WO1999019921A1

WO1999019921A1 - MIXTURES WITH Li-CONTAINING SOLIDS SUITABLE AS SOLID ELECTROLYTES OR SEPARATORS FOR ELECTROCHEMICAL CELLS

Info

Publication number: WO1999019921A1
Application number: PCT/EP1998/005854
Authority: WO
Inventors: Stephan Bauer; Bernd Bronstert; Helmut MÖHWALD; Hans-Josef Sterzel
Original assignee: Basf Aktiengesellschaft
Priority date: 1997-10-09
Filing date: 1998-09-15
Publication date: 1999-04-22
Also published as: TW391073B; AU9743898A

Abstract

A mixture (Ia) containing a mixture (IIa) comprises (a) 1-95 wt. % of a Li-ion-conducting solid (III), preferably a basic solid (III), with a primary particle size between 5 nm and 20 νm; (b) 5-99 wt. % of a polymer mass (IV) obtained by polymerising (b1) 5-100 wt. %, with respect to the mass (IV), of a condensation product (V) and (b2) 0-95 wt. %, with respect to the mass (IV), of another compound (VIII) having a mean molecular weight (numeric average) of at least 5000 with polyether segments in the main or side chain, the proportion by weight of mixture (IIa) in the mixture (Ia) amounting to 1-100 wt. %.

Description

Mixtures with lithium-containing solids suitable as solid electrolyte or separator for electrochemical cells

The present invention relates to mixtures which, inter alia, are suitable for electrochemical cells with lithium ion-containing electrolytes; their use e.g. in solid electrolytes, separators and electrodes; Solid electrolytes, separators. Electrodes, sensors, electrochromic windows, displays, capacitors and ion-conducting foils containing such a mixture; electrochemical cells with such solid electrolytes, separators and / or electrodes; and the use of the solids in the mixtures in electrochemical cells to improve the cycle stability.

Electrochemical, in particular rechargeable, cells are generally known, for example from "Ullmann's Encyclopedia of Industrial Chemistry", 5th ed. , Vol A3, VCH Verlagsgesellschaft mbH, Weinheim. 1985, pages 343-397.

Among these cells, the lithium batteries and the lithium ion batteries, in particular as secondary cells, occupy a special position due to their high specific energy storage density.

Such cells contain, in the cathode, as described, inter alia, in the above quotation from "Ullmann", lithiated manganese, cobalt, vanadium or nickel mixed oxides, such as in the simplest stoichiometric case as LiMn ₂ 0 ₄ , LiCo0 ₂ , LiV ₂ 0 ₅ or LiNiO ₂ can be described. These compounds react reversibly with compounds that can incorporate lithium ions into their lattice, such as graphite, to expand the lithium ions from the crystal lattice, in which the metal ions such as manganese, cobalt or nickel ions are oxidized. This reaction can be used in an electrochemical cell to store electricity by separating the compound which absorbs lithium ions, i.e. the anode material, and the mixed oxide containing lithium, i.e. the cathode material, by means of an electrolyte through which the lithium ions migrate from the mixed oxide into the anode material (charging process ).

The compounds suitable for the reversible storage of lithium ions are usually fixed on discharge electrodes by means of a binder.

When the cell is charged, electrons flow through an external voltage source and lithium cations through the electrolyte to the anode material. When the cell is used, the lithium cations flow through the electrolyte, while the electrons flow through a useful resistance from the anode material to the cathode material.

To avoid a short circuit within the electrochemical cell, there is an electrically insulating layer that is continuous for lithium cations between the two electrodes. This can be a so-called solid electrolyte or an ordinary separator.

As is known, solid electrolytes and separators consist of a carrier material into which a dissociable compound containing lithium cations to increase the lithium ion conductivity and usually other additives such as solvents are incorporated. US-A 5296318 and US-A 5429891 propose a copolymer of vinylidene difluoride and hexafluoropropene as the carrier material. However, the use of such highly resistant (co) polymers has a number of disadvantages.

Such polymers are not only expensive, but are also difficult to dissolve. Furthermore, due to their comparatively low lithium cation conductivity, they increase the resistance of the cell, so that the electrolyte, which usually consists of a compound containing lithium cations, such as LiPF ₆ , LiAsF ₆ or LiSbF ₆ and an organic solvent, is already in the manufacture of the insulating layer There is ethylene carbonate or propylene carbonate to add (US-A 5296318, US-A 5429891). In addition, such polymers can only be processed with, for example, high proportions of plasticizers, for example di-n-butyl phthalate, and of pyrogenic silicas, which are added in order to ensure adequate filming and cohesion of the electrolyte layer and the ability to be bonded to the electrode layers and adequate conductivity and to ensure permeability to lithium cations. The plasticizer must then be removed quantitatively from the layer composite of anode, solid electrolyte or separator layer and cathode layer by an extremely difficult and expensive extraction step before starting the batteries.

Solid electrolytes based on polyalkylene oxides are also known and are described, for example, in EP-A 559 317, EP-A 576 686, EP-A 537 930, EP-A 585 072 and US Pat. No. 5,279,910. The polyethers described there have been modified at the end or functional groups, for example by (meth) acryloyl groups, and are crosslinked before use as a solid electrolyte by supplying energy (heat, light). They also generally contain a conductive salt, eg LiPF ₆ , to improve their conductivity. speed. The use of a solid to improve the mechanical, thermal and electrical strength of the solid electrolyte is not described there. Accordingly, the systems described there - despite crosslinking - do not always have satisfactory properties with regard to the mechanical strength, the porosity of the films obtained and the short-circuit strength.

The object of the present invention is therefore to remedy the disadvantages mentioned and to provide a mixture which is particularly suitable for the production of solid electrolytes and separators, but is also used in the production of electrodes in electrochemical cells and for other applications described herein can be.

Due in particular to the presence of a solid III, as defined below, the use of the mixture according to the invention leads to solid electrolytes, separators or electrodes which, compared to the systems known hitherto, have an improved short-circuit strength, an increased pressure resistance, in particular at elevated temperatures above 120 ° C, as well as have a larger porosity, and are also able to sustainably suppress the formation of Li dendrites. The presence of the solid also results in improved cycle stability and a higher current carrying capacity of an electrochemical cell. When using the preferably used basic solids, the acid formed during the operation of an electrochemical cell is also trapped or neutralized.

