Battery monomer, battery and electric device

Abstract

The utility model discloses a battery monomer, a battery and a power utilization device. The battery monomer (61) comprises an electrode assembly (10), the shell (20) is provided with a containing cavity and an open end (20b) communicated with the containing cavity; the end cover (30) covers the opening end (20b); the current collecting assembly (40) is electrically connected to the electrode assembly (10) and the shell (20), the containing cavity comprises a pressure relief cavity (pr) and an electrical cavity (el), the pressure relief cavity (pr) is located between the current collecting assembly (40) and the end cover (30), and the electrical cavity (el) is configured to contain the electrode assembly (10); wherein the end cover (30) is provided with a pressure relief part (50), at least part of the pressure relief part (50) is arranged on the cavity wall of the pressure relief cavity (pr), and the current collecting assembly (40) is provided with at least one channel communicated with the electrical cavity (el) and the pressure relief cavity (pr).

Description

Technical Field

[0001] The present disclosure relates to the technical field of batteries, and particularly to a battery cell, a battery and an electrical device. Background Art

[0002] Secondary batteries, especially lithium-ion batteries, have the advantages of high voltage, high specific energy, long cycle life, green and pollution-free, wide operating temperature range and small self-discharge, etc. They are widely used in portable electronic devices, energy storage devices and power devices of large new energy electric vehicles, and have great significance for solving human environmental pollution and energy crisis. With the wide application of lithium-ion batteries, the reliability of battery use has become a major concern for producers. Summary of the Utility Model

[0003] In one aspect of the present disclosure, a battery cell is provided, including: an electrode assembly; a housing having a receiving cavity and an open end communicating with the receiving cavity; an end cap covering the open end; a current collecting assembly electrically connected to the electrode assembly and the housing, the receiving cavity including a pressure relief cavity and an electrical cavity, the pressure relief cavity being located between the current collecting assembly and the end cap, and the electrical cavity being configured to receive the electrode assembly; wherein, the end cap has a pressure relief portion, at least a part of the pressure relief portion is disposed on the cavity wall of the pressure relief cavity, and the current collecting assembly has at least one channel communicating the electrical cavity and the pressure relief cavity.

[0004] In this embodiment, the current collecting assembly is electrically connected to both the electrode assembly and the housing to achieve electrical connection between the electrode assembly and the housing, and the pressure relief cavity formed between the current collecting assembly and the end cap having a pressure relief portion can be communicated with the electrical cavity for receiving the electrode assembly through the channel on the current collecting assembly, so that the gas generated in the case of thermal runaway of the electrode assembly can quickly enter the pressure relief cavity, triggering the pressure relief portion disposed on at least a part of the cavity wall of the pressure relief cavity to relieve pressure, thereby reducing the risks of the housing expanding, deforming and cracking due to excessive internal pressure accumulation of the battery cell.

[0005] In some embodiments, the at least one channel includes: a first channel located around the pressure relief cavity.

[0006] In this embodiment, the receiving cavity and the pressure relief cavity are communicated through the first channel provided along the periphery of the pressure relief cavity, and substances such as high-pressure gas generated inside the battery cell can enter the pressure relief cavity through the first channel around the pressure relief cavity, so as to guide the high-pressure gas around the pressure relief cavity to quickly enter the pressure relief cavity and improve the pressure relief efficiency.

[0007] In some embodiments, the at least one channel includes a plurality of the first channels, and the plurality of first channels are arranged at intervals along the periphery of the pressure relief cavity.

[0008] In this embodiment, through a plurality of the first channels arranged at intervals along the periphery of the pressure relief cavity, pressure relief paths can be realized in multiple directions around the pressure relief cavity, thereby improving the pressure relief efficiency of the battery cell and helping to reduce the risk of excessive local pressure inside the battery cell.

[0009] In some embodiments, the plurality of the first channels are arranged at equal intervals along the periphery of the pressure relief cavity.

[0010] In this embodiment, arranging the plurality of first channels at equal intervals along the periphery of the pressure relief cavity enables the high-pressure gas to enter the pressure relief cavity more evenly from the periphery of the pressure relief cavity to achieve pressure relief.

[0011] In some embodiments, the end cap is electrically connected to the housing, and the current collecting assembly includes: a first conductive member welded to the end cap and having a hollow portion penetrating in the thickness direction of the end cap; and a second conductive member electrically connected to the first conductive member and welded to a first tab of the electrode assembly on a side adjacent to the end cap; wherein, the end cap, the hollow portion and the second conductive member enclose the pressure relief cavity, and the first channel is disposed between the first conductive member and the second conductive member and is communicated with the hollow portion.

[0012] In this embodiment, a current collecting assembly with the first conductive member and the second conductive member electrically connected is adopted. The first conductive member is welded to the end cap electrically connected to the housing, and the second conductive member is welded to the first tab of the electrode assembly. In this way, the first conductive member and the second conductive member can be adaptively designed according to the materials of the end cap and the first tab respectively, having better welding compatibility and helping to reduce the welding quality risk caused by the difference in welding performance of materials during welding. The end cap, the hollow portion of the first conductive member and the second conductive member can form a deeper pressure relief cavity, which helps to improve the gas flow in the pressure relief cavity. And through the cooperation of the first channel disposed between the first conductive member and the second conductive member and the hollow portion on the first conductive member, the pressure relief cavity can receive the high-pressure gas in the battery cell more quickly, improving the pressure relief efficiency.

[0013] In some embodiments, the matrix materials of the end cap and the first tab are different; wherein the matrix material of the first conductive member is the same as that of the end cap, and / or the matrix material of the second conductive member is the same as that of the first tab.

[0014] In this embodiment, for the case where there are differences in the base materials of the end cap and the first tab, the base material of the first conductive member can be set to be the same as that of the end cap base material, so that it is easier to obtain good welding quality between the end cap and the first conductive member, which helps to reduce the conductivity between the end cap and the first conductive member and reduce the risk of end cap leakage caused by poor welding quality. And setting the base material of the second conductive member to be the same as that of the first tab helps to reduce the conductivity between the second conductive member and the first tab, thereby reducing the internal resistance of the battery cell.

[0015] In some embodiments, the base materials of the end cap and the first conductive member are both steel, and the base materials of the first tab and the second conductive member are both copper.

[0016] In this embodiment, setting the base materials of the end cap and the first conductive member to be both steel alloy not only helps to improve the welding quality between the two, but also can improve the mechanical properties of the end cap and reduce the material cost. And setting the base materials of the first tab and the second conductive member to be both copper can achieve high conductivity.

[0017] In some embodiments, the electrode assembly is a cylindrical electrode assembly. The second conductive member includes a plate body. The edge region of the plate body is welded to the first conductive member and is provided with a notch, and the notch serves as at least part of the first channel and is exposed in the hollow portion.

[0018] In this embodiment, a notch serving as the first channel is provided in the edge region of the plate body, so that the high-pressure gas generated in the electrical cavity in the case of thermal failure or the like can enter the pressure relief cavity from the position exposed in the hollow portion through the notch from the periphery of the plate body. The edge region of the plate body is welded to the first conductive member, which can not only strengthen the current collector assembly in terms of strength and stiffness, but also has a relatively simple structure, which is beneficial to manufacturing and assembly.

[0019] In some embodiments, a plurality of notches are provided in the edge region of the plate body, and the plurality of notches are arranged at intervals along the circumferential direction of the plate body.

[0020] In this embodiment, a plurality of first channels are formed by a plurality of notches arranged at intervals along the circumferential direction of the plate body, and pressure relief paths can be realized in multiple directions around the pressure relief cavity, thereby improving the pressure relief efficiency of the battery cell and reducing the risk of excessive local pressure.

[0021] In some embodiments, the plurality of notches are arranged at equal intervals along the circumferential direction of the plate body.

[0022] In this embodiment, arranging the plurality of notches at equal intervals along the circumferential direction of the plate body can enable the high-pressure gas to enter the pressure relief cavity more evenly to achieve pressure relief.

[0023] In some embodiments, the at least one channel further includes: a second channel opened at the center of the plate body, and a portion of the plate body between the second channel and the edge region is welded to the first tab.

[0024] In this embodiment, a second channel is opened at the center of the plate body, which communicates the electrical cavity and the pressure relief cavity at the center of the end portion adjacent to the electrode assembly, so as to more conveniently receive the high-pressure gas generated by the electrode assembly. Moreover, a portion of the plate body between the second channel and the edge region is welded to the first tab, which can achieve a larger area of welding with the first tab, helping to reduce the welding difficulty and improve the welding quality.

[0025] In some embodiments, the electrode assembly is a cylindrical electrode assembly, the second conductive member includes a flat plate portion and a convex portion, the convex portion protrudes from the flat plate portion in a direction away from the electrode assembly, and a recessed portion is formed inside. The orthographic projection of the recessed portion on the first conductive member at least partially coincides with the hollow portion, and the convex portion is welded to the first conductive member; the first channel is provided in the convex portion.

[0026] For the battery cell embodiments including a cylindrical electrode assembly, the convex portion can form a support structure with higher strength and stiffness, improving the mechanical properties of the current collector assembly. Moreover, the recessed portion formed inside the convex portion of the second conductive member can cooperate with the hollow portion of the first conductive member to form a deeper pressure relief cavity, which helps to improve the gas flow in the pressure relief cavity; in addition, the welding position between the convex portion and the first conductive member is far from the flat plate portion, which can reduce the influence of the welding here on the welding of the flat plate portion.

[0027] In some embodiments, a first groove recessed from the flat plate portion in a direction away from the electrode assembly is formed on one side of the convex portion adjacent to the electrode assembly, and a third through hole is opened on the inner side wall of the convex portion located between the first groove and the recessed portion. The first groove and the third through hole serve as at least a part of the first channel.

[0028] In this embodiment, a first groove is formed on one side of the convex portion of the second conductive member adjacent to the electrode assembly, so that a gap can be formed between the first groove and the first tab, reducing the risk that the first channel on the second conductive member is blocked by the first tab due to the first tab being in contact. The third through hole is provided on the inner side wall of the convex portion located between the first groove and the recessed portion, and can guide the high-pressure air flow entering the first groove to the inside of the recessed portion.

[0029] In some embodiments, a plurality of the third through holes are opened between the first groove and the recessed portion of the convex portion, and the plurality of third through holes are arranged at intervals along the circumferential direction of the second conductive member.

