Sample preparation device for testing bonding strength of pole piece

Abstract

The utility model discloses a sample preparation device for testing the bonding strength of a pole piece. The sample preparation device comprises an adhesive tape bonding unit and a rolling unit, wherein the adhesive tape bonding unit is used for bonding an adhesive tape on the surface of a preset metal plate to form a pole piece bonding body; and the rolling unit is used for carrying out rolling forming on the pole piece bonding body and the bonded pole piece. According to the pole piece bonding strength test sample preparation device disclosed by the utility model, the adhesive tape bonding unit can be used for conveniently bonding the adhesive tape on the surface of the preset metal plate to form a pole piece bonding body, and the rolling unit can be used for quickly and effectively carrying out rolling forming on the pole piece bonding body and a pole piece bonded on the pole piece bonding body; therefore, rapid sample preparation is realized, and the prepared sample is ensured to meet requirements and test requirements.

Description

Technical Field

[0001] The utility model relates to the technical field of pole piece test sample preparation, in particular to a device for preparing a sample for testing the bonding strength of a pole piece. Background Technique

[0002] The general process of the manufacturing process of lithium-ion batteries is as follows: materials such as active substances, binders, conductive agents, and solvents are mixed by a planetary stirrer or a centrifugal mixer to prepare a slurry, and then the slurry is coated on both sides of a copper or aluminum current collector, and a pole piece is obtained after drying in an oven. During the electrode manufacturing process, the binder plays an extremely important role in the lithium battery and is one of the important materials that must be used. Its main function is to bond the electrode active substance and the conductive agent to the electrode current collector, so that there is good overall connectivity between the powder materials, and there is a certain bonding strength between the powder materials and the pole piece. The bonding strength refers to the connection strength between the pole piece and the current collector. Good bonding strength means that the contact between the pole piece and the current collector is tight, which can more effectively transmit current and improve the performance and life of the battery. On the contrary, low bonding strength between the coating and the current collector will increase the contact resistance, thereby increasing the total internal resistance of the battery, making it difficult to transmit current, unable to meet the requirements of high-rate operation, and even possibly causing thermal runaway or safety problems; there may also be a situation where the coating peels off during the cycle of the battery due to insufficient bonding strength of the pole piece, ultimately resulting in a decline in the cycle capacity.

[0003] The test of the bonding strength of the pole piece can be used to evaluate whether the use of the binder is reasonable and whether the produced pole piece meets the requirements of actual production. The test usually uses the 180° peel test method to conduct a peel force test. That is, a transparent tape and a double-sided tape are successively fixed on a metal plate, and then the cut pole piece is pasted on the double-sided tape. Finally, the metal plate with the pole piece sample is placed upright on a tensile machine, and the pole piece sample is pulled by the tensile machine. The powder on the pole piece sample adheres to the double-sided tape and thus detaches from the current collector. This test sample preparation technology generally adopts manual sample preparation. The sample preparation process requires cutting multiple tapes and pole pieces with a fixed area, which is cumbersome and takes a long time to prepare.

[0004] At present, the testing of the bonding strength of the electrode sheet mostly focuses on the construction of testing fixtures and equipment for the bonding force of the battery electrode sheet, and rarely improves the sample preparation process for testing the bonding strength of the electrode sheet. In the prior art, the method for improving the sample preparation process is mainly to transport through a conveyor belt and tightly bond the metal plate, tape, and electrode sheet through a rolling roller. For example, the patent with publication number CN116625774A discloses a sample preparation device and method for testing the bonding force of an electrode binder. The sample preparation device for testing the bonding force of an electrode binder includes a rolling module formed by at least three rolling roller groups. The rolling roller groups are arranged at intervals in the radial direction. Each rolling roller group includes an upper rolling roller and a lower rolling roller. On the outer side of the first lower rolling roller of a rolling roller group on the feeding side of the rolling module, a feeding roller is arranged. The feeding roller is connected to the first lower rolling roller through a conveyor belt to form a conveyor belt. The present invention can realize sample preparation in the way of layer-by-layer pasting and rolling, reduce the bubbles and wrinkles between the sample preparation metal plate and the protective tape, between the protective tape and the double-sided tape, and between the double-sided tape and the electrode sheet to be tested, reduce the probability that the peeling process occurs between the double-sided tape and the electrode due to external mechanical factors, and ensure the flatness of the sample made by the bonding force testing sample preparation device. This device does not optimize the gluing process; and does not fix the position of the metal plate, and the deviation of the metal plate position during transportation may lead to abnormal testing of the electrode sheet bonding force.

