MXPA01010115A - Composite bodies used as separators in electrochemical cells - Google Patents

Abstract

The invention relates to composite bodies having at least one first layer, containing a composition comprising (a) 1 to 99 percent by weight of a solid (I) with a primary particle size ranging from 5 nm to 100&mgr;m or a mixture consisting of at least two solids;(b) 99 to 1 percent by weight of a polymeric binder (II) obtained by polymerization of b1) 5 to 100 percent by weight, in relation to the binder (II), of a condensation product (III) consisting of (&agr;) at least one compound (IV) capable of reacting with a carboxylic acid or a sulphonic acid or a derivative or a mixture of two or more thereof and (&bgr;) at least one mole per mole of the compound (IV) consisting of a carboxylic acid or a sulphonic acid (V) having at least one radically polymerizable functional group or a derivative thereof or a mixture consisting of two or more thereof and b2) 0 to 95 percent by weight, in relation to the binder (II), of an additional compound (VII) having a mean molecular weight (numerical average) of at least 5000 with polyether segments in the main or side chain, wherein the at least one layer is applied on at least one second layer comprising at least one conventional separator.

Description

COMPOSITE BODIES USED AS SEPARATORS IN ELECTROCHEMICAL CELLS. The present invention relates to composite materials which are suitable in particular as electrochemical cell separators, preferably rechargeable cells and in particular lithium batteries and lithium ion batteries, these separators and, respectively, electrochemical cells by themselves, and also a process to produce these compounds. Electrochemical cells, in particular those that are rechargeable, are very well known, for example from the Encyclopedia of Industrial Chemistry of Ullmann, 5th ed., Vol.

A3, VCH Verlagsgesellschaft mbH, Weinheim 1985, pages 343-397. Due to their high density of specific energy storage, lithium batteries and lithium ion batteries occupy a particular position between these cells, especially as secondary cells. As described, inter alia, in the above extract from "Ullmann", such cells contain oxides of lithiated compounds of manganese, cobalt, vanadium, or nickel. This can be described in the simplest case stoichiometrically as LiMn202, LiCo02, LiV202 or LiNi02.

These oxides of compounds react reversibly with substances, such as graphite, which is capable of incorporating lithium ions into their lattice, the lithium ions are removed from the crystalline lattice and the metal ions within it, such as the ions of manganese, cobalt, or nickel, which are oxidized. In an electrochemical cell this reaction can be used to store electrical energy by separating the compound that accepts the lithium ions, ie the anode material, from the oxide of the lithium-containing compound, ie the cathode material, by means of a electrolyte through which the lithium ions that form the oxide of the compound can migrate to the anode material (charge). Suitable compounds for the reversible storage of lithium ions are usually secured to the collecting electrodes by means of a binder substance. During cell loading, the electrons flow through an external voltage source and the lithium cations through the electrolyte into the anode material. When the cell is used, the lithium cations flow through the electrolyte, while the electrons flow from the anode material to the cathode material through a charge.

In order to avoid a short circuit inside the electrochemical cell, a layer that is electrically isolated but that is permeable to lithium cations is located between the two electrodes. This can be called as a solid electrolyte or a conventional separator. As is well known solid electrolytes and separators are composed of a carrier material, incorporated in what is a dissociable compound containing lithium cations and serve to increase the conductivity of the lithium ion and also usually other additives, such as solvents . The icoporous films have for some time been proposed as separators. For example, GB 2 027 637 describes a microporous film comprising a matrix with 40 to 90% by volume of a polyolefin and from 10 to 60% by volume of an inorganic filler and other constituents as defined therein respectively. . The matrix described there has 30 to 95% by volume of cavities, based on the volume of the film, and is a separator for lead accumulators. EP-B 0 715 364 discloses a two-layer battery separator with current interruption characteristics. The described battery separator has a first microporous membrane having an interrupting function and which has been produced from a material selected from the class consisting of polyethylene, a mixture comprising essentially polyethylene and a polyethylene copolymer. The separator also has a second microporous membrane which has a reinforcing function and which has been produced from a material selected from the class consisting of polypropylene, of a mixture essentially comprising polypropylene and a polypropylene copolymer. In accordance with the description, this separator has a better mechanical strength and transit energy than that of the prior art. EP-A 0 718 901 describes a three-layer battery separator with current interruption characteristics. This separator comprises a first and third microporous polypropylene membrane which in turn includes a microporous polyethylene membrane, wherein the first and third membranes have a greater resistance to perforation and a higher melting point than the second membrane. EP-A-0 708 791 discloses a polymeric electrolyte of composite material in the form of the membrane, which has an ionic conductive polymer gel applied to a matrix material made of a porous polytetrafluoroethylene membrane.

DE-A 198 59 826.3 discloses a suitable composite material as a separator in electrochemical cells and comprising a conventional layered separator and at least one other layer, wherein these comprise a solid and a polymeric binder substance, a polymer or a copolymer which has, along the chain, reactive groups, terminally and / or laterally which are capable of having degradation or cross-linking reactions when exposed to heat radiation and / or UV. It is an object of the present invention, taking into account this prior art, to provide a separator which also has an interrupting mechanism and, in addition, has a dimensional stability at high temperatures (> 150 ° C) and also provides a improved mechanical strength, and in addition, has excellent ion conduction properties or is an alternate system to the compound of DE-A 19850826.3. It has been found that this objective is achieved by means of a compound comprising at least one first layer comprising a composition comprising: (a) from 1 to 99% by weight of a solid (I) with a particle size primary from 5 nm to 100 μm or a mixture produced from at least two solids, (b) from 99 to 1% by weight of a binder substance (II) polymer obtained by means of polymerization: bl) from 5 to 100% by weight, based on the binder substance (II), of a condensation product III manufactured from a) at least one compound IV which is capable of reacting with a carboxylic acid or with a sulphonic acid or with a derivative or with a mixture of two or more of these, and ß) at least one mole per mole of the compound IV of a carboxylic acid or a sulfonic acid V which has at least one functional group capable of carrying out the polymerization of the free radical, or of a derivative thereof or of a mixture of two or more of those Y b2) from 0 to 95% by weight, based on the binder substance (II), of another compound VII with an average molecular weight (average number) of at least 5000 having polyether segments in a main or side chain, wherein at least one first layer has been applied to at least one second layer comprising at least one conventional separator. The present invention further discloses a compound of the aforementioned type, wherein the binder substance (IIA) polymer is obtained by polymerizing b) from 5 to 75% by weight, based on the binder substance (IIA), of a compound VI which differs from the carboxylic acid or sulfonic acid V and any derivative thereof and is capable of polymerizing free radicals, or a mixture of two or more of these Y b2) from 25 to 95% by weight, based on the binder substance (IIA), of another compound VII with average molecular weight (average number) of at least 5000 having polyether segments in the main or side chain. The composition present in at least one first layer, and the preparation thereof, is now described in more detail below. The solid I is preferably selected from the class consisting of an inorganic solid, preferably a basic inorganic solid, selected from the class consisting of oxides, mixed oxides, carbonates, silicates, sulfates, phosphates, amides, imides, nitrides and carbides of elements of the 1st, 2nd, 3rd or 4th main group, of the 4th transition group, or the periodic table; a polymer selected from the class consisting of polyethylene, polypropylene, polystyrene, polytetrafluoroethylene and polyvinylidene fluoride, polyamides, polyimides; a solid dispersion comprising such a polymer; glass powder, nano-glass particles, for example Monosper® (Merck), microglass particles, for example Spheriglas® (Potters-Ballotini), nanofibers and a mixture of two or more of these, where the composition obtained can be used as a solid electrolyte and / or separator. The term "solid III" comprises any compound which is solid under standard conditions of temperature and pressure and which does not accept or release electrons during battery operation under the conditions prevailing during the charging of the batteries, in particular lithium-ion batteries. The compounds mainly used as a solid III in this layer are the inorganic solids, preferably a basic inorganic solid selected from the class consisting of oxides, mixed oxides, carbonates, silicates, sulfates, phosphates, amides, imides, nitrides and carbides of elements. of the 1st, 2nd, 3rd or 4th main group, of the 4th transition group, or the periodic table; a polymer selected from the class consisting of polyethylene, polypropylene, polystyrene, polytetrafluoroethylene and polyvinylidene fluoride, polyamides and polyimides; a solid dispersion comprising such a polymer; and a mixture of two or more of these.

