A battery and an electric device

Abstract

The application discloses a battery and an electric device. The battery comprises a shell, a containing cavity is arranged in the shell, the shell is provided with a first wall, a first through hole is arranged on the first wall, the first through hole is communicated with the containing cavity, a battery cell is arranged in the containing cavity, an electrode terminal is at least partially arranged in the first through hole and is fixed to the first wall, a first current collector is arranged in the containing cavity and is arranged between one end surface of the battery cell and the electrode terminal, the electrode terminal is electrically connected to the battery cell through the first current collector, a first insulating part is at least partially arranged on one side of the first wall facing the containing cavity, the first insulating part is arranged on one side of the first current collector away from the battery cell, the first insulating part is connected to the first current collector to form a separation cavity, and the separation cavity is configured to separate the containing cavity from the first wall when the first current collector presses the first insulating part. In the battery thermal runaway process, the first wall of the shell is prevented from being deformed, and the electrode terminal is prevented from flying out of the shell.

Description

Technical Field

[0001] This invention belongs to the field of battery technology, specifically relating to a battery and an electrical device. Background Technology

[0002] With the rapid growth in demand for renewable, pollution-free, small, discrete, and portable high-performance power sources, countries around the world are vigorously developing green and efficient secondary batteries. Cylindrical batteries, as a new type of secondary battery, have advantages such as high energy density and power density, high operating voltage, light weight, small size, long cycle life, good safety, and environmental friendliness. They have broad application prospects in portable electrical appliances, power tools, large-scale energy storage, and electric transportation power supplies.

[0003] A cylindrical battery comprises a casing, a cell, terminals, and an explosion-proof valve. The cell is housed within the casing, while the terminals and explosion-proof valve are located on the end face of the casing. One end face of the casing has a mounting hole into which the terminals are fixed for electrical connection to the cell. Before the explosion-proof valve ruptures due to thermal runaway, the increased internal pressure in a cylindrical battery causes the casing to deform. Furthermore, due to the lower structural strength at the mounting hole, deformation is highly likely to occur on the end face of the casing with the mounting hole, causing the terminals to loosen from the casing, affecting the reliability of the terminal installation, and potentially even causing the terminals to detach from the casing and fly out under gas pressure impact. Summary of the Invention

[0004] The purpose of this invention is to disclose a battery and an electrical device that can prevent the first wall of the casing from deforming during battery thermal runaway, thereby preventing the electrode terminals from detaching from the casing and flying out.

[0005] To achieve the above objectives, a first aspect of the present invention discloses a battery comprising: The shell has a receiving cavity inside, and the shell has a first wall with a first through hole that communicates with the receiving cavity. The battery cell is housed within the receiving cavity; Electrode terminals, at least partially passing through the first through hole and fixed to the first wall; The first current collector is disposed in the receiving cavity and between one end face of the battery cell and the electrode terminal. The electrode terminal is electrically connected to the battery cell through the first current collector. The first insulating member is at least partially located on the side of the first wall facing the receiving cavity, and the first insulating member is located on the side of the first current collector away from the battery cell. The first insulating member is connected to the first current collector to form an isolation cavity. The isolation cavity is configured such that when the first current collector squeezes the first insulating member, its isolation receiving cavity is separated from the first wall.

[0006] As an optional implementation, the circumferential edges of the first insulating member and the first current collector are connected by a concave-convex structure to form an isolation cavity between the first insulating member and the first current collector.

[0007] As an optional implementation, the first current collector includes a body portion, a flange, and a protruding edge. The body portion is disposed between one end face of the battery cell and an electrode terminal. The flange is located at the circumferential edge of the body portion and extends toward the first insulating member. The protruding edge is disposed at the end of the flange away from the body portion. The first insulating member has a groove on the side facing the first current collector, and the protruding edge is at least partially located in the groove.

[0008] As an alternative implementation, the protruding edge extends radially outward from the end of the flange near the first insulator; the surface of the groove facing the first current collector is an inclined surface, and the radially outer side of the inclined surface is farther away from the protruding edge than the radially inner side of the inclined surface.

[0009] As an optional implementation, the body is provided with a notch, which is located at the connection between the body and the flange.

[0010] As an optional implementation, the thickness of the protruding edge is greater than the thickness of the body.

[0011] As an alternative implementation, the battery includes a sealing assembly disposed between the electrode terminals and the first wall.

[0012] As an optional implementation, the electrode terminal includes a first connecting portion disposed in the receiving cavity, a portion of the first insulating member sandwiched between the first connecting portion and the first wall, and the first connecting portion is fixedly connected to the first current collector, the first current collector, the first insulating member and the electrode terminal forming an isolation cavity.

[0013] As an optional implementation, the other end of the housing is provided with an opening, and a cover plate is provided at the opening; the receiving cavity is provided with a second current collector, which is located between the other end face of the battery cell and the cover plate, and the cover plate is electrically connected to the battery cell through the second current collector; the cover plate is provided with a liquid injection hole and a pressure relief component.

