Fuel cell system

Patent metadata

Field	Value
Publication number	US-12224464-B2
Application number	US-202218046537-A
Country	US
Kind code	B2
Filing date	Oct 14, 2022
Priority date	Dec 7, 2021
Publication date	Feb 11, 2025
Grant date	Feb 11, 2025

Abstract

An FC system disclosed herein may comprise a plurality of FC units, a cooler, and a controller. Each of the FC units may comprise a FC stack, a supply passage/a return passage/a circulating passage through which refrigerant passes, and first temperature sensor. The supply passage supplies the refrigerant from the cooler to the FC stack. The return passage returns the refrigerant to the cooler. The circulating passage is connected to the supply passage and the return passage. The first temperature sensor is configured to measure a temperature of the refrigerant in the supply passage at a position upstream of a merging point of the supply passage and the circulating passage. When measured values of the first temperature sensors of the plurality of the FC units do not match, the controller is configured to provide notification about malfunction of the first temperature sensor.

First claim

What is claimed is:

1. A fuel cell system comprising:
a plurality of fuel cell units;
a cooler; and
a controller,
wherein
each of the plurality of the fuel cell units comprises:
a fuel cell stack;
a supply passage for supplying refrigerant from the cooler to the fuel cell stack;
a return passage for returning the refrigerant which passed through the fuel cell stack to the cooler;
a circulating passage connected to the supply passage and the return passage, the circulating passage being for returning the refrigerant in the return passage to the supply passage;
a switch valve configured to set a destination of the refrigerant flowing in the return passage to one of the cooler and the circulating passage;
a first temperature sensor configured to measure a temperature of the refrigerant in the supply passage at a position upstream of a merging point of the supply passage and the circulating passage;
a second temperature sensor configured to measure a temperature of the refrigerant in the supply passage at a position downstream of the merging point; and
a third temperature sensor configured to measure a temperature of the refrigerant in the return passage, and

when measured values of the first temperature sensors of the plurality of the fuel cell units do not match, the controller is configured to provide notification about malfunction of the first temperature sensor of at least one of the plurality of fuel cell units.

2. The fuel cell system of claim 1 , wherein when the measured values of the first temperature sensors of the plurality of the fuel cell units match, the controller is configured to, for each of the fuel cell units:
control the switch valve so as not to flow the refrigerant to the circulating passage; and
when a measured value of the first temperature sensor is different from a measured value of the second temperature sensor, provide notification about malfunction of the second temperature sensor.

3. The fuel cell system of claim 2 , wherein, for each of the fuel cell unit, when the measured value of the first temperature sensor and the measured value of the second temperature sensor match, the controller is configured to:
calculate an estimated temperature of the refrigerant at an outlet of the fuel cell stack from the measured value of the second temperature sensor and an output of the fuel cell stack; and
when a measured value of the third temperature sensor is different from the estimated temperature, provide notification about malfunction of the third temperature sensor.

4. The fuel cell system of claim 1 , wherein the controller is configured to, for each of the plurality of the fuel cell unit, operate a pump configured to pump the refrigerant to the fuel cell stack at maximum power while checking the measured value of the second temperature sensor or the third temperature sensor.

5. The fuel cell system of claim 1 , wherein when the measured values of the first temperature sensors of the plurality of the fuel cell units match, the controller is configured to:
stop a specific fuel cell unit among the plurality of the fuel cell units;
operate the fuel cell units other than the specific fuel cell unit so that a total output of the fuel cell system matches a target output;
compare measured values of the first, second and third temperature sensors of the specific fuel cell unit; and
when one of the measured values differs from the other two of the measured values, provide notification about malfunction of the temperature sensor with the different measured value.

Assignees

• Toyota Motor Co Ltd

Inventors

• Egawa Toshihiro
• Okumura Makito
• Iio Atsuo
• Fujioka Hisaya

Classifications

• H01M8/04768

  of the coolant · CPC title

• H01M8/249

  comprising two or more groupings of fuel cells, e.g. modular assemblies · CPC title

• H01M8/04955

  Shut-off or shut-down of fuel cells · CPC title

• G01K13/026 Primary

  of moving liquids · CPC title

• H01M8/04664

  Failure or abnormal function · CPC title