Battery cell and battery pack

Abstract

Embodiments of the present disclosure provide a battery cell and a battery pack. The battery cell comprises: a shell having a containing space and an opening communicating with the containing space; a cover arranged at the opening and connected with the shell, the cover having an exhaust hole, and the exhaust hole communicating with the containing space; and an exhaust structure connected with the cover, the exhaust structure having an exhaust passage, the exhaust passage communicating with the exhaust hole, and the exhaust passage having an open state and a closed state; wherein the exhaust structure is configured to be in the open state when the air pressure in the containing space is greater than a preset value, to allow the containing space to communicate with the outside via the exhaust hole and the exhaust passage, thereby exhausting the gas in the containing space; and in the closed state when the air pressure in the containing space is not greater than the preset value, to block the communication between the containing space and the outside.

Description

Technical Field

[0001] The exemplary embodiments disclosed herein generally relate to the field of battery technology, and particularly to a battery cell and battery pack. Background Technology

[0002] In some battery technologies, the battery typically uses a sealed cavity formed by welding the casing and top cover, with the core housed inside. During charge-discharge cycles and storage, internal electrochemical side reactions often continuously generate irreversible gases. As the number of cycles increases, these gases gradually accumulate inside the casing, potentially leading to casing bulging and deformation, reduced weld strength, or even cracking. Under certain operating conditions, a sustained increase in gas pressure may trigger the abnormal opening of the explosion-proof valve, causing battery failure. Summary of the Invention

[0003] In a first aspect of this disclosure, a battery cell is provided. The battery cell includes: a housing having a receiving space and an opening communicating with the receiving space; a cover disposed at the opening and connected to the housing, the cover having a vent hole communicating with the receiving space; and a venting structure connected to the cover, the venting structure having a venting channel communicating with the vent hole, and the venting channel having an open state and a closed state; wherein the venting structure is configured to be in an open state when the gas pressure within the receiving space is greater than a preset value, allowing the receiving space to communicate with the outside via the vent hole and the venting channel, thereby discharging gas from the receiving space; and to be in a closed state when the gas pressure within the receiving space is not greater than the preset value, thereby blocking the communication between the receiving space and the outside.

[0004] In some embodiments, the venting structure includes: a base disposed on the side of the cover away from the receiving space and corresponding to the vent hole, the base having an vent passage and an outlet hole, the vent passage communicating with the outlet hole; a shielding member movably disposed within the vent passage; and an elastic member disposed within the vent passage and abutting against the base and the shielding member, the elastic member being configured to apply a force to the shielding member to cause the shielding member to abut against the vent hole.

[0005] In some embodiments, the diameter of the vent hole is smaller than the orthographic projection size of the shielding member on the plane of the cover.

[0006] In some embodiments, the cover has a groove on the side opposite to the receiving space, and the venting structure is at least partially accommodated in the groove.

[0007] In some embodiments, the cover further includes a limiting portion that protrudes from the bottom surface of the groove in a direction away from the receiving space and is disposed around at least a portion of the edge of the vent.

[0008] In some embodiments, the elastic element includes a spring, one end of which abuts against a blocking element and the other end of which abuts against a base.

[0009] In some embodiments, the elastic member includes an elastic pad disposed on the side of the shield opposite to the receiving space and abutting against the shield and the base.

[0010] In some embodiments, the elastic pad is a porous elastomer.

[0011] In some embodiments, the vent is located on the side of the base away from the receiving space.

[0012] In some embodiments, the base is welded to the cover.

[0013] In some embodiments, the shielding element includes steel balls.

[0014] In some embodiments, the venting structure further includes a hydrophobic membrane covering the vent holes and configured to allow gas to pass through while blocking liquid from passing through.

[0015] In some embodiments, the cover has a length direction and is also provided with an explosion-proof valve; along the length direction, the explosion-proof valve and the exhaust structure are spaced apart.

[0016] In a second aspect of this disclosure, a battery pack is provided. The battery pack includes the battery cells described in the first aspect.

