CN217158358U - Top cover assembly and single battery - Google Patents

Abstract

The application discloses a top cover assembly and a single battery, wherein the top cover assembly comprises a cover plate and a connecting terminal, and the cover plate is provided with a first through hole; connecting terminal includes utmost point post, insulating part and connecting piece, and the insulating part has the second through-hole, and the insulating part is at least partly pegged graft in first through-hole, and utmost point post is at least partly pegged graft in the second through-hole, and utmost point post and connecting piece pass through the insulating part and are connected structure as an organic whole to make connecting terminal wholly connect in the apron through the connecting piece. In the top cap subassembly of this application embodiment, utmost point post is at least partly pegged graft in the second through-hole, the at least part of at least grafting of insulating part is in first through-hole, top cap subassembly's height will show the limit and be less than utmost point post like this, the high sum of insulating part and connecting piece, can reduce connecting terminal's overall height, and then make the battery cell content can hold more bulky electric core, help improving battery cell's energy density, and top cap subassembly's connecting terminal is integrated as an organic whole, be convenient for assemble.

Description

Top cover assembly and single battery

Technical Field

The application relates to the technical field of energy storage devices, in particular to a top cover assembly and a single battery.

Background

At present, with the development of electric vehicles, consumers have higher and higher requirements for the endurance of the electric vehicles, and as an energy storage device for providing electric energy for the electric vehicles, the energy density of a power battery is a direct influence factor of the endurance mileage, however, common ways for improving the energy density of the power battery, such as improving the specific capacities of positive and negative electrode active materials, have fallen into bottlenecks along with the development of technologies, and restrict the improvement of the endurance of the electric vehicles.

SUMMERY OF THE UTILITY MODEL

The present application is directed to solving at least one of the problems in the prior art. To this end, the present application provides a cap assembly capable of reducing the total height and improving the energy density of a battery.

The application also discloses the battery cell who uses above-mentioned top cap subassembly.

A cap assembly according to a first embodiment of the present application, comprising:

a cover plate having a first through hole;

the connecting terminal comprises a pole, an insulating part and a connecting part, wherein the insulating part is provided with a second through hole, at least part of the insulating part is inserted into the first through hole, at least part of the pole is inserted into the second through hole, and the pole and the connecting part are connected into an integral structure through the insulating part, so that the connecting terminal is integrally connected to the cover plate through the connecting part.

According to the top cap subassembly of this application embodiment, have following beneficial effect at least:

the pole is at least partially inserted into the second through hole, so that the pole can be installed by utilizing the internal space of the insulating part, and the pole and the insulating part are at least partially overlapped in the height direction; similarly, the insulating member is at least partially inserted into the first through hole, and the insulating member may be installed using the inner space of the cover plate such that the insulating member and the cover plate at least partially overlap in the height direction. Based on above-mentioned structure, the height of top cap subassembly will show the height sum that the limit is less than utmost point post, insulating part, connecting piece and apron, can reduce connecting terminal's overall height, and then makes the battery cell content can hold more bulky electric core, helps improving battery cell's energy density. On the other hand, the pole and the connecting piece are connected into a whole through the insulating piece, so that the connecting terminal can participate in the assembly of the top cover assembly as a whole, and the assembly steps can be reduced.

In other embodiments of this application, the material of insulating part is the plastic, utmost point post with the connecting piece passes through insulating part injection moulding's mode is connected structure as an organic whole.

In other embodiments of this application, connecting terminal is still including being located sealing washer in the second through-hole follows the inboard direction to the outside of apron, the terminal surface of sealing washer with the terminal surface laminating of utmost point post, just the outer peripheral face of sealing washer with the inner peripheral surface laminating of second through-hole, utmost point post the connecting piece with the sealing washer passes through the insulating part is connected as an organic whole structure.

In other embodiments of the present application, the insulating member is made of a ceramic material, and the post and the connecting member are connected to form an integral structure by means of ceramic sintering.

In other embodiments of the present application, the connecting member includes a first connecting portion located radially outside the insulating member and connected to the cap plate.

In other embodiments of the present application, the end surface of the cover plate has a mounting groove, the mounting groove is disposed around the first through hole, and the first connecting portion is at least partially located in the mounting groove.

In other embodiments of the present application, the connecting member includes a second connecting portion, at least a portion of the second connecting portion is located inside the insulating member, the second connecting portion has a limiting hole, the insulating member includes a limiting portion, and the limiting portion is inserted into the limiting hole to limit displacement between the insulating member and the connecting member.

