Current collector, electrode sheet, electrode core, battery and preparation method therefor, and electrical device

Abstract

An electrical device (1000), comprising a battery (400). The battery (400) comprises an electrode sheet (200) or an electrode core (300). The electrode core (300) comprises the electrode sheet (200). The electrode sheet (200) comprises a current collector (100). The current collector (100) comprises a support layer (1), a first conductive layer (2), and a second conductive layer (3). The support layer (1) comprises a main body and a conductive material. The support layer (1) is obtained by mixing and forming the main body and the conductive material. The resistance of the support layer (1) is R1, where R1 satisfies: 1 Ω ≤ R1 ≤ 1000 GΩ.

Description

Current collector, electrode, electrode core, battery, its preparation method and electrical equipment

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411218794.9, filed on August 30, 2024, with the China National Intellectual Property Administration, entitled "Current collector, electrode sheet, electrode core, battery and method of preparation thereof and electrical equipment thereof", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of battery technology, and in particular to a current collector, electrode, electrode core, battery, method of preparation thereof, and electrical equipment thereof. Background Technology

[0004] In related technologies, composite current collectors include an insulating layer and a conductive layer. The insulating layer can reduce the weight of the composite current collector. After the composite current collector is coated and rolled, a pure metal structural component needs to be welded separately to the end of the composite current collector to serve as the electrode tab, which facilitates the connection between the electrode tab and the battery cover plate. This process is complex, slightly increases the cost, and has a low welding yield.

[0005] Public content

[0006] This disclosure aims to at least address one of the technical problems existing in the prior art. To this end, one object of this disclosure is to provide a current collector that, by adding a conductive material to a support layer, makes the support layer conductive, eliminating the need to weld tabs onto the current collector; the end of the current collector can be used as a tab; the process is simple and the cost is low.

[0007] The second objective of this disclosure is to provide an electrode employing the aforementioned current collector.

[0008] The third objective of this disclosure is to propose an electrode core employing the aforementioned electrode sheet.

[0009] The fourth objective of this disclosure is to provide a battery employing the aforementioned electrode sheet or electrode core.

[0010] The fifth objective of this disclosure is to provide a method for preparing a battery.

[0011] The sixth object of this disclosure is to provide an electrical device that uses the aforementioned battery.

[0012] A current collector according to a first aspect of this disclosure includes: a support layer, the support layer comprising a body and a conductive material, the body and the conductive material being mixed and molded to obtain the support layer, the resistance of the support layer being R1, wherein R1 satisfies: 1Ω≤R1≤1000GΩ.

[0013] According to the embodiments of the present disclosure, the current collector, by adding conductive material to the support layer, makes the entire support layer conductive. When the current collector is used in a battery, the ends of the current collector protruding from the first and second active layers can serve as tabs for direct resistance welding to the battery cover. This results in good welding performance, eliminating the need for a separate tab welding process on the current collector, simplifying the battery manufacturing process and reducing costs. Furthermore, the improved conductivity of the current collector facilitates the resistance welding of the tab portion to the battery cover, resulting in shorter welding time, better welding performance, higher welding yield, and greater process feasibility. Additionally, the support layer includes a main body, which is lightweight, thereby reducing the mass of the current collector and increasing energy density. Moreover, by ensuring that R1 satisfies 1Ω≤R1≤1000GΩ, welding operations are facilitated, and the connection effect is good.

[0014] According to some embodiments of this disclosure, R1 satisfies: 100Ω≤R1≤800MΩ.

[0015] According to some embodiments of this disclosure, the conductive material accounts for a mass percentage m of the body, wherein m satisfies: 15% ≤ m ≤ 20%.

[0016] According to some embodiments of this disclosure, the conductive material is at least one of carbon black, carbon fiber, and carbon nanotubes.

[0017] According to some embodiments of this disclosure, the resistance of the conductive material is R2, wherein R2 satisfies: 1000Ω≤R2≤20000Ω.

[0018] According to some embodiments of this disclosure, the thickness of the support layer is W1, wherein W1 satisfies: 1.5um ≤ W1 ≤ 10um.

[0019] According to some embodiments of this disclosure, W1 further satisfies: 3um ≤ W1 ≤ 5um.

[0020] According to some embodiments of this disclosure, the material of the main body is a polymer material.

[0021] According to some embodiments of this disclosure, the main body is made of polyethylene terephthalate and / or polypropylene.

