Method for manufacturing black powder from waste battery

Abstract

The present invention relates to a method and system for manufacturing high-purity black powder from a waste battery. The manufacturing method and system can easily separate and remove a positive electrode current collector from a positive electrode scrap by using a predetermined organic solvent, and can selectively remove a carbon-based compound such as a conductive material or a binder from black powder from which the positive electrode current collector is removed, thus enabling the manufacture of high-purity black powder from which metals derived from a positive electrode can be easily recovered. In addition, the manufacturing method and system have the advantage of being eco-friendly since the organic solvent used during the process is reused.

Description

Method for producing black powder from waste batteries

[0001] The present invention relates to an environmentally friendly method for producing black powder having a significantly low content of carbon compounds from positive electrode scrap derived from waste batteries.

[0002] This application claims the benefit of priority to Republic of Korea Patent Application No. 10-2023-0167700, filed November 28, 2023, the entire contents of which are incorporated herein by reference.

[0003]

[0004] Lithium secondary batteries are widely used in various industries due to their high energy density, high electromotive force, and high-capacity energy storage capabilities. For example, lithium secondary batteries are used in a wide range of applications, from small portable devices like smartphones and laptops to electric vehicles (EVs), which are expected to eventually replace today's fossil fuel-powered vehicles. Consequently, lithium secondary battery production is also steadily increasing.

[0005] However, these lithium secondary batteries have a limited lifespan, and the number of expired lithium secondary batteries is expected to increase. Accordingly, efforts are being made to utilize spent lithium secondary batteries for environmental and / or economic reasons.

[0006] One example is the Toxco process, which recovers lithium from anodes. This process involves cooling a spent lithium secondary battery to -195°C with liquid argon, then immersing it in a sodium hydroxide (NaOH) solution to break the battery case. The lithium fragments from the cathode inside the battery case are then floated on the solution, generating hydrogen gas. As the hydrogen gas is released, it reacts with the sodium hydroxide (NaOH) in the solution, allowing lithium to be recovered in the form of lithium hydroxide (LiOH), lithium sulfide (Li2SO4), lithium carbonate (Li2CO3), and the like. While this process is stable, it is complex, requires excessive amounts of water, and produces a large number of byproducts, such as exhaust gases.

[0007] Another example is Sony's process, which separates metal components by washing the combustion products generated by burning spent batteries. This process recovers the metal components remaining in the combustion products after burning spent batteries through washing. It can easily remove components such as organic electrolytes, lithium, and fluoride without requiring a separate process, and easily recover only metal components, particularly cobalt.

[0008] However, despite these advantages, the process requires excessive amounts of materials such as water and heat energy, and the large amount of waste generated after the process, such as exhaust gases and cleaning solutions, can cause environmental pollution, hindering its industrial application. Furthermore, these processes are not highly efficient, and the difficulty in selectively separating only the metal components derived from the cathode active material limits the purity of the resulting product.

[0009]

[0010] [Prior Art Literature]

[0011] Republic of Korea Patent No. 10-2588151

[0012] Republic of Korea Patent Publication No. 10-2022-0038442

[0013]

[0014] Accordingly, the purpose of the present invention is

[0015] The present invention provides a technology for environmentally friendly manufacturing of black powder capable of selectively recovering and / or separating only metal components from positive electrode scrap derived from waste lithium secondary batteries.

[0016]

[0017] To solve the above-mentioned problem,

[0018] In one embodiment of the present invention,

[0019] A method for producing black powder from positive electrode scrap derived from waste batteries,

[0020] A step (S1) of stirring a mixture of positive electrode scrap and an organic solvent at a temperature of 150°C or lower to detach the positive electrode collector contained in the positive electrode scrap and to elute the conductive material and binder contained inside the black powder with an organic solvent.

[0021] Step (S2) of filtering the above mixture to separate the positive electrode collector;

[0022] A step (S3) of obtaining a black powder by separating an organic solvent containing a conductive material and a binder from the above mixture from which the positive electrode collector is separated, and

[0023] A step (S4) of separating the conductive material and the binder from the organic solvent containing the conductive material and the binder and recovering the organic solvent;

[0024] The organic solvent recovered in the above step (S4) is reused in at least one of the steps (S1) to (S3);

[0025] The above organic solvent provides a method for producing a black powder including at least one of trimethyl phosphate (TMP), triethyl phosphate (TEP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO).

[0026] At this time, the positive electrode scrap can be mixed with 200 mL to 900 mL of organic solvent per 100 g.

[0027] Additionally, the above step (S1) can be performed under conditions of 200 rpm to 1,000 rpm for 5 to 100 minutes.

[0028] In addition, the step (S3) of obtaining the black powder may include a step (S3-1) of centrifuging a mixture from which the positive electrode collector is separated, a step (S3-2) of decanting the supernatant of the centrifuged mixture to separate an organic solvent containing a conductive agent and a binder, and a step (S3-3) of filtering and washing the residue from which the supernatant is decanted to produce black powder.

[0029] Here, washing of the residue can be performed twice or more repeatedly with the same organic solvent as the organic solvent of the mixture.

[0030] In addition, the method for manufacturing the black powder may further include, after the step (S3) of obtaining the black powder, a step (S5) of further separating a conductive material included in the obtained black powder, and the further separation may be performed through a flotation selection method.

[0031] Here, the step (S5) of further separating the conductive material may include a step (S5-1) of mixing black powder and a floating additive in a hydrophilic solvent to float the conductive material in the black powder to the top of the solution, and a step (S5-2) of removing the conductive material floated to the top of the solution.

[0032] Additionally, the black powder may be mixed in an amount of 0.1 wt% to 50 wt% based on the weight of the hydrophilic solvent, and the floating additive may be mixed in an amount of 0.1 vol% to 40 vol% based on the volume of the hydrophilic solvent.

[0033] In addition, the hydrophilic solvent is water and C 1~4 The alkyl alcohol may include at least one of the following: mineral oil, trimethyl phosphate (TMP), and triethyl phosphate (TEP).

[0034] Additionally, the step (S4) of recovering the organic solvent can be performed by distilling the organic solvent containing the conductive agent and the binder under reduced pressure.

[0035] In addition, the black powder manufactured according to the present invention may have a carbon element content of less than 5 wt% when analyzed by component analysis.

[0036]

[0037] Furthermore, in one embodiment of the present invention,

[0038] In a system for manufacturing black powder from positive electrode scrap derived from waste batteries,

[0039] A stirring section that stirs a mixture of positive electrode scrap and an organic solvent to detach the positive electrode collector contained in the positive electrode scrap and elute the conductive material and binder contained inside the black powder into the organic solvent.

