Method, drying device, battery recycling system and control and / or regulating unit

Abstract

A method for drying at least one battery material with a drying device (10), in particular an industrial drying device (12), comprising at least the following steps is described: Drying (100) of the battery material in a low temperature and / or low pressure range, wherein in at least one drying step (120) low-boiling substances are removed from the battery material, wherein in at least one further drying step (122) high-boiling substances are removed from the battery material, proposed.

Description

State of the art

[0001] The invention relates to a method for drying at least one battery material according to claim 1, a drying device according to claim 9, a battery recycling system according to claim 12 and a control and / or regulating unit according to claim 14.

[0002] A method for drying batteries has already been proposed in EP 3289627 B1, in which both the low-boiling and high-boiling components are removed in a drying step in the low-temperature and low-pressure range.

[0003] The object of the invention is, in particular, to provide a generic method with advantageous properties with regard to drying efficiency. This object is achieved according to the invention by the features of claim 1, while advantageous embodiments and further developments of the invention can be found in the dependent claims. Advantages of the invention

[0004] A method for drying at least one battery material using a drying device, in particular an industrial drying device, is described, comprising at least the following steps: Drying the battery material in a low temperature and / or low pressure range, wherein, in at least one drying step, low-boiling substances are removed from the battery material, It is proposed that at least one further drying step should remove high-boiling substances from the battery material.

[0005] Such a process can advantageously increase drying efficiency, as optimal drying conditions for low-boiling and high-boiling substances can be provided in each drying step. This allows for a reduction in drying time. Particularly advantageous is the further improvement of the cost-effectiveness of drying battery materials. Furthermore, the scalability of the drying process, especially in industrial applications, can be improved by separating the drying steps for low-boiling and high-boiling substances. Additionally, drying in the low-temperature and / or low-pressure range can advantageously improve the durability of the drying equipment and, in particular, a battery recycling system, by largely preventing the formation of hazardous substances during drying, especially hydrogen fluoride.Furthermore, drying can advantageously remove so much electrolyte from the battery material that an electrochemical reaction is no longer possible or only possible to a negligible extent.

[0006] The process is specifically for drying battery material for recycling batteries, particularly accumulators. Specifically, the battery material is a battery and / or at least a part of a battery, particularly an accumulator and / or a part of an accumulator, which is used in particular in the manufacture or assembly of batteries, preferably including the parts and materials that arise as rejects during the manufacturing process. Furthermore, the term "battery material" includes all material resulting from the recycling process, in particular the material produced by crushing batteries. "At least one" battery material is understood to mean, in particular, the material of at least one battery, or preferably, the material of a plurality of batteries.Preferably, the process for drying battery material consists of all batteries suitable for recycling and / or inactivation, such as lead-acid batteries, nickel-cadmium batteries, nickel-metal hydride batteries, sodium-ion batteries and / or, particularly preferably, lithium-ion batteries.

[0007] The drying step for drying the low-boiling components and the drying step for drying the high-boiling components are carried out using the drying device, for example by vacuum drying, contact drying, convection drying, and / or radiation drying. The drying device includes a drying chamber into which the battery material is introduced for drying. Preferably, the drying chamber is hermetically sealed, at least for the drying of the battery material. The term "industrial drying device" is understood to mean, in particular, that the drying device is specifically designed for large-scale use in industrial processes. Specifically, the drying chamber has a capacity of at least 50 liters, preferably at least 200 liters, advantageously at least 1000 liters, particularly preferably at least 10,000 liters, and most advantageously at least 20,000 liters.

[0008] Preferably, drying is carried out under stirring and / or mixing, wherein the drying device has at least one agitator, in particular for mixing and / or granulating the battery material at least in the drying container, with at least one agitator with agitator blades, in particular at least two agitator blades, which are preferably connected to a motor-driven shaft, and the agitator blades, which are in particular flat, are arranged inclined upwards from the inside to the outside at an angle α, which is preferably in a range of about 15° to about 60°, wherein in particular at least one of the agitator blades is equipped at its inner end with a bottom blade forming a bottom scraper.Preferably, the drying vessel consists of an upper cylindrical part and an adjoining lower conical bottom part, the angle of which is particularly in the range of about 60° to about 120° and preferably substantially 90°. Preferably, the stirring blades are arranged at least substantially within the conical part of the drying vessel. In particular, the battery material is stirred by the stirring blades in the conical part of the drying vessel. This advantageously further improves the drying of the battery material.

[0009] In particular, the set temperature and / or pressure in the drying device, especially in the drying vessel, define drying parameters for removing the low-boiling and / or high-boiling elements. Specifically, in the drying step for removing the low-boiling elements and / or the drying step for removing the high-boiling elements, water is removed from the battery material. Preferably, the drying takes place in a low-temperature range at a temperature below the boiling point under standard conditions of at least one low-boiling element and / or one high-boiling element, preferably at least to a substantial extent below 200 °C, advantageously at least to a substantial extent below 150 °C, and particularly preferably at least to a substantial extent below 120 °C. In particular, a low-pressure range is understood to mean a controlled vacuum.Preferably, drying takes place in the low-pressure range at a pressure below the vapor pressure of at least one low-boiling and / or high-boiling substance at the set temperature. In particular, a pressure of at least a substantial portion of a maximum of 500 hPa, preferably at least a substantial portion of at most 400 hPa, and most preferably at least a substantial portion of at most 350 hPa is used for drying in the low-temperature range.The term "at least to a substantial extent" shall be understood in particular to mean that at least 20%, preferably at least 50%, advantageously at least 75%, and particularly preferably at least 90% of the drying step and / or process step are carried out with the corresponding parameters, wherein in particular the further proportion also includes a fall below and / or an exceedance of the value, and particularly advantageously the entire drying step and / or process step is carried out with the corresponding parameters.

