Electrode resistance measuring device

Abstract

The present invention relates to an electrode resistance measuring device, and provides an electrode resistance measuring device that enables measurement of individual electrodes with high reproducibility when measuring the through-plane resistance of an electrode.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0178973 dated December 20, 2022, and all contents disclosed in the documents of said Korean patent application are incorporated by reference into this specification.

[0002] The present invention relates to an electrode resistance measuring device, and more particularly to an electrode resistance measuring device that enables measurement of individual electrodes with high reproducibility when measuring the through-plane resistance of an electrode. [Background technology]

[0003] Methods for measuring the resistance of electrodes or auxiliary materials manufactured for secondary batteries, fuel cells, etc. are divided into in-plane resistance measurement and through-plane resistance measurement.

[0004] In fact, the through-plane resistance of the electrode, which coincides with the direction of electron flow when the battery is in operation, is directly related to the performance of the battery.

[0005] In addition, the through-plane resistance measurement can be used to grasp the vertical non-uniformity of electrodes coated by a wet coating method, and can be applied to battery quality control.

[0006] 1, the conventional through-plane resistance measurement is performed by closely contacting both sides of an electrode 1011 with a pair of terminals 1101 and 1102 for measuring the resistance of the electrode 1011, applying a current to both terminals 1101 and 1102 through a power supply 1200, and measuring the resistance. The terminals 1101 and 1102 for measuring the resistance of the electrodes may have flat contact portions. In this case, the high contact resistance between the electrode 1011 and the terminals 1101 and 1102 reduces the reproducibility of the through-plane resistance measurement.

[0007] In the past, in order to improve the reproducibility of through-plane resistance measurement, a method was used in which multiple electrodes were stacked and then pressed with high pressure. This measurement method also had difficulties in obtaining uniform values ​​due to the accumulated contact resistance between multiple electrodes and between the outermost electrode and the terminal, and contact non-uniformity due to steps, etc. Furthermore, analysis methods performed by stacking multiple electrodes had difficulties in analyzing the characteristics of individual electrodes.

[0008] There is a need for a surface transmission resistance measurement technique that can solve the above problems, has excellent reproducibility, and is capable of measuring individual electrodes. Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention relates to an electrode resistance measuring device, and an object of the present invention is to provide an electrode resistance measuring device which, when measuring the through-plane resistance of an electrode, enables measurement of individual electrodes one by one with high reproducibility.

[0010] The technical problems that the present invention aims to solve are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0011] The electrode resistance measuring device of the present invention includes an upper terminal whose bottom surface is in close contact with an upper surface of an electrode to be measured; a lower terminal whose top surface is in close contact with a lower surface of the electrode to be measured; and a resistance measuring unit electrically connected to the upper and lower terminals to measure the resistance of the electrode to be measured; and a microporous layer is formed on the bottom surface of the upper terminal and the top surface of the lower terminal. Effect of the Invention

[0012] The electrode resistance measuring device of the present invention measures the through-plane resistance of an electrode, and enables measurement of individual electrodes one by one with high reproducibility.

[0013] The electrode resistance measuring device of the present invention can minimize the contact resistance between the electrodes and the terminals when measuring through-plane resistance.

[0014] The electrode resistance measuring device of the present invention is capable of obtaining a resistance measurement value for an individual electrode with minimized contact resistance by forming a microporous conductive layer on the surface of a terminal that contacts the electrode and is in perfect contact with the rough surface of the individual electrode. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing a conventional method for measuring through-plane resistance. [Diagram 2] 1 is a perspective view showing an embodiment of an electrode resistance measuring device of the present invention. [Diagram 3] 4 is a cross-sectional view showing a state in which an upper terminal and a lower terminal are in close contact with an electrode to be measured. FIG. [Figure 4] FIG. 4 is a perspective view showing another embodiment of the electrode resistance measuring device of the present invention. [Diagram 5] 1 is a graph showing measured values ​​of through-plane resistance according to Example 1, Example 2, and a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The electrode resistance measuring device of the present invention includes an upper terminal whose bottom surface is in close contact with an upper surface of an electrode to be measured; a lower terminal whose top surface is in close contact with a lower surface of the electrode to be measured; and a resistance measuring unit electrically connected to the upper terminal and the lower terminal to measure the resistance of the electrode to be measured; and a microporous layer is formed on the bottom surface of the upper terminal and the top surface of the lower terminal.

[0017] In the electrode resistance measuring device of the present invention, the material of the microporous layer contains at least one of carbon, a conductive metal, and a conductive polymer.

