Battery Pack

Abstract

The present application provides a battery pack, including a battery cell stack; a liquid cooling assembly, the liquid cooling assembly including a liquid cooling plate, a liquid inlet joint and a liquid outlet joint, the liquid cooling plate is in contact with the battery cell stack for heat exchange, the liquid inlet joint and the liquid outlet joint are respectively connected to the liquid cooling plate, wherein the number of the liquid inlet joint and the liquid outlet joint is an odd number, and the number of the other is an even number. For the battery pack provided by the present application, regardless of whether the number of the liquid inlet joints is an even number or the number of the liquid outlet joints is an even number, the liquid cooling assembly can form at least two parallel heat exchange circuits, and the heat exchange medium will flow through different areas of the battery cell stack at the same time when flowing in at least two heat exchange circuits, which helps to make the heat exchange effect of the heat exchange medium on different areas of the battery cell stack tend to be the same, helps to make the temperature of different areas of the battery cell stack more uniform, and the corresponding battery pack has better temperature uniformity.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a battery pack. Background Art

[0002] The battery pack can store electrical energy to power electrical devices when needed. Generally, the battery pack needs to keep the battery stack within a preset temperature range when in use. In order to adjust the temperature of the battery stack, different flowable media (such as air or liquid) are used as heat exchange media to exchange heat with the battery stack.

[0003] In the related art, the heat exchange medium flows from one side of the battery stack to the other side to achieve heat exchange for the entire battery stack. However, the heat exchange effect of the heat exchange medium on the battery stack will continue to decrease along the flow direction, which makes the temperature consistency of different areas of the battery stack poor. Therefore, a battery pack with better temperature uniformity is urgently needed. Utility Model Content

[0004] In view of this, the purpose of the present application is to provide a battery pack.

[0005] Based on the above-mentioned purpose, the first aspect of the present application provides a battery pack, comprising: a battery cell stack; a liquid cooling assembly, the liquid cooling assembly comprising a liquid cooling plate, a liquid inlet connector and a liquid outlet connector, the liquid cooling plate is in contact with the battery cell stack for heat exchange, the liquid inlet connector and the liquid outlet connector are respectively connected to the liquid cooling plate, wherein the number of one of the liquid inlet connector and the liquid outlet connector is odd, and the number of the other is even.

[0006] Optionally, the number of the liquid inlet connectors is one, and the number of the liquid outlet connectors is two.

[0007] Optionally, the battery cell stack includes at least two battery cell groups arranged along a first direction, each of the battery cell groups includes a plurality of battery cells arranged along a second direction; the first direction and the second direction intersect; there are multiple liquid cooling plates, and the multiple liquid cooling plates include a liquid inlet cold plate connected to the liquid inlet joint, and a liquid outlet cold plate connected to the liquid outlet joint; the liquid inlet cold plate is located between adjacent battery cell groups, and the liquid outlet cold plates are located on both sides of the battery cell stack along the first direction, and the liquid outlet cold plates are connected to the liquid inlet cold plates.

[0008] Optionally, two liquid inlet cold plates are provided and arranged at intervals along the first direction, and one liquid outlet cold plate is provided on two relatively outer sides of the two liquid inlet cold plates respectively; one liquid inlet joint is connected to the two liquid inlet cold plates respectively, and two liquid outlet joints are connected to the two liquid outlet cold plates one by one.

[0009] Optionally, each of the battery cell groups includes two end plates spaced apart along the second direction, and the multiple battery cells are located between the two end plates; the liquid cooling plate is connected to the corresponding end plate via fasteners; and the portion of the fastener located outside the end plate is arranged inside the liquid cooling plate.

[0010] Optionally, each of the liquid cooling plates includes a main body, and two current collectors respectively installed at both ends of the main body along the second direction, the main body is connected to the liquid inlet joint or the liquid outlet joint through the current collector, and the fastener passes through the current collector and is connected to the corresponding end plate.

[0011] Optionally, a sinker is provided on the surface of one side of the current collector away from the corresponding end plate, and a connecting through hole is provided in the middle of the sinker; the fastener includes a connecting portion passing through the connecting through hole, and an abutting portion connected to the connecting portion; the radial cross-sectional diameter of the abutting portion is larger than the radial cross-sectional diameter of the connecting portion, and the abutting portion is located in the sinker and abuts against the bottom of the sinker.

