Method for recycling waste battery materials based on plasma chemical vapor deposition technology

Abstract

This invention belongs to the field of waste battery material recycling and provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. First, a network complex with metal chelating function is synthesized, which forms a stable bond with the active sites on the electrode surface during subsequent coating deposition, effectively capturing harmful metal ions. Second, a fluorinated imidazole-quaternary ammonium salt network complex is designed, with fluorinated groups endowing it with excellent surface passivation and chemical stability. The stripping process, through periodic temperature adjustment and the combination of plasma technology, separates the active material from the metal current collector. The stripped active powder can be further extracted and purified by acid washing. The deposition process of the metal current collector combined with the fluorinated complex and inorganic silicon-oxygen network endows the metal surface with good corrosion resistance and reprocessing performance, making it suitable for the recycling of electrode materials from waste batteries and enhancing the reuse value of related materials.

Description

Technical Field

[0001] This invention belongs to the field of waste battery material recycling, and relates to a waste battery material recycling method based on plasma chemical vapor deposition technology. Background Technology

[0002] Traditional waste battery recycling faces several drawbacks and challenges. First, the complex, multi-layered structure of waste batteries (such as positive and negative electrodes, electrolyte, and separator) makes material separation and extraction extremely difficult. Mechanical methods easily lead to material contamination, while hydrometallurgical and pyrometallurgical processes, although capable of extracting valuable metals, are accompanied by high energy consumption, resource waste, and environmental pollution. The use of strong acids and alkalis in hydrometallurgical processes generates large amounts of acidic and alkaline waste liquids and heavy metal pollutants, and the purity and efficiency of separated metals are limited. Pyrometallurgical processes require high temperatures, consume enormous amounts of energy, and may release toxic gases (such as fluorides and organic decomposition products), causing secondary pollution. Furthermore, traditional recycling technologies struggle to effectively handle low-content metals like lithium and directly damage the current collector materials in waste batteries, further reducing resource recovery rates. Additionally, waste batteries pose a risk of thermal runaway during transportation and processing, further increasing safety challenges. Economically, traditional recycling processes are complex and costly, making it difficult to meet the demands of large-scale green recycling.

[0003] Plasma vapor deposition (PVD) technology has demonstrated significant advantages in the recycling of spent batteries. PVD can operate at low temperatures, avoiding material degradation caused by high-temperature processes. Furthermore, it can achieve interface control through the deposition of functional coatings (such as anti-corrosion layers or weak bonding layers), thereby promoting efficient separation of positive and negative electrode materials from the substrate. PVD can also provide protective coatings or functional modifications to recycled materials, such as depositing carbon coatings or oxide films on the surface of recycled positive electrode materials to improve their electrochemical performance and cycle stability. In addition, PVD can be used to treat hazardous substances in spent batteries, such as fixing or neutralizing toxic components (such as hydrogen fluoride) in the electrolyte by depositing fluoride adsorption layers, reducing environmental pollution. Compared to traditional wet and pyrometallurgical processes, PVD uses gaseous precursors as raw materials, does not require acid or alkali reagents, reduces the generation of liquid waste, and is a more environmentally friendly process. Therefore, developing a method for recycling spent battery materials based on plasma chemical vapor deposition technology is of great significance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention aims to provide a method for recycling waste battery materials based on plasma chemical vapor deposition (PCVD). First, a synthesized metal chelate network composite is deposited on the surface of the electrode material to capture metal ions through chemical bonding and form a weakly bound layer, providing a basis for interface control during subsequent stripping. Subsequently, the active material and the metal current collector are stripped through periodic changes in temperature and pulsed plasma. The stripped powder is then acid-washed to extract high-value metal salts. For the stripped metal current collector, this invention achieves surface passivation, protection, and functional modification through multilayer deposition of a fluoroimidazolium-quaternary ammonium salt composite and a silicon-oxygen network coating. The coating includes a impurity trapping layer and an inorganic protective layer, which improves the corrosion resistance and reusability of the metal material, thereby meeting the needs of practical production.

[0005] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology, comprising: S1, 1,3-bis(aminopropyl)tetramethyldisiloxane, 3-mercaptopropyltrimethoxysilane, pentafluorophenyltrimethoxysilane, triethylamine and deionized water are dispersed in anhydrous ethanol and reacted to obtain a metal chelating functional network complex. S2, glycidyl methacrylate, NaOH and deionized water are mixed to obtain pre-hydrolyzed glyceryl methacrylate, pre-hydrolyzed glyceryl methacrylate, 1-allyl-3-chloromethylimidazolium, methacryloyloxyethyltrimethylammonium chloride and hexafluorobutyl acrylate are dispersed in an ethanol aqueous solution, azobisisobutyramidine hydrochloride and NaOH are added, and the reaction is carried out to obtain an imidazolium-quaternary ammonium salt fluorinated complex network; S3, place the dried electrode sheet in the first chamber. In the first stage, use argon / hydrogen to clean the surface of the electrode sheet. Transfer the cleaned electrode sheet to the second chamber. In the second stage, introduce helium, heat and atomize trifluoropropyltrimethoxysilane and ultrasonically atomize metal chelate functional network complex solution. After two-step deposition, product A is obtained. S4, product A is transferred to the third chamber. In the third stage, the temperature of the chamber is periodically adjusted to carry out the peeling process, and the peeled active powder and Cu / Al current collector are obtained. In step S5, the Cu / Al current collector is placed in the fourth chamber. In the fourth stage, trifluoropropyltrimethoxysilane and ultrasonically atomized imidazole-quaternary ammonium salt fluorine-containing complex network solution are introduced to deposit the impurity trapping layer. In the fifth stage, trifluoropropyltrimethoxysilane, atomized tetraethoxysilane and water vapor are introduced to deposit the inorganic protective layer, thus obtaining a recyclable Cu / Al current collector.

