CN217426788U

CN217426788U - Pole piece and battery cell

Info

Publication number: CN217426788U
Application number: CN202220130158.0U
Authority: CN
Inventors: 廖科军; 张叶; 邹浒
Original assignee: Zhuhai Cosmx Battery Co Ltd
Current assignee: Zhuhai Cosmx Battery Co Ltd
Priority date: 2022-01-18
Filing date: 2022-01-18
Publication date: 2022-09-13
Anticipated expiration: 2032-01-18

Abstract

The application provides a pole piece and a battery cell. The pole piece includes: a pole piece body; the pole lug is connected with the pole piece body and is provided with a bottom edge and a top edge, the bottom edge of the pole lug is connected with the pole piece body, and the width of the bottom edge of the pole lug is larger than that of the top edge of the pole lug. The application provides a pole piece can solve the technical problem that the circumstances of turning over appears in the winding process in utmost point ear.

Description

Pole piece and battery cell

Technical Field

The application relates to the technical field of batteries, in particular to a pole piece and a battery core.

Background

The lithium ion battery is widely applied to electronic equipment such as mobile phones, tablet computers, notebook computers or wearable equipment. With the advancement and development of science and technology, in addition to the performance requirements of lithium ion batteries such as safety, people put forward higher requirements on electronic devices, such as high rate or fast charge. The multi-tab structure of the battery cell is an important way for realizing high-rate charge and discharge, and the high-rate charge and discharge of the battery can be realized by increasing the number of tabs of the pole piece.

However, the multi-tab structure has problems while achieving high-rate charge and discharge. Due to the fact that the number of the tabs is large, the requirement for equipment manufacturing process is high. In the high-speed winding process of the winding process, the tabs are easy to be folded under the action of centrifugal force, and the like, so that the tabs after being folded can cause short circuit risks in the battery cell. When the short circuit occurs in the battery core, the battery core has the possibility of explosion caused by fire, and the safety performance of the battery is influenced.

SUMMERY OF THE UTILITY MODEL

The application provides a pole piece and electric core to solve the technical problem that the circumstances of turning over appears in utmost point ear in the coiling process.

The application provides a pole piece, it includes:

a pole piece body;

the lug is connected with the pole piece body and is provided with a bottom edge and a top edge, the bottom edge is connected with the pole piece body, and the width of the bottom edge is larger than that of the top edge.

The pole piece of this application embodiment includes pole piece body and utmost point ear. The pole lug extends out from one side of the pole piece body. The pole ear is in a non-equal width structure. Because the width of the bottom edge is greater than that of the top edge, the width of the root area where the tab is connected with the pole piece body is relatively increased, and therefore the deformation resistance of the root area, close to the pole piece body, on the tab can be improved. In the winding process, the tab can bear a larger centrifugal force, so that the possibility of bending of the root region of the tab can be effectively reduced, the possibility of bending of the whole tab is reduced, and the improvement of the use safety of the wound battery cell is facilitated.

In some realizable modes, the width of the tab is decreased progressively along the direction far away from the pole piece body, so that the width change rule of the tab is orderly, the overall transition is smooth, the integral rigidity of the tab is favorably ensured, and the integral tab has good deformation resistance.

In some realizable forms, at least a portion of the tab is a trapezoidal section that is connected to the pole piece body. The trapezoidal section of the tab has good rigidity and high stability, so that the tab can bear large centrifugal force without folding, and the possibility of folding the whole tab in a winding process is reduced.

In some realizable forms, of the two waist sides of the trapezoidal segment, the included angle between the waist side and the bottom side is S, wherein at least one included angle S has a value in the range of 45 ° < S < 90 °.

In some realizable forms, the trapezoidal segments are right-angled trapezoids.

In some realizable forms, the trapezoidal segments are isosceles trapezoids. The included angle between two waist limits of trapezoidal section and the pole piece body equals to two waist limits are symmetrical structure for the center of utmost point ear, are favorable to improving the holistic stability of utmost point ear, are difficult for taking place to turn over under the centrifugal force effect.

In some realizable forms, the tab is trapezoidal in shape as a whole.

