CN212542528U

CN212542528U - Battery roll core and battery

Info

Publication number: CN212542528U
Application number: CN202021649563.0U
Authority: CN
Inventors: 余正发; 彭冲; 胡典洋; 李俊义; 徐延铭
Original assignee: Zhuhai Cosmx Battery Co Ltd
Current assignee: Zhuhai Cosmx Battery Co Ltd
Priority date: 2020-08-10
Filing date: 2020-08-10
Publication date: 2021-02-12
Anticipated expiration: 2030-08-10

Abstract

The utility model provides a battery roll core and a battery, which comprises a diaphragm, a first pole piece and two second pole pieces, wherein the first pole piece is positioned between the two second pole pieces, and the polarities of the first pole piece and the second pole piece are opposite; diaphragms are arranged between the first pole piece and the second pole piece; the first pole piece comprises a first pole lug, a first current collector and a first active material layer, and the first active material layer is symmetrically coated on two surfaces of the first current collector; the second pole piece comprises a second pole lug, a second current collector and a second active material layer, wherein the second active material layer is coated on the first surface of the second current collector, and the first surface and the first pole piece are oppositely arranged. The embodiment of the utility model provides a promote the quick performance of filling of battery.

Description

Battery roll core and battery

Technical Field

The utility model relates to a battery technology field especially relates to a battery rolls up core and battery.

Background

With the popularization of consumer electronics products such as smart phones and notebook computers, the related technologies have also been developed rapidly, and the development of lithium ion batteries as energy storage elements used in consumer electronics products has also met with great market opportunities. With the increasing requirements of people on the charging speed of consumer electronic products, consumer electronic product manufacturers also have increasing requirements on the quick charging performance of lithium ion batteries.

In the prior art, the active material layers of the positive plate and the negative plate in the battery roll core need to be arranged oppositely, so that lithium ions in the positive active material layer can move to the negative active material layer, and the function of the active material is exerted. Because the positive plate and the negative plate need to be bent by the battery roll core, if the active material coatings of the two surfaces of the bent positive plate or the bent negative plate are kept to be oppositely arranged, the active material coatings cannot interact with the electrode plates with opposite polarities, so that the active material coatings of the two surfaces of the positive plate or the negative plate are usually required to be ensured to be not oppositely arranged by the bending parts, and the thickness of the battery roll core is reduced under the condition of ensuring the battery capacity. Therefore, the current collector of the positive electrode sheet or the negative electrode sheet has a region coated on only one side, and the region coated on one side is a bent portion. The current density of the single-sided paste coating area of the pole piece is higher than that of the paste coating area of the double-sided area in the charging process of the battery due to the mode, and lithium is more easily separated in the single-sided area of the pole piece during high-current charging, so that the quick charging performance of the battery is limited. It can be seen that the prior art batteries have poor rapid charging performance.

SUMMERY OF THE UTILITY MODEL

An embodiment of the utility model provides a battery rolls up core and battery to the quick charge performance of battery among the solution prior art is relatively poor.

In a first aspect, an embodiment of the present invention provides a battery roll core, including a diaphragm, a first pole piece and two second pole pieces, where the first pole piece is located between the two second pole pieces, and the polarities of the first pole piece and the second pole piece are opposite;

diaphragms are arranged between the first pole piece and the second pole piece;

the first pole piece comprises a first pole lug, a first current collector and a first active material layer, and the first active material layer is symmetrically coated on two surfaces of the first current collector;

the second pole piece comprises a second pole lug, a second current collector and a second active material layer, wherein the second active material layer is coated on the first surface of the second current collector, and the first surface and the first pole piece are oppositely arranged.

Optionally, the first pole piece is a negative pole piece, and the second pole piece is a positive pole piece.

Optionally, the first active material layer is disposed opposite to the second active material layer.

Optionally, the first tab is located on the first current collector in a region not coated with the first active material layer.

Optionally, the second pole ears of the two second pole pieces are electrically connected, so that the two second pole pieces are electrically connected in parallel.

Optionally, the separator, the first pole piece and the two second pole pieces are wound to form the battery roll core.

Optionally, the second pole lug of the second pole piece is disposed at the first end of the second pole piece, and the diaphragm and the first pole piece are not disposed between the first ends of the two second pole pieces; the first end is located on an inner layer of the battery roll core.

Optionally, the second end of the second pole piece is not coated with the first active material layer; the second end portion is located on the outer layer of the battery roll core.

In a second aspect, the embodiment of the present invention further provides a battery, which includes a battery case, an electrolyte and the battery roll core as described in any of the above embodiments.

