Composite current collector, battery pole piece, battery and electric equipment
By using the insulating base layer and metal layer of composite fluid-collection in the electrode cutting position of the lithium-ion battery, the problem of pole burrs piercing the diaphragm is solved, improving battery safety and reducing production costs.
Patent Information
- Application Number
- CN202323318743.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-06
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2033-12-06
AI Technical Summary
In the prior art, the burrs in the cutting position of the lithium-ion battery pole plate are prone to pierce the diaphragm, which poses a safety hazard, and the existing solutions are complex in process, cumbersome in materials, and high in cost.
Using a composite fluid collector, including an insulating base layer and a metal layer, the second area of the insulating base layer is used to be arranged corresponding to the cutting position of the pole sheet to form a burr-free feeding and finishing position to prevent burrs from piercing the diaphragm.
It effectively improves the safety of the battery, avoids the positive and negative electrode conduction caused by burrs piercing the diaphragm, and reduces production costs and waste.
Smart Images
Figure CN222282063U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of batteries, and specifically relates to a composite current collector, a battery pole piece, a battery and electrical equipment. Background Art
[0002] As a new type of secondary battery, lithium-ion battery has the advantages of high energy density and power density, high operating voltage, light weight, small size, long cycle life, good safety, and green environmental protection. It has broad application prospects in portable appliances, power tools, large-scale energy storage, electric transportation power supply, etc.
[0003] At present, there are port burrs at the cutting position of the pole piece. After the battery cell is made, the burrs can easily pierce the diaphragm to conduct the positive and negative electrodes, posing a safety hazard. In order to solve the above problems, in the prior art, protective glue is mainly set at the cutting position of the pole piece, or by increasing the thickness of the diaphragm, or by setting a ceramic coating on the diaphragm, to play a protective role and prevent the diaphragm from being pierced. However, the above methods have the disadvantages of complex process, cumbersome materials and high material cost. Utility Model Content
[0004] One of the purposes of the utility model is to provide a composite current collector in view of the deficiencies of the prior art, so as to solve the problem that the burrs at the cutting position of the pole piece in the prior art may cause the diaphragm to be punctured after the battery cell is manufactured, causing safety hazards.
[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0006] The composite current collector comprises an insulating base layer and a metal layer. Along the length direction of the insulating base layer, the insulating base layer has a first region and a second region connected to each other. The metal layer is arranged on at least one surface of the first region, and the second region is used to be arranged corresponding to the cutting position of the pole piece.
[0007] Preferably, the thickness of the first region is smaller than the thickness of the second region.
[0008] Preferably, along the thickness direction of the insulating base layer, the surface of the second region is flush with the surface of the metal layer.
[0009] Preferably, two second regions are provided, and the two second regions are connected via the first region.
[0010] Preferably, the two second regions have the same size.
[0011] Preferably, the length of each of the second regions is 0.5-6 mm.
[0012] Another object of the present invention is to provide a battery pole piece, comprising an active material layer and the composite current collector as described above in the specification, wherein the active material layer is arranged on the metal layer.
[0013] Preferably, along the thickness direction of the insulating base layer, the surface of the second region is flush with the surface of the active material layer.
[0014] Another object of the present utility model is to provide a battery, comprising a shell and a battery cell, wherein the battery cell is arranged in the shell, and the battery cell comprises a first pole piece, a second pole piece, and a diaphragm arranged between the first pole piece and the second pole piece, the polarities of the first pole piece and the second pole piece are opposite, and at least one of the first pole piece and the second pole piece is the battery pole piece described in the previous text of the specification.
[0015] Another object of the present invention is to provide an electrical device, comprising the battery described above in the specification.
[0016] The beneficial effect of the utility model lies in that the composite current collector of the utility model, through the coordinated use of the insulating base layer and the metal layer, the first area of the insulating base layer is used to coat the metal layer, and the second area of the insulating base layer is used to correspond to the cutting position of the pole piece. After the second area of the insulating base layer is cut, the battery pole piece feeding position and the tail position formed have no burr risk and do not have conductivity, which can effectively prevent the burrs from piercing the diaphragm and causing the positive and negative electrodes to be conductive, thereby improving the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The features, advantages and technical effects of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.