Accordingly, in one embodiment, the present invention relates to a mixture Ia comprising a mixture Ila consisting of a) 1 to 95% by weight of a Li-ion-conducting solid III, preferably a basic Li-ion-conducting solid III with a primary particle size of 5 nm to 20 μm and

b) 5 to 99% by weight of a polymeric mass IV, obtainable by

Polymerization of

b l) 5 to 100% by weight based on the mass IV of a condensation product V from) at least one compound VI which is capable of having a

Carboxylic acid or a sulfonic acid or a derivative or a mixture of two or more thereof, and β) at least 1 mol per mole of compound VI of a carboxylic acid or sulfonic acid VII which has at least one free-radically polymerizable functional group, or one

Derivative thereof or a mixture of two or more thereof

and

b2) 0 to 95% by weight, based on the mass IV, of a further compound VIII with an average molecular weight (number average) of at least 5,000 with polyether segments in the main or side chain,

wherein the weight fraction of the mixture Ila in the mixture la is 1 to 100% by weight.

The above mixture la is preferably a mixture comprising a mixture Ila consisting of a) 1 to 95 wt .-% of a Li-ion conductive solid III, preferably a basic Li-ion conductive solid III, with a primary particle size of 5 nm to 20 microns and

b) 5 to 99% by weight of a polymeric mass IV, obtainable by polymerizing

bl) 5 to 100 wt .-% based on the mass IV of a condensation product V.

a) a polyhydric alcohol VI which contains carbon and oxygen atoms in the main chain,

and

β) at least 1 mole per mole of the polyhydric alcohol VI of an α, / S-unsaturated carboxylic acid VII,

and

b2) 0 to 95% by weight, based on the mass IV, of a further compound VIII with an average molecular weight (number average) of at least 5000 with polyether segments in the main or side chain,

In a further embodiment, the present invention relates to a mixture Ib containing a mixture IIb consisting of a) 1 to 95% by weight of a Li-ion-conducting solid III, preferably a basic Li-ion-conducting solid III, with a primary particle size of 5 nm to 20 μm and

b) 5 to 99 wt .-% of a polymer IX, obtainable by polymerization of

bl) 5 to 75% by weight, based on polymer IX, of an unsaturated compound X capable of free-radical polymerization, which is different from the above carboxylic acid or sulfonic acid VII or a derivative thereof, or a mixture of two or more thereof

and b2) 25 to 95% by weight, based on the polymer IX, of a further compound VIII with an average molecular weight (number average) of at least 5,000 with polyether segments in the main or side chain,

wherein the proportion by weight of the mixture Ilb in the mixture Ib is 1 to 100% by weight.

According to the invention, the solid III used is preferably inorganic Li-ion-conducting solids, more preferably an inorganic basic Li-ion-conducting solid, these solids preferably being selected from a Li-aluminate, a Li-aluminiosilicate, a Li-amide, a Li Borate, a Li carbonate, a Li carbide, a Li imide, a Li nitride, a Li oxide, a Li phosphate, a Li silicate, a Li sulfate, a Li zeolite and a mixture of two or more of them.

Examples include: lithium borates, such as Li ₄ B ₆ O _n * xH ₂ O, Li ₃ (BO ₂ ) ₃ , Li ₂ B ₄ O ₇ * xH ₂ O, LiBO ₂ , where x is a number from 0 to Can be 20; Lithium aluminates, such as Li ₉ 0 * A1 ₇ 0 ₃ * H ₉ 0, Li, Al ₉ O ₄ , LiA10 ₂ ; Lithium aluminosilicates, such as, for example, lithium-containing zeolites, feldspar, feldspar representatives, phyllo and inosilicates, and in particular LiAl- Si ₂ 0 ₆ (spodumene), LiAlSi ₄ O ₁₀ (petullite), LiAlSi0 ₄ (eucryptite), mica, such as K [Li, Al] ₃ [AlSi] ₄ O ₁₀ (F-OH) ₂ JK [Li, Al, Fe] ₃ | AlSi] ₄ O ₁ (F-OH) ₂ ; Lithium zeolites, in particular those in the form of fibers, sheets or cubes, in particular those having the general formula Li _{2 / z} O * A1 ₂ 0 ₃ * xSiO ₂ * yH ₂ O where z corresponds to the valence, x 1.8 to about 12 and y is 0 to about 8; Lithium carbides such as Li C ₉ , Li ₄ C; Li ₃ N; Lithium oxides and mixed oxides, such as LiA10 ₂ , Li ₂ MnO ₃ , Li ₂ O, Li ₂ 0 ₂ , Li ₂ MnO ₄ , Li ₂ TiO ₃ ; Li ₂ NH; LiNH ₂ ; Lithium phosphates, such as Li ₃ P0 ₄ , LiP0 ₃ , LiAlFP0 ₄ , Li-Al (OH) P0 ₄ , LiFeP0 ₄ , LiMnP0 ₄ ; Li ₂ CO ₃ ; Lithium silicates in the form of conductors, chains, layers and scaffolds, such as Li ₂ SiO ₃ , Li ₂ SiO ₄ and Li ₆ Si ₂ ; Lithium sulfates, such as Li ₂ SO ₄ , LiHSO ₄ , LiKSO ₄ ; the Li compounds mentioned in the discussion of the cathode compound, the presence of conductive carbon black in the mixture being excluded when used as solid III; and mixtures of two or more of the above-mentioned Li-ion-conducting solids.

Basic solids are particularly suitable. Basic solids are to be understood to mean those whose mixture with a liquid, water-containing diluent, which itself has a pH of at most 7, has a higher pH than this diluent.

The solids should advantageously be largely insoluble in the liquid used as the electrolyte and be electrochemically inert in the battery medium. Solids which have a primary particle size of 5 nm to 20 μm, preferably 0.01 to 10 μm and in particular 0.1 to 5 μm are particularly suitable, the specified particle sizes being determined by electron microscopy. The melting point of the solids is preferably above the operating temperature customary for the electrochemical cell, melting points above 120 ° C., in particular above 150 ° C., having proven particularly favorable.

The solids can be symmetrical with respect to their outer shape, i.e. have a size ratio of height: width: length (aspect ratio) of approximately 1 and as spheres, granules, approximately round structures, but also in the form of any polyhedra, such as present as a cuboid, tetrahedron, hexahedron, octahedron or as a bipyramid, or be distorted or asymmetrical, i.e. have a size ratio of height: width: length (aspect ratio) of not equal to 1 and e.g. present as needles, asymmetrical tetrahedra, asymmetrical bipyramids, asymmetrical hexahedron or octahedron, platelets, disks or as fibrous structures. If the solids are in the form of asymmetrical particles, the upper limit for the primary particle size given above relates to the smallest axis in each case.

