CN213878152U

CN213878152U - Electrode pole piece and lithium ion battery

Info

Publication number: CN213878152U
Application number: CN202022860964.7U
Authority: CN
Inventors: 阚光伟; 鲁俊文
Original assignee: Sunwoda Electric Vehicle Battery Co Ltd
Current assignee: Xinwangda Power Technology Co ltd
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2021-08-03
Anticipated expiration: 2030-12-02

Abstract

The application relates to an electrode plate and a lithium ion battery, and belongs to the technical field of batteries. An electrode pole piece comprises a current collector, an electrode layer and a dioctyl terephthalate layer, wherein the electrode layer is laminated on the current collector; a dioctyl terephthalate layer is laminated on the current collector and in contact with the electrode layer. The dioctyl terephthalate layer of the electrode pole piece is laminated on the current collector and is abutted with the electrode layer, when the electrode pole piece is in a high-temperature environment, the dioctyl terephthalate starts to decompose to generate gas, the explosion-proof valve is broken, the battery is prevented from being ignited, and the safety of the battery is higher.

Description

Electrode pole piece and lithium ion battery

Technical Field

The utility model relates to a battery technology field especially relates to an electrode plate and lithium ion battery.

Background

The lithium ion battery, as an energy battery which is developed at a high speed in recent years, has the advantages of high energy density, strong charge retention capacity, long cycle life, no memory effect and the like, is widely applied to the fields of mobile phones, computers, automobiles and the like at present, and needs to have safety performance while realizing high performance. However, the lithium ion battery is easy to cause the ignition of the electrolyte additive at high temperature, so that the safety of the lithium ion battery is low.

SUMMERY OF THE UTILITY MODEL

Accordingly, it is necessary to provide an electrode tab capable of improving the safety of a battery.

In addition, a lithium ion battery is also provided.

An electrode sheet comprising:

a current collector;

an electrode layer laminated on the current collector;

and a dioctyl terephthalate layer laminated on the current collector and in contact with the electrode layer.

The dioctyl terephthalate layer of the electrode pole piece is laminated on the current collector and is abutted with the electrode layer, when the electrode pole piece is in a high-temperature environment, the dioctyl terephthalate starts to decompose to generate gas, the explosion-proof valve is broken, the battery is prevented from being ignited, and the safety of the battery is higher.

In one embodiment, the number of the dioctyl terephthalate layers is two, and the two dioctyl terephthalate layers are respectively positioned on two sides of the electrode layer.

In one embodiment, the dioctyl terephthalate layer and the electrode layer are both in a strip shape, and the extension direction of the dioctyl terephthalate layer is the same as that of the electrode layer.

In one embodiment, the ratio of the width of the dioctyl terephthalate layer to the width of the electrode layer is 1: 500-3: 40.

In one embodiment, the width of the dioctyl terephthalate layer is 2mm to 6mm, and the width of the electrode layer is 80mm to 1000 mm.

In one embodiment, the dioctyl terephthalate layer has a thickness less than a thickness of the electrode layer.

In one embodiment, the ratio of the thickness of the dioctyl terephthalate layer to the thickness of the electrode layer is 2: 5-1: 1.

In one embodiment, the current collector further comprises a ceramic layer laminated between the dioctyl terephthalate layer and the current collector.

In one embodiment, the electrode plate is a positive electrode plate or a negative electrode plate.

A lithium ion battery comprises the electrode pole piece.

Drawings

FIG. 1 is a schematic structural diagram of an electrode pad according to an embodiment;

FIG. 2 is a schematic view of another angle structure of the electrode pad shown in FIG. 1;

fig. 3 is a schematic structural view of an electrode pad according to another embodiment.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

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. 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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Referring to fig. 1 and 2, an electrode tab 10 according to an embodiment includes a current collector 100, an electrode layer 200, and a dioctyl terephthalate layer 300.

The current collector 100 is selected from one of aluminum foil and copper foil. When the electrode tab 10 is a positive electrode tab, the current collector 100 is an aluminum foil. Further, the thickness of the current collector 100 is 9 to 16 μm.

When the electrode tab 10 is a negative electrode tab, the current collector 100 is a copper foil. Further, the thickness of the current collector 100 is 4 to 16 μm.

The electrode layer 200 is stacked on the current collector 100. Specifically, the thickness of the electrode layer 200 is 60 μm to 300 μm. Specifically, the width of the electrode layer 200 is 80mm to 1000 mm.

In one embodiment, the electrode layer 200 is a positive electrode material layer. Specifically, the positive electrode material layer includes a positive electrode active material, a first conductive agent, and a first binder.

Specifically, the positive active material is at least one selected from lithium iron phosphate, lithium manganese iron phosphate, lithium cobaltate, lithium manganate, lithium nickel manganate and nickel cobalt manganese ternary materials.

