Battery pack

Abstract

The application relates to the technical field of batteries, and discloses a battery pack, which comprises battery cells, the battery cells comprise a plurality of single batteries, and the stacking direction of the plurality of single batteries is perpendicular to the large surface of the single batteries; and a separation unit is arranged between two adjacent single batteries, the opposite sides of the separation unit comprise a heat exchange surface and a heat insulation surface, the heat exchange surface and the heat insulation surface are respectively in contact with the large surfaces of the two adjacent single batteries, so that the separation unit is in heat exchange contact with the large surface of one single battery and in heat insulation contact with the large surface of the other single battery; on the basis of realizing reliable heat exchange of one single battery, heat transfer between the two adjacent single batteries can be avoided, so that when one single battery is in thermal runaway, the other single battery can also be prevented from being in thermal runaway, and the safety performance of the battery pack can be improved.

Description

[0001] This case is a divisional application of application number 202211328352.0, filed on October 27, 2022, with the invention title "Battery Pack". Technical Field

[0002] This invention relates to the field of battery technology, and more particularly to a battery pack. Background Technology

[0003] In related technologies, a battery pack may include multiple batteries. During the charging and discharging process of the battery pack, a large amount of heat may be generated, which requires timely cooling of the battery pack. However, in some cases, this can easily lead to battery safety issues. Summary of the Invention

[0004] This invention provides a battery pack to improve the performance of the battery pack.

[0005] This invention provides a battery pack, comprising: A battery cell comprises multiple individual cells, the stacking direction of which is perpendicular to the large surface of the individual cells. A separating unit is disposed between two adjacent individual cells. The opposite sides of the separating unit include a heat exchange surface and a heat insulation surface. The heat exchange surface and the heat insulation surface are in contact with the large surface of the two adjacent individual cells, so that the separating unit has heat exchange contact with the large surface of one individual cell and heat insulation contact with the large surface of the other individual cell.

[0006] The battery pack of this invention includes battery cells and separator units. Each battery cell comprises multiple individual cells, and the stacking direction of these individual cells is perpendicular to their large surfaces, thereby improving the stacking capability of the individual cells. The separator unit is positioned between two adjacent individual cells. By including heat exchange and heat insulation surfaces on opposite sides of the separator unit, and having these surfaces in contact with the large surfaces of the two adjacent individual cells, the separator unit achieves heat exchange contact with the large surface of one individual cell and heat insulation contact with the large surface of the other. This ensures reliable heat exchange for each individual cell while preventing excessive heat transfer between adjacent cells through heat exchange contact. Since the large surface area of ​​the battery cell has the largest heat exchange area and the fastest heat exchange rate, it prevents thermal runaway in one individual cell from causing thermal runaway in another, thus improving the safety performance of the battery pack. Attached Figure Description

[0007] To better understand this disclosure, reference may be made to the embodiments shown in the following figures. Components in the figures are not necessarily to scale, and related elements may be omitted to emphasize and clearly illustrate the technical features of this disclosure. Additionally, related elements or components may have different arrangements as known in the art. Furthermore, in the figures, the same reference numerals denote the same or similar components in various figures. Wherein: Figure 1 This is a partial structural schematic diagram of a battery pack according to an exemplary embodiment; Figure 2 This is a schematic diagram of a battery pack according to another exemplary embodiment; Figure 3 This is a partial structural schematic diagram of a battery pack according to an exemplary embodiment; Figure 4 This is a partial structural schematic diagram of a battery pack according to another exemplary embodiment; Figure 5 This is a structural schematic diagram of a battery pack partition unit shown from a first view according to a first exemplary embodiment; Figure 6 This is a structural schematic diagram from a second perspective of a battery pack partition unit shown according to a first exemplary embodiment; Figure 7 This is a structural schematic diagram of a battery pack partition unit from a third perspective, according to a first exemplary embodiment. Figure 8 This is a schematic diagram of the structure of a single cell in a battery pack according to an exemplary embodiment; Figure 9 This is a schematic diagram illustrating the mating structure of a battery pack's partition unit and a metal component according to an exemplary embodiment; Figure 10 This is a schematic diagram of the structure of a battery pack partition unit according to a second exemplary embodiment; Figure 11 This is a schematic diagram of the structure of a battery pack partition unit according to a third exemplary embodiment.

[0008] The annotations in the attached figures are explained as follows: 10. Battery cell; 11. Single cell; 111. Large surface area; 20. Separating unit; 21. Heat exchange surface; 22. Heat insulation surface; 23. Heat conducting element; 231. Channel; 24. Heat insulation element; 25. First channel layer; 26. Second channel layer; 27. Buffer section; 30. Battery housing; 40. Heat exchange pipeline; 50. Metal parts; 51. Cavity. Detailed Implementation

[0009] The technical solutions in the exemplary embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. The exemplary embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of this disclosure.

[0010] In the description of this disclosure, unless otherwise expressly specified and limited, the terms “first” and “second” are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term “multiple” refers to two or more; and the term “and / or” includes any and all combinations of one or more associated listed items. In particular, references to “the / described” object or “a” object are also intended to indicate one of a possible plurality of such objects.

[0011] Unless otherwise specified or stated, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0012] Furthermore, it should be understood that the directional terms such as "upper," "lower," "inner," and "outer" described in the exemplary embodiments of this disclosure are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the exemplary embodiments of this disclosure. It should also be understood that, in the context of a reference to an element or feature being connected to another element (one or more) "upper," "lower," "inner," or "outer," it can be directly connected to the other element (one or more) "upper," "lower," "inner," or "outer," or indirectly connected to the other element (one or more) "upper," "lower," "inner," or "outer" through an intermediate element.

[0013] One embodiment of the present invention provides a battery pack, please refer to... Figures 1 to 8 The battery pack includes: a battery cell 10, which includes multiple individual cells 11, the stacking direction of which is perpendicular to the large surface 111 of the individual cells 11; and a separator 20, which is disposed between two adjacent individual cells 11. The separator 20 has a heat exchange surface 21 and a heat insulation surface 22 on opposite sides, and the heat exchange surface 21 and the heat insulation surface 22 are in contact with the large surface 111 of the two adjacent individual cells 11, so that the separator 20 has heat exchange contact with the large surface 111 of one individual cell 11 and heat insulation contact with the large surface 111 of the other individual cell 11.

[0014] A battery pack according to one embodiment of the present invention includes a battery cell 10 and a separator 20. The battery cell 10 includes a plurality of individual cells 11. The stacking direction of the plurality of individual cells 11 is perpendicular to the large surface 111 of the individual cells 11, thereby improving the stacking capability of the individual cells 11. The separator 20 is disposed between two adjacent single cells 11. By having heat exchange surface 21 and heat insulation surface 22 on opposite sides of the separator 20, and the heat exchange surface 21 and heat insulation surface 22 respectively in contact with the large surface 111 of the two adjacent single cells 11, the separator 20 can have heat exchange contact with the large surface 111 of one single cell 11 and heat insulation contact with the large surface 111 of the other single cell 11. This improves the heat exchange rate of the battery pack, enabling rapid heating or cooling of the battery pack, improving the overall safety performance of the battery pack and ensuring good overall consistency of the battery pack, thus extending the battery life. It also avoids a large amount of heat transfer between two adjacent single cells 11, thereby preventing the other single cell 11 from experiencing thermal runaway if one single cell 11 does, thus improving the safety performance of the battery pack.

[0015] It should be noted that the large surface 111 of the single cell 11 can be considered the surface that generates the most heat in the battery. Furthermore, the large surface 111 of the single cell 11 can be the surface with the largest area of ​​the single cell 11, for example, combined with... Figure 8 As shown, when the single cell 11 is a square cell, the surface with the largest area of ​​the square cell can be the large surface 111 of the single cell 11. There can be two large surfaces 111 of the single cell 11. By making the heat exchange surface 21 of the separating unit 20 contact the large surface 111 of one single cell 11, the separating unit 20 can achieve rapid cooling of the single cell 11, thereby avoiding thermal runaway of the single cell 11. The heat insulation surface 22 of the separating unit 20 contacts the large surface 111 of the other single cell 11, thereby preventing the heat of one single cell 11 from being transferred to another single cell 11, thereby preventing a large amount of heat transfer between the single cells 11, and thus preventing the problem of thermal runaway caused by the large accumulation of heat on a single cell 11, thereby improving the safety performance of the battery.

[0016] The large surface 111 of the single cell 11 is in contact with the heat exchange surface 21 of the separator unit 20, thereby significantly improving the heat exchange rate of the single cell 11. In related technologies, when a single cell 11 experiences thermal runaway, the cooling rate of the heat exchange structure to the single cell is less than the heat transfer rate of the heat exchange structure, thus making it easier for adjacent single cells to experience thermal runaway. However, in this embodiment, by making the heat insulation surface 22 of the separator unit 20 contact another single cell 11, the heat of the single cell 11 experiencing thermal runaway can be prevented from being transferred to the other single cell 11, thereby effectively preventing a chain reaction of thermal runaway.

[0017] The heat exchange surface 21 is in contact with the large surface 111 of the single cell 11, that is, the heat exchange surface 21 and the large surface 111 of the single cell 11 can be in direct contact, or the heat exchange surface 21 and the large surface 111 of the single cell 11 can be indirect contact. The heat exchange surface 21 and the large surface 111 of the single cell 11 can be indirectly contacted through other structures, such as heat exchange surface 21 and the large surface 111 of the single cell 11 can be contacted through structures such as insulating parts, adhesives or buffers.

[0018] Correspondingly, the heat insulation surface 22 is in contact with the large surface 111 of the single cell 11, that is, the heat insulation surface 22 and the large surface 111 of the single cell 11 can be in direct contact, or the heat insulation surface 22 and the large surface 111 of the single cell 11 can be indirect contact. The heat insulation surface 22 and the large surface 111 of the single cell 11 can form indirect contact through other structures, such as heat insulation surface 22 and the large surface 111 of the single cell 11 can be in contact through structures such as insulating parts, adhesives or buffers.

[0019] In one embodiment, such as Figures 5 to 7 As shown, the separating unit 20 includes: a heat-conducting element 23 having a heat exchange surface 21; and a heat-insulating element 24 having a heat-insulating surface 22. This allows the separating unit 20 to reliably exchange heat with the corresponding single cell 11 through the heat-conducting element 23, and the separating unit 20 to insulate the heat between two adjacent single cells 11 through the heat-insulating element 24, thereby improving the safe use performance of the battery.

[0020] In one embodiment, the heat-conducting element 23 is connected to the heat-insulating element 24 to improve the stability of the separator unit 20 and avoid instability between the heat-conducting element 23 and the heat-insulating element 24, which could lead to connection failure of either the heat-conducting element 23 or the heat-insulating element 24, thereby ensuring the safety performance of the battery pack.