A particular mention may be made, by way of example, of: the oxides, for example, silicon dioxide, aluminum oxide, magnesium oxide and titanium dioxide, oxides of compounds, for example elements silicon, calcium, aluminum, magnesium, titanium; silicates, for example step-type or cellular silicates, ino-, phyllo- and tectosilicates, for example talc, pyrophyllite, muskovite, phlogophyte, anphyllobes, nesosilicates, pyroxenes, sorosilicates, zeolites, feldspar , olastonite, in particular hydrophobic wolastonite, mica, phyllosilicates; sulphates, for example alkali metal sulfates and alkaline earth metal sulfates; carbonates, such as alkali metal carbonates and alkaline earth metal carbonates, for example calcium, magnesium or barium carbonate or lithium, potassium or sodium carbonate, phosphates, such as apatites; the amides; the imides; the nitrides, the carbides; polymers for example, polyethylene, polypropylene, polystyrene, polytetra-fluoroethylene, polyvinylidene fluoride, polyamides, polyimides, or other thermoplastics, thermosets or microgels, cross-linked polymer particles, for example Agfaperl®, solid dispersions, in particular those comprising the aforementioned polymers, also mixtures of two or more of the solids mentioned above. The solid I used according to the invention also comprises inorganic lithium ion conductive solids, preferably a basic inorganic lithium ion conducting solid. Those that can be mentioned are: lithium borates, for example Li4B60u * xH20, Li3 (B02) 3, Li2B07, * xH20, LiB02, where the number x can be from 0 to 20; lithium aluminates, for example Li20 * A1203 * H20, Li2Al20, LiA102; lithium aluminosilicates, for example lithium-containing zeolites, feldspars, feldspar substitutes, phylo- and inosilicates, and in particular LiAlSi206 (spodumene), LiAlSi4O? 0 (petulite), LiAlSi0 (eucliptite), micas, for example K [Li, Al] 3 [AlSi] 4O? o (F-OH) 2, K [Li, Al, Fe] 3 [AISi] 4O10 (F-OH) 2; lithium zeolites, in particular those in the form of fiber, sheet or cube, and in particular those with the general formula Li2 / zO * A1203 * xSi02 * and H20 where z is the valence, x is from 1.8 to about 12 ey is from 0 to about 8; lithium carbides, for example Li2C2, Li4C; the Li3N; lithium oxides and compound lithium oxides, for example LiAl02, Li2Mn03, Li20, Li202, Li2Mn04, Li2Ti03; Li2NH; LiNH2; lithium phosphates, for example LY3PO4, LiP03, LIAIFPO4, LiAl (OH) P? 4, LiFeP04, LiMnP04; the Li2C03; lithium silicates in the form of silicates of the stepped or cellular type, ino-, phyllo- and tectasilicates, for example Li2Si03, Li2Si0 and Li6Si2; lithium sulfates, for example Li2S0, LiHS0, LiKS0; and also the lithium compounds mentioned as compound Ib, where the presence of conductivity black is excluded when these are used as solid I; and they are also mixtures of two or more of the lithium ion conductive solids mentioned above. Preferred solids I are hydrophobic solids I, more preferably hydrophobized compounds of the aforementioned type. The basic solids are particularly suitable here. For the purposes of the invention, basic solids are those whose mixture with a liquid, a diluent containing water having a pH of no more than 7 as a pH higher than this diluent. The solids may advantageously be very substantially insoluble in the liquid used as the electrolyte, and they are also electrochemically inert in the middle of the battery. Suitable solids I are those which have a particle size of 5 nm to 20 μm, preferably from 0.01 to 10 μm and in particular from 0.1 to 5 μm, the particle sizes provided are determined by means of electron microscopy. The melting point of the pigments is preferably above the usual operating temperature of the electrochemical cell, and the melting points above 120 ° C, in particular above 150 ° C, have proven to be particularly advantageous. The pigments can be symmetrical in their external form, that is to say they have a dimensional proportion of height with width with length (dimensional proportion) of about 1 and are sized as spheres or pellets, to be approximately round in shape, or to be in the form of any desired polyhedron, such as cuboids, tetrahedrons, hexahedra, octahedra or dipyramids, or they can be deformed or asymmetric, that is they have a dimensional ratio of height to width to length (dimensional proportion) that is not equal to 1 and be, for example, example, in the form of needles, asymmetric tetrahedron, asymmetric bipyramids, asymmetric hexa- or octahedron, lamellae or plates, or in the form of fibers. If the solids are asymmetric particles, the upper limit given above for the primary particle size refers to the smallest axis in each case. The composition used according to the invention comprises from 1 to 99% by weight, preferably from 15 to 90% by weight, more preferably from 25 to 85% by weight, in particular from 50 to 80% by weight, of a solid. , and from 1 to 99% by weight, preferably from 10 to 85% by weight, more preferably from 15 to 75% by weight, in particular from 20 to 50% by weight, of the polymeric binder substance II or IIA. The compounds that can be used as the compound IV, which is capable of reacting with a carboxylic or sulphonic acid V or with a derivative or with a mixture of two or more of these compounds, are in principle any of the compounds that meet this criterion . Compound IV is preferably selected from the class consisting of mono- and polyhydric alcohols whose main chain has only carbon atoms; mono- and polyhydric alcohols whose main chain also has at least two carbon atoms, at least one atom selected from the class consisting of oxygen, phosphorus and nitrogen; silicon-containing compounds; amines having at least one primary amino group; amines having at least one secondary amino group; amino alcohols; monohydric thiols; compounds having at least one lime group and at least one hydroxyl group; and mixtures of two or more of these. Among these, compounds IV are preferred which have two or more functional groups capable of reacting with the carboxylic or sulphonic acid.

