Electrode resistance measuring device

Abstract

The present invention is to provide an electrode resistance measuring device that measures the through-plane resistance of an electrode and realizes monolithic measurement of individual electrodes with high reproducibility, the device comprising: a lower terminal, the top surface of which is in close contact with the bottom surface of the electrode to be measured; and a resistance measuring unit electrically connected to the upper terminal and the lower terminal so as to measure a resistance of the electrode to be measured, in which a microporous layer is formed on a bottom surface of the upper terminal and a top surface of the lower terminal.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0178973 filed on December 20, 2022, the disclosure of which is incorporated herein in its entirety as a part of this specification.

[0002] The present disclosure relates to an electrode resistance measuring device, and to an electrode resistance measuring device capable of realizing monolithic measurement of individual electrodes, which has high reproducibility in measuring the through-surface resistance of the electrode. Background Art

[0003] The resistance measurement methods of electrodes or auxiliary materials prepared for secondary batteries, fuel cells, etc. are divided into in-plane resistance measurement methods and through-plane resistance measurement methods.

[0004] When driving an actual battery, the through-plane resistance of the electrode that matches the direction of electron flow is directly related to the performance of the battery.

[0005] Furthermore, through-the-sheet resistance measurements make it possible to identify non-uniformities in the vertical direction of electrodes coated using wet coating methods and can be applied to quality control of batteries.

[0006] like Figure 1 As shown, the conventional through-surface resistance measurement can be performed by applying a current to the two terminals 1101 and 1102 and measuring their resistances after a pair of terminals 1101 and 1102 for measuring the resistance of the electrode 1011 are attached to both sides of the electrode 1011, respectively, through the power supply device 1200. The contact portions of the terminals 1101 and 1102 for measuring the resistance of the electrode can be formed as a flat surface. At this time, due to the high contact resistance between the electrode 1011 and the terminals 1101 and 1102, the reproducibility of the through-surface resistance measurement is poor.

[0007] According to the related art, in order to increase the reproducibility of through-plane resistance measurement, there is a method of stacking several electrodes and then squeezing them at high voltage. This measurement method also has difficulty in obtaining uniform values ​​due to uneven contact caused by accumulated contact resistance and steps between multiple electrodes and between the outermost electrode and the terminal. In addition, the analysis method performed by stacking multiple electrodes has difficulty in analyzing the characteristics of individual electrodes.

[0008] There is a need for a through-the-surface resistance measurement technique with excellent reproducibility that solves the above-mentioned problems and is capable of measuring individual electrodes. Summary of the invention

[0009] Technical goals

[0010] The present disclosure relates to an electrode resistance measuring device, and provides an electrode resistance measuring device capable of realizing monolithic measurement of individual electrodes, which has high reproducibility in measuring the through-plane resistance of the electrode.

[0011] The technical objectives to be achieved by the present disclosure are not limited to the above-mentioned technical objectives, and those skilled in the art will clearly understand other technical tasks not mentioned according to the following description.

[0012] Technical Solution

[0013] The electrode resistance measuring device of the present disclosure may include: an upper terminal, the bottom surface of which is in close contact with the upper surface of the measurement target electrode; a lower terminal, an upper surface of which is in close contact with a lower surface of the measurement target electrode; and a resistance measuring unit electrically connected to the upper terminal and the lower terminal to measure the resistance of the measurement target electrode, Among them, the microporous layer may be formed on the bottom surface of the upper terminal and the upper surface of the lower terminal.

[0014] Beneficial effects

[0015] The electrode resistance measurement apparatus of the present disclosure measures the through-plane resistance of an electrode, which can achieve monolithic measurement of individual electrodes with high reproducibility.

[0016] The electrode resistance measuring apparatus of the present disclosure can minimize the contact resistance between the electrode and the terminal when measuring the through-plane resistance.

[0017] The electrode resistance measuring apparatus of the present disclosure can obtain resistance measurement values ​​of individual electrodes in a state where contact resistance is minimized by forming a microporous conductive layer on the surface of the terminal in contact with the electrode, completely adhering to the rough surface of the individual electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view illustrating a through-plane resistance measuring method according to the related art.

[0019] Figure 2 is a perspective view showing an embodiment of an electrode resistance measuring apparatus of the present disclosure.

[0020] Figure 3 is a cross-sectional view showing a state in which the upper terminal and the lower terminal are in close contact with the measurement target electrode.