In other embodiments of the present application, the connecting member includes a third connecting portion, the third connecting portion is located on a radially inner side of the insulating member, an inner side to an outer side direction of the cover plate, and the third connecting portion supports the pole.

In other embodiments of the present application, one of the inner circumferential surface of the insulating member and the outer circumferential surface of the pole column is provided with a fourth connecting portion, the other of the inner circumferential surface of the insulating member and the outer circumferential surface of the pole column is provided with a slot, and the fourth connecting portion is located in the slot to limit displacement between the insulating member and the pole column in the axial direction.

In other embodiments of this application, the apron still includes explosion-proof valve mounting hole, the top cap subassembly still includes explosion-proof valve, explosion-proof valve includes installation department, first rib and deformation portion, first rib encircle in the deformation portion sets up, the installation department encircle in first rib sets up, and with the border of explosion-proof valve mounting hole is connected.

In other embodiments of this application, the apron still includes annotates the liquid hole, the top cap subassembly still includes sealed nail, sealed nail connect in the apron is in order to seal annotate the liquid hole, wherein, sealed nail's outer end face has the recess.

In other embodiments of the present application, the seal nail further includes a second reinforcement portion disposed at the bottom wall of the groove.

A unit cell according to a second embodiment of the present application includes:

a battery case;

the top cover assembly is connected to the battery shell and defines a mounting cavity with the battery shell;

the battery cell is positioned in the installation cavity and comprises a battery cell main body and a lug, and the lug is respectively electrically connected with the pole column and the battery cell main body.

In other embodiments of the present application, the single battery further includes a tab limiting member, and the tab limiting member is located between the battery cell main body and the top cap assembly and has a tab channel;

the lug is arranged in the lug channel in a penetrating mode and can be limited by the lug limiting part.

In other embodiments of the present application, the tab channel includes a first cavity and a second cavity, the tab includes a folding portion and an extending portion, the folding portion is located in the first cavity and electrically connected to the battery cell main body, and the extending portion penetrates through the second cavity and is electrically connected to the terminal.

In other embodiments of the present application, the battery cell further includes a battery cell protection film, the battery cell protection film has a first positioning structure, the cap assembly has a second positioning structure, and the battery cell protection film is coated on the outer side of the battery cell main body and is positioned by the first positioning structure and the second positioning structure.

Additional aspects and advantages of the present application 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 present application.

Drawings

The present application is further described with reference to the following figures and examples, in which:

FIG. 1 is a perspective view of a cap assembly according to an embodiment of the present application;

FIG. 2 is an exploded view of the cap assembly of FIG. 1;

FIG. 3 is a sectional view of the connection terminal of FIG. 1 connected to a cover plate;

FIG. 4 is an exploded view of a cap assembly according to another embodiment of the present application;

FIG. 5 is a sectional view of the connection terminal and the cap plate of FIG. 4;

FIG. 6 is a schematic perspective view of an explosion-proof valve according to an embodiment of the present application;

FIG. 7 is a cross-sectional view of the explosion-proof valve of FIG. 6;

FIG. 8 is a cross-sectional view of the seal pin and cover plate connection according to an embodiment of the present application;

FIG. 9 is a cross-sectional view of the seal nail of FIG. 8;

FIG. 10 is a cross-sectional view of another embodiment of a seal pin;

fig. 11 is a cross-sectional view of a tab limiting member in an embodiment of the present application;

fig. 12 is a cross-sectional view of the tab limiting member and the cell of fig. 11;

fig. 13 is an exploded schematic view of a cell protection film and a cell in an embodiment of the present application.

Reference numerals:

the explosion-proof valve comprises a top cover assembly 100, a cover plate 110, a first through hole 111, a mounting groove 112, an explosion-proof valve mounting hole 113, a liquid injection hole 114, a connecting terminal 120, a pole 121, an insulating member 122, a second through hole 1221, a limiting part 1222, a fourth connecting part 1223, a connecting member 123, a first connecting part 1231, a second connecting part 1232, a limiting hole 1233, a third connecting part 1234, a sealing ring 124, an explosion-proof valve 130, a mounting part 131, a first reinforcing part 132, a bending part 1321, a deformation part 133, a sealing nail 140, a groove 141, a second reinforcing part 142, a side surface 143, a plastic part 150 and a projection 151;

the battery cell comprises a battery cell 200, a battery cell main body 210, a tab 220, a folding part 221 and a protruding part 222;

the tab limiting piece 300, the tab channel 310, the first cavity 311 and the second cavity 312;

cell protection film 400, breach 410.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it is to be understood that the positional descriptions, such as the directions of up, down, front, rear, left, right, etc., referred to herein are based on the directions or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the present application.