[0040] A filter unit that is fluidly connected to the above stirring unit and receives a stirred mixture, and filters out the positive electrode current collector from the provided mixture;

[0041] A separation unit that is fluidly connected to the above filter unit and receives a separated mixture of a cathode current collector and separates an organic solvent containing a conductive agent and a binder from the provided mixture to obtain a black powder, and

[0042] A distillation unit is included for separating the conductive agent and binder from the organic solvent separated in the above separation unit and recovering the organic solvent;

[0043] The organic solvent recovered from the distillation unit is supplied to at least one of the stirring unit, the filtering unit, and the separation unit and reused;

[0044] The above organic solvent provides a black powder production system including at least one of trimethyl phosphate (TMP), triethyl phosphate (TEP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO).

[0045] At this time, the separation unit may include a centrifuge.

[0046] Additionally, the distillation unit may be fluidly connected to the top of the centrifuge to provide a supernatant after centrifugation of the mixture.

[0047] In addition, the separation unit may include a filter that supports the residue of the mixture from which the supernatant has been removed after centrifugation at the bottom, and the distillation unit may be fluidly connected to the bottom of the filter to receive a washing liquid when washing the residue supported on the filter.

[0048] In addition, the black powder manufacturing system may further include a flotation separation unit that is fluidly connected to the separation unit to receive black powder and perform flotation separation to further remove a conductive material from the provided black powder.

[0049] Furthermore, the distillation unit may include a reduced pressure distillation device.

[0050]

[0051] The method and system for manufacturing black powder according to the present invention can easily separate and remove a positive electrode current collector from positive electrode scrap using a predetermined organic solvent, and can selectively remove carbon-based compounds such as conductive materials and binders from the black powder from which the positive electrode current collector has been removed, thereby manufacturing a high-purity black powder from which metals derived from the positive electrode can be easily recovered. In addition, the manufacturing method and system have the advantage of being environmentally friendly because the organic solvent used during the process is reused.

[0052]

[0053] Figure 1 is an image of black powder manufactured according to Example 2 of the present invention.

[0054] Figure 2 is an image of a conductive material floating on top of a mixed solution taken by a floating separation method according to the present invention.

[0055]

[0056] The present invention can be modified in various ways and has many embodiments, and specific embodiments will be described in detail in the detailed description.

[0057] However, this is not intended to limit the present invention to a specific embodiment, but should be understood to include all modifications, equivalents, or substitutes included in the technical scope of the present invention.

[0058] In the present invention, it should be understood that terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0059] Additionally, in the present invention, when a part such as a layer, film, region, or plate is described as being "on" another part, this includes not only cases where it is "directly above" the other part, but also cases where there is another part in between. Conversely, when a part such as a layer, film, region, or plate is described as being "under" another part, this includes not only cases where it is "directly below" the other part, but also cases where there is another part in between. Furthermore, in the present application, "on" may include cases where it is placed below as well as above.

[0060]

[0061] Hereinafter, the present invention will be described in more detail.

[0062]

[0063] Method for manufacturing black powder

[0064] In one embodiment of the present invention,

[0065] A method for producing black powder from positive electrode scrap derived from waste batteries,

[0066] A step (S1) of stirring a mixture of positive electrode scrap and an organic solvent at a temperature of 150°C or lower to detach the positive electrode collector contained in the positive electrode scrap and to elute the conductive material and binder contained inside the black powder with an organic solvent.

[0067] Step (S2) of filtering the above mixture to separate the positive electrode collector;

[0068] A step (S3) of obtaining a black powder by separating an organic solvent containing a conductive material and a binder from the above mixture from which the positive electrode collector is separated, and

[0069] A step (S4) of separating the conductive material and the binder from the organic solvent containing the conductive material and the binder and recovering the organic solvent;

[0070] The organic solvent recovered in the above step (S4) is reused in at least one of the steps (S1) to (S3);

[0071] The above organic solvent provides a method for producing a black powder including at least one of trimethyl phosphate (TMP), triethyl phosphate (TEP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO).

[0072]

[0073] The method for manufacturing black powder according to the present invention refers to a method for manufacturing black powder derived from the positive electrode of a lithium secondary battery whose lifespan has expired, i.e., a waste battery, and containing a positive electrode active material as its main component.

[0074] The method for manufacturing the above black powder includes a step of mixing a positive electrode scrap derived from a positive electrode of a spent battery and a predetermined organic solvent and stirring the mixture at a temperature of 150°C or lower to detach the positive electrode collector from the positive electrode scrap, and eluting the conductive material and binder contained within the black powder with the organic solvent (S1).

[0075] This step (S1) refers to the process of detaching and separating the positive electrode collector from the positive electrode scrap, and dissolving the conductive material and binder inside the black powder, which is the residue, from the black powder.

[0076] Here, "black powder" refers to the black residue remaining after removing the positive electrode current collector from the positive electrode separated from a used battery. This black powder originates from the positive electrode active layer containing the positive electrode active material, and thus contains carbon-based compounds such as conductive agents such as carbon black and binders such as polyvinylidene fluoride (PVdF) along with the positive electrode active material as the main component.

[0077] In general, black powder contains metals such as lithium, nickel, cobalt, and manganese as its main components, and is used to recover and recycle these metals. At this time, the metal recovery efficiency and purity of the recovered metal are higher when the black powder contains less impurities other than the metal (i.e., carbon-based compounds containing carbon contained in the binder, etc., and / or non-metallic compounds such as fluorine (F) and phosphorus (P)). Therefore, a technology is being utilized to remove the conductive agent or binder by volatilizing it when heat treating the black powder at high temperatures before recovering the metal from the black powder. However, the high-temperature volatilization method can cause damage to the equipment due to trace amounts of hydrogen fluoride (HF) gas generated during the thermal decomposition of binders such as polyvinylidene fluoride (PVdF), and can induce side reactions in the generated black powder, which can have negative effects. In addition, the high-temperature volatilization method is likely to cause the conductive agent or binder inside the black powder to not be completely volatilized and to remain. Therefore, the above high-temperature volatilization method requires a considerable amount of heat energy to completely remove the conductive material or binder inside the black powder, so it has low economic feasibility, can cause side reactions of metals contained in the black powder, and has limitations in being harmful to the environment.

[0078] However, the method for manufacturing black powder according to the present invention can easily separate / remove the positive electrode current collector by adding a predetermined organic solvent to the positive electrode scrap from which the positive electrode current collector has been crushed. In addition, the organic solvent added to the positive electrode scrap can efficiently dissolve the conductive material and binder in the residue of the positive electrode scrap from which the positive electrode current collector has been separated, i.e., the black powder, thereby dissolving them from the black powder.

