WO2024169154A1 - Top cover assembly and secondary battery - Google Patents

Abstract

The present application relates to the technical field of energy storage devices, and relates to a top cover assembly and a secondary battery. The top cover assembly comprises: a top cover sheet, the top cover sheet being provided with pole through holes; pole terminals, each pole terminal comprising an insertion section and an exposed section, wherein the insertion section is provided with transition slots, the insertion section penetrates into the corresponding pole through hole, the exposed section is located on the periphery of the insertion section, and the exposed section is connected to the surface of the top cover sheet adjacent to the corresponding pole through hole; and sealing members, each sealing member being accommodated in the corresponding transition slot, and the sealing member being connected to the slot wall of the corresponding transition slot. In this way, the structure of the top cover assembly can be simplified, the requirement for light weight of a secondary battery is effectively satisfied, and the risk of accumulation of liquid in the pole terminals in the top cover assembly can be reduced.

Description

Top cover assembly and secondary battery

This application claims the priority of the Chinese patent application filed with the China Patent Office on February 17, 2023, with application number 202320328956.9 and application name “Top cover assembly and secondary battery”, all contents of which are incorporated by reference in this application.

Technical Field

The present application belongs to the field of energy storage technology, and specifically relates to a top cover assembly and a secondary battery.

Background Art

Today, the new energy vehicle industry is booming, and battery lightweighting will receive more and more attention. The battery adopts a riveted block design, and the riveted block and the base plate are set on the pole for assembly, which leads to problems such as difficulty in improving battery space utilization and difficulty in battery lightweight design.

Technical Solutions

The present application provides a top cover assembly, comprising:

A top cover sheet, wherein the top cover sheet is provided with a pole through hole;

The pole terminal comprises an insertion section and an exposed section, the insertion section is provided with a transition groove, the insertion section is inserted into the pole through hole, the exposed section is located at the periphery of the insertion section, and the exposed section is connected to the surface of the top cover sheet adjacent to the pole through hole;

A sealing member is accommodated in the transition groove and is connected to a groove wall of the transition groove.

In some embodiments, the exposed segment has a first end surface and a second end surface opposite to each other along the axial direction of the pole through hole, and the second end surface is pressed against a surface of the top cover sheet adjacent to the pole through hole.

In some embodiments, a cap is also included, the cap includes a cover portion and a protrusion arranged on the side of the cover portion facing the top cover sheet, the cover portion covers the first end surface, and the protrusion is inserted into the transition groove.

In some embodiments, the protrusion is engaged with the transition groove, a sealing member is provided between the protrusion and the transition groove, and the protrusion contacts the sealing member inside the transition groove.

In some embodiments, the pole terminal further includes a base body, which is disposed at one end of the insertion section away from the exposed section. The exposed section, the insertion section and the base body are combined to form a groove, and the groove clamps the top cover sheet.

In some embodiments, the exposed segment, the inserted segment and the base are an integrally formed structure.

In some embodiments, it also includes an upper plastic, which includes a main body and a matching part. The main body is arranged around the matching part. The main body and the matching part are arranged on one side of the top cover sheet close to the exposed section. The matching part is clamped axially between the top cover sheet and the exposed section.

In some embodiments, the top cover sheet is further provided with a receiving groove, which is arranged around the pole through hole; the main body portion and the matching portion are both assembled in the receiving groove.

In some embodiments, the mating portion includes a concave-convex structure, and the concave-convex structure abuts against the second end surface.

In some embodiments, it also includes a lower plastic sheet, which is arranged on the side of the top cover sheet away from the exposed section, and the lower plastic sheet is provided with an assembly hole, and the insertion section is inserted into the assembly hole and the pole through hole; two protrusions are provided on the side of the lower plastic sheet away from the top cover sheet, and the two protrusions are enclosed to form a limiting groove, and the limiting groove is connected and aligned with the assembly hole along the axial direction, and the base is assembled in the limiting groove and supports the lower plastic sheet.

