CN217606919U

CN217606919U - Button cell and shell thereof

Info

Publication number: CN217606919U
Application number: CN202221146615.1U
Authority: CN
Inventors: 曹琳; 王传宝
Original assignee: Dongguan Liwinon Energy Technology Co ltd
Current assignee: Dongguan Liwinon Energy Technology Co ltd
Priority date: 2022-05-13
Filing date: 2022-05-13
Publication date: 2022-10-18
Anticipated expiration: 2032-05-13

Abstract

The utility model relates to a button cell and shell thereof, the shell includes: the shell comprises a first structural member with an opening at one end and a second structural member with an opening at one end, the first structural member is sleeved in the second structural member, the opening direction of the first structural member is consistent with that of the second structural member, and the first structural member or the second structural member is provided with a clearance hole; the cover body covers the opening and is fixedly connected with the first structural component or the second structural component to form a sealed cavity; the insulating part is arranged between the first structural part and the second structural part and used for insulating the first structural part and the second structural part, and through holes are formed in the positions, corresponding to the clearance holes, of the insulating part. Through the compound effective area who increases first structure, insulating part and second structure, increase joint strength makes encapsulation reliability promote, and the weeping risk of battery is controlled simultaneously, has solved button cell because of the damaged weeping of battery and the condition of short circuit appear in the sealing washer extrusion excessively.

Description

Button cell and shell thereof

Technical Field

The utility model belongs to the technical field of lithium ion battery makes, concretely relates to button cell and shell thereof.

Background

Nowadays, with the rapid growth of population and the rapid development of social economy, the shortage of resources and energy sources is increasing, the environmental protection is increasingly emphasized, and the development and saving of energy sources become an important subject in the world today. Energy is the basis for the existence and development of human society, and the modern society based on fossil energy is increasingly frequently suffering from energy shortage and environmental pollution crisis. Meanwhile, with the coming of the information-oriented high-tech era, the energy application form is changing, and the demand of renewable, pollution-free, small-sized and discrete mobile high-performance power sources is rapidly increasing. Green, high-efficiency secondary batteries are being vigorously developed in various countries. The lithium ion battery as a novel secondary battery has the advantages of high energy density and power density, high working voltage, light weight, small volume, long cycle life, good safety, environmental protection and the like, and is widely applied to the field of intelligent wearing.

The common steel shell button battery is of a three-piece structure and comprises two semi-surrounding shells and a sealing ring arranged between the two shells, wherein the two metal shells are the positive and negative electrodes of the battery respectively, and the sealing ring is used for sealing and insulating. Because the two shells are mechanically sealed through the sealing ring, the sealing ring needs to be thickened in consideration of the compression ratio of the sealing ring, the space utilization rate of the battery is reduced because the sealing ring does not participate in the electrochemical reaction of the battery, and short circuit or liquid leakage of the battery is easily caused due to uneven stress of a sealing area.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: the button cell and the shell thereof are provided aiming at the defects of the prior art, and the problems of damage, leakage and short circuit of the cell caused by excessive extrusion of the sealing ring are solved.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

in a first aspect, the utility model provides a button cell's shell, include:

the shell comprises a first structural member with an opening at one end and a second structural member with an opening at one end, the first structural member is sleeved in the second structural member, the opening direction of the first structural member is consistent with that of the second structural member, and the first structural member or the second structural member is provided with a clearance hole;

the cover body covers the opening and is fixedly connected with the first structural member or the second structural member to form a sealed cavity;

the insulating part is arranged between the first structural part and the second structural part and used for insulating the first structural part and the second structural part, and through holes are formed in the positions, corresponding to the clearance holes, of the insulating part.

Preferably, the first structural member includes a first bottom wall and a first side wall fixedly connected to the first bottom wall, the second structural member includes a second bottom wall fixedly connected to a second side wall of the second bottom wall, and the first bottom wall or the second bottom wall is provided with a clearance hole.

