WO1998006666A1 - PROCEDE DE FABRICATION DE LiPF¿6? - Google Patents
PROCEDE DE FABRICATION DE LiPF¿6? Download PDFInfo
- Publication number
- WO1998006666A1 WO1998006666A1 PCT/EP1997/004359 EP9704359W WO9806666A1 WO 1998006666 A1 WO1998006666 A1 WO 1998006666A1 EP 9704359 W EP9704359 W EP 9704359W WO 9806666 A1 WO9806666 A1 WO 9806666A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- lipf
- reaction
- solvent
- lif
- hours
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0568—Liquid materials characterised by the solutes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D15/00—Lithium compounds
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D15/00—Lithium compounds
- C01D15/005—Lithium hexafluorophosphate
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
Definitions
- the invention relates to a method for producing LiPF 6 .
- This compound is used in particular as an electrolyte in batteries and as a catalyst.
- LiPF 6 can be made from LiF and PF 5 at elevated pressure and temperature.
- this implementation proceeds with a low yield and is therefore uneconomical.
- the yield can be increased by using reactive LiF which is obtained in the thermal decomposition of LiHF 2 , the production of the reactive LiF is technically complex and causes considerable costs.
- the gaseous PF 5 is not available on the market as a raw material, but must be produced immediately before the LiPF 6 is synthesized.
- the PF 5 is difficult to handle due to its toxicity and reactivity.
- LiPF 6 can also be made from red phosphorus and LiF in the presence of HF at 200 ° C in a closed reactor under pressure.
- US Pat. No. 3,607,020 proposes a process for the preparation of LiPF 6 , in which LiF is reacted with PF S in an inert organic solvent, lower saturated alkyl ethers and lower alkyl esters of aliphatic saturated monocarboxylic acids being particularly suitable as solvents.
- the PF S is readily soluble in these solvents and the process can be carried out at temperatures between 0 and 50 ° C.
- PF 5 must be synthesized immediately before the process is carried out, since this raw material is not available on the market.
- a method for producing LiPF 6 is also known from US Pat. No. 3,907,977.
- LiF is reacted with PF 5 in acetonitrile as a solvent at -40 to 80 ° C.
- the PF 5 is introduced into the LiF acetonitrile suspension at low temperatures, and the reaction mixture is then brought to 60 to Heated to 80 ° C and filtered.
- the filtered solution is cooled to 0 ° C., whereby the complex compound Li (CH 3 CN) 4 PF e precipitates.
- This complex can be freed from acetonitrile by heating to 80 ° C. in vacuo and converted into LiPF 6 .
- This process also uses the difficult to handle raw material
- the object of the invention is to provide a method for producing the aforementioned compound , which is based on generally available, inexpensive raw materials, which supplies process products of high purity and which can be carried out under the simplest possible process conditions, the use and formation of corrosive and toxic substances being avoided as far as possible.
- the object on which the invention is based is achieved by a process for the production of LiPF 6 , in which LiF with PC1 5 or POCI 3 at a reaction temperature of -20 to 300 ° C for a reaction time of 0.1 to 10 hours according to the reaction equations
- LiPF 6 is converted to LiPF 6 and in which the LiPF 6 is isolated from the reaction mixture in the form of a solution, ethers, nitriles, esters, sulfones, carbonates, halogenated hydrocarbons and / or tertiary amines being used as solvents.
- This process uses raw materials that are offered as inexpensive products on the market and which are largely available in very pure form. Although the use of pure LiF is very advantageous, it is also possible to use LiF which is contaminated with small amounts of other alkali and alkaline earth fluorides.
- the chemical reactions used for the process according to the invention provide the end product LiPF 6 in high yield, the other reaction products being easily separated and recoverable.
- the solvents required to carry out the process according to the invention, which must be acid-free and aprotic, are available in high purity and can be recovered and purified by simple processes. The required reaction times and reaction temperatures are well manageable on an industrial scale even in the presence of the raw materials required to carry out the process, because appropriate reactors are provided today by process engineering.
- Diethyl ether is preferably used as the solvent in the process according to the invention, since LiPF 6 is particularly readily soluble in diethyl ether.
- reaction times are shortened and / or the yields are increased if an excess of 0.1 to 2 mol of LiF, based on 1 mol of PC1 5 and P0C1 3, is present.