[0018] Figure 1 It is a schematic diagram of the structure of the composite current collector of the utility model.
[0019] Figure 2 This is another schematic diagram of the structure of the composite current collector of the utility model.
[0020] Figure 3 It is a structural schematic diagram of the battery pole piece of the utility model.
[0021] Figure 4 This is another structural schematic diagram of the battery electrode of the utility model.
[0022] Figure 5 It is a schematic diagram of the partial structure of the battery cell of the utility model.
[0023] The reference numerals are described as follows:
[0024] 100, battery cell; 101, first pole piece; 102, second pole piece; 103, diaphragm;
[0025] 10. Battery pole piece;
[0026] 20. composite current collector; 21. insulating base layer; 211. first region; 212. second region; 22. metal layer;
[0027] 30. Active material layer;
[0028] a. Length direction of the insulating base layer; b. Length of the second region; c. Thickness direction of the insulating base layer. DETAILED DESCRIPTION
[0029] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.
[0030] Furthermore, the terms “first”, “second”, etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.
[0031] In the utility model, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like 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 mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to the specific circumstances.
[0032] The following is combined with Figures 1 to 5 The utility model is further described in detail, but it is not intended to limit the utility model.
[0033] The electrical equipment of the embodiment of the utility model includes a battery. The electrical equipment may be a car, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The car may be a fuel car, a gas car, or a new energy car, and the new energy car may be a pure electric car, a hybrid car, or an extended-range car, and the like; the spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft, and the like; the electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like; the electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, and the like. The embodiment of the present application does not impose any special restrictions on the above-mentioned electrical equipment.
[0034] The battery of the embodiment of the utility model comprises a housing and a battery cell 100 , wherein the battery cell 100 is arranged in the housing. The battery cell 100 comprises a battery pole piece 10 .
[0035] It should be noted that the battery can be one or more. If there are multiple batteries, the multiple batteries can be connected in series, in parallel, or in mixed connection. Mixed connection means that multiple batteries are connected in series and in parallel. Multiple batteries can be directly connected in series, in parallel, or in mixed connection to form a whole; of course, multiple batteries can also be connected in series, in parallel, or in mixed connection to form a battery module, and multiple battery modules can then be connected in series, in parallel, or in mixed connection to form a whole.
[0036] The battery pole piece 10 of the embodiment of the utility model comprises an active material layer 30 and a composite current collector 20 , and the active material layer 30 is disposed on the composite current collector 20 .
[0037] See also Figures 1 to 5 The composite current collector 20 of the embodiment of the utility model includes an insulating base layer 21 and a metal layer 22. Along the length direction a of the insulating base layer 21, the insulating base layer 21 has a first area 211 and a second area 212 that are connected to each other. The metal layer 22 is arranged on at least one surface of the first area 211, and the second area 212 is used to correspond to the cutting position of the pole piece.
[0038] Compared with the prior art, the composite current collector 20 of the embodiment of the utility model is used in conjunction with the insulating base layer 21 and the metal layer 22. The first area 211 of the insulating base layer 21 is used to coat the metal layer 22, and the second area 212 of the insulating base layer 21 is used to correspond to the cutting position of the electrode. After the second area 212 of the insulating base layer 21 is cut, the feeding position and the finishing position of the formed battery electrode 10 have no burr risk and do not have conductivity. This can effectively prevent the burrs from piercing the diaphragm 103 and causing the positive and negative electrodes to be conductive, thereby improving the safety of the battery.
[0039] In some embodiments, the active material layer 30 is disposed on the metal layer 22 to ensure the conductive effect of the battery.
[0040] See also Figure 2 and 4 In some embodiments, the thickness of the first region 211 is less than the thickness of the second region 212. In this way, the insulating base layer 21 can form a space for accommodating the metal layer 22 in the first region 211, and at least part of the metal layer 22 can be accommodated in the space, which effectively improves the bonding strength between the insulating base layer 21 and the metal layer 22, thereby reducing the risk of the metal layer 22 falling off.