Preferably, the clearance hole is formed in the first bottom wall, the first side wall protrudes out of the opening of the second structural member, and the cover body covers the opening of the first structural member and is fixedly connected with the first side wall.

Preferably, the second bottom wall is provided with the clearance hole, the second side wall protrudes out of the opening of the first structural member, and the cover body covers the opening of the second structural member and is fixedly connected with the second side wall.

Preferably, the first bottom wall is provided with a convex part at a position corresponding to the clearance hole, and the convex part penetrates out of the clearance hole.

Preferably, the convex part and the first bottom wall are integrally formed, and the convex part is of a hollow structure.

Preferably, the first side wall or the second side wall is provided with a positioning groove, and the cover body is assembled in the positioning groove.

Preferably, the cover body is provided with explosion-proof grains.

Preferably, the thickness of the insulating part is 0.030-0.1mm.

In a second aspect, the present invention provides a button cell, which includes an electrical core and a housing according to the first aspect, wherein the electrical core is accommodated in the housing.

The utility model discloses following beneficial effect has at least:

one end of the battery is provided with the first structural member with an opening, the first structural member is sleeved in the second structural member with an opening, the opening direction of the first structural member is consistent with the opening direction of the second structural member, the first structural member and the second structural member are fixedly connected together through the insulating part, meanwhile, the fixed connection area of the first structural member and the second structural member is increased due to the fact that the first structural member is sleeved in the second structural member, and therefore the composite effective area of the first structural member, the second structural member and the insulating part is increased, packaging reliability is greatly improved, the leakage risk of the battery is controlled, meanwhile, due to the fact that the composite effective area is increased, the connection strength between the first structural member and the second structural member is increased. In addition, the insulating part of this application sets up between first structure and second structure, bond first structure and second structure, and need not extrude the insulating part through first structure and second structure and make the insulating part take place deformation and reach sealed effect, consequently, the insulating part is compared in prior art mechanical seal's sealing washer, can be under the less condition of thickness, guarantee the sealing reliability of first structure and second structure, and can not appear leading to the battery to appear short circuit or weeping because of sealing regional atress inequality.

The first structural member or the second structural member is provided with a clearance hole, and the insulating member is provided with a through hole at a position corresponding to the clearance hole. The clearance hole and the through hole are arranged so that the battery cell can be electrically connected with an external circuit through the shell.

Drawings

Features, advantages and technical effects of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of a button cell according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a battery cell according to an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a housing according to an embodiment of the present invention.

Fig. 4 is a second schematic structural diagram of the housing according to the embodiment of the present invention.

Fig. 5 is a third schematic structural diagram of the housing according to the embodiment of the present invention.

Fig. 6 is a fourth schematic structural view of the housing according to the embodiment of the present invention.

Fig. 7 is a fifth schematic structural view of the housing according to the embodiment of the present invention.

Fig. 8 is a sixth schematic structural view of the housing according to the embodiment of the present invention.

Fig. 9 is a seventh schematic structural diagram of the housing according to the embodiment of the present invention.

Fig. 10 is a plan view of a cover according to an embodiment of the present invention.

Wherein the reference numerals are as follows:

1-a button cell; 2-electric core; 21-a main body portion; 211-a first pole piece; 212-a second pole piece; 213-a membrane; 22-a first tab; 23-a second tab; 3-a housing; 31-a housing; 32-a first structural member; 321-a first bottom wall; 322-a first side wall; 33-a second structural member; 331-a second bottom wall; 332-a second sidewall; 340-clearance holes; 341-a convex part; 350-positioning grooves; 36-a cover body; 360-explosion-proof lines; 37-an insulator; 370-through hole.

Detailed Description

As some terms are used throughout the description and claims to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, and a person skilled in the art can solve the technical problem within a certain error range to substantially achieve the technical effect.

Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the present application, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly, e.g., as a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

The present invention will be described in further detail with reference to the accompanying drawings 1-10, which are not intended to limit the invention.

