Battery cell, battery device, energy storage device, and electric device

Abstract

A battery cell (100), a battery device (200), an energy storage device (300), and an electric device (1000). The battery cell comprises a housing (110), an electrode assembly (120), and a cover plate assembly (130). The housing is provided with an opening (111). The electrode assembly is disposed in the housing and is provided with a tab (121). The cover plate assembly seals the opening and comprises a cover plate (131) and an insulating member (132). The cover plate is provided with a terminal post (140) and has at least one fixing hole (1311). The insulating member is located between the cover plate and the electrode assembly and is provided with at least one fixing column (1321) that fits into the fixing hole to fixedly connect the cover plate to the insulating member. The fixing column comprises a first portion (13211) and a second portion (13212); the first portion is located in the fixing hole, and the second portion is located on the side of the first portion facing away from the insulating member, the cross-sectional area of the second portion being greater than the cross-sectional area of the first portion. The cover plate assembly is configured to satisfy: n≥KM / (FS), where n is the number of fixing columns, M is the weight of the electrode assembly, S is the cross-sectional area of a single first portion, the value range of K is 5≤K≤9, and the value range of F is 15 N / mm2≤F≤25 N / mm2.

Description

Battery cells, battery packs, energy storage devices and electrical appliances

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 202422758654.2, filed on November 12, 2024, entitled “Battery Cell, Battery Device, Energy Storage Device and Power Consumption Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of battery technology, specifically a battery cell, battery device, energy storage device, and power consumption device. Background Technology

[0004] In the prior art, in order to protect the battery cells, an insulating component is usually installed between the cover plate of the battery cell and the electrode assembly. The insulating component can also prevent leakage of the battery cell to a certain extent and improve the safety of the battery cell.

[0005] In order to achieve a fixed connection between the cover plate and the insulating component, hot melt points are usually arranged between the insulating component and the cover plate. However, the existing hot melt points are easily broken during the assembly of the battery cell, which leads to the easy separation of the insulating component and the cover plate, affecting the performance of the battery cell. Summary of the Invention

[0006] Therefore, this application proposes a battery cell, a battery device, an energy storage device, and an electrical device, which can, to a certain extent, prevent the fixing points of the connecting cover and insulating parts from being pulled apart during the assembly of the battery cell.

[0007] A battery cell according to an embodiment of this application includes: a housing with an open end; an electrode assembly disposed within the housing, the electrode assembly having tabs; and a cover assembly disposed within the housing to cover the open end, the cover assembly including a cover plate and an insulating member, the cover plate having a terminal post electrically connected to the tabs, the insulating member being located between the cover plate and the electrode assembly, the cover plate having at least one fixing hole, and the insulating member having at least one fixing post cooperating with the fixing hole to fix the cover plate and the insulating member, the fixing post including a first part and a second part connected to each other, the first part being located within the fixing hole, the second part being located on the side of the first part away from the insulating member, the cross-sectional area of ​​the second part being larger than the cross-sectional area of ​​the first part; the cover assembly is configured to satisfy: n≥KM / (FS), where n is the number of fixing posts; M is the weight of the electrode assembly, the unit of M is N, the value range of M is 50N≤M≤120N; and S is the cross-sectional area of ​​a single first part, the unit of S is mm. 2 The value of K ranges from 5 to 9; the unit of F is N / mm. 2 The value of F ranges from 15 N / mm. 2 ≤F≤25N / mm 2 .

[0008] In the above technical solution, by setting the number of fixing posts n, the weight M of the electrode assembly, and the cross-sectional area S of the first part of a single fixing post to meet certain conditions, it is possible to use the fixing posts to achieve a stable connection between the cover plate and the insulating component. This avoids the phenomenon of the fixing posts between the cover plate and the insulating component being pulled apart due to the weight of the electrode assembly during the battery cell assembly process, thereby preventing the cover plate and the insulating component from separating. It also avoids the phenomenon that the electrode tabs of the electrode assembly are easily pulled and cracked under stress, thus avoiding affecting the performance of the battery cell to a certain extent, thereby improving the working performance of the battery cell.

[0009] Optionally, the first part is cylindrical, where S = π(D / 2). 2 Where D is the diameter of the first part, and the unit of D is mm.

[0010] In the above technical solution, a cylindrical fixing post can be used to achieve a stable connection between the cover plate and the insulating component, which can avoid separation of the cover plate and the insulating component to a certain extent, thereby improving the working performance of the battery cell.

[0011] Optionally, the cover plate assembly is configured to satisfy: 4≤n≤22, D≥2mm.

[0012] In the above technical solution, it is easy to set the number of fixing posts and the cross-sectional area of ​​a single first part within a suitable range, reducing the molding difficulty of the fixing posts. This is conducive to using multiple fixing posts to improve the connection strength between the cover plate and the insulating parts, achieving a stable connection between the cover plate and the insulating parts, and ensuring the performance of the battery cell to a certain extent.

[0013] Optionally, the cover plate assembly is configured to satisfy: 2.5mm≤D≤5mm.

[0014] In the above technical solution, while ensuring a stable connection between the cover plate and the insulating component using the fixing post, the manufacturing difficulty of the fixing post can be reduced and the space occupied by the fixing post can be reduced, which is conducive to improving the design flexibility of the cover plate assembly.

[0015] Optionally, 10 ≤ n ≤ 14.

[0016] In the above technical solution, the number of fixing posts is further optimized, so as to reduce the weight and manufacturing cost of the insulating parts, while also allowing the cross-sectional area of ​​a single first part to be set within a suitable range, ensuring that the cover plate and the insulating parts can be fixedly connected by using multiple fixing posts.

[0017] Optionally, the fixing hole includes a first fixing hole and a second fixing hole that are interconnected. The first fixing hole opens toward the insulating member, and the second fixing hole is located on the side of the first fixing hole away from the insulating member. At least a portion of the diameter of the second fixing hole is larger than the diameter of the first fixing hole. The first portion is located inside the first fixing hole, and the second portion is located inside the second fixing hole. The fixing post is a plastic part.

[0018] In the above technical solution, the fixing post can be prevented from falling out of the fixing hole to a certain extent, so that the fixing post can effectively achieve a stable connection between the cover plate and the insulating part.

[0019] Optionally, there are multiple fixing posts, some of which are spaced apart along the length direction of the insulating member, and some of which are spaced apart along the width direction of the insulating member.

[0020] In the above technical solution, multiple fixing posts can be set in both the length and width directions of the insulating component, so that the insulating component can be stably connected to the cover plate in both the length and width directions through the fixing posts. This further increases the connection strength between the cover plate and the insulating component, avoids the phenomenon of the cover plate and the insulating component separating due to the weight of the electrode assembly during the battery cell assembly process, and improves the working performance of the battery cell.

[0021] Optionally, the plurality of fixing posts spaced apart along the length direction of the insulating member are symmetrically arranged along a straight line containing the midpoint of the midpoint along the length direction of the insulating member; and / or, the plurality of fixing posts spaced apart along the width direction of the insulating member are symmetrically arranged along a straight line containing the midpoint of the midpoint along the width direction of the insulating member.

[0022] In the above technical solution, the cover plate and the insulating component can be subjected to uniform force at various positions in the length direction and / or width direction, thereby further realizing a stable connection between the cover plate and the insulating component.

[0023] Optionally, the insulating member has two through holes spaced apart along its length. The tabs include a positive tab and a negative tab, and the posts include a positive post and a negative post. The positive tab and the positive post are electrically connected through one of the through holes, and the negative tab and the negative post are electrically connected through the other through hole. In the length direction of the insulating member, the insulating member has a first side that is disposed opposite to each other. There are multiple fixing posts. At least some of the fixing posts are disposed between two of the through holes to form a first fixing post, and at least some of the fixing posts are disposed between the through hole and the first side to form a second fixing post.

[0024] In the above technical solution, the insulating component is stably connected to the cover plate through fixing posts at the middle and both ends in the length direction, which further increases the connection strength between the cover plate and the insulating component and avoids the phenomenon of the cover plate and the insulating component separating due to the weight of the electrode assembly during the battery cell assembly process.

[0025] Optionally, the end of the insulating member in the length direction is provided with a support boss protruding toward the electrode assembly, the support boss being adapted to support the electrode assembly, wherein, in the thickness direction of the cover plate, the second fixing post is disposed opposite to the support boss.

[0026] In the above technical solution, on the one hand, it is convenient to use the fixed column to strengthen the connection strength between the insulating component and the cover plate at the support boss position, improve the positional stability of the insulating component at the support boss position, and thus improve the positional stability of the support boss. This allows the support boss to stably support the electrode assembly and, to a certain extent, ensure the working performance of the support boss. On the other hand, it also allows the connection point between the cover plate and the insulating component to be set directly opposite the contact point between the support boss and the electrode assembly, thereby optimizing the force path of the battery cell. This makes the force transmission direction of the battery cell clearer and more concentrated. In this way, when the battery cell is subjected to external force, these forces can be transmitted sequentially along the fixed column, the support boss, and the electrode assembly, thereby avoiding excessive stress concentration or dispersion at the connection point between the cover plate and the insulating component to a certain extent, and extending the service life of the battery cell.

[0027] Optionally, the fixing post further includes a third fixing post, which is disposed between the through hole and the second fixing post.

[0028] In the above technical solution, it is advantageous to set the third fixing column close to the support boss, which can further strengthen the connection strength between the insulation component and the cover plate at the support boss position, improve the positional stability of the insulation component at the support boss position, improve the positional stability of the support boss, and optimize the force path of the battery cell, making the force transmission direction of the battery cell clearer and more concentrated.

[0029] Optionally, in the length direction of the insulating member, the insulating member has a first side disposed opposite to the first side, and the minimum distance B between the fixing post and the first side satisfies: 6mm≤B≤10mm; and / or, in the width direction of the insulating member, the insulating member has a second side disposed opposite to the first side, and the minimum distance A between the fixing post and the second side satisfies: 4mm≤A≤6mm.

[0030] In the above technical solution, while reducing the molding difficulty of the fixing post, it can also avoid damage to the first or second side during the molding process of the fixing post. Furthermore, the fixing post can effectively fix the two ends of the insulation component in the length direction and the two ends in the width direction, thereby improving the positional stability of the insulation component and improving its performance.

[0031] Optionally, the insulating member is provided with a through hole, and the electrode tab and the electrode post are electrically connected through the through hole; the cover plate is provided with a pressure relief mechanism, and in the length direction of the insulating member, the projection of the pressure relief mechanism on the insulating member is spaced apart from the through hole; the fixing post includes a first fixing post, which is located between the through hole and the projection of the pressure relief mechanism on the insulating member, and the first fixing post is offset from the pressure relief mechanism.

[0032] In the above technical solution, it is convenient to use fixed columns to strengthen the connection strength between the cover plate and the insulating parts on the outer periphery of the pressure relief mechanism, thereby strengthening the structural strength of the cover plate on the outer periphery of the pressure relief mechanism, so that the pressure relief mechanism can be stably installed on the cover plate, and to a certain extent, the working performance of the pressure relief mechanism can be guaranteed.

[0033] Optionally, the minimum distance between the projection of the fixing post on the cover plate and the pressure relief mechanism is E, where 50mm ≥ E ≥ 17mm.

[0034] In the above technical solution, the pressure relief mechanism is prevented from breaking or the connection between the pressure relief mechanism and the cover plate is broken when the cover plate and the insulating parts are connected by the fixed column to a certain extent. This ensures the performance of the pressure relief mechanism to a certain extent, and at the same time, the fixed column can be used to achieve a fixed connection between the cover plate and the insulating parts.

[0035] Optionally, in the longitudinal direction of the insulating member, a plurality of the first fixing posts are distributed on opposite sides of the pressure relief mechanism.

[0036] In the above technical solution, multiple fixed columns can be set on opposite sides of the pressure relief mechanism. This not only strengthens the connection between the cover plate and the insulating component, but also facilitates the strengthening of the connection between the cover plate and the insulating component near the pressure relief mechanism. This, in turn, strengthens the structural strength of the cover plate near the pressure relief mechanism and improves the structural stability of the cover plate. This, in turn, improves the positional stability of the pressure relief mechanism and, to a certain extent, ensures the performance of the pressure relief mechanism.

[0037] Optionally, a plurality of first fixing posts located on the same side of the pressure relief mechanism are arranged at intervals along the length and / or width direction of the insulating element.

[0038] In the above technical solution, a large number of first fixed columns are distributed on the opposite sides of the pressure relief mechanism, which effectively strengthens the connection strength between the cover plate and the insulating component near the pressure relief mechanism.

[0039] Optionally, the distance between two adjacent first fixing posts on the same side of the pressure relief mechanism along the length of the insulating member is C, where 50mm ≥ C ≥ 13mm.