In some realizable forms, the tab further includes an extension section connected to the trapezoidal section, and the trapezoidal section has a width greater than a width of the extension section.

In some realizable forms, the epitaxial segment is rectangular. The design mode that the section of extending is the rectangle is convenient for use laser cutting technology processing manufacturing whole utmost point ear, is favorable to reducing the processing degree of difficulty of utmost point ear.

In some implementations, the ratio of the width of the bottom edge to the width of the top edge is K, where 1 < K ≦ 10. If the ratio K of the width D1 of the bottom edge to the width D2 of the top edge is greater than 10, on one hand, the width D1 of the bottom edge of the tab is too large, and in the finished battery cell, the bottom edges of the tabs in the two tab groups contact with each other, so that the battery cell may be short-circuited; on the other hand, can make the whole too flat in the width direction of pole piece body of utmost point ear, the size that the utmost point ear stretches out along the width direction of pole piece body is less, has the utmost point ear group and the electrode terminal that form or the utmost point ear group and the difficult possibility of switching part welding that forms to the utmost point ear group and electrode terminal or utmost point ear group and switching part weld not be convenient for.

In some realizable modes, the lug is provided with the reinforcing ribs, so that the integral rigidity and flexibility of the lug can be effectively improved, the integral deformation resistance of the lug is improved, the possibility of shaking or swinging of the lug in the winding process is reduced, and the possibility of folding the lug under the centrifugal action in the process of winding to form a battery cell is also reduced.

The application also provides a battery cell, which comprises the pole piece of the embodiment.

Drawings

In order to more clearly illustrate the technical solutions in the present application or prior art, the drawings used in the following embodiments or description of the prior art will be briefly described, and it is easy to see that the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a battery according to an embodiment of the present application;

fig. 2 is a partially exploded view of a battery according to an embodiment of the present disclosure;

FIG. 3 is a schematic view of a partial structure of a pole piece according to an embodiment of the present disclosure;

FIG. 4 is an enlarged view of the point A in FIG. 3;

fig. 5 is a schematic view of a connection structure between a battery cell and an adapter component according to an embodiment of the present application;

FIG. 6 is a schematic view of a partial structure of a pole piece according to another embodiment of the present disclosure;

FIG. 7 is a schematic view of a partial structure of a pole piece according to yet another embodiment of the present application;

FIG. 8 is an enlarged view of the point B in FIG. 7;

FIG. 9 is a schematic view of a partial structure of a pole piece according to yet another embodiment of the present application;

fig. 10 is a schematic view of a connection structure between a battery cell and an adapter component according to another embodiment of the present application;

FIG. 11 is a schematic view of a partial structure of a pole piece according to another embodiment of the present application;

fig. 12 is a schematic partial structure diagram of a pole piece according to yet another embodiment of the present application.

Description of the reference numerals:

10. a battery;

20. a housing;

30. an electric core; 30a, a polar ear group;

31. pole pieces;

311. a pole piece body; 311a, edges;

312. a tab; 312a, bottom edge; 312b, top edge; 3121. a trapezoidal section; 3121a, waist edge;

3122. an extension section; 3123. reinforcing ribs;

40. an electrode terminal;

50. a switching component;

x, length direction;

y, width direction.

Detailed Description

Fig. 1 schematically shows the structure of a battery 10 of an embodiment of the present application. Referring to fig. 1, the battery 10 according to the embodiment of the present disclosure may be charged or discharged for recycling. The battery 10 of the embodiment of the present application has a characteristic of high-rate charge and discharge, and thus has a wide application in electronic devices. For example, the electronic device may be, but is not limited to, a cell phone, a tablet, a laptop, a wearable device, a wireless headset, a smart watch, or a smart bracelet. The battery 10 of the embodiment of the present application may be a hard-shell battery or a pouch battery, which is not limited in the embodiment of the present application. The battery 10 may be a lithium ion battery or a lithium sulfur battery, which is not limited in the embodiments of the present application.

