Manufacturing method and manufacturing device of tab type pole piece, electrode pole piece and battery

Abstract

The invention belongs to the technical field of batteries, and provides a manufacturing method and a manufacturing device of a tab type pole piece, an electrode pole piece and a battery, the manufacturing method comprises the following steps: forming a functional separation layer on any one of a cleaning point position, a cleaning area or a coating area on a current collector; the functional separation layer comprises a conductive agent type material and an adhesive type material with the mass percentage of 38%-67%; forming an active layer on the coating area, and covering the existing functional separation layer; and performing laser cleaning on the cleaning point position or the cleaning area, removing the functional separation layer and the active layer covering the functional separation layer, forming a tab slot position, and arranging a tab to obtain the electrode plate. According to the manufacturing method, bonding between the active layer and the current collector can be efficiently stripped during laser cleaning, active substance residues of different degrees on the surface of the current collector are reduced, and the effectiveness and reliability of tab welding are effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of battery manufacturing technology, and relates to a method and apparatus for manufacturing tab-type electrode sheets, electrode sheets and batteries. Background Technology

[0002] Lithium-ion batteries, due to their high energy density, long cycle life, and excellent power characteristics, are widely used in smartphones, laptops, tablets, Bluetooth headsets, power tools, electric vehicles, and energy storage systems. As users' demands for a better user experience increase, shortening charging time has become a key direction for battery technology development. To improve the fast-charging performance of battery cells, a centrally located tab structure is commonly adopted. This structure creates a low-resistance current collection path by reserving a blank foil area in the center of the electrode (i.e., the tab groove), thereby reducing local polarization and improving rate performance. The formation of this groove requires thorough removal of the active material coating to ensure a clean current collector surface, guaranteeing the reliability of subsequent tab welding and the stability of the electrical connection.

[0003] Currently, laser cleaning technology is mainly used in industry to prepare positive electrode tab slots. This method uses a high-energy laser beam to perform multiple high-speed scans on the target area, causing the coating to vibrate, spatter, ablate, melt, decompose, and even vaporize through photothermal and photomechanical effects, thereby peeling off the active material layer. However, the current mainstream positive electrode material system is trending towards smaller particles to improve rate performance. The reduction in particle size leads to a significant increase in specific surface area. To maintain the mechanical integrity of the electrode, a higher proportion of binder needs to be added to enhance the interfacial bonding strength between the active material and the aluminum current collector. In this context, the process window of existing laser cleaning equipment is extremely narrow: if the energy density is too low, it is difficult to effectively destroy the strong bonding interface, resulting in a large amount of active material remaining on the current collector surface; if the energy is too high, it is easy to cause aluminum foil to melt through, oxidize, or drastically increase surface roughness, affecting the welding quality. Moreover, in actual production, the positive electrode slots often have varying degrees of coating residue, which not only reduces the consistency of laser welding penetration but may also cause incomplete welding, increased contact resistance, or even the risk of thermal runaway. Furthermore, different cathode systems exhibit varying sensitivities to laser parameters due to differences in composition, particle size, and binder content, making it difficult to establish a universal cleaning process and further limiting the adaptability and yield stability of this technology.

[0004] Therefore, the existing laser cleaning-based methods for manufacturing center-mounted tabs are insufficient, and there is an urgent need to develop a new manufacturing method that can efficiently, reliably, and universally achieve tab slot cleaning, especially suitable for manufacturing center-mounted tab type electrodes. Summary of the Invention

[0005] In view of the problems existing in the prior art, the purpose of this invention is to provide a method and apparatus for manufacturing tab-type electrode sheets, electrode sheets, and batteries. The manufacturing method involves forming a specific functional separation layer on any one of the cleaning points, cleaning areas, or coating areas on a current collector. The functional separation layer includes a specific proportion of conductive agent and adhesive material. Then, an active layer is formed on the coating area to cover the existing functional separation layer. Laser cleaning is then performed on the cleaning points or cleaning areas to remove the functional separation layer and the active layer covering it, forming tab grooves. The electrode sheet is obtained by setting the tabs. This manufacturing method can efficiently peel off the adhesion between the active layer and the current collector during laser cleaning, reducing the degree of active material residue on the current collector surface and effectively improving the effectiveness and reliability of tab welding.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for manufacturing a tab-type electrode, comprising the following steps:

