JP-7855538-B2 - Apparatus for calculating the degree of cell degradation of an electrochemical cell stack, a cell degradation calculation system, a cell degradation calculation method, and a cell degradation calculation program.

JP7855538B2JP 7855538 B2JP7855538 B2JP 7855538B2JP-7855538-B2

Inventors

椎野佳祐
霜鳥宗一郎
水口浩司

Assignees

株式会社東芝
東芝エネルギーシステムズ株式会社

Dates

Publication Date: 20260508
Application Date: 20230302

Claims (7)

An electrochemical cell stack cell degradation degree calculation device for calculating the degree of degradation of cells in an electrochemical cell stack, A first acquisition unit acquires first characteristic data showing the voltage-current characteristics of the cell, A second acquisition unit acquires second characteristic data showing the voltage-current characteristics of the cell when it is new, A first calculation unit calculates a first target voltage value that indicates a voltage value corresponding to a reference current value based on the first characteristic data, A second calculation unit calculates a second target voltage value that indicates a voltage value corresponding to the reference current value based on the second characteristic data, A third calculation unit calculates a cell degradation degree indicating the degree of degradation of the cell based on the first target voltage value and the second target voltage value, Equipped with, The third calculation unit calculates the cell degradation degree by dividing the difference obtained by subtracting the first target voltage value from the second target voltage value by the second target voltage value. A device for calculating the degree of cell degradation in an electrochemical cell stack.
The system further includes a reference setting unit for setting the aforementioned reference current value, The reference setting unit sets the reference current value to a current value that is greater than the current value when the voltage value is zero, based on the first characteristic data. A device for calculating the degree of cell degradation of an electrochemical cell stack according to claim 1 .
The cell degradation degree calculation device for an electrochemical cell stack according to claim 2 , wherein the reference setting unit sets the reference current value to the minimum current value at which the rate of change of the voltage value with respect to the current value is less than or equal to a rate of change threshold.
The system further includes a determination unit that determines whether the cell degradation level calculated by the third calculation unit is equal to or greater than a degradation threshold. A device for calculating the degree of cell degradation of an electrochemical cell stack according to any one of claims 1 to 3 .
An electrochemical cell stack cell degradation calculation system for calculating the degree of degradation of cells in an electrochemical cell stack, A device for calculating the degree of cell degradation of an electrochemical cell stack according to any one of claims 1 to 3 , A first database for storing the first characteristic data, The system comprises a second database for storing the second characteristic data, The first acquisition unit acquires the first characteristic data from the first database, The second acquisition unit acquires the second characteristic data from the second database. A system for calculating the degree of cell degradation in electrochemical cell stacks.
A method for calculating the degree of cell degradation in an electrochemical cell stack, wherein the degree of cell degradation in an electrochemical cell stack is calculated, The steps include: acquiring first characteristic data showing the voltage-current characteristics of the cell; A step of acquiring second characteristic data showing the voltage-current characteristics of the cell when it is new, The steps include: calculating a first target voltage value that indicates a voltage value corresponding to a reference current value based on the first characteristic data; A step of calculating a second target voltage value that indicates a voltage value corresponding to the reference current value based on the second characteristic data, The process includes the step of calculating a cell degradation degree indicating the degree of degradation of the cell based on the first target voltage value and the second target voltage value, The degree of degradation of the cell is calculated by dividing the difference obtained by subtracting the first target voltage value from the second target voltage value by the second target voltage value. Method for calculating the degree of cell degradation in an electrochemical cell stack.
An electrochemical cell stack cell degradation calculation program that causes a computer to execute a method for calculating the degree of degradation of cells in an electrochemical cell stack, The cell degradation degree calculation method is as follows: The steps include: acquiring first characteristic data showing the voltage-current characteristics of the cell; A step of acquiring second characteristic data showing the voltage-current characteristics of the cell when it is new, The steps include: calculating a first target voltage value that indicates a voltage value corresponding to a reference current value based on the first characteristic data; A step of calculating a second target voltage value that indicates a voltage value corresponding to the reference current value based on the second characteristic data, The process includes the step of calculating a cell degradation degree indicating the degree of degradation of the cell based on the first target voltage value and the second target voltage value, The degree of degradation of the cell is calculated by dividing the difference obtained by subtracting the first target voltage value from the second target voltage value by the second target voltage value. A program for calculating the degree of cell degradation in an electrochemical cell stack.

