Solvent and method for recycling collection fluid

Abstract

The invention relates to a solvent for dissolving binders and to a method for recovering fluid from batteries, capacitors or waste coatings. The solvent comprises i) cyclopentanone as a first component and ii) carboxylic acid, ascorbic acid, alkyl-substituted urea or lactone as a second component. The present disclosure also relates to a current collector obtained by this method.

Description

Technical Field

[0001] The present invention generally relates to solvents and methods for recovering collected fluids from batteries, capacitors or waste coatings, and more particularly to a solvent for dissolving binders / polymer binders and its use in methods for recovering collected fluids. Background Art

[0002] Various strategies have been adopted in the global efforts to achieve carbon neutrality in order to mitigate climate change. The main strategies include switching from carbon-emitting vehicles to electric vehicles and replacing fossil fuels with renewable energy sources (e.g., solar, wind, hydrothermal, etc.). However, adopting such strategies also brings other challenges, such as the increase in the generation of electronic waste.

[0003] The market for hybrid electric vehicles (HEV) and electric vehicles (EV) is expanding, and the demand for lithium-ion batteries (LIB) is also growing. As the demand for LIB grows, the recycling of waste lithium-ion batteries has also received increasing attention in the past decade. Most recycling processes involve shredding and fine grinding of waste batteries, as well as other harsh processing steps, such as the use of high temperatures and strong acids. However, these methods (e.g., hydrometallurgical methods and pyrometallurgical methods) have obvious disadvantages. For example, when high temperatures and strong acids are used, the current collector is dissolved and mixed with other precious transition metal ions present in the battery. This makes the recovery of high-purity precious transition metal ions complicated because removing the dissolved current collector (e.g., aluminum and copper) is complicated and expensive. In addition, hydrometallurgical methods such as leaching with strong acids are environmentally unfriendly, difficult to handle, and may be harmful to health. Pyrometallurgical methods involve the use of high temperatures, which have the disadvantage of requiring high energy input and may produce toxic gases, which need to be further treated before releasing these toxic gases into the atmosphere.

[0004] Therefore, it is necessary to provide a solvent and method for recovering fluid from batteries, capacitors or waste paint to overcome or at least improve one or more of the above disadvantages. Summary of the invention

[0005] In one aspect of the present disclosure, there is provided a solvent for dissolving an adhesive, the solvent comprising:

[0006] (i) cyclopentanone as a first component; and

[0007] (ii) Carboxylic acid, ascorbic acid, alkyl-substituted urea or lactone as the second component.

[0008] Advantageously, the solvent may be non-corrosive, which advantageously allows delamination / dislodgement of the electrode material from the current collector without causing any corrosion to the current collector.

[0009] Also advantageously, the solvent can be cost-effective, non-toxic and environmentally friendly, thereby providing a safe, sustainable and scalable solution for large-scale direct recycling of batteries or capacitors.

[0010] The solvent can also advantageously be reused multiple times, thereby saving further costs.

[0011] In another aspect of the present disclosure, a method for recovering a current from a battery, capacitor or waste coating comprising an electrode material, a current collector and a binder / polymer binder is provided, the method comprising adding a disassembled battery or capacitor or waste coating to a solvent disclosed herein.

[0012] Advantageously, the method may not require grinding the current collector into a fine powder together with the electrode material, which reduces the risk of releasing harmful pollutants, dust or fumes into the environment. Without the need for grinding, the disclosed method may also make it easier to separate and extract the current collector from a waste battery or capacitor.

[0013] Unlike hydrometallurgical or pyrometallurgical methods, the methods of the present invention can advantageously be carried out under ambient conditions, which avoids harsh conditions, such as highly acidic environments that may lead to leaching of metal components. In addition, the methods of the present disclosure avoid the use of high temperatures, such as those required to melt batteries or capacitors (smelting), which require high levels of energy input.

[0014] Unlike pyrometallurgical methods, the process of the present invention may also advantageously not release or emit toxic gases or fumes that could pose health and environmental risks, thereby eliminating the need for additional pre-treatment processes prior to release into the environment.

[0015] Also advantageously, the methods of the present invention may involve a simple one-step separation of the current collector from spent batteries or capacitors or spent coatings, thereby eliminating the need for further extraction or extensive post-processing (e.g., leaching or re-calcination with metal precursors).

[0016] In another aspect of the present disclosure, provided is a current collector obtained by the method disclosed herein.

[0017] Advantageously, the current collector obtained by the method of the present disclosure can be used directly as an electrode material, or reused as a current collector for battery applications.