[0008] A current collector is provided, wherein the surface of the current collector to be coated has a coating area, the coating area includes a cleaning area, and the cleaning area includes cleaning points;

[0009] A functional separation layer is formed on any one of the cleaning points, cleaning areas, or coating areas; the functional separation layer comprises conductive agent materials and adhesive materials, and the mass of the conductive agent materials accounts for 38% to 67% of the mass of the functional separation layer;

[0010] An active layer is formed on the coating area, covering the existing functional separation layer;

[0011] Laser cleaning is performed on the cleaning points or the cleaning area to remove the functional separation layer and the active layer covering it, forming tab grooves;

[0012] A tab is provided in the tab slot to obtain an electrode plate.

[0013] The manufacturing method described in this invention can efficiently peel off the adhesion between the active layer and the current collector during laser cleaning. The functional separation layer is easy to clean, which can reduce the residual active material on the surface of the current collector to varying degrees. It also has no adverse effects on the thickness of the electrode sheet, the interfacial bonding, etc., and can effectively improve the effectiveness and reliability of the middle electrode tab welding.

[0014] This invention does not limit the specific shape and style of the functional separation layer. It can be set in various positions according to the location, quantity, shape and arrangement characteristics of the setting area. For example, when set on the coating area, it can present a large-area rectangular coating pattern according to the shape of the coating area; when set on the cleaning area, it can present a strip coating pattern according to the shape of the cleaning area; when set on the cleaning points, it can present a dotted coating or an array coating pattern according to the shape and arrangement characteristics of the cleaning points.

[0015] The conductive agent material of the present invention accounts for 38% to 67% of the mass of the functional separation layer, for example, it can be 38%, 40%, 43%, 45%, 48%, 50%, 53%, 55%, 58%, 60%, 63%, 65% or 67%, etc.

[0016] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The technical objectives and beneficial effects of the present invention can be better achieved and realized through the following technical solutions.

[0017] As a preferred embodiment of the present invention, the resistance of the current collector is less than 2mΩ, for example, it can be 1.9mΩ, 1.8mΩ, 1.5mΩ, 1.2mΩ, 1mΩ, 0.8mΩ, 0.5mΩ or 0.1mΩ, etc.

[0018] As a preferred embodiment of the present invention, the electrode tab includes a centrally located electrode tab.

[0019] It should also be noted that the coating area includes both the cleaning area and the non-cleaning area; the cleaning area includes both cleaning points and non-cleaning points. When the functional separation layer of the present invention is coated over a large area in the coating area, the functional separation layer and the active layer on it covering the cleaning area or cleaning point in the coating area are removed during laser cleaning, but the functional separation layer is still retained in the non-cleaning area or non-cleaning point, that is, the functional separation layer is still retained in the electrode sheet. This functional separation layer not only helps to reduce the impact of the functional separation layer as a base coating on the internal resistance of the cell, but also helps to improve the bonding between the active layer and the current collector, and improve the peeling force, with an improvement effect of >20%.

[0020] As a preferred embodiment of the present invention, the adhesive material accounts for 28% to 62% of the mass of the functional separation layer. Exemplarily, it can be 28%, 30%, 33%, 35%, 38%, 40%, 43%, 45%, 48%, 50%, 53%, 55%, 58%, 60%, or 62%, etc.

[0021] The functional separation layer in this invention has a high content of adhesive materials, which is beneficial to achieve a compression of nearly 50% after rolling. When applying a thin coating to a large area, the impact on the thickness of the electrode sheet and the cell is significantly reduced. The overall thickness difference of the cell in batch sample data can be less than or equal to 0.22%. Therefore, it can have the advantages of traditional primer coating while also optimizing the effect of laser cleaning.

[0022] As a preferred technical solution of the present invention, the mass ratio of the conductive agent material to the adhesive material is 1:(0.5~1.5), for example, it can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4 or 1:1.5, etc.

[0023] As a preferred embodiment of the present invention, the thickness of the functional separation layer is 0.5% to 50% of the thickness of the active layer. For example, it can be 0.5%, 1%, 3%, 5%, 8%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50%, etc.