[0021] Figure 4 is a perspective view showing another embodiment of the electrode resistance measuring apparatus of the present disclosure.

[0022] Figure 5 is a graph showing through-plane resistance measurement values ​​according to Examples 1 and 2 and a comparative example. DETAILED DESCRIPTION

[0023] The electrode resistance measuring device of the present disclosure may include: an upper terminal, the bottom surface of which is in close contact with the upper surface of the measurement target electrode; a lower terminal, an upper surface of which is in close contact with a lower surface of the measurement target electrode; and a resistance measuring unit electrically connected to the upper terminal and the lower terminal to measure the resistance of the measurement target electrode, Among them, the microporous layer may be formed on the bottom surface of the upper terminal and the upper surface of the lower terminal.

[0024] In the electrode resistance measuring apparatus of the present disclosure, the material of the microporous layer may include at least one of carbon, a conductive metal, and a conductive polymer.

[0025] In the electrode resistance measuring device of the present disclosure, the microporous layer of the upper terminal can be formed by placing D 50 The microporous layer of the lower terminal can also be formed by coating or bonding fine particles with a width of 5 μm or less or a fine fiber mesh with a width of 10 μm or less to the bottom surface of the conductive pressure plate made of a rigid material. 50 The fine particles with a size of 5 μm or less or the fine fiber web with a width of 10 μm or less are coated or bonded to the upper surface of a conductive support plate made of a rigid material, and the material of the fine particles or the fine fiber web coated or bonded to the upper and lower terminals may include at least one of transition metals, aluminum, carbon and conductive polymers.

[0026] In the electrode resistance measuring device of the present disclosure, the upper terminal may include a conductive pressure plate made of a conductive material and having a bottom surface formed as a plane perpendicular to the vertical direction, and a first gas diffusion layer (GDL) fixed to the bottom surface of the conductive pressure plate, and the lower terminal may include a conductive support plate made of a conductive material and having an upper surface formed as a plane perpendicular to the vertical direction, and a second GDL fixed to the upper surface of the conductive support plate, wherein the conductive paste may fix the first GDL and the conductive pressure plate between the first GDL and the conductive pressure plate and fix the second GDL and the conductive support plate between the second GDL and the conductive support plate.

[0027] In the electrode resistance measuring apparatus of the present disclosure, the material of the conductive pressure plate and the conductive support plate may include at least one of transition metals on the periodic table, aluminum, and carbon.

[0028] In the electrode resistance measuring apparatus of the present disclosure, the first GDL and the second GDL may include a microporous layer and a carbon fiber layer.

[0029] In the electrode resistance measuring device of the present disclosure, the upper surface of the carbon fiber layer of the first GDL can be adhered to the bottom surface of the conductive pressure plate by a conductive paste, and in the first GDL, the microporous layer can be stacked on the bottom surface of the carbon fiber layer, and the bottom surface of the carbon fiber layer of the second GDL can be adhered to the upper surface of the conductive support plate by a conductive paste, and in the second GDL, the microporous layer can be stacked on the upper surface of the carbon fiber layer.

[0030] In the electrode resistance measuring device of the present disclosure, the conductive paste may be obtained by mixing conductive particles, a binder, and a solvent in a paste state, the material of the conductive particles of the conductive paste may include at least one of carbon black, graphite, CNT, graphene, transition metal, and aluminum, and the size of the conductive particles of the conductive paste may be 20 μm or less. 50 .

[0031] In the electrode resistance measuring apparatus of the present disclosure, the conductive paste may be formed to a thickness of 20 μm to 200 μm between the first GDL and the conductive pressure plate and between the second GDL and the conductive support plate.

[0032] In the electrode resistance measuring apparatus of the present disclosure, the porosity of the microporous layer of the first GDL and the microporous layer of the second GDL may be 30% to 80%.

[0033] In the electrode resistance measuring apparatus of the present disclosure, the thickness of the microporous layer of the first GDL and the microporous layer of the second GDL may be 20 μm to 150 μm.

[0034] In the electrode resistance measuring apparatus of the present disclosure, a support for pressing the measurement target electrode may be stacked on an upper surface of the upper terminal.

[0035] In the electrode resistance measuring apparatus of the present disclosure, each of the upper terminal and the support body may be provided in a disk shape.