In principle, all compounds which meet this criterion can be used as compound VI, which is capable of reacting with a carboxylic acid or a sulfonic acid VII or a derivative or a mixture of two or more thereof.

Compound VI is preferably selected from the group consisting of a mono- or polyhydric alcohol which has only carbon atoms in the main chain; a mono- or polyhydric alcohol which has at least one carbon atom in the main chain in addition to at least two Has an atom selected from the group consisting of oxygen, phosphorus and nitrogen; a silicon containing compound; an amine having at least one primary amino group: an amine having at least one secondary amino group; an amino alcohol; a mono- or polyvalent thiol; a compound having at least one thiol and at least one hydroxyl group; and a mixture of two or more of them.

Among these, compounds VI are preferred which have two or more functional groups which can react with the carboxylic acid or sulfonic acid.

When using compounds VI which contain amino groups as the functional group, it is preferred to use those with secondary amino groups, so that after the condensation / crosslinking either no or only small amounts of free NH groups are present in the mixture 1a are.

In particular, the following may be mentioned as preferred compounds: monohydric or polyhydric alcohols which have only carbon atoms in the main chain, with 1 to 20, preferably 2 to 20 and in particular 2 to 10 alcoholic OH groups, in particular di-, tri- and tetravalent - Ge alcohols, preferably having 2 to 20 carbon atoms, such as ethylene glycol, propane-1, 2- or -1, 3-diol, butane-1, 2- or -1, 3-diol, butene-1, 4th - Butin-l, 4-diol, hexane-l, 6-diol, neopentyl glycol, dodecane-l, 2-diol, glycerol, trimethylolpropane, pentaerythritol or sugar alcohols, hydroquinone, novolak, bisphenol A, but also, as from the above Definition is clear, monohydric alcohols, such as methanol, ethanol, propanol, n-, sec- or tert-butanol, etc. can be used; also can Polyhydroxyolefins, preferably those with two terminal hydroxyl groups, such as, for example, α, ω-dihydroxybutadiene, can be used; Polyester polyols, as are known, for example, from Ulimann's Encyclopedia of Industrial Chemistry, 4th edition, vol. 19, pp. 62-65 and are obtained, for example, by reacting dihydric alcohols with polyhydric, preferably dihydric, polycarboxylic acids; monohydric or polyhydric alcohols which contain at least one oxygen atom in the main chain in addition to at least two carbon atoms, preferably polyether alcohols, such as, for example, polymerization products of alkylene epoxides, for example isobutylene oxide, propylene oxide, ethylene oxide, 1, 2-epoxybutane, 1, 2-epoxypentane, 1, 2 Epoxyhexane, tetrahydrofuran, styrene oxide, it also being possible to use polyether alcohols modified at the end groups, such as polyether alcohols modified with NH ₉ end groups; these alcohols preferably have a molecular weight (number average) from 100 to 5000, more preferably 200 to 1000, and especially 300 to 800: such compounds are known per se and, for example, under the trademarks Pluriol ^® or Pluronic ^® (BASF Aktiengesellschaft) commercially available; Alcohols, as defined above, in which some or all of the carbon atoms have been replaced by silicon, in particular polysiloxanes or alkylene oxide / siloxane copolymers or mixtures of polyether alcohols and polysiloxanes, as described, for example, in EP-B 581 296 and EP-A 525 728 can be used, the statements made above also relating to the molecular weight of these alcohols; Alcohols as defined above, in particular polyether alcohols in which some or all of the oxygen atoms have been replaced by sulfur atoms, the statements made above also relating to the molecular weight of these alcohols; monohydric or polyhydric alcohols which contain at least one phosphorus atom or at least one nitrogen atom in the main chain in addition to at least two carbon atoms, such as, for example, diethanolamine and triethanolamine; Lactones derived from compounds of the general formula HO- (CH ₉ ) _z - COOH, where z is a number from 1 to 20, such as e-caprolactone, j6-propiolactone, γ-butyrolactone or methyl-e- caprolactone; a silicon-containing compound such as di- or trichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, dimethylvinylchlorosilane; Silanols, such as trimethylsilanol; an amine having at least one primary and / or secondary amino group, such as, for example, butylamine, 2-ethylhexylamine, ethylene diamine, hexamethylene diamine, diethylene triamine, tetraethylene pentamine, pentaethylene hexamine, aniline, phenylene diamine;

Polyether diamines, e.g. 4,7-dioxydecane-l, 10-diamine, 4, 1 1-dioxytetradecan-l, 14-diamine; a mono- or polyvalent thiol, e.g. aliphatic thiols, e.g.

Methanethiol, ethanethiol, cyclohexanethiol, dodecanethiol; aromatic thiols such as thiophenol, 4-chlorothiophenol, 2-mercaptoaniline; a compound with at least one thiol and at least one hydroxyl group, such as 4-hydroxythiophenol and monothio derivatives of the polyhydric alcohols defined above; Amino alcohols, such as ethanolamine, N-methylethanolamine, N-ethylethanolamine, N-butylethanolamine, 2-amino-l-propanol, 2-amino-l-phenylethanol, mono- or polyaminopolyols with more than two aliphatically bound hydroxyl groups such as tris (hydroxymethyl) methylamine, glucamine, N, N ^X bis (2-hydroxyethyl) ethylenediamine.

Mixtures of two or more of the compounds VI defined above can also be used.

According to the invention, the compounds VI mentioned above are treated with a

Carboxylic acid or sulfonic acid VII, which has at least one radically polymerizable functional group, or a derivative thereof or a A mixture of two or more of them is condensed, at least one, preferably all, of the free groups capable of condensation within the compounds VI being condensed with the compound VII.

In principle, all carboxylic and sulfonic acids which have at least one free-radically polymerizable functional group and their derivatives can be used as carboxylic acid or sulfonic acid VII in the context of the present invention. The term "derivatives" used here encompasses both compounds which are derived from a carboxylic or sulfonic acid which is modified on the acid function, such as e.g. Esters, acid halides or acid anhydrides, as well as compounds derived from a carbon or sulfonic acid modified on the carbon skeleton of the carbon or sulfonic acid, e.g. Halogen carbon or sulfonic acids.

The following are particularly to be mentioned as compound VII: α, ß-unsaturated carboxylic acids or / 3,7-unsaturated carboxylic acids.