[0079] At this time, the organic solvent may be mixed with the positive electrode scrap and stirred at a predetermined temperature range. Specifically, the organic solvent may be mixed with the positive electrode scrap and stirred at a temperature of 150°C or lower, and more specifically, the organic solvent may be mixed with the positive electrode scrap and stirred at a temperature of 50°C to 150°C; 80°C to 150°C; 100°C to 150°C; 120°C to 150°C; 50°C to 120°C; 50°C to 100°C; 70°C to 130°C; or 85°C to 115°C.

[0080] In order to detach the positive electrode current collector from the positive electrode scrap, the dissolution of the binder distributed at the interface between the positive electrode current collector and the positive electrode active layer is essential. Furthermore, in order to reduce the content of non-metallic compounds such as conductive agents or binders in the positive electrode active layer remaining after the positive electrode current collector is detached from the positive electrode scrap, i.e., the black powder, it is preferable to separate them using an organic solvent. Accordingly, the present invention can increase the molecular momentum of the organic solvent mixed with the positive electrode scrap to facilitate the dissolution of the conductive agent and binder from the black powder. Here, the molecular momentum of the organic solvent can be implemented by the stirring speed or temperature conditions of the mixture of the positive electrode scrap and the organic solvent, etc.

[0081] Conventionally, methods such as sonication have been applied to separate the positive electrode current collector and black powder. However, although the ultrasonic irradiation has the advantage of rapidly dissolving the binder located at the interface between the positive electrode current collector and the positive electrode active layer, it has the problem of inducing damage to the positive electrode current collector itself, resulting in a significant increase in impurities such as aluminum (Al) derived from the positive electrode current collector within the black powder. In addition, the eluted conductive agent and / or binder may undergo a side reaction on the surface of the black powder through ultrasonic irradiation, thereby being fixed or uniformly dispersed in an organic solvent. In this form, even if the black powder and the organic solvent are separated, a significant amount of the conductive agent and binder remain in the black powder, which has the limitation of actually reducing the content of metal components contained in the black powder.

[0082] However, the present invention not only facilitates the separation of the positive electrode current collector from the positive electrode scrap by increasing the molecular momentum of the organic solvent itself mixed with the positive electrode scrap through the stirring speed and / or temperature control, but also enables the removal of the conductive material and binder from the black powder residue with high efficiency. To this end, the mixture of the positive electrode scrap and the organic solvent can be stirred within a predetermined temperature range.

[0083] In addition, the organic solvent may be a polar solvent that has a boiling point (bp) higher than the temperature conditions under which stirring is performed and can easily dissolve inorganic salts, acid bases, transition metal complexes, etc. For example, the organic solvent may include one or more of trimethyl phosphate (TMP), triethyl phosphate (TEP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO).

[0084] As an example, the organic solvent may be triethyl phosphate (TEP) or dimethyl sulfoxide (DMSO). Triethyl phosphate and dimethyl sulfoxide are relatively less toxic than other organic solvents and have a low Hansen solubility parameter (Ra), making them suitable for dissolving conductive materials and / or binders present within the black powder. Here, the Hansen solubility parameter (Ra) represents the distance between binder molecules, such as polyvinylidene fluoride (PVdF), and solvent molecules in a three-dimensional Hansen space.

[0085] Additionally, the mixture of the positive electrode scrap and the organic solvent may be stirred at a predetermined speed for a predetermined period of time. Specifically, this step (S1) may be performed at a speed of 200 rpm to 1,000 rpm for 5 to 100 minutes.

[0086] More specifically, the present step (S1) may be stirred for 5 to 90 minutes; 5 to 60 minutes; 5 to 30 minutes; 5 to 15 minutes; 10 to 100 minutes; 30 to 100 minutes; 60 to 100 minutes; 10 to 50 minutes; 30 to 60 minutes; 70 to 90 minutes; 15 to 60 minutes; or 20 to 40 minutes.

[0087] Additionally, the stirring may be performed at a speed of 200 rpm to 900 rpm; 200 rpm to 500 rpm; 200 rpm to 400 rpm; 500 rpm to 1,000 rpm; 700 rpm to 1,000 rpm; 400 rpm to 800 rpm; or 300 rpm to 700 rpm.

[0088] Furthermore, the positive electrode scrap and the organic solvent may be mixed at a predetermined ratio. For example, the positive electrode scrap may be mixed with 200 mL to 900 mL of the organic solvent per 100 g. More specifically, the positive electrode scrap may be mixed at a ratio of 200 mL to 800 mL; 200 mL to 600 mL; 200 mL to 400 mL; 450 mL to 900 mL; 600 mL to 900 mL; 300 mL to 700 mL; or 400 mL to 600 mL per 100 g.

[0089] The present invention can more easily separate the positive current collector contained in the positive electrode scrap from the black powder by stirring the mixture containing the positive electrode scrap and the organic solvent so as to satisfy the conditions described above, and can elute the conductive material and binder contained within the black powder with the organic solvent.

[0090] In addition, the method for manufacturing the black powder includes a step (S2) of filtering the previously stirred mixture to separate the positive electrode collector.

[0091] This step (S2) refers to the process of removing the cathode current collector detached from the cathode scrap through stirring with an organic solvent.

[0092] The above positive electrode collector can be separated through filtration, and the filtration can be performed using at least one of a filter and a filter having a condition that only the separated positive electrode collector cannot pass through.

[0093] The above-mentioned filtered positive electrode collector can be washed with the same component as the organic solvent included in the mixture during the filtration process, and can be collected separately and regenerated after filtration. Specifically, the regeneration of the positive electrode collector is performed by first collecting the positive electrode collector separated by filtration separately. Then, the collected positive electrode collector is placed in an organic solvent and stirred at a speed of 400 to 500 rpm at 150 to 250°C. After the stirring is completed, the positive electrode collector is irradiated with ultrasonic waves for 10 to 60 minutes while still placed in the organic solvent, and then washed, thereby being regenerated. At this time, the organic solvent used for placing and washing the positive electrode collector may be the same as the organic solvent mixed with the positive electrode scrap. In addition, the ultrasonic irradiation may be performed under conditions of power of 0.5 to 16 kW and a frequency of 15 KHz to 50 KHz.

[0094] In addition, the method for manufacturing the black powder includes a step (S3) of obtaining black powder by separating an organic solvent containing a conductive material and a binder from a mixture from which a positive electrode collector is separated.

[0095] At this time, the method for separating the organic solvent containing the above-mentioned conductive agent and binder is not particularly limited, but may preferably be a method using a centrifugal separation method.

[0096] Since the organic solvent above has a form in which the binder is uniformly dissolved, it can be separated together with the binder at once through filtration or the like. However, since the conductive material is dispersed in the organic solvent, it is difficult to separate the conductive material through general filtration.