[0014] A second aspect of the present invention discloses an electrical device comprising: the battery described above.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes the cooperation of a first current collector and a first insulating component to form an isolation cavity. When battery thermal runaway causes the cell to expand axially toward the first wall, and / or the gas pressure inside the cavity increases, the force can be directly applied to the first current collector, causing it to press tightly against the first insulating component. That is, the cell, the first current collector, the first insulating component, and the first wall sequentially abut against each other, forming a relatively sealed isolation cavity between the first current collector and the first insulating component. This isolation cavity isolates the first wall from the cavity, preventing the axial expansion force of the cell and / or the gas pressure inside the cavity from directly acting on the first wall. Thus, during battery thermal runaway, deformation of the first wall of the casing can be avoided, thereby preventing the electrode terminals from detaching from the casing and flying out. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the battery structure according to an embodiment of the present invention; Figure 2 This is an exploded view of the battery according to an embodiment of the present invention; Figure 3 This is an axial cross-sectional view of the battery according to an embodiment of the present invention; Figure 4 yes Figure 3 Enlarged view of point A in the middle; Figure 5 This is an axial sectional view of the assembly of the first current collector, electrode terminal and first insulating component according to an embodiment of the present invention; Figure 6 yes Figure 5 Enlarged view of point B in the middle; Figure 7 This is a schematic diagram of the first current collector, electrode terminal, and first insulating component in an unassembled state according to an embodiment of the present invention. Figure 8 This is a schematic diagram of the structure of the first current collector according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the electrode terminal insulation assembly according to an embodiment of the present invention; Figure 10 yes Figure 9 Enlarged view of point C in the middle; Figure 11 This is a schematic diagram of the structure of the first current collector being attached to the first insulating member according to an embodiment of the present invention; Figure 12 This is an axial cross-sectional view of the negative electrode side of the battery according to an embodiment of the present invention; Figure 13 This is a schematic diagram of the structure of the electrical device according to an embodiment of the present invention.

[0018] Explanation of key figure labels: 1. Housing; 11. Receiving cavity; 12. First wall; 121. First through hole; 13. Opening; 2. Battery cell; 3. Electrode terminal; 31. First connecting part; 32. Second connecting part; 33. Transition part; 34. Positioning groove; 4. First current collector; 41. Body part; 411. Score; 412. Positioning protrusion; 42. Flange; 43. Protruding edge; 5. First insulating component; 51. Groove; 6. Isolation cavity; 7. Cover plate; 71. Liquid injection hole; 72. Pressure relief assembly; 8. Second current collector; 9. Sealing assembly; 10. Second insulating component; 100. Battery; 200. Electrical device. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In this invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0021] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0022] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0023] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0024] The technical solution of the present invention will be further described below with reference to the embodiments and accompanying drawings.

[0025] Please see Figure 1 As shown in the figure, this application provides a battery 100. The battery may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc., and this application is not limited to these. The battery may be cylindrical, flat, cuboid, or other shapes, and this application is not limited to these. In this application, a cylindrical battery is used as an example for illustration. It has advantages such as high energy density and power density, high operating voltage, light weight, small size, long cycle life, good safety, and environmental friendliness. It has broad application prospects in portable electrical appliances, power tools, large-scale energy storage, and electric transportation power supplies. The structure of the battery 100 will be described in detail below with reference to the accompanying drawings. In the description, when referring to the direction of the battery 100 and its internal components, the direction is indicated by... Figure 3 As shown, the Z-axis is the axial direction, the X-axis is the radial direction, and the radial direction is not a single direction, but rather... Figure 3 In the plane perpendicular to the Z direction where the X direction is located, any direction line passing through the center of the circle belongs to the radial direction.

[0026] See Figures 1 to 3 The battery 100 includes a housing 1, a cell 2, and electrode terminals 3. The housing 1 has a receiving cavity 11 and a first wall 12. The first wall 12 has a first through hole 121 that communicates with the receiving cavity 11.

[0027] As an example, the housing includes a shell portion and an end cap, the shell portion having an opening 13, and the end cap for closing the opening 13. The shell portion is a component used to fit the end cap to form an internal receiving cavity 11 of a cylindrical battery cell, the formed receiving cavity 11 being used to accommodate the cell 2, electrolyte, and other components.

[0028] The casing and end cap can be separate components. For example, an opening 13 can be provided on the casing, and the end cap can be used to close the opening 13 to form a battery receiving cavity 11.

[0029] The shell can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0030] The shape of the end cap can be adapted to the shape of the casing to fit the casing. The material of the end cap can be the same as or different from that of the casing. Optionally, the end cap can be made of a material with a certain degree of hardness and strength (such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.), so that the end cap is not easily deformed when subjected to compression and impact, giving the battery higher structural strength and improving reliability.

[0031] The end caps are attached to the shell by welding, bonding, snap-fitting, or other means.

[0032] The shell portion may be open at one end or open at both ends. In some examples, the shell portion may be a structure open at one end, with one end cap fitting over the shell portion. In other examples, the shell portion may be a structure open at both ends, with two end caps fitting over the two openings 13 of the shell portion respectively.

[0033] The first wall 12 can be a shell or an end cap, and this application does not limit it.

[0034] The receiving cavity 11 extends axially, and the first wall 12 is located at one axial end of the housing 1. The first through hole 121 axially penetrates the first wall 12 to communicate with the receiving cavity 11. Generally, the first through hole 121 is located in the middle region of the first wall 12 to ensure the overall structural strength of the first wall 12 and to facilitate the installation of the electrode terminals 3 and the connection between the electrode terminals 3 and components such as the battery cell 2. Of course, in practical applications, the position of the first through hole 121 can be adjusted according to specific operating conditions.