[0022] According to some embodiments of this disclosure, the current collector further includes: a first conductive layer; and a second conductive layer, wherein the first conductive layer and the second conductive layer are respectively disposed on both sides of the support layer in the thickness direction.

[0023] According to some embodiments of this disclosure, the thicknesses of the first conductive layer and the second conductive layer are W2, wherein W2 satisfies: 0.1um ≤ W2 ≤ 13um.

[0024] According to some embodiments of this disclosure, W2 further satisfies: 0.8um ≤ W2 ≤ 6um.

[0025] According to some embodiments of this disclosure, the first conductive layer and the second conductive layer are made of copper or aluminum.

[0026] The electrode according to a second aspect embodiment of the present disclosure includes the current collector described in the first aspect embodiment above.

[0027] According to some embodiments of this disclosure, the electrode further includes: a first active layer; and a second active layer, the first active layer and the second active layer being respectively disposed on both sides of the current collector in the thickness direction; at least one edge of the current collector along a first direction protrudes from the corresponding edge of the first active layer and the second active layer along the first direction to form an electrode tab, the first direction and the thickness direction being perpendicular to each other.

[0028] The electrode core according to a third aspect embodiment of the present disclosure includes at least two electrode sheets, the electrode sheets being those described in the second aspect embodiment above, and the two electrode sheets having opposite polarities.

[0029] According to some embodiments of this disclosure, two electrode sheets are stacked to form the electrode core; or, two electrode sheets are stacked and then wound to form the electrode core.

[0030] A battery according to a fourth aspect of this disclosure includes an electrode sheet as described in the second aspect of the above-described embodiment, or includes an electrode core as described in the third aspect of the above-described embodiment.

[0031] According to some embodiments of this disclosure, the tabs of the electrode are resistively welded to the cover plate of the battery.

[0032] A method for preparing a battery according to a fifth aspect embodiment of the present disclosure includes the following steps:

[0033] A first active layer and a second active layer are coated on both sides of the current collector in the thickness direction to obtain the electrode sheet according to the second aspect embodiment described above, wherein the current collector is the current collector according to the first aspect embodiment described above.

[0034] According to some embodiments of this disclosure, the method for preparing the battery further includes: resistively welding the tabs of the electrode sheet to the cover plate of the battery.

[0035] The electrical device according to the sixth aspect of the present disclosure includes a battery using the battery described in the fourth aspect of the present disclosure, or a battery prepared according to the battery preparation method described in the fifth aspect of the present disclosure.

[0036] Additional aspects and advantages of this disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure. Attached Figure Description

[0037] The above and / or additional aspects and advantages of this disclosure will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0038] Figure 1 is a schematic diagram of a current collector according to an embodiment of the present disclosure;

[0039] Figure 2 is a schematic diagram of an electrode sheet according to an embodiment of the present disclosure;

[0040] Figure 3 is a side view of an electrode core according to an embodiment of the present disclosure, wherein multiple electrode sheets are stacked.

[0041] Figure 4 is a top view of a battery according to an embodiment of the present disclosure;

[0042] Figure 5 is a schematic diagram of the welding of the cover plate and the tab of the battery according to the present disclosure;

[0043] Figure 6 is a schematic diagram of a battery cover according to an embodiment of the present disclosure;

[0044] Figure 7 is a schematic block diagram of an electrical appliance according to an embodiment of the present disclosure.

[0045] Reference numerals: 1000, electrical equipment; 100, current collector; 200, electrode sheet; 300, electrode core; 400, battery; 1, support layer; 2, first conductive layer; 3, second conductive layer; 4, first active layer; 5, second active layer; 6, tab; 7, cover plate. Detailed Implementation

[0046] The embodiments of this disclosure are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The current collector 100 according to a first aspect embodiment of this disclosure is described below with reference to FIG1.

[0047] As shown in FIG1, the current collector 100 according to the first aspect of the present disclosure includes a support layer 1, a first conductive layer 2, and a second conductive layer 3.

