A battery cell, a battery, and an electrical device.

Abstract

This application relates to a battery cell, a battery, and an electrical device. The battery cell includes: a cover plate; an insulating plate including an insulating plate body and a pressure plate, the pressure plate being disposed on the side of the insulating plate body opposite to the cover plate, and having a positive electrode clamping section and a negative electrode clamping section; an electrode assembly including a cell body and a positive electrode tab and a negative electrode tab connected to the cell body, wherein the thickness of the positive electrode tab is greater than the thickness of the negative electrode tab, the positive electrode tab is located between the positive electrode clamping section of the pressure plate and the insulating plate body, and the negative electrode tab is located between the negative electrode clamping section of the pressure plate and the insulating plate body; wherein the width W1 of the positive electrode clamping section is smaller than the width W2 of the negative electrode clamping section.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery cell, a battery, and an electrical device. Background Technology

[0002] Lithium batteries consist of a core. During production, a positive electrode adapter is used to weld and fix the positive tab of the core to the positive terminal, and a negative electrode adapter is used to weld and fix the negative tab of the core to the negative terminal. Plastic is used to insulate the adapter from the cover plate. To shape and support the positive and negative tabs during core assembly and to prevent defects such as inverted insertion or cracking, a spacer is placed between the tabs and the core.

[0003] Please see Figure 1 When the pad and the lower plastic are fixed, the pad will exert a clamping force on the positive and negative tabs, causing the positive and negative tabs to pull on the electrode sheets of the core. Since the thickness of the positive electrode sheet is generally greater than that of the negative electrode sheet, the ductility and fatigue resistance of the positive electrode sheet are poor, which makes the connection between the positive tab and the positive electrode sheet (i.e., the root of the positive tab) prone to cracking. Utility Model Content

[0004] Therefore, it is necessary to provide a battery cell, battery, and power device that can reduce the risk of cracking at the root of the positive electrode tab in response to the above problems.

[0005] On one hand, this application provides a single battery cell, comprising:

[0006] Cover plate;

[0007] An insulating board includes an insulating board body and a pressure plate, wherein the pressure plate is disposed on the side of the insulating board body opposite to the cover plate, and has a positive electrode pressing section and a negative electrode pressing section;

[0008] An electrode assembly includes a battery cell body and a positive electrode tab and a negative electrode tab connected to the battery cell body. The thickness of the positive electrode tab is greater than the thickness of the negative electrode tab. The positive electrode tab is located between the positive electrode clamping section of the pressure plate and the insulating plate body, and the negative electrode tab is located between the negative electrode clamping section of the pressure plate and the insulating plate body.

[0009] Wherein, the width dimension W1 of the positive electrode pressing section is smaller than the width dimension W2 of the negative electrode pressing section.

[0010] In some embodiments, the positive electrode clamping section and the negative electrode clamping section of the pressure plate are integrally formed; or

[0011] The positive electrode clamping section and the negative electrode clamping section of the pressure plate are separately configured.

[0012] In some embodiments, the width directions of both the positive electrode clamping section and the negative electrode clamping section are parallel to the first direction;

[0013] The distance between one end face of the negative electrode clamping section in the first direction and one end face of the battery cell body in the first direction is L1, and the distance between one end face of the positive electrode clamping section in the first direction and one end face of the battery cell body in the first direction is L2, and L2 > L1.

[0014] In some embodiments, the width dimension W1 of the positive electrode clamping section and the width dimension W2 of the negative electrode clamping section satisfy: 0.1mm ≤ W2 - W1 ≤ 10mm; and / or

[0015] The width W2 of the negative electrode clamping section satisfies: 80% × b ≤ W2 ≤ 100% × b; where b represents the thickness of the cell body; and / or

[0016] The width dimensions W1 of the positive electrode clamping section and W2 of the negative electrode clamping section satisfy: 0mm≤(W2-W1)-Δh≤2mm; where Δh represents the difference between the thickness dimensions of the positive electrode tab and the negative electrode tab.