In some embodiments, the protrusions extend along the circumference of the base to enclose and form limiting grooves.

In some embodiments, the bump is a complete annular structure extending along the circumference of the base.

In some embodiments, there are multiple protrusions, and the multiple protrusions are distributed in sequence along the circumference of the substrate.

In some embodiments, a sealing ring is also included, which includes a first sealing portion and a second sealing portion, the second sealing portion is arranged around the first sealing portion, the first sealing portion extends axially to the pole through hole, and the first sealing portion is clamped between the insertion section and the top cover sheet, and the second sealing portion extends radially along the pole through hole, and the second sealing portion is clamped between the base and the top cover sheet.

The present application also provides a secondary battery, comprising: a shell, a battery cell and a top cover assembly as described above, wherein the battery cell is arranged in the shell, and the top cover assembly is arranged on the shell.

In some embodiments, the secondary battery also includes an explosion-proof valve assembly, which is installed on the top cover sheet of the top cover assembly. The explosion-proof valve assembly includes a protective film, an explosion-proof valve and a mounting hole. The mounting hole is opened on the top cover sheet, the explosion-proof valve is installed between the top cover sheet and the lower plastic, the explosion-proof valve is passed through the mounting hole, and the protective film is bonded to the top cover sheet to cover the mounting hole.

BRIEF DESCRIPTION OF THE DRAWINGS

The technical solution and other beneficial effects of the present application will be made apparent by describing in detail the specific implementation methods of the present application in conjunction with the accompanying drawings.

FIG1 is a schematic diagram of the appearance of a top cover assembly provided in an embodiment of the present application;

FIG2 is an exploded schematic diagram of the top cover assembly of FIG1 ;

Fig. 3 is a longitudinal sectional view of Fig. 1;

FIG4 is a partial enlarged schematic diagram of point A in FIG3 ;

FIG5 is a schematic structural diagram of a pole terminal of a top cover assembly;

FIG6 is a schematic diagram of the matching between the pole terminal and the cap of the top cover assembly;

FIG7 is a partial enlarged schematic diagram of a portion C in FIG6;

Figure markings, 100-top cover sheet, 101-pole through hole, 200-pole terminal, 210-insertion section, 220-exposed section, 221-first end face, 222-second end face, 230-transition groove, 300-seal, 400-cap, 410-protrusion, 500-upper plastic, 510-main body, 520-matching part, 120-accommodating groove, 240-base, 250-groove, 600-sealing ring, 610-first sealing part, 620-second sealing part, 700-lower plastic sheet, 710-assembly hole, 720-protrusion, 730-limiting groove, 800-explosion-proof valve assembly, 810-protective film, 820-explosion-proof valve, 830-mounting hole.

Embodiments of the present application

The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances. In the description of the present application, "plurality" means two or more, unless otherwise clearly and specifically limited. In addition, The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more features.

The disclosure below provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application.

Please refer to Figures 1 to 7. The present application provides a top cover assembly. The top cover assembly includes a top cover sheet 100, a pole terminal 200, and a seal 300. The top cover sheet 100 is provided with a pole through hole 101. The pole terminal 200 includes an insertion section 210 and an exposed section 220, the insertion section 210 is provided with a transition groove 230, the insertion section 210 is penetrated in the pole through hole 101, the exposed section 220 is located at the periphery of the insertion section 210, and the exposed section 220 is connected to the surface of the top cover sheet 100 adjacent to the pole through hole 101.

The top cover assembly of the present application forms a transition groove 230 on the pole terminal 200, and rolls the skirt of the transition groove 230 outward to form an exposed section 220, so that the exposed section 220 extends radially along the pole through hole 101 and overlaps on the top cover sheet 100. The insertion section 210 and the exposed section 220 of the present application cooperate to form a self-riveting structure, which can replace the riveting block to play the riveting role, so that the riveting block can be omitted, and the structure of the top cover assembly can be simplified, so that the cost and weight of the top cover assembly are significantly reduced, and the space utilization rate is greatly improved, so that the demand for lightweight secondary batteries can be effectively met. In addition, in this embodiment, the pole terminal 200 also includes a transition groove 230 provided in the insertion section 210, and the transition groove 230 can reduce the weight of the pole terminal 200, and further meet the demand for lightweight secondary batteries.

