Fuel cell system and method for operating the same

Patent metadata

Field	Value
Publication number	US-2019363377-A1
Application number	US-201916384467-A
Country	US
Kind code	A1
Filing date	Apr 15, 2019
Priority date	May 25, 2018
Publication date	Nov 28, 2019
Grant date	—

Abstract

A fuel cell system includes a fuel feeder that supplies fuel, a fuel cell stack that generates power through an electrochemical reaction using air and a hydrogen-containing gas generated from the fuel, a first temperature sensor that senses the temperature of the fuel cell stack, and a controller. The fuel cell stack has a membrane electrode assembly including an electrolyte membrane through which protons can pass, a cathode on one side of the electrolyte membrane, and an anode on the other side of the electrolyte membrane. The controller defines an upper limit of current output from the fuel cell stack on the basis of the temperature of the fuel cell stack, the supply of the fuel, and the hydrogen consumption of the fuel cell stack associated with internal leakage current and keeps the current output from the fuel cell stack at or below the upper limit.

First claim

What is claimed is:

1 . A fuel cell system comprising:
a fuel feeder that supplies fuel; a fuel cell stack that generates power through an electrochemical reaction using air and a hydrogen-containing gas generated from the fuel; a first temperature sensor that senses a temperature of the fuel cell stack; and a controller, wherein: the fuel cell stack has a membrane electrode assembly including an electrolyte membrane through which protons can pass, a cathode on a first side of the electrolyte membrane, and an anode on a second side of the electrolyte membrane; and the controller defines an upper limit of current output from the fuel cell stack on the basis of the temperature of the fuel cell stack, a supply of the fuel, and hydrogen consumption of the fuel cell stack associated with internal leakage current and keeps the current output from the fuel cell stack at or below the upper limit.

2 . The fuel cell system according to claim 1 , further comprising:
an off-gas path, a passage through which off-gas discharged from the anode passes; and a second temperature sensor that senses a temperature of the off-gas, wherein the controller defines the upper limit of current output from the fuel cell stack on the basis of either the temperature of the fuel cell stack or the temperature of the off-gas, whichever is lower, the supply of the fuel, and the hydrogen consumption of the fuel cell stack associated with internal leakage current and keeps the current output from the fuel cell stack at or below the upper limit.

3 . The fuel cell system according to claim 1 , further comprising
a pressure sensor that senses a pressure of anode gas, a gas that contains at least one of the fuel and the hydrogen-containing gas and is fed to the anode, wherein the controller defines the upper limit of current output from the fuel cell stack on the basis of the temperature of the fuel cell stack, the supply of the fuel, the pressure of the anode gas, and the hydrogen consumption of the fuel cell stack associated with internal leakage current and keeps the current output from the fuel cell stack at or below the upper limit.

4 . The fuel cell system according to claim 3 , further comprising:
an off-gas path, a passage through which off-gas discharged from the anode passes; and a second temperature sensor that senses a temperature of the off-gas, wherein the controller defines the upper limit of current output from the fuel cell stack on the basis of either the temperature of the fuel cell stack or the temperature of the off-gas, whichever is lower, the supply of the fuel, the pressure of the anode gas, and the hydrogen consumption of the fuel cell stack associated with internal leakage current and keeps the current output from the fuel cell stack at or below the upper limit.

5 . The fuel cell system according to claim 1 , further comprising a reformer that reforms the fuel and generates the hydrogen-containing gas.

6 . The fuel cell system according to claim 1 , wherein:
the fuel cell system is one that gives an external load a supply of power from the fuel cell stack; and the controller increases the supply of the fuel if the controller determines that the supply of power from the fuel cell stack, which is based on predetermined performance characteristics of the fuel cell stack, will fail to meet a power requirement of the external load.

7 . The fuel cell system according to claim 1 , further comprising:
a water feeder that supplies water to the fuel cell stack; and an evaporator that evaporates the water supplied from the water feeder.

8 . The fuel cell system according to claim 7 , wherein:
the fuel cell system is one that gives an external load a supply of power from the fuel cell stack; and the controller increases at least one of the supply of the fuel and a supply of the water if the controller determines that the supply of power from the fuel cell stack, which is based on predetermined performance characteristics of the fuel cell stack, will fail to meet a power requirement of the external load.

9 . The fuel cell system according to claim 1 , further comprising a steam feeder that supplies steam to the fuel cell stack.

10 . The fuel cell system according to claim 9 , wherein:
the fuel cell system is one that gives an external load a supply of power from the fuel cell stack; and the controller increases at least one of the supply of the fuel and a supply of the steam if the controller determines that the supply of power from the fuel cell stack, which is based on predetermined performance characteristics of the fuel cell stack, will fail to meet a power requirement of the external load.

11 . A method for operating a fuel cell system that includes:
a fuel feeder that supplies fuel; a fuel cell stack that generates power through an electrochemical reaction using air and a hydrogen-containing gas generated from the fuel; and a first temperature sensor that senses a temperature of the fuel cell stack, the fuel cell stack having a membrane electrode assembly including an electrolyte membrane through which protons can pass, a cathode on a first side of the electrolyte membrane, and an anode on a second side of the electrolyte membrane, the method comprising defining an upper limit of current output from the fuel cell stack on the basis of the temperature of the fuel cell stack, a supply of the fuel, and hydrogen consumption of the fuel cell stack associated with internal leakage current and keeping the current output from the fuel cell stack at or below the upper limit.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Kani Yukimune
• Mikami Yuichi
• Terayama Takeshi

Classifications

• H01M8/04201

  Reactant storage and supply, e.g. means for feeding, pipes · CPC title

• H01M8/04343

  of anode exhausts · CPC title

• H01M8/0491 Primary

  of fuel cell stacks · CPC title

• H01M8/04753

  of fuel cell reactants · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title