DE102022105190A1 - Recycling method for components of electrochemical energy storage and recycling device therefor - Google Patents

Abstract

The invention relates to a recycling process for components of electrochemical energy stores, namely batteries with electrodes, which have electrode carrier foils and an electrode coating applied thereto, with the steps a) comminution (16) of battery material, such as production rejects, active and /or deactivated batteries or battery cells, in battery comminuted material, which comprises particles of the electrode carrier foils and particles of the electrode coatings, b) mechanical deagglomeration (18) of the electrode coating particles contained in the battery comminuted material, the step of mechanical deagglomeration (18) being long and/or intensive is carried out until the maximum size of the particles of the electrode coatings no longer exceeds 100 µm in the mass-related mean, and the electrode coatings are crushed to such a particle size distribution that the mean diameter of the particles of the electrode coatings after mechanical deagglomeration is at most 1/10 of the mean size of the Particles of the electrode carrier foils, based on the maximum Feret diameter of the particles of the electrode carrier foils.Furthermore, the invention relates to a recycling device for carrying out this method.

Description

The invention relates to a recycling method for components of electrochemical energy stores, namely batteries, according to the preamble of claim 1 and a recycling device according to the preamble of claim 22 for carrying out such a recycling method.

The invention deals with the recycling of batteries that have electrodes that are formed with electrode carrier foils and an electrode coating applied thereto. These include, in particular, lithium-ion batteries.

The production of lithium-ion batteries is of enormous importance for mobile and stationary energy storage and thus the realization of the widespread use of renewable energies with a favorable CO ₂ balance. However, the CO ₂ balance of the life cycle of the battery depends to a comparatively large extent on the CO ₂ balance of the raw materials it contains. Efficient recycling of raw materials in energy-efficient processes can have a very positive impact on the CO ₂ balance of mobile and stationary energy storage in lithium-ion batteries. The realization of the saving of large amounts of CO ₂ emissions through a more efficient recycling process for lithium-ion batteries and production scrap materials of lithium-ion batteries is the primary goal of this invention.

Damaged or aged primary and secondary (rechargeable battery) lithium ion batteries and lithium metal batteries (hereinafter collectively referred to as lithium batteries) are also dangerous and therefore difficult to transport, especially when damaged. There are high costs for transport and storage.

• - Elektrische Gefahren durch hohe Spannung, die auch Aktivierungsenergie für weitere exotherme Reaktionen zur Verfügung stellen,
• - Chemische Gefahren durch exotherm reagierende Organik und durch thermisch zersetzbare, fluorhaltige Komponenten, die in Freisetzung von Fluorwasserstoff und weiterer Fluorkomponenten resultieren können, und
• - Brand- und Explosionsgefahr, da interne und externe Kurzschlüsse zu lokaler Erhitzung führen können, so dass sich ein Druck aufbauen kann, der schließlich zur Explosion führt.

Lithium batteries pose the following hazards:

• - Electrical hazards from high voltage, which also provide activation energy for further exothermic reactions,
• - Chemical hazards from exothermically reacting organic matter and from thermally decomposable, fluorine-containing components that can result in the release of hydrogen fluoride and other fluorine components, and
• - Risk of fire and explosion, since internal and external short circuits can lead to local heating, so that pressure can build up, which finally leads to an explosion.

The storage, transportation and recycling of these components is expensive and technically demanding due to these hazards.

• - Von Lithium-Ionen-Batterien geht eine elektrische Gefahr aus, beispielsweise durch Reaktionsaktivierung durch elektrisch gespeicherte Energie in solchen Batterien; insbesondere können in- und externe Kurzschlüsse gealterter, beschädigter oder fehlerhaft gefertigter Batterien gefährliche und sich schnell über Kettenreaktionen ausbreitende Brände mit gefährlichen Abgasen verursachen.
• - Lösungsmittel von in solchen Batterien enthaltenen Elektrolyten sind entzündlich.
• - Eine exotherme Zersetzung fluorhaltiger Komponenten (z.B. Leitsalz LiPF₆ (Lithiumhexafluorophosphat) und Binder PVDF (Polyvinylidenfluorid)) solcher Batterien können bei Brand zur Entstehung von gefährlichem Fluorwasserstoff führen (auch bei Kontakt mit Luftfeuchtigkeit im Recyclingprozess oder bei havarierten Batterien).
• - Kathodische Aktivmaterialien solcher Batterien enthalten z.T. Nickel- und Kobaltoxide und sind kanzerogen.
• - Eine Staub-Explosionsgefahr besteht bedingt durch die Entstehung von Stäuben bei der Aufbereitung solcher Batterien.

When processing lithium batteries, other safety issues must also be taken into account:

• - Lithium-ion batteries pose an electrical hazard, for example through reaction activation by electrically stored energy in such batteries; in particular, internal and external short-circuits in aged, damaged or incorrectly manufactured batteries can cause dangerous fires that spread quickly via chain reactions and produce dangerous exhaust gases.
• - Solvents from electrolytes contained in such batteries are flammable.
• - An exothermic decomposition of fluorine-containing components (e.g. conductive salt LiPF ₆ (lithium hexafluorophosphate) and binder PVDF (polyvinylidene fluoride)) of such batteries can lead to the formation of dangerous hydrogen fluoride in the event of fire (also on contact with atmospheric moisture in the recycling process or with damaged batteries).
• - Some of the cathodic active materials in such batteries contain nickel and cobalt oxides and are carcinogenic.
• - There is a risk of dust explosion due to the formation of dust during the processing of such batteries.

Another problem is that lithium batteries from power tools, e-bikes, mobility scooters and industrial batteries that are returned by consumers or are produced as waste are generated in a decentralized manner. In particular, the undesirable production of rejects from lithium batteries occurs decentrally in the respective factories. Such scrap is particularly critical to store, transport and recycle, since the scrap states have not been brought about in a defined manner. The safety status of the batteries and the necessary protective measures for safe storage and safe transport can therefore neither be planned in advance nor classified later. A high safety risk arises, which, in addition to high risks to health and the environment, also entails high financial risks.

Lithium batteries contain valuable ingredients such as cobalt, nickel, lithium, copper and aluminum. If the batteries are processed in a recycling plant, the transition metals (cobalt, nickel, manganese), lithium, copper and aluminum can be recycled.

Particularly valuable raw materials from the lithium battery and the waste from lithium battery production are bound in the coatings on the electrodes. Conventional recycling processes do not shred the batteries (and the production waste) selectively in the first steps, although - as the present invention has recognized - selective decoating leads to a higher degree of separation and thus to higher recycling efficiency (the higher recovery rate of the valuable substances cobalt, nickel, manganese and copper) as well as a better energy efficiency of the recycling process.

The aim of the present invention is to achieve a decentralized conversion of lithium batteries that are no longer required or defective into a transportable state in functional integration by carrying out a selective deagglomeration of the electrode coatings.

The present invention has recognized that selective deagglomeration is advantageous for the following reasons: In battery recycling, valuable raw materials, such as in particular cobalt, nickel, lithium, graphite, copper, aluminum, manganese, iron, plastics and organic carbonates of the electrolyte, should be used as efficiently as possible as little energy as possible in the material cycle.

However, since metals, plastics, other organic components and graphite generally require different recycling processes, it is necessary to separate the materials cleanly before producing intermediate products that can be used industrially.

The present invention has also recognized that the fractions of the various materials (material fractions) should be concentrated as far as possible without losing or devaluing substantial amounts of material. In particular, the recovery of lithium and graphite is mostly sacrificed in the prior art to the easy recovery of cobalt and nickel. Graphite is oxidized by thermal treatment, incinerated or disposed of as filter cake. Lithium is often lost in the slag from pyrometallurgical processes or in the flue dust from smelting processes.

The deagglomeration separates the various material particles made of graphite, lithium metal oxides (or other cathodic battery active materials) and aluminum and copper foils (both current collector foils) connected by a binder, so that the individual particles of the coating materials graphite and cathodic active material are as small as possible. Only when the coating materials are as small as possible, as decoated as possible and as isolated as possible can they be separated from one another and from the current collector foils particularly well on the basis of their physical properties, such as density (special case: buoyancy), particle size, flow behavior or surface properties.

In the prior art, existing bonds between the current collector (aluminum and copper foils) and the coating material (Li, Ni, Co-containing oxides and graphite) are broken either by burning the binder in thermal processes or by mechanical comminution processes.

When the binder burns, it decomposes along with the electrolyte and parts of the graphite. These components can then no longer be recovered and the recycling efficiency is lower. In addition, toxic and chemically aggressive fluorine compounds are formed, which have to be laboriously washed out of the exhaust gas.

In conventional mechanical processes, e.g. two- to three-stage crushing, all materials are crushed together to a similar final particle size. Not every piece of foil is stressed several times, so that 10-30% of the valuable coating materials remain adhering to the current collector foils and are thus discharged in the foil fraction of the recycling process.

In addition, in conventional processes, the current collector foils (Cu, Al) are also crushed and thus impurities of Cu and Al that cannot be sieved out are formed in the finer fractions of the separated coating materials.

Traditionally, battery recycling is only possible in a few places with limited recycling efficiency and higher energy consumption. Damaged and aged batteries must also be transported to these locations and stored there until they can be processed.

In order to get to the recycling site, defective batteries traditionally have to be sent for recycling in special containers with a filling medium. The transports often require special permits. Furthermore, transport containers are often only approved for a specific battery system and increase the weight and volume-based transport costs.