[0018] Also advantageously, the ability to directly use recycled current collectors reduces the energy consumption and overall cost of producing new batteries. Recycling and reusing current collectors can also reduce the costs associated with procuring and processing new raw materials, thereby reducing costs and improving affordability to consumers.

[0019] Equally advantageously, direct recycling and reuse of batteries can prevent environmental contamination by hazardous substances such as heavy metals and toxic chemicals, as the risk of these substances entering ecosystems, groundwater or air when improperly disposed of can be reduced. In addition, direct recycling and reuse of recycled current collectors can help reintroduce materials from used batteries into the production cycle, thus forming a closed-loop system. This promotes a circular economy approach, reduces waste, and ensures a sustainable material supply for future battery production.

[0020] definition

[0021] Unless otherwise defined herein, scientific and technical terms used in this application shall have the meanings commonly understood by those of ordinary skill in the art. Generally, the terms and techniques used in connection with the chemistry described herein are all well known and commonly used in the art.

[0022] As used herein, the term "current collector" refers to a substrate of an electrode material capable of conducting electrons. For example, the current collector may include a metal, a metal-containing, or a conductive current collector.

[0023] The term "electrode material" as used herein refers to a material including an anode material, a cathode material, or a mixture thereof.

[0024] The term "binder" as used herein refers to a component of a battery electrode assembly that functions as a binding agent to fix and secure active material particles, conductive additives, and other electrode ingredients into a cohesive, mechanically stable, and conductive matrix structure.

[0025] As used herein, "slurry" or "paste coating" refers to a mixture or coating that partially or completely covers the current collector in the battery and acts as an electrode (cathode / anode) in the battery. Slurry or paste coating generally includes a thick suspension of active materials, conductive additives, binders and solvents.

[0026] As used herein, "waste coating" or "waste slurry coating" refers to slurry that is applied to a current collector during a coating process and subsequently rejected due to quality control measures, such as rejection due to uneven coating, under-coating, or over-coating, etc. "Waste coating" may also refer to a current collector that contains slurry that is rejected for the above reasons.

[0027] Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as the singular integer, step or element expressly encompass both the singular and the plural of the recited integer, step or element.

[0028] Unless otherwise stated, the term "comprise" and its grammatical variations are intended to represent an "open" or "inclusive" language such that they include the listed elements but also allow for additional, non-listed elements.

[0029] As used herein, the term "about" in the context of formulation component concentrations typically refers to ±5% of the stated value, more typically ±4% of the stated value, more typically ±3% of the stated value, more typically ±2% of the stated value, more typically ±1% of the stated value, and even more typically ±0.5% of the stated value.

[0030] In the present disclosure, certain embodiments may be disclosed in a range format. It should be understood that the description of the range format is only for the purpose of convenience and brevity, and should not be interpreted as constituting a hard limit to the disclosed range. Therefore, the description of the range should be deemed to specifically disclose all possible sub-ranges and each numerical value within the range. For example, the description of the range of 1 to 6 should be deemed to have specifically disclosed sub-ranges, such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, 3 to 6, and each number within the range, such as 1, 2, 3, 4, 5 and 6. This applies regardless of the breadth of the range.

[0031] Certain embodiments may also be described herein in a broad and general manner. Each narrower class and subgeneric grouping within the general disclosure also forms part of this disclosure. This includes the general description of the embodiments with a proviso or negative limitation removing any subject matter from the class, regardless of whether the removed material is specifically recited herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1

[0033] Figure 1 Schematic diagram of a method for recycling batteries, capacitors and waste paint to obtain current collectors in an embodiment of the present invention. The recycled current collectors can be reused in new batteries and other applications.

[0034] Figure 2

[0035] Figure 2 This is the Raman spectrum of cyclopentanone (CP).

[0036] Figure 3

[0037] Figure 3 A series of Raman spectra of (a) 3 g CP in 0.9 g water; (b) 3 g CP and 0.3 g L-ascorbic acid in 0.6 g water; (c) pure CP; and (d) deionized water, with the 400 cm-1 wavelength shown on the right. -1Up to 1900cm -1 Zoomed in spectrum of . The peaks in the shaded area represent peak shifts due to the mixture of cyclopentanone and water.

[0038] Figure 4

[0039] Figure 4 A series of Raman spectra of (a) 3 g CP and 0.3 g 1,2,4,5-pyromellitic acid in 0.15 g water; and (b) pure CP, with the peaks in the shaded area indicating the presence of 1,2,4,5-pyromellitic acid.