In the description of the present application, the meaning of a plurality is one or more, the meaning of a plurality is two or more, and the above, below, exceeding, etc. are understood as excluding the present number, and the above, below, within, etc. are understood as including the present number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present application, unless otherwise expressly limited, terms such as set, mounted, connected and the like should be construed broadly, and those skilled in the art can reasonably determine the specific meaning of the terms in the present application by combining the detailed contents of the technical solutions.

In the description of the present application, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," 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 application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Under the certain circumstances of total height of battery cell, if the size of top cap subassembly along the direction of height is bigger, then the inside space that is used for placing electric core of battery cell can be littleer, is unfavorable for improving battery cell's energy density like this. Based on the above problem, this application embodiment provides a top cap subassembly, and it can reduce the size of direction of height to place bigger volume's electric core in the inside of battery cell, in addition, the connecting terminal of top cap subassembly is integrated as an organic whole, is convenient for assemble.

The cap assembly 100 includes a cap plate 110 and a connection terminal 120, the cap plate 110 is used for sealing the battery case of the single battery, and the connection terminal 120 is used for electrically connecting the internal battery cell and the external electrical device, which will be described in detail below with reference to the drawings.

Referring to fig. 1, the cap plate 110 has a plate-shaped structure, is made of a metal material such as aluminum, and has both conductivity and strength to mount the connection terminal 120. Referring to fig. 2, the cover plate 110 is provided with a first through hole 111 for mounting the connection terminal 120, and the first through hole 111 may be a circular hole as illustrated.

The overall height of the cap assembly 100 is mainly determined by the height of the connection terminal 120, and thus controlling the height of the connection terminal 120 helps to control the overall height of the cap assembly 100. Referring to fig. 2, the connection terminal 120 includes a terminal post 121, an insulating member 122, and a connection member 123, where one end of the terminal post 121 is electrically connected to a tab of the battery cell, and the other end is used to be electrically connected to an external device. The pole 121 is a copper-aluminum composite cylinder, in some embodiments, the upper portion is an aluminum plate, the lower portion is a copper plate, and the height of the pole 121 can be reduced by adopting plate composite. The insulating member 122 is used to realize isolation between the pole post 121 and the cover plate 110, and simultaneously, can realize connection between the pole post 121 and the connecting member 123. The insulating member 122 is made of an insulating material, and in some embodiments, the insulating member 122 may be made of ceramic, plastic, etc., and different materials may have different connection modes, which will be described in detail below. The connecting member 123 is used to fix the connecting terminal 120 and the cover plate 110, and the connecting member 123 is usually made of a metal material, and is conveniently connected with the cover plate 110 by welding, and generally, the connecting member and the cover plate can be connected by laser welding.

Referring to fig. 2 and 3, the insulating member 122 is an annular member, and has a second through hole 1221 inside, and the pole 121 is at least partially inserted into the second through hole 1221, so that the pole 121 can be installed in the internal space of the insulating member 122, and the pole 121 and the insulating member 122 at least partially overlap in the height direction; similarly, the insulating member 122 is at least partially inserted into the first through hole 111, and the insulating member 122 may be installed using the inner space of the cap plate 110 such that the insulating member 122 and the cap plate 110 at least partially overlap in the height direction. Based on the above structure, the height of the cap assembly 100 is significantly limited to be less than the sum of the heights of the terminal 121, the insulating member 122 and the connecting member 123, so that the total height of the connecting terminal 120 can be reduced, and thus the battery cell can accommodate a larger-sized battery cell.

Wherein, the terminal surface of utmost point post 121 can be with insulating part 122 correspond the terminal surface parallel and level, be less than insulating part 122 correspond the terminal surface or be a little higher than insulating part 122 correspond the terminal surface, to two kinds of back situations, the difference in height between utmost point post 121 and the insulating part 122 should be controlled within the settlement scope, for example, utmost point post 121 is higher than insulating part 122 highly within 1mm to 3mm, avoids the difference in height too big and increase connecting terminal 120's total height. Similarly, the closer the end surface of the insulating member 122 is to the corresponding end surface of the cap plate 110, the more advantageous it is to control the overall height of the connection terminal 120. It can be understood that when the height of the insulating member 122 and the cover plate 110 is not greater than the height of the pole 121, the total height of the connection terminal 120 is the smallest, i.e., equal to the height of the pole 121.