[0005] Based on this, it is extremely important to design a convenient, fast, and stable sample preparation device for the bonding force of the electrode sheet. Utility Model Content

[0006] The purpose of the present utility model is to overcome the deficiencies and defects of the prior art, and provide a sample preparation device for testing the bonding strength of the electrode sheet that is convenient to use, fast, and stable.

[0007] A sample preparation device for testing the bonding strength of the electrode sheet includes a tape bonding unit for bonding a tape to the surface of a preset metal plate to form an electrode sheet bonding body, and a rolling unit for rolling and forming the electrode sheet bonding body and the bonded electrode sheet.

[0008] Among them, the tape bonding unit includes a housing and a first tape wheel and a second tape wheel placed in the housing. A double-sided tape and a transparent tape are respectively wound on the first tape wheel and the second tape wheel; after bonding the tape to the metal plate, the transparent tape is bonded between the metal plate and the double-sided tape.

[0009] Among them, the housing has a tape outlet, and there is an adhesive head outside the tape outlet. The adhesive head is detachably connected to a fixed plate arranged in the housing.

[0010] Among them, the metal plate is a rectangular plate, and clamping edges for clamping and matching with the rolling unit are provided on opposite sides of the metal plate.

[0011] Among them, the rolling unit includes a positioning frame, a rolling shaft located inside the positioning frame and capable of moving along the length direction of the positioning frame, and sliding columns at both ends of the rolling shaft are in sliding fit with sliding grooves on opposite sides of the inner wall of the positioning frame; a pull rod vertically connected to the cylindrical surface of the sliding column passes through a linear hole in the bottom surface of the positioning frame and is connected to a fixing plate below the positioning frame by an elastic rope.

[0012] Among them, a clamping groove for cooperating with the clamping edge of the metal plate is provided below the sliding groove.

[0013] Among them, both ends of the fixing plate are clamped and connected to two clamping plates, the two clamping plates are oppositely arranged on the bottom plate, the positioning frame is fixed on a support plate, and the support plate is arranged above the bottom plate through support columns.

[0014] Among them, a plurality of clamping grooves are provided on the relative inner side surfaces of the clamping plates, and the plurality of clamping grooves are arranged along the height direction of the clamping plates.

[0015] Among them, the cylindrical surface of the rolling shaft is fixedly connected to a U-shaped handle.

[0016] Among them, a rope hole is formed on the upper surface of the fixing plate, and both ends of the elastic rope are respectively connected to the two pull rods and pass through the rope hole to realize connection with the fixing plate.

[0017] For the sample preparation device for testing the bonding strength of the pole piece of the present utility model, its tape bonding unit can conveniently bond the tape on the surface of a preset metal plate to form a pole piece bonding body, and the rolling unit can quickly and effectively roll and form the pole piece bonding body and the bonded pole piece thereon, so as to realize rapid sample preparation and ensure that the prepared sample meets the requirements and satisfies the test needs. Description of the Drawings

[0018] Figure 1 is a schematic diagram of the tape bonding unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0019] Figure 2 is a schematic diagram of the first housing and its internal structure of the tape bonding unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0020] Figure 3 is a schematic diagram of the second housing of the tape bonding unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0021] Figure 4 is a schematic diagram of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0022] Figure 5It is a schematic diagram of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model, excluding the rolling shaft and its components.

[0023] Figure 6 It is a schematic diagram of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model, excluding the rolling shaft and its components, and the pole piece to be rolled.

[0024] Figure 7 It is an axonometric schematic diagram of the support structure of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0025] Figure 8 It is a top view schematic diagram of the support structure of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0026] Figure 9 It is an axonometric schematic diagram of the positioning frame of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0027] Figure 10 It is a top view schematic diagram of the positioning frame of the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0028] Figure 11 It is a schematic diagram of the pole piece bonding body to be processed by the rolling unit of the sample preparation device for testing the bonding strength of the pole piece of the present utility model bonded to the pole piece.