[0040] In the above technical solution, the close proximity between adjacent fixed columns on the same side of the pressure relief mechanism can be avoided to a certain extent. While reducing the manufacturing difficulty of the fixed columns, it can also avoid mutual interference between the fixed columns during the connection process, thereby reducing the connection difficulty between the cover plate and the insulating parts. At the same time, it can also improve the performance of the fixed columns, so that the fixed columns can effectively achieve a stable connection between the cover plate and the insulating parts.

[0041] Optionally, a portion of the insulating member is recessed toward the electrode assembly to define a recessed groove, the recessed groove having a hollowed-out area, and the pressure relief mechanism being disposed corresponding to the hollowed-out area.

[0042] In the above technical solution, the hollow area is used to connect the pressure relief mechanism with the side of the insulating component away from the cover plate, so as to ensure that when the internal pressure of the battery cell rises due to overcharging, over-discharging, overcurrent and internal short circuit, the pressure relief mechanism can be used to achieve automatic and rapid pressure relief of the battery cell, thereby improving the safety of the battery cell.

[0043] Optionally, the battery cell further includes an insulating film, which wraps around the outer periphery of the electrode assembly, and the insulating element is fixedly connected to the insulating film.

[0044] In the above technical solution, the insulating component and the electrode assembly are fixedly connected, so that the insulating component can be stably placed between the cover plate and the electrode assembly, thus ensuring the working performance of the insulating component to a certain extent.

[0045] Optionally, the capacity of the battery cell is greater than 400Ah.

[0046] The above technical solution improves the battery's range.

[0047] Optionally, the outer casing has a dimension greater than or equal to 80 mm and less than or equal to 300 mm in the first direction; the outer casing has a dimension greater than or equal to 68 mm and less than or equal to 100 mm in the second direction; the outer casing has a dimension greater than or equal to 205 mm and less than or equal to 250 mm in the third direction; the first direction, the second direction and the third direction intersect each other.

[0048] The above technical solution enables the casing to be adapted to large-sized battery cells.

[0049] Optionally, the inner periphery of the opening is provided with a recess, and the end of the cover plate is accommodated in the recess and welded to the outer shell.

[0050] In the above technical solution, a fixed connection between the cover plate and the outer shell is achieved.

[0051] Optionally, the cover plate overlaps the end of the housing and is welded to the housing.

[0052] In the above technical solution, a fixed connection between the cover plate and the outer shell is achieved.

[0053] The battery device according to the embodiments of this application includes the aforementioned battery cell.

[0054] In the above technical solution, the performance of the battery device can be improved by using the aforementioned battery cells.

[0055] The energy storage device according to the embodiments of this application includes a plurality of the aforementioned battery cells or a plurality of the aforementioned battery devices, wherein the battery cells or the battery devices are used to store or provide electrical energy.

[0056] In the above technical solution, the working performance of the energy storage device can be improved by using the aforementioned battery cells or battery devices.

[0057] The electrical device according to the embodiments of this application includes the aforementioned battery cell, the aforementioned battery device, or the aforementioned energy storage device, wherein the battery cell or the battery device is used to store or provide electrical energy.

[0058] In the above technical solutions, the working performance of the electrical device can be improved by using the aforementioned battery cells, battery devices or energy storage devices. Attached Figure Description

[0059] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0060] Figure 1 is a schematic diagram of an electrical device according to some embodiments of this application.

[0061] Figure 2 is a schematic diagram of an energy storage device according to some embodiments of this application.

[0062] Figure 3 is a schematic diagram of a battery device according to some embodiments of this application.

[0063] Figure 4 is a front view of a battery cell according to some embodiments of this application.

[0064] Figure 5 is an exploded view of a battery cell according to some embodiments of this application.

[0065] Figure 6 is a schematic diagram of a cover plate assembly according to some embodiments of this application.

[0066] Figure 7 is a bottom view of a cover plate assembly according to some embodiments of this application.

[0067] Figure 8 is a cross-sectional view along line AA in Figure 7.

[0068] Figure 9 is a magnified view of region I in Figure 8.

[0069] Figure 10 is a schematic diagram of a cover plate according to some embodiments of this application.

[0070] Figure 11 is a bottom view of a cover plate according to some embodiments of this application.

[0071] Figure 12 is a top view of an insulating member according to some embodiments of the first aspect of this application.

[0072] Figure 13 is a schematic diagram of an insulating member according to some embodiments of the second aspect of this application.

[0073] Figure 14 is a schematic diagram of the cooperation between the insulating member and the fixing post according to some embodiments of this application.

[0074] Figure 15 is a schematic diagram of a battery cell without its casing according to some embodiments of this application.

[0075] Figure 16 is a side view of a battery cell without its casing according to some embodiments of this application.

[0076] Figure 17 is a front view of a battery cell according to some embodiments of this application, with the casing removed.

[0077] Figure 18 is a top view of a battery cell according to some embodiments of this application, with the casing removed.

[0078] Figure 19 is a top view of an insulating member according to some embodiments of the third aspect of this application.

[0079] Figure 20 is a top view of an insulating member according to some embodiments of the fourth aspect of this application.

[0080] Figure 21 is a top view of an insulating member according to some embodiments of the fifth aspect of this application.

[0081] Figure 22 is a top view of an insulating member according to some embodiments of the sixth aspect of this application.

[0082] Figure 23 is a top view of an insulating member according to some embodiments of the seventh aspect of this application.

[0083] Figure 24 is a top view of an insulating member according to some embodiments of the eighth aspect of this application.

[0084] Figure 25 is a partially enlarged cross-sectional view of a battery cell according to some embodiments of this application.

[0085] Figure 26 is a cross-sectional view of a battery cell according to some other embodiments of this application.

[0086] Figure 27 is a magnified view of a portion of region II in Figure 26.

[0087] Figure 28 is a table of tensile data for a fixed column tensile test of a cover plate assembly according to some embodiments of this application.

[0088] Figure 29 is a table of tensile data for a fixed post tensile test of a cover plate assembly according to some other embodiments of this application.

[0089] Reference numerals: 1000, electrical device; 100, battery cell; 110, casing; 111, opening; 1111, groove; 120, electrode assembly; 121, tab; 122. Insulating film; 130, cover plate assembly; 131, cover plate; 1311, fixing hole; 13111, first fixing hole; 13112, second fixing hole; 1312, overlapping protrusion; 132, insulating component; 1321, fixing post; 13211, first part; 13212, second part; 13213, first fixing post; 13214, second fixing post; 13215, third fixing post; 1322, supporting boss; 1323, first side; 1324, second side; 1325, hollow area; 1326, recess; 1327, through hole; 140, pole post; 150, pressure relief mechanism; 160, first fixing point; 200, battery device; 210, housing; 211, upper housing; 212, lower housing; 300, energy storage device; 400, controller; 500, motor. Detailed Implementation

[0090] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0091] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0092] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0093] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0094] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0095] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0096] In this application, "multiple" means two or more, including two.

[0097] In this application, the battery cell can be a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and the embodiments of this application are not limited in this regard. Similarly, the battery cell can be cylindrical, flat, cuboid, or other shapes, and the embodiments of this application are not limited in this regard either. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this application are not limited in this regard either.

[0098] For example, a battery cell typically includes a housing, an electrode assembly, and an electrolyte. The housing is used to contain the electrode assembly and the electrolyte, and the housing has at least one positive electrode post and at least one negative electrode post. The electrode assembly includes one or more electrodes, and the electrode assembly is formed by stacking or winding a positive electrode sheet, a negative electrode sheet, and a separator.

[0099] The positive electrode typically includes a positive current collector and a positive active material layer. The positive active material layer is directly or indirectly coated on the positive current collector, and multiple positive electrode tabs are stacked together and electrically connected to the positive electrode post. For example, the stacked positive electrode tabs can be directly welded to the positive electrode post to form an electrical connection; alternatively, the battery cell may also include a positive electrode adapter, with the stacked positive electrode tabs welded to one end of the adapter, and the other end of the adapter welded to the positive electrode post, thus forming an electrical connection between the positive electrode tabs and the positive electrode post.

[0100] The negative electrode generally includes a negative current collector and a negative active material layer. The negative active material layer is directly or indirectly coated on the negative current collector, and multiple negative electrode tabs are stacked together and electrically connected to the negative electrode post. For example, the stacked negative electrode tabs can be directly welded to the negative electrode post to form an electrical connection; alternatively, the battery cell may also include a negative electrode adapter piece, with the stacked negative electrode tabs welded to one end of the adapter piece, and the other end of the adapter piece welded to the negative electrode post, so that the negative electrode tabs and the negative electrode post form an electrical connection.

[0101] The material of the separator is not limited; for example, it can be polypropylene or polyethylene.

[0102] Currently, judging from market trends, the application of battery cells is becoming increasingly widespread. Battery cells are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace, among other fields.

[0103] As the application fields of battery cells continue to expand, the market demand for them is also constantly increasing.

[0104] In order to protect the battery cells, an insulating component is usually installed between the cover plate of the battery cell and the electrode assembly. The insulating component can also prevent leakage of the battery cell to a certain extent, improve the safety of the battery cell. The insulating component can also effectively support the end face of the electrode assembly. After the electrode assembly is installed in the casing and the cover plate is welded, the internal core of the electrode assembly is under slight pressure. Moreover, the electrode assembly is also in a vibrating environment during vehicle use. If the restraint of the electrode assembly is insufficient, it will easily affect the life of the electrode assembly or cause a short circuit. Therefore, the insulating component is installed to effectively support the end face of the electrode assembly to reduce the possibility of the electrode assembly moving up and down.

[0105] Therefore, the above can also be understood as setting an insulating component between the cover plate and the electrode assembly, which is beneficial to improving the safety, stability and service life of the battery cell, while enabling the battery cell to adapt to complex and ever-changing working environments.

[0106] In addition, to achieve a fixed connection between the cover plate and the insulating component, heat fusion points are usually arranged at the positions of the insulating component and the cover plate, except for the riveting at the pole position. This allows the insulating component and the cover plate to be connected together by heat fusion. Specifically, a stepped groove is dug inside the cover plate and a fixing post is set on the insulating component. After the fixing post is heat-fused by ultrasonic waves, its height decreases and fills the groove in the cover plate, forming a stepped cylinder to achieve a fixed connection between the cover plate and the insulating component. In order to ensure the connection strength between the cover plate and the insulating component, there are usually multiple heat fusion points.

[0107] However, due to the heavy weight of the JR (Jellyroll, a semi-finished electrode assembly without welded mechanical parts), during the production and assembly of the electrode assembly into the casing and pre-welding press-fit process, after multiple changes of operators or personnel rotations, there is a phenomenon where the JR's own weight causes impact and pulling on the insulating parts due to its falling. A simulation analysis of the force on the JR's interchangeable tongue was conducted on the insulating parts and the cover plate connected by the hot melt point. The simulation results show that during the JR's interchangeable tongue and 6mm drop (simulating free fall), the impact force on the insulating parts is several times the weight of the JR itself. This causes the hot melt point connecting the insulating parts and the cover plate to be easily broken, which means that the insulating parts and the cover plate are easily separated. In addition, there is a problem of the tabs being pulled and torn, which affects the performance of the battery cells.

[0108] To address the aforementioned issues, the relevant technology typically involves inverting the electrode assembly into the casing and then welding the cover plate to the battery cell's outer shell while the assembly is inverted. After welding, the battery cell is flipped to its upright position, thus changing the traditional top welding process to a side welding process. However, this solution requires significant changes to the welding equipment and factory layout, resulting in higher costs.

[0109] Based on the phenomenon that the heat-melting point connecting the insulating component and the cover plate is easily broken, the applicant noted that there are two ideas to improve the ease of separation between the insulating component and the cover plate: one is to increase the number of heat-melting points between the insulating component and the cover plate, and the other is to increase the tensile strength of a single heat-melting point.

[0110] Based on this, and referring to Figures 4-14, this application embodiment provides a battery cell 100. The battery cell 100 configures a cover plate assembly 130, including a cover plate 131 and an insulating member 132, such that n ≥ KM / (FS), where: n is the number of fixing posts 1321, which are used to fix and connect the cover plate 131 and the insulating member 132; M is the weight of the electrode assembly 120, with units of N, and the value range of M is 50N ≤ M ≤ 120N; and S is the cross-sectional area of ​​a single first portion 13211, with units of mm. 2 The first part 13211 is located in the fixing hole 1311 on the cover plate 131. The value range of K is 5≤K≤9. K can be understood as the multiple of the gravity of the electrode assembly 120 relative to its own weight when the electrode assembly 120 is exchanging the plug during the assembly of the battery cell 100. The unit of F is N / mm. 2 The value of F ranges from 15 N / mm. 2 ≤F≤25N / mm 2 F can be understood as the maximum tensile force that a single unit area of ​​the first part 13211 can withstand.

