Battery pack housing, battery pack, and electrical device

Abstract

The electric device includes a battery pack. The battery pack includes a battery pack housing. The battery pack housing includes a tray and n layers of cooling plates. The tray includes first and second side beams facing each other, and m stages are separately arranged on opposite sides of the first and second side beams, where m≧3, two opposite ends of the n layers of cooling plates are arranged on corresponding stages of the first and second side beams, each layer of cooling plate corresponds to one stage, and each layer of cooling plate is used to arrange layers of battery cells, where 2≦n≦m, the m stages and the n layers of cooling plate are numbered in ascending order from the bottom to the top of the first side beam, and the size of the (n−1)th layer of cooling plate in the direction from the first side beam to the second side beam is smaller than the size of the nth layer of cooling plate.

Description

[Technical Field]

[0001] This application claims priority to Chinese Patent Application No. 202310306608.6, entitled "BATTERY PACK HOUSING, BATTERY PACK AND ELECTRICAL DEVICE," filed with the State Intellectual Property Office of the People's Republic of China on March 21, 2023, which is incorporated herein by reference in its entirety.

[0002] This application relates to the field of battery technology, and in particular to battery pack housings, battery packs, and electrical devices. [Background technology]

[0003] As the core of an electric vehicle, a battery pack provides energy for starting and running the electric vehicle, thereby providing an environmentally friendly means of transportation for people to move. The battery pack can be further applied in the fields of outdoor energy storage and home energy storage to improve energy utilization efficiency and reliability.

[0004] Current battery packs mainly use a single-layer battery cell arrangement to meet the requirements of the overall vehicle and structural reliability. With the continuous and iterative technology upgrades, especially with the increasing demand for long-distance driving, in order to increase the driving range of electric vehicles, the battery cell capacity needs to be increased or the number and integration of battery cells needs to be improved. However, it is currently difficult to significantly improve the battery cell capacity and integration. Therefore, how to increase the number of battery cells in a battery pack has become a major research direction.

[0005] Considering the limited installation space of electric vehicles, it is difficult to efficiently increase the number of battery cells in current battery packs using a single-layer battery cell arrangement. Currently, there is research into stacking multiple battery packs to form an entire battery pack. However, such a method results in a battery pack with a large overall volume, making it difficult to use in practice. Summary of the Invention

[0006] The purpose of this application is to provide a battery pack housing, a battery pack, and an electrical device to solve the problem that stacked battery packs are huge in volume and difficult to use in practice.

[0007] In order to achieve the objectives of this application, this application provides the following technical solutions:

[0008] According to a first aspect, the present application provides: a tray including first and second side beams opposed to each other, wherein m tiers are separately disposed on each of the opposing sides of the first and second side beams, m≧3, and the m tiers are numbered in ascending order from the bottom to the top of the first side beam; n layers of cooling plates, each of whose two opposing ends is disposed on a corresponding step of the first side beam and the second side beam, each layer of the cooling plates corresponding to one step, each layer of the cooling plates being used for arranging a layer of battery cells, 2≦n≦m, and the n layers of the cooling plates being numbered in ascending order from the bottom to the top of the first side beam; The present invention provides a battery pack housing, including a

[0009] In the direction from the first side beam to the second side beam, the size of the (n-1)th layer of the cooling plate is smaller than the size of the nth layer of the cooling plate.

[0010] In one embodiment, the cooling plate is secured to the first and second side beam stages by welding with a welding rod, or the cooling plate is secured to the first and second side beam stages by bonding with an adhesive tape.

[0011] In one embodiment, adhesive slots are formed in the tops of the first and second side beams, respectively, and the adhesive slots are configured to be filled with adhesive. The battery pack housing further includes a cover plate that covers the tops of the first and second side beams and is bonded to the adhesive in the adhesive slots.

[0012] In one embodiment, raised snap walls are further disposed on the top edges of the first and second side beams, and the periphery of the cover plate snaps into the snap walls.

[0013] In one embodiment, the ends of the first and second side beams in the length direction are further connected to a connecting beam, and at least one of the first side beam, the second side beam, and the connecting beam is provided with an explosion-proof valve.

[0014] In one embodiment, the other longitudinal ends of the first and second lateral beams are further connected to an attachment beam, and the connection beam and attachment beam are configured to attach and secure the first lateral beam to the second lateral beam.

[0015] In one embodiment, a battery cell control member is disposed on the mounting beam, the battery cell control member configured to electrically connect to the battery cell.

[0016] In one embodiment, the battery pack housing further includes an insulating layer and a bottom plate, the insulating layer being disposed on a side of the first layer of cooling plates facing away from the second layer of cooling plates, the bottom plate being disposed on a side of the insulating layer facing away from the first layer of cooling plates, and the bottom plate being secured to the first side beam and the second side beam.

[0017] In one embodiment, the height of the (m-1)th step relative to the (m-2)th step is equal to or greater than the total height of the (n-2)th layer of cooling plates and the (n-2)th layer of battery cells.

[0018] In one embodiment, the cold plate is any one of an air cold plate, a liquid cold plate, or a direct cold plate.

[0019] In one embodiment, the battery pack housing further includes a thermal protection member configured to be disposed between two battery cells of at least one layer of battery cells.

[0020] In one embodiment, the thermal protection member includes at least one of a thermally conductive layer, a heat absorbing layer, and a thermally insulating layer that are stacked together.

[0021] In one embodiment, the heat absorbing layer is made of a phase change heat absorbing material.

[0022] According to a second aspect, the present application further provides a battery pack including a battery cell and a battery pack housing according to any one of the various embodiments in the first aspect, wherein the battery cell is disposed on a cooling plate of the battery pack housing.

[0023] In one embodiment, a plurality of battery cells are provided and divided into n layers, with a layer of battery cells disposed on each layer of the cooling plate.

[0024] In one embodiment, in the direction from the first side beam to the second side beam, the size of the (n-1)th layer of battery cells is smaller than the size of the nth layer of battery cells.

[0025] In one embodiment, the direction from the first side beam to the second side beam is the length direction of the battery cells, and the length of the (n-1)th layer of the battery cells is less than the length of the nth layer of the battery cells.