[0017] In some embodiments, the thickness H1 of the positive electrode clamping section is smaller than the thickness H2 of the negative electrode clamping section.

[0018] In some embodiments, the thickness H1 of the positive electrode clamping section and the thickness H2 of the negative electrode clamping section satisfy: 0.1mm ≤ H2 - H1 ≤ 2mm; and / or

[0019] The thickness H1 of the positive electrode clamping section and the thickness H2 of the negative electrode clamping section satisfy: H2-H1=Δh; where Δh represents the difference between the thickness of the positive electrode tab and the thickness of the negative electrode tab.

[0020] In some embodiments, the thickness H2 of the negative electrode clamping section satisfies: 0.2mm ≤ H2 ≤ 1.5mm.

[0021] In some embodiments, the battery cell body is formed by winding at least a positive electrode sheet, a separator and a negative electrode sheet, the positive electrode tab includes multiple stacked positive electrode tabs, each of the positive electrode tabs being connected to the positive electrode sheet, and the negative electrode tab includes multiple stacked negative electrode tabs, each of the negative electrode tabs being connected to the negative electrode sheet;

[0022] At one end of the cell body facing the negative electrode clamping section, the separator extends beyond the positive electrode and the negative electrode, and the interference between the negative electrode clamping section and the separator is 0 mm to 5 mm.

[0023] On the other hand, this application provides a battery including a battery cell as described in any of the above embodiments.

[0024] In another aspect, this application provides an electrical device including a battery as described in any of the above embodiments.

[0025] Compared with the prior art, this application has the following beneficial effects:

[0026] In the aforementioned battery cells, batteries, and electrical devices, when the positive and negative clamping sections of the pressure plate are fastened to the insulating plate body, the positive clamping section exerts a pulling force on the positive electrode tab, and the negative clamping section exerts a pulling force on the negative electrode tab. Since the width W1 of the positive clamping section is set smaller than the width W2 of the negative clamping section, the width of the positive clamping section is narrowed. This significantly reduces the pulling force exerted by the positive clamping section on the positive electrode tab when the pressure plate is fastened to the insulating plate body, thereby greatly reducing the risk of cracking at the root of the positive electrode tab. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the pad and the electrode tab before core bonding in the prior art;

[0028] Figure 2 This is a schematic diagram of the structure of a single battery cell before it is assembled in one embodiment of this application (the casing is omitted);

[0029] Figure 3 for Figure 2 The front view of the top cover assembly (i.e., cover plate, terminal post and pressure plate) of the battery cell shown;

[0030] Figure 4 for Figure 2 Side view of the top cover assembly of the shown battery cell;

[0031] Figure 5 for Figure 2 The diagram shows the structure of the electrode assembly and positive electrode clamping section of the battery cell after the core is assembled.

[0032] Figure 6 for Figure 2 The diagram shows the structure of the electrode assembly and negative electrode clamping section of the battery cell after the core is assembled.

[0033] Figure 7 This is a schematic diagram of the structure of a single battery cell before it is assembled in another embodiment of this application (the casing is omitted);

[0034] Figure 8 for Figure 7 The front view of the top cover assembly (i.e., cover plate, terminal post and pressure plate) of the battery cell shown;

[0035] Figure 9 for Figure 7 Side view of the top cover assembly of the shown battery cell. Detailed Implementation

[0036] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0037] In the description of this application, 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", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0040] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0041] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0042] One embodiment of this application provides an electrical device, a battery, and a battery cell. The electrical device utilizes the following batteries or battery cells as its power source: vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, power tools, energy storage devices, amusement equipment, elevators, and lifting equipment, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, or electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.; energy storage devices can be energy storage walls, base station energy storage, container energy storage, etc.; amusement equipment can be carousels, drop towers, etc.

[0043] The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended vehicles, etc. For new energy vehicles, the aforementioned battery can serve as a driving power source, thereby replacing fossil fuels to provide propulsion. This application does not impose any special restrictions on the aforementioned electrical devices.

