WO2018109150A1

WO2018109150A1 - Electrode material, method for producing electrodes, and said electrodes and electrochemical cells

Info

Publication number: WO2018109150A1
Application number: PCT/EP2017/082978
Authority: WO
Inventors: Lorenz Walder; Seyyed Mohsen BELADI MOUSAVI
Original assignee: Universität Osnabrück
Priority date: 2016-12-16
Filing date: 2017-12-15
Publication date: 2018-06-21
Also published as: EP3563440A1; DE102016124586A1

Abstract

In a first aspect, the present invention is directed to an electrode material, wherein the latter is embodied in the form of a colloidal solution of a molecular complex comprising nanoscale redox-active organic oligomer and/or polymer and at least nanoscale graphitic material. Furthermore, a method for producing electrodes is provided, as are corresponding electrodes. Moreover, the present invention relates to electrochemical cells comprising electrodes according to the invention and/or electrode material according to the invention. Finally, a method for producing redox-active organic oligomers and/or polymers is described.

Description

In a first aspect, the present invention is directed to an electrode material, in particular for accumulators, which first in the form of a colloidal precursor solution of a molecular complex of nanoscale redoxaktive organic oligomer and / or polymer and at least nanoscale graphitic material is formed. In addition, a method for producing electrodes with activation of the precursor product is provided, as well as corresponding electrodes, in particular for accumulators. Furthermore, the present invention relates to electrochemical cells, in particular accumulators with electrodes according to the invention and / or electrode material according to the invention.

Finally, a process for the preparation of redox-active organic oligomers and / or polymers is described.

State of the art

Mobility and information exchange are increasingly shaping the life of modern society. Therefore, more and more efficient, rechargeable, portable batteries and accumulators are inevitably needed. High gravimetric and / or volumetric energy and / or power density and stability over many charge / discharge cycles are required. By way of example, it is expected that a smartphone will run for several days without having to recharge it, that is to say a high volumetric and gravimetric energy density of the accumulator. The battery pack of an electric car should guarantee a range of at least 500 kilometers, this requires a high energy and power density and the battery should also be fast, such as in a few minutes, rechargeable, which requires a high power density. For example, a To keep a drone in flight for more than an hour requires the cells used, ie the batteries / accumulators a high power and energy density.

Moreover, in the future, the external shape of the battery should be able to be adapted to given external shapes, for example be woven or incorporated into fabrics of clothing, or be integrated into the bracelet of a smartwatch or the like. That is, a flexibility of the accumulators is provided. In addition to energy and power density, recyclability, degradability, for example by composting, but also a reduction in the toxicity, in the present case of the heavy metal content and explosion safety, play an increasingly important role, especially in the case of large production numbers.

Regarding their construction and their function related to the accumulators are the supercapacitors which are partly also constructed of graphene and store the charge purely capacitive or mixed capacitive-electochemical. Compared to the accumulators, they have a lower energy density, but an increased power density, supercapacitors are used in applications to provide high power in the short term. Supercapacitors differ from batteries in that they store the charge at least partially electrostatically (capacitively) on a large, advantageously nanoscopically enlarged, conductive surface and that this charge is compensated by counter ions from the solution, while in batteries the charge is stored on redox-active centers which are advantageously in electrical contact with a similar nanoscopic current collector as in the supercapacitor. While in supercapacitors the charge / discharge process takes place over a wide voltage range, the charge / discharge in the battery takes place in a narrow potential range. The supercapacitors, in contrast to the accumulators described here, do not provide a constant operating voltage. Their output voltage (U) is linearly dependent on the charge state (Q) (U = Q / C). For the batteries, the output voltage depends only on the logarithm of the state of charge (the voltage of a battery changes only by 59 mV when the battery is discharged from 90% to 10%, according to the Nernst equation). Many electronic circuits require a constant operating voltage. When using supercapacitors, this can only be achieved by using additional electronic measures (so-called DC-DC converters). This is associated with additional weight and volume baiast. Zhu Y, et al., J. Power Sources, 2014, 268, 233 describes polypyrrole coated carbon structures for supercapacitors.

In principle, all anode / cathode systems are subsumed under the term LIBs (Lithium Ion Batteries) with two surface-anchored lithium-ion intercalation systems. Usually, this term is understood to mean the lithium ion batteries on the market. These dominate the modern accumulator market due to their high energy density, their high cyclability and their relatively high user-friendly handling in various variations. The standard anode of such LIBs is based on a (de) intercalation of Li ⁺ in graphite, corresponding to a potential which practically corresponds to the potential of the Li7 lithium half-cell. As a result, it has a negative potential of about -3V against a SHE (standard hydrogen electrode), the gravimetric capacity is about 350 mAh / g and the average volumetric capacity is between 330 to 430 mAh / cm ³ . The area-specific capacity is between 3 to 4 mAh / cm ² , thereby making it an ideal anode material.

The cathode in such a system is based on the reversible (de) intercalation of lithium ions in crystalline metal oxides and phosphates. Here is currently the most improvement potential seen. We are looking for materials with high volume-, mass-specific and area-specific energy and power density. Conventionally, materials of the type L1MO2 have been used to date, with M being nickel, cobalt and / or manganese. These deliver capacities of around 180 mAh / g, recently describing a vanadium oxide cathode capable of up to 400 mAh / g, but exhibiting variable discharge voltage and poor cyclability.

In general, these lithium ion batteries with a graphite anode and a L1MO2 cathode cell voltage of> 3V, but this undesirable side reactions and a considerable hazard potential (explosion safety) occur.

A large area-specific charge (current density) in such LIB cathode materials is limited by the low ion and electrode conductivity in the intercalation grid and between the crystals. This limitation and overcoming of this is currently the subject of intensive research. To circumvent the diffusion of lithium ions and electrons into and out of the cathodic host crystal, for example, small crystals are used, but their synthesis is expensive. To improve the ion and electrode conductivity between the host crystals, graphitic micro- and nanomaterials are added. Pressing these nano- and microcomponents, that is the host crystals and graphic material in the presence of binders, results in a porous composite material with electrolyte and electrode percolation system, but this does not result in any molecular contact between the electrical conductor and the charge storage material there is no adequate connection between the various components.

Such systems are usually present in a ratio of active material: Electrode conductor: binder in percentages by weight of a maximum of 75:50:10. Although the addition of graphitic material increases the specific current density (mA / cm ² ), it reduces the surface and area-specific capacitance (mAh / gcm ² ) relative to its own weight. Solving this problem of conflicting requirements is the subject of much research. Typical values for such systems are, for example, energy densities of 150 to 100 mA / g, with a maximum

Layer thickness of about 100 μιτι, wherein about 1 to 4 mAh / cm ² at maximum current densities of 5 to 8 mA cm ² .

Thus, for example, WO 2014/093876 A1 describes a semisolid electrode material having a high capacitance, the cathodic materials have layer thicknesses of up to several 100 μm, specific capacitances of up to 12 mA / cm ² and current densities of up to 10 mA / cm ² without capacity loss and up to 16 mA / cm ² with a 50 percent capacity loss.

However, the LIBs based on aqueous systems have the problem that due to the thermodynamically possible evolution of hydrogen and oxygen and the associated risk of explosion, no large cell voltages can be realized. Organic solvents are necessary but have other disadvantages, such as smaller ionic conductivity and high flammability.

Corresponding problems often occur with lithium anodes. Although alternative anode materials are compatible with aqueous electrolytes (for example, T1O2), they do not have sufficient capacity and are insufficient

Charge / discharge cycle number while reducing the cell voltage. As already stated, flexibility in batteries is also desirable. However, there is no flexibility in crystalline material due to the cathodes used by the LIBs. An attempt is made to produce flexible batteries by using thin layers of host crystals on a flexible current collector, but these have limited performance characteristics.

Crystalline ceramic cathode systems, that is to say those based on oxides and phosphates in known LIB systems, are poorly suited for flexible, bendable or stretchable batteries, although some embodiments have already been proposed. In principle, the inorganic-ceramic intercalation host systems are brittle and flexibility can only be achieved by using small host crystals

Admixing a flexible binder and / or conductor polymer can be achieved, but this significantly reduces the energy and power density of the battery material.

Organic and organometallic redox polymers are widely referred to in the literature as potentially active battery materials; However, their potential as active battery materials has not yet been exhausted. In particular, it has not been possible to come close to the performance characteristics of the established lithium batteries. Corresponding redox polymer electrodes and redox polymer electrochemical cells may be used as cathodes instead of lithium graphite anodes and / or inorganic ion intercalation systems.

All kinds of combinations between these two systems are possible.

However, it has not yet been possible to achieve the desired, economically interesting surface-specific charge densities (mAh / cm ² ) and area-specific maximum current (mA / cm ² ) with redox polymer materials. The reason for this is the insufficient ion and / or electron percolation behavior of the redox polymer material, a problem which could not be overcome so far.

Various approaches have already been described in the literature, inter alia in which polymeric aromatic boron and sulfur compounds or polymeric N-oxides are used. Furthermore, there are poliologists / PolitTEMPObatte- rien (TEMPO = 2,2,6 _> 6-tetramethylpiperidin-1-yl) oxyl) with PolyTEMPOschichten to 3 μιτι and linear scalable surface specific capacity up to about 120 mA cm ² , this case were at a small layer thickness of 100 nm and capacities of about 2.8 mC / cm ² (corresponding to 0.001 mAh / cm ² ) charge / discharge cycles of 60 C / cm ² possible. However, the current technique of fast charging and discharging cycles, ie those with a specific charging speed (C / cm ² )> 10, modified with redox polymer electrodes only a maximum formation of 100 Monoschich- th, so that the necessary specific capacity not be achieved.