It should be noted that the top cover assembly 100 generally further includes other auxiliary structures, such as a plastic member 150 shown in fig. 2, 3, 4 and 5, and the plastic member 150 is substantially a plate-shaped structure and is connected to the lower side of the cover plate 110.

On the other hand, the pole 121 and the connecting member 123 are connected to form an integral structure through the insulating member 122, that is, the pole 121, the connecting member 123 and the insulating member 122 are pre-molded to form an integral structure, so that the connecting terminal 120 can participate in the assembly of the top cover assembly 100 as a whole, and the assembly steps can be reduced.

In some embodiments, the insulating member 122 is made of plastic, that is, the terminal post 121 and the connecting member 123 are connected to form an integral structure by injection molding, which is easy to process and relatively low in cost. Referring to fig. 3, the pole 121 is directly attached to the hole wall of the second through hole 1221 of the insulating member 122, and only by the connection force generated during plastic curing, and limited by this connection manner, a contact portion between the pole 121 and the insulating member 122 may have a small air hole, which may cause gas leakage. The connection terminal 120 of this embodiment further includes a sealing ring 124, the sealing ring 124 is located in the second through hole 1221, and along a direction from an inner side (a side facing the inside of the battery) to an outer side (a side facing the outside of the battery) of the cover plate 110, that is, along a direction from bottom to top in fig. 3, an upper end surface of the sealing ring 124 is attached to a lower end surface of the pole 121 to seal between the sealing ring 124 and the pole 121, and in addition, an outer peripheral surface of the sealing ring 124 is attached to an inner peripheral surface of the second through hole 1221 to seal between the sealing ring 124 and the insulating member 122, so that leakage between the pole 121 and the insulating member 122 can be effectively reduced.

The sealing ring 124 can be connected with the pole 121 and the connecting member 123 through the insulating member 122 to form an integral structure, so that the connecting terminal 120 can be integrally assembled without adding an additional assembling step.

In some embodiments, referring to fig. 4 and 5, the insulating member 122 is made of a ceramic material, that is, the terminal post 121 and the connecting member 123 are connected into a whole by ceramic sintering, and since the micro pores between the insulating member 122 and the terminal post 121 formed by sintering are small, gas is difficult to leak from the contact portion, the sealing ring 124 can be omitted in this embodiment, so that the number of components can be reduced, and the structure of the connection terminal 120 can be simplified. In addition, reducing the sealing ring 124 also helps to reduce the overall height of the connection terminal 120.

In some embodiments, referring to fig. 2 and 3, the connecting element 123 has a first connecting portion 1231 connected to the cover plate 110, and in some embodiments, the first connecting portion 1231 extends from the outer side of the insulating element 122 and extends along the radial direction of the pole 121, so that the highest position of the first connecting portion 1231 is not higher than the highest position of the connecting terminal 120, and the lowest position of the first connecting portion 1231 is not lower than the lowest position of the connecting terminal 120, so that the first connecting portion 1231 does not increase the height dimension of the connecting terminal 120. The first connection portion 1231 may be a sheet-like structure, specifically, an annular sheet surrounding the insulating member 122 by one turn, and the annular first connection portion 1231 is welded to the cover plate 110, so that the contact area between the first connection portion 1231 and the cover plate 110 may be increased, and the first connection portion 1231 and the cover plate 110 can be in sealing contact to avoid leakage.

Based on the above embodiment, the end surface of the cover plate 110 may further be provided with the mounting groove 112, the mounting groove 112 is disposed around the first through hole 111, and the first connection portion 1231 is at least partially located in the mounting groove 112, so that the first connection portion 1231 can be completely hidden inside the cover plate 110, or at least the height of the first connection portion 1231 protruding from the cover plate 110 can be reduced. In the example shown in fig. 3, the mounting groove 112 is located at the lower end surface of the cover plate 110, and a portion of the first connection portion 1231 is located within the mounting groove 112. In the example shown in fig. 5, the mounting groove 112 is located at the upper end surface of the cover plate 110, and the first connection portion 1231 is completely located at the mounting groove 112.

