Battery cell and battery pack

Abstract

The invention provides a battery monomer and a battery pack, and relates to the field of batteries. The battery monomer comprises at least two naked battery cells and a connecting piece with a liquid injection hole, the connecting piece is connected with two adjacent naked battery cells in the first direction; and the liquid injection hole is formed in the first end surface of the connecting piece in the second direction and is configured to inject liquid electrolyte into the two adjacent naked battery cells through the liquid injection hole. According to the battery monomer provided by the embodiment of the invention, only the battery monomer needs to be arranged in the first direction, and a cross beam and a longitudinal beam do not need to be arranged, so that the space utilization rate of a whole battery pack is improved, and the battery monomer is high in structural strength, high in quick charging capacity, simple in production process and high in manufacturability.

Description

Technical Field

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

[0002] Batteries are crucial in the field of new energy. They are the core components for storing and providing electrical energy, and directly affect the performance, endurance and reliability of electric vehicles, energy storage systems and other equipment. As a key carrier of clean energy, batteries can effectively store and smoothly output renewable energy (such as solar energy and wind energy), help reduce dependence on fossil fuels, and promote the transformation of energy structure towards sustainability.

[0003] With the development of battery technology, batteries tend to be longer and longer in order to improve space utilization and energy density. By lengthening the cells, they can be arranged more compactly in the battery pack, reducing the space occupied by structures such as brackets, thereby increasing battery capacity. In addition, long cells help simplify the battery system structure, reduce system complexity and cost, and improve endurance to meet the needs of new energy vehicles and other applications for efficient energy storage.

[0004] At present, two cells of medium length (500 to 650 mm) can be arranged in the Y direction of the battery pack, but due to the presence of horizontal and vertical beams, the space utilization is affected to a certain extent. In order to improve the space utilization, the length of the cell is extended (900 to 1300 mm), so that only one cell is required in the Y direction. However, cells that are too long increase the process difficulty in production, reduce the yield rate, and have poor manufacturability. At the same time, the fast charging capability is also weakened. Summary of the invention

[0005] In view of the above problems, the purpose of the embodiments of the present application is to provide a battery cell and a battery pack for

[0006] In a first aspect, an embodiment of the present application provides a battery cell, comprising: at least two bare cells and a connector having an injection hole; the connector connects two adjacent bare cells in a first direction; the injection hole is disposed on a first end surface of the connector in a second direction, and is configured to inject liquid electrolyte into the two adjacent bare cells through the injection hole.

[0007] In the above implementation process, the battery cell in this embodiment is firmly connected to the adjacent bare cells by setting a connector, and a liquid injection hole is set on the connector, which simplifies the injection process of the liquid electrolyte and optimizes the distribution efficiency of the electrolyte. It not only improves production efficiency and reduces process complexity, but also ensures that the electrolyte is evenly distributed in the battery cell, thereby improving the electrochemical performance and service life of the battery. In addition, since there is no need to set horizontal and vertical beams when the battery cell is packed, the space utilization rate is further improved. The structure has high strength, strong fast charging capability, simple production process, and high manufacturability.

[0008] Optionally, in an embodiment of the present application, the bare cell includes a first bare cell and a second bare cell that are adjacent to each other; the connecting member includes a first connecting side and a second connecting side along a first direction; the first connecting side is connected to the negative pole or the positive pole of the first bare cell; the second connecting side is connected to the positive pole of the second bare cell when the first connecting side is connected to the negative pole of the first bare cell; the second connecting side is connected to the positive pole of the second bare cell when the first connecting side is connected to the positive pole of the first bare cell.

[0009] In the above implementation process, the connector structure in this embodiment connects the positive and negative electrodes of two adjacent bare cells respectively through two connecting sides, thereby realizing a stable series connection between the cells and ensuring smooth current conduction. This structure simplifies the circuit design inside the battery pack, reduces the complexity of the connector, and provides a flexible installation method. In addition, the connector structure is simple and easy to manufacture, which is conducive to improving production efficiency.

[0010] Optionally, in an embodiment of the present application, the connecting member includes a first cover body, a second cover body and an intermediate connecting part; the first cover body is arranged on the first connection side and connected to the first side of the intermediate connecting part, and the first cover body is configured to protect the connection area between the first bare battery cell and the intermediate connecting part; the second cover body is arranged on the second connection side and connected to the second side of the intermediate connecting part, and the second cover body is configured to protect the connection area between the second bare battery cell and the intermediate connecting part.

[0011] In the above implementation process, this embodiment effectively protects the connection area between the bare battery cell and the intermediate connection part by setting the first cover body and the second cover body, prevents external mechanical damage or environmental factors, and ensures the long-term reliability of the connection. The intermediate connection part provides a stable electrical connection path and improves the stability of current conduction. The overall structural design is simple and effective, which not only improves the mechanical strength and electrical stability of the connector, but also makes the production and maintenance of the battery more convenient.

[0012] Optionally, in an embodiment of the present application, the battery cell also includes a first shell and a second shell; the first shell is sleeved on the outside of the first bare battery cell, and the second shell is sleeved on the outside of the second bare battery cell; the first end of the first shell is connected to the second end of the first cover body, and the second end of the second shell is connected to the first end of the second cover body.

