Battery packs and electrical devices

Abstract

We provide battery packs with improved energy density. [Solution] The present invention relates to a battery pack and electrical device comprising a housing having a bottom cover (12) that surrounds and forms a housing cavity (s) and is located at the bottom of the housing to define the housing cavity (s), and a battery cell (20) housed within the housing cavity (s). Here, the bottom cover (12) has a feature surface facing the housing cavity (s), and the feature surface is configured as a plane.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to battery packs and electrical devices.

Background Art

[0002] With the development of new energy technologies, new energy vehicles have gradually come into people's view. The main core technology of new energy vehicles lies in the battery pack, and the safety and stability of the battery pack directly determine the performance of the entire vehicle.

[0003] The endurance of the battery pack is a focus of concern in the field of new energy vehicles. Since the current endurance of the battery pack is generally not high, improving the endurance of the battery pack is an urgent issue to be solved.

Summary of the Invention

[0004] In view of this, this application provides a battery pack and an electrical device.

[0005] In a first aspect, this application provides a battery pack including a housing that surrounds to form a receiving cavity and has a bottom cover located at its bottom to define the receiving cavity, and battery cells housed in the receiving cavity. The bottom cover has a characteristic surface facing the receiving cavity, and the characteristic surface is configured as a flat surface.

[0006] In the technical solution of this application, when the characteristic surface is a flat surface, the characteristic surface can maintain a relatively uniform distance (this distance may be 0) from each battery cell housed in the receiving cavity. When the distance between the characteristic surface and the battery cells is maintained relatively uniformly, more battery cells can be housed in the receiving cavity. That is, the space utilization rate of the receiving cavity is higher, the battery pack can have a higher energy density, and the endurance of the battery pack is higher.

[0007] In some embodiments, the orthographic area S1 of the feature surface and the orthographic area S2 of the bottom cover satisfy S1 / S2 ≥ 0.2. In this case, the battery pack has a high energy density and good range.

[0008] In some embodiments, the orthogonal projection of the feature plane in the vertical direction is rectangular. In this case, more battery cells can be placed within the housing cavity, improving the energy density of the battery pack.

[0009] In some embodiments, the bottom cover has a lid portion for defining the housing cavity and a mounting portion connected to surround the edge of the lid portion and attached to the portion of the housing other than the lid portion. The inner surface structure of the lid portion facing the housing cavity forms the characteristic surface. In this case, the bottom cover defines the housing cavity via the lid portion and connects to the main body via the mounting portion, resulting in a clear structure and convenient installation.

[0010] In some embodiments, the outer surface of the lid away from the housing cavity is parallel to the feature surface. In this case, the lid with a flat outer surface significantly reduces wind resistance due to the battery pack, contributing to a reduction in the vehicle's running resistance, thereby reducing the energy consumption of the vehicle and improving the battery pack's range.

[0011] In some embodiments, the lid portion protrudes away from the housing cavity relative to the mounting portion. In this case, when the lid portion protrudes relative to the mounting portion, the lid portion of the bottom lid acts as a reinforcing structure for the bottom lid, thereby increasing the bending resistance of the bottom lid.

[0012] In some embodiments, the thickness of the lid is equal to the thickness of the mounting portion. In this case, the structure of the bottom lid becomes simpler and easier to manufacture.

[0013] In some embodiments, the bottom cover is spaced apart from the battery cells. In this case, it is possible to avoid external forces acting on the bottom cover being transmitted to the battery cells and damaging them. In particular, when the battery pack is mounted on the bottom of the vehicle and the bottom cover is located at the lowest part of the battery pack, stones and other objects from the ground are likely to fly onto the bottom of the battery pack and hit the bottom cover while the vehicle is in motion. In this case, the buffer space can block the effect of external forces transmitted to the battery cells on the battery cells.

[0014] In some embodiments, the housing further includes a support member located at its top to define a housing cavity, and the battery cells are suspended from the support member. In this case, the battery cells are suspended below the support member, and the bottom cover is located at the bottom of the housing. When repairing the inside of the battery pack, the battery cells can be exposed by removing the bottom cover without removing the support member. At the same time, when repairing the battery pack, the battery cells can be attached to and detached from the support member from below. In particular, if the support member is subjected to forces as at least part of the vehicle chassis, the battery cells can be attached to and detached from the support member from below without removing the support member, thus facilitating repair of the battery pack. Furthermore, the battery cells suspended from the support member can reinforce the strength of the support member, further improving the rigidity of the top of the battery pack.

[0015] In some embodiments, the outer surface of the battery cell facing the outer surface of the support member is the first outer surface, and the battery cell includes electrode terminals located on the outer surface other than the first outer surface of the battery cell. In this case, the electrode terminals are located on the outer surface other than the first outer surface of the battery cell, and various components connected to each electrode terminal (e.g., sampling wire harness, high-voltage wire harness, shielding structure, etc.) can be arranged through the space between the battery cell and the bottom cover and / or the space between the battery cell and the inner surface of the main body, making the arrangement of each component easier. In this case, by connecting the first outer surface without electrode terminals to the support member, it becomes possible to bond the battery cell and the support member, saving space between the battery cell and the support member and improving the space utilization efficiency of the battery pack.

[0016] In some embodiments, the battery cell has a second outer surface positioned opposite a first outer surface, and the electrode terminals are located on the second outer surface. In this case, a buffer space is formed between the second outer surface and the bottom cover, and the portion of the electrode terminals protruding from the battery cell is located within this buffer space, so that the wire harness and connecting sheet connected to the electrode terminals can be placed within the buffer space. At the same time, the buffer space can also block external forces hitting the bottom cover from acting on the battery cell and damaging it. Therefore, the buffer space not only blocks the effects of external forces but also allows for the routing of wire harnesses and the like, thus killing two birds with one stone.

[0017] In some embodiments, the battery cells are bonded to the support members. This not only facilitates the connection between the battery cells and the support members, but also simplifies the structure of the battery pack.

[0018] In some embodiments, the main body comprises a frame and support members, the frame enclosing a cavity that penetrates through both vertical ends, the bottom cover and support members fitting onto the opposing vertical ends of the cavity, and the bottom cover, frame, and support members jointly enclose a housing cavity. In this case, by using the frame as a base and connecting the support members and bottom cover to the vertical ends of the frame, a housing cavity for the battery pack can be formed, resulting in a simple housing structure.

[0019] In some embodiments, the support members are fixedly connected to or integrally molded with the frame. When the support members and frame are integrally molded, and the main body is integrally molded, the assembly of the housing can be achieved simply by connecting the main body to the bottom cover, making the assembly of the housing easy. When the support members are fixedly connected to the frame, the molding process for the support members and frame is relatively easy, which can reduce the manufacturing cost of the housing.

[0020] In a second aspect, the present invention further provides an electrical device comprising the battery pack, wherein the battery pack is used to supply electrical energy to the electrical device.

[0021] In some embodiments, the electrical device includes a vehicle, and the battery pack is located at the bottom of the vehicle body. In this case, because the battery pack is located at the bottom of the vehicle body, it does not occupy space inside the vehicle body, contributing to a reduction in the volume and weight of the vehicle body.

[0022] In some embodiments, the main body includes a support member located at the top of the housing to define a housing cavity, and the battery pack is attached to the vehicle body via the support member. When the battery cells are provided on the support member, the structure formed by the battery cells and the support member is connected to the vehicle body, thereby improving the strength of the top of the battery pack and further improving the mounting strength of the battery pack.

[0023] In some embodiments, the support member is configured to form at least a portion of the vehicle chassis. In this case, the space previously occupied by the gap between the chassis and the battery pack can be contained within the battery pack, increasing the battery pack's capacity, improving the battery pack's energy, and further contributing to an improved vehicle range.

[0024] Details of one or more embodiments of the present application are described in the following drawings and description. Other features, purposes and advantages of the present application will be apparent from the specification, drawings and claims. [Brief explanation of the drawing]

[0025] By reading the detailed description of the following preferred embodiments, various other advantages and benefits will become apparent to those skilled in the art. The drawings are used solely for the purpose of illustrating preferred embodiments and should not be considered limiting to this application. The same reference numerals are used for identical parts throughout the drawings. The drawings are as follows:

[0026] [Figure 1]It is a schematic diagram of the structure of a vehicle according to some embodiments of the present application. [Figure 2] It is a schematic diagram of the structure of a battery cell according to some embodiments of the present application. [Figure 3] It is a schematic diagram of the structure of a battery pack according to some embodiments of the present application. [Figure 4] It is an exploded view of the structure of the battery pack shown in FIG. 3. [Figure 5] It is a schematic diagram of the structure of a bottom cover according to some embodiments of the present application. [Figure 6] It is a plan view of the bottom cover shown in FIG. 5. [Figure 7] It is a front view of the bottom cover shown in FIG. 5. [Figure 8] It is a schematic diagram of the structure of a bottom cover according to another some embodiments of the present application. [Figure 9] It is a cross-sectional view of the battery pack shown in FIG. 4. [Figure 10] It is a schematic diagram of the orthographic projection in the vertical direction of the bottom cover shown in FIG. 6. [Figure 11] It is a schematic diagram of the appearance of a battery cell according to some embodiments of the present application. [Figure 12] It is a front view of the battery cell shown in FIG. 11. [Figure 13] It is a schematic diagram of the structure of a support member according to some embodiments of the present application. [[ID=3Y]] [Figure 14] It is a schematic diagram of the structure of a support member according to another some embodiments of the present application. [Figure 15] It is an orthographic projection view in the vertical direction of the support member shown in FIG. 14. [Figure 16] It is a front view of the battery pack shown in FIG. 4. ​​​​​​​​​​​​​

[0027] 1000-Vehicle, 100-Battery pack, 200-Vehicle body, 10-Housing, 11-Main body, 11a-Support member, 11a1-Support part, 11a2-Connection part, 11b-Frame, 12-Bottom cover, 12a-Cover part, 12b-Mounting part, 12c-Fixing hole, 13-Fastener, s-Housing cavity, q-Cavity, f-Support surface, f1-First support edge, f2-Second support edge, f3-Third support edge, f4-Fourth support edge, d-Feature surface, d1-First feature edge, d2-Second feature edge, d3-Third feature edge, d4-Fourth feature edge, 20-Battery cell, 21-End cap, 21a-Electrode terminal, 22-Case, 23-Electrode assembly, m1-First outer surface, m2-Second outer surface, m3-Third outer surface. [Modes for carrying out the invention]

[0028] The following describes embodiments of the present application in detail with reference to the drawings. The following embodiments are merely illustrative and intended to more clearly illustrate the technical concept of the present application, and do not limit the scope of protection of the present application.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art. Terms used herein are solely for the purpose of describing specific embodiments and are not intended to limit this application. The terms “including” and “having,” and any variations thereof, in the description, claims, and brief description of the drawings herein, are intended to cover non-exclusive inclusion.

[0030] In the description of the embodiments of this application, technical terms such as "first," "second," etc., are used merely to distinguish different subjects and should not be understood as indicating relative importance or implying the number of technical features, a specific order, or a hierarchical relationship. In the description of the embodiments of this application, "plural" means two or more unless otherwise specified.