[0012] Optionally, a connecting layer is provided between the main body and the battery cell group, and the multiple battery cells of the battery cell group are connected to the main body through the connecting layer; a limiting structure is provided on the side wall of the end plate close to the current collector, and the current collector abuts against the limiting structure to define a spacing space between the battery cell and the main body; the spacing space is used to limit the thickness of the connecting layer.

[0013] Optionally, the thickness of the main body is smaller than the thickness of the current collector, and a groove is provided on a side wall of the end plate close to the current collector, and the groove is configured as the limiting structure.

[0014] Optionally, a pipeline connecting portion is provided on a side of the current collector away from the main body, the pipeline connecting portion extends out of the end plate along the second direction, and the liquid inlet connector or the liquid outlet connector is connected to the pipeline connecting portion.

[0015] Optionally, each of the current collectors is provided with a pipeline connecting portion, and in the same liquid cooling plate, along a third direction, two pipeline connecting portions are respectively close to opposite sides of the liquid cooling plate; the third direction is respectively perpendicular to the first direction and the second direction.

[0016] From the above, it can be seen that for the battery pack provided in the present application, regardless of the number of liquid inlet connectors or the number of liquid outlet connectors being an even number, the liquid cooling assembly can form at least two parallel heat exchange circuits, and the heat exchange medium will simultaneously flow through different areas of the battery cell stack when flowing in at least two heat exchange circuits, which helps to make the heat exchange effect of the heat exchange medium on different areas of the battery cell stack tend to be the same, helps to make the temperature of different areas of the battery cell stack more uniform, and the corresponding battery pack has better temperature uniformity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1a A three-dimensional schematic diagram of a battery pack of the first structure according to an embodiment of the present application;

[0019] Figure 1b A three-dimensional schematic diagram of a battery pack of the second structure according to an embodiment of the present application;

[0020] Figure 2 An exploded schematic diagram of a battery pack of the first structure according to an embodiment of the present application;

[0021] Figure 3 A schematic diagram of the flow direction of the heat exchange medium in a plurality of liquid cooling plates of a battery pack of the first structure according to an embodiment of the present application;

[0022] Figure 4 A partial top view schematic diagram of a battery pack of the first structure according to an embodiment of the present application;

[0023] Figure 5 This is a three-dimensional schematic diagram of a battery pack of the first structure of an embodiment of the present application with the box body removed;

[0024] Figure 6 for Figure 5 A magnified schematic diagram of part A;

[0025] Figure 7 A schematic side view of a battery pack of the first structure of an embodiment of the present application with the box body removed;

[0026] Figure 8 for Figure 7 Schematic diagram of the cutaway of the middle BB section;

[0027] Fig. 9 for Figure 8 The enlarged schematic diagram of the D part;

[0028] Fig.10 for Figure 7 Schematic diagram of the cutaway of the CC section;

[0029] Fig.11 for Fig.10 Enlarged schematic diagram of part E in the middle.

[0030] Description of reference numerals:

[0031] 100, battery cell stack; 10, battery cell group; 1, battery cell; 2, end plate; 201, limiting structure;

[0032] 200, liquid cooling assembly; 210, liquid cooling plate; 211, liquid inlet cold plate; 212, liquid outlet cold plate; 213, main body; 214, current collector; 2141, sink; 2142, connecting through hole; 215, pipeline connecting part; 220, liquid inlet joint; 230, liquid outlet joint; 240, fastener; 241, connecting part; 242, abutting part; 250, connecting layer;

[0033] 300. Cabinet. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0035] It should be noted that the relative arrangement of the components, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise.

[0036] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0037] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0038] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0039] In the related art, an existing liquid cooling plate is used to exchange heat for an existing battery cell stack. When the existing battery cell stack needs to be cooled, a liquid with a lower temperature is injected into the existing liquid cooling plate; when the existing battery cell stack needs to be heated, a liquid with a higher temperature is injected into the existing liquid cooling plate. The following is a further explanation using the cooling of an existing battery cell stack as an example.

[0040] Combined with the content in the background technology, it can be learned that when the coolant flows unidirectionally from one side of the existing battery stack to the other side in the existing liquid cooling plate, the temperature of the coolant is low when it first enters the existing liquid cooling plate, but the coolant continuously exchanges heat with different areas of the existing battery stack during the flow in the existing liquid cooling plate, and the temperature of the coolant itself is constantly increasing, and the cooling effect on different areas of the existing battery stack is constantly decreasing. When the volume of the existing battery stack is large, the temperature difference between the area of ​​the existing battery stack close to the liquid inlet of the existing liquid cooling plate and the area close to the liquid outlet of the existing liquid cooling plate is large, which affects the cycle life of the battery pack.