[0044] The aforementioned battery can be a battery pack or a battery module. When the battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and multiple battery cells. Multiple battery cells can be electrically connected in series, parallel, or a combination of series and parallel connections, and communicate with the battery management system, which controls and monitors the operating status of each battery cell. Alternatively, multiple battery cells can first be combined with a module management system to form a battery module, and then these battery modules can be electrically connected in series, parallel, or a combination of series and parallel connections to form a battery pack together with the battery management system.

[0045] Multiple battery cells can be mounted on supporting structures such as housings, frames, and brackets. Electrical connections between battery cells and between battery cells and the battery management system can be established via electrical connectors, which can be busbars. Alternatively, battery cells can be electrically connected via their respective terminals. For example, between two adjacent battery cells, one battery cell has a slot on its terminal, and the other battery cell has a corresponding insert on its terminal. The insert is inserted into the slot to achieve electrical connection. Therefore, for one battery cell, the aforementioned electrical connector can be the terminal of another battery cell. Similarly, battery cells and the battery management system can also be electrically connected via mutual insertion, which will not be elaborated further. The aforementioned battery cells can be lithium-ion, sodium-ion, or magnesium-ion batteries, and their external contours can be cylindrical, flat, cuboid, or other shapes, but are not limited to these. Specifically, in this embodiment, the aforementioned battery cell is a lithium-ion square battery.

[0046] The specific structure of the battery cell is described below with reference to the accompanying drawings. Please refer to... Figures 2 to 4 As shown, the battery cell includes a cover plate 10, an insulating plate, and an electrode assembly. The insulating plate includes an insulating plate body 21 and a pressure plate 22. The insulating plate body 21 is disposed on the side of the cover plate 10 facing the electrode assembly. The pressure plate 22 is disposed on the side of the insulating plate body 21 away from the cover plate 10 and has a positive electrode clamping section 23a and a negative electrode clamping section 25a. The electrode assembly includes a cell body and a positive electrode tab 321 and a negative electrode tab 323 connected to the cell body. The thickness of the positive electrode tab 321 is greater than the thickness of the negative electrode tab 323. The positive electrode tab 321 is located between the positive electrode clamping section 23a of the pressure plate 22 and the insulating plate body 21, and the negative electrode tab 323 is located between the negative electrode clamping section 25a of the pressure plate 22 and the insulating plate body 21. The width W1 of the positive electrode clamping section 23a is smaller than the width W2 of the negative electrode clamping section 25a.

[0047] When the positive electrode clamping section 23a and the negative electrode clamping section 25a of the pressure plate 22 are fastened to the insulating plate body 21, the positive electrode clamping section 23a exerts a pulling force on the positive electrode tab 321, and the negative electrode clamping section 25a exerts a pulling force on the negative electrode tab 323. Since the width W1 of the positive electrode clamping section 23a is set smaller than the width W2 of the negative electrode clamping section 25a, the width of the positive electrode clamping section 23a is narrowed. This significantly reduces the pulling force of the positive electrode clamping section 23a on the positive electrode tab 321 when the pressure plate 22 is fastened to the insulating plate body 21, thereby greatly reducing the risk of cracking at the root of the positive electrode tab 321.

[0048] It should be noted that both the positive electrode tab 321 and the negative electrode tab 323 are made of multiple layers of sheet material. Therefore, the positive electrode clamping section 23a and the negative electrode clamping section 25a of the pressure plate 22 are used to press the positive electrode tab 321 and the negative electrode tab 323 onto the insulating board body 21, respectively. This achieves the shaping and support of the positive electrode tab 321 and the negative electrode tab 323, and avoids the occurrence of adverse phenomena such as inverted insertion due to the positive electrode tab 321 and the negative electrode tab 323 being in a loose state.