[0031] As used herein, “Examples” means that a combination of specific features, structures, or properties described in the Examples may be included in at least one Example of the Application. The term as it appears throughout this Specification does not necessarily refer to the same Example, nor does it mean that each Example is mutually exclusive, independent, or substitutable for another Example. Those skilled in the art will understand, both explicitly and implicitly, that the Examples described herein may be combined with other Examples.

[0032] In the description of the embodiments of this application, the term "and / or" merely describes the relationship between the related objects, meaning that there can be three possible relationships. For example, "A and / or B" could refer to just A, both A and B, or just B. In addition, the " / " in the text generally indicates that the preceding and following related objects have an "or" relationship.

[0033] In the description of the embodiments of this application, the term "multiple" means two or more (including two), similarly, "multiple sets" means two or more sets (including two sets), and "multiple sheets" means two or more sheets (including two sheets).

[0034] In the description of the embodiments of this application, the orientations and positional relationships indicated by technical terms such as "center," "vertical direction," "horizontal direction," "length," "width," "thickness," "top," "bottom," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," "clockwise," "counterclockwise," "axial direction," "radial direction," and "circumferential direction" are based on the orientations and positional relationships shown in the drawings and are merely for the purpose of facilitating and simplifying the description of the embodiments of this application. They do not indicate or imply that the shown devices or elements must have a specific orientation or must be configured and operate in a specific orientation, and therefore should not be interpreted as limiting the embodiments of this application.

[0035] In the description of the embodiments of this application, unless otherwise specified or limited, technical terms such as "attached," "connected," "connected," and "fixed" should be understood in a broad sense. For example, a fixed connection, a detachable connection, or a connection that may be integrally molded; a mechanical connection or an electrical connection; a direct connection or an indirect connection via an intermediate medium; or an internal communication between two elements or an interaction relationship between two elements. A person skilled in the art will be able to understand the specific meaning of these terms described in the embodiments of this application depending on the specific situation.

[0036] Currently, given the development of the market, the applications of battery packs are expanding more and more. Battery packs are used not only in energy storage and power generation systems such as hydroelectric power plants, thermal power plants, wind power plants, and solar power plants, but also in many other fields such as electric mobility tools such as electric bicycles, electric motorcycles, and electric vehicles, military equipment, and aerospace. As the application fields of battery packs continue to expand, their market demand is also growing.

[0037] The inventors of the present invention have noticed that the bottom cover of conventional battery pack housings is usually provided in a way that protrudes outward, for the purpose of preventing external forces that collide with the bottom cover from being transmitted to the battery cells through the bottom cover. However, the space occupied by this protruding bottom cover reduces the space utilization rate of the battery pack, further reducing the energy density of the battery pack and thus being detrimental to improving the range of the battery pack.

[0038] To improve the range of the battery pack, the applicant found through research that designing the bottom cover to be flat reduces the space occupied by the bottom cover itself within the housing cavity, allowing as much space as possible to be used for mounting the battery cells, thereby improving the energy density and range of the battery pack.

[0039] In view of the above, and in order to improve the safety and service life of the battery pack, the inventors have seriously considered and designed a battery pack comprising a housing that encloses a housing cavity and has a bottom cover located at its bottom to define the housing cavity, and battery cells housed within the housing cavity, wherein the bottom cover has a feature surface facing the housing cavity, and the feature surface is configured as a plane. When the feature surface is plane, the feature surface can maintain a relatively uniform distance (this distance may be 0) from each battery cell housed within the housing cavity. When the distance between the feature surface and the battery cells is maintained relatively uniformly, more battery cells can be housed in the housing cavity, that is, the space utilization rate of the housing cavity is higher, the battery pack can have a higher energy density, and the range of the battery pack is higher.

[0040] The battery pack according to the embodiment of the present application may be used in electrical devices such as vehicles, ships, or aircraft, but is not limited thereto. The battery pack according to the present application may also be used to form a power supply system for such electrical devices. The mounting body according to the present application is a structure for mounting the battery pack to an electrical device.

[0041] Embodiments of the present invention provide an electrical device powered by a battery pack. The electrical device may be, but is not limited to, a mobile phone, tablet, laptop computer, electric toy, power tool, electric bicycle, electric car, ship, or spacecraft. Here, electric toys may include stationary or mobile electric toys such as game consoles, electric car toys, electric boat toys, and electric airplane toys, and spacecraft may include airplanes, rockets, space shuttles, and spaceships.

[0042] In the following embodiments, for the sake of explanation, an embodiment of the present invention in which the electrical device is a vehicle 1000 will be used for description.

[0043] Referring to Figure 1, Figure 1 shows a schematic diagram of the structure of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a gasoline vehicle, a natural gas vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or a range-extender electric vehicle, etc. A battery pack 100 is provided inside the vehicle 1000, and the battery pack 100 may be located at the bottom, top, or rear of the vehicle 1000. The battery pack 100 can be used to power the vehicle 1000, for example, as the operating power source for the vehicle 1000. The vehicle 1000 may further include a controller and a motor for controlling the battery pack 100 to supply power to the motor for operating power demands, for example, when the vehicle 1000 is started, during navigation, or while driving.

[0044] In some embodiments of the present invention, the battery pack 100 can provide driving force to the vehicle 1000 not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, as a substitute or partial substitute for gasoline or natural gas.

[0045] Referring to Figure 2, which is a schematic diagram of the structure of a vehicle 1000 according to a partial embodiment of the present application, the battery cell 20 is the smallest unit constituting the battery pack 100. As shown in Figure 2, the battery cell 20 includes an end cap 21, a case 22, an electrode assembly 23, and other functional components.

[0046] The end cap 21 refers to a component that covers the opening of the case 22, sealing the internal environment of the battery cell 20 from the external environment. The shape of the end cap 21 can be, but is not limited to, that of the case 22 in order to fit the case 22. Selectively, the end cap 21 may be manufactured from a material having a certain degree of hardness and strength (e.g., aluminum alloy). In this way, the end cap 21 is less likely to deform even when subjected to pressure or impact, the battery cell 20 can have higher structural strength, and safety can also be improved. Functional components such as electrode terminals 21a may be provided on the end cap 21. Electrode terminals 21a can be used to electrically connect to the electrode assembly 23 in order to output or input electrical energy from the battery cell 20. In some embodiments, the end cap 21 may also be provided with a pressure release mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 may also be a variety of materials such as copper, iron, aluminum, stainless steel, aluminum alloy, and plastic, and is not particularly limited in the embodiments of this application. In some embodiments, an insulating member may be provided inside the end cap 21, which can be used to insulate the electrical connection members in the case 22 from the end cap 21 and reduce the risk of short circuits. Exemplarily, the insulating member may be made of plastic, rubber, or the like.

[0047] The case 22, together with the end cap 21, is a component for forming the internal environment of the battery cell 20. This formed internal environment can be used to house the electrode assembly 23, electrolyte, and other components. The case 22 and end cap 21 may be separate components, or the internal environment of the battery cell 20 may be formed by providing an opening in the case 22 and covering the opening with the end cap 21. Without limiting this, the end cap 21 and case 22 can also be integrated. Specifically, a common connection surface can be formed by the end cap 21 and case 22 before other components are placed inside the case, and if it is necessary to seal the inside of the case 22, the end cap 21 can be fitted onto the case 22. The case 22 may be of various shapes and sizes, such as a rectangular parallelepiped, cylindrical, or hexagonal shape. Specifically, the shape of the case 22 may be determined according to the specific shape and size of the electrode assembly 23. The material of the case 22 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, or plastic, and is not particularly limited in the embodiments of this application.

[0048] The electrode assembly 23 is a component in the battery cell 20 where an electrochemical reaction occurs. The case 22 may contain one or more electrode assemblies 23. The electrode assembly 23 is mainly formed by winding or overlapping a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive electrode sheet and the negative electrode sheet that have active material form the main body of the electrode assembly 23, and the portions of the positive electrode sheet and the negative electrode sheet that do not have active material form separate positive electrode tabs and negative electrode tabs. The positive electrode tabs and negative electrode tabs may both be located at one end of the main body or at both ends of the main body, respectively. During charging and discharging of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs are connected to the electrode terminals 21a to form an electric current circuit.

[0049] Figure 3 is a schematic diagram of the structure of a battery pack 100 according to a partial embodiment of the present application, and Figure 4 is an exploded view of the structure of the battery pack 100 shown in Figure 3. According to a partial embodiment of the present application, referring to Figures 3 and 4, the present embodiment provides a battery pack 100 comprising a battery cell 20 and a housing 10, the housing 10 forming a housing cavity s, and the battery cell 20 is housed in the housing cavity s.

[0050] In the battery pack 100, there may be multiple battery cells 20, and the multiple battery cells 20 can be connected in series, in parallel, or in series-parallel connection. Series-parallel connection means that not only are some of the multiple battery cells 20 connected in series, but some are also connected in parallel. The multiple battery cells 20 may be connected in series, in parallel, or in series-parallel connection, and then the entire assembly of the multiple battery cells 20 may be housed in the housing 10. Of course, the battery pack 100 may first form a battery module by connecting multiple battery cells 20 in series, in parallel, or in series-parallel connection, and then form a whole by connecting multiple battery modules in series, in parallel, or in series-parallel connection, and then housed in the housing 10. The battery pack 100 may also have other structures, for example, the battery pack 100 may further include busbar members for realizing electrical connections between the multiple battery cells 20. Here, each battery cell 20 may be a secondary battery or a primary battery, and may be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The shape of the battery cell 20 may be cylindrical, flattened, rectangular, or other shapes.

[0051] The housing 10 may have various shapes such as cylindrical or rectangular, and the specific structure of the housing 10 may employ various structural methods.

[0052] In some embodiments, referring again to Figures 3 and 4, the housing 10 includes a main body 11 and a bottom cover 12 provided at the bottom of the main body 11, and the bottom cover 12 and the main body 11 jointly enclose a housing cavity s for housing the battery cells 20.

[0053] The main body 11 may be a single-piece molded structure or it may be assembled from multiple parts. The main body 11 may be a hollow case 22 structure, which itself defines a first space, with the bottom of the first space being open, and the bottom cover 12 covers the opening of the first space. The bottom cover 12 may be a hollow structure with one side open, and may itself have a second space, and the second space of the bottom cover 12 and the first space of the main body 11 together form a housing cavity s. The bottom cover 12 itself does not have a space that forms the housing cavity s, and when the bottom cover 12 covers the opening of the first space of the main body 11, the bottom cover 12 seals the first space of the main body 11, and the two together surround it to form a housing cavity s corresponding to the first space, in which case the bottom cover 12 may be a flat plate structure. Of course, the housing cavity s of the housing 10 may be formed by a part of the first space of the main body 11, in which case the bottom cover 12 may fit over the opening of the first space and recess into the first space, occupying a part of the first space, and the first space excluding the portion occupied by the bottom cover 12 may form the housing cavity s of the housing 10.

[0054] To make it clear, in this case, the bottom cover 12 is located at the bottom of the housing 10 and is used together with the main body 11 to define the housing cavity s. Specifically, the bottom cover 12 may be a plate-like structure, a block-like structure, or it may be flat, curved, or the like, and is not particularly limited.

[0055] If the battery cell 20 is located in the housing cavity s, the battery cell 20 may be provided in the bottom cover 12 and / or the main body 11.