[0006] Specifically, it includes: S1, 1,3-bis(aminopropyl)tetramethyldisiloxane, 3-mercaptopropyltrimethoxysilane, pentafluorophenyltrimethoxysilane, triethylamine and deionized water were dispersed in anhydrous ethanol, stirred at room temperature under a nitrogen atmosphere, the temperature was adjusted to the first temperature and stirred to react, after the reaction was completed, the mixture was rotary evaporated and dried to obtain the metal chelate functional network complex. S2, glycidyl methacrylate, NaOH and deionized water are mixed and heated to a second temperature with stirring to obtain pre-hydrolyzed glyceryl methacrylate. Pre-hydrolyzed glyceryl methacrylate, 1-allyl-3-chloromethylimidazolium, methacryloyloxyethyltrimethylammonium chloride and hexafluorobutyl acrylate are dispersed in an ethanol aqueous solution, pH is adjusted to 8, temperature is adjusted to a third temperature, azobisisobutyramidine hydrochloride is added and the reaction is stirred, NaOH is added and stirring is continued, after the reaction is completed, rotary evaporation and drying are used to obtain an imidazolium-quaternary ammonium salt fluorinated complex network; S3, the dried electrode sheet is placed in the first chamber. In the first stage, the chamber temperature is adjusted to the third temperature, and the surface of the electrode sheet is cleaned with argon and hydrogen in sequence. The cleaned electrode sheet is then transferred to the second chamber. In the second stage, the chamber temperature is adjusted to the fourth temperature, and hexamethyldisiloxane is heated to the second temperature and atomized before being introduced into the second chamber. Helium, heated and atomized trifluoropropyltrimethoxysilane, and ultrasonically atomized metal chelate functional network complex solution are then introduced. After two-step deposition, product A is obtained. S4, transfer product A to the third chamber. In the third stage, adjust the initial temperature of the chamber to 50°C and periodically raise it to 80°C and then lower it to 60°C. While controlling the temperature, perform the peeling process to obtain the peeled active powder and Cu / Al current collector. Disperse the peeled active powder in a dilute acid solution to obtain a metal salt mixture that can be used for extraction and purification. In step S5, the Cu / Al current collector is placed in the fourth chamber. In the fourth stage, the chamber temperature is adjusted to the fifth temperature, and trifluoropropyltrimethoxysilane and ultrasonically atomized imidazole-quaternary ammonium salt fluorine-containing complex network solution are introduced to deposit the impurity trapping layer. In the fifth stage, after the impurity trapping layer deposition is completed, O2 plasma is used for treatment, and trifluoropropyltrimethoxysilane, atomized tetraethoxysilane and water vapor are introduced to deposit the inorganic protective layer, thus obtaining a recyclable Cu / Al current collector.

[0007] In this invention, three siloxane compounds—1,3-bis(aminopropyl)tetramethyldisiloxane, 3-mercaptopropyltrimethoxysilane, and pentafluorophenyltrimethoxysilane—are used as the main reactant monomers. These compounds share the common characteristic of containing hydrolyzable methoxy groups. When the methoxy group comes into contact with water, it undergoes hydrolysis in the presence of triethylamine to generate silanol. Silanol is a highly reactive intermediate that can further form silicon-oxygen bonds through condensation reactions. Firstly, 1,3-bis(aminopropyl)tetramethyldisiloxane is the basic structural unit in the reaction system, providing not only the basic framework of silicon-oxygen bonds but also introducing metal chelating functionality through its amino groups. Amino groups are typical electron donors; their lone pairs of electrons can form coordinate bonds with metal ions, thereby achieving metal capture and chelation. Furthermore, the two amino groups in the molecule provide multiple active sites in the silicon-oxygen network, further enhancing the chelating function. Secondly, 3-mercaptopropyltrimethoxysilane introduces thiol groups, which are highly nucleophilic functional groups capable of forming strong chemical bonds with transition metal ions. The binding mechanism between thiols and metal ions typically involves the sulfur atom in the thiol group donating a lone pair of electrons to form a coordinate bond with the empty orbital of the metal ion. This effect makes the composite exhibit higher selectivity and efficiency in metal ion capture. Pentafluorophenyltrimethoxysilane, through its pentafluorophenyl group, endows the composite network with unique hydrophobicity and chemical stability. Pentafluorophenyl is a strong electron-attracting group, and its electronegativity helps reduce the polarity of the material surface, thereby increasing the network's resistance to chemical corrosion. This is crucial for using the material in complex chemical environments, as the hydrophobic surface reduces interactions with water molecules or other polar chemicals, extending the material's lifespan. After the hydrolysis reaction is complete, heating is used to promote the condensation reaction between silanols. The condensation reaction generates siloxane bonds through dehydration between silanols or alcoholysis between silanols and unhydrolyzed methoxy groups. After the reaction is complete, a stable solid metal chelating functional network complex is obtained, with a large number of amino and thiol groups exposed on its surface, which can be used to efficiently capture metal ions.

[0008] When glycidyl methacrylate is mixed with deionized water and heated under alkaline conditions, it undergoes a ring-opening reaction of an epoxy group, leading to the formation of an ester bond. Glycidyl methacrylate is a structurally bifunctional compound containing an epoxy group and an ester group of acrylic acid. The epoxy group is a three-membered ring structure. Due to the deviation of the COC bond angle within the ring from the normal bond angle, this structure exhibits high strain and chemical reactivity, readily undergoing ring-opening reactions under the action of nucleophiles or acidic / basic catalysts. Sodium hydroxide provides a highly nucleophilic hydroxyl ion. This hydroxyl ion acts as a nucleophile, attacking one carbon atom in the epoxy group. The carbon atom in the epoxy group, due to its connection to an electronegative oxygen atom, has a relatively low electron cloud density and exhibits electrophilicity, thus making it susceptible to nucleophilic attack. When the hydroxyl ion attacks the epoxy group, the epoxy three-membered ring breaks, generating an intermediate containing a hydroxyl group. Simultaneously, the original carboxyl group of the methacrylic acid molecule undergoes partial deprotonation under alkaline conditions, generating a carboxylate ion. The hydroxyl group generated from the ring-opening reacts with the carboxylate ion through intramolecular or intermolecular reactions, undergoing nucleophilic substitution to form a new ester bond, making it a preferred chemical target for breakage during subsequent plasma treatment. Pre-hydrolyzed glycidyl methacrylate, along with other monomers including 1-allyl-3-chloromethylimidazolium, methacryloyloxyethyltrimethylammonium chloride, and hexafluorobutyl acrylate, is dispersed in an ethanol-water mixture. The pH of the solution is adjusted to 8, and then azobisisobutyramidine hydrochloride is added as a free radical initiator to initiate the polymerization reaction. The core mechanism of free radical polymerization is the generation of active free radicals through the decomposition of the initiator, which induces ring-opening polymerization of the monomer's double bonds. Upon heating, these free radicals decompose to generate two free radical centers, which can attack the double bonds in the monomer molecule, initiating a chain polymerization reaction. In this process, each monomer molecule participating in polymerization generates a new free radical, which continues to attack the double bonds of other monomer molecules, thus forming a long-chain polymer. In this reaction system, the combined action of various monomers determines the final polymer's chemical properties and structural function. 1-Allyl-3-chloromethylimidazolium is a key monomer, whose imidazole group possesses a unique ion-exchange function. As a quaternary ammonium salt cation, the imidazole group can capture negatively charged metal ions or other ionic compounds through electrostatic interactions.

[0009] The function of methacryloyloxyethyltrimethylammonium chloride is similar to that of 1-allyl-3-chloromethylimidazolium, but its quaternary ammonium salt structure is simpler and more stable. Its trimethylammonium chloride group enhances the cation density of the entire system, thereby improving the polymer's ability to capture negatively charged ions. Hexafluorobutyl acrylate provides the polymer with hydrophobicity and chemical stability. Due to its high electronegativity and large size, the fluorine atom in hexafluorobutyl acrylate significantly reduces the surface energy of the polymer, thus giving it excellent hydrophobic properties. Furthermore, the introduction of fluorine atoms improves the polymer's resistance to oxidation and chemical corrosion, allowing it to remain stable under harsh conditions. Ultimately, a network of imidazolium-quaternary ammonium salt fluorinated complexes with special chemical functions is obtained. This network possesses both high cation density and excellent ion-capturing ability, and its chemical stability and hydrophobicity are enhanced by the introduction of fluorinated groups, enabling it to maintain long-term stability in complex chemical environments.