[0026] In one embodiment, at least two of the n layers of battery cells are of different types.

[0027] According to a third aspect, the present application further provides an electric device including a battery pack according to any one of the various embodiments in the second aspect.

[0028] The tray includes a first side beam and a second side beam, m stages are separately arranged on opposite sides of the first side beam and the second side beam, n layers of cooling plates are arranged on the corresponding stages, each layer of the cooling plates is used for arranging a layer of battery cells, and the n layers of cooling plates perform thermal management to ensure reliable and stable operation of the battery pack. Compared with existing solutions in which multiple battery packs are stacked to form a whole, the battery pack in the embodiment of the present application has a compact structure, a small volume, and is easy to actually use.

[0029] In order to more clearly describe the embodiments of the present application or the technical solutions in the prior art, the following will briefly describe the accompanying drawings needed to describe the embodiments or the prior art. It is obvious that the accompanying drawings in the following description only show some embodiments of the present application, and those skilled in the art can still derive other drawings from the accompanying drawings without creative efforts. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 2 is an exploded view of the structure of a battery pack according to one embodiment. [Figure 2] 2 is an exploded view of the battery pack structure of FIG. 1 from another perspective. [Figure 3]FIG. 2 is a top view of the battery pack of FIG. [Figure 4] FIG. 4 is an exploded cross-sectional view of the structure taken along the direction AA in FIG. 3. [Figure 5] 1 is a diagram of a structure of an electrical device according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0031] The technical solutions in the embodiments of the present application are clearly and completely described below in combination with the accompanying drawings in the embodiments of the present application. Of course, the described embodiments are not all of the embodiments, but only some of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative work shall fall within the protection scope of the present application.

[0032] It should be noted that when a component is considered to be "fixed" to another component, the component may be directly disposed on the other component, or intermediate components may also be present. When a component is considered to be "connected" to another component, the component may be directly connected to the other component, or intermediate components may also be present.

[0033] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the art of this application. The terms used in the specification of this application are merely for the purpose of describing particular embodiments and are not intended to limit this application. The term "and / or" used in this application includes any combination of one or more of the associated listed items.

[0034] Some embodiments of the present application are described in detail below in combination with the accompanying drawings. Where there is no contradiction, the following embodiments and features in the embodiments can be combined with each other.

[0035] 1 to 4, one embodiment of the present application provides a battery pack including a battery pack housing and battery cells, the battery pack housing including a tray 10 and n layers of cooling plates. A plurality of battery cells are provided and divided into n layers, and the layers of battery cells are separately disposed on each layer of the cooling plates.

[0036] 1, 2 and 4 show that the cold plate includes a first cold plate 21 and a second cold plate 22, and the battery cells include a first layer of battery cells and a second layer of battery cells.

[0037] The tray 10 includes a first side beam 11 and a second side beam 12 facing each other, and m stages are separately arranged on each of the opposing sides of the first side beam 11 and the second side beam 12, where m≧3.

[0038] Two opposite ends of n layers of cooling plates are arranged on corresponding stages of the first lateral beam 11 and the second lateral beam 12, each layer of the cooling plates corresponds to one stage, and each layer of the cooling plates is used for arranging a layer of battery cells, where 2≦n≦m.

[0039] From the bottom to the top of the first side beam 11, the m stages and n layers of cooling plates are numbered in ascending order. Figure 4 shows the first stage 121, the second stage 123, the third stage 125, the first layer of cooling plates (first cooling plate 21), and the second layer of cooling plates (second cooling plate 22), where m = 3 and n = 2. It should be understood that in this application, as the main embodiment for discussion, the values ​​of m and n may be other values, and this is not limited.

[0040] The first lateral beam 11 and the second lateral beam 12 may be made from a solid bar by a machining process such as cutting, or may be made from a solid bar by a process such as die casting and forging, or may be a hollow structure obtained by assembling multiple sheet structures by a process such as welding, but this is not limited to this.

[0041] The first and second side beams 11, 12 are parallel to each other, and steps are formed on opposite sides of the first and second side beams 11, 12. The shapes of the first and second side beams 11, 12 may be mirror symmetric.

[0042] 4 and taking the second side beam 12 as an example, the second side beam 12 is provided with three steps, namely a first step 121, a second step 123, and a third step 125. The first step 121 serves as the bottom of the second side beam 12 and protrudes from the second step 123 towards the first side beam 11. The second step 123 serves as the central part of the second side beam 12 and protrudes from the third step 125 towards the first side beam 11. The first step 121 is provided with a first step surface 122, the second step 123 is provided with a second step surface 124, and the third step 125 is provided with a third step surface 126. The first step surface 122 may be parallel to the second step surface 124, and the third step surface 126 may be parallel or not parallel to the second step surface 124, but this is not limited thereto. The first step surface 122, the second step surface 124, and the third step surface 126 may all be flat, or may, of course, be curved. The embodiments of the present application are mainly illustrated by taking flat surfaces as examples. The surface of the third step 125 serves as the top surface of the second side beam 12. Optionally, the number of steps of the second side beam 12 is not limited to three, but may be four, five, six, etc., i.e., m is not limited to 3, but may be 4, 5, 6, etc., which is not limited.

[0043] The shape of the first side beam 11 should be referenced to the shape of the second side beam 12. For example, referring to Figure 4, if the second side beam 12 has three steps, the first side beam 11 also has three steps, and the step surfaces of the corresponding steps at each level are arranged in the same plane. That is, the step surface of the first step 121 of the first side beam 11 and the first step surface 122 of the second side beam 12 are arranged in the same plane to form a first support surface, the step surfaces of the second step 123 of the first side beam 11 and the second step surface 124 of the second side beam 12 are arranged in the same plane to form a second support surface, and the step surfaces of the third step 125 of the first side beam 11 and the third step surface 126 of the second side beam 12 are arranged in the same plane to form a third support surface.