Before recycling, the batteries are stored. In these camps, spontaneous combustion often occurs, leading to major fires.

Even after the conventional shredding of batteries that have not been deactivated beforehand in ambient air or under nitrogen, there are still galvanic elements - due to the functional residual coatings still present on the current collectors - which can lead to local short circuits and cause further exothermic reactions. This sets off chain reactions and fires can continue to break out during or after shredding and in the warehouse.

Conventionally, batteries or battery cells are also largely pyrometallurgically processed for recycling (in particular by melting and slag separation) or processed in a combination of thermal process steps and hydrometallurgy. On the one hand, these processes are energy-intensive and, on the other hand, they are not suitable for the recovery of lithium and aluminum based on the current state of the art, and they also cause emissions in the form of fluorine-containing waste gases.

1. (a) Zerkleinern der Batterien, so dass Zerkleinerungsgut erhalten wird,
2. (b) Inaktivieren des Zerkleinerungsguts durch Trocknen, so dass ein inaktiviertes Zerkleinerungsgut erhalten wird, wobei
3. (c) das Trocknen bei einem Druck von höchstens 300 hPa und höchstens 80 °C erfolgt und
4. (d) das inaktivierte Zerkleinerungsgut in einen Transportbehälter abgefüllt wird.

Another known solution EP 3 289 627 B1 is a procedure for treating used lithium batteries with the steps:

1. (a) crushing the batteries so that crushed material is obtained,
2. (b) inactivating the comminuted material by drying so that an inactivated comminuted material is obtained, wherein
3. (c) the drying is carried out at a pressure of not more than 300 hPa and not more than 80 °C and
4. (d) the inactivated comminuted material is filled into a transport container.

In paragraph [0009] of the patent EP 3 289 627 B1 it is described that the inactivation by drying the material to be comminuted takes place to the extent that so much electrolyte can be removed that an electrochemical reaction is no longer possible or only possible to a negligibly small extent.

The disadvantage of this solution is that even under an inert atmosphere during the comminution/processing of still active, charged batteries in the comminution room, the highly exothermic fire reactions described above can occur with the formation of toxic gases containing fluorine.

The disadvantage of this solution according to EP 3 289 627 B1 is also that the material to be comminuted can be exposed to an oxygen- and/or moisture-containing ambient atmosphere immediately after drying. During storage and transportation of the materials, toxic and corrosive by-products can be formed in the in EP 3 289 627 B1 described transport container come.

The end EP 3 312 922 B1 known recycling methods for treating used batteries, in particular rechargeable batteries, does not disclose a transport container. Here, however, the material has to be temporarily buffered in intermediate containers, so that these reactions can occur in the intermediate containers.

The coupling of these disadvantages, i.e. the processing of non-discharged batteries with filling them into transport containers with a potentially moist, oxygen-rich air atmosphere, is potentially dangerous. This is due to the fact that in the comminution products of lithium batteries which have not been deactivated via a complete deep discharge, the reactive metal lithium (in its metallic form) is present on the graphitic anode. This metal reacts strongly exothermically with oxygen or water (from atmospheric moisture) and these reactions can lead to spontaneous self-ignition of the transport containers.

Another disadvantage of the method after EP 3 312 922 B1 is that the energy required to deform metals during mechanical comminution is partly dissipated as heat. In comminution processes, this leads to heating of the material to be comminuted. Battery modules are encased in sheet metal and contain metal components. The housings of the battery cells also consist largely of formed sheet metal.

A warm material to be crushed results in particular from the rapid crushing of larger quantities of batteries, which is desirable for economic reasons. With the stored heat, this comminution brings with it the activation energy for the above-described decomposition reactions of the electrolyte salt and any residues of the organic carbonates of the electrolytes that may remain in the comminution in the presence of atmospheric moisture or atmospheric oxygen.

Another disadvantage of the methods described above with material transport and transport containers is that carcinogenic products (e.g. cathode powder with hazard warning category 350, 350i, 351) have to be filled and transported. These bagging, packaging and decanting operations contain the potential for dust and carbon nanotubes (CNTs) to escape.

Another disadvantage of the prior art EP 3 289 627 B1 as well as DE 10 2012 024 876 A1 is that during the During transport and storage, the cohesive bulk material and crushed material is compacted and subsequently forms bulk material bridges, so that defined, low-dust emptying is difficult without human intervention.

Another disadvantage is that the throughput of the system with permanently installed mixers in the modular concept shown in decentralized containers is determined by the drying speed.

The economically thinking user will use the minimum drying criterion of reduced fire risk to increase the system throughput (see e.g EP 3 289 627 B1 and DE 10 2012 024 876 A1 ) as a process criterion to determine the minimum drying time and maximize the system throughput.

Many types of lithium batteries contain cobalt and nickel oxides or their compounds that are classified as carcinogenic. Aging or damaged lithium battery cells, battery modules and battery systems must therefore be recycled. This utilization must be recycling with a high proportion of material utilization in order to decisively improve the CO ₂ balance of battery production.

Recycling lithium batteries is not trivial due to the battery's chemical, electrical and fire hazards. The transport of aged and damaged batteries in particular is complex and dangerous. Again and again, fires occur in transporters, warehouses and recycling facilities due to self-ignition and poor process management. The goal of recycling lithium batteries is the separation of all valuable components in order to be able to process them separately and particularly efficiently.

1. a) keine mit Wasser und Luftfeuchtigkeit reaktiven Reste metallischen Lithiums im desaktivierten Gut vorliegen,
2. b) kein metallisches Lithium mehr mit den organischen Carbonaten des Batterieelektrolyten reagieren kann, denn dieses würde bedeuten:
   1. i) Bindung von Lithium in Carbonatverbindungen, die schwieriger in standardisierten metallurgischen Prozessen zurückgewonnen werden können,
   2. ii) Abreaktion der organischen Carbonate DMC (Dimethylcarbonat), EMC (Ethylmethylcarbonat), EC (Ethylencarbonat), die dann nicht weiter als Bestandteile des Batterieelektrolyten zurückgewonnen werden können, und
   3. iii) Bildung entzündlicher Gase, bspw. Methen, Methan oder Propan, als Nebenprodukte,
3. c) das Lithium während der folgenden metallurgischen Aufbereitungsschritte gezielt und konzentriert aus den Metalloxiden des kathodischen Aktivmaterials extrahiert werden kann, während das anodische Graphit vorab abgetrennt werden kann,
4. d) das Lithium die Graphitfraktion nicht verunreinigt, und das Graphit somit sauber und effizient rückgewinnbar wird.

The present invention has recognized that it is advantageous that all of the lithium stored in the (partially) charged state in the anode can be safely converted into the metal oxide compound of the cathode, so that

1. a) no residues of metallic lithium reactive with water and humidity are present in the deactivated goods,
2. b) metallic lithium can no longer react with the organic carbonates of the battery electrolyte, because this would mean:
   1. i) binding of lithium in carbonate compounds, which are more difficult to recover in standard metallurgical processes,
   2. ii) Reaction of the organic carbonates DMC (dimethyl carbonate), EMC (ethyl methyl carbonate), EC (ethylene carbonate), which can then no longer be recovered as components of the battery electrolyte, and
   3. iii) formation of flammable gases, e.g. methene, methane or propane, as by-products,
3. c) the lithium can be extracted in a targeted and concentrated manner from the metal oxides of the cathodic active material during the subsequent metallurgical processing steps, while the anodic graphite can be separated off beforehand,
4. d) the lithium does not contaminate the graphite fraction, and the graphite thus becomes clean and efficiently recoverable.

The present invention has further recognized that it is advantageous if the inactivation of the batteries can be achieved without the formation of fluorine-containing exhaust gases and without the risk of fire.

The present invention has also recognized that it is advantageous to increase the packing density of the battery materials to be transported.

The present invention has further recognized that it is advantageous to provide dust-free, solvent-free storage, filling and emptying of the battery fragments in transport containers.

The present invention has further recognized that it is advantageous to provide easy filling and emptying of the storage containers (with extremely cohesive bulk material).

The present invention has further recognized that it is advantageous to allow for outdoor storage by preventing moisture from penetrating the battery fragments.

The present invention has also recognized that it is advantageous to achieve high recycling efficiency by preparatory good separation of current collector foil (Ai, Cu) and coating materials (Co, Ni, Mn, Li mixed oxides and graphite) and the selective deagglomeration of the coating materials without thermal decomposition of the binder to allow.

The present invention has also recognized that it is advantageous to achieve high energy efficiency in the recycling process.

The present invention has also recognized that it is advantageous to enable inerted transport with inert gas, nitrogen or vacuum.

The present invention has further recognized that if the organic carbonates are not removed by vacuum drying at a moderate temperature are removed, they react with the conductive salt LiPF ₆ present in the battery to form fluorophosphates (dimethyl fluorophosphate (DMFP) and diethyl fluorophosphate (DEFP)), among other things. These substances are of such concern that they can be used as chemical weapons.

The present invention has further recognized that it is advantageous if the organic reagents are removed so that they cannot react further during storage and transport.

The present invention has also recognized that the danger of comminuted lithium battery fragments is reduced by removing electrolyte, since flammable components have been removed and an flammable atmosphere can therefore no longer form in the containers to be transported.

The invention is therefore based on the object of avoiding the above-mentioned disadvantages of conventional battery recycling.

The invention solves this problem with the features of a recycling method according to claim 1 and with a recycling device with the features according to claim 22.