[0018] In the electrode resistance measuring device of the present invention, the microporous layer of the upper terminal is provided with a conductive pressure plate made of a rigid material and a bottom surface of the conductive pressure plate.50 The microporous layer of the lower terminal is also formed by coating or bonding a fine particle having a diameter of 5 μm or less or a fine fiber network having a width of 10 μm or less on the upper surface of a conductive support plate made of a rigid material. 50 The upper terminal and the lower terminal are formed by coating or bonding fine particles having a diameter of 5 μm or less or a fine fiber network having a width of 10 μm or less, and the material of the fine particles or fine fiber network coated or bonded to the upper terminal and the lower terminal includes at least one of transition metal, aluminum, carbon, and conductive polymer.

[0019] In the electrode resistance measuring device of the present invention, the upper terminal includes a conductive pressure plate made of a conductive material and having a bottom surface formed on a plane perpendicular to the vertical direction, and a first GDL (gas diffusion layer) fixed to the bottom surface of the conductive pressure plate, and the lower terminal includes a conductive support plate made of a conductive material and having a top surface formed on a plane perpendicular to the vertical direction, and a second GDL fixed to the top surface of the conductive support plate, and the first GDL and the conductive pressure plate and the second GDL and the conductive support plate are fixed with a conductive paste.

[0020] In the electrode resistance measuring device of the present invention, the conductive pressure plate and the conductive support plate are made of materials containing at least one of a transition metal on the periodic table, aluminum, and carbon.

[0021] In the electrode resistance measuring device of the present invention, the first GDL and the second GDL each include a microporous layer and a carbon fiber layer.

[0022] In the electrode resistance measuring device of the present invention, the upper surface of the carbon fiber layer of the first GDL is adhered to the bottom surface of the conductive pressure plate by the conductive paste, a microporous layer is laminated on the bottom surface of the carbon fiber layer of the first GDL, the bottom surface of the carbon fiber layer of the second GDL is adhered to the upper surface of the conductive support plate by the conductive paste, and a microporous layer is laminated on the upper surface of the carbon fiber layer of the second GDL.

[0023] In the electrode resistance measuring device of the present invention, the conductive paste is obtained by mixing conductive particles, a binder and a solvent in a kneaded state, the material of the conductive particles of the conductive paste includes at least one of carbon black, graphite, CNT, graphene, a transition metal and aluminum, and the size of the conductive particles of the conductive paste is D 50 is also less than 20 μm.

[0024] In the electrode resistance measuring device of the present invention, the conductive paste is formed to a thickness of 20 to 200 μm between the first GDL and the conductive pressure plate, and between the second GDL and the conductive support plate.

[0025] In the electrode resistance measuring device of the present invention, the microporous layer of the first GDL and the microporous layer of the second GDL each have a porosity of 30 to 80%.

[0026] In the electrode resistance measuring device of the present invention, the microporous layer of the first GDL and the microporous layer of the second GDL each have a thickness of 20 to 150 μm.

[0027] In the electrode resistance measuring device of the present invention, a load body for applying pressure to the measurement target electrode is stacked on an upper surface of the upper terminal.

[0028] In the electrode resistance measuring device of the present invention, the upper terminal and the load body are disk-shaped.

[0029] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this process, the size and shape of components shown in the drawings may be exaggerated for clarity and convenience of explanation. Furthermore, terms specifically defined in consideration of the configuration and operation of the present invention may vary depending on the intention or practice of a user or operator. The definition of such terms should be based on the overall content of this specification.

[0030] In describing the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," "one side," "other side," and the like are based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships typically arranged when the product of the present invention is used, and are merely for the purpose of describing and briefly explaining the present invention, and do not present or imply that the displayed devices or elements must necessarily have a specific orientation, be configured or operated in a specific orientation, and should not be understood as limiting the present invention.

[0031] Fig. 2 is a perspective view showing one embodiment of the electrode resistance measuring device of the present invention. Fig. 3 is a cross-sectional view showing a state in which an upper terminal 100 and a lower terminal 200 are in close contact with a measurement target electrode 11. Fig. 4 is a perspective view showing another embodiment of the electrode resistance measuring device of the present invention. Fig. 5 is a graph showing through-plane resistance measurements according to Examples 1 and 2 and a comparative example.

[0032] The electrode resistance measuring device of the present invention will be described in detail below with reference to Figures 2 to 5. In the following description, the up and down direction is also the direction of gravity.