[0041] In view of this, if Figure 1a , Figure 1a The three-dimensional schematic diagram of the battery pack of the first structure provided by the embodiment of the present application is shown. The battery pack includes: a battery cell stack 100; a liquid cooling assembly 200, the liquid cooling assembly 200 includes a liquid cooling plate 210, a liquid inlet joint 220 and a liquid outlet joint 230, the liquid cooling plate 210 is in contact with the battery cell stack 100 for heat exchange, and the liquid inlet joint 220 and the liquid outlet joint 230 are respectively connected to the liquid cooling plate 210, wherein the number of one of the liquid inlet joint 220 and the liquid outlet joint 230 is an odd number, and the number of the other is an even number.

[0042] Exemplarily, the liquid cooling assembly 200 includes one, two or more liquid cooling plates 210. When the liquid cooling assembly 200 includes at least two liquid cooling plates 210, the at least two liquid cooling plates 210 may be connected to each other.

[0043] Exemplarily, when the liquid cooling assembly 200 includes at least two liquid cooling plates 210 , the liquid inlet connector 220 and the liquid outlet connector 230 may be connected to the same liquid cooling plate 210 , or may be connected to different liquid cooling plates 210 , respectively.

[0044] Exemplarily, when the liquid cooling assembly 200 includes at least two liquid cooling plates 210 , the same liquid inlet connector 220 or the same liquid outlet connector 230 can be connected to different liquid cooling plates 210 , respectively.

[0045] exist Figure 1a In the illustrated battery pack, the number of the liquid inlet connectors 220 is an odd number (e.g., one), and the number of the liquid outlet connectors 230 is an even number (e.g., two). Figure 1b , Figure 1b A three-dimensional schematic diagram of a battery pack of the second structure provided in an embodiment of the present application is shown. Figure 1b In the battery pack shown, the number of the liquid inlet connectors 220 is an even number (eg, two), and the number of the liquid outlet connectors 230 is an odd number (eg, one).

[0046] In this embodiment, no matter the number of the liquid inlet connectors 220 is an even number or the number of the liquid outlet connectors 230 is an even number, the liquid cooling assembly 200 can form at least two parallel heat exchange circuits. Figure 1a , when the number of the liquid outlet connectors 230 is an even number, the heat exchange medium in the liquid cooling assembly 200 will flow to at least two liquid outlet connectors 230 at the same time, thereby forming at least two heat exchange loops matching the number of the liquid outlet connectors 230. Figure 1b When the number of the liquid inlet connectors 220 is an even number, the heat exchange medium in the liquid cooling assembly 200 will flow into the liquid cooling plate 210 from at least two liquid inlet connectors 220 at the same time, thereby forming at least two heat exchange loops matching the number of the liquid inlet connectors 220. Since the liquid cooling assembly 200 in the battery pack can form at least two heat exchange loops, the heat exchange medium will flow through different areas of the battery cell stack 100 at the same time when flowing in at least two heat exchange loops, which helps to make the heat exchange effect of the heat exchange medium on different areas of the battery cell stack 100 tend to be the same, and helps to make the temperature of different areas of the battery cell stack 100 more uniform, and the corresponding battery pack has better temperature uniformity.

[0047] like Figure 1a In some embodiments, the number of the liquid inlet connector 220 is one, and the number of the liquid outlet connector 230 is two.

[0048] The heat exchange medium enters the liquid cooling plate 210 of the liquid cooling assembly 200 through the same liquid inlet joint 220, and the heat exchange medium flows to the two liquid outlet joints 230 in the liquid cooling plate 210 at the same time to form two heat exchange loops. The heat exchange medium flows synchronously in the two heat exchange loops, and synchronously exchanges heat with different areas of the battery cell stack 100 where the two heat exchange loops are located, and the heat exchange effect is roughly the same, further improving the temperature uniformity of different areas of the battery cell stack 100.

[0049] like Figure 1a The battery cell stack 100 includes a first direction (such as Figure 1a At least two battery cell groups 10 are arranged along the second direction (such as the X direction in FIG. 1 ), each battery cell group 10 includes Figure 1a A plurality of battery cells 1 are arranged in a Y direction (in the Y direction), and the first direction and the second direction intersect.