1. a) Zerkleinerung von Batteriematerial, wie bspw. bei der Produktion von Batterien entstehendem Produktionsausschuss, aktiven sowie desaktivierten Batterien oder Batteriezellen, in Batteriezerkleinerungsgut, das Partikel der Elektrodenträgerfolien und Partikel der Elektrodenbeschichtungen umfasst,
2. b) mechanische Desagglomeration der im Batteriezerkleinerungsgut enthaltenen Partikel der Elektrodenbeschichtungen, vorzugsweise bei Temperaturen unterhalb der Zersetzungstemperatur eines in den Elektroden enthaltenen Binders,
3. c) der Schritt der mechanischen Desagglomeration so lange und/oder intensiv durchgeführt wird, bis die maximale Größe der Partikel der Elektrodenbeschichtungen im massebezogenen Mittel 100 µm nicht mehr überschreitet, und
4. d) die Elektrodenbeschichtungen auf eine derartige Partikelgrößenverteilung zerkleinert werden, dass der mittlere Durchmesser der Partikel der Elektrodenbeschichtungen nach der mechanischen Desagglomeration maximal 1/10 der mittleren Größe der Partikel der Elektrodenträgerfolien, bezogen auf den Maximum-Feret-Durchmesser der Partikel der Elektrodenträgerfolien, beträgt.

The recycling process according to the invention for components of electrochemical energy stores, namely batteries with electrodes that have electrode carrier foils and electrode coatings applied thereto, therefore provides the following steps:

1. a) comminution of battery material, such as production rejects arising in the production of batteries, active and deactivated batteries or battery cells, into comminuted battery material that includes particles of the electrode carrier foils and particles of the electrode coatings,
2. b) mechanical deagglomeration of the particles of the electrode coatings contained in the battery crushed material, preferably at temperatures below the decomposition temperature of a binder contained in the electrodes,
3. c) the step of mechanical deagglomeration is carried out long and/or intensively until the maximum size of the particles of the electrode coatings no longer exceeds 100 μm in terms of mass-related mean, and
4. d) the electrode coatings are crushed to such a particle size distribution that the average diameter of the particles of the electrode coatings after mechanical deagglomeration is at most 1/10 of the average size of the particles of the electrode carrier foils, based on the maximum Feret diameter of the particles of the electrode carrier foils.

In this case, the invention preferably uses an intensive interaction between particles by mixing in order to achieve a small particle size of the particles of the electrode coatings, while the size of the particles of the electrode carrier foils is significantly larger.

The deagglomeration preferably takes place through the input of mechanical energy.

Preferably, the particle size distribution of the cathodic electrode coatings after deagglomeration has a median value x ₅₀ that is smaller than four times the median value x ₅₀ of the particle size distribution of cathodic active materials contained in the cathodic electrode coatings contained in the electrode to be recycled. The particle size is measured or determined by analysis of the commercially available active material or by electron micrographs of the electrode structure. A measurement of the particle size while carrying out the method according to the invention is not necessary, but can be provided in a preferred embodiment of the invention. The aforementioned particle size distribution is preferably obtained by deagglomerating for so long and/or so intensively that it occurs. The duration and/or intensity of the deagglomeration are determined in advance, e.g. experimentally, and values for the duration and/or intensity of the deagglomeration as a function of material quantities and material compositions are stored in one or more tables, which are used when the method is carried out in order to determine the required duration and/or intensity of deagglomeration. The median value x ₅₀ of the particle size distribution of the cathodic electrode coatings after deagglomeration is preferably less than 10 to 20 times the median value x ₅₀ of the particle size distribution of cathodic active material contained in the cathodic electrode coatings in the electrode of lithium iron phosphate batteries to be recycled.

The particle size of the cathodic active material is in turn measured or determined by analysis of the commercially available active material or by electron micrographs of the electrode structure, with measurement of the particle size not being necessary when carrying out the method according to the invention, but in a preferred embodiment design of the invention can be provided. The aforementioned particle size distribution is preferably obtained by deagglomerating for so long and/or so intensively that it occurs. Again, the duration and/or intensity of the deagglomeration is determined in advance, e.g. experimentally, and values for the duration and/or intensity of the deagglomeration as a function of material quantities and material compositions are stored in one or more tables, which are used when the method is carried out, to determine the required duration and/or intensity of deagglomeration.

The focus here is on the deagglomerated individual particles or the particle size distribution of the active material before coating.

The invention preferably provides that the binder is not thermally decomposed prior to deagglomeration. This means that the mechanical deagglomeration is preferably carried out at temperatures below the decomposition temperature of the binder.

The processing of non-deactivated battery material is preferably carried out at temperatures above 80° C., which has proven to be advantageous in combination with mechanical deagglomeration.

Preferably, the comminuted battery material is not dried prior to deagglomeration.

The invention preferably also provides that the crushed battery material contains components of the materials of the battery cell casings.

The invention preferably provides that the deagglomeration is controlled or determined on the basis of the porosity and/or pore radius distribution of the particles of the electrode coatings and/or the particles of the electrode carrier foils.

The mechanical deagglomeration is preferably carried out with a specific power input using a deagglomeration device for a period of at least one minute, preferably at least 2 minutes, particularly preferably at least 5 minutes, with at least 50 watts per kilogram, preferably 70 watts per kilogram, particularly preferably 100 watts per kilogram , carried out on battery active materials contained in the crushed material.

According to a development of the invention, a further step, following the deagglomeration, of separating the particles of the electrode coatings from the dried material to be comminuted by sifting and/or sieving is provided.

A development of the invention provides for a drying or recovery of solvent contained in the electrolyte of the battery, preferably organic solvent, in a machine.

According to a development of the invention, the drying is used to also dry out coolants or extinguishing agents, for example water, from a wet comminution preceding the drying.

A development of the invention provides that the steps of comminution and drying are combined and carried out in an explosion-proof manner in a drying chamber of the machine in which negative pressure or vacuum prevails, with explosion protection being provided by monitoring the pressure in this drying chamber. The pressure resistance of the machine is preferably determined in such a way that, in the event of an explosion, the increase in pressure in the machine results in maximum forces acting on the machine that can be tolerated by the machine. Preferably, the operating pressure in this drying space is in the range from one twentieth to one fifth of the crushing strength of the machine.

According to a development of the invention, the duration of drying during operation is determined and controlled as a function of a combination of measured values for the proportion of volatile organic carbon in the drying gas and the absolute pressure and/or the rate of change in the absolute pressure in the drying chamber.

A further development of the invention provides that the galvanic elements of the batteries are deactivated by electrical deep discharge before the comminution, so that an electrochemical reaction is no longer possible.

1. a) Tiefentladen und/oder
2. b) Entfernen des Elektrolyts durch Vakuumtrocknung, vorzugsweise bei einem Druck von 0 bis 600 mbar, vorzugsweise bei Temperaturen <80 °C und/oder
3. c) thermisches Entfernen des Elektrolyts bei Temperaturen >80°C und/oder
4. d) Zerkleinern in wässriger Lösung und/oder
5. e) Zerkleinern in Kühlmittel/Löschmittel und/oder
6. f) Zerkleinern/Vermischen mit einem Bindemittel, bspw. Kalk, Kalkmilch.

According to a development of the invention, it is provided that the materials to be recycled are components of batteries that were once electrically charged and were then deactivated, with the deactivation being effected by

1. a) deep discharge and/or
2. b) removing the electrolyte by vacuum drying, preferably at a pressure of 0 to 600 mbar, preferably at temperatures <80° C. and/or
3. c) thermal removal of the electrolyte at temperatures >80°C and/or
4. d) crushing in aqueous solution and/or
5. e) crushing into coolant/extinguishing agent and/or
6. f) crushing/mixing with a binder, e.g. lime, milk of lime.

The electrolyte can be removed either by vacuum drying at a pressure of 0 to 600 mbar or by thermal removal of the electrolyte at temperatures >80°C or first by vacuum drying at a pressure of 0 to 600 mbar and subsequent thermal removal of the remaining electrolyte at temperatures > 80°C.

A development of the invention provides that the materials to be recycled are production rejects from the production of electrodes for lithium batteries or from lithium battery production, preferably from lithium batteries that were never electrically charged.

Advantageously, batteries that have never been electrically charged do not need to be deactivated since the battery materials are already electrochemically inactive.

According to a further development of the invention, the batteries to be recycled have composite materials of electrode assemblies including electrode carrier foils with electrode coatings and separator foils applied thereto.

1. a) ein Mischwerkzeug zum mechanischen Durchmischen und Auflockern des Batteriezerkleinerungsguts,
2. b) eine Anschlussmöglichkeit für eine aktive Austragshilfe oder eine festinstallierte aktive Austragshilfe oder ein Förderaggregat zum Austragen des Batteriezerkleinerungsguts und
3. c) Mittel, um den Transport-Mischer zu inertisieren und/oder zu evakuieren und wiederholbar im mit Batteriezerkleinerungsgut befüllten Zustand des Transport-Mischers ohne Staubentwicklung dem Transport-Mischer Gas aufzugeben, aus dem Transport-Mischer Gas abzulassen und/oder im Transport-Mischer Vakuum anzulegen.