[0097] Accordingly, the present invention can separate the conductive agent and binder within the black powder along with the organic solvent by centrifuging a mixture of black powder and an organic solvent and then separating the supernatant. Specifically, this step (S3) can be performed by the following process:

[0098] Step (S3-1) of centrifuging the mixture from which the positive electrode collector is separated;

[0099] A step (S3-2) of separating the organic solvent containing the conductive agent and binder by decanting the supernatant of the centrifuged mixture, and

[0100] Step (S3-3) of manufacturing black powder by filtering and washing the decanted residue of the supernatant.

[0101]

[0102] In this step (S3), the supernatant of the centrifuged mixture is decanted to separate the residue (e.g., solid content), which can be further filtered and washed to remove the conductive agent and binder remaining on the surface.

[0103] At this time, the washing can be repeated two or more times, specifically 2 to 5 times, with the same component as the organic solvent separated from the mixture, and the amount of organic solvent used during washing can be applied in an amount of 60 to 200 wt%, specifically 60 to 150 wt%, based on the weight of the black powder being washed.

[0104] Furthermore, the method for manufacturing black powder of the present invention may further include a step (S5) of further separating a conductive material included in the black powder obtained in step (S3) in order to further reduce the content of carbon compounds in the manufactured black powder.

[0105] At this time, the additional separation can be performed through a flotation method. The flotation method refers to a method of separation by utilizing differences in the physicochemical properties of the particle surface. This method can selectively separate the particles by selectively attaching bubbles and / or droplets to the surface of the particles to be separated by utilizing significant differences in wettability of the particle surface, and then floating the particles to which the bubbles and / or droplets are attached. Conventional sedimentation separation methods that utilize differences in the density / specific gravity of the particles to be separated or solution layer separation methods using hydrophilic and hydrophobic solutions have the problem of low efficiency in separating trace amounts of conductive material remaining in the black powder. Furthermore, these methods have the problem of requiring a significant amount of solvent for their separation because the boundary between the heterogeneous materials to be separated is unclear during the process, which leads to a problem of significantly large amounts of waste generated. However, the flotation method not only uses a significantly smaller amount of solvent during the process, but also has the advantage of being able to highly efficiently separate the conductive material within the black powder by means of bubbles and / or droplets.

[0106] Here, the bubbles may be formed by distributing a floating additive mixed in a hydrophilic solvent on the outer surface of a given air / gas, and may have a foam-like shape. In addition, the droplets may be formed by dispersing the floating additive itself in a hydrophilic solvent.

[0107] Accordingly, this step (S5) may include a step (S5-1) of mixing black powder and a floating additive in a hydrophilic solvent to float the conductive material in the black powder to the top of the solution, and a step (S5-2) of removing the conductive material floated to the top of the solution.

[0108] The black powder may include a metal and / or metal compound as the main component and a conductive material which is a carbon-based compound, wherein the metal and / or metal compound exhibits hydrophilicity while the carbon-based compound exhibits relatively hydrophobicity.

[0109] Accordingly, in this step (S5), black powder and a buoyant additive may be mixed in a hydrophilic solvent to generate bubbles and / or droplets within the solution. The bubbles and / or droplets thus generated may attach to the surface of the conductive material and float to the top of the solution (S5-1). Specifically, the black powder and a buoyant additive may be mixed in a hydrophilic solvent and stirred for a predetermined period of time so that the generated bubbles and / or droplets attach to the hydrophobic surface of the conductive material. After the stirring is completed, the conductive material may float to the top of the solution by the bubbles and / or droplets attached to the surface. By capturing the suspended bubbles and / or droplets at the top of the solution (S5-2), the conductive material remaining within the black powder may be additionally removed.

[0110] Here, the amount and / or efficiency of the conductive material attached to the bubbles may vary depending on the content of the hydrophilic solvent and the buoyancy additive mixed with the black powder, the stirring speed for bubble generation and buoyancy, etc. of the above-mentioned floating sorting method.

[0111] Accordingly, in order to further reduce the content of the conductive agent remaining in the black powder, the content of the black powder and the floating additive mixed in the hydrophilic solvent, the stirring speed, and the stirring time can be adjusted to satisfy predetermined conditions.

[0112] As an example, the black powder may be mixed in an amount of 0.1 wt% to 50 wt% based on the weight of the hydrophilic solvent, and the floating additive may be mixed in an amount of 0.1 vol% to 40 vol% based on the volume of the hydrophilic solvent.

[0113] Specifically, the black powder is present in an amount of 0.1 wt% to 40 wt%, 0.1 wt% to 30 wt%, 0.1 wt% to 25 wt%, 0.1 wt% to 20 wt%, 0.1 wt% to 15 wt%, 0.1 wt% to 10 wt%, 0.1 wt% to 9 wt%, 0.1 wt% to 5 wt%, 0.5 wt% to 10 wt%, 1 wt% to 10 wt%, 5 wt% to 20 wt%, 10 wt% to 30 wt%, 20 wt% to 40 wt%, 30 wt% to 40 wt%, 11 wt% to 19 wt%, 1 wt% to 5 wt%, 1 wt% to 3 wt%, 0.5 wt% to 5 wt%, 0.5 wt% to 3 wt%, It can be mixed at 0.1 wt% to 3 wt%, or 0.1 wt% to 1 wt%.

[0114] In addition, the floating additive may be mixed in an amount of 0.1% to 30% by volume, 0.1% to 20% by volume, 0.1% to 10% by volume, 0.1% to 9% by volume, 2% to 9% by volume, 4% to 15% by volume, 10% to 20% by volume, 10% to 30% by volume, 20% to 40% by volume, 25% to 35% by volume, 15% to 25% by volume, 1% to 6% by volume, 0.1% to 2% by volume, or 2% to 7% by volume based on the volume of the hydrophilic solvent.

[0115] As another example, stirring of a mixed solution containing black powder, a hydrophilic solvent, and a floating additive can be performed at a speed of 500 rpm to 5,000 rpm for 1 minute to 100 minutes.

[0116] Specifically, the stirring of the mixed solution may be performed for 1 minute to 90 minutes; 1 minute to 80 minutes; 1 minute to 60 minutes; 1 minute to 40 minutes; 1 minute to 30 minutes; 1 minute to 20 minutes; 1 minute to 15 minutes; 1 minute to 10 minutes; 1 minute to 5 minutes; 2 minutes to 7 minutes; 5 minutes to 10 minutes; 10 minutes to 30 minutes; 20 minutes to 60 minutes; 50 minutes to 100 minutes; 5 minutes to 15 minutes; or 1 minute to 9 minutes.

[0117] Additionally, the stirring of the mixed solution may be performed at a speed of 500 rpm to 4,000 rpm; 500 rpm to 3,000 rpm; 500 rpm to 2,500 rpm; 500 rpm to 2,000 rpm; 500 rpm to 1,500 rpm; 500 rpm to 1,000 rpm; 2,500 rpm to 5,000 rpm; 3,000 rpm to 5,000 rpm; 2,000 rpm to 4,000 rpm; 1,000 rpm to 3,000 rpm; 700 rpm to 1,500 rpm; or 500 rpm to 1.80 rpm.