[0111] Based on this, FS can be understood as the maximum tensile force that a single first part 13211 can withstand, where KM can be understood as the gravitational impact that the electrode assembly 120 itself experiences during the assembly of the battery cell 100. The above formula n≥KM / (FS) can be transformed into: (FS)n≥KM. That is to say, the cover assembly 130 satisfies the following: the maximum tensile force that at least one or more fixing posts 1321 can withstand is greater than or equal to the gravitational impact that the electrode assembly 120 itself experiences during the assembly of the battery cell 100. In other words, it avoids the gravitational impact that the electrode assembly 120 itself experiences during the assembly of the battery cell 100 being greater than the tensile force that multiple fixing posts 1321 can withstand. This avoids the fixing posts 1321 from breaking due to the large gravitational impact that the electrode assembly 120 itself experiences during the assembly of the battery cell 100, so that the fixing posts 1321 can be used to achieve a stable connection between the cover 131 and the insulating component 132.

[0112] The above can also be understood as follows: by setting the cover plate assembly 130 to satisfy: n≥KM / (FS), the fixing post 1321 that fixes the cover plate 131 and the insulating part 132 can withstand the pulling force of the electrode assembly 120 falling due to its own weight, thus preventing the fixing post 1321 from breaking when the electrode assembly 120 falls due to its own weight. This allows the fixing post 1321 to be stably connected to the cover plate 131 and the insulating part 132 using the fixing post 1321. This solves the problem that when the electrode assembly 120 falls due to its own weight and pulls on the insulating part 132 during the tongue replacement process, the fixing post 1321 connecting the cover plate 131 and the insulating part 132 breaks, leading to the separation of the cover plate 131 and the insulating part 132. It also avoids the phenomenon that the electrode tab 121 of the electrode assembly 120 is pulled and cracked under force, thus avoiding the impact on the performance of the battery cell 100 to a certain extent, thereby improving the working performance of the battery cell 100.

[0113] At the same time, the above-mentioned settings can also avoid the equipment modification costs and capacity loss costs caused by changing the wire drawing equipment and welding process, thereby reducing costs.

[0114] This application also provides a battery device 200 including the aforementioned battery cells 100, as shown in FIG3. The battery device 200 refers to a single physical module comprising multiple battery cells 100 to provide higher voltage and capacity. For example, the battery device 200 mentioned in this application may include one or more battery packs for providing voltage and capacity. A battery pack may include multiple battery cells 100, which are connected in series, parallel, or mixed connections via busbars.

[0115] In some embodiments, the battery pack is typically formed by arranging a plurality of battery cells 100. As an example, the battery pack can be a battery module, which is formed by arranging and fixing a plurality of battery cells 100 into a single module. As an example, a battery module can be formed by bundling multiple battery cells 100 together with cable ties.

[0116] In some embodiments, as shown in FIG3, the battery device 200 generally includes a housing 210 for encapsulating one or more battery packs. The housing 210 can, to a certain extent, prevent liquids or other foreign objects from affecting the charging or discharging of the individual battery cells 100. Of course, the battery device 200 may also not include the housing 210.

[0117] In a specific example, battery device 200 can be understood as a battery pack.

[0118] In some embodiments, as shown in FIG3, the battery device 200 includes a battery cell 100 and a housing 210, with the battery cell 100 disposed within the housing 210. This allows the housing 210 to support and protect the battery cell 100, thereby improving the structural stability of the battery cell 100, extending its service life, and enhancing its safety during use.

[0119] The housing 210 can adopt various structures.

[0120] In some embodiments, as shown in FIG3, the housing 210 may include an upper housing 211 and a lower housing 212, the upper housing 211 and the lower housing 212 covering each other, the upper housing 211 and the lower housing 212 together defining a receiving cavity for accommodating the battery cell 100, thereby reducing the molding difficulty of the housing 210 and facilitating the placement of the battery cell 100 inside the housing 210.

[0121] The upper box 211 can be a hollow structure with one end open, and the lower box 212 can be a plate-like structure. The lower box 212 covers the open side of the upper box 211 (not shown in the example figure), so that the upper box 211 and the lower box 212 together define the receiving cavity; or, the lower box 212 can be a hollow structure with one end open, and the upper box 211 can be a plate-like structure (not shown in the example figure). The upper box 211 covers the open side of the lower box 212, so that the upper box 211 and the lower box 212 can also cooperate to define the receiving cavity; or, as shown in Figure 3, both the upper box 211 and the lower box 212 are hollow structures with one side open, and the open side of the upper box 211 covers the open side of the lower box 212 to define the receiving cavity.

[0122] It should be noted that the box 210 formed by the upper box 211 and the lower box 212 can be of various shapes, such as a cylinder, a cube, or a cuboid; the battery cell 100 can be of various shapes, such as a cylinder or a square.

[0123] This application embodiment also provides an energy storage device 300 (as shown in FIG2) including the above-mentioned battery cell 100 or battery device 200. The battery cell 100 or battery device 200 includes multiple units. The battery cell 100 or battery device 200 is used to store or provide electrical energy to a certain extent to ensure the performance of the energy storage device 300, so that the energy storage device 300 can effectively store electrical energy and release it to supply the power system when needed.

[0124] In some embodiments, the energy storage device 300 can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems, etc. The energy storage device 300 can store electrical energy as needed and output electrical energy when appropriate. For example, the energy storage device 300 can store electrical energy during off-peak hours and provide electrical energy to relevant users or electrical devices 1000 during peak hours.

[0125] This application embodiment also provides an electrical device 1000 (as shown in FIG1) that uses the above-mentioned battery cell 100, battery device 200 or energy storage device 300. The battery cell 100 or battery device 200 is used to store or provide electrical energy so as to provide electrical energy to the electrical device 1000, thereby ensuring the working performance of the electrical device 1000 to a certain extent.

[0126] The electrical device 1000 mentioned here can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc.

[0127] Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys; spacecraft can include airplanes, rockets, space shuttles, and spaceships; 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.

[0128] For ease of explanation, the following embodiments use a vehicle as an example to describe the structure of the electrical device 1000 of this application in detail.

[0129] Please refer to Figure 1, which shows that the electrical device 1000 is a vehicle. 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 electric vehicles, etc. The vehicle is equipped with a battery device 200, which can be located at the bottom, front, or rear of the vehicle. The battery device 200 can be used to power the vehicle; for example, the battery device 200 can serve as the vehicle's operating power source.

[0130] In some embodiments, as shown in FIG1, the vehicle may further include a controller 400 and a motor 500. The controller 400 is used to control the battery device 200 to supply power to the motor 500, for example, for the power needs of the vehicle during starting, navigation and driving.

[0131] In some embodiments of this application, the battery device 200 can not only serve as the operating power source for the vehicle, but also as the driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0132] The following description, with reference to the accompanying drawings, describes a battery cell 100 according to an embodiment of this application.

[0133] As shown in Figures 4 and 5, the battery cell 100 includes a housing 110, an electrode assembly 120, and a cover assembly 130.

[0134] As shown in Figure 5, the end of the outer casing 110 is provided with an opening 111. The opening 111 is used to enable communication between the inside and outside of the outer casing 110, which reduces the assembly difficulty of the outer casing 110 and the electrode assembly 120 to a certain extent, thereby reducing the assembly difficulty of the battery cell 100 and improving the assembly efficiency.

[0135] As shown in Figures 4 and 5, the electrode assembly 120 is disposed inside the housing 110, and the electrode assembly 120 includes tabs 121.

[0136] By placing the electrode assembly 120 inside the housing 110, it is not only convenient to form the battery cell 100, but the housing 110 can also protect the electrode assembly 120, extend the service life of the electrode assembly 120, and improve the safety of the electrode assembly 120.

[0137] Therefore, by providing an opening 111 at the end of the housing 110, it can also be understood that it is convenient to place the electrode assembly 120 in the housing 110.

[0138] In a specific example, the electrode assembly 120 is disposed inside the housing 110 through an opening 111, which reduces the difficulty of assembling the electrode assembly 120 and the housing 110.

[0139] Furthermore, by providing tabs 121 on the electrode assembly 120, current can be drawn out from inside the battery using the tabs 121 to form a circuit, thereby facilitating the charging and discharging function of the battery cell 100 and reducing the difficulty of using the battery cell 100.

[0140] As shown in Figures 4-13, the cover plate assembly 130 is disposed on the outer shell 110 to cover the opening 111. The cover plate assembly 130 includes a cover plate 131 and an insulating member 132. The cover plate 131 has an electrode post 140 electrically connected to the electrode tab 121. The insulating member 132 is located between the cover plate 131 and the electrode assembly 120. The cover plate 131 has at least one fixing hole 1311, and the insulating member 132 has at least one fixing post 1321 that mates with the fixing hole 1311 to fix the cover plate 131 and the insulating member 132 in a fixed connection. In other words, the cover plate 131 and the insulating member 132 are fixedly connected by at least one fixing hole 1311 on the cover plate 131 and at least one fixing post 1321 on the insulating member 132. This reduces the difficulty of connecting the cover plate 131 and the insulating member 132 and also helps to improve the connection strength between the cover plate 131 and the insulating member 132.

[0141] Specifically, by configuring the cover assembly 130 to include a cover 131 and an insulating member 132, and positioning the insulating member 132 between the cover 131 and the electrode assembly 120, the following advantages are achieved: First, the insulating member 132 can protect the electrode assembly 120, extend its service life, and improve its safety. Second, it can also prevent leakage in the battery cell 100 to a certain extent, thus improving its safety. Third, it can improve the insulation performance between the cover 131 and the electrode assembly 120, preventing electrolyte corrosion of the cover 131 from causing battery cell 100 failure and improving the performance of the battery cell 100. Fourth, it facilitates effective support for the end face of the electrode assembly 120, reducing the possibility of vertical movement of the electrode assembly 120.

[0142] In some embodiments, the insulating element 132 is made of plastic material, which reduces the manufacturing cost of the insulating element 132 and improves its insulation performance, thereby ensuring the working performance of the insulating element 132 to a certain extent.

[0143] Meanwhile, by providing a terminal post 140 electrically connected to the tab 121 on the cover plate 131, the current can be drawn out from inside the battery by using the terminal post 140 and the tab 121 together, thereby facilitating the charging and discharging function of the battery cell 100.

[0144] As shown in Figures 13 and 14, the fixing post 1321 includes a first part 13211 and a second part 13212 connected to each other. The first part 13211 is located inside the fixing hole 1311, and the second part 13212 is located on the side of the first part 13211 facing away from the insulating member 132. The cross-sectional area of ​​the second part 13212 is larger than that of the first part 13211. This is to allow the second part 13212 to limit the displacement of the first part 13211 and prevent the first part 13211 from coming out of the fixing hole 1311. This facilitates a stable connection between the cover plate 131 and the insulating member 132 by using the fixing hole 1311 and the fixing post 1321 together.

[0145] In a specific example, the fixing post 1321 on the insulating component 132 is positioned opposite the fixing hole 1311 on the cover plate 131. During the assembly of the cover plate assembly 130, the fixing post 1321 passes through the fixing hole 1311 and the first part 13211 of the fixing post 1321 is located inside the fixing hole 1311. By ultrasonically heat-melting the fixing post 1321, the height of the fixing post 1321 is reduced, and a second part 13212 is formed on the side of the first part 13211 away from the insulating component 132. The second part 13212 cooperates with the fixing hole 1311, thereby realizing the fixed connection between the cover plate 131 and the insulating component 132, and ensuring the connection strength between the cover plate 131 and the insulating component 132 to a certain extent.

[0146] Meanwhile, by hot-melting the fixing post 1321, the fixing post 1321 can be melted into the fixing hole 1311, so that the cover plate 131 and the insulating part 132 are integrated into one, reducing the riveting process, simplifying the manufacturing process of the battery cell 100 and reducing the production cost of the battery cell 100, while reducing the weight of the battery cell 100 without affecting the basic function of the battery cell 100. This makes the structure of the cover plate assembly 130 more compact, improves the space utilization of the battery cell 100, and allows a larger electrode assembly 120 to be placed inside the battery cell 100, thereby increasing the capacity of the battery cell 100.

[0147] The cover plate assembly 130 is configured to satisfy: n ≥ KM / (FS), where n is the number of fixing posts 1321; M is the weight of the electrode assembly 120, in N, and the value of M ranges from 50N ≤ M ≤ 120N; S is the cross-sectional area of ​​a single first part 13211, in mm. 2 The value of K ranges from 5 to 9; the unit of F is N / mm. 2 The value of F ranges from 15 N / mm. 2 ≤F≤25N / mm 2 .