[0033] The electrode resistance measuring device of the present invention is capable of measuring the through-plane resistance of a single electrode with high reproducibility.

[0034] As shown in FIG. 2, the electrode resistance measuring device of the present invention includes an upper terminal 100, the bottom surface of which is in close contact with the top surface of the electrode 11 to be measured; a lower terminal 200, the top surface of which is in close contact with the bottom surface of the electrode 11 to be measured; and a resistance measuring unit 300 that is electrically connected to the upper terminal 100 and the lower terminal 200 to measure the resistance of the electrode 11 to be measured. Microporous layers 111, 211 are also formed on the bottom surface of the upper terminal 100 and the top surface of the lower terminal 200.

[0035] In the electrode resistance measuring device of the present invention, the electrode 11 to be measured is a plane perpendicular to the up-down direction. Specifically, the electrode 11 to be measured is a conductive material in the form of a plate or sheet. For example, the electrode 11 to be measured may be formed by applying an electrode slurry to a copper foil (Cu foil) or an aluminum foil (Al foil) and then drying the applied electrode slurry. The electrode slurry may be obtained by mixing an active material, a conductive material, a binder, and a solvent in a kneaded state, or may be obtained by mixing a conductive material, a binder, and a solvent in a kneaded state in order to improve the adhesive force between an electrode containing an active material and a conductive foil (foil) as a current collector. In this case, the surface on which the electrode slurry is dried may be rough depending on the circumstances and not ideally flat.

[0036] 2 and 4, the area of ​​the bottom surface of the upper terminal 100 or the top surface of the lower terminal 200 may be formed to be equal to or smaller than the area of ​​the electrode 11 to be measured. In the electrode resistance measuring device of the present invention, the bottom surface of the upper terminal 100 and the top surface of the lower terminal 200 are formed of microporous layers 111, 211, and the thickness of the electrode 11 to be measured is formed to be very thin. Therefore, if the area of ​​the bottom surface of the upper terminal 100 and the area of ​​the top surface of the lower terminal 200 are formed to be larger than the area of ​​the electrode 11 to be measured, the upper terminal 100 and the lower terminal 200 may come into direct contact with each other. Therefore, it is preferable that the area of ​​the bottom surface of the upper terminal 100 or the top surface of the lower terminal 200 is formed to be equal to or smaller than the area of ​​the electrode 11 to be measured.

[0037] In the electrode resistance measuring device of the present invention, the microporous layer 111, 211 may 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 forming the microporous layer 111, 211 after drying and heat treatment may be obtained by mixing carbon powder, fluororesin, water and alcohol.

[0038] The resistance measuring unit 300 of the present invention 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 AC or DC, and may be changed depending on the purpose of analysis. The resistance measuring unit 300 is electrically connected to each of the upper terminal 100 and the lower terminal 200 through a current carrying cable 150.

[0039] As shown in FIG. 3, in the electrode resistance measuring device of the present invention, the upper terminal 100 includes a conductive pressure plate 130 made of a conductive material and having a bottom surface formed on a plane perpendicular to the vertical direction, and a first GDL 110 fixed to the bottom surface of the conductive pressure plate 130, and the lower terminal 200 includes a conductive support plate 230 made of a conductive material and having an top surface formed on a plane perpendicular to the vertical direction, and a second GDL 210 fixed to the top surface of the conductive support plate 230.

[0040] The first GDL 110 and the conductive pressure plate 130 , and the second GDL 210 and the conductive support plate 230 are fixed to each other by conductive paste 120 , 220 .

[0041] In the electrode resistance measuring device of the present invention, the conductive pressure plate 130 and the first GDL 110, and the conductive support plate 230 and the second GDL 210, which are made of different materials, are fixed with the conductive pastes 120 and 220, thereby preventing a change in their relative positions, and filling gaps at the interface between them with the conductive pastes 120 and 220 to prevent a change in contact condition at the interface. Specifically, the conductive paste 120 is applied to the bottom surface of the conductive pressure plate 130 or the top surface of the first GDL, and then the conductive pressure plate 130 and the first GDL 110 are 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, the conductive paste 220 is applied between the conductive support plate 230 and the second GDL 210, and then the conductive support plate 230 and the second GDL 210 are 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.