Fig. 2 schematically shows a partially exploded structure of the battery 10 of the embodiment of the present application. Referring to fig. 2, a battery 10 according to an embodiment of the present disclosure includes a case 20, a battery cell 30 disposed in the case 20, and an electrode terminal 40 led out from the case 20.

The case 20 of the embodiment of the present application has a space for accommodating the battery cell 30 and the electrolyte. The casing 20 may protect the battery cell 30. Illustratively, the material of the housing 20 may be, but is not limited to, aluminum or plastic.

The battery cell 30 of the embodiment of the present application has two pole ear groups 30 a. One of the two tab groups 30a is a positive tab group, and the other is a negative tab group. Each of the tab sets 30a includes a plurality of tabs. Illustratively, the two pole ear groups 30a may be located on the same side, i.e., lead from the same side. The two tab groups 30a are electrically connected to the two electrode terminals 40, respectively. The battery 10 may be charged or discharged through the electrode terminals 40. Illustratively, the tab set 30a may be welded to the electrode terminal 40. For example, the tab group 30a may be welded to the electrode terminal 40 using a laser welding process or an ultrasonic welding process. Alternatively, the electrode tab group 30a may be electrically connected to the electrode terminal 40 through the interposer 50. The pole piece group 30a and the electrode terminal 40 may be welded to the adaptor part 50, respectively. The interposer component 50 may be an interposer.

The battery cell 30 includes two pole pieces and a diaphragm. The two pole pieces have opposite polarities, namely one is a positive pole piece, and the other is a negative pole piece. The two pole pieces are respectively arranged on two sides of the diaphragm. The separator has an electrical insulating property. The diaphragm is used for insulating and isolating the two pole pieces, and the two pole pieces are prevented from being contacted with each other to generate short circuit. In the embodiment where the battery 10 is a lithium ion battery, the separator has a large number of through pores, and has good permeability to lithium ions, thereby ensuring that the lithium ions can pass through freely.

The two pole pieces and the diaphragm can be wound by a winding device to form the battery core 30. In the process of winding the battery cell 30 in the winding process of the embodiment of the application, the two pole pieces and the diaphragm need to be conveyed to the reel by using the conveying shaft. The reel can simultaneously wind the two pole pieces and the separator to form the cell 30 meeting performance requirements. In the process of winding to form the battery core 30, the rotating speeds of the conveying shaft and the winding shaft are relatively high, so that centrifugal force is generated at the pole lugs of the pole pieces. Because the whole rectangle that is of utmost point ear among the correlation technique for the width of utmost point ear does not change, and consequently the root zone's of utmost point ear resistance to deformation ability is relatively poor, thereby under the effect of centrifugal force, the root zone of utmost point ear appears buckling easily, leads to the whole risk that has the discount of utmost point ear.

When the battery cell 30 is formed by winding, if the tab is folded, the folded tab may overlap with another pole piece or tab with opposite polarity in the wound battery cell 30, so that the battery cell 30 is short-circuited, and the safety of the battery cell 30 in the use process is affected.

The structural design of the pole piece in the battery cell 30 of the embodiment of the application can effectively solve the technical problem. The root region anti deformability of the utmost point ear of pole piece is stronger, effectively reduces in the coiling process, and the root region of utmost point ear appears buckling easily and leads to the whole possibility that has the discount of utmost point ear.

The following explains an implementation manner of the pole piece 31 provided in the embodiment of the present application.

Fig. 3 schematically shows a partial structure of the pole piece 31 of the embodiment of the present application. Referring to fig. 3 and 4, the pole piece 31 of the embodiment of the present application includes a pole piece body 311 and a pole tab 312.

The pole piece 31 has a plurality of tabs 312. The tabs 312 located on the same side of the pole piece body 311 are disposed at intervals along the length direction X of the pole piece body 311. The tab 312 on the pole piece 31 is formed by cutting off excess material from the sheet metal blank by a cutting process. Illustratively, the tab 312 is formed by cutting a blank of sheet metal material using a laser die cutting process.

The material of the sheet metal blank may be, for example, copper or aluminum. Illustratively, the tab 31 formed by processing a metal sheet blank made of copper may be used as the negative electrode sheet, and the tab 31 formed by processing a metal sheet blank made of aluminum may be used as the positive electrode sheet.