A development of the invention provides that, after the comminution, the battery comminution is stored and transported in a gas-tight and dust-tight transportable transport mixer, the transport mixer having:

1. a) a mixing tool for mechanical mixing and loosening of the battery crushed material,
2. b) a connection option for an active discharge aid or a permanently installed active discharge aid or a conveyor unit for discharging the battery shredded material and
3. c) Means for rendering the transport mixer inert and/or evacuating it and, when the transport mixer is filled with battery comminution material, to feed gas to the transport mixer, to let gas out of the transport mixer and/or in the transport mixer, without generating dust apply vacuum.

The transport mixer is characterized in that it can be transported in the filled state without further outer packaging, preferably with a crane, with a forklift truck, by road, by sea and/or by rail. For example, the transport mixer includes a sea freight container, also referred to as an ISO container, for example in the form of a 20-foot ISO container or a 40-foot ISO container, as it is, for example, basic in the ISO standard 668 is fixed. It preferably includes container corners (e.g. according to ISO standard 1161) and/or forklift lugs so that it can be handled using a forklift. The container contains equipment for mixing the battery crushed material, a dust-tight, in particular airtight, closable filling opening for filling in the battery crushed material and a conveyor unit for discharging the battery crushed material through a dust-tight, in particular airtight, closable discharge opening and, if necessary, facilities for inerting and/or evacuating the Arranged interior of the container and / or facilities for heating the interior.

The use of such a special container is advantageous since it ensures the transport and storage of large quantities of battery crushed material in a cost-effective and largely safe manner. Due to the large volume of such a container, there is a large space for the transport and storage as well as for mixing the battery crushed material. The number of decanting processes can be kept low due to the multifunctionality of such a transport mixer. This is advantageous because it means that any dust that escapes during decanting is not released into the environment. Since the battery comminuted material often contains carcinogenic materials, their distribution to the environment via dust is disadvantageous and can be prevented by using such a transport mixer.

1. a) die Langzeittrocknung vor der Desagglomeration oder
2. b) die Desagglomeration vor der Langzeittrocknung oder
3. c) die Desagglomeration und die Langzeittrocknung gleichzeitig durchgeführt werden. Die Desagglomeration findet vorzugsweise durch Intensivmischung statt.

According to a further development of the invention, the battery comminuted material is dried for a long time in the transport mixer, for example over a period of more than 30 minutes

1. a) long-term drying before deagglomeration or
2. b) the deagglomeration before long-term drying or
3. c) the deagglomeration and the long-term drying are carried out simultaneously. The deagglomeration preferably takes place by intensive mixing.

A further development of the invention provides that drying heat is introduced into the transport mixer, e.g. by introducing a temperature control liquid into a double jacket surrounding the drying space for temperature control of the walls of the drying space and/or by heating a heating jacket surrounding the drying space.

According to a development of the invention, the drying heat is supplied over a longer period of time, for example more than 30 minutes, and at a low temperature level, for example at a temperature below 100°C, preferably below 80°C and particularly preferably below 60°C. The drying heat is preferably supplied by using a heat pump and/or using waste heat from units and processes other than units and processes used in the recycling process.

Such low temperatures lead to fewer undesirable side reactions due to the decomposition of conductive salt and organic carbonates and additives. For example, the formation of hydrogen fluoride in the gas atmosphere of the transport mixer during post-drying can be kept below 100 ppm, preferably below 30 ppm, in the offgas stream.

Such low temperatures lead to higher energy efficiency, since heat pumps operate with a higher coefficient of performance at smaller temperature differences and the supply of the evaporation enthalpy of the solvent of the electrolyte, which is necessary for evaporation, can be carried out in a particularly energy-efficient manner.

A development of the invention provides that after the steps of comminution and intensive mixing, the transport mixer is used for post-drying.

According to a development of the invention, the transport mixer is connected to a drying system.

A development of the invention provides that the transport mixer is connected to a drying and condensation circuit of a preparation plant for crushing the battery material and for electrolyte recovery via a feed system for feeding in the battery material or via a gas pipe connection.

1. a) eine Einrichtung zur Drucküberwachung des Druckes im Trocknungsraum,
2. b) eine Einrichtung zur Überwachung von flüchtigen organischen Kohlenstoffen im Trocknungsgas, und/oder
3. c) eine Einrichtung zur Sauerstoffüberwachung im Trocknungsgas und/oder Trocknungsraum aufweist.

According to a further development of the invention, it is provided that the transport mixer is protected against an explosion by means of an explosion protection device

1. a) a device for pressure monitoring of the pressure in the drying room,
2. b) a device for monitoring volatile organic carbons in the drying gas, and/or
3. c) has a device for monitoring the oxygen in the drying gas and/or drying room.

A further development of the invention provides that in the transport mixer the battery material is transported by road, rail and/or ship to a processing location and is connected there to a processing system, in particular a drying system of the processing system, and/or emptied into this processing system becomes.

1. a) eine Zerkleinerungseinheit zur Zerkleinerung von deaktiviertem oder nicht elektrochemisch aktivem Batteriematerial, wie bspw. bei der Produktion von Batterien entstehendem Produktionsausschuss, desaktivierten Batterien oder Batteriezellen, in Batteriezerkleinerungsgut, das Partikel der Elektrodenträgerfolien und Partikel der Elektrodenbeschichtungen umfasst,
2. b) eine Desagglomerationsvorrichtung zur mechanischen Desagglomeration der im Batteriezerkleinerungsgut enthaltenen Partikel der Elektrodenbeschichtungen, vorzugsweise ein Intensivmischer zur Intensivmischung dieser Partikel, vorzugsweise bei Temperaturen unterhalb der Zersetzungstemperatur eines in den Elektroden enthaltenen Binders,
3. c) wobei die Desagglomerationsvorrichtung eine Steuerungseinrichtung aufweist, die derart ausgebildet ist, um die mechanische Desagglomeration so lange und/oder intensiv durchzuführen, bis die maximale Größe der Partikel der Elektrodenbeschichtungen im massebezogenen Mittel 100 µm nicht mehr überschreitet und die Elektrodenbeschichtungen auf eine derartige Partikelgrößenverteilung zerkleinert ist, dass der mittlere Durchmesser der Partikel der Elektrodenbeschichtungen nach der mechanischen Desagglomeration maximal 1/10 der mittleren Größe der Partikel der Elektrodenträgerfolien, bezogen auf den Maximum-Feret-Durchmesser der Partikel der Elektrodenträgerfolien, beträgt.

The object on which the invention is based is also achieved by a recycling device that is set up for recycling components of electrochemical energy stores, namely batteries with electrodes that have electrode carrier foils and an electrode coating applied thereto, the recycling device having:

1. a) a comminution unit for comminuting deactivated or non-electrochemically active battery material, such as production rejects, deactivated batteries or battery cells arising in the production of batteries, into battery comminution material which comprises particles of the electrode carrier foils and particles of the electrode coatings,
2. b) a deagglomeration device for mechanical deagglomeration of the particles of the electrode coatings contained in the battery material to be comminuted, preferably an intensive mixer for intensive mixing of these particles, preferably at temperatures below the decomposition temperature of a binder contained in the electrodes,
3. c) the deagglomeration device having a control device which is designed to carry out the mechanical deagglomeration long and/or intensively until the maximum size of the particles of the electrode coatings no longer exceeds 100 μm in terms of mass-related mean and the electrode coatings are comminuted to such a particle size distribution is that the average diameter of the particles of the electrode coatings after the mechanical deagglomeration is at most 1/10 of the average size of the particles of the electrode carrier foils, based on the maximum Feret diameter of the particles of the electrode carrier foils.

According to developments of the invention, this recycling device has means for carrying out the method steps according to the invention.

Developments of the invention also result from the claims, the description and the drawings. The aforementioned features and their advantages and combinations of several features are exemplary and can alternatively or come into effect cumulatively, without the advantages necessarily having to be achieved by embodiments according to the invention. Further features can be found in the drawings. The combination of features of different configurations of the invention or features of different claims is also possible, deviating from the selected dependencies of the claims, and is hereby proposed. This also applies to those features that are shown in separate drawings or are mentioned in their description. These features can also be combined with features of different claims. Likewise, features listed in claims can be omitted for further embodiments of the invention.

• 1 ein Ausführungsbeispiel eines erfindungsgemäßen Recyclingverfahrens in schematischer Darstellung.

In the drawing shows:

• 1 an embodiment of a recycling process according to the invention in a schematic representation.

1 shows an exemplary embodiment of a recycling method 10 according to the invention, which is carried out in a modular recycling device for carrying out the method steps according to the invention. The steps of deactivating the batteries by discharging, the electrolyte recovery, the material preparation by separating the materials and the metallurgical further processing of the valuable metals are decoupled from each other, so that depending on regional material occurrence and material quantities, on the condition of the batteries or the battery production committee and on the downstream Processes different process routes can be combined. For example, a decentralized discharge can take place first, then an electrolyte recovery and then products from the battery recycling process can be fed into a pyro or hydro route.

The modules of the modular system depend on the desired capacity and combine the process steps set out below.

1. Disabling the Batteries - Step 12:

If the battery components or the battery are electrochemically charged, they are first electrochemically deactivated. If the battery elements are not yet electrochemically activated or have become electrochemically inactive in some other way, deactivation is not necessary.

The lithium battery production waste is not electrochemically active before the process step of formation and initial charging. A battery can disable itself by self-discharging to zero volts.

a) Deactivating the batteries through deep discharge:

The deactivation of the batteries is preferably achieved before the shredding by a deep discharge of the batteries with a subsequent short circuit. The short-circuit lasts for a period of time that is determined such that relaxation behavior no longer occurs after this time, e.g. more than 6 hours, more than 12 hours or preferably more than 24 hours.