[0050] like Figure 2 , Figure 2 The exploded schematic diagram of the battery pack is shown. A plurality of liquid cooling plates 210 are provided, and the plurality of liquid cooling plates 210 include a liquid inlet cooling plate 211 connected to the liquid inlet connector 220, and a liquid outlet cooling plate 212 connected to the liquid outlet connector 230. The liquid inlet cooling plate 211 is located between adjacent battery cell groups 10, and the liquid outlet cooling plate 212 is located on both sides of the battery cell stack 100 along the first direction, and the liquid outlet cooling plate 212 is connected to the liquid inlet cooling plate 211.

[0051] like Figure 3 , Figure 3 The schematic diagram shows the flow direction of the heat exchange medium in the multiple liquid cooling plates 210. The heat exchange medium flows from the liquid inlet cooling plate 211 to the liquid outlet cooling plates 212 on both sides of the battery cell stack 100.

[0052] Exemplarily, when the battery cell 1 is a cylindrical battery cell, the angle between the first direction and the second direction may be an acute angle.

[0053] Exemplarily, when the battery cell 1 is a square shell battery cell, the first direction and the second direction are perpendicular to each other.

[0054] like Figure 1a In the embodiment of the present application, the battery cell 1 is a square shell battery cell. The thickness direction of the liquid cooling plate 210 is parallel to the first direction, the length direction of the liquid cooling plate 210 is parallel to the second direction, and the width direction of the liquid cooling plate 210 is parallel to the height direction of the battery cell 1.

[0055] Exemplarily, the width of the liquid cooling plate 210 is greater than the height of the battery cell 1 ; or, the width of the liquid cooling plate 210 is equal to the height of the battery cell 1 ; or, the width of the liquid cooling plate 210 is less than the height of the battery cell 1 .

[0056] For example, Figure 1aThe battery pack further includes a box body 300 with an opening at the top, and a receiving cavity connected to the opening is provided inside the box body 300. The battery cell stack 100 and the liquid cooling plate 210 are placed in the receiving cavity through the opening. A pole 101 is provided at the top of the battery cell 1, and the pole 101 faces the opening of the box body 300.

[0057] In this embodiment, cooling of the battery cell 1 in the battery pack by the liquid cooling plate 210 is taken as an example for further explanation. When the battery cell stack 100 includes at least two battery cell groups 10, the temperature of the side wall of the battery cell group 10 located in the middle of the battery cell stack 100 will be greater than the side wall of the battery cell group 10 located on the periphery of the battery cell stack 100. The coolant flows from the liquid inlet cold plate 211 to the liquid outlet cold plate 212, that is, the temperature of the coolant in the liquid inlet cold plate 211 will be lower than the temperature of the coolant in the liquid outlet cold plate 212. The liquid inlet cold plate 211 is arranged between adjacent battery cell groups 10, and the side wall of the battery cell group 10 with a higher temperature can be cooled by a coolant with a lower temperature; the liquid outlet cold plate 212 is arranged outside the battery cell stack 100, and the side wall of the battery cell group 10 with a relatively lower temperature can be cooled by a coolant with a relatively higher temperature, which helps to make the temperature in the middle and periphery of the battery cell stack 100 more uniform.

[0058] In the related art, the existing liquid cooling plate is usually located at the bottom of the existing battery cell stack, and the existing liquid cooling plate only contacts the bottom of the existing battery cell in the existing battery cell stack. When the height of the existing battery cell is large, this heat exchange method will cause a large temperature difference between the bottom and top of the existing battery cell, that is, the existing battery cell height gradient temperature difference is large.

[0059] In this embodiment, the liquid cooling plate 210 acts on the side wall of the battery cell group 10 to help reduce the temperature difference between the upper and lower parts of the battery cell 1 , that is, to help make the temperature of the upper and lower parts of the battery cell stack 100 more uniform.

[0060] like Figure 4 , Figure 4 A partial top view of a battery pack is shown. In some embodiments, two liquid inlet cold plates 211 are provided and arranged at intervals along the first direction, and two opposite outer sides of the two liquid inlet cold plates 211 are respectively provided with a liquid outlet cold plate 212; a liquid inlet connector 220 is respectively connected to the two liquid inlet cold plates 211, and two liquid outlet connectors 230 are connected to the two liquid outlet cold plates 212 in a one-to-one correspondence.

[0061] Exemplarily, one liquid inlet connector 220 may be connected to two liquid inlet cold plates 211 respectively through two branch pipes.

[0062] Exemplarily, the liquid inlet cold plate 211 and the corresponding liquid outlet cold plate 212 may be connected via a pipeline.

[0063] Exemplarily, each liquid outlet connector 230 and the corresponding liquid outlet cold plate 212 may also be connected via a pipeline.