[0010] In particular, during drying, the electrolyte content, especially the proportion of electrolyte solvent, in the battery material is reduced, and the battery material is inactivated, preferably until an electrochemical reaction is impossible. Preferably, after drying, the electrolyte content is below a threshold value, in particular at which the cell voltage has decreased to at most one-third, preferably to one-quarter. Preferably, the drying of the comminuted material is stopped when, after completion of the drying process, no flammable or explosive gas mixture can form above the battery material and / or when the battery material is so dry that it is at least substantially inert, in particular so that no flammable or explosive gas mixture can form during further processing.Preferably, the drying, in particular the drying steps for removing the low and high boiling points, is carried out until the electrolyte content is at most 6 wt.%, preferably at most 4 wt.%, advantageously at most 3 wt.% and particularly preferably at most 2 wt.%.

[0011] Preferably, during the drying step to remove the low-boiling components, the portions of the battery material containing easily volatile components, which have a boiling point below 150 °C, particularly under standard conditions, are removed, wherein preferably the proportion of the low-boiling components remaining after the drying step is at most 6 vol%, more preferably at most 4 vol%, and most preferably at most 3 vol%. Low-boiling components, particularly in lithium-ion batteries, are, for example, solvents such as dimethyl carbonate (DMC) and / or ethyl methyl carbonate (EMC).

[0012] Preferably, during the drying step to remove high-boiling components, the portions of the battery material containing components that are difficult to vaporize and which, particularly under standard conditions, have a boiling point above 150 °C, are removed. Preferably, the proportion of high-boiling components remaining after the drying step is at most 6 vol%, more preferably at most 3 vol%, advantageously at most 1 vol%, and most preferably at most 0.5 vol%. Examples of high-boiling components are organic electrolytes such as ethylene carbonate (EC) and / or propylene carbonate (PC), and / or additives such as cyclohexylbenzene and / or various flame retardants.

[0013] Preferably, the drying step for removing the low-boiling components is carried out, in particular immediately, before the drying step for removing the high-boiling components, and preferably after the drying step for removing the low-boiling components has been completed. In particular, the drying step for removing the low-boiling components and / or high-boiling components is carried out under drying parameters that are specifically adjusted to remove the low-boiling components and / or high-boiling components. In particular, the drying parameters are adjusted during the transition from the drying step for removing the low-boiling components to the drying step for removing the high-boiling components.

[0014] Alternatively, it is conceivable that the drying step for removing the low-boiling substances overlaps at least partially with the drying step for removing the high-boiling substances, wherein, in particular, at most 80%, preferably at most 50%, and most preferably at most 20% of the drying step for removing the low-boiling substances overlaps with the drying step for removing the high-boiling substances, and / or, in particular, at most 80%, preferably at most 50%, and most preferably at most 20% of the drying step for removing the high-boiling substances overlaps with the drying step for removing the low-boiling substances. Preferably, during the overlap of the drying steps for removing the low-boiling substances and for removing the high-boiling substances, drying parameters, in particular a low-temperature range and / or a low-pressure range, are set under which the removal of the low-boiling substances and the high-boiling substances takes place.

[0015] Preferably, in at least one further process step, the battery material is comminuted, preferably providing the comminuted material to separate, for example, cathode and anode materials, separators, and electrolytes. In principle, it is conceivable that the comminution step of the battery material takes place after drying the battery material. Particularly preferably, the comminution step of the battery material takes place, preferably immediately, before drying the battery material. Preferably, the comminution in this process step is carried out using shear, impact, and collision forces to ensure efficient separation of the materials and to prepare the comminuted material for subsequent sieving.Preferably, the shredded battery material is passed through at least one sieve, and in particular several sieves with different mesh sizes, of the shredding device, which is preferably arranged below a shredding shaft of the shredding device. The sieve is preferably provided for this purpose.

[0016] Preferably, in a further process step, advantageously after drying the battery material in a low-temperature and / or low-pressure environment, high-temperature drying is carried out. In particular, the high-temperature drying is intended to decompose a binder, for example, consisting of polyvinylidene fluoride, polytetrafluoroethylene, carboxymethylcellulose, styrene-butadiene rubber, and / or another material suitable for the respective battery material. Preferably, the high-temperature drying is carried out at a drying temperature and for a drying duration selected such that the binder, which binds the active material of the lithium battery to a support, decomposes at least predominantly.The decomposition temperature is understood in particular to be the lowest temperature at which, after holding the battery material at this temperature for one hour, at least 80 percent by mass of the binder has decomposed into gaseous components, in particular at least to a substantial extent at a temperature of at least 200 °C, preferably at least to a substantial extent at a temperature between 200°C and 500°C.

