Pole piece manufacturing device, pole piece and manufacturing method thereof

Abstract

The invention relates to a pole piece manufacturing device, a pole piece and a manufacturing method of the pole piece. The pole piece manufacturing device comprises a rolling mechanism, a thickness detection mechanism and a laser cleaning mechanism. And the rolling mechanism is used for rolling the active material film layer and the current collector, so that the active material film layer and the current collector are compounded to form the pole piece. And the thickness detection mechanism is arranged at the downstream of the rolling mechanism and is used for detecting the thickness value of the pole piece. The laser cleaning mechanism is arranged at the downstream of the thickness detection mechanism and connected to the thickness detection mechanism, and the laser cleaning mechanism is configured to irradiate laser towards the active substance film layer according to the thickness value so that the thickness of the pole piece can reach a target value. According to the pole piece manufacturing device provided by the invention, the laser cleaning mechanism can irradiate the laser towards the active substance film layer according to the thickness value so as to precisely adjust the thickness of the pole piece, so that the precision of the pole piece is improved, and the thickness consistency of the pole piece is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery production, and in particular to a pole piece manufacturing device, a pole piece and a manufacturing method thereof. Background Art

[0002] Battery monomers are widely used in electronic devices, such as mobile phones, laptop computers, battery cars, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and electric tools, etc. Battery monomers may include nickel-cadmium batteries, nickel-hydrogen batteries, lithium-ion batteries, and secondary alkaline zinc-manganese batteries, etc.

[0003] In the development of batteries, the thickness of pole pieces varies greatly. In the process of manufacturing battery cells, uneven stress is easily generated, leading to internal rupture of the battery cells. Therefore, the consistency of pole piece thickness is crucial. Summary of the invention

[0004] The present application provides a pole piece manufacturing device, a pole piece and a manufacturing method thereof, aiming to improve the thickness consistency of the pole piece to a certain extent.

[0005] In the first aspect, the present application proposes a pole piece manufacturing device, which includes a rolling mechanism, a thickness detection mechanism and a laser cleaning mechanism. The rolling mechanism is used to roll the active material film layer and the current collector so that the active material film layer and the current collector are composited to form a pole piece. The thickness detection mechanism is arranged downstream of the rolling mechanism and is used to detect the thickness value of the pole piece. The laser cleaning mechanism is arranged downstream of the thickness detection mechanism and is connected to the thickness detection mechanism. The laser cleaning mechanism is configured to irradiate a laser toward the active material film layer according to the thickness value so that the thickness of the pole piece reaches the target value.

[0006] The pole piece manufacturing device provided in the present application combines a thickness detection mechanism and a laser cleaning mechanism with a rolling mechanism, measures the thickness value of the pole piece after rolling, and irradiates the active material film layer with a laser based on the thickness value to reduce the thickness of the pole piece after rolling, so that the thickness of the pole piece is thinner, and the manufacture of extremely thin pole pieces under a certain compaction density is realized. Moreover, the laser cleaning mechanism can irradiate the laser toward the active material film layer according to the thickness value to accurately adjust the thickness of the pole piece, thereby improving the accuracy of the pole piece and improving the thickness consistency of the pole piece. In addition, without changing the main mechanism of the original pole piece manufacturing device, a thickness detection mechanism and a laser cleaning mechanism are added to minimize the impact on the original pole piece manufacturing device, and the original pole piece manufacturing device is used to the greatest extent, thereby effectively reducing costs.

[0007] According to one embodiment of the present application, the laser cleaning mechanism is configured to be able to reduce the thickness of the pole piece to less than or equal to 50 μm.

[0008] In these optional embodiments, the thickness of the pole piece after laser irradiation can reach 50 μm or thinner, and the thickness consistency of the pole piece is high.

[0009] According to one embodiment of the present application, the laser includes continuous laser and / or pulse laser.

[0010] In these optional embodiments, continuous laser can continuously output energy, and can achieve rapid and uniform thinning when acting on a large area of ​​active material film. Pulsed laser has a short pulse width and highly concentrated laser energy, and can accurately act on microscopic areas and specific areas of the active material film, and can more accurately control the degree of reduction of the coating thickness.

[0011] According to one embodiment of the present application, the power of the continuous laser is 1000W to 10000W.

[0012] In these optional embodiments, the power of the laser during the laser cleaning process is adjusted according to the thickness value, so as to control the thickness of the active material film layer on the surface penetrated by the laser, and then control the thickness of the pole piece. The power of the continuous laser is 1000w to 10000w, which can improve the defects of uneven thickness of the active material film layer and decreased density of the active material film layer caused by too low continuous laser power. It can also improve the performance of the current collector and the active material film layer affected by too high continuous laser power.

[0013] According to one embodiment of the present application, the power of the pulse laser is 1000w to 4000w.