[0010] First, the dried electrode sheet is placed in the first chamber, where surface cleaning provides a clean and activated substrate surface for subsequent deposition. An argon / hydrogen mixture is introduced into the chamber for cleaning. Argon, an inert gas, is excited and accelerated in a plasma state, generating high-energy argon ions. These ions bombard the electrode sheet surface with kinetic energy. The argon ion bombardment physically removes weakly bound contaminants such as thin oxide layers, dust particles, or residual organic matter. In this process, argon cleaning is not merely a physical stripping process; it also microscales the energy distribution on the electrode sheet surface, enhancing its chemical activity by introducing local defects or free radicals. This surface modification provides more active sites for the chemical bonding of the subsequently deposited coating. Hydrogen is decomposed into highly reactive hydrogen atoms under plasma conditions. These hydrogen atoms can efficiently react with residual oxides or organic molecules on the electrode sheet surface. Oxide reduction is crucial in this stage because a thin layer of metal oxide may exist on the electrode sheet surface, which reduces surface conductivity and coating adhesion. Through the chemical reduction of hydrogen atoms, the oxide layer is transformed into more stable volatile products, thereby further improving the cleanliness of the surface.

[0011] After cleaning, the electrode sheet is transferred to a second chamber for a two-step coating deposition. First, hexamethyldisiloxane is used as a precursor. Hexamethyldisiloxane is heated and atomized, mixed with helium, and then introduced into the chamber. The atomized hexamethyldisiloxane molecules are excited, adsorbed onto the electrode surface, and undergo a chemical reaction, gradually forming a cross-linked silicon-oxygen network. The formation of this network is achieved through a condensation reaction. This cross-linked structure not only possesses excellent mechanical strength but also exhibits extremely high chemical stability. The main function of the underlayer coating is to provide a robust base layer, protecting the electrode sheet from chemical corrosion in subsequent operations, while also providing structural support for the adhesion of the upper coating. The second deposition step involves the construction of a functionalized coating. This stage introduces a solution of trifluoropropyltrimethoxysilane and a metal-chelated functional network complex. Trifluoropropyltrimethoxysilane is heated and atomized before entering the chamber, reacting with the surface of the underlayer coating to form a functionalized coating. The trifluoropropyl groups further enhance the overall performance of the coating through their hydrophobicity and chemical stability, making it resistant to chemical corrosion from the external environment. Simultaneously, the trimethoxysilane groups bond with the underlying coating through chemical bonds, achieving robust adhesion between the multilayer coatings. The active groups in the metal chelating functional network composite are embedded in the coating structure during deposition, capturing metal ions through their highly selective chemical coordination ability and locking these ions by forming stable chelate bonds.

[0012] Product A was transferred to the third chamber for the exfoliation of the functional coating and the recovery of the active powder. The exfoliation process employed a periodic temperature control strategy, with the initial chamber temperature set at 50°C, followed by periodic increases to 80°C and then decreases to 60°C during the exfoliation process. This periodic temperature variation was designed to introduce interfacial stress by utilizing the difference in thermal expansion coefficients between the coating and the substrate. When the temperature rose to 80°C, thermal stress was generated between the coating and substrate materials due to the difference in their expansion coefficients. This stress concentrated at the interface between the coating and the substrate, gradually weakening the adhesion between them. Subsequently, the temperature was lowered to 60°C, and the shrinkage behavior of the coating and the substrate further accumulated and released the interfacial stress. Through multiple cycles, this thermal stress gradually destroyed the interfacial adhesion between the coating and the substrate, ultimately causing the coating to detach from the substrate material. To further assist the exfoliation process, the plasma power was periodically controlled. At the start of the peeling process, the instantaneous peak power was set to 300W. This high-power stage further weakened the interfacial adhesion between the coating and the substrate through the direct bombardment of high-energy particles. At the same time, it may induce the propagation of micro-cracks in the coating, making the peeling of the coating easier. The peeled coating was eventually collected as active powder, while the substrate material (Cu / Al current collector) maintained a relatively complete structural state and could be used for subsequent recycling.

[0013] The stripped active powder is dispersed in a dilute acid solution for metal salt extraction. The dilute acid solution breaks the metal chelate bonds in the active powder through acidolysis, releasing metal ions from the chelate groups and into the solution. The chemical bonds between the chelate groups and the metal ions are protonated and broken in the acidic environment, while the metal ions combine with acid radicals in the solution to form a stable metal salt solution. This metal salt extraction process is not only highly efficient but also highly selective, capable of separating most of the metal components from the active powder. These metal salts can be used for subsequent separation and purification operations. Meanwhile, the Cu / Al current collector, which was not chemically eroded during the stripping process, is recovered as a solid product.

[0014] The stripped Cu / Al current collector was placed in the fourth chamber. The impurity trapping layer was deposited using trifluoropropyltrimethoxysilane and an ultrasonically atomized imidazolium-quaternary ammonium salt fluorinated complex network solution as precursors. This combination formed a functional coating on the current collector surface using plasma-assisted chemical vapor deposition (PACVD). The trimethoxysilane groups in trifluoropropyltrimethoxysilane undergo hydrolysis and condensation reactions at high temperatures, generating a silicon-oxygen cross-linked network that chemically bonds to the current collector surface. This silicon-oxygen network not only provides mechanical stability to the impurity trapping layer but also enhances the coating's corrosion resistance through the hydrophobicity and chemical inertness of the trifluoropropyl groups. Simultaneously, the added imidazolium-quaternary ammonium salt fluorinated complex network solution was transformed into uniform liquid droplets using ultrasonic atomization, participating in the deposition along with the trifluoropropyltrimethoxysilane. The imidazolium and quaternary ammonium salt groups in these complexes possess unique chemical activity, enabling them to trap impurity molecules (such as residual metal ions and organic contaminants) through electrostatic interactions or intermolecular forces. The introduction of fluorine further enhances the chemical stability of the coating, enabling it to maintain its performance in complex environments. Simultaneously, the molecular structure of this fluorine-containing composite exhibits excellent dispersibility and uniformity, allowing it to form a tightly bonded composite coating with the silicon-oxygen network during deposition. Finally, in the impurity trapping layer deposition stage, the current collector surface is coated with a functional coating that provides both mechanical strength and impurity trapping capabilities.

