Negative plate and lithium ion battery comprising same

A lithium-ion battery and negative electrode technology, which is applied in the direction of negative electrodes, battery electrodes, secondary batteries, etc., can solve the problems of poor charging and discharging effects at large rates and high discharge specific capacity, and achieve rapid transmission and isotropic Good, the effect of improving power performance

Pending Publication Date: 2022-03-01
ZHUHAI COSMX BATTERY CO LTD
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Because spherical natural graphite particles have good isotropy and high discharge specific capacity, they have advantages over artificial graphite in high-rate charge and discharge. However, in low-temperature electrolyte systems, natural graphite anode materials have a large Poor rate charge and discharge effect

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
  • Negative plate and lithium ion battery comprising same
  • Negative plate and lithium ion battery comprising same

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0041] Preparation of the negative electrode sheet: at 25°C, the negative electrode material prepared in the following examples and comparative examples was mixed with carboxymethyl cellulose (CMC), conductive carbon black, and styrene-butadiene rubber (SBR) in a mass ratio of 92% : 1.5% : 1.5% : 5% were mixed evenly in pure water to prepare negative electrode slurry 1; evenly coated negative electrode slurry 1 on 8μm copper foil, the coating surface density was about 8mg / cm 2 , and then put the copper foil in a vacuum drying oven at 80°C for 12 hours. Cut the dried pole piece into a disc with a diameter of 20mm to make a working electrode.

[0042] (2) Assembly of the half-cell: at room temperature, with the metal lithium sheet as the counter electrode, the above-mentioned working electrode, the polyethylene diaphragm as the battery diaphragm, and 1mol / L LiPF 6 / EC:DEC (volume ratio is 1:1) solution is the electrolyte, and it is assembled into a CR2430 button battery in a gl...

Embodiment 1

[0053] (1) Preparation of negative electrode active material: Spherical graphite raw material is obtained after flake graphite is pulverized, shaped and spheroidized, and the raw material is subjected to mechanical treatment, asphalt coating modification, carbonization heat treatment and sieving and demagnetization to obtain natural graphite negative electrode active material .

[0054] According to the test, the particle size distribution of the negative active material is: Dv50=7.3μm, Dv10=4.2μm, Dv90=10.5μm; the tap density is 1.05g / cm 3 ;The specific surface area is 1.8m 2 / g; the discharge specific capacity of the half-cell is 364mAh / g, and the initial efficiency is 92.4%; the OI value of the powder, I004 / I110 is 4.38.

[0055] figure 1 is the SEM figure of the negative electrode active material in embodiment 1, by figure 1 It can be seen from the figure that the particle size of the natural graphite negative electrode active material is small, its particle size distri...

Embodiment 2

[0060] (1) Preparation of the negative electrode active material: refer to the preparation method of the negative electrode active material in Example 1 to obtain the natural graphite negative electrode active material.

[0061] It can be seen from the test that the particle size distribution of the negative electrode active material is: Dv50=7.6 μm, Dv10=4.0 μm, Dv90=11.0 μm; the tap density is 1.08 g / cm 3 ;The specific surface area is 1.2m 2 / g; the discharge specific capacity of the half-cell is 362mAh / g, and the initial efficiency is 92.6%; the powder OI value I004 / I110 is 2.10.

[0062] (2) The preparation of the negative electrode sheet and the full battery is the same as in Example 1, and a soft pack battery 2 is obtained.

[0063] The test results of pouch battery 2 are: at 25°C 3C / 3C cycle for 1000 cycles, the capacity retention rate is 91%, the battery thickness expansion rate is 9.4%, and the -20°C discharge capacity retention rate is 93%, see Table 1 for details ...

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

PropertyMeasurementUnit
specific surface areaaaaaaaaaaa
densityaaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention provides a negative plate and a lithium ion battery comprising the same. The negative plate contains a negative active material, and the negative active material has the following characteristics: the particle size distribution Dv10/Dv90 is greater than 0.35; the specific surface area is 2-3m < 2 >/g; and the tap density is 1.0-1.3 g/cm < 3 >. The high-rate charge-discharge performance of the negative plate is excellent, the low-temperature charge-discharge polarization of the negative plate is smaller, the start-stop/HEV lithium ion battery has excellent performance in low-temperature high-rate charge-discharge, and the application prospect of the negative plate is wide.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and more specifically, the invention relates to a negative electrode sheet and a lithium ion battery including the negative electrode sheet. Background technique [0002] Since SONY first successfully developed lithium-ion batteries in 1990, lithium-ion batteries are becoming more and more popular among consumers. It has the characteristics of high output voltage, high energy density, small self-discharge, no memory effect and wide operating temperature range (-20℃~60℃), so it is widely used in consumer electronics, electric vehicles, electric tools, energy storage power stations and other fields more and more widely. [0003] Lithium-ion battery technology has been developed for more than 30 years, and its manufacturing technology is becoming more and more mature. Coupled with the country's strong support for the new energy industry, the lithium-ion battery industry is booming. H...

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 Applications(China)
IPC IPC(8): H01M4/133H01M4/587H01M10/0525
CPCH01M4/587H01M10/0525H01M4/133H01M2004/027H01M2004/021Y02E60/10
Inventor 刘盼刘春洋陈若凡李素丽李俊义徐延铭
Owner ZHUHAI COSMX BATTERY 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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap