Integrated three-electrode device

Abstract

The utility model discloses an integrated three-electrode device, including a diaphragm, a third electrode and a tab; one end of the third electrode is fixedly connected to the diaphragm, and the other end of the third electrode is fixedly connected to the tab. The utility model connects the tab to the electrode, and during the test process, the tab can be directly connected to the three-battery test system, and no additional electrode implantation steps are required during the test process. The test process is simple, less subjective, and the data continuity and stability are better; in addition, the structure has better adaptability to automated testing, which is conducive to continuous automated testing in mass production.

Description

Technical Field

[0001] The utility model relates to an integrated three-electrode device, belonging to the field of lithium batteries. Background Art

[0002] As an important component of modern industry, the performance of lithium-ion batteries has a significant impact on the performance of equipment. Lithium-ion batteries often decay during use, and their capacity decay is generally caused by the decay of positive or negative electrode materials. In the process of battery design optimization, it is particularly important to understand the battery decay mechanism. At present, the analysis of electrode decay mainly adopts the three-electrode method. The general steps are to disassemble the failed battery, take out the positive and negative electrode sheets, and then prepare them into half-button batteries respectively. The button half-battery is used as the working electrode and lithium metal is used as the counter electrode to realize the three-electrode test.

[0003] There are several disadvantages in the above-mentioned testing process. First, this method requires the battery to be disassembled during the test, and the implantation process is very cumbersome. Second, the test is generally performed after the battery fails, and its test state is relatively fixed, making it impossible to perform in-situ analysis. The test results have large deviations when used as engineering references, which increases the difficulty of analysis for engineers. Utility Model Content

[0004] In order to solve the technical problems in the above-mentioned background technology that the test is complicated and in-situ analysis cannot be performed, the utility model provides an integrated three-electrode device.

[0005] The technical solution for achieving the purpose of the utility model is an integrated three-electrode device, including a diaphragm, a third electrode and a tab; one end of the third electrode is fixedly connected to the diaphragm, and the other end of the third electrode is fixedly connected to the tab.

[0006] The utility model connects the pole ear with the electrode, and during the test process, the pole ear can be directly connected to the three-battery test system. There is no need to perform additional electrode implantation steps during the test process, and the test process is simple, less subjectivistic, and has better data continuity and stability. In addition, the structure has better adaptability to automated testing, which is beneficial to continuous automated testing in mass production processes.

[0007] In order to meet the material compatibility requirement, one end of the third electrode is bonded and fixed to the diaphragm.

[0008] In order to meet the requirements of material compatibility and conductivity, the other end of the third electrode is fixed to the electrode tab by welding.

[0009] In order to improve the adhesion of the diaphragm, the diaphragm is a glue-coated diaphragm. In the actual production process, a finished diaphragm can be used for packaging. It is only necessary to ensure that the third electrode is stably fixed on the diaphragm.

[0010] The third electrode has a diameter of 10-100 um and is made of platinum, copper, silver, gold, nickel, iron or an alloy thereof. The battery thickness and capacity parameters are calculated during the specific parameter design process to meet the test requirements.

[0011] The diaphragm is polyvinylidene fluoride or polyacrylic acid film, the coating thickness is 1~1000um, and the film thickness is 5~16um. The above two materials have good solvent resistance and acid and alkali corrosion resistance, and better durability in the battery electrolyte environment. Controlling the coating thickness and film thickness can effectively control the overall thickness of the battery, taking into account various parameter requirements in the battery production process.

[0012] In order to optimize welding stability, the tab of the third electrode is a nickel strip.

[0013] In order to obtain the optimal cost parameters, the Tab Thickness 0.1~1mm, length 10~20cm.

[0014] By adopting the above technical solution, the utility model has the following beneficial effects:

[0015] The utility model connects the pole ear with the electrode, and during the test process, the pole ear can be directly connected to the three-battery test system. There is no need to perform additional electrode implantation steps during the test process, and the test process is simple, less subjectivistic, and has better data continuity and stability. In addition, the structure has better adaptability to automated testing, which is beneficial to continuous automated testing in mass production processes.