[0056] When the main body 11 is assembled from multiple parts, the battery cell 20 may be provided in one of the parts or in all of the parts. In one embodiment, the main body 11 may include a top cover (not shown), an enclosure plate (not shown), and a support plate (not shown), the enclosure plate enclosing a third space having openings at both vertical ends, the top cover and bottom cover 12 sealing the vertical ends of the third space, the top cover, enclosure plate, and bottom cover 12 jointly enclosing a housing cavity s, the support plate located within the third space, and the battery cell 20 being supported by the support plate. In other embodiments, the main body 11 may include a support member 11a and a frame 11b, which will be described in detail below.

[0057] The bottom cover 12 and the main body 11 may be fixed together by means of welding, heat welding, bonding, fastening, locking, etc. Here, fastening refers to achieving connection by fasteners 13, and fasteners 13 include parts such as bolts, pins, rivets, studs, and screws. Locking refers to achieving fixation by an engaging structure. For example, if the bottom cover 12 has a hook and the main body 11 has a bayonet, engaging the hook with the bayonet can achieve engagement and fixation between the bottom cover 12 and the main body 11. Of course, the connection method between the bottom cover 12 and the main body 11 is not limited to this and is not covered in this application.

[0058] In some embodiments, the bottom cover 12 and the main body 11 are sealed together to form a sealed containment cavity s.

[0059] There are various methods for sealing and connecting the bottom cover 12 and the main body 11. These include, but are not limited to, installing a sealing member between the bottom cover 12 and the main body 11 and sealing and connecting the bottom cover 12 and the main body 11 with the sealing member, sealing and connecting the bottom cover 12 and the main body 11 with a sealant, and connecting the bottom cover 12 and the main body 11 by inserting them into each other and sealing and connecting them with a sealing structure formed by the insertion connection surface.

[0060] In this case, the housing 10 of the battery pack 100 forms a sealed housing cavity s by surrounding its own bottom cover 12 and its own body 11. Therefore, there is no need to provide any other sealing structure separately inside the housing 10, which simplifies the structure of the battery pack 100, reduces the cost of the battery pack 100, and ensures the safety and service life of the battery pack 100.

[0061] In this description, the bottom cover 12 of the battery pack 100 is located at the bottom of the main body 11, that is, in the vertical direction shown in Figures 3 and 4, the bottom cover 12 is located at the bottom of the main body 11. In actual use, the vertical direction shown in Figures 3 and 4 may be the vertical direction, but is not limited to this, and will be determined according to the actual mounting situation of the battery pack 100. In the following description of this application, the positional relationships and dimensions of each structure of the battery pack 100 are based on the vertical direction, but this is not intended to limit the way the battery pack 100 is used, but merely to explain the technical proposal more clearly and concisely.

[0062] In some embodiments, the bottom cover 12 is sealed and connected to the main body 11 via a sealing member.

[0063] A sealing member refers to a component that prevents fluids, solid particles, etc., from leaking out from between adjacent joint surfaces, and prevents external impurities such as dust and moisture from entering the battery pack 100. The sealing connection between the main body 11 and the bottom cover 12 by a sealing member means that the sealing member is connected between two opposing surfaces of the main body 11 and the bottom cover 12, has a ring-shaped contact interface between the two surfaces, and prevents external moisture from entering the battery pack 100 through the contact cross-section between itself and the two surfaces, thereby achieving a sealing effect.

[0064] The sealing member may be a sealing ring or a gasket. Specifically, the sealing member may be made from a material such as rubber or silicone. Specifically, the sealing member can be an O-type seal, a square seal, or an irregularly shaped seal. The specific shape of the sealing member can be matched to the shapes of two opposing surfaces of the bottom cover 12 and the main body 11. For example, if the two opposing surfaces of the bottom cover 12 and the main body 11 are ring-shaped, the sealing member may be an O-type seal.

[0065] In this case, the bottom cover 12 achieves a sealed connection with the main body 11 via a sealing member, resulting in reliable sealing and low cost.

[0066] Furthermore, after the bottom cover 12 achieves a sealed connection with the main body 11 via a sealing member, it can be further fixedly connected to the main body 11 by other methods. Other methods include, but are not limited to, locking, push-in connection, screw connection, riveting, welding, and bonding. To understand this, when the bottom cover 12 is sealed to the main body 11 via a sealing material, depending on the adhesive properties of the sealing material, if the adhesive properties of the sealing material are good and meet the requirements (i.e., the bottom cover 12 and the main body 11 are fixed and do not separate), it may not be necessary to fix and connect them by other methods.

[0067] In some embodiments, the bottom cover 12 is detachably connected to the bottom of the main body 11.

[0068] The fact that the bottom cover 12 is detachably connected to the main body 11 means that when the bottom cover 12 is connected to the main body 11, it has a first state in which it is fully connected to the main body 11 and forms a housing cavity s, and a second state in which it is incompletely connected to or separated from the main body 11 and opens up to expose the battery cell 20, and the bottom cover 12 can be switched from the first state to the second state and from the second state to the first state by the operation of an external force, and in this process no parts are damaged.

[0069] If the bottom cover 12 has a second state in which it is incompletely connected to the main body 11 and opens the housing cavity s, the attachment of the bottom cover 12 to the main body 11 may be such that the bottom cover 12 is rotatably connected to the main body 11 and a fixed connection is achieved by fasteners 13 or an engagement mechanism. When the bottom cover 12 is rotated relative to the main body 11 until it closes the housing cavity s, the bottom cover 12 is fixedly connected to the main body 11 by fasteners 13 or an engagement mechanism, and the battery cell 20 is housed in the housing cavity s in a way that it is not visible, and at this time the bottom cover 12 is in the first state. When the fasteners 13 are removed or the engagement connection is released, the bottom cover 12 can be rotated relative to the main body 11 to a position that opens the housing cavity s and exposes the battery cell 20, and at this time the bottom cover 12 is in the second state. Here, the rotatable connection between the bottom cover 12 and the main body 11 may be, but is not limited to, a connection between the bottom cover 12 and the main body 11 via a pivot axis.

[0070] If the bottom cover 12 has a second state in which it is separated from the main body 11 and opens the housing cavity s, the attachment of the bottom cover 12 to the main body 11 may be such that the bottom cover 12 and the main body 11 are fixedly connected by fasteners 13 or by engagement alone. If fasteners 13 are attached to the bottom cover 12 and the main body 11, or if the bottom cover 12 is engaged with the engagement structure of the main body 11, the bottom cover 12 and the main body 11 achieve complete fixation and jointly form the housing cavity s, and the battery cell 20 is housed in the housing cavity s in a way that makes it invisible, at which point the bottom cover 12 is in the first state. If the fasteners 13 are removed or all engagement connections are released, the bottom cover 12 can be separated from the main body 11, and the battery cell 20 is further exposed, at which point the bottom cover 12 is in the second state.

[0071] When the bottom cover 12 is in the first state, it can form a housing cavity s with the main body 11 to protect the battery cells 20. When the bottom cover 12 is in the second state, the battery cells 20 are exposed, making it easier for employees to maintain or replace the battery cells 20.

[0072] In some embodiments, referring to FIG. 4, the bottom cover 12 and the main body 11 are detachably connected via a fastener 13.

[0073] The fastener 13 refers to a member that can fasten two or more parts (or members) as a whole, and may be a screw, bolt, rivet, pin, pin roll, welding pin, etc., but is not limited thereto.

[0074] In this case, the bottom cover 12 and the main body 11 are detachably connected via the fastener 13, which is not only convenient for detachment and attachment, but also has a simple structure and is economical.

[0075] FIG. 5 is a schematic structural view of the bottom cover 12 according to some embodiments of the present application, FIG. 6 is a plan view of the bottom cover 12 shown in FIG. 5, FIG. 7 is a front view of the bottom cover 12 shown in FIG. 5, and FIG. 8 is a schematic structural view of the bottom cover 12 according to another some embodiments of the present application.

[0076] In some embodiments, the minimum thickness h of the bottom cover 12 satisfies 0.2 mm < h < 20 mm.

[0077] The thickness of the bottom cover 12 refers to the distance between two vertical side surfaces of the bottom cover 12 in a vertical cross-section. The minimum thickness h of the bottom cover 12 is the shortest distance between two vertical side surfaces of the bottom cover 12. When the thickness of each part of the bottom cover 12 is uniform, the bottom cover 12 may exhibit a flat plate shape (shown in FIG. 8), and the minimum thickness of the bottom cover 12 is the equal thickness possessed at each part of the bottom cover 12. When the thickness of the bottom cover 12 is not uniform, the minimum thickness of the bottom cover 12 is the thickness of the thinnest part of the bottom cover 12.

[0078] Specifically, examples of the minimum thickness h of the bottom cover 12 include 0.3 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 1.8 mm, 2 mm, 2.5 mm, 2.8 mm, 3 mm, 3.5 mm, 3.8 mm, 4 mm, 4.5 mm, 4.7 mm, 5 mm, 5.5 mm, 5.8 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm, 14 mm, 14.5 mm, 15 mm, 16 mm, 16.5 mm, 17 mm, 17.5 mm, 18 mm, 18.5 mm, 19 mm, 19.5 mm, etc. Preferably, 0.5 mm ≤ h ≤ 3 mm.

[0079] In this case, when the minimum thickness h of the bottom cover 12 satisfies 0.2 mm < h < 20 mm, it has been proven that the weight of the battery pack 100 can be effectively reduced and the structural strength is reasonable.

[0080] In the description of the present application, with the vertical direction as a reference, the "thickness" of a certain structure means the distance between two vertical side surfaces of the structure in the vertical cross-section. Although the "thickness" will not be described in detail in the following description, the content here can be referred to. Of course, for better understanding, the vertical direction is only for more easily explaining the technical solution of the present application and does not limit the usage mode of the battery pack 100.

[0081] In some embodiments, the weight m of the battery cell 20 and the minimum wall thickness h of the bottom cover 12 satisfy 0.03 mm / Kg ≤ h / m ≤ 100 mm / Kg.

[0082] The weight m of the battery cell 20 refers to the weight m of the battery cell 20 alone. When the battery pack 100 includes a plurality of battery cells 20, the weight of the battery cell 20 is the weight of each battery cell 20.

[0083] Specifically, the ratio of the minimum wall thickness h of the bottom cover 12 to the weight m of the battery cell 20 is as follows: 0.04mm / Kg, 0.05mm / Kg, 0.1mm / Kg, 0.4mm / Kg, 0.8mm / Kg, 1mm / Kg, 1.5mm / Kg, 2mm / Kg, 2.5mm / Kg, 3mm / Kg, 3.5mm / Kg, 4mm / Kg, 5mm / Kg, 6mm / Kg, 8mm / Kg, 10mm / Kg, 12mm / Kg Examples include 13mm / Kg, 15mm / Kg, 16mm / Kg, 18mm / Kg, 20mm / Kg, 30mm / Kg, 35mm / Kg, 40mm / Kg, 45mm / Kg, 50mm / Kg, 55mm / Kg, 60mm / Kg, 65mm / Kg, 68mm / Kg, 70mm / Kg, 75mm / Kg, 80mm / Kg, 85mm / Kg, 90mm / Kg, 95mm / Kg, and 98mm / Kg.