[0013] In the above implementation process, the battery cell in this embodiment provides additional mechanical protection for the bare battery cell by setting the first shell and the second shell to prevent damage to the battery cell caused by external environmental factors (such as impact and vibration). At the same time, the connection between the shell and the cover ensures the stable packaging of the battery cell and the connector, and improves the overall structural strength and stability of the battery.

[0014] Optionally, in an embodiment of the present application, the first cover body and the second cover body both include a first sub-cover body and a second sub-cover body; the first sub-cover body is arranged outside the second sub-cover body; the edge of the first sub-cover body is provided with a connecting edge protruding from the plane of the first sub-cover body.

[0015] In the above implementation process, this embodiment realizes a more stable battery packaging structure by making the first cover and the second cover both consist of the first sub-cover and the second sub-cover, and setting a stepped connection edge at the edge of the first sub-cover. The first sub-cover acts as an external protective layer, providing additional mechanical strength, and the second sub-cover ensures a stable electrical connection between the battery cell and the connecting component. The setting of the connection edge can ensure the tightness and mechanical strength of the package.

[0016] Optionally, in an embodiment of the present application, the intermediate connecting portion includes: an insulating layer, a first connecting piece having a first part and a second part, a second connecting piece and a substrate; the second part of the substrate protrudes from the first surface of the first part of the substrate, the thickness direction of the second part of the substrate is perpendicular to the thickness direction of the substrate counter part, and the first part of the substrate exceeds both sides of the thickness direction of the second part of the substrate; the thickness direction of the first part of the first connecting piece is perpendicular to the thickness direction of the second part of the first connecting piece, and the first part of the first connecting piece exceeds the first side of the thickness direction of the second part of the first connecting piece; the first part of the first connecting piece contacts the first surface of the first part of the substrate, and the second part of the first connecting piece contacts the first surface of the second part of the substrate; the thickness direction of the first part of the second connecting piece is perpendicular to the thickness direction of the second part of the second connecting piece, and the first part of the second connecting piece exceeds the second side of the thickness direction of the second part of the second connecting piece; the first part of the second connecting piece contacts the first surface of the first part of the substrate, and the second part of the second connecting piece contacts the second surface of the second part of the substrate; the insulating layer is arranged between the first connecting portion and the substrate, and between the second connecting portion and the substrate.

[0017] In the above implementation process, the intermediate connection part in this embodiment combines the insulating layer, the connecting piece and the substrate to achieve effective electrical connection and good electrical isolation between the battery cells. The protruding part of the substrate provides a stable support for the connecting piece, and the precise layout of the connecting piece ensures the smooth conduction of current. The insulating layer provides the necessary electrical safety for the entire connection part, avoids the risk of short circuit, and improves the overall safety and stability of the battery.

[0018] Optionally, in an embodiment of the present application, the intermediate connecting portion further includes a composite pole and a sealing ring; the second portion of the first connecting piece, the second portion of the second connecting piece and the second portion of the substrate are provided with through holes whose positions overlap; the composite pole passes through the through hole to connect the first connecting piece and the second connecting piece; the sealing ring is sleeved on the insulating layer of the first connection side and the second connection side of the composite pole.

[0019] In the above implementation process, the embodiment of the present application connects the first connecting plate and the second connecting plate by setting a composite pole passing through the through hole of the first connecting plate, the second connecting plate and the substrate, thereby ensuring the electrical connection between the first battery cell and the second battery cell. The sealing ring provides tight sealing protection on the outside of the composite pole, further preventing external moisture, dust or other contaminants from entering the electrical connection part, reducing the risk of short circuit and leakage.

[0020] Optionally, in an embodiment of the present application, the first connecting plate and the second connecting plate are respectively one of a first conductive material and a second conductive material; the material of the first connecting side of the composite pole is consistent with the first connecting plate, and the material of the second connecting side of the composite pole is consistent with the second connecting plate.

[0021] In the above implementation process, by using different conductive materials in the design of the first connecting piece, the second connecting piece and the composite pole, and ensuring that the materials at both ends of the composite pole are consistent with the corresponding connecting pieces, the matching and conductive performance of the electrical connection are significantly improved.

[0022] Optionally, in an embodiment of the present application, the battery cell further includes an end cover having an explosion-proof valve; the end cover is disposed at both ends of the battery cell; and the explosion-proof valve is configured to pass gas.

[0023] In the above implementation process, the embodiment of the present application can effectively improve the safety of the battery by setting an explosion-proof valve on the end cap of the battery cell. When the battery is faulty or causes internal gas accumulation, the explosion-proof valve will automatically open and quickly release the excess gas to avoid the risk of battery rupture or explosion caused by overpressure.

[0024] In a second aspect, an embodiment of the present application provides a battery pack, comprising: a pack body and a battery cell; a plurality of battery cells are stacked in the pack body along a third direction; wherein the battery cell comprises the battery cell as in the first aspect of the present application.

[0025] In the above implementation process, the battery pack provided by the present application is based on the battery cell proposed in the embodiment of the present application, and adopts a compact design without horizontal and vertical beams. The space utilization rate inside the battery pack is greatly improved, the gap between the battery cell and the side walls around the pack body is reduced, and the internal layout is optimized. Not only the capacity of the battery pack is improved, the energy density of the battery is increased, but also the overall strength of the battery pack is significantly improved by reducing redundant structural parts, and its durability and stability are enhanced. At the same time, the compact structural layout also reduces the overall weight and improves the practicality of the battery pack in various application scenarios.