Advantages of organic redox polymer cathodes over the conventional based on inorganic transition metals are their environmental friendliness, since the organic redox system is biodegradable, they can also be formed flexible and possible due to the corresponding synthesis freely selectable determination of the reduction potential.

Generally, during charging / discharging, electron currents flow in / out of the final current collector and ion currents flow from / into the electrolyte phase into the battery material. The local electron currents in the active layer material grow in the direction of the final current collector, while the ion currents rise in the direction of the bulk electrolyte. Ideally, the cross sections of the electron and ion current conductors in the battery material layer should be adapted to the locally expected maximum currents in order to be able to conduct currents over a large current density range without resistance at high energy density. Mazaginski (Maginski, A. et al., Nature Materials, 2010, 9 (4), 353-358) has already speculated that in the case of a lithium ion anode, efficient electron percolation through the battery material in the nanometer and micro - Until macro-scale can be met well only by a hierarchical percolation system.

Such hierarchical electron and ion conductor networks support electron and / or ion percolation at the molecular, nanoscopic, microscopic and macroscopic level. For example, micrometer-sized graphene-encapsulated Si particles are described which achieve 3.2 mA / cm ² , and SiC particles deposited on carbon black are used, which are then converted into granular structures by self-assembly. As a result, five times higher specific capacities are achieved.

In order to avoid a flow or capacity imitated situation, efficient electron as well as ion percolation must be optimized simultaneously. However, an implementation thereof for organic redox polymers is not described in the literature.

In addition to the above-mentioned problems of sufficient charge capacity, etc., environmental and safety aspects continue to play a major role. Recycling of inorganic Batte ematerialien, such as metal oxide cathodes, is complicated and even more expensive than that of lead-acid batteries. Furthermore, LIBs can heat up and burn off in the event of an internal or external short circuit, with flammable organic solvents / electrolytes playing an important role. Examples of fires in vehicles are known. Notorious is the exploding of lithium batteries with high cell voltage in case of internal short circuit. For this reason, for example, it is not possible to send small lithium batteries by means of simple air mail, it is necessary security containers.

The required cell voltages, for example, with LIBs with graphite and an L1MO2 cathode of up to 3.5 V require the use of non-aqueous electrolytes, since with water a thermodynamic decomposition voltage at 1.24 V is present. Although organic solvents / electrolytes can be used for higher cell voltage, they are often flammable. In order to overcome this problem, activation barriers have already been constructed which allow an increase in cell delivery up to 1.6V to employ aqueous electrolytes, but do not achieve the desired cell voltages of three and more volts.

The use of inorganic intercalation systems is not compatible at the molecular-nanoscopic level with a design of flexible, d. H. bendable and stretchable accumulators as they are increasingly demanded by the economy, eg. Smart watches and apparel industry. Even grinding of corresponding materials with subsequent crosslinking does not permit large area-specific current densities with a large area-specific capacity. In addition, the use of heavy metals, d. H. from Z. B. 3-D Übergangsmetal- len, as used today in LIBs (cathode material) for reasons of environmental impact of concern, and previous redox oligomer or polymer systems do not allow large area-specific current densities at large capacity.

When using an organometallic redox polymer together with graphene oxide, a molecular complex forms between the electrochemical storage medium (polyferrocene) and the nanoscale current conductor (graphene). The corresponding battery material exhibits good properties, but is> 25% heavy metal-contaminated (iron) (Beladi-Mousavi M. et al., Adv. Energy Mater. 2016, 6, 1600108; DO !: 10.1002 / aenm.201600108). Likewise, B. Gadgil et al. (Carbon 89 (2015) 53-62, DOI: 10.1016 / j.carbon.2015.03.020), it has been shown that monomeric 1, 1 '- (ethane) 1, 2-diyl) bis (4-cyanopyridine-1 -ium) in the presence of graphene oxide can be electrochemically polymerized to poly-viologen / reduced graphene oxide. However, the growth process of the poly-viologen-graphene battery material layer is self-limiting and limited to a capacity of <0.004 mAh / cm ² , so it is not suitable as a battery material.

Description of the invention

The aim of the present invention is the provision of novel electrode materials based on redox-active organic oligomers and / or polymers and graphitic material, this electrode material produced by self-assembly and subsequent activation is particularly suitable for use on nanoscopic (1-100 nm) and microscopic (0 1 to 1000 μιτι, such as 0.1 to 500 μιτι) level inventive Perkulationssysteme provide that provide improved area-specific current densities at large capacity and thickness scalability.

Surprisingly, it was found that the bad volumetric energy density hitherto assumed when using redox polymer is in fact not given by the electrode material according to the invention and the electrodes according to the invention, but rather that the materials and electrodes according to the invention show a good volumetric energy density, which is especially evident at high current densities ,

The present invention is concerned with electrochemical storage, the terms batteries, rechargeable batteries and accumulators being used interchangeably, unless otherwise stated. Accordingly, by redox-active polymers / oligomers in this invention is meant essentially electroactive substances with Nernst's and non-capacitive behavior.

By using the electrode material according to the invention with nanoscale current collector, several 100 μm thick layers can be built up on corresponding current collectors with micrometer dimensions for the formation of electrodes, in order to obtain corresponding electrodes of the next larger hierarchy. In this case, the electrode material according to an embodiment of the present invention is selected so that the potential between minus 1 volt and plus 1 volt. NHE is freely selectable. Because of the size-thickness scalability of the electrode material can be hierarchically larger power collectors effortlessly connect the electrode material. Thus, previously unachieved specific charge and current densities can be realized with organic batteries and accumulators. In addition, the electrode materials with the redox-active organic oligomer and / or polymer do not receive heavy metals, they can be operated with aqueous electrodes and / or organic electrodes and are essentially biodegradable. These redox-active organic oligomers and / or polymers (also referred to below as redox polymers) also allow the formation of flexible, ie bendable and stretchable batteries and accumulators.

In a first aspect, therefore, an electrode material in the form of a colloidal solution of a molecular complex comprising at least one maximum nanoscale redox-active organic oligomer and / or polymer and at least one nanoscale (nano-scale and nanoscopic used synonymously herein) graphitic material, which in a weight ratio of redox-active oligomer and / or polymer and graphitic material of 0.5: 1 to 20: 1 such as 1: 1 to 20: 1 and wherein the redox-like organic oligomer and / or polymer forms a complex with the graphitic material provided. In one embodiment, an addition of 1 to 10 weight percent, e.g. B. 3-7 wt.%, How 4-6 wt.%, Based on the redox polymer used, a pore-forming agent, o- of polyvinylidene fluoride, carried out in order to increase the Zyklisierbarkeit and reversibility of the material. Suitable binders or pore-forming polymers are known to the person skilled in the art.

The electrode material according to the invention can be regarded as a precursor material as long as it is not converted into an active electrode material by activation, for example reduction of graphene oxide.

This electrode material in the form of a colloidal solution permits the production of electrodes, in particular for accumulators, on corresponding current collectors, such as after in-situ activation, with the properties desired according to the invention. In this case, corresponding hierarchical structures with 2 or 3 hierarchical generations can be formed. The electrodes with the corresponding

Current collectors and the electrode material according to the invention have at least in the hierarchies a nanoscopic hierarchy (Hierarchy III), possibly a microscopic hierarchy (II) and beyond a macroscopic hierarchy (Hierarchy I). The redox-active organic oligomer and / or polymer forms a complex with the graphitic nanoscale material of hierarchy III.

Unless otherwise stated, the terms "batteries" and "accumulators" also include the other term.

In the electrode material of the colloidal solution according to the invention, the weight ratio of the redox-active oligomer and / or polymer and graphitic material is in a range from 0.5: 1 to 20: 1, such as 1: 1 to 20: 1. In one embodiment, the weight ratio is in the range of 2: 1 to 10: 1. The redox-active oligomer and / or polymer and graphitic material, both of which are nanoscale, may be one with a polycationic charge carrier of the oligomer and / or polymer and negatively charged graphene oxide.

For the complex to be electroactive polymer (or oligomer) / graphene oxide stable, the zeta potential of the colloid should be positively inverted from negative to positive upon addition of the polymer to the graphene oxide suspension. In one embodiment, the minimum weight ratio is from 2: 1 to 3: 1.

When providing an electrode material for producing batteries and accumulators with a possible optimization for high current density, the weight ratio of redox-active oligomer and / or polymer, graphitic material is preferably in a range of 3: 1 to 5: 1.

In an electrode material for producing battery material with optimized high capacity density, the weight ratio is preferably in a range of 5: 1 to 10: 1. When manufacturing the electrode material for batteries, paying attention to a high current and capacity density, the weight ratio is 3: 1 to 6: 1.

For large layer thicknesses of, for example,> 10 μιτι rather small weight ratio ranges should be used, while smaller layer thicknesses of, for example, <1 μιτι weight ratios are used in the higher ratio range.