As shown in fig. 1, a button battery 1 according to an embodiment of the present invention includes a battery cell 2 and a housing 3, and the battery cell 2 is accommodated inside the housing 3.

As shown in fig. 2, the battery cell 2 in some embodiments includes a main body 21 and a first tab 22 and a second tab 23 that are opposite in polarity to each other and lead out from the main body 21. Specifically, the main body 21 is formed by winding a first pole piece 211, a separator 213, and a second pole piece 212 in this order. It is understood that the main body 21 may be formed by sequentially and repeatedly laminating the first pole piece 211, the separator 213, and the second pole piece 212. The battery operates primarily by virtue of metal ions moving between the first pole piece 211 and the second pole piece 212. The first pole piece 211 comprises a first current collector and a first active substance layer, and the first active substance layer is coated on the surface of the first current collector; the first tab 22 is connected to a first current collector. The second tab 212 includes a second current collector and a second active material layer coated on a surface of the second current collector, and the second tab 23 is connected to the second current collector.

Taking a lithium ion battery as an example, the material of the first current collector may be aluminum, the first active material layer includes a first active material, and the first active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The material of the second current collector may be copper, the second active material layer includes a second active material, and the second active material may be carbon, silicon, or the like. The material of the separator 213 may be PP, PE, or the like. The first tab 22 and the second tab 23 are respectively an aluminum strip and a copper nickel plating strip (copper strip and nickel strip), and are welded on the empty foil on the corresponding pole piece by ultrasonic welding.

And (3) insulating non-welding points of the aluminum strip and the copper nickel-plated strip (copper strip and nickel strip), wherein the non-welding points include but are not limited to thermal compounding of PP glue, pasting of insulating gummed paper, coating of insulating gummed water and the like. Since the first tab 22 and the second tab 23 need to be bent after being welded to the cover 36 and the case 31, respectively, the non-welded points are insulated to avoid short circuits caused by tab mistouching. It is to be understood that the first tab 22 and the second tab 23 may be one or more. In the present embodiment, the first tab 22 and the second tab 23 are respectively drawn from different ends of the main body 21.

In the above embodiment, the first tab 22 is electrically connected to the cover 36, and the second tab 23 is electrically connected to the first structural member 32 or the second structural member 33 of the case 31, which is not fixedly connected to the cover 36. The welding method includes, but is not limited to, resistance welding, laser welding, and ultrasonic welding. The welding method includes, but is not limited to, resistance welding, ultrasonic welding, and laser welding.

As shown in fig. 3 to 10, the casing 3 of the button cell 1 of the above embodiment includes a case 31, a cover 36 and an insulator 37. Specifically, the shell 31 includes a first structural member 32 having an opening at one end and a second structural member 33 having an opening at one end, the first structural member 32 is sleeved inside the second structural member 33, the opening direction of the first structural member 32 is the same as that of the second structural member 33, and the first structural member 32 or the second structural member 31 is provided with a clearance hole 340; the cover body 36 covers the opening and is fixedly connected with the first structural component 32 or the second structural component 33 to form a sealed cavity; the insulating member 37 is disposed between the first structural member 32 and the second structural member 33, and is used for insulating the first structural member 32 from the second structural member 33, and the insulating member 37 is provided with a through hole 370 at a position corresponding to the clearance hole 340.

In the embodiment of the present invention, the fixed connection manner of the first structural member 32, the second structural member 33, and the insulating member 37 is a composite connection, and the composite connection manner includes: (1) The first structural member 32, the insulating member 37 and the second structural member 33 are sequentially installed and then compounded in one or more of high-frequency heating, hot pressing, reactive curing and high-temperature sintering. (2) The first structural member 32 and the insulating member 37 are combined with the second structural member 33 after being combined, and the combination method includes but is not limited to spraying, hot pressing, heat radiation, injection molding, high-frequency heating, plastic welding, sputtering, evaporation and the like. The insulating member 37 may be formed in one step, or may be formed by combining insulating materials.

The cover 36 of the present embodiment has a thickness of 0.050mm to 0.3mm and is in the form of a disk.