[0118] The present invention can effectively separate a small amount of conductive material remaining inside black powder during flotation with less energy by controlling the content ratio of each component and / or stirring conditions as described above.

[0119] Meanwhile, the hydrophilic solvent is C such as water, methanol, and ethanol. 1~4 It may include at least one type of alkyl alcohol. The hydrophilic solvent not only has high wettability for the black powder, but also has the characteristic of being an environmentally friendly solvent.

[0120] In addition, the buoyancy additive can form bubbles and / or droplets in a hydrophilic solvent, while at the same time attaching a hydrophobic conductive material to the bubble surface. Such buoyancy additives may include at least one selected from the group consisting of mineral oil, trimethyl phosphate (TMP), and triethyl phosphate (TEP). Since the buoyancy additives have a relatively low affinity for hydrophilic solvents compared to formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO), the buoyancy additives can easily induce the formation of bubbles and / or droplets within the hydrophilic solvent during stirring. In addition, since the buoyancy additives have a high affinity for conductive materials, the conductive material present in the black powder can be attached to the bubbles with high efficiency.

[0121] For example, trimethyl phosphate (TMP) and / or triethyl phosphate (TEP) as the above-mentioned floating additives can be mixed with a hydrophilic solvent to form microbubbles, and the microbubbles thus formed can easily attach to the surface of the conductive material and float the conductive material to the top of the solution.

[0122] In addition, when the mineral oil is mixed alone with a hydrophilic solvent, it can form fine droplets and form an emulsion with the hydrophilic solvent. The droplets have hydrophobic properties and thus have a high affinity for the conductive material, so they can attach to the surface of the conductive material and float to the top of the solution. In addition, when the mineral oil is used in combination with trimethyl phosphate (TMP) and / or triethyl phosphate (TEP), it can be mixed with the hydrophilic solvent to form fine bubbles. The fine bubbles formed in this process can easily attach to the surface of the conductive material and float the conductive material to the top of the solution.

[0123] Meanwhile, the bubbles and / or droplets floating to the top of the mixed solution may have a structure in which the outside is surrounded by a floating additive or may be composed of a floating additive itself, and may have a form in which a conductive agent remaining inside the black powder is attached by the floating additive. Accordingly, the mixed solution from which the bubbles and / or droplets have been removed may be composed of black powder from which the conductive agent has been removed and a hydrophilic solvent.

[0124] The mixed solution from which bubbles and / or droplets have been removed can be used to separate the hydrophilic solvent through distillation or other methods, thereby producing a black powder having a significantly lower content of carbon compounds.

[0125] The black powder obtained in this way may have a significantly low content of conductive material and binder, and when analyzing the components, the positive electrode active material contained in the positive electrode may be detected as the main component.

[0126] As an example, the black powder may have a carbon (C) element content of less than 5 wt% when analyzed by component analysis using X-ray photoelectron spectroscopy (XPS), and specifically, may have a content of 0.01 to 5 wt%, 0.01 to 3 wt%, 0.01 to 1 wt%, 0.5 to 3 wt%, 1 to 4 wt%, or 3 to 5 wt%.

[0127] Furthermore, the method for manufacturing the black powder includes a step (S4) of separating the conductive agent and binder from the organic solvent separated from the black powder and recovering the organic solvent. This step (S4) refers to a process of purifying the separated organic solvent.

[0128] Here, the present step (S4) can be applied without particular limitation as long as it is a method capable of separating the organic solvent from the conductive agent and binder, but it can be preferably performed through reduced pressure distillation. The reduced pressure distillation can selectively volatilize the organic solvent introduced into the reactor by lowering the pressure inside the reactor to a vacuum or close to a vacuum and controlling the temperature to the boiling point (bp) of the organic solvent or a temperature slightly lower than the boiling point (bp). The organic solvent thus volatilized can be condensed by a cooler located at the top of the reactor and recovered again, and the recovered organic solvent can have a high purity of 90% or more, for example, 95% or more, 98% or more, or 99% or more, and does not contain the conductive agent or binder.

[0129] Since the organic solvent has a high purity, it can be reused in the process of manufacturing the black powder according to the present invention. Specifically, the recovered organic solvent can be used in the process of producing a mixture of positive electrode scrap in step (S1) and in the process of washing the positive electrode current collector separated in step (S2). In addition, the recovered organic solvent can be used in the process of filtering and / or washing the black powder separated from the organic solvent in step (S3).

[0130] The present invention is not only environmentally friendly because it can significantly reduce the amount of waste generated in the process of manufacturing black powder by reusing recovered organic solvents, but also has economic advantages because it consumes less raw materials used in the process.

[0131]

[0132] The method for manufacturing black powder according to the present invention, having the above-described configuration, enables easy separation and removal of the positive electrode current collector from positive electrode scrap, and highly efficiently separates and removes the positive electrode conductive material and binder from the black powder from which the positive electrode current collector has been removed, thereby enabling the production of high-purity black powder. Furthermore, the manufacturing method has the advantage of being environmentally friendly, as it reuses the organic solvent used during the process.

[0133]

[0134] Black Powder Manufacturing System

[0135] Furthermore, in an embodiment of the present invention,

[0136] A system for recovering black powder from positive electrode scrap derived from waste batteries.

[0137] A stirring section that stirs a mixture of positive electrode scrap and an organic solvent to detach the positive electrode collector contained in the positive electrode scrap and elute the conductive material and binder contained inside the black powder into the organic solvent.

[0138] A filter unit that is fluidly connected to the above stirring unit and receives a stirred mixture, and filters out the positive electrode current collector from the provided mixture;

[0139] A separation unit that is fluidly connected to the above filter unit and receives a separated mixture of a cathode current collector and separates an organic solvent containing a conductive agent and a binder from the provided mixture to obtain a black powder, and

[0140] A black powder manufacturing system is provided, which includes a distillation unit for separating a conductive agent and a binder from an organic solvent separated in the above separation unit and recovering the organic solvent.

[0141]

[0142] The above black powder manufacturing system is for performing the black powder manufacturing method of the present invention described above.

[0143] Specifically, the above black powder manufacturing system can detach a positive electrode current collector from the positive electrode scrap and elute a conductive material and a binder from the black powder residue with an organic solvent by stirring a mixture of positive electrode scrap derived from a waste battery and a predetermined organic solvent at a temperature of 150°C or lower in a stirring unit.

[0144] At this time, the stirring unit may include a dispersion blade mixer, a stirring mixer, a screw mixer, a conical screw mixer, a planetary stirring mixer, an air jet mixer, a high shearing mixer, etc. for stirring the mixture.