[0029] Figure 12 It is a schematic diagram of the connection structure of the rolling shaft of the sample preparation device for testing the bonding strength of the pole piece of the present utility model.

[0030] Figure 13 It is a partial schematic diagram of the connection structure of the rolling shaft of the sample preparation device for testing the bonding strength of the pole piece of the present utility model. Detailed implementation manners

[0031] The following further elaborates on the present utility model in detail in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0032] In the sample preparation device for testing the bonding strength of the pole piece of the present utility model, it includes a tape bonding unit 100 that can be disassembled and cleaned and a rolling unit 200. The tape bonding unit 100 can bond a double-sided tape 105, a transparent tape 106 and a metal plate 300 (such as a plate made of steel plate or similar material) for making a sample in advance to form a pole piece bonding body; the metal plate 300 can be fixed inside the rolling unit 200 and the rolling pressure is adjustable.

[0033] Please refer to the attached Figures 1 to 13As shown, the sample preparation device for testing the bonding strength of the electrode tab includes a tape bonding unit 100 for bonding a tape 302 to the surface of a preset metal plate 300 to form an electrode tab bonding body, and a rolling unit 200 for rolling and forming the electrode tab bonding body and the bonded electrode tab.

[0034] In one embodiment, the tape bonding unit 100 includes a housing and a first tape wheel 103 and a second tape wheel 104 disposed in the housing. A double-sided tape 105 and a transparent tape 106 are respectively wound around the first tape wheel and the second tape wheel. In this application, the tape 302 for bonding with the electrode tab 400 on the electrode tab bonding body includes a double-sided tape 105 and a transparent tape 106. After bonding the tape 302 to the metal plate 300, the transparent tape is bonded between the metal plate and the double-sided tape.

[0035] Specifically, the housing includes a first housing 113 and a second housing 108. The inner surface of the first housing is provided with the first tape wheel 103 and the second tape wheel 104. The first housing is snap-connected to the corresponding fixing holes 109 on the second housing through two fixing columns 112 at the centers of the first tape wheel and the second tape wheel, and is engaged with the strip portion 110 on the second housing 108 through the card slots 107 on the two connecting surfaces of the first housing 113.

[0036] Among them, the housing has a tape outlet 111, and there is an adhesive head 101 outside the tape outlet. The adhesive head is detachably connected to a fixing plate 102 disposed in the housing. The fixing plate 102 can be fixed in the first housing and can be integrally injection-molded with the first housing 113. The main body of the adhesive head 101 is triangular in shape, and a connecting portion is provided at the rear end to facilitate connection with the fixing plate, such as by means of plug connection, such as by means of the cooperation of mortise and tenon.

[0037] During bonding, place the metal plate flat on the table, and stick the adhesive surface of the transparent tape to one end of the metal plate; then paste the double-sided tape (with the adhesive surface on the inner side) and the transparent tape (with the adhesive surface on the inner side) to the surface of the metal plate through the adhesive head. After bonding, cut the tape with a blade. Through the tape bonding unit, the double-sided tape and the transparent tape can be sequentially bonded to the surface of the metal plate without manual operation by the operator, and the bonding process is already completed inside the tape bonding unit, which can ensure a relatively high bonding alignment degree.

[0038] In a preferred embodiment, the metal plate 300 is a rectangular plate, and the opposite sides of the metal plate 300 have clamping edges 301 for clamping and matching with the rolling unit. See Figure 11As shown, by providing the clamping edge 301, after the metal plate is fixedly connected to the rolling unit, it is convenient to prevent the displacement of the metal plate and the pole piece thereon, which may affect the rolling, so as to facilitate the rolling forming of the pole piece adhered thereto to form a test specimen.

