CN220821735U - Secondary battery, battery pack, and electronic device - Google Patents

Abstract

The utility model provides a secondary battery, a battery pack and an electronic device, wherein the secondary battery comprises: the device comprises a shell, an electrode assembly, a current collecting member, a first sealing ring, an end cover and a second sealing ring; the shell comprises a cylindrical side wall and an opening, and a rolling groove is formed in the side wall at a position close to the opening; the electrode assembly is accommodated in the case; the current collecting component is arranged in the shell and is electrically connected with the electrode assembly, and the current collecting component comprises a shell connecting part which is fixedly connected with one side of the rolling groove, which is away from the electrode assembly; the first sealing ring is clamped between one side of the shell connecting part far away from the axis of the secondary battery and the side wall of the shell; the end cover is arranged on the shell, and the cover seals the opening; the second sealing ring is clamped between the outer periphery of the end cover and the shell, and the second sealing ring is abutted with the first sealing ring. The secondary battery can improve the sealing performance between the sealing ring and the rolling groove and the sealing performance between the end cover and the shell.

Description

Secondary battery, battery pack, and electronic device

Technical Field

The utility model relates to the technical field of batteries, in particular to a secondary battery, a battery pack and electronic equipment.

Background

The secondary battery is mainly composed of a case, an electrode assembly disposed in the case, a current collecting member, an end cap, and the like. Wherein, the end of the shell is generally provided with an opening, and the end cover is sealed at the opening. In the prior art, the sealing method between the end cover and the shell is mainly divided into two types, namely a mechanical sealing type and a laser welding sealing type. Among them, mechanical sealing is widely used because of its high productivity and low investment cost. When the existing secondary battery is subjected to mechanical sealing, a rolling groove is usually required to be machined on the shell, then the sealing ring and the end cover are installed at the position of the rolling groove, and finally the shell at the opening is subjected to mechanical compression, so that the sealing ring is compressed between the end cover and the shell, and the sealing at the opening is realized.

At present, in order to realize conductive connection between a current collecting member and a shell, the current collecting member in the shell is generally lapped on the side wall of a rolling groove along the radial direction, but because the current collecting member cannot be effectively positioned along the radial direction, the lap joint area formed between the current collecting member and the side wall of the rolling groove is unstable, so that the sealing area between the side wall of the rolling groove and a sealing ring is unstable, the sealing ring is easy to have the problem of sealing failure at the position of the rolling groove, the probability of sealing failure between an end cover and the shell is increased, and the safety of the secondary battery is reduced.

Disclosure of utility model

In view of the above drawbacks of the prior art, the present utility model provides a secondary battery, a battery pack, and an electronic device to improve positioning accuracy between a current collecting member and a rolling groove, thereby improving sealing performance between an end cap and a case.

To achieve the above and other related objects, the present utility model provides a secondary battery comprising: the device comprises a shell, an electrode assembly, a current collecting member, a first sealing ring, an end cover and a second sealing ring; the shell comprises a cylindrical side wall and an opening, wherein a rolling groove recessed towards the inside of the shell is formed in the side wall at a position close to the opening, and a flanging part extending towards the axis side of the secondary battery and a connecting part for connecting the flanging part and the rolling groove are further arranged at the opening side; the electrode assembly is accommodated in the case, and the rolling groove restricts movement of the electrode assembly in the case in the height direction of the secondary battery; the current collecting component is arranged in the shell and is electrically connected with the electrode assembly, and the current collecting component comprises a shell connecting part which is fixedly connected with one side of the rolling groove, which is away from the electrode assembly; the first sealing ring is clamped between one side of the shell connecting part far away from the axis of the secondary battery and the side wall of the shell along the radial direction of the secondary battery; the end cover is arranged between the flanging part and the rolling groove and covers the opening; the second sealing ring is clamped between the outer periphery of the end cover and the shell to realize sealing connection between the end cover and the shell, and the second sealing ring is abutted with the first sealing ring.

In an example of the secondary battery of the present utility model, the first seal ring includes a first abutting portion extending in a direction toward the axis of the secondary battery, the first abutting portion abutting against a side of the case connecting portion away from the axis of the secondary battery, and a thickness of the first abutting portion in a height direction of the secondary battery is greater than or equal to a thickness of the case connecting portion.

In an example of the secondary battery of the present utility model, the rolling groove includes a first groove wall on a side facing away from the electrode assembly, and a first rounded corner is formed between a side of the first groove wall facing away from the axis of the secondary battery and the connecting portion; a second round angle is formed on one side of the first sealing ring, facing the connecting part, and the second round angle is at least in butt joint with the part of the first round angle.

In an example of the secondary battery of the present utility model, the outer edge of the end cap is located between the inner edge and the outer edge of the first sealing ring in the radial direction of the secondary battery, and the distance between the outer edge of the end cap and the inner edge of the first sealing ring is 0.1 to 1mm.

In an example of the secondary battery of the present utility model, a first positioning portion is disposed on a side of the first seal ring abutting against the second seal ring, a second positioning portion is disposed on the second seal ring, and the first positioning portion is matched with the second positioning portion.

In an example of the secondary battery of the present utility model, the first positioning portion includes a sinking stage, and the second positioning portion includes a boss that is matched with the sinking stage.

In an example of the secondary battery of the present utility model, the boss is of an annular structure, and an orthographic projection of the boss on the current collecting member covers a welding region between the case connecting portion and the rolling groove in a height direction of the secondary battery.