When use is made of the IV compounds having amino functional groups, it is preferred to use those having secondary amino groups, so that after condensation / degradation there are no non-free NH groups present in the binder substance II in whole or in single small amounts of these groups. The details of the preferred compounds that can be mentioned are: Mono- or polyhydric alcohols whose main chain has only carbon atoms and having from 1 to 20 alcoholic OH groups, preferably from 2 to 20 and in particular from 2 to 10 groups , in particular di-, tri- and tetrahydric alcohols, preferably having from 2 to 20 carbon atoms, for example ethylene glycol, 1,2- and 1,3-propanediol, 1,2- and 1, 3-butanediol, 1,4-butenediol, 1,4-butynediol, 1,6-hexanediol, neopentyl glycol, 1,2-dodecanediol, glycerol, trimethylpropane, pentaerythritol and sugar alcohols, hydroquinone , novolak and bisphenol A, but, as apparent from the above definition, it is also possible to use monohydric alcohols, for example methanol, ethanol, propanol, n-butanol, sec-butanol or t-butanol; it is also possible to use polyhydroxyolefins, preferably one having two terminal hydroxyl groups, for example, a, w-dihydroxybutadiene; Polyester polyols as is known, for example, from the Encyclopaedia der Technischen Chemie, 4th ed., Vol.19 pp. 62-65 and obtained, for example, by reacting the dihydric alcohols with polybasic, preferably dibasic, polycarboxylic acids; The mono- or polyhydric alcohols whose main chain contains, in addition at least two carbon atoms, at least one oxygen atom, preferably polyether alcohols, for example, polymerization products of alkylene epoxides, such as isobutylene oxide, propylene oxide, ethylene oxide, 1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyhexane, tetrahydrofuran and styrene oxide; it is possible to make use of the modified polyether alcohols of the terminal group, for example the polyether alcohols modified with the NH2 end groups; these alcohols preferably have a molecular weight (average number) of from 100 to 5000, more preferably from 200 to 1000, in particular from 300 to 800; compounds of this type are known per se and commercially available, for example, under the trade names of Pluriol® or Pluronic® (BASF Aktiengesellschaft); the alcohols as defined above wherein some or all of the carbon atoms have been replaced by the silicon; their use can be made here in particular of polysiloxanes or alkylene oxides-siloxane copolymers or mixtures of polyether alcohols and polysiloxanes, as described, for example, in EP-B 581 296 and EP-A 525 728; which is mentioned above also applies to the molecular weight of these alcohols; alcohols as defined above, in particular polyether alcohols, wherein some or all of the oxygen atoms have been replaced by sulfur atoms; which has been mentioned above applies to the molecular weight of these alcohols; mono- or polyhydric alcohols whose main chain comprises, in addition at least two carbon atoms, at least one phosphorous atom or at least one nitrogen atom, for example diethanolamine and triethylamine; the lactones which are derived from the compounds of the formula HO- (CH 2) z -COOH, where z is a number from 1 to 20, for example e-caprolactone, β-propiolactone, β-butyrolactone or methyl-e -caprolactone; compounds containing silicon, for example di- or trichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane or dimethylvinylchlorosilane; silanols, for example trimethylsilanol; amines having at least one primary and / or secondary amino group, for example butylamine, 2-ethylhexylamine, ethylenediamine, hexamethylenediamine, diethylenetriamine, tetraethylenepentamine, pentaethylenehexamine, aniline or phenylenediamine.; polyetherdiamines, for example 4,7-dioxadecane-1, 10-diamine or 4,11-dioxatetradecane-1, 14-diamine; mono- or polyhydric thiols, for example aliphatic thiols, for example methanethiol, ethanethiol, cyclohexanothiol or dodecanethiol; aromatic thiols, for example, thiophenol, 4-chlorothiophenol or 2-mercaptoaniline; the compounds having at least one thiol group and at least one hydroxyl group, for example 4-hydroxythiophenol, or other monothio derivatives of the polyhydric alcohols defined above; amino alcohols, for example ethanolamine, n-methylethanolamine, N-ethylethanolamine, N-butylethanolamine, 2-amino-1-propanol, 2-amino-1-phenoletanol, mono- or polyaminopolyols having more of two aliphatically bound hydroxyl groups, for example tris (hydroxymethyl) methylamine, glucamine or N, N'-bis (2-hydroxyethyl) ethylene diamine. It is also possible to use mixtures of two or more of the IV compounds defined above. According to the invention, the aforementioned IV compounds are condensed with a carboxylic or sulfonic acid V, which has at least one functional group capable of carrying out the polymerization of the free radical, or with a derivative thereof or with a mixture of two or more of these. At least one, preferably all, free groups which are capable of condensation with the compounds IV are condensed with the compound V. For purposes of the present invention, the carboxylic or sulphonic acid V can in principle be any carboxylic or sulphonic acid which it has at least one functional group capable of carrying out the polymerization of the free radical, or other derivatives thereof. The term "derivatives" used herein includes both compounds derived from a carboxylic or sulfonic acid modified in the acid function, for example esters, acid halides or anhydrides, and compounds derived from the modified carboxylic or sulfonic acids in their backbone. carbon, for example, halocarboxylic or halosulfonic acids.