The tab 312 is attached to the pole piece body 311. Illustratively, the tab 312 is of unitary construction with the pole piece body 311. The pole piece body 311 includes an active material layer, and the tab 312 is not provided with an active material layer. For example, when the pole piece 31 is used as a positive pole piece, the active material may be lithium cobaltate, lithium iron phosphate, or ternary lithium or lithium manganate. When the pole piece 31 is used as a negative pole piece, the negative pole piece can be one or more of graphite, hard carbon, soft carbon, silicon and silicon-based materials.

One side of the pole piece body 311 is provided with a tab 312. Illustratively, the pole piece body 311 has a predetermined width. Along the width direction Y of the pole piece body 311, one side of the pole piece body 311 is provided with a plurality of tabs 312.

When the pole piece body 311 is in the expanded state, the plurality of tabs 312 are arranged at intervals along the longitudinal direction X of the pole piece body 311. The length direction X of the pole piece body 311 is perpendicular to the width direction Y of the pole piece body 311. In the winding process, the pole piece 31 is conveyed to a reel along the longitudinal direction X of the pole piece body 311. The pole piece body 311 has a longitudinal direction X identical to the conveying direction of the pole piece 31. The width direction Y of the pole piece body 311 is the same as the axial direction of the reel. In the completely wound battery cell 30, a plurality of tabs 312 located on the same side of the pole piece body 311 may be stacked on each other to form a pole tab group 30 a.

Tab 312 has a bottom edge 312a and a top edge 312 b. The bottom and

top edges

312a, 312b of the tab 312 are spaced apart in a direction away from the pole piece body 311. The direction away from the pole piece body 311 is parallel to the width direction Y of the pole piece body 311. The bottom edge 312a of tab 312 is attached to the pole piece body 311 and the top edge 312b of tab 312 is spaced from the pole piece body 311. The width D1 of the bottom edge 312a of tab 312 is greater than the width D2 of the top edge 312b of tab 312 so that the overall width of tab 312 varies and is not of a uniform width configuration. The width of the tab 312 decreases in a direction away from the pole piece body 311.

Note that the width D1 of the bottom edge 312a of the tab 312 and the width D2 of the top edge 312b of the tab 312 may be measured along the length direction X of the pole piece body 311.

The pole piece 31 of the embodiment of the present application includes a pole piece body 311 and a tab 312. A tab 312 extends from one side of the pole piece body 311. The tabs 312 are of unequal width. Since the width D1 of the bottom edge 312a is greater than the width D2 of the top edge 312b, the width of the root area of the tab 312 connected to the pole piece body 311 is relatively increased, so as to improve the deformation resistance of the root area of the tab 312 near the pole piece body 311. In the winding process, the tab 312 can bear a large centrifugal force, so that the possibility of bending of the root region of the tab 312 can be effectively reduced, the possibility of bending of the whole tab 312 is reduced, and the improvement of the use safety of the wound battery cell 30 is facilitated.

In some realizable modes, the width of the tab 312 is decreased progressively along the direction far away from the pole piece body 311, so that the width change rule of the tab 312 is orderly, the overall transition is smooth, the integral rigidity of the tab 312 is favorably ensured, and the integral tab 312 has good deformation resistance.

In some realizable manners, at least a portion of the tab 312 is a trapezoidal section 3121. The trapezoidal section 3121 is connected to the pole piece body 311. The edge of the trapezoidal section 3121 of the tab 312 close to the pole piece body 311 is the edge with larger width. The trapezoidal section 3121 of the tab 312 forms the bottom edge 312a of the tab 312 near the edge of the pole piece body 311. The trapezoidal section 3121 of the tab 312 may increase the width of the root region of the tab 312. The trapezoidal section 3121 of the tab 312 has good rigidity and high stability, so that the tab can bear a large centrifugal force without folding, and the possibility that the entire tab 312 is folded in the winding process is reduced.

