CN116632426A

CN116632426A - End cover assembly, energy storage device and electric equipment

Info

Publication number: CN116632426A
Application number: CN202310487632.4A
Authority: CN
Inventors: 熊永锋; 陈志雄; 洪纯省
Original assignee: Xiamen Hithium Energy Storage Technology Co Ltd
Current assignee: Xiamen Hithium Energy Storage Technology Co Ltd
Priority date: 2023-04-28
Filing date: 2023-04-28
Publication date: 2023-08-22

Abstract

The invention provides an end cover assembly, an energy storage device and electric equipment. The end cap assembly includes: the cover plate is provided with a first assembly hole; the first insulating piece comprises a body part arranged on one side of the cover plate in the thickness direction, and the body part is provided with a second assembly hole; the current collector is arranged on one side of the body part, which is opposite to the cover plate, and comprises a handle body part and a disc body part for connecting the electrode lugs, wherein the handle body part comprises a first connecting area, a second connecting area and a main body connected between the first connecting area and the second connecting area, the first connecting area is provided with a third assembly hole which is correspondingly communicated with the second assembly hole and the first assembly hole, and the second connecting area is connected with the disc body part; the pole comprises a pole body and a flange part connected to one end of the pole body, the pole body is arranged in the communicated assembly hole in a penetrating mode, and the flange part is propped against one side, opposite to the body, of the first connecting area. The body part and/or one side of the flange part facing the first connecting area is provided with a groove, the first connecting area is provided with a bulge corresponding to the groove, and the bulge is embedded in the corresponding groove.

Description

End cover assembly, energy storage device and electric equipment

Technical Field

The invention relates to the technical field of energy storage, in particular to an end cover assembly, an energy storage device and electric equipment.

Background

Secondary batteries, also called rechargeable batteries or secondary batteries, are batteries that can be used continuously by activating an active material by charging after the battery is discharged. The recyclable characteristic of the secondary battery gradually becomes a main power source of electric equipment, as the demand of the secondary battery gradually increases, the performance requirements of people on all aspects of the secondary battery are higher and higher, especially the requirements on the battery cycle performance, the energy density of the battery is an important parameter for ensuring the battery cycle performance, and the low energy density of unit volume can lead to low battery capacity and poor cycle performance.

Existing secondary batteries, such as cylindrical lithium ion batteries, are composed of an end cap assembly, an electrode assembly, and a cylindrical case. The actual production process is that an end cover component, an electrode component and a cylindrical shell are respectively manufactured firstly; then, respectively welding a pole post of the end cover assembly and a pole lug of the electrode assembly by using a metal adapter (i.e. a current collector); then the electrode assembly is put into a cylindrical shell; after the end cap assembly covers the opening of the cylindrical case, it is welded and sealed with the opening of the cylindrical case to form a basic structure of the secondary battery. However, the presence of the metal adapter makes the larger gap inside the secondary battery not effectively usable, which is an obstacle to further increasing the energy density of the secondary battery.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides the end cover assembly, the energy storage device and the electric equipment, when the end cover assembly is applied to the energy storage device, the current collector of the end cover assembly is folded, so that the space can be saved, and the energy density of the energy storage device can be improved.

To achieve the above object, in a first aspect, the present invention provides an end cap assembly comprising:

the cover plate is provided with first assembly holes penetrating through two opposite sides of the cover plate along the thickness direction;

the first insulating piece comprises a body part arranged on one side of the cover plate in the thickness direction, and second assembly holes penetrating through two opposite sides of the body part are formed in the thickness direction;

the current collector is arranged on one side of the body part, which is opposite to the cover plate, and comprises a disc body part and a handle body part which are connected, wherein the disc body part is used for connecting the electrode lugs, the handle body part comprises a first connecting area, a second connecting area and a main body connected between the first connecting area and the second connecting area, the first connecting area is provided with third assembly holes penetrating through two opposite sides of the first connecting area along the thickness direction, the third assembly holes, the second assembly holes and the first assembly holes are correspondingly communicated, and the second connecting area is connected with the disc body part;

The pole comprises a pole body and a flange part connected to one end of the pole body, the pole body is arranged in the third assembly hole, the second assembly hole and the first assembly hole in a penetrating manner, and the flange part is stopped against one side, opposite to the body, of the first connecting area;

the flange part is provided with a flange part, a body part and/or a flange part, wherein a groove is formed in one side of the body part and/or the flange part, which faces the first connecting area, a protrusion corresponding to the groove is arranged in the first connecting area, and the protrusion is embedded in the corresponding groove.

In an embodiment, the recess is formed on a side of the body facing the first connection area, the protrusion corresponding to the recess is formed on a side of the first connection area facing the body, and the protrusion forms a recess on a side of the first connection area facing away from the body.

In an embodiment, one side of the main body along a first direction is connected to the first connection region, the other side of the main body along the first direction is connected to the second connection region, and the first direction is parallel to a plane in which the first connection region is located;

the protrusion comprises at least one first sub-protrusion extending in a second direction, the first sub-protrusion extending at least from an edge of the first connection region in the second direction to a location of the first connection region covered by the flange portion, the second direction intersecting the first direction;

The groove comprises at least one first sub-groove, the first sub-grooves are in one-to-one correspondence with the first sub-protrusions, and each first sub-protrusion is embedded in a corresponding first sub-groove.

In one embodiment, the first sub-protrusion extends from an edge of the first connection region in the second direction to the third fitting hole.

In an embodiment, the projection further comprises at least one second sub-projection extending in the first direction, the orthographic projection of the second sub-projection on the first connection area at least partially coinciding with the orthographic projection of the flange portion on the first connection area;

the groove further comprises at least one second sub-groove, the second sub-grooves are in one-to-one correspondence with the second sub-protrusions, and each second sub-protrusion is embedded in a corresponding second sub-groove.

In an embodiment, the groove is also formed on a side of the flange portion facing the first connection region, a protrusion corresponding to the groove is formed on a side of the first connection region facing the flange portion, and the protrusion forms a recess on a side of the first connection region facing away from the flange portion;

The orthographic projection of the groove on the flange part on the body part is not overlapped with the groove on the body part.

In an embodiment, the groove is formed on a side of the flange portion facing the first connection region, the protrusion corresponding to the groove is formed on a side of the first connection region facing the flange portion, and the protrusion forms a recess on a side of the first connection region facing away from the flange portion.

the projection comprises at least one third sub-projection extending in a second direction, the third sub-projection extending at least from an edge of the first connection region in the second direction to a location of the first connection region covered by the flange portion, the second direction intersecting the first direction;

the groove comprises at least one third sub-groove, each third sub-groove extends from the peripheral wall of the flange part to the joint of the flange part and the column part, the third sub-grooves correspond to the third sub-protrusions one by one, and one end, close to the flange part, of each third sub-protrusion is embedded in one corresponding third sub-groove.

In an embodiment, the third sub-protrusion extends from an edge of the first connection region in the second direction to the third fitting hole.

In an embodiment, the projection further comprises at least one fourth sub-projection extending in the first direction, the orthographic projection of the fourth sub-projection on the first connection area at least partially coinciding with the orthographic projection of the flange portion on the first connection area;

the groove further comprises at least one fourth sub-groove, each fourth sub-groove extends from the peripheral wall of the flange part to the joint of the flange part and the column part, the fourth sub-grooves correspond to the fourth sub-protrusions one by one, and at least one end, close to the flange part, of each fourth sub-protrusion is embedded in the corresponding fourth sub-groove.

In an embodiment, the end cover assembly further comprises a sealing ring, the sealing ring is sleeved on the peripheral wall of the cylinder part, the sealing ring comprises a sealing ring body and a protruding part connected to the peripheral wall of the sealing ring body, the sealing ring body is located between the cylinder part and the cover plate, the protruding part extends from the joint of the sealing ring body along the radial direction of the third assembly hole away from the center of the third assembly hole, and the protruding part is located between the flange part and the cover plate.

In an embodiment, the first connection area is provided with a plurality of sub-protrusions, and the plurality of sub-protrusions are symmetrically arranged about the center of the third assembly hole;

and/or the depth of the groove is 0.3-1mm, the height of the protrusion is 0.3-1mm,

and/or the width of the protrusion and the groove is D1, the radius of the flange portion is D2, and the D1 and D2 satisfy the relation: d2 is less than or equal to 1/3 and D2-D1 is less than or equal to 2/3 and D2.

In a second aspect, the present invention provides an energy storage device comprising an end cap assembly as described in any one of the embodiments above.

In a third aspect, the present invention provides a powered device comprising an energy storage device as described above.

Compared with the prior art, the invention has the following beneficial effects: when the end cover assembly is applied to a battery cell of the energy storage device, the current collector is folded, so that space can be saved, the energy density of the battery cell can be improved, and the energy density of the energy storage device can be improved; furthermore, the body part of the first insulating part and/or the flange part of the pole and the first connecting area of the handle body part are in embedded fit through corresponding grooves and protrusions, the first connecting area is fixed on the body part by pressing the flange part, the first connecting area can be prevented from being warped, the flange part is tightly attached to the first connecting area, the axis of the column part of the pole is further overlapped or approximately overlapped with the axis of the plurality of communicated assembly holes, the column part can be directly penetrated into the plurality of communicated assembly holes at a position, the sealing effect of a sealing ring sleeved outside the column part is improved, and the leakage phenomenon of electrolyte from among the pole, the first insulating part and the cover plate is avoided; in addition, the body part and/or the flange part are/is matched with the first connecting area in an embedded manner through the protrusions and the corresponding grooves, so that a rotation stopping effect between the body part and the handle body part and/or between the pole and the handle body part can be realized, and the torsion resistance of the end cover assembly can be improved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is an application scenario diagram of an energy storage device provided by an embodiment of the present invention in user side energy storage.