[0041] Furthermore, along the thickness direction c of the insulating base layer 21, the surface of the second region 212 is flush with the surface of the metal layer 22. The entire metal layer 22 can be accommodated in the space, effectively improving the bonding strength between the insulating base layer 21 and the metal layer 22, thereby reducing the risk of the metal layer 22 falling off. At this time, the surface of the composite current collector 20 is flat, so as to facilitate the coating of the active material layer 30.
[0042] In actual use, the entire metal layer 22 can be accommodated in the space, so that the second area 212 of the insulating base layer 21 can cover the side of the metal layer 22, effectively preventing the metal layer 22 from forming burrs at the electrode feeding position and the finishing position.
[0043] Furthermore, along the thickness direction c of the insulating base layer 21, the surface of the second region 212 is flush with the surface of the active material layer 30. The entire active material layer 30 can be accommodated in the space, effectively improving the bonding strength between the active material layer 30 and the composite current collector 20, thereby reducing the risk of the active material layer 30 falling off. At this time, the surface of the battery pole piece 10 is flat, which is conducive to the electrochemical reaction, thereby reducing the occurrence of lithium precipitation.
[0044] During actual use, the entire active material layer 30 can be accommodated in this space, so that the second area 212 of the insulating base layer 21 can cover the side of the active material layer 30, effectively avoiding the formation of burrs on the side of the active material layer 30, and can better play an insulating role, thereby avoiding the occurrence of short circuits.
[0045] Of course, the active material layer 30 may also have a protrusion protruding from the space, and the protrusion may cover at least a portion of the second area 212 .
[0046] See also Figures 3-4In some embodiments, two second regions 212 are provided, and the two second regions 212 are connected by the first region 211. Through the provision of the two second regions 212, the two second regions 212 are respectively located at the two ends of the first region 211. After cutting, one of the two first regions 211 is the feeding position of the battery electrode 10, and the other of the two first regions 211 is the finishing position of the battery electrode 10.
[0047] Furthermore, the two second regions 212 have the same size, so that the size of the battery electrode sheet 10 feeding position and the size of the battery electrode sheet 10 finishing position are the same, which is convenient for the production and preparation of the battery electrode sheet 10 .
[0048] In some embodiments, the length b of each second region 212 is 0.5-6 mm. The second regions 212 in this length range can minimize residual materials, thereby reducing production costs and waste.
[0049] Specifically, the length b of each second region 212 is 0.5-2 mm, 2-4 mm or 4-6 mm. Preferably, the length b of each second region 212 is 2-4 mm. For example, the length b of each second region 212 is 2 mm, 2.4 mm, 2.8 mm, 3 mm, 3.5 mm, 3.8 mm or 4 mm, but is not limited to the listed values, and other values within the numerical range are also applicable.
[0050] In some embodiments, the thickness of the insulating base layer 21 is 2-15 μm. The insulating base layer 21 within this thickness range can effectively ensure the insulating performance of the insulating base layer 21 while avoiding increasing the overall thickness of the composite current collector 20 to increase the thickness of the battery cell 100, thereby affecting the capacity of the battery.
[0051] Preferably, the thickness of the insulating base layer 21 is 4-10 μm. For example, the thickness of the insulating base layer 21 is 4 μm, 4.2 μm, 5 μm, 5.8 μm, 6 μm, 6.4 μm, 7 μm, 7.5 μm, 8 μm, 9 μm or 10 μm, but is not limited to the listed values, and other values within the numerical range are also applicable.
[0052] It should be noted that the insulating base layer 21 is one of polyethylene, polypropylene, polyethylene terephthalate and polyimide.
[0053] In some embodiments, the thickness of the metal layer 22 is 0.5-5 μm. The metal layer 22 within this thickness range can effectively ensure the conductivity of the metal layer 22 while avoiding increasing the overall thickness of the composite current collector 20 to increase the thickness of the battery cell 100, thereby affecting the capacity of the battery.