[0044] A gap exists between the first side beam 11 and the second side beam 12, i.e., a gap exists between the first step 121 of the first side beam 11 and the first step 121 of the second side beam 12, so that a cavity hole 15 is formed. Optionally, the extension direction of the first side beam 11 and the second side beam 12 is the length direction of the tray 10, the direction from the first side beam 11 to the second side beam 12 is the width direction of the tray 10, and the length direction and width direction of the cavity hole 15 correspond to the length direction and width direction of the tray 10, respectively.

[0045] The tray 10 further includes a connecting beam 13 and a mounting beam 14, with the connecting beam 13 connected to one end of the first and second side beams 11, 12 in the length direction (i.e., the direction of extension of the first and second side beams 11, 12, also referred to as the length direction of the tray 10), and the mounting beam 14 connected to the other opposite end of the first and second side beams 11, 12 in the length direction. In that way, the tray 10 forms a ring-shaped structure, with the first side beam 11 attached and fixed to the second side beam 12 by using the connecting beam 13 and the mounting beam 14, so that the tray 10 forms a whole.

[0046] The connecting beam 13 and the mounting beam 14 may be of a flat plate shape, a rod shape, or other structures, but are not limited thereto. Optionally, referring to Figures 1 and 2, the connecting beam 13 is of a flat plate structure, and the mounting beam 14 is of a "[" shaped plate structure, and the two ends of the "[" shaped structure are respectively connected to the ends of the first lateral beam 11 and the second lateral beam 12 in the length direction.

[0047] Considering m=3 and n=2 as an example, the arrangement relationship between the cooling plate and the stage is shown as follows:

[0048] Two opposing ends of the first cooling plate 21 are disposed on the first steps 121 of the first side beam 11 and the second side beam 12. Specifically, one end of the first cooling plate 21 is attached to the step surface of the first step 121 of the first side beam 11, and the other end of the first cooling plate 21 is attached to the first step surface 122 of the first step 121 of the second side beam 12. The shape of the first cooling plate 21 matches the shape of the tray 10. For example, the length direction of the first cooling plate 21 is the length direction of the tray 10, i.e., the length direction of the first side beam 11 or the second side beam 12, and the width direction of the first cooling plate 21 is the width direction of the tray 10, i.e., the direction from the first side beam 11 to the second side beam 12. The first cooling plate 21 is attached and fixed to the first stage 121 of the first side beam 11 and the second side beam 12, and the method of attachment and fixing is not limited.

[0049] The first layer of battery cells is disposed on the first cooling plate 21. The first layer of battery cells is attached and fixed to the first cooling plate 21, and the attachment and fixing method may be bonding. For example, a structural adhesive or a thermally conductive adhesive may be used to fix the first layer of battery cells to the first cooling plate 21. The first cooling plate 21 can control the temperature of the first layer of battery cells. Temperature control may mean dissipating heat from the first layer of battery cells or heating the first layer of battery cells. The specific structure of the first layer of battery cells is not limited.

[0050] Two opposing ends of the second cooling plate 22 are disposed on the second steps 123 of the first side beam 11 and the second side beam 12. Specifically, one end of the second cooling plate 22 is attached to the step surface of the second step 123 of the first side beam 11, and the other end of the second cooling plate 22 is attached to the second step surface 124 of the second step 123 of the second side beam 12. The shape of the second cooling plate 22 matches the shape of the tray 10. For example, the length direction of the second cooling plate 22 is the length direction of the tray 10, i.e., the length direction of the first side beam 11 or the second side beam 12, and the width direction of the second cooling plate 22 is the width direction of the tray 10, i.e., the direction from the second side beam 12 to the second side beam 12. The second cooling plate 22 is attached and fixed to the second stage 123 of the first side beam 11 and the second side beam 12, and the attaching and fixing method is not limited.

[0051] The second layer of battery cells is disposed on the second cooling plate 22. The second layer of battery cells is attached and fixed to the second cooling plate 22, and the attachment and fixing method may be bonding. For example, a structural adhesive or a thermally conductive adhesive may be used to fix the second layer of battery cells to the second cooling plate 22. The second cooling plate 22 can control the temperature of the second layer of battery cells. Specifically, temperature control may mean dissipating heat in the second layer of battery cells or heating the second layer of battery cells. The specific structure of the second layer of battery cells is not limited. The first layer of battery cells and the second layer of battery cells may be the same or different types of battery cells, such as, but not limited to, a lithium iron phosphate battery, a ternary system battery, or a cylindrical battery, a rectangular housing battery, or a soft pack battery.

[0052] Referring to FIG. 4, the height of the (m-1)th step relative to the (m-2)th step is equal to or greater than the total height of the (n-2)th layer of cooling plates and the (n-2)th layer of battery cells.

[0053] Specifically, the height of the second tier 123 relative to the first tier 121 must not be less than the total height of the first cooling plate 21 and the first layer of battery cells relative to the first tier 121, i.e., the distance between the second tier surface 124 and the first tier surface 122 must not be less than the total height of the first cooling plate 21 and the first layer of battery cells, so as to prevent the first layer of battery cells from interfering with the second cooling plate 22 to avoid failure of the attachment and fixation of the second cooling plate 22 to the second tier 123.

[0054] Similarly, the height of the third tier 125 relative to the second tier 123 must not be less than the total height of the second cooling plate 22 and the second layer of battery cells relative to the second tier 123, i.e., the distance between the third tier surface 126 and the second tier surface 124 must not be less than the total height of the second cooling plate 22 and the second layer of battery cells so as to prevent the second layer of battery cells from interfering with the cover plate 60 to avoid failure of the attachment and fixation of the cover plate 60 to the third tier 125.

[0055] The side surface of the first step 121 may be a plane perpendicular to the step surface of the first step 121, and the side surface of the second step 123 may be a plane perpendicular to the step surface of the second step 123. Taking the second side beam 12 as an example, the side surface of the first step 121 (the surface facing the first side beam 11; the same applies hereinafter) is perpendicular to the first step surface 122, and the side surface of the second step 123 is perpendicular to the second step surface 124. The first step surface 122 is parallel to the bottom surface of the first side beam 11, and the bottom and top surfaces of the second side beam 12 (i.e., the third step surface 126) are parallel. Therefore, the tray 10 has a simple structure and is convenient for attachment to other structures.

