Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/04—Hybrid capacitors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
  • B01J20/04—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising compounds of alkali metals, alkaline earth metals or magnesium
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/14—Arrangements or processes for adjusting or protecting hybrid or EDL capacitors
  • H01G11/20—Reformation or processes for removal of impurities, e.g. scavenging
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/22—Electrodes
  • H01G11/30—Electrodes characterised by their material
  • H01G11/32—Carbon-based
  • H01G11/34—Carbon-based characterised by carbonisation or activation of carbon
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/54—Electrolytes
  • H01G11/58—Liquid electrolytes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
  • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
  • H01G9/004—Details
  • H01G9/02—Diaphragms; Separators
• • 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
  • H01M10/052—Li-accumulators
• • 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
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M6/00—Primary cells; Manufacture thereof
  • H01M6/14—Cells with non-aqueous electrolyte
  • H01M6/16—Cells with non-aqueous electrolyte with organic electrolyte
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M6/00—Primary cells; Manufacture thereof
  • H01M6/14—Cells with non-aqueous electrolyte
  • H01M6/16—Cells with non-aqueous electrolyte with organic electrolyte
  • H01M6/162—Cells with non-aqueous electrolyte with organic electrolyte characterised by the electrolyte
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/13—Energy storage using capacitors

Definitions

• the present invention relates to a method of removing water and other protic impurities from organic. liquid electrolytes.
• the lithium batteries (both primary and secondary battery cells) commonly used today normally contain anhydrous, liquid, ionically conducting electrolytes in which conducting salts, such as, for example, LiPF 6 , LiBF 4 , LiClO 4 , lithium imides, lithium methides or lithium chelato complexes such as, for example, lithium bis(oxalato)borate, are present in dissolved form.
• conducting salts such as, for example, LiPF 6 , LiBF 4 , LiClO 4 , lithium imides, lithium methides or lithium chelato complexes such as, for example, lithium bis(oxalato)borate.
• protic compounds such as, for example, water, for example according to
• the gaseous products (HF, POF 3 , etc.) formed during the hydrolysis of fluorine-containing conducting salts are highly corrosive and damaging to the other components of the battery, such as, for example, the cathode materials.
• HF leads to the dissolution of manganese spinels and damages the cover layer on the electrode materials that is important for a long service life.
• Borate electrolytes are also sensitive to water. In this case, in part insoluble hydrolysis products form and impair the functional properties.
• JP 208 7473 it is proposed to mix electrolyte solutions with a solvent that forms low-boiling azeotropic mixtures with water, and to remove the water/solvent azeotropic mixture by distillation.
• the disadvantages of this method are the undesired impurities with the entraining solvent and the restriction to high-boiling electrolyte solvents.
• DE 19827630 describes a method of cleaning battery electrolytes that consists in bringing a base, fixed to a solid, for the chemical adsorption of protic impurities into contact with the electrolyte solution and then separating off the solid cleaning agent. It is a disadvantage that the amine-containing cleaning agents fixed to a polymer are expensive and also require pre-treatment (e.g. drying in vacuo for 4 days at 100° C.).
• Modern supercapacitors may also contain an organic electrolyte which is generally the solution of an ammonium salt in an aprotic solvent having a high dielectric constant, such as, for example, acetonitrile or ⁇ -butyrolactone.
• the ammonium salts generally have perfluorinated anions such as PF 6 ⁇ or BF 4 ⁇ . These are electrochemically stable, not very nucleophilic and do not become incorporated into the active electrode masses.
• JP 11054378 and JP 11008163 propose adding to the electrolyte adsorbents based on inorganic oxides, for example aluminosilicates. Such adsorbents are able to lower the water content and hence improve the reliability, safety and current characteristics.
• the disadvantages of this method are on the one hand that the adsorbents must be pre-treated and on the other hand that adsorbent remains in the finished capacitor, so that the specific storage capacity is reduced.
• the object of the present invention is to avoid the disadvantages of the prior art and to provide a method of removing water and other protic impurities from organic liquid electrolytes.
• Organic liquid electrolytes are to be understood as being solutions containing lithium salts and/or ammonium salts with electrochemically resistant anions in aprotic, polar, organic solvents.
• [0019] is to yield product solutions having water contents down to ⁇ 20 ppm.
• the object is achieved by a method of removing water and other protic impurities from an organic liquid electrolyte, wherein the organic liquid electrolyte is brought into contact with one or more insoluble alkali metal hydride(s) and the insoluble reaction by-products formed thereby are separated off.
• the removal of water and other protic impurities is to be understood as meaning the partial removal to the complete removal.