In some realizable manners, the trapezoidal section 3121 has two waist edges 3121a along the length direction X of the pole piece body 311. Along the length direction X of the pole piece body 311, the two waist edges 3121a of the trapezoidal section 3121 are disposed at intervals, that is, there is a gap between the two waist edges 3121 a. In the two waist edges 3121a of the trapezoidal section 3121, an included angle between the waist edge 3121a and the bottom edge 312a is S, wherein at least one included angle S has a value range of 45 ° < S < 90 °, so that the waist edge 3121a is a bevel edge inclined relative to the pole piece body 311. Illustratively, the included angle S between at least one waist edge 3121a of the two waist edges 3121a of the trapezoid section 3121 and the bottom edge 312a may be 50 °, 60 °, 70 °, or 80 °, which is not limited in the embodiments of the present application.

The pole piece body 311 has two opposite edges 311a along the width direction Y of the pole piece body 311. Illustratively, the edge 311a of the pole piece body 311 is a straight edge extending along the length direction X of the pole piece body 311. It should be noted that, along the width direction Y of the pole piece body 311, the bottom edge 312a may be flush with the edge 311a of the pole piece body 311.

In some realizable manners, fig. 5 schematically illustrates a connection structure of the battery cell 30 and the adaptor member 50 according to an embodiment. Referring to fig. 5, after the winding of the battery core 30 is completed, a welding process may be used to weld the tab group 30a to the adaptor component 50. The adapter part 50 and the pole piece group 30a are overlapped with each other in advance, and then welding is performed in the overlapping area using a welding device. Illustratively, the pole ear set 30a may be welded to the adapter member 50 using a laser welding process or an ultrasonic welding process. Illustratively, the stiffness of the interposer component 50 is greater than the overall stiffness of the pole ear set 30 a. The material of the interposer 50 may be copper or aluminum. If the included angle S between at least one waist edge 3121a and the bottom edge 312a in the trapezoidal section 3121 is less than or equal to 45 °, the entire trapezoidal section 3121 is relatively flat in the width direction Y of the pole piece body 311, which results in a small size of the tab 312 protruding from the pole piece body 311 in the width direction Y of the pole piece body 311, and there is a possibility that the formed tab group 30a is difficult to be welded to the electrode terminal 40 or the tab group 30a is difficult to be welded to the adapter part 50.

In some examples, referring to fig. 4, the trapezoidal section 3121 is a right angle trapezoid. An included angle S between one waist edge 3121a of the trapezoidal section 3121 and the bottom edge 312a is 90 °, so that the waist edge 3121a is perpendicular to the edge 311a of the pole piece body 311. The angle S between the other waist edge 3121a of the trapezoidal section 3121 and the bottom edge 312a is greater than 45 ° and less than 90 °, so that the waist edge 3121a intersects with the edge 311a of the pole piece body 311.

In other examples, fig. 6 schematically illustrates a partial structure of the pole piece 31 of an embodiment. Referring to fig. 6, the trapezoidal section 3121 is an isosceles trapezoid. The included angle S between the two waist edges 3121a of the trapezoid section 3121 and the bottom edge 312a is equal, so that the two waist edges 3121a are symmetrical structures relative to the center of the tab 312, which is beneficial to improving the overall stability of the tab 312, and the tab is not easy to turn over under the action of centrifugal force. The two waist edges 3121a of the trapezoidal section 3121 each form an angle S with the bottom edge 312a that is greater than 45 ° and less than 90 °. Illustratively, the included angle S between each of the two waist edges 3121a of the trapezoid section 3121 and the bottom edge 312a may be 50 °, 60 °, 70 °, or 80 °, which is not limited in the embodiments of the present application.

In some realizable manners, the tab 312 is entirely trapezoidal in shape. The bottom and

top edges

312a, 312b of tab 312 may each be straight. In some examples, the tab 312 may have a right-angled trapezoidal shape as a whole. In the completely wound battery core 30, in the two tab groups 30a, the straight edge of one tab group 30a faces the straight edge of the other tab group 30a, so as to be beneficial to reducing the possibility that the tabs 312 in the two tab groups 30a are dislocated to cause the two tab groups 30a to overlap with each other. In other examples, the whole tab 312 may be in an isosceles trapezoid shape, so that the whole tab 312 is in an axisymmetrical structure relative to the center thereof, which is beneficial to improving the stability of the whole tab 312, and the tab is not easily folded under the action of centrifugal force.