[0084] [Table 1]

[0085] Table 1 shows the test results regarding the impact on the safety of the battery pack 100 of the ratio between the minimum wall thickness h of the bottom cover 12 and the weight m of the battery cells 20, when tested according to the GB 38031-2020 standard, "Safety Requirements for Power Storage Batteries for Electric Vehicles". As can be seen from Table 1, when h / m is equal to 0.02 mm / Kg, the battery pack 100 is prone to ignition and explosion because the structural strength of the battery pack 100 does not meet the requirements. When h / m is greater than 0.02 mm / Kg, the structural strength of the bottom cover 12 is good and the battery pack 100 is less prone to ignition and explosion, but if h / m is too large, it is likely to result in wasted space and insufficient energy density, so preferably h / m is 100 mm / Kg or less.

[0086] In this case, if the minimum thickness h of the bottom cover 12 and the weight m of the battery cell 20 satisfy the condition 0.03 mm / Kg ≤ h / m ≤ 100 mm / Kg, the battery pack 100 is proven to not only have excellent structural strength but also high energy density and be less prone to ignition or explosion.

[0087] In some embodiments, referring together to Figures 5 to 7, the bottom cover 12 has a cover portion 12a and a mounting portion 12b, the mounting portion 12b is connected so as to surround the edge of the cover portion 12a, the cover portion 12a is used to define the housing cavity s, and the mounting portion 12b is connected to the main body 11.

[0088] The use of the lid portion 12a to define the housing cavity s means that the lid portion 12a, together with the body 11, surrounds the housing cavity s, and the mounting portion 12b is connected to the body 11 but does not participate in defining the housing cavity s. The lid portion 12a may be a plate-shaped, block-shaped member, or a flat plate-shaped, curved plate-shaped member, and is not particularly limited. As can be seen from Figure 6, the fact that the mounting portion 12b surrounds the edge of the lid portion 12a means that the mounting portion 12b is arranged along the edge of the lid portion 12a in a continuous structure that successfully closes and connects. As can be understood, in the vertical projection, the mounting portion 12b has a certain width, which allows it to have an appropriate contact area with the body 11, making it easy to position and attach the mounting portion 12b to the body 11, as well as easy to install the sealing member, and improving the sealing performance between the mounting portion 12b and the body 11.

[0089] The lid portion 12a and the mounting portion 12b may be integrally molded. If the bottom lid 12 is made of metal (e.g., aluminum, iron, stainless steel, etc.), the lid portion 12a and the mounting portion 12b may be integrally molded by means of die casting, forging, hot pressing, cold pressing, etc. If the bottom lid 12 is made of plastic (e.g., PP, PE, ABS, etc.), the lid portion 12a and the mounting portion 12b may be integrally molded by injection molding. The lid portion 12a and the mounting portion 12b may be molded separately and then joined. If the lid portion 12a and the mounting portion 12b are made of metal, the lid portion 12a and the mounting portion 12b may be welded or bonded. If the lid portion 12a and the mounting portion 12b are made of plastic, the lid portion 12a and the mounting portion 12b may be bonded. Of course, the lid portion 12a and the mounting portion 12b can also be fixedly connected by other means such as locking or riveting.

[0090] The lid portion 12a and the mounting portion 12b may be located on the same plane. Specifically, the two surfaces of the lid portion 12a and the mounting portion 12b facing the main body 11 may be located on the same plane, and / or the two surfaces of the lid portion 12a and the mounting portion 12b facing away from the main body 11 may be located on the same plane. When the two surfaces of the lid portion 12a and the mounting portion 12b facing the main body 11 and the two surfaces facing away from the main body 11 are located on the same plane, the lid portion 12a and the mounting portion 12b can form a flat bottom lid 12 (as shown in Figure 8).

[0091] The lid portion 12a and the mounting portion 12b do not have to be located on the same plane. Specifically, the lid portion 12a may be recessed into the main body 11 relative to the mounting portion 12b, or the lid portion 12a may protrude backward from the main body 11 relative to the mounting portion 12b, but is not limited to these. The thicknesses of the lid portion 12a and the mounting portion 12b may be the same or different, and are not particularly limited.

[0092] In this case, the bottom cover 12 defines the housing cavity s via the cover portion 12a and connects to the main body 11 via the mounting portion 12b, resulting in a clear structure and easy installation.

[0093] To make it clear, when the bottom cover 12 is sealed to the main body 11, the bottom cover 12 is sealed to the main body 11 via the mounting portion 12b, that is, the mounting portion 12b is sealed to the main body 11. Methods of sealing connection between the mounting portion 12b and the main body 11 include sealing connection by a sealing member and sealing connection by sealant, but details are not covered. The sealing member may be the sealing member described above, and the method of installing the sealing member may refer to the above description, the difference being that the sealing member is provided between the mounting portion 12b and the main body 11. When sealing connection by sealant is adopted between the mounting portion 12b and the main body 11, the sealant may be applied to the entire surface of the mounting portion 12b that is in contact with the main body 11.

[0094] To make it clear, when the bottom cover 12 is detachably connected to the main body 11, the bottom cover 12 is detachably connected to the main body 11 via the mounting portion 12b, that is, the mounting portion 12b is detachably connected to the main body 11. The method of detachably connecting the mounting portion 12b to the main body 11 can be described by referring to the method of detachably connecting the bottom cover 12 to the main body 11 described above, and since it is sufficient to provide the portion of the bottom cover 12 that is detachably connected to the main body 11 as the mounting portion 12b, the explanation of the method of detachably connecting the mounting portion 12b to the main body 11 will not be repeated.

[0095] In some embodiments, the mounting portion 12b is detachably connected to the main body 11.

[0096] Specifically, the bottom cover 12 further includes a fixing hole 12c provided in the mounting portion 12b, and the fastener 13 is fastened to the main body 11 after the fixing hole 12c in the mounting portion 12b is drilled. The fixing hole 12c is a through hole that penetrates the mounting portion 12b in the vertical direction, and specifically, the fixing hole 12c may be a smooth through hole (for example, if the fastener 13 is a rivet), a through hole with screw threads (for example, if the fastener 13 is a screw), or a through hole of other form (for example, a hexagonal hole, a square hole, a constricted hole, etc.). The specific form of the fixing hole 12c will vary depending on the specific form and setting method of the fastener 13, so it will not be described again here.

[0097] In some embodiments, the thickness of the lid portion 12a and the mounting portion 12b are equal.

[0098] When the lid portion 12a and the mounting portion 12b are integrally molded, they can be integrally molded by the methods described above, such as die-cast integral molding, cold press integral molding, hot press integral molding, and injection molding integral molding, which will not be described again here. Since the thickness of the lid portion 12a and the mounting portion 12b are the same, they can be quickly processed using the same metal plate as a base by pressing, cutting, etc., during molding.

[0099] In this case, the thickness of the lid portion 12a and the mounting portion 12b are equal, and the stress during molding is equal at each location, which improves the molding efficiency of the integral molding. Furthermore, since simple methods such as cutting sheet metal can be used to perform rapid processing, the structure of the bottom lid 12 becomes simpler, and processing becomes easier.

[0100] In some embodiments, referring to Figure 7, the lid portion 12a protrudes from the mounting portion 12b in a direction away from the housing cavity s.

[0101] As can be seen from the above, the fact that the lid portion 12a defines the housing cavity s and that the lid portion 12a protrudes away from the housing cavity s means that the lid portion 12a protrudes away from the main body 11. In other words, the lid portion 12a and the mounting portion 12b are offset vertically, and the lid portion 12a is located at the very bottom of the bottom lid 12.

[0102] When the lid portion 12a protrudes away from the housing cavity s relative to the mounting portion 12b, a certain redundant space can be formed between the lid portion 12a and the mounting portion 12b. This redundant space increases the distance between the lid portion 12a and the battery cell 20. Therefore, when an external force acts on the lid portion 12a, the redundant space can mitigate the external force, reducing or avoiding damage to the battery cell 20 caused by the external force. In particular, when the battery pack 100 is mounted on the bottom of the vehicle 1000 and the bottom lid 12 is located at the very bottom of the battery pack 100, there is a high possibility that stones from the ground will fly onto the bottom of the battery pack 100, i.e., the bottom lid 12, while the vehicle 1000 is in motion and collide with the bottom lid 12. In this case, the redundant space can reduce the impact of the external force on the battery cell 20. At the same time, because the lid portion 12a protrudes relative to the mounting portion 12b, the lid portion 12a of the bottom lid 12 can be used as a reinforcing structure for the bottom lid 12, improving the bending resistance of the bottom lid 12.

[0103] To make it clear, in this embodiment, the bottom cover 12 is located at the bottom of the housing 10 and is used to define the housing cavity s.

[0104] Figure 9 is a cross-sectional view of the battery pack 100 shown in Figure 4. In some embodiments, referring to Figure 9, the bottom cover 12 is provided at a distance from the battery cells 20.

[0105] The fact that the bottom cover 12 is provided at a distance from the battery cells 20 means that there is a predetermined distance r between the bottom cover 12 and the battery cells 20 in the vertical direction. Under the action of this predetermined distance r, a buffer space is formed between the bottom cover 12 and the battery cells 20, preventing external forces acting on the bottom cover 12 from being transmitted to the battery cells 20 and damaging them. In particular, when the battery pack 100 is attached to the bottom of the vehicle 1000 and the bottom cover 12 is located at the lowest part of the battery pack 100, stones and other objects from the ground are likely to fly to the bottom of the battery pack 100m and collide with the bottom cover 12 while the vehicle 1000 is in motion. In this case, the buffer space can block the effect of external forces transmitted to the battery cells 20 on the battery cells 20.

[0106] The arrangement of the gap between the bottom cover 12 and the battery cell 20 may consist of a redundant space formed between the protruding cover portion 12a and the mounting portion 12b in the above embodiment, or it may be configured such that a predetermined distance is maintained between one end of the battery cell 20 that is located inside the main body 11 and facing the bottom cover 12 and the other end of the main body 11 that faces the bottom cover 12. In other words, the battery cell 20 is located only within a portion of the housing cavity s defined by the main body 11, and not within the housing cavity s defined by the bottom cover 12, thereby maintaining a predetermined gap r between the battery cell 20 and the bottom cover 12 and ensuring the formation of a buffer space.

[0107] To make it clear, if the battery pack 100 contains multiple battery cells 20, all battery cells 20 are positioned with a gap between them and the bottom cover 12. Furthermore, to standardize the dimensions of the battery cells 20, the distance between each battery cell 20 and the bottom cover 12 is equal.

[0108] In some embodiments, referring to Figures 5 and 6, the bottom cover 12 has a feature surface d facing the housing cavity s, and the feature surface d is configured as a plane.

[0109] The fact that feature surface d faces the housing cavity s indicates that feature surface d is an inner surface of the bottom lid 12 that can define the housing cavity s. The fact that feature surface d is configured as a plane means that, in the direction of arrangement of the body 11 and bottom lid 12, feature surface d is a plane perpendicular to the direction of arrangement. In actual situations, if the body 11 and bottom lid 12 are arranged vertically, feature surface d of the bottom lid 12 is a plane parallel to the horizontal plane. If the body 11 and bottom lid 12 are arranged horizontally, feature surface d of the bottom lid 12 is a plane parallel to the vertical plane.

