Battery cell, battery device, and electric device

Abstract

The application relates to the technical field of battery structures, and provides a battery monomer, a battery device and a power utilization device. At least one folding part is arranged on an insulating part of the battery monomer, and the folding part is at least partially annularly arranged on an electrode assembly in a winding direction of the electrode assembly. The battery monomer provided by the embodiment of the application has the following advantages: when the electrode assembly does not expand, the insulating part with the folding part has a better winding protection effect on the electrode assembly; and after the electrode assembly expands, the folding part can be forced to expand and cope with the expanded electrode assembly, so that the influence of the expansion of the electrode assembly on the winding protection of the insulating part is lower; therefore, the insulating part can be simultaneously applied to the electrode assembly before and after expansion.

Description

Technical Field

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

[0002] With the development of new energy technologies, batteries are being used more and more widely, such as in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools.

[0003] A single battery cell includes an end cap, a housing, and an electrode assembly and an insulating film housed within the housing. The insulating film covers the electrode assembly for insulation protection. Since the electrode assembly expands during operation, a gap must be maintained between the housing and the electrode assembly to accommodate this expansion.

[0004] However, when the electrode assembly expands, its width increases, requiring a larger area of ​​insulating film covering the side of the electrode assembly opposite to the end cap. This results in a reduction in the length of the insulating film covering the electrode assembly in the winding direction. Consequently, the insulating film provides poor protection for the expanded electrode assembly. If the size of the insulating film is increased to accommodate the expanded electrode assembly, the length of the insulating film covering the electrode assembly in the winding direction parallel to the electrode assembly becomes excessive during battery cell manufacturing. This can affect the assembly of the end cap onto the housing and complicate the welding process. Summary of the Invention

[0005] The purpose of this application is to provide a battery cell, a battery device, and an electrical device, aiming to solve the problem that the insulating film of related technologies cannot be simultaneously applied to electrode assemblies before and after expansion.

[0006] To achieve the above objectives, the technical solution adopted in the embodiments of this application is as follows:

[0007] In a first aspect, embodiments of this application provide a battery cell including a housing, an electrode assembly, and an insulating member. The housing has a receiving cavity inside, the electrode assembly is housed in the receiving cavity, the insulating member is housed in the receiving cavity, the insulating member is disposed between the electrode assembly and the housing, and the insulating member has at least one folded portion, which is at least partially circumferentially disposed around the electrode assembly in the winding direction of the electrode assembly.

[0008] The beneficial effects of the embodiments of this application are as follows: The battery cell provided in the embodiments of this application has a folded part on the insulating part. When the electrode assembly does not expand, the insulating part with the folded part has a better wrapping protection effect on the electrode assembly. After the electrode assembly expands, the structure formed by the folded part can be unfolded under force and cope with the expanded electrode assembly, so that the expansion of the electrode assembly has a low impact on the wrapping protection of the insulating part. Thus, the insulating part can be used for both the electrode assembly before and after expansion.

[0009] In some embodiments, the housing includes a first wall and a second wall circumferentially disposed on the first wall, with a fold located between the electrode assembly and the second wall.

[0010] By adopting the above technical solution, the folded part can be formed between the second wall and the electrode assembly. When the electrode assembly expands, the electrode assembly applies a force to the insulating part so that the folded part can unfold, thereby reducing the effect of the electrode assembly expansion pulling on the insulating part and thus affecting the wrapping protection of the electrode assembly.

[0011] In some embodiments, the housing includes an end cap connected to one end of the second wall facing away from the first wall, and a folded portion located at one end of the insulating member facing the first wall.

[0012] By adopting the above technical solution, the folded part is located at the end of the insulating part facing the first wall, that is, the folded part is away from the end cap, so as to reduce the impact of the folded part on the connection operation between the second wall and the end cap.

[0013] In some embodiments, a gap exists between the electrode assembly and the second wall, and the fold abuts against the electrode assembly and the second wall.

[0014] By adopting the above technical solution, the folded part can limit the electrode assembly, effectively reducing the probability of the electrode assembly shaking, thereby improving the stability of the battery cell.

[0015] In some embodiments, the housing includes a first wall and a second wall circumferentially disposed on the first wall, with a fold located between the first wall and the electrode assembly.

[0016] By adopting the above technical solution, the folded part can be located between the first wall and the electrode assembly. When the electrode assembly expands, the electrode assembly applies a force to the insulating part so that the folded part can unfold, thereby reducing the impact of the electrode assembly expansion on the insulating part and the resulting pulling on the electrode assembly, which would otherwise affect the protection of the electrode assembly.

[0017] In some embodiments, the insulating element has at least two fold lines.

[0018] By adopting the above technical solution, the fold lines can be used to more easily bend and form a folded part.