[0014] In these optional embodiments, the power of the pulsed laser is 1000W to 4000W, which can improve the defect that the thickness of the active material film layer is uneven due to the low pulsed laser power, and it is difficult to meet the expected thickness. It can also improve the defect that the pulsed laser power is too high, forming heat accumulation in the active material film layer and the current collector, and damaging the active material film layer and the current collector.

[0015] According to one embodiment of the present application, when the laser cleaning mechanism is configured to reduce the thickness of the pole piece to less than or equal to 50 μm, the power of the continuous laser is 3000W to 10000W.

[0016] According to one embodiment of the present application, when the laser cleaning mechanism is configured to reduce the thickness of the pole piece to less than or equal to 50 μm, the power of the pulsed laser is 2000W to 4000W.

[0017] According to one embodiment of the present application, the pole piece running distance between the thickness detection mechanism and the laser cleaning mechanism is 1m to 3m.

[0018] In these optional embodiments, a thickness detection mechanism is used to detect the thickness value of the pole piece, and these data are transmitted to the laser cleaning mechanism in real time. There is a tape running distance of 1m to 3m between the laser cleaning mechanism and the thickness detection mechanism, and the tape running distance is also synchronously input into the laser cleaning machine. Therefore, the laser cleaning machine can accurately calculate the start time of the action for the thickness value signal, so that the position of the laser irradiation is consistent with the position of the thickness measurement, thereby achieving efficient and accurate laser irradiation.

[0019] According to an embodiment of the present application, the thickness detection mechanism is configured to detect the lateral thickness and longitudinal thickness of the pole piece.

[0020] In these optional embodiments, the transverse thickness and the longitudinal thickness are detected to comprehensively monitor the uniformity of the pole piece thickness, thereby improving the consistency of the pole piece thickness.

[0021] According to one embodiment of the present application, the thickness detection mechanism is a laser scanning thickness gauge.

[0022] In these optional embodiments, the laser scanning thickness gauge can accurately measure the transverse thickness and longitudinal thickness of the pole piece with high accuracy and speed.

[0023] In a second aspect, the present application provides a method for manufacturing a pole piece, comprising: Rolling the active material film layer and the current collector to form a pole piece by combining the active material film layer and the current collector; Detect the thickness of the pole piece; According to the thickness value, the active material film layer of the pole piece is irradiated with laser so that the thickness of the pole piece reaches the target value.

[0024] The pole piece manufacturing method provided in the present application measures the thickness value of the pole piece after rolling, and irradiates the active material film layer with laser based on the thickness value to reduce the thickness of the pole piece after rolling, so that the thickness of the pole piece is thinner, and realizes the manufacturing of extremely thin pole pieces under a certain compaction density. The thickness of the pole piece can also be accurately adjusted to improve the thickness consistency of the pole piece.

[0025] According to one embodiment of the present application, irradiating the active material film layer with laser according to the thickness value includes: Irradiating the active material film layer with continuous laser light; When there is a region of the pole piece having a thickness greater than a predetermined value, the region of the pole piece having a thickness greater than the predetermined value is irradiated with a pulse laser, and the predetermined value is greater than a target value.

[0026] In a third aspect, the present application provides a pole piece manufactured according to the aforementioned pole piece manufacturing method.

[0027] The pole piece provided in the present application is applied to a battery cell, which improves the problem that large thickness differences of the pole piece may easily cause uneven stress and lead to internal rupture of the battery cell during the manufacturing process of the battery cell, thereby improving the reliability of the battery cell.

[0028] According to one embodiment of the present application, the thickness of the pole piece is less than or equal to 50 μm.

[0029] According to one embodiment of the present application, the pole piece is a dry pole piece.

[0030] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0032] Figure 1 It is a structural schematic diagram of a pole piece manufacturing device provided in one embodiment of the present application.

[0033] The drawings are not necessarily drawn to scale.

[0034] Description of reference numerals: 1. Active material film layer; 2. Current collector; 3. Pole piece; 100. Pole piece manufacturing device; 10. Rolling mechanism; 20. Thickness detection mechanism; 30. Laser cleaning mechanism; 40. Guide roller. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0036] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0037] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0038] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0040] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0041] The term “plurality” used in this application refers to two or more (including two).

[0042] At present, judging from the development of the market situation, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields.

[0043] A battery device generally refers to a single physical module that includes multiple battery cells to provide higher voltage and capacity. A battery cell may be the smallest unit that constitutes a battery device.

[0044] In the related art, in the process of making pole pieces by rolling, the gap between the two rollers in the rolling mechanism becomes the key factor in controlling the consistency of the pole piece thickness. However, in the actual process, factors such as the accuracy of the roll gap measurement, the driving accuracy, and the accuracy of the transmission components limit the stability of the roll gap, causing the roll gap to fluctuate within the range of 10μm, which also causes the thickness of the pole piece to fluctuate within the range of about 10μm, ultimately resulting in large differences in the thickness of the pole piece.

