Battery pack and electric device

Abstract

The utility model relates to the field of batteries, and provides a battery pack and an electric device. The battery pack comprises a battery monomer and a box body, the battery monomer is provided with a ventilation pipe fitting, the ventilation pipe fitting extends along the length direction of the battery monomer, and a first air duct penetrating through the battery monomer is formed in an in-pipe space of the ventilation pipe fitting; the box body comprises two end plates, the two end plates are arranged at the two opposite ends of the battery single bodies in the length direction of the battery single bodies respectively, and second air channels communicating with the first air channels in a one-to-one correspondence mode are formed in the end plates in a penetrating mode. Based on the structure, the heat dissipation performance of the battery pack can be optimized and improved, the heat dissipation effect on the battery monomers can be balanced and improved, the phenomenon that the middle heat and the edge heat of the battery monomers are unbalanced can be reduced, the distribution of the heat in the battery monomers can be balanced, and the local overheating phenomenon of the battery monomers can be reduced; the use reliability, the use safety and the service life of the battery pack and the battery monomers can be maintained and improved, and the risk of thermal runaway of the battery pack and the battery monomers can be reduced.

Description

Technical Field

[0001] This application belongs to the technical field of batteries, and particularly relates to a battery pack and an electrical device. Background Art

[0002] A battery pack generally includes a box body, a plurality of battery cells accommodated in the box body, and a liquid cooling plate laid on the bottom of the box body. The liquid cooling plate abuts against each battery cell and exchanges heat. However, the heat dissipation effect of the liquid cooling plate on the battery cells is uneven, resulting in poor heat dissipation performance of the battery pack, and thus poor reliability, safety, and service life of the battery pack. Summary of the Utility Model

[0003] Embodiments of this application provide a battery pack and an electrical device, aiming to solve the problems of poor heat dissipation performance of the battery pack, resulting in poor reliability, safety, and service life of the battery pack.

[0004] To achieve the above object, the technical solution adopted in the embodiments of this application is:

[0005] In a first aspect, a battery pack is provided, including:

[0006] A battery cell is provided with a ventilation pipe fitting, the ventilation pipe fitting extends along the length direction of the battery cell, and the inner space of the ventilation pipe fitting forms a first air duct that penetrates through the battery cell;

[0007] A box body includes two end plates, the two end plates are respectively arranged at opposite ends of the battery cell along the length direction of the battery cell, and the end plates are provided with second air ducts that are in one-to-one correspondence and communication with the first air ducts.

[0008] In some embodiments, the end of the ventilation pipe fitting is hermetically connected to the end plate.

[0009] In some embodiments, the end face of the ventilation pipe fitting abuts against the inner side face of the end plate and is welded.

[0010] In some embodiments, the battery cell includes a housing, an electrode assembly, and two electrode terminals;

[0011] The housing includes a shell and two end caps, the shell extends along the length direction of the battery cell and is cylindrical, the two end caps are respectively installed at opposite ends of the shell, and the end caps are provided with mounting holes;

[0012] The electrode assembly is wound between the outer circumference of the ventilation pipe fitting and the inner circumference of the shell;

[0013] The polarities of the two electrode terminals are opposite. The two electrode terminals are respectively installed through the installation holes of the two end caps. The electrode terminal is electrically connected to the adjacent electrode assembly. The electrode terminal is provided with a through hole, and the ventilation pipe fitting is inserted through the through holes of the two electrode terminals.

[0014] In some embodiments, the battery cell includes a plurality of the electrode assemblies, and the plurality of electrode assemblies are sequentially arranged along the length direction of the battery cell and are sequentially connected in series.

[0015] In some embodiments, the end of the ventilation pipe fitting protrudes from the outer end face of the electrode terminal.

[0016] In some embodiments, a seal is provided between the installation hole and the electrode terminal, and the seal seals the gap between the installation hole and the electrode terminal.

[0017] In some embodiments, the electrode terminal includes a main body portion and a flange portion. The main body portion is installed through the installation hole, and the flange portion is connected to the outer end of the main body portion and extends outward along the circumference of the main body portion;

[0018] The seal surrounds the outer circumference of the main body portion, and the seal seals and abuts against the outer circumferential surface of the main body portion and seals and abuts against the end face of the flange portion facing it.

[0019] In some embodiments, a part of the end cap is embedded in the seal.

[0020] In some embodiments, the battery cell includes an insulating film. The insulating film surrounds the outer circumference of the ventilation pipe fitting. The opposite ends of the insulating film respectively protrude from the outer end faces of the two electrode terminals. The insulating film insulates and isolates the ventilation pipe fitting from the electrode terminal and insulates and isolates the ventilation pipe fitting from the electrode assembly.

[0021] In some embodiments, at least one end of the outer shell is provided with an explosion-proof valve, and the explosion-proof valve is arranged on the periphery of the electrode terminal.

[0022] In some embodiments, at least one end of the outer shell is provided with a liquid injection hole, and the liquid injection hole is arranged on the periphery of the electrode terminal.

[0023] In some embodiments, along the length direction of the battery cell, the projected shape of the first air duct is the same as the projected shape of the battery cell.

[0024] In some embodiments, along the length direction of the battery cell, the projected shape of the second air duct is the same as the projected shape of the first air duct.

[0025] In some embodiments, along the length direction of the battery cell, the projected shape of the first air duct is kidney-shaped.

[0026] In some embodiments, the center line of the ventilation pipe fitting coincides with the center line of the battery cell.

[0027] In a second aspect, an electrical device is provided, including the battery pack provided in the embodiments of the present application.

[0028] The beneficial effects of the battery pack provided in the present application are as follows:

[0029] For the battery pack provided in the embodiments of the present application, by arranging a ventilation pipe fitting on the battery cell, it is convenient to form a first air duct passing through the battery cell via the inner space of the ventilation pipe fitting. And by respectively arranging second air ducts corresponding to and communicating with the first air duct on the two end plates of the box body, it is convenient to connect the first air duct of the battery cell to the outside of the box body via the second air ducts on the two end plates. Based on this, it is convenient for the heat exchange air flow to sequentially flow through the second air duct on one end plate, the first air duct of the battery cell, and the second air duct on the other end plate along the length direction of the battery cell, so as to facilitate the heat exchange between the heat exchange air flow and the box body, the battery cell, etc. during the flow process, and facilitate the heat dissipation of the box body and the battery cell during the flow process of the heat exchange air flow. In particular, since the ventilation pipe fitting is arranged in the middle of the battery cell along the length direction of the battery cell, during the process of the heat exchange air flow flowing through the first air duct, it can directly and quickly take away the heat in the middle of the battery cell, and can diffuse and evenly take away the heat at the edge of the battery cell along the circumferential direction of the ventilation pipe fitting, thereby reducing the phenomenon of uneven heat in the middle and at the edge of the battery cell, balancing the distribution of heat inside the battery cell, and reducing the local overheating phenomenon of the battery cell. Thus, the heat dissipation performance of the battery pack can be optimized and improved, the heat dissipation effect on the battery cell can be balanced and improved, the use reliability, use safety and service life of the battery pack and its battery cell can be maintained and improved, and the risk of thermal runaway of the battery pack and its battery cell can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0031] Figure 1 It is a schematic structural diagram of a battery pack provided in some embodiments of the present application;

