Battery cell, battery device, and electric device

Abstract

The utility model discloses a battery monomer, battery device and electric device, the battery monomer includes: casing, support structure and electrode assembly. The casing includes the first shell wall and the second shell wall who sets up oppositely along the first direction, and the first shell wall is equipped with pressure -relief structure, and the electrode assembly is contained in the casing, and the support structure is at least partially set up in the side of electrode assembly facing the first shell wall and is connected to the casing, and the support structure is at least partially spaced apart from the first shell wall, to form the first exhaust passage between electrode assembly and the first shell wall, and the support structure forms the containing space for containing electrode assembly between the second shell wall, and the support structure forms the communicating hole for communicating containing space and the first exhaust passage. According to the battery monomer of the utility model embodiment, the battery monomer's flow resistance of gas in exhaust passage is small, and the gas discharge efficiency is high, and the risk of explosion when battery monomer thermal runaway occurs is low.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cell, a battery device, and an electrical device. Background Technology

[0002] In related technologies, a pressure relief structure is typically installed on the casing of a battery cell to balance the pressure within the cell and reduce the risk of excessive pressure. This is achieved by placing a shim near the pressure relief structure, which creates an exhaust channel between the electrode assembly and the casing. However, the shim occupies part of the exhaust channel space. As airflow travels along the exhaust channel to the pressure relief structure, the shim obstructs the airflow, increasing the resistance to gas flow and resulting in low gas discharge efficiency. When thermal runaway occurs in the cell, the resulting high-temperature, high-pressure gas flow cannot be discharged in time, increasing the probability of the battery cell exploding. Therefore, how to reduce the exhaust resistance of the battery cell to reduce the risk of explosion due to thermal runaway remains a technical problem to be solved. Utility Model Content

[0003] In view of the above problems, the present invention provides a battery cell with low gas flow resistance in the exhaust channel, high gas discharge efficiency, and low risk of explosion in the event of thermal runaway.

[0004] In a first aspect, the present invention provides a battery cell, comprising: a housing, including a first housing wall and a second housing wall disposed opposite to each other along a first direction, the first housing wall having a pressure relief structure; an electrode assembly housed within the housing; a support structure at least partially disposed on the side of the electrode assembly facing the first housing wall and connected to the housing, the support structure at least partially spaced from the first housing wall to form a first exhaust channel between the electrode assembly and the first housing wall, a receiving space for accommodating the electrode assembly being formed between the support structure and the second housing wall, and the support structure having a communicating hole for connecting the receiving space and the first exhaust channel.

[0005] In the above technical solution, by providing a support structure inside the battery cell housing and at least partially spaced from the first housing wall, a first exhaust channel can be formed between the first housing wall and the support structure. In this way, the support structure is entirely located on the side of the first exhaust channel closer to the electrode assembly, and the indirect structure does not occupy the space within the first exhaust channel. During the process of airflow through the first exhaust channel to the pressure relief structure, there will be no airflow collision with the support structure, thus reducing the flow resistance of gas in the first exhaust channel. When the battery cell experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly can enter the first exhaust channel through the connecting holes on the support structure, and can be discharged to the pressure relief structure in a timely and smooth manner, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell experiences thermal runaway.

[0006] In some embodiments, the support structure includes a plurality of spaced-apart first support members, with the communicating holes formed between the plurality of first support members. The first support members are located between the first shell wall and the electrode assembly and are connected to the shell. The first support members are spaced apart from the first shell wall to form the first exhaust channel between the first support members and the first shell wall.

[0007] In the above technical solution, by making the support structure include multiple spaced first support members and forming connecting holes between the multiple spaced first support members, the distribution of the connecting holes can be made more uniform. When the electrode assembly experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly can be uniformly discharged into the first exhaust channel through the connecting holes, thereby reducing the risk of explosion when the battery cell experiences thermal runaway.

[0008] In some embodiments, there are multiple first support members, which are arranged at intervals along the second direction. Each first support member extends along a third direction, and both ends of the first support member along the third direction are connected to the housing. A connecting hole is formed between adjacent first support members, and the third direction, the second direction, and the first direction intersect each other.

[0009] In the above technical solution, by connecting the first support member to the shell at both ends along the third direction, the support strength of the first support member can be improved, thereby maintaining the support stability of the electrode assembly. Furthermore, by forming a connecting hole between adjacent first support members, when the battery cell experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly can be discharged more evenly into the first exhaust channel through the connecting hole, further reducing the risk of explosion when the battery cell experiences thermal runaway.

[0010] In some embodiments, the projection of the first support member onto the reference plane is a first projection, and the projection of the pressure relief structure onto the reference plane is a second projection, wherein the first projection is located on opposite sides of the second projection along the second direction.

[0011] In the above technical solution, by placing the first projection on opposite sides of the second projection along the second direction, the distribution and force of the first support member can be made more uniform, thereby enhancing the support stability of the first support member for the electrode assembly.

[0012] In some embodiments, the first projection located on the same side of the second projection along the second direction is a plurality of projections spaced apart along the second direction.

[0013] In the above technical solution, by setting the first projection located on the same side of the second projection along the second direction as multiple projections arranged at intervals along the second direction, the distribution of the first support member is made more uniform, which can improve the overall support strength of the support structure and thus maintain the support stability of the electrode assembly.

[0014] In some embodiments, among a plurality of first projections located on the same side of the second projection in the second direction, the distance between two adjacent first projections in the second direction is d, the width dimension of the first projection in the second direction is W, and the ratio of d to W ranges from 0.8 to 2.4.

[0015] In the above technical solution, by making the ratio of the distance d between two adjacent first projections in the second direction to the width W of the first projection in the second direction range from 0.8 to 2.4, it is possible to maintain the support strength of the support structure while also making the connecting area of ​​the connecting hole larger, thereby increasing the gas discharge efficiency.

[0016] In some embodiments, the first shell wall is rectangular, and the second direction is consistent with the length direction of the first shell wall.

[0017] In the above technical solution, by making the first shell wall rectangular and arranging multiple first support members at intervals along the length direction of the first shell wall, the space in the length direction of the first shell wall can be fully utilized, and the span dimension of each first support member is small, resulting in higher structural strength of a single first support member, thereby making the overall structural strength and support strength of the support structure higher.

[0018] In some embodiments, the first support member is a flat plate structure, and the thickness direction of the first support member is consistent with the first direction.

[0019] In the above technical solution, by making the first support member a flat plate structure, the structure of the first support member is simple and easy to process, and the space occupied by the first support member in the first direction within the battery cell is reduced. When the volume of the battery cell is fixed, the space ratio of the accommodating space can be increased, thereby accommodating a larger volume electrode assembly and giving the battery cell a higher energy density.

[0020] In some embodiments, the dimensions of the first support member in the first direction range from 0.8 mm to 1.5 mm.

[0021] In the above technical solution, by making the size range of the first support member in the first direction from 0.8mm to 1.5mm, it is possible to reduce the space occupied by the first support member in the first direction within the battery cell while maintaining the support strength of the support structure. When the volume of the battery cell is fixed, the space ratio of the accommodating space can be increased, thereby accommodating a larger volume electrode assembly and enabling the battery cell to have a higher energy density.