In one example of the secondary battery of the present utility model, the current collecting member includes a stopper portion formed by extending the case connecting portion toward the electrode assembly side in the height direction of the secondary battery, and the stopper portion is at least partially abutted against the inner side wall of the rolling groove.

In one example of the secondary battery of the present utility model, the second sealing ring includes an annular groove open toward the center side of the electrode assembly, and the outer circumference of the end cap is received in the annular groove.

In one example of the secondary battery of the present utility model, the surfaces of the first seal ring and the second seal ring are at least partially provided with a sealant.

In an example of the secondary battery of the present utility model, the region where the side wall abuts against the first seal ring and the region where the side wall abuts against the second seal ring are both provided with the sealant.

The utility model also provides a battery pack comprising any one of the secondary batteries described above.

The utility model further provides electronic equipment, which comprises the battery pack.

In the secondary battery, the first sealing ring is clamped between the shell connecting part and the side wall, so that the shell connecting part can be positioned in the radial direction, and the stability of the lap joint area between the shell connecting part and the rolling groove in the radial direction can be improved; the size of the sealing contact area between the first sealing ring and the rolling groove in the radial direction is more stable and consistent, and the probability of sealing failure of the first sealing ring at the rolling groove position due to the fact that the sealing contact area is too small is reduced; the sealing performance between the end cover and the shell can be correspondingly improved, and the cycle service life and the charge and discharge performance of the secondary battery are ensured; meanwhile, the second sealing ring is clamped between the outer periphery of the end cover and the shell, so that the end cover and the shell can be sealed; through mutually butt first sealing washer and second sealing washer, realized the sealing connection between the sealing of rolling groove position department and the sealing position of end cover position department to can form twice sealedly in the opening position of casing, set up like this and can further guarantee the sealed effect of casing in the opening part, further guarantee the circulation life and the charge-discharge performance of secondary cell.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are necessary for the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model and that other embodiments may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a three-dimensional overall schematic view of an embodiment of a secondary battery of the present utility model;

Fig. 2 is a partial sectional view of an embodiment of a secondary battery according to the present utility model;

FIG. 3 is an enlarged view of a portion of region F of FIG. 2;

FIG. 4 is a schematic view of a secondary battery according to an embodiment of the present utility model, wherein the opening is not sealed;

FIG. 5 is an enlarged view of a portion of the J area of FIG. 4;

fig. 6 is a schematic view showing an installation position of an electrode assembly in a case in an embodiment of a secondary battery according to the present utility model;

fig. 7 is an isometric view of a mounting position of a first seal ring in a housing in an embodiment of a secondary battery of the utility model;

fig. 8 is a plan view showing a mounting position of a first seal ring in a case in an embodiment of a secondary battery according to the present utility model;

Fig. 9 is a partial sectional view showing the installation position of the first seal ring in the case in an embodiment of the secondary battery according to the present utility model;

FIG. 10 is an enlarged view of a portion of region H of FIG. 9;

fig. 11 is a top view illustrating an installation position between a first sealing ring and a current collecting member in an embodiment of a secondary battery according to the present utility model;

fig. 12 is a side view illustrating an installation position between a first sealing ring and a current collecting member in an embodiment of the secondary battery according to the present utility model;

FIG. 13 is a cross-sectional view taken in the direction K-K of FIG. 12;

FIG. 14 is an enlarged view of a portion of region L of FIG. 13;

Fig. 15 is a schematic view showing an installation position between the first positioning portion and the second positioning portion in an embodiment of the secondary battery according to the present utility model;

FIG. 16 is a schematic view showing the overall structure of an embodiment of a battery pack according to the present utility model;

fig. 17 is a schematic view showing a structure in which the battery pack of the present utility model is mounted on a vehicle.

Description of element reference numerals

100. A secondary battery; 110. a housing; 111. a sidewall; 112. an opening; 113. rolling grooves; 1131. a first groove wall; 114. a first rounded corner; 115. a burring part; 116. a connection part; 117. a first groove; 118. an end wall; 120. an electrode assembly; 121. a first tab; 130. a current collecting member; 131. a housing connection portion; 132. a limit part; 133. a body portion; 134. a tab connection part; 135. a connecting arm; 140. a first seal ring; 141. a first abutting portion; 142. a second rounded corner; 143. a first positioning portion; 1431. a sinking platform; 14311. a first annulus; 14312. a first sidewall; 144. an annular inner wall; 145. an annular outer wall; 146. a sealing body; 150. a second seal ring; 151. a second positioning portion; 1511. a boss; 15111. a second annulus; 15112. a second sidewall; 152. a second groove; 160. an end cap; 200. a battery pack; 210. a case; 211. a first box portion; 212. a second box portion; 300. an electronic device; 310. a working part.

Detailed Description

Other advantages and effects of the present utility model will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present utility model with reference to specific examples. The utility model may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present utility model. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. It is also to be understood that the terminology used in the examples of the utility model is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the utility model. The test methods in the following examples, in which specific conditions are not noted, are generally conducted under conventional conditions or under conditions recommended by the respective manufacturers.

Where numerical ranges are provided in the examples, it is understood that unless otherwise stated herein, both endpoints of each numerical range and any number between the two endpoints are significant both in the numerical range. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs and to which this utility model belongs, and any method, apparatus, or material of the prior art similar or equivalent to the methods, apparatus, or materials described in the examples of this utility model may be used to practice the utility model.

It should be understood that the terms such as "upper," "lower," "left," "right," "middle," and "a" and the like are used in this specification for descriptive purposes only and not for purposes of limitation, and that the utility model may be practiced without materially departing from the novel teachings and without departing from the scope of the utility model.

Referring to fig. 1 to 17, the present utility model provides a secondary battery 100, a battery pack, and an electronic device 300, wherein the secondary battery 100 can improve the positioning problem between a current collecting member 130 and a rolling groove, thereby improving the sealing performance of an end cap 160 at an opening 112 of a case 110, reducing the leakage probability of electrolyte from the opening 112, and improving the safety performance of the secondary battery 100 during use.

Referring to fig. 1 to 5, the structure of the secondary battery 100 will be further described, the secondary battery 100 including: the electrode assembly includes a case 110, an electrode assembly 120, a current collecting member 130, a first sealing ring 140, an end cap 160, and a second sealing ring 150. The case 110 has a receiving chamber formed therein for receiving the electrode assembly 120, an electrolyte (not shown), and other components, and the case 110 may have an opening 112 at one end or may have openings 112 at both ends. The housing 110 may be of various shapes, such as a cylindrical shape, a prismatic shape, etc. The specific dimensions of the case 110 may be determined according to the specific dimensions of the electrode assembly 120, for example, specifications of 46mm in diameter, 80mm in height, 95mm, 120mm, etc. The material of the housing 110 may be various, such as copper, iron, aluminum, steel, aluminum alloy, etc., and in order to prevent the housing 110 from rusting during long-term use, a layer of rust-preventing material, such as metallic nickel, etc., may be plated on the surface of the housing 110.

Referring to fig. 2, 3 and 5, in an example of the secondary battery 100 of the present utility model, the case 110 has a cylindrical structure, the case 110 includes an end wall 118 and a side wall 111 surrounding the end wall 118, the end wall 118 is a closed end, and the opening 112 opposite to the end wall 118 is an open end. The side wall 111 has a rolling groove 113 formed near the opening 112, and the rolling groove 113 is recessed toward the axis line side of the secondary battery 100; the side of the rolling groove 113 facing away from the electrode assembly 120 is provided with a first groove wall 1131; the side wall 111 is further provided with a burring part 115 extending toward the axis of the secondary battery 100 at a position close to the opening 112, a connecting part 116 is further provided between the burring part 115 and the rolling groove 113, and one end of the connecting part 116 is connected to a side of the burring part 115 away from the axis of the secondary battery 100 in the height direction of the secondary battery 100, and the other end of the connecting part 116 is connected to a side of the first groove wall 1131 away from the axis of the secondary battery 100. The specific dimensions of the rolling groove 113, the burring 115, and the connecting portion 116 are determined according to the dimensions of the secondary battery 100, and in this embodiment, are not particularly limited.

As shown in fig. 2, the electrode assembly 120 is accommodated in the case 110. The electrode assembly 120 is a component in the cell where electrochemical reactions occur. The case 110 may contain one or more electrode assemblies 120 therein. The electrode assembly 120 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode current collector; the positive electrode current collector comprises a positive electrode coating area and a positive electrode lug connected to the positive electrode coating area, wherein the positive electrode coating area is coated with a positive electrode active material layer, and the positive electrode lug is not coated with the positive electrode active material layer. The negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector; the negative electrode current collector comprises a negative electrode coating area and a negative electrode tab connected to the negative electrode coating area, wherein the negative electrode coating area is coated with a negative electrode active material layer, and the negative electrode tab is not coated with the negative electrode active material layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The material of the anode current collector may be copper, the anode active material layer includes an anode active material, and the anode active material may be carbon or silicon, or the like. The separator may be made of PP (polypropylene) or PE (polyethylene). In order to protect and insulate the battery cell, the battery cell can be coated with an insulating film, and the insulating film can be synthesized by PP, PE, PET, PVC or other high polymer materials.

Referring to fig. 2 and 6, in an example of the secondary battery 100 of the present utility model, the electrode assembly 120 is hermetically mounted in the case 110, the electrode assembly 120 is disposed between the end wall 118 and the rolling groove 113 in the height direction of the secondary battery 100, and the rolling groove 113 can restrict axial movement of the electrode assembly 120 between the end wall 118 and the rolling groove 113. The electrode assembly 120 is provided with a first tab 121 and a second tab at two ends in a length direction, and polarities of the first tab 121 and the second tab are opposite, wherein the first tab 121 faces the opening 112 side, and the first tab 121 is a negative tab. In other embodiments, the first tab 121 may be a positive tab, and the second tab may be a negative tab.

Referring to fig. 7 to 10, the current collecting member 130 includes a body portion 133, a housing connecting portion 131, and a tab connecting portion 134, the tab connecting portion 134 is disposed in a central region of the body portion 133, the housing connecting portion 131 is disposed around an outer periphery of the tab connecting portion 134, the housing connecting portion 131 is electrically connected to the tab connecting portion 134, and the electrical connection manner may be selected from various manners, for example, may be a welding connection manner, or may be any manner capable of achieving electrical connection between the housing connecting portion 131 and the tab connecting portion 134, such as an integrally formed connection manner; the number and specific structural forms of the case connection parts 131 and the tab connection parts 134 are not limited as long as a stable electrical connection relationship can be formed between the case 110 and the first tab 121. In this embodiment, in order to improve the assembly efficiency, the housing connection portion 131 and the tab connection portion 134 are integrally connected by press forming, and the housing connection portion 131 is provided with a plurality of housing connection portions 131 arranged in an array on the outer periphery of the tab connection portion 134. Tab connection 134 is welded to first tab 121 to achieve electrical connection between current collecting member 130 and electrode assembly 120; the case connecting part 131 is overlapped on the surface of the first groove wall 1131 in the radial direction along the height direction of the secondary battery 100 to achieve electrical connection between the case connecting part 131 and the case 110; in order to ensure the stability of the electrical connection between the housing connection part 131 and the housing 110, in the present embodiment, the housing connection part 131 is welded to the surface of the first groove wall 1131. In other embodiments, the housing connecting portion 131 and the first groove wall 1131 may not be welded and only abut against each other, and the housing connecting portion 131 may be adhered to the surface of the first groove wall 1131 by conductive adhesive.

Referring to fig. 4 and 5, the first sealing ring 140 is disposed inside the case 110 and located at a side of the rolling groove 113 facing away from the electrode assembly 120; the first sealing ring 140 has an annular structure, and the first sealing ring 140 comprises an annular inner wall 144 and an annular outer wall 145; along the radial direction of the secondary battery 100, the annular outer wall 145 abuts against the inner diameter of the case 110, the annular inner wall 144 abuts against the case connecting portion 131 on the side away from the axis of the secondary battery 100, and the first seal ring 140 abuts against the first groove wall 1131 on the side facing the rolling groove 113; and further, the first sealing ring 140 is interposed between the housing connection portion 131 and the sidewall 111 of the housing 110. The cross-sectional shape of the first seal ring 140 may be selected from various shapes, such as an L-shaped cross-section, a rectangular cross-section, or other shaped cross-section, as long as the first seal ring 140 can be stably sandwiched between the housing 110 and the housing connecting portion 131 in the radial direction. Referring to fig. 2 and 3, when the opening is sealed, the sidewall of the opening forms a flange portion 115 and a connecting portion 116 under the action of mechanical pressure, a first groove 117 is formed between the connecting portion 116, the flange portion 115 and the first groove wall 1131, and the outer periphery of the end cover 160 is clamped in the first groove 117, so that the end cover 160 covers the opening 112. The second sealing ring 150 is clamped between the first groove 117 and the outer periphery of the end cover 160, so that the second sealing ring 150 is coated on the outer periphery of the end cover 160, and sealing connection between the end cover 160 and the shell 110 is realized; one side of the second sealing ring 150 facing the first groove wall 1131 is abutted against the first sealing ring 140, so that sealing connection between the first sealing ring 140 and the second sealing ring 150 is realized.

In the present embodiment, when the secondary battery 100 is assembled, the electrode assembly 120 is first mounted in the case 110, and then the side wall 111 of the case 110 near the opening 112 is grooved 113 to position the axial direction of the electrode assembly 120; then, the first sealing ring 140 is installed from the position of the opening 112, so that the first sealing ring 140 is pressed and abutted against the surface of the first groove wall 1131, the annular outer wall 145 is pressed and abutted against the inner wall of the connecting part 116, and the installation and the fixation of the first sealing ring 140 in the shell 110 are further completed; then, the current collecting member 130 is installed into the housing 110 from the opening 112, so that the housing connecting portion 131 is at least partially overlapped on the first groove wall 1131, and meanwhile, one side, far away from the axis of the secondary battery 100, of the housing connecting portion 131 is abutted and pressed on the annular inner wall 144, and radial positioning of the housing connecting portion 131 in the housing 110 is completed; subsequently, welding the lap joint position to fixedly mount the housing connection part 131 on the first groove wall 1131; finally, the second sealing ring 150 is installed in the shell 110, and the second sealing ring 150 is arranged above the first sealing ring 140, at this time, the section of the second sealing ring 150 is of an approximately L-shaped structure, one side wall of the second sealing ring 150 and the first sealing ring 140 below are in contact with each other to be pressed, and the other side wall of the second sealing ring 150 is in contact with the inner surface of the side wall 111 of the shell 110 to be pressed; and then the end cover 160 is arranged in the shell 110, the outer periphery of the end cover 160 is abutted against the second sealing ring 150, finally, the position of the opening 112 is subjected to pier sealing by mechanical force, a flanging part 115 and a connecting part 116 are formed at the position of the opening 112 of the shell 110, and the end cover 160 is fixedly connected at the position of the opening 112 of the shell 110 in a sealing way through the second sealing ring 150, so that the position of the opening 112 of the shell 110 is sealed.

As can be seen from the above-mentioned sealing process of the secondary battery 100, in the embodiment, by providing the first sealing ring 140, positioning of the case connecting portion 131 in the radial direction is achieved, and stability of the overlap area between the case connecting portion 131 and the first groove wall 1131 in the radial direction is improved; the size of the sealing contact area between the first sealing ring 140 and the first groove wall 1131 in the radial direction is more stable and consistent, so that the probability of sealing failure of the first sealing ring 140 on the first groove wall 1131 caused by too small sealing contact area is reduced; the sealability between the end cap 160 and the case 110 is correspondingly improved, and the cycle life and charge and discharge performance of the secondary battery 100 are ensured; meanwhile, by sandwiching the second seal ring 150 between the outer periphery of the end cover 160 and the housing 110, sealing between the end cover 160 and the housing 110 can be achieved, and sealing performance is stable and reliable; meanwhile, the first sealing ring 140 and the second sealing ring 150 are mutually abutted and pressed, so that the upper sealing position and the lower sealing position of the end cover 160 can be in sealing connection to form two seals, the sealing effect of the end cover 160 at the opening 112 can be further ensured, and the cycle service life and the charge and discharge performance of the secondary battery 100 are further ensured.