[0015] After the impurity trapping layer is deposited, O2 is introduced into the chamber for plasma treatment. This step further activates and chemically modifies the surface of the impurity trapping layer using high-energy oxygen plasma. The oxygen plasma, through the bombardment of its active oxygen atoms and ions, can remove any residual organic contaminants or unreacted precursor molecules from the coating surface, while simultaneously generating highly active functional groups on the coating surface. These surface-active sites provide the chemical bonding conditions for the subsequent deposition of the inorganic protective layer. Furthermore, the oxygen plasma can further improve the corrosion resistance and chemical stability of the impurity trapping layer through surface oxidation. Following the O2 plasma treatment, the inorganic protective layer is deposited. In this stage, trifluoropropyltrimethoxysilane, atomized tetraethoxysilane, and water vapor are simultaneously introduced to form a uniform inorganic protective coating on the surface of the impurity trapping layer. Trifluoropropyltrimethoxysilane is again introduced as a precursor, continuing to play its role in the cross-linking network. Tetraethoxysilane is the core component of the inorganic protective layer. It generates active siloxane groups that can form a dense silicon-oxygen cross-linked network through condensation reactions, chemically bonding with the surface of the impurity trapping layer to construct an inorganic protective layer. The main function of the inorganic protective layer is to provide long-term protection for the current collector. The dense structure of the silicon-oxygen network effectively prevents the penetration of corrosive gases or liquids, thereby extending the service life of the current collector. The presence of trifluoropropyl groups gives the inorganic protective layer good hydrophobicity and anti-fouling properties, further improving its practicality.

[0016] As a preferred embodiment of the present invention, in S1, the mass ratio of 1,3-bis(aminopropyl)tetramethyldisiloxane, 3-mercaptopropyltrimethoxysilane and pentafluorophenyltrimethoxysilane is 10:5:3.

[0017] In some alternative embodiments, the stirring time at room temperature is 1-2 hours, for example, 1 hour, 1.1 hours, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours, or 2 hours, but is not limited to the listed times; other unlisted times within this time range are also applicable.

[0018] In some alternative embodiments, the first temperature is 70-80°C, for example, it can be 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C or 80°C, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0019] In some alternative embodiments, the stirring reaction time is 4-5 hours, for example, 4 hours, 4.1 hours, 4.2 hours, 4.3 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.7 hours, 4.8 hours, 4.9 hours, or 5 hours, but is not limited to the listed times; other unlisted times within this time range are also applicable.

[0020] As a preferred embodiment of the present invention, in S2, the mass ratio of glycidyl methacrylate, 1-allyl-3-chloromethylimidazolium, methacryloyloxyethyltrimethylammonium chloride, hexafluorobutyl acrylate and azobisisobutyramidine hydrochloride is 2:5:8:3:0.2.

[0021] In some alternative embodiments, the second temperature is 60-70°C, for example, it can be 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0022] In some alternative embodiments, the stirring reaction time is 4-5 hours, for example, 4 hours, 4.1 hours, 4.2 hours, 4.3 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.7 hours, 4.8 hours, 4.9 hours, or 5 hours, but is not limited to the listed times; other unlisted times within this time range are also applicable.

[0023] In some alternative embodiments, the stirring time is 1-2 hours, for example, it can be 1 hour, 1.1 hours, 1.2 hours, 1.3 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours or 2 hours, but is not limited to the listed times, other unlisted times within this time range are also applicable.

[0024] As a preferred technical solution of the present invention, in S3, the first stage... In some alternative embodiments, the flow rate of the argon gas is 30-40 sccm, for example, it can be 30 sccm, 31 sccm, 32 sccm, 33 sccm, 34 sccm, 35 sccm, 36 sccm, 37 sccm, 38 sccm, 39 sccm or 40 sccm, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0025] In some alternative embodiments, the hydrogen flow rate is 20-30 sccm, for example, it can be 20 sccm, 21 sccm, 22 sccm, 23 sccm, 24 sccm, 25 sccm, 26 sccm, 27 sccm, 28 sccm, 29 sccm or 30 sccm, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0026] In some alternative embodiments, the radio frequency power of the argon / hydrogen gas is 150-170W, 150W, 152W, 154W, 156W, 158W, 160W, 162W, 164W, 166W, 168W, or 170W, but is not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0027] In some optional embodiments, the cleaning time is 7 minutes.

[0028] The second phase, In some alternative embodiments, the third temperature is 90-100°C, for example, it can be 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C or 100°C, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0029] In some alternative embodiments, the fourth temperature is 40-50°C, for example, it can be 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C or 50°C, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0030] In some alternative embodiments, the flow rate of the hexamethyldisiloxane is 10-20 sccm, for example, it can be 10 sccm, 11 sccm, 12 sccm, 13 sccm, 14 sccm, 15 sccm, 16 sccm, 17 sccm, 18 sccm, 19 sccm or 20 sccm, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0031] In some alternative embodiments, the flow rate of the helium gas is 150-170 sccm, for example, it can be 150 sccm, 152 sccm, 154 sccm, 156 sccm, 158 sccm, 160 sccm, 162 sccm, 164 sccm, 166 sccm, 168 sccm or 170 sccm, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0032] In some alternative embodiments, the flow rate of the heated and atomized trifluoropropyltrimethoxysilane is 5-8 sccm, for example, 5 sccm, 5.3 sccm, 5.6 sccm, 5.9 sccm, 6.2 sccm, 6.5 sccm, 6.8 sccm, 7.1 sccm, 7.4 sccm, 7.7 sccm or 8 sccm, but is not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0033] In some optional embodiments, the ultrasonically atomized metal chelate functional network complex solution has a mass fraction of 15 wt.% and the solvent is anhydrous ethanol.

[0034] In some alternative embodiments, the flow rate of the atomized metal chelate functional network complex solution is 0.2-0.5 sccm, for example, 0.2 sccm, 0.23 sccm, 0.26 sccm, 0.29 sccm, 0.32 sccm, 0.35 sccm, 0.38 sccm, 0.41 sccm, 0.44 sccm, 0.47 sccm or 0.5 sccm, but is not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0035] In some optional embodiments, the two deposition steps are as follows: Substrate deposition: RF power of 100-110W, for example, 100W, 101W, 102W, 103W, 104W, 105W, 106W, 107W, 108W, 109W, or 110W, for a time of 10-15 minutes, for example, 10 minutes, 10.5 minutes, 11 minutes, 11.5 minutes, 12 minutes, 12.5 minutes, 13 minutes, 13.5 minutes, 14 minutes, 14.5 minutes, or 15 minutes. Upper layer deposition: RF power 70-90W, for example, 70W, 72W, 74W, 76W, 78W, 80W, 82W, 84W, 86W, 88W or 90W, time 20-25min, for example, 20min, 20.5min, 21min, 21.5min, 22min, 22.5min, 23min, 23.5min, 24min, 24.5min or 25min, but not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0036] In some alternative embodiments, the periodic temperature adjustment involves adjusting the initial temperature of the chamber to 50°C and periodically raising it to 80°C and then lowering it to 60°C.

[0037] As a preferred technical solution of the present invention, in S4, the third stage... In some optional embodiments, the heating rate is 10°C / min.

[0038] In some optional embodiments, the cooling rate is 10°C / min.