[0019] In some embodiments, the insulating member includes a first insulating portion, two second insulating portions connected to opposite ends of the first insulating portion, and a third insulating portion connected to opposite ends of the two second insulating portions respectively; a first bending crease and a folding crease are provided between the first insulating portion and the second insulating portion, and a second bending crease is provided between the second insulating portion and the third insulating portion.

[0020] By adopting the above technical solution, the second insulating part can be folded around the first bending crease, and the third insulating part can be folded around the second bending crease, so that the first insulating part, the second insulating part, and the third insulating part respectively cover different sides of the electrode assembly; and the folding crease can help form the folded part.

[0021] In some embodiments, the folded portion has an unfolded length w; wherein, 0.5 mm ≤ w ≤ 10 mm.

[0022] By adopting the above technical solution, the unfolded length w of the folded part is limited to greater than or equal to 0.5 mm and less than or equal to 10 mm. As a result, the electrode assembly expands so that the folded part can unfold to a length of 0.5 mm to 10 mm, thereby reducing the pulling effect of the electrode assembly expansion on the insulating part.

[0023] In some embodiments, 1mm ≤ w ≤ 6mm.

[0024] By adopting the above technical solution, the unfolded length w of the folded part is limited to greater than or equal to 1 mm and less than or equal to 6 mm. The electrode assembly expands so that the folded part can unfold to a length of 1 mm to 6 mm, thereby reducing the pulling effect of the electrode assembly expansion on the insulating part.

[0025] In some embodiments, the thickness of the electrode assembly is a, 10 mm ≤ a ≤ 80 mm; the expansion rate of the electrode assembly is k, 5% ≤ a ≤ 45%; the folded portion has an unfolded length w; wherein, 0.25 mm ≤ w ≤ 18 mm.

[0026] By adopting the above technical solution, when the thickness a of the electrode assembly is in the range of 10 mm to 80 mm and the expansion rate k of the electrode assembly is in the range of 5% to 45%, the unfolded length w of the folded part can be limited to greater than or equal to 0.25 mm and less than or equal to 18 mm, so that when the folded part is not unfolded, the insulating part can better wrap and protect the electrode assembly, and after the electrode assembly expands, the unfolded folded part can meet the expansion requirements of the electrode assembly, so that the insulating part can still better wrap and protect the electrode assembly.

[0027] In some embodiments, 1mm ≤ w ≤ 10mm.

[0028] By adopting the above technical solution, the unfolded length w of the folded part is further limited to greater than or equal to 1 mm and less than or equal to 10 mm, so that the insulating part can form better wrapping protection for the electrode assembly before and after expansion.

[0029] Secondly, embodiments of this application provide a battery device including a plurality of battery cells as described above.

[0030] The beneficial effects of the embodiments of this application are as follows: The battery device provided in the embodiments of this application includes the above-mentioned battery cell. In the battery cell, the insulating member can meet the wrapping protection requirements before and after the electrode assembly expands by setting a folded part. Therefore, the battery device has better stability.

[0031] Thirdly, embodiments of this application provide an electrical device, including a battery cell and a battery device as described above, wherein the battery cell or battery device is used to store or provide electrical energy.

[0032] The beneficial effects of the embodiments of this application are as follows: The electrical device provided in the embodiments of this application includes the above-mentioned battery cell or battery device, therefore, the stability of the electrical device is better. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the vehicle structure provided in an embodiment of this application;

[0035] Figure 2 An exploded view of the battery device provided in the embodiments of this application;

[0036] Figure 3 This is an exploded structural diagram of a battery cell provided in an embodiment of this application;

[0037] Figure 4 A top view of the electrode assembly provided in an embodiment of this application;

[0038] Figure 5 This is a schematic diagram of the structure of the electrode assembly with external insulation provided in the embodiments of this application;

[0039] Figure 6 This is a cross-sectional view of the electrode assembly provided in the embodiments of this application when it is wrapped with an insulating component;

[0040] Figure 7 for Figure 6 A magnified view of part A;

[0041] Figure 8 A schematic diagram of the unfolded structure of the insulating component provided in the embodiments of this application;

[0042] Figure 9 This is a schematic diagram of the structure provided in an embodiment of this application when the folded portion is disposed between the electrode assembly and the first wall.

[0043] The following are the labeling elements in the figure:

[0044] 1000, vehicles;

[0045] 100. Battery assembly; 200. Controller; 300. Motor;

[0046] 10. Box; 11. First box; 12. Second box;

[0047] 20. Battery cell; 210. Casing; 21. End cap; 21a. Electrode terminal; 211. Insulation structure; 22. Housing; 22a. Receiving cavity; 221. First wall; 222. Second wall; 23. Electrode assembly; 23a. Tab; 231. Straight part; 232. Bending part;

[0048] 24. Insulating part; 24a. Fold crease; 24b. First bend crease; 24c. Second bend crease; 241. First insulating part; 242. Second insulating part; 243. Third insulating part; 25. Fold part

[0049] X, winding direction. Detailed Implementation

[0050] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0051] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0053] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0054] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.