[0064] For example, Figure 1a The liquid inlet connector 220 and the liquid outlet connector 230 can extend out of the box body 300 to facilitate connection with pipelines outside the box body 300.

[0065] Combination Figure 4 The structure and direction shown further illustrate the battery pack. The cell stack 100 includes three cell groups 10 distributed in the transverse direction, and each cell group 10 includes a plurality of cells 1 distributed in the longitudinal direction. In the same cell group 10, the side walls of adjacent cells 1 with larger areas are close to each other, and the side walls of the cells 1 with smaller areas are flush to form the side walls of the cell group 10. In the cell stack 100, the side walls of adjacent cell groups 10 are close to each other. The middle cell group 10 is located between two liquid inlet cold plates 211, and the edge cell group 10 is located between the liquid inlet cold plate 211 and the liquid outlet cold plate 212. In this embodiment, the two side walls of the middle cell group 10 are cooled by two liquid inlet cold plates 211 respectively. In each edge cell group 10, the side wall close to the center cell group 10 is cooled by the liquid inlet cold plate 211, and the side wall away from the center cell group 10 is cooled by the liquid outlet cold plate 212. Therefore, both side walls of each battery cell group 10 in the battery cell stack 100 can be cooled by the liquid cooling plate 210, which increases the cooling area of ​​each battery cell 1, helps to improve the cooling effect of the liquid cooling plate 210 on all battery cells 1, and enables the battery pack of this embodiment to support high-rate fast charging.

[0066] At the same time, the same liquid inlet cold plate 211 can cool the two battery cell groups 10 located on both sides thereof at the same time, which helps to reduce the number of liquid inlet cold plates 211 and reduce the cost of the battery pack.

[0067] It should also be noted that if Figure 3 , the coolant flowing in from the liquid inlet connector 220 can simultaneously enter the two liquid inlet cold plates 211, and the coolant in the two liquid inlet cold plates 211 simultaneously enters the adjacent liquid outlet cold plates 212 after flowing through their respective liquid inlet cold plates 211. In other words, Figure 3 Each liquid outlet cold plate 212 and the adjacent liquid inlet cold plate 211 can form a U-shaped cooling channel. The two cooling channels are symmetrical with respect to the liquid inlet connector 220. The coolant flows synchronously in the two cooling channels, which helps to further improve the temperature uniformity of the battery pack.

[0068] like Figure 5 , Figure 5 The 3D schematic diagram of the battery pack after removing the box 300 is shown. Each battery cell group 10 includes two end plates 2 spaced apart along the second direction, and a plurality of battery cells 1 are located between the two end plates 2. Figure 6 , Figure 6 Shown Figure 5 The enlarged schematic diagram of the A portion in the figure. The liquid cooling plate 210 is connected to the corresponding end plate 2 via a fastener 240 ; the portion of the fastener 240 located outside the end plate 2 is arranged inside the liquid cooling plate 210 .

[0069] Illustratively, in the same battery cell group 10 , the two end plates 2 are respectively in contact with the battery cells 1 at the head and the battery cells 1 at the tail.

[0070] For example, the fastener 240 may be a bolt or a rivet.

[0071] The liquid cooling plate 210 is connected to the end plate 2 via the fastener 240 , which can improve the connection reliability between the liquid cooling plate 210 and the end plate 2 and improve the overall mechanical strength of the battery pack.

[0072] Taking the fastener 240 as a bolt as an example, a portion of the threaded rod of the bolt is screwed into the end plate 2, and the other portion of the threaded rod and the nut are located outside the end plate 2. The portion of the bolt located outside the end plate 2 is entirely located inside the liquid cooling plate 210.

[0073] like Figure 6 Since the portion of the fastener 240 located outside the end plate 2 is arranged inside the liquid cooling plate 210, that is, this portion will not extend out of the liquid cooling plate 210 away from the surface of the corresponding end plate 2, then when the end plate 2 or other structural parts are also arranged on the surface of the liquid cooling plate 210, the end plate 2 or other structural parts will not interfere with the fastener 240, which helps to make the structure of the battery pack more compact and the energy density higher.

[0074] like Figure 5 Each liquid cooling plate 210 includes a main body 213 and two current collectors 214 respectively installed at both ends of the main body 213 along the second direction. The main body 213 is connected to the liquid inlet connector 220 or the liquid outlet connector 230 through the current collectors 214. Figure 6 The fastener 240 passes through the current collector 214 and is connected to the corresponding end plate 2 .

[0075] Exemplarily, a plurality of flow channels extending along the second direction are disposed inside the main body 213 , and the plurality of flow channels may be arranged along the width direction of the liquid cooling plate 210 .