[0056] The side surface of the first step 121 is connected to the first step surface 122 and the bottom surface of the second side beam 12, the side surface of the second step 123 is connected to the second step surface 124 and the first step surface 122, and the side surface of the third step 125 is connected to the third step surface 126 and the second step surface 124. The widths of the first step surface 122, the second step surface 124, and the third step surface 126 (i.e., the size in the direction from the first side beam 11 to the second side beam 12) can be specified as required.

[0057] In the embodiment of the present application, the spacing between the first side beam 11 and the second side beam 12 may be specified based on different requirements of different vehicle models, the length of the connecting beam and the attachment beam (i.e., the size in the direction from the first side beam 11 to the second side beam 12) may be specified as required, and the width of the cavity hole 15 may be specified as required. For example, the extension direction of the first side beam 11 and the second side beam 12 is the length direction of the tray 10, and the direction from the first side beam 11 to the second side beam 12 is the width direction of the tray 10. When applied to some vehicle models, the spacing between the first side beam 11 and the second side beam 12 is specified to be relatively short so that the width of the tray 10 is less than the length of the tray 10 and the width of the cavity hole 15 is less than the length of the cavity hole 15, and when applied to other vehicle models, the spacing between the first side beam 11 and the second side beam 12 is increased so that the width of the tray 10 is equal to or greater than the length of the tray 10 and the width of the cavity hole 15 is equal to or greater than the length of the cavity hole 15.

[0058] The spacing between the first side beam 11 and the second side beam 12 can be adjusted as required, and the span between the stages at each level on the first side beam 11 and the second side beam 12 can be adjusted as required. In other words, the spacing between the first stage 121 of the first side beam 11 and the first stage 121 of the second side beam 12 can be adjusted so that the width of the corresponding first cooling plate 21 can be adjusted and the size of the first layer of battery cells can be adjusted, and the spacing between the second stage 123 of the first side beam 11 and the second stage 123 of the second side beam 12 can be adjusted so that the width of the corresponding second cooling plate 22 can be adjusted and the size of the second layer of battery cells can be adjusted. Therefore, the spacing between the first side beam 11 and the second side beam 12 can be adjusted based on various vehicle models, so that adaptability is strong.

[0059] Therefore, simple adjustments can be made for various vehicle models to meet the battery pack requirements of various vehicle models. For example, for a small vehicle, the spacing between the first side beam 11 and the second side beam 12 can be specified to be relatively short so that the sizes of the first layer of battery cells and the second layer of battery cells are relatively small, resulting in a relatively small battery capacity, thereby satisfying the power reserve requirements of a small-sized vehicle for short-distance transportation. For a medium-sized vehicle, the spacing between the first side beam 11 and the second side beam 12 can be specified to be longer so that the sizes of the first layer of battery cells and the second layer of battery cells are larger, resulting in a larger battery capacity, thereby satisfying the requirements for medium- and long-distance vehicle operation duration. For a large vehicle, the spacing between the first side beam 11 and the second side beam 12 can be specified to be even longer so that the sizes of the first layer of battery cells and the second layer of battery cells are even larger, resulting in a larger battery capacity, thereby satisfying the requirements for long-distance vehicle operation duration.

[0060] For a battery pack, the thermal management of the battery pack directly affects its performance. Therefore, through the arrangement of the first cold plate 21 and the second cold plate 22, in one embodiment, the first cold plate 21 plays a role in supporting the first layer of battery cells, and the second cold plate 22 plays a role in supporting the second layer of battery cells. In another embodiment, the first cold plate 21 can perform thermal management on the first layer of battery cells, and the second cold plate 22 can perform thermal management on the second layer of battery cells. Taking the thermal management performed by the first cold plate 21 on the first layer of battery cells as an example, the first cold plate 21 can heat the first layer of battery cells when the temperature of the first layer of battery cells is lower than the normal operating temperature, and can dissipate heat to cool the first layer of battery cells when the temperature of the first layer of battery cells is higher than the normal operating temperature. For the thermal management performed by the second cold plate 22 on the second layer of battery cells, please refer to the above description, and details will not be described again. Therefore, the battery pack has excellent thermal management capabilities to ensure reliable and stable operation.

[0061] Therefore, based on the battery pack and battery pack housing provided in the embodiments of the present application, a tray 10 including a first lateral beam 11 and a second lateral beam 12 is arranged, m stages 121 are separately arranged on each of the opposing sides of the first lateral beam 11 and the second lateral beam 12, n layers of cooling plates are arranged on the corresponding stages, and each layer of cooling plates is used to arrange a layer of battery cells, the n layers of battery cells are arranged in one tray 10, and the n layers of cooling plates perform thermal management, so that the battery pack operates reliably and stably. Compared with existing solutions in which multiple battery packs are stacked to form a whole, the battery pack in the embodiments of the present application has a compact structure, a small volume, and is easy to use in practice.

[0062] Optionally, referring to FIG. 4 , the size of the (n−1)th layer of the cooling plate is smaller than the size of the nth layer of the cooling plate in the direction from the first side beam 11 to the second side beam 12. Optionally, the direction from the first side beam 11 to the second side beam 12 is the width direction of the first cooling plate 21 and the second cooling plate 22, and the width of the first cooling plate 21 is smaller than the width of the second cooling plate 22. Therefore, the first cooling plate 21 can be attached and fixed to the first stage 121 of the first side beam 11 and the second side beam 12 to perform a supporting role, and the second cooling plate 22 can be attached and fixed to the second stage 123 of the first side beam 11 and the second side beam 12 to perform a supporting role. On the other hand, the second cooling plate 22 has a larger width so that a larger heating area or heat dissipation area can be specified. Therefore, if the area occupied by the second layer of battery cells arranged on the second cooling plate 22 is larger than the area occupied by the first layer of battery cells on the first cooling plate 21, the thermal management requirements are still met.

[0063] Optionally, the first cooling plate 21 is any one of an air-cooled plate, a liquid-cooled plate, or a direct-cooled plate, and the second cooling plate 22 is any one of an air-cooled plate, a liquid-cooled plate, or a direct-cooled plate.