[0024] As a preferred embodiment of the present invention, the thickness of the functional separation layer is 0.5 μm to 2 μm. Exemplarily, it can be 0.5 μm, 0.8 μm, 1 μm, 1.3 μm, 1.5 μm, 1.8 μm, or 2 μm, etc.

[0025] As a preferred embodiment of the present invention, the functional separation layer further includes an auxiliary agent, which includes at least one of magnesium hydroxide, calcium hydroxide, or aluminum hydroxide.

[0026] As a preferred embodiment of the present invention, the mass of the additive accounts for 0% to 5% of the total mass of the conductive agent and the adhesive. For example, it can be 0% (excluding additive), 0.01%, 0.05%, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, etc.

[0027] The functional separation layer of the present invention may also optionally include an auxiliary agent. The flexible use of the auxiliary agent can effectively adjust the pH value of the current collector of the functional separation layer and avoid corrosion of the current collector.

[0028] As a preferred technical solution of the present invention, the electrode sheet includes a positive electrode sheet or a negative electrode sheet; that is, the current collector includes a positive current collector or a negative current collector, and the active layer correspondingly includes a positive active layer or a negative active layer.

[0029] As a preferred technical solution of the present invention, the positive electrode sheet includes a positive electrode active material, which includes at least one of ternary materials (NCM), lithium iron phosphate (LFP), lithium manganese oxide (LMO), lithium manganese iron phosphate (LMFP), or lithium cobalt oxide (LCO).

[0030] As a preferred technical solution of the present invention, the conductive agent material includes at least one of acetylene black, Ketjen black, conductive carbon black (SP), or carbon nanotubes (CNT).

[0031] As a preferred embodiment of the present invention, the adhesive material includes at least one of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), polyimide (PI), or polyvinylidene fluoride (PVDF).

[0032] As a preferred embodiment of the present invention, the laser cleaning includes a first laser cleaning, a second laser cleaning, a third laser cleaning, and a fourth laser cleaning; the first laser cleaning is used to clean the active layer covering the surface of the functional separation layer; the second laser cleaning is used to clean the transition interface between the functional separation layer and the active layer; the third laser cleaning is used to clean the functional separation layer; and the fourth laser cleaning is used to clean the residue on the surface of the current collector.

[0033] As a preferred embodiment of the present invention, the power of the first laser cleaning is 800W~1600W, for example, 800W, 900W, 1000W, 1100W, 1200W, 1300W, 1400W, 1500W or 1600W; the power of the second laser cleaning is 500W~1000W, for example, 500W, 600W, 700W, 800W, 900W or 1000W; the power of the third laser cleaning is 100W~500W, for example, 100W, 200W, 300W, 400W or 500W; and the power of the fourth laser cleaning is 100W~300W, for example, 100W, 150W, 200W, 250W or 300W.

[0034] In this invention, the functional separation coating of conductive and adhesive materials is relatively thin, which can be cleaned with a lower power laser. This can improve the heat absorption uniformity during laser cleaning, thereby effectively reducing surface damage to local current collectors and improving the sample preparation efficiency of laser cleaning.

[0035] In a second aspect, the present invention provides an electrode sheet, which is obtained according to the manufacturing method described in the first aspect.

[0036] Thirdly, the present invention provides a battery comprising the battery electrodes described in the second aspect.

[0037] Fourthly, the present invention provides an apparatus for manufacturing tab-type electrodes, the apparatus being used to operate the manufacturing method described in the first aspect, along the moving and conveying direction of the current collector, the apparatus comprising a sensor, a functional separation layer coating device, and a winding mechanism arranged sequentially, the sensor being used to detect the position of the functional separation layer and control the functional separation layer coating device to coat and form the functional separation layer at the corresponding position, the winding mechanism being used to wind up the current collector having formed the functional separation layer.

[0038] It should be noted that, due to space limitations and to avoid redundancy, this invention does not exhaustively list all point values ​​within the above numerical range, but it is not limited to the listed values ​​either; other unlisted values ​​within the above numerical range are also applicable.