[0054] Specifically, the thickness of the metal layer 22 is 0.5-1 μm, 1-2 μm, 2-3 μm, 3-4 μm or 4-5 μm. Preferably, the thickness of the metal layer 22 is 1-2 μm. For example, the thickness of the metal layer 22 is 1 μm, 1.2 μm, 1.5 μm, 1.8 μm, 1.9 μm or 2 μm, but is not limited to the listed values, and other values within the numerical range are also applicable.
[0055] It should be noted that the metal layer 22 is aluminum or copper.
[0056] In some embodiments, in order to ensure that the metal layers 22 on both sides of the insulating base layer 21 can be conductive and improve the conductivity of the battery electrode 10, multiple through holes can be set on the first area 211, and the through holes are filled with conductive materials, or the metal layer 22 is partially filled in the through holes.
[0057] See also Figure 5 The battery cell 100 of the embodiment of the utility model comprises a first pole piece 101, a second pole piece 102 and a diaphragm 103 disposed between the first pole piece 101 and the second pole piece 102. The polarities of the first pole piece 101 and the second pole piece 102 are opposite. At least one of the first pole piece 101 and the second pole piece 102 is the battery pole piece 10 of the above embodiment.
[0058] Specifically, the battery cell 100 may be a wound battery cell 100 or a laminated battery cell 100 .
[0059] It should be noted that one of the first pole piece 101 and the second pole piece 102 is a positive pole piece, and the other of the first pole piece 101 and the second pole piece 102 is a negative pole piece.
[0060] According to the disclosure and teaching of the above description, the technicians in the field of the utility model can also change and modify the above implementation. Therefore, the utility model is not limited to the above specific implementation, and any obvious improvement, replacement or modification made by the technicians in this field on the basis of the utility model belongs to the protection scope of the utility model. In addition, although some specific terms are used in this specification, these terms are only for the convenience of explanation and do not constitute any limitation to the utility model.
Claims
1. A composite current collector, characterized in that: The invention comprises an insulating base layer (21) and a metal layer (22); along the length direction (a) of the insulating base layer (21), the insulating base layer (21) has a first region (211) and a second region (212) which are connected to each other; the metal layer (22) is arranged on at least one surface of the first region (211); and the second region (212) is used to be arranged corresponding to the cutting position of the pole piece.
2. The composite current collector according to claim 1, characterized in that: The thickness of the first region (211) is smaller than the thickness of the second region (212).
3. The composite current collector according to claim 2, characterized in that: Along the thickness direction (c) of the insulating base layer (21), the surface of the second region (212) is flush with the surface of the metal layer (22).
4. The composite current collector according to claim 1, characterized in that: Two second regions (212) are provided, and the two second regions (212) are connected via the first region (211).
5. The composite current collector according to claim 4, characterized in that: The two second regions (212) have the same size.
6. The composite current collector according to claim 4 or 5, characterized in that: The length (b) of each of the second regions (212) is 0.5 to 6 mm.
7. Battery pole piece, characterized in that: It comprises an active material layer (30) and the composite current collector according to any one of claims 1 to 6, wherein the active material layer (30) is arranged on the metal layer (22).
8. The battery pole piece according to claim 7, characterized in that: Along the thickness direction (c) of the insulating base layer (21), the surface of the second region (212) is flush with the surface of the active material layer (30).
9. A battery, characterized in that: The invention comprises a shell and a battery cell (100), wherein the battery cell (100) is arranged in the shell, and the battery cell (100) comprises a first pole piece (101), a second pole piece (102), and a diaphragm (103) arranged between the first pole piece (101) and the second pole piece (102), wherein the polarities of the first pole piece (101) and the second pole piece (102) are opposite, and at least one of the first pole piece (101) and the second pole piece (102) is the battery pole piece according to claim 7 or 8.
10. Electrical equipment, characterized in that: A battery comprising the battery of claim 9.