The batteries are discharged to rob them of stored electrical energy that could otherwise activate further exothermic reactions. Discharging takes place, for example, via an electrical load (resistor, consumer) or feedback into the power grid. Furthermore, the discharging can take place via an ion-conducting liquid, which is used in particular when the batteries can no longer be discharged in any other way.

The discharge is preferably temperature-controlled. For example, the discharge is interrupted if the measured outside temperature exceeds 60°C and a cooling process starts if the temperature exceeds 100°C. In one embodiment, the cooling process can also take place via immersion in a preferably cooled basin filled with deionized water. Deionized water is non-conductive, so cell/contact electrolysis is not possible. An ion exchanger and a cooling device are preferably connected in circulation to a basin provided for the cooling process, so that ions brought in by dirt and batteries are removed from the water.

In the event of self-ignition of the battery, there is sufficient extinguishing water to prevent flash fires and extinguish the battery by cooling it down.

With such external cooling, the discharge can be up to a factor of 10 faster, since the heat generated is continuously dissipated.

Preferably, after reaching zero volts between the electrodes of the battery, the short is connected under deionized water and the battery is left shorted in a cooldown/relaxation pool until heat is no longer evolved in that pool. In one embodiment, the battery tanks are connected in series to serve multiple tanks with an ion exchanger, activated carbon, and a refrigeration unit. Preferably then the water inlet temperature and compared the water discharge temperature. When both temperatures are the same, the reaction is complete. In this way, the dissipated energy per battery can also be balanced during the discharging process and the discharging speed can be maximized in a targeted manner.

Another option is to place a thermocouple on the battery and place a thermocouple in the water. If there is no temperature gradient, the reaction is complete.

Most of the lithium in a secondary lithium-ion battery is re-intercalated into the metal lattice of the transition metal oxides and is no longer present in its reactive metallic form on the graphite electrode.

1. b) Deaktivieren der Batterien durch Entfernen des Elektrolyts durch Vakuumstrocknung bei Drücken vorzugsweise zwischen 0 und 600 mbar und vorzugsweise bei Temperaturen unter 80 °C.
2. c) Deaktivieren der Batterien durch thermische Vorbehandlung:
   • Alternativ erfolgt eine elektrochemische Deaktivierung durch Erhitzung der Batterie oder der zerkleinerten Batterie auf Temperaturen über 80 °C und Austrocknen des Elektrolyts.
3. d) Deaktivieren der Batterien durch Einfrieren des Elektrolyts:
   • Alternativ erfolgt eine zeitweise elektrochemische Deaktivierung durch Einfrieren des Elektrolyts der Batterie auf Temperaturen unter seinen Gefrierpunkt.

After this step, only deactivated galvanic elements are left. There is no electrochemical potential difference between the electrodes. Chemical equilibrium has been reached. Electrochemical reactions are not possible in this state.

1. b) deactivating the batteries by removing the electrolyte by vacuum drying at pressures preferably between 0 and 600 mbar and preferably at temperatures below 80°C.
2. c) Deactivating the batteries by thermal pre-treatment:
   • Alternatively, electrochemical deactivation occurs by heating the battery or crushed battery to temperatures above 80°C and drying out the electrolyte.
3. d) Disabling the batteries by freezing the electrolyte:
   • Alternatively, temporary electrochemical deactivation occurs by freezing the battery's electrolyte to temperatures below its freezing point.

2. Disassembly - Step 14:

A dismantling module with tools, personal protective equipment and suitable lifting tables is provided to dismantle the deactivated batteries to module or stack size. For smaller capacities, discharging and dismantling are preferably accommodated in a common module.

This module in particular is preferably designed independently of the other modules with the highest mobility properties. Very mobile designs are, for example: ISO containers, truck trailers, semi-trailers, a fixed truck body.

3. Shredding - Step 16:

Deactivated battery systems, battery modules or battery cells are placed in a shredding unit A via a lock 15 flushed with inert gas or which can be evacuated. The comminution unit A is preferably designed to be pressure-shock-proof, gas-tight and vacuum-proof.

1. a) die Bildung eines zünd- oder explosionsfähigen Gemisches mit den im Elektrolyten enthaltenen organischen Carbonaten (bspw. Dimethylcarbonat, Ethylmethylcarbonat) zu verhindern und
2. b) den Wassergehalt der Atmossphäre weitestmöglich abzusenken und eine exotherme Reaktion der fluorhaltigen Leitsalze des Elektrolyten und des teilweise noch metallisch auf der Graphitelektrode abgelagerten Lithiums mit ansonsten vorhandener Luftfeuchtigkeit zu unterbinden und die leichtflüchtigen Elektrolytbestandteile wasserfrei zurückzugewinnen.

In addition, comminution is carried out under an inert gas atmosphere, in a vacuum or in an atmosphere supersaturated with volatile organic carbons

1. a) to prevent the formation of an ignitable or explosive mixture with the organic carbonates contained in the electrolyte (e.g. dimethyl carbonate, ethyl methyl carbonate) and
2. b) to reduce the water content of the atmosphere as much as possible and to prevent an exothermic reaction of the fluorine-containing conductive salts of the electrolyte and the lithium, which is still partially metallically deposited on the graphite electrode, with the otherwise existing humidity and to recover the volatile electrolyte components anhydrous.

Inerting with nitrogen is preferably carried out in a functional integration with cooling of the comminution space by injecting liquid nitrogen. The expansion of the liquid nitrogen extracts heat from the comminution space and thus further reduces the reactivity in the comminution space.

In one embodiment of the invention, the gas-tight and preferably vacuum-tight shredder is connected directly to the electrolyte recovery. In this way, the organic solvents escaping when the cell is opened can be evaporated directly via vacuum. The heat of comminution contributes to the amount of energy for the enthalpy of vaporization, while the comminution space is cooled directly by removing the enthalpy of vaporization. It can be comminuted more intensively and quickly without having to worry about the negative side effects of temperature-induced conversion of the conductive salt into hydrogen fluoride.

In a preferred embodiment of the invention, the comminution is carried out under vacuum. The explosion protection in this embodiment is simple and very effective. At the first level, there is no oxygen for ignition due to the constant evacuation. On the second level, an explosion usually leads to a maximum expansion in volume by a factor of 10 in relation to the initial pressure. From an absolute pressure of less than 100 mbar, the maximum achievable explosion pressure is then one bar, which only corresponds to the ambient pressure and is therefore harmless.

4. Selective, non-thermal deagglomeration of the black mass components - Step 18:

After comminution, the so-called black mass components of the battery are deagglomerated in a deagglomeration device B by introducing mechanical energy. This can be done, for example, by mixing in a deagglomeration device.

"Black mass" is understood to mean the powdered raw material concentrate, which is recovered from the coatings on the electrodes (anodes and cathodes). In addition to the current collector foils made of copper and aluminum, the electrodes of the batteries consist primarily of metals such as lithium, manganese, cobalt and nickel as well as graphite and a binder. The crushed battery material is treated to produce black matter, which contains a lot of these metals. The black mass mainly consists of the coating materials of the electrode foils and small amounts of aluminium, copper and mostly polyethylene as well as other impurities from the recycling process. The black mass contains valuable raw materials such as lithium, graphite, cobalt, copper, nickel and manganese.

In the case of cathodic active materials, deagglomeration takes place with such a high energy input and such a process time that the median value x ₅₀ of the particle size distribution after deagglomeration is less than four times (preferably twice) x ₅₀ of the particle size distribution of the industrial starting product of the cathodic active material.

As an exception, the deagglomeration of batteries with active materials with a median value x ₅₀ of the particle size distribution <5 µm, for example based on lithium iron phosphate chemistry, takes place to 10-20 times the median value x ₅₀ of the particle size distribution of the industrial starting product of the cathodic active material.

The deagglomeration also takes place in such a way that the maximum particle size of the coating components after deagglomeration does not exceed 100 μm (preferably 50 μm) on average.

This step opens interparticle pores, which facilitates the evaporation of the low-boilers of the electrolyte and residual water from underwater comminution by reducing the pressure losses and diffusion resistances through the pores and increasing the free particle surface. The Stefan tube effect, which occurs in the pores during evaporation, is minimized. Furthermore, the counteracting effect of capillary condensation on evaporation is reduced by reducing the intraparticle pores.

In the case of incorrect, incomplete deactivation due to deep discharge, removal of electrolyte or in the case of only temporary deactivation due to prior freezing, galvanic elements are also separated from one another in the deagglomeration step and mixed on a particulate level. A reaction of the chemical potential differences thus takes place in the smallest space with infinitesimally small energy exchange. A punctiform heating of the active material by micro-short circuits and the subsequent self-ignition of the material can thus be prevented.

In contrast to finer comminution, in which all the components of the battery would be used and comminuted, the active material is selectively deagglomerated here by intensive mixing. The agglomerates of the coating materials are mainly crushed, while the elastic aluminum and copper foils are not crushed to the same extent and the heavy components are not crushed, but on the contrary act as autogenous grinding media.

wobei P_Desagglo die Leistungsaufnahme des Desagglomerationaggregats und m_Schwarzmasse die Masse der Schwarzmasse sind.The specific power input per kg of black matter is preferably at least 50 kW/t (=50 J/(s*kg)=0.050 kW/kg), the specific power input L being calculated as follows $$\text{L}=\left(\text{P}\_\text{disagglomerate}\right)\text{/}\left(\text{m}\_\text{black mass}\right)$$

where P_Desagglo is the power consumption of the desagglomeration unit and m_Schwarzmasse is the mass of the black mass.