[0049] Furthermore, the width dimensions W1 of the positive electrode clamping section 23a and W2 of the negative electrode clamping section 25a satisfy the following condition: 0.1mm ≤ W2 - W1 ≤ 10mm. Thus, by narrowing the width dimension of the positive electrode clamping section 23a, and controlling the narrowing range between 0.1mm and 10mm, the risk of cracking at the root of the positive electrode tab 321 can be reduced, while ensuring better shaping and support for the positive electrode tab 321 and the negative electrode tab 323, avoiding adverse phenomena such as inverted tab insertion. Optionally, the difference between the width dimension W2 of the negative electrode clamping section 25a and the width dimension W1 of the positive electrode clamping section 23a can be equal to 0.1mm, 0.5mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm or 10mm.

[0050] Furthermore, the width W2 of the negative electrode clamping section 25a satisfies: 80% × b ≤ W2 ≤ 100% × b. Here, b represents the thickness of the cell body. The cell body can include one cell 311 or multiple cells 311 arranged side-by-side. When the cell body includes only one cell 311, the thickness of the cell body is the thickness of a single cell 311. When the cell body includes multiple cells 311, the thickness of the cell body is the sum of the thicknesses of each cell 311. The thickness of the cell body is from 10 mm to 100 mm, and the cell group margin is from 50% to 97%.

[0051] Furthermore, the width dimension W1 of the positive electrode clamping section 23a and the width dimension W2 of the negative electrode clamping section 25a satisfy: 0mm ≤ (W2-W1)-Δh ≤ 2mm; where Δh represents the difference between the thickness dimension of the positive electrode tab 321 and the thickness dimension of the negative electrode tab 323. It should be noted that the thickness dimension of the positive electrode tab 321 refers to the sum of the thicknesses of each layer of the positive electrode tab 321, and the thickness dimension of the negative electrode tab 323 refers to the sum of the thicknesses of each layer of the negative electrode tab 323.

[0052] Please see Figure 5 and Figure 6 Specifically, in this embodiment, the width directions of both the positive electrode clamping section 23a and the negative electrode clamping section 25a are parallel to the first direction X1, and the thickness direction of the battery cell body is also parallel to the first direction X1. The distance between one end face of the negative electrode clamping section 25a in the first direction X1 and one end face of the battery cell body in the first direction X1 is L1. The distance between one end face of the positive electrode clamping section 23a in the first direction X1 and one end face of the battery cell body in the first direction X1 is L2, and L2 is greater than L1. Thus, by narrowing the width of the positive electrode clamping section 23a, the width dimension of the positive electrode clamping section 23a is smaller than that of the negative electrode clamping section 25a, thereby making L2 greater than L1. This further ensures that when the positive electrode clamping section 23a of the pressure plate 22 is fastened to the insulating plate body 21, the pulling force of the positive electrode clamping section 23a on the positive electrode tab 321 is reduced, thereby greatly reducing the risk of cracking at the root of the positive electrode tab 321.

[0053] It should be noted that, in some embodiments, the battery cell body includes two battery cells 311 arranged side by side along the first direction X1. Each battery cell 311 is provided with a positive electrode tab 321 and a negative electrode tab 323 on the side facing the cover plate 10, that is, the battery cell body is provided with a total of two positive electrode tabs 321 and two negative electrode tabs 323 on the side facing the cover plate 10. The positive electrode tabs 321 and negative electrode tabs 323 of each battery cell are arranged at intervals along a second direction X2 perpendicular to the first direction X1. The two positive electrode tabs 321 of the two battery cells 311 extend from both sides of the positive electrode clamping section 23a in the first direction X1 to the space between the positive electrode clamping section 23a and the insulating plate body 21, so that the positive electrode clamping section 23a simultaneously presses the two positive electrode tabs 321 onto the insulating plate body 21. The two negative tabs 323 of the two cells 311 extend from both sides of the negative electrode pressing section 25a in the first direction X1 to the space between the negative electrode pressing section 25a and the insulating plate body 21, so that the negative electrode pressing section 25a presses the two negative tabs 323 onto the insulating plate body 21 at the same time.