[0026] In order to make the above-mentioned objects, features and advantages of the present application more obvious and understandable, embodiments are given below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 An exploded diagram of a battery cell structure provided in an embodiment of the present application;

[0029] Figure 2 A schematic diagram of the structure of a connector provided in an embodiment of the present application;

[0030] Figure 3 An exploded diagram of the connector structure provided in an embodiment of the present application;

[0031] Figure 4 A top view and a BB cross-sectional view of a connector provided in an embodiment of the present application;

[0032] Figure 5 A schematic diagram of welding the intermediate connection portion and the bare battery cell provided in an embodiment of the present application;

[0033] Figure 6 An exploded view of another battery cell structure provided in an embodiment of the present application;

[0034] Figure 7 An exploded view of the structure of the intermediate connection portion provided in an embodiment of the present application;

[0035] Figure 8 A schematic diagram of the structure of the battery pack provided for the implementation of this application;

[0036] Fig. 9 A manufacturing flow chart of a battery cell provided in an embodiment of the present application;

[0037] Figure numerals: battery cell-1000; bare cell-100; first bare cell-110; second bare cell-120; connector-200; first end surface-210; injection hole-211; first connection side-A; second connection side-B; first cover-220; second end connection of the first cover-221; second cover-230; first end connection of the second cover-231; middle connection part-240; first sub-cover-a; second sub-cover-b; connection edge-a1; insulating layer-241; first connecting piece-242; second connecting piece-243; substrate -244; composite pole-245; sealing ring-246; through hole-247; first part of the first connecting plate-242a; second part of the first connecting plate-242b; first part of the second connecting plate-243a; second part of the second connecting plate-243b; first part of the substrate-244a; first surface of the first part of the substrate-244a1; second part of the substrate-244b; first shell-310; second shell-320; first end of the first shell-311; second end of the second shell-321; end cover-400; explosion-proof valve-410. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0041] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0042] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0043] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] Batteries are crucial in the field of new energy. They are the core of storing and releasing electrical energy, affecting the performance and endurance of electric vehicles and energy storage systems. Batteries can not only effectively store renewable energy, but also output it smoothly, reduce dependence on fossil fuels, and promote the transformation of energy structure towards sustainability. Therefore, the development of battery technology is crucial to the popularization of new energy and the reduction of carbon emissions.

[0045] In order to improve the space utilization of the whole pack, the design of batteries is moving towards longer and longer cells. The increase in cell length can make more efficient use of the limited space in the battery pack, thereby increasing energy density. The main driving force behind this trend is the increasing requirements for battery capacity and endurance in the new energy field, especially electric vehicles. By lengthening the cell, more battery materials can be placed in the limited space of the vehicle body, thereby increasing energy storage and improving the range of the vehicle.

[0046] When the cell length is between 500 and 650 mm, the battery pack design allows two cells to be arranged in the Y direction. This design can provide higher energy storage without significantly increasing the length of a single cell. However, the battery pack usually requires crossbeams and longitudinal beams to support the structure, which occupies a certain amount of space, resulting in a decrease in the effective space utilization in the Y direction.

[0047] The existing technology also extends a single battery cell to 900 to 1300 mm, so that only one battery cell needs to be placed in the Y-direction layout. By reducing the number of battery cells and reducing the dependence on the horizontal and vertical beam structures, the space utilization rate can be further improved and the total energy of the battery pack can be increased. However, long batteries face problems such as difficult production processes, low production yields, poor manufacturability, and weak fast charging capabilities.

[0048] The manufacturing of long cells requires higher precision and control. In key processes such as coating, winding and packaging, the longer the cell, the more likely it is to deform and have uneven thickness, which increases the difficulty of production. Material processing, exhaust, packaging, etc. of long cells all require new equipment and technical support.

[0049] Long cells are more prone to quality defects during the production process, such as uneven distribution of internal materials and large differences in coating thickness, which leads to poor product consistency and ultimately affects production yield. Even the slightest error in the manufacturing process will cause the entire cell to fail, wasting materials and man-hours.

[0050] Longer cells require more sophisticated equipment and production lines, and existing equipment may need to be adjusted on a large scale to accommodate new size specifications. In addition, the assembly, transportation and installation of long cells also face greater challenges. During the manufacturing process, the handling and processing of cells is more complicated, increasing production costs and difficulties.

[0051] The current path of a long cell is longer than that of a short cell, which increases the internal resistance and limits the fast charging capability of the cell. During fast charging, the current distribution in the cell is prone to unevenness, causing overheating or overcharging in some areas, affecting the charging speed and safety of the cell. Therefore, although long cells can increase the energy density of the battery pack, they sacrifice charging speed and efficiency, making it difficult to take into account fast charging performance.

[0052] Based on this, the embodiment of the present application provides a battery cell and a battery pack, wherein the battery cell is composed of two medium-length bare cells connected in series, with a connector in the middle. The overall design does not require the installation of a horizontal and vertical beam between the two bare cells, and the space utilization of the entire pack in the length direction of the cells is improved; and the structure has high strength, strong fast charging capability, simple production process, and high manufacturability.