[0076] Exemplarily, the current collector 214 is provided with an inner cavity communicating with all flow channels in the main body 213 , and the liquid inlet connector 220 or the liquid outlet connector 230 connected to the current collector 214 is communicated with the inner cavity.

[0077] For example, the current collector 214 and the main body 213 can be connected by bonding, welding, sleeve connection or integral molding.

[0078] In this embodiment, the current collector 214 and the main body 213 are split and installable structures, so that when the liquid cooling plate 210 is maintained, the main body 213 or the current collector 214 of the liquid cooling plate 210 can be replaced separately, which helps to reduce maintenance costs. At the same time, the fastener 240 passes through the current collector 214 to achieve the connection between the liquid cooling plate 210 and the end plate 2, which can avoid the flow channel space in the main body 213 being squeezed due to the provision of the fastener 240, so that the liquid cooling plate 210 has a larger heat exchange surface, which helps to ensure that the liquid cooling plate 210 has a stronger heat exchange capacity.

[0079] like Figure 7 , Figure 7 The schematic diagram of the side view of the battery pack after the box 300 is removed is shown. Along the second direction, the main body 213 of the liquid cooling plate 210 corresponds to the positions of the multiple battery cells 1 of the battery cell group 10, and the two current collectors 214 of the liquid cooling plate 210 correspond to the positions of the two end plates 2 of the battery cell group 10. Figure 8 , Figure 8 Shown Figure 7 Schematic diagram of the section BB in FIG. Figure 8 The X direction in the figure), each end plate 2 is provided with a current collector 214 on both sides. Each current collector 214 is provided along the width direction of the liquid cooling plate 210 (such as Figure 8 Two fasteners 240 are arranged at intervals (in the Z direction) to further improve the connection reliability between the current collector 214 and the end plate 2.

[0080] like Fig. 9 , Fig. 9 Shown Figure 8 An enlarged schematic diagram of part D in the middle. In some embodiments, a sink 2141 is provided on one side surface of the current collector 214 away from the corresponding end plate 2, and a connecting through hole 2142 for penetrating a fastener 240 is provided in the middle of the sink 2141; the fastener 240 includes a connecting portion 241 penetrating the connecting through hole 2142, and an abutting portion 242 connected to the connecting portion 241; the radial cross-sectional diameter of the abutting portion 242 is greater than the radial cross-sectional diameter of the connecting portion 241, and the abutting portion 242 is located in the sink 2141 and abuts against the bottom of the sink 2141.

[0081] Taking the fastener 240 as a bolt as an example, the connecting portion 241 of the fastener 240 is the threaded rod of the bolt, and the abutting portion 242 is the nut of the bolt. Using a tool to clamp the nut can drive the threaded rod to rotate so that the threaded rod is partially screwed into the end plate 2.

[0082] exist Fig. 9 In the figure, the current collector 214 is connected to the end plate 2 on the right side through the fastener 240 , so the end plate 2 on the right side of the current collector 214 is the end plate 2 corresponding to the current collector 214 .

[0083] The connecting portion 241 of the fastener 240 passes through the sink 2141 and the connecting through hole 2142 in sequence from the left side of the current collector 214, and is connected to the corresponding end plate 2. When the fastener 240 penetrates into the end plate 2 and reaches the predetermined position, the abutting portion 242 located at the end of the connecting portion 241 enters the sink 2141 and abuts against the bottom of the sink 2141 (the bottom of the sink 2141 is provided with a connecting through hole 2142). At this time, the abutting portion 242 is entirely located inside the sink 2141 to prevent the fastener 240 from extending out of the current collector 214. At the same time, the abutting portion 242 abuts against the bottom of the sink 2141, which can generate a thrust acting on the current collector 214 and toward the end plate 2 corresponding to the current collector 214, ensuring that the current collector 214 can be reliably connected to the end plate 2.

[0084] like Fig.10 , Fig.10 Shown Figure 7 Schematic diagram of the cutaway of the CC section. Fig.11 , Fig.11 Shown Fig.10 The enlarged schematic diagram of part E in the figure. Fig.11 In some embodiments, a connection layer 250 is provided between the main body 213 and the battery cell group 10, and the multiple battery cells 1 of the battery cell group 10 are connected to the main body 213 through the connection layer 250. Specifically, Figure 7 The length of the portion of the main body 213 between the two current collectors 214 is not less than the total length of all the battery cells 1 arranged in a single row in the battery cell group 10 , so that the main body 213 can cool each battery cell 1 in the battery cell group 10 .