[0145] Additionally, the stirring unit may include a temperature control device to provide appropriate thermal energy to the mixture being stirred. The temperature control device is positioned outside the stirring unit and controls the temperature of the outer surface of the stirring unit, thereby providing thermal energy to the mixture being stirred inside the stirring unit. In addition, the temperature control device is electrically connected to a temperature measuring device located inside the stirring unit and can control the temperature of the outer surface of the stirring unit according to the temperature inside the stirring unit.

[0146] In addition, the above black powder manufacturing system can remove the cathode current collector detached from the cathode scrap by transferring the mixture stirred in the stirring unit to the filter unit and filtering it. At this time, the filter unit can be applied without particular limitation as long as it has a form capable of filtering the cathode current collector.

[0147] For example, the filtering unit may include a filter or strainer for filtering out the positive electrode current collector at the bottom, and the filter or strainer may have holes having a size ratio of 40% to 80% based on the average size of the positive electrode current collector contained in the positive electrode scrap to pass materials other than the positive electrode scrap.

[0148] In addition, the above black powder manufacturing system can manufacture black powder by moving a mixture from which the positive electrode collector has been removed to a separation unit and then separating an organic solvent containing a conductive material and a binder.

[0149] At this time, the separation unit may include a centrifuge to separate the black powder and the organic solvent.

[0150] Since the organic solvent of the mixture provided in the above filtration unit has a form in which the binder is uniformly dissolved, it can be separated together with the binder through filtration or the like. However, since the conductive agent is dispersed in the organic solvent, it is difficult to separate the conductive agent when separating the organic solvent through general filtration. However, the present invention can separate the conductive agent and binder in the black powder together with the organic solvent by centrifuging the mixture of the black powder and the organic solvent using a centrifuge and then separating the supernatant.

[0151] For this purpose, the separation unit may include a centrifuge, and the upper part of the centrifuge may be fluidly connected so that the supernatant of the centrifuged mixture can be separated and provided to the distillation unit.

[0152] In addition, the separation unit may include a filter that supports and filters the black powder at the bottom to increase the purity of the mixture, i.e., the black powder, remaining after the supernatant is separated, and allows organic solvents remaining in the black powder to pass therethrough.

[0153] The above separation unit may be equipped with a filter at the bottom to wash the black powder filtered inside with an organic solvent, thereby further improving the purity of the black powder. Here, a pipe may be introduced at the bottom of the separation unit, specifically, at the bottom of the filter, to allow the residual organic solvent and washing liquid passing through the filter to flow to the distillation unit.

[0154] The above black powder manufacturing system may further include means for further removing a conductive material from the black powder obtained from the separation unit in order to further reduce the content of carbon-based compounds, specifically, conductive material, present in the black powder.

[0155] For example, the black powder manufacturing system may further include a flotation separation unit for additionally removing a conductive material from the black powder.

[0156] The above flotation unit may be fluidly connected to the separation unit to receive the black powder obtained from the separation unit, and may provide a space in which the provided black powder, a hydrophilic solvent, and a flotation additive are mixed to generate bubbles. Specifically, the flotation unit may include a reaction tank in which the black powder provided from the separation unit, a hydrophilic solvent, and a flotation additive are mixed.

[0157] The above reactor may include a stirring means such as a dispersion blade mixer, a stirring mixer, a screw mixer, a conical screw mixer, a planetary stirring mixer, an air jet mixer, or a high shearing mixer on the lower surface for mixing black powder, a hydrophilic solvent, and a floating additive.

[0158] In addition, the above reactor may include a bubble catcher at the top to remove bubbles generated after stirring a mixed solution containing black powder, a hydrophilic solvent, and a floating additive and floating to the top of the mixed solution. In this case, the bubble catcher may be applied without particular limitation as long as it has a form capable of capturing bubbles floating on the solution.

[0159] In addition, the above-mentioned floating separation unit may further include a distillation means for removing the solvent of the mixed solution remaining in the reaction tank after capturing the bubbles, i.e., the hydrophilic solvent.

[0160] Furthermore, the black powder manufacturing system can purify the organic solvent provided from the separation unit by including a distillation unit. Specifically, the distillation unit can include a vacuum distillation device to recover a high-purity organic solvent from which the conductive agent and binder have been removed from the organic solvent provided from the separation unit and containing the conductive agent and binder.

[0161] At this time, the reduced pressure distillation device may include a reactor into which an organic solvent provided from a separation unit is injected, a vacuum pump located at the top of the reactor to lower the internal pressure to a vacuum or close to a vacuum, a heater located at the bottom of the reactor to provide heat below the boiling point (bp) of the organic solvent inside the reactor, a cooler located at the top of the reactor to cool and condense the volatile organic solvent, and an organic solvent storage unit that collects and stores the organic solvent condensed in the cooler.

[0162] In addition, the organic solvent storage unit of the above-described reduced pressure distillation device can store a high-purity organic solvent and supply the recovered organic solvent by being fluidly connected to at least one of the stirring unit, filtering unit, and separation unit of the black powder manufacturing system.

[0163] The organic solvent thus provided has a high purity and can therefore be reused in the process of manufacturing the black powder according to the present invention. The black powder manufacturing system of the present invention is not only environmentally friendly because it significantly reduces the amount of waste generated in the black powder manufacturing process by reusing the organic solvent, but also has economic advantages because it consumes less raw materials used in the process.

[0164] In addition, the operating conditions of the specific system for manufacturing black powder are identical to the composition of the method for manufacturing black powder described above, so a detailed description thereof is omitted.

[0165] Furthermore, the manufacturing system is a closed-loop system in which all processes are performed within a single, enclosed space. That is, when positive electrode scrap is provided to the system, the manufacturing system automatically performs each step according to preset values ​​without any separate user intervention, and ultimately discharges the positive electrode current collector separated from the generated black powder. Therefore, the manufacturing system of the present invention has the advantage of simplicity in both the processes actually performed and the processes that must be operated by the user.

[0166]

[0167] The black powder manufacturing system according to the present invention, having the above-described configuration, can easily separate and remove the positive electrode current collector from the positive electrode scrap, and can efficiently separate and remove the positive electrode conductive material and binder from the black powder from which the positive electrode current collector has been removed, thereby producing high-purity black powder. In addition, the manufacturing system has the advantage of being environmentally friendly because it reuses the organic solvent used during the process.

[0168]

[0169] Hereinafter, the present invention will be described in more detail through examples and experimental examples.

[0170] However, the following examples and experimental examples are only illustrative of the present invention, and the content of the present invention is not limited to the following examples and experimental examples.