[0030] In this embodiment, a plurality of third through holes arranged at intervals along the circumferential direction of the second conductive member between the first groove and the recess cooperate with the first groove to form a plurality of first channels, so that pressure relief paths can be realized in multiple directions around the pressure relief cavity, thereby improving the pressure relief efficiency of the battery cell and reducing the risk of excessive local pressure.

[0031] In some embodiments, the plurality of third through holes are arranged at equal intervals along the circumferential direction of the second conductive member.

[0032] In this embodiment, arranging the plurality of third through holes at equal intervals along the circumferential direction of the second conductive member enables the high-pressure gas to enter the pressure relief cavity more evenly to achieve pressure relief.

[0033] In some embodiments, a protruding edge also extends outward from the outer side of the convex portion.

[0034] In this embodiment, a protruding edge extends from the outer side of the convex portion. The protruding edge can increase the extrusion surface area between the bent edge of the convex portion and the tab, reducing the risk of the tab being damaged due to excessive pressure.

[0035] In some embodiments, the end face of the protruding edge adjacent to the electrode assembly side is flush with the end face of the flat portion adjacent to the electrode assembly side.

[0036] In this embodiment, by making the end face of the protruding edge on the side adjacent to the electrode assembly flush with the end face of the flat portion, the extrusion surface area between the bent edge of the convex portion and the tab can be further increased.

[0037] In some embodiments, the first conductive member is in a circular ring shape, the outer ring radius of the first conductive member is greater than the maximum distance from the outer side wall of the convex portion to the center of the recess, the first conductive member, the protruding edge and the convex portion jointly enclose a second groove located outside the convex portion, the outer side wall of the convex portion is arranged between the second groove and the first groove, and a fourth through hole is provided, and the second groove, the first groove, the fourth through hole and the third through hole serve as at least a part of the first channel.

[0038] In this embodiment, the outer ring radius of the first conductive member is greater than the maximum distance from the outer side wall of the convex portion to the center of the recess, so that a second groove can be formed after the first conductive member and the convex portion are welded. The fourth through hole provided on the outer side wall of the convex portion between the second groove and the first groove can guide the high-pressure gas outside the current collector assembly, so that the high-pressure gas enters the inner side of the recess through the fourth through hole, the first groove and the third through hole.

[0039] In some embodiments, a plurality of the fourth through-holes are formed in an outer sidewall of the convex portion between the second groove and the first groove, and a plurality of the third through-holes are formed between the first groove and the recessed portion. The plurality of the third through-holes and the plurality of the fourth through-holes are arranged at intervals along a circumferential direction of the second conductive member, and at least a part of the plurality of the third through-holes and the plurality of the fourth through-holes are aligned or staggered in a radial direction.

[0040] In this embodiment, by arranging the plurality of the fourth through-holes and the plurality of the third through-holes at equal intervals along the circumferential direction of the second conductive member, and making at least a part of the plurality of the third through-holes and the plurality of the fourth through-holes aligned or staggered in the radial direction, high-pressure gases in different directions of the flow guiding assembly can enter the pressure relief chamber more uniformly to achieve pressure relief.

[0041] In some embodiments, the convex portion is annular and forms an annular first groove.

[0042] In this embodiment, by making the convex portion annular, a recessed portion with continuous side edges can be surrounded to cooperate with the hollow portion of the first conductive member to form a pressure relief chamber. Moreover, the annular convex portion forming the annular first groove can achieve circumferential rectification and flow guiding effects on high-pressure airflows at different circumferential positions, thereby improving the consistency of the pressure relief speed caused by the internal gas pressure difference of the battery cell, and further improving the pressure relief efficiency.

[0043] In some embodiments, the convex portion is annular and together with the first conductive member and the protruding edge surrounds an annular second groove.

[0044] In this embodiment, by making the convex portion annular, a recessed portion with continuous side edges can be surrounded to cooperate with the hollow portion of the first conductive member to form a pressure relief chamber. Moreover, the annular convex portion together with the first conductive member and the protruding edge surrounding the annular second groove can achieve circumferential rectification and flow guiding effects on high-pressure airflows at different circumferential positions on the outside, thereby improving the consistency of the pressure relief speed caused by the internal gas pressure difference of the battery cell, and further improving the pressure relief efficiency.

[0045] In some embodiments, the at least one channel further includes: a second channel formed in a center of the flat portion, and a part of the flat portion outside the second channel is welded to the first tab.

[0046] In this embodiment, the second channel is formed in the center of the flat portion, and the electrical cavity and the pressure relief chamber are communicated at the center of the end adjacent to the electrode assembly, so as to more conveniently receive high-pressure gases generated by the electrode assembly. Moreover, a part of the flat portion outside the second channel is welded to the first tab, which can achieve a larger-area welding with the first tab, helping to reduce the welding difficulty and improve the welding quality.

[0047] In some embodiments, a first portion of the end cap that defines the pressure relief cavity protrudes in a direction away from the electrode assembly relative to a second portion of the end cap where the first conductive member is welded.

[0048] In this embodiment, a first portion of the end cap that defines the pressure relief cavity protrudes in a direction away from the electrode assembly relative to a second portion of the end cap where the first conductive member is welded. A side wall of the first portion adjacent to the electrode assembly can cooperate with a hollow portion of the first conductive member and the second conductive member to define a relatively deep pressure relief cavity, which is beneficial to the gas flow inside the pressure relief cavity. The second portion is fixedly connected to the first conductive member, enabling the end cap to be reliably fixed to the current collector assembly inside the housing.

[0049] In some embodiments, the housing includes a side wall that defines the open end and a bottom wall connected to the side wall and opposite to the open end. An electrode terminal is provided on the bottom wall. The electrode assembly includes a main body portion, a first tab and a second tab with opposite polarities. The first tab is disposed at an end of the main body portion adjacent to the end cap and is electrically connected to the current collector assembly. The second tab is disposed at an end of the main body portion adjacent to the bottom wall and is electrically connected to the electrode terminal.

[0050] In this embodiment, the first tab and the second tab of the electrode assembly have opposite polarities and are respectively disposed on one side of the main body portion adjacent to the end cap and on one side adjacent to the bottom wall of the housing. In this way, the second tab can be directly or through the current collector assembly electrically connected to the electrode terminal provided on the bottom wall, so as to realize the charge and discharge functions of the battery cell through the electrical connection between the electrode terminal and an external conductor.

[0051] In some embodiments, the bottom wall and the side wall are an integrally formed structure.

[0052] In this embodiment, by making the bottom wall and the side wall an integrally formed structure, the overall sealing performance of the housing can be improved, which is beneficial to simplifying the processing and assembly processes.

[0053] In one aspect of the present disclosure, a battery is provided, including: the aforementioned battery cell.

[0054] The battery using the battery cell of the foregoing embodiment has good reliability.

[0055] In one aspect of the present disclosure, an electrical device is provided, including: the aforementioned battery.

[0056] The electrical device using the battery of the foregoing embodiment has good reliability. Description of the Drawings

[0057] The accompanying drawings described herein are used to provide a further understanding of the present disclosure, and constitute a part of this application. The schematic embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation to the present disclosure. In the drawings:

[0058] Figure 1 is a schematic structural diagram of some embodiments of an electrical device according to the present disclosure;

[0059] Figure 2 is a schematic structural diagram of some embodiments of a battery according to the present disclosure;

[0060] Figure 3 is a schematic structural diagram of some embodiments of a battery cell according to the present disclosure;

[0061] Figure 4 is an exploded structural diagram of some embodiments of a battery cell according to the present disclosure;

[0062] Figure 5 is a schematic installation structure diagram of a housing, an end cap, and a current collector assembly in some embodiments of a battery cell according to the present disclosure;

[0063] Figure 6A is a schematic structural diagram of a current collector assembly in some embodiments of a battery cell according to the present disclosure;

[0064] Figure 6B is Figure 6A a schematic structural diagram of a first conductive member in the illustrated embodiment;

[0065] Figure 6C is Figure 6A a schematic structural diagram of a second conductive member in the illustrated embodiment;

[0066] Figure 6D is Figure 6A a cross-sectional schematic diagram of the installation structure of an end cap, a current collector assembly, and an electrode assembly in the illustrated embodiment;

[0067] Figure 7A is a schematic structural diagram of a current collector assembly in some other embodiments of a battery cell according to the present disclosure;

[0068] Figure 7B is Figure 7A a schematic structural diagram of a first conductive member in the illustrated embodiment;

[0069] Figure 7C is Figure 7A a schematic structural diagram of a second conductive member in the illustrated embodiment;

[0070] Figure 7D is Figure 7A a cross-sectional schematic diagram of the installation structure of an end cap, a current collector assembly, and an electrode assembly in the illustrated embodiment;

[0071] Figure 7E is Figure 7D an enlarged schematic view of the selected area of the dashed ellipse A in

[0072] Figure 7F is Figure 7E a dimensional schematic view of the current collector assembly in

[0073] Each reference numeral represents: 10 - electrode assembly; 11 - main body portion; 12 - first tab; 13 - second tab; 14 - central hole;

[0074] 20 - housing; 20b - open end; 21 - side wall; 22 - bottom wall; 221 - electrode terminal;

[0075] 30 - end cap; 31 - first part; 32 - second part;

[0076] 40, 40’ - current collector assembly; 4A - first channel; 4B - second channel; 41 - first conductive member; 41a - main body portion; 42 - second conductive member; 421 - first welding portion; 422 - second welding portion; 42a - plate body; 42b - notch; 42d - flat portion; 42e - convex portion; 42g - recessed portion; 42h - first groove; 42i - third through hole; 42j - flange; 42k - second groove; 42l - fourth through hole;

[0077] 50 - pressure relief portion;

[0078] 60 - battery; 61 - battery cell; 62 - box body; 63 - box cover;

[0079] 70 - vehicle;

[0080] pr - pressure relief cavity; el - electrical cavity; dr1 - first direction; dr2 - second direction; dr3 - third direction. Detailed implementation manners

[0081] The following further describes the implementation manners of the present disclosure in detail with reference to the drawings and embodiments. The following detailed description of the embodiments and the drawings are used to exemplarily illustrate the principle of the present disclosure, but cannot be used to limit the scope of the present disclosure, that is, the present disclosure is not limited to the described embodiments.

[0082] In the description of the present disclosure, it should be noted that unless otherwise specified, "a plurality of" means more than two; the orientation or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation on the present disclosure. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. "Vertical" does not mean strictly vertical, but within the allowable error range. "Parallel" does not mean strictly parallel, but within the allowable error range.