[0048] Specifically, the support layer 1 comprises a main body and a conductive material. The main body and the conductive material are mixed and molded to obtain the support layer 1. The resistance of the support layer 1 is R1, where R1 satisfies: 1Ω ≤ R1 ≤ 1000GΩ. The first conductive layer 2 and the second conductive layer 3 are respectively disposed on both sides of the support layer 1 in the thickness direction. It should be noted that the resistance value of the support layer 1 is the result measured on the current collector 100 using an ohmmeter. When a metal layer, such as the first conductive layer 2 and the second conductive layer 3, is present on the current collector 100, the resistance of the metal layer is very small and can be ignored compared to the resistance of the support layer 1. Therefore, the measured resistance of the current collector 100 is the resistance of the support layer 1.

[0049] For example, in the example of Figure 1, along the thickness direction of the support layer 1 (i.e., the left-right direction in Figure 1), there are sequentially a first conductive layer 2, a support layer 1, and a second conductive layer 3. The first conductive layer 2 and the second conductive layer 3 are respectively coated on both sides of the support layer 1 along the thickness direction. Along the first direction (i.e., the up-down direction in Figure 1), the first conductive layer 2, the second conductive layer 3, and the support layer 1 have the same length. The support layer 1 is formed by mixing and molding the main body and conductive material.

[0050] Therefore, by adding conductive material to the main body, the main body also becomes conductive, and the conductivity of the support layer 1 is improved, making it easier for a portion of the support layer 1 to be used as a tab. Compared with conventional technology, which uses pure metal materials as tabs, the resistance is low, making resistance welding impossible, and the connection effect is unstable and poor. In this application, no conductive material is added to the support layer 1, and the main body is usually made of polymer materials. Polymer materials are lightweight, and most have poor conductivity and high resistance, which is also not conducive to resistance welding. By adding conductive material to the main body, the support layer 1 of this application becomes conductive as a whole, and the resistance of the support layer 1 is kept within a specified range, making it easier for a portion of the support layer 1 to be used as a tab 6, thus meeting the performance requirements of the tab 6.

[0051] When the current collector 100 is used in the battery 400, a first active layer 4 and a second active layer 5 are coated on the sides of the first conductive layer 2 and the second conductive layer 3 that are far apart from each other. The length of the first active layer 4 and the second active layer 5 along the first direction is less than the length of the current collector 100. That is, the protruding ends of the current collector 100 from the first active layer 4 and the second active layer 5 can be used as tabs 6 for direct resistance welding to the cover plate 7 of the battery 400. The welding performance is good, it is not easy to generate foreign matter such as welding slag, the welding effect is good, and the connection is firm. This eliminates the need for the process of welding tabs 6 separately to the current collector 100, making the manufacturing process of the battery 400 simple and the cost lower. In addition, using a portion of the current collector 100 as tabs 6 makes tabs 6 less prone to tearing and falling off, which is beneficial for the long-term stable use of tabs 6.

[0052] Furthermore, when the resistance of the support layer 1 is less than 1Ω, the welding power of the tab 6 and the cover plate 6 during resistance welding is high, and the welding time is long. Prolonged welding leads to extended heating time, which can easily damage the current collector 100 and reduce the connection effect. When the resistance of the support layer 1 is greater than 1000GΩ, current cannot pass through the current collector 100, resulting in high heat generation during resistance welding and low welding yield. Therefore, by setting the resistance R1 of the support layer 1 to satisfy: 1Ω≤R1≤1000GΩ, the conductivity of the current collector 100 is improved. This facilitates the resistance welding of the part of the current collector 100 acting as the tab 6 to the cover plate 7 of the battery 400, resulting in shorter welding time, better welding performance, higher welding yield, and higher process feasibility. Additionally, the support layer 1 includes a main body, which is lightweight, thereby reducing the mass of the current collector 100 and increasing energy density. That is, by controlling the resistance value of the support layer 1, the end part of the current collector 100 can act as the electrode 6, without the need to set the electrode 6 separately. At the same time, the electrode 6 can be connected to the cover plate 7 by resistance welding, which has good stability, good connection effect, and can meet the performance requirements.

[0053] According to the embodiments of the present disclosure, the current collector 100, by adding conductive material to the support layer 1, makes the support layer 1 as a whole conductive. When the current collector 100 is used in the battery 400, the ends of the current collector 100 protruding from the first active layer 4 and the second active layer 5 can be used as tabs 6 for direct resistance welding to the cover plate 7 of the battery 400. The welding performance is good, thus eliminating the need for a separate process of welding the tabs 6 onto the current collector 100, simplifying the manufacturing process of the battery 400 and reducing costs. In addition, the improved conductivity of the current collector 100 facilitates the resistance welding of the portion of the current collector 100 that serves as the tab 6 to the cover plate 7 of the battery 400, resulting in short welding time, good welding performance, high welding yield, and high process feasibility. Furthermore, the support layer 1 includes a main body (e.g., insulating material), which is lightweight, thereby reducing the weight of the current collector 100 and increasing the energy density.