[0022] In some embodiments, the housing includes a third shell wall connected between the first shell wall and the second shell wall, and the support structure further includes a second support member connected to at least a portion of the first support member and located between the electrode assembly and the third shell wall, so that a second exhaust channel is formed between the electrode assembly and the third shell wall, and the second exhaust channel communicates with the first exhaust channel.

[0023] In the above technical solution, the second support member is connected to at least part of the first support member and is located between the electrode assembly and the third shell wall. This can limit the electrode assembly and maintain its stability. When the electrode assembly experiences thermal runaway, a second exhaust channel can be formed between the electrode assembly and the third shell wall, increasing the path for the gas generated by the electrode assembly to be discharged into the first exhaust channel. While the high-temperature and high-pressure gas generated by the electrode assembly is discharged into the first exhaust channel through the connecting hole on the support structure, it can also be discharged from the second exhaust channel into the first exhaust channel. This allows the gas generated by the electrode assembly to be discharged into the first exhaust channel through multiple paths, and then discharged to the pressure relief structure through the first exhaust channel for pressure relief. This increases the gas discharge efficiency and reduces the risk of explosion when the battery cell experiences thermal runaway.

[0024] In some embodiments, there are multiple first support members, which are spaced apart along a second direction. Each first support member extends along a third direction, and both ends of the first support member along the third direction are connected to the housing. A connecting hole is formed between adjacent first support members. The third direction, the second direction, and the first direction intersect each other. There are two third housing walls, which are located on both sides of the electrode assembly along the second direction. There are two second support members, which are located between the electrode assembly and the two third housing walls. Each second support member is connected to the first support member closest to the third housing wall.

[0025] In the above technical solution, by connecting the first support member to the housing at both ends along the third direction, the support strength of the first support member can be improved, thereby maintaining the support stability of the electrode assembly. Furthermore, by having two second support members, each of which is connected to the first support member closest to the third housing wall, the electrode assembly is limited in the second direction while ensuring sufficient space for the electrode assembly. This improves the support stability of the second support member for the electrode assembly in the second direction and also forms two second exhaust channels between the electrode assembly and the two third housing walls. This increases the path for the gas generated by the electrode assembly to be discharged into the first exhaust channel, allowing the gas generated by the electrode assembly to be discharged into the first exhaust channel through multiple paths, increasing the gas discharge efficiency and reducing the risk of explosion during thermal runaway of the battery cell.

[0026] In some embodiments, the size of the first exhaust passage in the first direction ranges from 2 mm to 6 mm.

[0027] In the above technical solution, by making the size range of the first exhaust channel in the first direction from 2mm to 6mm, the gas exhaust efficiency can be increased. While maintaining smooth airflow and pressure relief, the space occupied by the exhaust channel in the first direction within the battery cell can be reduced. When the volume of the battery cell is fixed, the space ratio of the accommodating space can be increased, thereby accommodating a larger volume electrode assembly, enabling the battery cell to have a higher energy density, and better balancing exhaust efficiency and energy density.

[0028] In some embodiments, the support structure includes a support structure body and a protective layer, the protective layer covering the surface of the support structure body, and the melting point of the protective layer being higher than that of the support structure body.

[0029] In the above technical solution, by covering the surface of the supporting structure body with a protective layer and making the melting point of the protective layer higher than that of the supporting structure body, when high temperature and high pressure gas flows through the supporting structure, the protective layer can protect the supporting structure body, so that the supporting structure body can maintain its shape stability and prevent the supporting structure body from melting and causing a decrease in the supporting strength of the supporting structure.

[0030] In some embodiments, the melting point or decomposition temperature of the protective layer is higher than 800°C.

[0031] In the above technical solution, by making the melting point or decomposition temperature of the protective layer higher than 800℃, the high-temperature stability of the protective layer is enhanced. When high-temperature and high-pressure gas flows through the support structure, the protective layer is difficult to melt or decompose, which prevents the structure from being damaged after the protective layer is melted or decomposed, and helps to maintain the support strength of the support structure.

[0032] In some embodiments, the thickness of the protective layer is 0.1 mm to 0.3 mm.

[0033] In the above technical solution, by making the thickness of the protective layer 0.1mm to 0.3mm, it can provide good protection for the supporting structure body while reducing the space ratio of the protective layer in the battery cell. When the volume of the battery cell is fixed, it can increase the space ratio of the accommodating space, thereby accommodating larger electrode components and enabling the battery cell to have a higher energy density.

[0034] In some embodiments, the supporting structure body is made of metal.

[0035] In the above technical solution, by making the support structure body a metal material, the support structure can have good support force and can bear the weight of the electrode assembly. Moreover, most metal materials have good plasticity and are easy to process.

[0036] In some embodiments, the protective layer is an inorganic material layer.

[0037] In the above technical solution, by using an inorganic material layer as a protective layer, the chemical stability and high temperature resistance of the protective layer can be improved. It is not easily decomposed or corroded under high temperature conditions, and has a long service life, thus playing a good protective role for the supporting structure.

[0038] In some embodiments, the protective layer is a polysilazane layer.

[0039] In the above technical solution, by using a polysilazane layer as a protective layer, the high temperature resistance of the protective layer can be further improved. It is not easy to fall off and fail under high temperature conditions. Moreover, the polysilazane layer has a low thermal conductivity, which enables the support structure to maintain good structural performance under the impact of high temperature and high pressure airflow during thermal runaway.

[0040] In some embodiments, the melting point or decomposition temperature of the support structure is higher than 800°C.

[0041] In the above technical solution, by making the melting point or decomposition temperature of the support structure higher than 800℃, the high-temperature stability of the support structure is enhanced. When high-temperature and high-pressure gas flows through the support structure, the support structure is difficult to melt or decompose, preventing the support structure from losing its ability to support the electrode assembly after melting or decomposition, which is beneficial to maintaining the support strength of the support structure.

[0042] In some embodiments, the support structure is welded to the housing.

[0043] In the above technical solution, by welding the support structure to the shell, the connection between the support structure and the shell can be strengthened, thereby improving the support strength of the support structure for the electrode assembly.

[0044] In some embodiments, the housing includes a third shell wall connected between the first shell wall and the second shell wall, and the support structure is welded to the third shell wall.

[0045] In the above technical solution, by welding the support structure to the third shell wall, the support structure can be prevented from contacting the first shell wall, thereby reducing the space occupied by the support structure in the first exhaust channel. When the battery cell experiences thermal runaway, it can be discharged to the pressure relief structure in a timely and smooth manner through the first exhaust channel for pressure relief.

[0046] In some embodiments, the second shell wall is provided with a pole post component, and the electrode assembly is connected to the pole post component.

[0047] In the above technical solution, by setting the electrode post component on the second shell wall, the electrode post component and the first exhaust channel can be set on opposite sides of the battery cell, which facilitates the processing of the battery cell and avoids the electrode post component and the electrode assembly's tabs from occupying the first exhaust channel. This makes the first exhaust channel a more continuous and complete channel, thereby better reducing the flow resistance of gas in the first exhaust channel and facilitating the discharge of high-temperature and high-pressure gas flow when the battery cell experiences thermal runaway.

[0048] In some embodiments, the first direction is the up-down direction, and the first shell wall is located below the second shell wall.