In some embodiments, the connecting member 123 further includes a second connecting portion 1232, and at least a portion of the second connecting portion 1232 is located inside the insulating member 122, so as to achieve a fixed connection between the insulating member 122 and the connecting member 123. Taking fig. 2 and 3 as an example, the second connecting portion 1232 is a ring-shaped sidewall, and is entirely covered in the insulating member 122. Based on the above structure, the first connection portion 1231 is connected to the second connection portion 1232, specifically, one end of the first connection portion 1231 is connected to the second connection portion 1232 and is wrapped in the insulating member 122, and the other end of the first connection portion extends out of the insulating member 122 along the radial direction of the pole 121, and the extending portion is welded to the cover plate 110.

When the insulating member 122 is a plastic member formed outside the second connecting portion 1232 by an injection molding process, the connection strength between the insulating member 122 and the second connecting portion 1232 is relatively low, and in order to improve the problem, the second connecting portion 1232 is further provided with the limiting hole 1233, for example, when the second connecting portion 1232 is placed along the axial direction of the pole 121 as shown in fig. 3, the limiting hole 1233 penetrates through the second connecting portion 1232 along the radial direction of the pole 121, so that after the connecting member 123 is placed in a mold, the molten glue is filled in the limiting hole 1233, after the glue is solidified, the limiting portion 1222 is formed in the limiting hole 1233, and the limiting portion 1222 is integrally connected with other portions of the insulating member 122, so that the second connecting portion 1232 can neither move along the axial direction of the pole 121 relative to the insulating member 122 nor rotate around the axis of the pole 121, thereby increasing the connection strength between the connecting member 123 and the insulating member 122. It should be noted that the second connecting portion 1232 may be provided with a plurality of limiting holes 1233, and the plurality of limiting holes 1233 are distributed along the circumferential direction of the second connecting portion 1232, so as to form a plurality of limiting portions 1222 to further increase the connecting strength.

In some embodiments, referring to fig. 2 and 3, the connecting member 123 further includes a third connecting portion 1234, where the third connecting portion 1234 is connected to the second connecting portion 1232 and located on a radially inner side of the insulating member 122, so as to support the pole 121 in a direction from an inner side to an outer side of the cover plate 110 (e.g., a direction from bottom to top in the drawing), it should be noted that the third connecting portion 1234 is located on the radially inner side of the insulating member 122 only to limit a position relationship of the two in the radial direction, and the third connecting portion 1234 has multiple arrangements in the axial direction, for example, the third connecting portion 1234 is located below the insulating member 122 in the axial direction of the pole 121 in fig. 3, and in other embodiments, the third connecting portion 1234 may protrude from an inner sidewall of the insulating member 122 so as to be located in the second through hole 1221.

The third connecting portion 1234 may be a ring-shaped bottom plate as shown in the drawings, and the second connecting portion 1232 is connected to the third connecting portion 1234, specifically, the outer side edge of the third connecting portion 1234, and extends along the axial direction of the pole 121. When the injection molding scheme is adopted and the pole 121, the insulating member 122, the connecting member 123 and the sealing ring 124 need to be integrated, the sealing ring 124 and the pole 121 can be sequentially placed on the third connecting portion 1234 according to the sequence from bottom to top, then the positioned pole 121, the connecting member 123 and the sealing ring 124 are placed into a mold for injection molding, and after injection molding, the whole connecting terminal 120 can be formed together with the insulating member 122. When the above sintering molding scheme is adopted and the pole 121, the insulating member 122 and the connecting member 123 need to be integrated, the pole 121 can be placed on the third connecting portion 1234 first, then the positioned pole 121 and the positioned connecting member 123 are placed into a mold for injection molding, and after injection molding, the whole connecting terminal 120 can be formed together with the insulating member 122.

When the connecting member 123 includes the first connecting portion 1231, the second connecting portion 1232, and the third connecting portion 1234, the first connecting portion 1231 and the third connecting portion 1234 are respectively located at two opposite sides of the second connecting portion 1232 along the radial direction of the pole 121, and the first connecting portion 1231 and the third connecting portion 1234 may be flush with each other or may be staggered from each other along the axial direction of the pole 121.

In some embodiments, referring to fig. 5, one of the inner circumferential surface of the insulating member 122 and the outer circumferential surface of the pole post 121 is provided with a fourth connecting portion 1223, the other of the inner circumferential surface of the insulating member 122 and the outer circumferential surface of the pole post 121 is provided with a slot, and the fourth connecting portion 1223 is located in the slot and can limit the relative movement between the pole post 121 and the insulating member 122 in the axial direction. Taking the example shown in the figure, the outer circumferential surface of the pole 121 is provided with a slot, in the process of preparing the connection terminal 120, the slot is filled with ceramic powder, the ceramic powder in the slot forms a fourth connection portion 1223 after sintering, and the fourth connection portion 1223 is integrally connected with other portions of the insulator 122, so that the axial movement between the insulator 122 and the pole 121 can be limited.