[0039] Compared with existing technical solutions, the present invention has at least the following beneficial effects:

[0040] The functional separation layer in the manufacturing method of this invention can be flexibly configured. It can be applied to a large area corresponding to the active material coating area, or to a horizontal streak coating corresponding to the cleaning area, or to a precise spot coating corresponding to the cleaning points. Regardless of the method, after laser cleaning at the location requiring cleaning, the active material and the foil (current collector) are completely separated, resulting in high cleanliness and simpler processing. It can efficiently peel off the adhesion between the active layer and the current collector during laser cleaning, reducing the residual active material on the current collector surface to varying degrees, and has no adverse effects on the thickness of the electrode sheet, interface bonding, etc., which can effectively improve the effectiveness and reliability of the middle electrode tab welding.

[0041] The functional separation layer of this invention mainly comprises high content of conductive agent materials and adhesive materials, which helps to reduce the impact of the functional separation layer on the internal resistance of the battery cell when used as a base layer. It also helps to improve the bonding between the active layer and the current collector and improve the peeling force. Moreover, the functional separation coating is relatively thin and can be cleaned with a lower power laser, which can improve the heat absorption uniformity during laser cleaning, thereby effectively reducing local surface damage to the current collector and improving the sample preparation efficiency of laser cleaning.

[0042] The functional separation layer of the present invention may also optionally include an additive. The flexible use of the additive can effectively adjust the pH value of the current collector of the functional separation layer and avoid it from corroding the foil (current collector). Attached Figure Description

[0043] Figure 1 This is a cross-sectional schematic diagram of the electrode sheet before laser cleaning in Example 1.

[0044] Figure 2 This is a cross-sectional schematic diagram of the electrode sheet after the second laser cleaning in Example 1.

[0045] Figure 3 This is a cross-sectional schematic diagram of the electrode sheet after the fourth laser cleaning in Example 1.

[0046] Figure 4 This is a schematic diagram of the manufacturing apparatus for the tab-type electrode sheet in Example 1.

[0047] Figure 5 This is a schematic diagram of Example 1 showing the setting of a functional separation layer in the cleaning area.

[0048] Figure 6 This is a schematic diagram of Example 2 showing the setting of a functional separation layer in the coating area.

[0049] Figure 7 This is a schematic diagram of setting up a functional separation layer at the cleaning point in Embodiment 3.

[0050] In the figure: 1-Active layer, 2-Functional separation layer, 3-Electrode slot, 4-Sensor, 5-Functional separation layer coating device, 6-Rewinding mechanism. Detailed Implementation

[0051] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0052] Those skilled in the art will understand that the embodiments described are merely illustrative of the invention and should not be construed as limiting the invention.

[0053] Example 1

[0054] This embodiment provides a method for manufacturing a tab-type electrode, including the following steps:

[0055] S1. A current collector is provided, which is a positive electrode current collector aluminum foil with a thickness of 11μm; the surface of the current collector to be coated has a coating area, the coating area includes a cleaning area, and the cleaning area includes cleaning points;

[0056] S2. Depending on the specific requirements, a transverse streak coating is applied to the cleaning area to form a functional separation layer with a thickness of 2μm. After coating, as shown... Figure 5 As shown;

[0057] Based on a 100% mass ratio of the functional separation layer, the functional separation layer comprises 58.80% conductive carbon black (SP), 39.20% adhesive polyacrylic acid (PAA), and 2% magnesium hydroxide (MgO); that is, the mass ratio of conductive materials to adhesive materials is 1:0.67; and the additive accounts for 2% of the total mass of conductive materials and adhesive materials.

[0058] SP, PAA and magnesium hydroxide are stirred in solvent water at a mass ratio of 58.8%:39.2%:2% to obtain a uniform slurry, which is then applied.

[0059] S3. The ternary cathode material, binder and conductive agent are stirred in the solvent N-methylpyrrolidone (NMP) at a mass ratio of 97%:1.6%:1.4% to prepare a uniform cathode slurry.

