Method for removing trace impurities in lithium bis (fluorosulfonyl) imide

A technology for lithium bisfluorosulfonimide and bisfluorosulfonimide salt is applied in the field of removing trace impurities in lithium bisfluorosulfonimide, and can solve the problems of difficulty in removing trace impurities and the like

Inactive Publication Date: 2021-11-05
ZHANGJIAGANG HUASHENG CHEM CO LTD
View PDF5 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Aiming at the problems such as the difficult removal of trace impurities caused in the current purification process of bisfluorosulfonyl imi...

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0050] Mix 500 grams of bisfluorosulfonimide lithium salt (index: ion chromatography content 95.8%, acid value 361ppm, anion is 7308ppm of sulfate radical impurities, anion is 273ppm of fluoride ion impurities) and inert solvent 1,2-dichloro Ethane 750 g mixed. Then, 750 g of diethyl ether was added dropwise, and the internal temperature was controlled to be 10° C. during the dropwise addition. After the dropwise addition was completed, the solution was stirred and dissolved for 5 hours. Then filter with a filter of 500 mesh lining polytetrafluoroethylene material, the gained filtrate is transferred in the impurity removal container with stirring, is cooled to 8 ℃, then adds impurity removal agent lithium carbonate 0.25 grams. Start stirring to allow the impurity remover and impurities to fully react for 4 hours. Sampling and testing all indicators are qualified (acidic impurities ≤ 100ppm is qualified), then filter, otherwise continue to add 0.25 grams of impurity remover li...

Embodiment 2

[0053] Mix 500 grams of bisfluorosulfonimide lithium salt (indicators: ion chromatography content 94.7%, acid value 561ppm, anion as sulfate impurity 5308ppm, anion as fluoride ion impurity 273ppm, anion as fluorosulfonate impurity 430ppm) and an inert solvent Mix 750 g of 1,1,2-trichloroethane. Then, 750 g of methyl acetate was added dropwise, and the internal temperature was controlled to be 8° C. during the dropwise addition. After the dropwise addition, stir and dissolve for 4 hours, then filter with a 600-mesh stainless steel filter, transfer the resulting filtrate to a stirring impurity removal container, cool down to 9°C, and then add impurity removal agents lithium bicarbonate and lithium methoxide 0.3 grams each , start stirring to allow the impurity remover and impurities to fully react for 5 hours, take a sample to detect that all indicators are qualified (acidic impurities ≤ 100ppm is qualified), then filter, otherwise continue to add impurity remover Lithium bicar...

Embodiment 3

[0056] Mix 500 grams of bisfluorosulfonimide lithium salt (index: ion chromatography content 96.3%, acid value 561ppm, anion as fluoride ion impurity 373ppm, anion as sulfamic acid radical impurity 260ppm) and inert solvent 1,1,2,2 - Tetrachloroethane 750 g mixed. Then 750 grams of acetonitrile was added dropwise, and the internal temperature was controlled to be 7° C. during the dropwise addition. After the dropwise addition, it was stirred and dissolved for 6 hours, and then filtered with an 800-mesh stainless steel filter, and the resulting filtrate was transferred to a stirring container for removing impurities. Cool down to 7°C, then add 0.4 grams of impurity remover lithium methoxide and lithium oxalate, start stirring to allow the impurity remover and impurities to fully react for 6 hours, take samples and test all indicators are qualified (acidic impurities ≤ 100ppm is qualified), then filter , otherwise continue to add 0.4 grams each of lithium methoxide and lithium o...

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
Acid valueaaaaaaaaaa
Acid valueaaaaaaaaaa
Login to view more

Abstract

The invention relates to a method for removing trace impurities in lithium bis (fluorosulfonyl) imide, which comprises the following steps: (1) adding a good solvent into a mixture of lithium bis (fluorosulfonyl) imide and an inert solvent, and filtering to provide a first filtrate; (2) adding an impurity removal agent into the filtrate to form a mixed solution, and filtering to provide a second filtrate; and (3) carrying out reduced pressure distillation on the second filtrate to provide a finished product of the bis (fluorosulfonyl) imide lithium salt. The indexes of the lithium bis (fluorosulfonyl) imide salt finished product accord with one or a combination of more of the following items: the ion chromatography content is greater than or equal to 99.5%, sulfate radical impurity anions are less than or equal to 100ppm, fluorine ion impurity anions are less than or equal to 200ppm, sulfamic acid content anions are less than or equal to 10ppm, fluorine sulfonic acid impurity anions are less than or equal to 10ppm, acidic impurities are less than or equal to 100ppm, the turbidity of the 10% dimethyl carbonate solution is smaller than or equal to 20 mg/L, and the chromaticity is smaller than or equal to 20 Hazen.

Description

technical field [0001] The invention relates to an electrolyte salt for power batteries and energy storage batteries, in particular to a method for removing trace impurities in lithium bisfluorosulfonyl imide. Background technique [0002] As the country vigorously promotes the "carbon peak" and "carbon neutral" plans, the new energy industry chain will usher in vigorous development, which includes new energy vehicles, photovoltaics, wind power and other renewable energy storage industries. develop. The development of these industries is inseparable from high-performance power batteries or energy storage batteries. At this stage, liquid ion batteries are the most cost-effective, and the electrolyte salts related to them are the key materials that can determine the excellent performance of batteries. Among the many electrolyte salts, the bisfluorosulfonimide salt has the best overall performance. Among them, bisfluorosulfonimide lithium salt is the most promising alternati...

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
IPC IPC(8): C01B21/086
CPCC01B21/086C01P2006/80
Inventor 吴国栋袁青海李伟锋曹秀坤周立新
Owner ZHANGJIAGANG HUASHENG CHEM 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