[0021] It should be noted that the heat-conducting element 23 and the heat-insulating element 24 can be directly connected, for example, by bonding; or, the heat-conducting element 23 and the heat-insulating element 24 can be indirectly connected, for example, by providing other structures between them, such as a buffer structure, and both the heat-conducting element 23 and the heat-insulating element 24 are bonded to the buffer structure. Alternatively, the heat-conducting element 23 and the heat-insulating element 24 can be reliably connected by the compressive force between two adjacent single cells 11, for example, at least one of the heat-conducting element 23 and the heat-insulating element 24 can be an elastic element, thereby ensuring that the heat-conducting element 23 and the heat-insulating element 24 are reliably connected by the compressive force.

[0022] In one embodiment, the heat-conducting element 23 can be a metal plate, such as... Figure 3 and Figure 5 As shown, a channel 231 can be formed inside the metal plate. The channel 231 can be a heat exchange channel. Gas or liquid can flow inside the channel 231, or a phase change material can be placed inside the channel 231.

[0023] Combination Figure 1 As shown, the battery pack can introduce gas or liquid into the channel 231 through the heat exchange pipe 40 to achieve gas or liquid circulation. The specific structure of the heat exchange pipe 40 and the channel 231 is not limited here.

[0024] The thermally conductive element 23 can also be a thermally conductive pad, for example, a graphene sheet, a thermally conductive silicone sheet, or a thermally conductive insulating elastic rubber sheet, etc.

[0025] The heat insulation element 24 can be an aerogel pad, foam, fiberglass, asbestos, ceramic paper, etc. Alternatively, the heat insulation element 24 can be a heat insulation coating. For example, a heat insulation coating can be directly coated on the surface of the heat-conducting element 23, or a ceramic coating can be coated on the surface of the heat-conducting element 23. Alternatively, the heat insulation element 24 can also include a metal part, and a heat insulation coating can be coated on the surface of the metal part.

[0026] In one embodiment, the heat-conducting element 23 is a heating film. For example, the heating film can be a graphene heating film, a PET heating film, or a PI heating film, etc. It not only has a simple structure, but also ensures good heating performance. The heating film can be used to quickly heat up the individual cells 11 in the early stage of the battery pack, or it can be used to heat the individual cells 11 when the ambient temperature is low.

[0027] In one embodiment, the heat-conducting element 23 may include a metal plate and a heating film to improve the heat exchange capacity of the battery pack. For example, the metal plate is provided with a channel 231, which can be a cooling channel. After the battery has been used for a long time, it can be cooled by the metal plate. The heating film can be heated according to the usage requirements of the battery pack to meet the usage requirements of the battery pack.

[0028] In one embodiment, the battery pack further includes a metal element 50 disposed on the side of the heat insulation element 24 away from the heat conduction element 23, so that the heat insulation surface 22 contacts the large surface 111 of the single cell 11 through the metal element 50, thereby increasing the isolation distance between the heat insulation element 24 and the single cell 11, and thus improving the safety performance of the battery pack.

[0029] Metal part 50 can be used for heat exchange, combined with Figure 9 As shown, the heat-conducting element 23 is a metal plate, and a channel 231 is formed inside the metal plate. A cavity 51 is formed inside the metal part 50. The channel 231 can be a heat exchange channel, and the cavity 51 can also be a heat exchange channel. Gas, liquid or phase change material can be placed inside the heat exchange channel.

[0030] There can be multiple channels 231 and multiple cavities 51. Alternatively, there can be one channel 231 and one cavity 51.

[0031] The metal part 50 can also be used for heat insulation. For example, the metal part 50 can be coated with a heat insulation coating, or the cavity 51 inside the metal part 50 can be filled with a heat insulation medium, such as aerogel, foam or fiberglass, etc., or the cavity 51 can be filled with a liquid heat insulation medium or a gaseous heat insulation medium, etc., which is not limited here.

[0032] In one embodiment, the heat insulation element 24 is a heat insulation coating or a heat insulation pad, which can effectively block heat while also ensuring that the heat insulation element 24 has a relatively simple structural form.

[0033] When the heat insulation element 24 is a heat insulation coating, the heat insulation coating can be directly applied to the heat conduction element 23. Of course, in some embodiments, it is not excluded that the heat insulation coating can be directly applied to the single cell 11, and the surface of the heat insulation coating in contact with the single cell 11 is the heat insulation surface 22, so that the heat insulation coating can effectively block the heat of the single cell 11.

[0034] When the heat insulation element 24 is a heat insulation pad, the heat insulation pad can be connected to the heat conduction element 23. For example, the heat insulation pad can be bonded to the heat conduction element 23. The surface of the heat insulation pad that contacts the single cell 11 is the heat insulation surface 22, so that the heat insulation pad can effectively block the heat of the single cell 11.

[0035] In one embodiment, the heat insulation element 24 is a heat insulation coating, which is disposed on the outer surface of the heat-conducting element 23 so as to contact the large surface 111 of the single cell 11, thereby forming a reliable heat insulation effect.

[0036] In one embodiment, the heat insulation element 24 is a heat insulation pad, which is bonded to the heat conduction element 23. This ensures the connection stability between the heat conduction element 23 and the heat insulation element 24 while guaranteeing effective heat insulation of the heat insulation element 24.

[0037] In one embodiment, the heat insulation element 24 includes a heat insulation pad and a heat insulation coating, the heat insulation coating being disposed on the outer surface of the heat insulation pad and / or the outer surface of the heat-conducting element 23. The combined arrangement of the heat insulation pad and the heat insulation coating can further increase the heat insulation capacity, thereby improving the battery's safety performance and preventing the problem of failure to block heat when one of them is damaged.