[0032] Figure 2 is Figure 1 an enlarged view of the provided Area A;

[0033] Figure 3 The front view of the battery cell provided; Figure 1 The sectional view taken along B - B provided;

[0034] Figure 4 The enlarged view of area C provided; Figure 3 The sectional view taken along B - B provided;

[0035] Figure 5 The enlarged view of area D provided; Figure 4 The enlarged view of area C provided;

[0036] Figure 6 Among them, each reference numeral in the figure: Figure 4 10 - battery cell, 11 - ventilation pipe fitting, 111 - first air duct, 12 - outer shell, 121 - housing, 122 - end cover, 1221 - mounting hole, 13 - electrode assembly, 131 - positive electrode tab, 132 - negative electrode tab; 14 - electrode terminal, 14a - positive electrode terminal, 141 - perforation, 142 - main body portion, 143 - flange portion; 15 - seal, 151 - extension portion, 16 - insulating film, 161 - insulating convex portion, 17 - explosion - proof valve, 18 - liquid injection hole; 20 - box body, 21 - end plate, 211 - second air duct, 212 - cavity; x - length direction of the battery cell, y - thickness direction of the battery cell.

[0037] Among them, each reference numeral in the figure:

[0038] 10 - battery cell, 11 - ventilation pipe fitting, 111 - first air duct, 12 - outer shell, 121 - housing, 122 - end cover, 1221 - mounting hole, 13 - electrode assembly, 131 - positive electrode tab, 132 - negative electrode tab; 14 - electrode terminal, 14a - positive electrode terminal, 141 - perforation, 142 - main body portion, 143 - flange portion; 15 - seal, 151 - extension portion, 16 - insulating film, 161 - insulating convex portion, 17 - explosion - proof valve, 18 - liquid injection hole; 20 - box body, 21 - end plate, 211 - second air duct, 212 - cavity; x - length direction of the battery cell, y - thickness direction of the battery cell. Specific embodiments

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clear and understandable, the following will describe this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0040] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to this application.

[0041] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more unless otherwise specifically defined.

[0042] In this application, unless otherwise clearly defined and limited, terms such as "installed", "connected", "joined", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] In this application, a battery cell is the smallest unit for storing and outputting electric energy. A battery pack is a modular structure including at least two battery cells to provide higher voltage and capacity.

[0044] A battery pack generally includes a box body, a plurality of battery cells accommodated in the box body, and a liquid cooling plate laid on the bottom of the box body. The liquid cooling plate abuts against each battery cell and conducts heat exchange. However, in this way, the heat dissipation effect of the liquid cooling plate on the side of the battery cell where it abuts is better, while the heat dissipation effect on other areas of the battery cell is worse. That is, there is an uneven heat dissipation phenomenon of the liquid cooling plate on the battery cell, resulting in poor heat dissipation performance of the battery pack, and thus the use reliability, use safety, and service life of the battery pack and its battery cells are poor.

[0045] Therefore, the embodiments of this application provide a battery pack, which can optimize the heat dissipation performance, balance and improve the heat dissipation effect on the battery cells, so as to maintain and improve the use reliability, use safety, and service life of the battery pack and its battery cells.

[0046] The following describes the specific implementation of this application in detail with specific embodiments:

[0047] Please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4, some embodiments of the present application provide a battery pack, including battery cells 10 and a box body 20. The battery cells 10 are provided with ventilation pipe fittings 11. The ventilation pipe fittings 11 extend along the length direction x of the battery cells 10. The inner space of the ventilation pipe fittings 11 forms a first air duct 111 that penetrates the battery cells 10. The box body 20 includes two end plates 21. The two end plates 21 are respectively arranged at opposite ends of the battery cells 10 along the length direction x of the battery cells 10. The end plates 21 are provided with second air ducts 211 that are in one-to-one correspondence and communicate with the first air duct 111.

[0048] It should be noted that the box body 20 is used to provide a receiving space for the battery cells 10, that is, the battery cells 10 are received in the box body 20. The box body 20 can dust-proof, waterproof, and protect components such as the battery cells 10 received therein, can reduce the influence of external liquids or other foreign objects on the effectiveness and performance of components such as the battery cells 10, and can effectively extend the service life of the battery pack. Among them, the box body 20 can adopt various structures. In some embodiments, the box body 20 can include a frame body, and the frame body is a frame-shaped structure formed by enclosing the frame bars end to end. The frame body can enclose and define a receiving space for receiving the battery cells 10. Among them, the box body 20 can be of various shapes, such as a cuboid, etc. Among them, the box body 20 can adopt various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0049] The battery cells 10 are the smallest units for storing and outputting electric energy. Inside the box body 20, one battery cell 10 can be provided, or at least two battery cells 10 can be provided. In the case where at least two battery cells 10 are provided, the multiple battery cells 10 can be arranged side by side along their thickness direction y. The multiple battery cells 10 can be connected in series, in parallel, or in a mixed connection. Among them, the mixed connection means that there are both series and parallel connections. Among them, the thickness direction y of the battery cells 10 is perpendicular to the length direction x of the battery cells 10.

[0050] It should also be noted that the battery cells 10 are provided with ventilation pipe fittings 11. The ventilation pipe fittings 11 extend along the length direction x of the battery cells 10 and penetrate through the middle of the end faces of the battery cells 10. The ventilation pipe fittings 11 are of a tubular structure. The inner space of the ventilation pipe fittings 11 can form a first air duct 111. The first air duct 111 penetrates the battery cells 10 along the length direction x of the battery cells 10, that is, both opposite ends of the first air duct 111 communicate to the outside of the battery cells 10. The first air duct 111 can be used for flowing heat exchange airflows.

[0051] The box body 20 is provided with two end plates 21. One of the end plates 21 is arranged at one end of the battery cells 10 along the length direction x of the battery cells 10, and the other end plate 21 is arranged at the other end of the battery cells 10 along the length direction x of the battery cells 10. The end plates 21 can extend along the thickness direction y of the battery cells 10 (that is, the side-by-side direction of the multiple battery cells 10).

[0052] The end plate 21 is provided with second air ducts 211 that are arranged in one-to-one correspondence with the first air ducts 111 of the battery cell 10. The multiple second air ducts 211 on the end plate 21 are arranged at intervals along the thickness direction y of the battery cell 10. The second air ducts 211 penetrate the end plate 21 along the length direction x of the battery cell 10.