In one embodiment, the oligomers or polymers, which are for example partially designed as dendrimers, are present in the formed complex in polycationic form. It is believed that this charge is due to either the charge of the polymer in the existing oxidation state, or by complete or partial oxidation of the polymer prior to complex formation or by synthesis in the polymer chain of the oligomer and / or polymer. In one embodiment, the colloidal solution is present in a solvent such as water or aqueous solvents.

The electrode material according to the invention has no heavy metals and / or heavy metal ions or even no transition metals and / or transition metal ions. In particular, no iron or iron ions are present in the electrode material.

The electrode material according to the invention in one embodiment has no organometallic oligomer or polymer.

In one embodiment, the oligomers and / or polymers may be present at least partially as dendrimers.

In one embodiment of the electrode material according to the invention, the redox-active organic oligomer and / or polymer has subunits with at least one, such as at least two electrophoric group of predominantly cathodic character from the classes of electrophorus from aliphatic or aromatic N-oxides, 9-alkyl and Aryl carbazoles, 1,4-di-alkyloxy and aryloxy-2,5-tert-butylbenzenes, benzoquinone diimines, N-alkyl phenothiazines or at least one such as at least two predominantly anodic electrophorus groups selected from the classes of electrophoretic groups Bipyridinium salts, quinones, anthraquinones or aromatic 1, 4 or 1, 2 dioxo compounds, aromatic tetracarboxylic acid diimides, aromatic dicarboxylic acid salts, benzylic or aromatic disulfides on.

The mentioned electrophore groups can carry a number of electronically reducible subunits, which complement each other to form a 2-electronically reducible subunit. An example is bipyridinium, which has two one-electronically reducible subunits.

The mentioned repeating electrophorus subunits are directly linked to one another or linked via a π-electron conjugated or via a non-electron conjugated bridge. It is important that as many subunits as possible participate in the charge transfer and that this takes place within the narrowest possible range of potentials.

In a further embodiment, the electrode material is one of these, which oligomers and / or polymers multiple, localized or conjugated, reverberating have oxidizable / reducible electrophores, in particular having at least two electrophore groups selected from the following groups of electrophoreses:

It was found that the electrode material according to the invention improves the formation of the hierarchies and the linking of these hierarchies with one another. The electrode material according to the invention is in particular a biodegradable electrode material.

In one embodiment, the electrode material according to the invention is one with graphene oxide and a redox-active oligomer and / or polymer based on N, N'-dimethyl-4,4'-bipyridinium.

In one embodiment, the electrode material according to the invention is a printable electrode formulation. The electrode material according to the invention may accordingly have further constituents which promote a good printability. In one embodiment, the electrode material is one that can be electrophoretically applied.

In a further aspect, the present invention is directed to a method for producing an electrode with an electrode material according to the invention. This method comprises applying the electrode material in the form of a colloidal solution to a current collector; Subsequently, the solvent in which the said components are present, while maintaining the molecular complex structure of the electrode material of the graphitic material and the redox-active organic oligomer and / or polymer on the current collector removed.

In another aspect, the electrode preparation method of the invention comprises the step of activating in which the graphitic material in the form of graphene oxide is converted by chemical reduction, in particular by electrochemical reduction, such as by reduced electrocatalytic reduction, to reduced graphene oxide.

By converting the graphene oxide into reduced graphene oxide, it is possible that this reduced graphene oxide has graphene-like properties and thus is well suited as an electrode material.

Those skilled in the art are well-known methods for reducing graphene oxide to reduced graphene oxide (rGO). Thus, this activation of the electrode material can be carried out by reduction electrochemically. This is z. For example, after applying the electrode material, the corresponding electrode is scanned several times cyclically to within the range from -1 .0 to -1.5 V as in the range of -1.1 (against Ag / AgCl) depending on the thickness of the layer , For example, as an electrocatalyst, the polymer itself is active if it is reducible more negatively than -0.5 V in the potential range, or monomeric viologen is added to the electrolyte, which then plays the role of Electrocatalyst takes over. The appropriate scan speed can be adapted to the thickness of the layer. The reduction of graphene oxide to reduced graphene oxide is indicated by a cathodic catalytic current in the range of more negative than -0.3 V, after the decrease or disappearance of the electro-catalytic current, the conversion to reduced graphene oxide is completed.

In one embodiment of the method according to the invention, the application is carried out by printing the electrode material. The person skilled in suitable methods are known. In another embodiment of the method according to the invention, the application of the electrode material to the current collector takes place electrophoretically.

In a further aspect, the present invention is directed to an electrode with an electrode material according to the invention and a current collector, this current collector is formed at least microscale.

In one embodiment, the electrode is a printed electrode or obtained by electrophoretic deposition of the electrode material on a micro or macroscopic current collector.

Herein, the term "nanoscale" means materials which are smaller than 500 nm in the smallest dimension, in particular materials smaller than 200 nm in their smallest dimension, such as smaller than 100 nm, for example smaller than 50 nm, smaller than 10 nm, the term "microscale" materials in their smallest dimension between 100 nm and 1000 μιτι, such as 500μηη, eg 100 are μιτι, and the term "macroscale" on materials that are greater than 100 μιτι in all dimensions.

The final macroscopic current collector (> 500μηη) is, for example, an electrically conductive, possibly flexible plate. The microscopic current collector is typically an embodiment consisting of carbon fibers, such as in the form of a felt or fleece or in the form of a fabric or in the form of a foam, such as in the form of a 3D carbon foam carrier material, wherein at least one dimension of the structure is in the range of 500 nm and 100 μm. or in the form of a metallic lattice with openings in the range of 10-1000 μm. The microscopic current collector can furthermore consist of an ensemble of VGCFs (vapor grown carbon fibers).

Based on the hierarchical system described herein, the current collectors are those of the hierarchy III, such as graphene oxide or conductive SW-CNTs (Single Wall Carbon Nanotubes) or MW-CNTs (Multiwall Carbon Nanotubes) or VGCNFs (vapor grown carbon nanofibers), which have positive zeta potentials after interaction with the redox polymer. The components mentioned may be partially oxidized.

Suitable current collectors of the hierarchy II are the mentioned carbon fibers in the form of felt or fleece, for example those with fibers in the thickness range of approximately 5 to 30 μm or VGCF in the thickness range of> 200 nm, or metal mesh consisting of wires with 1 -100 μm diameter and openings in the range 1 -100 μιτι.

In one embodiment, the layer thicknesses of the various components of the individual hierarchies are adjusted to be compatible with the other hierarchies. For example, the thickness of the hierarchy I layer is preferably selected to be similar to the thickness of the fiber diameter or pore diameter of the Hierarchy II current collectors, so that after receipt there is still a percolating ionic conduction system of Hierarchy II. Suitable hierarchy I current collectors are molecularly flat carbon films or plates in the thickness range of 10 μιτι to 1 cm.

The electrodes can be produced by known methods, for example, the occupation of the current collector of the hierarchy I can be done with he colloidal solution of the electrode material according to the invention such that thick homogeneous hierarchy lll / l electrodes arise. Suitable methods for coating the micro- or macroscopic current collector with the colloidal solution include:

a) Multiple (serial) application / solvent removal (as described in Example 1)

b) Continuous application of the colloidal solution by syringe on the constantly heated electricity collector

c) air brush application of the colloidal solution to the heated current collector d) electrophoretic occupation of the current collector. For use comes in the ratio of 1: 1 to 16: 1 as 3: 1 (polymer / graphene oxide, depending on the desired thickness of the battery material) prepared solution

Methods a) -d) provide similar performance but are well suited for industrial applications. In the case of a combination of all three hierarchies in the electrode, the layer thickness of the hierarchy III should also be adjusted as homogeneously as possible, but additionally in the fiber or pore size of the collector of the hierarchy II. The preparation of such an electrode with a Hierarch III electrode material and a Hierarchy II fibrous current collector can be accomplished by repetitive immersion / annealing of the fibrous electrode with the colloid.

When using graphene oxide, the production of the electrode takes place first, then the conversion of the graphene oxide into reduced graphene oxide takes place. The activation of the complex of anoxidized VGCF with the redox polymer can also lead to the improvement of the electrochemical properties.

As stated above, this includes an electrocatalytic method using self-catalysis, preferably the redox-active oligomer and / or polymer of one with E ° <-0.3 V. In another embodiment, it is an electrocatalytic method and use of a redox mediator with E ° <-0.3 V. Such a method is to be used in particular if self-catalysis is not possible. Alternatively, a non-electrocatalytic electrochemical conversion or the simple thermal method, but such a thermal method is suitable only for a few inventive redox-active oligomers and / or polymers, such as polyimides, since otherwise destruction of these can take place ,

In one embodiment, in particular one for a rechargeable battery, the electrode is designed as a flexible electrode. The current collector is selected accordingly to form a flexible electrode. In particular, this flexible electrode is one in which a carbon foil or a flexible wire grid electrode is used as a current collector and an electrode material with reduced graphene oxide or graphene as the graphitic material.

Furthermore, the present invention is directed to an electrochemical cell, in particular an accumulator, having a cathode and an anode, wherein an electrode material according to the invention and / or an electrode according to the invention forms at least one of the cathode or anode.

The electrochemical cells can be present in various combinations. This means that, on the one hand, one of the electrodes can be equipped with a device according to the invention. The electrode material should be present, while the second electrode is a conventional material or both electrodes may be made of the electrode material according to the invention.