[0038] The heat insulation coating may be applied to the side of the heat insulation pad facing the large surface 111 of the single cell 11, or the heat insulation coating may be applied to the side of the heat insulation pad facing the heat conduction element 23, or both opposite sides of the heat insulation pad may have a heat insulation coating.

[0039] In one embodiment, the thermal conductivity of the heat insulation element 24 is ≤0.05 W / (m·k), which enables the heat insulation element 24 to have a reliable heat insulation effect. Even if a single cell 11 experiences thermal runaway, it can effectively block the heat transfer to another adjacent single cell 11, thereby avoiding a chain reaction of thermal runaway problems and improving the safety performance of the battery pack.

[0040] The thermal conductivity of the insulation element 24 can be 0.05 W / (m·k), 0.04 W / (m·k), 0.035 W / (m·k), 0.03 W / (m·k), 0.029 W / (m·k), 0.028 W / (m·k), 0.025 W / (m·k), 0.024 W / (m·k), 0.023 W / (m·k), 0.022 W / (m·k), 0.021 W / (m·k), 0.02 W / (m·k), 0.01 W / (m·k), or 0.004 W / (m·k), etc.

[0041] In one embodiment, the thickness of the heat-conducting element 23 is 3mm-8mm. While ensuring that the heat-conducting element 23 has reliable heat exchange capability, it can avoid the space utilization rate of the battery pack being affected by the excessive thickness of the heat-conducting element 23, thereby ensuring that the battery pack has reliable energy density.

[0042] The thickness of the heat-conducting element 23 can be 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 7.6mm, 7.7mm, 7.8mm, 7.9mm, or 8mm, etc.

[0043] In one embodiment, the thickness of the heat insulation element 24 is less than 5 mm, which can avoid the heat insulation element 24 being too thick and occupying a large assembly space, thereby improving the space utilization of the battery pack and thus improving the energy density of the battery.

[0044] In one embodiment, the thickness of the heat insulation element 24 is ≤3mm, thereby further reducing the thickness of the heat insulation element 24 and improving the space utilization of the battery pack.

[0045] In one embodiment, the thickness of the separator unit 20 is 4mm-13mm. While ensuring that the separator unit 20 has reliable heat exchange and insulation capabilities, it avoids the separator unit 20 occupying too much space, thereby improving the space utilization rate of the battery pack.

[0046] The thickness of the partition unit 20 can be 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 7.6mm, 7.7mm, 7.8mm, 7.9mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 12.6mm, 12.7mm, 12.8mm, 12.9mm, or 13mm, etc.

[0047] In one embodiment, at least one of the thermally conductive element 23 and the thermally insulating element 24 includes a buffer portion to absorb the expansion of the large surface 111 of the single cell 11, thereby ensuring the performance of the single cell 11.

[0048] After prolonged use, the individual battery 11 may experience expansion, especially on its large surface 111. In this case, by including at least one of the heat-conducting element 23 and the heat-insulating element 24 as a buffer portion, the individual battery 11 can compress the buffer portion during the expansion process. This allows the buffer portion to absorb the expansion of the large surface 111 of the individual battery 11, thus ensuring that the individual battery 11 can still exert its energy normally in the later stages and avoiding safety risks caused by the inability to release the expansion force.

[0049] When the heat-conducting element 23 is a metal plate, the channels of the metal plate can be used as a buffer, that is, the channels 231 can be compressed, thereby absorbing the expansion of the large surface 111 of the single cell 11. When the heat-insulating element 24 is a heat-insulating pad, it can also absorb the expansion of the large surface 111 of the single cell 11 by utilizing its own elasticity.

[0050] In one embodiment, along the mounting direction perpendicular to the stacking direction, the distance between the opposite ends of the heat insulation element 24 is greater than the distance between the opposite ends of the heat conduction element 23. While ensuring that the heat insulation element 24 reliably blocks heat, the relatively large heat insulation element 24 can also be used as a positioning structure. This not only facilitates the installation of the separator unit 20 between the individual batteries 11, but also allows it to be used as a positioning structure during subsequent installation, thus avoiding damage to the heat conduction element 23.

[0051] In one embodiment, such as Figure 1 As shown, the battery pack also includes a battery housing 30, and the battery unit 10 is disposed inside the battery housing 30. The installation direction is perpendicular to the bottom surface of the battery housing 30, so that the heat insulation element 24 is connected to the bottom surface and the heat conduction element 23 is spaced apart from the bottom surface. This allows the heat insulation element 24 to be positioned and connected to the battery housing 30 as a positioning structure, while the heat conduction element 23 can be suspended to avoid damage to the heat conduction element 23 by the battery housing 30.

[0052] Along the installation direction, the side of the heat insulation element 24 facing the bottom surface of the battery box 30 can be flush with the side of the individual battery 11 facing the bottom surface of the battery box 30; or, the side of the heat insulation element 24 facing the bottom surface of the battery box 30 can be higher than the side of the individual battery 11 facing the bottom surface of the battery box 30, and other connecting structures, such as an adhesive layer, can be provided between the individual battery 11 and the bottom surface of the battery box 30; or, the side of the heat insulation element 24 facing the bottom surface of the battery box 30 can be lower than the side of the individual battery 11 facing the bottom surface of the battery box 30, and other connecting structures, such as an adhesive layer, can be provided between the heat insulation element 24 and the bottom surface of the battery box 30.

