Buckle type three-electrode device for testing electrical performance

Abstract

The embodiment of the utility model provides a buckle type three-electrode device for testing electrical performance, and relates to the field of three-electrode buckle type testing devices. The utility model aims to solve the problem that a test structure for the electrical performance of a battery is relatively complex. The buckle type three-electrode device for testing the electrical performance comprises a negative electrode shell, a steel sheet, a sealant layer, a reference electrode, a negative electrode sheet and a first diaphragm, wherein the negative electrode shell is provided with a first hole; the steel sheet and the cathode shell are bonded, fixed and isolated through a sealant layer, and the steel sheet seals the first hole; the reference electrode and the negative plate are sequentially fixed on one side, far away from the negative shell, of the steel plate, the reference electrode is connected with the steel plate, the first diaphragm is fixed between the negative plate and the reference electrode, and the negative plate is connected with the negative shell. The sealing glue layer separates the steel sheet from the negative shell while bonding the steel sheet and the negative shell, so that short circuit between the negative shell and the steel sheet is prevented, the structure is simple, and the sealing performance is good.

Description

Technical Field

[0001] The utility model relates to the field of three - electrode button - type test devices, and more specifically, to a button - type three - electrode device for testing electrical properties. Background Art

[0002] At present, lithium iron phosphate manganate has received wide attention from all sectors of society due to its high safety, low cost, long life, high energy density, etc. However, due to its complex crystal structure and diverse electrochemical reactions, more testing methods need to be developed to explore its failure mechanism and promote the rapid development of lithium iron phosphate manganate materials.

[0003] The existing soft - package three - electrode test technology has the following problems: high cost, low utilization rate of materials and components, large consumption of the outer shell, electrode sheets, separator, and electrolyte, and all of them are not recyclable, complex processes, requiring multiple personnel to be configured; complex sample preparation process, complex equipment, low success rate, easy breakage of copper wires, and easy to cause internal short - circuit of the battery; high operation difficulty and high requirements for test equipment.

[0004] Generally, a soft - package battery requires a positive - electrode area of about 25 cm 2 , a negative - electrode area of about 54 cm 2 (where the negative electrode is slightly larger than the positive electrode), a separator of about 216 cm 2 , 0.7 ML of electrolyte, and it cannot be recycled after the test; material mixing, coating, battery assembly, and testing all require professional operation, and the equipment is large, and the installation and use are more complex compared with button - type battery equipment; the soft - package battery needs to pre - bury thin copper wires as reference electrodes, which are easy to break during the test, and easy to pierce the separator to cause short - circuit, and the area for the supply of electrochemical reactions is small, which is likely to reduce the test accuracy. Summary of the Utility Model

[0005] The objectives of the present utility model include, for example, providing a button - type three - electrode device for testing electrical properties, which can improve the problem of the relatively complex test structure of battery electrical properties.

[0006] The embodiments of the present utility model can be implemented as follows:

[0007] The embodiments of the present utility model provide a button - type three - electrode device for testing electrical properties, including a negative - electrode shell, a steel sheet, a sealing glue layer, a reference electrode, a negative - electrode sheet, and a first separator. The negative - electrode shell is provided with a first hole; the steel sheet is adhesively fixed and isolated from the negative - electrode shell through the sealing glue layer, and the steel sheet seals the first hole; the reference electrode and the negative - electrode sheet are sequentially fixed on the side of the steel sheet away from the negative - electrode shell. The reference electrode is connected to the steel sheet, the first separator is fixed between the negative - electrode sheet and the reference electrode, and the negative - electrode sheet is connected to the negative - electrode shell.

[0008] In addition, the button-type three-electrode device for testing electrical properties provided by the embodiments of the present utility model may further have the following additional technical features:

[0009] Optionally, the sealant layer is provided with a second hole, and the second hole is coaxially arranged with the first hole.

[0010] Optionally, the aperture of the second hole is smaller than the aperture of the first hole.

[0011] Optionally, the reference electrode is a copper foil, and the copper foil is pressed on the side of the steel sheet away from the negative electrode case.