In principle, the following combination options are available:

1 . Redox polymer anode / traditional transition metal (phosphate) cathode or

2. Traditional Li (Li-graphite) anode / redox polymer cathode or

3. Redox polymer anode / redox polymer cathode.

One embodiment thus comprises an electrochemical cell, such as an accumulator, where the cathode and the anode have an electrode material according to the invention. In a further embodiment, the electrochemical cell is a flexibly configured cell. In one embodiment, this is an electrochemical cell with an organic electrolyte, this in one embodiment, cell voltages of> 1, 5 V, such as> 2 V on.

In a further embodiment, it is an electrochemical

Cell, which has a surface specific capacity of> 20 mAh / cm ² with a total thickness of the electrochemical cell of <1 cm.

The invention is characterized in that, because of the excellent density scalability of the electrode material of the third hierarchy, the next higher hierarchies, namely the hierarchy II and the hierarchy I, can be connected to the hierarchy III in terms of capacitance and current density substantially without any loss. As a result, the electrochemical cells according to the invention, for example based on the redox-active organic oligomers and / or polymers, achieve performance values which have hitherto only been achieved by heavy metals containing LIBs. The electrode material according to the present invention is scalable in the range of 100 nm to 2 mm.

In a suitable embodiment, these are electrodes and electrochemical cells having such electrodes, wherein the current collector is one of the next larger hierarchy II, for example a three-dimensional current collector based on a foam or based on a carbon fiber fleece. Suitable fibers are, for example, the 1 D graphite fibers of a carbon felt, the fibers of a carbon nonwoven consist of fibers in the thickness range of about 5 to 20 μιτι or VGCFs with diameter of> 500 nm. In dense fibers or spaced fibers, the intermediate regions with the electrode material according to the invention An optimal solvent and electrode percolating system of two hierarchical generations is created. This will be further explained below. This allows surface-specific capacities of 21 mA / cm ^{2 to be} achieved. In addition, the electrochemical cells are those that are compostable, that is, have the biodegradable materials.

The electrochemical cells according to the invention are particularly suitable as batteries / accumulators in the mobile sector. Another particularly suitable application is the use as flexible electrochemical cells, for example in the field of clothing or smartwatches, etc.

The electrochemical cells may also have aqueous electrolytes, this represents in particular environmentally friendly batteries.

Finally, the present invention provides a process for preparing a viologen-group-containing oligomer or polymer. This procedure includes the steps

- Providing a 1, 1 - (2,4-dinitrophenyl) -4,4-Bipyridiniumdichlorids and a second unit comprising at least two amino groups;

- Reacting these two compounds to release a 2,4-dinitroaniline to give an oligomeric or polymeric viologen-containing compound.

In one embodiment, the reaction takes place after a Zincke reaction.

The invention will now be further explained with reference to the figures and to the examples.

The invention relates to the production and use of a hierarchical conductor system with 2 or 3 hierarchical generations, for organic, electroactive, oligomeric or polymeric, rigid or flexible battery materials, wherein the hierarchies necessarily the nanoscopic (Hierarchy III), possibly the microscopic (II) and necessarily include the macroscopic area (hierarchy I) (Figure 1 and 2). The conductor material preferably consists of graphene oxide / graphene but can also consist of conductive CNTs (carbon nanotubes), multiwall CNTs, or VGCNFs (vapor grown carbon nanofibers). The hierarchical electron conduction system is paired with a nanoscopic, preferably likewise hierarchically structured, ionic conductor system. For the production of nanoscale Generation III grain Positively the molecular self-assembly of oligomeric, dendritic or polymeric organic or organometallic, in particular multi-cationic, redox-active compounds or salts is used on the nanoscopic conductive or latently conducting, nanoscale, advantageously negatively charged current collectors. This technique makes it possible for the first time to produce anodic or cathodic redox polymer battery composites of hierarchy III with thicknesses down to sub-μηη down to the mm range, without any great sacrifices in terms of area-specific capacitance and current density. Thus, the composite surpasses corresponding redox polymers without the nanoscopic nanoscopic conductor system by a factor of 10 to 1000 in terms of current density and capacitance.

Hierarchy III, self-assembly:

The production of the hierarchy III nanoscopic current conductor / ion conductor / redox polymer system is based on the self-assembly of oligomeric, dendritic or polymeric organic or organometallic, in particular multi-cationic compounds or salts (the polycationic reversible charge carriers) on nanoscopic conductive or latent conductive , preferably multiply negatively charged, graphitic materials such as graphene oxide, partially oxidized conductive carbon nanotubes or carbon fibers (VGCNFs). In principle, it is possible to use all known oligomeric or polymerizable organic or organometallic, reversible redox systems as charge carrier components. Particularly suitable are polycationic charge carriers that undergo electrostatically driven self-assembly with the nanoscale current collector systems. The preparation of the polycationic charge carriers is described in Figure 5. In principle, systems with the redox-active component (RA) in side chains (MX) or in the main chain (IX) are suitable. The positive charge either occurs naturally in the stable state, or must be caused by partial oxidation of the charge carrier prior to self-assembly, or it must be synthetically introduced by linking to a persistent positive group (PC ⁺ ). In certain cases (in extended π systems, eg, in aromatic polyimides), the π interaction already suffices to form the self-assembly of reversible charge carriers and nanoscopic current collectors. In this case, preferably, a phase transfer reaction between aqueous-colloidal solution of graphene oxide and a homogeneous solution of the uncharged redox polymer, for example in diethyl ether, as described in Example 5, for use. Possible structures concerning the redox-active unit (RA) are shown in Table 1. The table shows monomeric classes and each a typical molecular representative. The integration of molecular RA into a polymer is not documented in the table, but is well known to the skilled chemist in the literature. In Examples 1-5, the synthesis of the oligomers and polymers is presented in detail.

Possible combinations of redox systems (Hierarchy III)

All of the monomers shown above are redox systems, the more stable oxidation state being indicated. Depending on the substituents, they are water- and / or organic-soluble and are characterized by a localized electrophore group, which is accompanied by a limited extent of HOMO and LUMO. Polymerization generally does not alter the expansion of the electrophor and, in particular, does not necessarily produce electronic conductivity in the polymerization such as in the case of polythiophene or polyaniline. Electron transfer within a polymer chain therefore takes place via an "electron hoping mechanism", as long as it is not in molecular contact with the nanoscopic conductor. An important aspect of this invention is that the slow "electron hoping mechanisme" between the redox systems in the polymer can be achieved by a rapid electron flow in the nanoscopic ladder (after polymer self-assembly on graphene oxide and its reduction to graphene). This fact explains why above all a Faraday and no capacitive current is observed. The redox units in Table 1 are roughly divided into anodic and cathodic. Since most composite materials are to be used in organic as well as in aqueous systems, a precise specification of the standard reduction potentials is not possible. However, the potential difference between the compound with the most positive (1, 4-di-t-butyl-2,5-dimethoxybenzene) and the most negative potential (dihydrotetrathia-anthracene) is> 2.3 V. Compared to a lithium electrode, all redox systems are of course cathodic (Range approx. +3.5 to +1.5V).

The self-assembling surface modification can be carried out on graphene oxide, on oxidized CNTs or on oxidized VGCNFs. As already mentioned, the negatively charged graphene oxide is particularly suitable as a precursor to a nanoscale current collector because the self-assembly of the polycationic redox polymers on suspended graphene oxide layers is particularly efficient. to Self-assembly is slowly added to a solution of about 0.1-5 mg / ml of the polymer, preferably in water and under the action of ultrasound, a solution of graphene oxide (1 -4 mg / ml, also in water). The final mass ratio polymer / graphene oxide can be chosen from 2 to 10 (stable colloidal solution). In order to favor high current densities the ratio polymer / graphene oxide should be small. To reach high capacities it should be as high as possible. Each battery application can thus be optimized individually. The formation of the complex can be monitored by changing the zeta potential of the colloid. The strongly positive values indicate a double-sided coating and sometimes multiple wrapping of the graphene oxide particles (see Figure 3). At a polymer / graphene oxide ratio> 10: 1, the efficient electron percolation threshold can be undercut.

Another feature of the present invention is the extremely large calorificability of the Generation III composite without significant loss of observed capacitance even at high current densities. The previously known redox polymer electrodes exhibited corresponding growth of the observed capacitance at high current densities up to a maximum of about 100 nm layer thickness. No other known additive (carbon black, electrically conductive polymers, etc.) has so far shown a similar performance increase in the electrochemical behavior of oligo or polymeric organic battery materials. In addition, it is shown with Examples 1-4 that the invention presented here has general validity and applies to a wide variety of redox oligomers and polymers.