[0148] It should be noted that, within the battery cell 100, in order to reduce the manufacturing difficulty of the fixing post 1321 and enable the fixing post 1321 to withstand a certain degree of tensile force, the maximum distance between any two points on the cross-sectional area of ​​the first part 13211 of the fixing post 1321 is usually set to 2.5mm to 5mm. By conducting multiple tensile tests on the first part 13211 (the specific procedure for the tensile test can be found below), it is found that the maximum tensile force per unit area of ​​the first part 13211 of a single fixing post 1321 is generally 15N / mm². 2 ~25N / mm 2 Therefore, in the above formula, F can be understood as the maximum tensile force that a single first part 13211 can withstand per unit area, and FS can be understood as the product of the maximum tensile force that a single first part 13211 can withstand per unit area and the cross-sectional area of ​​a single first part 13211, which is the maximum tensile force that a single first part 13211 can withstand. The K mentioned above can be understood as the multiple of the gravity of the electrode assembly 120 relative to its own weight when the electrode assembly 120 is exchanging the plug during the assembly process of the battery cell 100. M is the weight of the electrode assembly 120, but does not include the weight of the tab 121 and the electrolyte. When the battery cell 100 includes multiple electrode assemblies 120, M is the sum of the weights of the multiple electrode assemblies 120.

[0149] In other words, when the fixing holes 1311 on the cover plate 131 and the fixing posts 1321 on the insulating component 132 are used to form a fixed connection between the cover plate 131 and the insulating component 132, the number n of fixing posts 1321, the weight M of the electrode assembly 120, and the tensile force borne by a single fixing post 1321 satisfy: (FS)n ≥ KM. When there is only one fixing post 1321 connecting the cover plate 131 and the insulating component 132, the tensile force that one fixing post 1321 can bear is greater than or equal to the gravitational impact that the electrode assembly 120 itself experiences during the assembly of the battery cell 100. When there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, the tensile force that multiple fixing posts 1321 can bear is greater than or equal to the gravitational impact that the electrode assembly 120 itself experiences during the assembly of the battery cell 100. This design avoids the breakage of the fixing post 1321 due to the large impact of gravity on the electrode assembly 120 during the assembly of the battery cell 100. It ensures a stable connection between the cover plate 131 and the insulating component 132, preventing separation of the cover plate 131 and the insulating component 132. It also addresses the issue that the electrode assembly 120's excessive weight can cause it to drop and pull on the insulating component 132 during tongue replacement, leading to the breakage of the fixing post 1321 and the separation of the cover plate 131 and the insulating component 132. Furthermore, it avoids the phenomenon of the electrode tab 121 of the electrode assembly 120 being stretched and cracked, thus minimizing the impact on the performance of the battery cell 100 and improving its overall performance.

[0150] In other words, the fixing post 1321 of this application can not only realize the fixed connection between the cover plate 131 and the insulating component 132, but also avoid the phenomenon that the electrode assembly 120 will fall and break the fixing post 1321 due to its own weight to a certain extent. In this way, the cover plate 131 and the insulating component 132 will be separated during the assembly of the battery cell 100 to a certain extent, and the working performance of the battery cell 100 will be guaranteed to a certain extent.

[0151] Meanwhile, by setting the number n of the fixing posts 1321, the weight M of the electrode assembly 120, and the tensile force borne by a single fixing post 1321, the problem of the cover plate 131 and the insulating part 132 separating due to the weight of the electrode assembly 120 falling can be solved. This also avoids changing the wire pulling equipment and welding process, thereby avoiding equipment modification costs and production capacity loss costs, and reducing improvement costs.

[0152] It should be noted that the weight M of the electrode assembly 120 can be obtained through the following measurement method:

[0153] First, peel the cover plate assembly 130 and electrode assembly 120 from the outer casing 110. When the outer surface of the electrode assembly 120 is provided with an insulating film 122, tear off the insulating film 122 and separate the cover plate assembly 130 and electrode assembly 120. Then, cut off the tabs 121 (including the positive electrode tab and the negative electrode tab) of the electrode assembly 120. Then, lay out the remaining electrode assembly 120 flat, distinguish the positive electrode sheet, negative electrode sheet, and separator. Roll up the positive electrode sheet and separator, put them separately into a polyurethane bag, and then insert the steel gasket with a hole at the bottom. At the bottom of the centrifuge tube, roll the negative electrode sheet into a cylindrical shape with a diameter slightly smaller than the inner diameter of the centrifuge tube. Insert the tube into the centrifuge tube, seal the cap, and place it in a sample bag. Place the centrifuge tube in a centrifuge (model TDL-5-A), set the centrifugation speed to 3200 rpm, and the time to 30 minutes. Then, place the centrifuged positive electrode sheet and diaphragm into a drying oven and bake at 105 degrees Celsius for 10 hours. Finally, weigh the baked diaphragm, positive electrode sheet, and centrifuged negative electrode sheet separately, and add them together to get the weight of electrode assembly 120.

[0154] However, it should be noted that the weight of the electrode assembly 120 measured by the above measurement method is in kg. Multiplying the measured weight by 9.8N to 10N will give the weight M of the electrode assembly 120 of this application.

[0155] In this application, the weight M of the electrode assembly 120 is set to a range of 50N≤M≤120N. This not only improves the working performance of the electrode assembly 120, but also avoids the electrode assembly 120 from being too heavy, thereby avoiding the battery cell 100 from being too heavy. This prevents the overall weight of the electrical device 1000 from increasing due to the excessive weight of the battery cell 100, and improves the stability and safety of the electrical device 1000.

[0156] It should also be noted that when there is only one fixing post 1321 connecting the cover plate 131 and the insulating component 132, the maximum tensile force that the fixing post 1321 can withstand can be understood as the maximum tensile force that the insulating component 132 can withstand. When there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, and the cross-sectional areas of the first part 13211 of the multiple fixing posts 1321 are the same, the maximum tensile force that the multiple fixing posts 1321 can withstand in combination can be understood as the maximum tensile force that the insulating component 132 can withstand. When there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, but the cross-sectional areas of the first part 13211 of the multiple fixing posts 1321 are not the same, the maximum tensile force that the first part 13211 with the largest cross-sectional area can withstand can be understood as the maximum tensile force that the insulating component 132 can withstand. The maximum tensile force that the insulating component 132 can withstand can be obtained through the following measurement methods:

[0157] First, prepare the test piece and the push-pull force testing machine (Enpuda Instruments). The Enpuda Instruments machine has a fixture. The test piece includes an assembled cover plate 131 and an insulating component 132. The fixture includes a bottom shell and a top cover. The bottom shell has a receiving cavity with a top opening. The test piece is assembled in the receiving cavity, and the top cover closes at the opening. The cover plate 131 is fixedly connected to the bottom shell. The insulating component 132 is fixedly connected to the top cover by multiple screws. Multiple screws spaced apart along the length of the top cover are symmetrically arranged along a straight line containing the midpoint of the length direction of the top cover. Multiple screws spaced apart along the width of the top cover are also symmetrically arranged along a straight line containing the midpoint of the width direction of the top cover. This not only allows the test piece to be stably installed into the fixture using screws, but also ensures that the force on each position of the insulating component 132 is consistent during the tightening process, improving the testing efficiency. To ensure accuracy, after the test piece is locked, place the test piece, which is installed in the fixture, on the connector of the push-pull force testing machine. Finally, turn on the computer switch and the push-pull force testing machine switch, enter the software settings interface of Enpuda Instruments, click on static experiment, pull the top cover to move away from the bottom shell, thereby pulling the insulating part 132 to move away from the cover plate 131. Control the moving speed to 5mm / min and control the target load to 2000N. That is, during the process of pulling the insulating part 132, the force controlling the movement of the insulating part 132 is gradually increased from 0N to 2000N. During the process of increasing the force, detect whether the fixing post 1321 between the cover plate 131 and the insulating part 132 is broken. When the fixing post 1321 is broken, record the tensile force value of the load. This tensile force value is the maximum tensile force value that the insulating part 132 can withstand.

[0158] Specifically, when there is only one fixing post 1321 connecting the cover plate 131 and the insulating component 132, the maximum tensile force that the insulating component 132 can withstand is the maximum tensile force that a single first part 13211 can withstand. When there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, and the cross-sectional areas of the first parts 13211 of the multiple fixing posts 1321 are the same, the maximum tensile force that the insulating component 132 can withstand is divided by the number of fixing posts 1321 n to obtain the maximum tensile force that a single first part 13211 can withstand. When there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, but the cross-sectional areas of the first parts 13211 of the multiple fixing posts 1321 are not the same, the maximum tensile force that the insulating component 132 can withstand is the maximum tensile force that the first part 13211 with the largest cross-sectional area can withstand.

[0159] It should be noted that when there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, and the cross-sectional area of ​​the first part 13211 of the multiple fixing posts 1321 is the same, F can be understood as the maximum tensile force that any first part 13211 can withstand per unit area, and n is the sum of the number of multiple fixing posts 1321; when there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating component 132, but the cross-sectional area of ​​the first part 13211 of the multiple fixing posts 1321 is not the same, F can be understood as the maximum tensile force that the first part 13211 with the largest cross-sectional area can withstand per unit area, and n is a constant value, n=1.

[0160] In some embodiments, when there are multiple fixing posts 1321 connecting the cover plate 131 and the insulating member 132, the first portion 13211 of the multiple fixing posts 1321 has the same cross-sectional area, which not only reduces the manufacturing difficulty of the multiple fixing posts 1321, but also facilitates the use of multiple fixing posts 1321 to achieve a stable connection between the cover plate 131 and the insulating member 132.

[0161] Furthermore, once the maximum tensile force that a single first part 13211 can withstand is determined, dividing the maximum tensile force that a single first part 13211 can withstand by the cross-sectional area of ​​a single first part 13211 yields the maximum tensile force per unit area that a single fixed post 1321 can withstand, i.e., F. This can also be understood as the present application conducting multiple tensile tests on the 2.5mm to 5mm first parts 13211 using the aforementioned testing method, concluding that the maximum tensile force per unit area that a single fixed post 1321 can withstand is generally 15 N / mm². 2 ~25N / mm 2 .

[0162] As can be seen from the above structure, the battery cell 100 of this application embodiment achieves a fixed connection between the cover plate 131 and the insulating member 132 by providing a fixing hole 1311 in the cover plate 131 and a fixing post 1321 that cooperates with the fixing hole 1311 on the insulating member 132. This helps to reduce the difficulty of connecting the cover plate 131 and the insulating member 132, and at the same time, it can also improve the connection strength between the cover plate 131 and the insulating member 132.

[0163] Meanwhile, by setting the number n of the fixing posts 1321, the weight M of the electrode assembly 120, and the tensile force that a single fixing post 1321 can withstand to satisfy n≥KM / (FS), the purpose of using the fixing posts 1321 to achieve a stable connection between the cover plate 131 and the insulating component 132 is achieved. This avoids, to some extent, the phenomenon of the cover plate 131 and the insulating component 132 separating due to the weight of the electrode assembly 120 falling during the assembly of the battery cell 100. This solves the problem that the fixing posts 1321 connecting the cover plate 131 and the insulating component 132 break due to the excessive weight of the electrode assembly 120 during the tongue replacement process, which leads to the separation of the cover plate 131 and the insulating component 132. It also avoids the phenomenon of the electrode tab 121 of the electrode assembly 120 being pulled and cracked under stress, thus avoiding affecting the performance of the battery cell 100 to some extent and improving the working performance of the battery cell 100.

[0164] It is understandable that, compared with the prior art, the cover plate 131 and the insulating component 132 of this application are fixedly connected by the fixing post 1321. The number of fixing posts 1321 n, the weight M of the electrode assembly 120, and the tensile force that a single fixing post 1321 can withstand are set to satisfy: n≥KM / (FS), so as to achieve a stable connection between the cover plate 131 and the insulating component 132. To a certain extent, this avoids the phenomenon that the fixing post 1321 will break due to the weight of the electrode assembly 120 during the assembly of the battery cell 100. This also avoids the separation of the cover plate 131 and the insulating component 132 during the assembly of the battery cell 100, thus achieving a stable connection between the cover plate 131 and the insulating component 132. At the same time, it also avoids the electrode tab 121 of the electrode assembly 120 being pulled and cracked, thus avoiding affecting the performance of the battery cell 100 to a certain extent, thereby improving the working performance of the battery cell 100.

[0165] In some embodiments, the fixing post 1321 is a plastic part. While ensuring that the fixing post 1321 has a certain structural strength, it can also reduce the molding difficulty of the fixing post 1321, thereby making it easier to set the fixing post 1321 with a first part 13211 and a second part 13212 that are connected to each other, so as to facilitate the mating connection of the cover plate 131 and the insulating member 132 using the fixing post 1321, and reduce the difficulty of mating connection between the cover plate 131 and the insulating member 132.

[0166] Therefore, in the above formula, F can be understood as the maximum tensile force that a single first part 13211 formed as a plastic part can withstand per unit area.

[0167] In some embodiments, the fixing post 1321 is made of PP (Polypropylene), which reduces the manufacturing cost of the fixing post 1321 while making it a plastic part.