In some realizable ways, fig. 7 schematically shows a partial structure of a pole piece 31 of an embodiment. As shown in fig. 7 and 8, the tab 312 further includes an outward extending section 3122. The extension section 3122 is connected to the trapezoidal section 3121. The extension segment 3122 is located on a side of the trapezoidal segment 3121 away from the pole piece body 311. The extension section 3122 is connected to the straight side of the trapezoidal section 3121. The extension segment 3122 and the trapezoidal segment 3121 may be an integrally formed structure.

In some examples, the epitaxial segment 3122 is rectangular, e.g., the epitaxial segment 3122 can be rectangular or square. One straight side of the extension section 3122 is connected to the straight side of the trapezoidal section 3121. The epitaxial section 3122 is the design mode of rectangle, is convenient for use laser cutting technology to process and make whole utmost point ear 312, is favorable to reducing the processing degree of difficulty of utmost point ear 312.

Illustratively, the trapezoidal section 3121 may be an isosceles trapezoid. The included angle between one waist edge 3121a of the trapezoidal section 3121 and one straight edge of the corresponding outward extending section 3122 is P, wherein P is more than 90 ° and less than 180 °. For example, an included angle between one waist edge 3121a of the trapezoid section 3121 and one straight edge of the corresponding extending section 3122 is 100 °, 120 ° or 150 °, which is not limited in the embodiments of the present application.

Illustratively, fig. 9 schematically shows a partial structure of the pole piece 31 of an embodiment. Referring to fig. 9, the trapezoidal section 3121 may be a right trapezoid. The included angle between one waist edge 3121a of the trapezoidal section 3121 and one straight edge of the corresponding outward extending section 3122 is P, wherein P is more than 90 ° and less than 180 °. Along the width direction Y of the pole piece body 311, the other waist edge 3121a of the trapezoidal section 3121 is aligned with a corresponding straight edge of the extended section 3122, that is, an included angle between the other waist edge 3121a of the trapezoidal section 3121 and the corresponding straight edge of the extended section 3122 is 180 °, so that the edge of the tab 312 is a straight edge.

In some examples, the ratio of the dimension of the extended section 3122 to the dimension of the trapezoidal section 3121 along the width direction Y of the pole piece body 311 ranges from 0.3 to 1. Illustratively, the ratio of the size of the extension segment 3122 to the size of the trapezoidal segment 3121 is 1.

In this embodiment, fig. 10 schematically shows a connection structure of a battery cell 30 and an adapter component 50 according to an embodiment. Referring to fig. 10, the finished battery cell 30 may be electrically connected to the electrode terminal 40 or the adapter member 50 through the extending section 3122. The width of the trapezoidal section 3121 is greater than the width of the extended section 3122, so that the tab 312 is narrowed continuously at the extended section 3122. It should be noted that the width of the trapezoidal section 3121 and the width of the extending section 3122 may be the dimension measured along the length direction X of the pole piece body 311.

In some implementations, the ratio of the width D1 of bottom edge 312a to the width D2 of top edge 312b is K, where 1 < K ≦ 10. If the ratio K of the width D1 of the bottom edge 312a to the width D2 of the top edge 312b is greater than 10, on the one hand, the width D1 of the bottom edge 312a of the tab 312 is too large, and in the completely wound battery cell 30, the bottom edges 312a of the tabs 312 in the two tab groups 30a contact with each other, so that the battery cell 30 may be short-circuited; on the other hand, the tab 312 is too flat in the width direction Y of the pole piece body 311, the tab 312 has a small extension size along the width direction Y of the pole piece body 311, and there is a possibility that the formed tab group 30a and the electrode terminal 40 or the formed tab group 30a and the adaptor part 50 are difficult to weld, so that it is inconvenient to weld the tab group 30a and the electrode terminal 40 or the tab group 30a and the adaptor part 50.