Flexible anodes, cathodes and complete batteries and accumulators:

The composite of the hierarchy III is in its thickness of 0.1 to 1000 μιτι scalable over a considerable current density range without loss of capacity. Mostly made of a non-crystalline polymer, it is also flexible. As shown in Example 1, the composite can be on a bendable, 0.2 mm thick

SIGRACET TF6 (SGL Carbon). The resulting battery type of the hierarchy type III / 1 is therefore also bendable. At capacitances of 0.6 to 1 .2 mAh / cm ² under load up to 16 mA / cm ² hardly measurable capacity loss is found (Example 1, electrode b)). In addition, the lll / l electrode shows no capacity losses after 200 bending cycles (radius 1 .8 cm). Instead of the flexible graphite electrode (Hierarchy I), a flexible titanium wire mesh electrode (Hierarchy II l) can be used as a current collector, wherein the assignment of the titanium wire Elekt- can take place with composite electrophoretically. Since both anodic and cathodic redox polymers have the described thickness-scalable properties described in this patent, it is obvious that the expert is able to assemble a complete, flexible battery therefrom. It is therefore an important aspect of this invention that the use of Hierarchy III's composite on hierarchical I flexible current collector can result in thin flexible batteries. Thus, this invention represents a solution to the general problem concerning the production of flexible batteries for a variety of mobile applications.

Polymer redox batteries and accumulators with extremely high surface-specific capacities and high current densities. For polymer redox batteries, large capacitors could not be produced at high current density. Due to the great thickness scalability of the hierarchy III composite, it is now possible, starting from the Hierarchy III composite, to connect the next higher hierarchy II of electricity and ion flux collectors to the hierarchy III without loss (Example 1. Electrode c with hierarchy l / ll / III reaches 21 mAh / cm ² ). For the first time, batteries based on organic (or organometallic) redox-active oligo- or polymers achieve performance levels that have so far only been achieved by commercial, but heavy-metal-bonded LIBs. The practical implementation of Hierarchy II - Hierarchy III connectivity is shown in Figure 4. Since the composite material (Hierarchy III) is scalable in the range of 100 nm to 2 mm, the current collector of the next larger hierarchy II must have an extent (in one dimension) of 100 nm to 2 mm. Suitable are, for example. The 1d graphite fibers of a carbon felt, the fibers of a carbon flow consisting of fibers in the thickness range of about 5-30 μιτι, or thick (diameter> 500 nm) VGCFs (see Fig. 4-4). If the individual fibers are dense (or even better with a spacing also in the 5-30 μιτι (or about 1 μιτι for VGCF) area occupied, so there is an optimal solvent and electron-percolating system of 2 hierarchy generations ( including concluding flat collector plate: with 3 hierarchies) Example 1 shows that this easily achieves a surface-specific capacity of 21 mAh / cm ² (with a non-optimized layer thickness of about 2 mm) Carbon foam as a stream of collector material of the hierarchy generation II (see Fig. 4.5). It is an important aspect of this invention that by using the thickness scalable composite hierarchy generation III and using a 3d current collector of the hierarchy generation II with adapted current conductor dimensions in the μιτι area for the first time redox polymer batteries with similar good properties are produced as they are the traditional known Have batteries and accumulators. However, the redox polymer batteries are generally more environmentally friendly ("compostable" materials, not heavy metals, and with the option of using an aqueous electrolyte). pictures:

Figure 1: Electrode material with hierarchy generations I and III:

a) Electron conductor: la: Generation I electron conductor: macroscopic current collector (typically graphite plate) in electrical contact with: purple: Generation III electron conductor: nanoscopic current collector (typically reduced graphene oxide) in molecular self-assembly contact with redox polymer c).

b) ionic conductor: Ib: Generation I ionic conductor: micro- or macroscopic ions bulk (typically aqueous or organic electrolyte, possibly polymeric or gel-like) in ionic contact with: IIIb: Generation III ionic conductor: nanoscopic self-assembled tube system (typically redox polymer + graphene oxide / reduced graphene oxide).

c) redox oligo- or polymer or dendrimer.

Figure 2: Electrode material with hierarchy generations I, II and III

a) Electron conductor: la: Generation I electron conductor in electrical contact with: IIa: Generation II electron conductor: microscopic current collector (typically graphite fibers) in electrical contact with: purple: Generation III electron conductor in contact with redox polymer c).

b) ion conductor: Ib: Generation I ionic conductor in ionic contact with: IIb: Generation II ionic conductor: microscopic electrolyte channel (typically macropores in graphite felt or flow in ionic contact with IIIb: Generation III ionic conductor in contact with c)

c) redox oligo- or polymer or dendrimer.

Abbreviations as in Fig. 1 Figure 3: Colloidal ladder / polymer carrier suspension, precursor of Generation III battery material

Colloid particles in aqueous solution consisting of nanoscopic electron conductor with negative surface charge (black) surrounded by 2d and 1 d nanoscopic polymeric redox charge carriers (vertically hatched). Total surface charge of the colloid: positive. Removal of solvent produces battery material (charge carriers / electrical conductors / ion conductors of the hierarchical generation III (Figures 1 and 2).

K1: neg. Charged 2dim graphene oxide (2, with 2 nm <d2 <50) enveloped by pos. charged redox polymer / oligomer / dendrimer (1)

K2: pos. charged 1dim CNT (with 2 nm <d2 <50) or VGCNF (3, with d2 <500 nm) enclosed by the pos. charged redox polymer / oligomer / dendrimer (1) Positive total charge adjusted by ratio of 1: 2 or 1: 3 in the range 2: 8 (g / g)

d1: Thickness of 1 on conductor (0.5 <d1 <5 nm).

Figure 4: Hierarchy III and combinations Hierarchy III / II

4-1 and 4-2: Generation III electrode material

(nanoscale with bulk dimensions) consisting of a mixture of nanoscale composite material with additionally formed mesopores, formed by partial deprivation of solvent from K1 (2-dimensional nanotubes) or K2 (1-dimensional graphene oxide / graphene) (see Fig. 3).

1 a: oligomeric or polymeric reversible redox compound as polymer matrix in contact with 2a and 4a

2a: Electron percolating conductor system consisting of 1-din nanoscale conductor (for example CNT, multiwall CNT) with 0 nm <d4 <50 nm

3a: Electron percolating conductor system consisting of 2-diminus nanoscale conductors (for example graphene oxide / graphene) with 30 nm <d4 <50 nm

4: Ion-percolating mesoporous ladder system, formed by self-assembly of the polymer and by interaction of the colloid during solvent removal

d3: depth of the nanoscale composite material, (100 nm <d3 <500 μιτι)

4-3: Abbreviation for 4-1 and 4-2 (composite material in a thickness of 100nm <d3 <

500 μιτι) used in in 4-4 and 4-5. 4-4 and 4-5: macroporous, electron and electrolyte ions percolating carrier material with composite material 4-3.

4-4: Electron and Lonenperkolationssystem the 2nd hierarchical generation using 1 -d graphitic fibers in the form of graphite felt, Graphitfließ, or thick VGCF) with an I d-conductor diameter of 500 nm <d5 <20 μιτι, an original porosity of 50-95%, and a thickness d4 of Ι ΟΟμιτι <d4 <10 mm. 4-5: Electron and electrolyte percolating carrier material consisting of carbon foam with a pore density of 10 - 200 ppi.

5: 1 d current collector consisting of a plurality of graphitized carbon fibers with an I d conductor diameter of 500 nm <d5 <20 μιτι and 1 d length (L, 10μηη <L <10 cm). The fibers per se form an electron-percolating conductor system (touch points)

6: Percolating, macroporous electrolyte conduit system with a pore diameter of 50 nm <d6 <100 μιτι. The pore system exists naturally and is reduced by the occupancy of the inner surface, but not prevented.

7. carbon foam pore with pore diameter d8 (200 μιτι> d7> 10 μιτι)

8. Carbon foam pore wall mt thickness 10nm <d5 <1 μιτι

Figure 5: Principally permissible polymer types with cationic total charge for self-assembly on graphene oxide

Illustration Principles for the formation of polycationic redox polymer electron memories.

MX: polymers, oligomers and dendrimers with redox center (RA) in the side chain in the

polycationic state (prepared for self-assembly on graphene oxide).

IX: Polymers, Oligomers and Dendrimers with Redox Center (RA) in the Main Chain in the

polycationic state (prepared for self-assembly on graphene oxide).

X: Polymers, oligomers and dendrimers with redox center (RA) in the side or the main chain in the neutral state, convertible by partial oxidation in the state MX or IX.

R: non-redox active chain subunit

RA: electroactive side-chain subunit

RA ^* : electroactive backbone subunit PC +: persistently positively charged subunit

n: Number of subunits in the polymer, oligomer or dendrimer

m +: number of persistent charges generated by (partial) oxidation of RA or

RA ^* ,

where m ⁺ <= n

example 1

Synthesis of Redox Polymer Poly (vinyl-diphenyl-4,4'-bipyridinium) dichloride (poly-1): 4.5 g (8 mmol) bis- [1,1 '- (2,4-dinitrophenyl-4,4'-bipyridinium Dichloride)],): (1) and 1 .7 g (8 mmol) of 4,4'-ethylenedianiline were dissolved in a mixture of methanol / water (8: 2 (v: v)) and reflux / Ar atmosphere polycondensed for 14 days by Zincke reaction. The solvent was removed and the residue was refluxed in acetone for 6 h, filtered and the filter cake was washed with acetone and dried under high vacuum, yield: 3.19 g, 7.84 mmol), 98% poly (vinyl-diphenyl-4,4 '-bipyridinium), 12 «n <7. (1).