[0036] Mode for Carrying Out the Invention

[0037] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. In the process, the size or shape of the components shown in the accompanying drawings may be exaggerated for clarity and convenience of description. In addition, the terms specifically defined in consideration of the configuration and operation of the present disclosure may vary according to the intention or customization of the user or operator. These terms should be defined based on the content throughout this specification.

[0038] In the description of the present disclosure, it should be noted that terms such as "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "one side", and "the other side" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships placed when the products of the present disclosure are used daily. They are merely for the purpose of explaining and briefly describing the present disclosure, and do not suggest or imply that the displayed devices or elements must be configured or operated in a specified orientation, nor should they be understood as limitations on the present disclosure.

[0039] Figure 2 is a perspective view showing an embodiment of an electrode resistance measuring apparatus of the present disclosure. Figure 3 1 is a cross-sectional view showing a state in which the upper terminal 100 and the lower terminal 200 are in close contact with the measurement target electrode 11 . Figure 4 is a perspective view showing another embodiment of the electrode resistance measuring apparatus of the present disclosure. Figure 5 is a graph showing through-plane resistance measurement values ​​according to Examples 1 and 2 and a comparative example.

[0040] In the following, reference is made to Figures 2 to 5 , the electrode resistance measuring device of the present disclosure will be described in detail. Hereinafter, in the description, the vertical direction may be the gravity direction.

[0041] The electrode resistance measuring apparatus of the present disclosure is capable of measuring the through-plane resistance with high reproducibility for individual electrodes.

[0042] like Figure 2 As shown, the electrode resistance measuring device of the present disclosure may include: An upper terminal 100, a bottom surface of which is in close contact with an upper surface of the measurement target electrode 11; a lower terminal 200 whose upper surface is in close contact with the lower surface of the measurement target electrode 11; and a resistance measuring unit 300 electrically connected to the upper terminal 100 and the lower terminal 200 to measure the resistance of the measurement target electrode 11, The microporous layers 111 and 211 may be formed on the bottom surface of the upper terminal 100 and the upper surface of the lower terminal 200 .

[0043] In the electrode resistance measuring device of the present disclosure, the measuring target electrode 11 can be set to a planar shape perpendicular to the vertical direction. Specifically, the measuring target electrode 11 can be made of a conductive material and can be provided in the shape of a plate or a sheet. For example, the measuring target electrode 11 can be formed by applying an electrode slurry to a Cu foil or an Al foil and then drying it. The electrode slurry can be obtained by mixing an active material, a conductive material, a binder and a solvent in a paste state, or can be obtained by mixing a conductive material, a binder and a solvent in a paste state to improve the adhesion between an electrode containing an active material and a conductive foil as a current collector. At this time, the surface on which the electrode slurry is dried may be rough depending on the situation and may not be formed into an ideal plane.

[0044] like Figure 2 and Figure 4 As shown, the area of ​​the bottom surface of the upper terminal 100 or the upper surface of the lower terminal 200 can be formed to be equal to or smaller than the area of ​​the measurement target electrode 11. In the electrode resistance measuring device of the present disclosure, since the bottom surface of the upper terminal 100 and the upper surface of the lower terminal 200 are formed by the microporous layers 111 and 211, and the thickness of the measurement target electrode 11 can be formed to be very thin, when the area of ​​the bottom surface of the upper terminal 100 and the upper surface of the lower terminal 200 are formed to be larger than the area of ​​the measurement target electrode 11, the upper terminal 100 and the lower terminal 200 may be in direct contact. Therefore, it may be desirable that the area of ​​the bottom surface of the upper terminal 100 or the upper surface of the lower terminal 200 be formed to be equal to or smaller than the area of ​​the measurement target electrode 11.

[0045] In the electrode resistance measuring device of the present disclosure, the microporous layer (111, 211) can be formed by applying a carbon paste to a carbon fiber layer (112, 212) such as carbon paper, followed by drying and heat treatment. The carbon paste formed into the microporous layer (111, 211) after drying and heat treatment can be obtained by mixing carbon powder, fluororesin, water and ethanol.

[0046] The resistance measuring unit 300 of the present disclosure may include a current supplier for supplying an input current between the upper terminal 100 and the lower terminal 200, and a voltmeter for measuring a voltage between the upper terminal 100 and the lower terminal 200. The input current is not limited to alternating current or direct current, and may vary according to the purpose of analysis. The resistance measuring unit 300 may be electrically connected to each of the upper terminal 100 and the lower terminal 200 via a conductive cable 150.