The particular compounds V that can be mentioned are: α, β-unsaturated carboxylic acids and unsaturated ß, Y ~ carboxylic acids. Particularly suitable unsaturated α, β-carboxylic acids are those of the formula: where R1, R2 and R3 are hydrogen or C? ~ C alkyl radicals, among which preference is given to acrylic and methacrylic acids; it can be successfully used cinnamic acid, maleic acid, fumaric acid, itaconic acid or vinylbenzoic acid, or other derivatives thereof, for example anhydrides, such as maleic or itaconic anhydride; the halides, in particular the chlorides, for example an acryloyl chloride or a methacryloyl chloride; esters, for example (cyclo) alkyl (meth) acrylates having up to 20 carbon atoms in the alkyl radical, for example methyl, ethyl, propyl, butyl, hexyl, 2-ethylhexyl, stearyl, lauryl, cyclohexyl, benzyl, trifluoromethyl, hexafluoropropyl or tetrafluoropropyl (meth) acrylate, propylene glycol mono (meth) acrylates, polyethylene glycol mono (meth) acrylates, poly (meth) polyhydric alcohol acrylates, for example di (meth) acrylate glycerol, di (meth) acrylate trimethylolpropane, di- or tri (meth) acrylate pentaerythritol, bis (mono (2-acryloxy) ethyl) carbonate diethylene glycol, or poly (meth) acrylates of alcohols which in turn have a group capable of polymerizing the free radical, for example the esters of (meth) acrylic acid and the vinyl alcohol and / or allyl alcohol; vinyl esters of other aliphatic or aromatic carboxylic acids, for example. vinyl acetate, vinyl propionate, vinyl butyrate, vinyl hexanoate, vinyl octanoate, vinyl decanoate, is vinyl stearate, vinyl palmitate, vinyl crotonoate, vinyl adipate, the divinyl sebacate, the vinyl 2-ethylhexanoate or the vinyl trifluoroacetate. the allyl esters of other aliphatic or aromatic carboxylic acids, for example allyl acetate, allyl propionate, allyl butyrate, allyl hexanoate, allyl octanoate, allyl decanoate, is allyl stearate, allyl palmitate, allyl crotonoate, allyl salicylate, allyl lactate, diallyl oxalate, diallyl malonate, diallyl succinate, diallyl glutarate, diallyl adipate, diallyl pimelate, diallyl cinnamate, diallyl maleate, diallyl phthalate, diallyl isophthalate, triallyl 1, 3, 5-benzenetricarboxylate, allyl trifluoroacetate, allyl perfluorobutyrate or allyl perfluorooctanate; ß, ω-unsaturated carboxylic acids or derivatives thereof, for example vinylacetic acid, 2-methylvinylacetic acid, isobutyl 3-butenoate, allyl 3-butenoate, 2-hydroxy-3-butenoate allyl or the diketone; sulfonic acids, for example vinylsulfonic acid, allyl- or methallylsulfonic acid, or other halides or esters thereof, vinyl benzenesulfonate or 4-vinylbenzenesulfonamide. it is also possible to use the mixtures of two or more of the carboxylic and / or sulphonic acids described above, the individual examples which can be mentioned for compound VI capable of polymerization of the free radical which can be used to prepare the binder substance (HA ) are: olefinic hydrocarbons, for example ethylene, propylene, butylene, isobutene, hexane and higher homologs and vinylcyclohexane; the (meth) acrylonitrile; halogenated olefinic compounds, for example vinylidene fluoride, vinylidene chloride, vinyl fluoride, vinyl chloride, hexafluoropropene, trifluoropropene, 1,2-dichloroethylene, 1,2-difluoroethylene and tetrafluoroethylene; vinyl alcohol, vinyl acetate, N-vinylpyrrolidone, N-vinylimidazole and vinylformamide; phosphorous nitride chlorides, for example phosphorus dichloride nitride, hexachloro (triphosphazene), and also derivatives thereof partially or completely substituted by alkoxy, phenoxy, amino or fluoroalkoxy groups, ie compounds that can be polymerized to provide polyphosphazenes; aromatic olefinic compounds, for example styrene or a-methylstyrene; vinyl ethers, for example methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, decyl, dodecyl, 2-ethylhexyl, cyclohexyl, benzyl, trifluoromethyl , the vinyl ether hexafluoropropyl or tetrafluoropropyl. Of course it is also possible to use mixtures of the above compounds VI, in which case the copolymers are produced. Depending on the nature of the preparation, these contain randomly distributed monomers or representative block copolymers. These VI compounds, like the condensation products III, are polymerized in known manners customary to those skilled in the art, preferably by means of free radical polymerization, and that which is mentioned below in relation to compound VII applies here to the molecular weights obtained. The possible compounds VII are composed primarily of an average molecular weight (average number) of at least 5000, preferably from 5000 to 20,000,000, in particular from 100,000 to 6,000,000, and capable of solvating the lithium cations and functioning as binder substances. Examples of suitable compounds VII are polyethers and copolymers having at least 30% by weight of the following structural unit, based on the total weight of compound VII: where R1, R2, R3 and R4 are aryl or alkyl groups, preferably methyl groups, or hydrogen and are identical or different and may contain heteroatoms, such as oxygen, nitrogen, sulfur or silicon. Compounds of this type are described, for example, in M.B Armand et al., Fast Ion Transport in Solids, Elsevier, New York, 1979, p. 131-136 or in FR-A 7832976. Compound VII can be composed of mixtures of two or more compounds of this type. The polymeric binders II and HA defined above can also be in the form of a foam, in which case the solid I is dispersed as such there.

Compound VII advantageously has an average molecular weight (average number) of from 5,000 to 100,000,000, preferably from 50,000 to 8,000,000. The binder substance II can be obtained by reacting from 5 to 100% by weight, preferably from 30 to 70% by weight, based on the binder substance II, of at least one condensation product III and from 0 to 95% by weight, in particular from 30 to 70% by weight, based on the binder substance II, of a compound VII. The compound VII of the binder substance HA advantageously has an average molecular weight (average number) of from 5,000 to 100,000,000, preferably from 50,000 to 8,000,000. The binder substance HA can be obtained by reacting from 5 to 75% by weight, preferably from 30 to 70% by weight, based on the binder substance HA, of a compound VI and from 25 to 95% by weight, in from 30 to 70% by weight, based on the binder substance HA, of a compound VII. To produce a layer used according to the invention, a mixture can be prepared from a solid I, a condensation product III and, if desired, a compound VII, or a mixture can be prepared from a solid III , a compound VI and a compound VII and customary additives, for example plasticizers, preferably plasticizers containing polyethylene oxide or plasticizers containing polypropylene oxide. Other HIV polymers that can be used can comprise thermoplastic polymers and ion conductors. Those to be mentioned in particular are: 1) Polycarbonates, for example polyethylene carbonate, polypropylene carbonate, polybutadiene carbonate and polyvinylidene carbonate. 2) Homopolymers, block polymers and copolymers are prepared from a) olefinic hydrocarbons, for example ethylene, propylene, butylene, isobutene, propene, hexane, or higher homologs, butadiene, cyclopentane, cyclohexane, nobornene, vinylcyclohexane, 1,3-pentadiene, 1,3-, 1,4- and 1,5-hexadiene, isoprene and vinylbornene; b) aromatic hydrocarbons, such as styrene and methylstyrene; c) acrylates or methacrylates, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, decyl, dodecyl, 2-ethylhexyl, cyclohexyl, benzyl , trifluoromethyl, hexafluoropropyl acrylate and tetrafluoropropyl and, respectively, methacrylate; d) acrylonitrile, methacrylonitrile, N-methylpyrrolidone, N-vinylimidazole and vinyl acetate; e) vinyl ethers, for example vinyl ethers of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, decyl, dodecyl, 2-ethylhexyl, cyclohexyl, benzyl, trifluoromethyl, hexafluoropropyl and tetrafluoropropyl; f) polymers and copolymers of halogen-containing olefinic compounds, for example vinylidene fluoride, vinylidene chloride, vinyl fluoride, vinyl chloride, hexafluoropropene, trifluoropropene, 1,2-dichloroethylene, , 2-difluoroethylene and tetrafluoroethylene; preferably the polymers or copolymers of vinyl chloride, of acrylonitrile, or of vinylidene fluoride; copolymers made from vinyl chloride and vinylidene chloride, vinyl chloride and acrylonitrile, vinylidene fluoride and hexafluoropropylene fluoride and vinylidene fluoride with hexafluoropropylene; terpolymers manufactured from vinylidene fluoride and hexafluoropropylene, and also from a member of the class consisting of vinyl fluoride, tetrafluoroethylene, and trifluoroethylene; in particular a copolymer manufactured from vinylidene fluoride and hexafluoropropylene; and with an additional preference of a copolymer comprising from 75 to 92% by weight of vinylidene fluoride and from 8 to 25% by weight of hexafluoropropylene. g) 2-vinylpyridine, 4-vinylpyridine and vinylene carbonate.