Preparation of the colloidal solution. Variant 1: 3 g (7.36 mmol) of 1 was dissolved in 750 ml of F O / methanol (9: 1 (v: v)). 250 ml of an aqueous solution of graphene oxide (4 mg / ml, Graphenea SA, San Sebastián, Spain, with C: 49-56%, O: 41-50%, H, N, S each 0) was added to this solution under the action of ultrasound -2%) over 30 minutes. In a second variant, a polyvinylidene (PVDF) may additionally be added to the colloidal solution of variant 1 as a pore former, for. In an amount of 5% by weight based on the amount of redox polymer.

Preparation of the modified electrodes:

a) Hierarchy Type III / L on Rigid Current Collector:

a1) A glassy carbon electrode (Metrohm, Herisau, CH 0.07 cm ² ), or a2) a 0.7 mm thick graphite electrode (SGL GROUP, SIGRACELL PV15 graphite plate, Wiesbaden DL) with the dimensions: and weight: 1 ^* 1 cm ² : 130 mg b) Hierarchy type lll / l on flexible current collector: a flexible graphite foil

(SGL GROUP, SIGRACET bipolar plate TF6: 0.2 mm thick). Current collector weight: 1 ^* 1 cm ² : 24mg. c) Hierarchy type III / II / L on a rigid current collector: a carbon felt electrode (SGL GROUP, SIGRACELL GFD3 BATTERY FELT - R & D grade surface treated) with macroscopic dimensions of surface and 3 mm thickness was used. Dimensions: Weight : 1 ^* 1 cm ² : 21 mg. The felt electrode was pressed against a SIGRACELL PV15 (graphite plate).

To the electrode a1), the colloidal solution was applied stepwise with a syringe, then heated in the oven at 50 ° C for 15 min and it was the next application of the colloidal solution. The sequence of colloid solution application / heating was repeated until the value indicated in the table was reached (applied dimensions).

Surface modification:

The electrodes a2) and b) were heated on a hot plate at 100 ° C. during the colloidal solution application. The amounts applied in the example led to layer thicknesses of 45 and 400 μιτι composite on the flat current collector (the corresponding specific die electrode c) was similar to that described for a1) gradually treated with colloid solution, slightly pressed and heated in the oven to the weight ratio Komposi carbon felt 10 mg / mg.

Conversion of graphene oxide into reduced graphene oxide and electrochemical properties of the resulting modified electrodes:

The electrodes a) -c) described above were switched as a working electrode in a 3-electrode system (reference electrode: Ag / AgCl / KCl, auxiliary electrode: Pt wire, electrolyte: 0.1 M KCl). The potential of the working electrode was scanned several times over the range (0-1 .3-0 V etc, for thick layers: potential range to -1.5 V) depending on the thickness of the composite layer at 0.1 to 0.001 V / s until the Catalytic flow in the range -0.6 to -1.3 had completely disappeared.

The capacity of the resulting modified electrodes prepared according to Variant 1 were measured in aqueous 0.1 M KCl electrolyte,

Electrochemical measurements on polyimide (compound 1)

Amperometry ^x cycle. Voltammetry * Electrodes - Appl. spec. Dimensions / Appl. spec. Dimensions / Appl. spec. Dimensions /

Electrolyte / LöAufbau appl. spec. Capacity / appl. spec. Kapaziappl. spec. Capacitor monitored. spec. Capacity / ob. spec. Katät / beob. spec. Ka / appl. Stoma density in capacity / appl. capacity / scan rate

Stoma density in

(mg / cm ² ) / (mAh / cm ² ) (mg / cm ² ) /

/ mAh / cm ² ) / (mA / cm ² ) (mg / cm ² ) / (mAh / cm ² ) /

mAh / cm ² ) (mAh / cm ² ) / (V / s)

/ (mAh / cm ² ) / (mA / cm ²

) a1) ^v > 0.07 / 0.008 / 0.007 / 0.18 / 0.02 / 0.018 / 6.1 /0.7/0.69/0.005 0.1 M KCI / H2O

94 94

al) w) - - 5.1 /0.6/0.21 /0.005 0.1 M KCI / H2O a2) 51 / 5.8 / 5.7 / 8 51 / 5.8 / 5/16 115 / 13.7 / 13.3 / 0.1 M KCI / H2O

0.0002 b) before Bie5.2 / 0.59 / 0.59 / 8 10.9 / 1.23 / 1.16 / - 0.1 M KCI / H2O tested ^y) 16

b) according to Bie5.2 / 0.59 / 0.59 / 8 10.9 / 1.23 / 1.14 / - 0.1 M KCl / H2O tested ^y) 16

Cyclic voltammetry * Amperometry ^x c) 195/22/21 / 0.001 88.5 / 10/10 / 0.001 - 0.1 M KCl / H2O a1) Polymer 2.1 /0.28/0.07/ 0.1 M KCl / H2O without Gra- 0.001

phene

z>: Redox polymer Compound 1 accounts for 85% of the total weight (15% is Gaphen)

^*) : Values from CV Measurement: last entry Scan Rate in (V / s)

x ⁾ ; Values from amperometry: final indication of imposed stoma density in (mA / cm ² ) y): The composite-modified electrode strip (0.2 mm thick SIGRACET TF6) of 5.6 cm length was compressed 200 times in 20 s each into a semicircle with radius 2.8 cm and stretched back to full length.

v>: polymer / graphene oxide ratio: 3/1

w>: polymer / graphene oxide ratio: 8/1

The redox polymer compound 1 accounts for 85% of the total weight (15% is Gaphen). Taking into account the graphene fraction results in a specific one Capacity of 137 mAh / g r. With hierarchy type lll / l (a2, thickness of the battery material: 460 μιτι) 13.3 mAh / cm ^{2 are} measured. This results in a volumetric, area-specific charge density of 289 mAh / cm ³ , with> 97% coulometric efficiency being achieved.

Colloidal solutions, prepared according to variant 2, provide a further increased

Stability and better reversibility.

Using the combination of hierarchy type III / II / I (c), at least 21 mAh / cm ^{2 can be achieved} at> 95% coulometric efficiency. Due to the additional use of the microscopic current collector (carbon felt), the specific capacity drops from 137 mAh / g to 15 mAh / g. On the other hand, however, higher area-specific capacities can be achieved. The capacity loss after 100 charge / discharge cycles in H2O / KCI is <5%.

Example 2

Synthesis of the tri-viologen-tetra-bisanisidine redox oligomer (2):

The precursor V2i * 2CI "was prepared according to literature Nanasawa, M. et al., The Journal of Organic Chemistry 2000, 65 (2), 593-595.

For the preparation of V22 * 2 Cl ^" 2g (3.56 mmol) V2i ^* 2 Cl ^" in 250 ml of MeOH / hbO (8: 2 (V: V)) was dissolved at 50 ° C, and with 2.2 g (9.05 mmol) -Dianisidine in 200 ml in MeOH / h O (8: 2 (V: V)). The mixture was refluxed for 20 h, the solvents evaporated, and the residue washed with acetone. After drying, V22 * 2 Cl ^" (1.98 g, 82%) was obtained, and 0.5 g (0.73 mmol) of V22 * 2 Cl ^" and 1.7 g (3.02 mmol) were used to prepare the hexafluorophosphate salt of V23.

V2i * 2CI ^" in 250 ml MeOH / h O (8: 2 (V: V)) for 72 h The solvent was distilled off and the crude product was precipitated twice from methanol / ethyl acetate The yellow product was taken up in 200 ml of methanol and added to 10 ml of a 3 M aq. NH ₄ PF 6 solution. The filtrate was then precipitated from MeCN / Diet- hylether. After drying under HV was V23 * 6 PF6 as a dark yellow product was obtained (1 .32 g, 86%). For the preparation of 2 ^* 6 PFe, 0.9 g (0.42 mmol) of V23 * 6PFe ^" and 0.55 g (2.25 mmol) of o-anisidine were refluxed in 100 nl MeCN for 48 h. The crude product was precipitated from the solution by addition of 250 ml of diethyl ether at room temperature, filtered, washed several times with MeOH and then with diethyl ether. The product was then repeatedly dissolved in MeCN and precipitated with diethyl ether, and finally dried in a HV: 2 ^* 6 PFe ^'was obtained as a dark-colored material (0.89 g, 93.4%).

¹ H NMR (CDCN, 250 MHz) δ: 9.19 (bs, Vio, 12H); 8.69 (bs, vio, 12h); 7.83 (s,

Charom. , 4H); 7.74 (bs, CHarom., 10H); 7.56 (bS, CHarom., 4H); 7.27 (bS, CHarom., 4H);

6.87 (bs, CHarom., 2H); 4.45 (s, NH ₂ , 4H); 4.1 1 (s, O-CHs, 12H); 4.05 (s, O-CHs, 6H); 4.00 (s, O-CHs, 6H).

Preparation of the colloidal solution: 0.3 mg of multi-wall carbon nanotubes (MWCNT-COOH (8%)) with a degree of carboxylation> 8%, an average diameter of 9.5 nm and an average length of 1 .5 μητι, Aldrich, No. 755125 ) were suspended in 6 ml of DMF by short-time ultrasonic treatment at 0 ° C. 1 .5 mg of the oligomer 2 was dissolved in 20 ml of DMF, added slowly to the MWCNT-COOH dispersion and further sonicated for 30 minutes.