This selective, non-thermal deagglomeration of the black mass enables the clean separation of the so-called black mass (separated coating of the battery electrodes, which contains valuable preliminary products or raw materials) from the remaining battery components. Fine to ultra-fine screening requires a deagglomerated black mass to separate small metal parts (Cu, Al, Fe). The smaller the average particle size of the black mass or the median value (x ₅₀ ) of the particle size distribution of the black mass, the finer it can be sieved with high yields and high purity and the more small metal parts can be separated from the desired black mass by screening.

In addition, the subsequent separation of the graphite through sifting, flotation and/or heavy liquids is made possible by the deagglomeration. At the same time, this separation is the prerequisite for efficient metallurgical processing, since higher concentrations of the valuable metals nickel and cobalt result in better plant utilization. And also for the recovery of the graphite at a high value-added level, preferably as battery graphite in very high purity.

5. Electrolyte removal and drying of residual water - Step 20:

Beginning with the comminution or immediately after the comminution, the electrolyte content of the electrochemically inactive or inactivated cell components is rapidly reduced in order to prevent the formation of an ignitable or explosive mixture during subsequent further processing or in the storage and shipping packaging. This means that there is no longer any risk of fire or explosion from the resulting components.

Electrolyte removal is preferably functionally integrated with deagglomeration and carried out in parallel in the same apparatus.

Drying out from the wet comminution or other moisture introduced is particularly preferred.

1. a) Vakuumtrocknung - Schritt 22 - mit einer Temperatur unter 80°C zur Minimierung der HF-Bildung oder unter erhöhter Temperatur von über 80 °C in Kombination mit einer Gaswäsche der Abgase; das Vakuum wird hierbei vorzugsweise durch eine trockenlaufende Vakuumpumpe zur Verfügung gestellt, jedoch ist auch die Nutzung anderer Bauarten von Vakuumpumpen möglich;
2. b) Kontakttrocknung - Schritt 24 - und zwar kontinuierlich durch Kontakt zu einem Drehrohr mit einer Temperatur über 120 °C, vorzugsweise in einem in Batchweise befüllten, beheizten Behälter, in welchem eine Durchmischung durch Drehung oder Mischwerkzeuge gewährleistet wird; die Kontakttrocknung kann dabei mit einer Vakuumtrocknung kombiniert werden;
3. c) Konvektionstrocknung - Schritt 26 - mit Inertgas oder vorzugsweise vorgetrockneter Umgebungsluft in derartigem Überschuss, dass kein explosionsfähiges Gemisch entstehen kann;
4. d) Strahlungstrocknung - Schritt 28 - und zwar durch Infrarot-Strahlung und/oder UV-Strahlung und/oder Mikrowellenstrahlung; die Strahlungstrocknung kann mit der Vakuumtrocknung und der Kontakttrocknung kombiniert werden;
5. e) oder eine Kombination dieser Trocknungs-Arten 22, 24, 26, 28.

This targeted removal of the electrolyte takes place, for example

1. a) vacuum drying - step 22 - at a temperature below 80°C to minimize HF formation or at an elevated temperature of above 80°C in combination with a gas scrubbing of the exhaust gases; the vacuum is preferably provided by a dry-running vacuum pump, but the use of other types of vacuum pumps is also possible;
2. b) contact drying—step 24—continuously through contact with a rotary tube at a temperature above 120° C., preferably in a heated container filled in batches, in which thorough mixing is ensured by rotation or mixing tools; contact drying can be combined with vacuum drying;
3. c) convection drying - step 26 - with inert gas or preferably pre-dried ambient air in such an excess that no explosive mixture can form;
4. d) radiation drying - step 28 - by infrared radiation and/or UV radiation and/or microwave radiation; radiation drying can be combined with vacuum drying and contact drying;
5. e) or a combination of these drying types 22, 24, 26, 28.

In one embodiment, drying takes place in functional integration with thermal decomposition of the binder at a temperature of 450-1000° C. as preparation for simple separation of the electrode coating.

Optionally, a re-condensation—step 29—of the electrolyte solvent takes place.

In addition, optional (preferably removable) reagents for fluorine depletion/reaction (e.g. limestone granules) are used.

Preferably, in the area in which the drying process is carried out, the flow cross-section, preferably up to the dedusting unit into which the drying gas is discharged, is selected so large that the flow speed is on average below 5 m/s in order to avoid contamination and components of the dedusting unit, such as filters.

Preferably, the electrolyte recovery process is at least partially carried out in a long-term mobile drying vessel. This drying container is filled directly from a comminution unit or from the deagglomeration device and evacuated together with them.

6. Gas cleaning - step 30 - in combination with solvent recovery - step 31:

1. a) Gaswäsche mit in einem vorzugsweise alkalischen Lösungsmittel (bspw. NaOH, KOH, Kalkmilch) zur Abbindung des resultierenden Fluorwasserstoffs, vorzugsweise durch einen Strahlwäscher, der auf der Saugseite ein Vakuum zur Verfügung stellt;
2. b) Adsorption der organischen Komponenten an Aktivkohle, optional gekoppelt mit Chemiesorption von Fluorwasserstoff;
3. c) Thermische Nachverbrennung;
4. d) Rekompression in Druckbehälter (z.B. Gasflaschen), Abtransport und zentrale Gasaufbereitung oder Gasverbrennung;
5. e) Kondensation - Schritt 29 - der organischen Komponenten (durch Abkühlen oder Ausfrieren) in Kombination mit der Rückgewinnung der Leichtsieder des Elektrolyten.

In order not to release the resulting drying gases, which may contain fluorine compounds, including hydrogen fluoride, and organic carbonates and their decomposition products, uncleaned into the environment, they are cleaned. This is preferably achieved through a combination of the following methods:

1. a) gas scrubbing in a preferably alkaline solvent (e.g. NaOH, KOH, milk of lime) to bind the resulting hydrogen fluoride, preferably using a jet scrubber which provides a vacuum on the suction side;
2. b) adsorption of the organic components on activated carbon, optionally coupled with chemisorption of hydrogen fluoride;
3. c) thermal post-combustion;
4. d) Recompression in pressure vessels (e.g. gas cylinders), removal and central gas processing or gas combustion;
5. e) Condensation - step 29 - of the organic components (by cooling or freezing) in combination with the recovery of the low boilers of the electrolyte.

7. Transport in gas-tight and dust-tight containers - Step 32:

The inactivated components obtained are preferably decanted as little as possible in order to avoid dust and gas exchange with the environment. The safest way of storing shredded batteries is to store them in a transport container that does not contain any oxygen or moisture and in which the shredded material cannot come into contact with moisture or atmospheric oxygen.

The dried battery materials are therefore preferably packaged in a dust-tight and gas-tight manner. This means that no carcinogenic components (e.g. cobalt and nickel oxides) and fluorine components that may be present can escape during subsequent transport and storage. In addition, the bulk material is protected from the influence of the surrounding atmosphere and the associated water ingress.

1. a) Vakuumverpackung;
2. b) Verpackung unter Inertgas;
3. c) einen gasdichten, vakuumfesten Behälter, der ein Vakuum hält und an den ein Austragsaggregat staubdicht angeschlossen werden kann;
4. d) einen gasdichten, vakuumfesten Behälter, der ein Vakuum hält und der ein Austragsaggregat aufweist, an welches ein anderer Behälter staubdicht angeschlossen werden kann;
5. e) einen Behälter, wie bspw. einen der oben beschriebenen Behälter, der ein Rühraggregat aufweist;
6. f) einen Behälter, wie bspw. einen der oben beschriebenen Behälter, der an eine Vakuumpumpe angeschlossen werden kann;
7. g) einen Behälter, wie bspw. einen der oben beschriebenen Behälter, in den eine Vakuumpumpe integriert ist;
8. h) einen Behälter, der eine Inertatmosphäre hält, insbesondere
   • - über Dichtigkeit und/oder
   • - über aktive sensorgesteuerte Inertisierung mit Inertgas, insbesondere druckgeregelt (vorzugsweise im Überdruck) oder sauerstoffgeregelt.

This happens, for example, through:

1. a) vacuum packaging;
2. b) packaging under inert gas;
3. c) a gas-tight, vacuum-tight container that maintains a vacuum and to which a discharge unit can be connected in a dust-tight manner;
4. d) a gas-tight, vacuum-tight container that maintains a vacuum and has a discharge unit to which another container can be connected in a dust-tight manner;
5. e) a container, such as one of the containers described above, which has a stirring unit;
6. f) a container, such as one of the containers described above, which can be connected to a vacuum pump;
7. g) a container, such as one of the containers described above, in which a vacuum pump is integrated;
8. h) a container holding an inert atmosphere, in particular
   • - about tightness and/or
   • - Via active sensor-controlled inerting with inert gas, in particular pressure-controlled (preferably in excess pressure) or oxygen-controlled.

In a preferred embodiment, the material to be comminuted can be dried convectively, thermally conductively or via a vacuum in the gas-tight transport container. This means that the drying time in the combined mixing and drying unit can be shorter. The heat can, for example, be introduced via a double jacket.

This transportable mixer, referred to here as transport mixer C, is preferably a mobile long-term dryer at the same time. It allows a long drying time.