[0054] According to some embodiments of this disclosure, R1 further satisfies: 100Ω≤R1≤800MΩ. Therefore, when R1 further satisfies 100Ω≤R1≤800MΩ, it is more conducive to the welding of the tab 6 to the cover plate 7 of the battery 400, resulting in better welding performance and improved welding yield, thereby enhancing the performance of the current collector 100. For example, it is recommended that the resistance of the electrode core 300 with a thickness of 20mm or less be less than 230MΩ. It should be noted that the above "230MΩ" refers to the resistance value of the corresponding positive or negative tab on the current collector 100 of the entire electrode core 300. For resistance measurement, an ohmmeter is typically used. The ohmmeter can be directly connected to a portion of the tab 6 on the current collector 100 for direct measurement, or multiple electrode sheets 200 can be connected together to form the electrode core 300, and the ohmmeter can be directly connected to the corresponding positive or negative tab for measurement. For resistance welding, excellent connection performance between the tab 6 and the cover plate 7 can be achieved by controlling the resistance of the support layer 1 of the current collector 100. When the electrode core 300 has multiple positive or negative tabs, the aforementioned "230MΩ" refers to the resistance value of a single positive or negative tab. The aforementioned R1 value can be adjusted according to the capacity or thickness specifications of the battery cell to achieve better performance.

[0055] According to some embodiments of this disclosure, the conductive material accounts for a mass percentage m of the main body, where m satisfies: 15% ≤ m ≤ 20%. The resistance value of the support layer 1 can be controlled in various ways, including by controlling the amount of conductive material added to the main body to ensure the resistance value of the support layer 1 meets the usage requirements. Therefore, by setting the mass percentage of the conductive material in the main body to be between 15% and 20%, the resistance of the support layer 1 can be controlled to meet the requirements, thus eliminating the need to continuously measure the resistance of the mixture obtained by mixing the main body and the conductive material during the addition of the conductive material. This simplifies the control method and makes the preparation of the support layer 1 relatively simple. For example, it has been verified that when the mass percentage of the conductive material in the main body is 20%, the measured resistance of the support layer 1 is 232.2 MΩ.

[0056] According to some optional embodiments of this disclosure, the conductive material is at least one of carbon black, carbon fiber, and carbon nanotubes. When the conductive material is at least one of carbon black, carbon fiber, and carbon nanotubes, carbon black, carbon fiber, and carbon nanotubes are carbon-based conductive agents. Their surface functional groups, such as hydroxyl groups, have better bonding with the polymer matrix and can also ensure the toughness of the support layer 1, preventing strip breakage during electrode coating and extending the service life of the electrode 200. Carbon black, carbon fiber, and carbon nanotubes have good conductivity and are lightweight, thus making the support layer 1 relatively lightweight. In other words, the support layer 1, while being lightweight, also has certain conductivity to facilitate the welding of the tab 6. Furthermore, carbon black, carbon fiber, and carbon nanotubes are readily available and have low cost, which can reduce the manufacturing cost of the current collector 100 and improve cycle life. Of course, the conductive material can also be a lightweight metal powder, such as copper powder, but is not limited to this.

[0057] According to some embodiments of this disclosure, the resistance of the conductive material is R2, wherein R2 satisfies: 1000Ω≤R2≤20000Ω. Therefore, by using a conductive material with a resistance of 1000Ω to 20000Ω, the resistance of the resulting support layer 1 can meet the requirements of resistance welding, while also resulting in good welding performance.