[0039] In some optional embodiments, the stripping process involves setting the instantaneous peak power to 300-320W, for example, 300W, 302W, 304W, 306W, 308W, 310W, 312W, 314W, 316W, 318W, or 320W, for a duration of 12-15 seconds, for example, 12s, 12.3s, 12.6s, 12.9s, 13.2s, 13.5s, 13.8s, 14.1s, 14.4s, 14.7s, or 15s, and then switching to 50-60W, for example, 50W, 51W, 52W, 53W, 54W, 55W, or 56W. Use 57W, 58W, 59W, or 60W, and maintain for 20-25 seconds, for example, 20s, 20.5s, 21s, 21.5s, 22s, 22.5s, 23s, 23.5s, 24s, 24.5s, or 25s. The total time for the stripping process is 15-18 minutes, for example, 15 minutes, 15.3 minutes, 15.6 minutes, 15.9 minutes, 16.2 minutes, 16.5 minutes, 16.8 minutes, 17.1 minutes, 17.4 minutes, 17.7 minutes, or 18 minutes. However, it is not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0040] In some optional embodiments, the dilute acid solution is 0.5M H2SO4.

[0041] As a preferred technical solution of the present invention, in S5, the fourth stage... In some optional embodiments, the fifth temperature is 130-150°C, for example, it can be 130°C, 132°C, 134°C, 136°C, 138°C, 140°C, 142°C, 144°C, 146°C, 148°C or 150°C, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0042] In some alternative embodiments, the flow rate of the trifluoropropyltrimethoxysilane is 10-20 sccm, for example, it can be 10 sccm, 11 sccm, 12 sccm, 13 sccm, 14 sccm, 15 sccm, 16 sccm, 17 sccm, 18 sccm, 19 sccm or 20 sccm, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0043] In some optional embodiments, the imidazole-quaternary ammonium salt fluorinated complex network solution has a mass fraction of 10 wt.% and the solvent is anhydrous ethanol.

[0044] In some alternative embodiments, the flow rate of the ultrasonically atomized metal chelate functional network complex solution is 0.3-0.7 sccm, for example, 0.3 sccm, 0.34 sccm, 0.38 sccm, 0.42 sccm, 0.46 sccm, 0.5 sccm, 0.54 sccm, 0.58 sccm, 0.62 sccm, 0.66 sccm or 0.7 sccm, but is not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0045] In some optional embodiments, the conditions for depositing the impurity trap layer are as follows: power of 100-120W, for example, 100W, 102W, 104W, 106W, 108W, 110W, 112W, 114W, 116W, 118W or 120W; deposition time of 10-15min, for example, 10min, 10.5min, 11min, 11.5min, 12min, 12.5min, 13min, 13.5min, 14min, 14.5min or 15min; and chamber temperature of 150°C, but not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0046] Phase 5 In some alternative embodiments, the flow rate of the trifluoropropyltrimethoxysilane is 5-8 sccm, 5 sccm, 5.3 sccm, 5.6 sccm, 5.9 sccm, 6.2 sccm, 6.5 sccm, 6.8 sccm, 7.1 sccm, 7.4 sccm, 7.7 sccm or 8 sccm, but is not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0047] In some alternative embodiments, the flow rate of the atomized tetraethoxysilane is 3-6 sccm, for example, it can be 3 sccm, 3.3 sccm, 3.6 sccm, 3.9 sccm, 4.2 sccm, 4.5 sccm, 4.8 sccm, 5.1 sccm, 5.4 sccm, 5.7 sccm or 6 sccm, but is not limited to the listed values, other unlisted values ​​within this temperature range are also applicable.

[0048] In some alternative embodiments, the flow rate of the water vapor is 0.2-0.5 sccm.

[0049] In some optional embodiments, the conditions for depositing the inorganic protective layer are as follows: power of 200-220W, for example, 200W, 202W, 204W, 206W, 208W, 210W, 212W, 214W, 216W, 218W, or 220W; deposition time of 10-12 min, for example, 10 min, 10.2 min, 10.4 min, 10.6 min, 10.8 min, 11 min, 11.2 min, 11.4 min, 11.6 min, 11.8 min, or 12 min; and chamber temperature of 180°C, but not limited to the listed values; other unlisted values ​​within this temperature range are also applicable.

[0050] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) By forming stable coordination complexes with metal ions through thiol and amino ligands, residual metal impurities on the surface of electrode materials can be captured efficiently, improving separation efficiency and reducing the loss of metal ions; (2) By depositing a weak bonding layer on the surface of electrode materials, the design of the weak bonding layer reduces the energy requirement for material stripping, avoids damage to the electrode sheet by high temperature or strong mechanical force, and retains the physical properties of Cu / Al current collector and active powder relatively intact; (3) For the separated Cu / Al current collector, the strong metal capture ability of the fluorine-containing complex network is used to remove residual metal ions on the surface, improve the cleanliness of the current collector, and provide excellent corrosion resistance and chemical stability through the high-density network structure of silicon oxide, giving the current collector higher application value. Attached Figure Description

[0051] Figure 1 The flowcharts are for the waste battery material recycling methods based on plasma chemical vapor deposition technology provided in Embodiments 1-4 of the present invention. Detailed Implementation

[0052] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0053] The chemical reagents used in the embodiments and comparative examples of this invention are all commercially available products and have not undergone any further purification treatment.