[0017] It should be understood that the content described in this section is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0018] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: Figure 1 A perspective view of a battery cell according to some embodiments of the present disclosure is shown; Figure 2 Disassembly diagrams of battery cells according to some embodiments of this disclosure are shown; Figure 3 A perspective view of a battery cell according to some embodiments of the present disclosure is shown, wherein the venting structure is separated from the cover; Figure 4 It shows Figure 3 A magnified view of point A; Figure 5 Disassembly diagrams of exhaust structures according to some embodiments of this disclosure are shown; Figure 6 Perspective views of battery cells according to other embodiments of this disclosure are shown, wherein the venting structure is separate from the cover; and Figure 7 It shows Figure 6 Enlarged view of point B.

[0019] Explanation of reference numerals in the attached figures: X, length direction; 10. Shell; 11. Receiving space; 12. Opening; 20. Cover; 21. Vent hole; 22. Groove; 23. Limiting part; 30. Exhaust structure; 31. Shielding component; 32. Elastic component; 321. Spring; 322. Elastic pad; 33. Base; 330. Exhaust channel; 331. Vent hole; 34. Hydrophobic membrane; 40. Explosion-proof valve. Detailed Implementation

[0020] Embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0021] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc., may refer to different or the same objects.

[0022] In some batteries, the casing and top cover are welded together to form a sealed housing space, within which the core is placed. During charge-discharge cycles and storage, internal electrochemical side reactions often continuously generate irreversible gases. As the number of cycles increases, the gas gradually accumulates inside the casing, causing the internal pressure to rise continuously. This can lead to bulging and deformation of the casing, and the strength of the casing welds may decrease or even crack under the pressure.

[0023] Under certain operating conditions, when the internal gas pressure of the casing continues to rise, it may trigger the abnormal opening of the explosion-proof valve before reaching its design pressure threshold, thus causing battery failure. Furthermore, in battery packs composed of individual cells, the assembly gaps within the pack are typically limited. The expansion of a single cell can also compress surrounding structural components, causing deformation or damage to internal parts. Therefore, throughout the battery's lifespan, there is still room for improvement in achieving real-time venting of gas from the casing while maintaining the structural integrity of the casing.

[0024] In view of this, the exemplary embodiments of this disclosure provide a battery cell and a battery pack. In the battery cell, an exhaust structure is provided on the cover. The exhaust structure has an exhaust channel. The exhaust channel can be opened to release internal gas when the gas pressure in the containment space is greater than a preset value, and closed to maintain a seal when the gas pressure is not greater than the preset value. In this way, it helps to release the gas accumulated inside the casing in real time throughout the battery's life cycle, thereby reducing the risk of casing bulging and deformation, reduced strength of the casing cover weld, and accidental triggering of the explosion-proof valve.

[0025] The exhaust structure mentioned in this article refers to a structural component installed on the cover to discharge internal gas when the internal air pressure reaches a predetermined condition. For example, a one-way valve assembly consisting of a base, a shield, and an elastic element. However, it is not limited to this; any structure capable of achieving the aforementioned one-way exhaust function based on air pressure conditions is applicable.

[0026] In this document, the exhaust channel refers to a channel space formed inside the base for guiding gas from inside the shell to the outside through exhaust holes. For example, a cavity that runs through the inside of the base. However, this disclosure does not limit the specific form of the exhaust channel.

[0027] The term "blocking component" in this article refers to a movable part installed within the exhaust channel, used to seal the exhaust port and prevent gas from escaping under the action of an elastic element. For example, a steel ball. However, it is not limited to this; any component capable of achieving the aforementioned sealing and opening functions is applicable.

[0028] In this article, the term "elastic component" refers to a part installed within the exhaust channel that applies an elastic force to the shielding component, causing it to abut against the exhaust port. Examples include springs or porous elastic pads. However, this is not a limitation; any component capable of providing the aforementioned elastic support force is applicable.

