CN-122029436-A - Method for measuring the resistance of a target electrode and electrode device for carrying out the method

CN122029436ACN 122029436 ACN122029436 ACN 122029436ACN-122029436-A

Abstract

A method and an electronic device for measuring a resistance of a target electrode are disclosed, the method including the steps of acquiring a graph related to a conductivity of the target electrode changed according to a frequency after the target electrode has been immersed in an electrolyte for a predetermined time or more, determining a first point and a second point on a conductivity graph of the target electrode, the graph being included in the graph, and measuring the resistance of the target electrode based on the first point and the second point.

Inventors

PU ZHIHUI
JIN JIONGSHI
Zhao Hena

Assignees

株式会社LG新能源

Dates

Publication Date: 20260512
Application Date: 20241101
Priority Date: 20240419

Claims (10)

1. A method for measuring resistance of a target electrode, the method comprising: acquiring a graph of the conductivity of the target electrode, which is changed according to frequency, after the target electrode is impregnated with the electrolyte solution for a predetermined time or more; determining a first point of a conductivity profile of the target electrode and a second point of the conductivity profile included in the graph, and The resistance of the target electrode is measured based on the first point and the second point.
2. The method of claim 1, wherein the plot of the conductivity of the target electrode comprises: A first axis for the real part of the conductivity of the target electrode, and A second axis for an imaginary part of the electrical conductivity of the target electrode, the second axis being perpendicular to the first axis.
3. The method of claim 2, wherein the determining comprises determining an intersection of the first axis of the conductivity graph for the real part and the conductivity graph as the first point and an inflection point of the conductivity graph according to an increase in frequency as the second point, and The measuring includes: Measuring a first resistance based on a reciprocal value of a first conductivity at the first point of the conductivity graph, and A second resistance is measured based on a difference between a reciprocal value of a second conductivity at the second point of the conductivity graph and a reciprocal value of the first conductivity at the first point.
4. The method of claim 3, wherein the resistance of the target electrode is determined based on a sum of the electronic resistance of the target electrode and the ionic resistance of the target electrode, and The electronic resistance of the target electrode is the first resistance, and the ionic resistance of the target electrode is the second resistance.
5. The method of claim 1, further comprising: acquiring the resistance of the reference cell, and Verifying that the target electrode is a normal electrode when a difference between the resistance of the reference cell and the resistance of the target electrode is below a threshold, and The reference cell includes at least one or more target electrodes and is impregnated with the electrolyte solution for a predetermined time or more.
6. The method of claim 1, wherein the conductivity of the target electrode that varies according to the frequency is acquired using broadband dielectric spectroscopy.
7. The method according to claim 1, wherein the process of impregnating the target electrode is a process of impregnating the target electrode for a predetermined time or longer after injecting the electrolyte solution into the electrode holder in a state where the target electrode is inserted inside the electrode holder, The electrode holder includes: A cylindrical upper plate, and A cylindrical lower plate having a recess into which the upper plate is to be inserted, The inner wall of the recess of the lower plate comprises polytetrafluoroethylene, and The target electrode is interposed between the upper plate and the lower plate of the electrode holder.
8. The method of claim 3, wherein the first and second resistances are determined inversely proportional to a conductive material content of an entire active material layer of the target electrode including active material, conductive material, and binder.
9. A non-transitory computer-readable recording medium in which a program for executing the method according to any one of claims 1 to 8 on a server is recorded.
10. An electronic device, comprising: A memory configured to store instructions, and A processor, said processor being connected to said memory, Wherein the processor is configured to: acquiring a graph of the conductivity of the target electrode, which is changed according to frequency, after the target electrode is impregnated with the electrolyte solution for a predetermined time or more; determining a first point of a conductivity profile of the target electrode and a second point of the conductivity profile included in the graph, and The resistance of the target electrode is measured based on the first point and the second point.

Description

Method for measuring the resistance of a target electrode and electrode device for carrying out the method Technical Field The present disclosure relates to a method and an electronic device for measuring a resistance of a target electrode. Background Conductivity within an electrode is one of the factors affecting battery performance, and accurate prediction of conductivity parameters of an electrode is an essential element required to enhance the performance of a battery model. The most widely used method for measuring the electrical conductivity of a lithium secondary battery, which has high energy density and operating potential, long cycle life and low self-discharge rate, is mainly a method of measuring the probe resistance or vertical resistance of a dry electrode. Since an actual battery is operated while being impregnated with an electrolyte solution, various studies have been directed to accurately measuring conductivity under actual driving conditions and when an electrode is dried, and obtaining information required for battery operation. Disclosure of Invention Technical object A technical object of the present disclosure according to example embodiments is to measure conductivity of an electrode according to a frequency change of a target electrode impregnated with an electrolyte solution using Broadband Dielectric Spectroscopy (BDS), analyze a graph of the conductivity of the electrode according to the frequency change, and measure resistance of the target electrode according to a resistance value determined based on a predetermined region of the graph. Further, another technical object of the present disclosure according to example embodiments is to determine whether a manufactured battery is a normal electrode falling within a range in which the battery can normally operate while being impregnated with an actual electrolyte solution by verifying an electrode having a predetermined specification before manufacturing a complete product at an early stage. The objects to be achieved by the exemplary embodiments of the present disclosure are not limited to the above-described objects, and other objects may be inferred from the following exemplary embodiments. Technical proposal According to one aspect, there is provided a method for measuring a resistance of a target electrode, the method including acquiring a graph of a conductivity of the target electrode changed according to a frequency after the target electrode is impregnated with an electrolyte solution for a predetermined time or more, determining a first point of the conductivity graph and a second point of the conductivity graph of the target electrode included in the graph, and measuring the resistance of the target electrode based on the first point and the second point. The graph of the conductivity of the target electrode may include a first axis for the real part of the conductivity of the target electrode and a second axis for the imaginary part of the conductivity of the target electrode, the second axis being perpendicular to the first axis. The determining may include determining an intersection of a first axis of the conductivity graph for the real part and the conductivity graph as a first point and an inflection point of the conductivity graph according to the frequency increase as a second point, and the measuring may include measuring the first resistance based on a reciprocal value of the first conductivity at the first point of the conductivity graph and measuring the second resistance based on a difference between the reciprocal value of the second conductivity at the second point of the conductivity graph and the reciprocal value of the first conductivity at the first point. The resistance of the target electrode may be determined based on a sum of an electronic resistance of the target electrode and an ionic resistance of the target electrode, and the electronic resistance of the target electrode may be a first resistance and the ionic resistance of the target electrode may be a second resistance. The method may further include acquiring a resistance of the reference battery cell, and verifying that the target electrode is a normal electrode when a difference between the resistance of the reference battery cell and the resistance of the target electrode is below a threshold value, and the reference battery cell may include at least one or more target electrodes and may be impregnated with the electrolyte solution for a predetermined time or more. The conductivity of the target electrode, which varies according to frequency, can be obtained using broadband dielectric spectroscopy. The process of impregnating the target electrode may be a process of impregnating the target electrode for a predetermined time or more after injecting the electrolyte solution into the electrode holder while the target electrode is inserted inside the electrode holder, and the electrode holder may include a cylindrical upper plate, a cylindr