It is understandable that the design of the exposed section 220 extending radially along the pole through hole 101 and overlapping the top cover sheet 100 can realize the assembly of the pole terminal 200 and the top cover sheet 100, and the pole terminal 200 and the top cover sheet 100 are insulated.

Furthermore, the seal 300 is accommodated in the transition groove 230, and the seal 300 is connected to the groove wall of the transition groove 230, so that the seal 300 seals the internal space of the transition groove 230. As shown in FIG4 , the seal 300 is arranged in the transition groove 230, and the seal 300 is used to seal the internal space of the transition groove 230, which can reduce the risk of liquid accumulation in the transition groove 230, and thus can reduce the risk of liquid accumulation in the pole terminal 200 in the top cover assembly.

In one embodiment, as shown in Fig. 4 and Fig. 5, the exposed section 220 has a first end face 221 and a second end face 222 which are opposite to each other along the axial direction Z of the pole through hole 101, the second end face 222 is pressed against the surface of the top cover sheet 100 adjacent to the pole through hole 101, and the second end face 222 is insulated and connected to the top cover sheet 100 adjacent to the pole through hole 101, so as to realize the assembly of the pole terminal 200 and the top cover sheet 100. The shape of the pole through hole 101 can be circular, elliptical, etc.

In one embodiment, as shown in FIG. 7 , the top cover assembly further includes a cap 400, which includes a cover portion and a protrusion 410 disposed on the side of the cover portion facing the top cover sheet 100, and the protrusion 410 is disposed around the surface of the cap 400 facing the top cover sheet 100. The first end surface 221 is opposite to the cap 400, the cover portion covers the first end surface 221, and the protrusion 410 is inserted into the transition groove 230. The cap 400 is disposed on the first end surface 221, and the cap 400 produces axial Z extrusion on the pole terminal 200, so as to cause the exposed section 220 of the pole terminal 200 to extend and deform in the radial direction to form a flange structure.

Furthermore, the protrusion 410 is snap-fitted with the transition groove 230, and a seal 300 is provided between the protrusion 410 and the transition groove 230. The protrusion 410 contacts the seal 300 inside the transition groove 230 to eliminate the matching gap between the pole terminal 200 and the protrusion 410 of the cap 400. The seal 300 is a rubber seal ring. The seal 300, i.e., the rubber seal ring, can eliminate the matching gap between the transition groove 230 and the protrusion 410. By inserting the protrusion 410 into the transition groove 230, the snap-fitting between the protrusion 410 and the transition groove 230 is achieved, and the protrusion 410 is connected to the pole terminal. 200 The crimping fixation at the top.

In one embodiment, as shown in FIG. 4 and FIG. 5 , the pole terminal 200 further includes a base 240, which is disposed at one end of the insertion section 210 away from the exposed section 220, and the base 240 protrudes from the insertion section 210 along the radial direction of the pole through hole 101, and the radial dimension of the base 240 along the pole through hole 101 is greater than the radial dimension of the exposed section 220 along the pole through hole 101; the exposed section 220, the insertion section 210 and the base 240 enclose a groove 250, and the groove 250 clamps the top cover sheet 100. The exposed section 220, the insertion section 210 and the base 240 are an integrally formed structure.

In one embodiment, as shown in FIG. 4 and FIG. 7 , the top cover assembly further includes an upper plastic 500, the upper plastic 500 includes a main body 510 and a matching part 520, the main body 510 is arranged around the matching part 520, the main body 510 and the matching part 520 are arranged on one side of the top cover sheet 100 close to the exposed section 220, the matching part 520 is clamped between the top cover sheet 100 and the exposed section 220 along the axial direction Z, and the edge of the exposed section 220 abuts against the main body 510; the cover part of the cap 400 covers the first end face 221 and is crimped onto the main body 510 of the upper plastic 500; the main body 510 and the matching part 520 are an integrally formed structure. By sandwiching the upper plastic 500 between the exposed section 220 and the top cover sheet 100, insulation between the exposed section 220 and the top cover sheet 100 is achieved, the supporting and buffering effect on the pole through hole 101 is increased, and the connection strength between the various parts is ensured.