[0035] The battery cell 2 is disposed in the receiving cavity 11. The battery cell 2 includes a positive electrode sheet, a negative electrode sheet, and a separator. The separator is disposed between the positive electrode sheet and the negative electrode sheet. The battery cell 2 is formed by stacking the positive electrode sheet, separator, and negative electrode sheet in sequence. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The current collector without the positive active material layer protrudes from the current collector with the positive active material layer. The current collectors without the positive active material layer are stacked to form the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector. The current collector without the negative active material layer protrudes from the current collector with the negative active material layer. The current collectors without the negative active material layer are stacked to form the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, etc. The separator can be made of PP (polypropylene) or PE (polyethylene), etc.

[0036] In some embodiments, the receiving cavity 11 of the housing 1 also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The type of electrolyte can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0037] Liquid electrolytes include electrolyte salts and solvents.

[0038] In some embodiments, the electrolyte salt may 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 dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0039] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl 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 may also be an ether solvent. Ether solvents may 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, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0040] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0041] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0042] As an example, polymer solid electrolytes can be polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0043] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0044] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0045] Furthermore, the battery cell can be a wound structure or a stacked structure, and the embodiments of this application are not limited to these. In this application, a wound structure, i.e., a wound core structure, is used as an example for explanation. The central axis area of ​​the wound core structure is hollow, and the distance between the outer periphery of the wound core structure and the shell 1 is set to facilitate the flow of electrolyte and ensure good insulation between the battery cell 2 and the shell 1. At least one end of the axial direction of the battery cell 2 is provided with a tab, which includes a first tab and a second tab. One of the first tab and the second tab is a positive tab, and the other is a negative tab. The first tab and the second tab can be provided at the same end of the axial direction of the battery cell 2, or the first tab can be provided at one end of the axial direction of the battery cell 2, and the second tab can be provided at the other end of the axial direction of the battery cell 2. This embodiment is described with the first tab and the second tab respectively provided at both ends of the axial direction of the battery cell 2.

[0046] The first electrode tab is electrically connected to the electrode terminal 3. The electrode terminal 3 is a pole post structure, at least partially passing through the first through hole 121 and fixed to the first wall 12. The electrode terminal 3 is insulated from the first wall 12. One end of the electrode terminal 3 is located in the receiving cavity 11 to electrically connect to the first electrode tab of the battery cell 2, and the other end of the electrode terminal 3 passes through the first through hole 121 to draw out the electricity from the battery cell 2 through the electrode terminal 3.

[0047] Since the tabs of the battery 100 are generally of a full-tab or multi-tab structure, in order to ensure that the current in the first tab of the full-tab or multi-tab structure is evenly collected to the electrode terminal 3, thereby ensuring uniform current distribution and reducing contact resistance, the battery 100 of this embodiment also includes a first current collector 4. (See also...) Figure 3 and Figure 4 The first current collector 4 is disposed in the receiving cavity 11, and is located between one end face of the battery cell 2 and the electrode terminal 3. The electrode terminal 3 is electrically connected to the battery cell 2 through the first current collector 4. The first current collector 4 is disposed at one axial end of the battery cell 2 with a first tab. One end face of the first current collector 4 is electrically connected to the first tab of the battery cell 2, and the other end face of the first current collector 4 is electrically connected to the electrode terminal 3, so as to uniformly lead the current from the first tab of the battery cell 2 to the electrode terminal 3 through the first current collector 4.

[0048] During operation, the battery 100 generates heat and is prone to thermal runaway. During this process, on one hand, the air pressure inside the housing 11 increases, directly impacting the first wall 12. Because the first wall 12 has a first through-hole 121, its structural strength is reduced, making it susceptible to deformation under pressure, especially around the through-hole 121. On the other hand, the cell 2 expands axially, and the resulting expansion force acts on the electrode terminal 3 via the first current collector 4, pushing it axially outward from the housing 1. The combined effect of the reduced structural strength of the first wall 12 and the outward expansion force on the electrode terminal 3 easily leads to loosening of the electrode terminal 3 at the first wall 12. This not only affects the reliability of the electrode terminal 3 installation but, with the intensification of thermal runaway, can easily cause the electrode terminal 3 to detach from the housing 1 and fly out.

[0049] To solve the above problems, please refer to Figure 3 and Figure 4 The battery 100 in this embodiment further includes a first insulating member 5. The first insulating member 5 is at least partially located on the side of the first wall 12 facing the receiving cavity 11, and the first insulating member 5 is located on the side of the first current collector 4 away from the cell 2. The first insulating member 5 is connected to the first current collector 4 to form an isolation cavity 6. The isolation cavity 6 is configured such that when the first current collector 4 squeezes the first insulating member 5, it isolates the receiving cavity 11 from the first wall 12.

