JP2013535081A - Electrode, method for producing the same, and method for using the same - Google Patents

Abstract

(A) a solid medium in which the gas can diffuse;
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer,
(D) General formula (I)
_{^{M 1 a M 2 b M 3}} c M 4 d H e O f (I)
(However, change items are defined as follows:
M ¹ is selected from Mo, W, V, Nb and Sb;
M ² is selected from Fe, Ag, Cu, Ni, Mn and lanthanoids,
M ³ is selected from B, C, N, Al, Si, P and Sn;
M ⁴ is selected from Li, Na, K, Rb, Cs, NH ₄ , Mg, Ca and Sr;
a is in the range of 1 to 3,
b is in the range of 0.1 to 10,
c is in the range of zero to 1,
d is in the range of zero to 1,
e is in the range of zero to 5,
f is in the range of 1 to 28)
At least one compound in particulate form,
And the compound of general formula (I) has a BET surface area in the range of 1 to 300 m ² / g.
[Selection figure] None

Description

The present invention
(A) a solid medium in which the gas can diffuse;
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer,
(D) General formula (I)
_{^{M 1 a M 2 b M 3}} c M 4 d H e O f (I)
(However, change items are defined as follows:
M ¹ is selected from Mo, W, V, Nb and Sb;
M ² is selected from Fe, Ag, Cu, Ni, Mn and lanthanoids,
M ³ is selected from B, C, N, Al, Si, P and Sn;
M ⁴ is selected from Li, Na, K, Rb, Cs, NH ₄ , Mg, Ca and Sr;
a is in the range of 1 to 3,
b is in the range of 0.1 to 10,
c is in the range of zero to 1,
d is in the range of zero to 1,
e is in the range of zero to 5,
f is in the range of 1 to 28)
At least one compound in particulate form,
And the compound of general formula (I) relates to an electrode characterized in that the BET surface area is in the range of 1 to 300 m ² / g.

  The invention further relates to a method of using the electrodes of the invention in electrochemical cells such as metal-air batteries, such as cadmium-air batteries, aluminum-air batteries or iron-air batteries, and in particular Zn-air batteries. The invention further relates to a method for producing the electrochemical cell of the invention and a method for producing the electrode of the invention.

  Alternatives to conventional electrochemical cells where charge transport is more or less carried out by hydrated protons and for this reason the maximum voltage is limited have been explored for many years. In this regard, an alternative storage medium for electrical energy is a lithium ion battery (charge transport is ensured by lithium ions in an aqueous solvent). However, many batteries of this type are sensitive to air and moisture, and in the worst case, cause a self-ignition of a defective lithium ion battery.

  Furthermore, it is desirable that the electrochemical cell has a high energy density.

  One remedy has been proposed by metal-air batteries, such as zinc-air batteries. In one typical embodiment, a metal, such as zinc, is oxidized by atmospheric oxygen in the presence of an alkaline electrolyte to form an oxide or hydroxide. The released energy is used electrochemically. This type of battery can be recharged by reduction of metal ions formed by discharge. For this purpose, it is known to use gas diffusion electrodes (GDEs) as cathodes. The gas diffusion electrode is porous and has a bifunctional action. The metal-air battery must be able to reduce atmospheric oxygen to hydroxide ions during the discharge process, and be able to oxidize hydroxide ions to oxygen during the charge process. I must. For this purpose, for example, a configuration in which a gas diffusion electrode is arranged on a carrier material made of finely divided (finely pulverized) carbon is known (the carrier material has a catalytic action for oxygen reduction, Or one or more catalysts for catalysis of oxygen evolution).

Here, the selection of the catalyst is very important. In this regard, pure discharge catalysts such as metal oxides such as MnO ₂ , Co ₃ O ₄ , La ₂ O ₃ , LaNiO ₃ , NiCo ₂ O ₄ , LaMnO ₃ , and LaNiO ₃ , metals such as Ag, metal complexes For example, CoTMMP (tetramethoxyphenylporphyrin) and FeTMMP-Cl, metal nitrides such as Mn ₄ N, CrN, Fe ₂ N, metal carbides such as TaC, TiC and WC, and bifunctional catalysts such as perovskites such as La _0.8 Sr _0.2 BO ₃ (Non-patent Document 1: V. Neburchilov et al., J. Power Sciences, 2010, 195, 1271) or La _0.6 Ca _0.4 Co ₃ (Patent Document 1: WO 2003/54989) A clear difference is drawn between.

Patent Document 2 (WO 2007/0656899) describes a secondary metal-air battery (wherein the active layer of the electrode includes an oxygen reduction catalyst and a dual function catalyst selected from La ₂ O ₃ , Ag ₂ O and spinel). The catalyst is disclosed.

US Pat. No. 5,318,862 discloses an electrode material consisting of a solidified mixture of graphite, NiS, FeWO ₄ and WC, which is coated with cobalt.

WO2003 / 54989 WO2007 / 0656899 US5318862

V. Neburchilov et al. , J .; Power Courses, 2010, 195, 1271

  All the materials known from the prior art cited above can still be improved with respect to at least one of the following properties: electrocatalytic activity, resistance to chemistry, electrochemical corrosion, mechanical stability. , Good adhesion to support material, and low interaction with conductive carbon black, binder, and discharge catalyst if present.