Fig. 2 is a schematic perspective view of an end cap assembly according to one embodiment of the present invention in a flattened condition of the header.

FIG. 3 is a schematic plan view of the end cap assembly of FIG. 2 from another perspective.

FIG. 4 is a partially exploded perspective view of the end cap assembly of FIG. 2.

Fig. 5 is a schematic view of the end cap assembly of fig. 4 in an exploded perspective view from another perspective.

Fig. 6 is a further exploded isometric view of the end cap assembly of fig. 4.

Fig. 7 is a schematic view of the end cap assembly of fig. 6 in an exploded perspective view from another perspective.

FIG. 8 is a cross-sectional view of the end cap assembly of FIG. 2 taken along the direction A-A.

Fig. 9 is a schematic perspective view of the end cap assembly of fig. 2 in a collapsed condition of the current collector.

Fig. 10 is a schematic perspective view of the end cap assembly of fig. 9 from another perspective.

FIG. 11 is a cross-sectional view of the end cap assembly of FIG. 9 taken along the direction B-B.

FIG. 12 is a partially exploded perspective view of an end cap assembly according to another embodiment of the present invention.

Fig. 13 is a schematic exploded isometric view of the end cap assembly of fig. 12 from another perspective.

Fig. 14 is a schematic view of an assembled structure of the current collector, the post and the seal ring shown in fig. 12.

FIG. 15 is a cross-sectional view of the end cap assembly of FIG. 12 after assembly.

FIG. 16 is a cross-sectional view of the end cap assembly of FIG. 15 in another embodiment.

Reference numerals illustrate:

100-an energy storage device; 200-an electric energy conversion device; 300-first user load; 400-second user load;

1-an end cap assembly; 11-cover plate; 111-a first assembly hole; 112-a pressure relief vent; 1121-a first sink; 1122-a second sink; 113-a first positioning groove; 114-positioning holes; 12-a first insulator; 121-a body portion; 1211-fool-proof flanges; 122-a second assembly hole; 123-grooves; 1231-first sub-groove; 1232-second sub-groove; 124-a hollowed-out structure; 125-positioning columns; 126-rib section; 13-pole; 131-column part; 132-flange portion; 1321-third sub-groove; 1322-fourth sub-groove; 133-fitting part; 14-current collector; 141-a tray body; 1411-a first weld groove; 1412-second weld groove; 1413-a first via; 1414-a second via; 142-handle body; 1421-a first connection region; 1422-a second connection region; 1423-body; 1424-a third mounting hole; 1425-a first inflection region; 1426-a second inflection region; 1427-first stiffener; 1428-a second stiffener; 1429-fool-proof unfilled corners; 143-projections; 1431-a first sub-bump; 1432-a second sub-protrusion; 1433-a third sub-protrusion; 1434-fourth sub-protrusions; 15-an explosion-proof valve; 16-an explosion-proof valve protection sheet; 17-a sealing ring; 171-a seal ring body; 172-a protrusion; 18-a second insulator; 181-a first positioning block; 182-a second detent; 19-riveting pressing blocks.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

In order to facilitate understanding of the energy storage device provided by the embodiment of the present invention, some general knowledge in the energy storage technical field will be described below.

Because of the strong timeliness and space properties of energy required by people, in order to reasonably utilize the energy and improve the utilization rate of the energy, one energy form needs to be stored by one medium or equipment and then converted into another energy form, and the energy is released in a specific energy form based on future application. At present, the main way of generating green electric energy is to develop green energy sources such as photovoltaics, wind power and the like to replace fossil energy sources, the generation of the green electric energy at present generally depends on photovoltaics, wind power, water potential and the like, and wind energy, solar energy and the like generally have the problems of strong intermittence and large fluctuation, which can cause unstable power grid, insufficient peak electricity consumption, too much electricity consumption in valley, unstable voltage also can cause damage to the power, so that the problem of 'waste wind and waste light' is possibly caused by insufficient electricity consumption requirement or insufficient power grid acceptance, and the problem needs to be solved by depending on energy storage. The energy is converted into other forms of energy through physical or chemical means and is stored, the energy is converted into electric energy when needed and released, in short, the energy storage is similar to a large-scale 'charge pal', the electric energy is stored when the photovoltaic and wind energy are sufficient, and the stored electric power is released when needed.

Taking electrochemical energy storage as an example, the embodiment of the invention provides an energy storage device, wherein a chemical battery is arranged in the energy storage device, chemical elements in the chemical battery are mainly used as energy storage media, and the charge and discharge process is accompanied with chemical reaction or change of the energy storage media, namely, the electric energy generated by wind energy and solar energy is simply stored in the chemical battery, and the stored electric quantity is released for use when the use of external electric energy reaches a peak, or is transferred to a place with short electric quantity for use.

The existing energy storage (i.e. energy storage) application scene is wider, including aspects such as power generation side energy storage, electric network side energy storage, renewable energy grid-connected energy storage, user side energy storage and the like, the types of corresponding energy storage devices include:

(1) The large energy storage container applied to the energy storage scene at the power grid side can be used as a high-quality active and reactive power regulation power supply in the power grid, so that the load matching of electric energy in time and space is realized, the renewable energy consumption capability is enhanced, and the large energy storage container has great significance in the aspects of standby of a power grid system, relieving peak load power supply pressure and peak regulation and frequency modulation;

(2) The main operation modes of the small and medium-sized energy storage electric cabinet applied to the industrial and commercial energy storage scenes (banks, shops and the like) at the user side and the household small-sized energy storage box applied to the household energy storage scene at the user side are peak clipping and valley filling. Because of the large price difference of the electricity charge at the peak-valley position according to the electricity consumption requirement, after the energy storage equipment is arranged by a user, in order to reduce the cost, the energy storage cabinet/box is charged usually in the electricity price valley period; and in the peak period of electricity price, the electricity in the energy storage equipment is released for use, so that the purpose of saving electricity charge is achieved. In addition, in remote areas and areas with high occurrence of natural disasters such as earthquake, hurricane and the like, the household energy storage device is equivalent to the fact that a user provides a standby power supply for the user and the power grid, and inconvenience caused by frequent power failure due to disasters or other reasons is avoided.

Referring to fig. 1, an embodiment of the present invention is illustrated by taking a home energy storage scenario in a user side energy storage as an example, and an energy storage device 100 provided by the embodiment of the present invention is described. Of course, the energy storage device 100 provided in the embodiment of the present invention is not limited to the home energy storage scenario.

As shown in fig. 1, an embodiment of the present invention provides a household energy storage system, which includes an electric energy conversion device 200 (photovoltaic panel), a first user load 300 (street lamp), a second user load 400 (e.g. a household appliance such as an air conditioner), and the like, and an energy storage device 100, wherein the energy storage device 100 is a small-sized energy storage box and can be installed on an outdoor wall in a wall-hanging manner. In particular, the photovoltaic panel may convert solar energy into electric energy during the low electricity price period, and the energy storage device 100 is used to store the electric energy and supply the electric energy to the street lamp and the household appliances for use during the electricity price peak or supply the electric power during the power outage/power failure of the electric network.

It is understood that in embodiments of the present invention, the energy storage device 100 may include, but is not limited to, a battery cell, a battery module, a battery pack, a battery system, etc. The battery cell included in the energy storage device 100 may be a cylindrical battery. It should be noted that, the battery unit includes a case, an electrode assembly accommodated in the case, and an end cap encapsulated at an opening of the case, and the end cap may adopt the end cap assembly 1 provided by the embodiment of the present invention.

Referring to fig. 2 to 11, an end cap assembly 1 is provided according to an embodiment of the present invention, and is applied to a battery cell (not limited to a lithium ion secondary battery). The end cap assembly 1 may be used as a positive end cap of the battery cell or a negative end cap of the battery cell, which is not limited thereto.