[0049] In the above technical solution, by placing the first shell wall below the second shell wall and using the pressure relief structure of the first shell wall for pressure relief, high-temperature and high-pressure gas can be discharged downwards. When the battery cells are assembled into a battery device and used in a vehicle, the risk of high-temperature and high-pressure gas being discharged upwards and causing damage to the vehicle interior when the battery cells experience thermal runaway can be reduced.

[0050] Secondly, the present invention provides a battery device, comprising: a housing; and a battery cell according to the first aspect embodiment, wherein the battery cell is disposed within the housing.

[0051] In the above technical solution, by setting the battery cell and providing a support structure inside the battery cell's casing, and spacing the support structure from the first casing wall, a first exhaust channel can be formed between the first casing wall and the support structure. In this way, the support structure is entirely located on the side of the first exhaust channel closer to the electrode assembly, and the indirect structure does not occupy the space within the first exhaust channel. During the process of airflow through the first exhaust channel to the pressure relief structure, there will be no airflow collision with the support structure, thus reducing the flow resistance of gas in the first exhaust channel. When the battery cell experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly can enter the first exhaust channel through the connecting holes on the support structure, and can be discharged to the pressure relief structure in a timely and smooth manner, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell experiences thermal runaway.

[0052] Thirdly, the present invention provides an electrical device, including the battery device described in the second aspect embodiment.

[0053] In the above technical solution, by setting the battery device, a support structure is provided inside the housing of the battery cell, and the support structure is spaced apart from the first housing wall. This forms a first exhaust channel between the first housing wall and the support structure. In this way, the support structure is located entirely on the side of the first exhaust channel closer to the electrode assembly. The indirect structure does not occupy the space in the first exhaust channel. During the process of airflow through the first exhaust channel to the pressure relief structure, there will be no airflow collision with the support structure, thus reducing the flow resistance of gas in the first exhaust channel. When the battery cell experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly can enter the first exhaust channel through the connecting hole on the support structure. It can be discharged to the pressure relief structure in a timely and smooth manner, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell experiences thermal runaway.

[0054] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0055] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a battery cell according to some embodiments of the present invention; Figure 2 yes Figure 1 A bottom view of a single battery cell; Figure 3 yes Figure 1 Top view of a single battery cell; Figure 4 This is a schematic diagram showing the connection between the support structure of a battery cell and the casing according to some embodiments of the present invention; Figure 5 yes Figure 1 A cross-sectional schematic diagram of a single battery cell; Figure 6 yes Figure 5 Enlarged view of point A in the middle; Figure 7 This is a cross-sectional view of the support structure according to some embodiments of the utility model; Figure 8 yes Figure 1 A cross-sectional view of a single battery cell from another angle; Figure 9 This is a schematic diagram of a battery device according to some embodiments of the present invention; Figure 10 This is a schematic diagram of an electrical device according to some embodiments of the present invention.

[0056] Figure label: 1000. Electrical appliances; 100. Battery assembly; 101. Housing; 10. Battery cells; 20. Shell; 21. First shell wall; 211. Pressure relief structure; 22. Second shell wall; 221. Pole post assembly; 23. Third shell wall; 30. Support structure; 301. First support member; 302. Second support member; 31. Support structure body; 32. Connecting hole; 33. Protective layer; 40. Electrode assembly; 50. Accommodation space; 51. First exhaust passage; 52. Second exhaust passage; 200. Vehicle body. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0058] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order or hierarchy.

[0059] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments.

[0060] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "attachment," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0061] In this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this invention, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0062] In the embodiments of this utility model, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this utility model shown in the drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this utility model.

[0063] In this utility model, "multiple" refers to two or more (including two).

[0064] In the embodiments of this utility model, unless otherwise specified, all embodiments and optional embodiments of this utility model can be combined with each other to form new technical solutions.

[0065] In the embodiments of this utility model, unless otherwise specified, all technical features and optional technical features of this utility model can be combined with each other to form new technical solutions.

[0066] In embodiments of this invention, the battery apparatus may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar. For example, a battery cell assembly is typically formed by arranging multiple battery cells; a battery cell assembly may also be a battery module, which is formed by arranging and fixing multiple battery cells into a single module. As an example, a battery module may be formed by bundling multiple battery cells together with cable ties.

[0067] The battery device can be a battery pack, which includes a housing and one or more individual battery cells housed within the housing. The individual battery cells can be battery modules, which can be housed within the housing by securing the battery modules to the housing; alternatively, multiple individual battery cells can be directly secured to the housing.

[0068] In embodiments of this invention, the housing may include a first housing and a second housing. The first housing and the second housing are fastened together to form a closed space inside the housing for housing individual battery cells. Here, "closed" refers to covering or shutting down; it can be sealed or unsealed. The first housing may be a top cover or a bottom plate. For example, the housing may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, forming a closed space inside the housing for housing individual battery cells.

[0069] In embodiments of this invention, the housing can be part of the vehicle's chassis structure. For example, a portion of the housing can be at least a part of the vehicle's floor, or a portion of the housing can be at least a part of the vehicle's crossbeams and longitudinal beams.

[0070] In this embodiment of the invention, the battery cell can be a rechargeable battery, which refers to a battery cell that can be recharged after discharge to activate the active materials and continue to be used. The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this embodiment of the invention is not limited to these types. The battery cell can be cylindrical, flat, cuboid, or other shapes, and this embodiment of the invention is not limited to these shapes either. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and this embodiment of the invention is not limited to these types either.

[0071] A battery cell, as the smallest energy unit of a battery device, includes a casing and electrode assemblies disposed within the casing. The electrode assemblies are the components within the battery cell where electrochemical reactions occur. The casing may contain one or more electrode assemblies. Electrode assemblies are mainly formed by winding or stacking positive and negative electrode plates, and typically a separator is provided between the positive and negative electrode plates. The portions of the positive and negative electrode plates containing active material constitute the main body of the electrode assembly, while the portions of the positive and negative electrode plates without active material each constitute a tab.

[0072] The positive electrode sheet may include a positive current collector and a positive electrode film layer disposed on at least one surface of the positive current collector, the positive electrode film layer including a positive electrode active material.

[0073] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive electrode film layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0074] As an example, the positive current collector can be a metal foil or a composite current collector.

[0075] The negative electrode sheet may include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, the negative electrode film layer including a negative electrode active material.

[0076] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode film layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0077] As an example, the negative electrode current collector can be made of metal foil, foam metal, or composite current collector.

[0078] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. With the continuous expansion of the application areas of power batteries, the market demand is also constantly increasing.

[0079] In related technologies, a pressure relief structure is typically installed on the casing of a battery cell to balance the pressure within the cell and reduce the risk of excessive pressure. This is achieved by placing a shim near the pressure relief structure, which creates an exhaust channel between the electrode assembly and the casing. However, the shim occupies part of the exhaust channel space. As airflow travels along the exhaust channel to the pressure relief structure, the shim obstructs the airflow, increasing the resistance to gas flow and resulting in low gas discharge efficiency. When thermal runaway occurs in the cell, the resulting high-temperature, high-pressure gas flow cannot be discharged in time, increasing the probability of the battery cell exploding. Therefore, how to reduce the exhaust resistance of the battery cell to reduce the risk of explosion due to thermal runaway remains a technical problem to be solved.