Referring to fig. 3, 7, 9, 10 and 14, in an example of the secondary battery 100 of the present utility model, the first sealing ring 140 includes a sealing body 146 and a first abutting portion 141; the sealing body 146 is abutted against the inner wall of the connecting portion 116, one side of the sealing body 146 away from the axis of the secondary battery 100 is abutted against the inner wall of the connecting portion 116, one side of the sealing body 146 facing the axis of the secondary battery 100 is connected with the first abutting portion 141, and the connection mode can be integrated connection or adhesive connection, in this embodiment, the first abutting portion 141 and the sealing body 146 are integrated injection-molded connection. The first abutting portion 141 extends in a direction toward the axis of the secondary battery 100, and a side of the first abutting portion 141 facing away from the sealing body 146 abuts against a side of the case connecting portion 131 facing away from the axis of the secondary battery 100. The thickness H1 of the first abutting portion 141 is greater than or equal to the thickness H2 of the case connecting portion 131 in the height direction of the secondary battery 100. The thickness H1 of the first abutting portion 141 refers to a thickness before the opening 112 is sealed, as shown in fig. 13. The arrangement can ensure that the shell connecting part 131 is completely abutted against the side wall of the first abutting part 141 in the thickness direction when the first abutting part 141 abuts against the shell connecting part 131, so that the stability of positioning the first abutting part 141 on the shell connecting part 131 in the radial direction can be improved, and the probability of positioning failure of the first abutting part 141 on the shell connecting part 131 in the process of upsetting the opening 112 is reduced.

Referring to fig. 3, 5, and 14, in an example of the secondary battery 100 of the present utility model, a first rounded corner 114 is formed between a side of the first groove wall 1131 facing away from the axis of the secondary battery 100 and the connection part 116 in the radial direction of the secondary battery 100; the second rounded corner 142 is formed on the side of the first sealing ring 140 facing the connecting portion 116, and the second rounded corner 142 may be formed on the sealing body 146, or may be formed on the first abutting portion 141, or may be formed on the sealing body, or may be formed on the first abutting portion 141, which is not limited specifically; in the present embodiment, the second fillet 142 is formed at the intersection position of the first abutting portion 141 and the sealing body 146 portion 133, and a portion of the second fillet 142 is located at a side of the first abutting portion 141 away from the connecting portion 116, and another portion of the second fillet 142 is located at a side of the sealing body 146 close to the inner wall of the connecting portion 116; the second rounded corner 142 abuts the first rounded corner 114; the manner of abutting may be selected in various ways, for example, the cambered surface of the second rounded corner 142 may be completely abutted against the cambered surface of the first rounded corner 114, or the cambered surface of the second rounded corner 142 may be abutted against a part of the cambered surface of the first rounded corner 114, which is not particularly limited, as long as the abutting force generated between the second rounded corner 142 and the first rounded corner 114 can meet the positioning requirement of the housing connecting portion 131 in the radial direction. The second rounded corner 142, which is arranged on the first sealing ring 140 and is abutted against the first rounded corner 114, enables the first sealing ring 140 to have better bonding performance between the position of the first rounded corner 114 and the side wall 111 of the shell 110, and further improves the sealing performance between the first sealing ring 140 and the side wall 111; meanwhile, the structure that the second rounded corner 142 is abutted against the first rounded corner 114 can also play a role in guiding the deformation of the first sealing ring 140 at the position when the opening 112 is in pier sealing, so that better sealing performance is formed at the position.

Referring to fig. 5, 7, 10 and 14, in an example of the secondary battery 100 according to the present utility model, the outer edge of the end cap 160 is located between the inner edge of the first sealing ring 140 and the outer edge of the first sealing ring 140, i.e., the outer edge of the end cap 160 is located between the annular inner wall 144 and the annular outer wall 145, in the radial direction of the secondary battery 100, the radial distance L between the outer edge of the end cap 160 and the annular inner wall 144 is any value ranging from 0.1 to 1mm, for example, the dimension L may be 0.1mm, 0.5mm, 1mm, or the like. By the arrangement, on one hand, a certain bonding area between the first sealing ring 140 and the first groove wall 1131 in the radial direction can be ensured, so that the positioning accuracy of the first sealing ring 140 on the current collecting member 130 in the radial direction is further improved; on the other hand, the outer edge of the end cover 160 at least exceeds the outer edge of the housing connecting portion 131 by 0.1mm, so that the length of the welding surface between the housing connecting portion 131 and the first groove wall 1131 can be ensured, the stability of the electric connection between the current collecting member 130 and the housing 110 can be ensured, the effective sealing area between the first sealing ring 140 and the first groove wall 1131 can be ensured, and the sealing performance at the position can be ensured.