[0017] Furthermore, it is proposed that the drying step for removing the low-boiling elements and the drying step for removing the high-boiling elements be carried out in a single drying chamber of the drying device and / or in batch operation. This advantageously allows for precise control of the drying parameters for each batch of battery material, resulting in a more uniform and reliable removal of low-boiling and high-boiling elements. Costs can also be reduced, as maintenance is advantageously simpler and energy consumption is lowered. Specifically, a single drying chamber is understood to be a drying space bounded by an outer wall, which may, in particular, have several drying chambers; however, preferably the drying chamber has only one receiving chamber for drying the battery material.The battery material is preferably fed from a bunker into the drying device, with the battery material for batch operation being advantageously stored in the bunker.

[0018] In an alternative embodiment of the invention, drying takes place in at least two drying containers of the drying device and / or in continuous operation. In particular, the removal of the low-boiling components is carried out in at least a first drying container or in a first part of the drying container, and the removal of the high-boiling components is carried out in at least a second drying container or in a second part of the drying container. In particular, the battery material is continuously fed to and removed from the drying device. In continuous operation, with only one drying container, the battery material is continuously passed through several drying chambers within the drying container.

[0019] It is further proposed that the drying step for removing the high-boiling components be carried out at a higher temperature than the drying step for removing the low-boiling components. By adjusting the drying temperatures to the specific boiling points of the low-boiling and high-boiling components, a more precise and effective removal of the various components can advantageously be achieved. In particular, the formation of hydrogen fluoride can be advantageously prevented, at least substantially, and the high-boiling components can be removed as efficiently as possible. Specifically, the temperature is increased from the drying step for removing the low-boiling components to the drying step for removing the high-boiling components. Preferably, the transition between the drying step for removing the low-boiling components and the drying step for removing the high-boiling components is achieved by controlled self-heating of the battery material.Preferably, after the drying step to remove the low-boiling substances, further thermal energy is supplied, which is set to evaporate the low-boiling substances, so that, in particular due to the higher boiling point of the high-boiling substances, the battery material heats up further, preferably until the high-boiling substances evaporate at these higher temperatures.

[0020] Alternatively, the temperature, and in particular the supply of thermal energy, is actively controlled, especially during the transition between the drying step for removing the low-boiling components and the drying step for removing the high-boiling components. This could be done, for example, to accelerate the heating of the battery material to the temperature required for removing the high-boiling components. In particular, it is conceivable that the temperature, and especially the supply of thermal energy, is increased prematurely. This can advantageously accelerate the drying process. Alternatively, it is conceivable that the supply of thermal energy is initially reduced after the drying step for removing the low-boiling components, so that the temperature in the drying step for removing the high-boiling components is initially constant compared to the temperature in the drying step for removing the low-boiling components.This allows for a further advantageous reduction in the proportion of low-boiling substances and the water content of the battery material, while also ensuring that the formation of hydrogen fluoride during heating is prevented. Premature or delayed heating leads to an overlap of the drying steps required to remove the low-boiling and high-boiling substances.

[0021] Furthermore, it is proposed that in the drying step for removing the high-boiling components, the drying process be carried out at least to a substantial extent at a temperature of at least 80 °C. This advantageously ensures that the high-boiling components evaporate efficiently. Moreover, the two separate drying stages can advantageously reduce the required vacuum level in industrial dryers with numerous sealing points and openings, as the temperature, particularly for the high-boiling components, is adjusted. Specifically, the removal of the high-boiling components is carried out at a temperature at least to a substantial extent between 80 °C and 150 °C, preferably at least to a substantial extent between 80 °C and 120 °C, and most preferably at least to a substantial extent between 80 °C and 110 °C.Furthermore, investigations have shown that a temperature range between 100 °C and 120 °C is advantageous for removing the high-boiling components, at least to a significant extent. Preferably, the battery material is dried in the drying step for removing the high-boiling components at least approximately and to a significant extent at a constant temperature profile, in particular at a constant temperature of at least 80 °C. An at least approximately constant temperature profile is understood to mean, in particular, a deviation, in particular a temperature fluctuation, of at most 20%, preferably 10%, advantageously 5%, and most preferably 1%. In a further embodiment of the invention, the battery material is dried in the drying step for removing the high-boiling components using a multi-stage temperature profile, wherein, in particular, different temperatures are set for different high-boiling components.

[0022] Furthermore, it is proposed that in the drying step for removing the low-boiling components, the drying process be carried out at least to a substantial extent at a temperature of no more than 80 °C. This advantageously minimizes the risk of the formation of hazardous gases, particularly hydrogen fluoride, which arises especially when fluorine-containing compounds decompose at higher temperatures. Preferably, in the drying step for removing the low-boiling components, the battery material is dried at least approximately and to a substantial extent at a constant temperature profile, particularly at a constant temperature of no more than 80 °C. In a further embodiment of the invention, the battery material is dried in the drying step for removing the low-boiling components using a multi-stage temperature profile, with different temperatures being set for different high-boiling components.