[0083] The orientation words appearing in the following description are all the directions shown in the figures, and do not limit the specific structure of the present disclosure. In the description of the present disclosure, it should also be noted that unless otherwise clearly specified and limited, the terms "mounted", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0084] The following will describe in detail some embodiments of the present disclosure with reference to the accompanying drawings. Without conflict, the features in the following embodiments can be combined with each other.

[0085] "A plurality of" as used in the present disclosure means more than two (including two).

[0086] In the embodiments of the present disclosure, the battery cell can be a secondary battery, which refers to a battery cell that can activate the active material and continue to be used by charging after discharging the battery cell.

[0087] The battery cell can be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium-metal battery, a sodium-metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of the present application are not limited thereto.

[0088] In some related technologies, the current collector plate and the end cap are welded to form a whole circular weld, so that a sealed space other than the central hole is formed between the current collector plate and the end cap provided with the pressure relief component, and a central hole is provided on the current collector plate to receive the high-pressure gas and active substances generated by the electrode assembly in the case of thermal runaway, etc. into the pressure relief cavity to trigger the pressure relief component to achieve pressure relief.

[0089] It has been found through research that the pressure relief cavity formed by this structure is relatively thin, and the gas flow in the cavity is not smooth. When thermal runaway or other situations occur, the high-pressure gas and active substances generated are difficult to quickly enter the pressure relief cavity from the central hole to trigger the pressure relief component, which may cause the risk of excessive internal pressure in the battery cell due to untimely pressure relief of the pressure relief component, bringing adverse factors to the stable and reliable use of the battery cell.

[0090] In view of this, the embodiments of the present disclosure provide a battery cell, a battery, and an electrical device, which can improve reliability.

[0091] In one aspect of the present disclosure, a battery cell is provided, including:

[0092] An electrode assembly;

[0093] A housing having a receiving cavity and an open end communicating with the receiving cavity;

[0094] An end cap covering the open end;

[0095] A current collector assembly electrically connected to the electrode assembly and the housing, the receiving cavity including a pressure relief cavity and an electrical cavity, the pressure relief cavity being located between the current collector assembly and the end cap, and the electrical cavity being configured to receive the electrode assembly;

[0096] Wherein, the end cap has a pressure relief portion, at least a part of the pressure relief portion is provided on the cavity wall of the pressure relief cavity, and the current collector assembly has at least one channel communicating the electrical cavity and the pressure relief cavity.

[0097] In this embodiment, the current collector assembly is electrically connected to both the electrode assembly and the housing to achieve electrical connection between the electrode assembly and the housing, and the pressure relief cavity formed between the current collector assembly and the end cap with a pressure relief portion can be communicated with the electrical cavity accommodating the electrode assembly through the channel on the current collector assembly, so that the gas generated in the case of thermal runaway or the like of the electrode assembly can quickly enter the pressure relief cavity to trigger the pressure relief portion provided at least partially on the cavity wall of the pressure relief cavity to relieve pressure, thereby reducing the risks such as the housing expanding, deforming, and cracking due to excessive internal pressure accumulation in the battery cell.

[0098] The battery cell of the embodiments of the present disclosure can be applied to various types of batteries. The battery mentioned here refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0099] In some embodiments, the battery may include a box body and a battery module. The box body is used to provide a receiving space for the battery module, and the battery module is installed in the box body. The box body can be made of a metal material. The battery module can include a plurality of battery cells connected in series, parallel, or in a hybrid connection. The battery cell is the smallest unit that makes up the battery. The battery cell includes an electrode assembly capable of undergoing an electrochemical reaction.

[0100] In some embodiments, the battery may include a battery box and battery cells, and the battery cells are accommodated in the battery box.

[0101] In some embodiments, the battery box may be part of the chassis structure of a vehicle. For example, part of the battery box may form at least part of the floor of the vehicle, or part of the battery box may form at least part of the cross beams and longitudinal beams of the vehicle.

[0102] In some embodiments, the battery may be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0103] The battery according to the embodiments of the present disclosure is applicable to various electrical devices that use batteries. The electrical devices may be mobile phones, portable devices, laptop computers, battery-powered vehicles, electric vehicles, ships, spacecrafts, electric toys, and electric tools, etc. For example, spacecrafts include airplanes, rockets, space shuttles, and spaceships, etc., electric toys include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, etc., and electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact electric drills, concrete vibrators, and electric planers. The embodiments of the present disclosure do not particularly limit the above-mentioned electrical devices. The battery can be used to supply power to electrical devices such as vehicles, for example, to provide power for vehicle control or driving.

[0104] Figure 1 FIG. is a schematic structural diagram of some embodiments of an electrical device according to the present disclosure. For convenience, the electrical device is taken as an example of a vehicle for illustration. The vehicle 70 may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle or a hybrid electric vehicle, etc. A battery 60 may be disposed at the bottom, the front end, or the rear end of the vehicle 70.

[0105] The battery 60 can be used to supply power to the vehicle 70. For example, the battery 60 can be used as the operating power source of the vehicle 70 for the electrical system of the vehicle 70, such as for the power consumption requirements during the start, navigation, and operation of the vehicle 70. The battery 60 can not only be used as the operating power source of the vehicle 70, but also be used as the driving power source of the vehicle 70 to replace or partially replace fuel or natural gas to provide driving force for the vehicle 70.

[0106] An axle, wheels, a motor 72, and a controller 71 may also be disposed inside the vehicle 70, and the controller is used to control the power supply of the battery 60 to the motor 72. For example, when the vehicle 70 uses the battery 60 as the driving power source, the battery 60 replaces or partially replaces fuel or natural gas to provide the power required for the motor 72 to run at a constant speed or accelerate. The motor 72 is used to drive the axle to rotate, so as to drive the wheels to rotate.

[0107] Figure 2 A structural schematic diagram of some embodiments of the battery according to the present disclosure. Refer to Figure 2 , in some embodiments, the battery 60 includes a box body 62, a box cover 63 covering the opening side of the box body 62, and one or more battery cells 61 disposed in the box body 62. To facilitate the display of the battery cells 61 inside the box body 62, Figure 2 part of the box cover 63 is hidden in

[0108] . The box body 62 and the box cover 63 can provide an accommodation space for the battery cells 61, and provide functions such as cooling, sealing, and anti-impact, and can also avoid the adverse effects of liquids or other foreign objects on the charge and discharge or safety of the battery cells.

[0109] Figure 2 The battery cells 61 in

[0110] are electrically connected to each other, such as in series, parallel, or a combination of series and parallel, to achieve the required electrical performance parameters of the battery 60. A combination of series and parallel means that there are both series and parallel connections among multiple battery cells 61. Adjacent battery cells 61 can be electrically connected through a bus bar. Multiple battery cells 61 are arranged in rows, and one row or multiple rows of battery cells 61 can be arranged in the box body 62 as needed.

[0111] In some embodiments, multiple battery cells 61 can be first connected in series, parallel, or a combination of series and parallel to form a battery module, and then multiple battery modules are connected in series, parallel, or a combination of series and parallel to form a whole and are accommodated in the box body 62. In other embodiments, all battery cells 61 are directly connected in series, parallel, or a combination of series and parallel together, and then the whole formed by all battery cells 61 is accommodated in the box body.

[0112] Figure 3 A structural schematic diagram of some embodiments of the battery cell according to the present disclosure. Figure 4 An exploded structural schematic diagram of some embodiments of the battery cell according to the present disclosure. Figure 5Schematic diagram of the installation structure of the housing, end cap and current collector assembly in some embodiments of the battery cell according to the present disclosure.

[0113] Referring Figures 3 - 5 , embodiments of the present disclosure provide a battery cell 61, including: an electrode assembly 10, a housing 20, an end cap 30, and a current collector assembly 40. The housing 20 has a receiving cavity for receiving the electrode assembly 10 and an open end 20b communicating with the receiving cavity. The end cap 30 covers the open end 20b. The current collector assembly 40 is electrically connected to the electrode assembly 10 and the housing 20. The receiving cavity includes a pressure relief cavity pr and an electrical cavity el. The pressure relief cavity pr is located between the current collector assembly 40 and the end cap 30. The electrical cavity el is configured to receive the electrode assembly 10. The end cap 30 has a pressure relief portion 50, at least a part of the pressure relief portion 50 is provided on the cavity wall of the pressure relief cavity pr, and the current collector assembly 40 has at least one channel communicating the electrical cavity el and the pressure relief cavity pr.

[0114] In this embodiment, the current collector assembly is electrically connected to both the electrode assembly and the housing to achieve electrical connection between the electrode assembly and the housing. The pressure relief cavity formed between the current collector assembly and the end cap with a pressure relief portion can be communicated with the electrical cavity containing the electrode assembly through the channels on the current collector assembly. Thus, the gas generated in the case of thermal runaway of the electrode assembly can quickly enter the pressure relief cavity, triggering the pressure relief portion provided at least partially on the cavity wall of the pressure relief cavity to relieve pressure, thereby reducing the risks such as the expansion deformation and rupture of the housing caused by excessive internal pressure accumulation of the battery cell.

[0115] The electrode assembly 10 may include a first electrode tab and a second electrode tab with opposite polarities, and further includes a separator disposed between the first electrode tab and the second electrode tab. In some embodiments, the first electrode tab is a positive electrode tab and the second electrode tab is a negative electrode tab. In other embodiments, the first electrode tab is a negative electrode tab and the second electrode tab is a positive electrode tab. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and extracted back and forth between the positive electrode tab and the negative electrode tab. The separator is disposed between the positive electrode tab and the negative electrode tab, which can play a role in preventing short circuit between the positive and negative electrodes and allowing active ions to pass through at the same time.

[0116] In some embodiments, the positive electrode tab may include a positive electrode current collector substrate and a positive electrode active material layer provided on at least one surface of the positive electrode current collector substrate.

[0117] As an example, the positive electrode current collector substrate has two surfaces opposite to each other in its own thickness direction, and the positive electrode active material layer is provided on any one or both of the two opposite surfaces of the positive electrode current collector substrate.