Referring to fig. 5 and 15, in an example of the secondary battery 100 according to the present utility model, a first positioning portion 143 is disposed on a side of the first sealing ring 140 abutting against the second sealing ring 150, and a second positioning portion 151 matching the first positioning portion 143 is disposed on the second sealing ring 150. The first positioning portion 143 and the second positioning portion 151 may have a bump or a groove structure, or may have any structure such as a taper hole or a taper stand structure, which can be used to position the first positioning portion 143 and the second positioning portion 151 in cooperation with each other. The first positioning portion 143 and the second positioning portion 151 cooperate to achieve positioning, which may be axial positioning between the first positioning portion 143 and the second positioning portion, radial positioning, or both axial and radial positioning. By providing the first positioning portion 143 and the second positioning portion 151 that are mutually engaged, the probability of occurrence of displacement between the first seal ring 140 and the second seal ring 150 can be reduced, and thus the sealing performance at the abutting position between the first seal ring 140 and the second seal ring 150 can be improved. Preferably, in order to further reduce the probability of displacement occurring between the first seal ring 140 and the second seal ring 150, in this embodiment, the first positioning portion 143 and the second positioning portion 151 cooperate to simultaneously achieve positioning of the first seal ring 140 and the second seal ring 150 in the axial and radial directions.

Referring to fig. 5 and 15, in an example of the secondary battery 100 of the present utility model, the first positioning portion 143 includes a sink 1431, the sink 1431 has a ring-shaped structure and is coaxially installed in the case 110 with the secondary battery 100, and the sink 1431 has a first annular surface 14311 and a first sidewall 14312 connected to each other; the second positioning portion 151 includes a boss 1511, where the boss 1511 is of an annular structure, and the boss 1511 has a second annular surface and a second sidewall 15112 that are connected perpendicularly to each other; the first ring surface 14311 and the second ring surface 15111 are abutted against each other along the height direction of the secondary battery 100, so that the first sealing ring 140 and the second sealing ring 150 are positioned in the axial direction; the first sidewall 14312 and the second sidewall 15112 abut against each other in the radial direction of the secondary battery 100, and positioning of the first seal ring 140 and the second seal ring 150 in the radial direction is achieved. By providing the structures of the sinking platform 1431 and the boss 1511, when the boss 1511 is installed corresponding to the sinking platform 1431, the positioning of the first seal ring 140 and the second seal ring 150 in the axial direction and the radial direction can be simultaneously realized; thereby reducing the probability of mutual displacement of the first sealing ring 140 and the second sealing ring 150 in the installation process and the upsetting process, and obtaining better sealing performance at the connection position of the first sealing ring 140 and the second sealing ring 150; meanwhile, the sinking platform 1431 and the boss 1511 are simple in structure, convenient to form and process and reliable in positioning.

It should be noted that, in other embodiments of the present utility model, the boss 1511 and the sinking platform 1431 may not be annular structures, for example, the first positioning portion 143 may include a plurality of sinking platforms 1431, the plurality of sinking platforms 1431 are annularly disposed around the first sealing ring 140, and correspondingly, the second positioning portion 151 includes a plurality of bosses 1511, the plurality of bosses 1511 are annularly disposed around the second sealing ring 150, and the plurality of bosses 1511 are respectively disposed corresponding to the plurality of sinking platforms 1431. By this arrangement, the positioning of the first seal ring 140 and the second seal ring 150 in the axial and radial directions can be achieved at the same time, but the structure is inconvenient to install and the processing and shaping are complicated.

Referring to fig. 4, 5 and 15, in an example of the secondary battery 100 of the present utility model, the boss 1511 has a ring-shaped structure, and an orthographic projection of the boss 1511 on the current collecting member 130 covers a welding region between the case connecting part 131 and the first groove wall 1131 in a height direction of the secondary battery 100. The size of the orthographic projection area of the boss 1511 on the current collecting member 130 is not limited as long as it can cover the welding area between the case connecting part 131 and the first groove wall 1131. In the present embodiment, the width dimension of the second annular surface is larger than the width dimension of the first annular surface 14311 along the radial direction of the secondary battery 100, and one side of the second annular surface away from the axis of the secondary battery 100 is abutted against the first annular surface 14311, forming a first supporting position under the second annular surface 15112; one side of the second annular surface 15112, which is close to the axis of the secondary battery 100, abuts against one side of the case connecting part 131, which faces away from the electrode assembly 120, and a second support position is formed below the second annular surface 15112; in the radial direction of the secondary battery 100, a welding area between the case connecting part 131 and the first groove wall 1131 is located between the first support position and the second support position. By means of the arrangement, on one hand, after the opening 112 of the shell 110 is completely sealed, a larger bonding area can be formed between the second sealing ring 150 and the shell connecting portion 131, the probability of displacement of the shell connecting portion 131 in the use process can be reduced, and further the positioning accuracy of the shell connecting portion 131 and the first groove wall 1131 in the radial direction can be further improved; on the other hand, after the opening 112 is completely sealed, the second sealing ring 150 may completely cover the welding area between the housing connection portion 131 and the first groove wall 1131, so as to reduce the probability of the welding area contacting with the electrolyte, reduce the probability of the welding area being corroded by the electrolyte, and facilitate to improve the stability of the conductive connection between the current collecting member 130 and the housing 110.