Of course, the fourth connection portion 1223 may be provided on the outer peripheral surface of the pole 121, and the sintered fourth connection portion 1223 may be coated inside the insulating member 122, thereby achieving the effect of limiting.

Referring to fig. 2 and 4, the cover plate 110 further includes an explosion-proof valve mounting hole 113, and the cap assembly 100 further includes an explosion-proof valve 130, wherein the explosion-proof valve 130 is mounted on the cover plate 110 to close the explosion-proof valve mounting hole 113, and when the internal pressure rises to a set range due to a failure inside the battery, the explosion-proof valve 130 will burst to release pressure, thereby reducing the risk of explosion of the battery. The explosion-proof valve 130 is generally fixedly connected with the edge of the explosion-proof valve mounting hole 113 in a welding mode, when the pressure in the battery gradually rises, the explosion-proof valve 130 protrudes outwards firstly and drives the edge to protrude outwards synchronously, so that the stress mode of the explosion-proof valve 130 can be changed, and the potential safety hazard that the explosion-proof valve 130 is difficult to explode when reaching the detonation range exists. Based on this, referring to fig. 6 and 7, the present embodiment provides an improved explosion-proof valve structure, which includes a mounting portion 131, a first reinforcing portion 132, and a deformation portion 133, where the first reinforcing portion 132 is disposed around the deformation portion 133, the mounting portion 131 is disposed around the first reinforcing portion 132, the deformation portion 133 is configured to burst after pressure is applied, the mounting portion 131 is configured to be connected to an edge of the explosion-proof valve mounting hole 113, and the first reinforcing portion 132 can increase a local strength of the explosion-proof valve 130, and reduce a deformation amount transmitted from the deformation portion 133 to the cover plate 110, so that the explosion-proof valve 130 can burst normally after a preset pressure is applied.

Referring to fig. 7, the first reinforcing part 132 may include a ring-shaped bent part 1321, and the bent part 1321 may be formed by, for example, stamping, in which case the wall thickness of the first reinforcing part 132 is substantially uniform. In some embodiments, the first reinforcing part 132 includes a plurality of bent parts 1321 along a radial direction of the pole 121, and the plurality of bent parts 1321 form a wave structure.

As an alternative to the above, the first reinforcing part 132 may also include more than one protrusion, i.e., the wall thickness of the first reinforcing part 132 at the protrusion is greater than the wall thickness at other positions.

Furthermore, the wall thickness of the mounting portion 131 may be greater than the wall thickness of the deformation portion 133, so that the mounting portion 131 has a greater resistance to deformation.

Referring to fig. 8 and 9, the cover plate 110 is further provided with a filling hole 114, and an external electrolyte can be filled into the battery through the filling hole 114, and after the filling is completed, the filling hole 114 is closed by a sealing nail 140. Generally, the sealing nail 140 is welded to the cover plate 110 by means of circumferential welding, and the internal stress of the welding may cause the sealing nail 140 to tilt. To improve the above problem, the outer end face of the sealing nail 140 in some embodiments is further provided with a groove 141, so that the sealing nail 140 is provided as a thin shell structure. When the sealing nail 140 is installed, the sealing nail 140 is welded to the inner circumferential surface of the liquid injection hole 114 through the side surface 143, and even if local internal stress is concentrated, the sealing nail 140 can absorb the internal stress through certain deformation, so that the warping of the sealing nail 140 is reduced. The sealing nail 140 may be formed with the groove 141 by a punching process.

Referring to fig. 10, the sealing nail 140 further includes a second reinforcement portion 142, and the second reinforcement portion 142 is disposed on the bottom wall of the groove 141, and can enhance the deformation resistance of the bottom wall, so that the deformation is concentrated on the circumferential side wall of the sealing nail 140. The second reinforcing portion 142 may be an annular bent portion or a protrusion, and it should be noted that the bent portion may be formed by stamping, so that the whole sealing nail 140 may be manufactured by stamping, which is convenient for processing.

The embodiment of the present application further provides a single battery, which includes a battery case (not shown), a top cover assembly 100 and a battery core 200, where the top cover assembly 100 is connected to an opening of the battery case by welding or the like, so as to define a mounting cavity together with the battery case, and the battery core 200 is located in the mounting cavity.