[0053] Based on this, it is convenient for the heat exchange air flow to flow through the second air ducts 211 of one end plate 21, the first air ducts 111 of the battery cell 10, and the second air ducts 211 of the other end plate 21 in sequence along the length direction x of the battery cell 10. Thus, it is convenient for the heat exchange air flow to perform heat exchange with the box body 20, the battery cell 10, etc. during the flowing process, and in particular, it is convenient for the heat exchange air flow to dissipate heat from the box body 20 and the battery cell 10 during the flowing process.

[0054] Among them, the heat exchange air flow can be but is not limited to air, etc.

[0055] Among them, along the length direction x of the battery cell 10, the projected shape of the first air duct 111 and the projected shape of the second air duct 211 can be set to be the same or different. The projected shape of the first air duct 111 can be set as required (for example, it can be set to be circular, kidney-shaped, rectangular, etc.), and the projected shape of the second air duct 211 can be set as required (for example, it can be set to be circular, kidney-shaped, rectangular, etc.).

[0056] In summary, for the battery pack provided in the embodiment of the present application, by arranging the ventilation pipe fitting 11 on the battery cell 10, the first air duct 111 passing through the battery cell 10 can be formed through the inner space of the ventilation pipe fitting 11. And by arranging the two end plates 21 of the box body 20 to be respectively provided with the second air ducts 211 corresponding to and communicating with the first air duct 111, the first air duct 111 of the battery cell 10 can be communicated to the outside of the box body 20 through the second air ducts 211 of the two end plates 21. Based on this, it is convenient for the heat exchange air flow to sequentially flow through the second air duct 211 of one end plate 21, the first air duct 111 of the battery cell 10, and the second air duct 211 of the other end plate 21 along the length direction x of the battery cell 10, so that it is convenient for the heat exchange air flow to perform heat exchange with the box body 20, the battery cell 10, etc. during the flowing process, and it is convenient for the heat exchange air flow to dissipate heat from the box body 20 and the battery cell 10 during the flowing process. In particular, since the ventilation pipe fitting 11 is arranged in the middle of the battery cell 10 along the length direction x of the battery cell 10, during the process of the heat exchange air flow flowing through the first air duct 111, the heat in the middle of the battery cell 10 can be directly and quickly taken away, and the heat at the edge of the battery cell 10 can be diffused and evenly taken away along the circumferential direction of the ventilation pipe fitting 11, so that the phenomenon of uneven heat between the middle and the edge of the battery cell 10 can be reduced, the distribution of heat inside the battery cell 10 can be balanced, and the local overheating phenomenon of the battery cell 10 can be reduced. Thus, the heat dissipation performance of the battery pack can be optimized and improved, the heat dissipation effect on the battery cell 10 can be balanced and improved, the use reliability, use safety and service life of the battery pack and its battery cell 10 can be maintained and improved, and the risk of thermal runaway of the battery pack and its battery cell 10 can be reduced.

[0057] Please refer to Figure 1 、 Figure 2 、 Figure 3 In some embodiments of the present application, a cavity 212 is provided inside the end plate 21. The cavity 212 extends along the extending direction of the end plate 21 and communicates with each second air duct 211 of the end plate 21.

[0058] It should be noted that the extending direction of the end plate 21 corresponds to the thickness direction y of the battery cell 10, that is, the direction of a plurality of battery cells 10 arranged side by side. The cavity 212 extends along the extending direction of the end plate 21 and even penetrates the end plate 21. In some embodiments, the end plate 21 can be made of a hollow profile, and the cavity 212 is obtained based on the hollow of the hollow profile.

[0059] The cavity 212 can communicate with each second air duct 211 of the end plate 21, so that each second air duct 211 of the end plate 21 can communicate with each other and exchange heat exchange air flow.

[0060] By adopting the above solution, the end plate 21 can communicate with each second air duct 211 of the end plate 21 via the cavity 212, so as to enable the second air ducts 211 of the end plate 21 to communicate with each other and exchange heat transfer air flow. Based on this, the heat transfer air flow can flow along the cavity 212 through any second air duct 211 of the end plate 21, and thus quickly flow outside the box body 20 and the first air ducts 111 of each battery cell 10. Thereby, the circulation efficiency and heat transfer efficiency of the heat transfer air flow inside and outside the battery pack can be improved, the heat dissipation performance of the battery pack can be improved, and the use reliability, use safety and service life of the battery pack and its battery cells 10 can be improved. Moreover, based on the design of the cavity 212, the weight of the end plate 21 can be correspondingly reduced, thereby reducing the weight of the battery pack and improving the energy density of the battery pack.

[0061] Please refer to Figure 1 、 Figure 2 、 Figure 3 , in some embodiments of the present application, the end of the ventilation pipe fitting 11 is hermetically connected to the end plate 21.

[0062] It should be noted that the end of the ventilation pipe fitting 11 is the end of the ventilation pipe fitting 11 along the length direction x of the battery cell 10. The end of the ventilation pipe fitting 11 is connected to the end plate 21, and the connection method can be a fixed connection (such as welding, bonding, etc.) or a detachable connection (such as bolt connection, etc.). The end face of the ventilation pipe fitting 11 is directly hermetically abutted against the inner side face of the end plate 21 or indirectly hermetically connected via other sealing structures (such as sealing rings).

[0063] By adopting the above solution, by hermetically connecting the end of the ventilation pipe fitting 11 to the end plate 21, the installation position and installation state of the ventilation pipe fitting 11 relative to the end plate 21 can be stabilized, the relative position between the first air duct 111 of the ventilation pipe fitting 11 and the second air duct 211 of the end plate 21 can be accurately positioned and reliably stabilized, and the corresponding first air duct 111 and second air duct 211 can be hermetically docked. Based on this, it is convenient for the heat transfer air flow to quickly and smoothly flow through the corresponding first air duct 111 and second air duct 211, the leakage of the heat transfer air flow from the connection between the ventilation pipe fitting 11 and the end plate 21 and the flow to other areas of the box body 20 can be blocked, the circulation efficiency and heat transfer efficiency of the heat transfer air flow in the first air duct 111 and the second air duct 211 can be improved, the heat transfer path and heat transfer time can be shortened, thereby improving the heat dissipation performance of the battery pack and the use reliability, use safety and service life of the battery pack and its battery cells 10.

[0064] Moreover, based on the connection relationship between the ventilation pipe fitting 11 and the two end plates 21, the ventilation pipe fitting 11 can be urged to form a beam structure (which can also be understood as a longitudinal beam) between the two end plates 21. At this time, the two end plates 21 are equivalent to cross beams, thereby improving the structural strength, structural stability and structural reliability of the battery pack, and improving the resistance performance of the battery pack to vibration and impact. At the same time, since the ventilation pipe fitting 11 forms a beam structure between the two end plates 21, that is, the ventilation pipe fitting 11 itself can be used as the longitudinal beam of the battery pack, therefore, the separately provided longitudinal beam structure can be omitted from the battery pack housing 20, and even the supporting structure for supporting the battery cells 10 can be omitted. Based on this, the structural design of the housing 20 and the battery pack can be simplified, the components of the housing 20 and the battery pack can be effectively reduced, the weight of the battery pack can be reduced, and the energy density of the battery pack can be increased.