Furthermore, in some embodiments, the mating portion 520 includes a concave-convex structure, which abuts against the second end face 222. The concave-convex structure is designed to increase the friction between the second end face 222 and the mating portion 520, thereby increasing the fixed assembly effect between the second end face 222 and the mating portion 520, and the exposed section 220 is not easy to slip on the mating portion 520 along the radial direction of the pole through hole 101.

In one embodiment, as shown in FIG. 4 , the top cover sheet 100 is further provided with a receiving groove 120, which is arranged around the pole through hole 101, and the side of the top cover sheet 100 facing the cap 400 is provided with the receiving groove 120; the upper plastic 500 is assembled in the receiving groove 120, and specifically, the body portion 510 and the matching portion 520 are both assembled in the receiving groove 120. The receiving groove 120 is used to accommodate the upper plastic 500, so that the upper plastic 500 is directly arranged on the side of the top cover sheet 100 facing the cap 400, so that the height of the upper plastic 500 along the axial direction Z of the pole through hole 101 is relatively small, and the height of the exposed section 220 from the axial direction Z of the pole through hole 101 to the top cover sheet 100 after overlapping the upper plastic 500 is relatively small, so that the overall height of the pole terminal 200 is small.

In one embodiment, as shown in Figures 4 and 7, the top cover assembly also includes a lower plastic sheet 700, which is arranged on the side of the top cover sheet 100 away from the exposed section 220, and an assembly hole 710 is arranged on the side of the lower plastic sheet 700 facing the exposed section 220, and a protrusion 720 is arranged on the side of the lower plastic sheet 700 away from the top cover sheet 100, and the protrusion 720 is surrounded to form a limiting groove 730, and the limiting groove 730 is connected and aligned with the assembly hole 710 along the axial direction Z, the insertion section 210 is penetrated through the pole through hole 101 and the assembly hole 710, the base 240 is assembled in the limiting groove 730 and the base 240 resists the lower plastic sheet 700.

Furthermore, the protrusion 720 extends along the circumference of the base 240 to enclose a limiting groove 730. The protrusion 720 can specifically be a complete annular structure extending along the circumference of the base 240; or there can be multiple protrusions 720, and the multiple protrusions 720 are distributed in sequence along the circumference of the base 240, which is not limited here.

In one embodiment, as shown in FIG. 4 , the top cover assembly further includes a sealing ring 600, the sealing ring 600 includes a first sealing portion 610 and a second sealing portion 620, the second sealing portion 620 is arranged around the first sealing portion 610, the first sealing portion 610 extends in the axial direction Z in the pole through hole 101, the first sealing portion 610 is clamped between the insertion section 210 and the top cover sheet 100, the second sealing portion 620 extends in the radial direction of the pole through hole 101, the second sealing portion 620 is clamped between the base 240 and the top cover sheet 100, and the first sealing portion 610 and the second sealing portion 620 are an integrally formed structure. By configuring the first sealing portion 610 between the insertion section 210 and the top cover sheet 100, configuring the second sealing portion 620 between the base 240 and the top cover sheet 100, The second sealing portion 620 is received in the assembly hole 710, so as to realize the insulation between the insertion section 210 and the top cover sheet 100 between the pole through hole 101 and the insertion section 210 and the top cover sheet 100 in the assembly hole 710, and realize the base 240 to abut against the lower plastic sheet 700 in the limiting groove 730. The sealing ring 600 can be made of materials such as PFA, PPS or fluororubber.