[0040] Figure 5

[0041] Figure 5 are photographs showing the pH values ​​of various solvents of the present invention: (I) 3 g CP in 0.9 g water; (II) 0.3 g L-ascorbic acid in 3.6 g water; (III) 3 g CP and 0.3 g L-ascorbic acid in 0.6 g water; and (IV) 3 g CP and 0.3 g 1,2,4,5-benzenetetracarboxylic acid in 0.15 g water.

[0042] Figure 6

[0043] Figure 6 is a scanning electron microscope (SEM) image of the recycled aluminum (Al) current collector in an embodiment of the present invention.

[0044] Figure 7

[0045] Figure 7 yes Figure 6 A series of SEM images of the recycled aluminum current collector.

[0046] Figure 8

[0047] Figure 8 yes Figure 6 Energy dispersive X-ray spectroscopy (EDS) spectra of the elemental composition of the recycled Al current collector.

[0048] Fig. 9

[0049] Fig. 9 yes Figure 6 X-ray diffraction (XRD) pattern of the recycled Al current collector.

[0050] Fig.10

[0051] Fig.10 is a schematic diagram of an electrochemical cell configuration using the recycled current collector of the present invention as the anode and a Prussian blue analog (PBA) as the cathode.

[0052] Fig.11

[0053] Fig.11 It is shown Fig.10 The electrochemical cell is between 1.6V and 0.6V at 25mA·g -1 Graph of the constant current charge and discharge curves for 100 cycles at a current density of 1.38kV.

[0054] Fig.12

[0055] Fig.12 It is shown Fig.10 The electrochemical cell is between 1.6V and 0.6V at 25mA·g -1 Graphs of constant current charge and discharge curves after (i) 1 cycle; (ii) 2 cycles; and (iii) 5 cycles at current density.

[0056] Fig.13

[0057] Fig.13 The comparison is between two lithium nickel cobalt manganese oxide 622 (NMC622) / lithium half-cells at 160 mA g -1 A series of graphs of galvanostatic charge and discharge curves for 100 cycles of current density, where NMC 622 is coated with (a) new aluminum current collector and (b) recycled aluminum current collector of the present invention, respectively.

[0058] Fig.14

[0059] Fig.14 ] are Raman spectra of a sample aluminum foil (virgin aluminum) and an aluminum foil recovered using the method of the present invention (recycled aluminum).

[0060] Fig.15

[0061] Fig.15 is a series of photographs showing aluminum foil recycled using the various conditions in Table 2.

[0062] Fig.16

[0063] Fig.16 It is a series of photographs of the current collectors recovered after 2 minutes using the solvents in Table 3 (upper side: solvent 1; lower left: LA-4; lower right: LA-3).

[0064] Fig.17

[0065] Fig.17 These are photographs of the current collectors recovered after using the solvents listed in Table 3 for 5 minutes (left: LA-4; right: LA-3).

[0066] Fig.18

[0067] Fig.18 It is a series of photographs of the current collectors recovered after 20 minutes using the solvents in Table 3 (top: solvent 1; bottom left: LA-4; bottom right: LA-3).

[0068] Fig.19

[0069] Fig.19 is a series of photographs of current collectors recovered after using the solvents in Table 3 for 1.5 hours (upper left / upper right: solvent 1; lower left: LA-4; lower right: LA-3).

[0070] Fig. 20

[0071] Fig. 20 is a series of photographs of the current collectors recovered after using the following solvents for 1 hour (upper side: solvent 7; lower left: pure CP; lower right: pure γ-butyrolactone).

[0072] Fig.21a

[0073] Fig.21a This is a photo of the waste batteries in Example 6 after mechanical treatment.

[0074] Figure 21b

[0075] Figure 21b is from Fig.21a Photo of the coated current collector separated from the spent battery.

[0076] Fig. 22

[0077] Fig. 22 is a series of photographs showing current collectors recovered from waste batteries using solvent 1 (upper left: t=0 min; upper right: t=2 min; lower side: 3 hours).

[0078] Fig.23

[0079] Fig.23 is a series of photographs showing successful removal of the slurry coating from the current collector.

[0080] Fig.24

[0081] Fig.24 is a series of photographs showing the recovery of electrode materials.

[0082] Detailed description with drawings

[0083] refer to Figure 1 (a) and Figure 1(b) shows an overview of the recovery of fluid from waste batteries using the solvents and methods disclosed herein. The waste batteries are first shredded and cleaned to expose internal components, such as electrode materials and coated current collectors. The shredded batteries are then further cut into smaller pieces and immersed in the solvent of the present invention to dissolve the binder / polymer binder, thereby facilitating the stripping / detachment of the electrode material / paste coating from the current collector. The detached current collector is then filtered, cleaned, and can be used directly for other applications.