[0023] Furthermore, it is proposed that the pressure in the drying step for removing the high-boiling substances be set lower than in the drying step for removing the low-boiling substances. This advantageously lowers the evaporation temperature of the high-boiling substances, thus increasing the efficiency of the drying process. Furthermore, the formation of undesirable byproducts such as hydrogen fluoride can be advantageously avoided, at least substantially, during the removal of the high-boiling substances. In particular, the pressure is reduced from the drying step for removing the low-boiling substances to the drying step for removing the high-boiling substances. Specifically, in the drying step for removing the low-boiling substances, drying takes place at least to a substantial extent at a pressure of at least 100 hPa, preferably at least 200 hPa, advantageously at least 250 hPa, and particularly preferably at least 300 hPa.In particular, during the drying step for removing the high-boiling components, drying is carried out, at least to a substantial extent, at a pressure of no more than 300 hPa, preferably no more than 250 hPa, advantageously no more than 200 hPa, particularly preferably no more than 100 hPa, and most advantageously no more than 50 hPa. Preferably, the pressure is adjusted using a vacuum unit.

[0024] Furthermore, it is proposed that a fluid generated during the drying step for removing low-boiling substances and / or during the drying step for removing high-boiling substances be purified by a cleaning unit, particularly to remove at least hydrogen fluoride. This advantageously allows for more flexible temperature and / or pressure adjustment, as the release of hazardous substances such as hydrogen fluoride into other system components or the environment is at least substantially prevented. Specifically, the fluid, particularly the exhaust gas from the drying process, is purified by the cleaning unit located between the drying vessel and the vacuum unit.Preferably, the fluid is purified by a purification unit designed as a filter, in particular an activated carbon filter and / or a filter containing substances that react with hydrogen fluoride, and / or a purification unit designed as a gas scrubber, wherein the hydrogen fluoride is preferably absorbed from the fluid into a scrubbing liquid. In particular, the purification unit designed as a gas scrubber can advantageously prevent the release of hydrogen fluoride to a large extent, even when larger quantities are generated.

[0025] Furthermore, it is proposed that after at least one drying cycle, the drying container can be cleaned and / or maintained by opening a sealing unit of at least one drying container. This advantageously allows for regular cleaning and maintenance of the drying container, which improves the efficiency and reliability of the drying process. Additionally, a lower vacuum can be advantageously applied in the drying container during the drying step for removing high-boiling components at temperatures above 80 °C, enabling the use of multiple sealing points in the drying device, particularly on the drying container. Specifically, a drying cycle includes at least the drying of the battery material in the low-temperature and / or low-pressure range.Preferably, the drying vessel is serviced and / or cleaned after a large number of drying cycles, in particular at least two, preferably at least five, advantageously at least 10, and particularly preferably at least 100. In particular, the closure unit is sealed with a gasket. Preferably, a pressure is set during the drying step to remove the high-boiling components, which is then sealed by the gasket. Preferably, the drying device, in particular the drying vessel, has further sealing points, such as an inlet and outlet opening for the battery material, safety valves and other valves, gas lines, purge lines, and a shaft access for the agitator.

[0026] Furthermore, a drying device, in particular an industrial drying device, for drying at least one battery material, in particular at least partially for carrying out the method, is proposed, comprising a vacuum unit and / or a heating unit, and a control and / or regulating unit, which is provided to regulate the vacuum unit and / or the heating unit in a low temperature range and / or low pressure range, wherein the control and / or regulating unit controls the vacuum unit and / or the heating unit in multiple stages during the drying of the battery material.

[0027] Such a drying device can advantageously increase drying efficiency in the drying of battery material, since the optimal drying conditions for individual components in the battery material, especially for the low-boiling and high-boiling components, can be provided in several stages.

[0028] Furthermore, the scalability of the drying process, particularly in industrial applications, can be advantageously improved due to the multiple stages. Additionally, drying in the low-temperature and / or low-pressure range can advantageously improve the durability of the drying device, particularly by preventing the formation of hazardous substances during drying, especially hydrogen fluoride. Specifically, the control unit is designed to control the heating unit and / or vacuum unit in multiple stages, depending on the components of the battery material to be removed. In particular, the control unit is designed to control at least two stages, specifically the drying stage for removing the low-boiling components and the drying stage for removing the high-boiling components.

[0029] Furthermore, it is proposed that the drying device comprise at least one drying container in which a pressure can be set by means of the vacuum unit. This pressure unit has at least one closure unit, which is designed to be opened, at least substantially, for cleaning and / or maintenance of the drying container. This advantageously allows for regular cleaning and maintenance of the drying container, which in particular increases the efficiency and reliability of the drying process. Specifically, the closure unit is sealed by means of a gasket. Preferably, the heating unit is provided for setting a temperature in the drying container and / or the vacuum unit is provided for setting a pressure in the drying container.

[0030] Furthermore, it is proposed that the dryer device includes at least one sensor unit designed to detect at least one drying parameter, in particular temperature, humidity, and / or gas composition, in the drying vessel, with the control unit performing multi-stage control based on the drying parameters. This advantageously provides optimized control of the drying parameters. In particular, the sensor unit is at least a temperature sensor element, a humidity sensor element, a pressure sensor element, and / or a gas composition sensor element. The sensor unit is especially preferably designed to detect at least one of the drying steps at the end, in particular the drying step for removing the low-boiling substances.Preferably, the sensor unit is designed to detect a temperature increase after the removal of the low-boiling substances, wherein the control and / or regulating unit controls at least the vacuum unit on the basis thereof, in particular the vacuum unit reduces a pressure in the drying container.

