CN213692110U

CN213692110U - Electrode assembly and battery

Info

Publication number: CN213692110U
Application number: CN202023116334.5U
Authority: CN
Inventors: 邓干群
Original assignee: Ningde Amperex Technology Ltd
Current assignee: Ningde Amperex Technology Ltd
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2021-07-13
Anticipated expiration: 2030-12-22

Abstract

An electrode assembly includes a first pole piece and a second pole piece arranged in a winding manner, wherein the first pole piece comprises a first current collector and a first active material layer; the winding of first pole piece ends the end and is located electrode assembly's surface, the winding of first mass flow body ends the end and is equipped with first empty paper tinsel district, and electrode assembly still includes first utmost point ear and second utmost point ear, and first utmost point ear electricity is connected in first empty paper tinsel district, and first utmost point ear sets up along the first direction, and second utmost point ear electricity is connected the second pole piece, and the second utmost point ear sets up along the second direction, and the contained angle between first direction and the second direction is less than or equal to 90 degrees. According to the electrode assembly, the first tab is connected to the first empty foil area on the outer surface of the electrode assembly, the connection structure between the tab and the pole piece is simplified, the manufacturing difficulty is reduced, and meanwhile, the first tab and the second tab are respectively arranged in different directions, so that the size design of the electrode assembly is not limited by the arrangement positions of the tabs. The present application also provides a battery having the above electrode assembly.

Description

Electrode assembly and battery

Technical Field

The present invention relates to the field of electrochemical devices, and more particularly, to an electrode assembly and a battery having the same.

Background

With the continuous development of modern society, lithium ion batteries are more and more widely applied to mobile devices such as mobile phones, smart watches, smart bracelets, bluetooth headsets, notebook computers, even electric bicycles, electric motorcycles, electric automobiles and the like due to the advantages of high energy density, no environmental pollution and the like.

Electronic products such as intelligent watches, intelligent bracelets, Bluetooth earphones and the like are convenient to carry about due to small size, are widely sought and purchased for use by the public, and are miniaturized or even miniaturized lithium ion batteries corresponding to built-in lithium ion batteries. Among the prior art, the positive and negative pole ear of electricity core sets up along same direction usually to connect inside electric core, lead to the size of a certain direction of electricity core to need to satisfy the installation requirement of positive and negative pole ear simultaneously, and make the degree of difficulty big, make the miniaturized development of battery size receive the restriction.

SUMMERY OF THE UTILITY MODEL

In view of the above situation, the present application provides an electrode assembly and a battery having the same, wherein the first tab is connected to the first empty foil area on the outer surface of the electrode assembly, so as to facilitate simplification of the connection structure between the tab and the pole piece and reduce the manufacturing difficulty, and meanwhile, the first tab and the second tab are respectively arranged in different directions of the electrode assembly, so that the size design of the electrode assembly is not limited by the arrangement position of the tab, and the battery size miniaturization development is facilitated.

Embodiments of the present application provide an electrode assembly including a first pole piece and a second pole piece arranged in a winding. The first pole piece comprises a first current collector and a first active material layer arranged on the surface of the first current collector. The winding end of the first pole piece is positioned on the outer surface of the electrode assembly along the winding direction of the first pole piece. The winding termination end of the first current collector is provided with a first empty foil area, and the surface of the first empty foil area is not provided with the first active material layer. The electrode assembly further includes a first tab and a second tab. The first tab is electrically connected to the first empty foil area and extends along a first direction. The second pole lug is electrically connected with the second pole piece and extends along a second direction, and an included angle between the first direction and the second direction is smaller than or equal to 90 degrees.

In some embodiments, the electrode assembly includes first and second side portions disposed opposite to each other and arranged in a length direction of the electrode assembly. The first tab is disposed at the first side portion. The first side is provided with a first cambered surface. The first tab portion is arranged along the first arc surface in a bending mode.

In some embodiments, the electrode assembly includes first and second planes disposed opposite to each other in a thickness direction of the electrode assembly. The winding termination end of the first pole piece is arranged on the first plane. The first tab comprises a straight portion, an arc portion and a bending portion which are connected in sequence. The straight portion is located on the first plane and connects the first empty foil zone. The arc-shaped part corresponds to the first arc surface, and the bending part extends out of the first side part.

In some embodiments, the end of the arc portion connected to the bending portion does not exceed the top edge of the first arc surface.

In some embodiments, the winding end of the first pole piece is located on the first arc surface, the first tab includes an arc portion and a bent portion, the arc portion fits the first arc surface and is connected to the first empty foil area, and the bent portion extends out from the first side portion.

In some embodiments, the winding termination end of the first pole piece does not extend beyond the top edge of the first arc surface in the first direction.

In some embodiments, the first tab is attached to an outer surface of the first empty foil zone.

In some embodiments, the second pole tab is connected to a side of the second pole piece along the second direction.