The battery cell 200 mainly includes a cell main body 210 and a tab 220, wherein one end of the tab 220 is electrically connected to the cell main body 210, and the other end is electrically connected to the terminal 121. In order to realize the positioning and insulation of the tab 220, adhesive tapes are usually applied to two sides of the tab 220, however, when the adhesive tapes are in an electrolyte environment for a long time, the adhesive tapes are easy to fall off due to loss of viscosity, so that the tab 220 is in a free state, and thus, the condition that a separator is inserted into the tab 220 in the production and use processes of the battery is easy to occur, thereby causing a series of problems such as ignition and explosion of the battery. Based on the above problem, the single battery of this embodiment further includes a tab limiting member 300, and the tab limiting member 300 can limit the tab 220, and will not fail due to the electrolyte environment.

With particular reference to fig. 11 and 12, the tab limiting member 300 is disposed between the cell main body 210 and the top cap assembly 100, and may be made of a hard material capable of withstanding an electrolyte environment. The inside of utmost point ear locating part 300 is provided with utmost point ear passageway 310, and the one end of utmost point ear passageway 310 extends to the up end of electric core main part 210, and the other end extends to utmost point post 121, and the major structure of utmost point ear 220 is located utmost point ear passageway 310, and the upper end stretches out in order to connect utmost point post 121 from utmost point ear passageway 310. The width of the tab passage 310 is slightly greater than that of the corresponding tab 220, so that the tab 220 can pass through the tab passage, and the displacement of the tab 220 can be limited, thereby preventing the tab from being inserted into the separator.

In general, in order to reduce the space occupied by the tab 220, a section of the tab 220 close to the cell main body 210 is folded, wherein a folded portion of the tab 220 is described as a folded portion 221, an unfolded portion is described as an extending portion 222, the folded portion 221 is located on the upper end surface of the cell main body 210, one end of the folded portion is connected to the cell main body 210, the other end of the folded portion is connected to the extending portion 222, and the other end of the extending portion 222 is connected to the terminal 121. To accommodate such a tab 220, in some embodiments, the tab passage 310 includes a first cavity 311 and a second cavity 312, the first cavity 311 is close to the cell main body 210, and the second cavity 312 is close to the pole 121 and is disposed substantially in a vertical direction. The width of the first cavity 311 is greater than that of the second cavity 312 along the width direction (i.e., the left-right direction in fig. 12) of the cell main body 210. During installation, the folded portion 221 of the tab is received in the first cavity 311, the protruding portion 222 is inserted into the second cavity 312, and the top end of the protruding portion extends out of the second cavity 312 and is electrically connected to the pole 121.

In some embodiments, the width of the folding portion 221 is gradually reduced along a direction away from the upper end surface of the cell main body 210 (i.e., a direction from bottom to top in fig. 12), so that the width of the first cavity 311 is also adaptively reduced to ensure a limiting effect on the folding portion 221. The width of the second cavity 312 remains constant, which is suitable for limiting the unfolded tab 220.

In some embodiments, the overall width of the tab limiting member 300 is gradually reduced along the direction from bottom to top, so as to adapt to the shape of the internal tab passage 310, avoid excessive wall thickness differences of each portion of the tab limiting member 300, be inconvenient for molding by injection molding and the like, and reduce the volume of the tab limiting member 300. The lower end surface of the tab limiting member 300 may be a plane, which is parallel to the upper end surface of the battery cell main body 210, and the width of the tab limiting member 300 is equal to or slightly smaller than the width of the upper end surface, so that the tab limiting member 300 can be stably placed above the battery cell main body 210.

The single battery is usually further provided with a battery cell protective film to perform insulation protection on the battery cell, and in an actual production process, the battery cell protective film is easily subjected to position deviation and exceeds the cover plate 110, so that quality problems are caused in a subsequent welding process. In order to improve the above problem, the cell protection film in some embodiments can be positioned by a positioning structure, specifically, the cell protection film 400 has a first positioning structure, a component, such as the plastic part 150, in the cap assembly 100 has a second positioning structure, and the cell protection film 400 is positioned by the first positioning structure and the second positioning structure, so as to prevent the cell protection film 400 from being displaced. Wherein, the positioning of the first positioning structure and the second positioning structure to the battery cell protective film 400 includes: the circumferential positioning of the cell protection film 400 and the top cap assembly 100, the axial positioning of the cell protection film 400 and the top cap assembly 100 along the pole 121, and the combination of the two positioning.