In some realizable ways, fig. 11 schematically shows a partial structure of a pole piece 31 of an embodiment. As shown in fig. 11, the tab 312 has the reinforcing ribs 3123, so that the overall rigidity and flexibility of the tab 312 can be effectively improved, the deformation resistance of the tab 312 is improved, the possibility of the tab 312 shaking or swinging during the winding process is reduced, and the possibility of the tab 312 folding under the centrifugal action during the winding process to form the battery cell 30 is also reduced.

In some examples, the stiffener 3123 may be bar shaped. A plurality of reinforcing ribs 3123 can be designed on the tab 312. The plurality of reinforcing ribs 3123 of the tab 312 are spaced apart from each other. Illustratively, a plurality of reinforcing ribs 3123 are provided at intervals along the length direction X of the pole piece body 311. Alternatively, the rib 3123 is disposed obliquely with respect to the edge 311a of the pole piece body 311, that is, the rib 3123 forms an included angle with the edge 311a of the pole piece body 311.

In other examples, fig. 12 schematically shows a partial structure of pole piece 31 of another embodiment. Referring to fig. 12, the ribs 3123 may be in a grid shape. The whole tab 312 is covered with the reinforcing ribs 3123, so that the whole deformation resistance of the tab 312 can be improved, and the tab 312 is not easily folded.

In some examples, one side surface of the tab 312 is a plane in the thickness direction of the tab 312, and the other side is provided with the reinforcing ribs 3123. The stiffener 3123 may be a raised rib. In other examples, one side surface of the tab 312 has dimples and the other side forms a ridge, which forms the rib 3123. Illustratively, the tab 312 may be roll-processed by a correspondingly shaped press roll, so that dents are formed on one side surface of the tab 312 and bulges are simultaneously formed on the other side corresponding region.

The width direction Y of the pole piece body 311, the length direction X of the pole piece body 311, and the thickness direction of the tab 312 are perpendicular to each other.

In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, a fixed connection, an indirect connection via an intermediary, a connection between two elements, or an interaction between two elements. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

Reference throughout this specification to apparatus or components, in embodiments or applications, means or components must be constructed and operated in a particular orientation and therefore should not be construed as limiting the present embodiments. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically stated otherwise.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the embodiments of the application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein.

Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The term "plurality" herein means two or more. The term "and/or" herein is merely an association describing an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship; in the formula, the character "/" indicates that the preceding and following related objects are in a relationship of "division".

It is to be understood that the various numerical references referred to in the embodiments of the present application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of the present application.

It should be understood that, in the embodiment of the present application, the sequence numbers of the above-mentioned processes do not imply an order of execution, and the order of execution of the processes should be determined by their functions and inherent logic, and should not limit the implementation process of the embodiment of the present application in any way.

Claims

1. A pole piece, comprising:

a pole piece body;

utmost point ear, with the pole piece body links to each other, utmost point ear has base and topside, the base with the pole piece body links to each other, the width on base is greater than the width on topside, the at least part of utmost point ear is trapezoidal section, trapezoidal section with the pole piece body links to each other, utmost point ear still includes the section of extending, the section of extending with trapezoidal section links to each other, the width of trapezoidal section is greater than the width of the section of extending, the section of extending is the rectangle.

2. The pole piece of claim 1 wherein the tab has a decreasing width in a direction away from the body of the pole piece.

3. The pole piece according to claim 2, wherein of the two waist edges of the trapezoidal section, the included angle between the waist edge and the bottom edge is S, and at least one included angle S has a value in the range of 45 ° < S < 90 °.

4. The pole piece of claim 3 wherein the trapezoidal section is a right angle trapezoid or an isosceles trapezoid.

5. The pole piece of claim 1, wherein the ratio of the width of the bottom edge to the width of the top edge is K, wherein K is greater than 1 and less than or equal to 10.

6. The pole piece of claim 1 wherein the tab has a reinforcing rib.

7. A battery cell, characterized in that it comprises a pole piece according to any one of claims 1 to 6.