[0039] In one embodiment, referring to Figure 4 As shown, the rolling unit 200 includes a positioning frame 201 and a rolling shaft 206 located within the positioning frame and capable of moving along the length direction of the positioning frame. Referring to Figure 12 As shown, the sliding columns 207 at both ends of the rolling shaft 206 are slidably engaged with the sliding grooves 2011 on the opposite sides of the inner wall of the positioning frame 201 (refer to Figure 9 As shown); the pull rod 208 perpendicularly connected to the cylindrical surface of the sliding column 207 passes through the linear hole 2015 at the bottom surface of the positioning frame (refer to Figure 10 As shown), and is connected to the fixing plate 210 below the positioning frame by an elastic rope 209.

[0040] In one embodiment, an elastic layer (not shown) is arranged in the sliding groove 2011, and the sliding column is arranged in the sliding groove through the elastic layer. The elastic layer can be realized by arranging an elastic material in the groove of the sliding groove, such as arranging a rubber layer. In this way, a certain displacement of the rolling shaft in the vertical direction can be realized to facilitate the control of the rolling pressure on the pole piece. In the above technical solution, the elastic rope 209 can be realized by a rubber rope. During rolling, the elastic rope provides a downward pulling force, which can enable the rolling shaft to obtain a downward pulling force, pull the handle to move the rolling shaft on the surface of the pole piece, and achieve the purpose of rolling the pole piece, so as to ensure a certain pressure of the rolling shaft on the metal plate for rolling the bonded test pole piece, that is, to ensure the consistency of the sample preparation process for testing the bonding force of different pole pieces.

[0041] In one embodiment, a clamping groove 2012 for cooperating with the clamping edge 301 of the metal plate 300 is provided below the sliding groove 2011. The clamping groove is arranged parallel to the sliding groove. After the clamping edges on both sides of the metal plate are clamped in the clamping groove, the metal plate and the pole piece thereon can be fixed in the positioning frame to prevent displacement during the rolling process and affect the rolling effect.

[0042] In one embodiment, both ends of the fixing plate 210 are clamped to two clamping plates 205 to form a detachable connection. The two clamping plates 205 are oppositely arranged on the bottom plate 203. The positioning frame 201 is fixed to a support plate 202, and the support plate 202 is arranged above the bottom plate 203 through support columns 204. Preferably, there are three support columns 204, which are arranged at intervals in a triangular shape to support the positioning frame above the bottom plate. The positioning frame 201 can be formed by connecting a bottom plate 2013 and a U-shaped plate 2014 on the bottom plate as shown in the figure (see Figure 9 shown), or other forms of structures can also be adopted, and it is not limited to this.

[0043] In one embodiment, the relatively inner surfaces of the clamping plates 205 have a plurality of clamping grooves 2051. The plurality of clamping grooves 2051 are arranged along the height direction of the clamping plates 205. The cross-sectional shape of the clamping grooves matches the shapes of both ends of the fixing plate 210, so that the insertion and convenient disassembly of the two can be realized. For example, a triangular groove structure and triangular end heads are adopted. Through the clamping grooves, different-height clamping grooves can be selected to connect with the fixing plate according to the thickness of different pole pieces during use, so that the pressure for rolling the pole pieces can be adjusted according to the thickness of the pole pieces.

[0044] In one embodiment, the cylindrical surface of the rolling shaft 206 is connected and fixed to the U-shaped handle 211. By providing the U-shaped handle 211, it is convenient for the operator to operate, such as pulling the rolling shaft 206 to move or pressing the rolling shaft 206, etc., to carry out the sample preparation of the pole pieces.

[0045] In one embodiment, a rope hole is formed on the upper surface of the fixing plate 210. Both ends of the elastic rope are respectively connected to the two pull rods and pass through the rope hole to realize the connection with the fixing plate. Specifically, both ends of the elastic rope 209 are respectively fixed to the middle part of the bottom of the pull rod with hollow in the middle through the screw combination with the threaded parts 212 on both sides of the pull rod 208. The rope hole is realized by welding a ring body or a U-shaped body 2101 (the U-shaped body forms a hole with the surface of the fixing plate) on one side surface of the fixing plate.