Particularly suitable α.ß-unsaturated carboxylic acids are those of the formula

in which R ¹ , R ² and R ^{3 represent} hydrogen or C _r to C ₄ alkyl radicals, acrylic acid and methacrylic acid being preferred among these; cinnamic acid, maleic acid, fumaric acid, itaconic acid, or p-vinylbenzoic acid, and derivatives thereof, such as, for example, anhydrides, such as, for example, maleic or itaconic anhydride;

Halides, in particular chlorides, such as, for example, acrylic or methacrylic acid chloride; Esters, such as (cyclo) alkyl (meth) acrylates with up to 20 carbon atoms in the alkyl radical, such as methyl, ethyl, propyl, butyl, hexyl, 2-ethylhexyl, stearyl, lauryl, Cyclohexyl, benzyl, trifluoromethyl, hexafluoropropyl, tetrafluoropropyl (meth) acrylate, polypropylene glycol mono (meth) acrylates, polyethylene glycol mono (meth) acrylates, poly (meth) acrylates of polyhydric alcohols, such as, for example, glycerol di (meth) acrylate, trimethylol propane -di (meth) acrylate, pentaerythritol di- or tri (meth) acrylate, diethylene glycol bis (mono- (2-acryloxy) ethyl) carbonate, poly (meth) acrylates of alcohols, which in turn have a radical-polymerizable group , such as esters of (meth) acrylic acid and vinyl and / or allyl alcohol;

Vinyl esters of other aliphatic or aromatic carboxylic acids, such as. B. vinyl acetate, vinyl propionate, vinyl butyrate, vinyl hexanoate, vinyl octanoate, vinyl decanoate, vinyl stearate, vinyl palminate, vinyl crotonoate, divinyl adipate, divinyl sebacate, vinyl 2-ethylhexanoate, vinyl trifluoroacetate; Allyl esters of other aliphatic or aromatic carboxylic acids, such as. As allyl acetate, allyl propionate, allyl butyrate, allyl hexanoate, Allyloctanoat, allyl decanoate, allyl stearate, Allylpalminat, Allylcrotonoat, Allylsalicylat, allyl lactate, diallyl oxalate, diallyl malonate, diallyl succinate and allyl, Diallylglutarat, diallyl adipate, Diallylpimelat, Diallylcinnanmat, diallyl maleate, diallyl phthalate, diallyl isophthalate, triallyl benzene -l, 3,5-tricarboxylate, diallylcinnatricarboxylate, allyl trifluoroacetate, allyl perfluorobutyrate, allyl perfluorooctanoate; jß, γ-unsaturated carboxylic acids or their derivatives, such as. B. vinyl acetic acid, 2-methyl vinyl acetic acid, isobutyl 3-butenoate, allyl 3-butenoate, allyl 2-hydroxy-3-butenoate, diketene; Sulfonic acids, e.g. Vinylsulfonic acid, allyl and methallylsulfonic acid, and their esters and halides, vinyl benzenesulfonic acid ester, 4-vinylbenzenesulfonic acid amide.

Mixtures of two or more of the carboxylic and / or sulfonic acids described above can also be used. Compounds X which can be used for free-radical polymerization and which can be used for the preparation of the polymer IX are as follows: olefinic hydrocarbons, such as ethylene, propylene, butylene. Isobutene, hexene or higher homologues and vinylcyclohexane; (Meth) acrylonitrile; halogen-containing olefinic compounds, such as vinylidene fluoride, vinylidene chloride, vinyl fluoride, vinyl chloride, hexafluoropropene, trifluoropropene. 1,2-dichloroethylene, 1,2-difluoroethylene and tetrafluoroethylene; Vinyl alcohol, vinyl acetate, N-vinyl pyrrolidone, N-vinyl imidazole, vinyl formamide;

Phosphorus nitride chlorides, e.g. Phosphorus dichloride nitride, hexachlor (tri-phosphazene), and their derivatives which are partially or completely substituted by alkoxy, phenoxy, amino and fluoroalkoxy groups, i.e. Compounds that can be polymerized to polyphosphazenes; aromatic, olefinic compounds such as e.g. Styrene, α-methylstyrene;

Vinyl ethers such as Methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, decyl, dodecyl, 2-ethylhexyl, cyclohexyl, benzyl, trifluoromethyl, hexafluoropropyl, tetrafluoropropyl vinyl ether.

Mixtures of the above compounds X can of course also be used, in which case copolymers are formed which, depending on the type of preparation, contain the monomers in a statistically distributed manner or give block copolymers.

These compounds X, as well as the condensation products V, are polymerized in a conventional manner, which is well known to the person skilled in the art, preferably free-radically polymerized, with regard to the molecular weights obtained what has been said hereinafter regarding compound VIII. Compounds VIII are primarily compounds with an average molecular weight (number average) of at least 5,000, preferably 5,000 to 20,000,000, in particular 100,000 to 6,000,000, which are capable of solvating lithium cations and functioning as binders . Suitable compounds VIII are, for example, polyethers and copolymers which have at least 30% by weight of the following structural unit, based on the total weight of compound VIII:

where R ¹ , R ² , R ³ and R ^{4 represent} aryl groups, alkyl groups, preferably methyl groups, or hydrogen, may be the same or different and may contain heteroatoms such as oxygen, nitrogen, sulfur or silicon.

Such connections are for example in: M. B. Armand et. al. , Fast Ion Transport in Solids, Elsevier, New York, 1979, pp. 131-136, or in FR-A 7832976.

Compound VIII can also consist of mixtures of two or more such compounds.

The polymer mass IV or polymer IX defined above can also be in the form of a foam, in which case the solid II is present as such distributed therein.

According to the invention, the mixtures Ila should contain 1 to 95% by weight, preferably 25 to 90% by weight and in particular 30 to 70% by weight, of one Solids III and 5 to 99% by weight, preferably 10 to 75% by weight and in particular 30 to 70% by weight, consist of a polymeric mass IV, the compound VIII of the polymeric mass IV advantageously having an average molecular weight (number average) from 5,000 to 100,000,000, preferably 5 to 50,000 to 8,000,000. The polymeric mass IV can be converted by reaction of 5 to 100% by weight, preferably 30 to 70% by weight, based on the polymeric mass IV of a compound V and 0 to 95% by weight, in particular 30 to 70% by weight. based on the polymeric mass IV of a compound VIII can be obtained.