[0045] The pole piece manufacturing device provided in the present application combines a thickness detection mechanism and a laser cleaning mechanism with a rolling mechanism, measures the thickness value of the pole piece after rolling, and irradiates the active material film layer with a laser based on the thickness value to reduce the thickness of the pole piece after rolling, so that the thickness of the pole piece is thinner, and the manufacture of extremely thin pole pieces under a certain compaction density is realized. Moreover, the laser cleaning mechanism can irradiate the laser toward the active material film layer according to the thickness value to accurately adjust the thickness of the pole piece, thereby improving the accuracy of the pole piece and improving the thickness consistency of the pole piece. In addition, without changing the main mechanism of the original pole piece manufacturing device, a thickness detection mechanism and a laser cleaning mechanism are added to minimize the impact on the original pole piece manufacturing device, and the original pole piece manufacturing device is used to the greatest extent, thereby effectively reducing costs.

[0046] The pole piece manufacturing device described in the embodiment of the present application is used to manufacture pole pieces, which are applied to battery cells, which are applied to battery devices and electrical devices using batteries. The battery cells can be used for, but not limited to, batteries, and can also be used for vehicles, aircraft, ships, electronic equipment, electric tools and other products, which can improve the reliability of these products.

[0047] In some embodiments, a battery device may include one or more battery cell assemblies to provide voltage and capacity.

[0048] The battery cell assembly may include a plurality of battery cells, and the plurality of battery cells are connected in series, in parallel or in hybrid connection through a busbar component. Hybrid connection means that the plurality of battery cells are connected in both series and in parallel.

[0049] The battery cell may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0050] As an example, the battery cells may be lithium ion battery cells, sodium ion battery cells, sodium lithium ion battery cells, lithium metal battery cells, sodium metal battery cells, lithium sulfur battery cells, magnesium ion battery cells, nickel hydrogen battery cells, nickel cadmium battery cells, lead storage battery cells, etc.

[0051] As an example, the battery cell may be a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a polygonal battery cell, such as a hexagonal battery cell.

[0052] In some embodiments, there are multiple battery cells, and the multiple battery cells are first connected in series, in parallel, or in mixed connection to form a battery module. The multiple battery modules are then connected in series, in parallel, or in mixed connection to form a whole, and are contained in a box.

[0053] Multiple battery cells in a battery module can be electrically connected through a busbar component to achieve parallel connection, series connection or mixed connection of multiple battery cells in the battery module. There can be one or more busbar components, each of which is used to electrically connect at least two battery cells.

[0054] An embodiment of the present application provides a battery cell, which includes a housing and an electrode assembly accommodated in the housing.

[0055] The electrode assembly is the part in the battery cell where the electrochemical reaction occurs. One or more electrode assemblies may be contained in the housing.

[0056] In some embodiments, the electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator. The positive electrode sheet has opposite polarity to the negative electrode sheet, and the separator separates the positive electrode sheet from the negative electrode sheet.

[0057] At least part of the separator is located between the positive electrode sheet and the negative electrode sheet. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and released back and forth between the positive electrode sheet and the negative electrode sheet. The separator is arranged between the positive electrode sheet and the negative electrode sheet to prevent the positive and negative electrodes from short-circuiting, while allowing the active ions to pass through.

[0058] In some embodiments, the positive electrode sheet may include a positive electrode current collector and a positive electrode active material film layer disposed on at least one surface of the positive electrode current collector.

[0059] As an example, the positive electrode current collector has two surfaces opposite to each other in its thickness, and the positive electrode active material film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0060] As an example, the positive electrode current collector may be a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal may be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloy, titanium or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0061] As an example, the positive electrode active material film layer includes a positive electrode active material, and the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.8 Co 0.15 Al0.05 O2) and at least one of its modified compounds. The modified compound refers to a substance obtained by modifying the above substances by means of doping or coating.

[0062] In some embodiments, the negative electrode sheet may include a negative electrode current collector.

[0063] As an example, the negative electrode current collector may be a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal may be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloy, titanium or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0064] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material film layer disposed on at least one surface of the negative electrode current collector.

[0065] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material film layer is disposed on any one or both of the two facing surfaces of the negative electrode current collector.

[0066] As an example, the negative electrode active material film layer includes a negative electrode active material, and the negative electrode active material can adopt a negative electrode active material for a battery cell that is well known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material can be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for battery cells can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0067] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0068] See also Figure 1 , Figure 1 It is a structural schematic diagram of a pole piece manufacturing device provided in one embodiment of the present application.

[0069] like Figure 1As shown, the present application proposes a pole piece manufacturing device 100, which includes a rolling mechanism 10, a thickness detection mechanism 20 and a laser cleaning mechanism 30. The rolling mechanism 10 is used to roll the active material film layer 1 and the current collector 2 so that the active material film layer 1 and the current collector 2 are composited to form a pole piece 3. The thickness detection mechanism 20 is arranged downstream of the rolling mechanism 10, and is used to detect the thickness value of the pole piece 3. The laser cleaning mechanism 30 is arranged downstream of the thickness detection mechanism 20 and connected to the thickness detection mechanism 20, and the laser cleaning mechanism 30 is configured to irradiate a laser toward the active material film layer 1 according to the thickness value so that the thickness of the pole piece 3 reaches the target value.