Referring specifically to fig. 2 to 8, in an embodiment of the present invention, the end cap assembly 1 includes a cap plate 11, a first insulating member 12, a post 13, and a current collector 14. The cover plate 11 is provided with first fitting holes 111 penetrating through opposite sides thereof in the thickness direction. The first insulating member 12 includes a body portion 121 fixedly provided at one side (i.e., the side facing the inside of the battery cell) of the cap plate 11 in the thickness direction, and the body portion 121 is provided with second fitting holes 122 penetrating the opposite sides thereof in the thickness direction. The pole 13 includes a cylindrical portion 131 and a flange portion 132 connected to one end of the cylindrical portion 131. The current collector 14 is disposed on a side of the body 121 facing away from the cover plate 11, and the current collector 14 includes a connected tray portion 141 and a handle portion 142; the tray portion 141 has a welding area for welding a tab (not shown) of an electrode assembly (not shown) of a battery cell where the end cap assembly 1 is located; the handle body 142 includes a first connection region 1421, a second connection region 1422, and a main body 1423 connected between the first connection region 1421 and the second connection region 1422, the second connection region 1422 is connected to the tray body 141, the first connection region 1421 is located at one end of the handle body 142 away from the tray body 141, wherein the main body 1423 includes at least one bending region (hereinafter Wen Huiyou is described in detail) located at one side of the first connection region 1421 near the tray body 141, and the first connection region 1421 is provided with a third assembly hole 1424 penetrating through opposite sides thereof in a thickness direction, and the third assembly hole 1424, the second assembly hole 122, and the first assembly hole 111 are correspondingly communicated. Referring to fig. 6 to 8, in the embodiment of the invention, the cylindrical portion 131 is inserted into the corresponding third assembling hole 1424, the second assembling hole 122 and the first assembling hole 111 from the side of the handle body 142 facing away from the body 121, and the flange portion 132 is stopped against the side of the first connecting region 1421 facing away from the body 121. It should be noted that, the flange 132 and the first connection region 1421 are generally welded, so that, when the disc 141 is welded to the tab of the electrode assembly, the current collector 14 is electrically connected between the electrode assembly and the post 13, thereby enabling the electric power transmission of the electrode assembly. As shown in fig. 8, the end cap assembly 1 further includes a sealing ring 17, the sealing ring 17 is sleeved on the outer peripheral wall of the cylinder 131, and the sealing ring 17 is located between the cylinder 131 and the first insulating member 12, and between the cover plate 11, so as to play a sealing role, and prevent the leakage problem of the electrolyte of the battery cell.

Referring to fig. 9 to 11, in the embodiment of the invention, the current collector 14 (specifically, the handle body 142) may be folded at the folding area, so that the tray body 141 welded to the tab is aligned with the cover plate 11, the first insulating member 12 and the electrode assembly, and the cover plate 11 is used for sealing and welding the housing of the battery cell. That is, when the end cap assembly 1 provided in the embodiment of the present invention is applied to a battery cell, the current collector 14 is folded, so that the occupied space in the case can be saved, thereby facilitating the installation of a larger-sized electrode assembly in the case, and thus being helpful for improving the energy density of the battery cell.

Referring to fig. 3 to 5, and fig. 8 again, in an embodiment of the present invention, a groove is formed on a side of the body portion 121 and/or the flange portion 132 facing the first connection area 1421, the first connection area 1421 is provided with a protrusion 143 corresponding to the groove, and the protrusion 143 is embedded in the corresponding groove.

In the existing end cover assembly, the bending area of the handle body part of the current collector, which is close to the first connecting area, can generate upward acting force when being bent, but because the first connecting area of the handle body part is only fixed on the part connected with the pole and the first insulating piece, other parts of the first connecting area are not fixed and limited with the first insulating piece, other parts of the first connecting area are easy to be driven by the upward acting force to generate warping, so that the tightness is poor, and the risk of liquid leakage exists. In the end cap assembly 1 provided in the embodiment of the present invention, the body portion 121 and/or the flange portion 132 are in fit with the first connecting region 1421 through the protrusions 143 and the corresponding grooves, and the first connecting region 1421 is pressed and fixed to the body portion 121 by the flange portion 132, so that a fixed limit between the first connecting region 1421 and the first insulating member 12 is achieved, and therefore, the first connecting region 1421 is prevented from buckling, the flange portion 132 is tightly attached to the first connecting region 1421, and further, the axis of the cylinder portion 131 is overlapped or approximately overlapped with the axis of the plurality of connecting holes, that is, the cylinder portion 131 can be directly inserted into the plurality of connecting holes at a position, which is helpful for improving the sealing effect of the sealing ring 17 sleeved outside the cylinder portion 131, and avoiding leakage of electrolyte from between the pole 13, the first insulating member 12 and the cover plate 11. In addition, the body portion 121 and/or the flange portion 132 and the first connection region 1421 are in fit engagement with each other through the protrusions 143 and the corresponding grooves, so that a rotation stopping effect between the body portion 121 and the shank body portion 142 and/or between the pole 13 and the shank body portion 142 can be achieved, which is helpful for improving the torsion resistance of the end cap assembly 1.

Specifically, referring to fig. 4 to 8, in one embodiment of the present invention, a groove 123 is formed on a side of the body 121 facing the first connection area 1421, and the protrusion 143 corresponding to the groove 123 is formed on a side of the first connection area 1421 facing the body 121, wherein the protrusion 143 is recessed on a side of the first connection area 1421 facing away from the body 121. In this embodiment, the body portion 121 and the first connection area 1421 are in fit with each other through the protrusions 143 and the corresponding grooves 123, so that a rotation stopping effect between the body portion 121 and the handle body portion 142 can be achieved, and the first connection area 1421 is welded to the post 13, so that the post 13 is prevented from rotating relative to the first insulating member 12, and the torsion resistance of the end cap assembly 1 can be further improved. In addition, the protrusion 143 is configured to form a recess on a side of the first connection region 1421 facing away from the body 121, so that not only can manufacturing materials of the protrusion 143 be saved and costs be reduced, but also the overall thickness of the handle body 142 can be kept uniform, thereby facilitating integrated processing and forming.

As shown in fig. 4 to 8, in one embodiment of the present invention, one side of the main body 1423 along a first direction is connected to the first connection region 1421, and the other side of the main body 1423 along the first direction is connected to the second connection region 1422, wherein the first direction is parallel to a plane in which the first connection region 1421 is located. Specifically, in the examples of fig. 4 to 8, the current collector 14 is in a flattened state (i.e., no bending occurs), the handle body 142 is in a rectangular sheet shape, the second connection region 1422 is located at one end of the handle body 142 in the length direction and is connected to the tray body 141, and the first connection region 1421 is located at the other end of the handle body 142 in the length direction. That is, in the example of fig. 4 to 8, the first direction is the longitudinal direction of the shank body 142. In other embodiments, the first direction may be a width direction of the flattened handle body 142, which is not limited thereto.

The projection 143 includes at least one first sub-projection 1431 extending in a second direction, and the first sub-projection 1431 extends at least from an edge of the first connection region 1421 in the second direction to a portion of the first connection region 1421 covered by the flange portion 132, the second direction intersecting the first direction. In the example of fig. 4 to 8, the second direction is the width direction of the shank body 142 in the flattened state, that is, the first direction and the second direction are perpendicular to each other. In other embodiments, the second direction may also be a direction that forms an acute angle with the first direction, that is, the second direction is not perpendicular to the first direction, which is not limited. Accordingly, the groove 123 includes at least one first sub-groove 1231 extending along the second direction, the first sub-grooves 1231 are in one-to-one correspondence with the first sub-protrusions 1431, and each of the first sub-protrusions 1431 is embedded in a corresponding one of the first sub-grooves 1231 (see fig. 8). In this embodiment, by providing the first sub-protrusion 1431 to extend from the edge of the first connection region 1421 in the second direction (i.e., the width direction of the handle body 142) to the portion of the first connection region 1421 covered by the flange 132, it is ensured that the flange 132 covers at least part of the recess formed by the first sub-protrusion 1431 on the side of the first connection region 1421 facing away from the body 121, so as to ensure that the flange 132 can directly perform a pressing action on the first sub-protrusion 1431, so that the first sub-protrusion 1431 is embedded in the corresponding first sub-recess 1231, thereby realizing fixation between the handle body 142 and the body 121, and preventing the handle body 142 from buckling and improving the sealing performance of the sealing ring 17. In other embodiments, the first sub-protrusion 1431 may extend from the edge of the first connection region 1421 in the second direction toward the flange 132, but the first sub-protrusion 1431 is not covered by the flange 132, and in this case, after the first sub-protrusion 1431 is in a snap fit with the corresponding first sub-groove 1231, the first sub-protrusion 1431 and the corresponding first sub-groove 1231 may be fixed by a force caused by pressing the flange 132 against the entire first connection region 1421, so as to achieve a warpage preventing effect.

It will be appreciated that the larger the area of the flange 132 covering the recess formed by the first sub-protrusion 1431, the larger the pressing effect of the flange 132, the better the fixing effect between the handle body 142 and the body 121, and the better the warpage preventing effect of the handle body 142 and the sealing effect of the sealing ring 17. Preferably, in the example of fig. 4 to 8, the first sub-protrusion 1431 extends from an edge of the first connection region 1421 in the second direction to the third fitting hole 1424, that is, the recess formed correspondingly to the first sub-protrusion 1431 communicates with the third fitting hole 1424. In this embodiment, the flange 132 may cover the recess formed by the first sub-protrusion 1431 with the largest area, so that the first sub-protrusion 1431 may be pressed with the largest pressing effect, so that the fixing effect between the handle body 142 and the body 121 is the best, and the warpage preventing effect on the handle body 142 and the sealing effect of the sealing ring 17 are also the best.

