Assembling method of solid oxide fuel cell
An assembling method of a solid oxide fuel cell, having a stack structure in which sheet bodies and separators are stacked in alternating layers, includes a stacking step, a sealing step, and a reduction process step. In the sealing step, a laminate in which a crystallized glass material is interposed between the perimetric portions adjacent to each other is heated, so that the crystallization rate of the crystallized glass is increased to 0 to 50%. Accordingly, the perimetric portions adjacent to each other are integrated and sealed, and a room for glass softening is left. In the reduction process step, the laminate is heated, and a reduction gas is supplied into a fuel channel, whereby the reduction process is performed to the fuel electrode layer, and the crystallization rate is increased to 70 to 100%. Thus, the assembly of the fuel cell is completed.
1. An assembling method of a solid oxide fuel cell, the solid oxide fuel cell including:
a single or a plurality of sheet bodies that has a solid electrolyte layer, a fuel electrode layer formed on an upper surface of the solid electrolyte layer, and an air electrode layer formed on an lower surface of the solid electrolyte layer, these layers being stacked and fired; and
a plurality of support members for supporting the single or the plurality of sheet bodies, wherein the single or the plurality of sheet bodies and the support members are stacked in alternating layers, wherein
for each sheet body, an upper surface of a perimetric portion of the sheet body and a lower surface of a perimetric portion of an upper support member that is a support member adjacent to the upper surface of the sheet body, as well as a lower surface of the perimetric portion of the sheet body and an upper surface of the perimetric portion of a lower support member that is a support member adjacent to the lower surface of the sheet body, are respectively sealed in order that the perimetric portion of the sheet body is held between the lower surface of the perimetric portion of the upper support member and the upper surface of the perimetric portion of the lower support member, and
for each sheet body, a fuel channel through which a fuel gas is supplied is defined and formed in a space formed between a lower surface of a plane portion located at an inner side from the perimetric portion of the upper support member and an upper surface of the fuel electrode layer in the sheet body, and an air channel through which a gas containing oxygen is supplied is defined and formed in a space formed between an upper surface of the plane portion located at the inner side from the perimetric portion of the lower support member and a lower surface of the air electrode layer in the sheet body, the method sequentially comprising:
a stacking step in which the single or plurality of sheet bodies and the support members are stacked in alternating layers with a crystallized glass material interposed between the perimetric portion of each of the single or plurality of sheet bodies and the perimetric portion of each of the support members adjacent to the sheet body;
a sealing step in which a crystallization rate of the crystallized glass is increased from 0 to 50% through heat application to the resultant laminate in order to seal the perimetric portion of each of the single or the plurality of sheet bodies and the perimetric portion of each of the support members adjacent to each of the single or plurality of sheet bodies; and
a reduction process step in which the resultant laminate, which has been subjected to the sealing step, is heated and a reduction gas is supplied into the fuel channel, by which the crystallization rate of the crystallized glass is increased to 70 to 100%, and a reduction process is performed to the fuel electrode layer.
2. The assembling method of a solid oxide fuel cell according to claim 1 , wherein a thickness of each of the single or the plurality of sheet bodies is 20μ or more and 500μ or less.
3. The assembling method of a solid oxide fuel cell according to claim 1 , wherein the heat application in the sealing step is at a temperature within the range of 500 to 800° C., and a heating treatment temperature in the reduction process step is within the range of 650 to 950° C.
4. The assembling method of a solid oxide fuel cell according to claim 1 , wherein the sealing step is performed at a first temperature for a predetermined time, and the reduction process step is performed at a second temperature, higher than said first temperature, for a predetermined time.