Specifically, the first conductive agent is at least one selected from acetylene black, Super P (SP), carbon nanotubes, graphene, and carbon fibers.

Specifically, the first binder is polyvinylidene fluoride (PVDF).

In another embodiment, the electrode layer 200 is a layer of negative electrode material. Specifically, the anode material layer includes an anode active material, a second conductive agent, and a second binder.

Specifically, the negative active material is at least one selected from metallic lithium, graphite, amorphous carbon, mesocarbon microbeads, silicon monomer, silicon thin film and nano silicon.

Specifically, the second conductive agent is at least one selected from acetylene black, Super P (SP), carbon nanotubes, graphene, and carbon fibers.

Specifically, the second binder is selected from at least one of Styrene Butadiene Rubber (SBR) and carboxymethyl cellulose (CMC).

The dioctyl terephthalate layer 300 is stacked on the current collector 100, and is in contact with the electrode layer 200.

Further, there are two dioctyl terephthalate layers 300, and the two dioctyl terephthalate layers 300 are respectively located at two sides of the electrode layer 200, so as to generate sufficient gas to burst the explosion-proof valve under high temperature, thereby improving the safety of the battery.

Further, the dioctyl terephthalate layer 300 and the electrode layer 200 are both in a stripe shape, and the direction in which the dioctyl terephthalate layer 300 extends is the same as the direction in which the electrode layer 200 extends.

Further, the ratio of the width of the dioctyl terephthalate layer 300 to the width of the electrode layer 200 is 1:500 to 3:40, and both the energy density and the welding process can be achieved. Specifically, the width of the dioctyl terephthalate layer 300 is 2mm to 6 mm.

Further, the thickness of the dioctyl terephthalate layer 300 is less than that of the electrode layer 200. Further, the ratio of the thickness of the dioctyl terephthalate layer 300 to the thickness of the electrode layer 200 is 2:5 to 1: 1. Specifically, the dioctyl terephthalate layer 300 has a thickness of 30 to 120 μm.

Referring to fig. 3, the electrode sheet further includes a ceramic layer 400, and the ceramic layer 400 is laminated between the dioctyl terephthalate layer and the current collector. Further, the thickness of the ceramic layer is 30 μm to 120 μm.

Specifically, the ceramic layer 400 includes alumina and polyvinylidene fluoride. More specifically, the mass percent of the aluminum oxide is 50-70%, and the mass percent of the polyvinylidene fluoride is 10-20%.

The electrode plate 10 is a positive electrode plate or a negative electrode plate.

The electrode plate 10 at least has the following advantages:

1) the dioctyl terephthalate layer 300 of the electrode tab 10 is laminated on the current collector 100 and is in contact with the electrode layer 200, and when the electrode tab 10 is in a high-temperature environment, dioctyl terephthalate starts to decompose to generate gas, so that the explosion-proof valve is broken, the battery is prevented from being ignited, and the safety of the battery is higher.

2) The electrode plate 10 further comprises a ceramic layer 400, the ceramic layer 400 can prevent burrs from piercing the electrode plate to cause short circuit, and meanwhile can play the effects of overcharge resistance and high temperature resistance, and the electrode layer 200 of the electrode plate 10 is not affected, so that the energy density of the battery is ensured.

A lithium ion battery comprises the electrode pole piece. The lithium ion battery has high safety.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. An electrode sheet, comprising:

a current collector;

an electrode layer laminated on the current collector;

2. The electrode sheet according to claim 1, wherein the number of the dioctyl terephthalate layers is two, and the two dioctyl terephthalate layers are respectively disposed on both sides of the electrode layer.

3. The electrode sheet according to claim 1, wherein the dioctyl terephthalate layer and the electrode layer are both in a stripe shape, and the direction in which the dioctyl terephthalate layer extends is the same as the direction in which the electrode layer extends.

4. The electrode sheet according to claim 1, wherein the ratio of the width of the dioctyl terephthalate layer to the width of the electrode layer is 1:500 to 3: 40.

5. The electrode tab according to claim 4, wherein the width of the dioctyl terephthalate layer is 2mm to 6mm, and the width of the electrode layer is 80mm to 1000 mm.

6. The electrode tab of claim 1 wherein the dioctyl terephthalate layer has a thickness less than the thickness of the electrode layer.

7. The electrode sheet according to claim 1, wherein the ratio of the thickness of the dioctyl terephthalate layer to the thickness of the electrode layer is 2:5 to 1: 1.

8. The electrode tab of claim 1, further comprising a ceramic layer laminated between the dioctyl terephthalate layer and the current collector.

9. The electrode tab of claim 1, wherein the electrode tab is a positive electrode tab or a negative electrode tab.

10. A lithium ion battery, characterized by comprising the electrode sheet according to any one of claims 1 to 8.