[0060] An active layer is formed on the coating area using a positive electrode material, covering the existing functional separation layer; the active layer is a positive electrode active layer with a thickness of 120 μm, such that the thickness of the functional separation layer is 0.625% of the thickness of the active layer. After coating the active layer, as shown... Figure 1 As shown;

[0061] S4. Perform laser cleaning on the cleaning area to remove the functional separation layer and the active layer covering it, forming a centrally located tab groove. To ensure the cleaning and separation effect, different laser cleaning powers will be set for different interfaces, taking into account the differences between the active material layer and the functional separation layer. Specifically:

[0062] The laser cleaning process includes a first laser cleaning at a laser power of 1200W to clean the active layer covering the surface of the functional separation layer. At this stage, the functional separation layer can withstand the heat radiation from the high-power cleaning. A second laser cleaning is then performed at a laser power of 750W to clean the transition interface between the functional separation layer and the active layer. At this stage, the layer is thinner, and the lower-power laser ensures a complete functional separation layer. After cleaning, as shown... Figure 2 As shown; a third laser cleaning is performed at a laser power of 300W to clean the functional separation layer. The adhesive materials rapidly vaporize and the conductive agent detaches, revealing the electrode sheet with exposed foil at the tab slot. Finally, a fourth laser cleaning is performed at a laser power of 200W to remove residues on the current collector surface. Ultra-low power cleaning is implemented to finalize the removal of any remaining micro-residues from the previous three cleanings, resulting in a clean electrode sheet with exposed foil at the tab slot. Figure 3 As shown;

[0063] S5. A tab is placed in the tab slot to obtain an electrode plate.

[0064] In the manufacturing method, steps S1 and S2, namely, coating and setting the functional separation layer, are as follows: Figure 4 The manufacturing process is carried out in the shown manufacturing apparatus along the moving and conveying direction of the current collector. The manufacturing apparatus includes a sensor, a functional separation layer coating device, and a winding mechanism arranged in sequence. The sensor is used to detect the position of the functional separation layer and control the functional separation layer coating device to coat and form the functional separation layer at the corresponding position. The winding mechanism is used to wind up the current collector that has formed the functional separation layer.

[0065] Example 2

[0066] The difference from Example 1 is that in step S2, a large rectangular coating is performed on the coating area of ​​the current collector surface, such as... Figure 6 As shown, except for the above, the other conditions are exactly the same as in Example 1.

[0067] Example 3

[0068] The difference from Example 3 is that in step S2, the cleaning points on the surface of the current collector to be coated are selected for precise, intermittent spot coating, such as... Figure 7 As shown, except for the above, the other conditions are exactly the same as in Example 1.

[0069] Example 4

[0070] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 81.67%, the proportion of adhesive material is adjusted from 39.20% to 16.33%, and the proportion of magnesium hydroxide is kept constant at 2%. The mass ratio of conductive agent material to adhesive material is adjusted from 1:0.67 to 1:0.20, and the proportion of the additive in the total mass of conductive agent material and adhesive material remains unchanged at 2%. Except for the above, the other conditions are exactly the same as in Example 1.

[0071] Example 5

[0072] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 65.33%, the proportion of adhesive material is adjusted from 39.20% to 32.67%, and the proportion of magnesium hydroxide is kept constant at 2%. The mass ratio of conductive agent material to adhesive material is adjusted from 1:0.67 to 1:0.50, and the proportion of the additive in the total mass of conductive agent material and adhesive material remains unchanged at 2%. Except for the above, the other conditions are exactly the same as in Example 1.

[0073] Example 6

[0074] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 39.20%, the proportion of adhesive material is adjusted from 39.20% to 58.80%, and the proportion of magnesium hydroxide is kept constant at 2%. The mass ratio of conductive agent material to adhesive material is adjusted from 1:0.67 to 1:1.5, and the proportion of the additive in the total mass of conductive agent material and adhesive material remains unchanged at 2%. Except for the above, the other conditions are exactly the same as in Example 1.

[0075] Example 7

[0076] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 32.67%, the proportion of adhesive material is adjusted from 39.20% to 65.33%, and the proportion of magnesium hydroxide is kept constant at 2%. The mass ratio of conductive agent material to adhesive material is adjusted from 1:0.67 to 1:2, and the proportion of the additive in the total mass of conductive agent material and adhesive material remains unchanged at 2%. Except for the above, the other conditions are exactly the same as in Example 1.