[0054] Furthermore, the distance between the two end faces of the negative electrode clamping section 25a in the first direction X1 and the two end faces of the cell body in the first direction X1 is L1. The distance between the two end faces of the positive electrode clamping section 23a in the first direction X1 and the two end faces of the cell body in the first direction X1 is L2, where L2 is greater than L1. Thus, by narrowing the width of the positive electrode clamping section 23a, the width of the positive electrode clamping section 23a is smaller than that of the negative electrode clamping section 25a, thereby making L2 greater than L1. This further ensures that when the positive electrode clamping section 23a of the pressure plate 22 is fastened to the insulating plate body 21, the pulling force of the positive electrode clamping section 23a on both sides of the positive electrode tabs 321 is reduced, thereby greatly reducing the risk of cracking at the root of each positive electrode tab 321.

[0055] In a specific embodiment, the battery cell further includes a positive terminal 41 and a negative terminal 43. The positive terminal 41 is insulated on the cover plate 10 and passes through the insulating plate body 21 to be electrically connected to the positive terminal tab 321. The negative terminal 43 is insulated on the cover plate 10 and passes through the insulating plate body 21 to be electrically connected to the negative terminal tab 323.

[0056] In a specific embodiment, the battery cell further includes a housing, at least one end of which has an opening. The electrode assembly is inserted into the housing through this opening. The cover plate 10 is placed over the opening of the housing to enclose the electrode assembly within the housing. An insulating plate body 21 is located on the side of the cover plate 10 facing the electrode assembly, serving to form insulation between the cover plate 10 and the electrode assembly. One end of the positive electrode tab 321 is connected to the cell body, and the other end is bent between the insulating plate body 21 and the positive electrode clamping section 23a; one end of the negative electrode tab 323 is connected to the cell body, and the other end is bent between the insulating plate body 21 and the negative electrode clamping section 25a.

[0057] It should be noted that because the positive electrode tab 321 is thicker than the negative electrode tab 323, uneven support for the cover plate 10 is likely to occur. Specifically, the portion of the cover plate 10 corresponding to the positive electrode tab 321 is higher, while the portion corresponding to the negative electrode tab 323 is lower. This results in the cover plate 10 not being flush with the opening end of the housing, significantly increasing the welding difficulty between the cover plate 10 and the housing. To avoid this unevenness between the cover plate 10 and the opening end of the housing, in some embodiments, please refer again... Figures 2 to 4 The thickness H1 of the positive electrode clamping section 23a is smaller than the thickness H2 of the negative electrode clamping section 25a. In other words, increasing the thickness of the negative electrode clamping section 25a and / or decreasing the thickness of the positive electrode clamping section 23a compensates for the thickness difference between the positive electrode tab 321 and the negative electrode tab 323, ensuring that the cover plate 10 is flush with the opening end of the shell, which greatly reduces the welding difficulty between the cover plate 10 and the shell.

[0058] Furthermore, the thickness H1 of the positive electrode clamping section 23a and the thickness H2 of the negative electrode clamping section 25a satisfy the following condition: 0.1mm ≤ H2 - H1 ≤ 2mm. Optionally, the difference between the thickness H2 of the negative electrode clamping section 25a and the thickness H1 of the positive electrode clamping section 23a can be equal to 0.1mm, 0.5mm, 1.0mm, 1.5mm, or 2.0mm.

[0059] Furthermore, the thickness H2 of the negative electrode clamping section 25a satisfies: 0.2mm ≤ H2 ≤ 1.5mm. Optionally, the thickness H2 of the negative electrode clamping section 25a can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, or 1.5mm.