[0012] Optionally, the copper foil has a disc structure, and the diameter φ ranges from 0 < φ ≤ 0.4 cm.

[0013] Optionally, the negative electrode sheet is a graphite negative electrode sheet, and the current collector of the graphite negative electrode sheet is connected to the negative electrode case.

[0014] Optionally, the button-type three-electrode device for testing electrical properties further includes a positive electrode sheet, a positive electrode case, and a second separator. The negative electrode sheet, the second separator, the positive electrode sheet, and the positive electrode case are arranged in sequence. The positive electrode sheet is connected to the positive electrode case, and the positive electrode case is hermetically connected to the negative electrode case.

[0015] Optionally, the positive electrode sheet is an LFMP positive electrode sheet.

[0016] Optionally, the negative electrode case, the sealant layer, the steel sheet, the reference electrode, the first separator, the negative electrode sheet, the second separator, the LFMP positive electrode sheet, and the positive electrode case are all circular in shape and are coaxially fixed in sequence.

[0017] Optionally, the area of the LFMP positive electrode sheet is 0.785 cm 2 , and the area of the negative electrode sheet is 2.26 cm 2 .

[0018] The beneficial effects of the button-type three-electrode device for testing electrical properties according to the embodiments of the present utility model include, for example:

[0019] The button-type three-electrode device for testing electrical properties includes a negative electrode case, a steel sheet, a sealant layer, a reference electrode, a negative electrode sheet, and a first separator. The negative electrode case is provided with a first hole; the steel sheet is adhesively fixed and isolated from the negative electrode case through the sealant layer, and the steel sheet seals the first hole; the reference electrode and the negative electrode sheet are sequentially fixed on the side of the steel sheet away from the negative electrode case. The reference electrode is connected to the steel sheet, and a first separator is fixed between the negative electrode sheet and the reference electrode. The negative electrode sheet is connected to the negative electrode case.

[0020] While bonding the steel sheet and the negative electrode case, the sealant layer isolates the steel sheet from the negative electrode case, preventing short circuit between the negative electrode case and the steel sheet. The structure is simple and the sealing performance is good. In addition, the steel sheet in this embodiment can be reused. Only one person needs to operate all the equipment after simple training. The slurry mixing, coating, and battery assembly equipment for the button cell are all small desktop devices, which are cheap and easy to operate. Brief Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0022] Figure 1 It is an exploded view of the button-type three-electrode device for testing electrical performance provided in this embodiment;

[0023] Figure 2 It is a schematic diagram of the overall structure of the button-type three-electrode device for testing electrical performance provided in this embodiment.

[0024] Reference numerals: 10 - button-type three-electrode device for testing electrical performance; 100 - negative electrode case; 110 - first hole; 200 - sealant layer; 210 - second hole; 300 - steel sheet; 310 - copper foil; 400 - first separator; 410 - graphite negative electrode sheet; 500 - second separator; 510 - LFMP positive electrode sheet; 600 - positive electrode case. Detailed Description of the Embodiments

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0027] It should be noted that like reference numerals and letters refer to like items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of the present utility model, it should be noted that if terms such as "upper", "lower", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship in which the product of the present utility model is usually placed during use. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0029] In addition, if terms such as "first", "second", etc. are used only for distinguishing descriptions, they cannot be understood as indicating or implying relative importance.

[0030] It should be noted that, without conflict, the features in the embodiments of the present utility model can be combined with each other.

[0031] The following combines Figures 1 to 2 to describe in detail the button-type three-electrode device 10 provided in this embodiment for testing electrical performance.

[0032] Please refer to Figure 1 and Figure 2 , an embodiment of the present utility model provides a button-type three-electrode device 10 for testing electrical performance, including a negative electrode shell 100, a steel sheet 300, a sealing glue layer 200, a reference electrode, a negative electrode sheet, and a first separator 400. The negative electrode shell 100 is provided with a first hole 110; the steel sheet 300 is adhesively fixed and isolated from the negative electrode shell 100 through the sealing glue layer 200, and the steel sheet 300 seals the first hole 110; the reference electrode and the negative electrode sheet are sequentially fixed on the side of the steel sheet 300 away from the negative electrode shell 100. The reference electrode is connected to the steel sheet 300, the first separator 400 is fixed between the negative electrode sheet and the reference electrode, and the negative electrode sheet is connected to the negative electrode shell 100.

