central axes of adjacent channels have a spacing AK of 7 BA≤AK≤13 BA. 
     
     
         6 . The separator plate according to  claim 1 , wherein, for one, some or all of the channel bottoms of the multitude of flow channels, the channel bottom is at least partially convex, in particular over the width BE, in a cross-section transverse to the direction of extension of the respective flow channel. 
     
     
         7 . The separator plate according to  claim 1 , wherein it is produced in a single-stage or multi-stage forming process. 
     
     
         8 . The separator plate according to  claim 1 , wherein the first metal layer has a layer thickness BA, where 0.2≤BA≤0.8 mm. 
     
     
         9 . The separator plate according to  claim 1 , wherein the first metal layer is made of or comprises stainless steel and/or titanium. 
     
     
         10 . The separator plate according to  claim 1 , wherein the following applies at least in part for the mean spacing AK between adjacent flow channels of a multitude of flow channels embossed into the first metal layer for a reaction medium: 2 mm≤AK. 
     
     
         11 . A die pair for producing a separator plate according to  claim 1  by single-stage forming of the first metal layer using a male die and a female die as dies,
 wherein for each of the surfaces of a flow channel of an active region that are substantially planar after forming, the structure that forms this surface of the active region of the separator plate a) on the die adjacent to this surface is at least partially cambered, in particular convex, in a cross-section perpendicular to the direction of extension of the respective flow channel of the active region, and b) on the other die has a free space, in particular a concave depression, in a cross-section perpendicular to the direction of extension of the respective flow channel. 
 
     
     
         12 . The die pair according to  claim 11 , wherein one, some or all of the cambered structures have an elevation U beyond the regions of the die adjacent to the respective cambered structure in a cross-section perpendicular to the direction of extension of the respective flow channel of the active region, where 10 μm≤U≤150 μm. 
     
     
         13 . The die pair according to  claim 11 , wherein one, some or all of the cambered structures have an elevation U beyond the regions of the die adjacent to the respective cambered structure in a cross-section perpendicular to the direction of extension of the respective flow channel of the active region, where U≥0.05 BA. 
     
     
         14 . A method for producing a separator plate according to  claim 1 ,
 wherein,   in order to form the first metal layer, a metal sheet is arranged between a female die and a male die of a die pair and is formed by means of the die pair.