[0070] The rolling mechanism 10 can be used to form a positive electrode sheet, that is, it can be a positive electrode sheet rolling mechanism 10 ; the rolling mechanism 10 can be used to form a negative electrode sheet, that is, it can be a negative electrode sheet rolling mechanism 10 .

[0071] In some examples, the rolling mechanism 10 includes a support frame, a first pressing roller and a second pressing roller, both of which are rotatably disposed on the support frame, the first pressing roller and the second pressing roller are disposed opposite to each other, the active material film layer 1 and the current collector 2 pass through the roller gap between the first pressing roller and the second pressing roller, and the first pressing roller and the second pressing roller cooperate to extrude the active material film layer 1 and the current collector 2 to compound the active material film layer 1 and the current collector 2 to form a pole piece 3.

[0072] Optionally, the first pressing roller and the second pressing roller are arranged on the moving path of the active material film layer 1 and the current collector 2, the current collector 2 includes a first surface and a second surface that are opposite to each other, the active material film layer 1 is arranged on both sides of the current collector 2, that is, the first active material film layer 1 is arranged opposite to the first surface, and the second active material film layer 1 is arranged opposite to the second surface, the first pressing roller contacts the side of the first active material film layer 1 away from the first surface, and the second pressing roller contacts the side of the second active material film layer 1 away from the second surface, and the active material film layer 1 and the current collector 2 are rolled by the first pressing roller and the second pressing roller to form a pole piece 3.

[0073] Optionally, the active material membrane layer 1 is manufactured by a dry method.

[0074] Optionally, the pole piece 3 is a dry pole piece.

[0075] In some examples, the thickness of the pole piece 3 formed by rolling is less than or equal to 100 μm and greater than 60 μm.

[0076] Optionally, the thickness of the pole piece 3 formed by rolling is less than or equal to 100 μm and greater than 70 μm.

[0077] Optionally, the thickness of the pole piece 3 formed by rolling is less than or equal to 80 μm and greater than 70 μm.

[0078] Optionally, the thickness of the pole piece 3 formed by rolling is less than or equal to 70 μm and greater than 60 μm.

[0079] In some examples, the thickness detection mechanism 20 includes one or more of a mechanical contact thickness detection mechanism, an optical thickness detection mechanism, a radiation thickness detection mechanism, and an ultrasonic thickness detection mechanism.

[0080] Optionally, a guide roller 40 is provided between the rolling mechanism 10 and the thickness detection mechanism 20 , and the guide roller 40 is used to change the running direction of the pole piece 3 .

[0081] The laser cleaning mechanism 30 is disposed downstream of the thickness detection mechanism 20 and connected to the thickness detection mechanism 20 .

[0082] In some examples, the laser cleaning mechanism 30 is connected to the thickness detection mechanism 20 by wire.

[0083] In some other examples, the laser cleaning mechanism 30 is wirelessly connected to the thickness detection mechanism 20 .

[0084] Optionally, the laser cleaning mechanism 30 is electrically connected to the thickness detection mechanism 20 and receives a thickness value signal from the thickness detection mechanism 20 .

[0085] The laser cleaning mechanism 30 is configured to irradiate the laser toward the active material film layer 1, and the active material film layer 1 absorbs a certain amount of energy, and the film particles are gasified, sublimated and vibrated, etc., so that the thickness of the active material film layer 1 is reduced. Therefore, on the basis of the thickness of the pole piece 3 formed by rolling by the rolling mechanism 10, the thickness of the pole piece 3 is further reduced to meet the actual production needs and further meet the manufacturing requirements of the ultra-thin pole piece 3.

[0086] The laser cleaning mechanism 30 is configured to irradiate laser light toward the active material film layer 1 according to the thickness value, so that the thickness of the pole piece 3 reaches a target value.

[0087] Optionally, the target value of the thickness of the pole piece 3 after laser irradiation is less than or equal to 70 μm.

[0088] In some examples, the laser cleaning mechanism 30 uses one or more of pulse laser, continuous laser, compound laser and ultraviolet laser.

[0089] In some examples, the laser cleaning mechanism 30 is configured to irradiate lasers of different powers toward the active material film layer 1 according to the thickness value.

[0090] In some examples, the laser cleaning mechanism 30 is configured to irradiate different types of lasers toward the active material film layer 1 according to the thickness value.

[0091] First, the active material film layer 1 and the current collector 2 are compounded to form the pole piece 3 by the rolling mechanism 10, and the pole piece 3 is squeezed to have a predetermined thickness, and then the thickness of the pole piece 3 is further reduced by the laser cleaning mechanism 30. The target thickness of the pole piece 3 cannot be directly obtained by using the laser cleaning mechanism 30 alone. The rolling mechanism 10 cooperates with the laser cleaning mechanism 30. In the first stage, rough adjustment is performed to form the pole piece 3 and complete the basic thickness molding. In the second stage, the pole piece 3 is thinned and the thickness is finely adjusted to achieve thickness uniformity.