[0047] like Figure 3As shown, in the electrode resistance measuring device of the present disclosure, the upper terminal 100 may include a conductive pressure plate 130 made of a conductive material and having a bottom surface formed as a plane perpendicular to the vertical direction, and a first gas diffusion layer (GDL) 110 fixed to the bottom surface of the conductive pressure plate 130, and the lower terminal 200 may include a conductive support plate 230 made of a conductive material and having an upper surface formed as a plane perpendicular to the vertical direction, and a second GDL 210 fixed to the upper surface of the conductive support plate 230.

[0048] In addition, the conductive pastes 120 and 220 may fix the first GDL 110 and the conductive pressure plate 130 between them, and fix the second GDL 210 and the conductive support plate 230 between them.

[0049] The electrode resistance measuring device of the present disclosure can prevent the relative position between the conductive pressure plate 130 and the first GDL 110 and the conductive support plate 230 and the second GDL 210 made of different materials from changing by fixing them with the conductive pastes 120 and 220, and prevent the contact condition at the interface from changing by filling the gap at the interface between them with the conductive pastes 120 and 220. Specifically, after applying the conductive paste 120 to the bottom surface of the conductive pressure plate 130 or the upper surface of the first GDL, the conductive pressure plate 130 and the first GDL 110 can be brought into close contact with each other and then dried to fix the conductive pressure plate 130 and the first GDL 110 to each other. Similarly, after applying the conductive paste 220 between the conductive support plate 230 and the second GDL 210, the conductive support plate 230 and the second GDL 210 can be brought into close contact with each other and then dried to fix the conductive support plate 230 and the second GDL 210 to each other.

[0050] The material of the conductive pressure plate 130 and the conductive support plate 230 may include at least one of a transition metal, aluminum, and carbon on the periodic table. For example, the transition metal may be SUS, copper, titanium, nickel, and the like. As another example, the conductive pressure plate 130 and the conductive support plate 230 may be made by coating the surface of a rigid material with a conductive material such as gold. In other words, the conductive pressure plate 130 and the conductive support plate 230 may be made of a rigid conductive material. In a state where the bottom surface of the conductive pressure plate 130 and the upper surface of the conductive support plate 230 face each other, when the measurement target electrode 11 is between the conductive pressure plate 130 and the conductive support plate 230, the conductive pressure plate 130 and the conductive support plate 230 may be brought into close contact with the measurement target electrode 11 by pressing the conductive pressure plate downward.

[0051] The first GDL 110 and the second GDL 210 may include microporous layers 111 and 211 and carbon fiber layers 112 and 212. As described above, the first GDL 110 and the second GDL 210 may be prepared by applying a carbon paste to the carbon fiber layers 112 and 212 (e.g., carbon paper), followed by drying and heat treatment to form the microporous layers 111 and 211. The carbon paste forming the microporous layers (111, 211) after drying and heat treatment may be obtained by mixing carbon powder, fluororesin, water, and ethanol. The fluororesin may be one or more selected from the group consisting of polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF).

[0052] The carbon fiber layer (112, 212) may be formed of carbon fiber. The carbon fiber (CF) may be a fibrous carbon material having a carbon element mass content of 90% or more. Specifically, the carbon fiber may be a fiber having a graphite structure mainly obtained by pyrolysis of an organic precursor (material before carbonization) fiber. In addition, the carbon fiber layer (112, 212) may be coated with a fluororesin.

[0053] like Figure 3 As shown, the upper surface of the carbon fiber layer 112 of the first GDL 110 may be adhered to the bottom surface of the conductive pressure plate 130 by the conductive paste 120, the microporous layer 111 may be stacked on the bottom surface of the carbon fiber layer 112 of the first GDL 110, the bottom surface of the carbon fiber layer 212 of the second GDL 210 may be adhered to the upper surface of the conductive support plate 230 by the conductive paste 220, and the microporous layer 211 may be stacked on the upper surface of the carbon fiber layer 212 in the second GDL 210. In other words, the electrode resistance measuring apparatus of the present disclosure can improve the reproducibility when measuring the through-surface resistance by minimizing the contact resistance by adhering the carbon fiber layers 112 and 212 of the GDL to the conductive pressure plate 130 and the conductive support plate 230 (the conductive pressure plate 130 and the conductive support plate 230 are made of a material that is conducive to forming a flat surface with high-quality smoothness) with the conductive pastes 120 and 220, and making the microporous layers 111 and 211 of the GDL closely contact the surface of the measurement target electrode 11 with poor smoothness.

