A kind of high-rate lithium-ion battery, aging and formation method

A lithium ion battery, a technology of chemical formation method, applied in battery electrodes, secondary batteries, electrochemical generators, etc., can solve the problems of electrolyte decomposition, poor infiltration effect of pole pieces, limited effect, etc., and achieve strong mechanical stability, Excellent performance and the effect of promoting uniform infiltration

Active Publication Date: 2021-01-22
郑州中科新兴产业技术研究院
View PDF27 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the high working current of high-rate lithium-ion batteries, the electrolyte will decompose during use, especially for large-capacity, small-sized and thick batteries. The SEI film is easy to decompose at high temperature, which seriously affects the service life of the battery
[0003] In view of the above problems, Chinese patents (application publication numbers CN 108574115 A, CN 106099202 A) all report a method of forming, in which the battery is pre-pressed and shaped before being formed, and the pre-pressed and shaped are all carried out after aging. The sheet contact is not tight, which is not conducive to the infiltration of electrolyte
Chinese patents (application publication number CN 107579281 A, application publication number CN108306062 A) respectively use the method of fractional injection, multiple standing and vacuum gradient standing to improve the wettability of the electrolyte, but these two methods are external physics. The auxiliary method promotes the wettability of the electrolyte, but does not significantly increase the retention of the electrolyte; it is aged in a hot-pressed fixture, but there is no explanation for the aging pressure system
The disadvantage of the above process is that although the formation of the hot-pressed fixture can make the contact of the pole piece better, the time spent in the formation of the SEI film is short, which is not conducive to the stability of the SEI film structure of the pole piece, and subsequent aging is still required to improve the SEI film. stability
Although this formation scheme can produce a lithium battery with good cycle performance, its disadvantage is that it has a good effect on other small and thin batteries, but it has limited effect on large capacity, small and thick batteries.
In addition, only increasing the residence time of the battery at a specific voltage (cut-off voltage after each precharge) will cause the SEI film on the surface of the wetted and incompletely wetted negative electrode particles to be in different stages, which is not conducive to the formation of a uniform and stable SEI film

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 high-rate lithium-ion battery, aging and formation method
  • A kind of high-rate lithium-ion battery, aging and formation method
  • A kind of high-rate lithium-ion battery, aging and formation method

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0045] The preparation method of the high-rate battery is as follows:

[0046] Positive plate preparation: According to lithium cobaltate 90%, superconducting carbon black 2%, carbon nanotube 3.5%, polyvinylidene fluoride 4.5%, weigh each raw material, dissolve polyvinylidene fluoride in solvent (NMP), low speed 20rpm / min, high speed 1200rpm / min, stirring and dispersing for 90min to prepare glue; then add half of the superconducting carbon black to the glue, high speed 40rpm / min, high speed dispersing 2500rpm / min, stirring and dispersing time 60min, get a conductive glue; then add the other half of the superconducting carbon black into the primary conductive glue, stir at a high speed of 40rpm / min, and disperse at a high speed of 2500rpm / min for 60min to obtain a secondary conductive glue; add CNTS to the secondary In the conductive glue, the stirring speed is 40rpm / min, the dispersion speed is 3000rpm / min, the stirring and dispersing time is 60min, and the conductive glue is...

Embodiment 1

[0051] The A1, B1, and C1 batteries prepared above are subjected to the following formation operations:

[0052] High temperature aging steps:

[0053] Step 1: Preheat the cell at 45°C for 20 minutes, and then pre-press and shape it. The shaping pressure is 50Kg and the time is 20 minutes;

[0054] Step 2: Release the pressure to 0Kg, age at a high temperature for 48 hours, and the aging temperature is 45°C; after the aging, keep the temperature and increase the pressure to 800Kg until the formation is completed.

[0055] The first step of formation:

[0056] Step 1: Charge to 10% of the design capacity of the battery at a constant current of 0.1C, set aside for 4 hours at a high temperature of 45°C and a pressure of 800Kg;

[0057] Step 2: Discharge at a constant current of 0.1C to 4% of the battery design capacity, and let it stand for 10 minutes;

[0058] Step 3: Charge to 10% of the design capacity of the battery with a constant current of 0.1C, and let it stand for 10 ...

Embodiment 2

[0086] A3 batteries were taken for different aging-formation operations, and the batteries were pumped and sealed to prepare a 16Ah pouch battery. When the battery is formed, only the charge and discharge rate of the first stage of formation is changed from 0.1C to 0.2C; the rate of charge and discharge of the second stage of formation is changed from 0.2C to 0.4C; C, all the other parameters and operations are the same as in Example 1. The specific steps are as follows:

[0087] High temperature aging steps:

[0088] Step 1: Preheat the cell at 45°C for 20 minutes, and then pre-press and shape it. The shaping pressure is 50Kg and the time is 20 minutes;

[0089] Step 2: Release the pressure to 0Kg, age at a high temperature for 48 hours, and the aging temperature is 45°C; after the aging, keep the temperature and increase the pressure to 800Kg until the formation is completed.

[0090] The first step of formation:

[0091] Step 1: Charge to 10% of the design capacity of t...

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
porosityaaaaaaaaaa
porosityaaaaaaaaaa
porosityaaaaaaaaaa
Login to view more

Abstract

The invention provides a high-rate lithium-ion battery, aging and formation methods. The effectiveness of the high porosity of the pole piece lies in the ability to increase the electrolyte retention and wettability of the pole piece. The compounding of the conductive agent is used to reduce the direct current of the battery. Internal resistance; during aging, first preheat and soften the battery at high temperature, and then perform pre-pressurization and pressure relief operations to reshape the battery, and high-temperature aging promotes the uniform infiltration of the electrolyte on the coating layer of the pole piece; a three-step hot-press formation system is adopted , after the completion of each step of constant current charging, adding the "high temperature shelving aging-constant current discharge-constant current charging" step can further improve the wetting effect of the electrolyte and make the SEI film have sufficient nucleation, growth and reformation time , The charge-discharge cycle can make the SEI film on the surface of the negative electrode active material particles more fully formed. The lithium-ion battery prepared by the invention is suitable for fields such as unmanned aerial vehicles, electric tools, start-stop power supplies, etc., which require high battery power performance.

Description

technical field [0001] The invention relates to the technical field of lithium-ion battery manufacturing, in particular to a high-rate lithium-ion battery, aging and formation methods. Background technique [0002] As a new type of clean energy, lithium-ion batteries have the advantages of high working voltage, high energy density, and light weight. They have been widely used in 3C consumer fields, new energy vehicles, and drones. With the continuous expansion of lithium battery application scenarios, the market has a great demand for high-rate and long-life lithium batteries. However, due to the high working current of high-rate lithium-ion batteries, the electrolyte will decompose during use, especially for large-capacity, small-sized and thick batteries. The SEI film is easy to decompose at high temperature, which seriously affects the service life of the battery. [0003] In view of the above problems, Chinese patents (application publication numbers CN 108574115 A, CN...

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): H01M4/62H01M4/04H01M10/0525H01M10/058H01M10/44
CPCY02E60/10Y02P70/50
Inventor 张锁江刘艳侠张若涛赵冲冲李蒙任岘乐张治博马安博
Owner 郑州中科新兴产业技术研究院
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