[0029] In this document, "base" refers to a shell-like structural component disposed on the outer surface of a cover, used to accommodate shielding and elastic components and to form an exhaust channel. For example, a convex metal component welded to the surface of the cover. However, this disclosure is not limited to this, and does not restrict the specific shape or material of the base.

[0030] The following will first describe in detail the overall structural composition, venting structure construction and working principle of the battery cell based on the independent claims, and then provide a description of the corresponding battery pack embodiments.

[0031] Figure 1 A perspective view of a battery cell according to some embodiments of the present disclosure is shown. The following will be combined with... Figure 1 Describe the overall appearance and structure of the battery cell.

[0032] Reference Figure 1 According to some embodiments of this disclosure, a battery cell includes a housing 10, a cover 20, a venting structure 30, and an explosion-proof valve 40. The housing 10 can be a square shell structure or a cylindrical structure, and the cover 20 is disposed on the top of the housing 10. Both the venting structure 30 and the explosion-proof valve 40 are disposed on the cover 20. In some embodiments, the venting structure 30 and the explosion-proof valve 40 are spaced apart along the length direction X of the cover 20. In this way, the venting structure 30 and the explosion-proof valve 40 are separated from each other on the cover 20, which helps them to independently perform their venting and pressure relief functions.

[0033] In some embodiments, the housing 10 may be made of metal, such as aluminum alloy or stainless steel. Alternatively or additionally, the housing 10 may also be made of other materials that meet the requirements for structural strength and corrosion resistance, and this disclosure does not limit this. The cover 20 may also be made of metal and is connected to the housing 10 by welding or other means to form a sealed receiving space 11.

[0034] Figure 2 A disassembled diagram of a battery cell according to some embodiments of the present disclosure is shown. The following will be combined with... Figure 2 The fitting relationship between the shell 10 and the cover 20 is described in detail.

[0035] Reference Figure 2 According to some embodiments of this disclosure, the housing 10 has a receiving space 11 and an opening 12 communicating with the receiving space 11. The receiving space 11 is used to receive battery cell assemblies such as winding cores. A cover 20 is disposed at the opening 12 and connected to the housing 10, thereby forming a closed receiving space 11 together with the housing 10. In some embodiments, the cover 20 may be connected to the housing 10 by welding, screwing, or snap-fitting, etc., and this disclosure does not limit this.

[0036] In some embodiments, such as Figure 2 As shown, the cover 20 has a vent 21. The vent 21 extends through the thickness of the cover 20 and communicates with the receiving space 11. In this way, gas inside the receiving space 11 can reach the outer surface of the cover 20 through the vent 21. The venting structure 30 is connected to the cover 20 and is provided at the position corresponding to the vent 21.

[0037] In some embodiments, such as Figures 1 to 5 As shown, the exhaust structure 30 has an exhaust passage 330 that communicates with the exhaust port 21, and the exhaust passage 330 has an open state and a closed state. The exhaust structure 30 is configured to be in the open state when the gas pressure in the containment space 11 is greater than a preset value, so as to allow the containment space 11 to communicate with the outside through the exhaust port 21 and the exhaust passage 330, thereby discharging the gas in the containment space 11.

[0038] In some embodiments, when the air pressure inside the containment space 11 is not greater than a preset value, the exhaust structure 30 is in a closed state to block the connection between the containment space 11 and the outside. In this way, the exhaust structure 30 can adaptively switch between an open state and a closed state according to the air pressure inside the containment space 11, which helps to release the gas accumulated inside in real time during the battery's life cycle, while maintaining the airtightness of the containment space 11 when the air pressure does not reach the preset value.

[0039] Figure 3 A perspective view of a battery cell according to some embodiments of the present disclosure is shown, wherein the venting structure 30 is separated from the cover 20. Figure 4 It shows Figure 3 A magnified view of point A. The following will combine... Figure 3 and Figure 4 The specific construction of the exhaust structure 30 is described in detail.

[0040] Reference Figure 3 and Figure 4 According to some embodiments of this disclosure, the exhaust structure 30 includes a base 33, a shielding member 31, and an elastic member 32. The base 33 is disposed on the side of the cover 20 opposite to the receiving space 11 and is correspondingly disposed with respect to the exhaust port 21. The base 33 has an exhaust channel 330 and an exhaust hole 331, and the exhaust channel 330 communicates with the exhaust hole 331. Thus, the gas in the receiving space 11 can be discharged to the outside in sequence through the exhaust hole 21, the exhaust channel 330, and the exhaust hole 331.

[0041] In some embodiments, the shielding member 31 is movably disposed within the exhaust passage 330. An elastic member 32 is disposed within the exhaust passage 330 and abuts against the base 33 and the shielding member 31. The elastic member 32 is configured to apply a force to the shielding member 31, causing the shielding member 31 to abut against the exhaust port 21. In this manner, under normal conditions where the air pressure within the accommodating space 11 is not greater than a preset value, the shielding member 31 abuts against the exhaust port 21 under the elastic force of the elastic member 32, thereby blocking the exhaust port 21 and keeping the exhaust passage 330 in a closed state.

[0042] In some embodiments, the opening pressure of the exhaust structure 30 is related to the elastic force applied by the elastic member 32 to the blocking member 31 and the effective pressure-bearing area of ​​the blocking member 31. Specifically, when the pressure exerted by the gas in the accommodating space 11 on the blocking member 31 is greater than the elastic force applied by the elastic member 32 to the blocking member 31, the blocking member 31 moves away from the exhaust port 21, so that the exhaust passage 330 switches from the closed state to the open state.

[0043] In some embodiments, the opening pressure of the venting structure 30 can be set by adjusting the elastic coefficient, pre-compression, free length, and / or number of elastic elements 32, or by adjusting the size of the vent holes 21 and the effective pressure-bearing area of ​​the shielding element 31. For example, using a gauge pressure relative to the external ambient pressure, the opening pressure of the venting structure 30 can be from 5 kPa to 100 kPa. The opening pressure can be from 10 kPa to 50 kPa, for example, 15 kPa, 20 kPa, 25 kPa, 30 kPa, 40 kPa, or any two of the above values. The specific value of the opening pressure can be set according to the casing strength of the battery cell, the allowable pressure of the containment space 11, the electrolyte system, and the expected gas production rate.

[0044] In some embodiments, when the air pressure in the accommodating space 11 is greater than a preset value, the thrust exerted by the air pressure on the blocking member 31 can overcome the elastic force of the elastic member 32, causing the blocking member 31 to move in a direction away from the accommodating space 11, thereby opening the exhaust passage 330. Gas in the accommodating space 11 enters the exhaust passage 330 through the exhaust port 21 and is discharged through the vent port 331. After the gas is discharged, the air pressure in the accommodating space 11 decreases, and the blocking member 31, under the action of the elastic force of the elastic member 32, re-presses against the exhaust port 21, and the exhaust passage 330 returns to the closed state.

[0045] In some embodiments, the diameter of the vent 21 is smaller than the orthographic projection size of the shield 31 on the plane of the cover 20. In this way, the shield 31 can cover the entire opening area of ​​the vent 21 when it abuts against it, which helps to provide a better sealing effect when the vent passage 330 is closed. Those skilled in the art will understand that the specific ratio between the diameter of the vent 21 and the orthographic projection size of the shield 31 can be set according to actual needs, and this disclosure does not impose any limitations on this.

[0046] Reference Figure 4In some embodiments, the cover 20 has a groove 22 on the side opposite to the receiving space 11. The exhaust structure 30 is at least partially accommodated in the groove 22. In this way, the groove 22 can provide installation and positioning space for the exhaust structure 30, which helps to position and fix the exhaust structure 30 on the cover 20, and can reduce the protrusion height of the exhaust structure 30 relative to the surface of the cover 20 to a certain extent.