[0055] During battery charge-discharge cycles, the electrode plates (especially the negative electrode plate) of the electrode assembly thicken due to material expansion, leading to overall expansion of the electrode assembly. When the electrode assembly is not expanding, the insulating film provides good wrapping protection. However, with expansion, the increased overall size of the electrode assembly necessitates a larger insulating film. If the insulating film covering the electrode assembly surface lacks sufficient length, it cannot fully cover the expanded electrode assembly, resulting in poor insulation protection. Conversely, if the insulating film has sufficient expansion length, when the electrode assembly is not expanding, its length may cause it to protrude beyond the end of the housing, potentially affecting the assembly of the end cap and the welding process.

[0056] Based on the above considerations, to address the issue that insulating films in related technologies cannot be simultaneously applied to electrode assemblies before and after expansion, a battery cell was designed with unfoldable folds on its insulating component. When the electrode assembly is not expanded, the insulating component with folds can adequately wrap and protect the electrode assembly without extending beyond the outer casing and affecting its assembly. After the electrode assembly expands, the expanded electrode assembly applies a force to the insulating component, causing the folds to unfold. This allows the unfolded folds to meet the dimensional requirements of the expanded electrode assembly, thereby reducing the impact of electrode expansion on the wrapping protection of the insulating component. Therefore, the insulating component with folds can be applied to electrode assemblies both before and after expansion.

[0057] The battery cells disclosed in this application can be used in electrical devices that use battery devices as power sources or in various energy storage systems that use batteries as energy storage elements. Electrical devices can be, but are 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.

[0058] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0059] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 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 100 is provided inside the vehicle 1000, and the battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.

[0060] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0061] Please refer to Figure 2, Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells 20, which are connected in series, parallel, or mixed connections via busbars.

[0062] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells 20.

[0063] As an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells 20 together. As an example, the battery module can also be formed by bundling multiple battery cells 20 together with cable ties.

[0064] In some embodiments, the battery device 100 may be a battery pack, which includes a housing 10 and one or more individual battery cells housed within the housing 10.

[0065] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing 10 by fixing the battery module in the housing 10.

[0066] As an example, the battery cell assembly can also be housed in the housing 10 by directly fixing multiple battery cells 20 to the housing 10.

[0067] As an example, the housing 10 may include a first housing 11 and a second housing 12. The first housing 11 and the second housing 12 are fastened together to form a closed space inside the housing 10 to house the battery cell assembly. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing 11 may be a top cover or a bottom plate.

[0068] As an example, the housing 10 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 10 forms an enclosed space to accommodate the battery cell assembly.

[0069] In some embodiments, the housing 10 may be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 may be at least a portion of the floor of the vehicle 1000, or a portion of the housing 10 may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000.

[0070] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells 20, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0071] In this embodiment of the application, the battery cell 20 can be a secondary battery, which refers to a battery cell 20 that can be used again after being discharged by recharging to activate the active materials.

[0072] The battery cell 20 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 the embodiments of this application are not limited to this.

[0073] Please refer to Figure 3 , Figure 3 This is an exploded structural diagram of a battery cell 20 provided in some embodiments of this application. The battery cell 20 refers to the smallest unit constituting the battery device 100. For example... Figure 3 The battery cell 20 includes a housing 210 (e.g., end cap 21, housing 22), an electrode assembly 23, and other functional components.

[0074] End cap 21 refers to a component that covers the opening of housing 22 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 21 can be adapted to the shape of housing 22 to fit it. Optionally, end cap 21 can be made of a material with certain hardness and strength (such as aluminum alloy), so that end cap 21 is not easily deformed under pressure and impact, allowing battery cell 20 to have higher structural strength and improved reliability. Functional components such as electrode terminals 21a can be provided on end cap 21. Electrode terminals 21a can be used for electrical connection with electrode assembly 23 to output or input electrical energy to battery cell 20. In some embodiments, end cap 21 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of battery cell 20 reaches a threshold. The material of end cap 21 can also be various, such as, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, an insulating structure 211 may be provided on the inner side of the end cap 21. The insulating structure 211 can be used to isolate the electrical connection components inside the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating structure 211 may be made of plastic, rubber, etc.

[0075] The housing 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 23, electrolyte, and other components. The housing 22 and the end cap 21 can be independent components. An opening can be provided on the housing 22, and the end cap 21 closes the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 21 and the housing 22 can be integrated. Specifically, the end cap 21 and the housing 22 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 22, the end cap 21 closes the housing 22. The housing 22 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the electrode assembly 23. The housing 22 can be made of various materials, such as, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0076] Electrode assembly 23 is the component in the battery cell 20 where electrochemical reactions occur. The casing 22 may contain one or more electrode assemblies 23. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly 23, while the portions of the positive and negative electrode sheets without active material each constitute a tab 23a. The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs 23a connect to the electrode terminals 21a to form a current loop.