[0058] According to some embodiments of this disclosure, the thickness of the support layer 1 is W1, where W1 satisfies: 1.5µm ≤ W1 ≤ 10µm. For example, when the thickness of the support layer 1 is less than 1.5µm, the thickness of the support layer 1 is small, resulting in weak support for the first conductive layer 2 and the second conductive layer 3 coated on both sides of the thickness direction of the support layer 1, increasing the difficulty of fabricating the current collector 100 and reducing the yield. When the thickness of the support layer 1 is greater than 10µm, the thickness of the support layer 1 is too large, thereby increasing the thickness of the current collector 100 and increasing the space occupied by the current collector 100 in the battery 400, which is not conducive to improving the volumetric energy density of the battery 400. Therefore, by setting the thickness W1 of the support layer 1 to satisfy: 1.5µm ≤ W1 ≤ 10µm, the thickness of the support layer 1 is reasonable, which is beneficial to the fabrication of the current collector 100 while also reducing the space occupied by the current collector 100 in the battery 400.

[0059] Furthermore, W1 satisfies: 3um ≤ W1 ≤ 5um. Therefore, when the thickness W1 of the support layer 1 satisfies 3um ≤ W1 ≤ 5um, the thickness of the support layer 1 is smaller. While meeting the usage requirements of the current collector 100, it can save materials, reduce costs, and also reduce the space occupied in the battery 400, thereby increasing the volumetric energy density of the battery 400.

[0060] According to some embodiments of this disclosure, the main body is made of a polymer material, such as a polymer material.

[0061] Furthermore, the main body is made of polyethylene terephthalate (PET) and / or polypropylene (PP). When PET and / or PP are used for the main body, the cost of use is low, the material is readily available, and the weight is small, which can reduce the weight of the current collector 100, thereby increasing the energy density. Of course, other lightweight materials can also be used for the main body.

[0062] According to some embodiments of this disclosure, the thicknesses of the first conductive layer 2 and the second conductive layer 3 are W2, where W2 satisfies: 0.1µm ≤ W2 ≤ 13µm. For example, the thicknesses of the first conductive layer 2 and the second conductive layer 3 are the same. Taking the first conductive layer 2 as an example, when the thickness of the first conductive layer 2 is less than 0.1µm, the thickness of the first conductive layer 2 is too small, making it difficult to coat the first conductive layer 2 evenly on the surface of the support layer 1, thereby reducing the performance of the current collector 100 and reducing processing efficiency. When the thickness of the first conductive layer 2 is greater than 13µm, the material usage of the first conductive layer 2 increases, increasing the cost, and also increasing the thickness of the current collector 100, increasing the impedance. Therefore, considering impedance, process technology, and thickness, setting W2 to satisfy 0.1µm ≤ W2 ≤ 13µm results in a reasonable thickness setting for the first conductive layer 2 and the second conductive layer 3, lower impedance, and simpler manufacturing.

[0063] According to some embodiments of this disclosure, W2 further satisfies: 0.8um ≤ W2 ≤ 6um. Therefore, the thickness settings of the first conductive layer 2 and the second conductive layer 3 within the above range are more reasonable, reducing the overall thickness of the current collector 100 while lowering the impedance and improving the performance of the current collector 100.

[0064] According to some embodiments of this disclosure, the first conductive layer 2 and the second conductive layer 3 are each independently made of copper or aluminum. For example, when the electrode 200 formed by the current collector 100 is a positive electrode, the materials of the first conductive layer 2 and the second conductive layer 3 are preferably aluminum. When the electrode 200 formed by the current collector 100 is a negative electrode, the materials of the first conductive layer 2 and the second conductive layer 3 are preferably copper. When the electrode 200 formed by the current collector 100 is a bipolar electrode, the materials of the first conductive layer 2 and the second conductive layer 3 are preferably copper and aluminum, respectively. Therefore, the first conductive layer 2 and the second conductive layer 3 have better conductivity and lower cost, thereby reducing the production cost of the current collector 100. Of course, other metal materials can also be used for the first conductive layer 2 and the second conductive layer 3.

[0065] The electrode 200 according to a second aspect embodiment of the present disclosure, in conjunction with FIG2, includes the current collector 100 according to the first aspect embodiment described above.

[0066] According to the embodiments of the present disclosure, the electrode 200, by adopting the current collector 100 described above, has a simple manufacturing process, low processing cost, no need to separately weld the electrode tab 6, reduced processing difficulty, high processing efficiency, and high process feasibility.

[0067] According to some embodiments of this disclosure, and referring to FIG2, the electrode 200 further includes a first active layer 4 and a second active layer 5. The first active layer 4 and the second active layer 5 are respectively disposed on both sides of the current collector 100 in the thickness direction. At least one edge of the current collector 100 along a first direction protrudes from the corresponding edge of the first active layer 4 and the second active layer 5 along the first direction to form an electrode tab 6. The first direction and the thickness direction are perpendicular to each other. The active materials in the first active layer 4 and the second active layer 5 may be the same or different, and this solution is not limited thereto.