Regulators, for example mercaptans, can be used during the preparation of the aforementioned polymers if this is necessary and / or desirable. 3) The polyurethanes obtainable, for example, by reacting a) organic diisocyanates having from 6 to 30 carbon atoms, for example the non-cyclic aliphatic diisocyanates, for example the 1,5-hexamethylene diisocyanate and the 1-6 hexamethylene diisocyanate, the cyclic aliphatic diisocyanates, for example 1,4-cyclohexylene diisocyanate, dicyclohexylmethane diisocyanate and isophorone diisocyanate, or aromatic diisocyanates, for example 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, tetramethylxylene m-diisocyanate, tetra-methylxylene p-diisocyanate, 1,5-tetrahydro-naphthalene diisocyanate and 4,4 '-diphenyl methane diisocyanate, or mixtures of such compounds, with b) polyhydric alcohols, example polyesterols, polyetherols and diols. The polyesterols are advantageously linear polymers predominantly having terminal OH groups, preferably those having two or three, in particular two, terminal OH groups. The acid number of the polyesterols is less than 10 and preferably less than 3.

The polyesterols can be prepared in a simple manner by the esterification of aliphatic or aromatic dicarboxylic acids having from 4 to 15 carbon atoms, preferably from 4 to 6 carbon atoms, with glycols, preferably glycols having from 2 to 25 carbon atoms. carbon, or polymerizable lactones having from 3 to 20 carbon atoms. Examples of dicarboxylic acids which may be used are glutaric acid, pimelic acid, suberic acid, sebacic acid, dodecanoic acid, and preferably adipic acid and succinic acid. Suitable dicarboxylic acids are the acid terephthalic acid, isophthalic acid, phthalic acid, or mixtures of these dicarboxylic acids with other dicarboxylic acids, for example, diphenic acid, sebacic acid, succinic acid, and adipic acid. The dicarboxylic acids can be used individually or as mixtures. To prepare the polyesterols it can sometimes be advantageous to use, instead of the dicarboxylic acids, the corresponding acid derivatives, such as carboxylic anhydrides or carboxylic chlorides. Examples of suitable glycols are diethylene glycol, 1,5-pentanediol, 1,1-decanediol and 2,2,4-trimethyl-1,5-pentanediol. Preference is given for the use of 1,2-ethanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 2,2-dimethyl-1, 3-propanediol, 1,4-dimethylolcyclohexane, 1,4-diethanolcyclohexane and ethoxylated or propoxylated products of 2,2-bis (4-hydroxyphenylene) propane (bisphenol A). Depending on the properties desired in the polyurethanes, the polyols can be used alone or as a mixture in various quantity proportions. Examples of the lactones suitable for preparing the polyesterols are a, a-dimethyl-β-propiolactone, β-butyrolactone and preferably e-caprolactone. The polyetherols are essentially linear substances having terminal hydroxyl groups and each containing bonds. Suitable polyetherols can be easily prepared by a polymerizable cyclic ether, such as a tetrahydrofuran, or by reacting one or more alkylene oxides having from 2 to 4 carbon atoms in the alkylene radical with a starting molecule which contains, linked to the alkylene radical, two active hydrogen atoms. Examples of the alkylene oxides are ethylene oxide, 1,2-propylene oxide, epichlorohydrin, 1,2-butylene oxide and 2,3-butylene oxide. The alkylene oxides can be used individually, alternating in succession or as a mixture. Examples of the starting molecules used are water, glycols, such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol, amine, such as ethylenediamine, hexamentylenediamine and 4,4'-diaminodiphenylmethane, and amino alcohols, such as ethanolamine. Suitable polyesterols and polyetherols, and also the preparation thereof, are described, for example, in EP-B 416 386, and suitable polycarbonatediols, preferably those based on 1,6-hexanediol, and also the preparation thereof, are described , for example, in US-A 4 131 731. Amounts of up to 30% by weight, based on the total weight of the alcohols, of the aliphatic diols having from 2 to 20 carbon atoms, preferably from 2 to 10. carbon atoms can be advantageously used, for example, 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,5-pentanediol, 1,1-decanediol, 2-methyl. -l, 3-propanediol, 2,2-dimethyl-l, 3-propanediol, 2-methyl-2-butyl-1,3-propanediol, 2,2-dimethyl-1,4-butanediol, 1,4 -dimethylolcyclohexane, neopentyl glycol hydroxypivalate, diethylene glycol, triethylene glycol, or methyldiethanolamine, or aromatic-aliphatic or aromatic-cycloaliphatic diols having from 8 to 30 carbon atoms, wherein possible aromatic structures are heterocyclic ring systems or isocitic ring systems, such as naphthalene derivatives in particular benzene derivatives, such as bisphenol A, symmetrically double ethoxylated bisphenol A, symmetrically double propoxylated bisphenol A, bisphenol A derivatives more highly propoxylated or ethoxylated or the bisphenol F derivatives, or else mixtures of the compounds of this type. Amounts of up to 5% by weight, based on the total weight of the alcohols, of the aliphatic triols having from 3 to 15 carbon atoms, preferably from 3 to 10 carbon atoms, can advantageously be used, for example trimethylpropane or glycerol, the reaction product of compounds of this type with ethylene oxide and / or propylene oxide, or else mixtures of such compounds. Polyhydric alcohols can have functional groups, for example neutral groups, such as siloxane groups, basic groups, such as in particular tertiary amino groups, or acid groups, or salts thereof, or groups which are easily converted to acid groups, which are introduced via a polyhydric alcohol. The use can advantageously be made of diol components which have groups of this type, for example N-methyldiethanolamine, diethyl N, N-bis (hydroxyethyl) aminomethylphosphonate or N, N-bis (hydroxyethyl) -2-aminoacetate of 3-sulfonyl, or dicarboxylic acids which have groups of this type and can be used to prepare polyesterols, for example 5-sulfoisophthalic acid. The acid groups are in particular the carboxyl or ammonium group of phosphoric acid, phosphonic acid, sulfuric acid, sulfonic acid. Examples of the groups which easily develop into the acid groups are the ester groups or salts, preferably the alkali metals, such as lithium, sodium or potassium. 4) The polyesterols described above per se, where they matter, should be provided to obtain molecular weights of 10,000 to 2,000,000, preferably 50,000 to 1,000,000. 5) Polyamines, polysiloxanes and polyphosphazenes, particularly those discussed in the polymer description Hb2 above. 6) The polyetherols, as described, for example in the previous discussion of the Hbl polymer, as a compound (c), or in the discussion of the polyurethanes. It is, of course, also possible to use mixtures of the above HIV polymers. The HIV copolymers used according to the invention may, depending on the manner of preparation, contain a random distribution of the monomers, or they may be block copolymers.