In some embodiments, one of the first positioning structure and the second positioning structure is a convex structure, and the other is a concave structure, and the convex structure is positioned by being embedded into the concave structure. Taking fig. 13 as an example, the first positioning structure is a notch 410 disposed on the upper edge of the cell protection film 400, the second positioning structure is a protrusion 151 disposed on the side surface of the plastic part 150, during assembly, the cell protection film 400 is sleeved on the outer side of the cell main body 210, and the cell protection film 400 and the plastic part 150 are positioned by the protrusion 151 and the notch 410, at this time, the position between the cell protection film 400 and the cover plate 110 is determined, and the cell protection film 400 cannot move along the circumferential direction of the cover plate 110, or move along the axial direction of the pole 121, so as to prevent the cell protection film 400 from exceeding the cover plate 110. After the battery cell protection film 400 is positioned, the upper end of the battery cell protection film 400 is welded to the cover plate 110 through laser welding and other modes, so that the battery cell protection film 400 can be fixed, and the problem of welding quality caused by position deviation between the battery cell protection film 400 and the cover plate 110 can be effectively solved through the above modes.

Referring to fig. 13, each side of the cell protective film 400 may have a first positioning structure, and each side of the plastic part 150 may have a second positioning structure, so as to enhance the positioning effect.

It should be noted that the cell protection film 400 is a thin film structure, the wall thickness is generally uniform, and the plastic part 150 is an injection molding structure, and the shape thereof can be flexibly adjusted according to the design, so that the notch 410 and the protrusion 151 are respectively formed on the cell protection film 400 and the plastic part 150, which is more convenient for processing.

The application also provides a battery pack, including the box and the battery cell of above-mentioned each embodiment, battery cell is located the inside of box, and it should be explained that the box both can be the box structure of integral type, also can be the split type box structure that the mounting structure concatenation such as by the curb plate formed.

The embodiments of the present application have been described in detail with reference to the drawings, but the present application is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present application. Furthermore, the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

Claims (10)

1. A header assembly, comprising:

a cover plate having a first through hole;

the connecting terminal comprises a pole, an insulating part and a connecting part, wherein the insulating part is provided with a second through hole, at least part of the insulating part is inserted into the first through hole, at least part of the pole is inserted into the second through hole, and the pole and the connecting part are connected into an integral structure through the insulating part, so that the connecting terminal is integrally connected to the cover plate through the connecting part.

2. The top cap assembly of claim 1, wherein the insulating member is made of plastic, and the post and the connecting member are connected to form an integral structure by injection molding of the insulating member.

3. The top cap assembly of claim 2, wherein the connection terminal further comprises a sealing ring disposed in the second through hole, an end surface of the sealing ring is attached to an end surface of the pole along a direction from the inner side to the outer side of the cover plate, an outer circumferential surface of the sealing ring is attached to an inner circumferential surface of the second through hole, and the pole, the connection member and the sealing ring are connected to form an integral structure through the insulating member.

4. The cap assembly of claim 1, wherein the insulating member is made of a ceramic material, and the post and the connecting member are connected to form an integral structure by sintering the insulating member.

5. The header assembly of any one of claims 1-4, wherein the connector comprises a first connector portion located radially outward of the insulator and connected to the cover plate.

6. The header assembly of claim 5, wherein the cover plate has a mounting slot on an end surface thereof, the mounting slot being disposed around the first through hole, the first connection portion being at least partially disposed within the mounting slot.

7. The header assembly of any one of claims 1-4, wherein the connector comprises a second connector portion, at least a portion of the second connector portion being located within the insulator, the second connector portion having a retention aperture, the insulator comprising a retention portion that is inserted into the retention aperture to limit displacement between the insulator and the connector.

8. The header assembly of any one of claims 1-4, wherein the connector includes a third connecting portion located radially inward of the insulator, the third connecting portion supporting the post in a medial to lateral direction of the cover plate.

9. The header assembly of any one of claims 1 to 4, wherein one of the inner circumferential surface of the insulator and the outer circumferential surface of the pole post is provided with a fourth connecting portion, and the other of the inner circumferential surface of the insulator and the outer circumferential surface of the pole post is provided with a slot, the fourth connecting portion being located within the slot to limit axial displacement between the insulator and the pole post.

10. A battery cell, comprising:

a battery case;

the cap assembly of any one of claims 1 to 9, coupled to the battery housing and defining a mounting cavity with the battery housing;

the battery cell is positioned in the installation cavity and comprises a battery cell main body and a lug, and the lug is respectively electrically connected with the pole column and the battery cell main body.

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