[0033] Specifically, the button-type three-electrode battery includes three electrodes, a positive electrode, a negative electrode, and an intermediate electrode. The intermediate electrode is also called a reference electrode or a reference electrode.

[0034] During assembly, the steel sheet 300 is adhesively bonded to the perforated negative electrode shell 100 with sealing glue, the reference electrode is pressed on the steel sheet 300, and at the same time, the reference electrode is separated from the negative electrode sheet by the first separator 400, and the negative electrode sheet is connected to the negative electrode shell 100.

[0035] The negative electrode sheet is connected to the negative electrode case 100, the reference electrode is connected to the steel sheet 300, the sealant layer 200 bonds the steel sheet 300 to the negative electrode case 100 provided with the first hole 110, and at the same time, the steel sheet 300 seals the first hole 110, using the steel sheet 300 as the reference electrode interface for the reference electrode to the outside; while bonding the steel sheet 300 and the negative electrode case 100, the sealant layer 200 isolates the steel sheet 300 from the negative electrode case 100 to prevent short circuit between the negative electrode case 100 and the steel sheet 300. The structure is simple and the sealing performance is good. In addition, the steel sheet 300 in this embodiment can be reused. Only one person needs to operate all the equipment after simple training. The equipment for slurry mixing, coating, and battery assembly of the button battery are all small desktop devices, which are cheap and easy to operate.

[0036] Referring Figure 1 and Figure 2 , in this embodiment, the button-type three-electrode device 10 for testing electrical performance further includes a positive electrode sheet, a positive electrode case 600, and a second separator 500. The negative electrode sheet, the second separator 500, the positive electrode sheet, and the positive electrode case 600 are arranged in sequence. The positive electrode sheet is connected to the positive electrode case 600, and the positive electrode case 600 is hermetically connected to the negative electrode case 100. The positive electrode and the graphite negative electrode are separated by the second separator, and the positive electrode sheet is facing the graphite negative electrode.

[0037] Referring Figure 1 and Figure 2 , in this embodiment, the positive electrode sheet is the LFMP positive electrode sheet 510. The LFMP positive electrode sheet 510, that is, the lithium manganese iron phosphate (LiMn X Fe 1-X PO4, 0 < X < 1, abbreviated as LMFP) positive electrode sheet, is a new type of positive electrode material mainly used for lithium-ion batteries. Using the button-type three-electrode provided in this embodiment to test the electrical performance of lithium manganese iron phosphate has a simple structure and good sealing performance.

[0038] Referring Figure 1 and Figure 2 , in this embodiment, the negative electrode case 100, the sealant layer 200, the steel sheet 300, the reference electrode, the first separator 400, the negative electrode sheet, the second separator 500, the LFMP positive electrode sheet 510, and the positive electrode case 600 are all circular and are coaxially fixed in sequence. The structure is simple and convenient for unified processing and assembly.

[0039] Referring Figure 1 and Figure 2 , in this embodiment, the sealant layer 200 is provided with a second hole 210, and the second hole 210 is coaxially arranged with the first hole 110. In this way, while bonding the steel sheet 300 and the negative electrode case 100, the sealant layer 200 can expose the steel sheet 300 through the second hole 210 in the first hole 110 for connection as the reference electrode to the outside.

[0040] Referring Figure 1And Figure 2 In this embodiment, the aperture of the second hole 210 is smaller than that of the first hole 110. The hole wall of the second hole 210 of the sealant layer 200 is closer to the center relative to the hole wall of the first hole 110. The exposed area of the steel sheet 300 is the area of the second hole 210. There is also the hole wall of the second hole 210 blocking between the steel sheet 300 and the first hole 110, further reducing the possibility of contact between the steel sheet 300 and the first hole 110 and preventing a short circuit between the steel sheet 300 and the negative electrode case 100.