[0050] The first insulating member 5 is made of insulating material such as plastic and has high temperature resistance to prevent it from melting during thermal runaway of the battery 100. The first insulating member 5 is fixed to the side of the first wall 12 facing the receiving cavity 11, and its side away from the first wall 12 is in contact with the first current collector 4. This contact means that at least the circumferential edge of the first insulating member 5 facing the first current collector 4 is in contact with the circumferential edge of the first current collector 4 facing the first insulating member 5, thereby forming an isolation cavity 6 through the first insulating member 5 and the first current collector 4. The isolation cavity 6 surrounds the electrode terminal 3, or the electrode terminal 3 can be one of the components forming the isolation cavity 6.

[0051] Under normal operating conditions of the battery 100, the contact between the first insulator 5 and the first current collector 4 can be non-tight, so that the isolation cavity 6 is a non-sealed chamber structure. During the thermal runaway of the battery 100, due to the increase in air pressure and the axial expansion of the cell 2, the first current collector 4 will be squeezed to press against the first insulator 5. At this time, it is necessary to ensure that the cell 2, the first current collector 4, the first insulator 5, and the first wall 12 abut against each other in sequence, so as to form a relatively sealed isolation cavity 6 between the first current collector 4 and the first insulator 5. Figure 11As shown), the isolation cavity 6 can isolate the first wall 12 and the receiving cavity 11, so that the air pressure in the receiving cavity 11 will not directly act on the first wall 12. Combined with the sequential contact of the battery cell 2, the first current collector 4, the first insulating member 5 and the first wall 12, the overall structural strength of the first wall 12 will be improved. In addition, the axial expansion force of the battery cell 2 is small and indirectly acts on the electrode terminal 3, thereby avoiding the deformation of the first wall 12, especially the periphery of the first through hole 121, so as to ensure the reliability of the assembly of the electrode terminal 3 and the first wall 12. Even if thermal runaway intensifies, the electrode terminal 3 can be prevented from detaching from the housing 1 and flying out.

[0052] In one or more alternative implementations, see Figure 5 and Figure 6 The circumferential edges of the first insulating member 5 and the first current collector 4 are connected by a concave-convex structure to form an isolation cavity 6 between the first insulating member 5 and the first current collector 4.

[0053] The concave-convex structure improves the tightness of the connection between the first insulator 5 and the first current collector 4 during the thermal runaway of the battery 100. Specifically, one of the first insulator 5 and the first current collector 4 has a concave portion on its circumferential edge, and the other has a convex portion on its circumferential edge. The concave and convex portions are matched and adapted to each other. During the thermal runaway of the battery 100, when the air pressure in the receiving cavity 11 squeezes the first current collector 4 toward the first insulator 5, the cooperation between the concave and convex portions can achieve the sealing of the isolation cavity 6 formed by the first current collector 4 and the first insulator 5. The air pressure in the isolation cavity 6 is relatively stable, which can prevent the deformation of the first wall 12 and the loosening or dislodgement of the electrode terminals 3.

[0054] In the first example, the circumferential edge of the end face of the first insulating member 5 facing the first current collector 4 is recessed away from the first current collector 4, and the circumferential edge of the end face of the first current collector 4 facing the first insulating member 5 is protruding towards the first insulating member 5, with the recess and protrusion adapted to each other. In the second example, the circumferential edge of the end face of the first insulating member 5 facing the first current collector 4 is protruding towards the first current collector 4, and the circumferential edge of the end face of the first current collector 4 facing the first insulating member 5 is recessed away from the first insulating member 5, with the recess and protrusion adapted to each other. In practical applications, either of these two examples can be chosen according to the operating conditions, and the specific structures of the recess and protrusion can also be diverse, as long as the recess and protrusion can ensure the relative sealing effect of the isolation cavity 6 during the thermal runaway of the battery 100, so as to keep the gas pressure inside the isolation cavity 6 relatively stable. This application's embodiments are described in detail using the first example.

[0055] See Figures 4 to 8The first current collector 4 includes a body portion 41, a flange 42, and a protruding edge 43. The body portion 41 is disposed between one end face of the battery cell 2 and the electrode terminal 3. The flange 42 is located at the circumferential edge of the body portion 41 and extends toward the first insulating member 5. The protruding edge 43 is disposed at the end of the flange 42 away from the body portion 41. The first insulating member 5 has a groove 51 on the side facing the first current collector 4, and the protruding edge 43 is at least partially located in the groove 51.

[0056] One end face of the battery cell 2, having a first tab, is electrically connected to one end face of the body portion 41, and the other end face of the body portion 41 is electrically connected to the electrode terminal 3. The circumferential edge of the body portion 41 protrudes towards the first insulating member 5 to form a flange 42. The end of the flange 42 away from the body portion 41 has a protruding edge 43 that mates with a groove 51. The protruding edge 43 is at least partially located within the groove 51; it can be partially or entirely located within the groove 51. Thus, the protruding edge 43 and the groove 51 form a concave-convex structure to improve the tightness of the connection between the first insulating member 5 and the first current collector 4 during thermal runaway of the battery 100. During the thermal runaway of battery 100, when the air pressure in the containment cavity 11 squeezes the first current collector 4 toward the first insulator 5, the cooperation between the protrusion 43 and the groove 51 can achieve the sealing of the isolation cavity 6 formed by the first current collector 4 and the first insulator 5. The air pressure in the isolation cavity 6 is relatively stable, which can prevent the first wall 12 from deforming and the electrode terminal 3 from loosening or falling out.