  Therefore, the electrode defined at the beginning was found.

The electrode defined above is also referred to in the present invention as an electrode of the present invention, and (A) in the present invention, a solid medium capable of diffusing a gas, also referred to as a medium (A) or a carrier (A),
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer,
(D) General formula (I)
_{^{M 1 a M 2 b M 3}} c M 4 d H e O f (I)
(However, change items are defined as follows:
M ¹ is selected from Mo, W, V, Nb and Sb;
M ² is selected from Fe, Ag, Cu, Ni, Mn and lanthanoids,
M ³ is selected from B, C, N, Al, Si, P and Sn;
M ⁴ is selected from Li, Na, K, Rb, Cs, NH ₄ , Mg, Ca and Sr;
a is in the range of 1 to 3,
b is in the range of 0.1 to 10,
c is in the range of zero to 1,
d is in the range of zero to 1,
e is in the range of zero to 5,
f is in the range of 1 to 28)
At least one particulate compound,
And the compound of general formula (I) has a BET surface area in the range of 1 to 300 m ² / g.

  The solid medium through which the gas can diffuse is also referred to in the present invention for short as medium (A) and is preferably a porous object, such as a metal, from which oxygen or air can diffuse without increasing the pressure. It is believed to be a gas diffusion medium consisting of mesh and carbon, especially activated carbon, and carbon on metal mesh. Gas permeability can be measured, for example, by the Gurley method, which is similar to measuring the gas permeability of paper or paper bonds.

In one embodiment of the present invention, the medium (A) had a porosity of, for air 10 cm ^3, a range of 20 to 1000 seconds, preferably from 40 to 120 sec / 10 cm ^3. Here, the second means “Gurley second”.

  In one embodiment of the present invention, air or atmospheric oxygen can flow through the medium (A) without being essentially disturbed.

  In one embodiment of the present invention, the medium (A) is a medium that conducts current.

  In a preferred embodiment of the invention, the medium (A) is chemically inert with respect to the reactions that proceed in the electrochemical cell under standard operation, i.e. during charging and discharging.

In one embodiment of the present invention, the medium (A) is selected from carbon having an internal BET surface area (internal BET surface area) of 20 to 1500 m ² / g (preferably referred to as an apparant BET surface area).

  In one embodiment of the present invention, the medium (A) is selected from a metal mesh such as a nickel mesh or a tantalum mesh. The metal mesh may be coarse or fine.

  In other embodiments of the invention, the medium (A) is selected from woven, matte, felt, or non-woven (which includes metal filaments).

In one embodiment of the invention, the medium is a gas diffusion medium, such as activated carbon, aluminum-doped zinc oxide, antimony-doped tin oxide, or porous carbide, or nitride, such as WC, Mo ₂ C, It is selected from Mo ₂ N, TiN, ZrN or TaC.

  The electrode of the present invention further comprises at least one conductive and carbonaceous material (B), which is also referred to as conductive carbon (B) in the present invention. The

  The conductive carbon (B) can be selected from, for example, graphite, activated carbon, carbon black, carbon nanotube, graphene, or a mixture of at least two of the above-mentioned substances.

  In one embodiment of the present invention, the conductive carbon (B) is carbon black. The carbon black may be selected from, for example, lamp black, furnace black, frame black, thermal black, acetylene black, and industrial black. Carbon black may contain impurities, such as hydrocarbons, especially aromatic hydrocarbons, or oxygen-containing compounds, or oxygen-containing groups, such as OH groups. In addition, sulfur- or iron-containing impurities can be included in the carbon black.

  When medium (A) and conductive carbon (B) are each selected as activated carbon, medium (A) and conductive carbon (B) may be chemically different, or preferably Are the same.

  The conductive carbon (B) may be present in particles having a diameter in the range of 0.1 to 100 mm, preferably in the range of 2 to 20 μm.

  In one variation, the conductive carbon (B) is a partially oxidized carbon black.

  In one embodiment of the present invention, the conductive carbon (B) includes carbon nanotubes. Carbon nanotubes (CNTs for short), such as single-walled carbon nanotubes (SW CNTs) and preferably multi-walled carbon nanotubes (MW CNTs) are known per se. The method of manufacturing these and the predetermined characteristics are described in, for example, A. Jess et al. In Chemie Ingenieur Technik 2006, 78, 94-100.

  In one embodiment of the present invention, the carbon nanotubes have a diameter in the range of 0.4 to 50 nm, preferably in the range of 1 to 25 nm.

  In one embodiment of the present invention, the carbon nanotubes have a length in the range of 10 nm to 1 mm, preferably in the range of 100 nm to 500 nm.

  Carbon nanotubes can be produced by a method known per se. For example, a volatile carbon compound, such as methane or carbon monoxide, acetylene, or ethylene, or a mixture of volatile carbon compounds, such as synthesis gas, may include one or more reducing agents, such as hydrogen, and / or additional gases, such as It can be decomposed in the presence of nitrogen. Another suitable gas mixture is a mixture of carbon monoxide and ethylene. Suitable temperatures for the decomposition are, for example, in the range from 400 to 1000 ° C, preferably in the range from 500 to 800 ° C. Suitable pressure conditions for the decomposition are, for example, in the range of standard pressure to 100 bar, preferably in the range of 10 bar.