- the process according to the invention can be carried out on the one hand in such a way that the reaction first takes place at 150 to 300 ° C. for 0.1 to 5 hours and then at 60 to 120 ° C. for 0.1 to 5 hours and that the LiPF 6 then extracted at 0 to 80 ° C from the solid reaction mixture with the solvent.
- This procedure is carried out in a closed reactor under the pressure caused by the starting substances and the reaction temperature.
- PF S presumably forms in situ, which then reacts with LiF to the end product at 60 to 120 ° C.
- the end product goes into solution and can be removed from the solid reaction residue be filtered off.
- the residue consists of LiCl, LiF and optionally lithium phosphate, which can be worked up by known methods.
- the solvent used for the extraction can be purified by distillation and used again for the extraction.
- the invention provides that PC1 S and P0C1 3 during the reaction stage from PC1 3 at 150 to 300 ° C. according to the reaction equations
- the process according to the invention can be carried out in such a way that the reaction takes place for 0.1 to 5 hours at -20 to 100 ° C. in the presence of the solvent and that the LiPF 6 -containing solution is filtered off from the insoluble reaction products.
- reaction temperatures of 0-80 ° C. being preferred according to the invention.
- the reaction in the solvent proceeds with a good yield, that the LiPF c is readily soluble in the solvent and that the other reaction products can be separated off in solid form by filtration.
- the PC1 S can advantageously be reacted with LiF in the solvents diethyl ether and dimethyl, ethylene and propylene carbonate, while the solvents acetonitrile, tetrahydrofuran and methyltetrahydrofuran have proven particularly useful for the reaction of P0C1 3 with LiF.
- the inexpensive raw material PC1 3 is thus also opened up for the variant of the process according to the invention which is carried out at -20 to 100 ° C. in the presence of a solvent.
- the economy of the process according to the invention can be improved in that the solvent contains 5 to 50% by weight of liquid, aliphatic or aromatic hydrocarbons. This measure does not adversely affect the solubility of the LiPF 6 process product; however, the use of inexpensive, liquid hydrocarbons reduces process costs.
- the LiPF 6 is obtained from the LiPF 6 -containing solution by evaporating the solvent in crystalline form.
- the distillative removal of the solvent from the process product is advantageously supported by an inert gas stream and / or by distillation under reduced pressure. It was found that the organic solvents used are much easier and more residue-free to remove from the process product than HF.
- organolithium compounds in particular methyl lithium or butyllithium, or with lithium hydride. Together with water, these compounds form lithium hydroxide and hydrocarbons such as methane or butane or hydrogen.
- the lithium hydroxide can be filtered off, while the hydrocarbons or hydrogen escape from the solution in gaseous form.
- the water content of the product solutions is low anyway, since LiCl, which is used in the The inventive method is formed, is hygroscopic and therefore already largely binds the water present in the solutions.
- the drying effect of the LiCl enables the use of solvents that do not have to be quantitatively anhydrous, which advantageously reduces the costs for solvent dewatering.
- the LiPF 6 can be purified by recrystallization in the solvent, since the product is readily soluble in the solvent at elevated temperature and less readily soluble at lower temperature. Diethyl ether is particularly suitable as a solvent and for recrystallizing the LiPF 6 , the LiPF 6 being dissolved at 30 to 40 ° C. and recrystallized at 0 to 10 ° C.
- the product produced by the process according to the invention in any case has a purity> 99.0% and usually even a purity of> 99.8%.
- the product is practically anhydrous; the product-containing solutions obtained after extraction or filtration still have a water content of ⁇ 10 ppm (determined according to K. Fischer).
- the process product is marketed either in the form of solutions or in solid form.
- the product yield is generally 80 to 95% for the gas-solid reactions after the extraction and 90 to 96% for the reactions carried out in a solvent after the filtration.
- the gaseous reaction products were absorbed in sodium hydroxide solution. They contained about 1% of the phosphorus used as volatile halogen compounds.
- the white, finely powdery residue was poured into a glass apparatus under inert gas, 1500 ml of diethyl ether were added and the mixture was stirred for about 30 minutes.
- the insoluble constituents (573.4 g, consisting of a mixture of LiCl and LiF) were filtered off through a glass frit (G3) and washed three times with about 200 ml of diethyl ether.
- the water content in the combined filtrates was ⁇ 10 ppm (Karl Fischer titration).