The present application also provides a secondary battery, comprising: a shell, a battery cell and a top cover assembly as described above, wherein the battery cell is arranged in the shell, the top cover assembly is arranged on the shell, the top cover assembly comprises a pole terminal 200, and the pole terminal 200 is connected to the battery cell. The secondary battery also comprises an explosion-proof valve assembly 800, the explosion-proof valve assembly 800 is mounted on the top cover sheet 100, the explosion-proof valve assembly 800 comprises a protective film 810, an explosion-proof valve 820 and a mounting hole 830, the mounting hole 830 is opened on the top cover sheet 100, the explosion-proof valve 820 is mounted between the top cover sheet 100 and the lower plastic 700, the explosion-proof valve 820 is penetrated in the mounting hole 830, the protective film 810 is bonded to the top cover sheet 100 to cover the mounting hole 830, the mounting hole 830 is used to prevent the battery from exploding, the shape of the mounting hole 830 can be square, oval, runway, etc., and the shape of the protective film 810 can be square, oval, runway, etc.

The secondary battery can meet the problem of solving the demand for lightweight batteries. The top cover assembly includes: a top cover sheet 100, the top cover sheet 100 is provided with a pole through hole 101; a pole terminal 200, the pole terminal 200 includes an insertion section 210 and an exposed section 220, the insertion section 210 is provided with a transition groove 230, the insertion section 210 is penetrated in the pole through hole 101, the exposed section 220 is located at the periphery of the insertion section 210, and the exposed section 220 is connected to the surface of the top cover sheet 100 adjacent to the pole through hole 101; a seal 300, the seal 300 is accommodated in the transition groove 230, and the seal 300 is connected to the groove wall of the transition groove 230. The pole terminal 200 is penetrated in the pole through hole 101 through the insertion section 210, and the exposed section 220 extends radially along the pole through hole 101 and overlaps on the top cover sheet 100. The insertion section 210 and the exposed section 220 of the present application cooperate to form a self-riveting structure, which can replace the rivet block to perform the riveting function, thereby eliminating the rivet block, simplifying the structure of the top cover assembly, significantly reducing the cost and weight of the top cover assembly, and greatly improving the space utilization, thereby effectively meeting the demand for lightweight secondary batteries.

In addition, the insertion section 210 of the present application is provided with a transition groove 230, and a seal 300 is configured in the transition groove 230. The seal 300 is used to seal the internal space of the transition groove 230, which can reduce the risk of liquid accumulation in the transition groove 230, thereby reducing the risk of liquid accumulation in the pole terminal 200 in the top cover assembly.

In summary, the present application provides a top cover assembly and a secondary battery. The top cover assembly includes a top cover sheet and a pole terminal. The pole terminal includes an insertion section and an exposed section, the insertion section is inserted into the pole through hole of the top cover sheet, the exposed section is located at the periphery of the insertion section, and the exposed section is connected to the surface of the top cover sheet adjacent to the pole through hole. In other words, the pole terminal of the top cover assembly of the present application is inserted into the pole through hole through its insertion section, and the exposed section abuts against the top cover sheet, that is, the pole terminal of the present application forms a self-riveting structure, eliminating the riveting block in the prior art, and can simplify the structure of the top cover assembly, thereby effectively meeting the demand for lightweight secondary batteries. The pole terminal of the present application also includes a transition groove provided in the insertion section, and the transition groove can reduce the weight of the pole terminal, further meeting the demand for lightweight secondary batteries.

In addition, the top cover assembly also includes a seal, which is accommodated in the transition groove and connected to the groove wall of the transition groove, so that the seal seals the internal space of the transition groove, which can reduce the risk of liquid accumulation in the transition groove, and thus can reduce the risk of liquid accumulation in the pole terminal in the top cover assembly.

