CN218731179U

CN218731179U - Battery core and battery monomer

Info

Publication number: CN218731179U
Application number: CN202222897015.5U
Authority: CN
Inventors: 邵雨薇; 苑丁丁; 车丽媛
Original assignee: Hubei Eve Power Co Ltd
Current assignee: Hubei Eve Power Co Ltd
Priority date: 2022-11-01
Filing date: 2022-11-01
Publication date: 2023-03-24
Anticipated expiration: 2032-11-01

Abstract

The utility model discloses an electricity core and battery monomer belongs to electric core and makes technical field. The battery cell comprises an electrode assembly, wherein the electrode assembly comprises a first pole piece and two layers of isolating films, the first pole piece is arranged between the two layers of isolating films, the electrode assembly is wound in a flat mode, and the electrode assembly on each layer is divided into a flat area and bending areas located on two opposite sides of the flat area; the second pole piece is arranged between the flat areas of the electrode assemblies on two adjacent layers, and the polarities of the first pole piece and the second pole piece are opposite. This implement neotype electric core has coiling concurrently and adds lamination integrated configuration, has reduced the manufacturing degree of difficulty of electric core, has improved the production efficiency and the goodness that electric core made, has still improved the energy density and the capacity density of electric core.

Description

Battery core and battery monomer

Technical Field

The utility model relates to an electricity core makes technical field, especially relates to an electricity core and battery monomer.

Background

With the wide application of lithium batteries in the fields of mobile phones, digital products, notebook computers, unmanned aerial vehicles, aeromodelling, electric tools, military industry, new energy vehicles, portable energy storage, medical equipment and the like, the domestic lithium ion battery industry has been rapidly developed. As an important part of lithium ion battery manufacturing, lamination and winding processes are receiving wide attention from academia and business industries.

The battery core manufacturing mode can be divided into a laminated mode and a winding mode. The lamination mode is that the positive and negative pole pieces and the diaphragm are cut into the size of the specified size, and then the positive pole piece, the diaphragm and the negative pole piece are laminated into the battery cell; the winding type is a process mode that the split pole piece is fixed on a winding needle and rotates along with the winding needle to roll the positive pole piece, the negative pole piece and the diaphragm into the battery cell.

The winding type battery cell is simple and convenient to operate, and can be rapidly completed in a semi-automatic or full-automatic mode. The laminated process has higher complexity, time and labor are wasted in manual operation, and industrialization is difficult due to equipment problems. In addition, in the aspect of quality control of the battery core, the winding type is easier to control, and the laminated type is more difficult to achieve good consistency due to complicated process steps.

Therefore, it is desirable to provide a battery cell and a battery cell to solve the above problems.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an electricity core and battery monomer compromise the advantage of coiling formula electricity core and lamination formula electricity core, not only easily make and energy density is high.

In order to realize the purpose, the following technical scheme is provided:

an electrical core, comprising:

the electrode assembly comprises a first pole piece and two layers of isolating films, wherein the first pole piece is arranged between the two layers of isolating films, the electrode assembly is wound in a flat mode, and the electrode assembly on each layer is divided into a flat area and bending areas located on two opposite sides of the flat area;

the second pole piece is arranged between the flat areas of the two adjacent layers of the electrode assemblies, and the polarities of the first pole piece and the second pole piece are opposite.

As an alternative of the battery cell, a plurality of hollow structures are arranged on the first pole piece along the length direction of the first pole piece at intervals, and the hollow structures are located in a bending area of the first pole piece.

As an alternative of the battery cell, the hollow structure is in a strip shape, and the extending direction of the strip-shaped hollow structure is perpendicular to the length direction of the first pole piece.

As an alternative to the battery cell, the length of the second pole piece is not greater than the length of the first pole piece in the flat area.

As an alternative of the battery cell, the first pole piece is a positive pole piece, and the total lengths of the two layers of the isolation films are the same.

As an alternative of the battery cell, the first pole piece is a negative pole piece, and the total lengths of the two layers of the isolating films are different.

As an alternative to the cell, the electrode assembly is wound in a zigzag or zigzag pattern.

As an alternative of the battery cell, the battery cell further comprises a fixing adhesive tape, the head ends of the two layers of the isolating films are located inside the battery cell, and the tail ends of the two layers of the isolating films or the tail ends of one of the two layers of the isolating films are bonded to the outer wall surface of the battery cell through the fixing adhesive tape.

A battery cell comprises the battery core.

As an alternative of the battery monomer, the battery further comprises a battery shell, and the battery core is packaged in the battery shell.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model provides an electric core, the whole flat type of electrode subassembly of electric core is folded and is wound, make every layer of electrode subassembly equally divide for the flat area and be located the district of bending at the relative both ends of flat area, wherein electrode subassembly's first pole piece is folded in advance and is pressed the setting between two-layer barrier film, the polarity of first pole piece is opposite with the polarity of second pole piece, it sets up between adjacent two-layer electrode subassembly's flat area about to fold the second pole piece, make electric core have concurrently and convolute and fold piece integrated configuration, the manufacturing degree of difficulty of electric core has been reduced, the production efficiency and the goodness that electric core was made have been improved, the energy density and the capacity density of electric core have still been improved.