[0110] If the feature surface d is planar, the feature surface d can maintain a relatively uniform distance (this distance may be zero) from each battery cell 20 housed within the housing cavity s. Maintaining a relatively uniform distance between the feature surface d and the battery cells 20 allows more battery cells 20 to be housed in the housing cavity s, meaning that the space utilization rate of the housing cavity s is higher, the battery pack 100 can have a higher energy density, and the range of the battery pack 100 is increased.

[0111] To make it clear, if the bottom cover 12 has the cover portion 12a and the mounting portion 12b, the feature surface d may be formed by the inner structure of the cover portion 12a facing the housing cavity s. To make it clearer, if the bottom cover 12 is spaced apart from the battery cells 20, the feature surface d is spaced apart from the battery cells 20.

[0112] In some embodiments, the outer surface of the lid 12a away from the housing cavity s is parallel to the feature surface d.

[0113] The outer surface of the lid 12a, away from the housing cavity s, is positioned perpendicular to the feature surface d. The outer surface of the lid 12a is in contact with the atmospheric environment and is used to withstand the impact of external forces. When the outer surface of the lid 12a is a flat plane flush with the feature surface d, especially when the bottom lid 12 and the main body 11 are positioned perpendicularly at the bottom of the vehicle 1000, and the bottom lid 12 is located at the very bottom of the battery pack 100, having a flat outer surface of the lid 12a can significantly reduce the wind resistance generated by the battery pack 100, thereby reducing the running resistance of the vehicle 1000, reducing the energy consumption required for the vehicle 1000 to run, and contributing to improving the range of the battery pack 100.

[0114] Figure 10 is a schematic diagram of the orthographic projection of the bottom cover 12 in the vertical direction, as shown in Figure 6. Here, S1 represents the projected area of ​​the feature surface d, and S2 represents the projected area of ​​the bottom cover 12.

[0115] In some embodiments, in the vertical direction, the area S1 of the orthographic projection of feature surface d and the area S2 of the orthographic projection of bottom cover 12 satisfy S1 / S2 ≥ 0.2. Furthermore, S1 / S2 ≥ 0.5.

[0116] In the embodiment shown in Figure 10, in the vertical orthographic projection, the feature plane d is enclosed by the first feature edge d1, the second feature edge d2, the third feature edge d3, and the fourth feature edge d4, with their ends connected. The area S1 of the orthographic projection of the feature plane d is the area of ​​the region defined by the first feature edge d1, the second feature edge d2, the third feature edge d3, and the fourth feature edge d4. The area S2 of the orthographic projection of the bottom cover 12 is the area of ​​the region defined by the edge of the bottom cover 12.

[0117] Specifically, the ratio of the area S1 of the orthographic projection of feature surface d to the area S2 of the orthographic projection of the bottom cover 12 may be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.

[0118] [Table 2]

[0119] Table 2 shows the effect of the ratio of the orthographic area S1 of the feature surface d to the orthographic area S2 of the bottom cover 12 on the driving range of the battery pack 100 when tested according to the NEDC (New European Driving Cycle) standards. When S1 / S2 is less than 0.2, the driving range of the battery pack 100 is poor. This is because a small feature surface d results in a low space utilization rate of the housing cavity s, a small number of battery cells 20 housed in the battery pack 100, and a low energy density of the battery pack 100, leading to a short driving range and poor test results. When the S1 / S2 ratio reaches 0.2 or higher (especially when S1 / S2 reaches 0.5 or higher), the larger the ratio, the better the range of the battery pack 100. This is because the larger the characteristic surface d, the higher the space utilization rate of the housing cavity s, and the higher the energy density of the battery pack 100, resulting in a longer range for the battery pack 100 and increasingly better test results.

[0120] Since the feature surface d is flat, the larger the area of ​​the bottom cover 12 occupied by the feature surface d, the smaller the area of ​​the inner surface of the bottom cover 12 that is recessed or protruding relative to the feature surface d. The recessed inner surface relative to the feature surface d makes some of the space within the housing cavity s irregular, preventing the battery cells 20 from being installed and reducing the space utilization rate of the housing cavity s. The space within the housing cavity s formed by the inner surface protruding relative to the feature surface d is also irregular and prevents the battery cells 20 from being accommodated, further reducing the space utilization rate of the housing cavity s. When the space utilization rate of the housing cavity s is low, the volume occupied by the battery cells 20 per unit space within the battery pack 100 is small, and the energy density of the battery pack 100 becomes low. Therefore, the larger the area of ​​the bottom cover 12 occupied by the feature surface d, the greater the space utilization rate of the battery pack 100, the higher the energy density of the battery pack 100, and the longer the cruising range of the battery pack 100.

[0121] In some embodiments, as shown in Figure 10, the orthogonal projection of feature plane d in the vertical direction is rectangular.

[0122] As shown in Figure 10, the rectangular feature surface d is the region enclosed and defined by the first feature edge d1, the second feature edge d2, the third feature edge d3, and the fourth feature edge d4. In the battery pack 100, many of the battery cells 20 are assembled as a rectangular structure, and by making the structure of the feature surface d rectangular, it can be matched to the overall structure formed by the battery cells 20 within the battery pack 100, allowing more battery cells 20 to be placed in the housing cavity s, thereby contributing to improving the energy density of the battery pack 100.

[0123] Of course, in other embodiments, the orthographic projection of the feature surface d in the vertical direction may take on shapes such as circles, polygons, ellipses, or other irregular shapes.

[0124] In the embodiment of the present invention, the main body 11 includes a support member 11a.

[0125] The support member 11a may be a component that defines the housing cavity s in the main body 11 (for example, the support member 11a may be the top cover or frame described above), or it may be a component that is not used to define the housing cavity s but is located inside the housing cavity s (for example, the support member 11a may be the support plate described above), and is not particularly limited. If the support member 11a is used to define the housing cavity s, the support member 11a may be a component that is directly connected to the bottom cover 12 in the main body 11 (for example, the frame described above), or it may be a component that is not connected to the bottom cover 12 (for example, the top cover described above).

[0126] In some embodiments, the battery cell 20 is provided on the surface of the support member 11a.

[0127] In this case, the support member 11a is a component capable of carrying the weight of the battery cell 20, and it may be a carrier plate, a carrier bar, a carrier block, a carrier sheet, a carrier frame, a carrier rope, etc., and is not particularly limited. Specifically, when the battery cell 20 is supported by the support member 11a, the battery cell 20 may be provided above the support member 11a. Also specifically, when the battery cell 20 is suspended by the support member 11a, the battery cell 20 may be suspended on the wall surface of the support member 11a parallel to the gravitational direction of the battery cell 20.

[0128] The battery cell 20 may be provided above the support member 11a (for example, when the support member 11a is a support plate located within the accommodation cavity s), the battery cell 20 may be provided below the support member 11a (for example, when the support member 11a is an upper lid for defining the accommodation cavity s), and the battery cell 20 may be provided on the side of the support member 11a (for example, when the support member 11a is a frame for defining the accommodation cavity s).

[0129] In some embodiments, the battery cell 20 is adhered to the support member 11a.

[0130] Specifically, the battery cell 20 and the support member 11a may be adhered using an adhesive such as an epoxy resin-based adhesive, an acrylate-based adhesive, etc., but are not particularly limited. In this case, by adhering the battery cell 20 and the support member 11a, not only is the connection facilitated, but the structure of the battery pack 100 can be simplified.

[0131] In some embodiments, the battery cell 20 is provided on the surface of the support member 11a, and the minimum thickness H of the support member 11a and the weight M of the battery pack 100 satisfy 0.0002 mm / Kg < H / M ≤ 0.2 mm / Kg.

[0132] The thickness of the support member 11a refers to the distance between one side of the battery cell 20 and the opposite side of the support member 11a. When the battery cell 20 is provided on the vertical surface of the support member 11a, the minimum thickness H of the support member 11a refers to the point where the distance between the two vertical sides of the support member 11a is minimum. When the battery cell 20 is provided on the horizontal surface of the support member 11a, the thickness of the support member 11a refers to the point where the distance between the two horizontal sides of the support member 11a is minimum.

[0133] The weight of the battery pack 100 includes the weight of the main unit 11, the bottom cover 12, the battery cells 20, and other components (e.g., wire harness, thermal management system, power management system, etc.).

[0134] Specifically, the ratio of the minimum thickness H of the support member 11a to the weight M of the battery pack 100 may be designed to be 0.0003 mm / Kg, 0.0005 mm / Kg, 0.0008 mm / Kg, 0.001 mm / Kg, 0.003 mm / Kg, 0.005 mm / Kg, 0.008 mm / Kg, 0.01 mm / Kg, 0.03 mm / Kg, 0.05 mm / Kg, 0.06 mm / Kg, 0.08 mm / Kg, 0.1 mm / Kg, 0.12 mm / Kg, 0.15 mm / Kg, 0.16 mm / Kg, 0.19 mm / Kg, or 0.2 mm / Kg.

[0135] [Table 3]

[0136] Table 3 shows the results regarding the influence of the ratio of the minimum thickness H of several sets of support members 11a to the weight M of the battery pack 100 on the safety of the battery pack 100 when tested according to the standards of GB 38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles". As can be seen from Table 3, when the ratio of H / M is 0.0002 mm / Kg or less, the battery pack 100 catches fire or explodes. The reason is that the structural strength of the battery pack 100 does not meet the requirements. When the value of H / M exceeds 0.0002 mm / Kg, the battery pack 100 does not catch fire or explode. However, when H / M is too large (for example, when it exceeds 0.1), while the weight of the battery pack 100 is small, the thickness of the support plate is large, so the ratio of the battery cells 20 per unit volume of the battery pack 100 is low, the space utilization rate is low, the energy density of the battery pack 100 is too low, and the usage cost of the battery pack 100 becomes high. Furthermore, when 0.0005 mm / Kg ≤ H / M ≤ 0.1 mm / Kg, the structural strength of the battery pack 100 meets the requirements, and because the energy density of the battery pack 100 is high, the cruising ability of the battery pack 100 becomes stronger and does not cause safety accidents such as fire and explosion.

[0137] In some embodiments, the minimum thickness H of the support member 11a satisfies 0.2 mm < H < 20 mm.

[0138] Specifically, as the minimum thickness H of the support member 11a, it may be 0.3 mm, 0.5 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.2 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 9 mm, 10 mm, 12 mm, 15 mm, 16 mm, 18 mm, 19 mm. Furthermore, when 0.5 mm ≤ H ≤ 10 mm, the support member 11a has good structural strength, the overall strength of the battery pack 100 is good, and the battery pack 100 is less likely to catch fire or explode. At the same time, the ratio of the support member 11a to the overall volume of the battery pack 100 is small, the space utilization rate of the battery pack 100 is high, and the energy density of the battery pack 100 is high.

[0139] In some embodiments, referring to Figures 3 and 4, the battery cell 20 is suspended from the support member 11a.

[0140] The fact that the battery cell 20 is suspended from the support member 11a means that the battery cell 20 is located vertically below the support member 11a and that the support member 11a bears the weight of the battery cell 20. Methods for suspending the battery cell 20 from the support member 11a include directly bonding the battery cell 20 to the lower surface of the support member 11a, connecting the battery cell 2 to the support member 11a via a fastener 13 and positioning it below the support member 11a, and suspending the battery cell 20 from the support member 11a via a hook or the like and positioning it below the support member 11a.