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Organic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP97941932A EP0944550A1 (fr) | 1996-08-13 | 1997-08-11 | PROCEDE DE FABRICATION DE LiPF 6 |
JP10509396A JP2001500834A (ja) | 1996-08-13 | 1997-08-11 | LiPF▲下6▼製造方法 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19632543.9 | 1996-08-13 | ||
DE19632543A DE19632543C1 (de) | 1996-08-13 | 1996-08-13 | Verfahren zur Herstellung von LiPF¶6¶ |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998006666A1 true WO1998006666A1 (fr) | 1998-02-19 |
Family
ID=7802474
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP1997/004359 WO1998006666A1 (fr) | 1996-08-13 | 1997-08-11 | PROCEDE DE FABRICATION DE LiPF¿6? |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0944550A1 (fr) |
JP (1) | JP2001500834A (fr) |
KR (1) | KR20000016746A (fr) |
CA (1) | CA2259985A1 (fr) |
DE (1) | DE19632543C1 (fr) |
WO (1) | WO1998006666A1 (fr) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10296746B4 (de) * | 2002-03-21 | 2007-02-15 | Council Of Scientific And Industrial Research | Neues thermisches Festkörperverfahren zur Synthese von Lithiumhexafluorphosphat |
EP1976048A1 (fr) * | 2005-12-06 | 2008-10-01 | Central Glass Company, Limited | Procede de production d une solution electrolytique pour une batterie au lithium et batterie au lithium l utilisant |
US8318343B2 (en) | 2006-07-21 | 2012-11-27 | Sony Corporation | Nonaqueous electrolyte cell and positive electrode for same |
CN103213963A (zh) * | 2012-01-18 | 2013-07-24 | 彭国启 | 一种直接制备液态六氟磷酸锂的方法 |
EP3708537A1 (fr) * | 2019-03-15 | 2020-09-16 | Foosung Co., Ltd. | Procédé de production d'hexafluorophosphate de métaux alcalins, hexafluorophosphate de métaux alcalins, procédé de production de concentré d'électrolyte contenant de l'hexafluorophosphate de métaux alcalins et procédé de fabrication d'une batterie secondaire |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19805360C1 (de) * | 1998-02-12 | 1999-06-17 | Metallgesellschaft Ag | Verfahren zur Gewinnung von reinem, grobkristallinen LiPF¶6¶ aus einer Lösung von LiPF¶6¶ in Diethylether |
DE19805356C1 (de) * | 1998-02-12 | 1999-06-17 | Metallgesellschaft Ag | Verfahren zur Herstellung von reinem LiPF¶6¶ |
DE19824984A1 (de) * | 1998-06-04 | 1999-12-09 | Basf Ag | Verfahren zur Kristallisation von hochreinem LiPF¶6¶ aus organischen Lösungsmitteln |
JP5609283B2 (ja) * | 2010-06-08 | 2014-10-22 | セントラル硝子株式会社 | リチウムイオン電池用電解液の製造方法およびそれを用いたリチウムイオン電池 |
CN103964409B (zh) * | 2013-02-05 | 2018-04-10 | 关东电化工业株式会社 | 高纯度LiPF6的制造方法 |
CN108439362A (zh) * | 2018-05-18 | 2018-08-24 | 青海聚之源新材料有限公司 | 一种高端六氟磷酸锂的制备方法 |
CN109019550A (zh) * | 2018-10-16 | 2018-12-18 | 河南工程学院 | 一种有机溶剂制备六氟磷酸锂的方法 |
CN110817831A (zh) * | 2019-11-25 | 2020-02-21 | 湖北迈可凯科技有限公司 | 一种六氟磷酸锂的连续合成方法及装置 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3607020A (en) * | 1970-03-19 | 1971-09-21 | Foote Mineral Co | Preparation of lithium hexafluorophosphate |
GB1360764A (en) * | 1971-12-27 | 1974-07-24 | Gte Laboratories Inc | Electrochemical cell |
US3907977A (en) * | 1969-05-29 | 1975-09-23 | United States Steel Corp | Method for the preparation of high purity, highly surface active LiAsF{HD 6 |
JPS60251109A (ja) * | 1984-05-28 | 1985-12-11 | Daikin Ind Ltd | 6−フツ化リン酸リチウムの製造法 |