[0092] The pole piece manufacturing device 100 provided in the present application combines the rolling mechanism 10 with the thickness detection mechanism 20 and the laser cleaning mechanism 30 to measure the thickness value of the pole piece 3 after rolling, and irradiates the active material film layer 1 with laser based on the thickness value to reduce the thickness of the pole piece 3 after rolling, so that the thickness of the pole piece 3 is thinner, and the manufacture of an extremely thin pole piece 3 under a certain compaction density is realized. Moreover, the laser cleaning mechanism 30 can irradiate the laser toward the active material film layer 1 according to the thickness value to accurately adjust the thickness of the pole piece 3, thereby improving the accuracy of the pole piece 3 and improving the thickness consistency of the pole piece 3. In addition, without changing the main mechanism of the original pole piece manufacturing device, the thickness detection mechanism 20 and the laser cleaning mechanism 30 are added to minimize the impact on the original pole piece manufacturing device, and the original pole piece manufacturing device is used to the greatest extent, thereby effectively reducing costs.

[0093] According to one embodiment of the present application, the laser cleaning mechanism is configured to be able to reduce the thickness of the pole piece to less than or equal to 50 μm.

[0094] During the production of the pole piece 3, the roller gap of the rolling mechanism 10 is adjusted so that the thickness of the pole piece 3 after rolling is greater than the target value of the pole piece 3, and laser is irradiated to remove the thickness difference between the target value and the thickness value.

[0095] Optionally, the laser cleaning mechanism 30 is configured to be able to reduce the thickness of the pole piece 3 to less than or equal to 50 μm and greater than 20 μm.

[0096] In some examples, the thickness of the pole piece 3 formed by rolling is greater than or equal to 70 μm.

[0097] In these optional embodiments, the thickness of the pole piece 3 after laser irradiation can reach 50 μm or thinner, and the thickness consistency of the pole piece 3 is high.

[0098] According to one embodiment of the present application, the laser includes continuous laser and / or pulse laser.

[0099] In some examples, the laser includes a continuous laser.

[0100] Optionally, when the thickness of the pole piece 3 after laser irradiation reaches a target value and the difference between the target value and the thickness value of the pole piece 3 is less than or equal to 30 μm, the laser cleaning mechanism 30 uses continuous laser.

[0101] In some examples, the laser includes a pulsed laser.

[0102] Optionally, when the thickness of the pole piece 3 after laser irradiation reaches a target value and the difference between the target value and the thickness value of a partial area of ​​the pole piece 3 is less than or equal to 5 μm, the laser cleaning mechanism 30 uses a pulsed laser.

[0103] In some examples, the laser includes a continuous laser and a pulsed laser.

[0104] Optionally, when the difference between the target value and the thickness value of the pole piece 3 is greater than 30 μm, the laser cleaning mechanism 30 uses continuous laser and pulsed laser.

[0105] Optionally, the laser uses a composite laser cleaning machine.

[0106] More optionally, the composite laser cleaning machine includes dual laser heads, one laser head emitting continuous laser light and the other emitting pulsed laser light.

[0107] In these optional embodiments, the continuous laser can continuously output energy, and can achieve rapid and uniform thinning when acting on a large area of ​​the active material film layer 1. The pulse width of the pulsed laser is short, and the laser energy is highly concentrated, which can accurately act on the microscopic area and specific area of ​​the active material film layer 1, and can more accurately control the degree of reduction of the coating thickness.

[0108] According to one embodiment of the present application, the power of the continuous laser is 1000W to 10000W.

[0109] In some examples of the present application, the power of the continuous laser is 1000 W, 1200 W, 1400 W, 1600 W, 1800 W, 2000 W, 2200 W, 2400 W, 2600 W, 2800 W, 3000 W, 3200 W, 3400 W, 3600 W, 3800 W, 4000 W, 4200 W, 4400 W, 4600 W, 4800 W, 5000 W, 5200 W, 5400 W, 5500 W, 5600 W, 5700 W, 5800 W, 5900 W, 6000 W, 6100 W, 6200 W, 6300 W, 6400 W, 6500 W, 6600 W, 6700 W, 6800 W, 7000 W, 7100 W, 7200 W, 7300 W, 7400 W, 7500 W, 7600 W, 7700 W, 7800 W, 7900 W, 8000 W, 8100 W, 8200 W, 8300 W, 8400 W, 8500 W, 8600 W, 8700 W, 8800 W 600W, 5800W, 6000W, 6200W, 6400W, 6600W, 6800W, 7000W, 7200W, 7400W, 7600W, 7800W, 8000W, 8200W, 8400W, 8600W, 8800W, 9000W, 9200W, 9400W, 9600W, 9800W, 10000W or in other ranges formed by any two of the above endpoints.

[0110] Optionally, the power of the continuous laser is 3000w to 6000w.