[0141] In this case, since the battery cells 20 are suspended below the support member 11a and the bottom cover 12 is located at the bottom of the housing 10, when repairing the inside of the battery pack 100, if the bottom cover 12 can be removed without removing the support member 11a, the battery cells 20 can be exposed, making repair of the battery pack 100 easier. At the same time, when repairing the battery pack 100, the battery cells 20 can be attached to and detached from the support member 11a from below. In particular, if the support member 11a is subjected to force as at least part of the chassis of the vehicle 1000, the battery cells 20 can be attached to and detached from the support member 11a from below without removing the support member 11a, making repair of the battery pack 100 easier.

[0142] Figure 11 is a schematic diagram of the external appearance of a battery cell 20 according to a partial embodiment of the present invention. Figure 12 is a front view of the battery cell 20 shown in Figure 11.

[0143] In some embodiments, referring together to Figures 4 and 11, the outer surface of the battery cell 20 facing the support member 11a is the first outer surface m1, the battery cell 20 includes electrode terminals 21a, and the electrode terminals 21a are located on the outer surfaces of the battery cell 20 other than the first outer surface m1.

[0144] As described above, the electrode terminals 21a are components used for electrical connection with the electrode assembly 23 inside the battery cell 20 in order to output or input electrical energy from the battery cell 20. For electrical connection with the outside, at least a portion of the electrode terminals 21a extends outside the battery cell 20. Series and parallel connections between battery cells 20 are achieved by series and parallel connections between the respective electrode terminals 21a. The electrode terminals 21a are conductive in order to enable electrical transmission and may be aluminum electrodes, copper electrodes, etc.

[0145] The electrode terminals 21a are located on an outer surface of the battery cell 20 other than the first outer surface m1. The first outer surface m1 faces the support member 11a and is typically a smooth surface without protrusions or recesses of structures such as the electrode terminals 21a or fluid filling holes. When the battery cell 20 is suspended from the support member 11a, the first outer surface m1 is the upward-facing outer surface of the battery cell 20. Specifically, in one embodiment, the battery cell 20 comprises the case 22 and end cap 21 described above, and the case 22 and end cap 21 form the internal environment of the battery cell 20 that houses the electrode assembly 23. When the end cap 21 is located at one end of the case 22 and the electrode terminals 21a are located on the end cap 21, either outer surface of the case 22 may be used as the first outer surface m1 of the battery cell 20.

[0146] The electrode terminals 21a include a positive terminal and a negative terminal, the positive terminal being used for electrical connection with the positive electrode sheet in the electrode assembly 23, and the negative terminal being used for electrical connection with the negative electrode sheet in the electrode assembly 23. The positive and negative terminals may be located on the same outer surface of the battery cell 20 (e.g., a rectangular battery cell 20), or they may be located on two different outer surfaces of the battery cell 20 (e.g., a cylindrical battery cell 20). If the positive and negative terminals are located on two different outer surfaces of the battery cell 20, the first outer surface m1 is a surface different from the other two outer surfaces of the battery cell 20.

[0147] In addition to the battery cells 20, the battery pack 100 typically includes components such as a sampling wire harness, a high-voltage wire harness, and a shielding structure to protect the battery cells 20, which are electrically connected to each battery cell 20. In this case, if the electrode terminals 21a are placed on a surface other than the first outer surface m1 of the battery cell 20, and components such as the sampling wire harness and high-voltage wire harness are connected to the electrode terminals 21a, then the components can be positioned using the space between the battery cell 20 and other structures of the main body 11 other than the support member 11a (for example, the space between the battery cell and the bottom cover and / or the space between the battery cell and the inner surface of the main body), without being constrained by the support member 11a, making the installation of individual components easier. At the same time, because the first outer surface m1 is a smooth surface, the first outer surface m1 and the support member 11a can be bonded together, thereby enabling bonding between the battery cell 20 and the support member 11a, eliminating the need to retain space between the battery cell 20 and the support member 11a, and improving the space utilization rate of the battery pack 100.

[0148] In some embodiments, referring together to Figures 11 and 12, the battery cell 20 has a second outer surface m2 that is opposite to the first outer surface m1, and the electrode terminals 21a are located on the second outer surface m2.

[0149] The second outer surface m2 is an outer surface provided opposite the first outer surface m1 of the battery cell 20, and when the battery cell 20 is suspended from the support member 11a, the second outer surface m2 faces the bottom cover 12. As described above, the battery cell 20 and the bottom cover 12 may be spaced apart. In this case, there is a buffer space between the second outer surface m2 and the bottom cover 12, and the portion of the electrode terminal 21a extending from the battery cell 20 is located within this buffer space, so that wire harnesses and connecting sheets connected to the electrode terminal 21a can be placed within the buffer space. At the same time, as described above, the buffer space can block external forces hitting the bottom cover 12 from acting on the battery cell 20 and damaging the battery cell 20. Therefore, the buffer space not only blocks the effects of external forces but also allows for the routing of wire harnesses and the like, killing two birds with one stone. In addition, the space utilization rate of the buffer space and the battery pack 100 is also improved.

[0150] Of course, in other embodiments, referring to Figures 11 and 12, the electrode terminal 21a may be located on a third outer surface that intersects with the first outer surface m1 in the battery cell 20.

[0151] In some embodiments of the present invention, referring to Figures 4, 5, and 9, the support member 11a is located at the top of the housing 10 and is used to define the housing cavity s. Since the bottom cover 12 is located at the bottom of the housing 10, the support member 11a is positioned opposite the bottom cover 12. With the support member 11a as part of the top structure of the housing 10, the housing 10 can be mounted to a mounting body via the support member 11a. In this case, the battery cells 20 provided on the support member 11a can reinforce the strength of the support member 11a, further improving the rigidity of the top of the battery pack 100. This expands the application scenarios of the battery pack 100 to include cases where forces are applied to the top, such as when used as part of the chassis of a vehicle 1000.

[0152] Figure 13 is a schematic diagram of the structure of a support member 11a according to one embodiment of the present application. Figure 14 is a schematic diagram of the structure of a support member 11a according to another embodiment of the present application. Figure 15 is an orthographic projection of the support member 11a in the vertical direction shown in Figure 14.

[0153] In some embodiments, the support member 11a has a support surface f facing the housing cavity s, and the support surface f is configured as a flat plane.

[0154] The support surface f is the inner surface of the support member 11a facing the housing cavity s, and is used to define the housing cavity s. The fact that the support surface f is configured as a plane means that, in the arrangement direction of the main body 11 and the bottom cover 12, the support surface f is a plane perpendicular to the arrangement direction. In actual situations, when the main body 11 and the bottom cover 12 are arranged along the vertical direction, the support member 11a and the bottom cover 12 are arranged opposite each other along the vertical direction, and the support surface f of the support member 11a is a plane parallel to the horizontal plane. When the main body 11 and the bottom cover 12 are arranged along the horizontal direction, the support member 11a and the bottom cover 12 are arranged opposite each other along the horizontal direction, and the support surface f of the support member 11a is a plane parallel to the vertical plane.

[0155] As shown in Figure 13, the support member 11a may be the entire inner surface of the support member 11a facing the housing cavity s, in which case the support member 11a may be flat. As shown in Figures 14 and 15, the support member 11a may be a part of the inner surface of the support member 11a facing the housing cavity s, in which case the support surface f is merely the portion of the inner surface of the support member 11a that defines the housing cavity s.

[0156] If the support surface f is a plane, the support surface f can be maintained at a relatively uniform distance (this distance may be zero) from each battery cell 20 housed in the housing cavity s. When the distance between the support surface f and the battery cells 20 is maintained relatively uniformly, more battery cells 20 can be housed in the housing cavity s, meaning that the space utilization rate of the housing cavity s is higher, the battery pack 100 can have a higher energy density, and the range of the battery pack 100 is increased.

[0157] In some embodiments, the battery cell 20 is provided on the support surface f. The battery cell 20 is attached to the support member 11a via the support surface f. The battery cell 20 may be bonded to the support surface f, fixedly connected to the support surface f via fasteners 13 or the like, or welded or locked to the support surface f; there are no particular limitations.

[0158] Because the support surface f is flat, it can have a large contact area with the battery cells 20 installed thereon, making the mounting of the battery cells 20 more stable. At the same time, when the support surface f is flat, it can connect with more battery cells 20 compared to non-flat surfaces such as curved surfaces, increasing the number of battery cells 20 that can be installed in the battery pack 100, and further improving the space utilization rate and energy density of the battery pack 100.

[0159] To make it easier to understand, when the battery cell 20 is suspended from the support member 11a, the battery cell 20 is suspended from the support surface f.

[0160] In some embodiments, in the vertical direction, the area N1 of the orthographic projection of the support surface f and the area N2 of the orthographic projection of the support member 11a satisfy N1 / N2 ≥ 0.2. Furthermore, N1 / N2 ≥ 0.5.

[0161] In the embodiment shown in Figure 15, in the vertical orthographic projection, the support surface f is enclosed by the first support edge f1, the second support edge f2, the third support edge f3, and the fourth support edge f4, with their ends connected. The area N1 of the orthographic projection of the support surface f is the area of ​​the region defined by the first support edge f1, the second support edge f2, the third support edge f3, and the fourth support edge f4. The area N2 of the orthographic projection of the support member 11a is the area of ​​the region defined by the edge of the support member 11a.

[0162] Specifically, the ratio of the orthographic area N1 of the support surface f to the orthographic area N2 of the support member 11a may be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.

[0163] [Table 4]

[0164] Table 4 shows the effect of the ratio of the orthographic area N1 of the support surface f to the orthographic area N2 of the support member 11a on the driving range of the battery pack 100 when tested according to the NEDC (New European Driving Cycle) standards. When N1 / N2 is less than 0.2, the driving range of the battery pack 100 is poor. This is because a smaller support surface f results in fewer battery cells 20 supported by the support member 11a, a lower space utilization rate of the housing cavity s, and a lower energy density of the battery pack 100, leading to a shorter driving range and poor test results. When the ratio of N1 / N2 reaches 0.2 or higher (especially when N1 / N2 reaches 0.5 or higher), the larger the ratio, the longer the range of the battery pack 100. This is because a larger support surface f allows for a greater number of battery cells 20 to be supported by the support member 11a, increasing the space utilization rate of the housing cavity s and thus increasing the energy density of the battery pack 100. As a result, the range of the battery pack 100 increases, and the test structure improves. When the support member 11a is a flat plate structure as shown in Figure 13, the orthographic area N1 of the support surface f is equal to the orthographic area N2 of the support member 11a, resulting in the best range effect for the battery pack 100.

[0165] In some embodiments, the orthogonal projection of the support surface f in the vertical direction is rectangular.

[0166] As shown in Figure 15, the rectangular support surface f is the region enclosed and defined by the first support side f1, the second support side f2, the third support side f3, and the fourth support side f4. In the battery pack 100, many of the battery cells 20 are assembled as a rectangular structure, and by making the support surface f structure rectangular, it can be matched to the overall structure formed by the battery, allowing more battery cells 20 to be placed in the housing cavity s, which contributes to improving the energy density of the battery pack 100.