It is advantageous because it has no limitation through diffusion, higher recycling efficiency through recovery of the organic carbonates and only low gas flows, so that it achieves efficient condensation through improved heat transfer and only low nitrogen consumption through carrier gas circulation.

It is also advantageous because it can be used to supply an enthalpy of vaporization over a long period of time and thus at a low temperature level.

It is preferably set up to use the waste heat from other units and processes.

The low temperature level enables a high coefficient of performance of a possible heat pump. Heat is preferably fed in from the discharge of the batteries or the deactivation step.

The low temperature level is advantageous because fewer unwanted side reactions occur due to the decomposition of conductive salt and organic carbonates and additives.

The transport mixer C thus represents a long-term mixer, which relieves the deagglomeration device over the drying time. The deagglomeration device only has to be operated until the desired deagglomeration is achieved. The remaining drying time until the drying criterion is reached takes place in the cheaper long-term dryer.

8. Emptying instead of further processing - step 34:

During transport and storage, the crushed battery material can compact into cohesive bulk material and subsequently form bulk material bridges, making defined, low-dust emptying difficult without human intervention. The transport mixer loosens the material and allows it to be conveyed and metered without contamination. In one embodiment, the transportable mixer contains a filling and dosing unit for safe, mobile emptying.

In the following, a module D preferably carries out the steps of heavy material separation, magnetic separation, non-ferrous metal separation, sieving, post-shredding and sifting for processing and separating the individual valuable material fractions.

After decentralized processing, the packaged product can be taken safely to a processing module with a larger capacity. However, this processing module can also be used decentrally to further separate the inactive battery fragments into the various material streams of aluminium, copper, separator and a powder fraction enriched with active materials/transition metals on site.

9. Heavy material separation - step 36:

Furthermore, a heavy material separation is preferably provided, which is carried out, for example, ferromagnetically and/or as a screening process.

10. Light fraction separation - Step 38:

Furthermore, a light fraction separation is preferably provided, which is carried out, for example, as a sifting, preferably combined with hard part separation.

11. Separation of the coating from current collector foils - step 40:

Furthermore, a separation of the coating of current collector foils is preferably provided, with the coating containing the active materials preferably being separated from the current collector foils, which contain aluminum and copper, for the purposeful processing of the active materials and the aluminum and copper.

Separation of the coating of the current collector foils preferably includes the steps of comminution, for example using a cutting mill, optionally combined with screening, the screening preferably being air-assisted, and screening off the already separated and deagglomerated coating.

12. Re-bottling and if necessary compacting - Step 42:

Furthermore, a renewed filling and, if necessary, compacting of the previously obtained substances is preferably provided.

13. Separation of Anodic Black Ground and Cathodic Black Ground - Step 44:

Furthermore, a separation of anodic black mass, in particular graphite, and cathodic black mass is preferably provided.

The aforementioned method steps 36, 38, 40 can also be carried out in reversed order.

Process steps 34, 36, 38 and 40 are preferably carried out in a dust-free environment. The sealing mechanisms that are common in conventional recycling machines are considered to be disadvantageous for the processing of lithium-ion batteries according to the invention, since harmful dusts could get into the environment. The invention therefore preferably provides that work is carried out in a dust-tight manner. Therefore, method steps 34, 36, 38 and 40 should preferably be carried out in a dust-tight and gas-tight manner. One embodiment provides for the use of closed air circuits.

In a preferred version, the processing module D can therefore be designed in such a way that it is operated in sub-areas under negative pressure, which prevents gas components from escaping from the system, and in sub-areas in overpressure only 10 ppm of the low boiler of the electrolyte is measured directly on the machine shell can become. This prevents the escape of hazardous battery components and hazardous reaction products from battery components.

The transport mixer C, which serves as a mobile long-term dryer and mixer, preferably comprises one or more interchangeable vacuum dryers. An increase in the drying capacity results from a preferred numbering-up of the transport mixers, in particular a parallel connection of several strands with such transport mixers C.

The transport mixer C enables dust-tight transport and automatic emptying of the cohesive bulk material. A mixing unit in the transport container avoids the risk of ver sealing due to its own weight and transport movements and thus a blockage of discharge points that is difficult to remove.

In a process provided according to an exemplary embodiment according to the invention at drying temperatures >80° C., the exhaust gases containing hydrogen fluoride or HF can be drawn off via a gas scrubber. However, in the warm intermediate product (among other things) further hydrogen fluoride (HF) is formed, which is preferably not released into the environment, in particular not in an uncontrolled manner. Provision is preferably made for the material not to come into contact with atmospheric moisture and oxygen when warm. Further reactions can be (largely) prevented in this way.

In the transport mixer C, the comminuted material can cool down and react to the end in a long-term dryer under vacuum - while it is connected to a gas scrubber. Advantageously, the decay process does not have to be temperature-limited for this purpose.

In the transport mixer C, reagents such as water, lime and/or milk of lime are preferably slowly mixed in to react off conductive salts such as lithium hexafluorophosphate (LiPF ₆ ) and potentially metallic lithium.

One embodiment provides that drying is carried out at higher temperatures, preferably 50° C. to 240° C., under vacuum with gas scrubbing and the material to be dried is then allowed to decay in the long-term dryer (connected to the same gas scrubber, if necessary).

A further embodiment provides that the binder is decomposed at higher temperatures, preferably 500° C. to 700° C., with gas scrubbing and then allowed to cool down in the long-term dryer.

A further embodiment provides that a decentralized electrolyte separation is carried out without gas scrubbing. This is preferably followed by central high-temperature drying in the same reactor or transport mixer C to remove high boilers and conductive salts at a temperature above 80° C. and preferably with central gas scrubbing.

The transport mixer C enables a significant reduction in the contamination of the environment with carcinogenic dusts by transporting a large volume and defined coupling mechanisms. For example, in a transport mixer, 5t, preferably 10t, particularly preferably 20t, can be filled, transported and emptied in a defined manner. In contrast, only 0.5-1 t of shredded battery material can be transported in a conventional BigBag as a transport container. The number of filling, loading and emptying processes with toxic materials can thus be carried out in a more defined manner and reduced by a factor of 40.

Overall, the invention improves the prior art, in which deagglomeration of active materials is achieved by thermal or chemical destruction of the binder. However, this thermal decomposition is energy-intensive and, among other things, exhaust gases containing fluorine are released, which have to be treated by gas scrubbing. Dissolution of the binder in conventional chemical processes is accompanied by the consumption of chemicals. Conventional, non-selective comminution processes, in which all the ground material is comminuted to the same limiting final grain size - e.g. defined by an outlet screen - lead to heating of the components whose comminution requires a higher input of energy. The high temperatures of these components, e.g. pieces of metal, can lead to damage when they are filled into plastic containers and toxic exhaust gases such as hydrogen fluoride can be released when they come into contact with binder and electrolyte components.

In addition, these conventional, non-selective comminution processes show a disadvantageous enrichment of sieve cuts <0.5 mm with electrode foil components, from which this fraction of the so-called black mass cannot be cleaned by classification.

In contrast, the present invention provides decentralized comminution of deactivated batteries in gas-tight comminuting machines with decentralized electrolyte separation. Advantageously, the resulting fractions are no longer easily flammable and can be transported safely with less effort and under fewer conditions. After the decentralized processing according to the invention, potentially hazardous waste is converted into several resource streams. These recyclable materials may be shipped across national borders and can be further processed particularly efficiently. The process is particularly advantageous and sensible from an economic and ecological point of view. In addition, oxidative processes can be prevented. The invention substantially reduces the risk of a deflagration and/or release of the solvent contained in batteries.

• Die Erfindung ermöglicht eine effiziente, reine und energiesparende Abtrennung der wertvollen Materialien, wie Kobalt, Nickel, Lithium und Graphit. Eine thermische Vorbehandlung der zu recycelnden Batterien wird vermieden. Eine Zerkleinerung der zu recycelnden Batterien unter Wasser wird vermieden. Die Erfindung erzielt eine hohe Ausbeute an Aktivmaterial. Das erfindungsgemäße Recyclingverfahren ist kostengünstig, sowohl bezogen auf Investitionskosten als auch auf laufende Kosten. Die Struktur des Aktivmaterials bleibt erhalten. Es erfolgt keine thermische Umwandlung des Aktivmaterials. Durch Aufbruch der Agglomerate wird eine saubere Abtrennung des Graphits von dem kathodischen Aktivmaterial, insbesondere Lithium-Metall-Oxid und Lithiumeisenphosphat, aus der Schwarzmasse ohne vorherige thermische Zersetzung des Binders vorbereitet. Graphit kann somit ökonomisch und ökologisch effizient zurückgewonnen werden. Ebenfalls kann Lithium - insbesondere ökonomisch und ökologisch effizient - zurückgewonnen werden. Aluminium aus Stromsammlerfolien und Batteriezellhüllen kann stofflich wiederverwertet werden. Die hohe Effizienz und hohe Rückgewinnungsraten bei niedrigem Energieverbrauch begründen eine signifikante CO₂-Einsparung.