[0065] Moreover, based on the sealed docking of the first air duct 111 and the second air duct 211, on the basis of facilitating the flow of the heat exchange air flow, the sealing performance of the inside of the battery pack relative to the outside can be improved, thereby preventing external impurities such as dust and moisture from invading the housing 20 through the gap between the ventilation pipe fitting 11 and the end plate 21, maintaining the stability of the internal environment of the battery pack, and improving the use reliability, use safety and service life of the battery pack and its battery cells 10.

[0066] Please refer to Figure 1 、 Figure 2 、 Figure 3 In some embodiments of the present application, the end face of the ventilation pipe fitting 11 abuts and is welded to the inner side face of the end plate 21.

[0067] By adopting the above solution, by making the end face of the ventilation pipe fitting 11 abut against and be welded to the inner side face of the end plate 21, on the one hand, seamless connection and sealed connection between the ventilation pipe fitting 11 and the end plate 21 can be directly achieved through abutting and welding. Based on this, the connection convenience and connection efficiency of the sealed connection between the ventilation pipe fitting 11 and the end plate 21 can be improved, and the reliability of the sealed butt joint between the first air duct 111 and the second air duct 211 can be improved. Thus, external impurities such as dust and moisture can be prevented from invading the box body 20 through the connection part between the ventilation pipe fitting 11 and the end plate 21, the stability of the internal environment of the battery pack can be maintained, and the use reliability, use safety and service life of the battery pack and its battery cells 10 can be improved. On the one hand, the connection strength and connection reliability between the ventilation pipe fitting 11 and the end plate 21 can be improved, thereby improving the structural strength, structural stability and structural reliability of the battery pack, and improving the resistance performance of the battery pack to vibration and impact. On the one hand, it can prompt the end face of the ventilation pipe fitting 11 to closely fit the inner side face of the end plate 21, facilitate the rapid and smooth flow of the heat exchange air flow through the corresponding first air duct 111 and second air duct 211, improve the circulation efficiency and heat exchange efficiency of the heat exchange air flow in the first air duct 111 and the second air duct 211, thereby improving the heat dissipation performance of the battery pack, and improving the use reliability, use safety and service life of the battery pack and its battery cells 10.

[0068] Please refer to Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 In some embodiments of the present application, the battery cell 10 includes a housing 12, an electrode assembly 13 and two electrode terminals 14. The housing 12 includes a shell 121 and two end caps 122. The shell 121 extends along the length direction x of the battery cell 10 and is cylindrical. The two end caps 122 are respectively installed at opposite ends of the shell 121, and the end caps 122 are provided with mounting holes 1221 in a penetrating manner. The electrode assembly 13 is wound between the outer circumference of the ventilation pipe fitting 11 and the inner circumference of the shell 121. The polarities of the two electrode terminals 14 are opposite. The two electrode terminals 14 are respectively inserted and installed in the mounting holes 1221 of the two end caps 122. The electrode terminal 14 is electrically connected to the adjacent electrode assembly 13. The electrode terminal 14 is provided with a through hole 141, and the ventilation pipe fitting 11 is inserted through the through holes 141 of the two electrode terminals 14.

[0069] It should be noted that the shell 121 extends along the length direction x of the battery cell 10, and the shell 121 is cylindrical, such as cylindrical, waist-shaped cylindrical or polygonal cylindrical. There are two end caps 122, and the two end caps 122 are respectively installed at the two barrel openings at opposite ends of the shell 121 along the length direction x of the battery cell 10. Both of the two end caps 122 are provided with mounting holes 1221, and the mounting holes 1221 penetrate the end caps 122 along the length direction x of the battery cell 10.

[0070] The electrode terminals 14 (also known as pole columns) are components for outputting or inputting electrical energy. There are two electrode terminals 14, and the polarities of the two electrode terminals 14 are opposite, that is, one of the electrode terminals 14 is the positive electrode terminal 14a, and the other electrode terminal 14 is the negative electrode terminal. The two electrode terminals 14 are respectively installed in the mounting holes 1221 of the two end caps 122, so that the two electrode terminals 14 are both stably installed in position and state relative to the housing 12.

[0071] Both of the two electrode terminals 14 are provided with through holes 141, and the through holes 141 penetrate the electrode terminals 14 along the length direction x of the battery cell 10. The ventilation pipe fitting 11 is inserted into the through holes 141 of the two electrode terminals 14.

[0072] Based on this, the housing 121, the two end caps 122, the ventilation pipe fitting 11, and the two electrode terminals 14 can jointly enclose an internal space, which can be basically isolated from the external environment of the battery cell 10, and this internal space can be used to accommodate and protect at least one electrode assembly 13.

[0073] It should also be noted that the electrode assembly 13 is a component in the battery cell 10 where an electrochemical reaction occurs. The electrode assembly 13 includes two sets of electrode plates with opposite polarities and a separator. The two sets of electrode plates with opposite polarities are the positive electrode plate and the negative electrode plate respectively, and the separator separates the positive electrode plate and the negative electrode plate. The positive electrode plate, the separator, and the negative electrode plate can be processed in a winding manner to form the electrode assembly 13. The electrode assembly 13 is wound and arranged between the outer periphery of the ventilation pipe fitting 11 and the inner periphery of the housing 121.

[0074] In the electrode assembly 13, the part of the positive electrode plate without active material constitutes the positive electrode tab 131, and the part of the negative electrode plate without active material constitutes the negative electrode tab 132. The positive electrode tab 131 and the negative electrode tab 132 are the current transmission ends of the electrode assembly 13 for transmitting current. The positive electrode tab 131 and the negative electrode tab 132 are respectively located at both ends of the electrode assembly 13 along the length direction x of the battery cell 10.

[0075] The electrode terminal 14 is electrically connected to the adjacent electrode assembly 13. That is, the positive electrode terminal 14a is electrically connected to the positive electrode tab 131 of the adjacent electrode assembly 13, and the negative electrode terminal is electrically connected to the negative electrode tab 132 of the adjacent electrode assembly 13. Among them, the electrode terminal 14 and the adjacent electrode assembly 13 can be directly electrically connected or indirectly electrically connected via other components (such as a transfer piece), and the electrical connection method can be achieved by welding or other methods, which is not limited to this.