[0060] Furthermore, the thickness H1 of the positive electrode clamping section 23a and the thickness H2 of the negative electrode clamping section 25a satisfy: H2 - H1 = Δh; where Δh represents the difference between the thickness of the positive electrode tab 321 and the thickness of the negative electrode tab 323. This ensures that the sum of the thicknesses of the positive electrode clamping section 23a and the positive electrode tab 321 is equal to the sum of the thicknesses of the negative electrode clamping section 25a and the negative electrode tab 323, thereby avoiding uneven support for the cover plate 10, ensuring that the cover plate 10 is flush with the opening end of the housing, and greatly reducing the welding difficulty between the cover plate 10 and the housing.

[0061] In embodiments of this application, the battery cell body includes at least one battery cell 311, which is formed by winding at least a positive electrode sheet, a separator, and a negative electrode sheet. Each turn of the positive electrode sheet can lead out a positive electrode tab, and the positive electrode sheets are stacked to form a positive electrode tab 321. That is, the positive electrode tab 321 includes multiple stacked positive electrode tabs, each of which is connected to the positive electrode sheet. Each turn of the negative electrode sheet can lead out a negative electrode tab, and the negative electrode tabs are stacked to form a negative electrode tab 323. That is, the negative electrode tab 323 includes multiple stacked negative electrode tabs, each of which is connected to the negative electrode sheet.

[0062] To prevent the positive and negative electrode plates from being exposed, the separator extends beyond the positive and negative electrode plates at the end of the cell 311 facing the cover plate 10. That is, compared to the positive and negative electrode plates, the separator is closer to the positive electrode clamping section 23a and the negative electrode clamping section 25a, ensuring that the positive and negative electrode plates are enclosed by the separator. Furthermore, at the end of the cell 311 facing the negative electrode clamping section 25a, the separator extends beyond the positive and negative electrode plates, and the interference between the negative electrode clamping section 25a and the separator is 0mm to 5mm.

[0063] It should be noted that the interference between the negative electrode pressing section 25a and the diaphragm refers to the degree to which the negative electrode pressing section 25a bends the diaphragm. For example, an interference of 0 mm means that the negative electrode pressing section 25a just contacts the diaphragm but does not bend it; an interference of 3 mm means that the negative electrode pressing section 25a bends the diaphragm downward by 3 mm; and an interference of 5 mm means that the negative electrode pressing section 25a bends the diaphragm downward by 5 mm.

[0064] In some embodiments, see Figures 2 to 4 As shown, the positive electrode clamping section 23a and the negative electrode clamping section 25a of the pressure plate 22 are separately configured, meaning that the positive electrode clamping section 23a and the negative electrode clamping section 25a of the pressure plate 22 are two separate components. Specifically... Figure 2 In the embodiment shown, the positive electrode pressing section 23a and the negative electrode pressing section 25a are respectively arranged at intervals along the left and right direction (i.e., the second direction X2) on the insulating plate body 21. The positive electrode pressing section 23a presses the positive electrode tab 321 onto the insulating plate body 21, and the negative electrode pressing section 25a presses the negative electrode tab 323 onto the insulating plate body 21.

[0065] In other embodiments, please refer to Figures 7 to 9 As shown, the positive electrode clamping section 23a and the negative electrode clamping section 25a of the pressure plate 22 are integrally formed. That is, the positive electrode clamping section 23a and the negative electrode clamping section 25a of the pressure plate 22 are connected to each other as a single component. The section of the pressure plate 22 corresponding to the positive electrode tab 321 is the positive electrode clamping section 23a, and the section of the pressure plate 22 corresponding to the negative electrode tab 323 is the negative electrode clamping section 25a. Specifically... Figure 7 In the embodiment shown, the pressure plate 22 is divided into two sections along the left-right direction (second direction X2). The section on the left is the positive electrode pressing section 23a, and the section on the right is the negative electrode pressing section 25a. The positive electrode pressing section 23a presses the positive electrode tab 321 onto the insulating plate body 21, and the negative electrode pressing section 25a presses the negative electrode tab 323 onto the insulating plate body 21.