The top cover assembly and the secondary battery provided in the embodiments of the present application are described in detail above. The principles and implementation methods of the present application are described in detail using specific examples. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or Some of the technical features are replaced by equivalents; however, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims (16)

A top cover assembly, comprising: A top cover sheet, wherein the top cover sheet is provided with a pole through hole; A pole terminal, the pole terminal comprising an insertion section and an exposed section, the insertion section being provided with a transition groove, the insertion section being inserted into the pole through hole, the exposed section being located at the periphery of the insertion section, and the exposed section being connected to a surface of the top cover sheet adjacent to the pole through hole; A sealing member is accommodated in the transition groove and connected to a groove wall of the transition groove. The top cover assembly according to claim 1, wherein the exposed section has a first end face and a second end face opposite to each other along the axial direction of the pole through hole, and the second end face is pressed against a surface of the top cover sheet adjacent to the pole through hole. The top cover assembly according to claim 2, further comprising a cap, the cap comprising a cover portion and a protrusion arranged on the side of the cover portion facing the top cover sheet, the cover portion covers the first end surface, and the protrusion is inserted into the transition groove. The top cover assembly according to claim 3, wherein the protrusion is snap-fitted with the transition groove, a sealing member is provided between the protrusion and the transition groove, and the protrusion contacts the sealing member inside the transition groove. The top cover assembly according to claim 2, wherein the pole terminal further comprises a substrate, the substrate is arranged at one end of the insertion section away from the exposed section, the exposed section, the insertion section and the substrate are combined to form a groove, and the groove clamps the top cover sheet. The top cover assembly according to claim 5, wherein the exposed section, the inserted section and the base are an integrally formed structure. The top cover assembly according to claim 2, further comprising an upper plastic, wherein the upper plastic comprises a main body portion and a matching portion, the main body portion is arranged around the matching portion, the main body portion and the matching portion are arranged on a side of the top cover sheet close to the exposed section, and the matching portion is clamped between the top cover sheet and the exposed section along the axial direction. According to the top cover assembly of claim 7, wherein the top cover sheet is further provided with a receiving groove, and the receiving groove is arranged around the pole through hole; the main body part and the matching part are both assembled in the receiving groove. The top cover assembly according to claim 7, wherein the matching portion includes a concave-convex structure, and the concave-convex structure abuts against the second end surface. The top cover assembly according to claim 5, further comprising a lower plastic sheet, wherein the lower plastic sheet is arranged on a side of the top cover sheet away from the exposed section, the lower plastic sheet is provided with an assembly hole, the insertion section is penetrated through the assembly hole and the pole through hole; the lower plastic sheet is provided with a protrusion on the side away from the top cover sheet, the protrusions enclose to form a limiting groove, the limiting groove is connected and aligned with the assembly hole along the axial direction, the base is assembled in the limiting groove and abuts against the lower plastic sheet. The top cover assembly according to claim 10, wherein the protrusion extends along the circumference of the base to enclose and form the limiting groove. The top cover assembly according to claim 11, wherein: The projection is a complete annular structure extending along the circumference of the base. The top cover assembly according to claim 11, wherein: There are multiple protrusions, and the multiple protrusions are distributed in sequence and at intervals along the circumference of the base. The top cover assembly according to claim 5, further comprising a sealing ring, the sealing ring comprising a first sealing portion and a second sealing portion, the second sealing portion being arranged around the first sealing portion, the first sealing portion extending in the axial direction to the pole through hole, and the first sealing portion being clamped between the insertion section and the top cover sheet, the second sealing portion extending in the radial direction of the pole through hole, and the second sealing portion being clamped between the base and the top cover sheet. A secondary battery comprises: a shell, a battery cell and a top cover assembly as claimed in any one of claims 1 to 14, wherein the battery cell is arranged in the shell, and the top cover assembly is arranged on the shell. The secondary battery according to claim 15, wherein the secondary battery further comprises an explosion-proof valve assembly, the explosion-proof valve assembly is mounted on the top cover sheet of the top cover assembly, the explosion-proof valve assembly comprises a protective film, an explosion-proof valve and a mounting hole, the mounting hole is opened on the top cover sheet, the explosion-proof valve is mounted between the top cover sheet and the lower plastic, the explosion-proof valve is penetrated into the mounting hole, and the protective film is bonded to the top cover sheet to cover the mounting hole.