[0171]

[0172] Examples and Comparative Examples. Method for Manufacturing Black Powder

[0173] LiNi as a cathode active material 0.6 Co 0.2 Mn 0.2 A lithium secondary battery containing O2 and reaching the end of its life was disassembled to prepare a cathode. The prepared cathode was crushed to prepare cathode scrap (average size: approximately 10–20 μm).

[0174] Afterwards, 100 g of the prepared positive electrode scrap and an organic solvent were introduced into the stirring unit of the black powder manufacturing system, and the introduced positive electrode scrap and organic solvent were stirred or ultrasonically irradiated for 30 minutes to detach the positive electrode collector from the positive electrode scrap, and the conductive material and binder contained inside the black powder were eluted into the organic solvent (S1). Here, ① the type of organic solvent mixed with the positive electrode scrap, ② the mixing amount (specifically, the mixing amount per 100 g of positive electrode scrap), and ③ the mixing method were controlled as shown in Table 1 below. In addition, ④ the internal temperature of the reactor during mixing was controlled by a temperature control device installed at the outer lower part of the reactor, as shown in Table 1. In addition, when stirring during mixing, it was performed at a speed of 400±50 rpm using a stirring mixer; and when ultrasonic irradiation was performed, it was performed at a power of 5 to 10 kW and a frequency of 5 to 10 KHz.

[0175] After mixing in the stirring unit was completed, the mixture of the positive electrode scrap and the organic solvent was transferred to the filter unit fluidly connected to the stirring unit. The mixture transferred to the filter unit passed through a filter (average hole size: approximately 5 to 10 μm) installed at the bottom of the filter unit, and through this process, the positive electrode collector separated from the positive electrode scrap was filtered out and removed (S2). The filtered positive electrode collector was dried in a vacuum oven at 150°C, and the weight of the dried positive electrode collector was measured to calculate the weight (A) of the component in the positive electrode scrap excluding the positive electrode collector.

[0176] The mixture (specifically, black powder, conductive material, binder, and organic solvent) excluding the positive electrode collector was transferred to a centrifuge in the separation unit, which was fluidly connected to the lower part of the filtration unit. The mixture transferred to the centrifuge was centrifuged at 500 to 1,000 rpm for 10 to 30 minutes. After centrifugation, the supernatant of the centrifuged mixture was transferred to the distillation unit through a fluidly connected pipe at the top of the centrifuge and separated. In addition, the residue remaining inside the centrifuge was filtered and washed with a filter installed at the lower part of the centrifuge. At this time, the washing of the residue was repeated 2 to 3 times using the same organic solvent as the organic solvent contained in the mixture at 80 to 120 wt% based on the weight of the residue. The washing solution from which the residue was washed passed through the filter and was transferred to the distillation unit through a fluidly connected pipe at the lower part of the filter.

[0177] The washed residue was collected and dried in a vacuum oven at 150°C to produce black powder (S3).

[0178] The weight (B) of the manufactured i) black powder was measured, and the recovery rate of the black powder was calculated using the weight (A) of the components excluding the positive electrode collector from the positive electrode scrap measured previously. As a result, it was confirmed that the black powder of the example had a high recovery rate of about 70% or more, while the black powder of the comparative example had a lower recovery rate.

[0179] In addition, ii) X-ray photoelectron spectroscopy (XPS) was performed on the black powder to analyze the components contained in the black powder. At this time, the X-ray photoelectron spectroscopy (XPS) was performed using Monochromated-Al-Kα (1486.6 eV) as an X-ray light source with an X-ray irradiation diameter of 400 ㎛, the energy of the Ar sputtering gun was 1,000 eV, and the etching time and speed were 3,000 seconds and 0.1±0.01 nm / s, respectively.

[0180] Among the analyzed components, the element ratios of components other than the metals that constitute the cathode active material, i.e., lithium (Li), nickel (Ni), cobalt (Co), manganese (Mn), and oxygen (O), were calculated to determine the purity of the manufactured ⑤ black powder and the ⑥ carbon element content. The results are shown in Table 1 below.

[0181] Meanwhile, the conductive agent was further removed from the black powder obtained in Example 2. Specifically, the black powder obtained in Example 2 was transferred to the reaction tank of the flotation separation unit, water was added to the reaction tank, and the mixture was stirred with a stirring mixer for 5±1 minutes. Thereafter, a buoyant additive was added to the reaction tank, and the mixture was further stirred with a stirring mixer at a speed of 1,000±100 rpm for 5±1 minutes to generate bubbles and / or droplets in the mixed solution, while the conductive agent inside the black powder was attached to the surface of the generated bubbles and / or droplets to float to the top of the solution (S5-1). At this time, a) the mixing amount of the black powder and the buoyant additive based on the total weight of the hydrophilic solvent, and b) the type of the buoyant additive were adjusted as shown in Table 2 below.

[0182] When stirring was completed, the air bubbles and / or droplets floating to the top of the mixed solution were removed to remove the conductive agent (S5-2). At this time, in order to reduce the residual amount of the air bubbles and / or droplets and the conductive agent attached thereto, water, a hydrophilic solvent, was added to the mixed solution during removal to remove the air bubbles and / or droplets.

[0183] A black powder was prepared by removing the hydrophilic solvent by distilling the mixed solution under reduced pressure from which the challenge agent was removed.

[0184] The recovery rate of the black powder manufactured in the same manner as previously performed, ⑦ the purity of the black powder, and ⑧ the carbon element content were calculated. The results are shown in Table 2 below.

[0185] Separately, the organic solvents previously delivered to the distillation unit were purified and recovered by the reduced pressure distillation device of the distillation unit, and the recovered organic solvents were reused (S4) in the process of mixing with the anode scrap. Specifically, the organic solvents were delivered to the reactor of the reduced pressure distillation device. Thereafter, the internal pressure was lowered by the vacuum pump located at the top of the reactor, and heat of 110 to 180°C was applied to the reactor to perform reduced pressure distillation of the organic solvents. The distilled organic solvents were cooled and condensed by the cooler located at the top of the reactor, and the condensed organic solvents were delivered to the organic solvent storage unit and temporarily stored. The temporarily stored organic solvents were delivered to the stirring unit through a pipe fluidly connected between the organic solvent storage unit and the stirring unit for mixing with the anode scrap.