10

According to the invention, the mixtures IIb should contain 1 to 95% by weight, preferably 25 to 90% by weight, and in particular 30 to 70% by weight, of a solid III and 5 to 99% by weight, preferably 10 to 75 % By weight and in particular 30 to 70% by weight consist of a polymer IX, wherein compound VIII of polymer IX should advantageously have an average molecular weight (number average) of 5,000 to 100,000,000, preferably 50,000 to 8,000,000 . The polymer IX can be converted by reaction of 5 to 75% by weight, preferably 30 to 70% by weight, based on the polymer IX of a compound X and 25 to 95% by weight, in particular 30 to 70%

20% by weight, based on the polymer IX of a compound VIII, can be obtained.

In the following the mixtures la and Ib according to the invention or the mixtures Ila and Ilb are discussed together and referred to as "mixture according to the invention" or "mixture according to the invention".

To produce the mixture according to the invention, which is an inventive

Mixture in amounts of 1 to 100% by weight, preferably 35 to 100

% By weight and in particular 30 to 70% by weight, based on the

30 should contain appropriate mixture, a mixture of a solid III, a condensation product V, optionally a compound VIII, or a mixture of a solid III, a compound X and a compound VIII and conventional additives such as plasticizers, preferably plasticizers containing polyethylene oxide or polypropylene oxide, plasticizers.

Aprotic solvents, preferably those which solvate Li ions, such as, for example, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, ethylene carbonate, propylene carbonate; Oligoalkylene oxides, such as, for example, dibutyl ether, di-tert-butyl ether, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, dinonyl ether, didecyl ether, didodecyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, 1-tert.-butoxy-2-methoxyethane, 1-tert. -Butoxy-2-ethoxyethane, 1, 2-dimethoxypropane, 2-methoxyethyl ether, 2-ethoxyethyl ether, diethylene glycol dibutyl ether, dimethylene glycol tert-butyl methyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, γ-butyrolactone, dimethylformamide; Hydrocarbons of the general formula C _n H _{2n + 2} with 7 <n <50; organic phosphorus compounds, in particular phosphates and phosphonates, such as trimethyl phosphate, triethyl phosphate, tripropyl phosphate, triisobutyl phosphate, tripentyl phosphate, trihexyl phosphate, tris (2-ethylhexyl) phosphate, tridecyl phosphate, diethyl phosphate, diethyl Tris (2-methoxyethyl) phosphate, tris (tetrahydrofuran l) phosphate, tris (1 H, 1 H, 5H-octafiuorpenty phosphate, tris (1 H, 1 H-tr ifl uorethyl) phosphate, tris (2- (diethylamino) ethyl) phosphate, dietropylpropylphosphonate, dibutylbutylphosphonate, dihexylhexylphosphonate, dioctyloctylphosphonate, methyldiethylphosphonoethyl (oxyethyl), , Ethyl diethoxylphosphinyl formate, trimethylphosphonoacetate, triethylphosphonoacetate, tripropylphosphonoacetate, tributylphosphonoacetate; organic sulfur compounds Bonds, such as sulfates, sulfonates, sulfoxides, sulfones and sulfites, such as dimethyl sulfite, diethyl sulfite, glycol sulfite, dimethyl sulfone, diethyl sulfone, diethyl propyl sulfone, dibutyl sulfone, tetramethylene sulfone, methyl sulfulfate, ethyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfoxide, diphenyl sulfonate, , 4-butanediol bis (methanesulfonate), diethyl sulfate, dipropyl sulfate, dibutyl sulfate, dihexyl sulfate, dioctyl sulfate, SO ₉ ClF; Nitriles, such as acrylonitrile; Dispersants, in particular with a surfactant structure; and mixtures thereof are used.

The mixtures according to the invention can be dissolved or dispersed in an inorganic, preferably an organic liquid diluent, the mixture according to the invention preferably having a viscosity of 100 to 50,000 mPas, and then in a manner known per se, such as spray coating, pouring, dipping, Spin coating, roller coating, printing in high, low or flat printing or screen printing, can be applied to a carrier material. Further processing can be carried out as usual, e.g. by removing the diluent and curing the mixture.

Suitable organic diluents are aliphatic ethers, in particular tetrahydrofuran and dioxane, hydrocarbons, in particular hydrocarbon mixtures such as gasoline, toluene and xylene, aliphatic esters, in particular ethyl acetate and butyl acetate and ketones, in particular acetone, ethyl methyl ketone and cyclohexanone. Combinations of such diluents can also be used.

The materials usually used for electrodes, preferably metals such as aluminum and copper, come into consideration as carrier material. Temporary intermediate carriers, such as films, in particular polyester films, such as polyethylene terephthalate films, can also be used. Such films can advantageously be provided with a separating layer, preferably made of polysiloxanes.

The solid electrolytes and separators can also be produced thermoplastically, for example by injection molding, melt molding, pressing, kneading or extruding, if appropriate with a subsequent calendering step of the mixture according to the invention.

After the mixture according to the invention has formed a film, volatile components, such as solvents or plasticizers, can be removed.

The mixture according to the invention can be crosslinked in a manner known per se, for example by irradiation with ionic or ionizing radiation, electron beam, preferably with an acceleration voltage between 20 and 2,000 kV and a radiation dose between 5 and 50 Mrad, UV or visible light, wherein in Usually, an initiator such as benzil dimethyl ketal or 1,3,5-trimethylbenzoyltriphenylphosphine oxide is advantageously added in amounts of in particular at most 1% by weight, based on the polymer composition IV or the polymer IX, and the crosslinking is generally within 0.5 up to 15 minutes can advantageously be carried out under inert gas such as nitrogen or argon; by thermal radical polymerization, preferably at temperatures above 60 ° C., an initiator such as azo-bis-isobutyronitrile being advantageously obtained in amounts of generally at most 5% by weight, preferably 0.05 to 1% by weight can add to the polymeric mass IV or the polymer IX; by electrochemically induced polymerization; or by ionic polymerization, for example by acid-catalyzed cationic polymerization, the primary catalyst Acids, preferably Lewis acids such as BF ₃ , or in particular LiBF ₄ or LiPF ₆ are suitable. Catalysts containing lithium ions such as LiBF ₄ or LiPF ₆ can advantageously remain in the solid electrolyte or separator as the conductive salt.

If the mixture according to the invention is to be used as a solid electrolyte or separator in an electrochemical cell, a dissociable compound containing lithium cations, a so-called conductive salt, and possibly further additives, such as in particular organic solvents, a so-called electrolyte, are incorporated.

Some or all of these substances can be added to the mixture during the production of the layer or introduced into the layer after the layer has been produced.