[0077] According to some embodiments of this application, refer to Figure 3 , Figure 5 and Figure 6 In a first aspect, embodiments of this application provide a battery cell 20, including a housing 210, an electrode assembly 23, and an insulating member 24. The housing 210 has a receiving cavity 22a inside, the terminal electrode assembly 23 is housed in the receiving cavity 22a, the insulating member 24 is housed in the receiving cavity 22a, the insulating member 24 is disposed between the electrode assembly 23 and the housing 210, and the insulating member 24 has at least one folded portion 25, the folded portion 25 is at least partially circumferentially disposed around the electrode assembly 23 in the winding direction X of the electrode assembly 23.

[0078] The insulating component 24 is an insulating structure that wraps around the surface of the electrode assembly 23 and serves to insulate the electrode assembly 23 from the outer casing 210, thereby reducing the probability of leakage in the electrode assembly 23. The insulating component 24 may be, but is not limited to, an insulating film, an insulating sheet, or other similar structures.

[0079] The insulating member 24 may be wrapped around the surface of the electrode assembly 23 and attached to the surface of the electrode assembly 23; or, the insulating member 24 may wrap around the electrode assembly 23 and form a gap with a portion of the surface of the electrode assembly 23.

[0080] The folded portion 25 refers to the local structure of the insulating component 24 stacked by means of winding, folding, bending, etc.; and the folded portion 25 can be unfolded under the action of force, for example, when the electrode assembly 23 expands, the electrode assembly 23 exerts a force on the insulating component 24, causing the folded portion 25 to be stretched and unfolded, thereby increasing the overall size of the insulating component 24 to meet the size requirements of the expanded electrode assembly 23 on the insulating component 24.

[0081] For example, the folded portion 25 may be folded by the partial insulating member 24 to form a stacked structure, such as a “U” shape, a triangle shape, a wave shape, etc.; or, the folded portion 25 may also be rolled by the partial insulating member 24 to form a columnar folded structure, etc.

[0082] Optionally, the fold 25 can be provided at any point on the insulating member 24; the number of folds 25 can be one or more.

[0083] The insulating member 24 forms a fold 25 around the winding direction X of the electrode assembly 23. As the electrode assembly 23 expands radially outward, the fold 25 formed around the winding direction X can be unfolded, increasing the dimension of the insulating member 24 parallel to the winding direction X of the electrode assembly 23. This increased dimension is sufficient to cover the radially expanded area of ​​the electrode assembly 23, thus meeting the dimensional requirements of the insulating member 24 due to the expansion of the electrode assembly 23. Alternatively, the insulating member 24 may form the fold 25 around the entire winding direction X of the electrode assembly 23; or, the insulating member 24 may form the fold 25 only partially around the winding direction X of the electrode assembly 23.

[0084] It should be understood that the winding direction X of the electrode assembly 23 mentioned above refers to the direction in which the cathode electrode and the anode electrode are wound to form the electrode assembly.

[0085] The battery cell 20 provided in this application embodiment has an unfoldable folded portion 25 on the insulating member 24. When the electrode assembly 23 does not expand, the insulating member 24 with the folded portion 25 provides better wrapping protection for the electrode assembly 23. After the electrode assembly 23 expands, the folded portion 25 can unfold to cope with the expanded electrode assembly 23, so that the expansion of the electrode assembly 23 has a lower impact on the wrapping protection of the insulating member 24. Thus, the insulating member 24 can be used for the electrode assembly 23 before and after expansion.

[0086] Please refer to Figure 3 , Figure 6 and Figure 7 In some embodiments, the housing 210 includes a first wall 221 and a second wall 222 surrounding the first wall 221, with the fold 25 located between the electrode assembly 23 and the second wall 222.

[0087] Understandably, the first wall 221 and the second wall 222 can together enclose and form a receiving cavity 22a, that is, the first wall 221 and the second wall 222 are two parts of the housing 22; thereby, the electrode assembly 23 and the insulating member 24 are housed within the first wall 221 and the second wall 222.

[0088] The fold 25 is disposed on the portion of the insulating member 24 located between the second wall 222 and the electrode assembly 23; optionally, the fold 25 can be disposed anywhere between the second wall 222 and the electrode assembly 23; one or more folds 25 can be disposed between the second wall 222 and the electrode assembly 23. For example, the fold 25 can be disposed close to the first wall 221; or, the insulating member 24 can be disposed away from the first wall 221, etc.