Description

The embodiments relate to a cell degradation degree calculation apparatus, a cell degradation degree calculation system, a cell degradation degree calculation method, and a cell degradation degree calculation program for an electrochemical cell stack. Electrochemical cell stacks, which constitute fuel cells, water electrolyzers, and carbon dioxide electrolyzers, are constructed by stacking multiple cells. The membrane electrode assembly constituting each cell includes an anode electrode, a cathode electrode, and an electrolyte membrane interposed between the anode and cathode electrodes. With continued use of the electrochemical cell stack, the catalyst materials contained in the anode and cathode electrodes, as well as the electrolyte membrane, may deteriorate. In this case, the performance of the electrochemical cell stack may decrease. Japanese Patent Publication No. 2015-069948Japanese Patent Publication No. 2019-160701Japanese Patent Publication No. 2022-137607Japanese Patent Publication No. 2021-046575Japanese Patent Publication No. 2012-214904 Figure 1 is a cross-sectional view showing a schematic configuration of the electrochemical cell stack according to this embodiment.Figure 2 is a plan view showing the cell shown in Figure 1.Figure 3 shows the schematic system configuration of the electrochemical cell stack shown in Figure 1.Figure 4 shows the cell degradation degree calculation system for an electrochemical cell stack according to this embodiment.Figure 5 is a schematic diagram illustrating the first characteristic data stored in the first database shown in Figure 4.Figure 6 is a schematic diagram illustrating the second characteristic data stored in the second database shown in Figure 4.Figure 7 is a graph showing the voltage-current characteristics of the cell.Figure 8 is a diagram illustrating the measurement method for obtaining the characteristic data shown in Figures 5 and 6.Figure 9 is a flowchart showing the method for calculating the degree of cell degradation of an electrochemical cell stack according to this embodiment. Next, the cell degradation degree calculation device, cell degradation degree calculation system, cell degradation degree calculation method, and cell degradation degree calculation program for the electrochemical cell stack according to this embodiment will be described. First, the electrochemical cell stack according to this embodiment will be described. The electrochemical cell stack is used in electrolysis devices for carbon dioxide or water, or in fuel cells, etc. As shown in Figure 1, the electrochemical cell stack 1 comprises a pair of current collector plates 2, a plurality of cells 10 stacked between the pair of current collector plates 2, and a plurality of separators 30 stacked alternately with the cells 10. Each cell 10 includes a membrane electrode assembly (MEA) 10M and a cell frame 20. The cells 10, separators 30, and current collector plates 2 are clamped and pressed together by a pair of clamping plates 3. The pair of clamping plates 3 are fastened together using bolts and nuts (not shown). An insulating plate 4 is interposed between the clamping plates 3 and the current collector plates 2. The membrane electrode assembly 10M includes a cathode electrode 11, an anode electrode 12, and an electrolyte membrane 13 interposed between the cathode electrode 11 and the anode electrode 12. The membrane electrode assembly 10M is formed in a thin plate shape. The membrane electrode assembly 10M may also be formed in a rectangular shape when viewed in the stacking direction D of the electrochemical cell stack 1. The cathode electrode 11 includes a cathode catalyst layer 11a and a cathode gas diffusion layer 11b. The cathode catalyst layer 11a is in contact with the electrolyte membrane 13. The cathode gas diffusion layer 11b is in contact with the separator 30 and diffuses the cathode fluid supplied from the cathode channel (described later). When the electrochemical cell stack 1 is used in an electrolysis apparatus, the cathode gas diffusion layer 11b may be formed from, for example, carbon paper or titanium nonwoven fabric. The cathode gas diffusion layer 11b is bonded to the cathode catalyst layer 11a. If the cathode catalyst layer 11a can diffuse the cathode fluid, the cathode gas diffusion layer 11b may not be necessary. The anode electrode 12 includes an anode catalyst layer 12a and an anode gas diffusion layer 12b. The anode catalyst layer 12a is in contact with the electrolyte membrane 13. The anode gas diffusion layer 12b is in contact with the separator 30 and diffuses the anode fluid supplied from the anode channel 32 (described later). When the electrochemical cell stack 1 is used in an electrolysis apparatus, the anode gas diffusion layer 12b may be formed of, for example, carbon paper or titanium nonwoven fabric. The anode gas diffusion layer 12b is bonded to the anode catalyst layer 12a. If the anode catalyst layer 12a can diffuse the anode fluid