  For example, single- or multi-walled carbon nanotubes can be obtained by decomposing a carbon-containing compound in a light arc, particularly in the presence or absence of a decomposition catalyst.

  In one embodiment, the decomposition of one or more volatile carbon-containing compounds is performed in the presence of a decomposition catalyst such as Fe, Co or preferably Ni.

  In the present invention, graphite means almost ideal or ideal (having a structure similar to a single graphite layer) carbon two-dimensional hexagonal crystal.

In one embodiment of the invention, the conductive carbon (B) and in particular carbon black has a BET surface area in the range of ²⁰ to 1500 m ² / g as measured according to ISO 9277.

  The electrode of the present invention comprises at least one organic polymer, which is referred to as polymer (C) or abbreviated as binder (C). In this regard, the term “organic polymer” also includes organic copolymers, and the main chain is predominantly, ie containing at least 50 mol%, carbon atoms, and radical polymerization, anionic, cationic polymerization, or polyaddition, or polyaddition. It means a polymeric compound that can be produced by condensation.

  Particularly suitable polymers (C) are, for example, (co) polymers obtained by anion, catalyst or radical (co) polymerization, in particular polyethylene, polyacrylonitrile, polybutadiene, polystyrene, polyethyleneimine, and ethylene, propylene, styrene, ( It may be selected from a copolymer of at least two comonomers selected from met) acrylonitrile and 1,3-butadiene. Polypropylene is also suitable. Polyisoprene and polyacrylate are additionally suitable. Polyacrylonitrile is particularly preferred.

  For the purposes of the present invention, polyacrylonitrile is understood to mean not only polyacrylonitrile homopolymers but also copolymers of acrylonitrile and 1,3-butadiene or styrene.

For the purposes of the present invention, polyethylene means not only homopolyethylene but also at least 50 mol% of copolymerized ethylene and up to 50 mol% of at least one further comonomer such as an α-olefin such as propylene, butylene ( 1-butene), 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-pentene, and isobutene, vinyl directional group compounds such as styrene, and (meth) acrylic acid, vinyl acetate, vinyl propinate, C ₁ -C ₁₀ of (meth) acrylic acid - alkyl ester, in particular methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n- butyl acrylate, 2-ethylhexyl acrylate, n- butyl methacrylate, 2-ethylhexyl methacrylate,及Maleic acid is understood to mean also the ethylene copolymer comprising maleic anhydride, and itaconic anhydride. The polyethylene may be HDPE or LDPE.

  For the purposes of the present invention, polypropylene is not only understood to mean homopolypropylene, but also at least 50 mol% of copolymerized propylene and up to 50 mol% of at least one further comonomer such as ethylene and α-olefins. Is also understood to mean copolymers comprising, for example, butylene, 1-hexene, 1-octene, 1-decene, 1-dodecene and 1 pentene. The polypropylene is preferably isotactic or essentially isotactic polypropylene.

For the purposes of the present invention, polystyrene means not only a homopolymer of styrene, but also acrylonitrile, 1,3-butadiene, (meth) acrylic acid, (meth) acrylic acid C ₁ -C ₁₀ -alkyl esters, divinylbenzene, In particular, it is understood to mean copolymers with 1,3-divinylbenzene, 1,2-diphenylethylene and α-methylstyrene.

  Another preferred binder (polymer (c)) is polybutadiene.

  Other suitable polymers (C) are selected from polyethylene oxide (PEO), cellulose, carboxymethyl cellulose, polyimide, and polyvinyl alcohol.

In one embodiment of the invention, the polymer (C) is selected from these (co) polymers having an average molecular weight M _{w in} the range of 50,000 to 1,000,000 g / mol, preferably ˜500,000 g / mol.

  The polymer (C) may be a crosslinked or non-crosslinked (co) polymer.

  In a particularly preferred embodiment of the invention, the polymer (C) is selected from halogenated (co) polymers, in particular fluorinated (co) polymers. Halogenated or fluorinated (co) polymers are at least 1 halogen atom per molecule, or at least 1 fluorine atom, preferably at least 2 halogen atoms per molecule, or at least 2 It is understood to mean these (co) polymers comprising at least one (co) polymerized (co) monomer having a fluorine atom.

  Examples are polyvinyl chloride, polyvinylidene chloride, polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer (PVdF-HFP), vinylidene fluoride tetrafluoroethylene copolymer Perfluoroalkyl vinyl ether copolymers, ethylene tetrafluoroethylene copolymers, vinylidene fluoride-chlorotrifluoroethylene copolymers, and ethylene-chlorofluoroethylene copolymers.

  Suitable polymers (C) are in particular polyvinyl alcohol and halogenated (co) polymers such as polyvinyl chloride or polyvinylidene chloride, in particular fluorinated (co) polymers such as polyvinyl fluoride, and in particular polyvinylidene fluoride, And polytetrafluoroethylene.