Further, as shown in fig. 4 to 7, in one embodiment of the present invention, the protrusion 143 further includes at least one second sub-protrusion 1432 extending along the first direction (i.e., the length direction of the handle body 142), and the orthographic projection of the second sub-protrusion 1432 on the first connection region 1421 is at least partially overlapped with the orthographic projection of the flange 132 on the first connection region 1421, that is, the flange 132 covers at least a partial recess formed on the side of the second sub-protrusion 1432 facing away from the body 121 of the first connection region 1421; accordingly, the groove 123 further includes at least one second sub-groove 1232, the second sub-grooves 1232 are in one-to-one correspondence with the second sub-protrusions 1432, and each of the second sub-protrusions 1432 is embedded in a corresponding one of the second sub-grooves 1232. In this embodiment, by adding the second sub-protrusion 1432 extending along the first direction and at least partially covered by the flange 132 to the first connection region 1421, the corresponding second sub-groove 1232 is added to the body 121, so that not only the first sub-protrusion 1431 and the corresponding first sub-groove 1231 but also the second sub-protrusion 1432 and the corresponding second sub-groove 1232 can be engaged with each other, which is helpful for improving the fixing effect between the first connection region 1421 and the body 121, and thus improving the warpage preventing effect of the handle 142 and the sealing effect of the sealing ring 17.

It will be appreciated that in the example of fig. 4 to 7, the extension length of the second sub-protrusion 1432 may be variously adjusted according to the size of the flange portion 132, so long as the second sub-protrusion 1432 does not exceed the first connection region 1421. Preferably, similar to the first sub-protrusion 1431, the second sub-protrusion 1432 extends to the third assembling hole 1424, that is, the recess formed by the second sub-protrusion 1432 is also connected to the third assembling hole 1424, so that the flange 132 can perform the maximum pressing function on the first sub-protrusion 1431 and the second sub-protrusion 1432 at the same time, which is helpful for further improving the fixing effect between the handle body 142 and the body 121, the anti-warping effect on the handle body 142, and the sealing effect of the sealing ring 17.

In the embodiment of the present invention, the number of the first sub-protrusions 1431 and the second sub-protrusions 1432 provided on the first connection region 1421 may be one or more, and the body 121 may be provided with one or more first sub-grooves 1231 corresponding to the first sub-protrusions 1431 and one or more second sub-grooves 1232 corresponding to the second sub-protrusions 1432, respectively. Preferably, in the embodiment of the present invention, the first connection region 1421 is provided with a plurality of first sub-protrusions 1431 and a plurality of second sub-protrusions 1432, the body portion 121 is correspondingly provided with a plurality of first sub-grooves 1231 and a plurality of second sub-grooves 1232, the plurality of first sub-protrusions 1431 are correspondingly matched with the plurality of first sub-grooves 1231 one by one, and the plurality of second sub-protrusions 1432 are correspondingly matched with the plurality of second sub-grooves 1232 one by one, so as to enhance the fixing effect between the handle body portion 142 and the body portion 121, the warpage preventing effect of the handle body portion 142, and the sealing effect of the sealing ring 17. Further preferably, the first sub-protrusions 1431 and the second sub-protrusions 1432 are symmetrically disposed about the center of the third fitting hole 1424, which helps to improve uniformity of the fixing effect between the handle body 142 and the body 121, uniformity of the warpage preventing effect on the handle body 142, and uniformity of the sealing effect of the seal ring 17. In the examples of fig. 4 to 8, the number of the first sub-protrusions 1431 and the second sub-protrusions 1432 is two, and the first connection region 1421 is provided with the protrusions 143 having a cross shape and symmetrically arranged with respect to the center of the third assembly hole 1424.

In other embodiments, the first connection region 1421 may be configured with two first sub-protrusions 1431 or two second sub-protrusions 1432 only symmetrically with respect to the center of the third assembly hole 1424, and the body 121 may be correspondingly configured with two first sub-grooves 1231 or two second sub-grooves 1232, where the two first sub-protrusions 1431 or the two second sub-protrusions 1432 are in a shape of a straight line.

In other embodiments, the first connecting region 1421 may further include a plurality of sub-protrusions extending along different radial directions of the third assembling hole 1424, and the body 121 may further include a plurality of sub-grooves, which is not limited thereto.

Referring to fig. 12 to 15, in another embodiment of the present invention, a groove is formed on a side of the flange portion 132 facing the handle portion 142, and the protrusion 143 corresponding to the groove is formed on a side of the first connection region 1421 facing the flange portion 132, wherein the protrusion 143 forms a recess on a side of the first connection region 1421 facing away from the flange portion 132. In this embodiment, the flange 132 and the first connection area 1421 are in fit engagement with each other through the protrusions 143 and the corresponding grooves, so that a rotation stopping effect between the flange 132 and the handle 142 can be achieved, the pole 13 can be prevented from rotating relative to the current collector 14, and the torsion resistance of the end cap assembly 1 can be further improved. Similarly, the protrusion 143 is configured to form a recess on a side of the first connection region 1421 facing away from the flange 132, which can save manufacturing materials of the protrusion 143, reduce cost, and maintain the overall thickness of the handle body 142 uniform, so as to facilitate integrated processing and forming.

As shown in fig. 12 to 15, in another embodiment of the present invention, the projection 143 includes at least one third sub-projection 1433 extending in the second direction (i.e., the width direction of the shank body 142), the third sub-projection 1433 extending at least from an edge of the first connection region 1421 in the second direction to a portion where the first connection region 1421 is covered by the flange portion 132; correspondingly, the grooves include at least one third sub-groove 1321, each third sub-groove 1321 extends from the outer peripheral wall of the flange 132 to the connection between the flange 132 and the column 131, the third sub-grooves 1321 are in one-to-one correspondence with the third sub-protrusions 1433, and one end of each third sub-protrusion 1433, which is close to the flange 132, is embedded in a corresponding one of the third sub-grooves 1321 (see fig. 15). In this embodiment, by providing the third sub-protrusion 1433 to extend from the edge of the first connection region 1421 in the width direction of the handle body 142 to the portion where the first connection region 1421 is covered by the flange 132, it is ensured that one end of the third sub-protrusion 1433, which is close to the flange 132, can be fitted into a corresponding one of the third sub-grooves 1321 on the flange 132, and it is ensured that the flange 132 covers at least part of the third sub-protrusion 1433, so that the flange 132 can directly press the third sub-protrusion 1433, so that the third sub-protrusion 1433 is fitted into the corresponding third sub-groove 1321, thereby realizing the fixation between the handle body 142 and the flange 132, and also preventing the handle body 142 from warping and improving the sealing performance of the seal ring 17.

It will be appreciated that the more the portion of the third sub-protrusion 1433 near the flange 132 is fitted into the third sub-groove 1321, the better the fixing effect between the stem 142 and the flange 132, the better the warpage preventing effect of the stem 142 and the sealing effect of the sealing ring 17. Preferably, in the example of fig. 12 to 15, the third sub-protrusion 1433 extends from the edge of the first connection region 1421 in the second direction to the third fitting hole 1424, and accordingly, the third sub-groove 1321 extends from the outer circumferential wall of the flange 132 to the region of the flange 132 corresponding to the third fitting hole 1424, so that, in the present embodiment, the third sub-groove 1321 of the flange 132 may receive the end of the third sub-protrusion 1433 near the third fitting hole 1424 to the greatest extent, so that the fixing effect between the handle body 142 and the flange 132 is the best, and the warpage preventing effect on the handle body 142 and the sealing effect on the sealing ring 17 are also the best.

Further, as shown in fig. 12 to 14, in another embodiment of the present invention, the protrusion 143 further includes at least one fourth sub-protrusion 1434 extending along the first direction (i.e., the length direction of the handle body 142), and an orthographic projection of the fourth sub-protrusion 1434 on the first connection region 1421 at least partially coincides with an orthographic projection of the flange portion 132 on the first connection region 1421, that is, the flange portion 132 covers at least part of the fourth sub-protrusion 1434; correspondingly, the groove further includes at least one fourth sub-groove 1322, each fourth sub-groove 1322 extends from the outer peripheral wall of the flange 132 to the connection position of the flange 132 and the column 131, the fourth sub-grooves 1322 are in one-to-one correspondence with the fourth sub-protrusions 1434, and at least one end of each fourth sub-protrusion 1434, which is close to the flange 132, is embedded in a corresponding fourth sub-groove 1322. In this embodiment, by adding the fourth sub-protrusion 1434 extending along the first direction in the area of the first connection region 1421 corresponding to the flange 132, and adding the corresponding fourth sub-groove 1322 to the flange 132, not only the first connection region 1421 and the flange 132 may realize the fitting engagement by the third sub-protrusion 1433 and the corresponding third sub-groove 1321, but also the fitting engagement by the fourth sub-protrusion 1434 and the corresponding fourth sub-groove 1322 may be further realized, so as to facilitate the fixing effect between the first connection region 1421 and the flange 132, thereby further improving the warpage preventing effect of the handle 142 and the sealing effect of the sealing ring 17.

Preferably, similar to the third sub-protrusion 1433, the fourth sub-protrusion 1434 extends to the third assembling hole 1424, that is, the recess formed corresponding to the fourth sub-protrusion 1434 is also communicated with the third assembling hole 1424, so that the flange 132 can accommodate the third sub-protrusion 1433 and the fourth sub-protrusion 1434 to the greatest extent at the same time, which is helpful for further improving the fixing effect between the handle body 142 and the flange 132, the warpage preventing effect on the handle body 142, and the sealing effect of the sealing ring 17.