[0089] With this configuration, the fold 25 can be located between the second wall 222 and the electrode assembly 23. When the electrode assembly 23 expands, the electrode assembly 23 applies a force to the insulating member 24 so that the fold 25 can unfold, thereby reducing the effect of the expansion of the electrode assembly 23 on the insulating member 24 and the resulting wrapping protection of the electrode assembly 23.

[0090] Please refer to Figure 3 , Figure 6 and Figure 7 In some embodiments, the housing 210 includes an end cap 21 connected to one end of the second wall 222 facing away from the first wall 221, and a fold 25 located at one end of the insulating member 24 facing the first wall 221.

[0091] The end cap 21 can be welded to the second wall 222 to form an integral unit, and the end cap 21 is used to seal the receiving cavity 22a. Optionally, the insulating component 24 can be connected to the insulating structure 211 of the end cap 21 by means of bonding, heat fusion or other methods.

[0092] Optionally, the fold 25 may be located between the insulating member 24 and the second wall 222 and the electrode assembly 23 and at the end facing the first wall 221; or, the fold 25 may form a gap with the first wall 221.

[0093] With this configuration, the fold 25 is located at the end of the insulating member 24 facing the first wall 221, that is, the fold 25 is away from the end cap 21, so as to reduce the impact of the fold 25 on the connection operation between the second wall 222 and the end cap 21.

[0094] Please refer to Figure 3 , Figure 6 and Figure 7 In some embodiments, there is a gap (not shown) between the electrode assembly 23 and the second wall 222, and the fold 25 abuts against the electrode assembly 23 and the second wall 222.

[0095] Understandably, a gap is provided between the electrode assembly 23 and the second wall 222 to allow the expansion of the electrode assembly 23 to pass through, thereby reducing the damage to the second wall 222 caused by the expansion of the electrode assembly 23.

[0096] Meanwhile, due to the gap between the electrode assembly 23 and the second wall 222, the electrode assembly 23 may wobble, resulting in poor stability of the electrode assembly 23.

[0097] With this configuration, the folded portion 25 can simultaneously abut against the electrode assembly 23 and the second wall 222. Thus, the folded portion 25 can provide limiting support for the electrode assembly 23, thereby effectively reducing the probability of the electrode assembly 23 shaking and improving the stability of the battery cell 20.

[0098] Please refer to Figure 3 and Figure 9 In some embodiments, the housing 210 includes a first wall 221 and a second wall 222 surrounding the first wall 221, with the fold 25 located between the first wall 221 and the electrode assembly 23.

[0099] Understandably, the first wall 221 and the second wall 222 can together enclose and form a receiving cavity 22a, that is, the first wall 221 and the second wall 222 are two parts of the housing; thereby, the electrode assembly 23 and the insulating member 24 are housed within the first wall 221 and the second wall 222.

[0100] The fold portion 25 is disposed on the portion of the insulating member 24 located between the first wall 221 and the electrode assembly 23; optionally, the fold portion 25 can be disposed anywhere between the first wall 221 and the electrode assembly 23; one or more fold portions 25 can be disposed between the first wall 221 and the electrode assembly 23. For example, the fold portion 25 can be disposed close to the second wall 222; or, the fold portion 25 can be disposed close to the center of the first wall 221, etc.

[0101] With this configuration, the fold 25 can be formed between the first wall 221 and the electrode assembly 23. When the electrode assembly 23 expands, the electrode assembly 23 applies a force to the insulating member 24 so that the fold 25 can unfold, thereby reducing the effect of the expansion of the electrode assembly 23 on the insulating member 24 and the resulting wrapping protection of the electrode assembly 23.

[0102] Please refer to Figures 6 to 8In some embodiments, the insulating member 24 is provided with at least two fold lines 24a.

[0103] The fold crease 24a is used to assist in forming the folded part 25; when the insulating part 24 is wound, bent or otherwise folded, it can be quickly folded around the fold crease 24a, so that the folded part 25 can be formed quickly and accurately.

[0104] The number of fold lines 24a can be two, three, or more; different folds 25 can be formed by folding according to the different number of fold lines 24a.

[0105] With this configuration, the fold 24a can be used to more easily bend the fold to form the folded part 25.

[0106] It should be understood that in other embodiments, the insulating member 24 may not have fold creases 24a. For example, when a portion of the insulating member 24 is wound to form a wavy or columnar folded portion 25, since the folded portion 25 is formed by winding, there is no need to provide fold creases 24a.

[0107] Please refer to Figures 5 to 8 In some embodiments, the insulating member 24 includes a first insulating portion 241, two second insulating portions 242 connected to opposite ends of the first insulating portion 241, and a third insulating portion 243 connected to opposite ends of the two second insulating portions 242 respectively; a first bending crease 24b and a folding crease 24a are provided between the first insulating portion 241 and the second insulating portion 242, and a second bending crease 24c is provided between the second insulating portion 242 and the third insulating portion 243.