[0054] Example 1

[0055] like Figure 1 As shown in the figure, this embodiment provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. The method specifically includes the following steps: S1, 10g of 1,3-bis(aminopropyl)tetramethyldisiloxane, 5g of 3-mercaptopropyltrimethoxysilane, 3g of pentafluorophenyltrimethoxysilane, 0.2mL of triethylamine and 0.5mL of deionized water were dispersed in 100mL of anhydrous ethanol. The mixture was stirred at room temperature for 1.3h under a nitrogen atmosphere. The temperature was then adjusted to 75℃ and stirred for 4.8h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain a metal chelate functional network complex. S2, 2g glycidyl methacrylate, 0.1g NaOH and 5mL deionized water were mixed and heated to 44℃ and stirred for 24min to obtain pre-hydrolyzed glyceryl methacrylate. Pre-hydrolyzed glyceryl methacrylate, 5g 1-allyl-3-chloromethylimidazolium, 8g methacryloyloxyethyltrimethylammonium chloride and 3g hexafluorobutyl acrylate were dispersed in 200mL ethanol aqueous solution, pH was adjusted to 8, temperature was adjusted to 66℃, 0.2g azobisisobutyramidine hydrochloride was added and the reaction was stirred for 4.2h, 0.5g NaOH was added and stirring was continued for 1.3h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain an imidazolium-quaternary ammonium salt fluorinated complex network. S3. Place the dried electrode sheet in the first chamber. In the first stage, adjust the chamber temperature to 66°C and clean the electrode sheet surface with argon / hydrogen gas. The flow rate of argon gas is 30 sccm, the flow rate of hydrogen gas is 20 sccm, the radio frequency power is 150W, and the cleaning time is 7 min. Transfer the cleaned electrode sheet to the second chamber. In the second stage, adjust the chamber temperature to 92°C. Heat hexamethyldisiloxane to 44°C and atomize it before introducing it into the second chamber. Introduce helium gas at a flow rate of 150 sccm, heated and atomized trifluoropropyltrimethoxysilane at a flow rate of 5 sccm, and ultrasonically atomized metal chelate functional network complex solution at a flow rate of 0.2 sccm. Perform two-step deposition. The bottom layer is deposited with a radio frequency power of 100W for 10 min, and the top layer is deposited with a radio frequency power of 70W for 20 min to obtain product A. S4, transfer product A to the third chamber. In the third stage, adjust the initial temperature of the chamber to 50℃ and periodically raise it to 80℃ and then lower it to 60℃. The heating rate is 10℃ / min and the cooling rate is 10℃ / min. The peeling process is carried out simultaneously with the temperature control. The instantaneous peak power of the peeling process is set to 300W for 12s, and then switched to 50W for 20s. The total peeling time is 15min. The peeled active powder and Cu / Al current collector are obtained. The peeled active powder is dispersed in 0.5M H2SO4 to obtain a metal salt mixture that can be used for extraction and purification. Table 1. Test results of waste battery material recycling using plasma chemical vapor deposition technology in Examples 1-4 and Comparative Examples 1-2 In step S5, the Cu / Al current collector is placed in the fourth chamber. In the fourth stage, the chamber temperature is adjusted to 138℃, and a network solution of trifluoropropyltrimethoxysilane with a flow rate of 10 sccm and ultrasonically atomized imidazole-quaternary ammonium salt fluorinated complex with a flow rate of 0.3 sccm is introduced to deposit a impurity trapping layer. The power is 100W, and the deposition time is 10 min. In the fifth stage, after the impurity trapping layer deposition is completed, O2 plasma treatment is performed. A layer of inorganic protective layer is deposited by introducing trifluoropropyltrimethoxysilane with a flow rate of 5 sccm, atomized tetraethoxysilane with a flow rate of 3 sccm, and water vapor with a flow rate of 0.2 sccm. The power is 200W, and the deposition time is 10 min, resulting in a recyclable Cu / Al current collector.

[0056] Example 2

[0057] like Figure 1 As shown in the figure, this embodiment provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. The method specifically includes the following steps: S1, 10g of 1,3-bis(aminopropyl)tetramethyldisiloxane, 5g of 3-mercaptopropyltrimethoxysilane, 3g of pentafluorophenyltrimethoxysilane, 0.2mL of triethylamine and 0.5mL of deionized water were dispersed in 100mL of anhydrous ethanol. The mixture was stirred at room temperature for 1.0h under a nitrogen atmosphere. The temperature was then adjusted to 70℃ and stirred for 4.0h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain a metal chelate functional network complex. S2, 2g glycidyl methacrylate, 0.1g NaOH and 5mL deionized water were mixed and heated to 40℃ and stirred for 20min to obtain pre-hydrolyzed glyceryl methacrylate. Pre-hydrolyzed glyceryl methacrylate, 5g 1-allyl-3-chloromethylimidazolium, 8g methacryloyloxyethyltrimethylammonium chloride and 3g hexafluorobutyl acrylate were dispersed in 200mL ethanol aqueous solution, the pH was adjusted to 8, the temperature was adjusted to 60℃, 0.2g azobisisobutyramidine hydrochloride was added and the reaction was stirred for 4.0h, 0.5g NaOH was added and the stirring was continued for 1.6h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain an imidazolium-quaternary ammonium salt fluorinated complex network. S3, the dried electrode sheet is placed in the first chamber. In the first stage, the chamber temperature is adjusted to 60°C, and the surface of the electrode sheet is cleaned with argon / hydrogen gas. The flow rate of argon gas is 40 sccm, the flow rate of hydrogen gas is 30 sccm, the radio frequency power is 170W, and the cleaning time is 7min. The cleaned electrode sheet is then transferred to the second chamber. In the second stage, the chamber temperature is adjusted to 98°C, hexamethyldisiloxane is heated to 48°C and atomized, and then introduced into the second chamber. Helium gas with a flow rate of 170 sccm, heated and atomized trifluoropropyltrimethoxysilane with a flow rate of 8 sccm, and ultrasonically atomized metal chelate functional network complex solution with a flow rate of 0.5 sccm are introduced. Two-step deposition is performed: the bottom layer is deposited with a radio frequency power of 110W for 15min, and the top layer is deposited with a radio frequency power of 90W for 25min to obtain product A. S4, transfer product A to the third chamber. In the third stage, adjust the initial temperature of the chamber to 50℃ and periodically raise it to 80℃ and then lower it to 60℃. The heating rate is 10℃ / min and the cooling rate is 10℃ / min. The peeling process is carried out simultaneously with the temperature control. The instantaneous peak power of the peeling process is set to 320W for 15s, and then switched to 60W for 25s. The total peeling time is 18min. The peeled active powder and Cu / Al current collector are obtained. The peeled active powder is dispersed in 0.5M H2SO4 to obtain a metal salt mixture that can be used for extraction and purification. In step S5, the Cu / Al current collector is placed in the fourth chamber. In the fourth stage, the chamber temperature is adjusted to 130℃, and a network solution of trifluoropropyltrimethoxysilane with a flow rate of 20 sccm and ultrasonically atomized imidazole-quaternary ammonium salt fluorinated complex with a flow rate of 0.7 sccm is introduced to deposit a impurity trapping layer. The power is 120W, and the deposition time is 15 min. In the fifth stage, after the impurity trapping layer deposition is completed, O2 plasma treatment is performed. A layer of inorganic protective layer is deposited by introducing trifluoropropyltrimethoxysilane with a flow rate of 5 sccm, atomized tetraethoxysilane with a flow rate of 3 sccm, and water vapor with a flow rate of 0.2 sccm. The power is 220W, and the deposition time is 12 min, resulting in a recyclable Cu / Al current collector.