[0031] Furthermore, a battery recycling system is proposed, at least for carrying out the drying process of at least one type of battery material using a drying device. Such a battery recycling system can advantageously increase drying efficiency in the drying of battery material, as optimal drying conditions for the low-boiling and high-boiling components can be advantageously provided in separate drying steps. Moreover, the separation of the drying steps for low-boiling and high-boiling components can advantageously improve the scalability of the drying process and the battery recycling system, particularly in industrial applications.Furthermore, drying in the low-temperature and / or low-pressure range can advantageously improve the durability of the battery recycling system, particularly by preventing the formation of hazardous substances during drying, especially hydrogen fluoride. Specifically, the battery recycling system is a specialized facility for the environmentally sound and efficient recovery of valuable materials from used batteries and / or materials generated as waste during the battery manufacturing process, especially from lithium-ion batteries.

[0032] Furthermore, it is proposed that the battery recycling system includes a shredding unit designed to provide shredded battery material, with a drying unit designed to dry the shredded material. This advantageously ensures more efficient and uniform drying of the battery material. In particular, the shredding unit is designed to shred the battery material, especially subunits such as modules and / or stacks, and / or cells, for example, by means of at least one rotary shear, at least one rotor, and / or at least one cutting mill, preferably under a protective gas atmosphere.

[0033] Furthermore, the control unit for carrying out the drying process of the at least one battery material is proposed to be integrated with the drying device, in particular at least partially with the drying device. The phrase "at least partially attributable to the drying device" is understood to mean, in particular, that the control unit is implemented at least partially externally, specifically on a local computer in a local network of the drying device and / or on an external computer, in particular in the cloud. Alternatively, the drying device may fully encompass the control unit.

[0034] The inventive method for drying battery material, the drying device, the battery recycling system, and the control and / or regulating unit are not limited to the application and embodiment described above. In particular, the inventive method for drying battery material, the drying device, the battery recycling system, and the control and / or regulating unit may, to achieve a functionality described herein, comprise a different number of individual elements, components, and units than the number specified herein. Furthermore, when specifying a number of an element, component, or unit using the term "at least," the minimum number should also be explicitly disclosed, in particular by a limitation with "only." Drawings

[0035] Further advantages will become apparent from the following description of the drawings. The drawings illustrate an embodiment of the invention. The drawings, the description, and the claims contain numerous features in combination. A person skilled in the art will expediently consider the features individually and combine them into meaningful further combinations.

[0036] They show: Fig. 1 a schematic representation of a battery recycling system, at least with a drying device, Fig. 2 a schematic representation of the dryer device with at least one control and / or regulating unit for regulating at least one heating unit and / or vacuum unit, Fig. 3 a flowchart of a process for drying at least one battery material using the dryer device and Fig. 4 a schematic temperature and pressure profile during the drying of at least one battery material with the dryer device. Description of the exemplary embodiment

[0037] The Fig. Figure 1 schematically shows a battery recycling system 90 with a drying device 10. The battery recycling system 90 is designed to carry out at least one process for drying at least one type of battery material using the drying device 10. The battery recycling system 90 is designed for recovering valuable materials from used batteries. The battery recycling system 90 is designed for recovering valuable materials from parts that are generated as rejects during a battery manufacturing process. The battery recycling system 90 is designed for at least partial recycling of battery material. Preferably, the battery recycling system is designed for recycling lithium-ion batteries.

[0038] The battery recycling system 90 comprises at least one shredding device 14. The shredding device 14 is designed to provide the battery material for shredding. The shredding device 14 is designed to mechanically shred the battery material. The shredding device 14 is designed to shred the battery material using shear, impact, and / or collision forces. The shredded material is conveyed to the drying device 10. The battery recycling system 90 comprises a conveying system consisting of conveyor belts. The conveying system transports the shredded material from the shredding device 14 to the drying device 10. The drying device 10 is designed to dry the shredded material.

[0039] The battery recycling system 90 has a hopper (not shown) between the shredding device 14 and the drying device 10. The hopper collects the shredded material from the shredding device 14 before it reaches the drying device 10 to enable batch operation of the drying device 10.

[0040] The dryer 10 is an industrial dryer 12. The dryer 10 is specifically designed for large-scale use in industrial processes. The dryer 10 is designed as a vacuum dryer. The dryer 10 is intended for drying 100 of at least one battery material. The dryer 10 is at least partially intended for carrying out the process of drying the battery material.

[0041] The battery recycling system 90 includes at least one vacuum unit 20. The vacuum unit 20 is designed to remove the fluid produced during drying from the dryer 10. The vacuum unit 20 then passes the fluid produced during drying through a solvent recovery unit 16. The solvent recovery unit 16 is designed to adsorb the solvent dissolved in the fluid. The solvent recovery unit 16 includes distillation columns or condensers designed to condense the solvent. This recovery process allows the solvents to be regenerated and reused in the process, thus increasing the efficiency and sustainability of the battery recycling system 90.

[0042] The battery recycling system 90 has at least one recovery tank 22 for the solvent dissolved from the fluid produced during drying.

[0043] The battery recycling system 90 has at least one cleaning unit 18. The vacuum unit 20 guides the fluid produced during drying through the cleaning unit 18. The cleaning unit 18 is located downstream of the solvent recovery unit 16. The cleaning unit 18 is designed to remove hazardous substances from the fluid. The cleaning unit 18 is configured as a gas scrubber. The cleaning unit 18 is designed to remove hydrogen fluoride from the fluid produced during drying. The battery recycling system 90 has at least one outlet 24. The fluid produced during drying is discharged from the battery recycling system 90 through outlet 24 after the cleaning unit 18.