[0118] As an example, the positive electrode current collector substrate can be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. can be used. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by depositing a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as substrates of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0119] As an example, the positive electrode active material layer can include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present disclosure is not limited to these materials, and other conventional materials that can be used as the battery positive electrode active material layer can also be used. These positive electrode active material layers can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates can include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (which can also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite material of lithium manganese iron phosphate and carbon, etc. Examples of lithium transition metal oxides can include, but are not limited to, lithium cobalt oxide (such as LiCoO 2 ), lithium nickel oxide (such as LiNiO 2 ), lithium manganese oxide (such as LiMnO 2 , LiMn 2 O 4 ), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 (which can also be abbreviated as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (which can also be abbreviated as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (which can also be abbreviated as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (which can also be abbreviated as NCM 622 ), LiNi 0.8Co 0.1 Mn 0.1 O 2 (which can also be abbreviated as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O 2 ), and at least one of its modified compounds, etc.

[0120] In some embodiments, the negative electrode tab can include a negative electrode current collector substrate.

[0121] As an example, the negative electrode current collector substrate can be a metal foil, a foam metal, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, titanium, etc. can be used. The foam metal can be foam nickel, foam copper, foam aluminum, foam alloy, or foam carbon, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by depositing a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0122] In some embodiments, the negative electrode tab can include a negative electrode current collector substrate and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector substrate.

[0123] As an example, the negative electrode current collector substrate has two surfaces opposite to each other in its own thickness direction, and the negative electrode active material layer is disposed on either one or both of the two opposite surfaces of the negative electrode current collector substrate.

[0124] As an example, the negative electrode active material layer can use the negative electrode active material layer for battery monomers known in the art. As an example, the negative electrode active material layer can include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based materials can be selected from at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based materials can be selected from at least one of elemental tin, tin oxides, and tin alloys. However, the present disclosure is not limited to these materials, and other conventional materials that can be used as the battery negative electrode active material layer can also be used. These negative electrode active material layers can be used alone or in combination of two or more.

[0125] In some embodiments, the material of the positive electrode current collector substrate can be aluminum, and the material of the negative electrode current collector substrate can be copper.

[0126] In some embodiments, the separator is a separator membrane. The present disclosure does not particularly limit the type of the separator membrane, and any well-known porous structure separator membrane with good chemical stability and mechanical stability can be selected.

[0127] As an example, the main material of the separator membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. The separator membrane can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator membrane is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a single component located between the positive electrode plate and the negative electrode plate, or can be attached to the surface of the positive electrode plate and / or the surface of the negative electrode plate while being located between the positive electrode plate and the negative electrode plate.

[0128] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive electrode plate and the negative electrode plate, and simultaneously functions to transport ions and isolate the positive and negative electrodes.

[0129] In some embodiments, the battery cell further includes an electrolyte, and the electrolyte functions to conduct ions between the positive and negative electrodes. The present disclosure does not specifically limit the type of the electrolyte, and it can be selected according to requirements. The electrolyte can be liquid, gel-like, or solid.

[0130] As an example, the liquid electrolyte includes an electrolyte salt and a solvent.

[0131] In some embodiments, the electrolyte salt can be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium bis(oxalate) borate, lithium difluoro bis(oxalate) phosphate, and lithium tetrafluorooxalate phosphate.

[0132] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be an ether solvent. The ether solvent can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether.

[0133] As an example, the gel-like electrolyte includes a polymer as the skeleton network of the electrolyte, combined with an ionic liquid-lithium salt.

[0134] As an example, the solid electrolyte includes a polymer solid electrolyte, an inorganic solid electrolyte, and a composite solid electrolyte.

[0135] As an example, the polymer solid electrolyte can be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single-ion polymer, polyionic liquid-lithium salt, cellulose, etc.

[0136] As an example, the inorganic solid electrolyte can be one or more of an oxide solid electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorus sulfur, argyrodite), amorphous sulfide), and a halide solid electrolyte, a nitride solid electrolyte, and a hydride solid electrolyte.

[0137] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0138] In some embodiments, the electrode assembly includes a main body 11. The main body 11 can be a main body of a wound structure formed by winding a positive electrode plate, a negative electrode plate, and a separator, or a main body of a stacked structure formed by overlapping a positive electrode plate, a negative electrode plate, and a separator. One or more positive electrode plates and negative electrode plates can be provided respectively. As an example, a plurality of positive electrode plates and a plurality of negative electrode plates are alternately arranged in the thickness direction of the electrode plates.

[0139] In some embodiments, the shape of the main body 11 can be cylindrical, flat, or prismatic, etc. First and second pole tabs 12 and 13 can be provided at the end of the main body 11. The first pole tab 12 can be formed by cutting or trimming the current collector substrate of the first electrode plate, or can be connected to the side of the current collector substrate of the first electrode plate by welding. The second pole tab 13 can be formed by cutting or trimming the current collector substrate of the second electrode plate, or can be connected to the side of the current collector substrate of the second electrode plate by welding.

[0140] For an embodiment in which the first electrode plate is a positive electrode plate and the second electrode plate is a negative electrode plate, the first electrode plate includes a positive electrode tab as the first pole tab, and the second electrode plate includes a negative electrode tab as the second pole tab. For an embodiment in which the first electrode plate is a negative electrode plate and the second electrode plate is a positive electrode plate, the first electrode plate includes a negative electrode tab as the first pole tab, and the second electrode plate includes a positive electrode tab as the second pole tab.

[0141] The housing 20 is used to encapsulate the electrode assembly 10, the electrolyte, etc. The housing 20 can be a steel shell, an aluminum shell, a composite metal shell (such as a copper-aluminum composite outer shell), etc.

[0142] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a multi-prismatic battery, and the multi-prismatic battery is, for example, a hexagonal prism battery, etc.

[0143] The housing 20 has a receiving cavity that can accommodate the electrode assembly 10 and the electrolyte, etc., and the housing 20 has an open end 20b that communicates with the receiving cavity for loading the electrode assembly 10, etc. The end cap 30 is provided at the open end 20b for closing the open end 20b so that the open end 20b is hermetically connected to the end cap 30.

[0144] The current collecting assembly 40 is electrically connected to the housing 20, for example, electrically connected to the housing 20 through the end cap 30 or directly electrically connected to the housing 20. The receiving cavity includes a pressure relief cavity pr and an electrical cavity el. The pressure relief cavity pr is located between the current collecting assembly 40 and the end cap 30, and the electrical cavity el is configured to accommodate the electrode assembly 10.

[0145] For the embodiment in which the end cap 30 is electrically connected to the housing 20, the current collecting assembly 40 can be fixedly connected and electrically connected to the end cap 30 by welding or the like, and fixedly connected and electrically connected to the tab of the electrode assembly 10 by welding or the like.

[0146] When assembling the battery cell, the electrode assembly 10 and the current collecting assembly 40 can be first placed into the housing 20, and the electrolyte can be filled into the housing 20, and then the end cap 30 can be closed on the open end of the housing 20 to complete the assembly of the battery cell 20.

[0147] The end cap 30 has a pressure relief portion 50, and at least a part of the pressure relief portion 50 is provided on the wall of the pressure relief cavity pr. The pressure relief portion refers to an element or component that is actuated to release the internal pressure or temperature when the internal pressure or temperature of the battery cell reaches a predetermined threshold. This threshold design varies according to different design requirements. The threshold may depend on one or several materials among the positive electrode plate, negative electrode plate, electrolyte and separator in the battery cell. The pressure relief portion can be in the form of, for example, an explosion-proof valve, a gas valve, a pressure relief valve or a safety valve, and can specifically adopt a pressure-sensitive or temperature-sensitive element or structure, that is, when the internal pressure or temperature of the battery cell reaches a predetermined threshold, the pressure relief portion performs an action or a weak structure provided in the pressure relief portion is damaged, thereby forming an opening or channel for the internal pressure or temperature to be released.

[0148] When thermal runaway or other situations occur in the electrode assembly, the high-temperature and high-pressure gas generated will enter the pressure relief chamber, and the gas may also contain active substances. When the pressure in the pressure relief chamber pr exceeds the designed threshold value, the pressure relief part 50 releases the internal pressure and discharges the emissions from the battery cell. The emissions from the battery cell mentioned here include but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of the separator, high-temperature and high-pressure gas generated by the reaction (such as combustible gases like CH4, CO), flame, and so on.

[0149] At least one channel on the current collector assembly 40 can realize the communication between the electrical chamber el and the pressure relief chamber pr, so that the pressure relief chamber pr can receive the high-temperature and high-pressure gas generated inside the battery cell via at least one channel in the case of thermal runaway or other situations of the electrode assembly.

[0150] For the end cap, the pressure relief part can be integrally formed with the body of the end cap, or can be fixedly connected to the body of the end cap by welding or other means. In Figure 5 A realization structure of the pressure relief part 50 is shown, and a weak area is formed by setting an arc-shaped groove on the surface of the end cap 30, so that when the pressure in the pressure relief chamber pr reaches a value that can break this weak area, the material of this part of the end cap 30 ruptures to form a discharge channel.

[0151] In this embodiment, the current collector assembly 40 is electrically connected to both the electrode assembly 10 and the housing 20 to realize the electrical connection between the electrode assembly 10 and the housing 20, and the pressure relief chamber pr formed between the current collector assembly 40 and the end cap 30 with the pressure relief part 50 can be communicated with the electrical chamber el accommodating the electrode assembly 10 through the channel on the current collector assembly 40. Thus, in the case of thermal runaway or other situations of the electrode assembly 10, the generated gas can quickly enter the pressure relief chamber pr to trigger the pressure relief part 50 provided at least partially on the chamber wall of the pressure relief chamber pr to relieve pressure, thereby reducing the risks such as the expansion, deformation, and rupture of the housing 20 caused by excessive pressure accumulation inside the battery cell 61.

[0152] Refer to Figure 4 , in some embodiments, the housing 20 includes a side wall 21 surrounding the open end 20b and a bottom wall 22 connected to the side wall 21 and opposite to the open end 20b. An electrode terminal 221 is provided on the bottom wall 22. The electrode assembly 10 includes a main body part 11 and a first ear 12 and a second ear 13 with opposite polarities. The first ear 12 is arranged at the end of the main body part 11 adjacent to the end cap 30 and is electrically connected to the current collector assembly 40. The second ear 13 is arranged at the end of the main body part 11 adjacent to the bottom wall 22 and is electrically connected to the electrode terminal 221.

[0153] In this embodiment, the first tab 12 and the second tab 13 of the electrode assembly 10 have opposite polarities and are respectively disposed on one side of the main body 11 adjacent to the end cap 30 and on one side of the main body 11 adjacent to the bottom wall 22 of the housing 20. In this way, the second tab 13 can be directly or electrically connected to the electrode terminal 221 disposed on the bottom wall 22 through the current collector assembly 40'. In this way, the housing 20 and the electrode terminal 221 can be respectively electrically connected to an external conductor to realize the charge and discharge functions.