Referring to fig. 7 to 13, in an example of the secondary battery 100 of the present utility model, the current collecting member 130 further includes a connection arm 135 and a limiting portion 132, one end of the connection arm 135 is connected to the case connection portion 131, the other end of the connection arm 135 is connected to the tab connection portion 134, the limiting portion 132 is formed by extending the case connection portion 131 toward the electrode assembly 120 side in the height direction of the secondary battery 100, and the limiting portion 132 is at least partially abutted against the inner sidewall of the rolling groove 113. The limiting part 132 and the shell connecting part 131 can be integrally formed or welded, so long as the requirement of the connecting strength of the limiting part 132 can be met; in the present embodiment, the limiting portion 132 and the housing connecting portion 131 are integrally connected by press forming, so that the assembly time between the limiting portion 132 and the housing connecting portion 131 can be saved, and the assembly efficiency of the current collecting member 130 can be improved. The specific structure of the stopper 132 is not limited, and may be, for example, a flat plate structure, a cylindrical structure, an arc plate structure, or any other structure capable of abutting against the inner side wall of the rolling groove 113. Preferably, in order to facilitate molding and reduce production cost, in an example of the present utility model, the limiting portion 132 is a flat plate structure. The number and specific positions of the limiting portions 132 are not limited, but preferably, in the present embodiment, two limiting portions 132 are disposed on each housing connecting portion 131, and the two limiting portions 132 are located on two sides of the connecting arm 135 respectively. By the arrangement, the two sides of the shell connecting part 131 can form supporting points, so that better positioning strength and positioning accuracy can be obtained in the positioning process.

Through set up spacing portion 132 on casing connecting portion 131, can play radial spacing effect at casing connecting portion 131 in-process of pushing down, can reduce the radial displacement volume of casing connecting portion 131 on first cell wall 1131 to the extrusion force that radial direction produced between casing connecting portion 131 and first sealing washer 140 can be reduced, so can reduce first sealing washer 140 because the extrusion force is too big and the probability of being compressed down, improves first sealing washer 140's life.

Referring to fig. 2 and 3, in an example of the secondary battery 100 of the present utility model, after the opening 112 is sealed by pier, the second sealing ring 150 is clamped in the first groove 117, and a second groove 152 is formed on a side of the second sealing ring 150 facing the axis of the secondary battery 100; the opening of the second groove 152 faces to one side of the axis of the secondary battery 100, and the outer periphery of the end cover 160 is clamped in the second groove 152 and is pressed against the inner wall of the second groove 152. By this arrangement, the upper and lower surfaces and the peripheral wall of the peripheral edge of the end cap 160 are in pressing contact with the second seal ring 150, so that the end cap 160 can obtain a good sealing effect at the opening 112.

To further secure the sealing effect of the first and second sealing rings 140 and 150, in an example of the secondary battery 100 of the present utility model, the surfaces of both the first and second sealing rings 140 and 150 are coated with a sealant. The type of the sealant may be selected from various types, for example, silicone sealant, polyurethane sealant, butyl sealant, etc., and preferably, in this embodiment, the sealant is a silicone sealant. The positions of the sealant coated on the surfaces of the first sealing ring 140 and the second sealing ring 150 may be selected, for example, the sealant may be coated on all the surfaces formed by the first sealing ring 140 and the second sealing ring 150, the sealant may be coated only on the surfaces of the first sealing ring 140 and the second sealing ring 150, which are respectively connected with the side wall 111 of the housing 110, or the sealant may be coated on the surfaces of the first sealing ring 140 and the second sealing ring 150, which are respectively abutted against the first groove wall 1131; this is not particularly limited. In this embodiment, the first seal ring 140 is coated with a sealant on the surface that contacts the first groove wall 1131 and the inner wall of the connecting portion 116, and the second seal ring 150 is coated with a sealant on the positions that contact the first groove wall 1131, the inner wall of the connecting portion 116, and the inner wall of the flange portion 115. Because the sealant has a certain elasticity after solidification, when there is an installation gap between the first sealing ring 140 and the side wall 111 of the housing 110, and between the second sealing ring 150 and the side wall 111 of the housing 110, the sealant can fill the gap, and eliminate the gap, thereby improving the sealing performance between the first sealing ring 140 and the second sealing ring 150 and the side wall 111.

In another embodiment of the present utility model, the abutting position of the second sealing ring 150 and the end cover 160 is coated with sealant, so that the second sealing ring 150 and the end cover 160 can be bonded and connected together before being put into the shell, and then the installation of the second sealing ring 150 in the shell 110 is realized by installing the end cover 160; therefore, the mounting efficiency of the second sealing ring 150 in the case 110 can be improved, and thus the assembly efficiency of the secondary battery 100 can be improved.

Referring to fig. 11, in an example of the secondary battery 100 of the present utility model, the surfaces of the first sealing ring 140 and the second sealing ring 150 are not coated with the sealant, and the sealant is coated on the inner walls of the first groove wall 1131, the first rounded corner 114, the connection part 116, and the flange part 115. By this arrangement, the installation gaps between the first seal ring 140 and the side wall 111 of the case 110 and between the second seal ring 150 and the side wall 111 of the case 110 can be eliminated, and the sealing performance between the first seal ring 140 and the second seal ring 150 and the side wall 111 can be improved; meanwhile, the shell 110 is coated with the sealant, so that the gluing operation is more convenient, and the gluing efficiency is higher.

Referring to fig. 16, in an embodiment of a battery pack 200 of the present utility model, the battery pack 200 includes a case 210 and at least one secondary battery 100; the case 210 includes a first case 210 part and a second case 210 part, the first case 210 part and the second case 210 part are covered with each other to form an accommodating space, the plurality of secondary batteries 100 are accommodated in the accommodating space, and the plurality of secondary batteries 100 may be connected in series and/or parallel. The battery pack 200 may be, for example, a battery module, a battery pack, or the like.