[0068] For example, the upper edge of the current collector 100 protrudes beyond the upper edges of the first active layer 4 and the second active layer 5, or the lower edge of the current collector 100 protrudes beyond the lower edges of the first active layer 4 and the second active layer 5. The portion of the current collector 100 protruding beyond the first active layer 4 and the second active layer 5 can serve as a tab 6. When the electrode 200 is used in the battery 400, there is no need to weld the tab 6 separately; the aforementioned protruding portion can be directly welded to the cover plate 7, which facilitates the normal use of the battery 400. For example, when the electrode 200 is a positive electrode, the first active layer 4 and the second active layer 5 are positive active materials; when the electrode 200 is a negative electrode, the first active layer 4 and the second active layer 5 are negative active materials. The positive and negative active materials react with the electrolyte, and the tab 6 connects to the cover plate 7 to form a current loop. Moreover, the electrode 200 has a simple structure, low production cost, and improved cycle life.

[0069] According to the third aspect embodiment of this disclosure, the electrode core 300, referring to FIG3, includes at least two electrode sheets 200, which are the same electrode sheets 200 as described in the second aspect embodiment above, and the two electrode sheets 200 have opposite polarities. For example, when two electrode sheets 200 are included, one electrode sheet 200 is a positive electrode sheet, and the other electrode sheet 200 is a negative electrode sheet. When multiple electrode sheets 200 are included, the multiple electrode sheets 200 can be respectively multiple positive electrode sheets and multiple negative electrode sheets, with the positive electrode tabs of the multiple positive electrode sheets facing each other, and the negative electrode tabs of the multiple negative electrode sheets facing each other. Thus, by using the above-described electrode sheets 200, the manufacturing process of the electrode core 300 is simple, the processing cost is low, the processing efficiency is low, and the process feasibility is high.

[0070] Optionally, when multiple electrodes 200 of the same polarity are connected, the corresponding tabs 6 of two adjacent electrodes 200 are connected by welding. The welding width of the tabs 6 between two adjacent electrodes 200 is d1, and the width of the tabs 6 is d2, where d1 and d2 satisfy: d1+2mm≤d2≤d1+12mm. For example, when the welding width is set to d1 according to welding requirements and the performance of the electrode core 300, the width of the tabs 6 on both sides of the welding position is at least 1mm and at most 6mm. Thus, the size of the tabs 6 is reasonably set, which not only meets the usage requirements of the tabs 6, but also helps to ensure the stability of resistance welding and the rate of the battery 400. It should be noted that the width of the tabs 6 mentioned above refers to the width of the tabs 6 in the left-right direction in Figure 3.

[0071] According to some embodiments of this disclosure, two electrode sheets 200 are stacked to form an electrode core 300. Alternatively, two electrode sheets 200 are stacked and then wound to form the electrode core 300. For example, when the battery 400 is a square battery 400, the positive electrode sheet and the negative electrode sheet are stacked to form the electrode core 300. When the battery 400 is a cylindrical battery 400, the positive electrode sheet and the negative electrode sheet are stacked with an insulating film between them, and then wound into a cylindrical shape to form a cylindrical electrode core 300. Therefore, the electrode core 300 is easy to process and highly efficient.

[0072] A battery 400 according to a fourth aspect embodiment of the present disclosure, referring to FIG4, includes an electrode 200 according to the second aspect embodiment described above, or includes an electrode core 300 according to the third aspect embodiment described above.

[0073] According to the embodiments of the present disclosure, the battery 400, by employing the aforementioned electrode sheet 200 or electrode core 300, has a simple processing technology, low difficulty, and fewer steps, thereby improving the processing efficiency of the battery 400. Furthermore, the tabs 6 are less prone to tearing and falling off, which is beneficial for the long-term use of the tabs 6, thus extending the service life and stability of the battery 400.

[0074] According to some embodiments of this disclosure, the tab 6 of the electrode 200 is resistively welded to the cover plate 7 of the battery 400. Therefore, by using resistance welding, fewer foreign objects are generated, welding slag is less likely to form, power consumption is lower, and the connection effect is better, improving the connection stability between the tab 6 and the cover plate 7. In contrast, ultrasonic welding is difficult to detect, and laser welding is prone to producing welding slag.