The embodiment of the utility model provides a set up the first pole piece in rolling up the core with the battery between two second pole pieces, at this moment, the active material layer of first pole piece both sides is relative with the active material layer of two second pole pieces respectively, the first utmost point active material layer of the both sides of first pole piece all can obtain make full use of, and can the symmetric distribution in the both sides of first utmost point fluid collection, thereby can be unanimous at the two-sided electric current surface density of scribbling the cream flow of battery charging in-process first pole piece, the difficult lithium of separating out of first pole piece, and then can promote the quick charging performance of battery.

Drawings

In order to more clearly illustrate the technical solutions of 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 introduced 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 these drawings without inventive labor.

Fig. 1 is a schematic structural diagram of a battery roll core provided by an embodiment of the present invention;

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

fig. 3 is a second schematic structural diagram of the first pole piece according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a second pole piece according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which the invention belongs. The use of "first," "second," and similar terms in the description herein do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. Also, the use of the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.

Referring to fig. 1 to 4, an embodiment of the present invention provides a battery roll core, including a separator 300, a first pole piece 100 and two second pole pieces 200, where the first pole piece 100 is located between the two second pole pieces 200, and the polarities of the first pole piece 100 and the second pole piece 200 are opposite;

a diaphragm 300 is arranged between the first pole piece 100 and the second pole piece 200;

the first pole piece 100 comprises a first current collector 101, a first active material layer 102 and a first tab 103, wherein the first active material layer 102 is symmetrically coated on two surfaces of the first current collector 101;

the second pole piece 200 includes a second current collector 201, a second active material layer 202, and a second pole ear 203, where the second active material layer 202 is coated on a first surface of the second current collector 201, and the first surface is disposed opposite to the first pole piece 100.

In the embodiment of the present invention, referring to fig. 1, the position relationship between the first pole piece 100 and the second pole piece 200 can be two pieces of the first pole piece 100 clamped by the second pole piece 200.

It should be understood that the polarities of the first and

second pole pieces

100 and 200 are opposite to each other, so that the interaction between the positive and negative poles can be realized.

Since the active material layers of the second pole piece 200 and the first pole piece 100 in the battery roll core need to be oppositely arranged. In this way, lithium ions in the positive electrode active material can move between the first active material layer 102 and the second active material layer 202, thereby functioning as an active material. In the bending region of the first pole piece 100, the two bent surfaces are respectively opposite to the two second pole pieces 200, and the condition that the two surfaces of the first pole piece 100 are directly opposite does not exist, at this time, the two surfaces of the first pole piece 100 are coated with the first active material, and the first active materials on the two surfaces can play a role.

For one first pole piece 100, the more active material that is generally able to function, the corresponding increase in battery capacity will occur. Referring to fig. 2 to 3 together, in order to increase the battery capacity, the first active material layer 102 may be coated on both sides of the first current collector 101, and the coating area may be the entire side surface of the first current collector 101 or may be a partial area of the side surface of the first current collector 101. In other words, the above-mentioned both side surfaces of the first current collector 101 may have empty foil regions, i.e., regions not coated with the active material layer, to facilitate the disposition of the tabs of the first pole piece 100.

In order to reduce the thickness of the battery roll core while ensuring the battery capacity, the second active material layer 202 may be coated on one side of the second current collector 201 and disposed opposite to the first active material layer 102, so that lithium ions may move between the first active material layer 102 and the second active material layer 202, thereby implementing the discharge process of the battery.

Meanwhile, in order to prevent the direct contact of the positive and negative electrode active materials, the safety performance of the battery is improved. A separator 300 may be disposed between each of the first and

second pole pieces

200 and 100.

Specifically, the separator 300 may include a substrate and a coating layer, wherein the substrate may be a Polyethylene (PE) single layer film, a polypropylene (PP) single layer film or a polypropylene-polyethylene-polypropylene three-layer composite film, and the coating layer may be at least one of porous silicon dioxide, aluminum oxide, titanium dioxide and zirconium dioxide.

The material of the first current collector 101 may be set according to actual needs. In the embodiment of the present invention, the first current collector 101 may be a copper foil. Meanwhile, the first active material layer 102 is composed of a first active material, and the type and proportion thereof may be set according to actual needs, and may generally include materials such as graphite, hard carbon, silicon, and silicon oxide, which are not further limited herein.

The second current collector may be an aluminum foil. The kind and ratio of the active material in the second active material layer 202 may be set according to actual needs, and may generally include LiCoO2, LiNiCoMnO2, LiCoAlO2, LiMn2O4, and the like, and is not limited thereto.

It should be understood that the materials of the first pole piece 100 and the second pole piece 200 can be interchanged, and the composition of the first active material layer 102 and the composition of the second active material layer 202 can be interchanged.

The connection mode of the first tab 103 and the first current collector 101 may be set according to actual needs. In the embodiment of the present invention, the first tab 103 may be fixed and electrically connected to the first current collector 101 by welding; in another embodiment, the first tab 103 may be bonded to the first current collector 101 by a tab glue, which is not further limited herein.