[0047] In some embodiments, the cover 20 further includes a limiting portion 23. The limiting portion 23 protrudes from the bottom surface of the groove 22 in a direction away from the receiving space 11 and is disposed around at least a portion of the edge of the vent 21. In some embodiments, the limiting portion 23 may be in the form of an annular boss. Thus, the limiting portion 23 can limit the radial movement of the shield 31, which helps the shield 31 to move in a predetermined direction within the vent channel 330 without displacement or detachment.

[0048] In some embodiments, the limiting portion 23 can also constrain the axial displacement of the blocking member 31 in the direction away from the receiving space 11, which helps to prevent the blocking member 31 from disengaging from the exhaust passage 330 or the elastic member 32 from excessive deformation. Additionally or alternatively, the limiting portion 23 may also adopt other protruding structural forms that can achieve the above-mentioned limiting function, and this disclosure does not limit it.

[0049] Figure 5 An anatomical diagram of an exhaust structure 30 according to some embodiments of the present disclosure is shown. The following will be combined with... Figure 5 The components of the exhaust structure 30 are described in further detail.

[0050] Reference Figure 5 In some embodiments, the elastic element 32 includes a spring 321. One end of the spring 321 abuts against the blocking element 31, and the other end of the spring 321 abuts against the base 33. In some embodiments, one end of the spring 321 can be connected to the blocking element 31 by welding or other means, and the other end of the spring 321 can be connected to the inner wall of the base 33 by welding or other means. Additionally or alternatively, the spring 321 can also be connected to the blocking element 31 and the base 33 by snap-fit, adhesive, or interference fit, etc., and this disclosure does not limit this.

[0051] In some embodiments, such as Figure 4 and Figure 5 As shown, after the base 33 is installed on and fixed to the cover 20, the base 33 applies pressure to the shield 31 in the direction of the vent 21 via the spring 321. The elastic restoring force generated by the spring 321 after compression presses the shield 31 against the vent 21, thereby closing the vent passage 330. In this way, the spring 321 can provide a continuous elastic resistance force to the shield 31.

[0052] In some embodiments, the blocking element 31 includes a steel ball. The steel ball has a spherical surface and is capable of forming a line seal or surface seal with the edge of the vent 21. In some embodiments, the blocking element 31 is a steel ball, and one end of the spring 321 can be welded to the steel ball. Alternatively or additionally, the blocking element 31 may also be a ceramic ball, a glass ball, or other components capable of achieving a blocking function. This disclosure does not limit the specific material and shape of the blocking element 31.

[0053] In some embodiments, the vent 331 is located on the side of the base 33 opposite to the receiving space 11. In some embodiments, the vent 331 is located on the top of the base 33. Thus, gas discharged through the exhaust passage 330 can be discharged upward from the top of the base 33 to the external space. Alternatively or additionally, the vent 331 may also be located on the side of the base 33 or at other locations; this disclosure does not limit the specific location of the vent 331.

[0054] In some embodiments, the base 33 is welded to the cover 20. In some embodiments, the base 33 can be fixed in the groove 22 of the cover 20 by laser welding. Thus, the base 33 can form a reliable connection with the cover 20. Alternatively or additionally, the base 33 can also be connected to the cover 20 by means of screwing, riveting, bonding, or snap-fitting, etc., which is not limited in this disclosure.

[0055] Reference Figure 5 In some embodiments, the venting structure 30 further includes a hydrophobic membrane 34. The hydrophobic membrane 34 covers the vent 331 and is configured to allow gas to pass through while blocking liquid from passing through. In some embodiments, the hydrophobic membrane 34 may be attached to the vent 331 using a single-sided adhesive structure. In this way, the hydrophobic membrane 34 can allow internal gas to escape while blocking external moisture, dust, and other foreign matter from entering the internal space of the base 33, and also helps prevent electrolyte from leaking to the outside through the vent 331.