The utility model provides a battery monomer makes electric core have concurrently to convolute and adds lamination integrated configuration, has reduced the manufacturing degree of difficulty of electric core, has improved the production efficiency and the excellent rate that electric core made, has still improved the energy density and the capacity density of electric core.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required to be used in the description of the embodiments of the present invention will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the contents of the embodiments of the present invention and the drawings without creative efforts.

FIG. 1 is a schematic view of an embodiment of the present invention in which the electrode assembly is not wound;

fig. 2 is a schematic structural diagram of a first pole piece in an embodiment of the present invention;

fig. 3 is a schematic structural view of the zigzag winding in the cell flat winding manner according to the embodiment of the present invention;

FIG. 4 is a schematic diagram of a first bonding method for the electrode assembly of an embodiment of the present invention;

FIG. 5 is a schematic diagram of a second bonding method for the electrode assembly of an embodiment of the present invention;

FIG. 6 is a schematic diagram of a third bonding method for the electrode assembly of an embodiment of the present invention;

fig. 7 is a schematic view of an electrode assembly according to an embodiment of the present invention.

Reference numerals are as follows:

100. an electric core;

1. an electrode assembly; 2. a second pole piece; 3. fixing the adhesive tape;

11. a first pole piece; 12. an isolation film; 13. a hollow structure; 14. a flat area; 15. a bending region.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description of the present invention and simplification of description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another, and are not to be construed as indicating or implying relative importance. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; either mechanically or electrically. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. "beneath," "under" and "beneath" a first feature includes the first feature being directly beneath and obliquely beneath the second feature, or simply indicating that the first feature is at a lesser elevation than the second feature.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

The winding type battery cell is simple and convenient to operate, and can be rapidly completed in a semi-automatic or full-automatic mode. The laminated process has higher complexity, time and labor are wasted in manual operation, and industrialization is difficult due to equipment problems. In addition, in the aspect of quality control of the battery core, the winding type is easier to control, and the laminated type is more difficult to achieve good consistency due to complicated process steps. The lithium ion battery has the advantages that the lithium ion battery is easy to manufacture, but the energy density is low, and the bent part is easy to lose efficacy; the laminate has advantages in that the capacity density and energy density of the battery are high, but the final quality of the battery is difficult to be secured.

In order to take advantages of both the winding type battery cell and the laminated battery cell into consideration, and to provide the battery cell and the battery cell with easy manufacturing and high energy density, the following detailed description of the embodiment is described in detail with reference to fig. 1 to 7. As shown in fig. 1 and fig. 3, the X direction is the length direction of the first pole piece, and the Y direction is the width direction of the first pole piece; the Z direction is the thickness direction of the whole battery cell after winding.

As shown in fig. 1 to 4, the battery cell 100 in this embodiment includes an electrode assembly 1 and a plurality of second pole pieces 2. As shown in fig. 1, the electrode assembly 1 includes a first pole piece 11 and two layers of isolation films 12, the first pole piece 11 is disposed between the two layers of isolation films 12, the electrode assembly 1 is wound in a flat manner, and each layer of the electrode assembly 1 is divided into a flat area 14 and a bending area 15 located at two opposite sides of the flat area 14. The second pole piece 2 is arranged between the flat areas 14 of the two adjacent electrode assemblies 1. The polarities of the first pole piece 11 and the second pole piece 2 are opposite, and when the first pole piece 11 is a positive pole piece, the second pole piece 2 is a negative pole piece; when the first pole piece 11 is a negative pole piece, the second pole piece 2 is a positive pole piece.

Further, the electrode assembly 1 is wound in a zigzag shape. As shown in fig. 3, 4, 5, 6 and 7, the way of the flat type of winding of the electrode assembly 1 in the present embodiment includes a zigzag winding and a loop winding.

It is understood that one, two or three second pole pieces 2 may be disposed between the flat regions 14 of the two adjacent electrode assemblies 1 according to actual use conditions, and the number is not limited herein.

In short, the utility model provides a battery cell 100, the whole flat formula of electrode subassembly 1 of battery cell 100 is lapped, make every layer of electrode subassembly 1 equally divide for flat district 14 and be located the bending area 15 at the 14 relative both ends in flat district, wherein the first pole piece 11 of electrode subassembly 1 is folded in advance and is pressed the setting between two-layer barrier film 12, the polarity of first pole piece 11 is opposite with the polarity of second pole piece 2, fold second pole piece 2 and press the setting between adjacent two-layer electrode subassembly 1's flat district 14 from top to bottom, make battery cell 100 have the coiling simultaneously and add lamination integrated configuration, the manufacturing difficulty of battery cell 100 has been reduced, the production efficiency and the goodness that battery cell 100 made have been improved, the energy density and the capacity density of battery cell 100 have still been improved.

Further, as shown in fig. 3, a plurality of hollow structures 13 are disposed at intervals along the length direction (X direction) of the bending region 15 of the first pole piece 11. Through setting up a plurality of hollow out construction 13 in the district 15 of bending at first pole piece 11, can reduce first pole piece 11 and distinguish 15 bending stress at the bending, prevent to bend and excessively lead to the positive pole active material layer on first pole piece 11 to drop, avoid first pole piece 11 circumstances such as fracture.