[0053] The side of the heat insulation element 24 facing the bottom of the battery box 30 is higher than the side of the heat conduction element 23 facing the bottom of the battery box 30, while the other side of the heat insulation element 24 away from the bottom of the battery box 30 can be flush with the other side of the heat conduction element 23 away from the bottom of the battery box 30.

[0054] Combination Figure 1 As shown, the stacking direction of the multiple individual cells 11 of the battery unit 10 is represented by A, and the mounting direction perpendicular to the stacking direction can be represented by B. In this case, the mounting direction B can be a direction perpendicular to the bottom surface of the battery box 30.

[0055] It should be noted that multiple individual batteries 11 are arranged along the stacking direction, while the mounting direction is perpendicular to the stacking direction. The mounting direction can be perpendicular to the bottom surface of the battery box 30; or, the mounting direction can be perpendicular to the side surface of the battery box 30. In this case, along the mounting direction perpendicular to the stacking direction, the distance between the opposite ends of the heat insulation element 24 is greater than the distance between the opposite ends of the heat conduction element 23, and the heat insulation element 24 can also be used to connect to the side surface of the battery box 30.

[0056] In some embodiments, it is not excluded that the distance between the opposite ends of the heat insulation element 24 can be equal to the distance between the opposite ends of the heat conduction element 23 along the mounting direction perpendicular to the stacking direction, and the heat insulation element 24 and the heat conduction element 23 can be staggered, so that the heat insulation element 24 can be connected to the battery box 30, while the heat conduction element 23 can be spaced apart from the battery box 30.

[0057] Alternatively, along the installation direction perpendicular to the stacking direction, the distance between the opposite ends of the heat insulation element 24 can be less than the distance between the opposite ends of the heat conduction element 23, and the heat insulation element 24 and the heat conduction element 23 can be staggered, so that the heat insulation element 24 can be connected to the battery box 30, while the heat conduction element 23 can be spaced apart from the battery box 30.

[0058] Alternatively, the distance between the two ends of the heat-conducting element 23 facing the side wall of the battery box 30 can be greater than the distance between the two ends of the heat insulation element 24 facing the side wall of the battery box 30, so as to facilitate the connection between the heat-conducting element 23 and the heat exchange pipeline 40.

[0059] It should be noted that the specific structure of the battery housing 30 is not limited here. The battery housing 30 is used to install the individual battery cells 11 and can form a sealed space for supplying power to vehicles, etc. Alternatively, the battery housing 30 can be connected to the external environment for storage, etc.

[0060] In one embodiment, at least one of the heat exchange surface 21 and the heat insulation surface 22 is bonded and fixed to the large surface 111 of the single cell 11, thereby ensuring that the separator unit 20 can be stably disposed between two adjacent single cells 11, thus ensuring the safe use performance of the battery.

[0061] The heat exchange surface 21 can be connected to the single cell 11 through thermally conductive structural adhesive, and the heat insulation surface 22 can be connected to the single cell 11 through aerogel.

[0062] In one embodiment, such as Figure 10As shown, the separating unit 20 includes a metal structure, and at least a first channel layer 25 and a second channel layer 26 are formed inside the metal structure. The first channel layer 25 and the second channel layer 26 are heat exchange channels and heat insulation channels, respectively, to form heat exchange surfaces 21 and heat insulation surfaces 22. That is, heat exchange elements and heat insulation elements can be formed through the channels inside the metal structure, which can not only meet the needs of heat exchange and heat insulation, but also has strong structural stability, thereby increasing the safety performance and service life of the battery pack.

[0063] The metal structure can be a one-piece structure, and a first channel layer 25 and a second channel layer 26 can be formed on both sides of the metal structure, respectively. For example, the first channel layer 25 and the second channel layer 26 can be formed through multiple separated channels, such as... Figure 10 As shown. Of course, the first channel layer 25 and the second channel layer 26 can also be two large cavities.

[0064] The first channel layer 25 is a heat exchange channel, which can be filled with heat exchange gas, heat exchange liquid or phase change material.

[0065] The second channel layer 26 is a heat insulation channel, which is filled with a heat insulation medium, such as aerogel, foam or fiberglass, etc. Alternatively, the heat insulation channel can also be filled with a liquid heat insulation medium or a gaseous heat insulation medium, etc., which is not limited here.

[0066] In one embodiment, such as Figure 11 As shown, the separating unit 20 includes a metal structure, and at least a first channel layer 25 and a second channel layer 26 are formed inside the metal structure. The first channel layer 25 and the second channel layer 26 are respectively a heat insulation channel and a channel, forming a heat exchange surface 21 and a heat insulation surface 22 respectively. A buffer portion 27 is provided between the first channel layer 25 and the second channel layer 26, so as to absorb the expansion of the large surface 111 of the single cell 11 through the buffer portion 27, and also to prevent the single cell 11 or the metal structure from being pressed, thus ensuring the safe use performance of the single cell 11.

[0067] In one embodiment, no heat-conducting element 23 is provided between the heat insulation surface 22 and the large surface 111 of the single cell 11 on the side away from the heat exchange surface 21. That is, no heat-conducting element 23 is provided between the heat insulation surface 22 and the large surface 111 of the single cell 11, whether they are in direct or indirect contact, thereby reducing the number of components between the single cells 11 and thus increasing the energy density of the battery pack.