[0056] In some embodiments, the hydrophobic film 34 may have a microporous structure, the pore size of which may be set to allow gas molecules to permeate through while blocking liquid molecules from passing through. Additionally or alternatively, the hydrophobic film 34 may also have corrosion resistance to adapt to the electrochemical environment inside the battery. Those skilled in the art will understand that the specific material and microporous structure parameters of the hydrophobic film 34 can be set according to actual application requirements, and this disclosure does not impose any limitations in this regard.

[0057] In some embodiments, the hydrophobic membrane 34 has a hydrophobic microporous structure, through which gas can pass while liquid is blocked by the hydrophobic surface and capillary pressure. When the liquid pressure difference acting on the hydrophobic membrane 34 is less than its liquid inlet pressure, liquid is difficult to enter the micropores. The hydrophobic membrane 34 can be made of materials such as polytetrafluoroethylene, polyvinylidene fluoride, polypropylene, or polyethylene, with a pore size of 0.01 μm to 20 μm and a porosity of 20% to 95%. The liquid inlet pressure and gas permeability of the hydrophobic membrane 34 can be set according to the opening pressure of the exhaust structure 30, the expected exhaust volume, and the wettability of the electrolyte used, and the hydrophobic membrane 34 can have resistance to electrolyte corrosion.

[0058] Figure 6 A perspective view of a battery cell according to other embodiments of the present disclosure is shown, wherein the venting structure 30 is separated from the cover 20. Figure 7 It shows Figure 6 A magnified view of point B. The following will combine... Figure 6 and Figure 7 Another embodiment of the exhaust structure 30 is described in detail.

[0059] Reference Figure 6 and Figure 7 In some embodiments, the elastic member 32 includes an elastic pad 322. The elastic pad 322 is disposed on the side of the shield 31 opposite to the receiving space 11 and abuts against the shield 31 and the base 33. In this way, the elastic pad 322 can replace the function of the spring 321, providing elastic support between the base 33 and the shield 31, so that the shield 31 abuts against the vent 21 to close the vent passage 330.

[0060] In some embodiments, the elastic pad 322 is a porous elastomer. A porous elastomer can compress and deform under stress and return to its original shape after unloading, exhibiting good reversible deformation capability. In some embodiments, the porous elastomer can be porous rubber. The multiple through-holes inside the porous rubber can serve as gas passageways when the elastic pad 322 is compressed, thereby allowing the discharged gas to flow through the elastic pad 322 towards the vent 331.

[0061] In some embodiments, the elastic pad 322 is an open-cell porous elastomer, such as open-cell porous rubber. The elastic pad 322 has interconnected pores inside, or is provided with air channels that penetrate the elastic pad 322 along the gas flow direction. The elastic pad 322 can be compressed and deformed under stress and return to its original shape after unloading; simultaneously, the discharged gas can pass through the elastic pad 322 via the interconnected pores or through air channels and flow towards the air outlet 331. The porosity, pore size, or size of the through air channels of the elastic pad 322 can be set according to the required air permeability to avoid excessive resistance to gas discharge.

[0062] In some embodiments, when gas generation in the receiving space 11 causes the gas pressure to exceed a preset value, the gas pressure pushes the blocking member 31 upward in a direction away from the receiving space 11, compressing the elastic pad 322. The gas in the receiving space 11 enters the exhaust channel 330 through the exhaust port 21, then flows through multiple through holes inside the elastic pad 322 to the vent port 331, and is discharged to the outside through the hydrophobic membrane 34. The limiting part 23 can constrain the axial displacement of the blocking member 31, helping to prevent the elastic pad 322 from being over-compressed.

[0063] In some embodiments, after the gas is discharged, the gas pressure in the accommodating space 11 decreases to no more than a preset value. The elastic pad 322 extends under its own elastic restoring force, pushing the blocking member 31 back against the exhaust port 21, and the exhaust channel 330 returns to the closed state. Thus, the elastic pad 322 can both provide elastic support to realize the opening and closing control of the exhaust channel 330 and serve as a gas passage medium, which helps to achieve both exhaust and sealing functions.