[0066] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A battery cell, characterized in that, include: Cover plate (10); An insulating board includes an insulating board body (21) and a pressure plate (22). The pressure plate (22) is disposed on the side of the insulating board body (21) away from the cover plate (10) and has a positive electrode pressing section (23a) and a negative electrode pressing section (25a). The electrode assembly includes a battery cell body and a positive electrode tab (321) and a negative electrode tab (323) connected to the battery cell body. The thickness of the positive electrode tab (321) is greater than the thickness of the negative electrode tab (323). The positive electrode tab (321) is located between the positive electrode clamping section (23a) of the pressure plate (22) and the insulating plate body (21). The negative electrode tab (323) is located between the negative electrode clamping section (25a) of the pressure plate (22) and the insulating plate body (21). The width W1 of the positive electrode pressing section (23a) is smaller than the width W2 of the negative electrode pressing section (25a).

2. The battery cell according to claim 1, characterized in that, The positive electrode clamping section (23a) and the negative electrode clamping section (25a) of the pressure plate (22) are integrally formed; or The positive electrode pressing section (23a) and the negative electrode pressing section (25a) of the pressure plate (22) are separately arranged.

3. The battery cell according to claim 1, characterized in that, The width directions of both the positive electrode pressing section (23a) and the negative electrode pressing section (25a) are parallel to the first direction (X1); The distance between one end face of the negative electrode clamping section (25a) in the first direction (X1) and one end face of the battery cell body in the first direction (X1) is L1, and the distance between one end face of the positive electrode clamping section (23a) in the first direction (X1) and one end face of the battery cell body in the first direction (X1) is L2, and L2 > L1.

4. The battery cell according to claim 1, characterized in that, The width dimension W1 of the positive electrode clamping section (23a) and the width dimension W2 of the negative electrode clamping section (25a) satisfy: 0.1mm ≤ W2 - W1 ≤ 10mm; and / or The width dimension W2 of the negative electrode clamping section (25a) satisfies: 80% × b ≤ W2 ≤ 100% × b; where b represents the thickness dimension of the cell body; and / or The width dimension W1 of the positive electrode clamping section (23a) and the width dimension W2 of the negative electrode clamping section (25a) satisfy: 0mm≤(W2-W1)-Δh≤2mm; where Δh represents the difference between the thickness dimension of the positive electrode tab (321) and the thickness dimension of the negative electrode tab (323).

5. The battery cell according to claim 1, characterized in that, The thickness H1 of the positive electrode pressing section (23a) is smaller than the thickness H2 of the negative electrode pressing section (25a).

6. The battery cell according to claim 5, characterized in that, The thickness H1 of the positive electrode clamping section (23a) and the thickness H2 of the negative electrode clamping section (25a) satisfy: 0.1mm≤H2-H1≤2mm; and / or, the thickness H1 of the positive electrode clamping section (23a) and the thickness H2 of the negative electrode clamping section (25a) satisfy: H2-H1=Δh; where Δh represents the difference between the thickness of the positive electrode tab (321) and the thickness of the negative electrode tab (323).

7. The battery cell according to claim 5, characterized in that, The thickness H2 of the negative electrode pressing section (25a) satisfies: 0.2mm≤H2≤1.5mm.

8. The battery cell according to claim 5, characterized in that, The main body of the battery cell is formed by winding at least a positive electrode sheet, a separator and a negative electrode sheet. The positive electrode tab (321) includes multiple positive electrode tabs stacked together, each of which is connected to the positive electrode sheet. The negative electrode tab (323) includes multiple negative electrode tabs stacked together, each of which is connected to the negative electrode sheet. At one end of the cell body facing the negative electrode pressing section (25a), the separator extends beyond the positive electrode and the negative electrode, and the interference between the negative electrode pressing section (25a) and the separator is 0 mm to 5 mm.

9. A battery, characterized in that, Includes the battery cell as described in any one of claims 1 to 8.

10. An electrical device, characterized in that, Includes the battery as described in claim 9.

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