Preparation of the Modified Electrodes: Electrodes of the type a1) (hierarchical type III / 1 on rigid, glassy carbon) were produced as described in Example 1. The construction of the modification layer was likewise carried out as described for a1) systems in Example 1. Electrochemical properties of the resulting modified electrode

Only thin-layer modified electrodes were investigated. The thickness scalability was not investigated in detail.

The redox oligomer 2 corresponds to 83% by weight of the composite (17% is MWCNT-COOH). Specific capacities> = 0.1 mAh / cm ² . Coulomb efficiencies> 95% at 101 mAh / g are observed in both aqueous and organic electrolytes with hierarchy combinations III / L. The capacity loss is <5% over 30 CV charge / discharge cycles in MeCN / LiCIO4.

Comparative Example 1

Synthesis of Partially Oxidized Poly (vinylferrocene (PVFc).) PVFc (3) is commercially available (Polysciences Inc., Warrington, PA) The polymer of n = 50 partially became to PVFc ^{z +} in a 2-phase solvent system as described ^■ ZNO3 ^" (10 <z <30%) is oxidized (Beladi-Mousavi et al., Adv., Energy, Mater., 2016, 6, 1600108, DOI: 10.1002 / aenm.201600108).

Preparation of the Colloidal Solution: An aqueous graphene oxide dispersion (0.29 g in 580 ml, specifications, see Example 1) was added dropwise to a PVFc ^{z +} .zNO 3 ^" (3) suspension (1 .27 I, 6 mmol = 1 The solution was diluted with distilled water (0.68 l) and sonicated for a further 30 min.

Preparation of Modified Electrodes: Electrodes of type a1) (hierarchical type III / 1 on rigid glassy carbon) were prepared as described in Ex. The structure of the modification layer was likewise carried out as described for a1) systems in Example 1).

The reduction of the graphene oxide in the composite material of the modified electrode was carried out electrocatalytically in a solution of 0.1 M L1CIO4 / 4 * 10 ^-3 M methyl viologen. The potential of the working electrode (details as in Ex. 1) was scanned until the catalytic stream had disappeared. After the electrochemical reduction, the modified electrode was heated at 50 ° C. for 30 minutes in dist. Washed water.

The properties of the poly-3 composite electrode in aqueous and organic electrolytes, as well as in comparison to the electrode material without graphene are summarized in the table:

Electrochemical measurements on poly (vinylferrocene) (Compound

3) Amperometry ^x cycle. voltammetry

_**

Electrode type appl. spec. Dimensions / appl. spec. Dimensions / appl. spec. Dimensions / electrolyte / Löappl. spec. Capacity / appl. spec. Kapaziappl. spec. Capacitor monitored. spec. Capacity / ob. spec. Katät / beob. spec. Ka / appl. Stoma density in capacity / appl. capacity / scan rate

Stoma density in

(mg / cm ² ) / (mAh / cm ² ) (mg / cm ² ) /

/ mAh / cm ² ) / (mA / cm ² ) (mg / cm ² ) / (mAh / cm ² ) /

(mAh / cm ² ) / (mAh / cm ² ) / (V / s)

mAh / cm ² ) / (mA / cm ² )

a1 0.014 / 0.0015 / 0.024 / 0.0025 / 2 / 0.21 / 0.21 / 0.01 0.1 M UCI04

0.0014 / 7 0.0023 / 5.4 / CH3CN a1 2 / 0.21 / 0.21 / 0.01 0.1 M L1CIO4 /

a1 0.43 / 0.054 / 0.01 / 0.1 M L1CIO4 /

Pure Re-0.01 CH3CN doxpolyme

without graph

The composite material consists of 88% of the redox polymer (12 percent by weight is deposited on the graphene). The composite allows specific capacities> 0.21 mAh / cm2 at 29 μm layer thickness and> 99% Coulomb efficiency (capacity density of the material (including graphene) = 1 14 mAh / g). The capacity loss after 300 charge / discharge cycles is <5% ,

Example 4

Synthesis: 1,1,5,8-Naphthalenetetracarboxylic dianhydrides (NTCDA, 0.536 g, 2 mmol) and 2,3,5,6-tetramethyl-1,4-diaminobenzene (0.32 g, 2 mmol) were dissolved in dimethylacetamide (DMA ) and brought to 140 ° C for 3 days for polycondensation. The precipitated product was isolated by filtration, washed with ethanol and water, and dried under high vacuum at 50 ° C (0.25, 0.64 mmol (32%), n could not be determined.

Preparation of the colloidal solution: 0.3 g (0.75 mmol) of 4 was dissolved in 100 ml of DMF and admixed with ultrasound with 15 ml of a graphene oxide suspension (4 mg / ml). After addition, the suspension was sonicated for a further 30 min. Electrode modification: 0.29 ml of the composite suspension was added dropwise to an FTO glass electrode (Fluorine doped tin oxide, 10 Ω / sq, 1 ^* 1 cm ² dimensions) (using the drop-casting heating method described in Example 1) ).

The activation was carried out either electrochemically (as described in Example 1) or thermally. The electrochemical activation was carried out by self-catalytic reduction without additional viologen, in principle as shown in Example 1, wherein 0.5 M TEABF ₄ in ChbCN was used as the electrolyte, the scanning range from 0 to -2.5 V and a scanning speed of 0.005 to 0.05 V / s was created. In the alternative method, the reduction of graphene oxide was thermally effected by heating the FTO glass plate to 400 ° C for 2 hours.

Electrochemical properties with thermal and electrochemical reduction, as well as with the use of organic electrolyte / solvent are listed in the table:

Cyclic voltammetric investigations on polyimide composite 4 on FTO electrodes

Comparison of electrochemical and thermal transformation of graphene oxide in

graphs

All electrodes beappl. spec. Dimensions / appl. spec. Dimensions electrolyte / loosened from FTO appl. spec. Capacity / / appl. spec. medium on glass. spec. Capacity / capacity / beob.

The reduction of the scan rate (mg / cm ² ) / spec. Capacity /

followed by electrochemistry (mg / cm ² ) / (mAh / cm ² ) / scan rate

mixed or ther (mAh / cm ² ) / (V / s)

mixed. (mg / cm ² ) /

(mAh / cm ² ) /

(mAh / cm ² ) / (V / s)

Electroreduction 0.36 / 0.044 / 0.044 / 0.89 / 0.1 1 / 0.5M TEABF ₄ / a1 (FTO) ^* , 0.01 0.089 / 0.01 CHsCN

Therm. Reduction 0.36 / 0.044 / 0.044 / 0.89 / 0.1 1 / 0.5M TE-a1 (FTO) ^* 0.01 0.093 / 0.01 ABF / CHsCN a1 (FTO) 0.22 / 0.03 / 0.001 / 0.5M TE-pure polymer 0.01 ABF / CHsCN

* T = 130 ° C, 20 min

The thermal and electrochemical methods lead to identical results. The thermal method can only be applied to a few polymers. The redox material 4 accounts for> 90% of the total weight. Specific capacities> 0.1 1 mAh / cm ² are possible, both reduction methods provide Coulomb efficiencies> 80%, capacity losses after 30 CV charge / discharge cycles were <5%.

Example 5

Synthesis of poly-o-dianisidine-NTCDA (4a)

4a

Synthesis: 488.00 mg (2.0 mmol) of o-dianisidine in 15 ml of dimethylacetamide (DMA) and 538.00 mg (2.0 mmol) of 1, 4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA) in 20 ml DMA each at 40 ° C for 20 minutes and dissolved with stirring. The solutions were combined and the polycondensation was carried out at 140 ° C for three days under reflux. The red-brown precipitate was cooled to RT and separated with a glass frit and washed with 20 ml of water and then dried at 40 ° C under high vacuum (yield: 580 mg, 61%). About 30 mg of this amount was dried for one day at 180 ° C and then passed to the spectroscopic analysis.

1 H-NMR (DMSO, 250 MHz): 8.818-8.620 (s, 4H); 7.561 (m, 6H); 3.905 (s, 6H) Preparation of colloidal solution:

30 mg of poly-o-dianisidine-NTCDA (4a) was dispersed in 15 ml of diethyl ether under the action of ultrasound for 30 minutes. The dispersion was added to 1 mg of graphene oxide in 5 ml of water. The two-phase system was stirred mechanically for 24 h. An emulsion formed. After separation of the two liquid phases, the molecular complex poly-o-dianisidine-NTCDA @ GO was in the aqueous phase.

EXAMPLE 6 Production of a Stable Colloidal Solution of Poly (vinyldiphenyl-4,4'-bipyridinium) Dichloride Poly-1 as in Ex. 1 and Graphene Oxide with Increased Mass Concentration (22 mg / ml) and Viscosity:

To 1 ml of the commercial solution of graphene oxide (4 mg / ml water, manufacturer: Graphena Germany) was added 1 ml of a solution of 40 mg poly-1 in 1 ml methanol. The mixture was mixed at room temperature for about 5 minutes by ultrasound or> 10 minutes with mechanical stirring. The result was a stable, colloidal, slightly viscous solution (weight ratio of polymer / graphene oxide = 10: 1, concentration of the complex 22 mg / ml). The colloidal composite solutions were applied to carbon plates by spraying. For this purpose, about 2 ml of the colloidal solution were placed in the reservoir of an "air break" spray gun and the colloid was sprayed from about 5 cm by air pressure through a 0.2 mm nozzle and applied to the current collector during the spraying process held at about 60 ° C by a hot plate so that the solvent was allowed to evaporate sufficiently during spraying (4-10 minutes) to allow continuous spraying.The amount of sprayed poly-1 / GO complex was determined by weighing the electrode after annealing (1 h at 150 ° C.) The transformation of GO into rGO was carried out as described in Example 1. The electrochemical results are given in the table below.