[0080] Based on this, the present invention proposes a battery cell, which includes a housing, a support structure, and an electrode assembly. The housing includes a first housing wall and a second housing wall disposed opposite to each other along a first direction. The first housing wall is provided with a pressure relief structure. The electrode assembly is accommodated within the housing. The support structure is at least partially disposed on the side of the electrode assembly facing the first housing wall and connected to the housing. The support structure is at least partially spaced from the first housing wall to form a first exhaust channel between the electrode assembly and the first housing wall. A receiving space for accommodating the electrode assembly is formed between the support structure and the second housing wall. The support structure has a communicating hole for connecting the receiving space and the first exhaust channel.

[0081] In the aforementioned battery cell, a support structure is provided inside the battery cell casing, and the support structure is at least partially spaced from the first casing wall. This forms a first exhaust channel between the first casing wall and the support structure. In this way, the support structure is entirely located on the side of the first exhaust channel closer to the electrode assembly, and the indirect structure does not occupy the space within the first exhaust channel. During the process of airflow through the first exhaust channel to the pressure relief structure, there will be no airflow collision with the support structure, thus reducing the flow resistance of gas in the first exhaust channel. When the battery cell experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly can enter the first exhaust channel through the connecting holes on the support structure, and can be discharged to the pressure relief structure in a timely and smooth manner, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell experiences thermal runaway.

[0082] The battery device disclosed in this embodiment can be used in electrical devices that use a battery device as a power source or in various energy storage systems that use a battery device as an energy storage element. Besides vehicles, the battery device can also be used in, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0083] The electrical device disclosed in this utility model embodiment can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device is installed inside the vehicle, and the battery device can be located at the bottom, front, or rear of the vehicle. The battery device can be used to power the vehicle; for example, the battery device can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller is used to control the battery device to supply power to the motor, for example, for the vehicle's starting, navigation, and operating power needs. In some embodiments of this utility model, the battery device can not only serve as the vehicle's operating power source but also as the vehicle's drive power source, replacing or partially replacing gasoline or natural gas to provide driving power for the vehicle.

[0084] The following is for reference. Figures 1-10 The battery cell 10 according to an embodiment of the present invention is described.

[0085] refer to Figures 1-5In a first aspect, the present invention provides a battery cell 10, comprising: a housing 20, a support structure 30, and an electrode assembly 40. The housing 20 includes a first housing wall 21 and a second housing wall 22 disposed opposite to each other along a first direction. The first housing wall 21 is provided with a pressure relief structure 211. The electrode assembly 40 is accommodated within the housing 20. The support structure 30 is at least partially disposed on the side of the electrode assembly 40 facing the first housing wall 21 and connected to the housing 20. The support structure 30 is at least partially spaced from the first housing wall 21 to form a first exhaust channel 51 between the electrode assembly 40 and the first housing wall 21. An accommodating space 50 for accommodating the electrode assembly 40 is formed between the support structure 30 and the second housing wall 22. The support structure 30 is formed with a communicating hole 32 for connecting the accommodating space 50 and the first exhaust channel 51.

[0086] The first shell wall 21 mentioned above can be the bottom cover of the shell 20, and the second shell wall 22 can be the top cover of the shell 20.

[0087] For example, the first direction can be referenced from the e1 direction in the figure.

[0088] For example, at least a portion of the housing 20 is made of a metallic material, such as an aluminum or steel housing.

[0089] For example, the support structure 30 may be at least partially located on the side of the electrode assembly 40 facing the first shell wall 21 and connected to the housing 20. Alternatively, a portion of the support structure 30 may be located on the side of the electrode assembly 40 facing the first shell wall 21 and connected to the housing 20, or all portions of the support structure 30 may be located on the side of the electrode assembly 40 facing the first shell wall 21 and connected to the housing 20.

[0090] For example, the support structure 30 may be at least partially spaced from the first shell wall 21. This could mean that a part of the support structure 30 is spaced from the first shell wall 21, or that all parts of the support structure 30 are spaced from the first shell wall 21.

[0091] The pressure relief structure 211 is used to release pressure from the battery cell 10. When the internal pressure of the battery cell 10 exceeds a set value, the pressure relief structure 211 can open to release pressure, allowing the gas inside the battery cell 10 to be discharged and reducing the internal pressure of the battery cell 10. For example, the pressure relief structure 211 can be a weak structure provided on the housing 20, such as a scratch structure provided on the housing 20; or, for another example, the pressure relief structure 211 can include an exhaust port provided on the housing 20 and a pressure relief valve plate provided at the exhaust port.

[0092] The support structure 30 is used to space the electrode assembly 40 and the first exhaust channel 51 and to limit the electrode assembly 40 to prevent it from moving around and blocking the first exhaust channel 51 during depressurization. When the battery cell 10 experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly 40 can be discharged to the depressurization structure 211 in a timely and smooth manner through the first exhaust channel 51, thereby increasing the gas discharge efficiency and reducing the probability of the battery cell 10 exploding.

[0093] The connecting hole 32 is used to connect the electrode assembly 40 and the first exhaust channel 51, so that the gas generated by the electrode assembly 40 can be directly discharged into the first exhaust channel 51 through the connecting hole 32, reducing the possibility of the battery cell 10 being unable to depressurize due to poor gas discharge and thus causing an explosion.

[0094] In the above technical solution, by providing a support structure 30 inside the housing 20 of the battery cell 10, and by having the support structure 30 at least partially spaced from the first housing wall 21, a first exhaust channel 51 can be formed between the first housing wall 21 and the support structure 30. In this way, the support structure 30 is entirely located on the side of the first exhaust channel 51 closer to the electrode assembly 40, and the indirect structure does not occupy the space inside the first exhaust channel 51. During the process of airflow through the first exhaust channel 51 to the pressure relief structure 211, there will be no airflow collision with the support structure 30, which would obstruct the airflow, thereby reducing the flow resistance of gas in the first exhaust channel 51. When the battery cell 10 experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly 40 can enter the first exhaust channel 51 through the connecting hole 32 on the support structure 30, and can be discharged to the pressure relief structure 211 in a timely and smooth manner, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell 10 experiences thermal runaway.

[0095] refer to Figures 4-5 In some embodiments, the support structure 30 includes a plurality of spaced first support members 301, with a connecting hole 32 formed between the plurality of first support members 301. The first support members 301 are located between the first shell wall 21 and the electrode assembly 40 and are connected to the shell 20. The first support members 301 and the first shell wall 21 are spaced apart to form a first exhaust channel 51 between the first support members 301 and the first shell wall 21.

[0096] A connecting hole 32 is formed between multiple first support members 301, which means that the gap or space between multiple first support members 301 forms a connecting hole 32.

[0097] For example, a single connecting hole 32 may be formed between multiple first support members 301, or multiple connecting holes 32 may be formed.

[0098] In the above technical solution, by making the support structure 30 include a plurality of spaced first support members 301 and forming a connecting hole 32 between the plurality of spaced first support members 301, the distribution of the connecting hole 32 can be made more uniform. When the electrode assembly 40 experiences thermal runaway, the high temperature and high pressure gas generated by the electrode assembly 40 can be uniformly discharged into the first exhaust channel 51 through the connecting hole 32, thereby reducing the risk of explosion when the battery cell 10 experiences thermal runaway.

[0099] refer to Figures 4-5 In some embodiments, there are multiple first support members 301, which are arranged at intervals along the second direction. Each first support member 301 extends along the third direction. Both ends of the first support member 301 along the third direction are connected to the housing 20. A connecting hole 32 is formed between adjacent first support members 301. The third direction, the second direction and the first direction intersect each other.