JPH04175216A (ja) * | 1990-11-09 | 1992-06-23 | Tohkem Prod:Kk | 高純度六フツ化リン酸化合物の製造方法 |
JPH05279003A (ja) * | 1992-03-31 | 1993-10-26 | Morita Kagaku Kogyo Kk | 6フッ化リン酸リチウムの製造法 |
-
1996
- 1996-08-13 DE DE19632543A patent/DE19632543C1/de not_active Expired - Fee Related
-
1997
- 1997-08-11 EP EP97941932A patent/EP0944550A1/fr not_active Ceased
- 1997-08-11 JP JP10509396A patent/JP2001500834A/ja active Pending
- 1997-08-11 KR KR1019980710353A patent/KR20000016746A/ko not_active Application Discontinuation
- 1997-08-11 WO PCT/EP1997/004359 patent/WO1998006666A1/fr not_active Application Discontinuation
- 1997-08-11 CA CA002259985A patent/CA2259985A1/fr not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3907977A (en) * | 1969-05-29 | 1975-09-23 | United States Steel Corp | Method for the preparation of high purity, highly surface active LiAsF{HD 6 |
US3607020A (en) * | 1970-03-19 | 1971-09-21 | Foote Mineral Co | Preparation of lithium hexafluorophosphate |
GB1360764A (en) * | 1971-12-27 | 1974-07-24 | Gte Laboratories Inc | Electrochemical cell |
JPS60251109A (ja) * | 1984-05-28 | 1985-12-11 | Daikin Ind Ltd | 6−フツ化リン酸リチウムの製造法 |
JPH04175216A (ja) * | 1990-11-09 | 1992-06-23 | Tohkem Prod:Kk | 高純度六フツ化リン酸化合物の製造方法 |
JPH05279003A (ja) * | 1992-03-31 | 1993-10-26 | Morita Kagaku Kogyo Kk | 6フッ化リン酸リチウムの製造法 |
Non-Patent Citations (3)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 010, no. 123 (C - 344) 8 May 1986 (1986-05-08) * |
PATENT ABSTRACTS OF JAPAN vol. 016, no. 479 (C - 0992) 6 October 1992 (1992-10-06) * |
PATENT ABSTRACTS OF JAPAN vol. 018, no. 061 (C - 1160) 2 February 1994 (1994-02-02) * |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10296746B4 (de) * | 2002-03-21 | 2007-02-15 | Council Of Scientific And Industrial Research | Neues thermisches Festkörperverfahren zur Synthese von Lithiumhexafluorphosphat |
EP1976048A1 (fr) * | 2005-12-06 | 2008-10-01 | Central Glass Company, Limited | Procede de production d une solution electrolytique pour une batterie au lithium et batterie au lithium l utilisant |
EP1976048A4 (fr) * | 2005-12-06 | 2008-12-24 | Central Glass Co Ltd | Procede de production d une solution electrolytique pour une batterie au lithium et batterie au lithium l utilisant |
US8771882B2 (en) | 2005-12-06 | 2014-07-08 | Central Glass Company, Limited | Method for producing electrolyte solution for lithium ion battery and lithium ion battery using same |
US8318343B2 (en) | 2006-07-21 | 2012-11-27 | Sony Corporation | Nonaqueous electrolyte cell and positive electrode for same |
CN103213963A (zh) * | 2012-01-18 | 2013-07-24 | 彭国启 | 一种直接制备液态六氟磷酸锂的方法 |
CN103213963B (zh) * | 2012-01-18 | 2016-02-24 | 彭国启 | 一种直接制备液态六氟磷酸锂的方法 |
EP3708537A1 (fr) * | 2019-03-15 | 2020-09-16 | Foosung Co., Ltd. | Procédé de production d'hexafluorophosphate de métaux alcalins, hexafluorophosphate de métaux alcalins, procédé de production de concentré d'électrolyte contenant de l'hexafluorophosphate de métaux alcalins et procédé de fabrication d'une batterie secondaire |
Also Published As
Publication number | Publication date |
---|---|
DE19632543C1 (de) | 1998-04-02 |
JP2001500834A (ja) | 2001-01-23 |
CA2259985A1 (fr) | 1998-02-19 |
KR20000016746A (ko) | 2000-03-25 |
EP0944550A1 (fr) | 1999-09-29 |
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