[0154] In Figure 4 it, the housing 20 is cylindrical, the first tab 12 and the second tab 13 are located at both ends of the main body 11 in the first direction dr1, the end cap 30 and the electrode terminal 221 are respectively located at both ends of the housing 20 in the first direction dr1 and are respectively adjacent to the first tab 12 and the second tab 13. A current collector assembly 40' may also be disposed in the housing 20. The current collector assembly 40' is electrically connected to the electrode terminal 221 and is electrically connected to the second tab 13 of the electrode assembly 10.

[0155] In some other embodiments, the housing 20 is prismatic, and the first tab 12 and the second tab 13 may be located at the same end of the main body 11 in the first direction dr1, or at both ends in the second direction dr2 or the third direction dr3 perpendicular to the first direction dr1.

[0156] In some embodiments, the bottom wall 22 and the side wall 21 are an integrally formed structure.

[0157] In this embodiment, by making the bottom wall 22 and the side wall 21 an integrally formed structure, the overall sealing performance of the housing 20 can be improved, which is beneficial to simplifying the processing and assembly processes.

[0158] Referring to Figure 5 , in some embodiments, the at least one channel includes: a first channel 4A located around the pressure relief chamber pr.

[0159] In this embodiment, the first channel 4A provided along the periphery of the pressure relief chamber pr is used to communicate the electrical chamber el and the pressure relief chamber pr. Substances such as high-pressure gas generated inside the battery cell 61 can enter the pressure relief chamber through the first channel 4A around the pressure relief chamber pr, so as to guide the high-pressure gas in the electrical chamber el around the pressure relief chamber pr to quickly enter the pressure relief chamber pr, improving the pressure relief efficiency.

[0160] In some embodiments, the at least one channel includes a plurality of the first channels 4A, and the plurality of the first channels 4A are arranged at intervals along the periphery of the pressure relief chamber pr.

[0161] Considering that the failure position of the battery cell 61 is random and cannot be determined in advance in the case of thermal runaway or the like, therefore, through a plurality of the first channels 4A arranged at intervals along the periphery of the pressure relief chamber pr, pressure relief paths can be realized in multiple directions on the periphery of the pressure relief chamber pr, thereby improving the pressure relief efficiency of the battery cell 61, helping to reduce the risk of excessive local pressure inside the battery cell 61, and meeting the pressure relief requirements under various failure positions, and improving the consistency of explosion prevention of the battery cell 61.

[0162] Figure 6A FIG. is a schematic structural view of a current collector assembly in some embodiments of the battery cell according to the present disclosure. Figure 6B is Figure 6A a schematic structural view of the first conductive member in the illustrated embodiment. Figure 6C is Figure 6A a schematic structural view of the second conductive member in the illustrated embodiment. Figure 6D is Figure 6A a schematic cross-sectional view of the mounting structure of the end cap, the current collector assembly and the electrode assembly in the illustrated embodiment.

[0163] Referring to Figures 6A - 6D , in some embodiments, the end cap 30 is electrically connected to the housing 20, and the current collector assembly 40 includes: a first conductive member 41 and a second conductive member 42. The first conductive member 41 is welded to the end cap 30 and has a hollow portion 41a penetrating in the thickness direction of the end cap 30. The second conductive member 42 is electrically connected to the first conductive member 41 and is welded to the first tab 12 of the electrode assembly 10 on the side adjacent to the end cap 30. The end cap 30, the hollow portion 41a and the second conductive member 42 enclose the pressure relief chamber pr, and the first channel 4A is disposed between the first conductive member 41 and the second conductive member 42 and communicates with the hollow portion 41a.

[0164] The first channel 4A is disposed between the first conductive member 41 and the second conductive member 42. The first channel 4A may be located on the first conductive member 41 or on the second conductive member 42, or a part may be located on the first conductive member 41 and the other part may be located on the second conductive member 42.

[0165] In this embodiment, a current collector assembly 40 in which the first conductive member 41 and the second conductive member 42 are electrically connected is adopted. The first conductive member 41 is welded to the end cap 30 electrically connected to the housing 20, and the second conductive member 42 is welded to the first tab 12 of the electrode assembly. In this way, the first conductive member 41 and the second conductive member 42 can be adaptively designed according to the materials of the end cap 30 and the first tab 12 respectively, and have better welding compatibility, which helps to reduce the welding quality risk caused by the difference in welding performance of the materials during welding.

[0166] The end cap 30, the hollow portion 41a of the first conductive member 41 and the second conductive member 42 can form a deeper pressure relief chamber pr, which helps to improve the gas flow in the pressure relief chamber pr, and through the cooperation of the first channel provided between the first conductive member and the second conductive member and the hollow portion 41a on the first conductive member 41, the pressure relief chamber pr can receive the high-pressure gas in the battery cell 61 more quickly, thereby improving the pressure relief efficiency.

[0167] In some embodiments, the base material of the end cap 30 is different from that of the first pole tab 12, and the first conductive member 41 is the same as that of the end cap 30. In some embodiments, the base material of the end cap 30 is different from that of the first pole tab 12, and the second conductive member 42 is the same as that of the first pole tab 12. In some embodiments, the base material of the end cap 30 is different from that of the first pole tab 12, the first conductive member 41 is the same as that of the end cap 30, and the second conductive member 42 is the same as that of the first pole tab 12.

[0168] In this embodiment, in the case where the end cap 30 and the first pole tab 12 are different in material, the base material of the first conductive member 41 can be set to be the same as the base material of the end cap 30, so that it is easier to obtain good welding quality between the end cap 30 and the first conductive member 41, which helps to reduce the conductivity between the end cap 30 and the first conductive member 41 and reduce the risk of end cap leakage due to poor welding quality. Setting the base material of the second conductive member 42 to be the same as the base material of the first pole tab 12 helps to reduce the conductivity between the second conductive member 42 and the first pole tab 12, thereby reducing the internal resistance of the battery cell 61.

[0169] Here, the same matrix material means that the material contains the same main element, and the mass percentage of the main element is greater than the mass percentage of other elements in the material. For example, the main element of aluminum and various grades of aluminum alloys is aluminum. If the matrix materials of the end cap and the first conductive part are both aluminum alloys and the main element is aluminum, it means that the end cap and the first conductive part have the same matrix material. For another example, if the material of the second conductive part is copper alloy and the material of the first pole ear is copper, and the main element is copper, it means that the matrix material of the second conductive part and the first pole ear is the same.

[0170] Different base materials refer to materials containing different main elements, and the mass percentage of the main element is greater than the mass percentages of other elements in the material. For example, if the material of the end cap is steel and its main element is iron, while the material of the first tab is elemental copper and its main element is copper, it means that the base materials of the end cap and the first tab are different. In some other embodiments, the base materials of the end cap 30 and the first tab 12 are the same, and the first conductive member 41 and the second conductive member 42 can be set to have the same base material as the first tab 12.

[0171] In some embodiments, the base materials of both the end cap 30 and the first conductive member 41 are steel, and the base materials of both the first tab 12 and the second conductive member 42 are copper.

[0172] In this embodiment, the base materials of the end cap 30 and the first tab 12 are different. The base material of the end cap is steel, while the base material of the first tab 12 is copper. By setting the base materials of both the end cap 30 and the first conductive member 41 to be steel, it not only helps improve the welding quality between them, but also can improve the mechanical properties of the end cap 30 and reduce the material cost. And by setting the base materials of both the first tab 12 and the second conductive member 42 to be copper, a relatively high electrical conductivity can be achieved.

[0173] Reference Figure 6D , in some embodiments, a first portion 31 of the end cap 30 that defines the pressure relief chamber pr protrudes in a direction away from the electrode assembly 10 relative to a second portion 32 of the end cap 30 that is welded to the first conductive member 41.

[0174] In this embodiment, a first portion 31 of the end cap 30 that defines the pressure relief chamber pr protrudes in a direction away from the electrode assembly 10 relative to a second portion 32 of the end cap 30 that is welded to the first conductive member 41. A side wall of the first portion 31 adjacent to the electrode assembly 10 can cooperate with the hollow portion 41a of the first conductive member 41 and the second conductive member 42 to define a relatively deep pressure relief chamber pr, which is beneficial to the gas flow inside the pressure relief chamber pr. And the second portion 32 is fixedly connected to the first conductive member 41, enabling the end cap 30 to be reliably fixed to the current collector assembly 40 inside the housing 20.

[0175] Reference Figure 6C and Figure 6D , in some embodiments, the second conductive member 42 has a first welding portion 421 and a second welding portion 422. The first welding portion 421 is welded to the first tab 12, and the second welding portion 422 at least partially surrounds the first welding portion 421 and is welded to the first conductive member 41.

[0176] In this embodiment, the second welding portion 422 at least partially surrounds the first welding portion 421, so that the first welding portion 421 welded to the first tab and the second welding portion 422 welded to the first conductive member 41 can be staggered, which can reduce the interference between the two sets of welding relationships, thereby facilitating the reduction of the welding difficulty. The first channel may be located between the first welding portion 421 and the second welding portion 422 to guide the high-pressure gas generated between the first tab 12 and the housing 20 into the pressure relief chamber pr.

[0177] In Figure 6C order to conveniently show the first welding portion 421 and the second welding portion 422 of the second conductive member 42, the first welding portion 421 and the second welding portion 422 are demarcated by a dashed line circle with shading. The dashed line circle is consistent with the outer circle of the hollow portion 41a of the first conductive member 41 in Figure 6B shape and size. The portion of the second conductive member 42 located radially inside the dashed line circle is the first welding portion 421, and the portion located radially outside the dashed line circle is the second welding portion 422.

[0178] Referring to Figures 6A - 6C , in some embodiments, the electrode assembly 10 is a cylindrical electrode assembly 10, the second conductive member 42 includes a plate body 42a, the edge region of the plate body 42a (which can be used as the second welding portion 422) is welded to the first conductive member 41, and a notch 42b is formed, and the notch 42b serves as the first channel 4A and is at least partially exposed in the hollow portion 41a.

[0179] In this embodiment, a notch 42b serving as the first channel 4A is formed in the edge region of the plate body 42a, so that the high-pressure gas generated in the electrical cavity el in the case of thermal failure or the like can enter the pressure relief chamber pr from the position exposed in the hollow portion 41a through the notch 42b from the periphery of the plate body 42a. The edge region of the plate body 42a is welded to the first conductive member 41, which can not only strengthen the current collecting assembly 40 in terms of strength and stiffness, but also has a relatively simple structure, which is beneficial to manufacturing and assembly.