[0167] Of course, in other embodiments, the orthographic projection of the support surface f in the vertical direction may be, for example, circular, polygonal, elliptical, or other irregular shapes.

[0168] In some embodiments, referring to Figure 14, the support member 11a has a support portion 11a1 and a connecting portion 11a2, the connecting portion 11a2 being connected so as to surround the edge of the support portion 11a1, the support portion 11a1 being used to define the housing cavity s, and the connecting portion 11a2 being connected to the portion of the housing 10 other than the support member 11a.

[0169] The support portion 11a1 is used to define the housing cavity s, and the connecting portion 11a2 is used to connect to parts of the housing 10 other than the support member 11a, and does not participate in defining the housing cavity s. The support portion 11a1 may be plate-shaped, block-shaped, flat plate-shaped, curved plate-shaped, etc., and is not particularly limited. As can be seen from Figure 14, the fact that the connecting portion 11a2 surrounds the edge of the support portion 11a1 means that the connecting portion 11a2 presents a continuous structure that successfully closes and connects along the edge of the support portion 11a1. To understand this, in the vertical projection, the connecting portion 11a2 has a certain width, which allows it to have an appropriate contact area with other structures of the housing 10 other than the support member 11a, and makes it easier to attach and connect the connecting portion 11a2 to other structures of the housing 10 other than the support member 11a.

[0170] The support portion 11a1 and the connecting portion 11a2 may be integrally molded. If the support member 11a is made of metal (e.g., aluminum, iron, stainless steel, etc.), the support portion 11a1 and the connecting portion 11a2 may be integrally molded by means of die casting, forging, hot pressing, cold pressing, etc. If the support member 11a is made of plastic (e.g., PP, PE, ABS, etc.), the support portion 11a1 and the connecting portion 11a2 may be integrally molded by injection molding. Alternatively, the support portion 11a1 and the connecting portion 11a2 may be molded separately and then connected. If the support portion 11a1 and the connecting portion 11a2 are made of metal, the support portion 11a1 and the connecting portion 11a2 may be welded or bonded. If the support portion 11a1 and the connecting portion 11a2 are made of plastic, the support portion 11a1 and the connecting portion 11a2 may be bonded. Of course, the support portion 11a1 and the connecting portion 11a2 can also be fixedly connected by other means such as locking or riveting.

[0171] Specifically, the connecting portion 11a2 is connected to a part of the main body 11 other than the support member 11a, and the connection method may be either integral molding or fixed connection. If the connecting portion 11a2 is integrally molded with a part of the main body 11 other than the support member 11a, that is, if the main body 11 is a integrally formed part, it can be integrally molded by means such as die casting, forging, hot pressing, cold pressing, or injection molding. If the connecting portion 11a2 is fixedly connected to a part of the main body 11 other than the support member 11a, it is fixedly connected by means such as fastening via a fastener 13 or locking by an engagement structure, but is not particularly limited.

[0172] The support portion 11a1 and the connecting portion 11a2 can be located on the same plane. Specifically, the two surfaces of the support portion 11a1 and the connecting portion 11a2 facing the bottom cover 12 are located on the same plane, and / or the two surfaces of the support portion 11a1 and the connecting portion 11a2 facing away from the bottom cover 12 are located on the same plane. When the two surfaces of the support portion 11a1 and the connecting portion 11a2 facing the bottom cover 12 and the two surfaces facing away from the bottom cover 12 are located on the same plane, the support portion 11a1 and the connecting portion 11a2 can form a flat support member 11a (as shown in Figure 13).

[0173] The support portion 11a1 and the connecting portion 11a2 do not have to be located on the same plane. Specifically, the support portion 11a1 may protrude away from the housing cavity s relative to the connecting portion 11a2, or the support portion 11a1 may be recessed into the housing cavity s relative to the connecting portion 11a2, and this is not particularly limited. The support portion 11a1 and the connecting portion 11a2 may or may not have the same thickness, and this is not particularly limited.

[0174] In this case, the support member 11a defines the housing cavity s via the support portion 11a1, and the connecting portion 11a2 connects it to the structure of the main body 11 other than the support member 11a, making the structure clear.

[0175] To make it easier to understand, if the support member 11a includes the support portion 11a1 and the connecting portion 11a2, the battery cell 20 is provided on the support portion 11a1.

[0176] To make it clear, when the support member 11a includes the support portion 11a1 and the connecting portion 11a2, the inner structure of the support portion 11a1 facing the housing cavity s forms a support surface f.

[0177] In some embodiments, the support portion 11a1 protrudes from the connecting portion 11a2 in a direction away from the housing cavity s.

[0178] As can be seen from the above description, the fact that the support portion 11a1 defines the housing cavity s and the support portion 11a1 protrudes away from the housing cavity s means that the support portion 11a1 and the connecting portion 11a2 are positioned offset in the vertical direction. The support portion 11a1 is located at the top of the support member 11a. In this case, the space between the support portion 11a1 and the connecting portion 11a2 may form part of the housing cavity s, and this space can accommodate the battery cell 20.

[0179] When the support portion 11a1 protrudes away from the housing cavity s relative to the connecting portion 11a2, the support portion 11a1 acts as a reinforcing structure for the support member 11a, thereby improving the bending resistance of the support member 11a.

[0180] In some embodiments, the thickness of the support portion 11a1 and the connecting portion 11a2 are equal.

[0181] When the thickness of the support portion 11a1 and the connecting portion 11a2 are equal, the support portion 11a1 and the connecting portion 11a2 can be integrally molded from the same plate by die casting, cold pressing, or hot pressing, making the molding of the support member 11a easier. At the same time, because the thickness of the support portion 11a1 and the connecting portion 11a2 are equal, the stress at each point during molding becomes equal, improving the molding rate of the support member 11a.

[0182] In some embodiments, the outer surface of the support portion 11a1 away from the housing cavity s is parallel to the support surface f.

[0183] The outer surface of the support portion 11a1, away from the housing cavity s, is positioned opposite the support surface f in the vertical direction. The outer surface of the support portion 11a1 can come into contact with the atmospheric environment. When the battery pack 100 is mounted on the vehicle 1000, the support portion 11a1, with its flat outer surface, can reduce the driving resistance of the vehicle 1000, reduce the energy consumption required for the vehicle 1000 to run, and improve the driving range of the battery pack 100.

[0184] In some embodiments, referring to Figures 3, 4, and 9, the body 11 includes a frame 11b and a support member 11a, the frame 11 enclosing a cavity q that penetrates through both vertical ends, the bottom cover 12 and the support member 11a each cover the opposing vertical ends of the cavity q, and the bottom cover 12, frame 11b and support member 11a jointly enclose a housing cavity s.

[0185] The frame 11b itself encloses and forms a cavity q through which both ends in the vertical direction pass. The support member 11a covers the top of the cavity q, and the bottom cover 12 covers the bottom of the cavity q. In other words, the support member 11a is located at the top of the housing 10 and is used to define the housing cavity s, and the bottom cover 12 is located at the bottom of the housing 10 and is used to define the housing cavity s. The three components, frame 11b, support member 11a, and bottom cover 12, enclose the housing cavity s. The frame 11b, support member 11a, and bottom cover 12 may be made of the same material, such as aluminum alloy, copper alloy, steel, or plastic. Of course, the frame 11b, support member 11a, and bottom cover 12 may be made of different materials and are not particularly limited. As an orthographic projection in the vertical direction, the frame 11b may be rectangular, circular, polygonal, etc., and is not particularly limited.

[0186] If the support member 11a includes the support portion 11a1 and the connecting portion 11a2, the support member 11a is connected to the frame 11b via the connecting portion 11a2. If the bottom cover 12 includes the cover portion 12a and the mounting portion 12b, the bottom cover 12 is connected to the frame 11b via the mounting portion 12b.

[0187] In this case, by using frame 11b as the base and connecting the support member 11a and bottom cover 12 to both vertical ends of frame 11b, a housing cavity s for the battery pack 100 can be formed, and the structure of the housing 10 is simple.

[0188] In some embodiments, the support member 11a and the frame 11b are fixedly connected or integrally molded. The support member 11a and the frame 11b may be integrally molded by injection molding, die casting, forging, cold pressing, hot pressing, etc. The support member 11a and the frame 11b may be fastened via fasteners 13, locked via engagement structures, and fixedly connected by welding, bonding, heat welding, etc.

[0189] If the support member 11a and the frame 11b are integrally molded and the main body 11 is integrally molded, the housing 10 can be assembled by connecting the main body 11 to the bottom cover 12, making the assembly of the housing 10 easy. If the support member 11a and the frame 11b are fixedly connected, the molding process for the support member 11a and the frame 11b is relatively easy, and the processing cost of the housing 10 can be reduced.

[0190] To make it clear, if the support member 11a has a support portion 11a1 and a connecting portion 11a2, it is connected to the frame 11b by the connecting portion 11a2. If the bottom cover 12 has a cover portion 12a and a mounting portion 12b, it is connected to the frame 11b by the mounting portion 12b.

[0191] Figure 16 is a front view of the battery pack 100 shown in Figure 4. Referring to Figures 16 and 12, in some embodiments, in the vertical direction, the height Hc of the battery cell 20 and the height Hp of the battery pack 100 satisfy 0.02 ≤ Hc / Hp ≤ 0.98.

[0192] The height Hc of the battery cell 20 refers to the maximum vertical length of the battery cell 20 when the main body 11 and the bottom cover 12 are arranged vertically. Taking the battery cell 20 shown in Figure 12 as an example, when the first outer surface m1 of the battery cell 20 is positioned opposite the outer surface located at the electrode terminals 21a, the maximum length of the battery cell 20 refers to the distance between the electrode terminals 21a and the first outer surface m1. Of course, when the first outer surface m1 of the battery cell 20 is adjacent to the outer surface located at the electrode terminals 21a, the height Hc of the battery cell 20 refers to the distance from the first outer surface m1 of the battery cell 20 to the outer surface positioned opposite it.

[0193] The height Hp of the battery pack 100 refers to the maximum vertical length of the battery pack 100 when the main body 11 and the bottom cover 12 are arranged along the vertical direction.

[0194] Specifically, the ratio of the height Hc of the battery cell 20 to the height Hp of the battery pack 100 may be 0.02, 0.03, 0.05, 0.08, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, or 0.98.

[0195] [Table 5]

[0196] Table 5 shows the impact of the ratio of the height Hc of a set of battery cells 20 to the height Hp of the battery pack 100 on the safety of the battery pack 100, when tested according to the GB 38031-2020 standard, "Safety Requirements for Power Storage Batteries for Electric Vehicles". As can be seen from Table 5, when Hc / Hp exceeds 0.98, the height of the battery pack 100 occupied by the structure of the housing 10 is very small, the strength of the housing 10 does not meet the requirements, and it can cause safety accidents such as ignition and explosion. When Hc / Hp is 0.02 or less, the structural strength of the housing 10 can meet the requirements and does not cause situations of ignition and explosion. When Hc / Hp is less than 0.2, the structural strength of the housing 10 meets the requirements, but the space utilization rate of the battery pack 100 is low and the energy density is too low.

[0197] Furthermore, when 0.5 ≤ Hc / Hp < 0.94, the strength of the battery pack 100 meets the requirements, not only preventing safety accidents such as ignition and explosion, but also resulting in a high space utilization rate and high energy density for the battery pack 100.