[0041] Refer to Figure 1 And Figure 2 In this embodiment, the sealant layer 200 is in an annular sheet shape. The annular sealant layer 200 is disposed around the first hole 110, achieving fixed connection between the steel sheet 300 and the negative electrode case 100 while achieving a sealed connection.

[0042] Refer to Figure 1 And Figure 2 In this embodiment, the reference electrode is a copper foil 310, and the copper foil 310 is pressed on the side of the steel sheet 300 away from the negative electrode case 100. The copper foil 310 is pressed between the steel sheet 300 and the first separator 400. The copper foil 310 serves as a reference electrode and conducts electricity through the steel sheet 300. The copper foil 310 is a very thin metal foil, usually with a thickness between 0.01 mm and 0.5 mm. It presents a golden-yellow luster and has excellent properties such as high electrical conductivity, high strength, high thermal conductivity, good ductility, plasticity, and corrosion resistance.

[0043] Refer to Figure 1 And Figure 2 In this embodiment, the copper foil 310 has a circular sheet structure, and the diameter φ ranges from 0 < φ ≤ 0.4 cm. Specifically, the reference electrode is a flat small copper foil 310 disc with a diameter of 0 - 0.4 cm, having a uniform stress area and a relatively large area for the supply of chemical reactions, and a relatively high test accuracy.

[0044] Refer to Figure 1 And Figure 2 In this embodiment, the negative electrode sheet is a graphite negative electrode sheet 410, and the current collector of the graphite negative electrode sheet 410 is connected to the negative electrode case 100.

[0045] The graphite negative electrode sheet 410 is a sheet-shaped graphite material processed from natural graphite ore through multiple processes and is mainly used for the negative electrode of lithium-ion batteries. The specific capacity of the graphite negative electrode material is as high as 372 mAh / g, which is one of the highest negative electrode specific capacities in lithium-ion batteries, enabling the lithium-ion battery to have a longer battery life and a higher energy density. The current collector of the graphite negative electrode plays a crucial role in the lithium battery, responsible for collecting the current generated by the active material to form a larger current for external output.

[0046] In this embodiment, the area of the LFMP positive electrode sheet 510 is 0.785 cm 2 , and the area of the negative electrode sheet is 2.26 cm 2 .

[0047] The negative electrode sheet is slightly larger than the LFMP positive electrode sheet 510, the separator is 100 cm 2 , the electrolyte is 0.02 ML, and the stainless steel gasket of the button battery can be reused after the test; only one person can operate all the equipment after simple training. The slurry mixing, coating, and battery assembly equipment of the button battery are all small desktop equipment, which are cheap and easy to operate.

[0048] According to a button-type three-electrode device 10 for testing electrical properties provided by this embodiment, the working principle of the button-type three-electrode device 10 for testing electrical properties includes:

[0049] Use a sealant layer 200 to bond the steel sheet 300 to the negative electrode case 100 with the first hole 110 opened. The sealant layer 200 separates the steel sheet 300 from the negative electrode case 100 while bonding the steel sheet 300 to make a three-electrode interface; when assembling the button battery, press the copper foil 310 as the reference electrode on the steel sheet 300, and at the same time use the first separator 400 to separate the copper foil 310 from the graphite negative electrode sheet 410. Connect the current collector of the graphite negative electrode sheet 410 to the negative electrode case 100, and use the first separator 400 to separate the graphite negative electrode sheet 410 from the copper foil 310 and the steel sheet 300; use the second separator to separate the LFMP positive electrode sheet 510 from the graphite negative electrode, and align the LFMP positive electrode sheet 510 with the graphite negative electrode; Assemble each component into a button-type three-electrode battery in the order of the negative electrode case 100, the sealant layer 200, the steel sheet 300, the copper foil 310, the first separator 400, the negative electrode sheet, the second separator 500, the LFMP positive electrode sheet 510, and the positive electrode case 600.