The generally known conductive salts, described for example in EP-A 0 096 629, can be used as conductive salts. LiPF ₆ , LiBF ₄ , LiClO ₄ , LiAsF ₆ , ÜCF ₃ SO ₃ , LiC (CF ₃ SO ₂ ) ₃ , LiN (CF ₃ SO ₂ ) ₂ , Li (C _n F _{2n + 1} ) SO ₃ are preferred according to the invention , LiC [(C _n F _{2n + 1} ) SO ₂ ] ₃ , LiN (C _n F _{2n + 1} S0 ₂ ) ₉ , each with n = 2 to 20, LiN (SO ₉ F) ₉ , LiAlCl ₄ , LiSiF ₆ , LiSbF ₆ or a mixture of two or more thereof, wherein LiBF ₄ and LiPF ₆ are preferably used as the conductive salt.

These conductive salts are used in amounts of 0.1 to 50% by weight, preferably 0.1 to 20% by weight, in particular 1 to 10% by weight, based in each case on the mixture according to the invention.

Suitable organic electrolytes are the compounds discussed above under "plasticizers", preferably the customary organic see electrolytes, preferably esters such as ethylene carbonate, propylene carbonate, dimethyl carbonate and diethyl carbonate or mixtures of such compounds are used.

Solid electrolytes, separators and / or electrodes according to the invention suitable for electrochemical cells should advantageously have a thickness of 5 to 500 μm, preferably 10 to 500 μm, more preferably 10 to 200 μm and in particular 20 to 100 μm.

If the mixture according to the invention is to be used as or for producing a cathode, an electron-conducting, electrochemically active compound (cathode compound), preferably a lithium compound, conventionally used for cathodes is incorporated. To be mentioned in particular: LiCo0 ₂ , LiNiO ₂ , LiNi _x Co _y O ₂ , LiNi _χ Co _y Al _z 0 ₉ , with 0 <x, y, z <l, LixMnO ₂ (0 <x <l), Li _χ Mn ₉ O ₄ (0 <x <2), Li _χ MoO ₂ (0 <x <2), Li _χ MnO ₃ (0 <x <l), Li _x Mn0 ₉ (0 <x <2), Li _χ Mn ₉ O ₄ (0 <x <2), Li _χ V ₉ 0 ₄ (0 <x <2.5), Li _χ V ₂ O ₃ (0 <x <3.5), Li _x VO ₂ (0 <x < l), Li _x W0 ₉ (0 <x <l), Li _x W0 ₃ (0 <x <l), Li _x TiO ₂ (0 <x≤l), Li _χ Ti ₂ O ₄ (0 <x < 2), Li _x RuO ₂ (0 <x <l), Li _x Fe ₂ O ₃ (0 <x <2), Li _χ Fe ₃ 0 ₄ (0 <x <2), Li _χ Cr ₉ 0 ₃ ( 0 <x <3), Li _χ Cr ₃ 0 ₄ (0 <x <3.8), Li _x V ₃ S ₅ (0 <x <1.8), Li _x Ta ₂ S ₂ (0 <x≤l), Li _x FeS (0 <x≤l), Li _χ FeS ₂ (0 <x <l), Li _x NbS ₂ (0 <x <2.4), Li _x MoS ₂ (0 <x <3), Li _x TiS ₂ (0 <x <2), Li _x ZrS ₂ (0 <x <2), Li _χ NbSe ₂ (0 <x <3), Li _x VSe ₂ (0 <x <l), Li _x NiPS ₂ (0 <x <l, .5), Li _χ FePS ₂ (0 <x <1.5).

When used as an anode, a conventional electron-conducting electrochemically active compound (anode connection) known from the prior art is incorporated as anode material, the following in particular being mentioned: Lithium, lithium-containing metal alloys, micronized carbon black, natural and synthetic graphite, synthetically graphitized coal dust and carbon fibers, oxides such as titanium oxide, zinc oxide, tin oxide, molybdenum oxide, tungsten oxide, carbonates such as titanium carbonate, molybdenum carbonate, and zinc carbonate.

When used to produce or as an anode, up to 20% by weight, based on the total weight of the mixture, of conductive carbon black and, if appropriate, the customary additives mentioned above are added to the mixture according to the invention. When used for the production of or as a cathode, the mixture contains, based on its total weight, 0.1 to 20% by weight of conductive carbon black.

The mixtures according to the invention can be used in electrochemical cells as the sole solid electrolyte and / or separator and / or electrode or in a mixture with other solid electrolytes, separators and / or electrodes.

Furthermore, the present invention relates to a composite body which can be used in particular in electrochemical cells, preferably in the form of a film, more preferably in the form of a film with a total thickness of 15 to 1500 μm, in particular with a total thickness of 50 to 500 μm, comprising at least a first layer, which contains an electron-conducting, electrochemically active compound, and at least one second layer, which contains the mixture according to the invention defined above and is free of an electron-conducting, electrochemically active compound.

The present invention further describes a method for producing such a composite body, which comprises the following steps:

(I) making at least a first layer as defined above; (II) making at least a second layer as defined above; and

(III) then bringing the at least one first layer together with the at least one second layer by a conventional coating process.

The at least one second layer is preferably produced on a temporary carrier. Temporary carriers usually used according to the invention, such as e.g. a release film made of a polymer or a preferably coated paper, e.g. a siliconized polyester film can be used. However, the production of this second layer is also on a permanent support, e.g. an arrester electrode or even completely without a carrier.

The layers defined above are brought together or produced by pressureless processes for coating or producing foils, such as Casting or knife coating, as well as by processing methods under pressure, e.g. Extruding, laminating, laminating, calendering or pressing. If necessary, the composite body produced in this way can be crosslinked or hardened by radiation, electrochemically or thermally.

Of course, in addition to the second layer defined above, the first layer defined above can also contain the mixture according to the invention.

As can be seen from the above, it is thus readily possible to provide a composite body with the components separating film / separator (second layer) / electrode (first layer).

Furthermore, it is possible to provide a composite body with the components anode / separator / cathode by double-sided coating. Here is an example:

First, an anode material, for example tin oxide, conductive carbon black, the mixture according to the invention, a conductive salt and a plasticizer, for example propylene carbonate, are mixed with one another and the resulting mixture is poured onto an electrode and then irradiated with UV light (component 1). Subsequently, a cathode material, for example LiMn ₂ O ₄ , is placed on a conductive electrode coated with conductive carbon black and a mixture of the mixture according to the invention, a conductive salt and a plasticizer is poured onto it. This composite is also subsequently irradiated with UV light (component 2). By bringing the two components described above together, a composite body is obtained which can be used as an electrochemical cell in conjunction with any solid and / or liquid electrolyte.