[0053] Please see Figure 1 , Figure 1This is an exploded view of the battery cell structure provided in an embodiment of the present application; the battery cell 1000 provided in an embodiment of the present application includes at least two bare battery cells 100 and a connector 200 having a liquid injection hole 211.

[0054] The connector 200 connects two adjacent bare cells 100 in a first direction.

[0055] The injection hole 211 is disposed on the first end surface 210 of the connector 200 in the second direction, and is configured to inject liquid electrolyte into two adjacent bare cells 100 through the injection hole 211 .

[0056] like Figure 1 As shown, in the embodiment of the present application, the first direction is the length direction of the battery cell (Y direction), the third direction is the thickness direction of the battery cell (X direction), and the second direction is the direction perpendicular to the plane where the length direction and the thickness direction are located (Z direction).

[0057] The connector 200 is a component used to connect two adjacent bare cells 100 together, and plays a role of physical fixation and electrical connection. In a first direction, the connector 200 tightly connects two adjacent bare cells.

[0058] The injection hole 211 is disposed on the first end surface 210 of the connecting member 200 in the third direction. Figure 1 As shown, two injection holes 211 are provided on the first end surface 210, and liquid electrolyte can be injected into two adjacent bare cells 100 at the same time. Optionally, the injection hole 211 can be set to a circular, elliptical or other geometric shape, depending on the injection requirements of the electrolyte. The injection hole 211 can be set to be single or multiple, ensuring that the liquid electrolyte can be quickly and evenly distributed to various parts of the two adjacent bare cells 100. The battery cell 1000 provided in the embodiment of the present application sets the injection hole 211 on the connector 200 between the two bare cells 100, which can simplify the injection operation of the electrolyte, realize the simultaneous injection of two cells, and improve production efficiency.

[0059] It should be noted that the bare cells 100 with a length between 500 and 650 mm are used in the embodiments of the present application. The connection of two bare cells 100 through a connector 200 to form a battery cell 1000 is only exemplary. The length of the battery cell composed of two bare cells 100 is between 900 and 1300 mm, the height is between 70 and 140 mm, and the thickness is between 12 and 36 mm. In some possible embodiments, in order to increase the length of the battery in one step, the number of bare cells 100 can be increased, and adjacent bare cells 100 are connected using connectors 200.

[0060] pass Figure 1It can be seen that the battery cell 1000 in this embodiment is firmly connected to the adjacent bare battery cells 100 by providing a connector 200, and an injection hole 211 is provided on the connector 200. There is no need to rotate or flip the battery cell during injection, which simplifies the injection process of the liquid electrolyte and optimizes the distribution efficiency of the electrolyte. It not only improves production efficiency and reduces process complexity, but also ensures that the electrolyte is evenly distributed in the battery cell, thereby improving the electrochemical performance and service life of the battery. In addition, since there is no need to set horizontal and vertical beams when the battery cell 1000 is packed, the space utilization is further improved. The structure has high strength, strong fast charging capability, simple production process, and high manufacturability.

[0061] Please see Figure 2 , Figure 2 A schematic diagram of the structure of the connector provided in the embodiment of the present application; in an optional embodiment, taking two adjacent bare cells 100 constituting a single cell as an example, the structure of the connector 200 in the embodiment of the present application is described, assuming that the two adjacent bare cells 100 are the first bare cell and the second bare cell respectively. The connector 200 includes a first connection side A and a second connection side B along a first direction.

[0062] The first connection side A is connected to the negative electrode or the positive electrode of the first bare battery cell.

[0063] The second connection side B is connected to the positive electrode of the second bare cell when the first connection side A is connected to the negative electrode of the first bare cell. The second connection side B is connected to the positive electrode of the second bare cell when the first connection side A is connected to the positive electrode of the first bare cell.

[0064] The first connection side A of the connector 200 is connected to the tab of the first bare cell along the first direction of the battery, and the connection position can be the positive or negative pole of the first bare cell. When the first connection side A is connected to the negative pole of the first bare cell, the second connection side B is connected to the positive pole of the second bare cell. Conversely, if the first connection side A is connected to the positive pole of the first bare cell, the second connection side B is connected to the negative pole of the second bare cell. This part is responsible for electrically connecting the two bare cells in series to achieve smooth conduction of current.

[0065] pass Figure 2 It can be seen that the connector 200 structure in this embodiment connects the positive and negative electrodes of two adjacent bare cells 100 through two connecting sides, thereby achieving a stable series connection between the cells and ensuring smooth current conduction. This structure simplifies the circuit design inside the battery pack, reduces the complexity of the connector 200, and provides a flexible installation method. In addition, the connector 200 has a simple structure and is easy to manufacture, which is conducive to improving production efficiency.

[0066] Please see Figure 3 , Figure 3An exploded view of the connector structure provided in an embodiment of the present application; in an optional embodiment, the connector 200 includes a first cover body 220, a second cover body 230 and an intermediate connecting portion 240.

[0067] The first cover 220 is disposed at the first connection side A and connected to the first side of the middle connection part 240 . The first cover 220 is configured to protect the connection area between the first bare cell and the middle connection part 240 .

