Interconnect for solid oxide fuel cell and method for manufacturing the same

Abstract

Disclosed herein are an interconnect for a solid oxide fuel cell and a method for manufacturing the same, the interconnect including: a conductive core; an oxidation-resistant insulating part receiving therein; and an oxidation-resistant conductive material layer coated on an exposed surface of the conductive core, which is exposed to an external environment by removing a portion of the oxidation-resistant insulating part, so that the interconnect can maintain durability against high-temperature heat generated from a flat type solid oxide fuel cell for a long time and thus have a very small voltage loss due to oxidation even with the use over a long-time period; have no sealing problem and no delaminating problem of a coating film due to a difference in coefficient of thermal expansion; be inexpensive; and have a simple structure.

What is claimed is: 
     
         1 . An interconnect for a solid oxide fuel cell, the interconnect comprising:
 a conductive core formed of an electroconductive material and taking the form of a lattice type plate;   an oxidation-resistant insulating part receiving and wrapping the conductive core therein, to thereby prevent oxidation of the conductive core; and   an oxidation-resistant conductive material layer coated on an exposed surface of the conductive core, which is exposed to an external environment by removing a portion of the oxidation-resistant insulating part, the oxidation-resistant conductive material layer being electrically connected with an electrode of an external fuel cell.   
     
     
         2 . The interconnect as set forth in  claim 1 , wherein the conductive core includes:
 a plurality of horizontal parts each having a predetermined cross section and extended in a length direction, and in parallel spaced apart from each other; and   a plurality of vertical parts disposed orthogonal with the horizontal parts and in parallel spaced apart from each other, the vertical parts each having a predetermined cross section.   
     
     
         3 . The interconnect as set forth in  claim 2 , wherein the horizontal part and the vertical part each take the form of an I-beam, having flat upper and lower surfaces, upper and lower surfaces of the horizontal part being stepped with respect to upper and lower surfaces of the vertical part. 
     
     
         4 . The interconnect as set forth in  claim 1 , wherein the conductive core is formed of any one of a metal, a metal alloy, and a metal and ceramic alloy, having a melting point of 1000° C. or higher. 
     
     
         5 . The interconnect as set forth in  claim 1 , wherein the oxidation-resistant insulating part is formed of any one or a mixture of one or more of yttria stabilized zirconia (YSZ), scandia stabilized zirconia (ScSZ), gadolinia doped ceria (GDC), and LSGM (La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3−δ ). 
     
     
         6 . The interconnect as set forth in  claim 1 , wherein the oxidation-resistant conductive material layer is formed of a noble metal. 
     
     
         7 . The interconnect as set forth in  claim 1 , wherein the oxidation-resistant insulating part includes some or all of components constituting an electrolyte used in the solid oxide fuel cell. 
     
     
         8 . The interconnect as set forth in  claim 1 , wherein the oxidation-resistant insulating part includes some or all of components constituting a sealing member used in the solid oxide fuel cell. 
     
     
         9 . The interconnect as set forth in  claim 1 , wherein the oxidation-resistant insulating part includes some or all of components constituting a sealing member used in the solid oxide fuel cell and some or all of components constituting an electrolyte used in the solid oxide fuel cell. 
     
     
         10 . The interconnect as set forth in  claim 1 , further comprising a middle layer laminated between the conductive core and the oxidation-resistant insulating part, to prevent delamination of the oxidation-resistant insulating part from the conductive core. 
     
     
         11 . The interconnect as set forth in  claim 10 , wherein the middle layer is formed of a mixture of components of the conductive core and the oxidation-resistant insulating part. 
     
     
         12 . A method for manufacturing an interconnect for a solid oxide fuel cell, the method comprising:
 forming a conductive core in a form of a lattice type plate by sintering-molding a conductive powder having a melting point of 1000° C. or higher;   molding an oxidation-resistant insulating part by wrapping the conductive core in an oxidation-resistant insulating ceramic powder, followed by sintering;   exposing the conductive core to an external environment by mechanically processing a portion of the oxidation-resistant insulating part to expose a portion of the conductive core, which is to be connected with an electrode of the fuel cell; and   coating an oxidation-resistant conductive material layer on an exposed portion of the conductive core by coating an oxidation-resistant conductive material on the exposed portion of the conductive core.   
     
     
         13 . The method as set forth in  claim 12 , further comprising, before the molding of the oxidation-resistant insulating part, forming a middle layer by coating a mixture of the conductive powder and the oxidation-resistant insulating ceramic powder on a surface of the conductive core. 
     
     
         14 . The method as set forth in  claim 12 , wherein in the exposing of the conductive core, the portion of the oxidation-resistant insulating part is removed through a polishing process. 
     
     
         15 . The method as set forth in  claim 12 , wherein in the coating of the oxidation-resistant conductive material layer, the oxidation-resistant conductive material layer is coated on the exposed portion of the conductive core in a deposition manner. 
     
     
         16 . The method as set forth in  claim 15 , wherein a material to be deposited used in the lamination manner includes noble metals.