Similar to the first tab 103, in order to facilitate the disposition of the second tab 203, the second tab 203 may also be disposed in a region of the second current collector 201 that is not coated with the second active material.

The connection mode of the second current collector 201 and the second tab 203 can also be set according to actual needs, in the embodiment of the present invention, the connection mode can also be realized by welding or bonding.

The embodiment of the utility model provides a set up first pole piece 100 in rolling up the core with the battery between two second pole pieces 200, at this moment, the active material layer of first pole piece 100 both sides is relative with the active material layer of two second pole pieces 200 respectively, the first active material layer of the both sides of first pole piece 100 all can obtain make full use of, and can symmetric distribution in the both sides of first mass flow body, thereby can be in the battery charging process the current surface density that first pole piece 100 two-sided scribbles the cream and flow through unanimous, the difficult lithium of analyzing of first pole piece 100, and then can promote the quick charging performance of battery.

Optionally, the first pole piece 100 is a negative pole piece, and the second pole piece 200 is a positive pole piece.

In the embodiment of the present invention, when the first pole piece 100 is a negative pole piece, the second pole piece 200 can be a positive pole piece, which is equivalent to a positive pole piece disposed between two negative pole pieces. At this time, the first active material layer 102 and the second active material layer 202 may be maintained to be oppositely disposed.

Further, the first active material layer 102 and the second active material layer 202 may be disposed oppositely, so as to ensure that the first active material layer 102 and the second active material layer 202 can be fully utilized.

Further, as described above, both sides of the first current collector 101 may have empty foil regions, i.e., regions not coated with the active material layer, to facilitate the disposition of the first tab 103. In an embodiment of the present invention, the first tab 103 may be located on the first current collector 101 in a region where the first active material layer 102 is not coated, so as to reduce the influence of the first tab 103 on the chemical properties of the first active material layer 102. Of course, in other embodiments, the first tab may also be disposed on the first active material layer 102.

Optionally, the second tabs 203 of the two second pole pieces 200 are electrically connected, so that the two second pole pieces 200 are electrically connected in parallel.

The embodiment of the utility model provides a second utmost point ear 203 electricity through with two second pole pieces 200 is connected to make two second pole pieces 200 parallelly connected, the resistance after parallelly connected is less than the resistance of monolithic second pole piece 200, and then can reduce the internal resistance of battery.

Alternatively, the separator 300, the first pole piece 100 and the two second pole pieces 200 may be wound to form the battery core.

Further, in order to facilitate electrical connection between the two second pole pieces 200, the second tab of the second pole piece 200 may be disposed at a first end of the second pole piece 200, and the separator 300 and the first pole piece 100 are not disposed between the first ends of the two second pole pieces 200; the first end portion is located in an inner layer of the battery roll core.

Meanwhile, optionally, the first active material layer 102 is not coated on the second end of the second pole piece 200; the second end portion is located on an outer layer of the battery roll core.

It should be understood that the second pole piece 200 may be wound with the first end as a starting point, and the second end is located on the outer layer of the winding core after winding.

The embodiment of the utility model provides a still provide a battery, including battery case, electrolyte and as above arbitrary embodiment the battery roll core.

The above embodiments are only specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention, and all should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A battery roll core is characterized by comprising a diaphragm, a first pole piece and two second pole pieces, wherein the first pole piece is positioned between the two second pole pieces, and the polarities of the first pole piece and the second pole piece are opposite;

diaphragms are arranged between the first pole piece and the second pole piece;

2. The battery roll core of claim 1, wherein the first pole piece is a negative pole piece and the second pole piece is a positive pole piece.

3. The battery jellyroll of claim 1, wherein the first active material layer is disposed opposite the second active material layer.

4. The battery jellyroll of claim 1, wherein the first tab is located on the first current collector in an area not coated with the first active material layer.

5. The battery jellyroll of claim 1, wherein the second pole pieces of the second pole pieces are electrically connected such that the second pole pieces are electrically connected in parallel.

6. The battery jellyroll of claim 1, wherein the separator, first pole piece, and two second pole pieces are wound to form the battery jellyroll.

7. The battery jellyroll of claim 6, wherein the second pole piece ears are disposed at the first end of the second pole piece, and the separator and the first pole piece are not disposed between the first ends of the two second pole pieces; the first end is located on an inner layer of the battery roll core.

8. The battery jellyroll of claim 6, wherein the second end of the second pole piece is uncoated by the first active material layer; the second end portion is located on the outer layer of the battery roll core.

9. A battery comprising a battery can, electrolyte and a battery jelly roll according to any one of claims 1 to 8.