[0068] The second cover 230 is disposed at the second connection side B and connected to the second side of the middle connection part 240 . The second cover 230 is configured to protect the connection area between the second bare cell and the middle connection part 240 .

[0069] The first cover 220 is located at the first connection side A of the connector 200 and is connected to the first side of the intermediate connection part 240. Its main function is to cover and protect the connection area between the first bare cell and the intermediate connection part 240, prevent the area from being disturbed or damaged by the external environment, such as mechanical pressure or moisture intrusion, and ensure stable and reliable connection.

[0070] The second cover 230 is disposed on the second connection side B of the connector 200 and is connected to the second side of the intermediate connection part 240. Its function is similar to that of the first cover 220, mainly to protect the connection area between the second bare cell and the intermediate connection part 240, to ensure the safety and long-term stability of the connection, and to avoid failure or poor contact of the connection part.

[0071] The middle connecting part 240 is the core part of the connector 200, connecting the first cover 220 and the second cover 230, and realizing the electrical connection between the two bare cells. This part plays the role of electrically connecting the two bare cells, ensuring that the current can smoothly pass through the channel between the cells, and at the same time provides mechanical support to ensure the stability of the connector 200 during use.

[0072] pass Figure 3 It can be seen that this embodiment effectively protects the connection area between the bare battery cell and the intermediate connection part 240 by providing the first cover body 220 and the second cover body 230, prevents external mechanical damage or environmental factors, and ensures the long-term reliability of the connection. The intermediate connection part 240 provides a stable electrical connection path and improves the stability of current conduction. The overall structural design is simple and effective, which not only improves the mechanical strength and electrical stability of the connector 200, but also makes the production and maintenance of the battery more convenient.

[0073] Please see Figure 5 , Figure 5 Another exploded view of a battery cell structure provided in an embodiment of the present application; in an optional embodiment, the battery cell 1000 further includes a first shell 310 and a second shell 320 .

[0074] The first shell 310 is sleeved on the outside of the first bare cell 110, and the second shell 320 is sleeved on the outside of the second bare cell 110. The first end 311 of the first shell is connected to the second end 221 of the first cover, and the second end 321 of the second shell is connected to the first end 231 of the second cover.

[0075] In the above implementation process, the first shell 310 is sleeved on the outside of the first bare battery cell 110, and its function is to provide mechanical protection for the first bare battery cell 110 to prevent damage to the battery cell due to external impact, vibration or environmental factors. The first end 311 of the first shell is connected to the second end of the first cover body 220 to ensure that the battery cell and the cover body are tightly packaged, further improving the structural strength and stability of the battery. The second shell 320 is also sleeved on the outside of the second bare battery cell 110 to protect the second bare battery cell 110 from physical damage. The second connection end of the second shell 320 is connected 231 to the first end of the second cover body to ensure that the second bare battery cell 110 is firmly packaged and tightly matched with the structure of the connector 200.

[0076] It should be noted that in the embodiment of the present application, the material of the first shell 310 and the second shell 320 can be aluminum; a composite material can also be used, for example, a metal shell is used on the outer layer to enhance protection, and an insulating material is used inside to provide electrical isolation.

[0077] pass Figure 5 It can be seen that the battery cell 1000 in this embodiment provides additional mechanical protection for the bare battery cell by providing the first shell 310 and the second shell 320 to prevent damage to the battery cell caused by external environmental factors (such as impact and vibration). At the same time, the connection between the shell and the cover ensures the stable packaging of the battery cell and the connector 200, thereby improving the overall structural strength and stability of the battery.

[0078] Please Figure 3 See on the basis of Figure 4 and Figure 5 , Figure 4 A top view and a BB cross-sectional view of a connector provided in an embodiment of the present application; Figure 5 A schematic diagram of welding the intermediate connection part and the bare cell provided in an embodiment of the present application; in an optional embodiment, the first cover body 220 and the second cover body 230 both include a first sub-cover body a and a second sub-cover body b.

[0079] The first sub-cover body a is arranged outside the second sub-cover body b. The edge of the first sub-cover body a is provided with a connecting edge a1 protruding from the plane of the first sub-cover body a.

[0080] In the above implementation process, the first sub-cover a is located on the outside of the second sub-cover b, and its main function is to serve as an external protective layer, provide additional mechanical strength, and protect the internal structure. It can be made of a relatively strong material to withstand the impact and pressure of the external environment. The second sub-cover b is located on the inner side of the first sub-cover a, close to the connection part of the battery cell, and its main function is to ensure that the electrical connection between the battery cell and the connector 200 is not interfered by the outside world by providing precise packaging, for example, a plastic cover.

[0081] The edge of the first sub-cover a is designed with a connecting edge a1, which may be in a step-shaped or other protruding form, so as to facilitate welding or other forms of mechanical connection during the assembly process. Figure 5 As shown, the tabs of the first bare cell 110 and the second bare cell 120 can be welded simultaneously to the copper connecting piece and the aluminum connecting piece of the middle connecting part 240, respectively, so as to further improve the welding efficiency. Finally, a stable connection can be formed between the middle connecting part 240 and the first cover body 220 and the second cover body 230, thereby ensuring the airtightness and mechanical strength of the package and preventing liquid, electrical or mechanical interference.