[0076] By adopting the above solution, an internal space that is basically isolated from the external environment can be formed jointly by the housing 121, the two end caps 122, the ventilation pipe fitting 11, and the two electrode terminals 14, so as to accommodate and protect at least one electrode assembly 13 via this internal space. And based on the electrical connection relationship between the electrode terminal 14 and the adjacent electrode assembly 13, the input (i.e., storage) and output of electric energy can be realized. Based on this, a modular, integrated, and structurally optimized battery cell 10 can be formed, which can maintain and improve the service performance and electrochemical performance of the battery cell 10.

[0077] Moreover, in combination with the design that "the electrode assembly 13 is wound between the outer circumference of the ventilation pipe fitting 11 and the inner circumference of the housing 121", during the process of the heat exchange air flow passing through the first air duct 111 of the ventilation pipe fitting 11, it is also convenient for the heat exchange air flow to directly and quickly adjust the heat in the middle of the electrode assembly 13 and the heat in the middle of the electrode terminal 14, and it is convenient for the heat exchange air flow to diffuse along the circumferential direction of the ventilation pipe fitting 11 and evenly adjust the heat at the edge of the electrode assembly 13 and the heat at the edge of the electrode terminal 14. Thus, the phenomenon of uneven heat in the middle and at the edge of the electrode assembly 13 and the electrode terminal 14 can be reduced, the distribution of heat inside the battery cell 10 can be balanced, and the local overheating phenomenon of the battery cell 10 can be reduced. Thereby, the risk of thermal runaway of the battery cell 10 can be reduced, and the performance stability, service reliability, service safety, and service life of the battery cell 10 can be improved.

[0078] Please refer to Figure 4 、 Figure 5 、 Figure 6 , in some embodiments of the present application, the battery cell 10 includes a plurality of electrode assemblies 13, and the plurality of electrode assemblies 13 are sequentially arranged and sequentially connected in series along the length direction x of the battery cell 10.

[0079] It should be noted that a plurality of electrode assemblies 13 are provided inside the outer shell 12, and the plurality of electrode assemblies 13 are all wound between the outer circumference of the ventilation pipe fitting 11 and the inner circumference of the housing 121. The plurality of electrode assemblies 13 are sequentially arranged along the length direction x of the battery cell 10.

[0080] The positive electrode tabs 131 of all the electrode assemblies 13 are all arranged at one end of the electrode assembly 13 facing the positive electrode terminal 14a. The negative electrode tabs 132 of all the electrode assemblies 13 are all arranged at one end of the electrode assembly 13 facing the negative electrode terminal. Based on this, between two adjacent electrode assemblies 13, the negative electrode tab 132 of one electrode assembly 13 and the positive electrode tab 131 of the other electrode assembly 13 can face each other to establish an electrical connection, so that two adjacent electrode assemblies 13 are connected in series. And so on, each electrode assembly 13 can be sequentially connected in series along the axial direction of the outer shell 12. Among them, between the negative electrode tab 132 of the electrode assembly 13 and the positive electrode tab 131 of the adjacent electrode assembly 13, the electrical connection can be realized by, but not limited to, welding and other methods.

[0081] The electrode assembly 13 closest to the positive electrode terminal 14a can orient its positive electrode tab 131 towards the positive electrode terminal 14a, facilitating the electrical connection between the positive electrode terminal 14a and the positive electrode tab 131 of the adjacent electrode assembly 13. The electrode assembly 13 closest to the negative electrode terminal can orient its negative electrode tab 132 towards the negative electrode terminal, facilitating the electrical connection between the negative electrode terminal and the negative electrode tab 132 of the adjacent electrode assembly 13. Thus, it is convenient to electrically connect the two electrode terminals 14 to each electrode assembly 13, facilitating the output or input of electrical energy.

[0082] By adopting the above solution, the output voltage of the battery cell 10 can be equal to the sum of the voltages of the multiple electrode assemblies 13. Based on this, compared with the existing battery cell 10, the battery cell 10 provided in this embodiment can increase its own output voltage. Thus, the number of battery cells 10 and the number of connection nodes in the battery pack can be reduced, the node connection workload can be reduced, the assembly efficiency of the battery pack can be improved, the risk of poor node connection can be reduced, the current and internal resistance of the battery pack can be made to meet the requirements, and the overall performance and safety performance of the battery pack can be maintained and improved.

[0083] Moreover, based on the series connection relationship between the two electrode terminals 14 and each electrode assembly 13, the current path can be shortened, the energy loss of the battery cell 10 during charge and discharge can be reduced, and the energy transfer efficiency can be improved.

[0084] Please refer to Figure 1 、 Figure 4 、 Figure 5 , in some embodiments of the present application, the end of the ventilation pipe fitting 11 protrudes from the outer end face of the electrode terminal 14. It should be noted that the outer end face of the electrode terminal 14 is the end face of the electrode terminal 14 facing the outside of the battery cell 10.

[0085] By adopting the above solution, by making the end of the ventilation pipe fitting 11 protrude from the outer end face of the electrode terminal 14, it is convenient for the ventilation pipe fitting 11 to be connected to the end plate 21 of the battery pack via the part protruding from the outer end face of the electrode terminal 14 and communicate with the second air duct 211 of the end plate 21. Thus, the connection convenience between the ventilation pipe fitting 11 of the battery cell 10 and the end plate 21 of the battery pack can be improved, the flow and distribution of the heat exchange air flow in the battery pack can be promoted, and the assembly convenience and heat dissipation performance of the battery pack can be improved.

[0086] Of course, in other embodiments, the end of the ventilation pipe fitting 11 can be substantially flush with the outer end face of the electrode terminal 14.

[0087] Please refer to Figure 4 、 Figure 5, in some embodiments of the present application, a seal 15 is provided between the mounting hole 1221 and the electrode terminal 14, and the seal 15 seals the gap between the mounting hole 1221 and the electrode terminal 14.

[0088] It should be noted that the seal 15 is a component with sealing performance. The seal 15 is arranged in a ring shape and is sleeved between the outer periphery of the electrode terminal 14 and the mounting hole 1221. The seal 15 seals the gap between the outer periphery of the electrode terminal 14 and the mounting hole 1221. Corresponding to the two electrode terminals 14, two seals 15 are also correspondingly provided.

[0089] By adopting the above solution, the gap between the outer periphery of the electrode terminal 14 and the mounting hole 1221 can be sealed by the seal 15 to improve the sealing performance between the outer periphery of the electrode terminal 14 and the mounting hole 1221. Based on this, it is possible to prevent the liquid (such as electrolyte) in the battery cell 10 from leaking out through the gap between the outer periphery of the electrode terminal 14 and the mounting hole 1221, prevent the gas generated during the charging and discharging process of the battery cell 10 from overflowing through the gap between the outer periphery of the electrode terminal 14 and the mounting hole 1221, and prevent external dust, moisture and other impurities from invading the inside of the battery cell 10 through the gap between the outer periphery of the electrode terminal 14 and the mounting hole 1221. Thus, the risk of the battery cell 10 reducing its performance and having safety hazards due to liquid leakage, gas overflow and impurity pollution can be reduced, the stability of the internal environment of the battery cell 10 can be maintained, and the use reliability, use safety and service life of the battery cell 10 can be improved.