The electrode of the present invention further has the general formula (I)
_{^{M 1 a M 2 b M 3}} c M 4 d H e O f (I)
(However, change items are defined as follows:
M ¹ is selected from Mo, W, V, Nb and Sb, preferably V, Mo and W;
M ² is selected from Fe, Ag, Cu, Ni, Mn and lanthanoids, preferably La and Ce among Fe, Ag and lanthanoids;
M ³ is selected from B, C, N, Al, Si, P and Sn, preferably P and Si;
M ⁴ is selected from Li, Na, K, Rb, Cs, NH ₄ , Mg, Ca and Sr, preferably NH ₄ , Li, K and Na;
a is in the range of 1 to 3, preferably 1,
b is in the range of 0.1 to 10, preferably in the range of 0.3 to 3,
c is in the range of zero to 1, preferably in the range of ~ 0.2;
d is in the range of zero to 1, preferably in the range of -0.2;
e is in the range of zero to 5, preferably in the range of -1.0;
f is in the range of 1 to 28)
At least one compound in a particulate state, also referred to as compound (D) for short,
And the compound of general formula (I) has a BET surface area in the range of 1 to 300 m ² / g, preferably in the range of 1 to 100 m ² / g, more preferably in the range of 1 to 50 m ² / g. .
In one embodiment of the invention, the variable f is chosen such that compound (D) is electrically uncharged.

  In one embodiment of the invention, the variable f is chosen such that compound (D) is not electrically uncharged (eg, less than zero to -2).

  When the variable e is chosen so that it is not zero, preferably hydrogen is present in the hydroxide ions in the compound (D).

In one embodiment of the present invention, M ¹ , M ² , M ³ or M ⁴ in the compound (D) is selected from a mixture of at least two elements. For example, M ² is selected from a mixture of Fe and Ag. For example, M ¹ is selected from a mixture of V and Mo.

  In one embodiment of the invention, compound (D) is selected from mixed oxides and heteropolyacids and their salts, such as ammonium or alkali metal salts. The compound (D) is preferably selected from mixed oxides.

  In one embodiment of the present invention, the compound (D) is composed of Fe—Ag—X—O, Fe—V—X—O, Ag—V—X—O, Ce—X—O and Fe—X—. Selected from O, wherein X is selected from tank stainless and preferably molybdenum.

In one embodiment of the present invention, Fe—Ag—X—O in compound (I) is represented by the general formula (II)
_{X a Fe b1 Ag b2 O f} (II)
(However, the sum of the variables b1 to b2 is in the range of 0.1 to 10, preferably in the range of 0.3 to 3, and the remaining variables are as described above.)
Selected from the following compounds:

In one embodiment of the invention, Fe—V—X—O has the general formula (III)
_{V a1 X a2 Fe b O f} (III)
(However, the sum of the variables a1 and a2 is in the range of 1-3, and preferably 1, and the other variables are defined above)
Selected from the following compounds:

In one embodiment of the invention, Ag—V—X—O is represented by the general formula (IV)
_{V a1 X a2 Ag b O f} (IV)
(However, the variables are those defined above.)
Selected from the following compounds:

In one embodiment of the present invention, Ce—X—O is represented by the general formula (V)
_{X a Ce b O f (V} )
(However, the variables are those defined above.)
Selected from the following compounds:

  Compound (D) is in the state of particles. In this case, the particles may be regular or irregular shapes and may be, for example, spherical, plate-like, needle-like, or irregularly shaped.

  In one embodiment of the present invention, the compound (D) has an average primary particle size in the range of 10 to 50 nm. The average primary particle diameter can be measured by a microscope, for example, a scanning electron microscope or a transmission electron microscope (TEM).

  In one embodiment of the present invention, the compound (D) is in the form of aggregated particles, and in this case, the aggregate may have an average diameter of 20 nm to 100 μm. In this case, the aggregate (lumps) may have an appearance in which the particles of the compound (D) may be composed of, for example, at least 2 to several thousand primary particles.

In one embodiment of the present invention, the compound (D) has a BET surface area in the range of 1 to 300 m ² / g as measured by ISO9277.

  In one embodiment of the present invention, the compound (D) has a bimodal distribution in particle size.

  In one embodiment of the invention, the electrode of the invention comprises a mixture of at least two different compounds (D).

In one embodiment of the present invention, the electrode of the present invention is based on the entire electrode,
Conductive carbon (B) in the range of 20 to 50% by mass, preferably in the range of 35 to 45% by mass,
A polymer (C) in the range of 5-45% by weight, preferably in the range of 30-40% by weight, and a compound (D) in the range of 0.5-25% by weight, preferably in the range of 5-15% by weight;
including.

  In one embodiment of the invention, the electrode of the invention further comprises at least one discharge catalyst (E).

Examples of suitable discharge catalysts (E) are, for example, La ₂ O ₃ , Ag ₂ O, spinels such as LiMn ₂ O ₄ , MnO ₂ , Ag, CoTMMP (cobalt tetra [para-methoxyphenyl] porphyrin), FeTMMP- Cl, Mn ₄ N, CrN, Fe ₂ N, TaC, TiC, WC, Co ₃ O ₄ , La ₂ O ₃ , LaNiO ₃ , NiCo ₂ O ₄ , LaMnO ₃ , LaNiO ₃ , especially Ag and Ag / C .