[0111] In these optional embodiments, the power of the laser during the laser cleaning process is adjusted according to the thickness value, so as to control the thickness of the active material film layer 1 that the laser penetrates the surface, and then control the thickness of the pole piece 3. The power of the continuous laser is 1000w to 10000w, which can improve the defects of uneven thickness of the active material film layer 1 and decreased density of the active material film layer 1 caused by too low continuous laser power. It can also improve the performance of the current collector 2 and the active material film layer 1 affected by too high continuous laser power.

[0112] According to one embodiment of the present application, the power of the pulse laser is 1000w to 4000w.

[0113] In some examples of the present application, the power of the continuous laser is 1000 W, 1200 W, 1400 W, 1600 W, 1800 W, 2000 W, 2200 W, 2400 W, 2600 W, 2800 W, 3000 W, 3200 W, 3400 W, 3600 W, 3800 W, 4000 W or in other ranges formed by any two endpoints above.

[0114] Optionally, the power of the pulse laser is 2000w to 3000w.

[0115] In these optional embodiments, the power of the pulsed laser is 1000w to 4000w, which can improve the defect that the thickness of the active material film layer 1 is uneven and difficult to meet the expected thickness due to the low pulsed laser power. It can also improve the defect that the pulsed laser power is too high, forming heat accumulation in the active material film layer 1 and the current collector 2, and damaging the active material film layer 1 and the current collector 2.

[0116] According to an embodiment of the present application, when the laser cleaning mechanism 30 is configured to reduce the thickness of the pole piece 3 to less than or equal to 50 μm, the power of the continuous laser is 3000W to 10000W.

[0117] Alternatively, the entire active material film layer 1 is irradiated with continuous laser light.

[0118] According to an embodiment of the present application, when the laser cleaning mechanism 30 is configured to be able to reduce the thickness of the pole piece 3 to less than or equal to 50 μm, the power of the pulsed laser is 2000W to 4000W.

[0119] Optionally, the pulse laser irradiates a local area of ​​the active material film layer 1 .

[0120] Optionally, when the laser cleaning mechanism 30 is configured to thin the thickness of the pole piece 3 to less than or equal to 50 μm, the continuous laser irradiates the entire active material film layer 1, and the power of the continuous laser is 3000w to 10000w, and the pulse laser irradiates a part of the active material film layer 1, and the power of the pulse laser is 2000w to 4000w.

[0121] According to one embodiment of the present application, the running distance of the pole piece 3 between the thickness detection mechanism 20 and the laser cleaning mechanism 30 is 1 m to 3 m.

[0122] In some examples, the thickness detection mechanism 20 and the laser cleaning mechanism 30 are spaced apart, and the running distance of the pole piece 3 between the thickness detection mechanism 20 and the laser cleaning mechanism 30 is 1 m to 3 m.

[0123] In some examples of the present application, the walking distance of the pole piece 3 between the thickness detection mechanism 20 and the laser cleaning mechanism 30 is 1m, 1.1m, 1.2m, 1.3m, 1.4m, 1.5m, 1.6m, 1.7m, 1.8m, 1.9m, 2m, 2.1m, 2.2m, 2.3m, 2.4m, 2.5m, 2.6m, 2.7m, 2.8m, 2.9m, 3m or in other ranges formed by any two of the above endpoints.

[0124] Optionally, the running distance of the pole piece 3 between the thickness detection mechanism 20 and the laser cleaning mechanism 30 is 2 m to 3 m.

[0125] In these optional embodiments, the thickness detection mechanism 20 is used to detect the thickness value of the pole piece 3, and these data are transmitted in real time to the laser cleaning mechanism 30. There is a tape running distance of 1m to 3m between the laser cleaning mechanism 30 and the thickness detection mechanism 20, and the tape running distance is also synchronously input into the laser cleaning machine. Therefore, the laser cleaning machine can accurately calculate the start time of the action for the thickness value signal, so that the position of the laser irradiation is consistent with the position of the thickness measurement, thereby achieving efficient and accurate laser irradiation.

[0126] According to an embodiment of the present application, the thickness detection mechanism 20 is configured to detect the transverse thickness and the longitudinal thickness of the pole piece 3 .

[0127] In these optional embodiments, the transverse thickness and the longitudinal thickness are detected to comprehensively monitor the thickness uniformity of the pole piece 3 , thereby improving the consistency of the thickness of the pole piece 3 .

[0128] According to one embodiment of the present application, the thickness detection mechanism 20 is a laser scanning thickness gauge.

[0129] Optionally, the laser scanning thickness gauge is configured to transmit the thickness value of the pole piece 3 monitored in real time to the laser cleaning mechanism 30 .

[0130] In these optional embodiments, the laser scanning thickness gauge can accurately measure the transverse thickness and longitudinal thickness of the pole piece 3 with high measurement accuracy and speed.

[0131] In a second aspect, the present application provides a method for manufacturing a pole piece, comprising: The active material film layer and the current collector are rolled to form a pole piece by combining the active material film layer and the current collector.