It should be noted that, the shape and structure of the clearance holes 340 and the through holes 370 are not particularly limited in the embodiment of the present application, and the shapes of the clearance holes 340 and the through holes 370 may be circular, square, triangular, and the like.

The first structural member 32 with the opening at one end is sleeved in the second structural member 33 with the opening at one end, the opening direction of the first structural member 32 is consistent with that of the second structural member 33, the first structural member 32 and the second structural member 33 are fixedly connected together through the insulating member 37, the fixed connection area of the first structural member 32 and the second structural member 33 is increased due to the fact that the first structural member 32 is sleeved in the second structural member 33, the composite effective area of the first structural member 32, the second structural member 33 and the insulating member 37 is increased, packaging reliability is greatly improved, leakage risks of the battery are controlled, meanwhile, due to the fact that the composite effective area is increased, and connection strength between the first structural member 32 and the second structural member 33 is increased. In addition, the insulator 37 of the present application is disposed between the first structural member 32 and the second structural member 33, and the first structural member 32 and the second structural member 33 are bonded, and it is not necessary to squeeze the insulator 37 through the first structural member 32 and the second structural member 33, so that the insulator 37 deforms to achieve the sealing effect, and therefore, compared with a sealing ring for mechanical sealing in the prior art, the insulator 37 can ensure the sealing reliability between the first structural member 32 and the second structural member 33 under the condition of smaller thickness, and short circuit or liquid leakage of the battery due to uneven stress on the sealing region cannot occur.

A clearance hole 340 is provided in either one of the first structural member 32 and the second structural member 33, and a through hole 370 is provided in the insulator 37 at a position corresponding to the clearance hole 340. The clearance hole 340 and the through hole 370 are provided to enable the first tab 22 or the second tab 23 of the battery cell 2 to be electrically connected to an external circuit through the casing 31. If the clearance holes 340 and the through holes 370 are not provided, the first structural member 32 and the second structural member 33 overlap, and therefore, only the tab of one polarity can be electrically connected to the cover 36 or the case 31, and the tab of the other polarity cannot be electrically connected to the cover 36 or the case 31.

In an alternative embodiment of the present application, the first structural member 32 includes a first bottom wall 321 and a first side wall 322 fixedly connected to the first bottom wall 321, the second structural member 33 includes a second bottom wall 331 fixedly connected to a second side wall 332 of the second bottom wall 331, and the first bottom wall 321 or the second bottom wall 331 is provided with a clearance hole 340.

As shown in fig. 3, in an alternative embodiment of the present application, the first bottom wall 321 is provided with a clearance hole 340, the first side wall 322 protrudes out of the opening of the second structural member 33, and the cover 36 covers the opening of the first structural member 32 and is fixedly connected to the first side wall 322.

Because the first structural member 32 and the second structural member 33 are insulated by the insulating member 37, the cover 36 is electrically connected to the first tab 22, and the cover 36 and the first structural member 32 are welded together by the top welding or the side welding, so that the electrical properties of the first structural member 32 and the cover 36 are the same as the electrical properties of the first tab 22, and the first structural member 32 is sleeved inside the second structural member 33, the clearance hole 340 needs to be formed in the first bottom wall 321, so that the second tab 23 can penetrate through the clearance hole 340 and is electrically connected to the second structural member 33, and the electrical property of the second structural member 33 is the same as the electrical property of the second tab 23, thereby ensuring that the battery constitutes a complete backflow.

Furthermore, the first side wall 322 protrudes from the opening of the second structural member 33, i.e. the height of the housing 31 is determined by the height of the first side wall 322, in the case of a constant thickness of the first structural member 32, the second structural member 33 and the insulating member 37. Since the first structural member 32 is fitted in the second structural member 33, the cover 36 is electrically connected to the first tab 22 without contacting the second structural member 33, and therefore the first side wall 322 needs to protrude from the opening of the second structural member 33, and the cover 36 can be hermetically connected to the first structural member 32.