[0084] refer to Figure 1 (c), directly immersing the waste coating in the solvent of the present invention to dissolve the binder / polymer binder, thereby facilitating the stripping / detachment of the electrode material from the coated current collector. The recovered current collector can then be directly used in other applications, such as for battery manufacturing and testing. DETAILED DESCRIPTION

[0085] The detailed description below is exemplary only and is not intended to limit the invention or the application and the use of the invention. In addition, no theory should be bound by the above background technology of the invention or the following specific embodiments. The purpose of the present invention is to provide a solvent for dissolving adhesives and a method for recovering collected fluids from batteries, capacitors or waste coatings, which overcomes or at least improves one or more of the disadvantages previously described in the background technology of the present disclosure.

[0086] Existing methods for recovering fluid from batteries, capacitors or waste paint include laborious chopping, crushing and grinding of waste batteries, and other high energy consumption and harsh processing steps, such as using high temperature and strong acid. These methods have many disadvantages. First, strong acid is not environmentally friendly, may be harmful to health, and difficult to handle. Secondly, even if strong acid is used, high energy consumption steps using high temperature are required. Thirdly, toxic gases and other products may be released, which require further treatment before being released into the environment. In addition, these methods involve dissolving and mixing the current collector with other precious transition metal ions. This further complicates the recovery of high purity current collectors and precious transition metal ions, and removing the dissolved current collector is both complicated and expensive.

[0087] To overcome the challenges discussed, the present invention is directed to a solvent for recycling fluids from batteries, capacitors or waste paint that is environmentally friendly, easy to prepare, simple to use, and cost-effective.

[0088] Batteries typically contain electrode materials, current collectors, and a binder / polymer binder.

[0089] The present invention includes a solvent for dissolving a binder / polymer binder, the solvent comprising:

[0090] (i) cyclopentanone as a first component; and

[0091] (ii) Carboxylic acid, ascorbic acid, alkyl-substituted urea or lactone as the second component.