Referring to fig. 17, in an example of the electronic device 300 of the present utility model, the electronic device 300 includes a working portion 310 and a battery pack 200, and the working portion 310 is electrically connected to the battery pack 200 to obtain power support. The working part 310 may be a unit part capable of taking the electric power of the battery pack 200 and making a corresponding work, such as a blade rotation unit of a fan, a dust suction working unit of a dust collector, a wheel driving unit in an electric vehicle, etc. The electronic device 300 may be a vehicle, a cellular phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the present utility model is not particularly limited to the above-described electronic device 300. In an embodiment of the electronic device 300 of the present utility model, the electronic device 300 is a vehicle, the working portion 310 is a body of the vehicle, and the battery pack 200 is fixedly mounted on the body, so as to provide driving force for the vehicle, thereby realizing running of the vehicle.

According to the secondary battery 100, the positioning of the shell connecting part 131 in the radial direction is realized by arranging the first sealing ring 140, and the stability of the lap joint area between the shell connecting part 131 and the first groove wall 1131 in the radial direction is improved; the size of the sealing contact area between the first sealing ring 140 and the first groove wall 1131 in the radial direction is more stable and consistent, so that the probability of sealing failure of the first sealing ring 140 on the first groove wall 1131 caused by too small sealing contact area is reduced; the sealability between the end cap 160 and the case 110 is correspondingly improved, and the cycle life and charge and discharge performance of the secondary battery 100 are ensured; meanwhile, by sandwiching the second seal ring 150 between the outer periphery of the end cover 160 and the housing 110, sealing between the end cover 160 and the housing 110 can be achieved, and sealing performance is stable and reliable; meanwhile, the first sealing ring 140 and the second sealing ring 150 are mutually abutted and pressed, so that the upper sealing position and the lower sealing position of the end cover 160 can be in sealing connection to form two seals, the sealing effect of the end cover 160 at the opening 112 can be further ensured, and the cycle service life and the charge and discharge performance of the secondary battery 100 are further ensured. Therefore, the utility model effectively overcomes some practical problems in the prior art, thereby having high utilization value and use significance. The above embodiments are merely illustrative of the principles of the present utility model and its effectiveness, and are not intended to limit the utility model. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the utility model. Accordingly, it is intended that all equivalent modifications and variations of the utility model be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims (13)

1. A secondary battery, characterized by comprising:

The shell comprises a cylindrical side wall and an opening, wherein a rolling groove recessed towards the inside of the shell is formed in the side wall at a position close to the opening; the opening side is also provided with a flanging part extending to the axis side of the secondary battery and a connecting part connecting the flanging part and the rolling groove;

An electrode assembly accommodated in the case, the rolling groove restricting movement of the electrode assembly in the case in a height direction of the secondary battery;

The current collecting member is arranged in the shell and is electrically connected with the electrode assembly, the current collecting member comprises a shell connecting part, and the shell connecting part is fixedly connected with one side of the rolling groove, which is away from the electrode assembly;

A first seal ring interposed between a side of the case connecting portion, which is away from the axis of the secondary battery, and a side wall of the case in a radial direction of the secondary battery;

The end cover is arranged between the flanging part and the rolling groove and covers the opening;

The second sealing ring is clamped between the outer periphery of the end cover and the shell so as to realize sealing connection between the end cover and the shell, and the second sealing ring is abutted with the first sealing ring.

2. The secondary battery according to claim 1, wherein the first seal ring includes a first abutting portion that extends toward the direction of the secondary battery axis, the first abutting portion abuts against a side of the case connecting portion away from the secondary battery axis, and a thickness of the first abutting portion in a height direction of the secondary battery is greater than or equal to a thickness of the case connecting portion.

3. The secondary battery according to claim 1, wherein the rolling groove includes a first groove wall on a side facing away from the electrode assembly, a first rounded corner being formed between a side of the first groove wall facing away from the axis of the secondary battery and the connecting portion; and a second round angle is formed on one side of the first sealing ring, which faces the connecting part, and the second round angle is at least in butt joint with the part of the first round angle.

4. The secondary battery according to claim 1, wherein an outer edge of the end cap is located between an inner edge and an outer edge of the first sealing ring in a radial direction of the secondary battery, and a distance between the outer edge of the end cap and the inner edge of the first sealing ring is 0.1 to 1mm.

5. The secondary battery according to claim 1, wherein a first positioning portion is provided on a side of the first seal ring that abuts against the second seal ring, and a second positioning portion corresponding to the first positioning portion is provided on the second seal ring.

6. The secondary battery according to claim 5, wherein the first positioning portion includes a sinking table, and the second positioning portion includes a boss that is matched with the sinking table.

7. The secondary battery according to claim 6, wherein the boss is of an annular structure, and an orthographic projection of the boss on the current collecting member covers a welding area between the case connecting portion and the rolling groove in a height direction of the secondary battery.

8. The secondary battery according to claim 1, wherein the current collecting member includes a stopper portion formed by the case connecting portion extending toward the electrode assembly side in the height direction of the secondary battery, and the stopper portion is at least partially abutted against an inner side wall of the rolling groove.

9. The secondary battery according to claim 1, wherein the second sealing ring includes a second groove opening toward a center side of the electrode assembly, and an outer peripheral edge of the end cap is received in the second groove.

10. The secondary battery according to claim 1, wherein surfaces of the first seal ring and the second seal ring are at least partially provided with a sealant.

11. The secondary battery according to claim 1, wherein the region where the side wall abuts against the first seal ring and the region where the side wall abuts against the second seal ring are each provided with a sealant.

12. A battery pack comprising the secondary battery according to any one of claims 1 to 11.

13. An electronic device comprising the battery pack of claim 12.