[0108] Optionally, the first insulating portion 241 may be, but is not limited to, a polygonal film structure such as a spherical film structure or a rectangular film structure. The first insulating portion 241 may be disposed between the electrode assembly 23 and the first wall 221 of the housing 22.

[0109] The second insulating portion 242 may be, but is not limited to, a polygonal film structure such as a spherical film structure or a rectangular film structure. The second insulating portion 242 may be disposed between the electrode assembly 23 and the second wall 222 of the housing 22.

[0110] The third insulating portion 243 may be, but is not limited to, a polygonal film structure such as a spherical film structure or a rectangular film structure. The third insulating portion 243 may be disposed between the electrode assembly 23 and the second wall 222 of the housing 22, and the third insulating portion 243 and the second insulating portion 242 are located on different surfaces of the electrode assembly 23.

[0111] Thus, the first insulating portion 241, the two second insulating portions 242 located at opposite ends of the first insulating portion 241, and the four third insulating portions 243 located at opposite ends of the second insulating portions 242 can cover the surface of the electrode assembly 23 to achieve insulation protection. It can be understood that the third insulating portion 243 on one side of one of the second insulating portions 242 and the third insulating portion 243 on the same side of the other second insulating portion 242 can jointly cover the same side surface of the electrode assembly 23 to achieve protection.

[0112] A first bending crease 24b is provided between the first insulating portion 241 and the second insulating portion 242. For example, a second insulating portion 242 is provided on each opposite side of the first insulating portion 241. Therefore, a first bending crease 24b is provided between each of the two second insulating portions 242 and the first insulating portion 241. Thus, the two second insulating portions 242 located on opposite sides of the first insulating portion 241 can be folded around their respective first bending creases 24b, so that the two second insulating portions 242 respectively cover the opposite side surfaces of the electrode assembly 23.

[0113] A second bending crease 24c is provided between the second insulating portion 242 and the third insulating portion 243. Exemplarily, a third insulating portion 243 is provided on each opposite side of the second insulating portion 242. Therefore, a second bending crease 24c is provided between each of the two third insulating portions 243 and the second insulating portion 242. Thus, the two third insulating portions 243 located on opposite sides of the second insulating portion 242 can be folded around their respective second bending creases 24c, so that the two second insulating portions 242 respectively cover the other opposite side surfaces of the electrode assembly 23. Therefore, the second insulating portion 242 and the third insulating portion 243 can provide wrapping protection to the peripheral surface of the electrode assembly 23.

[0114] Optionally, the first fold 24b and the second fold 24c may intersect; exemplaryly, in some embodiments, the first fold 24b is perpendicular to the second fold 24c.

[0115] For example, in some embodiments, the first insulating portion 241, the second insulating portion 242, and the third insulating portion 243 are all rectangular film structures. After the second insulating portion 242 is folded 90 degrees around the first bending crease 24b and the third insulating portion 243 is folded 90 degrees around the second bending crease 24c, the first insulating portion 241, the second insulating portion 242, and the third insulating portion 243 can be assembled to form a rectangular block structure with one end open. Thus, the first insulating portion 241, the second insulating portion 242, and the third insulating portion 243 can provide better wrapping protection for the electrode assembly 23.

[0116] A fold crease 24a is also provided between the first insulating part 241 and the second insulating part 242; it should be understood that the fold crease 24a may be provided parallel to the first bending crease 24b.

[0117] Optionally, the fold crease 24a can be provided on the side of the first bending crease 24b close to the first insulating part 241. In this case, the fold 25 formed with the assistance of the fold crease 24a will be located on the first insulating part 241, that is, the fold 25 is formed between the electrode assembly 23 and the first wall 221.

[0118] Alternatively, the fold crease 24a can be provided on the side of the first bending crease 24b near the second insulating portion 242. In this case, the fold 25 formed with the assistance of the fold crease 24a will be located on the second insulating portion 242, that is, the fold 25 is formed between the electrode assembly 23 and the second wall 222 of the housing.

[0119] Alternatively, fold creases 24a can be provided on both sides of the first fold crease 24b.

[0120] For example, in some embodiments, a fold crease 24a is provided on the side of the first bending crease 24b near the second insulating portion 242, and the number of fold creases 24a formed on a second insulating portion 242 is two; thereby, a fold portion 25 can be formed on the second insulating portion 242, and the two fold creases 24a can assist in folding to form a "U"-shaped fold portion 25.

[0121] With this configuration, the second insulating part 242 can be folded around the first bending crease 24b, and the third insulating part 243 can be folded around the second bending crease 24c, so that the first insulating part 241, the second insulating part 242 and the third insulating part 243 respectively cover different sides of the electrode assembly 23; and the folding crease 24a can help form the folded part 25.

[0122] Please refer to Figures 6 to 8 In some embodiments, the fold 25 has an unfolded length w; wherein 0.5mm ≤ w ≤ 10mm.