As shown in fig. 5, in an alternative embodiment of the present invention, the second bottom wall 331 is provided with a clearance hole 340, the second side wall 332 protrudes from the opening of the first structural member 32, and the cover 36 covers the opening of the second structural member 33 and is fixedly connected to the second side wall 332.

Because the first structure member 32 and the second structure member 33 are insulated by the insulating member 37, the cover 36 is electrically connected to the first tab 22, and the cover 36 and the second structure member 33 are welded together by the top welding or the side welding, so that the electrical properties of the cover 36 and the second structure member 33 are the same as the electrical properties of the first tab 22, the second tab 23 is electrically connected to the first structure member 32, so that the electrical properties of the second tab 23 are the same as the electrical properties of the first structure member 32, and the first structure member 32 is sleeved inside the second structure member 33, it is necessary to provide the clearance hole 340 on the second bottom wall 331 to enable the external circuit to pass through the clearance hole 340 and be electrically connected to the first structure member 32, thereby ensuring that the battery constitutes a complete reflow.

In addition, the second side wall 332 protrudes from the opening of the first structural member 32, that is, the height of the housing 31 is determined by the height of the second side wall 332 under the condition that the thicknesses of the first structural member 32, the second structural member 33 and the insulating member 37 are constant. Since the cover 36 is electrically connected to the first tab 22 and the first structure 32 is electrically connected to the second tab 23, the electrical characteristics of the cover 36 and the first structure 32 are opposite, and the first structure 32 is sleeved inside the second structure 33, so that the cover 36 does not contact the second structure 33, the second sidewall 332 needs to protrude from the opening of the first structure 32, so that the cover 36 does not contact the first structure 32, and the short circuit of the battery is avoided.

As shown in fig. 7 and 8, in the above embodiment, the first bottom wall 321 is provided with the convex portion 341 at the position corresponding to the clearance hole 340, and the convex portion 341 passes through the clearance hole 340.

Through setting up convex part 341 and wearing out the clearance hole 340 that second structure 33 set up at first diapire 321, and then when second structure 33 is connected with the external circuit electricity, the external circuit need not pass clearance hole 340 again, can directly be connected with convex part 341 electricity, because outside is passing the in-process of clearance hole 340, easily the mistake touches first structure 32 and leads to the battery short circuit, and sets up convex part 341 through first diapire 321, can also be applicable to multiple different application environment better.

The convex portion 341 does not contact the second structure 33, and the shape of the convex portion 341 may be any shape without specific limitation, and the shape of the convex portion 341 may be a cylindrical shape, a square column shape, or the like in this embodiment.

As shown in fig. 8, in an alternative embodiment of the present application, the protrusion 341 is integrally formed with the first bottom wall 321, and the protrusion 341 is a hollow structure.

Specifically, the convex portion 341 may be formed by pressing the first bottom wall 321, or the convex portion 341 may be directly formed by integral reverse molding with the first bottom wall 321 and the first side wall 322 in the process of manufacturing the first structural member 32 by the die. Since the projection 341 has a hollow structure, the fitting space required for welding the second pole ear 23 to the first structural member 32 is reduced, and since the projection 341 has a hollow structure, the second pole ear 23 can be welded to the projection 341 through a cavity of the projection 341 when welding is performed, and the cavity can be used to accommodate a welded structure formed when the second pole ear 23 is welded to the first structural member 32.

As shown in fig. 4, 6, 7 and 9, in an alternative embodiment of the present application, the first sidewall 322 or the second sidewall 332 is provided with a positioning groove 350, and the cover 36 is assembled to the positioning groove 350.

Specifically, a protrusion is disposed on an opening plane of the first sidewall 322 or the second sidewall 332, the protrusion and the opening plane form a positioning groove 350, and the positioning groove 350 is in clearance or interference fit with the cover 36. The inner diameter of the positioning groove 350 is greater than or equal to the outer diameter of the cover 36. Through setting up constant head tank 350, in lid 36 and casing 31 welding process, need not fix a position again, as long as put into constant head tank 350 with lid 36, just can make lid 36 and casing 31 lug weld.