A composite body anode / separator / cathode as described above can also be produced without the use of a carrier or the discharge electrodes, since the composite body obtained, consisting of a first and a second layer, as defined above, is in itself one for use in electrochemical cells has sufficient mechanical stability.

The filling of such composite bodies with an electrolyte and conductive salt can take place both before bringing the layers together, and preferably after the layers have been brought together, if necessary after contacting them with suitable discharge electrodes, for example a metal foil, and even after the composite body has been introduced into a battery housing, the special microporous structure of the layers when using the mixture according to the invention, in particular due to the presence of the solid defined above in the separator and possibly in the electrodes, the suction of the Electrolytes and the conductive salt and the displacement of the air in the pores. Filling can be carried out at temperatures from 0 ° C to approximately 100 ° C depending on the electrolyte used.

The electrochemical cells according to the invention can be used in particular as a car, device or flat battery.

As can be seen from the above, the present invention also relates to the use of the mixture according to the invention or of the composite body described above for producing a solid electrolyte, a separator, an electrode, in a sensor, an electrochromic window, a display, a capacitor or an ion-conducting film, and a solid electrolyte, a separator, an electrode, a sensor, an electrochromic window, a display, a capacitor or an ion-conducting film, each of which contains the mixture according to the invention or the composite body described above.

Furthermore, it relates to an electrochemical cell comprising a solid electrolyte, separator or an electrode, as defined above, or a combination of two or more thereof, and the use of the electrochemical cell defined above as a car battery, device battery or flat battery.

In addition, the present invention relates generally to the use of a solid III with a primary particle size of 5 nm to 20 μm in a solid electrolyte, a separator or an electrode to increase the cycle stability of electrochemical cells, since it was found out when the present invention was completed has that the addition of such a solid has a very positive effect on this property of electrochemical cells. EXAMPLES

example 1

65 a g epoxysilane hydrophobic, wollastonite (Tremin ^® 800 EST, Quarzwerke Frechen) microns with a mean particle size of 3, the aqueous suspension having a pH value of 8.5, and 10 g of Li ₂ CO ₃ was mixed with a high speed in 300 g of toluene dispersed. Subsequently, to the mixture 12.5 g of a polyethylene oxide having an average molecular weight (number average) of 2,000,000 (Polyox ^®, Union Carbide), 12.5 g of a Methacrylsäurediesters of a propylene oxide-ethylene oxide block polymer (Pluriol PE600 ^®, BASF Aktiengesellschaft) and 0.02 g of a UV-photoinitiator (Lucirin ^® BDK, BASF Aktiengesellschaft) were added.

The mixture was then applied to a siliconized release paper at 60 ° C. using a doctor blade with a casting gap of 300 μm, the diluent was removed within 5 minutes and, after the dried coating had been peeled off, an approximately 40 μm thick film was obtained, which was passed through 10 in an argon atmosphere minutes exposure at a distance of 5 cm under a field of superactin fluorescent tubes (TL 09, Philipps) was photocrosslinked.

The flexible film had excellent flexural strength. Bending radii well below 1 mm were tolerated without breaking.

Even after storage for more than two weeks at room temperature, the film showed no spherolite-like polyethylene oxide crystals and good swelling resistance in the organic electrolytes mentioned, which contain a conductive salt. The organic electrolytes containing a conductive salt were absorbed in sufficient quantity by spontaneous diffusion within a few minutes with a swelling in weight of less than 50% by weight.

The swollen film had good strength.

The results are summarized in the table.

Comparative Example 1

12.5 g of a polyethylene oxide having an average molecular weight (number average) of 2,000,000 (Polyox ^®, Union Carbide), 12.5 g of metha crylsäurediesters of a propylene oxide-ethylene oxide block polymer (Pluriol PE600 ^®, BASF Aktiengesellschaft) and 0.02 g of a UV-photoinitiator (Lucirin ^® BDK, BASF Aktiengesellschaft) were dissolved in 200 g THF.

The mixture was then applied to a siliconized release paper at 60 ° C. using a doctor blade with a casting gap of 750 μm, the thinner was removed within 5 minutes and, after the dried coating had been peeled off, an approximately 40 μm thick film was obtained, which was under an argon atmosphere was crosslinked by exposure for 10 minutes at a distance of 5 cm under a field of superactinic fluorescent tubes (TL 09, Philipps).

The flexible film had excellent flexural strength. Bending radii well below 1 mm were tolerated without breaking. Even after storage for more than two weeks at room temperature, the film showed no spherulite-like polyethylene oxide crystals and a satisfactory swelling resistance in the organic electrolytes mentioned, which contain a conductive salt. The organic electrolytes containing a conductive salt were absorbed in sufficient quantity by spontaneous diffusion within a few minutes with a swelling in the weight of less than 150% by weight, with a considerable change in the size and thickness of the film.

The strength was significantly lower than in Examples 1 to 3.

In lithium ion batteries, the film consistently led to cell failure due to excessive self-discharge rates or micro-short circuits.

The results are summarized in the table.

Comparative Example 2

75 g of an epoxysilane with hydrophobic ierten wollastonite (Tremin ^® 800 EST, Quarzwerke Frechen) microns with a mean particle size of 3, the aqueous suspension having a pH value of 8.5, was dispersed using a high speed in 300 g of toluene. Subsequently, to the mixture 12.5 g of a polyethylene oxide having an average molecular weight (number average) of 2,000,000 (Polyox ^®, Union Carbide), 12.5 g of a Methacrylsäurediesters of a propylene oxide-ethylene oxide block polymer (Pluriol PE600 ^®, BASF Aktiengesellschaft) and 0.02 g of a UV-photoinitiator (Lucirin ^® BDK, BASF Aktiengesellschaft) were added.

The mixture was then applied to a siliconized release paper at 60 ° C. using a doctor blade with a casting gap of 300 μm, the diluent was removed within 5 minutes and an approximately 40 μm thick film was obtained after the dried coating had been peeled off. The flexible film had excellent flexural strength. Bending radii well below 1 mm were tolerated without breaking.

After storage for more than two weeks at room temperature, the film showed small circular spherolite-like polyethylene oxide crystal zones and insufficient swelling resistance in the organic electrolytes mentioned, which contain a conductive salt. After just a few minutes of swelling, cracks appear or the film sticks together, so that the swollen film can no longer be handled.