[0082] It can be seen that in this embodiment, a more stable battery packaging structure is achieved by forming the first cover 220 and the second cover 230 both by the first sub-cover a and the second sub-cover b, and providing a stepped connection edge a1 on the edge of the first sub-cover a. The first sub-cover a acts as an external protective layer, providing additional mechanical strength, and the second sub-cover b ensures a stable electrical connection between the battery cell and the connecting component. The setting of the connection edge a1 can ensure the tightness and mechanical strength of the package.

[0083] Please see Figure 7 , Figure 7 An exploded view of the structure of the intermediate connection part provided in an embodiment of the present application; in an optional embodiment, the intermediate connection part 240 includes: an insulating layer 241, a first connection piece 242 having a first part and a second part, a second connection piece 243 and a substrate 244.

[0084] The second portion 244b of the substrate protrudes from the first surface 244a1 of the first portion of the substrate, the thickness direction of the second portion 244b of the substrate is perpendicular to the thickness direction of the substrate 244a, and the first portion 244a of the substrate exceeds both sides of the thickness direction of the second portion 244b of the substrate.

[0085] The thickness direction of the first part 242a of the first connecting piece is perpendicular to the thickness direction of the second part 242b of the first connecting piece, and the first part 242a of the first connecting piece exceeds the first side of the thickness direction of the second part 242b of the first connecting piece; the first part 242a of the first connecting piece contacts the first surface 244a1 of the first part of the substrate, and the second part 242b of the first connecting piece contacts the first surface of the second part 244b of the substrate.

[0086] The thickness direction of the first part 243a of the second connecting piece is perpendicular to the thickness direction of the second part 243b of the second connecting piece, and the first part 243a of the second connecting piece exceeds the second side of the thickness direction of the second part 243b of the second connecting piece; the first part 243a of the second connecting piece contacts the first surface 244a1 of the first part of the substrate, and the second part 243b of the second connecting piece contacts the second surface of the second part 244b of the substrate.

[0087] The insulating layer 241 is disposed between the first connection portion and the substrate 244 , and between the second connection portion and the substrate 244 .

[0088] In the above structure, the substrate 244 is the core part of the intermediate connecting part 240, the second part 244b of the substrate protrudes from the first surface 244a1 of the first part of the substrate, and its thickness direction is perpendicular to the thickness direction of the first part 244a of the substrate; the first part 244a of the substrate exceeds the second part 244b of the substrate on both sides in the thickness direction, thereby increasing the overall strength of the structure. Figure 5 The T-shaped structure shown.

[0089] The thickness direction of the first portion 242a of the first connecting piece is perpendicular to the thickness direction of the second portion 242b of the first connecting piece, and the first portion exceeds one side of the second portion, forming a Figure 5 The reverse L-shaped structure shown in FIG. 2 is a structure in which the thickness direction of the first portion 243a of the second connecting piece is perpendicular to the thickness direction of the second portion 243b of the second connecting piece, and the first portion exceeds the other side of the second portion, forming a structure as shown in FIG. Figure 7 The first part 242a of the first connecting piece contacts the first surface 244a1 of the first part of the substrate, and the second part contacts the first surface of the second part 244b of the substrate; the first part 243a of the second connecting piece contacts the first surface 244a1 of the first part of the substrate, and the second part contacts the second surface of the second part 244b of the substrate, thereby ensuring the reliability of the electrical connection and realizing the conduction of the current.

[0090] The insulating layer 241 is disposed between the first connection piece 242 and the substrate 244 , and between the second connection piece 243 and the substrate 244 , to prevent electrical short circuits and ensure connection safety.

[0091] pass Figure 7 It can be seen that the intermediate connection part 240 in this embodiment combines the insulating layer 241, the connecting piece and the substrate 244 to achieve effective electrical connection and good electrical isolation between the battery cells. The protruding part of the substrate 244 provides a stable support for the connecting piece, and the precise layout of the connecting piece ensures the smooth conduction of current. The insulating layer 241 provides the necessary electrical safety for the entire connection part, avoids the risk of short circuit, and improves the overall safety and stability of the battery.

[0092] Please continue to see Figure 7 In an optional embodiment, the intermediate connecting portion 240 further includes a composite pole 245 and a sealing ring 246. The second portion 242b of the first connecting piece, the second portion 243b of the second connecting piece and the second portion 244b of the base plate are provided with through holes 247 whose positions overlap.

[0093] The composite pole 245 passes through the through hole 247 to connect the first connecting piece 242 and the second connecting piece 243 .

[0094] In the above implementation process, the composite pole 245 is a key component for connecting the first connecting piece 242 and the second connecting piece 243. Figure 7 As shown, two composite poles 245 are provided, which respectively pass through the through holes 247 which are arranged at the same position on the second part 242b of the first connecting plate, the second part 243b of the second connecting plate and the second part 244b of the substrate, and the composite poles 245 ensure the smooth conduction of current between the first connecting plate 242 and the second connecting plate 243.

[0095] The sealing ring 246 is sleeved on the composite pole 245 at the first connection side A and the second connection side B of the insulating layer 241 .

[0096] In the above implementation process, the sealing ring 246 is sleeved on the outside of the composite pole 245, and is respectively located in the insulating layer 241 of the first connection side A and the second connection side B. The sealing ring 246 provides an effective seal for the composite pole 245 and the through hole 247 to prevent the external environment (such as air, moisture or liquid) from entering the connection part, causing an electrical short circuit or other faults. At the same time, the sealing ring 246 enhances the sealing and safety of the connection structure, ensuring the stability of the battery in various use environments.