• the binary hydrides of lithium (LiH) and sodium (NaH) that are used as the preferred drying agents are relatively inexpensive in large amounts and are available in pure form. Although they are completely insoluble in the aprotic solvents used for lithium batteries, it has been found that LiH, NaH and the other alkali metal hydrides KH, RbH and CsH are rapidly effective insofar as the drying operation is concerned, and very low residual contents of protic impurities can be achieved.
• the drying agents in hydride form used according to the invention are substantially more advantageous in terms of safety than the alkali metals themselves.
• the method according to the invention can be used with all organic liquid electrolytes, that is to say, for example, solutions of
• fluorides such as MPF 6 , MAsF 6 , MBF 4
• R F perfluorinated alkyl radical having from 1 to 10 carbon atoms, also cyclic
• L identity ligand having two O atoms, such as, for example, oxalate, catecholate, salicylate, also partially or wholly fluorinated
• carbonates e.g. dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, ethylmethyl carbonate,
• nitriles e.g. acetonitrile, adipic acid dinitrile, glutaric acid dinitrile,
• lactones e.g. ⁇ -butyrolactone
• amides e.g. dimethylformamide, N-methylpyrrolidone,
• ethers e.g. tetrahydrofuran, 2-methyltetrahydrofuran, 1,2-dimethoxyethane (monoglyme), 1,3-dioxolan,
• carbonic acid esters e.g. ethyl formate, propyl formate, diethyl oxalate
• boric acid esters e.g. tributyl borate, trimethyl borate
• phosphoric acid esters e.g. tributyl phosphate, trimethyl phosphate
• sulfur compounds e.g. dimethyl sulfoxide, sulfolane
• the alkali metal reacts energetically and irreversibly with proton-active substances according to;
• the hydride is preferably added in portions to the liquid electrolyte.
• the content of proton-active substances for example water, is not to exceed a particular upper limit of 0.6 mmol/g active H concentration, for example 1% water.
• drying method according to the invention can be carried out as described below by way of example.
• An alkali metal hydride is added in portions, preferably with stirring, to the moist liquid electrolyte optionally contaminated with other proton-active substances.
• This operation is preferably carried out in a temperature range from ⁇ 20 to 150° C., particularly preferably from 0 to 90° C.
• the drying operation can readily be monitored by measuring the volume of gas that develops. In some cases (mainly when significant amounts of acid are present, e.g. 0.1 mmol/g HCl), the evolution of gas is very vigorous and foaming occurs. Cooling is then necessary. Otherwise, the reaction is scarcely noticeably exothermic.
• a subsequent reaction phase at room temperature or elevated temperature (up to 90° C., sometimes up to 120 20 C.) is necessary to complete the drying.
• the amount of drying agent to be used is determined on the one hand by the “activity” of the metal hydride used and on the other hand by the concentration of the proton-active impurity—generally water.
• the water content is normally determined by Karl Fischer titration.
• the amount of drying agent used is preferably such that it corresponds at least to the amount of water determined by Karl Fischer titration (or an alternative water determination).
• the drying agent can preferably be used in a stoichiometric excess (e.g. from 2 to 100 times).
• the excess to be used in a particular case is given by the activity of the hydride and the precise manner in which the drying operation is carried out.
• the drying ability is dependent on the “active surface area” of the metal hydride, i.e. the activity is better the finer the degree of distribution of the metal hydride.
• the drying ability of the metal hydride is additionally dependent on the nature of the pre-treatment,
• the “fresher” a metal hydride the more active it is in general.
• Metal hydrides that have been in contact with air or moisture are “passivated” and must generally be activated. This may be effected by milling under an inert gas atmosphere. This operation may take place separately from the point of view of space or in situ, i.e. during drying of the electrolyte.
• the commercially available hydride grades are sufficiently active to dry an electrolyte to water contents ⁇ 20 ppm within a few hours.
• intensive stirring is preferably carried out, on a laboratory scale, for example, using a high-speed propeller stirrer. Drying may also be carried out by passing the liquid electrolyte over a fixed bed containing the metal hydride (e.g. a column).
• the clear solutions prepared in this manner have extremely low water contents (and equally low contents of other proton-active substances). They can be used without further treatment as electrolytes for electrolytic cells, preferably lithium batteries, or electrolytic two-layer capacitors (supercapacitors).

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• 2000
  • 2000-09-27 DE DE10049097A patent/DE10049097B4/de not_active Expired - Fee Related
• 2001
  • 2001-09-10 TW TW090122346A patent/TWI232126B/zh not_active IP Right Cessation
  • 2001-09-21 AU AU2002214984A patent/AU2002214984A1/en not_active Abandoned
  • 2001-09-21 US US10/381,126 patent/US20040096746A1/en not_active Abandoned
  • 2001-09-21 CA CA2424361A patent/CA2424361C/en not_active Expired - Fee Related
  • 2001-09-21 JP JP2002532321A patent/JP5021147B2/ja not_active Expired - Fee Related
  • 2001-09-21 EP EP01983490A patent/EP1330299A1/de not_active Withdrawn
  • 2001-09-21 KR KR10-2003-7004375A patent/KR20030039376A/ko not_active Application Discontinuation
  • 2001-09-21 WO PCT/EP2001/010924 patent/WO2002028500A1/de active Application Filing
  • 2001-09-21 CN CNA018195288A patent/CN1476343A/zh active Pending
• 2006
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