The results are summarized in the table.

Comparative Example 3

According to US-A 5429891, Example 1 (F), were added to a mixture of 30 g of a vinylidene fluoride-hexafluoropropene copolymers (Kynarflex ^® 2822 company ELF-Atochem), 20 g of a silanized fumed silica (Aerosil R974, Degussa), whose aqueous suspension has a pH of 7, 50 g of dibutyl phthalate (Palatinol C, BASF Aktiengesellschaft) and 200 g of acetone 5% by weight, based on dibutyl phthalate, of trimethylolpropane trimethacrylate.

Then the mixture with a doctor blade with a gap of 750 microns was coated on a glass plate, immersed 15 minutes in a stream of air dried, and between 0.075 mm thick Mylar ^® layers. The 100 μm thick film layer was then crosslinked by irradiation with electrons having an energy of 4.5 MeV at a dose of 5 Mrad, with a dose of 2.5 Mrad being used per irradiation pass. The flexible film had good flexural strength.

Before the film was used in lithium-ion batteries, complex removal of the plasticizer by extraction from the film was necessary, since otherwise poor cycle stability is achieved by poisoning the electrodes. To remove the plasticizer, the film was extracted five times for 10 minutes with 50 times the film weight of diethyl ether at room temperature. After removing the plasticizer, the film is unstable and breaks easily when bent.

The plasticizer-free film showed good swelling resistance in the organic electrolytes containing a conductive salt.

A sufficient amount of the organic electrolytes containing a conductive salt was absorbed by spontaneous diffusion within a few minutes.

The swollen film had good strength.

The results are summarized in the following table.

9/19921

- 32

table

Grades: 1 very good 2 good

3 satisfactory

4 poor

5 bad

6 too bad, test not feasible

Claims

PATENT CLAIMS

1. Mixture la, comprising a mixture Ila, consisting of

a) 1 to 95% by weight of a Li-ion-conducting solid III, preferably a basic Li-ion-conducting solid III, with a primary particle size of 5 nm to 20 μm and

b) 5 to 99% by weight of a polymeric mass IV, obtainable by polymerizing

bl) 5 to 100% by weight based on the mass IV of a condensation product V from) at least one compound VI which is capable of reacting with a carboxylic acid or a sulfonic acid or a derivative or a mixture of two or more thereof, and iδ) at least 1 mole per mole of compound VI of a carboxylic acid or sulfonic acid VII which has at least one free-radically polymerizable functional group, or a derivative thereof or a mixture of two or more thereof

and

b2) 0 to 95% by weight, based on the mass IV, of a further compound VIII with an average molecular weight (number average) of at least 5,000 with polyether segments in the main or side chain, wherein the weight fraction of the mixture Ila in the mixture la is 1 to 100% by weight.

2. Mixture according to claim 1, wherein the compound VI is selected from the group consisting of a mono- or polyhydric alcohol which has only carbon atoms in the main chain; a monohydric or polyhydric alcohol which has at least one atom in the main chain in addition to at least two carbon atoms and is selected from the group consisting of oxygen, phosphorus and nitrogen; a silicon containing compound; an amine having at least one primary amino group; an amine having at least one secondary amino group; an amino alcohol; a mono- or polyvalent thiol; a compound having at least one thiol and at least one hydroxyl group; and a mixture of two or more of them.

3. Mixture according to claim 1 or 2, wherein the carbon or sulfonic acid VII or the derivative thereof is selected from the group consisting of an α, ^ -unsaturated carboxylic acid or a derivative thereof, a vinyl ester of an aliphatic or aromatic carboxylic acid, an allyl ester aliphatic or aromatic carboxylic acid, and a mixture of two or more thereof.

4. Mixture according to one of claims 1 to 3, wherein the mixture Ila from

a) 1 to 95% by weight of a Li-ion-conducting III, preferably a basic Li-ion-conducting solid III, with a primary particle size of 5 nm to 20 μm and b) 5 to 99 wt .-% of a polymeric mass IV, obtainable by polymerization of

bl) 5 to 100% by weight based on the mass IV of a condensation product ₅

) a polyhydric alcohol VI, which contains carbon and oxygen atoms in the main chain,

10 and

0) at least 1 mole per mole of the polyhydric alcohol VI of an α, / 3-unsaturated carboxylic acid VII,

ι ₅ and

25

5. Mixture Ib containing a mixture IIb consisting of

a) 1 to 95 wt .-% of a Li-ion conductive solid III, preferably a basic Li-ion conductive solid, with a primary particle size of 5 nm to 20 microns and b) 5 to 99 wt .-% of a polymer IX, obtainable by polymerization of

bl) 5 to 75% by weight based on the polymer IX

5 radical polymerization capable compound X, which is different from the carboxylic acid or sulfonic acid VII or a derivative thereof, or a mixture of two or more thereof

10 and

b2) 25 to 95% by weight, based on the polymer IX, of a further compound VIII with an average molecular weight (number average) of at least 5,000 with polyether segments in ₅ main or side chain,

wherein the weight fraction of the mixture Ilb in the mixture Ib is 1 to 100% by weight.

6. Mixture according to one of claims 1 to 5, wherein the Li-ion-conducting solid III is selected from a Li-aluminate, a Li-aluminiosilicate, a Li-amide, a Li-borate, a Li-carbonate, a Li Carbide, a Li imide, a Li nitride, a Li oxide, a Li phosphate, a Li silicate, a Li sulfate, a Li zeolite and

25 a mixture of two or more of them.

7. Composite body, comprising at least a first layer, which contains an electron-conducting, electrochemically active compound, and

30 at least one second layer, which is a mixture according to one of the Contains claims 1 to 6, and is free of an electron-conducting, electrochemically active compound.

8. Use of a mixture according to one of claims 1 to 6 or a composite body according to claim 7 for the production of a solid electrolyte, a separator, an electrode, in a sensor, an electrochromic window, a display, a capacitor or an ion-conducting film.

9. solid electrolyte, separator, electrode, sensor, electrochromic window, display, capacitor or ion-conducting film, each containing a mixture according to one of claims 1 to 6 or a composite body according to claim 7.

10. An electrochemical cell comprising a solid electrolyte, separator or an electrode according to claim 9 or a combination of two or more thereof.

11. A car battery, device battery or flat battery comprising an electromechanical cell according to claim 10.

12. Use of a Li-ion-conducting solid III with a primary particle size of 5 nm to 20 μm in a solid electrolyte, a separator or an electrode to increase the cycle stability of electrochemical cells.