[0068] In one embodiment, a heat-conducting element 23 is provided between the heat insulation surface 22 and the large surface 111 of the single cell 11 on the side away from the heat exchange surface 21, that is, the heat insulation surface 22 and the large surface 111 of the single cell 11 can be in indirect contact, thereby increasing the heat exchange capacity of the single cell 11.

[0069] In one embodiment, such as Figure 2 As shown, a separator unit 20 is provided between each two adjacent individual cells 11, so that the two opposite large surfaces 111 of the middle individual cell 11 are in contact with the heat exchange surface 21 and the heat insulation surface 22 respectively. This improves the heat exchange of the individual cells 11 and enhances the heat insulation between the individual cells 11, thereby improving the safe operation of the battery pack.

[0070] When there are three or more individual cells 11, there can be two or more separator units 20. For example, when there are three individual cells 11, the middle individual cell 11 has separator units 20 on both sides, and the opposite sides of the individual cell 11 are in contact with the heat exchange surface 21 and the heat insulation surface 22, respectively. Therefore, it can be understood that the arrangement of multiple separator units 20 is such that the heat exchange surface 21 of each separator unit 20 faces the same direction, and the heat insulation surface 22 of each separator unit 20 faces the same direction. Furthermore, it can be considered that the heat-conducting element 23, the heat insulation element 24, the heat-conducting element 23, the heat insulation element 24... are alternately arranged, or the heat insulation element 24, the heat-conducting element 23, the heat insulation element 24, the heat-conducting element 23... are alternately arranged.

[0071] Combination Figure 3 As shown, a separator unit 20 can be provided between the two individual cells 11, and a heat insulation element 24 and a heat conduction element 23 can be respectively provided on the other large surface 111 of the two individual cells 11.

[0072] Combination Figure 4 As shown, a heat insulation element 24 and a heat conduction element 23 can be respectively provided on the two opposite large surfaces 111 of a single cell 11.

[0073] In one embodiment, at least one end of the battery cell 10 is provided with a heat insulation element 24 along the stacking direction, so as to avoid the problem of excessive heat dissipation of the single battery cell 11 located at the end, thereby ensuring the overall stability and balance of the battery cell 10, so as to achieve the best use state of the battery pack.

[0074] In one embodiment, the single cell 11 is a lithium iron phosphate battery, thereby heat can be retained by the heat insulation element 24 provided at the end, avoiding excessive heat loss of the single cell 11 at the end, thus ensuring the performance of the battery pack.

[0075] The battery can be a lithium iron phosphate battery, with an energy density ranging from 120Wh / kg to 190Wh / kg. Specific energy densities for lithium iron phosphate batteries include 120Wh / kg, 121Wh / kg, 125Wh / kg, 140Wh / kg, 150Wh / kg, 160Wh / kg, 170Wh / kg, 180Wh / kg, 185Wh / kg, 188Wh / kg, and 190Wh / kg, among others.

[0076] In one embodiment, along the stacking direction, thermal conductive elements 23 and thermal insulation elements 24 are respectively provided at opposite ends of the battery cell 10, so that the two opposite large surfaces 111 of each single cell 11 can contact the thermal conductive elements 23 and thermal insulation elements 24 respectively, thereby ensuring reliable heat exchange and further ensuring thermal insulation efficiency, and thus ensuring the safety performance of the battery.

[0077] In one embodiment, no heat-conducting element 23 or heat-insulating element 24 is provided at the opposite ends of the battery cell 10 along the stacking direction, so that the two individual cells 11 at the very end can freely exchange heat, thereby improving the heat exchange capacity of the battery cell 10 and improving the safe use performance of the battery pack.

[0078] In one embodiment, a heat-conducting element 23 is provided between adjacent individual cells 11, so that each heat-conducting element 23 can reliably dissipate heat from each individual cell 11, thereby ensuring the heat exchange capacity of the battery cell 10 and reducing the possibility of thermal runaway in the individual cell 11.

[0079] For example, there can be three or more individual cells 11. For instance, when there are three individual cells 11, a separator 20 can be provided between two individual cells 11. The separator 20 includes a heat-conducting element 23 and a heat-insulating element 24. The other two individual cells 11 can only be provided with a heat-conducting element 23. That is, the partial structural arrangement of the battery pack can be individual cells 11, heat-conducting element 23, heat-insulating element 24, individual cells 11, heat-conducting element 23, and individual cells 11.

[0080] When there are three or more individual cells 11, a separator unit 20 may be provided between each two adjacent individual cells 11, or only a heat-conducting element 23 may be provided between some individual cells 11, which is not limited here.

[0081] In one embodiment, a heat insulation element 24 is provided between adjacent individual cells 11. The number of heat insulation elements 24 is less than the number of heat conducting elements 23, thereby reducing the space occupied by the heat insulation elements 24 in the battery pack, thereby improving the space utilization of the battery pack and thus improving the energy density of the battery pack.

[0082] It should be noted that the heat insulation element 24 does not have to be installed between any two adjacent individual cells 11. After all, the need for heat insulation can be relatively small compared to the need for heat dissipation, and it is sufficient to avoid the chain thermal runaway problem caused by individual cells 11 under normal use of the battery pack.

[0083] In one embodiment, a heat-conducting element 23 is provided between adjacent individual cells 11, and a heat-insulating element 24 is provided between adjacent individual cells 11. The number of heat-insulating elements 24 is less than the number of heat-conducting elements 23, so that the heat-conducting elements 23 can reliably dissipate heat from the individual cells 11, while the heat-insulating elements 24 can block the heat of some individual cells 11, thereby improving the space utilization of the battery pack and ensuring the safe use performance of the battery.