Alternatively, in an embodiment of the present invention, the number of the third sub-protrusions 1433 and the fourth sub-protrusions 1434 provided on the first connection region 1421 may be one or more, and the flange 132 may be provided with one or more third sub-grooves 1321 corresponding to the third sub-protrusions 1433 and one or more fourth sub-grooves 1322 corresponding to the fourth sub-protrusions 1434, respectively. Preferably, in the embodiment of the present invention, the first connection region 1421 is provided with a plurality of third sub-protrusions 1433 and a plurality of fourth sub-protrusions 1434, the flange portion 132 is correspondingly provided with a plurality of third sub-grooves 1321 and a plurality of fourth sub-grooves 1322, the plurality of third sub-protrusions 1433 are correspondingly matched with the plurality of third sub-grooves 1321 one by one, and the plurality of fourth sub-protrusions 1434 are correspondingly matched with the plurality of fourth sub-grooves 1322 one by one, so as to enhance the fixing effect between the handle body 142 and the flange portion 132, the anti-warping effect on the handle body 142, and the sealing effect of the sealing ring 17. Further preferably, the third sub-protrusions 1433 and the fourth sub-protrusions 1434 are symmetrically disposed about the center of the third fitting hole 1424, which helps to improve uniformity of the fixing effect between the shank body 142 and the flange 132, uniformity of the warpage preventing effect on the shank body 142, and uniformity of the sealing effect of the seal ring 17. In the example of fig. 12 to 14, the number of the third sub-protrusions 1433 and the fourth sub-protrusions 1434 is two, and they are symmetrically disposed about the center of the third assembly hole 1424, and the protrusions 143 provided on the first connection region 1421 are in a cross shape.

In other embodiments, the first connection region 1421 may be configured with two third sub-protrusions 1433 or two fourth sub-protrusions 1434 symmetrically with respect to the center of the third assembly hole 1424, and the flange 132 may be configured with two third sub-grooves 1321 or two fourth sub-grooves 1322, where the two third sub-protrusions 1433 or the two fourth sub-protrusions 1434 are in a shape of a straight line.

In other embodiments, the first connecting region 1421 may further include a plurality of sub-protrusions extending along different radial directions of the third assembling hole 1424, and the flange 132 may correspondingly include a plurality of sub-grooves, which is not limited thereto.

Referring to fig. 14 and 16, in another embodiment of the present invention, since the protrusion 143 on the first connection region 1421 forms a recess on a side of the first connection region 1421 facing the body 121, there is a gap between the pole 13, the body 121 and the first connection region 1421 adjacent to the recess, and there is a possibility that electrolyte may leak from the gap. Preferably, as shown in fig. 16, in one possible embodiment, the sealing ring 17 sleeved on the outer circumferential wall of the cylinder portion 131 may include a sealing ring body 171 and a protrusion 172 connected to the outer wall of the sealing ring body 171, specifically, the sealing ring body 171 is located between the cylinder portion 131 and the cover plate 11, the protrusion 172 extends from a connection with the sealing ring body 171 away from the center of the third fitting hole 1424 in the radial direction of the third fitting hole 1424, and the protrusion 172 is located between the flange portion 132 and the cover plate 11. By arranging the protrusion 172 outside the seal ring body 171 of the seal ring 17, tightness of the area adjacent to the recess between the pole 13, the body 121 and the first connection area 1421 can be improved, so that leakage of electrolyte in the area can be prevented, and in addition, the seal ring 17 provided with the protrusion 172 is helpful to improve anti-rotation effect between the pole 13, the body 121 and the cover plate 11 to a certain extent, so that torsion resistance of the end cover assembly 1 is improved.

In the end cap assembly 1 provided in the above two embodiments, the protrusion 143 and the corresponding groove 123 that can be engaged with each other are disposed between the first connection region 1421 and the body 121, or the protrusion 143 and the corresponding groove that can be engaged with each other are disposed between the first connection region 1421 and the flange 132, so that the first connection region 1421 is prevented from being warped and the sealing performance of the sealing ring 17 is improved. In yet another possible embodiment, the end cap assembly 1 may provide the protrusion 143 and the corresponding groove 123 capable of being engaged and matched between the first connection region 1421 and the body 121, and provide the protrusion 143 and the corresponding groove capable of being engaged and matched between the first connection region 1421 and the flange 132, so that the dual protrusion and the groove are engaged and matched in the end cap assembly 1, which is helpful for further improving the warpage preventing effect on the first connection region 1421 and further improving the sealing performance of the sealing ring 17. Preferably, in order to facilitate the arrangement of the protrusions 143 on opposite sides of the first connection region 1421, the orthographic projection of the groove on the flange 132 on the body 121 and the groove 123 on the body 121 do not overlap each other.

It will be appreciated that, in any embodiment of the present invention, when the depth of the groove corresponding to the protrusion 143 on the first connection region 1421 is too small, the volume of the protrusion 143 embedded in the groove is small, the embedding fit between the protrusion 143 and the groove is unstable, whereas when the depth of the groove is too large, the thickness of the body portion 121 and/or the flange portion 132, which is provided with the groove, is large, which increases the manufacturing cost and the overall thickness of the end cap assembly 1. Preferably, the depth of the groove is 0.3-1mm, and correspondingly, the height of the protrusion 143 is 0.3-1mm. By designing the depth of the groove to be within a reasonable range of 0.3-1mm, problems caused when the depth of the groove is too small or too large can be avoided.

It will be further appreciated that, in the embodiment of the present invention, when the widths of the protrusions 143 and the corresponding grooves are smaller, the processing is inconvenient, and the torque resistance of the protrusions with smaller widths is poor, and the protrusions 143 and the corresponding grooves are easy to deform, whereas when the widths of the protrusions 143 and the corresponding grooves are larger, the widths of the recesses formed on the first connection regions 1421 by the protrusions 143 are also larger, so that the structural strength of the first connection regions 1421 is reduced, and the structural strength of the body portion 121 and/or the flange portion 132 with the grooves with larger widths is also reduced, so that the size of the flange portion 132 is also increased. Preferably, the width of the protrusion 143 and the corresponding groove is 2-5mm, and by designing the widths of the protrusion 143 and the groove to be within a reasonable range of 2-5mm, problems caused by too small or too large widths can be avoided.

The flange 132 of the pole 13 is a generally circular flange. In the embodiment of the present invention, the widths of the protrusion 143 and the groove are denoted as D1, the radii of the flange portion 132 are denoted as D2, and D1 and D2 satisfy the relationship: d2 is less than or equal to 1/3 and D2-D1 is less than or equal to 2/3 and D2. By defining the relationship between D1 and D2 to satisfy this relationship, it is possible to ensure a sufficient fitting area between the projection 143 covered by the flange portion 132 and the corresponding groove thereof, to avoid an excessively small fitting area of the projection 143 and the corresponding groove thereof causing an excessively small acting force to have an insignificant effect on preventing warpage, and to avoid an excessively large fitting area of the projection 143 and the corresponding groove thereof causing an excessively large width of the groove and the projection 143 to have sealability and a press-fit effect of the flange portion 132.

In addition, in the embodiment of the present invention, the end cap assembly 1 further includes other components such as an explosion-proof valve 15, an explosion-proof valve protection sheet 16, a second insulating member 18, and a riveting press block 19, which are provided on the cover plate 11; the end cover assembly 1 can be applied to a cylindrical battery, and the cover plate 11 is a disc-shaped cover plate correspondingly; the end cap assembly 1 may also be applied to a prismatic battery, and the cover plate 11 is a rectangular plate-shaped cover plate.

The structure and function of the end cap assembly 1 according to the embodiments of the present invention will be described in detail below by taking the end cap assembly 1 as an example of application in a cylindrical battery.

Referring to fig. 5, 6 and 11, in one embodiment of the present invention, the cover plate 11 of the disc structure is provided with a first assembly hole 111 in a middle area for penetrating the pole 13, and a pressure release hole 112 penetrating opposite sides of the cover plate 11 in a thickness direction in an area near an edge. The side of the cover plate 11 facing the first insulating member 12 is provided with an explosion-proof valve 15, and the explosion-proof valve 15 covers an orifice of one end of the pressure release hole 112, which is close to the first insulating member 12, so as to be used for performing utility explosion when the battery cell of the end cover assembly 1 is in thermal runaway, thereby avoiding explosion of the battery cell. Preferably, in this embodiment, a first countersink 1121 is formed on a side of the cover plate 11 facing the first insulating member 12 at a position adjacent to the edge of the pressure relief hole 112, the explosion-proof valve 15 is accommodated in the first countersink 1121 and welded to the cover plate 11, and the first insulating member 12 is located on a side of the explosion-proof valve 15 away from the pressure relief hole 112. It should be noted that, the portion of the first insulating member 12 corresponding to the explosion-proof valve 15 is provided with a hollow structure 124, and the hollow structure 124 is used for allowing gas to pass through and gather under the explosion-proof valve 15 when the battery unit body is in thermal runaway, and the explosion-proof valve 15 can be exploded effectively when the pressure of the gathered gas reaches a preset pressure value. In this embodiment, the explosion-proof valve 15 is accommodated and installed in the first sinking groove 1121, so that the overall thickness and volume of the cover plate 11 and the explosion-proof valve 15 can be reduced, and the first insulating member 12 provided with the hollow structure 124 is disposed on a surface of the explosion-proof valve 15 far away from the pressure release hole 112, so that the explosion-proof valve 15 is prevented from being scratched and damaged, and electrolyte is prevented from directly impacting the explosion-proof valve 15, thereby avoiding false triggering of the explosion-proof valve 15. In other embodiments, the explosion-proof valve 15 may be directly welded and fixed to the side of the cover plate 11 facing the first insulating member 12, and the side of the first insulating member 12 facing the cover plate 11 may be provided with a first recess 1121 for accommodating the explosion-proof valve 15, which is not limited thereto.