[0186] Organic solvent mixed black powder ① Type ② Mixing amount ③ Method ④ Internal temperature ⑤ Purity ⑥ Carbon content Example 1 DMSO 500 mL Stirring 100 ± 10℃ About 96% About 1.1 wt% Example 2 TEP 500 mL Stirring 100 ± 10℃ About 97% About 0.8 wt% Example 3 TEP 50 mL Stirring 100 ± 10℃ About 91% About 1.9 wt% Example 4 TEP 2,000 mL Stirring 100 ± 10℃ About 88% About 3.1 wt% Example 5 TEP 500 mL Stirring 20 ± 10℃ About 87% About 3.6 wt% Comparative example 1 TEP 500 mL Stirring 180 ± 10℃ About 86% About 3.3 wt% Comparative example 2 TEP 500 mL Ultrasonic irradiation 100 ± 10℃ About 82% About 4.8 wt% Comparative Example 3 NMP 500 mL Stirring 100±10℃ About 84% About 4.1 wt% Comparative Example 4 Water 500 mL Stirring 100±10℃ About 81% About 5.1 wt% DMSO: Dimethyl sulfoxide TEP: Triethyl phosphate NMP: N-methylpyrrolidone

[0187] Black powder mixing amount [based on total weight of water] Suspension additive Final black powder mixing amount [based on total volume of water] Type ⑦ Purity ⑧ Carbon content Example 2-a 0.05 wt% 0.5 vol% TEP About 97.1% About 0.7 wt% Example 2-b 30 wt% 0.5 vol% TEP About 98.0% About 0.4 wt% Example 2-c 60 wt% 0.5 vol% TEP About 96.9% About 0.8 wt% Example 2-d 0.5 wt% 0.05 vol% TEP About 97.1% About 0.7 wt% Example 2-e 0.5 wt% 0.5 vol% TEP About 98.8% About 0.1 wt% Example 2-f 0.5 wt% 10 vol% TEP About 98.4% About 0.2 wt% Example 2-g 0.5 %Wt 45%Volume %TEP About 96.6% About 0.6%Wt Example 2-h0.5 %Wt 0.6%Volume %Mineral oil About 98.3% About 0.3%Wt Example 2-i0.5 %Wt 30%Volume %Mineral oil About 98.5% About 0.1%Wt Example 2-j0.5 %Wt 40%Volume %Mineral oil About 97.2% About 0.7%Wt

[0188]

[0189] As shown in Table 1 and Table 2 above, it can be seen that the black powder manufacturing method according to the present invention can obtain high-purity black powder from positive electrode scrap with a high recovery rate.

[0190] From these results, it can be seen that the method and system for manufacturing black powder according to the present invention not only can manufacture high-purity black powder with high efficiency, but is also environmentally friendly because the organic solvent used during the process is reused.

[0191]

[0192] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art or having ordinary knowledge in the art that the present invention can be variously modified and changed within a scope that does not depart from the technical scope of the present invention as set forth in the claims to be described below.

[0193] Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the patent claims.

Claims

1. A method for producing black powder from positive electrode scrap derived from a waste battery, Step (S1) of stirring a mixture of positive electrode scrap and an organic solvent at a temperature of 150°C or lower to detach the positive electrode collector contained in the positive electrode scrap and to elute the conductive material and binder contained inside the black powder with an organic solvent. Step (S2) of filtering the above mixture to separate the positive electrode collector; Step (S3) of obtaining a black powder by separating an organic solvent containing a conductive agent and a binder from the above mixture from which the positive electrode collector is separated, and A step (S4) of separating the conductive material and the binder from the organic solvent containing the conductive material and the binder and recovering the organic solvent; The organic solvent recovered in the above step (S4) is reused in at least one of the steps (S1) to (S3); A method for producing black powder, wherein the organic solvent comprises at least one of trimethyl phosphate (TMP), triethyl phosphate (TEP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO).

2. In paragraph 1, A method for producing black powder in which the above cathode scrap is mixed with 200 mL to 900 mL of an organic solvent per 100 g.

3. In paragraph 1, The above step (S1) is a method for manufacturing black powder, which is performed under conditions of 200 rpm to 1,000 rpm for 5 to 100 minutes.

4. In paragraph 1, The step (S3) of obtaining the above black powder is: Step (S3-1) of centrifuging the mixture from which the positive electrode collector is separated; A step (S3-2) of separating an organic solvent containing a conductive agent and a binder by decanting the supernatant of the centrifuged mixture; It includes a step (S3-3) of filtering and washing the decanted residue to produce black powder. A method for producing black powder, wherein washing of the residue is performed twice or more repeatedly with the same organic solvent as the organic solvent of the mixture.

5. In paragraph 1, After the step (S3) of obtaining the above black powder, a step (S5) of further separating the conductive material included in the obtained black powder is further included. A method for producing black powder, wherein the above additional separation is performed through a flotation selection method.

6. In paragraph 5, The step (S5) of further separating the above challenge material is A step (S5-1) of mixing black powder and a floating additive in a hydrophilic solvent to float the conductive agent in the black powder to the top of the solution, and A method for manufacturing black powder, comprising a step (S5-2) of removing a conductive agent floating on the top of a solution.

7. In paragraph 5, The above black powder is mixed in an amount of 0.1 wt% to 50 wt% based on the weight of the hydrophilic solvent, A method for producing black powder, wherein the above floating additive is mixed in an amount of 0.1 to 40 volume% based on the volume of the hydrophilic solvent.

8. In paragraph 5, The above hydrophilic solvents are water and C 1~4 Containing at least one type of alkyl alcohol, A method for producing black powder, wherein the above floating additive comprises at least one of mineral oil, trimethyl phosphate (TMP), and triethyl phosphate (TEP).

9. In paragraph 1, A method for producing black powder, wherein the step (S4) of recovering the organic solvent is performed by distilling the organic solvent containing the conductive agent and the binder under reduced pressure.

10. In paragraph 1, A method for manufacturing black powder, characterized in that the manufactured black powder has a carbon element content of less than 5 wt% when analyzed by components.

11. In a system for manufacturing black powder from positive electrode scrap derived from waste batteries, A stirring section that stirs a mixture of positive electrode scrap and an organic solvent to detach the positive electrode collector contained in the positive electrode scrap and elute the conductive material and binder contained inside the black powder into the organic solvent. A filter unit that is fluidly connected to the above stirring unit and receives a stirred mixture, and filters out the positive electrode current collector from the provided mixture; A separation unit that is fluidly connected to the above filter unit and receives a separated mixture from the positive electrode collector, and separates an organic solvent containing a conductive agent and a binder from the provided mixture to obtain a black powder; and A distillation unit is included for separating the conductive agent and binder from the organic solvent separated in the above separation unit and recovering the organic solvent; The organic solvent recovered from the distillation unit is supplied to at least one of the stirring unit, the filtration unit, and the separation unit and reused; A black powder manufacturing system wherein the organic solvent comprises at least one of trimethyl phosphate (TMP), triethyl phosphate (TEP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl sulfoxide (DMSO).

12. In paragraph 11, The above separation unit is a black powder manufacturing system including a centrifuge.

13. In paragraph 11, The above black powder manufacturing system is a black powder manufacturing system further including a flotation separation unit that is fluidly connected to a separation unit to receive black powder and performs flotation separation to further remove a conductive material from the provided black powder.

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