Furthermore, thanks to the invention, the following advantages can be achieved:

• The invention enables the efficient, clean and energy-saving separation of valuable materials such as cobalt, nickel, lithium and graphite. A thermal pre-treatment of the recycling batteries is avoided. A crushing of the batteries to be recycled under water is avoided. The invention achieves a high yield of active material. The recycling process according to the invention is inexpensive, both in terms of investment costs and running costs. The structure of the active material is retained. There is no thermal conversion of the active material. By breaking up the agglomerates, clean separation of the graphite from the cathodic active material, in particular lithium metal oxide and lithium iron phosphate, from the black mass is prepared without prior thermal decomposition of the binder. Graphite can thus be recovered economically and ecologically efficiently. Lithium can also be recovered - particularly economically and ecologically efficiently. Aluminum from current collector foils and battery cell casings can be recycled. The high efficiency and high recovery rates with low energy consumption result in significant CO ₂ savings.

The recovered electrode coating powder mixture has a high specific surface and is therefore particularly reactive in subsequent hydrometallurgical recycling. The high purity of the resulting products leads to a high value of these products and enables a high selling price.

The invention avoids a wet intermediate and achieves a more separable intermediate than wet intermediates.

The invention can be used advantageously in the processing of scrap materials from battery electrode production, in the processing of scrap materials from battery cell production, in the processing of scrap materials from battery production, in the recycling of aged primary and secondary lithium batteries, e.g. from power tools, stationary energy storage, industrial storage and e-bikes.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 3289627 B1 [0025, 0026, 0028, 0034, 0036]
• EP 3312922 B1 [0029, 0031]
• DE 102012024876 A1 [0034, 0036]

Claims (23)

Recycling method for components of electrochemical energy stores, namely batteries with electrodes, which have electrode carrier foils and an electrode coating applied thereto, with the steps a) crushing (16) of battery material, such as production rejects resulting from the production of batteries, active and deactivated batteries or battery cells , in battery comminution, which comprises particles of the electrode carrier foils and particles of the electrode coatings, b) mechanical deagglomeration (18) of the particles of the electrode coatings contained in the battery comminution, characterized in that c) the step of mechanical deagglomeration (18) is carried out for such a long time and/or intensively until the maximum size of the particles of the electrode coatings no longer exceeds 100 µm in mass-related mean, and d) the electrode coatings are comminuted to such a particle size distribution that the mean diameter of the particles of the electrode coatings after mechanical deagglomeration is at most 1/10 of the mean size of the particles of the electrode carrier foils, based on the maximum Feret diameter of the particles of the electrode carrier foils. recycling process claim 1 , characterized in that the particle size distribution of the cathodic electrode coatings after the mechanical deagglomeration (18) has a median value x ₅₀ which is smaller than four times the median value x ₅₀ of the particle size distribution of the cathodic active material contained in the cathodic electrode coatings in an electrode to be recycled, preferably is less than 10 to 20 times the median value x ₅₀ of the particle size distribution of the cathodic active material contained in the cathodic electrode coatings in the electrode to be recycled in the recycling of lithium iron phosphate batteries. recycling process claim 1 or 2 , characterized in that the mechanical deagglomeration (18) is carried out with a specific power input by means of a deagglomeration device (B) for a period of at least one minute with at least 50 watts per kilogram of battery active materials contained in the crushed material. Recycling method according to one of the preceding claims, characterized by the further step, following the mechanical deagglomeration (18), of separating the particles of the electrode coatings from the dried material to be comminuted by sifting and/or screening. Recycling method according to one of the preceding claims, characterized by drying (20) or recovery of solvent contained in the electrolyte of the battery, preferably organic solvent, in a machine. recycling process claim 5 , characterized in that the drying (20) is used to also dry out coolants or extinguishing agents, for example water, of a wet crushing (16) preceding the drying (20). Recycling method according to one of the preceding claims, characterized in that the steps of crushing (16) and drying (20) are combined and carried out in an explosion-proof manner in a drying room of the machine in which negative pressure or vacuum prevails, with explosion protection by monitoring the pressure takes place in this drying room and preferably the pressure resistance of the machine is determined in such a way that in the event of an explosion the pressure increase in the machine leads to the maximum forces acting on the machine that can be tolerated by the machine, in particular that the operating pressure in this drying room is in the range of one twentieth to one fifth of the compressive strength of the machine. Recycling method according to one of the preceding claims, characterized in that the duration of the drying (20) is determined during operation as a function of a combination of measured values for the proportion of volatile organic carbon in the drying gas and the absolute pressure and/or the rate of change in the absult pressure in the drying space and is regulated. Recycling method according to one of the preceding claims, characterized in that the galvanic elements of the batteries are deactivated by deep electrical discharge before the comminution. Recycling method according to one of the preceding claims, characterized in that the materials to be recycled are components of batteries which were once electrically charged and were then deactivated, the deactivation being effected by a) deep discharge and/or b) removal of the electrolyte by vacuum drying, preferably at a pressure of 0 to 600 mbar, preferably at temperatures <80°C and/or c) thermal removal of the electrolyte at temperatures >80°C and/or d) comminution in aqueous solution and /or e) crushing into coolant/extinguishing agent and/or f) crushing/mixing with a binding agent, e.g. lime, milk of lime. Recycling method according to one of the preceding claims, characterized in that the materials to be recycled are production rejects from electrode production for lithium-ion batteries or from lithium-ion battery production, preferably from lithium-ion batteries which have never been electrically charged. Recycling method according to one of the preceding claims, characterized in that the batteries have composite materials of electrode assemblies including electrode carrier foils with electrode coatings and separator foils applied thereto. Recycling method according to one of the preceding claims, characterized in that after the comminution, the battery comminuted material is stored and transported in a gas-tight and dust-tight transportable transport mixer (C), the transport mixer (C) having: a) a mixing tool for mechanical mixing and loosening up the battery comminuted material, b) a connection option for an active discharge aid or a permanently installed active discharge aid or a conveyor unit for discharging the battery comminuted material and c) means for inerting and/or evacuating the transport mixer (C) and repeatably in the battery comminuted material Filled state of the transport mixer (C) without dust to the transport mixer (C) to abandon gas, from the transport mixer (C) vent gas and / or in the transport mixer (C) to create a vacuum. recycling process Claim 13 , characterized in that in the transport mixer (C) the battery shredding material is dried for a long time, for example over a period of more than 30 minutes, with a) the long-term drying before the deagglomeration or b) the deagglomeration before the long-term drying or c) the deagglomeration and the long-term drying be carried out simultaneously. Recycling method according to one of Claims 13 or 14 , characterized in that drying heat is introduced into the transport mixer (C), e.g. by introducing a temperature control liquid into a double jacket surrounding the drying space to control the temperature of the walls of the drying space and/or by heating a heating jacket surrounding the drying space. recycling process claim 15 , characterized in that the drying heat is preferably supplied over a longer period of time, for example more than 30 minutes, and at a low temperature level, for example at a temperature below 100° C., preferably below 80° C. and particularly preferably below 60° C the drying heat is supplied by using a heat pump and/or using waste heat from other aggregates and processes than the aggregates and processes used in the recycling process. Recycling method according to one of Claims 13 until 16 , characterized in that after the steps of comminution and intensive mixing, the transport mixer (C) is used for post-drying. Recycling method according to one of Claims 13 until 17 , characterized in that the transport mixer (C) is connected to a drying system. Recycling method according to one of Claims 13 until 18 , characterized in that the transport mixer (C) is connected via a feed system for feeding in the battery material or via a gas pipe connection to a drying and condensation circuit of a preparation plant for crushing the battery material and for electrolyte recovery. Recycling method according to one of Claims 13 until 19 , characterized in that the transport mixer (C) is protected against an explosion by means of an explosion protection device, the explosion protection device a) a device for monitoring the pressure in the drying chamber, b) a device for monitoring volatile organic carbons in the drying gas, and/ or c) has a device for monitoring the oxygen in the drying gas and/or drying room. Recycling method according to one of Claims 13 until 20 , characterized in that in the transport mixer (C) the battery crushed material on roads, rails and / or ships transported to a treatment site and connected there to a treatment plant, in particular to a drying system of the treatment plant, and/or emptied into this treatment plant. Recycling device that is set up for recycling components of electrochemical energy stores, namely batteries with electrodes that have electrode carrier foils and an electrode coating applied thereto, with a) a shredding unit (A) for shredding (16) deactivated or non-electrochemically active battery material, such as e.g. in the production of batteries, production waste, deactivated batteries or battery cells, in battery comminuted material, which comprises particles of the electrode carrier foils and particles of the electrode coatings, b) a deagglomeration device (B) for mechanical deagglomeration (18) of the electrode coating particles contained in the battery comminuted material, thereby characterized in that c) the deagglomeration device (B) has a control device which is designed in such a way to carry out the mechanical deagglomeration (18) long and/or intensively until the maximum size of the particles of the electrode coatings no longer exceeds 100 µm in the mass-related mean and the electrode coatings are comminuted to such a particle size distribution that the mean diameter of the particles of the electrode coatings after the mechanical deagglomeration (18) is at most 1/10 of the mean size of the particles of the electrode carrier foils, based on the maximum Feret diameter of the particles of the electrode carrier foils, amounts. recycling facility Claim 22 characterized by a gas-tight and dust-tight transportable transport mixer (C) for storing and transporting the battery comminuted material, the transport mixer (C) having: a) a mixing tool for mechanically mixing and loosening the battery comminuted material, b) a connection option for an active discharge aid or a permanently installed active discharge aid for discharging the battery comminuted material and c) means for rendering the transport mixer (C) inert and for evacuating it and for repeatably feeding gas to the transport mixer (C) when it is filled with battery comminuted material without the formation of dust, vent gas from the transport mixer and apply vacuum in the transport mixer.

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