Further, in the examples of fig. 5, 6 and 11, the side of the cover plate 11 facing away from the first insulating member 12 is provided with an explosion-proof valve protection sheet 16, the explosion-proof valve protection sheet 16 covers an orifice of an end of the pressure relief hole 112 facing away from the first insulating member 12, and the explosion-proof valve protection sheet 16 is used for protecting a side of the explosion-proof valve 15 facing away from the first insulating member 12. Preferably, in the present embodiment, a second countersink 1122 is formed on an edge portion of the cover 11 facing away from the first insulating member 12, which is adjacent to the pressure relief hole 112 and is far away from an opening of the first insulating member 12, and the explosion-proof valve protection sheet 16 is accommodated and mounted in the second countersink 1122. By accommodating and mounting the explosion-proof valve protection sheet 16 in the second sink 1122, the thickness and volume of the end cap assembly 1 are not increased, and the explosion-proof valve protection sheet 16 can also protect a side surface of the explosion-proof valve 15 facing away from the first insulating member 12, so that both opposite side surfaces of the explosion-proof valve 15 are protected, and the safety of the explosion-proof valve 15 is improved. In other embodiments, the explosion-proof valve protection sheet 16 may be directly fixed to the side of the cover plate 11 facing away from the first insulating member 12, which is not limited thereto. It should be noted that, an air vent is left between the edge of the pressure relief hole 112 and the protection sheet 16, and a sufficient gap is left between the protection sheet 16 and the explosion-proof valve 15 to ensure that the explosion-proof valve 15 can be exploded normally. The explosion-proof valve 15 and the explosion-proof valve protecting sheet 16 may be existing explosion-proof valves and protecting sheets, which will not be described in detail.

Referring to fig. 5, 6 and 11 again, in one embodiment of the present invention, the cover 11 is further provided with a first positioning slot 113 and at least one positioning hole 114, the first positioning slot 113 is formed on a side of the cover 11 facing away from the first insulating member 12 and surrounds and communicates with the first assembly hole 111, the positioning hole 114 is formed on a side of the cover 11 facing away from the first insulating member 12, the first positioning slot 113 is used for positioning and installing the second insulating member 18, and the positioning hole 114 is used for positioning and installing the first insulating member 12, and detailed description is omitted herein.

Alternatively, in an embodiment of the present invention, the cover plate 11 may be a conductive metal plate, which may be, but is not limited to, a copper plate, an aluminum plate, a copper alloy plate, or an aluminum alloy plate. In general, when the end cap assembly 1 is used as a positive electrode end cap of a battery cell, the cap plate 11 may be an aluminum plate; when the end cap assembly 1 is used as a negative electrode end cap of the battery cell, the cover plate 11 may be a copper plate.

Referring to fig. 4 to 7, in one embodiment of the present invention, the body 121 is a disc structure with a contour matching the contour of the cover 11. The middle area of the body 121 is provided with a second assembly hole 122 corresponding to the first assembly hole 111 for wearing the pole 13. The hollow structure 124 corresponding to the explosion-proof valve 15 is provided in the area of the body 121 near the edge, and the hollow structure 124 is used for allowing gas to pass through, so as to ensure the explosion-proof valve 15 and normal blasting, where the hollow structure 124 is composed of at least one of a hollow groove and a hollow hole, so long as the gas can be allowed to pass through, and the method is not limited. Further, in this embodiment, at least one positioning post 125 is protruding on a side of the body 121 facing the cover 11, the positioning posts 125 are in one-to-one correspondence with the positioning holes 114 on the cover 11, and the body 121 is mounted on a side of the cover 11 through the cooperation between the positioning posts 125 and the positioning holes 114. In other embodiments, the body 121 may be provided with a positioning hole, and the cover 11 may be provided with a positioning post correspondingly, so that the body 121 may be mounted on one side of the cover 11 through the cooperation of the positioning hole and the positioning post. Of course, in other embodiments, the body 121 may be mounted on one side of the cover 11 by other positioning structures (not limited to the engagement of the clamping groove and the clamping block), which is not limited.

Referring to fig. 3 and fig. 7 together, in one embodiment of the present invention, the first insulating member 12 further includes two rib portions 126 disposed on two opposite sides of the body portion 121 in the radial direction, and the two rib portions 126 are used to enhance the structural strength of the body portion 121. As shown in fig. 3 and 7, a receiving space for setting the first connection area 1421 of the handle body 142 is defined between the pair of rib portions 126 and the body portion 121, the receiving space has a first opening facing away from the body portion 121, and two second openings communicating with the first opening and disposed at opposite intervals in a radial direction of the body portion 121, a spacing direction of the two second openings is perpendicular to a spacing direction of the two rib portions 126, and the hollow structure 124 is disposed in a region of the body portion 121 adjacent to one of the second openings. In the embodiment of the present invention, as shown in fig. 10, when the current collector 14 is in the folded state, at least a partial region (specifically, an opening side region opposite to the first welding groove 1411 and the second welding groove 1412, which will be described later) of the tray portion 141 aligned with the cover plate 11 and the first insulating member 12 is located at a side of the two rib portions 126 away from the body portion 121, so that when the tray portion 141 is subjected to a pressing force (for example, a pressing force of an electrode assembly of a battery cell) toward the body portion 121, the two rib portions 126 may also abut against the tray portion 141, thereby avoiding excessive deformation of the tray portion 141 and contributing to an improvement in structural stability of the end cap assembly 1.

Alternatively, in the example of fig. 3 and 7, each rib portion 126 includes an arc rib protruding from a side of the body portion 121 facing away from the cover plate 11 and extending along a circumferential edge of the body portion 121, a first linear rib located at a side of the arc rib near the second fitting hole 122, and a plurality of second linear ribs connected between the arc rib and the first linear rib, wherein an extending direction of the first linear rib is perpendicular to an extending direction of the second linear rib. In other embodiments, the rib portion 126 may also be formed of a plurality of ribs in other forms, which is not limited thereto.

Referring to fig. 2 to 7, in one embodiment of the present invention, the disc portion 141 is a disc structure with a contour matching the contour of the cover 11, the handle portion 142 is a rectangular sheet structure, and the first connection area 1421 and the second connection area 1422 are located at opposite ends of the handle portion 142 in the length direction. As shown in fig. 4 and 7, the second connection region 1422 is laminated on a side of the disk portion 141 facing the cover plate 11 (i.e., a side facing away from the tab when being welded to the tab), and is welded to the disk portion 141. In other embodiments, the second connecting area 1422 may be directly welded to the outer peripheral wall of the disc portion 141, and the disc portion 141 and the handle portion 142 may be integrally formed. As shown in fig. 3 and 7, the first connection region 1421 is accommodated in the accommodating space between the two rib portions 126 of the first insulating member 12, the first connection region 1421 is provided with a third assembly hole 1424 corresponding to the second assembly hole 122, the column portion 131 of the pole 13 is inserted into the third assembly hole 1424, the second assembly hole 122 and the first assembly hole 111, and the flange portion 132 of the pole 13 is stopped and welded on the side of the first connection region 1421 facing away from the cover plate 11. Preferably, referring to fig. 6 and 8 together, in one embodiment of the present invention, the pole 13 further includes a mounting portion 133, the mounting portion 133 is protruding on a side of the flange 132 facing the column portion 131 and surrounds the column portion 131, and the mounting portion 133 is fittingly inserted into the third mounting hole 1424, which helps to improve the mounting stability of the pole 13.

As shown in fig. 2 and 3, in one embodiment of the present invention, the welding area of the disc portion 141 includes a first welding groove 1411 and a second welding groove 1412 having V shapes, the first welding groove 1411 and the second welding groove 1412 are located at opposite sides of a center line of the handle portion 142 in a width direction, and openings of the first welding groove 1411 and the second welding groove 1412 are opposite to each other. In this embodiment, the first welding groove 1411 and the second welding groove 1412 form grooves on a surface of the plate 141 facing the cover plate 11 (i.e., a side facing away from the tab when welding with the tab), and form protrusions on a surface of the plate 141 facing away from the cover plate 11 (i.e., a side facing the tab) so as to contact with the tab. As shown in fig. 2, a first area (not numbered) is defined between an end of the first welding groove 1411 adjacent to the handle body 142 and an end of the second welding groove 1412 adjacent to the handle body 142 on a side facing the cover plate 11, and the second connection area 1422 is laminated on the first area and welded to the tray body 141. Preferably, as shown in fig. 3, in the protrusions formed on the side of the tray body 141 facing away from the cap plate 11 (i.e., the side facing the tab), the first and second welding grooves 1411 and 1412 are provided with chamfers (beveled or rounded) at corners to prevent the tab from being scratched and damaged when the corners are sharp right angles.