[0054] The conductive paste (120, 220) may be obtained by mixing conductive particles, a binder, and a solvent in a paste state. The material of the conductive particles of the conductive paste (120, 220) may include at least one of carbon black, graphite, CNT, graphene, transition metal, and aluminum. The size of the conductive particles of the conductive paste (120, 220) may be 20 μm or less. 50 .

[0055] The conductive paste (120, 220) may be formed to a thickness of 20 μm to 200 μm between the first GDL 110 and the conductive pressure plate 130 and between the second GDL 210 and the conductive support plate 230. The thickness of the conductive pastes 120 and 220 may be determined in consideration of the state of the carbon fiber layers 112 and 212 or the smoothness of the conductive pressure plate 130 and the conductive support plate 230.

[0056] The porosity of the microporous layer 111 of the first GDL 110 and the microporous layer 211 of the second GDL 210 may be 30% to 80%. More preferably, the porosity of the microporous layer 111 of the first GDL 110 and the microporous layer 211 of the second GDL 210 may be 40% to 70%. The microporous layer 111 of the first GDL 110 and the microporous layer 212 of the second GDL 210 may have a thickness of 20 μm to 150 μm.

[0057] As another example, the microporous layer of the upper terminal can be formed by placing D 50 The microporous layer of the lower terminal can be formed by coating or bonding fine particles with a width of 5 μm or less or a fine fiber network with a width of 10 μm or less to the bottom surface of the conductive pressure plate made of a rigid material. In addition, the microporous layer of the lower terminal can also be formed by 50 The conductive support plate is formed by coating or bonding fine particles with a diameter of 5 μm or less or a fine fiber mesh with a width of 10 μm or less to the upper surface of the conductive support plate made of a rigid material. At this time, the material of the fine particles or fine fiber mesh coated or bonded to the upper terminal and the lower terminal may include at least one of transition metals, aluminum, carbon and conductive polymers.

[0058] like Figure 4 As shown, a support body 140 for squeezing the measurement target electrode 11 can be stacked on the upper surface of the upper terminal 100. A plurality of support bodies 140 can be provided. When measuring the through-surface resistance, the amount of pressure applied to the measurement target electrode 11 by the upper terminal 100 can affect the measurement result. Therefore, it is necessary to pressurize the measurement target electrode 11 at an appropriate pressure level, and in the electrode resistance measuring device of the present disclosure, the pressure of the upper terminal 100 squeezing the measurement target electrode 11 can be adjusted by adjusting the number of support bodies 140. The pressure of the upper terminal 100 squeezing the measurement target electrode 11 can preferably be 0.01kgf / cm 2 Up to 0.2kgf / cm 2 If the pressure of the upper terminal 100 pressing the measurement target electrode 11 is less than 0.01kgf / cm 2 , the contact resistance may increase and the measurement accuracy may decrease, and if the pressure of the upper terminal 100 pressing the measurement target electrode 11 exceeds 0.2 kgf / cm 2 , the thickness of the measurement target electrode 11 may change, thereby affecting the measurement value.

[0059] The upper terminal 100 and the support body 140 can be arranged in a disc shape. In order to perform accurate measurements in the electrode resistance measuring device of the present disclosure, it may be important that the upper terminal 100 is not tilted. Therefore, the upper terminal 100 and the support body 140 can be arranged in a disc shape so as not to have anisotropy with respect to a direction perpendicular to the vertical direction. The upper terminal 100 can be provided with an alignment device for aligning the center of the support body 140 with the center of the upper terminal 100. The alignment device can be a protrusion, a groove, a mark, etc. The conductive cable 150 for the electrical connection between the upper terminal 100 and the resistance measuring unit 300 can be laterally connected to the upper terminal 100 so as not to interfere with the stacking of the support body 140.

[0060] Example 1

[0061] The cathode of the lithium secondary battery is prepared as a 19.6 cm 2 The measurement target electrode 11.

[0062] The conductive pressure plate 130 and the conductive support plate 230 were made of SUS material, and the total weight of the upper terminal 100 and the load body 140 was prepared to be 0.3 kg. The first GDL 110 and the second GDL 210 were prepared using Sigracet 39 BC from SGL.