[0180] Referring to Figure 6C , in some embodiments, the at least one channel further includes: a second channel 4B formed in the center of the plate body 42a, and the portion of the plate body 42a between the second channel 4B and the edge region is welded to the first tab 12.

[0181] In this embodiment, a second channel 4B is formed at the center of the plate body 42a, and the electrical cavity el and the pressure relief cavity are communicated at the center of the end adjacent to the electrode assembly 10, so as to more conveniently receive the high-pressure gas generated by the electrode assembly 10. Moreover, the portion of the plate body 42a between the second channel 4B and the edge region (which can be used as the first welding portion 421) is welded to the first tab 12, which can achieve a larger-area welding with the first tab 12, helping to reduce the welding difficulty and improve the welding quality.

[0182] In Figure 6A , the first conductive member 41 is in surface contact with the second conductive member 42 and can be fixedly connected by welding. The first conductive member 41 and the second conductive member 42 can adopt different base materials. Both the first conductive member 41 and the second conductive member 42 are located inside the housing 20. Even though the welding performance between them is not as good as that between the same materials, since their welding position is inside the housing 20, the airtightness of the end cap welding position will not be affected.

[0183] In Figure 6B , the first conductive member 41 is an annular plate body having a hollow portion 41a, and the hollow portion 41a is the space surrounded by the circular inner ring. In Figure 6A and Figure 6C , the plate body 42a in the second conductive member 42 is generally circular as a whole, and can form a good planar contact with the annular plate body, so as to form a larger-area fixed connection and electrical connection after welding, which is beneficial to improving the mechanical properties and electrical conductivity. The plate body 42a in the second conductive member 42 is provided with a second channel 4B at the center and a notch 42b at the edge region. It can be seen that the portions of the second channel 4B and the notch 42b can be exposed to the hollow portion 41a of the first conductive member 41. The second channel 4B can also be used for positioning during the process of introducing the electrolyte.

[0184] In Figure 6D , the process of entering the pressure relief cavity pr surrounded by the plate body 42a, the first conductive member 41 and the end cap 30 respectively from the central hole 14 of the electrode assembly 10 through the second channel 4B and from the side through the notch 42b is schematically shown by a plurality of short hollow black arrows. In the cross-section of the end cap 30, the portion without pattern filling is set to schematically show the area corresponding to the pressure relief portion 50.

[0185] In order to expose a part of the notch 42b to the hollow portion 41a of the first conductive member 41, the minimum distance from the notch 42 to the center of the plate body 42a can be made less than the radius of the hollow portion 41a.

[0186] Refer to Figure 6A and Figure 6C , in some embodiments, a plurality of notches 42b are formed in the edge region of the plate body 42a, and the plurality of notches 42b are arranged at intervals along the circumferential direction of the plate body 42a.

[0187] In this embodiment, a plurality of first channels 4A are formed by a plurality of notches 42b arranged at circumferential intervals of the plate body 42a, so that pressure relief paths can be realized in multiple directions around the pressure relief cavity pr, thereby improving the pressure relief efficiency of the battery cell 61 and reducing the risk of excessive local pressure.

[0188] In Figure 6C , four notches 42b are formed in the edge region of the plate body 42a, and each notch 42b has three straight edges perpendicular to each other in sequence. In other embodiments, the number of notches 42b can be less or more, the shapes of the respective notches 42b can be the same or different, the sizes of the respective notches 42b can be the same or different, and the notch 42b can have at least one straight edge, at least one arc edge, or a combined edge including a straight edge segment and an arc edge segment.

[0189] Reference Figure 6C , in some embodiments, the plurality of notches 42b are arranged at equal circumferential intervals along the plate body 42a.

[0190] In this embodiment, arranging the plurality of notches 42b at equal circumferential intervals along the plate body 42a enables high-pressure gas to enter the pressure relief cavity pr more uniformly to achieve pressure relief.

[0191] In Figure 6C , the four notches 42b are evenly distributed in the edge region of the plate body 42a at intervals of 90°. The sizes of the respective notches 42b are the same, and the shapes are also the same.

[0192] In other embodiments, the plurality of notches 42b can be symmetric with respect to the center of the plate body 42a or a straight line passing through the center in the edge region of the plate body 42a. This is also beneficial for enabling high-pressure gas to enter the pressure relief cavity pr more uniformly to achieve pressure relief.

[0193] Figure 7A FIG. [FIG. number] is a schematic structural diagram of a current collector assembly in other embodiments of the battery cell according to the present disclosure. Figure 7B FIG. [FIG. number] is Figure 7A a schematic structural diagram of the first conductive member in the embodiment shown in FIG. [FIG. number]. Figure 7C FIG. [FIG. number] is Figure 7A a schematic structural diagram of the second conductive member in the embodiment shown in FIG. [FIG. number]. Figure 7D FIG. [FIG. number] is Figure 7A a schematic cross-sectional view of the installation structure of the end cap, current collector assembly, and electrode assembly in the embodiment shown in FIG. [FIG. number]. Figure 7E FIG. [FIG. number] is Figure 7D an enlarged schematic view of the circled area of the dashed ellipse A in FIG. [FIG. number]. Figure 7F FIG. [FIG. number] is Figure 7E a schematic diagram of the dimensions of the current collector assembly in FIG. [FIG. number].

[0194] Reference Figures 7A - 7E, in some embodiments, the electrode assembly 10 is a cylindrical electrode assembly 10. The second conductive member 42 includes a flat portion 42d and a convex portion 42e. The convex portion 42e protrudes from the flat portion 42d in a direction away from the electrode assembly 10, forming a recessed portion 42g on the inner side. The orthographic projection of the recessed portion 42g on the first conductive member 41 at least partially coincides with the hollow portion 41a, and the convex portion 42e is welded to the first conductive member 41; the first channel 4A is provided in the convex portion 42e.

[0195] For embodiments of the battery cell including a cylindrical electrode assembly, the convex portion 42e can form a support structure with high strength and stiffness, improving the mechanical properties of the current collector assembly 40. Moreover, the recessed portion 42g formed inside the convex portion 42e of the second conductive member 42 can cooperate with the hollow portion 41a of the first conductive member 41 to form a deeper pressure relief cavity pr, which helps to improve the gas flow inside the pressure relief cavity pr. Additionally, the convex portion 42e (which can serve as the second welding portion 422) is welded to the first conductive member 41, and the welding position between the convex portion 42e and the first conductive member 41 is far from the flat portion 42e, which can reduce the influence of the welding here on the welding of the flat portion 42e.

[0196] In some embodiments, the convex portion 42e is formed with a first groove 42h on the side adjacent to the electrode assembly 10, which is recessed from the flat portion 42d in a direction away from the electrode assembly 10. The inner side wall of the convex portion 42e is located between the first annular groove 42h and the recessed portion 42g, and a third through hole 42i is provided. The first annular groove 42h and the third through hole 42i serve as at least a part of the first channel 4A.

[0197] In this embodiment, the second conductive member 42 is formed with a first groove 42h on the side adjacent to the electrode assembly 10 by using the convex portion 42e. In this way, a gap can be formed between the first groove 42h and the first tab 12, reducing the risk that the first channel 4A on the second conductive member 42 is blocked by the first tab 12 due to the first tab 12 being in contact.

[0198] The third through hole is provided on the inner side wall of the convex portion located between the recessed portion 42g and the first groove 42h, and can guide the high-pressure air flow entering the first groove 42h to the inner side of the recessed portion 42g.

[0199] Reference Figure 7C , in some embodiments, the at least one channel further includes: a second channel 4B opened at the center of the flat portion 42d, and the portion of the flat portion 42d outside the second channel 4B is welded to the first tab 12.

[0200] In this embodiment, a second channel 4B is provided at the center of the flat part 42d, and the electrical cavity el and the pressure relief cavity pr are communicated at the center of the end part adjacent to the electrode assembly 10, so as to more conveniently receive the high-pressure gas generated by the electrode assembly 10. Moreover, the part of the flat part 42d outside the second channel 4B (which can be used as the first welding part 421) is welded to the first tab 12, which can achieve a larger-area welding with the first tab 12, helping to reduce the welding difficulty and improve the welding quality.

[0201] In some embodiments, the convex part 42e is annular and forms the annular first groove 42h.

[0202] In this embodiment, by making the convex part 42e annular, a recessed part 42g with continuous side edges can be surrounded to cooperate with the hollow part 41a of the first conductive part 41 to form the pressure relief cavity pr. Moreover, the annular convex part 42e forming the annular first groove 42h can achieve circumferential rectification and diversion of the high-pressure air flow at different circumferential positions, thereby improving the consistency of the pressure relief speed caused by the gas pressure difference inside the battery cell, and further improving the pressure relief efficiency.

[0203] This structure in which the annular convex part 42e surrounds the circular flat part 42d can be obtained by stamping the circular plate, which is beneficial to improving the production efficiency. In some other embodiments, the annular convex part 42e and the circular flat part 42d can be independently manufactured and fixedly connected to each other by welding or other means.

[0204] In Figure 7A the annular convex part 42e serves as the second welding part 422 and is in surface contact with the first conductive part 41 and fixedly connected by welding. The first conductive part 41 and the second conductive part 42 can adopt different base materials, and the fixedly connected first conductive part 41 and second conductive part 42 are both located inside the housing 20, which will not affect the sealing performance of the end cover.

[0205] In Figure 7B the first conductive part 41 has a hollow part 41a and is integrally annular, and the hollow part 41a is the space surrounded by the inner ring of the annular shape. In Figure 7A and Figure 7C the annular convex part 42e protrudes upward relative to the flat part 42d, and the convex part 42e has an annular plane to form a good planar contact with the first conductive part 41, so as to form a larger-area fixed connection and electrical connection after welding, which is beneficial to improving the mechanical properties and electrical conductivity.

[0206] In Figure 7DAmong them, the convex portion 42e and the flat portion 42d enclose a recessed portion 42g located above the flat portion 42d, and the orthographic projection of the recessed portion 42g on the first conductive member 41 at least partially coincides with the hollow portion 41a. A first groove 42h is formed on the lower side of the annular convex portion 42e, and a third through hole 42i is provided between the first groove 42h and the recessed portion 42g.