[0123] Understandably, the unfolded length w of the fold 25 refers to the length of the fold 25 after it is unfolded to form a planar structure, which is the distance between the two outermost creases among the creases used to form the fold 25.

[0124] For example, when the fold crease 24a is located on either side of the first bending crease 24b and is parallel to the first bending crease 24b, the unfolded length w of the folded portion 25 is the distance between the two outermost fold creases 24a among the plurality of fold creases 24a.

[0125] Alternatively, when the fold crease 24a is located on either side of the first bending crease 24b and parallel to the first bending crease 24b, and the first bending crease 24b is also used to form the fold 25 (i.e., the fold 25 is formed on the insulating member 24 between the electrode assembly 23 and the second wall 222 and faces the first wall 221), such as... Figure 7 The fold shown and Figure 8 (As shown in the unfolded insulating part), at this time the unfolded length w of the folded part 25 is the distance between the first bending crease 24b and the farthest fold crease 24a.

[0126] With this configuration, the unfolded length w of the folded portion 25 is limited to greater than or equal to 0.5 mm (hereinafter referred to as mm) and less than or equal to 10 mm. As a result, the electrode assembly 23 expands so that the folded portion 25 can unfold to a length of 0.5 mm to 10 mm, thereby reducing the pulling effect of the expansion of the electrode assembly 23 on the insulating member 24.

[0127] Please refer to Figures 6 to 8 In some embodiments, 1mm≤w≤6mm.

[0128] With this configuration, the unfolded length w of the folded portion 25 is further limited to greater than or equal to 1 mm and less than or equal to 6 mm. The electrode assembly expands so that the folded portion 25 can unfold to a length of 1 mm to 6 mm, thereby reducing the pulling effect of the expansion of the electrode assembly 23 on the insulating member 24.

[0129] Please refer to Figure 4 , Figures 6 to 8 In some embodiments, the thickness of the electrode assembly 23 is a, 10mm≤a≤80mm; the expansion rate of the electrode assembly 23 is k, 5%≤a≤45%; the folded portion 25 has an unfolded length w, wherein 0.25mm≤w≤18mm.

[0130] The thickness of the electrode assembly 23 refers to the distance between its two planar surfaces. It should be understood that the electrode assembly 23 is a wound body formed by winding a positive electrode, a negative electrode, and a separator; therefore, the electrode assembly 23 includes a flat portion 231 with a planar surface and bent portions 232 disposed at opposite ends of the flat portion 231 with arc-shaped surfaces. The distance between the opposite two planes of the flat portion 231 is the thickness of the electrode assembly 23.

[0131] Understandably, in this embodiment, the thickness a of the electrode assembly 23 is limited to greater than or equal to 10 mm and less than or equal to 80 mm.

[0132] Meanwhile, the expansion rate k of the electrode assembly 23 is limited to greater than or equal to 5% and less than or equal to 45%. The expansion rate k of the electrode assembly 23 is affected by the material of the electrode sheet; for example, the higher the silicon content of the positive electrode sheet, the higher the expansion rate k of the electrode assembly 23.

[0133] Therefore, by limiting the unfolded length of the folded portion 25 to greater than or equal to 0.25 mm and less than or equal to 18 mm, the requirements for the size variation of the insulating member 24 can be met within the thickness range and expansion rate range of the electrode assembly 23.

[0134] With this configuration, when the thickness a of the electrode assembly 23 is in the range of 10 mm to 80 mm and the expansion rate k of the electrode assembly 23 is in the range of 5% to 45%, the unfolded length w of the folded portion 25 can be limited to greater than or equal to 0.25 mm and less than or equal to 18 mm. This allows the insulating member 24 to provide better wrapping protection for the electrode assembly 23 when the folded portion 25 is not unfolded, and the unfolded folded portion 25 can meet the expansion requirements of the electrode assembly 23 after the electrode assembly 23 expands, so that the insulating member 24 can still provide better wrapping protection for the electrode assembly 23.

[0135] Please refer to Figure 4 , Figures 6 to 8 In some embodiments, 1mm ≤ w ≤ 10mm.

[0136] With this configuration, the unfolded length w of the fold 25 is further limited to greater than or equal to 1 mm and less than or equal to 10 mm, so that the insulating member 24 can provide better wrapping protection for the electrode assembly 23 before and after expansion.

[0137] The battery cell 20 provided in this application will now be further described according to specific embodiments.

[0138] Please refer to Figures 3 to 8 In this embodiment, the battery cell 20 includes a housing 210, an electrode assembly 23, and an insulating member 24. The housing 210 includes a shell 22 and an end cap 21. The shell 22 forms a receiving cavity 22a. The end cap 21 is connected to the shell 22 and seals the receiving cavity 22a. The electrode assembly 23 is housed in the receiving cavity 22a. The insulating member 24 is housed in the receiving cavity 22a and is disposed between the electrode assembly 23 and the shell 22.