[0075] The method for preparing a battery according to the fifth aspect of this disclosure, in conjunction with Figures 4-6, includes the following steps:

[0076] S1. Add conductive material to the main body to obtain a mixed material, and after molding, obtain a support layer;

[0077] S2. A first conductive layer and a second conductive layer are coated on both sides of the support layer in the thickness direction to obtain a current collector according to the first aspect embodiment described above.

[0078] For example, during the preparation of the support layer 1, conductive materials are added to give the support layer 1 certain conductivity, while ensuring that the resistance R1 of the support layer 1 satisfies 1Ω≤R1≤1000GΩ. The mixed material is then molded to obtain the support layer 1. Then, a first conductive layer 2 and a second conductive layer 3 are coated onto the support layer 1 to obtain the current collector 100. Therefore, the current collector 100 has a simple structure, a simple preparation method, and is easy to process. Moreover, the support layer 1 of the processed current collector 100 also has conductivity, and the two ends of the current collector 100 along the vertical direction can be used as tabs 6, simplifying the manufacturing process of the battery 400 and making it more advantageous for the production and processing of the battery 400.

[0079] According to some embodiments of this disclosure, adding a conductive material to the body includes:

[0080] S11. Add conductive material to the main body at a mass ratio of 15% to 20%.

[0081] S12. While adding conductive material to the main body, measure the resistance of the mixed material. Stop adding when the resistance of the mixed material is less than 1000 GΩ.

[0082] In other words, the resistance of the mixed material with added conductive material can meet the requirements through the two methods described above. First, control the amount of conductive material added; this method is simple to operate and simplifies the fabrication of battery 400. Second, continuously measure the resistance of the mixed material during the addition of conductive material, and stop adding conductive material once the resistance meets the requirements. By setting different control methods, the fabrication of battery 400 can be diversified, and the resistance of the support layer can be controlled according to practical convenience, which is more conducive to the fabrication of battery 400.

[0083] According to some embodiments of this disclosure, the method for preparing the battery further includes:

[0084] S3. A first active layer and a second active layer are coated on both sides of the current collector in the thickness direction to obtain an electrode according to the second aspect embodiment described above.

[0085] For example, the first active layer 4 and the second active layer 5 are made of the same material and have the same thickness. The electrode 200 is simplified by coating the current collector 100 with an active material to obtain the first active layer 4 and the second active layer 5. Furthermore, there is no need to weld tabs 6 onto the current collector 100; the portions protruding from the first active layer 4 and the second active layer 5 can be used as tabs 6, making the fabrication of the battery 400 even simpler.

[0086] According to some embodiments of this disclosure, the method for preparing the battery further includes:

[0087] S4. Take two electrodes with opposite polarities and stack them or stack them and then wind them to obtain the electrode core according to the third aspect embodiment described above.

[0088] Of course, multiple electrode sheets 200 can also be set, including multiple positive electrode sheets and multiple negative electrode sheets. Depending on the needs of the battery 400, the electrode sheets 200 can be stacked or stacked and then wound into a cylindrical electrode core 300. The processing method of the electrode core 300 is simple and low difficulty.

[0089] According to some embodiments of this disclosure, the battery manufacturing method further includes resistance welding of the tabs of the electrode sheets to the cover plate of the battery. For example, the battery 400 includes a casing (not shown) and a cover plate 7, with the electrode core 300 disposed inside the casing. The cover plate 7 is fitted onto the casing to obtain the battery 400, and the casing can support and protect the electrode core. The cover plate 7 includes a cover plate 7, and the tabs 6 and the cover plate 7 are resistance welded to form an electrical circuit. The tabs 6 and the cover plate 7 have good welding performance, a strong connection, and low impedance. In addition, the manufacturing process of the battery 400 reduces the welding process of the tabs 6, improves the process yield, and further reduces the production cost.

[0090] The electrical device 1000 according to the sixth aspect embodiment of this disclosure includes the battery 400 according to the fourth aspect embodiment above, or the battery prepared by the method of the fifth aspect embodiment above, as shown in FIG7.

[0091] According to the embodiments of the present disclosure, the electrical equipment 1000 improves the performance of a vehicle by employing the battery 400 described above. For example, the electrical equipment 1000 includes vehicles, aircraft, ships, computers, energy storage cabinets, etc.