In an alternative embodiment of the present application, as shown in fig. 10, the cover 36 is provided with an explosion-proof line 360.

Specifically, the anti-explosion groove 360 is a groove, and the shape of the groove includes, but is not limited to, an S shape, a V shape, an X shape, and an O shape, and the groove is formed by performing laser etching or punching on the inner surface or the outer surface of the cover body 36, and the depth of the groove can be adjusted according to the capacity of the battery, which is not limited herein. When the battery is out of control due to heat, the internal pressure is increased, and the explosion-proof lines 360 are grooves, namely the thickness of the cover body 36 at the explosion-proof lines 360 is the minimum, so that the cover body 36 is preferentially broken from the explosion-proof lines 360, a pressure relief channel is formed to discharge internal gas, and the safety of the battery is improved.

In an alternative embodiment of the present application, the thickness of the insulator 37 is 0.030-0.1mm. When the thickness of the insulating member 37 is within the above range, the sealing performance and the connection strength between the first structural member 32 and the second structural member 33 can be ensured, and the influence of the insulating member 37 on the space utilization of the battery can be minimized.

Variations and modifications to the above-described embodiments may become apparent to those skilled in the art from the disclosure and teachings of the above description. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious modifications, replacements or variations made by those skilled in the art on the basis of the present invention belong to the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A shell of a button cell is characterized by comprising:

the shell (31), the shell (31) includes a first structural member (32) with an opening at one end and a second structural member (33) with an opening at one end, the first structural member (32) is sleeved inside the second structural member (33), the opening direction of the first structural member (32) is consistent with that of the second structural member (33), and the first structural member (32) or the second structural member (33) is provided with a clearance hole (340);

the cover body (36) covers the opening, and is fixedly connected with the first structural component (32) or the second structural component (33) to form a sealed cavity;

the insulating piece (37) is arranged between the first structural piece (32) and the second structural piece (33) and used for insulating the first structural piece (32) and the second structural piece (33), and through holes (370) are formed in the positions, corresponding to the clearance holes (340), of the insulating piece (37).

2. The housing according to claim 1, wherein the first structural member (32) comprises a first bottom wall (321) and a first side wall (322) fixedly connected to the first bottom wall (321), the second structural member (33) comprises a second bottom wall (331) and a second side wall (332) fixedly connected to the second bottom wall (331), and the first bottom wall (321) or the second bottom wall (331) is provided with a clearance hole (340).

3. The housing according to claim 2, wherein the first bottom wall (321) is provided with the clearance hole (340), the first side wall (322) protrudes from the opening of the second structural member (33), and the cover (36) covers the opening of the first structural member (32) and is fixedly connected to the first side wall (322).

4. The housing according to claim 2, wherein the second bottom wall (331) is provided with the clearance hole (340), the second side wall (332) protrudes from the opening of the first structural member (32), and the cover (36) covers the opening of the second structural member (33) and is fixedly connected to the second side wall (332).

5. The housing according to claim 4, wherein the first bottom wall (321) is provided with a protrusion (341) at a position corresponding to the clearance hole (340), and the protrusion (341) protrudes through the clearance hole (340).

6. The housing according to claim 5, wherein the protrusion (341) is integrally formed with the first bottom wall (321), and the protrusion (341) has a hollow structure.

7. The housing according to claim 2, characterized in that the first side wall (322) or the second side wall (332) is provided with a positioning slot (350), the cover (36) being fitted to the positioning slot (350).

8. Housing according to claim 1, characterized in that the cover (36) is provided with an explosion-proof thread (360).

9. A casing according to claim 1, characterized in that the thickness of the insulating element (37) is 0.030-0.1mm.

10. Button cell battery, characterized in that it comprises a cell (2) and a housing (3) according to any one of claims 1 to 9, said cell (2) being accommodated inside said housing (3).