[0058] Example 3

[0059] like Figure 1 As shown in the figure, this embodiment provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. The method specifically includes the following steps: S1, 10g of 1,3-bis(aminopropyl)tetramethyldisiloxane, 5g of 3-mercaptopropyltrimethoxysilane, 3g of pentafluorophenyltrimethoxysilane, 0.2mL of triethylamine and 0.5mL of deionized water were dispersed in 100mL of anhydrous ethanol. The mixture was stirred at room temperature for 1.6h under a nitrogen atmosphere. The temperature was then adjusted to 80℃ and stirred for 4.5h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain a metal chelate functional network complex. S2, 2g glycidyl methacrylate, 0.1g NaOH and 5mL deionized water were mixed and heated to 48℃ and stirred for 27min to obtain pre-hydrolyzed glyceryl methacrylate. Pre-hydrolyzed glyceryl methacrylate, 5g 1-allyl-3-chloromethylimidazolium, 8g methacryloyloxyethyltrimethylammonium chloride and 3g hexafluorobutyl acrylate were dispersed in 200mL ethanol aqueous solution, the pH was adjusted to 8, the temperature was adjusted to 64℃, 0.2g azobisisobutyramidine hydrochloride was added and the reaction was stirred for 4.9h, 0.5g NaOH was added and the stirring was continued for 1.0h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain an imidazolium-quaternary ammonium salt fluorinated complex network. S3. Place the dried electrode sheet in the first chamber. In the first stage, adjust the chamber temperature to 70°C and clean the electrode sheet surface with argon / hydrogen gas. The flow rate of argon gas is 33 sccm, the flow rate of hydrogen gas is 25 sccm, the radio frequency power is 160W, and the cleaning time is 7min. Transfer the cleaned electrode sheet to the second chamber. In the second stage, adjust the chamber temperature to 90°C. Heat hexamethyldisiloxane to 40°C and atomize it before introducing it into the second chamber. Introduce helium gas at a flow rate of 160 sccm, heated and atomized trifluoropropyltrimethoxysilane at a flow rate of 6 sccm, and ultrasonically atomized metal chelate functional network complex solution at a flow rate of 0.4 sccm. Perform two-step deposition. The bottom layer is deposited with a radio frequency power of 104W for 13min, and the top layer is deposited with a radio frequency power of 80W for 23min to obtain product A. S4, transfer product A to the third chamber. In the third stage, adjust the initial temperature of the chamber to 50℃ and periodically raise it to 80℃ and then lower it to 60℃. The heating rate is 10℃ / min and the cooling rate is 10℃ / min. The peeling process is carried out simultaneously with the temperature control. The instantaneous peak power of the peeling process is set to 310W for 13s, and then switched to 55W for 23s. The total peeling time is 17min. The peeled active powder and Cu / Al current collector are obtained. The peeled active powder is dispersed in 0.5M H2SO4 to obtain a metal salt mixture that can be used for extraction and purification. In step S5, the Cu / Al current collector is placed in the fourth chamber. In the fourth stage, the chamber temperature is adjusted to 142℃, and a network solution of trifluoropropyltrimethoxysilane with a flow rate of 16 sccm and ultrasonically atomized imidazole-quaternary ammonium salt fluorinated complex with a flow rate of 0.5 sccm is introduced to deposit a impurity trapping layer. The power is 110W, and the deposition time is 12 min. In the fifth stage, after the impurity trapping layer deposition is completed, O2 plasma treatment is performed. A layer of inorganic protective layer is deposited by introducing trifluoropropyltrimethoxysilane with a flow rate of 6 sccm, atomized tetraethoxysilane with a flow rate of 4 sccm, and water vapor with a flow rate of 0.4 sccm. The power is 210W, and the deposition time is 11 min, resulting in a recyclable Cu / Al current collector.

[0060] Example 4

[0061] like Figure 1 As shown in the figure, this embodiment provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. The method specifically includes the following steps: S1, 10g of 1,3-bis(aminopropyl)tetramethyldisiloxane, 5g of 3-mercaptopropyltrimethoxysilane, 3g of pentafluorophenyltrimethoxysilane, 0.2mL of triethylamine and 0.5mL of deionized water were dispersed in 100mL of anhydrous ethanol. The mixture was stirred at room temperature for 2.0h under a nitrogen atmosphere. The temperature was then adjusted to 73℃ and stirred for 5.0h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain a metal chelate functional network complex. S2, 2g glycidyl methacrylate, 0.1g NaOH and 5mL deionized water were mixed and heated to 50℃ and stirred for 30min to obtain pre-hydrolyzed glyceryl methacrylate. Pre-hydrolyzed glyceryl methacrylate, 5g 1-allyl-3-chloromethylimidazolium, 8g methacryloyloxyethyltrimethylammonium chloride and 3g hexafluorobutyl acrylate were dispersed in 200mL ethanol aqueous solution, the pH was adjusted to 8, the temperature was adjusted to 70℃, 0.2g azobisisobutyramidine hydrochloride was added and the reaction was stirred for 5.0h, 0.5g NaOH was added and the stirring was continued for 2.0h. After the reaction was completed, the mixture was rotary evaporated and dried to obtain an imidazolium-quaternary ammonium salt fluorinated complex network. S3. Place the dried electrode sheet in the first chamber. In the first stage, adjust the chamber temperature to 62°C and clean the electrode sheet surface with argon / hydrogen gas. The flow rate of argon gas is 38 sccm, the flow rate of hydrogen gas is 23 sccm, the radio frequency power is 165W, and the cleaning time is 7 min. Transfer the cleaned electrode sheet to the second chamber. In the second stage, adjust the chamber temperature to 100°C, heat hexamethyldisiloxane to 50°C and atomize it, then introduce it into the second chamber. Introduce helium gas at a flow rate of 155 sccm, heated and atomized trifluoropropyltrimethoxysilane at a flow rate of 7 sccm, and ultrasonically atomized metal chelate functional network complex solution at a flow rate of 0.3 sccm. Perform two-step deposition. The bottom layer is deposited with a radio frequency power of 103W for 12.5 min, and the top layer is deposited with a radio frequency power of 75W for 24 min to obtain product A. S4, transfer product A to the third chamber. In the third stage, adjust the initial temperature of the chamber to 50℃ and periodically raise it to 80℃ and then lower it to 60℃. The heating rate is 10℃ / min and the cooling rate is 10℃ / min. The peeling process is carried out simultaneously with the temperature control. The instantaneous peak power of the peeling process is set to 305W for 13s, and then switched to 53W for 21s. The total peeling time is 16min. The peeled active powder and Cu / Al current collector are obtained. The peeled active powder is dispersed in 0.5M H2SO4 to obtain a metal salt mixture that can be used for extraction and purification. In step S5, the Cu / Al current collector is placed in the fourth chamber. In the fourth stage, the chamber temperature is adjusted to 150°C, and a network solution of trifluoropropyltrimethoxysilane with a flow rate of 14 sccm and ultrasonically atomized imidazole-quaternary ammonium salt fluorinated complex with a flow rate of 0.4 sccm is introduced to deposit a impurity trapping layer. The power is 115 W, and the deposition time is 14 min. In the fifth stage, after the impurity trapping layer deposition is completed, O2 plasma treatment is performed. A layer of inorganic protective layer is deposited by introducing trifluoropropyltrimethoxysilane with a flow rate of 6 sccm, atomized tetraethoxysilane with a flow rate of 5 sccm, and water vapor with a flow rate of 0.4 sccm. The power is 215 W, and the deposition time is 10.5 min, resulting in a recyclable Cu / Al current collector.

[0062] Comparative Example 1 This comparative example provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. The difference between this method and Example 1 is that the mass of 1,3-bis(aminopropyl)tetramethyldisiloxane in S1 is 20g, which is 10g more than in Example 1. Other process parameters and operating conditions are exactly the same as in Example 1.

[0063] Comparative Example 2 This comparative example provides a method for recycling waste battery materials based on plasma chemical vapor deposition technology. The difference between this method and Example 1 is that the mass of 1,3-bis(aminopropyl)tetramethyldisiloxane in S1 is 1g, which is 9g less than that in Example 1. Other process parameters and operating conditions are exactly the same as those in Example 1.