The HIV polymer is polymerized in a conventional manner known to the skilled worker, preferably free radical polymerization. The HIV polymer can be used in high molecular weight form or oligomerically or as mixtures thereof. The ratio of the HIV polymer in the polymeric binder substance II to HA is generally from 0 to 99% by weight, preferably from 20 to 80% by weight and more preferably from 40 to 70% by weight. The present invention preferably provides compounds with a first layer which comprises the following composition: The first layer as defined above, wherein the HIV polymer is selected from the class consisting of polymers or copolymers of vinyl chloride, acrylonitrile, fluoride of vinylidene; copolymers of vinyl chloride and vinylidene chloride, vinyl chloride and acrylonitrile, vinylidene fluoride and hexafluoropropylene, or vinylidene fluoride with hexafluoropropylene; thermopolymers of vinylidene fluoride and hexafluoruropropylene and also a member of the group consisting of vinyl fluoride, tetrafluoroethylene and trifluoroethylene, is preferably a copolymer of vinylidene fluoride and hexafluoropropropylene.

The compositions used according to the invention can further comprise a plasticizer IX. However, you do not need to use a plasticizer. The proportion of the plasticizer IX, if used, based on the composition, is from 0.1 to 100% by weight, preferably from 0.5 to 50% by weight and in particular from 1 to 20% by weight. Examples of plasticizers IX are those described in DE-A 198 19 752, preferably dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethylene carbonate, 1, 2-propylene carbonate, 1, 3 -propylene carbonate, organic phosphorus compounds, in particular phosphates and phosphonates, for example trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tris (2-ethylhexyl) phosphate, ethers of oxides of polyalkylene and polyalkylene oxide esters, for example, diglyme compounds, triglyme compounds and tetraglime compounds, polymeric plasticizers, for example, thermoplastic polyurethanes or polyamides, and also mixtures thereof. The compositions used according to the invention can be dispersed or dissolved in an organic or inorganic diluent, preferably an organic liquid diluent, in which the mixture according to the invention could have a viscosity of preferably 100 to 50,000 mPas, and then be applied to a substrate in a manner known per se, for example spray coating, pouring, dip treatment, spin coating, roll coating, relief surface printing, gravure or planography or stencil printing. The additional process can continue as usual, for example when removing the diluent and curing the mixture. Suitable organic diluents are aliphatic ethers, in particular tetrahydrofuran and dioxane, hydrocarbons, in particular mixtures of hydrocarbons, such as petroleum spirit, toluene or xylene, aliphatic esters, in particular ethyl acetate and butyl acetate, and ketones, in particular acetone, ethyl methyl ketone and cyclohexane, and also DMF and NMP. It is also possible to use combinations of diluents of these types. Possible substrates are the materials usually used by electrodes, preferably metals, such as aluminum or copper. It is also possible to use temporary substrates, such as films, in particular polyester films, such as polyethylene terephthalate films. Films of this type can advantageously have a release layer, preferably made from polysiloxanes.