[0100] For example, the second direction can be referenced to the e2 direction in the figure, and the third direction can be referenced to the e3 direction in the figure.

[0101] For example, the first support member 301 is connected to the housing 20 at both ends along the third direction, and can be fixed by welding, snap-fitting, bonding or other connection methods.

[0102] A connecting hole 32 is formed between adjacent first support members 301, which means that the gap or space between adjacent first support members 301 is formed as a connecting hole 32.

[0103] For example, a connecting hole 32 is formed between adjacent first support members 301. When there are n first support members 301, n-1 connecting holes 32 can be formed between the first support members 301.

[0104] In the above technical solution, the first support member 301 is connected to the housing 20 at both ends along the third direction, which can improve the support strength of the first support member 301 and thus maintain the support stability of the electrode assembly 40. Furthermore, the interconnecting holes 32 formed between adjacent first support members 301 can more evenly discharge the high-temperature and high-pressure gas generated by the electrode assembly 40 into the first exhaust channel 51 through the interconnecting holes 32 when the battery cell 10 experiences thermal runaway, further reducing the risk of explosion when the battery cell 10 experiences thermal runaway.

[0105] refer to Figure 4 In some embodiments, the projection of the first support 301 onto the reference plane is a first projection, and the projection of the pressure relief structure 211 onto the reference plane is a second projection. The first projection is located on opposite sides of the second projection along the second direction.

[0106] For example, the reference plane can be a plane parallel to the first shell wall 21.

[0107] In the above technical solution, by placing the first projection on opposite sides of the second projection along the second direction, the distribution and force of the first support member 301 can be made more uniform, thereby enhancing the support stability of the first support member 301 on the electrode assembly 40.

[0108] refer to Figure 4 In some embodiments, the first projection located on the same side of the second projection along the second direction is a plurality of projections spaced apart along the second direction.

[0109] For example, there are multiple first projections arranged at intervals on both sides of the second projection along the second direction.

[0110] In the above technical solution, by setting the first projection located on the same side of the second projection along the second direction as multiple projections arranged at intervals along the second direction, the distribution of the first support member 301 is more uniform, which can improve the overall support strength of the support structure 30 and thus maintain the support stability of the electrode assembly 40.

[0111] refer to Figure 4 In some embodiments, among a plurality of first projections located on the same side of the second projection in the second direction, the distance between two adjacent first projections in the second direction is d, the width dimension of the first projection in the second direction is W, and the ratio of d to W ranges from 0.8 to 2.4.

[0112] For example, the ratio of d to W can be 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, etc. If the ratio of d to W is too large, the proportion of the distance d between two adjacent first projections in the second direction is too large, resulting in the support strength of the first support member 301 being too low; if the ratio of d to W is too small, the proportion of the width dimension W of the first projection in the second direction is too large, making it difficult for airflow to be discharged from the electrode assembly 40 to the first exhaust channel 51.

[0113] In the above technical solution, by making the ratio of the distance d between two adjacent first projections in the second direction to the width W of the first projection in the second direction range from 0.8 to 2.4, it is possible to maintain the support strength of the support structure 30 while also making the connecting area of ​​the connecting hole 32 larger, thereby increasing the gas discharge efficiency.

[0114] refer to Figure 2 In some embodiments, the first shell wall 21 is rectangular, and the second direction is consistent with the length direction of the first shell wall 21.

[0115] In the above technical solution, by making the first shell wall 21 rectangular and arranging multiple first support members 301 at intervals along the length direction of the first shell wall 21, the space in the length direction of the first shell wall 21 can be fully utilized, and the span dimension of each first support member 301 is small, resulting in higher structural strength of a single first support member 301, thereby making the overall structural strength and support strength of the support structure 30 higher.

[0116] refer to Figures 4-5 In some embodiments, the first support member 301 is a flat plate structure, and the thickness direction of the first support member 301 is consistent with the first direction.

[0117] In the above technical solution, by making the first support member 301 a flat plate structure, the structure of the first support member 301 is simple and easy to process, and the space occupied by the first support member 301 in the first direction within the battery cell 10 is reduced. When the volume of the battery cell 10 is fixed, the space ratio of the accommodating space 50 can be increased, thereby accommodating a larger volume electrode assembly 40, so that the battery cell 10 has a higher energy density.

[0118] refer to Figure 6 In some embodiments, the first support member 301 has a dimension ranging from 0.8 mm to 1.5 mm in the first direction.

[0119] The dimensions of the first support member 301 in the first direction can be referenced. Figure 6 h1 in the middle.

[0120] For example, the dimensions of the first support member 301 in the first direction can be 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc. If the dimensions of the first support member 301 in the first direction are too small, the supporting strength of the first support member 301 will be too weak, making it difficult to support the electrode assembly 40; if the dimensions of the first support member 301 in the first direction are too large, the first support member 301 will occupy too much space in the first direction within the battery cell 10, and will increase the weight of the battery cell 10.

[0121] In the above technical solution, by making the size range of the first support member 301 in the first direction from 0.8mm to 1.5mm, it is possible to reduce the space occupied by the first support member 301 in the first direction within the battery cell 10 while maintaining the support strength of the support structure 30. When the volume of the battery cell 10 is fixed, the space ratio of the accommodating space 50 can be increased, thereby accommodating a larger volume electrode assembly 40 and enabling the battery cell 10 to have a higher energy density.

[0122] refer to Figure 5In some embodiments, the housing 20 includes a third housing wall 23 connected between the first housing wall 21 and the second housing wall 22. The support structure 30 also includes a second support member 302 connected to at least a portion of the first support member 301 and located between the electrode assembly 40 and the third housing wall 23, so that a second exhaust channel 52 is formed between the electrode assembly 40 and the third housing wall 23, and the second exhaust channel 52 communicates with the first exhaust channel 51.

[0123] For example, there may be one or more third shell walls 23. The third shell wall 23 is connected between the first shell wall 21 and the second shell wall 22. The two ends of the third shell wall 23 along the first direction are respectively connected to the first shell wall 21 and the second shell wall 22. There may be one or more second support members 302. The second support member 302 may be a flat plate structure or a curved plate structure.

[0124] The second support member 302 is connected to at least a portion of the first support member 301. This connection can be either a connection between the second support member 302 and a portion of the first support member 301, or a connection between the second support member 302 and all of the first support members 301.

[0125] In the above technical solution, the second support 302 is connected to at least part of the first support 301 and is located between the electrode assembly 40 and the third shell wall 23, which can limit the electrode assembly 40 and maintain its stability. When the electrode assembly 40 experiences thermal runaway, a second exhaust channel 52 can be formed between the electrode assembly 40 and the third shell wall 23, increasing the path for the gas generated by the electrode assembly 40 to be discharged into the first exhaust channel 51. While the high-temperature and high-pressure gas generated by the electrode assembly 40 is discharged into the first exhaust channel 51 through the connecting hole 32 on the support structure 30, it can also be discharged from the second exhaust channel 52 into the first exhaust channel 51. In this way, the gas generated by the electrode assembly 40 can be discharged into the first exhaust channel 51 through multiple paths, and then discharged to the pressure relief structure 211 for pressure relief through the first exhaust channel 51, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell 10 experiences thermal runaway.