[0168] Of course, in some other embodiments, the fixing post 1321 may also be made of PE (Polyethylene).

[0169] In some embodiments, K = 5, 6, 7, 8, or 9, etc.

[0170] In some embodiments, M = 50N, 60N, 70N, 80N, 90N, 100N, 110N, or 120N, etc.

[0171] In some embodiments, F = 15 N / mm 2 16N / mm 2 17N / mm 2 18N / mm 2 19N / mm 2 20N / mm 2 21N / mm 2 22N / mm 2 23N / mm 2 24N / mm 2 Or 25N / mm 2 .

[0172] In some embodiments, as shown in Figures 14 and 15, the first portion 13211 is cylindrical, and S = π(D / 2). 2 Where D is the diameter of the first part 13211, and the unit of D is mm. This can be understood as follows: when the first part 13211 is cylindrical, the cover assembly 130 is constructed to satisfy:

[0173] That is, n≥4KM / (FπD) 2 ).

[0174] With the above settings, the maximum tensile force that a single fixed column 1321 can withstand per unit area is defined as 20 N / mm. 2 When n≥4KM / (FπD) 2 This can be converted to n≥4KM / (20πD) 2 That is, n≥KM / (5πD) 2 ).

[0175] In summary, when the first part 13211 is cylindrical, the cover plate assembly 130 is constructed to satisfy: n≥KM / (5πD) 2), where n is the number of fixed posts 1321; M is the weight of electrode assembly 120, the unit of M is N, and the value of M ranges from 50N ≤ M ≤ 120N; 5πD 2 The maximum tensile force that a single first part 13211 can withstand; the value of K is in the range of 5≤K≤9. Through the above settings, the cylindrical fixing post 1321 can effectively achieve a stable connection between the cover plate 131 and the insulating part 132, and to a certain extent avoid the separation of the cover plate 131 and the insulating part 132, thereby improving the working performance of the battery cell 100.

[0176] Of course, in some other embodiments, the first part 13211 is not limited to being formed as a cylinder, that is, the cross-sectional area of ​​the first part 13211 is not limited to being formed as a circle, and the cross-sectional area of ​​the first part 13211 can also be formed as a rectangle, a square or a hexagon, etc.

[0177] In some embodiments, as shown in Figures 7, 8, and 9, the fixing hole 1311 includes a first fixing hole 13111 and a second fixing hole 13112 that are interconnected. The first fixing hole 13111 opens toward the insulating member 132, and the second fixing hole 13112 is located on the side of the first fixing hole 13111 away from the insulating member 132. At least a portion of the diameter of the second fixing hole 13112 is larger than the diameter of the first fixing hole 13111. A first portion 13211 is located within the first fixing hole 13111, and a second portion 13212 is located within the second fixing hole 13112. This design aims to prevent the fixing post 1321 from falling out of the fixing hole 1311 to a certain extent, thereby enabling a stable connection between the cover plate 131 and the insulating member 132 using the fixing post 1321.

[0178] Meanwhile, by using the fixing post 1321 to replace the traditional riveting process, the manufacturing process of the battery cell 100 can be simplified, and the overall weight and production cost of the battery cell 100 can be reduced.

[0179] In some implementations, the fixing post 1321 and the insulating component 132 are integrally formed. This integrated design not only improves the assembly efficiency of the battery cell 100, but also enhances the connection strength between the fixing post 1321 and the insulating component 132, thus preventing the fixing post 1321 from falling off before heat fusion to a certain extent. This allows the fixing post 1321 to effectively achieve a stable connection between the cover plate 131 and the insulating component 132.

[0180] Of course, in some other embodiments, the fixing post 1321 and the insulating member 132 can also be formed as separate parts. That is, the fixing post 1321 and the insulating member 132 are processed and formed separately. After the fixing post 1321 and the insulating member 132 are processed, they can be bonded, welded or otherwise attached to the fixing post 1321 and the insulating member 132, which can also achieve the purpose of placing the fixing post 1321 on the insulating member 132.

[0181] In some embodiments, the cover assembly 130 is configured to satisfy: 4≤n≤22, D≥2mm. It should be noted that in n≥KM / (FS), the number n of the fixing posts 1321 is inversely proportional to the cross-sectional area S of a single first part 13211, that is, the number n of the fixing posts 1321 is inversely proportional to the diameter D of the first part 13211. When the diameter D of the first part 13211 is small, a larger number of fixing posts 1321 are required, which increases the molding difficulty of the fixing posts 1321. Therefore, this application sets D to satisfy D≥2mm, which not only increases the tensile force of a single fixing post 1321, enabling the fixing post 1321 to support the heavier electrode assembly 120, and enhances the compatibility, but also avoids the electrode assembly 120 from breaking the fixing post 1321 due to its own weight to a certain extent, thus improving the performance of the fixing post 1321. This allows the fixing post 1321 to achieve a stable connection between the cover plate 131 and the insulating part 132, and also avoids setting a large number of fixing posts 1321 to a certain extent, reducing the molding difficulty of the fixing post 1321.

[0182] Meanwhile, when the number n of fixing posts 1321 is large, it increases the weight and manufacturing cost of the insulating component 132, and also increases the manufacturing difficulty of the fixing posts 1321. When the number n of fixing posts 1321 is small, in order to achieve a stable connection between the cover plate 131 and the insulating component 132, it is necessary to increase the cross-sectional area of ​​the first part 13211, increasing the manufacturing difficulty of the first part 13211. Based on this, the number n of fixing posts 1321 is set to satisfy: 4≤n≤22, which allows for the increase of the number of fixing posts 1321. While reducing the number of fixed posts 1321, it also avoids setting too many fixed posts 1321 and avoids having a large cross-sectional area of ​​the first part 13211. This makes it easier to use multiple fixed posts 1321 to fix and connect the cover plate 131 and the insulating component 132, thereby improving the connection strength between the cover plate 131 and the insulating component 132 and further realizing the stable connection between the cover plate 131 and the insulating component 132. To a certain extent, it avoids the cover plate 131 and the insulating component 132 from separating due to the weight of the electrode assembly 120, thereby improving the working performance of the insulating component 132.

[0183] In other words, by setting the cover plate assembly 130 to satisfy: 4≤n≤22, D≥2mm, the manufacturing difficulty of the fixing post 1321 is reduced, while also improving the connection strength between the cover plate 131 and the insulating component 132, achieving a stable connection between the cover plate 131 and the insulating component 132, and ensuring the performance of the battery cell 100 to a certain extent.

[0184] Specifically, the number of fixed posts 1321 n = 4, 6, 8, 10, 12, 14, 16, 18, 20 or 22, etc.; the diameter D of the first part 13211 = 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, etc.

[0185] Specifically, when the number of fixed posts 1321, n, is 8, the arrangement of the 8 fixed posts 1321 can be seen in Figure 13; when the number of fixed posts 1321, n, is 10, the arrangement of the 10 fixed posts 1321 can be seen in Figure 19; when the number of fixed posts 1321, n, is 12, the arrangement of the 12 fixed posts 1321 can be seen in Figure 20; and when the number of fixed posts 1321, n, n, is 14, the arrangement of the 14 fixed posts 1321 can be seen in Figure 20. The arrangement of the fixing columns 1321 can be seen in Figure 21; when the number of fixing columns 1321 n is 16, the arrangement of the 16 fixing columns 1321 can be seen in Figure 12 or Figure 22; when the number of fixing columns 1321 n is 18, the arrangement of the 18 fixing columns 1321 can be seen in Figure 23; when the number of fixing columns 1321 n is 20, the arrangement of the 20 fixing columns 1321 can be seen in Figure 24.

[0186] In some embodiments, 10 ≤ n ≤ 14. This further optimizes the number of fixing posts 1321, reducing the weight and manufacturing cost of the insulating component 132 while allowing the cross-sectional area of ​​a single first portion 13211 to be set within a suitable range. This ensures that multiple fixing posts 1321 can be used to fix the cover plate 131 and the insulating component 132, improving the connection strength between them and further achieving a stable connection. This also helps to prevent the cover plate 131 and the insulating component 132 from separating due to the weight of the electrode assembly 120, thereby improving the working performance of the insulating component 132.

[0187] In some embodiments, the cover assembly 130 is configured to satisfy: 2.5mm ≤ D ≤ 5mm. When the diameter D of the first portion 13211 is small, a larger number of fixing posts 1321 are typically required to prevent the first portion 13211 from breaking, thus reducing the manufacturing difficulty of multiple fixing posts 1321. When the diameter D of the first portion 13211 is large, it not only increases the manufacturing difficulty of the fixing posts 1321 but also causes the fixing posts 1321 to occupy a larger space, affecting the design flexibility of the cover assembly 130.

[0188] Based on this, the diameter D of the first part 13211 is set to satisfy: 2.5mm≤D≤5mm. While ensuring that the cover plate 131 and the insulating part 132 can be stably connected by using the fixing post 1321, the manufacturing difficulty of the fixing post 1321 can be reduced and the space occupied by a single fixing post 1321 can be reduced, which is conducive to improving the design flexibility of the cover plate assembly 130.

[0189] Optionally, the diameter D of the first part 13211 is 2.5mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, etc.

[0190] It should be noted that this application conducted hot melt point tensile tests on cover plate assemblies 130 from different production batches with D=2.5mm and D=4mm. When D=2.5mm, as shown in Figure 28, the average tensile force that the hot melt point of multiple insulating components 132 can withstand is mean=118N, the standard deviation of tensile force σ=18N, and the lower limit of tensile force = mean-3σ=64N. When D=4mm, as shown in Figure 29, the average tensile force that the hot melt point of multiple insulating components 132 can withstand is mean=158N, the standard deviation of tensile force σ=26N, and the lower limit of tensile force = mean-3σ=78N. In other words, compared with the fixing post 1321 with D=2.5mm, the fixing post 1321 with D=4mm has a significantly improved tensile force, which is beneficial to reducing the number of fixing posts 1321 and reducing the molding difficulty of the fixing posts 1321.

[0191] Based on this, in the specific example, the diameter D of the first part 13211 is selected as 4mm to effectively increase the tensile strength of the fixing post 1321, thereby preventing the electrode assembly 120 from breaking the fixing post 1321 due to its own weight, improving the performance of the fixing post 1321, and thus achieving a stable connection between the insulating part 132 and the cover plate 131. At the same time, it can also reduce the number of fixing posts 1321.

[0192] In some embodiments, as shown in FIG12, there are multiple fixing posts 1321, some of which are spaced apart along the length direction of the insulating member 132, and some of which are spaced apart along the width direction of the insulating member 132. The length direction of the insulating member 132 can be understood as the X direction shown in FIG12, and the width direction of the insulating member 132 can be understood as the Y direction shown in FIG12. This also means that there are at least two fixing posts 1321 along the length direction of the insulating member 132, and correspondingly, at least two fixing posts 1321 along the width direction of the insulating member 132. This allows the insulating member 132 to form a stable connection with the cover plate 131 in both the length and width directions via the fixing posts 1321, further increasing the connection strength between the cover plate 131 and the insulating member 132. This prevents the cover plate 131 and the insulating member 132 from separating during the assembly of the battery cell 100 due to the weight of the electrode assembly 120, thereby improving the working performance of the battery cell 100.

[0193] In some embodiments, as shown in FIG12, a plurality of fixing posts 1321 spaced apart along the length of the insulating member 132 are symmetrically arranged along the line containing the midpoint of the insulating member 132 along its length. This ensures that when the cover plate 131 and the insulating member 132 are fixedly connected using the plurality of fixing posts 1321 along the length of the insulating member 132, the cover plate 131 and the insulating member 132 are subjected to uniform force at various positions along the length, which is beneficial for achieving a stable connection between the cover plate 131 and the insulating member 132.

[0194] In some embodiments, as shown in FIG12, a plurality of fixing posts 1321 spaced apart in the width direction of the insulating member 132 are symmetrically arranged along a straight line containing the midpoint of the midpoint in the width direction of the insulating member 132. Thus, when the cover plate 131 and the insulating member 132 are fixedly connected using the plurality of fixing posts 1321 in the width direction of the insulating member 132, the cover plate 131 and the insulating member 132 are subjected to uniform force at various positions in the width direction, further achieving a stable connection between the cover plate 131 and the insulating member 132.

[0195] In a specific example, as shown in Figure 12, multiple fixing posts 1321 spaced apart along the length of the insulating member 132 are symmetrically arranged along the line containing the midpoint of the insulating member 132 along its length, and the same multiple fixing posts 1321 spaced apart along the width of the insulating member 132 are symmetrically arranged along the line containing the midpoint of the insulating member 132 along its width. This maximizes the stable connection between the cover plate 131 and the insulating member 132.