[0097] It can be seen that the embodiment of the present application connects the first connecting piece 242 and the second connecting piece 243 by setting a composite pole 245 that passes through the first connecting piece 242, the second connecting piece 243 and the through hole 247 of the substrate 244, thereby ensuring the electrical connection between the first battery cell and the second battery cell. The sealing ring 246 provides tight sealing protection on the outside of the composite pole 245, further preventing external moisture, dust or other contaminants from entering the electrical connection part, reducing the risk of short circuit and leakage.

[0098] In an optional embodiment, the first connecting piece 242 and the second connecting piece 243 are respectively made of one of a first conductive material and a second conductive material.

[0099] The material of the first connection side A of the composite pole 245 is consistent with that of the first connection piece 242 , and the material of the second connection side B of the composite pole 245 is consistent with that of the second connection piece 243 .

[0100] The first conductive material can be copper, aluminum or other highly conductive metal materials, and the second conductive material is different from the first conductive material. The first connection side A of the composite pole 245 adopts the same first conductive material as the first connecting piece 242 to ensure the conductivity consistency and current conduction efficiency when in contact with the first connecting piece 242. The second connection side B of the composite pole 245 adopts the same second conductive material as the second connecting piece 243, thereby matching with the second connecting piece 243. Exemplarily, if the material of the first connecting piece 242 is copper, the material of the first connection side A of the composite pole 245 is also copper; if the material of the second connecting piece 243 is aluminum, the material of the second connection side B of the composite pole 245 is also aluminum. It should be noted that the connection between the first connection side A of the composite pole 245 and the second connection side B of the composite pole 245 can be riveted or laser welded.

[0101] It can be seen that by using different conductive materials in the design of the first connecting piece 242, the second connecting piece 243 and the composite pole 245, and ensuring that the materials at both ends of the composite pole 245 are consistent with the corresponding connecting pieces, the matching and conductive performance of the electrical connection are significantly improved.

[0102] Please continue to see Figure 6 The battery cell 1000 further includes an end cover 400 having an explosion-proof valve 410 .

[0103] The end caps 400 are disposed at both ends of the battery cell 1000. The explosion-proof valve 410 is configured to pass gas.

[0104] The explosion-proof valve 410 is provided on the end cap 400 and automatically opens to release excess gas when excessive pressure is generated inside the battery. It plays a role in preventing the danger caused by excessive pressure inside the battery; when gas accumulates due to battery failure or overcharging, the explosion-proof valve 410 can reduce the pressure by discharging the gas, thereby preventing the battery from exploding or other dangerous situations.

[0105] It can be seen that the embodiment of the present application can effectively improve the safety of the battery by providing an explosion-proof valve 410 on the end cap 400 of the battery cell 1000. When the battery is faulty or has external causes that cause internal gas accumulation, the explosion-proof valve 410 will automatically open to quickly release excess gas, thereby avoiding the risk of battery rupture or explosion caused by overpressure.

[0106] Please see Figure 8 , Figure 8 A schematic diagram of the structure of a battery pack provided for the implementation of the present application; The present application provides a battery pack, the battery pack comprising: a pack body and a battery cell 1000.

[0107] The plurality of battery cells 1000 are arranged along the third direction ( Figure 6 The battery cells 1000 are stacked in the package in the X direction; wherein the battery cells 1000 are the above-mentioned battery cells 1000.

[0108] pass Figure 8 It can be seen that the battery pack provided by the present application is based on the battery cell 1000 proposed in the embodiment of the present application, and adopts a compact design without horizontal and vertical beams. The space utilization inside the battery pack is greatly improved, the gap between the battery cell and the side walls around the pack body is reduced, and the internal layout is optimized. Not only the capacity of the battery pack is improved, the energy density of the battery is increased, but also the overall strength of the battery pack is significantly improved by reducing redundant structural parts, and its durability and stability are enhanced. At the same time, the compact structural layout also reduces the overall weight and improves the practicality of the battery pack in various application scenarios.

[0109] This application also provides a method for manufacturing a battery cell, see Fig. 9 , Fig. 9 A manufacturing flow chart of a battery cell provided in an embodiment of the present application; the manufacturing method of the battery cell includes:

[0110] Step S1: provide an intermediate link, a first bare cell and a second bare cell, connect the copper tab of the first bare cell and the first connecting piece made of copper of the intermediate connection, and connect the aluminum tab of the second bare cell and the second connecting piece made of aluminum of the intermediate connection.

[0111] Step S2: providing a first cover body and a second cover body, respectively covering the middle connecting part with the second sub-cover body, and then respectively replacing the first sub-cover body on the second sub-cover body.

[0112] Step S3: provide a protection bracket 1 and a protection bracket 2, and respectively put the other ends of the first bare battery cell and the second bare battery cell through the protection brackets, and then wrap and fix them with insulating mylar.

[0113] Step S4: providing an aluminum shell 1 and an aluminum shell 2, and respectively sleeve the aluminum shell 1 and the aluminum shell 2 outside the first bare battery cell and outside the second bare battery cell.