[0126] refer to Figures 4-5In some embodiments, there are multiple first support members 301, which are arranged at intervals along the second direction. Each first support member 301 extends along a third direction, and both ends of the first support member 301 along the third direction are connected to the housing 20. A connecting hole 32 is formed between adjacent first support members 301. The third direction, the second direction, and the first direction intersect each other. There are two third housing walls 23, which are located on both sides of the electrode assembly 40 along the second direction. There are two second support members 302, which are located between the electrode assembly 40 and the two third housing walls 23, respectively. Each second support member 302 is connected to the first support member 301 that is closest to the third housing wall 23.

[0127] The two second support members 302 are respectively located between the electrode assembly 40 and the two third shell walls 23, meaning that one of the second support members 302 is located between the electrode assembly 40 and one of the third shell walls 23, and the other second support member 302 is located between the electrode assembly 40 and the other third shell wall 23.

[0128] In the above technical solution, by connecting the first support member 301 to the housing 20 at both ends along the third direction, the support strength of the first support member 301 can be improved, thereby maintaining the support stability of the electrode assembly 40. Furthermore, by making two second support members 302, each of which is connected to the first support member 301 closest to the third housing wall 23, the electrode assembly 40 is limited in the second direction while ensuring sufficient accommodating space 50 for the electrode assembly 40. This improves the support stability of the second support member 302 for the electrode assembly 40 in the second direction and also forms two second exhaust channels 52 between the electrode assembly 40 and the two third housing walls 23. This increases the path for the gas generated by the electrode assembly 40 to be discharged into the first exhaust channel 51, allowing the gas generated by the electrode assembly 40 to be discharged into the first exhaust channel 51 through multiple paths, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell 10 experiences thermal runaway.

[0129] refer to Figure 6 In some embodiments, the size of the first exhaust passage 51 in the first direction ranges from 2 mm to 6 mm.

[0130] The dimensions of the first exhaust passage 51 in the first direction can be referenced. Figure 6 h2 in the middle.

[0131] For example, the dimensions of the first exhaust channel 51 in the first direction can be 2mm, 3mm, 4mm, 5mm, 6mm, etc. If the dimensions of the first exhaust channel 51 in the first direction are too large, it will occupy too much space inside the battery cell 10; if the dimensions of the first exhaust channel 51 in the first direction are too small, it will increase the flow resistance of gas inside the first exhaust channel 51, making it difficult for airflow to pass through, resulting in difficulty in depressurization.

[0132] In the above technical solution, by making the size range of the first exhaust channel 51 in the first direction from 2mm to 6mm, the gas exhaust efficiency can be increased. While maintaining smooth airflow and pressure relief, the space occupied by the exhaust channel in the first direction within the battery cell 10 can be reduced. When the volume of the battery cell 10 is fixed, the space ratio of the accommodating space 50 can be increased, thereby accommodating a larger volume electrode assembly 40, so that the battery cell 10 has a higher energy density, and can better balance exhaust efficiency and energy density.

[0133] refer to Figure 7 In some embodiments, the support structure 30 includes a support structure body 31 and a protective layer 33, the protective layer 33 covering the surface of the support structure body 31, and the melting point of the protective layer 33 being higher than that of the support structure body 31.

[0134] For example, the protective layer 33 can be a single layer or multiple layers. If the protective layer 33 is multiple layers, the melting point of each protective layer 33 is higher than the melting point of the supporting structure body 31.

[0135] In the above technical solution, by covering the surface of the support structure body 31 with the protective layer 33 and making the melting point of the protective layer 33 higher than that of the support structure body 31, when high temperature and high pressure gas flows through the support structure 30, the protective layer 33 can protect the support structure body 31, so that the support structure body 31 can maintain its shape stability and prevent the support strength of the support structure 30 from decreasing after the support structure body 31 melts.

[0136] In some embodiments, the melting point or decomposition temperature of the protective layer 33 is higher than 800°C.

[0137] For example, the melting point of the protective layer 33 can be 805℃, 810℃, 815℃, 820℃, etc.; the decomposition temperature of the protective layer 33 can be 805℃, 810℃, 815℃, 820℃, etc. If the melting point or decomposition temperature of the protective layer 33 is too low, when the high-temperature and high-pressure gas flow passes through the support structure 30, the protective layer 33 is prone to melting or decomposition, causing the high-temperature and high-pressure gas flow to directly contact the structure body, which can easily lead to the destruction of the support structure 30.

[0138] In the above technical solution, by making the melting point or decomposition temperature of the protective layer 33 higher than 800℃, the high temperature stability of the protective layer 33 is enhanced. When high temperature and high pressure gas flows through the support structure 30, the protective layer 33 is difficult to melt or decompose, preventing the structure body from being damaged after the protective layer 33 is melted or decomposed, which is conducive to maintaining the support strength of the support structure 30.

[0139] refer to Figure 7 In some embodiments, the thickness of the protective layer 33 is 0.1 mm to 0.3 mm.

[0140] The thickness of the protective layer 33 can be referenced. Figure 7 d1 in the middle.

[0141] For example, the thickness of the protective layer 33 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, etc. If the thickness of the protective layer 33 is too thick, it will increase the space occupied by the protective layer 33 in the first direction within the battery cell 10; if the thickness of the protective layer 33 is too thin, it will be difficult to protect the supporting structure body 31.

[0142] In the above technical solution, by making the thickness of the protective layer 33 0.1mm to 0.3mm, it can provide good protection for the supporting structure body 31 while reducing the space ratio of the protective layer 33 in the battery cell 10. When the volume of the battery cell 10 is fixed, it can increase the space ratio of the accommodating space 50, thereby accommodating a larger volume electrode assembly 40 and making the battery cell 10 have a higher energy density.

[0143] In some embodiments, the support structure body 31 is made of metal.

[0144] In the above technical solution, by making the support structure body 31 a metal material, the support structure 30 can have good support force and can bear the weight of the electrode assembly 40. Moreover, most metal materials have good plasticity and are easy to process.

[0145] In some embodiments, the protective layer 33 is an inorganic material layer.

[0146] Among them, inorganic materials have higher hardness, melting point, wear resistance and chemical stability.

[0147] In the above technical solution, by using an inorganic material layer as the protective layer 33, the chemical stability and high temperature resistance of the protective layer 33 can be improved. It is not easily decomposed or corroded under high temperature conditions and has a long service life, thus playing a good protective role for the supporting structure body 31.

[0148] In some embodiments, the protective layer 33 is a polysilazane layer.

[0149] Polysilazane is a high-temperature resistant thermal insulation material with low thermal conductivity. Polysilazane decomposes at high temperatures to generate stable ceramic phases such as SiCN or Si3N4, which can be used stably for a long time at high temperatures of 1200℃–1600℃.

[0150] In the above technical solution, by using a polysilazane layer as the protective layer 33, the high temperature resistance of the protective layer 33 can be further improved. It is not easy to fall off and fail under high temperature conditions. Moreover, the polysilazane layer has a low thermal conductivity, which enables the support structure 30 to maintain good structural performance under the impact of high temperature and high pressure airflow during thermal runaway.

[0151] In some embodiments, the melting point or decomposition temperature of the support structure 30 is higher than 800°C.