[0064] Specifically, the air cooling plate may be provided with a base plate and fins connected to the base plate, or the air cooling plate may have other structures, without limitation. A flow path may be arranged inside the liquid cooling plate, and openings may be formed on the surfaces of the tray 10 and the liquid cooling plate to communicate with the flow path, so that the coolant flows through the flow path and conducts heat from the battery cells to the outside. The direct cooling plate can achieve heat dissipation requirements by utilizing the phase-change heat absorption and heat dissipation properties of the material. It is understood that the first cooling plate 21 and the second cooling plate 22 may have a heating function, and the heating function may be realized by disposing a heating coil on the plate, injecting high-temperature liquid into the flow path, or other methods, without limitation.

[0065] The first cooling plate 21 and the second cooling plate 22 may be of the same type or different types, for example, but not limited to, the first cooling plate 21 and the second cooling plate 22 may be a combination of a liquid cooling plate and a direct cooling plate, or a combination of a liquid cooling plate and a liquid cooling plate.

[0066] The cooling plate is arranged to be any one of air cooling plate, liquid cooling plate or direct cooling plate so that the thermal management requirements can be met, and further, the above three kinds of cooling plate have mature technology and low cost.

[0067] Referring to Figures 1 and 2, the first layer of battery cells includes a plurality of first battery cells 31 spaced apart from one another, and the second layer of battery cells includes a plurality of second battery cells 32 spaced apart from one another.

[0068] 4 , in the direction from the first side beam 11 to the second side beam 12, the size of the (n−1)th layer of battery cells is smaller than the size of the nth layer of battery cells. Optionally, the direction from the first side beam 11 to the second side beam 12 is the length direction of the first battery cell 31 and the second battery cell 32, and the length of the (n−1)th layer of battery cells is less than the length of the nth layer of battery cells. For example, the length of the first battery cell 31 is less than the length of the second battery cell 32.

[0069] The various accompanying drawings of this application merely illustrate the approximate shape of battery cells in certain embodiments. It should be understood that the first battery cell 31 and the second battery cell 32 may be of any suitable type, and this is not a limitation of the embodiments of this application. The length of the first battery cell 31 is less than the length of the second battery cell 32, so that the capacity of the second battery cell 32 is greater than the capacity of the first battery cell 31, given the same battery cell type. With respect to the first layer of battery cells and the second layer of battery cells, given the same arrangement density, the capacity of the second layer of battery cells is greater than the capacity of the first layer of battery cells. In existing solutions for stacking multiple layers of battery packs, each layer of the battery pack uses a layer of battery cells so that the capacity of the multiple layers of battery cells after stacking is equal, i.e., multiple first layers of battery cells in the embodiments of this application are stacked. However, in the embodiment of the present application, the capacities of the various layers of battery cells are different, and the capacity of the second layer of battery cells is greater than the capacity of the first layer of battery cells, so that the overall battery capacity of the battery pack can be increased.

[0070] Optionally, at least two of the n layers of battery cells are of different types, specifically, different types may refer to different capacities such as small capacity battery cells or large capacity battery cells, different types may refer to different varieties such as lithium iron phosphate battery cells or ternary battery cells, and different types may refer to different shapes such as cylindrical battery cells, rectangular housing battery cells, or soft pack battery cells.

[0071] The first and second side beams 11 and 12 are provided with first and second stages 121 and 123, respectively. The span between the two first stages 121 is less than the span between the two second stages 123. The width of the first cooling plate 21 is less than the width of the second cooling plate 22. As a result, the second cooling plate 22 cannot be attached to the two first stages 121 due to interference, thereby avoiding assembly errors. Meanwhile, the length of the first battery cell 31 is less than the length of the second battery cell 32. When the spacing distance between the end surfaces of the two battery cells in the length direction and the spacing distance between the side beams are the same, the length of the second battery cell 32 may be greater than the span between the first stages 121, i.e., greater than the width of the cavity hole 15. Therefore, the space created by forming the second step 123 on the lateral beam is efficiently utilized, a more compact structure is obtained, the space is more fully utilized, and therefore the energy density of the battery pack can be improved.

[0072] It should be understood that the span between two first steps 121 is the distance between the side surface (surface facing the second side beam 12) of the first step 121 of the first side beam 11 and the side surface (surface facing the first side beam 11) of the first step 121 of the second side beam 12, the span also being the width of the cavity hole 15, and the span between two second steps 123 is the distance between the side surface (surface facing the second side beam 12) of the second step 123 of the first side beam 11 and the side surface (surface facing the first side beam 11) of the second step 123 of the second side beam 12. The span between two third steps 125 is similar and will not be described in detail.

[0073] The width of the first cooling plate 21 is greater than the span between the two first stages 121 and equal to or less than the span between the two second stages 123 so that the first cooling plate 21 can be attached and fixed to the two first stages 121 without interfering with the second stages 123. When the width of the first cooling plate 21 is equal to the span between the two second stages 123, the two end surfaces of the first cooling plate 21 in the width direction abut against the side surfaces of the two second stages 123, respectively, and the first cooling plate 21 can prevent the first side beam 11 and the second side beam 12 from being attracted to each other.

[0074] The width of the second cooling plate 22 is greater than the span between the two second stages 123 and equal to or less than the span between the two third stages 125 so that the second cooling plate 22 can be attached and fixed to the two second stages 123 without interfering with the third stages 125. When the width of the second cooling plate 22 is equal to the span between the two third stages 125, the two end surfaces of the second cooling plate 22 in the width direction abut against the side surfaces of the two third stages 125, respectively, and the second cooling plate 22 can also prevent the first side beam 11 and the second side beam 12 from being attracted to each other.

[0075] The length of the first battery cell 31 is less than or equal to the width of the first cooling plate 21, and the orthogonal projection of the first layer of battery cells formed by the multiple first battery cells 31 on the first cooling plate 21 is entirely contained within the first cooling plate 21 and does not extend beyond the first cooling plate 21, so that the first cooling plate 21 can efficiently perform thermal management for the first layer of battery cells.