[0198] According to some embodiments of the present invention, the battery pack 100 comprises a housing 10 and battery cells 20, the housing 10 encloses to form a housing cavity s and includes a bottom cover 12 located at its bottom to define the housing cavity s, the battery cells 20 housed within the housing cavity s, and the bottom cover 12 has a feature surface d facing the housing cavity s, the feature surface d being configured as a plane. When the feature surface d is a plane, the feature surface d can maintain a relatively uniform distance (this distance may be zero) from each battery cell 20 housed within the housing cavity s. When the distance between the feature surface d and the battery cells 20 is maintained relatively uniformly, more battery cells 20 can be housed in the housing cavity s, that is, the space utilization rate of the housing cavity s is higher, the battery pack 100 can have a higher energy density, and the range of the battery pack 100 is higher.

[0199] In other embodiments, the present invention further provides an electrical device comprising a battery pack 100 according to any one of the above embodiments, the battery pack 100 being used to supply electrical energy to the electrical device. For a description of the electrical device, please refer to the above description. It will not be repeated here.

[0200] Since the electrical device includes the battery pack 100, it has all the beneficial effects of the above embodiment. This will not be repeated here.

[0201] Figure 17 is a schematic diagram showing a battery pack 100 according to a partial embodiment of the present invention applied to a vehicle body 200. Figure 18 is a first exploded view of the structure shown in Figure 17. Figure 19 is a second exploded view of the structure shown in Figure 17.

[0202] In some embodiments, referring to Figures 17 to 19, the electrical equipment includes a vehicle 1000, and the battery pack 100 is located at the bottom of the vehicle body 200 of the vehicle 1000. For a description of the vehicle 1000, please refer to the above description; it will not be repeated here.

[0203] The vehicle body 200 of the vehicle 1000 refers to the part of the vehicle 1000 that carries people and luggage, and includes the driver's seat, passenger compartment, engine room, trunk room, etc. The vehicle body 200 generally includes the case 22 of the vehicle body 200, doors, windows, trim, seats, air conditioning equipment, etc., located in the case 22 of the vehicle body 200. The case 22 of the vehicle body 200 usually refers to a structure composed of major load-bearing elements of the vehicle 1000 such as longitudinal beams, cross members, chassis, struts, etc., and sheet metal parts connected thereto. In the embodiment of the present application, the provision of the battery pack 100 at the bottom of the vehicle body 200 mainly refers to the provision of the battery pack 100 at the bottom of the case 22 of the vehicle body 200.

[0204] In this case, placing the battery pack 100 at the bottom of the vehicle body 200 does not occupy space inside the vehicle body 200, thus contributing to a reduction in the volume and weight of the vehicle body 200.

[0205] Figure 20 is a schematic diagram of the mounting relationship between a battery pack 100 and a vehicle body 200 according to some embodiments of the present application. In some embodiments, referring to Figure 20, the main body 11 includes a support member 11a located at the top of the housing 10, the support member 11a is used to define a housing cavity s, and in the vertical direction, the distance L between the support member 11a and the vehicle body 200 satisfies L≧0.

[0206] Since the battery pack 100 is located at the bottom of the vehicle body 200 and the support member 11a is located at the top of the housing 10, the support member 11a is closest to the vehicle body 200 in the battery pack 100. The distance L between the support member 11a and the vehicle body 200 refers to the distance in the vertical direction between the uppermost part of the support member 11a and the vehicle body 200 located above it. If the support member 11a includes the support portion 11a1 and the connecting portion 11a2, the distance L between the support member 11a and the vehicle body 200 is the distance between the outer surface of the support portion 11a1 away from the housing cavity s and the vehicle body 200 located above it.

[0207] When the distance L between the support member 11a and the vehicle body 200 is 0, the support member 11a and the vehicle body 200 are bonded together. When the distance L between the support member 11a and the vehicle body 200 is greater than 0, the support member 11a is separated from the vehicle body 200 and is not bonded to it. To make this clear, in this case, the bottom cover 12 is located at the bottom of the support member 11a, and the distance g between the bottom cover 12 and the vehicle body 200 is greater than 0.

[0208] When the battery pack 100 is installed below the vehicle body 200, the area within the distance from the bottom of the battery pack 100 to the vehicle body 200 becomes the installation space occupied by the battery pack 100. When the support member 11a and the vehicle body 200 are separated, a certain amount of wasted space exists between the battery pack 100 and the vehicle body 200. By bonding the support member 11a and the vehicle body 200 together, the wasted space between the battery pack 100 and the vehicle body 200 can be contained within the spatial range of the battery pack 100. In this way, when occupying the same space below the vehicle body 200, bonding the battery pack 100 and the vehicle body 200 together increases the volume of the battery pack 100, and further improves the power and energy density of the battery pack 100.

[0209] In this case, when the distance L between the support member 11a and the vehicle body 200 is 0, the battery pack 100 has high power and high energy density, and the vehicle 1000 has a strong driving range. When the distance L between the support member 11a and the vehicle body 200 is greater than 0, the mounting of the support member 11a is flexible.

[0210] In some embodiments, referring to Figures 17 to 19, the main body 11 includes a support member 11a located at the top of the housing 10, the support member 11a is used to define the housing cavity s, and the battery pack 100 is attached to the vehicle body 200 via the support member 11a.

[0211] Since the battery pack 100 is located at the bottom of the vehicle body 200 and the support member 11a is located at the top of the housing 10, in the battery pack 100, the support member 11a is closest to the vehicle body 200, and the battery pack 100 is attached to the vehicle body 200 via the support member 11a. Specifically, the support member 11a may be fixed to the vehicle body 200 by means of fasteners 13 (e.g., screws, bolts, rivets, etc.), welding, etc.

[0212] When the battery cell 20 is mounted on the support member 11a, the structure formed by the battery cell 20 and the support member 11a is connected to the vehicle body 200, improving the top strength of the battery pack 100 and further improving the mounting strength of the battery pack 100.

[0213] In some embodiments, the support member 11a is configured to form at least a portion of the chassis of the vehicle body 200.

[0214] The chassis, as part of the vehicle body 200, is composed of a combination of four parts: the transmission system, the running system, the steering system, and the braking system. It supports and mounts the engine and its various components and components of the vehicle 1000, forms the overall shape of the vehicle 1000, withstands engine power, and ensures normal operation.

[0215] The chassis is located at the bottom of the vehicle body 200, and the support member 11a functions directly as at least part of the chassis. In other words, the support member 11a is used to form at least part of the chassis of the vehicle body 200. By integrating the support member 11a with the chassis of the vehicle body 200 in this way, the space occupied by the gap between the conventional chassis and the battery pack 100 can be contained within the battery pack 100, increasing the space of the battery pack 100, thereby increasing the energy of the battery pack 100 and contributing to improving the driving range of the vehicle 1000.

[0216] According to some embodiments of the present application, referring to Figures 17 to 19, the electrical device includes a vehicle 1000, and a battery pack 100 is provided at the bottom of the vehicle body 200 of the vehicle 1000. The battery pack 100 includes a housing 10 and battery cells 20, the housing 10 includes a support member 11a located at its top, the battery cells 20 are located inside the housing 10 and suspended from the support member 11a, and the electrode terminals 21a of the battery cells 20 are located on the outer surface of the battery cells 20 away from the support member 11a, and the support member 11a forms at least a part of the vehicle chassis 1000.

[0217] In this case, the battery cell 20 is suspended from the support member 11a, which improves the strength of the support member 11a and further improves the top strength of the battery cell 20, so that a certain stress requirement can be achieved when the support member 11a is used as a chassis. At the same time, since the electrode terminals 21a of the battery cell 20 are separated from the support member 11a, the battery cell 20 can be directly attached to the support member 11a, eliminating the gap between the battery cell 20 and the support member 11a. The saved gap can be used to increase the mounting space for the battery cell 20, thereby increasing the energy of the battery pack 100 and further improving the driving range of the vehicle 1000.

[0218] The technical features of the embodiments described above can be combined in any way, and for the sake of brevity, not all possible combinations of the technical features of the embodiments described above are listed. However, any combination of these technical features should be considered within the scope of this specification as long as it is inconsistent.

[0219] The embodiments described above are merely examples of some embodiments of the present application, and although their descriptions are specific and detailed, they should not be understood as limiting the scope of the present application. Furthermore, those skilled in the art can make some modifications and improvements without departing from the concept of the present application, and all of these will fall within the scope of protection. Therefore, the scope of protection of the present application should be defined by the attached claims.

Claims

1. A housing that encloses to form a housing cavity and has a bottom cover located at its own bottom to partition the housing cavity, A battery pack comprising a battery cell housed in the aforementioned housing cavity, The bottom cover has a characteristic surface facing the housing cavity, and the characteristic surface is configured as a flat surface. The battery pack further comprises a support member and a frame, the frame enclosing a cavity that penetrates through both ends in the vertical direction, the bottom cover and the support member respectively cover the opposing ends of the cavity in the vertical direction, and the bottom cover, the frame and the support member jointly enclose the housing cavity.

2. The battery pack according to claim 1, wherein in the vertical direction, the area S1 of the orthographic projection of the feature surface and the area S2 of the orthographic projection of the bottom cover satisfy S1 / S2 ≥ 0.

2.

3. The battery pack according to claim 1, wherein the orthographic projection of the characteristic surface in the vertical direction is rectangular.

4. The bottom cover is a battery pack having a lid portion for defining the housing cavity and a mounting portion connected so as to surround the edge of the lid portion and attached to a part of the housing other than the bottom cover, The battery pack according to claim 1, wherein the inner surface structure of the lid facing the housing cavity forms the characteristic surface.

5. The battery pack according to claim 4, wherein the outer surface of the lid that is away from the housing cavity is parallel to the characteristic surface.

6. The battery pack according to claim 4, wherein the lid portion is provided to protrude away from the housing cavity relative to the mounting portion.

7. The battery pack according to claim 4, wherein the lid portion is equal in thickness to the mounting portion.

8. The battery pack according to claim 1, wherein the bottom cover is provided at a distance from the battery cells.

9. The battery pack according to claim 1, wherein the support member is located at the top of the housing and defines a housing cavity, and the battery cells are suspended from the support member.

10. The battery pack according to claim 9, wherein the outer surface of the battery cell facing the support member is a first outer surface, and the battery cell includes electrode terminals arranged on an outer surface other than the first outer surface of the battery cell.

11. The battery pack according to claim 10, wherein the battery cell has a second outer surface arranged opposite to the first outer surface, and the electrode terminals are arranged on the second outer surface.

12. The battery pack according to claim 9, wherein the battery cell is bonded to the support member.

13. The battery pack according to claim 1, wherein the support member is fixedly connected to or integrally molded with the frame.

14. An electrical device comprising a battery pack according to any one of claims 1 to 13 for supplying electrical energy to the electrical device.

15. The electrical device according to claim 14, wherein the electrical device includes a vehicle, and the battery pack is provided at the bottom of the vehicle body.

16. The electrical device according to claim 15, wherein the battery pack is attached to the vehicle body via the support member.

17. The electrical device according to claim 16, wherein the support member is configured to form at least a part of the chassis of the vehicle body.

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