[0077] Example 8

[0078] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 60%, the proportion of adhesive material is adjusted from 39.20% to 40%, and the proportion of magnesium hydroxide additive is adjusted from 2% to 0%, i.e., no additive is used; the mass ratio of conductive agent material to adhesive material remains unchanged at 1:0.67, and the proportion of additive in the total mass of conductive agent material and adhesive material is changed from 2% to 0%, i.e., no additive is used. Except for the above, the other conditions are exactly the same as in Example 1.

[0079] Example 9

[0080] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 59.40%, the proportion of adhesive material is adjusted from 39.20% to 39.60%, and the proportion of magnesium hydroxide additive is adjusted from 2% to 1%. The mass ratio of conductive agent material to adhesive material remains unchanged at 1:0.67, and the proportion of additive in the total mass of conductive agent material and adhesive material changes from 2% to 1%. Except for the above, the other conditions are exactly the same as in Example 1.

[0081] Example 10

[0082] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 57.12%, the proportion of adhesive material is adjusted from 39.20% to 38.08%, and the proportion of magnesium hydroxide additive is adjusted from 2% to 4.8%. The mass ratio of conductive agent material to adhesive material remains unchanged at 1:0.67, and the proportion of additive in the total mass of conductive agent material and adhesive material changes from 2% to 5%. Except for the above, the other conditions are exactly the same as in Example 1.

[0083] Example 11

[0084] The difference from Example 1 is that in step S2, the proportion of conductive agent material in the functional separation layer is adjusted from 58.80% to 56.04%, the proportion of adhesive material is adjusted from 39.20% to 37.36%, and the proportion of magnesium hydroxide additive is adjusted from 2% to 6.6%. The mass ratio of conductive agent material to adhesive material remains unchanged at 1:0.67, and the proportion of additive in the total mass of conductive agent material and adhesive material changes from 2% to 7%. Except for the above, the other conditions are exactly the same as in Example 1.

[0085] Example 12

[0086] The difference from Example 1 is that in step S2, the thickness of the functional separation layer is adjusted from 2 μm to 0.6 μm. Apart from the above, the other conditions are exactly the same as in Example 1.

[0087] Example 13

[0088] The difference from Example 1 is that in step S2, the thickness of the functional separation layer is adjusted from 2μm to 4μm. Apart from the above, the other conditions are exactly the same as in Example 1.

[0089] Example 14

[0090] The difference from Example 1 is that in step S2, the thickness of the functional separation layer is adjusted from 2μm to 8μm. Apart from the above, the other conditions are exactly the same as in Example 1.

[0091] Example 15

[0092] The difference from Example 1 is that in step S2, the thickness of the functional separation layer is adjusted from 2μm to 16μm. Apart from the above, the other conditions are exactly the same as in Example 1.

[0093] Comparative Example 1

[0094] The difference from Example 1 is that no functional separation layer is set, that is, step S2 is not performed, and step S3 is performed directly on the positive current collector. In step S4, only the first laser cleaning and the second laser cleaning are performed. Apart from the above, the other conditions are exactly the same as those in Example 1.

[0095] Characterization and Testing

[0096] 1) Results of residual positive electrode material and aluminum foil perforation:

[0097] Clean the 12mm×22mm vacancy and observe the surface residue using a 100X microscope; residual black spots (dark patches) area ≥2mm². 2 Quantities of 1-5 are recorded as 5 / 10; quantities of ≥6 are recorded as 10 / 10; area < 2 mm 2If the quantity is less than 5, it is recorded as 0 / 10; if the area is less than 2 mm², it is recorded as 1 / 10.

[0098] Clean the 12mm×22mm gap and use a CCD to detect the number of perforation points; if the number of perforations is ≥1, record it as 10 / 10, and if the number of perforations is 0, record it as 0 / 10.

[0099] 2) Welding tensile test: Welding tensile tests were performed on the cleaned positions of the electrode sheets obtained in the examples and comparative examples. The test speed was 500 mm / min, the tensile force direction was perpendicular to the weld joint direction, and the test environment temperature was 25±3℃, humidity ≤60%.

[0100] The results are shown in Table 1.