[0152] For example, the melting point of the support structure 30 can be 805℃, 810℃, 815℃, 820℃, etc.; the decomposition temperature of the support structure 30 can be 805℃, 810℃, 815℃, 820℃, etc. If the melting point or decomposition temperature of the support structure 30 is too low, the support structure 30 will easily melt or decompose when the high-temperature and high-pressure gas flows through it. The support structure 30 will lose its support for the electrode assembly 40, causing the electrode assembly 40 to collapse and block the first exhaust channel 51, increasing the risk of thermal runaway of the electrode assembly 40.

[0153] In the above technical solution, by making the melting point or decomposition temperature of the support structure 30 higher than 800℃, the high temperature stability of the support structure 30 is enhanced. When high temperature and high pressure gas flows through the support structure 30, the support structure 30 is difficult to melt or decompose, preventing the support structure 30 from losing its ability to support the electrode assembly 40 after being melted or decomposed, which is beneficial to maintaining the support strength of the support structure 30.

[0154] In some embodiments, the support structure 30 is welded to the housing 20.

[0155] For example, both ends of the support structure 30 are welded to the inside of the shell 20.

[0156] In the above technical solution, by welding the support structure 30 to the housing 20, the connection between the support structure 30 and the housing 20 can be strengthened, thereby improving the support strength of the support structure 30 for the electrode assembly 40.

[0157] refer to Figure 8 In some embodiments, the housing includes a third shell wall 23 connected between the first shell wall 21 and the second shell wall 22, and the support structure 30 is welded to the third shell wall 23.

[0158] For example, there can be multiple third shell walls 23, and the support structure 30 is welded to two of the multiple third shell walls 23 that are arranged opposite to each other.

[0159] In the above technical solution, by welding the support structure 30 to the third shell wall 23, the support structure 30 can be prevented from contacting the first shell wall 21, thereby reducing the space occupied by the support structure 30 in the first exhaust channel 51. When the battery cell 30 experiences thermal runaway, it can be discharged to the pressure relief structure 211 in a timely and smooth manner through the first exhaust channel 51 for pressure relief.

[0160] refer to Figure 5 In some embodiments, the second shell wall 22 is provided with a pole post component 221, and the electrode assembly 40 is connected to the pole post component 221.

[0161] For example, the tabs of the electrode assembly 40 are connected to the terminal post 221, which serves as the lead-out structure of the battery cell 10. The terminal post 221 is used to connect to the terminal post 221 of other battery cells 10 or other components.

[0162] In the above technical solution, by setting the electrode post 221 on the second shell wall 22, the electrode post 221 and the first exhaust channel 51 can be set on opposite sides of the battery cell 10, which facilitates the processing of the battery cell 10 and avoids the electrode post 221 and the electrode tab of the electrode assembly 40 from occupying the first exhaust channel 51. This makes the first exhaust channel 51 a more continuous and complete channel, thereby better reducing the flow resistance of gas in the first exhaust channel 51. When the battery cell 10 experiences thermal runaway, it is more conducive to the discharge of high temperature and high pressure gas flow.

[0163] refer to Figure 5 In some embodiments, the first direction is the up-down direction, and the first shell wall 21 is located below the second shell wall 22.

[0164] In the above technical solution, by placing the first shell wall 21 below the second shell wall 22 and using the pressure relief structure 211 of the first shell wall 21 for pressure relief, the high-temperature and high-pressure gas can be discharged downwards. When the battery cell 10 is assembled into a battery device 100 and used in a vehicle, the risk of high-temperature and high-pressure gas being discharged upwards and causing damage to the vehicle interior when the battery cell 10 experiences thermal runaway can be reduced.

[0165] refer to Figure 9 Secondly, the present invention provides a battery device 100, comprising: a housing 101 and a battery cell 10 according to the first aspect embodiment described above, wherein the battery cell 10 is disposed within the housing 101.

[0166] There can be multiple battery cells 10, and multiple battery cells 10 can form at least one set of battery cell 10 components.

[0167] In the above technical solution, by setting the battery cell 10, a support structure 30 is provided inside the housing 20 of the battery cell 10, and the support structure 30 is spaced apart from the first housing wall 21. In this way, a first exhaust channel 51 can be formed between the first housing wall 21 and the support structure 30. In the first exhaust channel 51 formed in this way, the support structure 30 is located entirely on the side of the first exhaust channel 51 closer to the electrode assembly 40. The indirect structure does not occupy the space inside the first exhaust channel 51. During the process of airflow through the first exhaust channel 51 to the pressure relief structure 211, there will be no airflow collision with the support structure 30, which will not cause airflow obstruction. This reduces the flow resistance of gas in the first exhaust channel 51. When the battery cell 10 experiences thermal runaway, the high temperature and high pressure gas generated by the electrode assembly 40 can enter the first exhaust channel 51 through the connecting hole 32 on the support structure 30. It can be discharged to the pressure relief structure 211 in a timely and smooth manner through the first exhaust channel 51 for pressure relief, which increases the gas discharge efficiency and reduces the risk of explosion when the battery cell 10 experiences thermal runaway.

[0168] refer to Figure 10 Thirdly, the present invention provides an electrical device 1000, including a battery device 100 according to the second aspect embodiment.

[0169] The electrical device 1000 can be a vehicle, and the battery device 100 can be installed at the bottom of the vehicle body 200.

[0170] In the above technical solution, by setting the battery device 100, a support structure 30 is provided inside the housing 20 of the battery cell 10, and the support structure 30 is spaced apart from the first housing wall 21. This forms a first exhaust channel 51 between the first housing wall 21 and the support structure 30. In this way, the support structure 30 is located entirely on the side of the first exhaust channel 51 closer to the electrode assembly 40. The indirect structure does not occupy the space inside the first exhaust channel 51. During the process of airflow through the first exhaust channel 51 to the pressure relief structure 211, there will be no airflow collision with the support structure 30, which would obstruct the airflow. This reduces the flow resistance of gas in the first exhaust channel 51. When the battery cell 10 experiences thermal runaway, the high-temperature and high-pressure gas generated by the electrode assembly 40 can enter the first exhaust channel 51 through the connecting hole 32 on the support structure 30. It can be discharged to the pressure relief structure 211 in a timely and smooth manner through the first exhaust channel 51 for pressure relief, increasing the gas discharge efficiency and reducing the risk of explosion when the battery cell 10 experiences thermal runaway.

[0171] The following reference Figures 1-8 The battery cell 10 is described according to some embodiments of the present invention.

[0172] Reference Figures 1-8 In this embodiment, the battery cell 10 includes a housing 20, a support structure 30, and an electrode assembly 40. The housing 20 includes a first housing wall 21 and a second housing wall 22 disposed opposite to each other along a first direction, and two third housing walls 23 connected between the first housing wall 21 and the second housing wall 22. The electrode assembly 40 is housed within the housing 20. The support structure 30 includes a plurality of spaced-apart first support members 301 and second support members 302 connected to a portion of the first support members 301. The support structure 30 is welded to the housing 20. The first support members 301 are located between the first housing wall 21 and the electrode assembly 40. The first support members 301 and the first housing wall 21 are spaced apart to form a first exhaust channel 51 between the first support members 301 and the first housing wall 21. The side of the support structure 30 facing away from the first housing wall 21, together with the housing 20, defines an accommodating space 50. A connecting hole 32 is formed between the plurality of first support members 301 to connect the accommodating space 50 and the first exhaust channel 51.