[0139] The insulating member 24 includes a first insulating portion 241, two second insulating portions 242 formed at opposite ends of the first insulating portion 241, and third insulating portions 243 formed at opposite ends of the two second insulating portions 242 respectively; a first bending crease 24b and two folding creases 24a are provided between the first insulating portion 241 and each of the second insulating portions 242, and a second bending crease 24c is provided between each of the second insulating portions 242 and the corresponding third insulating portion 243.

[0140] The second insulating part 242 is folded 90 degrees around the first bending crease 24b, and the third insulating part 243 is folded 90 degrees around the second bending crease 24c. The first insulating part 241, the second insulating part 242, and the third insulating part 243 can be assembled to form a rectangular block structure with one end open. At the same time, the folding crease 24a and the first bending crease 24b are used together to assist in folding to form a "U"-shaped folded part 25. This folded part 25 will be located between the electrode assembly 23 and the second wall 222 of the housing 22, and the folded part 25 will be adjacent to the first wall 221 of the housing 22.

[0141] Thus, when the electrode assembly 23 does not expand, the folded portion 25 can provide better wrapping protection for the electrode assembly 23; and when the electrode assembly 23 expands, the electrode assembly 23 applies a force to the insulating member 24, so that the folded portion 25 is pulled open, so that the opened folded portion 25 can meet the size change of the expanded electrode assembly 23, and the insulating member 24 can still provide better wrapping protection for the electrode assembly 23.

[0142] Please refer to Figure 2 , Figure 3 and Figure 7 Secondly, embodiments of this application provide a battery device 100, including a plurality of battery cells 20 as described above.

[0143] The battery device 100 provided in this application embodiment includes the aforementioned battery cell 20. In the aforementioned battery cell 20, the insulating member 24 can meet the wrapping protection requirements of the electrode assembly 23 before and after expansion by providing a folded portion 25. As a result, the battery device 100 has better stability.

[0144] Please refer to Figure 1 and Figure 2 Fifthly, embodiments of this application provide an electrical device, including a battery cell 20 or a battery device 100 as described above, wherein the battery cell 20 or the battery device 100 is used to store or provide electrical energy.

[0145] The electrical device provided in this application embodiment is, for example, the vehicle 1000 described above. The electrical device includes the battery cell 20 or the battery device 100 described above. Therefore, the stability of the electrical device is better.

[0146] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A single battery cell, characterized in that: include The outer shell has an internal cavity. The electrode assembly is housed within the receiving cavity; as well as An insulating element is housed within the receiving cavity. The insulating element is disposed between the electrode assembly and the housing. The insulating element has at least one folded portion, which is at least partially circumferentially disposed around the electrode assembly about the winding direction of the electrode assembly. The housing includes a first wall and a second wall surrounding the first wall, and the folded portion is located between the second wall and the electrode assembly; The insulating component has at least two fold lines.

2. The battery cell according to claim 1, characterized in that: The housing includes an end cap connected to one end of the second wall facing away from the first wall, and the folded portion is located at one end of the insulating member facing the first wall.

3. The battery cell according to claim 2, characterized in that: There is a gap between the electrode assembly and the second wall, and the folded portion abuts against the electrode assembly and the second wall.

4. The battery cell according to claim 1, characterized in that: The housing includes a first wall and a second wall circumferentially disposed around the first wall, and the folded portion is located between the first wall and the electrode assembly.

5. The battery cell according to claim 1, characterized in that: The insulating component includes a first insulating portion, two second insulating portions connected to opposite ends of the first insulating portion, and a third insulating portion connected to opposite ends of the two second insulating portions respectively; a first bending crease and a folding crease are provided between the first insulating portion and the second insulating portions, and a second bending crease is provided between the second insulating portion and the third insulating portion.

6. The battery cell according to any one of claims 1 to 5, characterized in that: The folded portion has an unfolded length w; wherein, 0.5mm ≤ w ≤ 10mm.

7. The battery cell according to claim 6, characterized in that: 1mm≤w≤6mm.

8. The battery cell according to any one of claims 1 to 5, characterized in that: The thickness of the electrode assembly is 'a', where 10mm ≤ a ≤ 80mm; the expansion rate of the electrode assembly is 'k', where 5% ≤ k ≤ 45%. The folded portion has an unfolded length w; wherein, 0.25mm ≤ w ≤ 18mm.

9. The battery cell according to claim 8, characterized in that: 1mm≤w≤10mm.

10. A battery device, characterized in that: It includes multiple battery cells according to any one of claims 1 to 9.

11. An electrical device, characterized in that: Includes a battery cell according to any one of claims 1 to 9 or a battery device according to claim 10, wherein the battery cell or the battery device is used to store or provide electrical energy.

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