[0085] like Fig. 9 The side wall of the end plate 2 near the current collector 214 is provided with a limiting structure 201, and the current collector 214 abuts against the limiting structure 201 to define a spacing space between the battery cell 1 and the main body 213. The spacing space is filled with a connecting layer 250, and the spacing space is used to limit the thickness of the connecting layer 250, such as Fig.11 .

[0086] Exemplarily, the limiting structure 201 may be a protrusion protruding from the side surface of the end plate 2 ; or, the limiting structure 201 may be a groove formed on the side surface of the end plate 2 .

[0087] When the current collector 214 is in contact with the limiting structure 201 of the end plate 2, the relative position between the liquid cooling plate 210 and the battery cell group 10 is fixed along the first direction, that is, the spacing distance between the plate surface of the main body 213 and the side wall of the battery cell 1 is also fixed. Since the connecting layer 250 is located between the main body 213 and the battery cell 1, the thickness of the connecting layer 250 will not be greater than the spacing distance between the plate surface of the main body 213 and the side wall of the battery cell 1, that is, the spacing space between the battery cell 1 and the main body 213 is used to limit the thickness of the connecting layer 250.

[0088] like Fig.11 In some embodiments, the current collector 214 is mounted on the end of the body 213 .

[0089] Combination Fig.11 The inner cavity of the current collector 214 is connected to the side of the current collector 214 close to the main body 213 to form an opening, and the main body 213 is inserted into the inner cavity through the opening. The flow channel inside the main body 213 runs through the end of the main body 213 to achieve communication between the flow channel and the inner cavity. The current collector 214 and the main body 213 are connected by a sleeve connection, which can further improve the sealing between the current collector 214 and the main body 213, and help prevent leakage of the coolant during the flow process.

[0090] like Fig.11 In some embodiments, the thickness of the main body 213 is less than the thickness of the current collector 214. The current collector 214 of the embodiment of the present application is mounted on the main body 213, so the thickness of the current collector 214 needs to be greater than the thickness of the main body 213. Fig. 9 A groove is provided on the side wall of the end plate 2 close to the current collector 214 , and the groove is constructed as a limiting structure 201 .

[0091] Generally, the thickness of the connection layer 250 is relatively thin, so in order to reduce the distance between the plate surface of the main body 213 and the side wall of the battery cell 1, a groove is provided on the side wall of the end plate 2. During assembly, the current collector 214 partially enters the groove and abuts against the bottom of the groove, so that the plate surface of the main body 213 is closer to the side wall of the battery cell 1, and the spacing between the main body 213 and the battery cell 1 can meet the thickness requirement of the connection layer 250.

[0092] like Fig.10 In some embodiments, a pipeline connection portion 215 is provided on the side of the current collector 214 away from the main body 213 , and the pipeline connection portion 215 extends out of the end plate 2 along the second direction, and the liquid inlet connector 220 or the liquid outlet connector 230 is connected to the pipeline connection portion 215 .

[0093] Along the second direction, one side of the current collector 214 is connected to the main body 213, and the other side is provided with a pipeline connection portion 215. The current collector 214 is connected to the liquid inlet joint 220 or the liquid outlet joint 230 through the pipeline connection portion 215 extending out of the end plate 2, which can effectively prevent the liquid inlet joint 220 or the liquid outlet joint 230 from interfering with the end plate 2.

[0094] like Figure 7 In some embodiments, each current collector 214 is provided with a pipe connection portion 215. In the same liquid cooling plate 210, along the third direction (eg Figure 7 The two pipe connection parts 215 are respectively close to the opposite sides of the liquid cooling plate 210; the third direction is perpendicular to the first direction and the second direction.

[0095] Exemplarily, the third direction is parallel to the width direction of the liquid cooling plate 210 .

[0096] by Figure 7 Taking the structure and direction shown in as an example for further explanation, the pipe connection part 215 of the left current collector 214 is arranged at the upper part of the liquid cooling plate 210, and the pipe connection part 215 of the right current collector 214 is arranged at the lower part of the liquid cooling plate 210. Exemplarily, the coolant can enter the main body 213 from the pipe connection part 215 on the upper left side of the main body 213, and flow into each flow channel in the main body 213 respectively. After the coolant flows from the left end to the right end of the main body 213, it converges at the lower right side of the main body 213 and flows out through the pipe connection part 215. The two pipe connections 215 of the same liquid cooling plate 210 are respectively located at the upper and lower parts of the liquid cooling plate 210, which helps to make the coolant flow in each flow channel arranged vertically in the main body 213 more uniform, further improving the temperature consistency of the battery pack.