Illustratively, the hollow structures 13 are in the shape of a long strip, and the extending direction (Y direction) of the long strip-shaped hollow structures 13 is perpendicular to the length direction (X direction) of the first pole piece 11.

In other embodiments, the hollow structures 13 may also be circular or square.

Further, the length of the second pole piece 2 is not greater than the length of the first pole piece 11 in the flat area 14. By ensuring that the second pole piece 2 is in a non-curved flattened state, it helps to reduce the risk of ion extraction.

Further, the first pole piece 11 is a positive pole piece, and the positive pole piece includes a positive current collector and a positive active material layer coated on the surface of the positive current collector.

Further, the first electrode plate 11 may also be a negative electrode plate, and the negative electrode plate includes a negative electrode current collector and a negative electrode active material layer coated on the surface of the negative electrode current collector.

Further, the isolation film 12 includes a base layer and at least one functional layer coated on one side of the base layer. Specifically, the functional layer may be a mixture of ceramics, boehmite, or the like and a binder.

Further, the battery cell 100 further includes a fixing tape 3, the head ends of the two layers of isolation films 12 are located inside the battery cell 100, and the tail ends of the two layers of isolation films 12 or the tail ends of one of the two layers of isolation films 12 are bonded to the outer wall surface of the battery cell 100 through the fixing tape 3. The tail end of the isolating film 12 is bonded on the outer wall surface of the battery cell 100 through the fixing adhesive tape 3, so that the battery cell 100 is integrally formed.

Further, in the present embodiment, the total lengths of the two separators 12 are the same. Illustratively, as shown in fig. 4, the two layers of release films 12 have the same total length, and the excess part of the outermost circle of the two layers of release films 12 is bonded and shaped by the fixing tape 3. .

Further, in the present embodiment, the total lengths of the two layers of the separation film 12 are different. Illustratively, as shown in fig. 5, two layers of separation films 12 have different total lengths, one layer of separation film 12 is bonded and shaped on the upper portion of the battery cell 100 by using the fixing tape 3, and the other layer of separation film 12 is bonded and shaped on the lower portion of the battery cell 100 by using the fixing tape 3. As shown in FIG. 6, the two layers of isolation films 12 have different total lengths, the longer isolation film 12 is positioned at the outermost circle and is bonded and shaped by the fixing tape 3. As shown in fig. 7, the total lengths of the two isolation films 12 are different, the electrode assembly is wound in a zigzag manner, the lengths of the two isolation films 12 are different, the longer isolation film 12 is positioned at the outermost circle, and the longer isolation film 12 is bonded and shaped by the fixing adhesive tape 3.

The embodiment further provides a single battery, which includes the above-mentioned battery cell 100, and has a winding and laminating combined structure, so that the difficulty in manufacturing the battery cell 100 is reduced, and the single battery has high energy density, and high production efficiency and high yield.

Further, the battery cell further includes a battery case, and the battery cell 100 is packaged in the battery case. The battery can is made of metal or plastic, for example, and not limited to this.

It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.

Claims

1. Electric core, its characterized in that includes:

the electrode assembly (1) comprises a first pole piece (11) and two layers of isolation films (12), wherein the first pole piece (11) is arranged between the two layers of isolation films (12), the electrode assembly (1) is wound in a flat mode, and the electrode assembly (1) of each layer is divided into a flat area (14) and bending areas (15) located on two opposite sides of the flat area (14);

the second pole piece (2) is arranged between the flat areas (14) of the two adjacent layers of the electrode assembly (1), and the polarities of the first pole piece (11) and the second pole piece (2) are opposite.

2. The battery cell of claim 1, wherein the first pole piece (11) is provided with a plurality of hollow structures (13) at intervals along a length direction thereof, and the hollow structures (13) are located in a bending region (15) of the first pole piece (11).

3. The battery cell of claim 2, wherein the hollow structure (13) is in the shape of a long strip, and the extending direction of the long strip-shaped hollow structure (13) is perpendicular to the length direction of the first pole piece (11).

4. The cell of claim 1, wherein the length of the second pole piece (2) is not greater than the length of the first pole piece (11) at the flattened area (14).

5. The cell of any of claims 1 to 4, wherein the total length of the two layers of separator film (12) is the same.

6. The cell of any of claims 1 to 4, wherein the two layers of the separator film (12) differ in overall length.

7. The cell of any of claims 1 to 4, wherein the electrode assembly (1) is wound in a zigzag or zigzag pattern.

8. The battery cell of any one of claims 1 to 4, further comprising a fixing tape (3), wherein the head ends of the two layers of the separation films (12) are located inside the battery cell (100), and the tail end of the separation film (12) of one or both layers of the separation films (12) is adhered to the outer wall surface of the battery cell (100) through the fixing tape (3).

9. Battery cell, characterized in that it comprises a battery cell (100) according to any of claims 1 to 8.

10. The battery cell of claim 9, further comprising a battery case, wherein the battery cell (100) is encapsulated in the battery case.