[0101] Table 1

[0102]

[0103] As can be seen from Table 1:

[0104] The functional separation layer in the manufacturing method of this invention can be flexibly configured. It can be applied to a large area corresponding to the active material coating area, or to a horizontal streak coating corresponding to the cleaning area, or to a precise spot coating corresponding to the cleaning points. Regardless of the method, after laser cleaning at the location requiring cleaning, the active material and the foil (current collector) are completely separated, resulting in high cleanliness and simpler processing. It can efficiently peel off the adhesion between the active layer and the current collector during laser cleaning, reducing the residual active material on the current collector surface to varying degrees, and has no adverse effects on the thickness of the electrode sheet, interface bonding, etc., which can effectively improve the effectiveness and reliability of the middle electrode tab welding.

[0105] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0106] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0107] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for manufacturing a tab-type electrode, characterized in that, Includes the following steps: A current collector is provided, wherein the surface of the current collector to be coated has a coating area, the coating area includes a cleaning area, and the cleaning area includes cleaning points; A functional separation layer is formed on any one of the cleaning points, cleaning areas, or coating areas; the functional separation layer comprises conductive agent materials and adhesive materials, and the mass of the conductive agent materials accounts for 38% to 67% of the mass of the functional separation layer; An active layer is formed on the coating area, covering the existing functional separation layer; Laser cleaning is performed on the cleaning points or the cleaning area to remove the functional separation layer and the active layer covering it, forming tab grooves; A tab is provided in the tab slot to obtain an electrode plate.

2. The method for manufacturing the tab-type electrode sheet according to claim 1, characterized in that, The resistance of the current collector is less than 2mΩ; And / or the tabs include a centrally located tab.

3. The method for manufacturing the tab-type electrode sheet according to claim 1, characterized in that, The adhesive material accounts for 28% to 62% of the mass of the functional separation layer; And / or, the mass ratio of the conductive agent material to the adhesive material is 1:(0.5~1.5).

4. The method for manufacturing the tab-type electrode sheet according to claim 1, characterized in that, The thickness of the functional separation layer is 0.5% to 50% of the thickness of the active layer; And / or, the thickness of the functional separation layer is 0.5μm~2μm.

5. The method for manufacturing the tab-type electrode sheet according to claim 1, characterized in that, The functional separation layer also includes an auxiliary agent, which includes at least one of magnesium hydroxide, calcium hydroxide, or aluminum hydroxide. And / or, the mass of the additive accounts for 0% to 5% of the total mass of the conductive agent material and the adhesive material.

6. The method for manufacturing the tab-type electrode sheet according to claim 1, characterized in that, The electrode plates include positive electrode plates or negative electrode plates; And / or, the positive electrode sheet includes a positive electrode active material, which includes at least one of ternary materials, lithium iron phosphate, lithium manganese oxide, lithium manganese iron phosphate, or lithium cobalt oxide; And / or, the conductive agent material includes at least one of acetylene black, Ketjen black, conductive carbon black, or carbon nanotubes; And / or, the adhesive material includes at least one of styrene-butadiene rubber, polyacrylic acid, polyimide, or polyvinylidene fluoride.

7. The method for manufacturing the tab-type electrode sheet according to claim 1, characterized in that, The laser cleaning process includes a first laser cleaning, a second laser cleaning, a third laser cleaning, and a fourth laser cleaning. The first laser cleaning is used to clean the active layer covering the surface of the functional separation layer. The second laser cleaning is used to clean the transition interface between the functional separation layer and the active layer. The third laser cleaning is used to clean the functional separation layer. The fourth laser cleaning is used to clean the residue on the surface of the current collector. And / or, the power of the first laser cleaning is 800W~1600W, the power of the second laser cleaning is 500W~1000W, the power of the third laser cleaning is 100W~500W, and the power of the fourth laser cleaning is 100W~300W.

8. An electrode sheet, characterized in that, Obtained by the manufacturing method according to any one of claims 1-7.

9. A battery, characterized in that, It contains the battery electrode as described in claim 8.

10. An apparatus for manufacturing tab-type electrode sheets, characterized in that, The manufacturing apparatus is used to operate the manufacturing method according to any one of claims 1-8. Along the moving and conveying direction of the current collector, the manufacturing apparatus includes a sensor, a functional separation layer coating device and a winding mechanism arranged in sequence. The sensor is used to detect the position of the functional separation layer and control the functional separation layer coating device to coat and form the functional separation layer at the corresponding position. The winding mechanism is used to wind up the current collector that has formed the functional separation layer.

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