The separators can also be produced thermoplastically, for example by injection molding, melt casting, compression, kneading or injection molding, and if desired the composition used according to the invention can be laminated in a subsequent step. After the film has been formed of the composition used according to the invention, the volatile components, such as solvents and plasticizers, can be removed. The composition used according to the invention can be degraded in a manner known per se, for example by irradiation with ionic or ionizing radiation, or an electron beam, preferably with an acceleration voltage of 20 to 2000 kV and a dose of radiation from 5 to 50 Mrad, or with UV or visible light, advantageously added, in the usual manner, an initiator such as a benzyl dimethyl ketal or 1,3,5-trimethylbenzoyltriphenylphosphine oxide in amounts of in particular not more than 1% by weight, based on the polymeric binder substance II / HA, and a degradation generally within a period of 0.5 to 15 minutes, by polymerization of free radical via thermal degradation, preferably above 60 ° C, where a initiator advantageously, for example azobisisobutyronitrile in amounts of generally not more than 5% by weight, preferably from 0.05 to 1% by weight, based on the polymeric binder substance II / HA; by electrochemically induced polymerization, or by ionic polymerization, for example by acid catalyzed cationic polymerization, where the possible catalyst is primarily acids, preferably Lewis acids, such as BF3, or in particular LiBF4 or LiPF6. Catalysts containing lithium ions, such as LiBF4 or LiPF6 can advantageously remain here in the solid electrolyte or the separator as the salt that increases the conductivity. The degradation described above preferably takes place under an inert gas. The irradiation time here can according to the invention be controlled so that each complete degradation takes place or exists merely in a short period of pre irradiation of UV light to provide only partial degradation or cross-linking. As mentioned above, at least a second layer of the molding according to the invention comprises a conventional separator. According to the invention, any conventional separator can be used here. The following should be mentioned in particular in this connection: - separators based on microporous polyolefin films, as are commercially available, for example, under the tradenames Celgard® and Hipore® and described, inter alia, in EP-A 0 718 901 and EP-B 0 715 364, the entire field of both of which are incorporated within the present application by way of reference; polyethylene films and polypropylene films, and also films which comprise polyethylene binders and, respectively, polypropylene with other polymers, are similarly useful here; - the microporous polytetrafluoroethylene (PTFE) films of Goretex, as described, for example, in EP-A 0 798 791, which are also incorporated within the present application by way of reference; fabrics, fibers, and also nonwovens, all of which can be produced by using fibrous polymer materials, for example polyolefin, polyamide and polyester fibers; films available under the trade name Nafion®; films based on a copolymer of vinylidene difluoride and hexafluoropropene, as described, for example, in US 5 540 741 and US 5 478 668; - homopolymers, block polymers and copolymers which in each case contain a filler and can be obtained by extrusion, prepared from (a) olefinic hydrocarbons, for example ethylene, propylene, butylene, isobutane, propene, hexene or lighter counterparts , butadiene, cyclopentene, cyclohexene, norbornene or vinylcyclohexane; (b) aromatic hydrocarbons, for example styrene or methylstyrene; (c) acrylates or methacrylates, such as acrylates and methacrylates of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, decyl, dodecyl, 2-ethylhexyl, cyclohexyl, benzyl, trifluoromethyl, hexafluoropropyl or tetrafluoropropyl; (d) acrylonitrile, methacrylonitrile, N-methylpyrrolidine, N-vinylimidazole or vinyl acetate; (e) vinyl ethers, for example, methyl vinyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, decyl, dodecyl, 2-ethylhexyl, cyclohexyl, benzyl, trifluoromethyl, hexafluoropropyl or tetrafluoropropyl; (f) halogen-containing olefinic compounds, such as vinyl chloride, vinyl fluoride, vinylidene fluoride, vinylidene chloride, hexafluoropropene, trifluoropropene, 1,2-dichloroethene, 1,2-difluoroethene, or tetrafluoroethene, where the solids ( I) according to the invention are used as fillers in these polymers; the composition and production of extruder films of this type are described in detail in DE-A 197 13 072.0. To produce the novel composite material, at least one first layer is contacted with at least one second layer, and according to the invention any known process for conducting layers of this type together can be used. For example, the first layer can be applied to the second layer by processes at atmospheric pressure, for example, by melting or treating the starting material of the first layer, or also by processes at sub-atmospheric pressure, for example, extrusion, lamination, in particular hot rolling, calendering or compression. The resulting compound here can be cured or degraded by radiation, or electrochemically or thermally. In addition, the starting material for at least one first layer can first be cured or thermally degraded, each partially or completely, and then, as described above, by contacting atmospheric pressure or sub-atmospheric pressure with the second layer. used according to the invention. If the pre-fabricated films, that is to say, at least one first layer in the form of a film and also the conventional separator in the form of a film, are also contacted, these preferably take place by rolling, generally in close to 50 to about 160 ° C, preferably about 70 to 120 ° C, where in each case the precise temperatures used depend, in particular on the respective conventional separator used. For example, if the propylene films are used here, the temperatures may be slightly higher than when the polyethylene films are used. If the composite is produced by lamination, the composition of the first layer may also be in partially or completely degraded form and the compound obtained after the lamination may, if required, be degraded again or otherwise used directly without the post -degradation or post-crosslinking. If the new compound is used as a separator in an electrochemical cell, the compound is combined with conventional anodes and cathodes. In addition, a dissociable compound containing lithium cations, known as a salt that increases conductivity, and if desired, other additives, such as in particular organic solvents, sometimes called electrolytes, can be incorporated. Some of all the aforementioned substances can be mixed during the production of the new compound or introduced later if it has been produced.

The salts that increase the conductivity which can be used here are well known and described, for example, in EP-A 0 096 629. The salts that increase the conductivity preferably used according to the invention are LiPF6, LiBF4, LiC104, LiAsF6, LICF3SO3, LIC (CF3S02) 3, LINE (CF3S02) 2, LiN (S02CnF2n + 1 +) 2, LIC [(CnF2n + 1) S02] 3, Li (CnF2n +?) S02, where n is in each case 2 to 20, LiN (S02F) 2, L1AICI4, LiSiF6, LiSbF6, (RS02) nXli (nX =? O, iS, 2N, 2P, 3C, 3Si; R = CmF2ra +? Where m = 0-10 or C hydrocarbons? -C20), Li imide salts, Li metide salts, or a mixture of two or more of these, and the use of LiPF6 as salts that increase the conductivity are particularly preferred. Possible organic electrolyte solvents are compounds discussed above under "plasticizers", and those preferably used are conventional organic electrolytes preferably ethers, such as ethylene carbonate, propylene carbonate, dimethyl carbonate or dimethyl carbonate, or mixtures of the compounds of this type. The thickness of the novel compounds is advantageously from 5 to 500 μm, preferably from 10 to 500 μm, more preferably from 10 to 200 μm and in particular from 15 to 100 μm.

The composite can be assembled or assembled with the anodes and cathodes to provide an electrochemical cell, which in turn is a solid composite article. This composite article advantageously has a total thickness of 30 to 2000 μm, in particular a total thickness of 50 to 1000 μm. The present invention also provides a process which produces a compound of this type and comprises the following steps: (A) producing at least a first layer as defined above; (B) producing at least a second layer as defined above; and (C) then combining at least one layer with at least one second layer, by a conventional layered separation process. It is preferably produced at least one first layer on a substrate temporarily. According to the invention, conventional temporary substrates can be used here, for example, a release film made of a polymer or a paper coated preferably, for example, a siliconized polyester film. However, this first layer can also be produced on a permanent substrate, for example a collecting electrode, or another uniform entirely without a substrate.