[0042] The conductive pressure plate 130 and the conductive support plate 230 are made of at least one of transition metals on the periodic table, aluminum, and carbon. For example, the transition metal may be SUS, copper, titanium, nickel, etc. As another example, the conductive pressure plate 130 and the conductive support plate 230 are made of a rigid material coated with a conductive material such as silver. That is, the conductive pressure plate 130 and the conductive support plate 230 are made of a rigid conductive material. The conductive pressure plate 130 and the conductive support plate 230 are arranged so that the bottom surface of the conductive pressure plate 130 and the top surface of the conductive support plate 230 face each other, and the conductive pressure plate 130 is pressed downward with the measurement target electrode 11 sandwiched between them to be in close contact with the measurement target electrode 11.

[0043] The first GDL 110 and the second GDL 210 include a microporous layer 111, 211 and a carbon fiber layer 112, 212. As described above, the first GDL 110 and the second GDL 210 may be provided by applying a carbon paste to a carbon fiber layer 112, 212 such as carbon paper, and then drying and heat-treating the carbon paste to form the microporous layer 111, 211. The carbon paste that forms the microporous layer 111, 211 after drying and heat-treating may be obtained by mixing carbon powder, fluororesin, water, and alcohol. The fluororesin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkylvinylether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (ETFE), and polyfluorovinylidene (PVDF).

[0044] The carbon fiber layers 112, 212 are made of carbon fiber. The carbon fiber (CF) is a fibrous carbon material with a mass content of carbon element of 90% or more. Specifically, the carbon fiber is a fiber having a graphite structure obtained by pyrolysis of an organic precursor (a material before carbonization). The carbon fiber layers 112, 212 are coated with a fluororesin.

[0045] As shown in FIG. 3, the upper surface of the carbon fiber layer 112 of the first GDL 110 is adhered to the bottom surface of the conductive pressure plate 130 by the conductive paste 120, and a microporous layer 111 is laminated 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 is adhered to the upper surface of the conductive support plate 230 by the conductive paste 220, and a microporous layer 211 is laminated on the upper surface of the carbon fiber layer 212 of the second GDL 210. That is, in the electrode resistance measuring device of the present invention, the carbon fiber layers 112, 212 of the GDL are bonded with conductive pastes 120, 220 to the conductive pressure plate 130 and the conductive support plate 230, which are made of a material that has high quality smoothness and is easy to form into a flat surface, and the microporous layers 111, 211 of the GDL are brought into close contact with the surface of the electrode 11 to be measured, which has less smoothness, thereby minimizing the contact resistance and improving the reproducibility when measuring the surface transmission resistance.

[0046] The conductive paste 120, 220 is obtained by mixing conductive particles, a binder, and a solvent in a kneaded state. The material of the conductive particles of the conductive paste 120, 220 includes 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 is D 50 is also less than 20 μm.

[0047] The conductive pastes 120, 220 are formed to a thickness of 20 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, 220 is determined in consideration of the condition of the carbon fiber layers 112, 212 or the smoothness of the conductive pressure plate 130 and the conductive support plate 230.

[0048] The porosity of the microporous layer 111 of the first GDL 110 and the microporous layer 211 of the second GDL 210 is 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 is 40 to 70%. The thickness of the microporous layer 111 of the first GDL 110 and the microporous layer 211 of the second GDL 210 is 20 to 150 μm.

[0049] In another embodiment, the microporous layer of the top terminal is bonded to the bottom surface of the rigid conductive pressure plate. 50 The microporous layer of the lower terminal may be formed by coating or bonding a fine particle having a diameter of 5 μm or less or a fine fiber network having a width of 10 μm or less. In addition, the microporous layer of the lower terminal may be formed by coating or bonding a fine particle having a diameter of 5 μm or less or a fine fiber network having a width of 10 μm or less on the upper surface of the conductive support plate made of a rigid material. 50 The upper terminal and the lower terminal may be coated or bonded with a fine particle having a diameter of 5 μm or less or a fine fiber network having a width of 10 μm or less. In this case, the material of the fine particle or fine fiber network coated or bonded to the upper terminal and the lower terminal includes at least one of transition metal, aluminum, carbon, and conductive polymer.