Referring to fig. 2 and 3 again, in one embodiment of the present invention, the disc portion 141 is further provided with a first through hole 1413 and a plurality of second through holes 1414, wherein the first through hole 1413 is disposed between the first welding groove 1411 and the second welding groove 1412 (i.e. the center of the disc portion 141), the plurality of second through holes 1414 is disposed in a second area of the disc portion 141, and the second area is an area between an end of the first welding groove 1411 away from the handle portion 142 and an end of the second welding groove 1412 away from the handle portion 142, and the second area is an area corresponding to the explosion-proof valve 15. The first through hole 1413 and the plurality of second through holes 1414 can each pass gas.

Referring again to fig. 9 to 11, when the current collector 14 is in the folded state, the current collector 14 is folded at the folding region of the handle body 142 as described above. In particular, in the example of fig. 9-11, the inflection zones specifically include a first inflection zone 1425 and a second inflection zone 1426, the first inflection zone 1425 being located in a region of the main body 1423 of the handle body 142 proximate to the second connection zone 1422, the second inflection zone 1426 being located in a region of the main body 1423 proximate to the first connection zone 1421. In the example of fig. 9 to 11, when the current collector 14 is in a folded state, the current collector 14 is folded at the first and second folding regions 1425 and 1426, respectively (see fig. 11), and the cross section in the thickness direction of the current collector 14 is S-shaped. Of course, in other embodiments, the bending region may include only the first bending region 1425 located at the region of the main body 1423 adjacent to the second connection region 1422, and the current collector 14 is bent at the first bending region 1425 when the current collector 14 is in the folded state, and the cross section in the thickness direction of the current collector 14 is U-shaped.

It will be appreciated that, in various embodiments of the present invention, the first connection region 1421 of the handle 142 is fixed to the cover 11, when the current collector 14 is folded only at the first folding region 1425, two opposite side surfaces of the tray 141 may be considered to be folded with respect to the cover 11, and the folded tray 141 needs to face the electrode assembly of the battery cell, so that the raised first welding groove 1411 and the raised second welding groove 1412 contact and are welded with the tab of the electrode assembly, and therefore, when the current collector 14 is in the flattened state, two opposite side surfaces of the tray 141 are not folded with respect to the cover 11, and the raised first welding groove 1411 and the raised second welding groove 1412 should face the cover 11, i.e., face away from the tab. In contrast, in the example of fig. 9 to 11, after the current collector 14 is bent at the first bending region 1425 and the second bending region 1426, the opposite side surfaces of the tray portion 141 may be regarded as not being turned with respect to the cap plate 11, and thus, the first welding groove 1411 and the second welding groove 1412 protruding should face the cap plate 11, i.e., directly face the tab when the current collector 14 is in the flattened state.

Preferably, referring to fig. 3 and 4, in the embodiment of the present invention, a first foolproof structure is disposed in the accommodating space of the first insulating member 12, and a second foolproof structure is disposed in the handle body 142, so that the handle body 142 of the current collector 14 in the flattened state is accommodated and installed in the accommodating space by matching the first foolproof structure and the second foolproof structure, and the orientation of the tray body 141 of the current collector 14 relative to the cover plate 11 is correct. Specifically, in the examples of fig. 3 and fig. 4, the first fool-proof structure is a fool-proof flange 1211 disposed in the accommodating space, the second fool-proof structure is a fool-proof unfilled corner 1429 disposed in the first connection region 1421 of the handle body 142, and the fool-proof unfilled corner 1429 is prevented from abutting against the fool-proof flange 1211, that is, indicates that the orientation of the disc body 141 relative to the cover 11 is correct. Of course, in other embodiments, the first fool-proof structure and the second fool-proof structure may be other types of structural combinations, for example, the cooperation of fool-proof posts and fool-proof holes, so long as the tray body 141 can be ensured to be oriented correctly relative to the cover plate 11, which is not limited.

Further preferably, as shown in fig. 4, in one embodiment of the present invention, the first bending region 1425 and the second bending region 1426 are provided with notches at opposite ends of the width direction of the handle body 142, so as to facilitate bending of the first bending region 1425 and the second bending region 1426.

Alternatively, as shown in fig. 4, in one embodiment of the present invention, the main body 1423 of the handle body 142 may be provided with a reinforcing rib on at least one side in the thickness direction to enhance the structural strength of the main body 1423. Specifically, in the example of fig. 4, a plurality of first reinforcing ribs 1427 are disposed on a side of the main body 1423 facing the cover plate 11 near the first bending region 1425, a plurality of second reinforcing ribs 1428 are disposed on a side of the main body 1423 facing away from the cover plate 11 near the second bending region 1426, and the plurality of first reinforcing ribs 1427 and the plurality of second reinforcing ribs 1428 are disposed along the length direction extending portion distance of the handle body 142 and along the width direction colloid interval of the handle body 142, so that the structural strength of the main body 1423 can be obviously enhanced.

It should be noted that, in the embodiment of the present invention, when the end cap assembly 1 is used as a positive electrode end cap of the battery cell, the current collector 14 may be made of the same aluminum material as the cover plate 11; when the end cap assembly 1 is used as a negative end cap of the battery cell, the current collector 14 may be made of the same copper material as the cap plate 11.

Referring to fig. 2 and fig. 6 to fig. 8, in one embodiment of the present invention, the end cap assembly 1 further includes a second insulating member 18, a riveting press 19, and the sealing ring 17. Wherein, the sealing ring 17 is sleeved on the outer peripheral wall of the column portion 131 of the pole 13, and is used for being pressed and filled between the outer peripheral wall of the column portion 131 and the inner walls of the first assembly hole 111 and the second assembly hole 122, so as to improve the tightness between the pole 13 and the cover plate 11 and the first insulating member 12; the second insulating member 18 and the riveting press block 19 are both provided with a through hole (not numbered in the figure) for allowing one end of the column portion 131 away from the flange portion 132 to pass through, the second insulating member 18 is sleeved on the outer peripheral wall of the column portion 131 to realize insulation between the cover plate 11 and the pole 13, the riveting press block 19 is disposed in a second positioning groove 182 of the second insulating member 18, and the riveting press block 19 is used for welding the end portion of the column portion 131.

Specifically, as shown in fig. 6 to 8, in one embodiment of the present invention, a first positioning block 181 corresponding to the first positioning groove 113 on the cover plate 11 is protruded on a side of the second insulating member 18 facing the cover plate 11, and a circle of flange is protruded on a side of the first positioning block 181 facing the flange portion 132, the second insulating member 18 can be rapidly positioned and mounted on the cover plate 11 by cooperation between the first positioning block 181 and the first positioning groove 113, and the flange is filled between an inner wall of the first assembly hole 111 and an outer wall of the column portion 131, thereby achieving insulation between the cover plate 11 and the post 13. In other embodiments, a first positioning groove may be formed on a side of the second insulating member 18 facing the cover plate 11, and the cover plate 11 is correspondingly provided with a first positioning block, so that the second insulating member 18 may be quickly positioned and installed on the cover plate 11.

Further, as shown in fig. 6 to 8, in one embodiment of the present invention, a second positioning groove 182 is formed on a side of the second insulating member 18 facing away from the cover plate 11, the profile of the riveting pressing block 19 is adapted to the profile of the groove body of the second positioning groove 182, and the riveting pressing block 19 can be quickly positioned and installed in the second positioning groove 182, so as to help reduce the thickness and the volume of the end cover assembly 1. In other embodiments, a second positioning block may be disposed on a side of the second insulating member 18 opposite to the cover plate 11, and the riveting pressing block 19 is correspondingly disposed in a second positioning groove, so that the riveting pressing block 19 may be quickly positioned and installed in the second insulating member 18.

In the embodiment of the present invention, the contour of the first positioning groove 113 and the contour of the first positioning block 181 are adapted, and are not limited to be cross-shaped or in-line-shaped; similarly, the shape of the second positioning groove 182 is adapted to the shape of the riveting pressing block 19, and is not limited to a cross shape or a straight shape. The second insulating member 18 and the first insulating member 12 may be made of plastic, and the first insulating member 12, the second insulating member 18, and the riveting pressing block 19 may be made of plastic under a cover plate, plastic on a cover plate, or a riveting pressing block, which will not be described in detail.

In summary, when the end cap assembly 1 provided in the embodiment of the present invention is applied to a battery cell, the current collector 14 is folded, which can save space and help to increase the energy density of the battery cell. Furthermore, the flange portion 132 and/or the body portion 121 are in fit with the first connection region 1421 through corresponding grooves and protrusions, and the first connection region 1421 is pressed and fixed on the body portion 121 by the flange portion 132, so that the first connection region 1421 can be prevented from being warped, the flange portion 132 is tightly attached to the first connection region 1421, and further, the axis of the column portion 131 is overlapped or approximately overlapped with the axis of the plurality of connecting holes, the column portion 131 can be inserted into the plurality of connecting holes in a position-correcting manner, so that the sealing effect of the sealing ring 17 on the outer wall of the column portion 131 is improved, and leakage of electrolyte from among the pole 13, the first insulating member 12 and the cover plate 11 is avoided; in addition, the first connection area 1421 and the body 121 are in fit with each other through corresponding protrusions and grooves, so that a rotation stopping effect can be achieved, and after the first connection area 1421 is welded to the pole 13, the pole 13 can be prevented from rotating relative to the first insulating member 12 and the cover plate 11 fixed relative to the first insulating member 12, which is helpful for improving the torsion resistance of the end cover assembly 1.