[0064] Plot the standard curve: Transfer 0.00 ml, 1.00 ml, 2.00 ml, 3.00 ml, 4.00 ml, and 5.00 ml of 200 μg / ml lithium standard solution and plot the standard curve using an atomic absorption spectrophotometer.

[0065] Determination of lithium content in electrode powder: Weigh 0.100 g of untreated electrode powder and place it in a polytetrafluoroethylene (PTFE) crucible. Place the PTFE crucible on a hot plate, add 5 mL of concentrated nitric acid, heat until nearly dry, then stop heating. Add 1 mL of 40 wt.% HF, heat until nearly dry, remove the PTFE crucible, add 10 wt.% nitric acid, and bring to volume to obtain the sample to be tested. Measure the absorbance of the sample and substitute it into the standard curve equation. The lithium content of the electrode powder is 6.4 wt.%.

[0066] Leaching rate determination: The supernatant of the metal salt mixture was taken and diluted to 50 mL. The concentration was determined by atomic absorption spectrometry and converted into a mass fraction in the metal salt mixture. The leaching rate was obtained by comparing it with the lithium content of the electrode powder. The test results are shown in Table 1.

[0067]

[0068] As shown in Table 1, the leaching rates of Comparative Examples 1 and 2 decreased compared to Example 1. Since the amino groups of 1,3-bis(aminopropyl)tetramethyldisiloxane are the main active sites for metal chelation, the excess 1,3-bis(aminopropyl)tetramethyldisiloxane in Comparative Example 1 led to a significant increase in the density of chelation sites in the complex. This dense distribution may cause competitive coordination of metal ions in the solution environment, i.e., multiple chelation groups compete for the same metal ion, thereby reducing the utilization efficiency of individual chelation sites. In Comparative Example 2, the insufficient amount of 1,3-bis(aminopropyl)tetramethyldisiloxane directly resulted in a decrease in the number of amino groups in the complex, a decrease in the density of chelation sites, and a significant weakening of the complex's ability to capture metal ions, thus leading to a decrease in metal recovery rate.

[0069] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for recycling waste battery materials based on plasma chemical vapor deposition technology, characterized in that, The method includes: S1, 1,3-bis(aminopropyl)tetramethyldisiloxane, 3-mercaptopropyltrimethoxysilane, pentafluorophenyltrimethoxysilane, triethylamine and deionized water are dispersed in anhydrous ethanol and reacted to obtain a metal chelating functional network complex. S2, glycidyl methacrylate, NaOH and deionized water are mixed to obtain pre-hydrolyzed glyceryl methacrylate, pre-hydrolyzed glyceryl methacrylate, 1-allyl-3-chloromethylimidazolium, methacryloyloxyethyltrimethylammonium chloride and hexafluorobutyl acrylate are dispersed in an ethanol aqueous solution, azobisisobutyramidine hydrochloride and NaOH are added, and the reaction is carried out to obtain an imidazolium-quaternary ammonium salt fluorinated complex network; S3, place the dried electrode sheet in the first chamber. In the first stage, use argon and hydrogen to clean the surface of the electrode sheet. Transfer the cleaned electrode sheet to the second chamber. In the second stage, introduce helium, heat and atomize trifluoropropyltrimethoxysilane and ultrasonically atomize metal chelate functional network complex solution. After two-step deposition, product A is obtained. S4, product A is transferred to the third chamber. In the third stage, the temperature of the chamber is periodically adjusted to carry out the peeling process, and the peeled active powder, Cu current collector and Al current collector are obtained. In step S5, the Cu current collector and Al current collector are placed in the fourth chamber. In the fourth stage, helium gas is introduced, and a heated and atomized trifluoropropyltrimethoxysilane and an ultrasonically atomized imidazolium-quaternary ammonium salt fluorine-containing complex network solution are used to deposit the impurity trapping layer. In the fifth stage, helium gas is introduced, and a heated and atomized trifluoropropyltrimethoxysilane, atomized tetraethoxysilane and water vapor are used to deposit the inorganic protective layer, resulting in recyclable Cu current collector and Al current collector.

2. The method of claim 1, wherein the method is characterized by, In S1, The mass ratio of 1,3-bis(aminopropyl)tetramethyldisiloxane, 3-mercaptopropyltrimethoxysilane and pentafluorophenyltrimethoxysilane is 10:5:

3.

3. The method of claim 1, wherein the method is characterized by, In S2, The mass ratio of glycidyl methacrylate, 1-allyl-3-chloromethylimidazolium, methacryloyloxyethyltrimethylammonium chloride, hexafluorobutyl acrylate, and azobisisobutyramidine hydrochloride is 2:5:8:3:0.

2.

4. The method of claim 1, wherein the method is characterized by, In S3, the first stage The flow rate of the argon gas is 30-40 sccm; The flow rate of the hydrogen gas is 20-30 sccm; The total radio frequency power of the argon and hydrogen is 150-170W.

5. The method of claim 1, wherein the method is characterized by, In S3, the second stage The flow rate of the helium gas is 150-170 sccm; The flow rate of the heated and atomized trifluoropropyltrimethoxysilane is 5-8 sccm; The flow rate of the ultrasonically atomized metal chelate functional network complex solution is 0.2-0.5 sccm.

6. The method of claim 1, wherein the method is characterized by, In S3, the second stage The two deposition steps are as follows: bottom layer deposition: RF power 100-110W, time 10-15min; top layer deposition: RF power 70-90W, time 20-25min.

7. The method according to claim 1, wherein the method is characterized by, In S4, The periodic temperature adjustment involves adjusting the initial temperature of the chamber to 50°C and periodically raising it to 80°C and then lowering it to 60°C. In the third stage, the stripping process involves setting the instantaneous peak power to 300-320W for 12-15 seconds, then switching to 50-60W and maintaining it for 20-25 seconds, with a total stripping time of 15-18 minutes. 8.The method of recycling waste battery materials based on plasma chemical vapor deposition technology according to claim 1, wherein, In S5, the fourth stage The flow rate of the trifluoropropyltrimethoxysilane is 10-20 sccm; The flow rate of the ultrasonically atomized imidazole-quaternary ammonium salt fluorinated complex network solution is 0.3-0.7 sccm. 9.The method of recycling waste battery materials based on plasma chemical vapor deposition technology according to claim 1, wherein, In S5, the fourth stage The conditions for depositing the impurity trapping layer are: power 100-120W, deposition time 10-15min, and chamber temperature 150℃. 10.The method of recycling waste battery materials based on plasma chemical vapor deposition technology according to claim 1, wherein, In S5, the fifth stage The flow rate of the trifluoropropyltrimethoxysilane is 5-8 sccm; The flow rate of the atomized tetraethoxysilane is 3-6 sccm; The flow rate of the water vapor is 0.2-0.5 sccm; The conditions for depositing the inorganic protective layer are: power 200-220W, deposition time 10-12min, and chamber temperature 180℃.

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