[0057] The protruding edge 43 extends radially outward from the end of the flange 42 near the first insulating member 5. The extension direction of the protruding edge 43 can be strictly radial, or it can be slightly inclined towards the first insulating member 5 while being radial. Based on this, a groove 51 is recessed at the circumferential edge of the end face of the first insulating member 5 facing the first current collector 4 away from the first current collector 4, and the position of the groove 51 corresponds to the position of the protruding edge 43.

[0058] The groove 51 can be a flat groove, meaning the bottom wall of the groove 51 away from the first current collector 4 is a plane parallel to the radial direction; the groove 51 can also be an inclined groove, meaning the bottom wall of the groove 51 away from the first current collector 4 is an inclined surface slightly inclined away from the first current collector 4 compared to being parallel to the radial direction. For the protrusion 43 and the groove 51, regardless of whether the structure is parallel to the radial direction or slightly inclined relative to the radial direction, the premise is to ensure the tight connection between the protrusion 43 and the groove 51 during the thermal runaway of the battery 100, so as to achieve the isolation effect of the isolation cavity 6. Furthermore, during the thermal runaway of the battery 100, the cooperation between the protrusion 43 and the groove 51 transfers the stress point of the first wall 12 to the circumferential edge of the first wall 12, rather than the periphery of the first through hole 121. This not only avoids deformation of the periphery of the first through hole 121, but also, in cooperation with the isolation cavity 6, significantly reduces the influence of air pressure on the electrode terminal 3, thereby ensuring the reliability of the electrode terminal 3 installed on the first wall 12.

[0059] In one or more alternative embodiments, the surface of the groove 51 facing the first collector 4 is an inclined surface, and the radially outer side of the inclined surface is farther away from the protrusion 43 than the radially inner side of the inclined surface.

[0060] The protruding edge 43 is a radially extending structure, and the groove 51 is a sloping groove structure, that is, the bottom wall of the groove 51 away from the first current collector 4 is a sloping surface, and the radially inner end of this sloping surface is closer to the first current collector 4 than the radially outer end. Thus, during the thermal runaway of the battery 100, the air pressure inside the receiving cavity 11 increases, and the air pressure and the axial expansion force of the cell 2 compress the first current collector 4 to press tightly against the first insulating member 5. During this process, the deformation of the first current collector 4 makes the protruding edge 43 press more tightly against the first insulating member 5, allowing it to adhere more firmly to the groove 51. Figure 11 As shown), the first insulating member 5 and the first current collector 4 are sealed together to form an isolation cavity 6. This not only effectively transfers the stress point of the first wall 12 to the position where the corresponding protrusion 43 and groove 51 are connected, reducing the stress on the periphery of the first through hole 121 and avoiding deformation of the periphery of the first through hole 121 of the first wall 12, but also the stable air pressure environment in the isolation cavity 6 can reduce the stress on the electrode terminal 3, thereby ensuring the reliability of the electrode terminal 3 installed at the first through hole 121 and preventing the electrode terminal 3 from detaching from the first wall 12 and flying out during the thermal runaway of the battery 100.

[0061] For the inclined structure of the groove 51, its inclination angle is generally less than 15°. Within this angle range, the sealing effect of the first insulating member 5 and the first current collector 4 under the inclined structure can be guaranteed. If the inclination angle is too large, the deformation of the first current collector 4 is insufficient to fill the groove 51 with the protrusion 43, so that the protrusion 43 and the groove 51 cannot be tightly connected, resulting in a large gap at the connection between the protrusion 43 and the groove 51. This affects the formation of a relatively sealed environment in the isolation cavity 6, causing the air pressure in the isolation cavity 6 to gradually increase with the increase of the air pressure in the receiving cavity 11, and acting on the first wall 12 on the periphery of the first through hole 121 and the electrode terminal 3. This may lead to the risk that the electrode terminal 3 is not securely assembled with the first wall 12, or even that the electrode terminal 3 is detached from the first wall and flies out. For example, the inclination angle of the inclined surface of the groove 51 can be 1°, 3°, 5°, 7°, 9°, 11°, 13°, 15°, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0062] Furthermore, see Figure 6 The thickness of the protruding edge 43 is greater than the thickness of the body portion 41. The protruding edge 43 is thicker than the body portion 41, and the thickness of the protruding edge 43 can be comparable to the thickness of the flange 42, both of which are greater than the thickness of the body portion 41. Thus, during the thermal runaway of the battery 100, the gas pressure inside the receiving cavity 11 increases, and the gas pressure and the axial expansion force of the cell 2 compress the first current collector 4 to press against the first insulating member 5. Figure 11 As shown), during this process, the deformation position of the first collector 4 is at the connection between the flange 42 and the body 41, so as to avoid the deformation of the protruding edge 43 from affecting the tightness of the fit between the protruding edge 43 and the groove 51.

[0063] Wherein, the thickness of the protruding edge 43 and the thickness of the body 41 refer to the axial dimensions ( Figure 3 As shown in the Z direction), the thickness of flange 42 is the radial dimension ( Figure 3 (shown in the X direction). For example, the thickness of the protruding edge 43 and the thickness of the flange 42 can be selected to be ≥0.3mm, and the thickness of both is ≥1.5 times the thickness of the body portion 41, so as to ensure the structural strength of the protruding edge 43 and the flange 42, so that the deformation occurs at the circumferential edge of the body portion 41, that is, at the bend of the body portion 41 near the flange 42, so that during the thermal runaway of the battery 100, the deformation at the circumferential bend of the body portion 41 can be used to achieve a tight fit between the protruding edge 43 and the groove 51.