[0097] It should be noted that the above describes some embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0098] The various embodiments in the present application are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0099] The description of the present application is given for the purpose of illustration and description, and is not intended to be exhaustive or to limit the present application to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present application, and to enable those of ordinary skill in the art to understand the present application and thus design various embodiments with various modifications suitable for specific purposes.

[0100] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0101] Although the present application has been described in conjunction with specific embodiments thereof, many alternatives, modifications and variations of these embodiments will be apparent to those skilled in the art in light of the foregoing description.

[0102] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A battery pack, characterized in that: include: Battery cell stack; A liquid cooling component, the liquid cooling component includes a liquid cooling plate, a liquid inlet joint and a liquid outlet joint, the liquid cooling plate is in contact with the battery cell stack for heat exchange, the liquid inlet joint and the liquid outlet joint are respectively connected to the liquid cooling plate, wherein the number of one of the liquid inlet joint and the liquid outlet joint is odd, and the number of the other is even.

2. The battery pack according to claim 1, characterized in that: The number of the liquid inlet connector is one, and the number of the liquid outlet connector is two.

3. The battery pack according to claim 2, characterized in that: The battery cell stack includes at least two battery cell groups arranged along a first direction, each of the battery cell groups includes a plurality of battery cells arranged along a second direction; the first direction intersects with the second direction; The liquid cooling plates are provided in plurality, and the plurality of liquid cooling plates include a liquid inlet cold plate connected to the liquid inlet joint, and a liquid outlet cold plate connected to the liquid outlet joint; the liquid inlet cold plate is located between adjacent battery cell groups, the liquid outlet cold plates are located on both sides of the battery cell stack along the first direction, and the liquid outlet cold plates are connected to the liquid inlet cold plates.

4. The battery pack according to claim 3, characterized in that: Two liquid inlet cold plates are provided and are arranged at intervals along the first direction, and one liquid outlet cold plate is provided on two relatively outer sides of the two liquid inlet cold plates respectively; one liquid inlet joint is connected to the two liquid inlet cold plates respectively, and two liquid outlet joints are connected to the two liquid outlet cold plates one by one.

5. The battery pack according to claim 3, characterized in that: Each of the battery cell groups comprises two end plates spaced apart along the second direction, and the plurality of battery cells are located between the two end plates; The liquid cooling plate is connected to the corresponding end plate through a fastener; the portion of the fastener located outside the end plate is arranged inside the liquid cooling plate.

6. The battery pack according to claim 5, characterized in that: Each of the liquid cooling plates includes a main body and two current collectors respectively installed at both ends of the main body along the second direction. The main body is connected to the liquid inlet connector or the liquid outlet connector through the current collectors, and the fasteners pass through the current collectors and are connected to the corresponding end plates.

7. The battery pack according to claim 6, characterized in that: A sinker is provided on the surface of one side of the current collector away from the corresponding end plate, and a connecting through hole is provided in the middle of the sinker; the fastener includes a connecting portion passing through the connecting through hole, and an abutting portion connected to the connecting portion; the radial cross-sectional diameter of the abutting portion is larger than the radial cross-sectional diameter of the connecting portion, and the abutting portion is located in the sinker and abuts against the bottom of the sinker.

8. The battery pack according to claim 6, characterized in that: A connection layer is provided between the main body and the battery cell group, and the plurality of battery cells in the battery cell group are connected to the main body through the connection layer; A limiting structure is provided on the side wall of the end plate close to the current collector, and the current collector abuts against the limiting structure to define a spacing space between the battery cell and the main body; The spacing space is used to define the thickness of the connecting layer.

9. The battery pack according to claim 8, characterized in that: The thickness of the main body is smaller than the thickness of the current collector, and a groove is provided on the side wall of the end plate close to the current collector, and the groove is configured as the limiting structure.

10. The battery pack according to claim 6, characterized in that: A pipeline connection portion is provided on a side of the current collector away from the main body, the pipeline connection portion extends out of the end plate along the second direction, and the liquid inlet connector or the liquid outlet connector is connected to the pipeline connection portion.

11. The battery pack according to claim 10, characterized in that: Each of the current collectors is provided with a pipeline connection portion. In the same liquid cooling plate, along the third direction, the two pipeline connection portions are respectively close to opposite sides of the liquid cooling plate; the third direction is respectively perpendicular to the first direction and the second direction.

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