[0064] Alternatively or additionally, the elastic pad 322 may also be made of other porous elastic materials such as porous silicone or elastic foam. This disclosure does not limit the specific material of the elastic pad 322. Those skilled in the art will understand that any elastic component that can provide elastic support between the shielding member 31 and the base 33 and allow gas to pass through can be used as the elastic pad 322.

[0065] In some embodiments, the cover 20 has a length direction X, and an explosion-proof valve 40 is also provided on the cover 20. Along the length direction X, the explosion-proof valve 40 and the exhaust structure 30 are spaced apart. The explosion-proof valve 40 can be configured to open to achieve emergency pressure relief when the gas pressure within the containment space 11 exceeds the design pressure threshold of the explosion-proof valve 40. The preset value of the exhaust structure 30 can be less than the design pressure threshold of the explosion-proof valve 40. In this way, during normal use, the exhaust structure 30 can discharge the gas accumulated in the containment space 11 in real time at a lower gas pressure, helping to prevent the gas pressure from continuously rising to the point of triggering the opening of the explosion-proof valve 40.

[0066] In some embodiments, the explosion-proof valve 40 and the exhaust structure 30 are spaced apart along the length direction X, so that their installation positions on the cover 20 do not interfere with each other. Alternatively or additionally, the explosion-proof valve 40 and the exhaust structure 30 may also be spaced apart along the width direction of the cover 20, or arranged in other ways on the cover 20. This disclosure does not limit the specific arrangement of the explosion-proof valve 40 and the exhaust structure 30.

[0067] Additionally or alternatively, the housing 10 may be a cylindrical housing, a soft-pack housing, or a housing of other shapes. This disclosure does not limit the specific form of the housing 10. The cover 20 may be a one-piece molded part or may be composed of multiple layers. This disclosure does not limit the specific structural form of the cover 20. In some embodiments, the vent 21 may be a circular hole, a rectangular hole, or a through hole of other shapes. This disclosure does not limit the specific shape of the vent 21.

[0068] Alternatively or additionally, the base 33 can be made of metal, ceramic, or polymer materials. Any structural component capable of withstanding the internal air pressure of the housing and providing space for the shielding member 31 and the elastic member 32 can be used as the base 33. In addition to steel balls, the shielding member 31 can also be a ceramic ball, a hard alloy ball, or other components capable of sealing the exhaust port 21. In addition to springs 321 and elastic pads 322, the elastic member 32 can also be a disc spring, an elastic sheet, or other components capable of providing elastic support. This disclosure does not limit the specific form of the elastic member 32.

[0069] Alternatively or additionally, the hydrophobic membrane 34 may be made of polytetrafluoroethylene membrane, polyvinylidene fluoride membrane, or other membrane materials with hydrophobic and breathable functions. In addition to being adhered by adhesive backing, the hydrophobic membrane 34 may also be fixed to the vent 331 by heat fusion, snap-fit, or other means. This disclosure does not limit the fixing method of the hydrophobic membrane 34.

[0070] Those skilled in the art will understand that the component selection, connection method, and layout of the exhaust structure 30 described in the above embodiments are merely examples and do not constitute a limitation on the technical solutions of this disclosure. In other embodiments, other structures or methods capable of achieving the same function may also be used, and this disclosure does not impose any limitations on them.

[0071] In some embodiments, the aforementioned battery cells can also be part of a battery pack. The battery pack includes the aforementioned battery cells. The battery pack may include one or more of the aforementioned battery cells, and multiple battery cells can be connected in series, parallel, or a combination of series and parallel connections to meet different voltage and capacity requirements.

[0072] In some embodiments, since the battery cells are provided with venting structures 30, the gas accumulated inside the casing 10 can be released in real time throughout the battery's lifespan, which helps reduce the risk of the casing 10 bulging and deforming. In this way, when the internal assembly gaps of the battery pack are limited, the volume stability of the battery cells can be improved, thereby helping to reduce the risk of the battery cells expanding and compressing the surrounding structural components inside the battery pack, and can extend the service life of the battery pack to a certain extent.