[0064] Also see Figure 8 The main body 41 is provided with a notch 411, which is located at the connection between the main body 41 and the flange 42. The notch 411 can be located along the entire circumference of the connection between the main body 41 and the flange 42, or it can be provided in segments along the circumference. In the segmented spacing structure, the segments can be evenly spaced, non-uniformly spaced, or non-equal in length. During the thermal runaway of the battery 100, the air pressure inside the cavity 11 increases, and the air pressure and the axial expansion force of the cell 2 compress the first current collector 4 to adhere tightly to the first insulating member 5. Figure 11 As shown), the deformation of the first collector 4 is concentrated at the notch 411, that is, at the connection between the flange 42 and the body 41, which is prone to deformation, so as to avoid the deformation of the protruding edge 43 and affect the tightness of the fit between the protruding edge 43 and the groove 51.

[0065] It is worth noting that the varying thicknesses of the different parts of the first current collector 4 and the inclusion of the notch 411 are designed to concentrate the deformation of the first current collector 4 during thermal runaway of the battery 100 at the connection between the body 41 and the flange 42, thus preventing deformation of the protruding edge 43 from affecting the tightness of the fit between the protruding edge 43 and the groove 51. In practical applications, either the thickness variation or the notch 411 can be chosen, or both can be used to further ensure that the deformation of the first current collector 4 occurs at the connection between the body 41 and the flange 42.

[0066] In addition, the mating point between the first current collector 4 and the first insulator 5 is chamfered. For example, the inner and outer radial sides of the groove 51 are chamfered, and the inner and outer radial sides of the convex edge 43 are chamfered. The chamfering can prevent burrs from being generated at the corners and edges of the groove 51 and the convex edge 43, which would affect the tightness of the fit between the convex edge 43 and the groove 51.

[0067] The size of the chamfer is not specifically required and can be set according to the actual working conditions. For example, the chamfer radius can be ≥0.3mm to ensure a smooth, rounded transition. Of course, this is just an example; in actual applications, whether to set a chamfer, the location of the chamfer, and the size of the chamfer will depend on the specific requirements.

[0068] See Figure 5 , Figure 9 and Figure 10 The electrode terminal 3 includes a first connecting part 31, which is disposed in the receiving cavity 11. A portion of the first insulating member 5 is sandwiched between the first connecting part 31 and the first wall 12, and the first connecting part 31 is fixedly connected to the first current collector 4. The first current collector 4, the first insulating member 5 and the electrode terminal 3 form an isolation cavity 6.

[0069] One end of the electrode terminal 3 is provided with a first connecting portion 31, which is disposed in the receiving cavity 11. The end of the electrode terminal 3 away from the first connecting portion 31 extends through the first through hole 121. The end face of the first connecting portion 31 facing the first current collector 4 is electrically connected to the first current collector 4, and the end face of the first connecting portion 31 away from the first current collector 4 abuts against the first insulating member 5 against the first wall 12, so as to achieve insulation between the first connecting portion 31 and the first wall 12. Thus, the isolation cavity 6 is formed by the first current collector 4, the first insulating member 5 and the electrode terminal 3.

[0070] Under normal operating conditions of the battery 100, the contact between the first insulator 5 and the first current collector 4 can be non-tight, so that the isolation cavity 6 formed by the first current collector 4, the first insulator 5, and the electrode terminal 3 is a non-sealed chamber structure. During the thermal runaway of the battery 100, due to the increase in air pressure and the axial expansion of the cell 2, the first current collector 4 will be squeezed towards the first insulator 5 and pressed tightly. During this process, the connection between the flange 42 of the first current collector 4 and the body 41 deforms, so that the protruding edge 43 can be pressed more tightly against the groove 51 towards the first insulator 5. Figure 11 As shown), the first current collector 4, the first insulating member 5, and the electrode terminal 3 are sealed together to form an isolation cavity 6. This not only effectively transfers the stress point of the first wall 12 to the position where the corresponding protrusion 43 connects with the groove 51, reducing the stress on the periphery of the first through hole 121 and avoiding deformation of the periphery of the first through hole 121 of the first wall 12, but also the stable air pressure environment in the isolation cavity 6 can reduce the stress on the electrode terminal 3, thereby ensuring the reliability of the electrode terminal 3 installed at the first through hole 121 and preventing the electrode terminal 3 from detaching from the first wall 12 and flying out during the thermal runaway of the battery 100.