[0132] Detect the thickness of the pole piece.

[0133] According to the thickness value, the active material film layer of the pole piece is irradiated with laser so that the thickness of the pole piece reaches the target value.

[0134] In some examples, the thickness value of the pole piece is detected by a thickness detection mechanism.

[0135] Optionally, the thickness detector detects the transverse thickness and longitudinal thickness of the pole piece.

[0136] Optionally, a target value of the thickness of the pole piece is less than or equal to 50 μm.

[0137] The pole piece manufacturing method provided in the present application measures the thickness value of the pole piece after rolling, and irradiates the active material film layer with laser based on the thickness value to reduce the thickness of the pole piece after rolling, so that the thickness of the pole piece is thinner, and realizes the manufacturing of extremely thin pole pieces under a certain compaction density. The thickness of the pole piece can also be accurately adjusted to improve the thickness consistency of the pole piece.

[0138] According to an embodiment of the present application, irradiating the active material film layer with laser according to the thickness value includes: irradiating the active material film layer with continuous laser.

[0139] When there is a region of the pole piece having a thickness greater than a predetermined value, the region of the pole piece having a thickness greater than the predetermined value is irradiated with a pulse laser, and the predetermined value is greater than a target value.

[0140] The roller gap of the rolling mechanism is adjusted, and the thickness of the pole piece formed by rolling the active material film layer and the current collector is preset as a predetermined value. The thickness of the pole piece after laser irradiation is the target value, and the predetermined value is greater than the target value. However, in the actual rolling process, the roller gap measurement, drive, and transmission component accuracy are limited, so the roller gap will fluctuate within the range of 10μm, so the thickness of the pole piece fluctuates within the range of about 10μm. Normally, the minimum thickness of the pole piece after rolling by the rolling mechanism can reach 70μm.

[0141] In some examples of the present application, the thickness of the pole piece formed by rolling is 70μm, 71μm, 72μm, 73μm, 74μm, 75μm, 76μm, 77μm, 78μm, 79μm, 80μm, 81μm, 82μm, 83μm, 84μm, 85μm, 86μm, 87μm, 88μm, 89μm, 90μm, 91μm, 92μm, 93μm, 94μm, 95μm, 96μm, 97μm, 98μm, 99μm, 100μm or in other ranges formed by any two endpoints mentioned above.

[0142] In some examples, the thickness of the pole piece detected by the thickness detection mechanism is about 75 μm, the predetermined value is 80 μm, the active material film layer of the pole piece is irradiated with continuous laser, and the pole piece target value is 60 μm. The power of the continuous laser is 1000W to 10000W.

[0143] In some examples, the thickness of the pole piece detected by the thickness detection mechanism is about 70 μm, the predetermined value is 75 μm, the active material film layer of the pole piece is irradiated with continuous laser, and the pole piece target value is 50 μm. The power of the continuous laser is 3000W to 10000W.

[0144] In some examples, the thickness detection mechanism detects that the thickness of the pole piece is between about 70 μm and 80 μm. When the predetermined value is 75 μm, the active material film layer of the pole piece is irradiated with a continuous laser, and the portion of the pole piece whose thickness is greater than the predetermined value is irradiated with a pulsed laser. The pole piece target value is 60 μm. The power of the continuous laser is 1000w to 10000w. The power of the pulsed laser is 1000w to 4000w.

[0145] In some examples, the thickness detection mechanism detects that the thickness of the pole piece is between about 72 μm and 68 μm. When the predetermined value is 70 μm, the active material film layer of the pole piece is irradiated with a continuous laser, and the portion of the pole piece whose thickness is greater than the predetermined value is irradiated with a pulsed laser. The pole piece target value is 50 μm. The power of the continuous laser is 3000w to 10000w. The power of the pulsed laser is 2000w to 4000w.

[0146] In a third aspect, the present application provides a pole piece manufactured according to the aforementioned pole piece manufacturing method.

[0147] The pole piece provided in the present application is applied to a battery cell, which improves the problem that large thickness differences of the pole piece may easily cause uneven stress and lead to internal rupture of the battery cell during the manufacturing process of the battery cell, thereby improving the reliability of the battery cell.

[0148] According to one embodiment of the present application, the thickness of the pole piece is less than or equal to 50 μm.

[0149] Optionally, the thickness of the pole piece is less than or equal to 50 μm and greater than 20 μm.

[0150] In some examples, the thickness of the pole piece is 20μm, 21μm, 22μm, 23μm, 24μm, 25μm, 26μm, 27μm, 28μm, 29μm, 30μm, 31μm, 32μm, 33μm, 34μm, 35μm, 36μm, 37μm, 38μm, 39μm, 40μm, 41μm, 42μm, 43μm, 44μm, 45μm, 46μm, 47μm, 48μm, 49μm, 50μm or in other ranges formed by any two endpoints mentioned above.

[0151] According to one embodiment of the present application, the pole piece is a dry pole piece.

