Functional additive applied to non-aqueou electrolyte of lithium ion battery

A technology of functional additives and non-aqueous electrolytes, applied in the field of electrolytes, can solve problems affecting battery cycle performance and battery system performance degradation, and achieve the effects of improving cycle performance, low cost, and good application prospects

Inactive Publication Date: 2012-02-01
HEFEI GUOXUAN HIGH TECH POWER ENERGY
View PDF3 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the above-mentioned positive electrode materials will cause the dissolution of active metal ions due to the generation of HF or other acidic substances in the electrolyte during use, thereby seriously affecting the cycle performance of the battery. This phenomenon is particularly serious at high temperatures, J Power Sources (2004 , 129:14-19), J Electrochem Soc (2005, 152(6): A1041-A1046) and Flectrochem Communica (2005, 7: 669-673) and other documents have confirmed this point
In addition, the attenuation of high-voltage materials is also closely related to the composition of the electrolyte. The current conventional electrolyte system will decompose when the voltage is higher than 4.5V, resulting in a decline in the performance of the entire battery system.

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
  • Functional additive applied to non-aqueou electrolyte of lithium ion battery
  • Functional additive applied to non-aqueou electrolyte of lithium ion battery
  • Functional additive applied to non-aqueou electrolyte of lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0017] Prepare 1M LiPF 6 The basic electrolyte of EC / EMC / DEC (1:1:1w), adding 1.0wt% additive HQ to the basic electrolyte to make a new electrolyte, tested the electrolyte and LiFePO with a three-electrode system on a CHI660D electrochemical workstation 4 Positive compatibility. The working electrode was prepared by uniformly mixing the lithium iron phosphate sample, conductive carbon black and polytetrafluoroethylene at a mass ratio of 82:10:8, and the reference electrode and the counter electrode were metal lithium sheets. figure 1 for LiFePO 4 From the cyclic voltammograms in the two electrolytes, it can be seen that the additive HQ does not affect the normal deintercalation of lithium ions in the electrode material.

Embodiment 2

[0019] Mix graphite, binder and conductive agent in a ratio of 90:2:8 to make negative electrode slurry, evenly coat it on copper foil, and dry it at 80°C for 60 minutes to make lithium ion battery negative electrode sheet. Test of 1M LiPF with additive HQ using three-electrode system on CHI660D electrochemical workstation 6 Compatibility of EC / EMC / DEC (1:1:1w) basic electrolyte with graphite anode. figure 2 The cyclic voltammogram of graphite anode in the basic electrolyte containing 1wt% additive HQ is given, which shows that the additive HQ has good compatibility with graphite anode.

Embodiment 3

[0021] At 1M LiPF 6 Add 0.5wt% additive HQ to the EC / EMC / DEC (1:1:1w) basic electrolyte, then seal the electrolyte and place it in a vacuum drying oven in a vacuum glove box with a moisture content of less than 5ppm, at 45°C It was stored under high temperature for 2 days, and the changes of moisture and HF content in the electrolyte before and after high temperature storage treatment were investigated. The moisture content was measured by Karl Fischer potentiometric titrator, and the HF content was analyzed by acid-base neutralization titration. Table 1 shows the change values ​​of moisture and HF content in the electrolyte before and after treatment at 45 °C. It can be seen that the additive HQ can effectively inhibit the generation of HF in the electrolyte and improve the stability of the electrolyte.

[0022] Table 1

[0023]

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 discloses a functional additive applied to non-aqueou electrolyte of a lithium ion battery. The use level of the functional additive equivalently accounts for 0.01-5% of the mass of the electrolyte consisting of a carbonate ester solvent and a lithium salt, and preferentially accounts for 0.05-1.5% of the mass of the electrolyte. By applying the additive disclosed by the invention, the high-temperature cycle performance of the lithium ion battery can be effectively improved, meanwhile, the oxidation resistance of the conventional carbonate ester type electrolyte can be increased to 5.0V. The additive disclosed by the invention is low in cost and obvious in effect and has a better application prospect.

Description

technical field [0001] The invention relates to an electrolyte solution of a lithium ion battery, in particular to a functional additive for the electrolyte solution of a lithium ion battery for improving battery cycle performance and increasing electrolyte decomposition voltage. Background technique [0002] Lithium-ion batteries have become a research hotspot in the field of new energy due to their high operating voltage, high energy density and long cycle life. The currently used cathode material for lithium-ion batteries, LiCoO 2 , LiMn 2 o 4 and LiFePO 4 The operating voltage of other materials is lower than 4V, with LiNi 0.5 mn 1.5 o 4 and LiCoPO 4 The discharge voltage of the high-voltage positive electrode material represented by the material such as can be as high as about 5V. However, the above-mentioned positive electrode materials will cause the dissolution of active metal ions due to the generation of HF or other acidic substances in the electrolyte duri...

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): H01M10/0567
CPCY02E60/122H01M10/0567Y02E60/12H01M10/0525Y02E60/10
Inventor 杨续来陈燕刘成士刘大军张羽
Owner HEFEI GUOXUAN HIGH TECH POWER ENERGY
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