[0076] The length of the second battery cells 32 is less than or equal to the width of the second cooling plate 22, and the orthogonal projection of the second layer of battery cells formed by the multiple second battery cells 32 on the second cooling plate 22 is entirely contained within the second cooling plate 22 and does not extend beyond the second cooling plate 22 so that the second cooling plate 22 can efficiently perform thermal management for the second layer of battery cells.

[0077] In one embodiment, the surface of the second cooling plate 22 facing away from the second layer of battery cells contacts the first battery cells 31, i.e., the distance between the first step surface 122 and the second step surface 124 is equal to the total thickness of the first cooling plate 21 and the first layer of battery cells, so that the second cooling plate 22 can further provide thermal management for the first layer of battery cells.

[0078] Optionally, referring to Figures 2 and 4, the first cooling plate 21 is fixed to the first sections 121 of the first and second side beams 11 and 12 by welding using a welding rod. Specifically, a first welding rod 51 may be disposed on the first sections 121 of the first and second side beams 11 and 12, and the first cooling plate 21 is fixed to the two first sections 121 by high-temperature melting of the first welding rod 51. A specific welding process may be, for example, but is not limited to, laser welding. The welding rod extends approximately along the length of the first side beam 11 to achieve welding fixation at each position.

[0079] Optionally, referring to Figures 2 and 4, a second welding rod 52 can be placed on the two second stages 123, and the second cooling plate 22 is fixed to the two second stages 123 by the second welding rod 52.

[0080] Further optionally, the first cooling plate 21 is fixed to the first stage 121 of the first lateral beam 11 and the second lateral beam 12 by bonding with an adhesive tape. The adhesive tape may be, but is not limited to, a structural adhesive, a thermally conductive adhesive, etc.

[0081] Further optionally, the second cooling plate 22 may also be fixed to the two second stages 123 by bonding with adhesive tape.

[0082] It can be understood that the first cooling plate 21 and the second cooling plate 22 can be attached and fixed to the first lateral beam 11 and the second lateral beam 12 by the same process or different processes. Besides the process provided in the above embodiment, any other suitable process may also be utilized, which is not limited thereto.

[0083] In one embodiment, referring to FIGS. 2 and 4, at least one of the first side beam 11, the second side beam 12, and the connecting beam 13 is provided with an explosion-proof valve (not shown in the drawings). Specifically, the two ends of the connecting beam 13 are connected to the same ends of the first side beam 11 and the second side beam 12 in the longitudinal direction, respectively. FIGS. 2 and 4 show that a vent hole 131 is formed in the connecting beam 13, and an explosion-proof valve is disposed on the connecting beam 13 to close the vent hole 131. There may be multiple vent holes 131. In FIGS. 2 and 4, two vent holes 131 are shown. Accordingly, there may be multiple explosion-proof valves. In FIG. 4, two explosion-proof valves are shown. Optionally, the ventilation holes 131 may also be formed in the first side beam 11 or the second side beam 12, and corresponding explosion-proof valves may also be disposed on the first side beam 11 or the second side beam 12. It should be understood that the explosion-proof valves may be disposed on one, two, or three of the first side beam 11, the second side beam 12, and the connecting beam 13, and this is not limited thereto. FIG. 4 shows that the explosion-proof valves 16 are disposed on the ventilation holes 131.

[0084] By using the explosion-proof valve, when the battery cells generate gas due to thermal runaway and the gas pressure in the tray 10 rises rapidly to a threshold value, the gas can be released through the explosion-proof valve to avoid accidents such as explosions.

[0085] A battery cell control member 33 may be disposed on the mounting beam 14 at the other end of the first side beam 11 and the second side beam 12 in the longitudinal direction. The battery cell control member 33 is configured to be electrically connected to the plurality of first battery cells 31 and the plurality of second battery cells 32 to manage charging and discharging of the battery cells. Each layer of battery cells may use one battery cell control member 33, or multiple layers of battery cells may share one battery cell control member 33, and this is not limited thereto. The specific structure, control principle, and other characteristics of the battery cell control member 33 are not limited in the embodiments of the present application.

[0086] 1, 2, and 4, the battery pack housing further includes a thermal protection member configured to be disposed between two battery cells in at least one layer of the battery cells. Optionally, the thermal protection member includes a first thermal protection member 41 and a second thermal protection member 42. The first thermal protection member 41 is disposed between the plurality of first battery cells 31, and the second thermal protection member 42 is disposed between the plurality of second battery cells 32. The first thermal protection member 41 and the second thermal protection member 42 are disposed between adjacent battery cells, i.e., the first thermal protection member 41 is disposed between any two adjacent first battery cells 31 in the plurality of first battery cells 31, and the second thermal protection member 42 is disposed between any two adjacent second battery cells 32 in the plurality of second battery cells 32. There may be a plurality of first battery cells 31. The first thermal protection members 41 may be arranged between every two adjacent first battery cells 31, or the first thermal protection members 41 may be arranged between every two first battery cells 31. Of course, other arrangements may exist, and this is not limited thereto. It can be understood that the multiple first thermal protection members 41 are arranged as uniformly as possible in the multiple battery cells in the first layer of battery cells in order to achieve a relatively uniform thermal protection effect at each position in the first layer of battery cells. For the arrangement of the multiple second thermal protection members 42, please refer to the above description, and details will not be described again.

[0087] The first thermal protection member 41 and the second thermal protection member 42 serve to guide the heat generated in the battery cells out as quickly as possible to prevent heat accumulation from causing thermal runaway of the battery cells. Based on the thermal management performed by the first cooling plate 21 and the second cooling plate 22, the use of the first thermal protection member 41 and the second thermal protection member 42 can enhance the thermal management level of the battery pack, so that the battery pack is more stable and reliable.

[0088] Optionally, referring to FIG. 1 , the first thermal protection member 41 includes at least one of a thermally conductive layer 411, a heat absorbing layer 412, and a thermally insulating layer 413 that are stacked together, and / or the second thermal protection member 42 includes at least one of a thermally conductive layer 411, a heat absorbing layer 412, and a thermally insulating layer 413 that are stacked together.

[0089] 1 shows that the first thermal protection member 41 includes a thermally conductive layer 411, a thermal absorption layer 412, and a thermal insulation layer 413, which are stacked one on the other. It should be understood that the first thermal protection member 41 may also be one, two, or three of the thermally conductive layer 411, the heat absorption layer 412, and the thermal insulation layer 413, and is not limited thereto. The thermally conductive layer 411 serves to conduct heat from the first battery cell 31 to the outside, the heat absorption layer 412 serves to absorb heat, and the thermal insulation layer 413 serves to insulate heat, thereby reducing the mutual thermal influence between adjacent first battery cells 31.

[0090] The first thermal protection member 41 may be connected to the first lateral beam 11 and / or the second lateral beam 12, and the first thermal protection member 41 can guide heat to the first lateral beam 11 or the second lateral beam 12 to achieve heat dissipation.

[0091] 1 , the operation process of the laminated thermal conduction layer 411, the heat absorption layer 412, and the thermal insulation layer 413 of the first thermal protection member 41 is as follows: to reduce the thermal impact of the first battery cell 31 on other battery cells, the heat emitted by the first battery cell 31 is guided to the heat absorption layer 412 by the thermal conduction layer 411, which has a relatively large thermal conductivity coefficient. The heat is absorbed after entering the heat absorption layer 412, and finally, less heat is transferred to the thermal insulation layer 413 for dissipation. Therefore, the effect of reducing the thermal load and absorbing heat layer by layer is achieved. It can be understood that the first thermal protection member 41 may be one, two, or three of the thermal conduction layer 411, the heat absorption layer 412, and the thermal insulation layer 413, or may have a structure with more other functional layers, without being limited thereto.

[0092] For the structure of the second thermal protection member 42, please refer to the above description of the first thermal protection member 41, and the details will not be described again. Figure 1 shows an embodiment in which the second thermal protection member 42 has only one heat absorption layer 412.

[0093] Optionally, the heat absorption layer 412 is made of a phase-change heat absorption material. The phase-change heat absorption material may be any suitable phase-change material. The principle of the phase-change material is as follows: the phase-change material absorbs heat by absorbing heat and causing a chemical complex reaction to create a new substance. Therefore, the above-mentioned purpose of transferring less heat to the thermal insulation layer 413 for release is achieved.

[0094] Optionally, referring to Figures 2 and 4, adhesive slots 127 are formed in the tops of the first and second side beams 11, 12, respectively, and the adhesive slots 127 are configured to be filled with adhesive (not shown in the drawings). Referring to Figures 1, 2, and 4, the battery pack housing further includes a cover plate 60, which covers the tops of the first and second side beams 11, 12, and is bonded to the adhesive in the adhesive slots 127.

[0095] Adhesive slots 127 are formed in the third step surface 126 and may also be formed in the connecting beam 13 and the mounting beam 14. The adhesive slots 127 are formed to accommodate adhesive so that the gap between the cover plate 60 and the third step surface 126 is smaller, thus reducing the thickness of the battery pack and improving sealing.

[0096] The cover plate 60 may be made of a composite material and has advantages such as easy machining, relatively good overall flatness, good placement, easy assembly, good structural stability, and good appearance. Optionally, the cover plate 60 is made of a material with low thermal conductivity to have a better insulating effect. Optionally, the cover plate 60 may also be attached and fixed to the tray 10 by fasteners such as screws, but this is not limited thereto. Optionally, a third welding rod 53 may be disposed on the third step surface 126, and the cover plate 60 is fixed to the third step surface 126 by the third welding rod 53. For the placement of the third welding rod 53, please refer to the above description of the first welding rod 51 and the second welding rod 52, and the details will not be described again in this specification.

[0097] Optionally, referring to Figures 1, 2 and 4, raised snap walls 128 are further disposed on the top edges of the first and second side beams 11, 12, and the periphery of the cover plate 60 is snapped into the snap walls 128.

[0098] Taking the snap wall 128 arranged on the second side beam 12 as an example, the snap wall 128 is arranged on the third step surface 126, extends along the length of the second side beam 12, and is flush with the side surface of the second side beam 12 facing away from the first side beam 11. See the above description for the snap wall 128 on the first side beam 11. It can be understood that the snap wall 128 may also be arranged on the connecting beam 13 and the mounting beam 14. The snap wall 128 serves to position and limit the cover plate 60.

[0099] 1, 2, and 4, the battery pack housing further includes an insulating layer 70 and a bottom plate 80. The insulating layer 70 is disposed on one side of the first cooling plate 21 (first layer of cooling plate) facing away from the second cooling plate 22 (second layer of cooling plate). The bottom plate 80 is disposed on one side of the insulating layer 70 facing away from the first cooling plate 21, and the bottom plate 80 is fixed to the first lateral beam 11 and the second lateral beam 12.

[0100] The insulating layer 70 contacts the surface of the first cooling plate 21 facing away from the first layer of the battery cells through the cavity holes 15, thereby realizing a thermal insulation effect for the first cooling plate 21. The insulating layer may be, but is not limited to, insulating cotton or the like. By using the insulating layer 70, the first cooling plate 21 is kept at a normal operating temperature, thereby avoiding adverse effects on the first layer of the battery cells caused by temperature loss.

[0101] The bottom plate 80 is connected to the first side beam 11 and the second side beam 12 to close the tray 10 and form a stable structure of the tray 10. The bottom plate 80 has a roughly flat plate shape, and the inside of the bottom plate 80 may be hollowed out to some extent. The cross-sectional shape of the hollowed-out position may be a triangle or the like, but is not limited thereto.

[0102] As shown in Figure 5, an embodiment of the present application further provides an electric device including the battery pack according to the above-mentioned embodiment. The electric device may be, but is not limited to, an electric vehicle, a household electric device, etc.

[0103] The electric device in the embodiment of the present application uses the battery pack in the embodiment of the present application, and the battery pack uses the battery pack housing in the embodiment of the present application. The tray 10 includes a first lateral beam 11 and a second lateral beam 12. m stages 121 are separately arranged on opposite sides of the first lateral beam 11 and the second lateral beam 12. n layers of cooling plates are arranged on the corresponding stages, each layer of the cooling plates being used to arrange a layer of battery cells. The n layers of battery cells are arranged in one tray 10, and the n layers of cooling plates perform thermal management to ensure reliable and stable operation of the battery pack. Compared to existing solutions that stack multiple battery packs to form a whole, the battery pack in the embodiment of the present application has a compact structure, a small volume, and is easy to use.