[0090] In some embodiments, the seal 15 is an insulating sealant. With such a setting, the seal 15 can be made to have insulating properties, and electrical insulation can be achieved between the outer periphery of the electrode terminal 14 and the end cover 122 through the seal 15. Of course, in other embodiments, electrical insulation can be achieved between the outer periphery of the electrode terminal 14 and the end cover 122 through other components (such as an insulating coating).

[0091] Please refer to Figure 4 、 Figure 5 , in some embodiments of the present application, the electrode terminal 14 includes a main body portion 142 and a flange portion 143. The main body portion 142 is inserted and installed in the mounting hole 1221, and the flange portion 143 is connected to the outer end of the main body portion 142 and extends outward along the circumference of the main body portion 142. The seal 15 surrounds the outer periphery of the main body portion 142, and the seal 15 seals and abuts against the outer peripheral surface of the main body portion 142 and seals and abuts against the end face of the flange portion 143 facing it.

[0092] It should be noted that the main body portion 142 of the electrode terminal 14 is inserted and installed in the mounting hole 1221 and is electrically connected to the adjacent electrode assembly 13. The flange portion 143 of the electrode terminal 14 is connected to the outer end of the main body portion 142 near the outside of the battery cell 10. The flange portion 143 extends outward along the circumferential direction of the main body portion 142 relative to the main body portion 142, so that a stepped structure is formed between the flange portion 143 and the main body portion 142.

[0093] The seal 15 is arranged in a ring shape and is sleeved between the outer circumference of the main body portion 142 and the mounting hole 1221. The inner ring surface of the seal 15 is sealingly abutted against the outer peripheral surface of the main body portion 142. The side surface of the seal 15 facing the flange portion 143 is sealingly abutted against the side surface of the flange portion 143 facing the seal 15.

[0094] By adopting the above scheme, the inner ring surface of the seal 15 can be sealingly abutted against the outer peripheral surface of the main body portion 142, and the side surfaces of the seal 15 and the flange portion 143 facing each other can be sealingly abutted against each other. Based on this, two sealing surfaces can be formed between the seal 15 and the electrode terminal 14, the sealing area between the seal 15 and the electrode terminal 14 can be increased, the tightness, durability, reliability and stability of the sealing connection between the seal 15 and the electrode terminal 14 can be improved, the risk of loosening or displacement of the seal 15 relative to the electrode terminal 14 can be reduced, thereby the sealing reliability of the seal 15 between the electrode terminal 14 and the mounting hole 1221 can be improved, and the risk of seal failure of the seal 15 can be reduced.

[0095] Of course, in other embodiments, the electrode terminal 14 can adopt other structural designs. For example, the flange portion 143 of the electrode terminal 14 can be omitted. For another example, the electrode terminal 14 can be provided with more parts to form more stepped structures. For another example, a groove for installing the seal 15 can be opened on the outer peripheral surface of the electrode terminal 14.

[0096] Please refer to Figure 4 、 Figure 5 , in some embodiments of the present application, a part of the end cover 122 is embedded in the seal 15. It should be noted that a part of the end cover 122, especially the part along the edge of the mounting hole 1221, is embedded in the seal 15.

[0097] By adopting the above scheme, by embedding a part of the end cover 122 (especially the part along the edge of the mounting hole 1221) in the seal 15, the connection tightness and connection strength between the end cover 122 and the seal 15 can be enhanced. Based on this, the tightness, durability, reliability and stability of the sealing connection between the seal 15 and the end cover 122 can be improved, thereby the sealing reliability of the seal 15 between the electrode terminal 14 and the mounting hole 1221 can be improved, and the risk of seal failure of the seal 15 can be reduced.

[0098] Of course, in other embodiments, the edge of the mounting hole 1221 may be in sealing contact with the outer periphery of the seal 15. Alternatively, other components may be sealingly mounted within the mounting hole 1221 and embedded in the seal 15 to maintain the reliability of the sealed connection between the seal 15 and the end cap 122 via the other components.

[0099] In some embodiments, a sealing treatment may be performed between the perforation 141 and the ventilation pipe fitting 11. For example, a sealant may be applied to the outer edge of the perforation 141, or alternatively, a sealing ring may be sleeved between the hole wall of the perforation 141 and the outer periphery of the ventilation pipe fitting 11.

[0100] Please refer to Figure 4 、 Figure 5 、 Figure 6 In some embodiments of the present application, the battery cell 10 includes an insulating film 16. The insulating film 16 surrounds the outer periphery of the ventilation pipe fitting 11. The opposite ends of the insulating film 16 respectively protrude from the outer end faces of the two electrode terminals 14. The insulating film 16 insulates and isolates the ventilation pipe fitting 11 from the electrode terminals 14, and also insulates and isolates the ventilation pipe fitting 11 from the electrode assembly 13.

[0101] It should be noted that the insulating film 16 is a film-like structure with insulating properties. The insulating film 16 surrounds and winds around the outer periphery of the ventilation pipe fitting 11.

[0102] Along the length direction x of the battery cell 10, the opposite ends of the insulating film 16 respectively protrude from the outer end faces of the two electrode terminals 14. Based on this, the insulating film 16 can cover the area of the outer periphery of the ventilation pipe fitting 11 corresponding to the electrode assembly 13 to insulate and isolate the ventilation pipe fitting 11 from the electrode assembly 13, thereby promoting electrical insulation between the ventilation pipe fitting 11 and the electrode assembly 13. The insulating film 16 can also cover the area of the outer periphery of the ventilation pipe fitting 11 corresponding to the electrode terminals 14 to insulate and isolate the ventilation pipe fitting 11 from the electrode terminals 14, thereby promoting electrical insulation between the ventilation pipe fitting 11 and the electrode terminals 14.

[0103] By adopting the above solution, the insulating film 16 wound around the outer periphery of the ventilation pipe fitting 11 can insulate and isolate the ventilation pipe fitting 11 from the electrode assembly 13 and also insulate and isolate the ventilation pipe fitting 11 from the electrode terminals 14. Based on this, electrical insulation can be promoted between the ventilation pipe fitting 11 and the electrode assembly 13 and the electrode terminals 14 respectively, the short-circuit risk between the ventilation pipe fitting 11 and the electrode assembly 13 and between the ventilation pipe fitting 11 and the electrode terminals 14 can be reduced, and the reliability, safety, and service life of the battery cell 10 can be improved.

[0104] Of course, in other embodiments, electrical insulation between the ventilation pipe fitting 11 and the electrode terminals 14, or between the ventilation pipe fitting 11 and the electrode assembly 13, may be achieved via other components (such as an insulating coating).