[0173] The first shell wall 21 is rectangular, and the second direction is consistent with the length direction of the first shell wall 21. The first shell wall 21 is provided with a pressure relief structure 211. The second shell wall 22 is provided with an electrode post component 221. The electrode assembly 40 is connected to the electrode post component 221. Two third shell walls 23 are located on both sides of the electrode assembly 40 along the second direction. The second support 302 is connected to the first support 301 that is closest to the third shell wall 23.

[0174] The first support member 301 is a flat plate structure. The thickness direction of the first support member 301 is consistent with the first direction. The dimension of the first support member 301 in the first direction is 1mm. The dimension of the first exhaust channel 51 in the first direction is 4mm.

[0175] The projection of the first support member 301 onto the reference plane is the first projection, and the projection of the pressure relief structure 211 onto the reference plane is the second projection. The first projections are located on opposite sides of the second projection along the second direction. The first projections located on the same side of the second projection along the second direction are multiple projections arranged at intervals along the second direction. Among the multiple first projections located on the same side of the pressure relief structure 211 in the second direction, the distance between two adjacent first projections in the second direction is d, the width dimension of the first projection in the second direction is W, and the ratio of d to W is 2.

[0176] The second support member 302 is located between the electrode assembly 40 and the third shell wall 23, so that a second exhaust channel 52 is formed between the electrode assembly 40 and the third shell wall 23, and the second exhaust channel 52 is connected to the first exhaust channel 51.

[0177] The support structure 30 also includes a support structure body 31 and a protective layer 33. The support structure body 31 is made of metal, and the protective layer 33 is a polysilazane layer. The protective layer 33 covers the surface of the support structure body 31 and the melting point of the protective layer 33 is higher than that of the support structure body 31. The thickness of the protective layer 33 is 0.2 mm.

[0178] The following describes thermal runaway tests on battery cells of some embodiments of the present invention and battery cells in related technologies to further illustrate the battery cells of the present invention.

[0179] The battery cells in some embodiments of this utility model and in related technologies have the same capacity, for example, the capacity of the battery cell is 100A. The battery cells in this embodiment and in related technologies all underwent three sets of thermal runaway tests. The thermal runaway test was conducted with a heating film built into the battery cell. The test results are shown in Table 1 below.

[0180] Table 1

[0181] As shown in Table 1, all three sets of battery cells in the related technologies exploded when thermal runaway occurred. In this embodiment, however, the three sets of battery cells did not explode, and directional pressure relief was achieved through the pressure relief structure. Compared to the battery cells in the related technologies, the battery cells in this embodiment have a higher directional pressure relief rate and a lower risk of explosion.

[0182] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0183] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery cell, characterized in that, include: The housing includes a first shell wall and a second shell wall disposed opposite to each other along a first direction, wherein the first shell wall is provided with a pressure relief structure; Electrode assembly, housed within the housing; A support structure is at least partially disposed on the side of the electrode assembly facing the first shell wall and connected to the housing. The support structure is at least partially spaced from the first shell wall to form a first exhaust channel between the electrode assembly and the first shell wall. A receiving space for accommodating the electrode assembly is formed between the support structure and the second shell wall. The support structure has a connecting hole for connecting the receiving space and the first exhaust channel.

2. The battery cell according to claim 1, characterized in that, The support structure includes a plurality of spaced-apart first support members, with a connecting hole formed between the plurality of first support members. The first support members are located between the first shell wall and the electrode assembly and are connected to the shell. The first support members are spaced apart from the first shell wall to form the first exhaust channel between the first support members and the first shell wall.

3. The battery cell according to claim 2, characterized in that, There are multiple first support members, which are arranged at intervals along the second direction. Each first support member extends along the third direction, and both ends of the first support member along the third direction are connected to the housing. A connecting hole is formed between adjacent first support members. The third direction, the second direction, and the first direction intersect each other.

4. The battery cell according to claim 3, characterized in that, The projection of the first support member onto the reference plane is the first projection, and the projection of the pressure relief structure onto the reference plane is the second projection. The first projection is located on opposite sides of the second projection along the second direction.

5. The battery cell according to claim 4, characterized in that, The first projection located on the same side of the second projection along the second direction is a plurality of projections spaced apart along the second direction.

6. The battery cell according to claim 5, characterized in that, Among the plurality of first projections located on the same side of the second projection in the second direction, the distance between two adjacent first projections in the second direction is d, the width dimension of the first projection in the second direction is W, and the ratio of d to W ranges from 0.8 to 2.

4.

7. The battery cell according to claim 3, characterized in that, The first shell wall is rectangular, and the second direction is consistent with the length direction of the first shell wall.

8. The battery cell according to claim 2, characterized in that, The first support member is a flat plate structure, and the thickness direction of the first support member is consistent with the first direction.

9. The battery cell according to claim 2, characterized in that, The dimensions of the first support member in the first direction range from 0.8 mm to 1.5 mm.

10. The battery cell according to claim 2, characterized in that, The housing includes a third shell wall connected between the first shell wall and the second shell wall. The support structure further includes a second support member connected to at least a portion of the first support member and located between the electrode assembly and the third shell wall, so that a second exhaust channel is formed between the electrode assembly and the third shell wall, and the second exhaust channel communicates with the first exhaust channel.

11. The battery cell according to claim 10, characterized in that, There are multiple first support members, which are arranged at intervals along the second direction. Each first support member extends along the third direction. Both ends of the first support member along the third direction are connected to the shell. A connecting hole is formed between adjacent first support members. The third direction, the second direction, and the first direction intersect each other. There are two third shell walls, which are located on both sides of the electrode assembly along the second direction. There are also two second supports, which are located between the electrode assembly and the two third shell walls respectively. Each second support is connected to the first support closest to the third shell wall.

12. The battery cell according to claim 1, characterized in that, The dimensions of the first exhaust passage in the first direction range from 2mm to 6mm.

13. The battery cell according to claim 1, characterized in that, The support structure includes a support structure body and a protective layer. The protective layer covers the surface of the support structure body and has a melting point higher than that of the support structure body.

14. The battery cell according to claim 13, characterized in that, The melting point or decomposition temperature of the protective layer is higher than 800°C; and / or the thickness of the protective layer is 0.1 mm to 0.3 mm.

15. The battery cell according to claim 13, characterized in that, The supporting structure body is made of metal; and / or the protective layer is an inorganic material layer.

16. The battery cell according to claim 13, characterized in that, The protective layer is a polysilazane layer.

17. The battery cell according to claim 1, characterized in that, The melting point or decomposition temperature of the support structure is higher than 800°C.

18. The battery cell according to claim 1, characterized in that, The support structure is welded to the shell.

19. The battery cell according to claim 18, characterized in that, The housing includes a third shell wall, which is connected between the first shell wall and the second shell wall, and the support structure is welded to the third shell wall.

20. The battery cell according to any one of claims 1-19, characterized in that, The second shell wall is provided with a pole post component, and the electrode assembly is connected to the pole post component; and / or, the first direction is the up-down direction, and the first shell wall is located below the second shell wall.

21. A battery device, characterized in that, include: Box; The battery cell according to any one of claims 1-20 is disposed in the housing.

22. An electrical appliance, characterized in that, Includes the battery device as described in claim 21.

Images