A kind of electrolytic solution, positive pole and its preparation method and a kind of lithium ion battery

An electrolyte and cathode technology, applied in battery electrodes, secondary batteries, organic electrolytes, etc., can solve the problems of battery cycle performance degradation, side reactions, oxidative decomposition batteries, etc., and achieve the effect of improving cycle performance and prolonging life.

Active Publication Date: 2019-12-20
BYD CO LTD
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At this stage, most lithium battery electrolyte systems can only be used stably at a voltage of 4.2v and below. When the working voltage reaches above 4.2v, the electrolyte system will oxidize and decompose, making the battery unable to work normally. The application of high-voltage cathode materials has formed a great obstacle, and the battery cycle performance is reduced
[0003] The above-mentioned electrolyte also has the technical problem that the electrolyte solvent is prone to side reactions with the positive electrode at a high potential, so that the solvent is further oxidized and decomposed, resulting in excessive consumption of the electrolyte solvent

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A kind of electrolytic solution, positive pole and its preparation method and a kind of lithium ion battery
  • A kind of electrolytic solution, positive pole and its preparation method and a kind of lithium ion battery
  • A kind of electrolytic solution, positive pole and its preparation method and a kind of lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0060] The invention provides a method for preparing a positive electrode, comprising:

[0061] (1) Forming a positive electrode material layer on the surface of the positive electrode current collector;

[0062] (2) The electrolytic solution described in any one of claims 1-9 is contacted with the positive electrode material layer surface, and the voltage during contact is 3.5V-4.2V.

[0063] The present invention provides a positive electrode prepared by the above method.

[0064] The preparation method of lithium-ion battery electrolyte is a common method for those skilled in the art, that is, to mix all components (including lithium salt, electrolyte solvent and additives) uniformly, and the method and order of mixing are not particularly limited in the present invention.

[0065] The present invention also provides a lithium-ion battery, comprising a casing, an electric core contained in the casing, and an electrolyte, the electric core includes a positive electrode, a n...

Embodiment 1

[0079] (1) Preparation of electrolyte:

[0080] In an argon glove box, ethylene carbonate (EC), diethyl carbonate (DEC), 12% by weight lithium hexafluorophosphate (LiPF 6 ) was dissolved in 100% by weight of the electrolyte solvent, and then 0.1% by weight of 1,3,5-trimethylborazine (the borazine of the structure shown in the formula (1) of this application, wherein R 1 , R 3 , R 5 Both are -H, R 2 , R 4 , R 6 for -CH 3 , obtain the lithium-ion battery electrolyte of the present embodiment, be denoted as C1;

[0081] (2) Preparation of lithium ion battery:

[0082] The positive active material (LiNi 1 / 3 co 1 / 3 mn 1 / 3 o 2 ), acetylene black, and polyvinylidene fluoride in a ratio of 90:5:5 and then pressed on the aluminum foil to obtain the positive electrode sheet; the metal lithium sheet was used as the negative electrode sheet; the PE / PP composite diaphragm was used as the ion exchange membrane. The electrolyte C1 of the example is made into a button battery S1 b...

Embodiment 2

[0084] Electrolyte and button cell are prepared in the same steps as in Example 1, the difference is that in step (1), 0.5% by weight of tri-chloroborazine is used to replace 1,3,5-trimethylcyclo Borazane, Li-ion battery electrolyte C2 and button battery S2 were prepared.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides an electrolyte comprising a lithium salt, an electrolyte solvent and an additive, wherein the additive is a boron nitrogen alkane compound having a structure as shown in formula (1), wherein R1, R3 and R5 are -H, R2, R4 and R6 are independently selected from one or more of -F, -Cl, -Br, CH3(CH2) n-, CX3 (CH2) n1-, CX2H (CH2) n2-, CHX2 (CH2) n3-, phenyl and difluorophenyl; or R2, R4 and R6 are -H, and R1, R3 and R5 are independently selected from one or more of -F, -Cl, -Br, CH3(CH2) n-, CX3 (CH2) n1-, CX2H (CH2) n2-, CHX2 (CH2) n3-, phenyl and difluorophenyl, wherein the X is selected from one or more of F, Cl, -Br and I, n is not smaller than 0 and is not greater than 3, n1 is not smaller than 0 and is not greater than 3, n2 is not smaller than 0 and is not greater than 3, and n3 is not smaller than 0 and is not greater than 3. The invention further discloses an anode, a preparation method of the anode and a lithium ion battery. In the electrolyte provided by the invention, the boron nitrogen alkane compound having the structure is used as the specific additive, so that the anode can be protected from being damaged, and meanwhile the oxygenolysis (excessive consumption) of the electrolyte solvent is protected, therefore the service life of the battery under high voltage is prolonged.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, and in particular relates to an electrolyte, a positive electrode, a preparation method thereof and a lithium ion battery. Background technique [0002] Since the 1990s, lithium-ion secondary batteries have developed rapidly from their birth. Generally speaking, a lithium-ion battery with an electrolyte includes a casing, a cell contained in the casing, and an electrolyte. The cell includes a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. During charging, lithium ions migrate from the positive electrode through the electrolyte to the negative electrode, while they flow in the opposite direction during discharging. In recent years, secondary lithium-ion batteries with high energy density have become the object of people's attention. Therefore, people have also noticed some new active materials that can be used as secondary ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H01M10/0567H01M4/131H01M4/1391H01M4/36H01M4/525H01M4/62H01M10/0525
CPCH01M4/131H01M4/1391H01M4/366H01M4/525H01M4/628H01M10/0525H01M10/0567H01M2300/0025Y02E60/10
Inventor 乔飞燕王圣
Owner BYD CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products