[0071] See Figures 5 to 7 , Figure 9 and Figure 10The electrode terminal 3 also includes a second connecting portion 32 and a transition portion 33, with the first connecting portion 31, the transition portion 33, and the second connecting portion 32 connected sequentially. The first connecting portion 31 has a positioning groove 34 on the side facing the first current collector 4, and the first current collector 4 has a positioning protrusion 412 on one end face facing the first connecting portion 31. The positioning protrusion 412 protrudes from the side of the body portion 41 facing the first connecting portion 31, and the positioning protrusion 412 and the positioning groove 34 are correspondingly fitted and welded together. The end face of the first current collector 4 away from the positioning protrusion 412 is welded to the first electrode tab of the battery cell 2. The transition portion 33 passes through the first through hole 121, and one end of the transition portion 33 extending axially out of the first through hole 121 to the outside of the housing 1 is connected to the second connecting portion 32. Thus, the current from the first electrode tab of the battery cell 2 is conducted to the second connecting portion 32 via the body portion 41, the first connecting portion 31, and the transition portion 33.

[0072] The transition portion 33 is radially recessed relative to the first connecting portion 31 and the second connecting portion 32. Specifically, the radial dimensions of both the first connecting portion 31 and the second connecting portion 32 are larger than the radial dimension of the transition portion 33. The radial dimension of the transition portion 33 is smaller than the radial dimension of the first through hole 121. Thus, the electrode terminal 3 has an "I"-shaped structure, preventing it from detaching from the first through hole 121 under normal operating conditions.

[0073] The electrode terminal 3 passes through the first through hole 121 and is insulated and sealed to the first wall 12. Specifically, the first connecting portion 31 is insulated from the first wall 12, the second connecting portion 32 is insulated from the first wall 12, and the transition portion 33 is insulated and sealed to the wall of the first through hole 121. This insulated and sealed structure includes a first insulating element 5, a sealing assembly 9, and a second insulating element 10. One of the first insulating element 5 and the second insulating element 10 can be made of plastic, or both can be made of plastic, providing good insulation. The first insulating element 5 is located between the first connecting portion 31 and the first wall 12 to insulate the first wall 12 from the first connecting portion 31. The sealing assembly 9 is located between the electrode terminal 3 and the first wall 12. The sealing assembly 9 can be a sealing ring structure, fitted around the outer periphery of the transition portion 33 and extending towards the first connecting portion 31 towards the first wall 12, thereby achieving a sealing and insulating effect between the electrode terminal 3 and the wall of the first through hole 121. The second insulating member 10 is disposed on the periphery of the second connecting portion 32 and extends between the second connecting portion 32 and the first wall 12 to ensure the insulation effect between the second connecting portion 32 and the first wall 12. In this way, the first insulating member 5, the sealing assembly 9 and the second insulating member 10 cooperate to achieve the electrode terminal 3 being sealed at the first through hole 121 and insulated from the first wall 12.

[0074] See Figures 1 to 3The battery 100 includes a first electrode and a second electrode with opposite polarities. The first electrode can be positive and the second electrode negative, or vice versa. The electrode terminal 3 can serve as the first electrode of the battery 100, and at least a portion of the casing 1 can serve as the second electrode. "At least a portion of the casing 1" means that the entire casing 1 can serve as the second electrode of the battery 100, or only a portion of the casing 1 can serve as the second electrode. The casing 1 includes a casing body, a first wall 12, and a second wall. The first wall 12 is located at one axial end of the casing body, and the second wall is located at the other axial end of the casing body, with the first wall 12 and the second wall facing each other. Since the electrode terminal 3 is insulated from the first wall 12, the first wall 12 can serve as the second electrode of the battery 100, the casing body can also serve as the second electrode of the battery 100, and the second wall can also serve as the second electrode of the battery 100. Considering that the first wall 12, the casing body, and the second wall are sequentially connected to form the casing 1, the entire casing 1 can be directly used as the second electrode of the battery 100. The first wall 12 can be connected to the shell body as an integral structure, or the first wall 12 can be a top cover welded to the shell body; the second wall can be connected to the shell body as an integral structure, or the second wall can be a cover plate 7 welded to the shell body.

[0075] Based on this, and considering ease of installation, when the first and second tabs are located at the same axial end of the battery cell 2, the second tab is electrically connected to the first wall 12; when the first and second tabs are located at opposite axial ends of the battery cell 2, i.e., the second tab is located at one axial end of the battery cell 2 near the second wall, the second tab is electrically connected to the second wall, and the electrical connection between the second tab and the second wall can be achieved through the second current collector 8.

[0076] For example, electrode terminal 3 serves as the positive electrode of battery 100; that is, the first tab of cell 2 is the positive electrode tab, the first current collector 4 is the positive current collector, and the negative electrode of battery 100 is located at the end opposite to electrode terminal 3. See also... Figure 2 and Figure 12 The other end of the housing 1 is provided with an opening 13, and a cover plate 7 is provided at the opening 13; the receiving cavity 11 is provided with a second current collector 8, which is located between the other end face of the battery cell 2 and the cover plate 7, and the cover plate 7 is electrically connected to the battery cell 2 through the second current collector 8; the cover plate 7 is provided with an injection hole 71 and a pressure relief component 72.

[0077] The end of the housing 1 facing away from the first wall 12 is open to form an opening 13, through which the battery cell 2 is installed in the receiving cavity 11. The end of the battery cell 2 away from the first electrode tab has a second electrode tab, which is the negative electrode tab. The second current collector 8 is the negative current collector plate, and the cover plate 7 and housing 1 are the negative terminal. The end face of the second current collector 8 facing the second electrode tab is welded to the second electrode tab, and the end face of the second current collector 8 facing away from the second electrode tab is welded to the cover plate 7.