[0063] The conductive pastes 120 and 220 are applied between the conductive pressure plate 130 and the first GDL 110 and between the conductive support plate 230 and the second GDL 210 and then dried so that the conductive pressure plate 130 and the first GDL 110 and the conductive support plate 230 and the second GDL 210 are fixed to each other.

[0064] As the resistance measuring unit 300 , Hioki BT3563 HiTESTER from Hioki Corporation was used. An alternating current of 1 kHz was applied between the upper terminal 100 and the lower terminal 200 as an input current.

[0065] After the measurement target electrode 11 is completely separated from the upper terminal 100 and the lower terminal 200 , the measurement is repeated three times.

[0066] Example 2

[0067] The cathode of the lithium secondary battery is prepared as a 19.6 cm 2 The measurement target electrode 11.

[0068] The conductive pressure plate 130 and the conductive support plate 230 were made of SUS material, and the total weight of the upper terminal 100 and the load body 140 was prepared to be 0.3 kg. The first GDL 110 and the second GDL 210 were prepared using Sigracet 39 BC from SGL.

[0069] The conductive pressure plate 130 and the first GDL 110 and the conductive support plate 230 and the second GDL 210 are in direct close contact without being fixed with a conductive paste therebetween.

[0070] As the resistance measuring unit 300 , Hioki BT3563 HiTESTER from Hioki Corporation was used. An alternating current of 1 kHz was applied between the upper terminal 100 and the lower terminal 200 as an input current.

[0071] After the measurement target electrode 11 is completely separated from the upper terminal 100 and the lower terminal 200 , the measurement is repeated three times.

[0072] Comparative Example

[0073] The cathode of the lithium secondary battery is prepared as a 19.6 cm 2 The measurement target electrode 11.

[0074] The conductive pressure plate 130 and the conductive support plate 230 are made of SUS material, and the total weight of the upper terminal 100 and the load body 140 is prepared to be 0.3 kg.

[0075] like Figure 1 As shown, the conductive pressure plate 130 and the measurement target electrode 11 as well as the conductive support plate 230 and the measurement target electrode 11 are in direct and tight contact without any GDL interposed therebetween.

[0076] As the resistance measuring unit 300 , Hioki BT3563 HiTESTER from Hioki Corporation was used. An alternating current of 1 kHz was applied between the upper terminal 100 and the lower terminal 200 as an input current.

[0077] After the measurement target electrode 11 is completely separated from the upper terminal 100 and the lower terminal 200 , the measurement is repeated three times.

[0078] Figure 5 The resistance values ​​shown may be the average of repeated measurements. Figure 5 As shown, in the through-surface resistance measurement, when the microporous layer 111 is present on the surface of the terminal in contact with the measurement target electrode 11, it can be seen that the measured resistance value decreases rapidly. In particular, in the case of Example 1 and the comparative example, it can be seen that the measured resistance values ​​differ by about 50 times or more. This is because the contact resistance that interferes with the measurement has been minimized. In addition, as a result of calculating the accuracy of Examples 1 and 2 and the comparative example, it is calculated to be 0.55%, 2.36% and 3.55%, respectively. In other words, compared with the comparative example, Examples 1 and 2 show excellent accuracy, and in particular, Example 1 achieves excellent reproducibility with an accuracy of 0.55%.

[0079] Precision was calculated as the percentage of the standard deviation value relative to the mean value of the electrode resistance.

[0080] Although the embodiments according to the present disclosure have been described above, they are merely illustrative, and those skilled in the art will appreciate that various modifications and embodiments of equivalent scopes may be made therefrom. Therefore, the true technical protection scope of the present disclosure should be determined by the appended claims.

[0081] <Explanation of symbols> 11...Measurement target electrode, 100...Upper terminal, 110...First GDL, 111...Microporous layer, 112...Carbon fiber layer, 120...Conductive paste, 130...Conductive pressure plate, 140...Load body, 150...Conductive cable, 200...Lower terminal, 210...Second GDL, 211...Microporous layer, 212...Carbon fiber layer, 220...Conductive paste, 230...Conductive support plate, 300...Resistance measurement unit

[0082] Industrial Applicability

[0083] The electrode resistance measurement apparatus of the present disclosure measures the through-plane resistance of an electrode, which can achieve monolithic measurement of individual electrodes with high reproducibility.