  The discharge catalyst (E) is preferably in a particulate state. In this case, the particles may have a regular or irregular shape and may be, for example, a spherical shape, a plate shape, a needle shape, or an irregular shape. The average diameter of the discharge catalyst particles may be in the range of 2 nm to 100 μm. In the present invention, Ag particles, which may be referred to as Ag particles, may have, for example, an average diameter in the range of 2 to 200 nm, preferably in the range of 10 to 50 nm. If it is desired to use Ag on carbon as the discharge catalyst, the Ag particles may have a diameter in the range of 2 to 200 nm, and the carbon particles have a diameter in the range of 0.1 to 100 μm. May be.

  In an embodiment in which the electrode of the present invention includes at least one type of discharge catalyst (E), the electrode of the present invention is 0 with respect to the total of conductive carbon (B), polymer (C) and compound (D). 5 to 80% by mass of the discharge catalyst (E).

  In a preferred embodiment in which the electrode of the present invention contains Ag particles as the discharge catalyst (E), the electrode of the present invention is based on the total of conductive carbon (B), polymer (C) and compound (D), 0.5 to 15% by mass, preferably 2 to 6% by mass of the discharge catalyst (E) is contained.

  In a preferred embodiment in which the electrode of the present invention contains Ag particles on carbon as the discharge catalyst (E), the electrode of the present invention is a total of conductive carbon (B), polymer (C) and compound (D). On the other hand, it contains 10 to 80% by mass, preferably 25 to 50% by mass of the discharge catalyst (E).

  In one embodiment of the invention, the electrode of the invention may contain further components. Suitable further components are, for example, organic solvents, in particular solvents which are understood to mean isopropanol, N-methylpyrrolidone, N, N-dimethylacetamide, amyl alcohol, n-propanol or cyclohexanone. Furthermore, suitable solvents are organic carbonates, cyclic or acyclic, such as diethyl carbonate, ethylene carbonate, propylene carbonate, dimethyl carbonate and ethyl methyl carbonate, and organic esters, cyclic or acyclic, For example methyl formate, ethyl acetate or γ-butyrolactone (gamma-butyrolactone) and also ether, cyclic or acyclic, for example 1,3-dioxolane.

  Furthermore, the electrode of the present invention may contain water.

  The electrode of the present invention may be configured in various forms. For example, when the carrier (A) is selected from a metal mesh, the shape of the electrode of the present invention can be basically defined by the shape of the metal grid.

  Further, in the case where the carrier (A) is selected from activated carbon, in the case of activated carbon that has been refined (pulverized) (for example, the average particle size is 0.1 to 100 μm), the electrode is It can be applied as a formulation, eg a paste or paste, on a metal mesh, a gas diffusion medium composed of carbon, or a gas diffusion layer composed of carbon on a metal mesh.

  The present invention further provides the electrode of the present invention to an electrochemical cell, for example, a non-rechargeable electrochemical cell (also referred to as a primary battery) or a rechargeable electrochemical cell (also referred to as a secondary battery). Provide a method to use. The present invention further provides a method for producing an electrochemical cell using at least one electrode of the present invention. The present invention further provides an electrochemical cell comprising at least one electrode of the present invention.

  In a preferred embodiment of the present invention, the electrochemical cell of the present invention comprises a Cd-air battery, an Fe-air battery, an Al-air battery, or a zinc-air battery.

  The electrochemical cell of the present invention may have further components, such as a housing and at least one counter electrode, which may be of any shape, in particular a cylinder, a disk, or a cuboid. The counter electrode comprises as an essential component an elemental metal such as Fe, Al, Cd or in particular zinc.

  The elemental metal may be in the form of a calcined porous electrode, or optionally a calcined metal powder, or a solid slab of pellets. In one embodiment, the metal is in the elemental state as a powder, especially zinc, having an average particle size (number average) in the range of, for example, 2 μm to 500 μm, preferably in the range of 30 to 100 μm.

  In one embodiment, the powdered metal is mixed with an organic binder to improve dimensional stability. Suitable organic binders are polysulfones, polyether sulfones, and especially fluorinated (co) polymers such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF).

  In a preferred embodiment, powdered metal, especially powdered zinc, is used as a paste or paste with an organic binder.

  The electrochemical cell of the present invention further includes at least one separator that mechanically separates the differently charged electrodes from each other and thus prevents short circuits. Suitable separators are polymer films, particularly porous polymer films, that are non-reactive with elemental metals and typically strongly basic media within the electrochemical cells of the present invention. Particularly suitable materials for the separator are polyolefins, in particular porous polyethylene films, and porous polypropylene films.

  The polyolefin separator, particularly polyethylene or polypropylene separator, may have a porosity in the range of 35-45%. A suitable pore size is, for example, in the range of 30 to 500 nm.

  In another embodiment of the invention, the separator can be selected from PET nonwovens filled with base-stable inorganic particles. Such separators may have a porosity in the range of 40-55%. A suitable pore size is, for example, in the range of 80 to 750 nm.

  In order to produce the electrochemical cell of the present invention, the procedure, for example, couples the electrode, separator, and counter electrode of the present invention together and introduces them into the housing along with (optional) further components. It can be a thing.

  The electrochemical cell of the present invention may further comprise at least one electrolyte (which is at least one solvent and at least one salt-like compound, or a combination of salts). Examples of suitable electrolytes are in particular aqueous bases such as sodium hydroxide solution or potassium hydroxide solution.

  In one embodiment of the invention, the electrochemical cell of the invention may comprise a further electrode, for example as a reference electrode. A suitable further electrode is, for example, a zinc wire.

The present invention further provides a method for producing the electrode of the present invention (hereinafter, this method is also referred to as the production method of the present invention). In order to perform the manufacturing method of the present invention, the procedure is as follows:
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer, and (D) at least one compound of general formula (I) in a particulate state and having a BET surface area in the range of 1 to 300 m ² / g,
In one or more steps,
(A) It may be applied to a solid medium in which gas can diffuse.

This procedure is especially
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer, and (D) at least one compound of general formula (I) in a particulate state and having a BET surface area in the range of 1 to 300 m ² / g,
In the form of an aqueous or solvent-based ink, or preferably an aqueous paste, or preferably an aqueous dough,
(A) The gas may be applied to a solid medium in which gas can be diffused.

  The compounds of formula (I) are those described above. The remaining variables (change items) are the same as those described above.

  It is also possible for compound (D) to be first treated, for example coated with conductive carbon (B) and then mixed with polymer (C) and applied to support (A).

  Application (application) can be effected, for example, by spraying, for example spraying or atomization, and knife coating, printing or pressing. In the present invention, nebulization also includes application using a spray gun, a method also referred to as “airbrushing” or “airbrushing” for short.

  Implementation of the production method of the present invention begins with, for example, one or more compounds (D).

Compound (D) is prepared, for example, by mixing suitable compounds of M ¹ , M ² and optionally M ³ and / or M ⁴ , for example in the dry state or as a solution or suspension. (Preparation). The proportion of M ¹ , M ² , and optionally M ³ and / or M ⁴ compounds in the stoichiometry of M ¹ , M ² , optional M ³ and M ⁴ in compound (D) It is preferable to select. The mixture thus obtained is then thermally treated; for example it can be calcined, for example in the range of 250-1000 ° C., preferably in the range of 300-800 ° C. Calcination can be carried out under an inert gas or under an oxidizing atmosphere, for example under air (or under a mixture of inert gas and oxygen). The duration of calcination may be several minutes to several hours.

Suitable starting materials useful for preparing the compound (D) include oxides of ^{M 1, M 2, M 3} , and / or M ^4, hydroxides, or oxohydroxide. Further, such useful compounds of M ¹ , M ² , M ³ , and / or M ⁴ may react as a result of heating in the presence or absence of oxygen to produce oxides, hydroxides or Oxohydroxide is produced.

  The starting materials can be mixed to produce compound (D) in a dry or wet state. If it is desired to carry out in the dry state, the starting material for preparing compound (D) can be used in fine powder form and after mixing and optional compaction, calcining Made. However, intimate mixing in the wet state is preferred. Typically, this involves mixing the starting materials with one another in the form of an aqueous solution and / or aqueous suspension to produce compound (D).

A particularly good mixture of starting materials for the preparation of compound (D) starts exclusively from dissolved M ¹ , M ² , M ³ , and / or M ⁴ compounds, and M ¹ , M ² , It can be obtained by precipitating M ³ and / or M ⁴ compounds. The aqueous material obtainable in this way is then preferably dried at a temperature in the range from 100 to 150 ° C. A very preferred drying method is spray drying, in particular with an outlet temperature in the range of 100-150 ° C.

  Before, during and preferably after the heat treatment, steps for obtaining the desired particle size of the compound (D) can be carried out, for example sieving, crushing or classification.

  In any step, compound (D) can be treated with conductive carbon (B), for example, coated. In order to perform such treatment, for example, the compound (D) can be strongly mixed with the conductive carbon (B), for example, these can be pulverized (ground). For example, a mill, in particular a ball mill, is suitable for powdering.

  In other variations of any treatment of compound (D) with conductive carbon (B), carbon can be deposited on compound (D) (eg, by decomposing organic compounds).

  This is then mixed with the polymer (C) which can be added (for example in the form of an aqueous dispersion or pellets).

  In other embodiments, compound (D), conductive carbon (B), and polymer (C) (which can be added, for example, in the form of an aqueous dispersion or pellet) in one step, for example, the corresponding solid, optionally Are mixed by stirring using one or more organic solvents or water. For mixing, for example, stirring devices, such as stirring tanks, or mills, such as ball mills, and in particular stirring ball mills, can be used. In other embodiments, for example, ultrasound using sonotrode is used. This preferably results in an aqueous formulation.

  The desired properties of the applied formulation are then set (eg viscosity or solid content), preferably aqueous.

  In the present invention, preferably aqueous formulations having a solids content of 0.5-25% are referred to as inks. A preferably aqueous formulation with a solids content above 25% is referred to as a paste.

  In one embodiment of the invention, preferably the aqueous formulation comprises at least one surfactant. In the present invention, the surfactant is a surface active (surface active) substance. The surfactant can be selected from cationic, anionic, and preferably nonionic surfactants.

  Next, a medium (A) or a carrier (A) is prepared, which includes one type (including conductive carbon (B), polymer (C), compound (D), and any discharge catalyst (E)). The above preferably aqueous formulations are applied in one or more steps. This supply (application) can be effected, for example, by pressing, spraying, in particular spraying with a spray gun, and knife coating, or preferably printing.

  In another embodiment of the invention, a mixture of conductive carbon (B), polymer (C), compound (D), and optionally discharge catalyst (E), which does not have a solvent, is optionally used, for example 30-300 bar. And a pressure in the range of 150-320 ° C. For this purpose, one can start with a paste, preferably an aqueous paste, whose layer height can be adjusted using a shim by rolling or cutting to a predetermined dimension, and this is the medium ( A) is applied (supplied).

  Following this feeding (fixing), the fixing is carried out, for example, by a heat treatment, in particular at a temperature of 150 to 350 ° C., in particular at a temperature approximately corresponding to the glass transition temperature of the polymer (C). In this case, when a vinylidene fluoride hexafluoropropylene copolymer is selected as the polymer (C), the temperature is preferably selected in the range of, for example, 125 to 175 ° C, preferably about 150 ° C. In other variations, the selected temperature is 175 to 225 ° C, preferably about 200 ° C, and the polymer (C) selected is polyvinylidene fluoride. In other variations, the selected temperature is 300-350 ° C, preferably 320-325 ° C, and the selected polymer (C) is polytetrafluoroethylene.

  In a variant, it can be fixed mechanically, for example by calendaring.

  This provides the electrode of the present invention, which can be combined with further components to provide the electrochemical cell of the present invention.

  As a result, the electrochemical cell of the present invention having comprehensively very good characteristics can be obtained.

Other aspects of the invention include at least one organic solvent, or water, and (B) at least one conductive, carbonaceous material,
(C) at least one organic polymer, and (D) molybdenum or tungsten, and at least one mixture comprising at least one element (selected from Fe, Ag, lanthanoids and V),
(For short, also referred to as the formulation of the present invention).

  Aqueous formulations are preferred.

  Conductive carbon (B), polymer (C) and compound (D) are defined above.

  In one embodiment of the invention, the preferably aqueous formulation of the invention comprises at least one further ingredient selected from surfactants, thickeners and antifoaming agents.

  In one embodiment of the present invention, the preferably aqueous formulation of the present invention has a solids content in the range of 0.5-60%.

  The present invention will be described below using examples.

  General prior note: In the present invention, percentage figures represent mass percent unless otherwise stated.

I. Preparation of aqueous formulations 1 Preparation of aqueous ink, WF1.1 In a stirred vessel, a magnetic stirrer was used to mix 2 g of ethoxylated trimethylnonyl alcohol and 66.5 g of water. Next, 0.4 g NiS, 0.4 g WC, and 1 g FeAgMo ₂ O ₈ (D.1), a BET surface area of 1.5 m ² / g, and 3 g of activated carbon (on C) 9% Ag) (B.1) was added with stirring. It was then dispersed using ultrasound with the following procedure: 14 mm US sonotrode, cycle 1, amplitude 45%, 8 ° C. cooling, magnet stirrer 75%, energy input below 0.025 kWh. Next, 3.8 g of an aqueous dispersion (C.1) of polytetrafluoroethylene with a solid content of 60% was added and the mixture was stirred for 15 minutes without further sonication. This mixture was filtered through a 190 μm screen to obtain the ink of the present invention (this ink is hereinafter also referred to as WF1.1).

I. 2 Preparation of water-based ink, WF1.2 Using a magnetic stirrer, 2 g of ethoxylated trimethylnonyl alcohol and 66.5 g of water were mixed in a stirring vessel. Next, 0.4 g of NiS, 0.4 g of WC, and 0.4 g of Fe ₂ (WO ₄ ) ₃ (D.2), BET surface area of 3 m ² / g, and 3 g of activated carbon of Ag. (9% Ag on C) (B.1) was added with stirring. It was then dispersed using ultrasound with the following procedure: 14 mm US sonotrode, cycle 1, amplitude 45%, 8 ° C. cooling, magnet stirrer 75%, energy input below 0.025 kWh. Next, 3.8 g of an aqueous dispersion (C.1) of polytetrafluoroethylene with a solid content of 60% was added and the mixture was stirred for 15 minutes without further sonication. This mixture was filtered through a 190 μm screen to obtain the ink of the present invention (this ink is hereinafter also referred to as WF1.2).

II. Application (application) of the aqueous formulation WF1.1 or WF1.2 of the present invention and production of the electrode of the present invention The carrier (A.1) used is a metal mesh, and one side of the metal mesh is (B. 1) / (C.1) It was coated with a mixture. The coated metal mesh was 400 μm with the coating and the air permeability was 90 Gurley seconds per 10 cm ³ .

Next, using a spray gun (using nitrogen for spraying), the aqueous formulation WF. 1 was sprayed onto a vacuum table having a temperature of 75 ° C. This gave a load of 10-25 mg / cm ² (calculated based on the sum of (B.1), (C.1) and (D.1)).