[0084] It should be noted that some individual cells 11 may not have heat-conducting elements 23 and heat-insulating elements 24 between them, or any two adjacent individual cells 11 may have heat-conducting elements 23 and heat-insulating elements 24 between them. However, a heat-conducting element 23 may be provided on an individual cell 11 located at the end, thereby making the number of heat-conducting elements 23 greater than the number of heat-insulating elements 24.

[0085] In some embodiments, it is not excluded that the number of heat insulation elements 24 is greater than the number of heat conduction elements 23. For example, heat conduction elements 23 and heat insulation elements 24 can be provided between any two adjacent single cells 11. However, heat insulation elements 24 can be provided on a single cell 11 located at the end.

[0086] In one embodiment, at least some of the parallel-connected individual cells 11 are not provided with heat insulation element 24. When one of the parallel-connected individual cells 11 experiences thermal runaway, heat will be transferred directly through the busbar. Therefore, the role of heat insulation element 24 is relatively small, and heat insulation element 24 can be eliminated, thereby improving the space utilization of the battery pack.

[0087] It should be noted that the individual cells 11 of a battery unit 10 can be partially connected in series and partially connected in parallel. The individual cells 11 connected in parallel may not be provided with heat insulation element 24; or, all the individual cells 11 of a battery unit 10 may be connected in parallel, and the individual cells 11 connected in parallel may not be provided with heat insulation element 24.

[0088] In some embodiments, each individual cell 11 of a battery cell 10 may be connected in series.

[0089] In one embodiment, the battery pack further includes a plurality of individual battery cells 11 connected in parallel, and at least some of the individual battery cells 11 connected in parallel are not provided with heat insulation elements 24. That is, in addition to the battery cell 10, the battery pack may also include a plurality of individual battery cells 11 connected in parallel, and at least some of these individual battery cells 11 may not be provided with heat insulation elements 24.

[0090] In one embodiment, in addition to the battery cell 10, the battery pack may also include a plurality of individual cells 11 arranged in parallel, and a heat-conducting element 23 is provided between the individual cells 11 in parallel to ensure reliable heat exchange for the individual cells 11, thereby improving the safe operation performance of the battery pack.

[0091] In one embodiment, when not all adjacent individual cells 11 are provided with heat insulation elements 24, the thickness of the heat insulation elements 24 is ≥2mm. That is, a relatively small number of heat insulation elements 24 can improve the utilization rate of the internal space of the battery pack. Therefore, at the same time, the thickness of the heat insulation elements 24 is increased, thereby improving the heat insulation capacity of the heat insulation elements 24.

[0092] In one embodiment, the single cell 11 uses a ternary cathode material, that is, the single cell 11 can be a ternary system battery, thereby achieving good heat insulation and heat exchange through the separator unit 20, thereby improving the safety performance of the battery pack.

[0093] The single cell 11 can be a ternary lithium battery, with an energy density of 200Wh / kg-300Wh / kg. The energy densities of ternary lithium batteries can be 200Wh / kg, 201Wh / kg, 210Wh / kg, 220Wh / kg, 230Wh / kg, 240Wh / kg, 248Wh / kg, 250Wh / kg, 260Wh / kg, 270Wh / kg, 280Wh / kg, 290Wh / kg, 295Wh / kg, 298Wh / kg, 300Wh / kg, etc.

[0094] In some embodiments, the energy density of a ternary lithium battery can be between 190 Wh / kg and 200 Wh / kg. In some embodiments, it is not excluded that the energy density of a ternary lithium battery can also be less than 190 Wh / kg.

[0095] It should be noted that a single battery cell, comprising a battery cell and an electrolyte, is the smallest unit capable of electrochemical reactions such as charging / discharging. A battery cell refers to a unit formed by winding or laminating stacked portions, which include a first electrode, a separator, and a second electrode. When the first electrode is a positive electrode, the second electrode is a negative electrode. The polarities of the first and second electrodes can be interchanged. Both the first and second electrodes are coated with active materials.

[0096] In one embodiment, a single cell can be a square cell, that is, a square prism cell. A square prism cell mainly refers to a cell with a prism shape, but it is not strictly limited that each side of the prism must be a straight line in the strict sense, and the corners between the sides do not have to be right angles, but can be rounded.

[0097] Individual cells can be stacked cells, which not only facilitates assembly but also allows for the production of longer cells. Specifically, the cell is a stacked cell, which has a first electrode, a second electrode with the opposite electrical charge to the first electrode, and a separator between the first and second electrodes, thereby stacking multiple pairs of first and second electrodes to form a stacked cell.

[0098] Alternatively, a single cell can be a wound cell, which involves winding a first electrode, a second electrode with the opposite electrical charge to the first electrode, and a separator between the first and second electrodes to obtain a wound cell.

[0099] In one embodiment, the battery pack is a battery module or a battery pack.

[0100] The battery module includes multiple individual cells 11, which can be prismatic cells. The battery module may also include end plates and side plates for fixing the multiple individual cells 11.

[0101] The battery pack includes multiple individual cells 11 and a battery housing, which is used to secure the multiple individual cells 11.

[0102] It should be noted that the battery pack includes individual batteries 11, and there can be multiple individual batteries 11, which are housed within the battery casing. Alternatively, the multiple individual batteries 11 can be assembled into a battery module and then installed within the battery casing. Or, the multiple individual batteries 11 can be directly housed within the battery casing, meaning there is no need to group them together; the battery casing can be used to secure the multiple individual batteries 11.