Composite battery material (poly-1 / rGO) applied to carbon plates by spray method, cyclic voltammetric measurements Electrode - applied dimensions (mg / cm ² ) / auf¬

Electrolyte / solvent

Construction area capacity (mAh / cm ² ) /

Obs. Area capacity (mAh / cm ² ) /

Obs. volumetric capacity

(mAh / cm ³ ) /

Scan rate (V / s) a1 1 1.95 /1.5/1.48 / 9 /0.0005 0.5 M KCI / H2O

a2 3.98 / 0.5 /0.5 / 9 /0.005 0.5 M KCI / H2O

b1 4.4 / 0.5 /0.49 / 9 /0.002 0.5 M TEABF4 / ACN

b2 4.4 / 0.5 /0.48 / 9 /0.002 0.5 M LiPFe / PC

Poly-1 / GO ratio: 10/1, electrolyte: aqueous

Poly-1 / GO ratio: 3/1, electrolyte: organic. PC: propylene carbonate, ACN: acetonitrile, TEABF4: tetraethylammonium hexafluorophosphate

Example 7: Preparation of stable colloidal pastes of polymer 1 and graphene oxide with maximum mass concentration (75-750 mg / ml):

720 mg of poly-1 was dissolved in 18 ml of methanol. This solution was added to 10 ml graphene oxide (4 mg / ml water, manufacturer: Graphena) and sonicated for 10 minutes (or alternatively stirred vigorously for 1 hour). The resulting colloidal solution (27 mg complex / ml) was concentrated on a rotary evaporator to a volume of 10-1 ml of solvent. The corresponding concentrations result in 75-750 mg of complex per ml. Depending on the degree of concentration, highly viscous solutions to pastes result, which are suitable for "Dr. Blade" application or various printing processes. The activation of the applied layer he follows as in Example 1.

Example 8 Electrophoretic deposition of the composite on current collectors of hierarchy III / II and III / 1

120 mg of poly-1 was placed in 3 ml of methanol. To this was added 10 ml of a graphene oxide suspension (4 mg / ml (Graphena)) under sonication. The resulting, stable colloidal solution of the complex (Hierarchy III) was then added to an electrolysis vessel with the omission of an inert electrolyte and electrophoretically applied to the working electrode by applying a potential of -1.4 V to Ag / AgCl (Hierarchy II or I). The electrophoretic The deposition times are listed in the table. As a current collector of the hierarchical level II is a titanium wire mesh with Black Titanium surface (67 wires / cm, wire diameter 65 μιτι, designation: black titanium grade 2 of Hebei Hightop metal mesh, China, where a flexible variant (B2) and a rigid variant (B1) Depending on the amount of electrophoretically deposited composite material, a 0.7 mm thick graphite electrode is used as current collector of hierarchical level I as described in Example 1. In the table below

a) flat carbon electrode

b) titanium wire mesh electrode

bl: Rigide titanium wire mesh electrode (due to extensive wiring of the wires, the electrode shows reduced flexibility)

b2: Flexible titanium wire mesh electrode

Example 9 Production of a Hierarchical Current Collector System (Type: I / II / III) Using the Poly-1 Graphene Oxide Composite (Hierarchy III), Oxidized "Vapor-grown Carbon Fiber" (Hierarchy II) and Graphite Electrode (Hierarchy I) Production of the anoxidised "vapor grown carbon fiber" (Hierarchy II)

300 mg VGCF {Showa Denko, product number 09-03-048) were dispersed in 60 ml of a mixture of H2SO4 (99.9%) / HNOs (65%) (3/1) and refluxed for 24 hours. The solution was then neutralized with aqueous KOH solution. The resulting precipitated, oxidized VGCF were isolated by filtration and washed with water.

Production of Hierarchy II / III Composite Material:

The oxidized VGCF (Gen II) was finally redispersed in water and this solution was added to the composite dispersion (Gen III) prepared as in Ex. 1) to give the poly-1 / GO composite shown in the table below (6.3 mg / ml) interspersed with ox-VGCF.

Establishment of Hierarchy l / ll / lll

The VGCF composite colloidal solution was slowly and continuously applied from an automatic syringe to a heated graphite electrode. In principle, the procedure is similar to that described in Example 1, but the composite now additionally contains VGCF and the stepwise application / heating has been replaced by a continuous application / heating.

A: poly-1 / GO / ox-VGCF (3/1 / 0.75) weight ratio

B: poly-1 / GO / ox-VGCF (3/1/0) weight ratio

Claims

claims

1 . Electrode matehal in the form of a colloidal solution of a molecular complex comprising at least one maximum nanoscale redox-active organic oligomer and / or polymer and at least one nanoscale graphitic material, wherein these in a weight ratio of redox-active oligomer and / or polymer and graphitic material from 0.5: 1 to 20: 1, such as 1: 1 to 20: 1, and wherein the redox-active organic oligomer and / or polymer forms a complex with the graphitic material, and wherein this electrode material, no heavy metals / heavy metal ions or transition metals and their ions.

2. The electrode material according to claim 1, wherein the oligomers and / or polymers are present at least partially as dendrimers.

3. The electrode material according to claim 1, wherein the graphitic material is at least one selected from graphene, graphene oxide, at least partially oxidized CNTs or at least partially oxidized VGCNFs, in particular graphene oxide, such as graphene oxide reduced graphene oxide. 4. The electrode material according to claim 1, wherein the redox-active organic oligomer and / or polymer comprises at least two predominantly cathodic electrophoretic groups from the classes of electrophoretic groups of aliphatic or aromatic N-oxides, 9-alkyl and aryl-carbazoles, 1, 4. Di-Al-kyloxy and aryloxy-2,5-tert-butylbenzenes, benzoquinone diimines, N-alkylphenothiazines or at least two electrophore groups of predominantly anodic character selected from the classes of electrophore groups from bipyridinium salts, quinones, anthachinones or aromatic 1,

4 or 1, 2 dioxo compounds, aromatic tetracarboxylic diimides, aromatic dicarboxylic acid salts, benzylic or aromatic disulfides.

5. Electrode material according to one of the preceding claims, wherein these oligomers and / or polymers have multiple, localized or conjugated, reversibly oxidizable / reducible electrophores, in particular with at least two Electrophoresis groups each capable of being charged or discharged with one or more electrons selected from the following groups of electrophoreses:

6. The electrode material according to one of the preceding claims, wherein this additionally contains a binder polymer, or a pore-forming polymer such as polyvinylidene fluoride, in an amount of 1 to 10 weight percent based on the redox polymer.

7. An electrode material according to one of the preceding claims, wherein the electrode material is one for an electrode of an electrochemical cell, in particular accumulator.

8. A method for producing an electrode comprising an electron material according to any one of claims 1 to 7 comprising

applying the electrode material in the form of a colloidal solution to a current collector;

Removing the solvent while maintaining the molecular complex structure of the electrode material of the graphitic material and the redox-active organic oligomer and / or polymer on the current collector.

9. The method of claim 8, wherein the graphitic material comprises or consists of graphene oxide, further comprising the step of chemically reducing, in particular, the electrochemical reduction, such as by electrocatalytic reduction, of the graphene oxide present in the electrode material.

10. The method according to any one of claims 8 or 9, wherein the application of the electrode material to the current collector by spraying, imprinting or rophoretisch takes place.

1 1. An electrode comprising an electrode material according to any one of claims 1 to 7 and a current collector which is at least microscale.

12. The electrode of claim 1 1, wherein the current collector is one with carbon fibers, such as in the form of a felt or nonwoven fabric; in the form of a fabric or foam, such as in the form of a 3D carbon foam carrier material, in the form of VGCF, in the form of a wire screen; in the form of a foil or plate.

13. The electrode of claim 1 1 or 12, wherein the electrode is a flexible electrode, in particular one with a carbon film as a current collector and an electrode material with reduced graphene oxide or graphene as graphitic material.

14. Electrochemical cell, in particular accumulator having a cathode and an anode, wherein an electrode material according to one of claims 1 to 8 and / or an electrode according to one of claims 1 1 to 13 at least one of the cathode o- forms the anode.

15. An electrochemical cell according to claim 14, wherein the cathode and the anode comprises an electrode material according to any one of claims 1 to 8.

16. An electrochemical cell according to any one of claims 14 or 15, wherein said cell is flexible.

17. An electrochemical cell according to any one of claims 14 to 16, wherein it comprises organic electrolytes, in particular where this one with a cell voltage of> 1, 5 V as> 2 V has.

18. An electrochemical cell according to any one of claims 14 to 17, wherein it has a surface specific capacity of> 20 mAh / cm ² at a total thickness of the electrochemical cell of <1 cm.

19. A process for preparing a viologen-containing oligomer or polymer comprising the steps

- Reacting these two compounds with liberation of a 2,4-dinitroaniline to obtain an oligomeric or polymeric viologen groups

Connection.

20. The method according to claim 19, wherein the reaction takes place after a Zincke reaction.