Upon contacting it and the production of the layer defined above takes place by means of atmospheric pressure processes to provide layers or for the production of films, such as melting or treating, or others by superatmospheric pressure processes, each extrusion, lamination , in particular hot rolling, calendering or compression. The resulting compound may, if desired, be cured or degraded by radiation or electrochemistry or thermal. It is also possible to use the process described above to produce the novel compound together with conventional electrodes and thus prepare a composite article with the constituents (release film / separator / electrode). It is also possible, the coating of two sides or double side of the compound, to provide an article composed with the constituents anode / separator / cathode. For this, the composite material, as a separator, with the anode film and / or cathode film, can be laminated together to > 80 ° C. The novel composite material here can quickly be laminated to a conventional anode or cathode, which provides a composite article - anode / - or cathode / - separator - which can then be combined with a cathode or anode to form a material compound comprising a cathode-separator-anode. An anode / separator / cathode composite article as described above can also be produced without using a substrate and, respectively, the collecting electrodes, since the new compound comprising at least a first and at least a second layer, as defined above, has per se sufficient mechanical stability for the use of electrochemical cells. The electrolyte and the salt that increases the conductivity can be placed inside the composite articles of this type or inside the electrochemical cell each before the layers are brought into contact or preferably after the layers have been put in contact. If desired after the contact has been made with suitable collector electrodes, for example, with a thin metal foil, or even after the compound, or respectively, the composite article, has been introduced into a battery cover . Here, the specific microporous structure of the layers in the novel compound, determined in particular by the presence of the solid I defined above allows the electrolyte and the salt that increases the conductivity to be absorbed with the displacement of the air in the pores. Depending on the electrode used, the load can take place from 0 to about 100 ° C. The electrochemical cells can be used in particular as a car battery, an application battery, flat battery, on-board battery, battery for static applications or electrotraction batteries. The novel compounds have the following advantages over the separators hitherto provided for use in electrochemical cells: the combination of a conventional separator and the composition containing a solid I which provides a composite material which has exceptional mechanical stability, in particular excellent dimensional stability and improved compressive strength; the novel compound can be used without difficulty in the production of a battery in commercially available extraction or winding machinery used for this purpose; - the novel compound is a separator with shutdown mechanism. Some examples will not be used to describe the present invention. EXAMPLES Example of production 1: Production of a separating film. 75 g of wollastonite are dispersed (Tremin® 800 EST, Quarzwerke Frechen) hydrophobicized with epoxysilane and with a particle size of 3 μm in 300 g of toluene using a high-speed stirrer. 12.5 g of polyethylene oxide with an average molecular weight of Mw = is added to the mixture. 2,000,000 (Polyox®, Union Carbide) and 12.5 g of a propylene oxide - ethylene oxide block copolymer (Pluriol® PE 6000, BASF AG) and 0.02 g of a UV photo-initiator (Lucirin® BDK, BASF AG), which is then applied to a film of siliconized polyethylene terephthalate at 60 ° C using a cleaner with a 300 μm molding aperture, and the toluene is removed within a period of 5 minutes, which provides a 30 μm thick film when the dried coating is peeled continuously. Production example 2: Production of a PEO adhesion layer 6 g of polyethylene oxide with an average molecular weight of Mw = 2,000,000 (Polyox®, Union Carbide) are dissolved in 300 g of toluene. The solution is cleaned inside a siliconized polyethylene terephthalate film at 60 ° C in a manner so as to provide the PEO adhesion layer with a thickness of about 3 μm. Example To produce the composite material, two films are intimately linked to each other using a model laminator Ibica IL12HR at 80 ° C. The siliconized polyethylene terephthalate film is then removed on the PEO side.

A commercially available separating film of Celgard® type 2300 (Hoechst Celanese) is then applied to the PEO adhesion layer. The two films are then joined together intimately at 80 ° C with the help of the laminator.

After cooling, the second siliconized polyethylene terephthalate film could be removed from the film of the separating compound.

Claims (10)

1. CLAIMS 1. A composite material characterized in that it comprises at least one layer which includes a composite material comprising: (a) from 1 99% by weight of a solid (I) with a primary particle size of 5 nm to 100 μm or a mixture made of at least two solids, (b) from 99 to 1% by weight of a polymer binder substance (II) which is obtained by polymerizing: b) from 5 to 100% by weight, based on the binder substance (II), of a condensation product III made from: a) at least one compound IV which is capable of reacting with a carboxylic acid or with a sulfonic acid or with a derivative or with a mixture of two or more of these, and ß) at least one mole per mole of compound IV of a carboxylic or sulfonic acid V which has at least one functional group capable of free radical polymerization, or a derivative thereof or a mixture of two or more of these and b2) from 0 to 95% by weight, based on the binder substance (II), of another compound or VII having an average molecular weight (average number) of the minus 5000 having polyether segments in a main chain or side chain, wherein at least one first layer has been applied to at least a second layer comprising at least one conventional separator .
2. 2. A composite material as claimed in claim 1, characterized in that the at least one first layer comprises a polymer binder (HA) obtainable by the polymerization b) from 5 to 75% by weight, based on a binder substance (HA). ), of a compound VI which differs from the carboxylic or sulfuric acid V and from any derivative thereof and is capable of the polymerization of free radicals, or of a mixture of two or more of these. and b2) from 25 to 95% by weight, based on the binding substance (HA), of another compound VII with an average molecular weight (average number) of at least 5000 having polyether segments in the main chain or side chain .
3. 3. A composite material as claimed in claim 1, characterized in that at least one conventional separator is selected from the class consisting of a microporous polyolefin film and a polytetrafluoroethylene film.
4. 4. A composite material as claimed in any one of claims 1 to 3, characterized in that the solid I is selected from the class consisting of an inorganic solid, selected from the class consisting of oxides, mixed oxides, silicates, sulfates, carbonates, phosphates, nitrides, amides, imides and carbides of elements of the second, 3rd, 4th main group, the 4th transition group, of the periodic table; a polymer selected from the class consisting of polyethylene, polypropylene, polystyrene, polytetrafluoroethylene and polyvinylidene fluoride; polyamides, polyimides; and a solid dispersion comprising a polymer of this type; and a mixture of two or more of these.
5. 5. A composite material as claimed in any one of claims 1 to 4, characterized in that at least one first layer comprises at least one other HIV polymer, which is selected from the class consisting of a polymer or copolymer of vinyl, acrylonitrile or vinylidene fluoride; a copolymer made of vinyl chloride and vinylidene chloride, vinyl chloride and acrylonitrile, vinylidene fluoride and hexafluoropropylene or vinylidene fluoride with hexafluoropropylene; a terpolymer made from vinylidene fluoride and hexafluoropropylene, and also a member of the class consisting of vinyl fluoride, tetrafluoroethylene and trifluoroethylene.
6. 6. A composite material as claimed in any one of claims 1 to 5, characterized in that the HIV polymer is a copolymer made from vinylidene fluoride and hexafluoropropylene.
7. 7. A separator characterized in that it comprises at least one composite material as claimed in any of claims 1 to 6.
8. 8. An electrochemical cell characterized in that it comprises a separator as claimed in claim 7.
9. 9. A process for producing a composite material as claimed in any one of claims 1 to 6, characterized in that it comprises the following steps: (A) producing at least a first layer as defined in any of claims 1 to 6; (B) producing at least a second layer as defined in any of claims 1 to 6; and (C) then combining at least one first layer with at least one second layer by means of a conventional layering process. A process as claimed in claim 6, characterized in that, by combining at least one first layer with at least one second layer, comprising at least one spacer, the at least one first layer is applied by the electrodeposition treatment partial to at least one conventional separator, or the at least one first layer is laminated, preferably hot rolled, to at least one conventional separator.