[0196] In some embodiments, as shown in FIG12, the insulating member 132 is provided with two through holes 1327 spaced apart along its length. The tab 121 includes a positive tab and a negative tab, and the terminal 140 includes a positive terminal and a negative terminal. The positive tab and the positive terminal are electrically connected through one of the through holes 1327, and the negative tab and the negative terminal are electrically connected through the other through hole 1327. This reduces the difficulty of electrically connecting the tab 121 and the terminal 140, thereby facilitating the use of the tab 121 and the terminal 140 to draw out current, form a circuit, realize the charging and discharging function of the battery cell 100, and reduce the difficulty of using the battery cell 100.

[0197] It should be noted that the positive electrode tab and the positive electrode post can be directly connected to form an electrical connection. Alternatively, a positive electrode adapter can be provided between the positive electrode tab and the positive electrode post, which can be electrically connected to both the positive electrode tab and the positive electrode post, thus achieving a matching connection between the positive electrode tab and the positive electrode post. Similarly, the negative electrode tab and the negative electrode post can also be directly connected to form an electrical connection. Alternatively, a negative electrode adapter can be provided between the negative electrode tab and the negative electrode post, which can be electrically connected to both the negative electrode tab and the negative electrode post, thus achieving a matching connection between the negative electrode tab and the negative electrode post.

[0198] In some embodiments, as shown in FIG12, the insulating member 132 has a first side 1323 disposed opposite to each other in the length direction of the insulating member 132, and there are multiple fixing posts 1321. At least some of the fixing posts 1321 are disposed between two through holes 1327 to form a first fixing post 13213, and at least some of the fixing posts 1321 are disposed between the through hole 1327 and the first side 1323 to form a second fixing post 13214. This arrangement ensures that at least some of the fixing posts 1321 are positioned near the middle of the insulating member 132 along its length, and at least some of the fixing posts 1321 are positioned near the ends of the insulating member 132 along its length. This allows the middle of the insulating member 132 and both ends of the insulating member 132 along its length to form a stable connection with the cover plate 131 through multiple fixing posts 1321. This increases the connection strength between the cover plate 131 and the insulating member 132, achieving a stable connection between the cover plate 131 and the insulating member 132. This further prevents the cover plate 131 and the insulating member 132 from separating due to the weight of the electrode assembly 120 during the assembly of the battery cell 100, thereby improving the working performance of the battery cell 100.

[0199] In some embodiments, as shown in Figures 12 and 13, the second fixing post 13214 and the first fixing post 13213 are arranged along the width direction of the insulating member 132, so that the multiple fixing posts 1321 are evenly distributed at the ends and middle of the insulating member 132 in the length direction, thereby enabling the two ends and the middle of the insulating member 132 in the length direction to form a stable connection with the cover plate 131 through the multiple fixing posts 1321.

[0200] In summary, multiple fixing posts 1321 are provided at both ends and the middle of the insulating member 132 along its length. The multiple fixing posts 1321 at the ends and the multiple fixing posts 1321 in the middle are arranged along the width of the insulating member 132, so that the insulating member 132 is connected to the cover plate 131 through the multiple fixing posts 1321. The multiple fixing posts 1321 are evenly distributed on the insulating member 132, which helps to enhance the connection strength between the cover plate 131 and the insulating member 132.

[0201] In some embodiments, as shown in Figures 5, 6, and 13, the end of the insulating member 132 along its length is provided with a support boss 1322 protruding toward the electrode assembly 120. The support boss 1322 is adapted to support the electrode assembly 120. In the thickness direction of the cover plate 131, a second fixing post 13214 is positioned opposite the support boss 1322. By providing the support boss 1322 to support the electrode assembly 120, the electrode assembly 120 is positioned to limit its movement, improving its positional stability and, to a certain extent, ensuring its operational performance.

[0202] Meanwhile, by aligning the second fixing post 13214 with the support boss 1322, it facilitates, on the one hand, strengthening the connection between the insulating component 132 and the cover plate 131 at the support boss 1322 position, improving the positional stability of the insulating component 132 at the support boss 1322 position, and thus improving the positional stability of the support boss 1322. This allows the support boss 1322 to stably support the electrode assembly 120, ensuring the working performance of the support boss 1322 to a certain extent. On the other hand, it facilitates the connection between the cover plate 131 and the insulating component 132. The connection point is positioned directly opposite the contact point between the support boss 1322 and the electrode assembly 120, thereby optimizing the force path of the battery cell 100. This makes the force transmission direction of the battery cell 100 more clear and concentrated. When the battery cell 100 is subjected to external forces, these forces can be transmitted sequentially along the fixing post 1321, the support boss 1322, and the electrode assembly 120. This, to a certain extent, avoids excessive stress concentration or dispersion at the connection between the cover plate 131 and the insulating component 132, thus extending the service life of the battery cell 100.

[0203] In some embodiments, the support boss 1322 and the insulating member 132 are integrally formed. While reducing the molding difficulty of the support boss 1322, the connection strength between the support boss 1322 and the insulating member 132 can also be enhanced, so that the support boss 1322 can be stably set on the insulating member 132, thereby improving the positional stability of the support boss 1322 and facilitating the improvement of the support performance of the support boss 1322.

[0204] Of course, in some other embodiments, the support boss 1322 and the insulating member 132 can also be formed as separate parts. After the support boss 1322 and the insulating member 132 are processed separately, the support boss 1322 and the insulating member 132 are connected, which can also realize that the support boss 1322 is provided on the insulating member 132.

[0205] In some embodiments, as shown in Figures 12 and 13, the support boss 1322 is provided with a plurality of second fixing posts 13214. The cooperation of the plurality of second fixing posts 13214 can further enable the insulating member 132 at the position of the support boss 1322 and the cover plate 131 to form a stable connection, thereby further improving the positional stability of the support boss 1322.

[0206] In some embodiments, as shown in Figures 21-24, the fixing post 1321 further includes a third fixing post 13215, which is disposed between the through hole 1327 and the second fixing post 13214. Since the second fixing post 13214 is directly opposite the support boss 1322, by disposing the third fixing post 13215 between the through hole 1327 and the second fixing post 13214, it is convenient to provide the fixing post 1321 (third fixing post 13215) in the area of ​​the insulating member 132 near the support boss 1322. This can be understood as providing the fixing post 1321 (second fixing post 13214) not only at the position directly opposite the support boss 1322, but also at a position near the support boss 1322. A fixing post 1321 (third fixing post 13215) is placed to further strengthen the connection strength between the insulating component 132 and the cover plate 131 at the position of the supporting boss 1322, improve the positional stability of the insulating component 132 at the position of the supporting boss 1322, improve the positional stability of the supporting boss 1322, and to a certain extent ensure the working performance of the supporting boss 1322. At the same time, it is also conducive to optimizing the force path of the battery cell 100, making the force transmission direction of the battery cell 100 clearer and more concentrated.

[0207] In this case, a third fixing post 13215 may be provided in the area of ​​the insulating member 132 near the supporting boss 1322, or multiple third fixing posts 13215 may be provided, without specific restrictions.

[0208] In some embodiments, as shown in Figures 5, 15, 16, and 17, the battery cell 100 further includes an insulating film 122, which wraps around the outer periphery of the electrode assembly 120. A support boss 1322 is thermally fused to the insulating film 122. This allows the support boss 1322 to support the electrode assembly 120, improving the positional stability of the electrode assembly 120.

[0209] In some embodiments, as shown in FIG12, the insulating member 132 has a first side 1323 disposed opposite to each other along its length. The minimum distance B between the fixing post 1321 and the first side 1323 satisfies: 6mm ≤ B ≤ 10mm. When the minimum distance between the fixing post 1321 and the first side 1323 is small, it increases the difficulty of molding the fixing post 1321 and poses a risk of damaging the first side 1323 during the molding process, affecting the performance of the insulating member 132. When the minimum distance between the fixing post 1321 and the first side 1323 is large, it is impossible to use the fixing post 1321 to fix the two ends of the insulating member 132 along its length, affecting the fixing effect of the insulating member 132.

[0210] Therefore, this application sets the minimum distance B between the fixing post 1321 and the first side 1323 to satisfy: 6mm≤B≤10mm. This reduces the molding difficulty of the fixing post 1321, avoids damage to the first side 1323 during the molding process, and allows the fixing post 1321 to effectively fix the two ends of the insulating member 132 along its length, improving the positional stability of the insulating member 132 and thus enhancing its performance.

[0211] Optionally, the minimum spacing B between the fixed post 1321 and the first side 1323 is 6mm, 7mm, 8mm, 9mm or 10mm, etc.

[0212] In some embodiments, as shown in FIG12, the insulating member 132 has a second side 1324 disposed opposite to the insulating member 132 in the width direction, and the minimum distance A between the fixing post 1321 and the second side 1324 satisfies: 4mm≤A≤6mm. The beneficial effects can be seen in the beneficial effects of setting the minimum distance B between the fixing post 1321 and the first side 1323 to satisfy 6mm≤B≤10mm, which will not be elaborated here.

[0213] Optionally, the minimum distance between the fixed post 1321 and the second side 1324 is 4mm, 4.5mm, 5mm, 5.5mm or 6mm, etc.

[0214] In some embodiments, as shown in FIG12, the insulating member 132 is provided with a through hole 1327, and the tab 121 and the post 140 are electrically connected through the through hole 1327. This enables the tab 121 and the post 140 to be connected, reducing the difficulty of connecting the tab 121 and the post 140.

[0215] In some embodiments, as shown in Figures 5, 10, 11 and 12, the cover plate 131 is provided with a pressure relief mechanism 150. In the length direction of the insulating member 132, the projection of the pressure relief mechanism 150 on the insulating member 132 is spaced apart from the through hole 1327. The fixing post 1321 includes a first fixing post 13213, which is located between the through hole 1327 and the projection of the pressure relief mechanism 150 on the insulating member 132. The first fixing post 13213 is offset from the pressure relief mechanism 150. By setting up a pressure relief mechanism 150, when the internal pressure of the battery cell 100 rises due to overcharging, over-discharging, overcurrent, or internal short circuit, the pressure relief mechanism 150 can automatically and quickly relieve the pressure of the battery cell 100, thereby preventing the battery cell 100 from exploding to a certain extent and improving the safety of the battery cell 100. By setting the projection of the pressure relief mechanism 150 on the insulating member 132 at intervals with the through hole 1327, the pressure relief mechanism 150 can avoid interfering with the connection between the tab 121 and the terminal post 140 to a certain extent, further reducing the connection difficulty between the tab 121 and the terminal post 140.

[0216] Meanwhile, by placing the first fixing post 13213 between the through hole 1327 and the projection of the pressure relief mechanism 150 on the insulating member 132, the first fixing post 13213 can be placed close to the pressure relief mechanism 150, thereby making the connection point between the first fixing post 13213 and the cover plate 131 close to the pressure relief mechanism 150. This facilitates strengthening the connection strength between the cover plate 131 and the insulating member 132 on the outer periphery of the pressure relief mechanism 150, thereby strengthening the structural strength of the cover plate 131 on the outer periphery of the pressure relief mechanism 150. This allows the pressure relief mechanism 150 to be stably placed on the cover plate 131, ensuring the working performance of the pressure relief mechanism 150 to a certain extent.

[0217] Furthermore, the first fixing post 13213 is staggered from the pressure relief mechanism 150. This can be understood as the first fixing post 13213 and the pressure relief mechanism 150 not being directly opposite each other in the thickness direction of the cover plate assembly 130. This avoids, to some extent, the pressure relief mechanism 150 being affected during the heat fusion process of the first fixing post 13213, such as causing the pressure relief mechanism 150 to break itself or causing the connection between the pressure relief mechanism 150 and the cover plate 131 to break, thereby avoiding affecting the performance of the pressure relief mechanism 150.

[0218] In some embodiments, the pressure relief mechanism 150 is an explosion-proof plate. When an abnormality occurs in the battery cell 100, causing an increase in air pressure, the explosion-proof plate breaks to allow the air pressure to be released through the cover plate 131, thereby achieving the purpose of pressure relief and improving the safety of the battery cell 100 in use.

[0219] In some embodiments, as shown in FIG12, the minimum distance between the projection of the fixing post 1321 onto the cover plate 131 and the pressure relief mechanism 150 is E, where 50mm ≥ E ≥ 17mm. This ensures that the minimum distance between the connection point of the fixing post 1321 and the cover plate 131 and the pressure relief mechanism 150 satisfies the condition of 17mm to 50mm. When the minimum distance between the connection point of the fixing post 1321 and the cover plate 131 and the pressure relief mechanism 150 is small, the distance between the connection point and the pressure relief mechanism 150 will be too close. This can easily affect the pressure relief mechanism 150 during the heat fusion process of the fixing post 1321, such as causing the pressure relief mechanism 150 to break itself or causing a break at the connection between the pressure relief mechanism 150 and the cover plate 131, thus affecting the performance of the pressure relief mechanism 150. Conversely, when the minimum distance between the connection point of the fixing post 1321 and the cover plate 131 and the pressure relief mechanism 150 is large, it will affect the fixing effect of the fixing post 1321.