[0044] The battery recycling system 90 has at least one storage container 26 for storing the dried battery material. The storage container 26 for the dried battery material is located downstream of the drying device 10. The storage container 26 for the dried battery material is designed to receive the battery material after drying. The storage container 26 is, for example, designed as a container in which the battery material can be stored airtight.

[0045] The Fig. Figure 2 schematically shows the dryer 10. The dryer 10 includes the vacuum unit 20. The dryer 10 includes a heating unit 50. The dryer 10 includes a control unit 60. The control unit 60 is provided for carrying out the method of drying the at least one battery material with at least part of the dryer 10. The control unit 60 is provided for carrying out the method of drying the at least one battery material with the dryer 10. The control unit 60 is provided for controlling the vacuum unit 20 in a low-pressure range. The control unit 60 is provided for controlling the heating unit 50 in a low-temperature range. The control unit 60 controls the vacuum unit 20 in multiple stages during the drying process 100 of the battery material.The control unit 60 controls the heating unit 50 in multiple stages during the drying process 100 of the battery material. The control unit 60 controls the vacuum unit 20 at least to remove low-boiling substances from the battery material. The control unit 60 controls the vacuum unit 20 at least to remove high-boiling substances from the battery material. The control unit 60 controls the heating unit 50 at least to remove low-boiling substances from the battery material. The control unit 60 controls the heating unit 50 at least to remove high-boiling substances from the battery material.

[0046] The drying device 10 comprises at least one drying container 30. The drying container 30 is designed to hold the at least one battery material. The drying container 30 has a capacity of at least substantially between 50 l and 32,000 l. The battery material is fed in via a feed 28 from the comminution device 14. The drying container 30 has an inlet 70, which is designed for feeding the battery material into the drying container 30. The drying container 30 has at least one fluid valve 72, which is designed to release fluids generated during the drying process of the battery material from the drying container 30. The drying container 30 has at least one outlet 74, which is designed for discharging the dried battery material.

[0047] The dryer 10 has an agitator 42. The agitator 42 has a stirring element 44, which is designed to mix the battery material in the drying vessel 30. The agitator 42 has an agitator shaft 46 to which the stirring element 44 is attached. The agitator 42 has a drive unit 40, which is designed to drive at least the stirring element 44.

[0048] The drying container 30 has at least one sealing unit 80. The sealing unit 80 is designed to be at least substantially openable for cleaning and / or maintenance of the drying container 30. The drying container 30 is hermetically sealed for drying the battery material. The sealing unit 80 has a seal 82. The seal 82 seals the drying container 30 during the drying of the battery material. A temperature can be set in the drying container 30 by means of the heating unit 50. The heating unit 50 is designed to set a temperature in the drying container 30. A pressure can be set in the drying container 30 by means of the vacuum unit 20. The vacuum unit 20 is designed to set a pressure in the drying container 30.

[0049] The dryer 10 has at least one sensor unit 62. The sensor unit 62 is designed to detect at least one drying parameter. The control unit 60 performs the multi-stage control of the heating unit 50 based on the drying parameters detected by the sensor unit 62. The control unit 60 performs the multi-stage control of the vacuum unit 20 based on the drying parameters detected by the sensor unit 62. The sensor unit 62 is designed to detect at least one temperature in the drying container 30. The sensor unit 62 has at least one temperature sensor element. The sensor unit 62 is designed to detect the completion of the removal of the low-boiling substances. The sensor unit 62 is designed to detect a temperature increase after the removal of the low-boiling substances.The vacuum unit 20 reduces the pressure in the drying container 30 by means of a control unit 60 based on the temperature increase detected by the sensor unit 62.

[0050] The Fig. Figure 3 shows a flowchart of the process for drying the at least one battery material. The process is for drying the at least one battery material using the drying device 10. The process is for drying the at least one battery material using the industrial drying device 10.

[0051] In at least one process step, battery material is crushed 102. The crushing 102 of the battery material takes place in the crushing device 14. The crushed battery material is fed to the drying device 10.

[0052] In a further process step, the battery material is dried in a low-temperature environment. In this process step, the battery material is dried in a low-pressure environment. The drying of the battery material in the low-temperature and / or low-pressure environment comprises at least two drying steps.

[0053] In at least one drying step 120, the low-boiling elements are removed from the battery material. In at least one further drying step 122, the high-boiling elements are removed from the battery material.

[0054] Drying step 120 for removing the low-boiling components and drying step 122 for removing the high-boiling components are carried out in the individual drying vessel 30 of the dryer 10. These drying steps are performed in batch mode. The dryer 30 has a receiving chamber in which drying step 120 and drying step 122 are performed. Drying 100 is carried out with stirring and / or mixing, and the dryer 10 includes at least the agitator 42 for mixing the battery material, at least in the dryer 30.