[0114] Step S5: providing end caps 1 and 2, and welding aluminum shells 1 and 2 to end caps 1 and 2 respectively to form a closed whole with two battery cells connected in series.

[0115] Step S6: injecting liquid into the bare battery cell through the injection hole provided on the connecting piece.

[0116] In summary, the embodiment of the present application forms a single battery by connecting at least two bare cells 100 through a connector 200, providing a liquid injection hole 211 on the connector 200, using connecting plates and composite poles 245 made of different conductive materials, and compactly stacking multiple battery cells 1000 in the package, thereby improving the space utilization and structural strength of the battery pack as a whole. The introduction of the explosion-proof valve 410 enhances safety, ensures the effective release of gas under high pressure conditions, and prevents potential dangers. In addition, the elimination of the traditional crossbeam and longitudinal beam structure reduces the number of components, further improving the energy density and production efficiency of the battery pack, and ensuring that the battery has better safety and stability while maintaining high performance and long life.

[0117] The above are only embodiments of the present application and are not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: The battery cell comprises: at least two bare cells and a connector having a liquid injection hole; The connecting member connects two adjacent bare cells in a first direction; The injection hole is disposed on a first end surface of the connector in the second direction, and is configured to inject liquid electrolyte into two adjacent bare cells through the injection hole.

2. The battery cell according to claim 1, characterized in that: The bare battery cell comprises a first bare battery cell and a second bare battery cell adjacent to each other; the connecting member comprises a first connecting side and a second connecting side along the first direction; The first connection side is connected to the negative electrode or the positive electrode of the first bare battery cell; The second connection side is connected to the positive electrode of the second bare cell when the first connection side is connected to the negative electrode of the first bare cell; The second connection side is connected to the positive electrode of the second bare cell when the first connection side is connected to the positive electrode of the first bare cell.

3. The battery cell according to claim 2, characterized in that: The connecting member comprises a first cover body, a second cover body and an intermediate connecting portion; The first cover is disposed on the first connection side and connected to the first side of the middle connection portion, and the first cover is configured to protect the connection area between the first bare cell and the middle connection portion; The second cover is disposed on the second connection side and connected to the second side of the middle connection portion, and the second cover is configured to protect a connection area between the second bare cell and the middle connection portion.

4. The battery cell according to claim 3, characterized in that: The battery cell further includes a first shell and a second shell; The first shell is sleeved on the outside of the first bare battery core, and the second shell is sleeved on the outside of the second bare battery core; The first end of the first shell is connected to the second end of the first cover, and the second end of the second shell is connected to the first end of the second cover.

5. The battery cell according to claim 4, characterized in that: The first cover body and the second cover body each include a first sub-cover body and a second sub-cover body; The first sub-cover body is arranged outside the second sub-cover body; The edge of the first sub-cover body is provided with a connecting edge protruding from the plane of the first sub-cover body.

6. The battery cell according to claim 3, characterized in that: The intermediate connecting part comprises: an insulating layer, a first connecting piece having a first part and a second part, a second connecting piece and a substrate; The second portion of the substrate protrudes from the first surface of the first portion of the substrate, the thickness direction of the second portion of the substrate is perpendicular to the thickness direction of the substrate pair, and the first portion of the substrate exceeds both sides of the second portion of the substrate in the thickness direction; The thickness direction of the first portion of the first connecting sheet is perpendicular to the thickness direction of the second portion of the first connecting sheet, and the first portion of the first connecting sheet exceeds a first side of the thickness direction of the second portion of the first connecting sheet; the first portion of the first connecting sheet contacts the first surface of the first portion of the substrate, and the second portion of the first connecting sheet contacts the first surface of the second portion of the substrate; The thickness direction of the first part of the second connecting piece is perpendicular to the thickness direction of the second part of the second connecting piece, and the first part of the second connecting piece exceeds the second side of the thickness direction of the second part of the second connecting piece; the first part of the second connecting piece contacts the first surface of the first part of the substrate, and the second part of the second connecting piece contacts the second surface of the second part of the substrate; The insulating layer is disposed between the first connection portion and the substrate, and between the second connection portion and the substrate.

7. The battery cell according to claim 6, characterized in that: The intermediate connecting portion further comprises a composite pole and a sealing ring; the second portion of the first connecting piece, the second portion of the second connecting piece and the second portion of the substrate are provided with through holes that overlap in position; The composite pole passes through the through hole and connects the first connecting piece and the second connecting piece; The insulating layer of the sealing ring at the first connection side and the second connection side is sleeved on the composite pole.

8. The battery cell according to claim 7, characterized in that: The first connecting sheet and the second connecting sheet are respectively made of one of a first conductive material and a second conductive material; The material of the first connection side of the composite pole is consistent with that of the first connection piece, and the material of the second connection side of the composite pole is consistent with that of the second connection piece.

9. The battery cell according to claim 1, characterized in that: The battery cell also includes an end cap having an explosion-proof valve; The end caps are arranged at both ends of the battery cell; and the explosion-proof valve is configured to pass gas.

10. A battery pack, characterized in that: The battery pack comprises: a pack body and a battery cell; A plurality of the battery cells are stacked in the package along a third direction; wherein the battery cells include the battery cells according to any one of claims 1 to 8.

Images