[0220] Based on this, the minimum distance E between the projection of the fixing post 1321 onto the cover plate 131 and the pressure relief mechanism 150 is set to 50mm ≥ E ≥ 17mm. This is to a certain extent to avoid the pressure relief mechanism 150 from breaking or the connection between the pressure relief mechanism 150 and the cover plate 131 from breaking when the cover plate 131 and the insulating component 132 are connected by the fixing post 1321. This ensures the performance of the pressure relief mechanism 150 to a certain extent, and also allows the fixing post 1321 to be used to achieve a fixed connection between the cover plate 131 and the insulating component 132.

[0221] In some embodiments, the minimum distance E between the projection of the fixing post 1321 onto the cover plate 131 and the pressure relief mechanism 150 is 17mm, 18mm, 19mm, 20mm, 30mm, 40mm, or 50mm, etc.

[0222] In some embodiments, the minimum distance E between the projection of the fixing post 1321 onto the cover plate 131 and the pressure relief mechanism 150 satisfies: 17mm ≤ E ≤ 20mm. This avoids a large distance between the fixing post 1321 and the pressure relief mechanism 150, allowing multiple fixing posts 1321 to be positioned close to the pressure relief mechanism 150. This strengthens the connection between the cover plate 131 and the insulating member 132, increases the structural strength of the cover plate 131 near the pressure relief mechanism 150, and improves the structural stability of the cover plate 131, thereby enhancing the positional stability of the pressure relief mechanism 150.

[0223] Of course, in some embodiments, when the pressure relief mechanism 150 is located on the housing 110, since the pressure relief mechanism 150 is far from the fixing post 1321, the fixing post 1321 is not easily damaged during the hot melting process. Therefore, the minimum distance between the projection of the fixing post 1321 on the housing 110 and the pressure relief mechanism 150 can also be less than 17mm, and no specific limitation is made here.

[0224] In some embodiments, as shown in Figures 12 and 13, a plurality of first fixing posts 13213 are distributed on opposite sides of the pressure relief mechanism 150 along the length of the insulating member 132. This strengthens the connection between the cover plate 131 and the insulating member 132, and also enhances the connection between the cover plate 131 and the insulating member 132 near the pressure relief mechanism 150. This strengthens the structural strength of the cover plate 131 near the pressure relief mechanism 150, improves its structural stability, and thus enhances the positional stability of the pressure relief mechanism 150, thereby ensuring its performance to a certain extent.

[0225] In some embodiments, as shown in FIG12, a plurality of first fixing posts 13213 located on the same side of the pressure relief mechanism 150 are arranged at intervals along the length and / or width direction of the insulating member 132. This achieves a large number of first fixing posts 13213 distributed on opposite sides of the pressure relief mechanism 150, effectively strengthening the connection strength between the cover plate 131 near the pressure relief mechanism 150 and the insulating member 132.

[0226] Of course, in some other embodiments, as shown in FIG13, the multiple first fixing posts 13213 located on the same side of the pressure relief mechanism 150 may also be arranged at intervals along the width direction of the insulating member 132, thereby reducing the molding difficulty of the first fixing posts 13213.

[0227] In some embodiments, as shown in FIG12, the distance between two adjacent first fixing posts 13213 located on the same side of the pressure relief mechanism 150 along the length direction of the insulating member 132 is C, where 50mm ≥ C ≥ 13mm. This can, to a certain extent, avoid the adjacent first fixing posts 13213 being too close or too far apart. When the adjacent first fixing posts 13213 are too close, there is a problem of mutual interference during the connection process, increasing the manufacturing difficulty of the first fixing posts 13213; when the adjacent first fixing posts 13213 are too far apart, it affects the fixing effect of the cover plate 131 and the insulating member 132.

[0228] Therefore, the spacing C between two adjacent first fixing posts 13213 on the same side of the pressure relief mechanism 150 along the length of the insulating member 132 is set to satisfy: 50mm ≥ C ≥ 13mm. This reduces the manufacturing difficulty of the first fixing posts 13213 and also avoids mutual interference during connection to a certain extent. On the one hand, it reduces the connection difficulty between the cover plate 131 and the insulating member 132; on the other hand, it improves the performance of the first fixing posts 13213, enabling a stable connection between the cover plate 131 and the insulating member 132 using the first fixing posts 13213.

[0229] Optionally, the distance C between two adjacent first fixing posts 13213 on the same side of the pressure relief mechanism 150 along the length of the insulating member 132 is 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 30mm, 40mm or 50mm, etc.

[0230] In some embodiments, as shown in FIG12, the spacing C between two adjacent second fixing posts 13214 in the width direction of the insulating member 132 is 50mm ≥ C ≥ 13mm. This can, to a certain extent, avoid the adjacent second fixing posts 13214 being too close or too far apart. When the adjacent second fixing posts 13214 are too close, there is a problem of mutual interference between the adjacent second fixing posts 13214 during the connection process, increasing the manufacturing difficulty of the second fixing posts 13214; when the adjacent second fixing posts 13214 are too far apart, it affects the fixing effect of the cover plate 131 and the insulating member 132.

[0231] Therefore, the spacing C between two adjacent second fixing posts 13214 in the width direction of the insulating component 132 is set to satisfy: 50mm ≥ C ≥ 13mm. This reduces the manufacturing difficulty of the second fixing posts 13214 and also avoids mutual interference during connection to a certain extent. On the one hand, it reduces the connection difficulty between the cover plate 131 and the insulating component 132; on the other hand, it improves the performance of the second fixing posts 13214, enabling a stable connection between the cover plate 131 and the insulating component 132 using the second fixing posts 13214.

[0232] In a specific example, the spacing C between two adjacent second fixing posts 13214 in the width direction of the insulating member 132 is 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 30mm, 40mm or 50mm, etc.

[0233] In some embodiments, as shown in Figures 5, 6, and 13, a portion of the insulating member 132 is recessed toward the electrode assembly 120 to define a recess 1326. A hollowed-out area 1325 is provided within the recess 1326, and a pressure relief mechanism 150 is correspondingly disposed with respect to the hollowed-out area 1325. The hollowed-out area 1325 facilitates communication between the pressure relief mechanism 150 and the side of the insulating member 132 away from the cover plate 131. This ensures that when the internal pressure of the battery cell 100 rises due to overcharging, over-discharging, overcurrent, or internal short circuit, the pressure relief mechanism 150 can effectively and quickly relieve the pressure of the battery cell 100, thereby improving the safety of the battery cell 100.

[0234] In some embodiments, at least a portion of the pressure relief mechanism 150 is located within the settling tank 1326. While protecting the pressure relief mechanism 150 using the settling tank 1326, it also allows the pressure relief mechanism 150 to be positioned close to the electrode assembly 120, improving the explosion-proof performance of the pressure relief mechanism 150. Furthermore, the settling tank 1326 also serves to avoid the pressure relief mechanism 150, enabling the pressure relief mechanism 150 to effectively overturn and release air when subjected to external pressure.

[0235] In some embodiments, as shown in Figures 12 and 13, a through hole is provided in the sink 1326, and the through hole is formed as a hollow area 1325 to reduce the molding difficulty of the hollow area 1325.

[0236] In some embodiments, as shown in Figures 12 and 13, a plurality of fixing posts 1321 are arranged around the sink 1326 so that the connection points of the plurality of fixing posts 1321 and the cover plate 131 can be arranged close to the pressure relief mechanism 150. This not only strengthens the connection strength between the cover plate 131 and the insulating member 132, but also facilitates the increase of the structural strength of the cover plate 131 close to the pressure relief mechanism 150, thereby improving the structural stability of the cover plate 131 and thus improving the positional stability of the pressure relief mechanism 150.

[0237] In some embodiments, as shown in FIG5, the battery cell 100 further includes an insulating film 122, which wraps around the outer periphery of the electrode assembly 120. An insulating member 132 is fixedly connected to the insulating film 122 (the fixed connection point between the insulating member 132 and the insulating film 122 can be understood as the position shown by reference numeral 160 in FIG17). By wrapping the electrode assembly 122 around its outer periphery, the insulating film 122 isolates the electrode assembly 120 from the outer casing 110, thereby protecting the electrode assembly 120, extending its service life, and improving its safety.

[0238] Meanwhile, by fixing the insulating component 132 to the insulating film 122, the insulating component 132 and the electrode assembly 120 are fixedly connected, and the difficulty of fixing the insulating component 132 and the electrode assembly 120 is reduced. This allows the insulating component 132 to be stably placed between the cover plate 131 and the electrode assembly 120, thus ensuring the working performance of the insulating component 132 to a certain extent.

[0239] The schematic diagram of the fixed connection between the insulating component 132 and the insulating film 122 can be seen in Figures 15-18. The fixed connection between the insulating component 132 and the insulating film 122 can be achieved by heat fusion or snap-fitting.

[0240] In summary, the side of the insulating component 132 facing the cover plate 131 is thermally fixed to the cover plate 131 via a fixing post 1321, thereby fixing the insulating component 132 between the cover plate 131 and the electrode assembly 120. The side of the insulating component 132 is fixedly connected to the insulating film 122, so that the insulating film 122 wraps around the electrode assembly 120.

[0241] In some embodiments, as shown in Figures 5, 15, 16, and 17, an insulating film 122 is sleeved on the outer periphery of the electrode assembly 120. Firstly, the insulating film 122 facilitates the protection of the electrode assembly 120, preventing it from being subjected to external physical and chemical damage, such as scratches and corrosion, thereby extending its service life. Secondly, it isolates the positive and negative electrodes of the electrode assembly 120, preventing short circuits caused by direct contact between electrodes or external factors (such as metal debris or moisture), thus ensuring the safe operation of the battery cell 100 and improving its safety. Thirdly, it supports the electrode assembly 120, reducing its weight and preventing the tabs 121 from being stretched, extending their service life and allowing them to effectively perform their function.

[0242] In some embodiments, as shown in Figures 12, 15, 16, and 17, the fixed position between the insulating member 132 and the insulating film 122 is defined as the first fixed point 160. The distance between the projection of the first fixed point 160 on the insulating member 132 and the second fixed post 13214 is less than the distance between the second fixed post 13214 and the first fixed post 13213. That is, the second fixed post 13214 between the insulating member 132 and the cover plate 131 is set close to the fixed position between the insulating member 132 and the insulating film 122. In this way, when the battery cell 100 is subjected to external force, the force can be transmitted sequentially along the second fixed post 13214 and the electrode assembly 120, thereby avoiding excessive stress concentration or dispersion at the connection between the cover plate 131 and the insulating member 132 to a certain extent, and extending the service life of the battery cell 100.

[0243] Through the above settings, in a specific example, in order to achieve a stable connection between the cover plate 131 and the insulating component 132, the number n of the fixing posts 1321, the weight M of the electrode assembly 120, and the tensile force that a single fixing post 1321 can withstand are set to satisfy: n≥KM / (FS). In addition to satisfying the above relationship, the arrangement of the multiple fixing posts 1321 also needs to satisfy: multiple fixing posts 1321 are provided at both ends of the insulating component 132 along its length, and the multiple fixing posts 1321 are arranged along the width of the insulating component 132. The minimum distance B between the fixing posts 1321 and the first side 1323 satisfies: : 6mm≤B≤10mm; Multiple fixed posts 1321 are provided on opposite sides of the projection of the pressure relief mechanism 150 onto the insulating member 132. The multiple fixed posts 1321 are arranged along the width direction of the insulating member 132 or along the width and length direction of the insulating member 132. The minimum distance E between the projection of the fixed posts 1321 onto the cover plate 131 and the pressure relief mechanism 150 satisfies: 0mm≥E≥17mm. The distance C between adjacent fixed posts 1321 satisfies: 50mm≥C≥13mm. The minimum distance A between the fixed posts 1321 and the second side 1324 satisfies: 4mm≤A≤6mm.

[0244] In some embodiments, the capacity of the battery cell 100 is greater than 400Ah.

[0245] The capacity of a single battery cell (100) can be obtained by testing as follows:

[0246] At 25°C, battery cell 100 is left to stand for 5 minutes, then discharged at a constant current of 0.33C to the lower cutoff voltage. After standing for 5 minutes, it is charged at a constant current of 0.33C to the upper cutoff voltage, and then charged at a constant voltage at the upper cutoff voltage until the current is 0.05C. After standing for 5 minutes, it is discharged at a constant current of 0.33C to the lower cutoff voltage. The discharge capacity at this time is recorded, which is the capacity of battery cell 100.

[0247] The upper and lower cutoff voltages can be the charge / discharge voltages recommended in the product specifications of the battery cell 100. For example, when the positive electrode active material includes lithium iron phosphate and the negative electrode active material includes graphite, the upper cutoff voltage of the battery cell 100 can be 3.65V and the lower cutoff voltage can be 2.5V.