This was followed by a calendar process using a calendar with the following calendar settings:
Roll temperature at a pressure of ² N / mm ² and a forward speed of 100 ° C. at a pressure of 0.5 m / min. At this temperature, polytetrafluoroethylene softened.

  Thereby, the electrode of the present invention, electr. 1 was obtained.

III. Production and Testing of the Electrochemical Cell of the Invention The electrode of the invention had an open circuit potential of 1.35 to 1.5 volts. During discharge, the cell voltage dropped to 1.2-1.25 volts with a discharge current of 20 mA / cm ² . During the charging operation, the cell voltage increased to a value of 1.95 to 2.00 V at a current density of 20 mA / cm ² . At higher current densities, for example 50 mA / cm ² , the voltage during discharge was 1.1 to 1.15 volts. For discharge operation, a voltage of 2.00 to 2.05 V was observed at a current density of 50 mA / cm ² . The electrode of the present invention achieved more than 100 cycles in an electrochemical test cell (half cell).

Claims (17)

(A) a solid medium in which the gas can diffuse;
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer,
(D) General formula (I)
_{^{M 1 a M 2 b M 3}} c M 4 d H e O f (I)
(However, change items are defined as follows:
M ¹ is selected from Mo, W, V, Nb and Sb;
M ² is selected from Fe, Ag, Cu, Ni, Mn and lanthanoids,
M ³ is selected from B, C, N, Al, Si, P and Sn;
M ⁴ is selected from Li, Na, K, Rb, Cs, NH ₄ , Mg, Ca and Sr;
a is in the range of 1 to 3,
b is in the range of 0.1 to 10,
c is in the range of zero to 1,
d is in the range of zero to 1,
e is in the range of zero to 5,
f is in the range of 1 to 28)
At least one compound in particulate form,
And the compound of general formula (I) has a BET surface area in the range of 1 to 300 m ² / g.   The electrode according to claim 1, wherein the compound (D) is selected from an oxide mixture, a heteropolyacid, and a salt thereof.   Compound (D) is selected from Fe—Ag—X—O, Fe—V—X—O, Ag—X—V—O, Ce—X—O, and Fe—X—O, and X is The electrode according to claim 1 or 2, wherein the electrode is selected from molybdenum and tungsten.   The electrode according to any one of claims 1 to 3, wherein the organic polymer (C) is selected from halogenated (co) polymers.   The electrode according to any one of claims 1 to 4, wherein the solid medium (A) is selected from a metal mesh and a gas diffusion medium composed of carbon. The electrode according to claim 1, wherein the conductive and carbonaceous material (B) has a BET surface area in the range of ^{20 to} 1500 m ² / g.   The electrode according to any one of claims 1 to 6, wherein the compound (D) has an average primary particle diameter in the range of 10 to 50 nm.   The electrode according to any one of claims 1 to 7, wherein the compound (D) is in a state of aggregated particles, and the aggregate has an average diameter of 20 nm to 50 µm.   Furthermore, a discharge catalyst is included, The electrode of any one of Claims 1-8 characterized by the above-mentioned.   The method to use the electrode of any one of Claims 1-9 in an electrochemical cell.   11. The method of claim 10, wherein the electrochemical cell comprises a cadmium-air battery, an aluminum-air battery, an iron-air battery, or a zinc-air battery.   An electrochemical cell comprising at least one electrode according to claim 1.   A method of operating a device using the electrochemical cell according to claim 12. A method for producing the electrode according to claim 1, comprising:
(B) at least one conductive and carbonaceous material;
(C) at least one organic polymer, and (D) at least one compound of general formula (I) in a particulate state and having a BET surface area in the range of 1 to 300 m ² / g,
But in one or more steps,
(A) A method comprising applying a gas to a diffusible solid medium. (B) at least one conductive and carbonaceous material;
(C) at least one organic polymer, and (D) at least one compound of general formula (I) in a particulate state and having a BET surface area in the range of 1 to 300 m ² / g,
Is in the state of ink, paste or dough,
15. The method of claim 14, wherein (A) the gas is applied to a diffusible solid medium.   The method according to claim 14 or 15, wherein the heat treatment is performed after the gas is applied to the solid medium capable of diffusing. At least one organic solvent, or water, and (B) at least one conductive and carbonaceous material,
(C) at least one organic polymer, and (D) general formula (I)
_{^{M 1 a M 2 b M 3}} c M 4 d H e O f (I)
(However, change items are defined as follows:
M ¹ is selected from Mo, W, V, Nb and Sb;
M ² is selected from Fe, Ag, Cu, Ni, Mn and lanthanoids,
M ³ is selected from B, C, N, Al, Si, P and Sn;
M ⁴ is selected from Li, Na, K, Rb, Cs, NH ₄ , Mg, Ca and Sr;
a is in the range of 1 to 3,
b is in the range of 0.1 to 10,
c is in the range of zero to 1,
d is in the range of zero to 1,
e is in the range of zero to 5,
f is in the range of 1 to 28)
At least one particulate compound,
And the compound of general formula (I) has a BET surface area in the range of 1 to 300 m ² / g.