[0016] One end of the third electrode of the utility model is bonded and fixed to the diaphragm, and the material compatibility is better.

[0017] The other end of the third electrode of the utility model is welded and fixed to the pole ear, so as to obtain better material compatibility and conductive performance.

[0018] The utility model adopts a glue-coated diaphragm, and the diaphragm has better adhesion.

[0019] The diaphragm of the utility model is polyvinylidene fluoride or polyacrylic acid film, the coating thickness is 1~1000um, the film thickness is 5~16um, it has good solvent resistance and acid and alkali corrosion resistance, and better durability in the battery electrolyte environment. Controlling the coating thickness and the film thickness can effectively control the overall thickness of the battery, taking into account various parameter requirements in the battery production process.

[0020] The pole ear of the third electrode of the utility model is a nickel strip, which can obtain better welding stability.

[0021] The utility model controls the thickness of the pole ear to be 0.1-1 mm and the length to be 10-20 cm, and has a better cost advantage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to specific embodiments and in conjunction with the accompanying drawings.

[0023] Figure 1 It is a structural schematic diagram of the utility model.

[0024] The reference numerals in the accompanying drawings are:

[0025] Separator 1, third electrode 2, nickel strip 3. DETAILED DESCRIPTION

[0026] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0030] In the description of the embodiments of the present utility model, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present utility model.

[0031] In the description of the embodiments of the present utility model, it is also necessary to explain that, unless otherwise clearly stipulated and limited, the terms "set", "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. The utility model is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the scope of protection of the utility model.

[0032] (Example 1)

[0033] See Figure 1 The integrated three-electrode device of this embodiment includes a diaphragm 1, a third electrode 2 and a tab 3; one end of the third electrode 2 is fixedly connected to the diaphragm 1, and the other end of the third electrode 2 is fixedly connected to the tab 3.

[0034] When in use, the pole ear can be connected to the circuit to be tested for testing. After the test is completed, the pole ear can be packaged with electrical tape, and then the battery can be returned to the original working environment for continued use. After a certain interval, it can be taken out and tested again. In this way, there is no need to destroy the battery structure during the test, and a large number of batteries can be tested in a certain time series. The data stability and availability have great advantages over disassembling the battery for testing.

[0035] One end of the third electrode 2 is bonded and fixed to the diaphragm 1 ; the other end of the third electrode 2 is welded and fixed to the tab.

[0036] The diaphragm 1 is a rubber-coated diaphragm and can be installed during the battery rolling or packaging process.

[0037] The third electrode 2 has a diameter of 10um and is made of nickel strip, with a thickness of 0.1-1mm and a length of 10-20cm. Nickel metal has certain advantages in weldability compared to other materials. In specific production, platinum, copper, silver, gold, iron or their alloys can be used to replace nickel metal.

[0038] The diaphragm 1 is a polyvinylidene fluoride or polyacrylic acid film, with a coating thickness of 200um and a film thickness of 16um. During the preparation process, it can be adjusted according to the battery size parameters as long as the performance requirements are met.

[0039] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An integrated three-electrode device, characterized in that: It comprises a diaphragm (1), a third electrode (2) and a pole lug (3); one end of the third electrode (2) is fixedly connected to the diaphragm (1), and the other end of the third electrode (2) is fixedly connected to the pole lug (3).

2. The integrated three-electrode device according to claim 1, characterized in that: One end of the third electrode (2) is bonded and fixed to the diaphragm (1).

3. The integrated three-electrode device according to claim 1, characterized in that: The other end of the third electrode (2) is welded and fixed to the electrode tab.

4. The integrated three-electrode device according to claim 1, characterized in that: The diaphragm (1) is a rubber-coated diaphragm.

5. The integrated three-electrode device according to claim 2, characterized in that: The diaphragm (1) is a polyvinylidene fluoride or polyacrylic acid film, the coating thickness is 1-1000 um, and the film thickness is 5-16 um.

6. The integrated three-electrode device according to claim 3, characterized in that: The pole lug (3) of the third electrode (2) is a nickel strip.

7. The integrated three-electrode device according to claim 5, characterized in that: The tab (3) has a thickness of 0.1-1 mm and a length of 10-20 cm.

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