[0073] Additionally or alternatively, the battery pack may also include components such as a housing, busbars, and a thermal management system. This disclosure does not limit the specific composition of the battery pack. Those skilled in the art will understand that the venting structure 30 and its optional solutions described in the various embodiments of the battery cells described above can be applied to the embodiments of the battery pack, and this disclosure does not limit them.

[0074] It should be understood that the features described in the above embodiments can be combined with each other in any manner without conflict. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the spirit and scope of this disclosure. All such modifications and variations should fall within the protection scope defined by the appended claims.

Claims

1. A battery cell, characterized in that, include: The housing (10) has a receiving space (11) and an opening (12) communicating with the receiving space (11). A cover (20), disposed at the opening (12) and connected to the housing (10), the cover (20) having a vent (21) communicating with the receiving space (11); and An exhaust structure (30) is connected to the cover (20). The exhaust structure (30) has an exhaust channel (330) that communicates with the exhaust hole (21). The exhaust channel (330) has an open state and a closed state. The exhaust structure (30) is configured to be in the open state when the air pressure in the containment space (11) is greater than a preset value, so as to allow the containment space (11) to communicate with the outside through the exhaust port (21) and the exhaust channel (330) to discharge the gas in the containment space (11); and to be in the closed state when the air pressure in the containment space (11) is not greater than the preset value, so as to block the communication between the containment space (11) and the outside.

2. The battery cell according to claim 1, characterized in that, The exhaust structure (30) includes: The base (33) is disposed on the side of the cover (20) away from the receiving space (11) and is disposed corresponding to the exhaust hole (21). The base (33) has the exhaust channel (330) and the air outlet (331), and the exhaust channel (330) communicates with the air outlet (331). A shield (31) is movably disposed within the exhaust passage (330); and An elastic element (32) is disposed within the exhaust passage (330) and abuts against the base (33) and the shield (31). The elastic element (32) is configured to apply a force to the shield (31) to cause the shield (31) to abut against the exhaust port (21).

3. The battery cell according to claim 2, characterized in that, The diameter of the vent (21) is smaller than the orthographic projection size of the shield (31) on the plane of the cover (20).

4. The battery cell according to claim 2, characterized in that, The cover (20) has a groove (22) on the side opposite to the receiving space (11), and the exhaust structure (30) is at least partially housed in the groove (22).

5. The battery cell according to claim 4, characterized in that, The cover (20) also includes a limiting part (23) which protrudes from the bottom surface of the groove (22) in a direction away from the receiving space (11) and is disposed around at least a portion of the edge of the vent (21).

6. The battery cell according to claim 2, characterized in that, The elastic element (32) includes a spring (321), one end of which abuts against the blocking element (31) and the other end of which abuts against the base (33).

7. The battery cell according to claim 2, characterized in that, The elastic element (32) includes an elastic pad (322) disposed on the side of the shield (31) away from the receiving space (11) and abuts against the shield (31) and the base (33).

8. The battery cell according to claim 7, characterized in that, The elastic pad (322) is a porous elastomer.

9. The battery cell according to claim 2, characterized in that, The vent (331) is located on the side of the base (33) away from the receiving space (11).

10. The battery cell according to claim 2, characterized in that, The base (33) is welded to the cover (20).

11. The battery cell according to claim 2, characterized in that, The shield (31) includes steel balls.

12. The battery cell according to any one of claims 2 to 11, characterized in that, The exhaust structure (30) also includes a hydrophobic membrane (34) that covers the vent (331) and is configured to allow gas to pass through while blocking liquid from passing through.

13. The battery cell according to any one of claims 1 to 11, characterized in that, The cover (20) has a length direction (X), and the cover (20) is also provided with an explosion-proof valve (40). Along the length direction (X), the explosion-proof valve (40) and the exhaust structure (30) are spaced apart.

14. A battery pack, characterized in that, include: The battery cell according to any one of claims 1 to 13.

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