[0078] The cover plate 7 is provided with an injection hole 71 and a pressure relief component 72, and the second current collector 8 is provided with an opening. Electrolyte is injected into the receiving cavity 11 through the injection hole 71 and wets the battery cell 2 during the flow process, thereby ensuring the permeation effect of the electrolyte without opening the first current collector 4. When the battery 100 thermally runs away and the gas pressure in the receiving cavity 11 becomes too high, the gas in the receiving cavity 11 is relieved through the pressure relief component 72 at the cover plate 7, without affecting the structural strength of the first current collector 4.

[0079] The pressure relief assembly 72 may include a grooved structure, which is thinned and installed on the cover plate 7. When the battery 100 experiences thermal runaway, the internal air pressure in the receiving cavity 11 breaks through the grooved structure to release pressure. The pressure relief assembly 72 may also include a pressure relief valve, which may be directly located at the injection port 71 or installed through an additional opening on the cover plate 7. When the battery 100 experiences thermal runaway, the internal air pressure in the receiving cavity 11 breaks through the pressure relief valve to release pressure. In practical applications, either the grooved structure or the pressure relief valve may be used, or both may be used.

[0080] See Figure 13 This application also provides an electrical device 200, which can be an electric vehicle, electric ship, aircraft, energy storage device, etc., powered by a battery device such as a battery pack or battery box, the battery device including at least one of the aforementioned batteries 100. Figure 13 Taking the car shown as an example of an electrical device 200, a battery device consisting of at least one battery 100 can be installed inside the part corresponding to the dashed box. The electrical device 200 also has all the technical effects of the battery 100 mentioned above, which will not be elaborated here.

[0081] The technical means disclosed in this invention are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications are also considered within the scope of protection of this invention.

Claims

1. A battery, characterized in that, include: The housing (1) has a receiving cavity (11) inside, and the housing (1) has a first wall (12) with a first through hole (121) on the first wall (12) communicating with the receiving cavity (11). Battery cell (2), wherein the battery cell (2) is disposed in the receiving cavity (11); Electrode terminal (3), which is at least partially inserted through the first through hole (121) and fixed to the first wall (12); The first current collector (4) is disposed in the receiving cavity (11) and is disposed between one end face of the battery cell (2) and the electrode terminal (3). The electrode terminal (3) is electrically connected to the battery cell (2) through the first current collector (4). The first insulating member (5) is at least partially located on the side of the first wall (12) facing the receiving cavity (11), and the first insulating member (5) is located on the side of the first current collector (4) away from the battery cell (2), and the first insulating member (5) is connected to the first current collector (4) to form an isolation cavity (6). The isolation cavity (6) is configured to isolate the receiving cavity (11) from the first wall (12) when the first current collector (4) presses the first insulating member (5).

2. The battery according to claim 1, characterized in that: The circumferential edges of the first insulating member (5) and the first current collector (4) are connected by a concave-convex structure to form the isolation cavity (6) between the first insulating member (5) and the first current collector (4).

3. The battery according to claim 2, characterized in that: The first current collector (4) includes a body (41), a flange (42) and a protruding edge (43). The body (41) is located between one end face of the battery cell (2) and the electrode terminal (3). The flange (42) is located on the circumferential edge of the body (41) and extends toward the first insulating member (5). The protruding edge (43) is located at one end of the flange (42) away from the body (41). The first insulating member (5) has a groove (51) on the side facing the first current collector (4). The protruding edge (43) is at least partially located in the groove (51).

4. The battery according to claim 3, characterized in that: The protruding edge (43) extends radially outward from the end of the flange (42) near the first insulating member (5); the surface of the groove (51) facing the first current collector (4) is an inclined surface, and the radial outer side of the inclined surface is farther away from the protruding edge (43) than the radial inner side of the inclined surface.

5. The battery according to claim 3 or 4, characterized in that: The body part (41) is provided with a groove (411), which is located at the connection between the body part (41) and the flange (42).

6. The battery according to claim 3 or 4, characterized in that: The thickness of the protruding edge (43) is greater than the thickness of the body portion (41).

7. The battery according to any one of claims 1-4, characterized in that: The battery (100) includes a sealing assembly (9) disposed between the electrode terminal (3) and the first wall (12).

8. The battery according to any one of claims 1-4, characterized in that: The electrode terminal (3) includes a first connecting part (31), which is disposed in the receiving cavity (11). A portion of the first insulating member (5) is sandwiched between the first connecting part (31) and the first wall (12), and the first connecting part (31) is fixedly connected to the first current collector (4). The first current collector (4), the first insulating member (5) and the electrode terminal (3) form the isolation cavity (6).

9. The battery according to any one of claims 1-4, characterized in that: The other end of the housing (1) is provided with an opening (13), and a cover plate (7) is provided at the opening (13); the receiving cavity (11) is provided with a second current collector (8), which is located between the other end face of the battery cell (2) and the cover plate (7), and the cover plate (7) is electrically connected to the battery cell (2) through the second current collector (8); the cover plate (7) is provided with an injection hole (71) and a pressure relief assembly (72).

10. An electrical appliance, characterized in that, include: The battery (100) according to any one of claims 1-9.

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