[0152] Dry-process electrodes are manufactured using dry-process equipment, which mainly manufactures electrodes by rolling, in which the gap between the two rollers becomes a key factor in controlling the consistency of the membrane thickness. However, due to the influence of factors such as measurement accuracy, the stability of the gap is poor, which ultimately causes large differences in the thickness of the electrode. Therefore, by detecting the thickness of the electrode after rolling and irradiating the active material film layer with laser according to the thickness value, it is possible to manufacture extremely thin electrode sheets at a certain compaction density, and the thickness of the electrode sheet can also be accurately adjusted to improve the thickness consistency of the electrode sheet.

[0153] According to some embodiments of the present application, see Figure 1 As shown, the present application provides a pole piece manufacturing device, which includes a rolling mechanism, a thickness detection mechanism and a laser cleaning mechanism.

[0154] The rolling mechanism is used to roll the active material film layer and the current collector so that the active material film layer and the current collector are combined to form a pole piece. The thickness of the pole piece formed by rolling is less than or equal to 80 μm and greater than 70 μm.

[0155] The thickness detection mechanism is arranged downstream of the rolling mechanism and is used to detect the thickness value of the pole piece. The thickness detection mechanism is configured to detect the transverse thickness and longitudinal thickness of the pole piece. The thickness detection mechanism is a laser scanning thickness gauge.

[0156] The laser cleaning mechanism is arranged downstream of the thickness detection mechanism and connected to the thickness detection mechanism. The walking distance of the pole piece between the thickness detection mechanism and the laser cleaning mechanism is 1m to 3m. The laser cleaning mechanism is configured to irradiate the laser toward the active material film layer according to the thickness value. The laser includes a continuous laser and a pulsed laser. In the case where the thickness of the pole piece after laser irradiation is less than or equal to 50μm, the power of the continuous laser is 3000w to 10000w. In the case where the laser cleaning mechanism is configured to thin the thickness of the pole piece to less than or equal to 50μm, the power of the pulsed laser is 2000w to 4000w. The thickness of the pole piece after laser irradiation is less than or equal to 50μm.

[0157] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A pole piece manufacturing device, characterized in that: include: A rolling mechanism, used for rolling the active material film layer and the current collector, so that the active material film layer and the current collector are combined to form a pole piece; A thickness detection mechanism, disposed downstream of the rolling mechanism, for detecting the thickness value of the pole piece; A laser cleaning mechanism is disposed downstream of the thickness detection mechanism and connected to the thickness detection mechanism, and the laser cleaning mechanism is configured to irradiate laser toward the active material film layer according to the thickness value so that the thickness of the pole piece reaches a target value.

2. The pole piece manufacturing device according to claim 1, characterized in that: The laser cleaning mechanism is configured to reduce the thickness of the pole piece to less than or equal to 50 μm.

3. The pole piece manufacturing device according to claim 1, characterized in that: The laser includes a continuous laser and / or a pulsed laser.

4. The pole piece manufacturing device according to claim 3, characterized in that: The power of the continuous laser is 1000W to 10000W; and / or, The power of the pulse laser is 1000w to 4000w.

5. The pole piece manufacturing device according to claim 4, characterized in that: When the laser cleaning mechanism is configured to reduce the thickness of the pole piece to less than or equal to 50 μm, the power of the continuous laser is 3000W to 10000W; and / or, When the laser cleaning mechanism is configured to reduce the thickness of the pole piece to less than or equal to 50 μm, the power of the pulse laser is 2000W to 4000W.

6. The pole piece manufacturing device according to claim 1, characterized in that: The pole piece running distance between the thickness detection mechanism and the laser cleaning mechanism is 1m to 3m.

7. The pole piece manufacturing device according to claim 1, characterized in that: The thickness detection mechanism is configured to detect the transverse thickness and the longitudinal thickness of the pole piece.

8. The pole piece manufacturing device according to claim 1, characterized in that: The thickness detection mechanism is a laser scanning thickness gauge.

9. A method for manufacturing a pole piece, characterized in that: include: Rolling the active material film layer and the current collector to form a pole piece by combining the active material film layer and the current collector; Detecting the thickness of the pole piece; According to the thickness value, the active material film layer is irradiated with laser so that the thickness of the pole piece reaches the target value.

10. The pole piece manufacturing method according to claim 9, characterized in that: The irradiating the active material film layer with laser according to the thickness value comprises: irradiating the active material film layer with continuous laser light; In the case where there is a region of the pole piece having a thickness greater than a predetermined value, the region of the pole piece having a thickness greater than the predetermined value is irradiated with a pulse laser, and the predetermined value is greater than a target value.

11. A pole piece, characterized in that: The pole piece manufacturing method according to claim 9 or 10 is manufactured.

12. The pole piece according to claim 11, characterized in that: The thickness of the pole piece is less than or equal to 50 μm.

13. The pole piece according to claim 11, characterized in that: The electrode is a dry electrode.

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