Further, an embodiment of the present invention further provides an energy storage device 100, where the energy storage device 100 includes at least one battery cell. The battery cell comprises a shell, an electrode assembly accommodated in the shell and an end cover assembly packaged at an opening of the shell, wherein the end cover assembly adopts the end cover assembly 1 provided by the embodiment of the invention. The end cover assembly in the battery cell comprises all the technical solutions of all the embodiments, so that the battery cell at least has all the beneficial effects brought by the technical solutions of the embodiments, and the description is omitted herein.

It should be noted that, similar to the existing battery cell, the battery cell further includes other components, for example, an electrolyte contained in the case for infiltrating the electrode assembly, which is not described herein; the electrode assembly may be a conventional wound electrode assembly or a laminated electrode assembly, and is not limited thereto.

Further, the embodiment of the invention further provides electric equipment, which comprises an electric equipment body and the energy storage device 100 provided by the embodiment of the invention, wherein the energy storage device 100 is used for supplying power to the electric equipment body. The energy storage device comprises all the technical solutions of all the embodiments, so that the energy storage device has at least all the beneficial effects brought by the technical solutions of the embodiments, and is not described in detail herein.

The electric equipment can be, but is not limited to, mobile phones, tablet computers, notebook computers, desktop computers, smart bracelets, smart watches, electronic readers, game machines, toys and other electronic equipment, the household energy storage system and the like, and is not limited to the above.

In the description of the present invention, the description with reference to the terms "embodiment," "specific embodiment," "example," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An end cap assembly (1), characterized by comprising:

The cover plate (11) is provided with first assembly holes (111) penetrating through two opposite sides along the thickness direction;

a first insulating member (12) including a body portion (121) provided on one side of the cover plate (11) in the thickness direction, the body portion (121) being provided with second fitting holes (122) penetrating through opposite sides thereof in the thickness direction;

the current collecting piece (14) is arranged on one side, facing away from the cover plate (11), of the body part (121), the current collecting piece (14) comprises a disc body part (141) and a handle body part (142), the disc body part (141) is used for being connected with a tab, the handle body part (142) comprises a first connecting area (1421), a second connecting area (1422) and a main body (1423) connected between the first connecting area (1421) and the second connecting area (1422), the first connecting area (1421) is provided with third assembly holes (1424) penetrating through two opposite sides of the first connecting area (1421) in the thickness direction, the third assembly holes (1424), the second assembly holes (122) and the first assembly holes (111) are correspondingly communicated, and the second connecting area (1422) is connected with the disc body part (141).

A pole (13) comprising a column part (131) and a flange part (132) connected to one end of the column part (131), wherein the column part (131) is penetrated in the communicated third assembly hole (1424), second assembly hole (122) and first assembly hole (111), and the flange part (132) is stopped against one side of the first connection region (1421) facing away from the body part (121);

The body part (121) and/or one side of the flange part (132) facing the first connection area (1421) is provided with a groove, the first connection area (1421) is provided with a bulge (143) corresponding to the groove, and the bulge (143) is embedded in the corresponding groove.

2. The end cap assembly (1) of claim 1, wherein the side of the body portion (121) facing the first connection region (1421) is provided with the recess, the side of the first connection region (1421) facing the body portion (121) is provided with the protrusion (143) corresponding to the recess, and the protrusion (143) forms a recess on the side of the first connection region (1421) facing away from the body portion (121).

3. The end cap assembly (1) of claim 2, wherein one side of the body (1423) along a first direction is connected to the first connection region (1421), the other side of the body (1423) along the first direction is connected to the second connection region (1422), and the first direction is parallel to a plane in which the first connection region (1421) lies;

the projection (143) comprises at least one first sub-projection (1431) extending in a second direction, the first sub-projection (1431) extending at least from an edge of the first connection region (1421) in the second direction to a location where the first connection region (1421) is covered by the flange portion (132), the second direction intersecting the first direction;

The groove comprises at least one first sub-groove (1231), the first sub-grooves (1231) are in one-to-one correspondence with the first sub-protrusions (1431), and each first sub-protrusion (1431) is embedded in a corresponding first sub-groove (1231).

4. The end cap assembly (1) of claim 3, wherein the first sub-projection (1431) extends from an edge of the first connection region (1421) in the second direction to the third fitting hole (1424).

5. The end cap assembly (1) of claim 3, wherein the projection (143) further comprises at least one second sub-projection (1432) extending in the first direction, an orthographic projection of the second sub-projection (1432) onto the first connection region (1421) at least partially coinciding with an orthographic projection of the flange portion (132) onto the first connection region (1421);

the groove further comprises at least one second sub-groove (1232), the second sub-grooves (1232) are in one-to-one correspondence with the second sub-protrusions (1432), and each second sub-protrusion (1432) is embedded in a corresponding second sub-groove (1232).

6. The end cap assembly (1) according to claim 2, wherein the side of the flange portion (132) facing the first connection region (1421) is also provided with the recess, the side of the first connection region (1421) facing the flange portion (132) is provided with a protrusion (143) corresponding to the recess, and the protrusion (143) forms a recess on the side of the first connection region (1421) facing away from the flange portion (132);

Wherein, the orthographic projection of the groove on the flange part (132) on the body part (121) is not overlapped with the groove on the body part (121).

7. The end cap assembly (1) of claim 1, wherein the side of the flange portion (132) facing the first connection region (1421) is provided with the groove, the side of the first connection region (1421) facing the flange portion (132) is provided with the protrusion (143) corresponding to the groove, and the protrusion (143) forms a recess on the side of the first connection region (1421) facing away from the flange portion (132).

8. The end cap assembly (1) of claim 6 or 7, wherein one side of the body (1423) along a first direction is connected to the first connection region (1421), the other side of the body (1423) along the first direction is connected to the second connection region (1422), and the first direction is parallel to a plane in which the first connection region (1421) lies;

the projection (143) comprises at least one third sub-projection (1433) extending in a second direction, the third sub-projection (1433) extending at least from an edge of the first connection region (1421) in the second direction to a location where the first connection region (1421) is covered by the flange portion (132), the second direction intersecting the first direction;

The grooves comprise at least one third sub-groove (1321), each third sub-groove (1321) extends from the outer circumferential wall of the flange part (132) to the joint of the flange part (132) and the column part (131), the third sub-grooves (1321) are in one-to-one correspondence with the third sub-protrusions (1433), and one end, close to the flange part (132), of each third sub-protrusion (1433) is embedded in the corresponding one third sub-groove (1321).

9. The end cap assembly (1) of claim 8, wherein the third sub-projection (1433) extends from an edge of the first connection region (1421) in the second direction to the third fitting hole (1424).

10. The end cap assembly (1) of claim 8, wherein the projection (143) further comprises at least one fourth sub-projection (1434) extending in the first direction, an orthographic projection of the fourth sub-projection (1434) onto the first connection region (1421) at least partially coinciding with an orthographic projection of the flange portion (132) onto the first connection region (1421);

the groove further comprises at least one fourth sub-groove (1322), each fourth sub-groove (1322) extends from the outer peripheral wall of the flange part (132) to the joint of the flange part (132) and the column part (131), the fourth sub-grooves (1322) and the fourth sub-protrusions (1434) are in one-to-one correspondence, and at least one end, close to the flange part (132), of each fourth sub-protrusion (1434) is embedded in the corresponding one fourth sub-groove (1322).

11. The end cap assembly (1) according to claim 6 or 7, wherein the end cap assembly (1) further comprises a sealing ring (17), the sealing ring (17) is sleeved on the outer peripheral wall of the cylinder portion (131), the sealing ring (17) comprises a sealing ring body (171) and a protruding portion (172) connected to the outer wall of the sealing ring body (171), the sealing ring body (171) is located between the cylinder portion and the cover plate (11), the protruding portion (172) extends from a connection portion with the sealing ring body (171) along the radial direction of the third assembly hole (1424) away from the center of the third assembly hole (1424), and the protruding portion (172) is located between the flange portion (132) and the cover plate (11).

12. The end cap assembly (1) of claim 1, wherein the first connection region (1421) is provided with a plurality of sub-protrusions, and the plurality of sub-protrusions are symmetrically arranged about a center of the third assembly hole (1424);

and/or the depth of the groove is 0.3-1mm, and the height of the protrusion (143) is 0.3-1mm;

and/or, the width of the protrusion (143) and the groove is D1, the radius of the flange portion (132) is D2, and D1 and D2 satisfy the relation: d2 is less than or equal to 1/3 and D2-D1 is less than or equal to 2/3 and D2.

13. An energy storage device (100) comprising an end cap assembly (1) according to claims 1 to 12.

14. A powered device comprising an energy storage device (100) as claimed in claim 13.