[0050] A button-type three-electrode device 10 for testing electrical properties provided by this embodiment has at least the following advantages:

[0051] The sealant layer 200 separates the steel sheet 300 from the negative electrode case 100 while bonding the steel sheet 300 to the negative electrode case 100, preventing a short circuit between the negative electrode case 100 and the steel sheet 300. The structure is simple and the sealing performance is good. In addition, the steel sheet 300 in this embodiment can be reused, and only one person can operate all the equipment after simple training.

[0052] Button-type battery three-electrode test: low material cost, low utilization rate of materials and components, small amounts of electrode sheets, separators, and electrolytes used, and the steel sheet 300 in the battery can be reused; one person can complete the operation, the sample preparation process is simple, the equipment is simple, and the success rate is high; the operation difficulty is low and the requirements for the test equipment are low.

[0053] The above are only specific embodiments of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the protection scope of the claims described above.

Claims

1. A button-type three-electrode device for testing electrical properties, characterized in that: include: A negative electrode shell (100), wherein the negative electrode shell (100) is provided with a first hole (110); A steel sheet (300) and a sealing adhesive layer (200), wherein the steel sheet (300) and the negative electrode shell (100) are bonded, fixed and isolated by the sealing adhesive layer (200), and the steel sheet (300) seals the first hole (110); A reference electrode, a negative electrode sheet and a first diaphragm (400), wherein the reference electrode and the negative electrode sheet are fixed in sequence on a side of the steel sheet (300) away from the negative electrode shell (100), the reference electrode is connected to the steel sheet (300), the first diaphragm (400) is fixed between the negative electrode sheet and the reference electrode, and the negative electrode sheet is connected to the negative electrode shell (100).

2. The button-type three-electrode device for testing electrical properties according to claim 1, characterized in that: The sealant layer (200) is provided with a second hole (210), and the second hole (210) is coaxially arranged with the first hole (110).

3. The button-type three-electrode device for testing electrical properties according to claim 2, characterized in that: The diameter of the second hole (210) is smaller than the diameter of the first hole (110).

4. The button-type three-electrode device for testing electrical properties according to claim 1, characterized in that: The reference electrode is a copper foil (310), and the copper foil (310) is pressed on a side of the steel sheet (300) away from the negative electrode shell (100).

5. The button-type three-electrode device for testing electrical properties according to claim 4, characterized in that: The copper foil (310) is a disc structure, and the diameter φ ranges from 0<φ≤0.4cm.

6. The button-type three-electrode device for testing electrical properties according to claim 1, characterized in that: The negative electrode sheet is a graphite negative electrode sheet (410), and the current collector of the graphite negative electrode sheet (410) is connected to the negative electrode shell (100).

7. The button-type three-electrode device for testing electrical properties according to any one of claims 1 to 6, characterized in that: The button-type three-electrode device for testing electrical performance further comprises a positive electrode sheet, a positive electrode shell (600) and a second diaphragm (500); the negative electrode sheet, the second diaphragm (500), the positive electrode sheet and the positive electrode shell (600) are arranged in sequence; the positive electrode sheet is connected to the positive electrode shell (600); and the positive electrode shell (600) is sealed and connected to the negative electrode shell (100).

8. The button-type three-electrode device for testing electrical properties according to claim 7, characterized in that: The positive electrode sheet is a LFMP positive electrode sheet (510).

9. The button-type three-electrode device for testing electrical properties according to claim 8, characterized in that: The negative electrode shell (100), the sealant layer (200), the steel sheet (300), the reference electrode, the first diaphragm (400), the negative electrode sheet, the second diaphragm (500), the LFMP positive electrode sheet (510) and the positive electrode shell (600) are all circular in shape and are coaxially fixed in sequence.

10. The button-type three-electrode device for testing electrical properties according to claim 8, characterized in that: The area of ​​the LFMP positive electrode sheet (510) is 0.785 cm 2 The area of ​​the negative electrode sheet is 2.26 cm 2 .

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