[0050] As shown in FIG. 4, a load body 140 for applying pressure to the electrode 11 to be measured is also laminated on the upper surface of the upper terminal 100. A plurality of load bodies 140 may be provided. When measuring through-plane resistance, the magnitude of the pressure applied to the electrode 11 to be measured by the upper terminal 100 may affect the measurement result. Therefore, it is necessary to apply pressure to the electrode 11 to be measured at an appropriate level of pressure, and in the electrode resistance measuring device of the present invention, the number of load bodies 140 can be adjusted to adjust the pressure applied to the electrode 11 to be measured by the upper terminal 100. The pressure applied to the electrode 11 to be measured by the upper terminal 100 is 0.01 to 0.2 kgf / cm. 2 It is preferable that the pressure applied by the upper terminal 100 to the measurement target electrode 11 is 0.01 kgf / cm 2 If the pressure applied by the upper terminal 100 to the electrode 11 to be measured is less than 0.2 kgf / cm, the contact resistance increases and the measurement accuracy decreases. 2If it exceeds this value, the thickness of the electrode 11 to be measured may change, which may affect the measured value.

[0051] The upper terminal 100 and the load body 140 are disk-shaped. For accurate measurement using the electrode resistance measuring device of the present invention, it is important that the upper terminal 100 is not tilted. Therefore, the upper terminal 100 and the load body 140 may be disk-shaped so as not to have anisotropy in a direction perpendicular to the up-down direction. The upper terminal 100 may be provided with an alignment means for aligning the center of the load body 140 with the center of the upper terminal 100. The alignment means may be a protrusion, a groove, a marker, or the like. The current-carrying cable 150 for electrically connecting the upper terminal 100 and the resistance measuring unit 300 is laterally coupled to the upper terminal 100 so as not to interfere with the stacking of the load body 140.

[0052] Example 1 The positive electrode of the lithium secondary battery is the measurement target electrode 11, and the 2 It was prepared in the size of

[0053] The conductive pressure plate 130 and the conductive support plate 230 were made of SUS material, and were prepared so that the sum of the weights of the upper terminal 100 and the load body 140 was 0.3 kg. The first GDL 110 and the second GDL 210 were made of Sigracet 39 BC manufactured by SGL.

[0054] Conductive pastes 120, 220 were 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 were fixed to each other.

[0055] A Hioki BT3563 HiTESTER manufactured by Hioki Corporation was used as the resistance measuring unit 300. An AC current of 1 kHz was applied between the upper terminal 100 and the lower terminal 200 as an input current.

[0056] After the measurement target electrode 11 was completely separated from the upper terminal 100 and the lower terminal 200, the measurement was repeated three times.

[0057] Example 2 The positive electrode of the lithium secondary battery is the measurement target electrode 11, and the 2 It was prepared in the size of

[0058] The conductive pressure plate 130 and the conductive support plate 230 were made of SUS material, and were prepared so that the sum of the weights of the upper terminal 100 and the load body 140 was 0.3 kg. The first GDL 110 and the second GDL 210 were made of Sigracet 39 BC manufactured by SGL.

[0059] The conductive pressure plate 130 and the first GDL 110, and the conductive support plate 230 and the second GDL 210 are not fixed with a conductive paste but are directly attached to each other.

[0060] A Hioki BT3563 HiTESTER manufactured by Hioki Corporation was used as the resistance measuring unit 300. An AC current of 1 kHz was applied between the upper terminal 100 and the lower terminal 200 as an input current.

[0061] After the measurement target electrode 11 was completely separated from the upper terminal 100 and the lower terminal 200, the measurement was repeated three times.

[0062] Comparative Example The positive electrode of the lithium secondary battery is the measurement target electrode 11, and the 2 It was prepared in the size of

[0063] The conductive pressure plate 130 and the conductive support plate 230 were made of SUS material, and were prepared so that the sum of the weights of the upper terminal 100 and the load body 140 was 0.3 kg.

[0064] As shown in FIG. 1, direct contact was made between the conductive pressure plate 130 and the electrode 11 to be measured, and between the conductive support plate 230 and the electrode 11 to be measured, without the insertion of a GDL.

[0065] A Hioki BT3563 HiTESTER manufactured by Hioki Corporation was used as the resistance measuring unit 300. An AC current of 1 kHz was applied between the upper terminal 100 and the lower terminal 200 as an input current.

[0066] After the measurement target electrode 11 was completely separated from the upper terminal 100 and the lower terminal 200, the measurement was repeated three times.

[0067] The resistance values ​​shown in FIG. 5 are also average values ​​obtained by repeated measurements. As shown in FIG. 5, when the microporous layers 111, 211 are present on the surface of the terminal that contacts the electrode 11 to be measured in the through-plane resistance measurement, the measured resistance value is significantly reduced. In particular, it is seen that the measured resistance values ​​differ by about 50 times or more between Example 1 and Comparative Example. This is because the contact resistance that interferes with the measurement is minimized. Furthermore, the precisions of Example 1, Example 2, and Comparative Example were calculated to be 0.55%, 2.36%, and 3.55%, respectively. That is, Example 1 and Example 2 showed superior precision compared to the Comparative Example, and in particular, Example 1 had a precision of 0.55%, which embodied superior reproducibility.