[0248] In this embodiment, the battery cell 100's range is improved by limiting its rated capacity.

[0249] In some embodiments, the dimension W21 of the housing 110 in the first direction is greater than or equal to 80 mm and less than or equal to 300 mm; the dimension L21 of the housing 110 in the second direction is greater than or equal to 68 mm and less than or equal to 100 mm; the dimension H21 of the housing 110 in the third direction is greater than or equal to 205 mm and less than or equal to 250 mm; the first direction, the second direction, and the third direction intersect each other. W21, L21, and H21 are specifically referred to in Figure 5. It should be noted that the first direction can be the length direction of the housing 110, and in the square-shell form of the battery cell 100, the first direction can correspond to the width direction of the battery cell 100; the second direction can be the width direction of the housing 110, and in the square-shell form of the battery cell 100, the second direction can correspond to the thickness direction of the battery cell 100; the third direction can be the height direction of the housing 110, and in the square-shell form of the battery cell 100, the third direction can correspond to the height direction of the battery cell 100.

[0250] The dimension W21 of the housing 110 in the first direction can be 80mm, 85mm, 90mm, 100mm, 150mm, 200mm, 260mm, or 300mm, etc. The dimension L21 of the housing 110 in the second direction can be 68mm, 70mm, 72mm, 75mm, 80mm, 85mm, 90mm, or 100mm, etc. The dimension H21 of the housing 110 in the third direction can be 205mm, 207mm, 210mm, 215mm, 220mm, 230mm, 240mm, or 250mm, etc.

[0251] In this embodiment, by limiting the dimensions of the outer casing 110 in the first direction, the second direction, and the third direction, the outer casing 110 can be adapted to a large-sized battery cell 100.

[0252] In some embodiments, as shown in FIG25, a groove 1111 is provided on the inner periphery of the opening 111, and the end of the cover plate 131 is accommodated in the groove 1111 and welded to the outer shell 110 to achieve a fixed connection between the cover plate 131 and the outer shell 110.

[0253] In a specific example, cover plate 131 is welded to housing 110 via a top weld.

[0254] In some embodiments, as shown in Figures 26 and 27, the cover plate 131 overlaps the end of the housing 110 and is welded to the housing 110 to achieve a fixed connection between the cover plate 131 and the housing 110.

[0255] In a specific example, the cover plate 131 is welded to the housing 110 via side welding.

[0256] In some embodiments, as shown in Figures 26 and 27, the outer periphery of the cover plate 131 is provided with an overlapping protrusion 1312, which overlaps the end of the outer shell 110 and is welded to the outer shell 110 to achieve a fixed connection between the cover plate 131 and the outer shell 110.

[0257] The battery device 200 of this application according to the present invention will now be described with reference to the accompanying drawings.

[0258] As shown in FIG3, the battery device 200 of this application embodiment includes the battery cell 100 of the above embodiment.

[0259] Since the battery cell 100 of this application embodiment has the above-mentioned technical effects, the battery device 200 of this application embodiment also has the above-mentioned technical effects, that is, by adopting the battery cell 100 of this application, the working performance of the battery device 200 is improved.

[0260] The energy storage device 300 of this application is described below with reference to the accompanying drawings.

[0261] As shown in Figure 2, the energy storage device 300 of this application embodiment includes a plurality of battery cells 100 or a plurality of battery devices 200 of the above embodiments, wherein the battery cells 100 or battery devices 200 are used to store or provide electrical energy.

[0262] Since the battery cell 100 or battery device 200 of the present application embodiment has the above-mentioned technical effects, the energy storage device 300 of the present application embodiment also has the above-mentioned technical effects, that is, by adopting the battery cell 100 or battery device 200 of the present application, the working performance of the energy storage device 300 is improved.

[0263] The electrical device 1000 of this application is described below with reference to the accompanying drawings.

[0264] As shown in Figure 1, the power-consuming device 1000 of this application embodiment includes the battery cell 100, the battery device 200, or the energy storage device 300 of the above embodiments. The battery cell 100 or the battery device 200 is used to store or provide electrical energy.

[0265] Since the battery cell 100, battery device 200 or energy storage device 300 of the present application embodiments have the above-mentioned technical effects, the power consumption device 1000 of the present application embodiments also has the above-mentioned technical effects, that is, by adopting the battery cell 100, battery device 200 or energy storage device 300 of the present application, the working performance of the power consumption device 1000 is improved.

[0266] It is understood that other configurations of the battery cell 100, battery device 200, energy storage device 300, and power consumption device 1000 according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.

[0267] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0268] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell (100), wherein include: The outer casing (110) has an opening (111) at one end; An electrode assembly (120) is disposed within the housing (110), and the electrode assembly (120) is provided with tabs (121); A cover plate assembly (130) is disposed on the housing (110) to cover the opening (111). The cover plate assembly (130) includes a cover plate (131) and an insulating member (132). The cover plate (131) has an electrode post (140) electrically connected to the electrode tab (121). The insulating member (132) is located between the cover plate (131) and the electrode assembly (120). The cover plate (131) has at least one fixing hole (1311), and the insulating member (132) has a connection to the fixing hole (1311). At least one fixing post (1321) is provided to fix the cover plate (131) and the insulating member (132) together. The fixing post (1321) includes a first part (13211) and a second part (13212) that are connected to each other. The first part (13211) is located in the fixing hole (1311), and the second part (13212) is located on the side of the first part (13211) away from the insulating member (132). The cross-sectional area of ​​the second part (13212) is larger than the cross-sectional area of ​​the first part (13211). The cover plate assembly (130) is configured to satisfy: n ≥ KM / (FS), where n is the number of the fixing posts (1321); M is the weight of the electrode assembly (120), the unit of M is N, and the value of M is 50N ≤ M ≤ 120N; S is the cross-sectional area of ​​a single first portion (13211), the unit of S is mm. 2 The value of K ranges from 5 to 9; the unit of F is N / mm. 2 The value of F ranges from 15 N / mm. 2 ≤F≤25N / mm 2 .

2. The battery cell (100) according to claim 1, wherein The first portion (13211) is cylindrical, S = π(D / 2) 2 where D is the diameter of the first portion (13211) in mm.

3. The battery cell (100) according to claim 2, wherein 4≤n≤22, D≥2mm.

4. The battery cell (100) according to claim 2 or 3, wherein 2.5mm≤D≤5mm.

5. The battery cell (100) according to any one of claims 1-4, wherein, 10≤n≤14。 6. The battery cell (100) according to any one of claims 1-5, wherein, The fixing hole (1311) includes a first fixing hole (13111) and a second fixing hole (13112) that are interconnected. The first fixing hole (13111) opens toward the insulating member (132). The second fixing hole (13112) is located on the side of the first fixing hole (13111) away from the insulating member (132). At least a portion of the diameter of the second fixing hole (13112) is larger than the diameter of the first fixing hole (13111). The first portion (13211) is located inside the first fixing hole (13111), and the second portion (13212) is located inside the second fixing hole (13112). The fixing post (1321) is a plastic part.

7. The battery cell (100) according to any one of claims 1-6, wherein, There are multiple fixing posts (1321), some of which are spaced apart along the length direction of the insulating member (132), and some of which are spaced apart along the width direction of the insulating member (132).

8. The battery cell (100) according to claim 7, wherein The plurality of fixing posts (1321) spaced apart along the length of the insulating member (132) are symmetrically arranged along a straight line containing the midpoint of the insulating member (132) along its length; and / or, The plurality of fixing posts (1321) spaced apart in the width direction of the insulating member (132) are symmetrically arranged along the straight line where the midpoint of the insulating member (132) is located in the width direction.

9. The battery cell (100) according to any one of claims 1-8, wherein, The insulating member (132) is provided with two through holes (1327) spaced apart along its length. The electrode tab (121) includes a positive electrode tab and a negative electrode tab. The electrode post (140) includes a positive electrode post and a negative electrode post. The positive electrode tab and the positive electrode post are electrically connected through one of the through holes (1327). The negative electrode tab and the negative electrode post are electrically connected through the other through hole (1327). Along the length of the insulating member (132), the insulating member (132) has a first side (1323) disposed opposite to each other. There are multiple fixing posts (1321), at least some of the fixing posts (1321) are disposed between two through holes (1327) to form a first fixing post (13213), and at least some of the fixing posts (1321) are disposed between the through hole (1327) and the first side (1323) to form a second fixing post (13214).

10. The battery cell (100) of claim 9, wherein, The end of the insulating member (132) in the length direction is provided with a support boss (1322) protruding toward the electrode assembly (120), the support boss (1322) being adapted to support the electrode assembly (120), wherein, in the thickness direction of the cover plate (131), the second fixing post (13214) is disposed opposite to the support boss (1322).

11. The battery cell (100) according to claim 9 or 10, wherein The fixing post (1321) further includes a third fixing post (13215), which is located between the through hole (1327) and the second fixing post (13214).

12. The battery cell (100) according to any one of claims 1-11, wherein, Along the length of the insulating member (132), the insulating member (132) has a first side (1323) disposed opposite to it, and the minimum distance B between the fixing post (1321) and the first side (1323) satisfies: 6mm ≤ B ≤ 10mm; and / or, In the width direction of the insulating member (132), the insulating member (132) has a second side (1324) arranged opposite to it, and the minimum distance A between the fixing post (1321) and the second side (1324) satisfies: 4mm≤A≤6mm.

13. The battery cell (100) according to any one of claims 1-12, wherein, The insulating component (132) is provided with a through hole (1327), and the electrode tab (121) and the electrode post (140) are electrically connected through the through hole (1327); The cover plate (131) is provided with a pressure relief mechanism (150). In the length direction of the insulating member (132), the projection of the pressure relief mechanism (150) on the insulating member (132) is spaced apart from the through hole (1327). The fixing post (1321) includes a first fixing post (13213). The first fixing post (13213) is located between the through hole (1327) and the projection of the pressure relief mechanism (150) on the insulating member (132). The first fixing post (13213) is staggered from the pressure relief mechanism (150).

14. The battery cell (100) according to claim 13, wherein The minimum distance between the projection of the fixed column (1321) on the cover plate (131) and the pressure relief mechanism (150) is E, 50mm≥E≥17mm.

15. The battery cell (100) according to claim 13 or 14, wherein Along the length of the insulating member (132), a plurality of first fixing posts (13213) are distributed on both sides of the pressure relief mechanism (150).

16. The battery cell (100) according to claim 15, wherein A plurality of first fixing posts (13213) located on the same side of the pressure relief mechanism (150) are arranged at intervals along the length and / or width of the insulating member (132).

17. The battery cell (100) according to claim 16, wherein The distance between two adjacent first fixing posts (13213) located on the same side of the pressure relief mechanism (150) in the length direction of the insulating member (132) is C, 50mm≥C≥13mm.

18. The battery cell (100) according to any one of claims 13-17, wherein, A portion of the insulating member (132) is recessed toward the electrode assembly (120) to define a recess (1326), the recess (1326) having a hollow area (1325), and the pressure relief mechanism (150) being provided correspondingly to the hollow area (1325).

19. The battery cell (100) according to any one of claims 1-18, wherein, It also includes an insulating film (122) that wraps around the outer periphery of the electrode assembly (120), and the insulating element (132) is fixedly connected to the insulating film (122).

20. The battery cell (100) according to any one of claims 1-19, wherein, The capacity of the battery cell (100) is greater than 400Ah.

21. The battery cell (100) according to any one of claims 1-20, wherein, The outer casing (110) has a dimension in the first direction that is greater than or equal to 80 mm and less than or equal to 300 mm; The outer casing (110) has a dimension in the second direction that is greater than or equal to 68 mm and less than or equal to 100 mm; The outer casing (110) has a dimension in the third direction that is greater than or equal to 205 mm and less than or equal to 250 mm; The first direction, the second direction, and the third direction intersect each other.

22. The battery cell (100) according to any one of claims 1-21, wherein, The inner periphery of the opening (111) is provided with a recess (1111), and the end of the cover plate (131) is accommodated in the recess (1111) and welded to the outer shell (110).

23. The battery cell (100) according to any one of claims 1-22, wherein, The cover plate (131) overlaps the end of the outer shell (110) and is welded to the outer shell (110).

24. A battery device (200), wherein, Includes the battery cell (100) according to any one of claims 1-23.

25. An energy storage device (300), wherein, It includes a plurality of battery cells (100) according to any one of claims 1-23 or a plurality of battery devices (200) according to claim 24, wherein the battery cells (100) or the battery devices (200) are used to store or provide electrical energy.

26. An electrically powered device (1000), wherein Includes a battery cell (100) according to any one of claims 1-23, a battery device (200) according to claim 24, or an energy storage device (300) according to claim 25, wherein the battery cell (100) or the battery device (200) is used to store or provide electrical energy.

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