[0105] Please refer toFigure 4 , Figure 6 , in some embodiments of the present application, when the battery cell 10 includes a plurality of electrode assemblies 13, and the plurality of electrode assemblies 13 are sequentially arranged along the length direction x of the battery cell 10 and are sequentially connected in series, the insulating film 16 is provided with an insulating convex portion 161. The insulating convex portion 161 is arranged in a ring shape and is disposed between two adjacent electrode assemblies 13, and electrically insulates the two adjacent electrode assemblies 13 from each other.

[0106] It should be noted that the insulating film 16 can increase its winding thickness between two adjacent electrode assemblies 13 to form a ring-shaped insulating convex portion 161. The insulating convex portion 161 can be disposed between two adjacent electrode assemblies 13 and can electrically insulate the two adjacent electrode assemblies 13 from each other.

[0107] By adopting the above solution, an insulating barrier can be formed between two adjacent electrode assemblies 13 through the ring-shaped insulating convex portion 161 disposed between the two adjacent electrode assemblies 13, so as to electrically insulate the two adjacent electrode assemblies 13 from each other. Based on this, the risk of short circuit caused by direct contact between two adjacent electrode assemblies 13 can be reduced, and the service reliability, service safety and service life of the battery cell 10 can be improved. Moreover, the setting of the insulating convex portion 161 can also play a role in limiting and positioning two adjacent electrode assemblies 13 to a certain extent, so that the positions of the plurality of electrode assemblies 13 on the outer periphery of the ventilation pipe fitting 11 can be stabilized, and the structural reliability and structural stability of the battery cell 10 can be improved.

[0108] Of course, in other embodiments, a convex portion can be provided on the outer periphery of the ventilation pipe fitting 11 between two adjacent electrode assemblies 13, and the portion of the insulating film 16 wound around the convex portion can also play the role of "electrically insulating two adjacent electrode assemblies 13 from each other".

[0109] Please refer to Figure 3 , in some embodiments of the present application, at least one end of the outer shell 12 is provided with an explosion-proof valve 17, and the explosion-proof valve 17 is disposed on the periphery of the electrode terminal 14.

[0110] It should be noted that the explosion-proof valve 17 is provided at one end or opposite ends of the outer shell 12 along the length direction x of the battery cell 10. The explosion-proof valve 17 is disposed on the periphery of the electrode terminal 14. Based on this, the explosion-proof valve 17 can correspond to the space where the electrode assembly 13 is located. The explosion-proof valve 17 can be used to release the internal pressure when the internal pressure (or temperature) of the battery cell 10 reaches a threshold value.

[0111] By adopting the above solution, an explosion-proof valve 17 can be provided at one end or opposite ends of the housing 12 along the length direction x of the battery cell 10, on the circumferential side of the electrode terminal 14. Based on this, the explosion-proof valve 17 can be made to correspond to the space where the electrode assembly 13 is located, so as to facilitate discharging the internal pressure through the explosion-proof valve 17 when the internal pressure (or temperature) in the space where the electrode assembly 13 is located reaches the threshold value, thereby improving the use reliability, use safety and service life of the battery cell 10.

[0112] Of course, in other embodiments, the explosion-proof valve 17 can be provided on other wall portions of the housing 12.

[0113] Please refer to Figure 3 、 Figure 4 、 Figure 5 In some embodiments of the present application, at least one end of the housing 12 is provided with a liquid injection hole 18, and the liquid injection hole 18 is provided on the circumferential side of the electrode terminal 14.

[0114] It should be noted that the liquid injection hole 18 is provided at one end or opposite ends of the housing 12 along the length direction x of the battery cell 10. The liquid injection hole 18 is provided on the circumferential side of the electrode terminal 14. Based on this, the liquid injection hole 18 can be made to correspond to the space where the electrode assembly 13 is located. The liquid injection hole 18 can be used to inject electrolyte into the space where the electrode assembly 13 is located.

[0115] By adopting the above solution, a liquid injection hole 18 can be provided at one end or opposite ends of the housing 12 along the length direction x of the battery cell 10, on the circumferential side of the electrode terminal 14. Based on this, the liquid injection hole 18 can be made to correspond to the space where the electrode assembly 13 is located, so as to facilitate injecting electrolyte into the space where the electrode assembly 13 is located when the battery cell 10 is basically assembled, thereby maintaining the use performance and electrochemical performance of the battery cell 10.

[0116] Such as Figure 3 、 Figure 5 As shown, in some embodiments, the seal 15 is provided with an extension portion 151, and the extension portion 151 is provided inside the liquid injection hole 18 and is used to cooperate to seal the liquid injection hole 18 after the liquid injection is completed.

[0117] Of course, in other embodiments, the liquid injection hole 18 can be provided on other wall portions of the housing 12.

[0118] Please refer to Figure 3 、 Figure 4 In some embodiments of the present application, along the length direction x of the battery cell 10, the projected shape of the first air duct 111 is the same as the projected shape of the battery cell 10. For example, along the length direction x of the battery cell 10, the projected shapes of both the first air duct 111 and the battery cell 10 are circular or kidney-shaped, etc.

[0119] By adopting the above solution, the projection shape of the first air duct 111 along the length direction x of the battery cell 10 can be made the same as the projection shape of the battery cell 10 along its length direction x. Based on this, the heat exchange airflow flowing in the first air duct 111 can be diffused along the circumference of the ventilation pipe 11 and evenly take away the heat of each area of ​​the battery cell 10, so as to balance the heat dissipation effect of each area of ​​the battery cell 10, improve the heat dissipation efficiency, and optimize and improve the heat dissipation performance of the battery pack.

[0120] Of course, in other embodiments, the projection shape of the first air duct 111 along the length direction x of the battery cell 10 may be different from the projection shape of the battery cell 10 along its length direction x.

[0121] See also Figure 1 , Figure 2 , Figure 3 In some embodiments of the present application, along the length direction x of the battery cell 10, the projection shape of the second air duct 211 is the same as the projection shape of the first air duct 111. For example, along the length direction x of the battery cell 10, the projection shape of the second air duct 211 and the projection shape of the first air duct 111 are both circular or waist-shaped.

[0122] By adopting the above solution, the projection shape of the second air duct 211 along the length direction x of the battery cell 10 can be made the same as the projection shape of the first air duct 111 along the length direction x of the battery cell 10. Based on this, the shape of the second air duct 211 can be made to match the shape of the first air duct 111, and the heat exchange airflow can be made to flow smoothly and transition smoothly between the second air duct 211 and the first air duct 111, and the expansion and contraction of the heat exchange airflow caused by the difference in shape between the second air duct 211 and the first air duct 111 can be reduced, and the flow resistance of the heat exchange airflow can be reduced, and the circulation efficiency and heat exchange efficiency of the heat exchange airflow can be improved, thereby improving the heat dissipation performance of the battery pack.