[0103] In some embodiments, there may be multiple battery cells 10, and two adjacent individual cells 11 in multiple battery cells 10 may share a partition unit 20. For example, there may be two battery cells 10. Therefore, a partition unit 20 can be sandwiched between two pairs of individual cells 11 to facilitate the installation of the partition unit 20.

[0104] Alternatively, there can be multiple battery cells 10, and each battery cell 10 can have an independent separator 20 between any two adjacent individual cells 11.

[0105] Combination Figure 1As shown, there can be multiple battery units 10, which are disposed inside the battery housing 30. Furthermore, multiple battery units 10 can share the partition unit 20 and the heat exchange pipeline 40.

[0106] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and exemplary embodiments are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

[0107] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of protection of this disclosure is limited only by the appended claims.

Claims

1. A battery pack, characterized in that, include: The battery cell (10) includes a plurality of individual cells (11), and the stacking direction of the plurality of individual cells (11) is perpendicular to the large surface (111) of the individual cells (11). A separating unit (20) is disposed between two adjacent single cells (11). The two sides of the separating unit (20) include a heat exchange surface (21) and a heat insulation surface (22). The heat exchange surface (21) and the heat insulation surface (22) are respectively in contact with the large surface (111) of the two adjacent single cells (11), so that the separating unit (20) has heat exchange contact with the large surface (111) of one single cell (11) and heat insulation contact with the large surface (111) of the other single cell (11). The battery housing (30) contains multiple battery units (10), and the multiple battery units (10) are disposed within the battery housing (30). The heat exchange pipeline (40) is shared by multiple battery cells (10) and the heat exchange pipeline (40) is shared by multiple battery cells (10).

2. The battery pack according to claim 1, characterized in that, The partition unit (20) includes: A heat-conducting element (23) having the heat exchange surface (21); A heat insulation element (24) having the heat insulation surface (22); The heat-conducting element (23) is connected to the heat-insulating element (24).

3. The battery pack according to claim 2, characterized in that, The heat insulation element (24) is a heat insulation coating, which is disposed on the outer surface of the heat-conducting element (23), or the heat insulation element (24) is a heat insulation pad, which is bonded to the heat-conducting element (23), or the heat insulation element (24) includes a heat insulation pad and a heat insulation coating, which is disposed on the outer surface of the heat insulation pad and / or the outer surface of the heat-conducting element (23).

4. The battery pack according to claim 2 or 3, characterized in that, The heat-conducting element (23) is a metal plate, and a channel (231) is formed inside the metal plate. The battery pack introduces gas or liquid into the channel (231) through the heat exchange pipeline (40). Alternatively, the heat-conducting element (23) is a heating film. Alternatively, the heat-conducting element (23) includes a metal plate and a heating film.

5. The battery pack according to claim 4, characterized in that, The battery pack also includes a metal part (50), which is disposed on the side of the heat insulation element (24) away from the heat conduction element (23) so that the heat insulation surface (22) contacts the large surface (111) of the single cell (11) through the metal part (50); The metal part (50) has a cavity (51) inside.

6. The battery pack according to claim 2, characterized in that, The thermal conductivity of the heat insulation element (24) is ≤0.05W / (m·k), or at least one of the heat-conducting element (23) and the heat insulation element (24) includes a buffer portion to absorb the expansion of the large surface (111) of the single cell (11).

7. The battery pack according to claim 2, characterized in that, The thickness of the thermally conductive element (23) is 3mm-8mm, and / or the thickness of the thermal insulation element (24) is less than 5mm.

8. The battery pack according to claim 7, characterized in that, The thickness of the heat insulation element (24) is ≤3mm, and / or the thickness of the heat insulation element (24) is ≥2mm.

9. The battery pack according to claim 2, characterized in that, The distance between the two ends of the heat-conducting element (23) facing the side wall of the battery box (30) is greater than the distance between the two ends of the heat insulation element (24) facing the side wall of the battery box (30), so as to facilitate the connection of the heat-conducting element (23) with the heat exchange pipeline (40).

10. The battery pack according to claim 1, characterized in that, No heat-conducting element (23) is provided between the heat insulation surface (22) and the large surface (111) of the single cell (11) on the side away from the heat exchange surface (21), or a heat-conducting element (23) is provided between the heat insulation surface (22) and the large surface (111) of the single cell (11) on the side away from the heat exchange surface (21), or at least one of the heat exchange surface (21) and the heat insulation surface (22) is bonded and fixed to the large surface (111) of the single cell (11).

11. The battery pack according to claim 1, characterized in that, The separator (20) is provided between each of the two adjacent single cells (11) so that the two large surfaces of the middle single cell (11) are in contact with the heat exchange surface (21) and the heat insulation surface (22) respectively.

12. The battery pack according to claim 1, characterized in that, Along the stacking direction, at least one of the opposite ends of the battery cell (10) is provided with a heat insulation element (24), or, along the stacking direction, the opposite ends of the battery cell (10) are respectively provided with a heat conduction element (23) and a heat insulation element (24), or, along the stacking direction, the opposite ends of the battery cell (10) are not provided with a heat conduction element (23) or a heat insulation element (24), or, a heat conduction element (23) is provided between adjacent individual cells (11), a heat insulation element (24) is provided between adjacent individual cells (11), the number of heat insulation elements (24) is less than the number of heat conduction elements (23), or, at least some of the individual cells (11) connected in parallel are not provided with a heat insulation element (24), or, the individual cells (11) connected in parallel are provided with a heat conduction element (23).

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