[0068] The precision was calculated as a percentage of the standard deviation of the average electrode resistance.

[0069] Although the embodiment of the present invention has been described above, it is merely an example, and a person skilled in the art will understand that various modifications and equivalent embodiments are possible. Therefore, the true technical scope of the present invention should be determined by the claims. [Industrial Applicability]

[0070] The electrode resistance measuring device of the present invention measures the through-plane resistance of an electrode, and enables measurement of individual electrodes one by one with high reproducibility.

[0071] The electrode resistance measuring device of the present invention can minimize the contact resistance between the electrodes and the terminals when measuring through-plane resistance.

[0072] The electrode resistance measuring device of the present invention is capable of obtaining a resistance measurement value for an individual electrode with minimized contact resistance by forming a microporous conductive layer on the surface of a terminal that contacts the electrode and is in perfect contact with the rough surface of the individual electrode. [Explanation of symbols]

[0073] 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: Loaded body 150:Electrical cable 200: Lower terminal 210: 2nd GDL 211: Microporous layer 212: Carbon fiber layer 220: Conductive paste 230: Conductive support plate 300: Resistance measurement unit

Claims

1. an upper terminal whose bottom surface is in intimate contact with the upper surface of the electrode to be measured; a lower terminal whose upper surface is in intimate contact with the lower surface of the electrode to be measured; a resistance measuring unit electrically connected to the upper terminal and the lower terminal to measure a resistance of the measurement target electrode, the bottom surface of the upper terminal and the top surface of the lower terminal are provided with a microporous layer.

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

3. The microporous layer of the upper terminal is attached to the bottom surface of a rigid conductive pressure plate. ５０ The nanoparticles having a diameter of 5 μm or less or the nanofiber network having a width of 10 μm or less are coated or bonded to the nanoparticles, The microporous layer of the lower terminal is also formed on the upper surface of a conductive support plate of a rigid material. ５０ The nanoparticles having a diameter of 5 μm or less or the nanofiber network having a width of 10 μm or less are coated or bonded to the nanoparticles, 2 . The electrode resistance measuring device according to claim 1 , wherein the material of the fine particles or fine fiber network coated or bonded to the upper terminal and the lower terminal includes at least one of a transition metal, aluminum, carbon, and a conductive polymer.

4. The upper terminal is A conductive pressure plate made of a conductive material and having a bottom surface formed as a plane perpendicular to the up-down direction; a first GDL fixed to the bottom surface of the conductive pressure plate; The lower terminal is A conductive support plate made of a conductive material and having an upper surface formed as a plane perpendicular to the up-down direction; a second GDL secured to the top surface of the conductive support plate; 2. The electrode resistance measuring device according to claim 1, wherein the first GDL and the conductive pressure plate, and the second GDL and the conductive support plate are fixed with a conductive paste.

5. 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 a transition metal on the periodic table, aluminum, and carbon.

6. The electrode resistance measurement device of claim 4 , wherein the first GDL and the second GDL include a microporous layer and a carbon fiber layer.

7. an upper surface of the carbon fiber layer of the first GDL is bonded to a bottom surface of the conductive pressure plate by the conductive paste; A microporous layer is laminated on the bottom surface of the carbon fiber layer of the first GDL, a bottom surface of the carbon fiber layer of the second GDL is bonded to an upper surface of the conductive support plate by the conductive paste; 7. The electrode resistance measuring device according to claim 6, wherein a microporous layer is laminated on an upper surface of the carbon fiber layer of the second GDL.

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

9. 9. The electrode resistance measuring device according to claim 4, wherein the conductive paste is formed to a thickness of 20 to 200 μm between the first GDL and the conductive pressure plate, and between the second GDL and the conductive support plate.

10. 8. 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. 8. The electrode resistance measuring device according to claim 7, wherein the thickness of the microporous layer of the first GDL and the microporous layer of the second GDL is 20 to 150 μm.

12. 4. The electrode resistance measuring device according to claim 3, wherein a load body for applying pressure to the measurement target electrode is laminated on an upper surface of the upper terminal.

13. 13. The electrode resistance measuring device according to claim 12, wherein the upper terminal and the load body are disk-shaped.

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