[0123] Furthermore, the shape of the second air duct 211 matches the shape of the first air duct 111 , which can facilitate the sealed connection between the second air duct 211 and the first air duct 111 , and can also facilitate the sealed connection between the ventilation pipe 11 and the end plate 21 .

[0124] Of course, in other embodiments, the projection shape of the second air duct 211 along the length direction x of the battery cell 10 may be different from the projection shape of the first air duct 111 along the length direction x of the battery cell 10 .

[0125] See also Figure 3 , Figure 4 In some embodiments of the present application, along the length direction x of the battery cell 10 , the projection shape of the first air duct 111 is waist-shaped.

[0126] By adopting the above solution, by making the projection shape of the first air duct 111 along the length direction x of the battery cell 10 be kidney-shaped, the heat dissipation area of the first air duct 111 can be enlarged, the contact area between the heat exchange air flow flowing in the first air duct 111 and each area of the battery cell 10 can be increased, so that the heat dissipation effect and heat dissipation efficiency of each area of the battery cell 10 can be improved, and the heat dissipation performance of the battery pack can be optimized and improved.

[0127] Of course, in other embodiments, the projection shape of the first air duct 111 along the length direction x of the battery cell 10 can be other shapes, such as circular.

[0128] Please refer to Figure 3 , Figure 4 , in some embodiments of the present application, the center line of the ventilation pipe fitting 11 coincides with the center line of the battery cell 10.

[0129] By adopting the above solution, by making the center line of the ventilation pipe fitting 11 coincide with the center line of the battery cell 10, the ventilation pipe fitting 11 can be centered at the exact center of the battery cell 10. Based on this, the ventilation pipe fitting 11 can be optimally arranged in the core area where the battery cell 10 generates more heat, which is convenient for the heat exchange air flow flowing in the first air duct 111 to directly and quickly take away the heat in the core area of the battery cell 10, and is convenient for the heat exchange air flow flowing in the first air duct 111 to diffuse circumferentially along the ventilation pipe fitting 11 and evenly take away the heat in the edge area of the battery cell 10, so that the distribution of heat inside the battery cell 10 can be balanced, the local overheating phenomenon of the battery cell 10 can be reduced, and the heat dissipation performance of the battery pack can be optimized and improved.

[0130] Of course, in other embodiments, the center line of the ventilation pipe fitting 11 and the center line of the battery cell 10 can be spaced apart.

[0131] Please refer to Figure 1 , some embodiments of the present application provide an electrical device, including the battery pack provided by the embodiments of the present application.

[0132] By adopting the above solution, the electrical device can optimize the performance, use reliability and use safety of the electrical device by applying the battery pack provided by the embodiments of the present application.

[0133] The battery pack disclosed in the embodiments of the present application can be used in electrical devices that use the battery pack as a power source, or in various energy storage systems that use the battery pack as an energy storage element. The electrical device can be, but is not limited to, a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, and an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or an extended-range electric vehicle, etc. The spacecraft includes an airplane, a rocket, a space shuttle, and a spaceship, etc. The electric toy includes a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and a railway electric tool, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, a hammer drill, an impact electric drill, a concrete vibrator, and a planer, etc.

[0134] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, or improvements made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A battery pack, characterized in that: include: The battery cell is provided with a ventilation pipe, the ventilation pipe is extended along the length direction of the battery cell, and the inner space of the ventilation pipe forms a first air duct penetrating the battery cell; The box body includes two end plates, which are respectively arranged at two opposite ends of the battery monomer along the length direction of the battery monomer, and the end plates are penetrated by a second air duct which is in one-to-one correspondence with the first air duct.

2. The battery pack according to claim 1, characterized in that: The end of the ventilation pipe is sealed and connected to the end plate.

3. The battery pack according to claim 2, characterized in that: The end surface of the ventilation pipe is abutted against and welded to the inner side surface of the end plate.

4. The battery pack according to claim 1, wherein: The battery cell comprises a housing, an electrode assembly and two electrode terminals; The housing comprises a shell and two end covers, the shell is extended along the length direction of the battery cell and is cylindrical, the two end covers are respectively mounted on opposite ends of the shell, and the end covers are penetrated with mounting holes; The electrode assembly is wound between the outer periphery of the ventilation pipe and the inner periphery of the shell; The polarities of the two electrode terminals are opposite, and the two electrode terminals are respectively penetrated and installed in the installation holes of the two end covers. The electrode terminals are electrically connected to the electrode assemblies arranged adjacent to them. The electrode terminals are penetrated by through holes, and the ventilation pipes are penetrated through the through holes of the two electrode terminals.

5. The battery pack according to claim 4, characterized in that: The battery cell includes a plurality of electrode assemblies, and the plurality of electrode assemblies are sequentially arranged along the length direction of the battery cell and sequentially connected in series.

6. The battery pack according to claim 4, characterized in that: The end of the ventilation pipe protrudes from the outer end surface of the electrode terminal.

7. The battery pack according to claim 4, characterized in that: A sealing member is provided between the mounting hole and the electrode terminal, and the sealing member seals a gap between the mounting hole and the electrode terminal.

8. The battery pack according to claim 7, characterized in that: The electrode terminal comprises a main body and a flange, wherein the main body is installed in the installation hole, and the flange is connected to the outer end of the main body and extends outward along the circumference of the main body; The sealing member surrounds the outer circumference of the main body, and the sealing member seals against the outer circumferential surface of the main body, and seals against the end surface of the flange portion facing the flange.

9. The battery pack according to claim 7, characterized in that: A portion of the end cap is embedded in the seal.

10. The battery pack according to claim 4, characterized in that: The battery cell includes an insulating film, which surrounds the outer circumference of the ventilation pipe. The opposite ends of the insulating film protrude from the outer end surfaces of the two electrode terminals respectively. The insulating film insulates and isolates the ventilation pipe from the electrode terminals and insulates and isolates the ventilation pipe from the electrode assembly.

11. The battery pack according to any one of claims 4 to 10, characterized in that: At least one end of the housing is provided with an explosion-proof valve, and the explosion-proof valve is provided on the peripheral side of the electrode terminal; And / or, at least one end of the shell is provided with a liquid injection hole, and the liquid injection hole is provided on the peripheral side of the electrode terminal.

12. The battery pack according to any one of claims 1 to 10, characterized in that: Along the length direction of the battery cell, the projection shape of the first air duct is the same as the projection shape of the battery cell; and / or, along the length direction of the battery cell, the projection shape of the second air duct is the same as the projection shape of the first air duct; And / or, along the length direction of the battery cell, the projection shape of the first air duct is waist-shaped.

13. The battery pack according to any one of claims 1 to 10, characterized in that: The center line of the ventilation pipe is arranged to coincide with the center line of the battery cell.

14. An electrical device, characterized in that: A battery pack comprising the battery pack as claimed in any one of claims 1 to 13.

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