In some embodiments, the portions of the first and second tabs that extend out of the electrode assembly are provided with seals.

Embodiments of the present application further provide a battery, including a package bag and the electrode assembly of the above embodiments, the electrode assembly is accommodated in the package bag.

Above-mentioned electrode subassembly is favorable to simplifying the connection structure between utmost point ear and the pole piece through connecting first utmost point ear in the first empty paper tinsel district of electrode subassembly surface, reduces the manufacturing degree of difficulty, sets up first utmost point ear and second utmost point ear respectively in the equidirectional not simultaneously, makes electrode subassembly's size design not receive utmost point ear and sets up the restriction of position, is favorable to the miniaturized development of battery size.

Drawings

Fig. 1 is a schematic view showing the developed structure of a first pole piece and a second pole piece in an electrode assembly.

Fig. 2 is a schematic structural view of an electrode assembly in one embodiment.

Fig. 3 is a structural schematic view of the electrode assembly shown in fig. 2 in another direction.

Fig. 4 is a top view of the electrode assembly shown in fig. 2.

FIG. 5 is a schematic view of an electrode assembly in one embodiment.

Fig. 6 is a schematic view illustrating the structure of the electrode assembly of fig. 5 in another direction.

Fig. 7 is a top view of the electrode assembly shown in fig. 5.

Fig. 8 is a schematic diagram of a battery in one embodiment.

Description of the main element symbols:

the specific implementation mode is as follows:

the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. In the following embodiments, features of the embodiments may be combined with each other without conflict.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

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 application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "or/and" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1 and 2, in an embodiment, an electrode assembly 100 includes a first pole piece 10 and a second pole piece 20, and the first pole piece 10 and the second pole piece 20 are wound.

The electrode assembly 100 further includes a first tab 30 and a second tab 40. The electrode assembly 100 includes a first side portion 101 and a second side portion 102 that are disposed opposite to each other and arranged in a longitudinal direction, and the direction indicated by an arrow a in fig. 2 is the longitudinal direction of the electrode assembly 100. The first tab 30 is disposed at the first side 101 of the electrode assembly 100 along the first direction, and the first tab 30 is electrically connected to the first pole piece 10. The direction indicated by the arrow B in fig. 2 is the width direction of the electrode assembly 100. The length direction is perpendicular to the width direction. The electrode assembly 100 includes a first end 103 and a second end 104 that are oppositely disposed and arranged in a width direction, the second tab 40 is disposed at the first end 103 of the electrode assembly 100 in the second direction, and the second tab 40 is electrically connected to the second tab 20. An included angle between the first direction and the second direction is less than or equal to 90 degrees. In the present embodiment, the first direction is a direction indicated by an arrow a, the second direction is a direction indicated by an arrow B, and the central axes of the first tab 30 and the second tab 40 are substantially perpendicular to each other.

In the present application, with electrode assembly 100 first utmost point ear 30 with second utmost point ear 40 sets up respectively in the equidirectional, and it is limited to have avoided it to place the size that leads to the fact in same direction, has both been favorable to the miniaturized development of battery size, is favorable to again solving the problem that the position is difficult is placed to utmost point ear in the small-size battery.

With continued reference to fig. 3 and 4, the winding end of the first pole piece 10 is located on the outer surface of the electrode assembly 100, and the first tab 30 is connected to the winding end of the first pole piece 10. Specifically, the first pole piece 10 includes a first current collector 11 and a first active material layer 12 disposed on a surface of the first current collector 11. Along the winding direction of the first electrode sheet 10, a first empty foil area 111 is disposed at the winding termination end of the first current collector 11, the first active material layer 12 is not disposed on the surface of the first empty foil area 111, the first empty foil area 111 is located on the outer surface of the electrode assembly 100, and the first tab 30 is electrically connected to the first empty foil area 111. The electrical connection mode includes but is not limited to welding, conductive adhesive bonding, etc., the arrangement of the empty foil area is favorable for the operation of electrical connection, reduces the influence of the active material layer on the connection strength, and in addition, the first tab 30 is directly connected with the first empty foil area 111 on the outer surface of the electrode assembly 100, which is favorable for simplifying the connection structure between the tab and the pole piece and reducing the manufacturing difficulty. The first tab 30 may be bent according to actual product requirements, and the first tab 30 may be bent upward or downward or may be bent at multiple angles in the view angle of fig. 4.

Further, the first side portion 101 of the electrode assembly 100 is provided with a first arc surface, the winding termination end of the first pole piece 10 is located on the first arc surface, the first tab 30 includes an arc portion 31 and a bent portion 32, the arc portion 31 is attached to the first arc surface and is electrically connected to the outer surface of the first empty foil region 111, and the bent portion 32 extends out from the first side portion 101. In the first direction, the winding end of the first pole piece 10 does not exceed the top edge of the first arc surface, and the end of the arc portion 31 connected to the bent portion 32 does not exceed the top edge of the first arc surface, so as to reduce the variation in the width and thickness of the electrode assembly 100 caused by connecting the first tab 30 to the winding end of the first pole piece 10.