[0207] Figure 7D Among them, the process of entering the pressure relief cavity pr surrounded by the recessed portion 42g, the hollow portion 41a, and the end cap 30 from the central hole 14 of the electrode assembly 10 through the second channel 4B, and entering the pressure relief cavity pr from the side through the first groove 42h and the third through hole 42i is schematically shown by a plurality of short hollow black arrows. In the cross-section of the end cap 30, a portion without pattern filling is provided to indicate the area corresponding to the pressure relief portion 50.

[0208] Reference Figure 7A and Figure 7C In some embodiments, the convex portion 42e is provided with a plurality of the third through holes 42i between the first groove 42h and the recessed portion 42g, and the plurality of the third through holes 42i are arranged at intervals along the circumferential direction of the second conductive member 42.

[0209] In this embodiment, a plurality of first channels 4A are formed by cooperating with the first groove through a plurality of third through holes 42i arranged at intervals along the circumferential direction of the second conductive member 42 between the first groove 42h and the recessed portion 42g, so that pressure relief paths can be realized in multiple directions around the pressure relief cavity pr, thereby improving the pressure relief efficiency of the battery cell 61 and reducing the risk of excessive local pressure.

[0210] In some embodiments, the plurality of third through holes 42i are arranged at equal intervals along the circumferential direction of the second conductive member 42.

[0211] In this embodiment, by arranging the plurality of third through holes 42i at equal intervals along the circumferential direction of the second conductive member 42, high-pressure gas can enter the pressure relief cavity pr more evenly to achieve pressure relief.

[0212] Reference Figure 7A and Figure 7E In some embodiments, a protruding edge 42j further extends outward from the outside of the convex portion 42e.

[0213] In this embodiment, a protruding edge 42j extends from the outside of the convex portion 42e. The protruding edge 42j can increase the extrusion surface area between the bent edge of the convex portion 42e and the first tab 12, and reduce the risk of the tab being damaged due to excessive pressure.

[0214] Reference Figure 7D and Figure 7E, in some embodiments, the end face of the protruding edge 42j adjacent to one side of the electrode assembly 10 is flush with the end face of the flat plate portion 42d adjacent to one side of the electrode assembly 10.

[0215] In this embodiment, by making the end face of the protruding edge 42j adjacent to one side of the electrode assembly 10 flush with the end face of the flat plate portion 42d, the extrusion surface area between the bent edge of the convex portion 42e and the first tab 12 can be further increased.

[0216] Figure 7F Shows the Figure 7E structural dimensional relationship after hiding the end cap and the electrode assembly on the basis of. Refer to Figure 7E and Figure 7F , in some embodiments, the first conductive member 41 is in a circular ring shape, the outer ring radius D1 of the first conductive member 41 is greater than the maximum distance D2 from the outer side wall of the convex portion 42e to the center of the recessed portion 42g, the first conductive member 41, the protruding edge 42j and the convex portion 42e jointly enclose a second groove 42k located outside the convex portion 42e, the outer side wall of the convex portion 42e is disposed between the second groove 42k and the first groove 42h, and a fourth through hole 42l is opened, and the second groove 42k, the first groove 42h, the fourth through hole 42l and the third through hole 42i serve as at least a part of the first channel 4A.

[0217] In this embodiment, the outer ring radius of the first conductive member 41 is greater than the maximum distance D2 from the outer side wall of the convex portion 42e to the center of the recessed portion 42g (for the annular convex portion 42e, this maximum distance D2 is the outer ring radius of the convex portion 42e), so that a second groove 42k can be formed after the first conductive member 41 is welded to the convex portion 42e, and the fourth through hole 42l opened on the outer side wall of the convex portion 42e between the second groove 42k and the first groove 42h can guide the high-pressure gas outside the current collecting assembly 40, so that the high-pressure gas enters the inner side of the recessed portion 42g through the fourth through hole 42l, the first groove 42h and the third through hole 42i.

[0218] Refer to Figure 7E , in some embodiments, a plurality of the fourth through holes 42l are opened on the outer side wall of the convex portion 42e between the second groove 42k and the first groove 42h, and a plurality of the third through holes 42i are opened between the first annular groove 42h and the recessed portion 42g, the plurality of the third through holes 42i and the plurality of the fourth through holes 42l are both arranged at intervals along the circumferential direction of the second conductive member 42, and at least part of the plurality of the third through holes 42i and the plurality of the fourth through holes 42l are aligned or staggered in the radial direction.

[0219] In this embodiment, a plurality of fourth through holes 42l and a plurality of third through holes 42i are arranged at equal intervals along the circumferential direction of the second conductive member 42, and at least part of the plurality of third through holes 42i and the plurality of fourth through holes 42l are aligned or offset in the radial direction, so that the high-pressure gas in different directions of the flow guiding assembly can enter the pressure relief cavity pr more uniformly to achieve pressure relief.

[0220] In Figure 7E it also schematically shows the process of entering the pressure relief cavity pr from the side through the second groove 42k, the fourth through hole 42l, the first groove 42h and the third through hole 42i by a plurality of short black hollow arrows. And, Figure 7E it also schematically shows the case where the third through hole 42i and the fourth through hole 42l are aligned and located in the same cross section.

[0221] In some embodiments, the convex portion 42e is annular and together with the first conductive member 41 and the protruding edge 42j encloses an annular second groove 42k.

[0222] In this embodiment, by making the convex portion 42e annular, a recessed portion 42g with continuous side edges can be enclosed so as to cooperate with the hollow portion 41a of the first conductive member 41 to form the pressure relief cavity pr. Moreover, the annular convex portion 42e and the first conductive member 41 and the protruding edge 42j together enclose an annular second groove 42k, which can achieve circumferential rectification and flow guiding effects on the high-pressure air flows at different circumferential positions on the outside, thereby improving the consistency of the pressure relief speed caused by the gas pressure difference inside the battery cell and further improving the pressure relief efficiency.

[0223] Each of the above embodiments of the battery cell 61 can be used in various batteries. Therefore, in one aspect of the present disclosure, there is provided a battery 60 including the battery cell 61 of any one of the foregoing embodiments.

[0224] The battery using the battery cell of the foregoing embodiment has good reliability.

[0225] Each of the above embodiments of the battery 60 can be used in various electrical devices. Therefore, in one aspect of the present disclosure, there is provided an electrical device including the battery 60 of any one of the foregoing embodiments.

[0226] The electrical device using the battery of the foregoing embodiment has good reliability.

[0227] In some specific embodiments, such as Figures 3 - 6DAs shown, the battery cell 61 includes: an electrode assembly 10, a housing 20, an end cap 30, and a current collecting assembly 40. The housing 20 has a receiving cavity for receiving the electrode assembly 10 and an open end 20b communicating with the receiving cavity. The end cap 30 covers the open end 20b. The current collecting assembly 40 is electrically connected to the electrode assembly 10, and the current collecting assembly 40 is electrically connected to the housing 20 through the end cap 30. The receiving cavity includes a pressure relief cavity pr and an electrical cavity el. The pressure relief cavity pr is located between the current collecting assembly 40 and the end cap 30, and the electrical cavity el is configured to receive the electrode assembly 10. The end cap 30 has a pressure relief portion 50, and at least a part of the pressure relief portion 50 is provided on the wall of the pressure relief cavity pr. The current collecting assembly 40 has a plurality of channels communicating the electrical cavity el and the pressure relief cavity pr.

[0228] The current collecting assembly 40 includes a first conductive member 41 and a second conductive member 42. The first conductive member 41 is welded to the end cap 30 and has a hollow portion 41a penetrating in the thickness direction of the end cap 30. The second conductive member 42 is electrically connected to the first conductive member 41 and is welded to a first tab 12 of the electrode assembly 10 on a side adjacent to the end cap 30. A plurality of first channels 4A are located between the first conductive member 41 and the second conductive member 42 and are all communicated with the hollow portion 41a. The base materials of the end cap 30 and the first conductive member 41 are both steel, and the base materials of the first tab 12 and the second conductive member 42 are both copper.

[0229] The electrode assembly 10 is a cylindrical electrode assembly 10. The second conductive member 42 includes a plate body 42a. The edge region of the plate body 42a is welded to the first conductive member 41 and is provided with a notch 42b. The notch 42b is exposed to the hollow portion 41a as the first channel 4A. A second channel 4B is provided at the center of the plate body 42a. The portion of the plate body 42a between the second channel 4B and the edge region is welded to the first tab 12. A plurality of notches 42b are provided in the edge region of the plate body 42a, and the plurality of notches 42b are arranged at equal intervals along the circumference of the plate body 42a.

[0230] In some other specific embodiments, such as Figures 3 - 4 、 Figures 7A - 7EAs shown, the battery cell 61 includes: an electrode assembly 10, a housing 20, an end cap 30, and a current collector assembly 40. The housing 20 has a receiving cavity for receiving the electrode assembly 10 and an open end 20b communicating with the receiving cavity. The end cap 30 covers the open end 20b. The current collector assembly 40 is electrically connected to the electrode assembly 10, and the current collector assembly 40 is electrically connected to the housing 20 through the end cap 30. The receiving cavity includes a pressure relief cavity pr and an electrical cavity el. The pressure relief cavity pr is located between the current collector assembly 40 and the end cap 30. The electrical cavity el is configured to receive the electrode assembly 10. The end cap 30 has a pressure relief portion 50, and at least a part of the pressure relief portion 50 is provided on the cavity wall of the pressure relief cavity pr. The current collector assembly 40 has a plurality of channels communicating the electrical cavity el and the pressure relief cavity pr.

[0231] The current collector assembly 40 includes: a first conductive member 41 and a second conductive member 42. The first conductive member 41 is welded to the end cap 30 and has a hollow portion 41a penetrating in the thickness direction of the end cap 30. The second conductive member 42 is electrically connected to the first conductive member 41 and is welded to a first tab 12 of the electrode assembly 10 on a side adjacent to the end cap 30. A plurality of first channels 4A are located in the second conductive member 42 and are all communicated with the hollow portion 41a. The base materials of the end cap 30 and the first conductive member 41 are both steel, and the base materials of the first tab 12 and the second conductive member 42 are both copper.

[0232] The electrode assembly 10 is a cylindrical electrode assembly 10. The second conductive member 42 includes a flat plate portion 42d and a convex portion 42e. The convex portion 42e protrudes from the flat plate portion 42d in a direction away from the electrode assembly 10, and a recessed portion 42g is formed inside. The orthographic projection of the recessed portion 42g on the first conductive member 41 at least partially coincides with the hollow portion 41a, and the convex portion 42e is welded to the first conductive member 41.