[0084] The electrode resistance measuring apparatus of the present disclosure can minimize the contact resistance between the electrode and the terminal when measuring the through-plane resistance.

[0085] The electrode resistance measuring device of the present disclosure can obtain the resistance measurement value of the individual electrode in a state where the contact resistance is minimized by forming a microporous conductive layer on the surface of the terminal that contacts the electrode and completely adhering to the rough surface of the individual electrode.

Claims

1. An electrode resistance measuring device, comprising: an upper terminal, the bottom surface of which is in close contact with the upper surface of the measurement target electrode; a lower terminal, the upper surface of which is in close contact with the lower surface of the measurement target electrode; as well as a resistance measuring unit electrically connected to the upper terminal and the lower terminal to measure the resistance of the measurement target electrode, Wherein a microporous layer is formed on the bottom surface of the upper terminal and the upper surface of the lower terminal.

2. The electrode resistance measuring device according to claim 1, wherein: The material of the microporous layer includes at least one of carbon, conductive metal and conductive polymer.

3. The electrode resistance measuring device according to claim 1, wherein: The microporous layer of the upper terminal is formed by D 50 The fine particles with a width of 5 μm or less or the fine fiber web with a width of 10 μm or less are coated or bonded to the bottom surface of the conductive pressure plate made of a rigid material, The microporous layer of the lower terminal is also formed by D 50 The conductive support plate is formed by coating or bonding fine particles with a diameter of 5 μm or less or a fine fiber web with a width of 10 μm or less to the upper surface of the conductive support plate made of a rigid material, and The material of the fine particles or the fine fiber web coated or bonded to the upper terminal and the lower terminal includes at least one of transition metal, aluminum, carbon, and a conductive polymer.

4. The electrode resistance measuring device according to claim 1, wherein: The upper terminal comprises: a conductive pressure plate made of a conductive material and having a bottom surface formed as a plane perpendicular to the vertical direction; and a first gas diffusion layer (GDL) fixed to the bottom surface of the conductive pressure plate, and The lower terminal comprises: a conductive support plate made of a conductive material and having an upper surface formed as a plane perpendicular to the vertical direction; and a second GDL, the second GDL being fixed to the upper surface of the conductive support plate, and The conductive paste fixes the first GDL and the conductive pressure plate between the first GDL and the conductive pressure plate and fixes the second GDL and the conductive support plate between the second GDL and the conductive support plate.

5. The electrode resistance measuring device according to claim 4, wherein: The material of the conductive pressure plate and the conductive support plate includes at least one of transition metals, aluminum, and carbon on the periodic table.

6. The electrode resistance measuring device according to claim 4, wherein: The first GDL and the second GDL include the microporous layer and a carbon fiber layer.

7. The electrode resistance measuring device according to claim 6, wherein: the upper surface of the carbon fiber layer of the first GDL is adhered to the bottom surface of the conductive pressure plate through the conductive paste, In the first GDL, the microporous layer is stacked on a bottom surface of the carbon fiber layer, The bottom surface of the carbon fiber layer of the second GDL is adhered to the upper surface of the conductive support plate through the conductive paste, and In the second GDL, the microporous layer is stacked on an upper surface of the carbon fiber layer.

8. The electrode resistance measuring device according to claim 7, wherein: The conductive paste is obtained by mixing conductive particles, a binder and a solvent in a paste state. The conductive particles of the conductive paste include at least one of carbon black, graphite, CNT, graphene, transition metal and aluminum, and The conductive particles of the conductive paste have a size of 20 μm or less. 50 .

9. The electrode resistance measuring device according to claim 8, wherein: The conductive paste is formed to a thickness of 20 μm to 200 μm between the first GDL and the conductive pressure plate and between the second GDL and the conductive support plate.

10. The electrode resistance measuring device according to claim 7, wherein: The porosity of the microporous layer of the first GDL and the microporous layer of the second GDL is 30% to 80%.

11. The electrode resistance measuring device according to claim 7, wherein: The microporous layer of the first GDL and the microporous layer of the second GDL have a thickness of 20 μm to 150 μm.

12. The electrode resistance measuring device according to claim 3, wherein: A support body for pressing the measurement target electrode is stacked on an upper surface of the upper terminal.

13. The electrode resistance measuring device according to claim 12, wherein: Each of the upper terminal and the load body is provided in a disk shape.

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