[0092] Other configurations and operations of the electrode core 300, battery 400, and electrical device 1000 according to embodiments of this disclosure are known to those skilled in the art and will not be described in detail here.

[0093] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0094] In the description of this disclosure, "multiple" means two or more.

[0095] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0096] Although embodiments of this disclosure have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. A current collector (100), characterized in that, include: The support layer (1) includes a main body and a conductive material. The main body and the conductive material are mixed and molded to obtain the support layer (1). The resistance of the support layer (1) is R1, wherein R1 satisfies: 1Ω≤R1≤1000GΩ.

2. The current collector (100) according to claim 1, characterized in that, The condition R1 satisfies: 100Ω≤R1≤800MΩ.

3. The current collector (100) according to claim 1 or 2, characterized in that, The conductive material accounts for m% of the mass of the main body, wherein m satisfies: 15% ≤ m ≤ 20%.

4. The current collector (100) according to any one of claims 1-3, characterized in that, The conductive material is at least one of carbon black, carbon fiber, and carbon nanotubes.

5. The current collector (100) according to any one of claims 1-4, characterized in that, The resistance of the conductive material is R2, wherein R2 satisfies: 1000Ω≤R2≤20000Ω.

6. The current collector (100) according to any one of claims 1-5, characterized in that, The thickness of the support layer (1) is W1, wherein W1 satisfies: 1.5um≤W1≤10um.

7. The current collector (100) according to claim 6, characterized in that, The W1 further satisfies: 3um≤W1≤5um.

8. The current collector (100) according to any one of claims 1-7, characterized in that, The main body is made of polymer material.

9. The current collector (100) according to claim 8, characterized in that, The main body is made of polyethylene terephthalate and / or polypropylene.

10. The current collector (100) according to any one of claims 1-9, characterized in that, Further includes: First conductive layer (2); and The second conductive layer (3) is provided on both sides of the support layer (1) in the thickness direction, with the first conductive layer (2) and the second conductive layer (3) respectively.

11. The current collector (100) according to claim 10, characterized in that, The thicknesses of the first conductive layer (2) and the second conductive layer (3) are W2, wherein W2 satisfies: 0.1um≤W2≤13um.

12. The current collector (100) according to claim 11, characterized in that, The W2 further satisfies: 0.8um≤W2≤6um.

13. The current collector (100) according to any one of claims 10-12, characterized in that, The first conductive layer (2) and the second conductive layer (3) are made of copper or aluminum.

14. An electrode (200), characterized in that, Includes the current collector (100) according to any one of claims 1-13.

15. The electrode (200) according to claim 14, characterized in that, Also includes: First active layer (4); and The second active layer (5) is provided on both sides of the current collector (100) in the thickness direction, and the first active layer (4) and the second active layer (5) are respectively provided on both sides of the current collector (100) in the thickness direction. At least one edge of the current collector (100) protrudes from the corresponding edge of the first active layer (4) and the second active layer (5) in the first direction to form a tab (6). The first direction and the thickness direction are perpendicular to each other.

16. An electrode core (300), characterized in that, It includes at least two electrodes (200), said electrodes (200) being the electrodes (200) according to claim 14 or 15, said electrodes (200) having opposite polarities.

17. The electrode core (300) according to claim 16, characterized in that, Two of the electrode plates (200) are stacked to form the electrode core (300); or The two electrode sheets (200) are stacked and then wound to form the electrode core (300).

18. A battery (400), characterized in that, Includes the electrode sheet (200) according to claim 14 or 15, or includes the electrode core (300) according to claim 16 or 17.

19. The battery (400) according to claim 18, characterized in that, The tabs (6) of the electrode (200) are resistively welded to the cover plate (7) of the battery (400).

20. A method for preparing a battery, characterized in that, Includes the following steps: A first active layer and a second active layer are coated on both sides of the current collector in the thickness direction to obtain the electrode according to claim 14 or 15, wherein the current collector is the current collector according to any one of claims 1-13.

21. The method for preparing a battery according to claim 20, characterized in that, Also includes: The tabs of the electrode are resistively welded to the cover plate of the battery.

22. An electrical appliance (1000), characterized in that, This includes the battery (400) according to claim 18 or 19, or the battery prepared by the method according to claim 20 or 21.

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