[0233] On a side of the convex portion 42e adjacent to the electrode assembly 10, a first groove 42h is formed that is recessed from the flat plate portion 42d in a direction away from the electrode assembly 10. The inner side wall of the convex portion 42e is located between the first groove 42h and the recessed portion 42g and is provided with a third through hole 42i. The first groove 42h and the third through hole 42i serve as at least a part of the first channels 4A.

[0234] A plurality of third through holes 42i are formed in the convex portion 42e between the first groove 42h and the recessed portion 42g, and the plurality of third through holes 42i are arranged at equal intervals in the circumferential direction of the second conductive member 42.

[0235] An outward extending flange 42j also projects from the outer side of the convex portion 42e. The end face of the flange 42j adjacent to the electrode assembly 10 is flush with the end face of the flat portion 42d adjacent to the electrode assembly 10.

[0236] The first conductive member 41 is annular. The outer ring radius D1 of the first conductive member 41 is greater than the maximum distance D2 from the outer sidewall of the convex portion 42e to the center of the recessed portion 42g. The first conductive member 41, the flange 42j and the convex portion 42e jointly enclose a second groove 42k located outside the convex portion 42e. The outer sidewall of the convex portion 42e is disposed between the second groove 42k and the first groove 42h and is provided with a fourth through hole 42l. The second groove 42k, the first groove 42h, the fourth through hole 42l and the third through hole 42i serve as at least a part of the first channel 4A.

[0237] A plurality of fourth through holes 42l are provided in the outer sidewall of the convex portion 42e between the second groove 42k and the first groove 42h, and a plurality of third through holes 42i are provided between the first groove 42h and the recessed portion 42g. The plurality of third through holes 42i and the plurality of fourth through holes 42l are both arranged at intervals along the circumferential direction of the second conductive member 42, and at least part of the plurality of third through holes 42i and the plurality of fourth through holes 42l are radially aligned.

[0238] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not intended to limit them; although the present disclosure has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that it is still possible to modify the specific implementation manners of the present disclosure or perform equivalent replacements for some technical features; without departing from the spirit of the technical solutions of the present disclosure, they should all be covered within the scope of the technical solutions claimed by the present disclosure.

Claims

1. A battery cell (61), characterized in that: include: An electrode assembly (10); A housing (20) having a receiving cavity and an open end (20b) communicating with the receiving cavity; An end cover (30) covering the open end (20b); a current collecting assembly (40) electrically connected to the electrode assembly (10) and the shell (20), the accommodating chamber comprising a pressure relief chamber (pr) and an electrical chamber (el), the pressure relief chamber (pr) being located between the current collecting assembly (40) and the end cover (30), and the electrical chamber (el) being configured to accommodate the electrode assembly (10); The end cover (30) has a pressure relief portion (50), at least a portion of which is disposed on the cavity wall of the pressure relief cavity (pr), and the current collecting assembly (40) has at least one channel connecting the electrical cavity (el) and the pressure relief cavity (pr).

2. The battery cell (61) according to claim 1, characterized in that: The at least one channel includes: a first channel (4A) located around the pressure relief chamber (pr).

3. The battery cell (61) according to claim 1, characterized in that: The at least one channel includes a plurality of first channels (4A), and the plurality of first channels (4A) are arranged at intervals along the periphery of the pressure relief chamber (pr).

4. The battery cell (61) according to claim 3, characterized in that: The plurality of first channels (4A) are arranged at equal intervals along the periphery of the pressure relief chamber (pr).

5. The battery cell (61) according to any one of claims 2 to 4, characterized in that: The end cover (30) is electrically connected to the housing (20), and the current collecting assembly (40) comprises: A first conductive member (41) is welded to the end cover (30) and has a hollow portion (41a) penetrating in the thickness direction of the end cover (30); and A second conductive member (42) is electrically connected to the first conductive member (41) and is welded to a first electrode tab (12) of the electrode assembly (10) on a side adjacent to the end cover (30); The end cover (30), the hollow portion (41a) and the second conductive member (42) enclose the pressure relief chamber (pr); the first channel (4A) is arranged between the first conductive member (41) and the second conductive member (42) and is connected to the hollow portion (41a).

6. The battery cell (61) according to claim 5, characterized in that: The end cap (30) and the first electrode tab (12) are made of different base materials; The first conductive member (41) and the end cover (30) are made of the same base material, and / or the second conductive member (42) and the first pole tab (12) are made of the same base material.

7. The battery cell (61) according to claim 6, characterized in that: The base materials of the end cover (30) and the first conductive member (41) are both steel, and the base materials of the first pole tab (12) and the second conductive member (42) are both copper.

8. The battery cell (61) according to claim 5, characterized in that: The electrode assembly (10) is a cylindrical electrode assembly, the second conductive member (42) comprises a plate body (42a), the edge region of the plate body (42a) is welded to the first conductive member (41), and a notch (42b) is provided, the notch (42b) serving as the first channel (4A) being at least partially exposed in the hollow portion (41a).

9. The battery cell (61) according to claim 8, characterized in that: A plurality of notches (42b) are provided in the edge region of the plate body (42a), and the plurality of notches (42b) are arranged at intervals along the circumference of the plate body (42a).

10. The battery cell (61) according to claim 9, characterized in that: The plurality of notches (42b) are arranged at equal intervals along the circumference of the plate body (42a).

11. The battery cell (61) according to claim 8, characterized in that: The at least one channel further comprises: a second channel (4B) opened at the center of the plate body (42a), and a portion of the plate body (42a) located between the second channel (4B) and the edge region is welded to the first pole lug (12).

12. The battery cell (61) according to claim 5, characterized in that: The electrode assembly (10) is a cylindrical electrode assembly; the second conductive member (42) comprises a flat portion (42d) and a convex portion (42e); the convex portion (42e) protrudes from the flat portion (42d) in a direction away from the electrode assembly (10) and forms a concave portion (42g) on ​​the inner side; the positive projection of the concave portion (42g) on ​​the first conductive member (41) at least partially overlaps with the hollow portion (41a); the convex portion (42e) is welded to the first conductive member (41); and the first channel (4A) is arranged on the convex portion (42e).

13. The battery cell (61) according to claim 12, characterized in that: The convex portion (42e) is formed with a first groove (42h) on a side adjacent to the electrode assembly (10), which is recessed from the flat portion (42d) in a direction away from the electrode assembly (10); the inner side wall of the convex portion (42e) is located between the first groove (42h) and the recessed portion (42g), and is provided with a third through hole (42i); the first groove (42h) and the third through hole (42i) serve as at least a part of the first channel (4A).

14. The battery cell (61) according to claim 13, characterized in that: The convex portion (42e) is provided with a plurality of third through holes (42i) between the first groove (42h) and the recessed portion (42g), and the plurality of third through holes (42i) are arranged at intervals along the circumferential direction of the second conductive member (42).

15. The battery cell (61) according to claim 14, characterized in that: The plurality of third through holes (42i) are arranged at equal intervals along the circumference of the second conductive member (42).

16. The battery cell (61) according to claim 13, characterized in that: The outer side of the protrusion (42e) also extends outwardly to form a protruding edge (42j).

17. The battery cell (61) according to claim 16, characterized in that: The end surface of the protruding edge (42j) adjacent to the electrode assembly (10) is flush with the end surface of the flat plate portion (42d) adjacent to the electrode assembly (10).

18. The battery cell (61) according to claim 16, characterized in that: The first conductive member (41) is in the shape of a ring. The outer ring radius (D1) of the first conductive member (41) is greater than the maximum distance (D2) from the outer side wall of the convex portion (42e) to the center of the concave portion (42g). The first conductive member (41), the protruding edge (42j) and the convex portion (42e) together enclose a second groove (42k) located outside the convex portion (42e). The outer side wall of the convex portion (42e) is arranged between the second groove (42k) and the first groove (42h), and is provided with a fourth through hole (42l). The second groove (42k), the first groove (42h), the fourth through hole (42l) and the third through hole (42i) serve as at least a part of the first channel (4A).

19. The battery cell (61) according to claim 18, characterized in that: The outer wall of the convex portion (42e) is provided with a plurality of fourth through holes (42l) between the second groove (42k) and the first groove (42h), and a plurality of third through holes (42i) are provided between the first groove (42h) and the recessed portion (42g), the plurality of third through holes (42i) and the plurality of fourth through holes (42l) are arranged at intervals along the circumference of the second conductive member (42), and the plurality of third through holes (42i) and the plurality of fourth through holes (42l) are at least partially aligned or staggered in the radial direction.

20. The battery cell (61) according to claim 13, characterized in that: The convex portion (42e) is annular and forms the first annular groove (42h).

21. The battery cell (61) according to claim 18, characterized in that: The convex portion (42e) is annular and, together with the first conductive member (41) and the protruding edge (42j), forms an annular second groove (42k).

22. The battery cell (61) according to claim 12, characterized in that: The at least one channel further comprises: a second channel (4B) opened at the center of the flat plate portion (42d), and a portion of the flat plate portion (42d) outside the second channel (4B) is welded to the first electrode tab (12).

23. The battery cell (61) according to claim 5, characterized in that: A first portion (31) on the end cover (30) for enclosing the pressure relief chamber (pr) protrudes in a direction away from the electrode assembly (10) relative to a second portion (32) on the end cover (30) for welding to the first conductive member (41).

24. The battery cell (61) according to claim 1, characterized in that: The shell (20) comprises a side wall (21) surrounding the open end (20b) and a bottom wall (22) connected to the side wall (21) and opposite to the open end (20b), and an electrode terminal (221) is provided on the bottom wall (22). The electrode assembly (10) comprises a main body (11) and a first pole lug (12) and a second pole lug (13) with opposite polarities, wherein the first pole lug (12) is arranged at an end of the main body (11) adjacent to the end cover (30) and is electrically connected to the current collecting assembly (40), and the second pole lug (13) is arranged at an end of the main body (11) adjacent to the bottom wall (22) and is electrically connected to the electrode terminal (221).

25. The battery cell (61) according to claim 24, characterized in that: The bottom wall (22) and the side wall (21) are an integrally formed structure.

26. A battery (60), characterized in that: include: A battery cell (61) according to any one of claims 1 to 25.

27. An electrical device, characterized in that: include: A battery (60) as claimed in claim 26.

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