High-temperature fuel cell system

Patent metadata

Field	Value
Publication number	US-2017338505-A1
Application number	US-201715590859-A
Country	US
Kind code	A1
Filing date	May 9, 2017
Priority date	May 19, 2016
Publication date	Nov 23, 2017
Grant date	—

Abstract

A high-temperature fuel cell system includes a fuel cell that includes an anode and a cathode and that generates power by using a fuel gas and an oxidant gas, a fuel-gas path along which the fuel gas flows, an oxidant-gas path along which the oxidant gas flows, an anode-off-gas path along which an anode off-gas flows, a cathode-off-gas path along which a cathode off-gas flows, a combustion space in communication with the anode-off-gas path and the cathode-off-gas path and in which the anode off-gas and the cathode off-gas are burned, a flue-gas path along which a flue gas flows, a cathode-off-gas branch portion disposed on the cathode-off-gas path between the combustion space and the cathode and at which some of the cathode off-gas is branched from the cathode-off-gas path, and a first heat exchanger that enables heat exchange between the oxidant gas, the flue gas, and the cathode off-gas.

First claim

What is claimed is:

1 . A high-temperature fuel cell system comprising:
a fuel cell that includes an anode and a cathode and that generates power by using a fuel gas and an oxidant gas; a fuel-gas path along which the fuel gas flows; an oxidant-gas path along which the oxidant gas flows; an anode-off-gas path along which an anode off-gas discharged from the anode flows; a cathode-off-gas path along which a cathode off-gas discharged from the cathode flows; a combustion space that is in communication with the anode-off-gas path and the cathode-off-gas path and in which the anode off-gas and the cathode off-gas are burned; a flue-gas path along which a flue gas discharged from the combustion space flows; a cathode-off-gas branch portion that is disposed on the cathode-off-gas path between the combustion space and the cathode and at which some of the cathode off-gas is branched from the cathode-off-gas path; and a first heat exchanger that enables heat exchange between the oxidant gas, the flue gas, and the cathode off-gas that has passed through the cathode off-gas branch portion.

2 . The high-temperature fuel cell system according to claim 1 , further comprising:
a mixing portion that is disposed on the flue-gas path and at which the flue gas and the cathode off-gas that has passed through the cathode-off-gas branch portion are mixed.

3 . The high-temperature fuel cell system according to claim 1 , further comprising:
a reformer that generates, from a source gas, a reformed gas containing hydrogen used as the fuel gas to be supplied to the fuel cell; and a second heat exchanger that enables heat exchange between the reformer and the flue gas, wherein the cathode off-gas that has passed through the cathode-off-gas branch portion, together with the flue gas, is used as a heating fluid of the second heat exchanger.

4 . The high-temperature fuel cell system according to claim 1 , further comprising:
an anode-off-gas ejecting portion that forms part of the anode-off-gas path and from which the anode off-gas is ejected into the combustion space; and a cathode-off-gas gathering portion that forms part of the cathode-off-gas path and at which the cathode off-gas gathers, wherein the cathode-off-gas gathering portion includes a passage member including a cylindrical peripheral wall surrounding the anode-off-gas ejecting portion and a diffuser panel having a cathode-off-gas ejection hole through which the cathode off-gas is ejected into the combustion space inside the peripheral wall, and wherein the cathode-off-gas branch portion is formed on the peripheral wall.

5 . The high-temperature fuel cell system according to claim 1 ,
wherein the cathode-off-gas branch portion is a branch from the cathode-off-gas path.

6 . The high-temperature fuel cell system according to claim 1 ,
wherein the cathode-off-gas branch portion is an opening formed on the cathode-off-gas path.

7 . The high-temperature fuel cell system according to claim 1 , further comprising:
a combustion tube and a combustion chamber that define the combustion space, wherein the cathode off-gas that has passed through the cathode-off-gas branch portion and the flue gas passing along the flue-gas path are mixed outside the combustion space.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Sakai Osamu
• Ukai Kunihiro
• Kaneko Yasushi
• Onuma Shigenori
• Kakuwa Takashi

Classifications

• H01M8/04074

  Heat exchange unit structures specially adapted for fuel cell · CPC title

• H01M8/0618 Primary

  Reforming processes, e.g. autothermal, partial oxidation or steam reforming · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M2300/0074

  Ion conductive at high temperature · CPC title

• H01M8/1233

  with one of the reactants being liquid, solid or liquid-charged · CPC title