Referring to fig. 5, 6 and 7, in another embodiment, the electrode assembly 100 is substantially the same as the previous embodiment except that the electrode assembly 100 includes a first plane 105 and a second plane 106 opposite to each other along the stacking direction of the first pole piece 10 and the second pole piece 20, i.e., the thickness direction of the electrode assembly 100, the winding end of the first pole piece 10 is disposed on the first plane 105, and the first pole tab 30 is partially disposed on the first plane 105 and electrically connected to the winding end of the first pole piece 10. Specifically, first utmost point ear 30 is including the straight portion 33, the arc portion 31 and the portion 32 of bending that connect gradually, straight portion 33 is located first plane 105 and connect in the surface in first empty foil district 111 is existing to be favorable to welding first utmost point ear 30 and first pole piece 10, can enlarge the connection scope of first utmost point ear 30 and first pole piece 10 again, improves joint strength. The arc portion 31 is attached to the first arc surface, one end of the arc portion 31 connected with the bending portion 32 does not exceed the top edge of the first arc surface, and the bending portion 32 extends out of the first side portion 101.

Referring to fig. 1 and fig. 2 again, in the second direction, the second tab 40 is connected to one side of the second pole piece 20 and is close to the winding start end of the second pole piece 20. After the second pole piece 20 is stacked and wound with the first pole piece 10, the second pole piece 40 protrudes from the middle layer of the jelly roll to the first end 103 of the electrode assembly 100, so as to equalize the charge and discharge rates of the electrode assembly 100. It is understood that in other embodiments, the second tab 40 may be attached to any position on the side of the second tab 20, such that any layer of the core of the second tab 40 extends, and the application is not limited thereto.

Referring to fig. 8, an embodiment of the present application further provides a battery 200, which includes a packaging bag 201 and the electrode assembly 100 in the above embodiment, the electrode assembly 100 is accommodated in the packaging bag 201, and the first tab 30 and the second tab 40 of the electrode assembly 100 extend out of the packaging bag 201. The first tab 30 and the second tab 40 extend out of the electrode assembly 100, and a sealing member 50 is further disposed on the portion of the electrode assembly 100, where the sealing member 50 is fixed to the connection portion of the first tab 30 and the second tab 40 with the packaging bag 201, so as to prevent the electrolyte from seeping out.

Although the present application has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the present application.

Claims

1. An electrode assembly, comprising:

the first pole piece comprises a first current collector and a first active material layer arranged on the surface of the first current collector; and

the first pole piece and the second pole piece are wound;

its characterized in that follows the direction of winding of first pole piece, the end that terminates of the coiling of first pole piece is located electrode assembly's surface, the end that terminates of the coiling of the first mass flow body is equipped with first empty foil district, first empty foil district surface does not set up first active material layer, electrode assembly still includes first utmost point ear and second utmost point ear, first utmost point ear electricity connect in first empty foil district, and extend along first direction, second utmost point ear electricity is connected the second pole piece, and extend along the second direction, first direction with contained angle between the second direction is less than or equal to 90 degrees.

2. The electrode assembly according to claim 1, wherein the electrode assembly includes a first side portion and a second side portion which are oppositely disposed and arranged along a length direction of the electrode assembly, the first tab is disposed at the first side portion, the first side portion is provided with a first arc surface, and the first tab portion is bent along the first arc surface.

3. The electrode assembly according to claim 2, wherein the electrode assembly includes a first plane and a second plane oppositely disposed in a thickness direction of the electrode assembly, the winding end of the first pole piece is disposed at the first plane, the first tab includes a straight portion, an arc portion, and a bent portion sequentially connected, the straight portion being disposed at the first plane and connecting the first empty foil zone, the arc portion corresponding to the first arc surface, and the bent portion protruding from the first side portion.

4. The electrode assembly of claim 3, wherein the end of the arc-shaped part connecting the bent part does not exceed the top edge of the first arc-shaped surface.

5. The electrode assembly of claim 2, wherein the winding end of the first pole piece is located at the first arc surface, the first tab includes an arc portion and a bent portion, the arc portion conforms to the first arc surface and connects to the first empty foil region, and the bent portion extends from the first side portion.

6. The electrode assembly of claim 5, wherein, in the first direction, the winding termination of the first pole piece does not extend beyond the top edge of the first arc.

7. The electrode assembly of claim 1 wherein said first tab is attached to an outer surface of said first hollow foil region.

8. The electrode assembly of claim 1, wherein the second pole tab is connected to a side of the second pole piece along the second direction.

9. The electrode assembly of claim 1 wherein the portions of the first and second tabs that extend out of the electrode assembly are provided with seals.

10. A battery comprising a package pouch and the electrode assembly of any one of claims 1-9, said electrode assembly being contained in said package pouch.