[0104] It should be noted that in describing the embodiments of the present application, the orientations or positional relationships of terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" are orientations or positional relationships based on the accompanying drawings, and are intended merely to facilitate the explanation and simplicity of the present application, and do not indicate or imply that the referenced devices or components must have a particular orientation or be configured and operated based on a particular orientation, and therefore cannot be understood as limitations on the present application.

[0105] The above disclosure is merely a preferred embodiment of the present application, and naturally cannot be used to limit the scope of the rights of the present application. A person skilled in the art can understand all or part of the process for implementing the above embodiment, and the equivalent modifications made according to the claims of the present application still fall within the scope covered by the present application. [Explanation of symbols]

[0106] 10 trays 11 First side beam 12 Second side beam 121 First paragraph 122 First step surface 123 Second Section 124 Second step surface 125 Third Section 126 Third Stage Surface 127 adhesive slots 128 Snap Wall 13 Connecting beams 131 Ventilation hole 14 Mounting beam 15 Cavity 16 Explosion-proof valve 21 First cooling plate 22 Second cooling plate 31 First battery cell 32 Second Battery Cell 33 Battery cell control components 41 First thermal protection member 411 Thermal Conduction Layer 412 Heat absorption layer 413 Thermal insulation layer 42 Second thermal protection member 51 First welding rod 52 Second welding rod 53 Third welding rod 60 Cover plate 70 Insulation Layer 80 Bottom plate

Claims

1. a tray (10) having a first side beam (11) and a second side beam (12) opposite to each other, wherein m stages are separately arranged on each of the opposite sides of the first side beam (11) and the second side beam (12), m≧3, and the m stages are numbered in ascending order from the bottom to the top of the first side beam (11); n layers of cooling plates, two opposite ends of the n layers of cooling plates being arranged on corresponding stages of the first side beam (11) and the second side beam (12), each layer of cooling plates corresponding to one stage, each layer of cooling plates being used for arranging layers of battery cells, 2≦n≦m, and the n layers of cooling plates being numbered in ascending order from the bottom to the top of the first side beam (11); Equipped with In a direction from the first side beam (11) to the second side beam (12), a size of the (n-1)th layer of the cooling plate is smaller than a size of the nth layer of the cooling plate.

2. 2. The battery pack housing according to claim 1, wherein the cooling plate is fixed to the stages of the first side beam (11) and the second side beam (12) by welding using a welding rod, or the cooling plate is fixed to the stages of the first side beam (11) and the second side beam (12) by bonding using an adhesive tape.

3. 3. The battery pack housing of claim 1, wherein adhesive slots (127) are formed in the tops of the first and second side beams (11) and (12), respectively, and the adhesive slots (127) are configured to be filled with adhesive, and the battery pack housing further comprises a cover plate (60), which covers the tops of the first and second side beams (11) and (12) and is bonded to the adhesive in the adhesive slots (127).

4. 4. The battery pack housing of claim 3, wherein raised snap walls (128) are further disposed on the top edges of the first side beam (11) and the second side beam (12), and the periphery of the cover plate (60) snaps into the snap walls (128).

5. 5. The battery pack housing according to claim 1, wherein ends of the first side beam (11) and the second side beam (12) in the length direction are further connected to a connecting beam (13), and at least one of the first side beam (11), the second side beam (12), and the connecting beam (13) is provided with an explosion-proof valve (16).

6. 6. The battery pack housing of claim 5, wherein the other ends of the first and second side beams in the length direction are further connected to an attachment beam, and the connecting beam and the attachment beam are configured to attach and secure the first side beam to the second side beam.

7. 7. The battery pack housing of claim 6, wherein a battery cell control member (33) is disposed on the mounting beam (14), the battery cell control member (33) being configured to electrically connect to the battery cells.

8. 8. The battery pack housing of claim 1, further comprising an insulating layer (70) and a bottom plate (80), wherein the insulating layer (70) is disposed on one side of the first cooling plate layer (21) facing away from the second cooling plate layer (22), the bottom plate (80) is disposed on one side of the insulating layer (70) facing away from the first cooling plate layer (21), and the bottom plate (80) is fixed to the first side beam (11) and the second side beam (12).

9. 9. The battery pack housing according to claim 1, wherein the height of the (m-1)th step relative to the (m-2)th step is equal to or greater than the total height of the (n-2)th layer of the cooling plate and the (n-2)th layer of the battery cells.

10. 10. The battery pack housing of claim 1, wherein the cooling plate is one of an air cooling plate, a liquid cooling plate, or a direct cooling plate.

11. 11. The battery pack housing of claim 1, further comprising a thermal protection member, the thermal protection member configured to be disposed between two battery cells of at least one layer of battery cells.

12. 12. The battery pack housing of claim 11, wherein the thermal protection member comprises at least one of a thermally conductive layer (411), a heat absorbing layer (412), and a thermally insulating layer (413) laminated together.

13. 13. The battery pack housing of claim 12, wherein the heat absorption layer (412) is made of a phase change heat absorption material.

14. A battery pack comprising: a battery cell; and the battery pack housing according to any one of claims 1 to 13, wherein the battery cell is disposed on a cooling plate of the battery pack housing.

15. 15. The battery pack of claim 14, wherein a plurality of battery cells are provided and divided into n layers, a layer of the battery cells being disposed on each layer of the cooling plate.

16. 16. The battery pack of claim 15, wherein a size of the (n-1)th layer of battery cells is smaller than a size of the nth layer of battery cells in a direction from the first side beam (11) to the second side beam (12).

17. 16. The battery pack of claim 15, wherein the direction from the first side beam (11) to the second side beam (12) is a length direction of the battery cells, and the length of the (n-1)th layer of battery cells is less than the length of the nth layer of battery cells.

18. 16. The battery pack of claim 15, wherein at least two of the n layers of battery cells are of different types.

19. An electric device comprising a battery pack according to any one of claims 14 to 18.

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