[0046] For the pole piece bonding strength test sample preparation device of the present invention, its tape bonding unit can bond the double-sided tape and the transparent tape to the prefabricated metal plate in advance, which not only saves time, but also can reduce the generation of bubbles during the bonding process; its rolling unit can fix the metal plate 300 of the bonding test pole piece 400 (bonded to the surface of the tape 302) inside it to prevent the metal plate from moving during the rolling process, resulting in uneven rolling pressure on the surface of the pole piece; by fixing the tension of the elastic rope, the consistency of the sample preparation process for testing the bonding force of different pole pieces can be ensured; due to the inconsistent thickness of different pole pieces, by selecting the clamping grooves with different heights on the clamping plate to connect with the fixing plate, the best rolling pressure for the pole pieces can be obtained.

[0047] The sample preparation device for testing the bonding strength of the pole piece of the present utility model can be disassembled and cleaned, which can avoid the influence of the residual pole powder inside the device on the test caused by too long use time.

[0048] The above shows and describes the basic principles, main features and advantages of the present utility model. For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic features of the present utility model, the present utility model can be implemented in other specific forms.

[0049] Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present utility model.

[0050] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. Sample preparation device for testing the bonding strength of a pole piece, characterized in that, It includes a tape bonding unit for bonding a tape to the surface of a preset metal plate to form a pole piece bonding body, and a rolling unit for rolling and forming the pole piece bonding body and the bonded pole piece; the tape bonding unit includes a housing and a first tape wheel and a second tape wheel disposed inside the housing, with a double-sided tape and a transparent tape wound around the first tape wheel and the second tape wheel respectively; after the tape is bonded to the metal plate, the transparent tape is bonded between the metal plate and the double-sided tape; the rolling unit includes a positioning frame, a rolling shaft that can move along the length direction of the positioning frame and is located inside the positioning frame, and sliding columns at both ends of the rolling shaft are slidably engaged with sliding grooves on opposite sides of the inner wall of the positioning frame; after a pull rod perpendicularly connected to the cylindrical surface of the sliding column passes through a linear hole at the bottom surface of the positioning frame, it is connected to a fixing plate below the positioning frame by an elastic rope.

2. The sample preparation device for testing the bonding strength of the electrode sheet according to claim 1, characterized in that, The housing includes a first housing and a second housing. The inner surface of the first housing is provided with the first tape wheel and the second tape wheel. The first housing is snap-connected to corresponding fixing holes on the second housing through two fixing columns at the centers of the first tape wheel and the second tape wheel, and is engaged with a strip portion on the second housing through clamping grooves on two connection surfaces of the first housing.

3. The sample preparation device for testing the bonding strength of the pole piece according to claim 2, wherein The housing has a tape outlet, and there is an adhesive head outside the tape outlet. The adhesive head is detachably connected to a fixing plate disposed inside the housing.

4. The sample preparation device for testing the bonding strength of the pole piece according to claim 1, wherein, The metal plate is a rectangular plate, and opposite sides of the metal plate have clamping edges for clamping and mating with the rolling unit.

5. The sample preparation device for testing the bonding strength of the pole piece according to claim 1, characterized in that, An elastic layer is disposed in the sliding groove, and the sliding column is disposed in the sliding groove through the elastic layer.

6. The sample preparation device for testing the bonding strength of the pole piece according to claim 1, wherein, Below the sliding groove, there is a clamping groove for mating with the clamping edge of the metal plate.

7. The sample preparation device for testing the bonding strength of the pole piece according to claim 1, characterized in that, Both ends of the fixing plate are snap-connected to two clamping plates. The two clamping plates are oppositely disposed on a bottom plate. The positioning frame is fixed to a support plate, and the support plate is disposed above the bottom plate through support columns.

8. The sample preparation device for testing the bonding strength of the electrode sheet according to claim 7, wherein, The opposite inner surfaces of the clamping plates have a plurality of clamping grooves, and the plurality of clamping grooves are arranged along the height direction of the clamping plates.

9. The sample preparation device for testing the bonding strength of the pole piece according to claim 1, wherein, The cylindrical surface of the rolling shaft is fixedly connected to a U-shaped handle.

10. The sample preparation device for testing the bonding strength of the electrode sheet according to claim 1, wherein, A rope hole is formed on the upper surface of the fixing plate. Both ends of the elastic rope are respectively connected to the two pull rods and are connected to the fixing plate by passing through the rope hole.

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