[0055] Drying step 122 for removing the high-boiling substances takes place at a higher temperature 162 than drying step 120 for removing the low-boiling substances. In the Fig. Figure 4 shows a temperature profile 150 during the drying 100 of the battery material in the low-temperature and low-pressure range, plotted against a temperature axis 206 and a time axis 204. The temperature 160 from drying step 120 for removing the low-boiling elements is increased to drying step 122 for removing the high-boiling elements. After completion 200 of drying step 120 for removing the low-boiling elements, a transition to drying step 122 for removing the high-boiling elements occurs. A temperature profile 158 during the transition between drying step 120 for removing the low-boiling elements and drying step 122 for removing the low-boiling elements is achieved through controlled self-heating of the battery material. After completion 200 of drying step 120 for removing the low-boiling elements, further thermal energy is supplied, which is adjusted to remove the low-boiling elements.Due to the higher boiling point of the high-boiling elements at a set pressure of 180, the battery material heats up further until the high-boiling elements evaporate at the higher temperatures. The thermal energy is supplied by the heating unit 50. Once the high-boiling elements have been at least substantially removed from the battery material, the drying step 122 is completed.

[0056] In drying step 120 for the removal of the low-boiling elements, drying takes place at least to a significant extent at a temperature of 160, not exceeding 80 °C. The battery material is dried in drying step 120 for the removal of the low-boiling elements, at least approximately and to a significant extent, at a constant temperature profile 152, with a temperature of 160, not exceeding 80 °C. During a temperature start-up 156, the temperature of the drying device 10 for drying step 120 for the removal of the low-boiling elements is set. The battery material is fed into the drying container 30 after the temperature start-up 156. Alternatively, the battery material is fed into the drying container 30 either before or during the temperature start-up 156.

[0057] In drying step 122 for the removal of high-boiling components, drying takes place at least to a significant extent at a temperature of at least 80 °C (162). The removal of high-boiling components takes place at a temperature of at least between 80 °C and 110 °C (162). In drying step 122 for the removal of high-boiling components, the battery material is dried at least approximately and to a significant extent at a constant temperature profile (154) with a temperature of at least 80 °C (162).

[0058] The pressure 180 in drying step 122 for removing the high-boiling substances is set lower than in drying step 120 for removing the low-boiling substances. In the Fig.Figure 4 shows a pressure profile 170 during the drying 100 of the battery material in the low-temperature and low-pressure range, plotted against a pressure axis 208 and a time axis 204. A pressure 182 is reduced from drying step 120 (removing the low-boiling elements) to drying step 122 (removing the high-boiling elements). The pressure 180, 182 is set by the vacuum unit 20. A pressure profile 178 in a transition between drying step 120 (removing the low-boiling elements) and drying step 122 (removing the high-boiling elements) is achieved by lowering the pressure set in the drying vessel 30.

[0059] In drying step 120 for the removal of the low-boiling elements, drying takes place at least to a substantial extent at a pressure of at least 300 hPa. The battery material is dried in drying step 120 for the removal of the low-boiling elements at least approximately and to a substantial extent at a constant pressure profile 172 at a pressure of at least 300 hPa. During a pressure start 176, the pressure of the dryer device 10 for drying step 120 for the removal of the low-boiling elements is set. The pressure start 176 is simultaneous with the temperature start 156.

[0060] In drying step 122 for the removal of the high-boiling substances, drying takes place at least to a significant extent at pressure 180 of at most 300 hPa. In drying step 120 for the removal of the low-boiling substances, the battery material is dried at least approximately and at least to a significant extent at a constant pressure profile 174 with pressure 180 of at most 300 hPa.

[0061] In a further process step, solvent recovery 104 of the fluid produced during drying takes place. Solvent recovery 104 occurs during the drying 100 of the battery material. A fluid produced in the drying step 120 to remove the low-boiling substances is further processed in solvent recovery 104. A fluid produced in the drying step 122 to remove the high-boiling substances is further processed in solvent recovery 104. The evaporated solvents are condensed in solvent recovery 104 and collected in at least one recovery tank 22.

[0062] In a further process step, the fluid produced during drying 100 is purified. The fluid produced in drying step 120 to remove the low-boiling substances is purified by the purification unit 18. The low-boiling substances evaporated during drying step 120 are extracted from the dryer 10 and directed to the purification unit 18. The fluid produced in drying step 120 to remove the low-boiling substances is purified of hydrogen fluoride in the purification unit 18. The fluid produced in drying step 122 to remove the high-boiling substances is purified by the purification unit 18. The high-boiling substances evaporated during drying step 122 are extracted from the dryer 10 and directed to the purification unit 18. The fluid produced in drying step 122 to remove the high-boiling substances is purified of hydrogen fluoride in the purification unit 18.In a further process step, the purified fluid leaves the cleaning unit 18 at output 108 and is safely released into an environment.

[0063] The cleaning unit 18 functions as a gas scrubber, absorbing hydrogen fluoride in a scrubbing liquid. The contaminated fluid from the drying tank 30 enters the gas scrubber, where it passes through the scrubbing liquid and absorbs the pollutants, such as hydrogen fluoride. The scrubbing liquid is distributed within the gas scrubber via spray nozzles or packing material. The cleaned fluid exits the gas scrubber and is safely released into the environment. The scrubbing liquid is circulated by a pump and regenerated or replaced as needed. The loaded scrubbing liquid, containing the absorbed hydrogen fluoride, is collected and treated. This treatment step involves removing the absorbed pollutants to prepare the scrubbing liquid for reuse.

[0064] In a further process step, the dried battery material is stored. The dried battery material is stored in at least one storage container. After storage, the dried battery material undergoes further processing. Alternatively, the dried battery material is processed directly after drying. The dried battery material is conveyed on a conveyor belt to a further processing plant.

[0065] After at least one drying cycle 220, the drying container 30 is cleaned and / or serviced by opening the closure unit 80. The drying cycle 220 includes at least the drying 100 of the battery material in the low-temperature and low-pressure range. The cleaning and / or service of the drying container 30 is performed after a number of drying cycles 220. The closure unit 80 is sealed with the gasket 82 during the drying 100 of the battery material in the low-temperature and low-pressure range. In the drying step 120 for removing the low-boiling elements, the pressure 102 is set, which is sealed with the gasket 82. In the drying step 122 for removing the high-boiling elements, the pressure 180 is set, which is sealed with the gasket 82. Reference sign 10 Dryer device 12 Industrial drying device 14. Shredding device 16 Solvent recovery 18 cleaning units 20 vacuum units 22 Recovery tank 24th issue 26 storage containers 28 Supply 30 drying containers 40 drive unit 42 Agitator 44 Stirring element 46 Stirrer shaft 50 heating units 60 Control and / or regulating unit 62 sensor units 70 admission 72 Fluid valve 74 Outlet 80 locking unit 82 Mechanical seal 90 Battery recycling system 100 Drying 102 Crush 104 Solvent recovery 106 Cleaning Issue 108 110 Storage 112 Further processing 114 Storage 120 drying step 122 Drying step 150 Temperature profile 152 Temperature profile 154 Temperature profile 156 Temperature start-up 158 Temperature profile 160 temperature 162 Temperature 170 Pressure profile 172 Pressure profile 174 Pressure profile 176 Print start 178 Pressure profile 180 Print 182 Print 200 Graduation 202 Conclusion 204 Timeline 206 Temperature axis 208 Pressure axis 220 drying cycles QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 3289627 B1

[0002]

Claims

[1] Method for drying at least one battery material with a drying device (10), in particular an industrial drying device (12), comprising at least the following steps: Drying (100) of the battery material in a low temperature and / or low pressure range, wherein in at least one drying step (120) low-boiling substances are removed from the battery material, wherein in at least one further drying step (122) high boiling points are removed from the battery material. [2] Method according to claim 1, characterized by , that the drying step (120) to remove the low-boiling substances and the drying step (122) to remove the high-boiling substances are carried out in a single drying container (30) of the dryer device (10) and / or in a batch operation. [3] Method according to claim 1 or 2, characterized by, that the drying step (122) for the removal of the high boiling points is carried out at a higher temperature (162) than the drying step (120) for the removal of the low boiling points. [4] Method according to any one of the preceding claims, characterized by , that in the drying step (122) for the removal of the high boiling points the drying takes place at least to a substantial extent at a temperature (162) of at least 80 °C. [5] Method according to any one of the preceding claims, characterized by , that in the drying step (120) to remove the low boiling points, the drying takes place at least to a significant extent at a temperature (160) of no more than 80 °C. [6] Method according to any one of the preceding claims, characterized by , that the pressure (180) in the drying step (122) for the removal of the high boiling points is set lower than in the drying step (120) for the removal of the low boiling points. [7] Method according to any one of the preceding claims, characterized by , that a fluid generated in the drying step (120) for the removal of the low-boiling substances and / or in the drying step (122) for the removal of the high-boiling substances is purified by a purification unit (18), in particular of at least hydrogen fluoride. [8] Method according to any one of the preceding claims, characterized by , that after at least one drying cycle (220), by opening a closure unit (80) of at least one drying container (30), at least one drying container (30) is cleaned and / or serviced. [9] Drying device (10), in particular industrial drying device (12), for drying at least one battery material, in particular at least partially for carrying out the method according to one of the preceding claims, comprising a vacuum unit (20) and / or a heating unit (50), and a control and / or regulating unit (60) which is provided to regulate the vacuum unit (20) and / or the heating unit (50) in a low temperature range and / or low pressure range, characterized by , that the control and / or regulating unit (60) controls the vacuum unit (20) and / or the heating unit (50) in multiple stages during the drying of the battery material. [10] Drying device (10) according to claim 9, characterized byat least one drying container (30) in which a pressure can be set by means of the vacuum unit (20) which has at least one closure unit (80) which is designed to be at least substantially openable for cleaning and / or maintenance of the drying container (30). [11] Drying device (10) according to one of claims 9 to 10, characterized by at least one sensor unit (62) which is at least intended to detect at least one drying parameter, in particular a temperature, humidity and / or a gas composition, in the drying container (30), wherein the control and / or regulating unit (30) performs the multi-stage control based on the drying parameters. [12] Battery recycling system (90) at least for carrying out the method according to one of claims 1 to 8 with a dryer device (10) according to one of claims 9 to 11. [13] Battery recycling system (90) according to claim 12, characterized bya comminution device (14) which is intended to provide comminution material of the battery material, wherein the drying device (10) is intended to dry the comminution material. [14] Control and / or regulating unit (60), in particular at least partially of the dryer device (10) according to one of claims 11 to 13, for carrying out the method according to one of claims 1 to 8.

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