[0092] The weight ratio of the first component to the second component can be about 1:1 to about 60:1, about 1:1 to about 59:1, about 1:1 to about 58:1, about 1:1 to about 57:1, about 1:1 to about 56:1, about 1:1 to about 55:1, about 1:1 to about 54:1, about 1:1 to about 53:1, about 1:1 to about 52:1, about 1:1 to about 51:1, about 1:1 to about 50:1, about 1:1 to about 49:1, about 1:1 to about 48:1, about 1:1 to about 47:1, about 1:1 to about 46:1, about 1:1 to about 45:1, about 1:1 to about 44:1 1, about 1:1 to about 43:1, about 1:1 to about 42:1, about 1:1 to about 41:1, about 1:1 to about 40:1, about 1:1 to about 39:1, about 1:1 to about 38:1, about 1:1 to about 37:1, about 1:1 to about 36:1, about 1:1 to about 35:1, about 1:1 to about 34:1, about 1:1 to about 33:1, about 1:1 to about 32:1, about 1:1 to about 31:1, about 1:1 to about 30:1, about 1:1 to about 29:1, about 1:1 to about 28:1, about 1:1 to about 27:1, about 1:1 to about 26:1, about 1 :1 to about 25:1, about 1:1 to about 24:1, about 1:1 to about 23:1, about 1:1 to about 22:1, about 1:1 to about 21:1, about 1:1 to about 20:1, about 1:1 to about 19:1, about 1:1 to about 18:1, about 1:1 to about 17:1, about 1:1 to about 16:1, about 1:1 to about 15:1, about 1:1 to about 14:1, about 1:1 to about 13:1, about 1:1 to about 12:1, about 1:1 to about 11:1, about 1:1 to about 10:1, about 1:1 to about 9:1, about 1:1 to about 8:1, about 1:1 to about 7:1 1, about 1:1 to about 6:1, about 1:1 to about 5:1, about 1:1 to about 4.5:1, about 1:1 to about 4:1, about 1:1 to about 3.5:1, about 1:1 to about 3:1, about 1:1 to about 2.5:1, about 1:1 to about 2:1, about 1:1 to about 1.5:1, about 1:1 to about 1.25:1, about 1.25:1 to about 60:1, about 1.5:1 to about 60:1, about 2:1 to about 60:1, about 2.5:1 to about 60:1, about 3:1 to about 60:1, about 3.5:1 to about 60:1, about 4:1 to about 60:1, about 4.1 to about 60:1, about 5:1 to about 60:1, about 5:1 to about 60:1, about 6:1 to about 60:1, about 7:1 to about 60:1, about 8:1 to about 60:1, about 9:1 to about 60:1, about 10:1 to about 60:1, about 11:1 to about 60:1, about 12:1 to about 60:1, about 13:1 to about 60:1, about 14:1 to about 60:1, about 15:1 to about 60:1, about 16:1 to about 60:1, about 17:1 to about 60:1, about 18:1 to about 60:1, about 19:1 to about 60:1, about 20:1 to about 60:1 1, about 21:1 to about 60:1, about 22:1 to about 60:1, about 23:1 to about 60:1, about 24:1 to about 60:1, about 25:1 to about 60:1, about 26:1 to about 60:1, about 27:1 to about 60:1, about 28:1 to about 60:1, about 29:1 to about 60:1, about 30:1 to about 60:1, about 31:1 to about 60:1, about 32:1 to about 60:1, about 33:1 to about 60:1, about 34:1 to about 60:1, about 35:1 to about 60:1, about 36:1 to about 60:1, about 1 to about 60:1, about 47:1 to about 60:1, about 48:1 to about 60:1, about 49:1 to about 60:1, about 50:1 to about 60:1, about 51:1 to about 60:1, about 52:1 to about 60:1, about 53:1 to about 60:1, about 54:1 to about 60:1, about 55:1 to about 60:1, about 56:1 to about 60:1, about 57:1 to about 60:1, about 58:1 to about 60:1, about 59:1 to about 60:1, about 60:1 1 to about 60:1, about 54:1 to about 60:1, about 55:1 to about 60:1, about 56:1 to about 60:1, about 57:1 to about 60:1, about 58:1 to about 60:1, about 59:1 to about 60:1, about 1:1, about 1.1:1, about 1.2:1, about 1.3:1, about 1.4:1, about 1.5:1, about 1.6:1, about 1.7:1, about 1.8:1, about 1.9:1, about 2:1, about 2.25:1, about 2.5:1, about 2.75:1, about 3:1, about 3.5:1, about 4:1, about 4.5:1, about 5:1, about 6:1, about 7:1, about 8:1, about 9:1, about 10:1, about 11:1, about 12:1, about 13:1, about 14:1, about 15:1, about 16:1, about 17:1, about 18:1, about 19:1, about 20:1, about 21:1, about 22:1, about 23:1, about 24:1, about 25:1, about 26:1, about 27:1, about 28:1, about 29:1, about 30:1, about 31:1, about 32:1, about 33:1, about 34:1, about 35:1, about 36:1, about 37:1, about 38:1, about 39:1, about 40:1, about 41:1, about 42:1, about 43:1, about 44:1, about 45:1, about 46:1, about 47:1, about 48:1, about 49:1, about 50:1, about 51:1, about 52:1, about 5x:1, about 54:1, about 55:1, about 56:1, about 57:1, about 58:1, about 59:1, about 60:1, or any range or value therebetween. .

[0093] In some embodiments, the weight ratio of the first component to the second component can be about 10:1 to about 30:1, about 10:1 to about 29:1, about 10:1 to about 28:1, about 10:1 to about 27:1, about 10:1 to about 26:1, about 10:1 to about 25:1, about 10:1 to about 24:1, about 10:1 to about 23:1, about 10:1 to about 22:1, about 10:1 to about 21:1, about 10:1 to about 20:1, about 10:1 to about 19:1, about 10:1 to about 18:1, about 10:1 to about 17:1, about 10:1 to about 16:1, about 10:1 to about 15:1. :1, about 10:1 to about 14:1, about 10:1 to about 13:1, about 10:1 to about 12:1, about 10:1 to about 11.75:1, about 10:1 to about 11.5:1, about 10:1 to about 11.25:1, about 10:1 to about 11:1, about 10:1 to about 10.75:1, about 10:1 to about 10.5:1, about 10:1 to about 10.25:1, about 10:1 to about 30:1, about 10.25:1 to about 30:1, about 10.5:1 to about 30:1, about 10.75:1 to about 30:1, about 11:1 to about 30:1, about 11.25:1 1 to about 30:1, about 11.75:1 to about 30:1, about 12:1 to about 30:1, about 13:1 to about 30:1, about 14:1 to about 30:1, about 15:1 to about 30:1, about 16:1 to about 30:1, about 17:1 to about 30:1, about 18:1 to about 30:1, about 19:1 to about 30:1, about 20:1 to about 30:1, about 21:1 to about 30:1, about 22:1 to about 30:1, about 23:1 to about 30:1, about 24:1 to about 30:1, about 25:1 to about 30:1, about 26:1 to about 30:1, about 27:1 to about 30:1, about 28:1 to about 30:1, about 29:1 to about 30:1, about 10:1, about 10.25:1, about 10.5:1, about 10.75:1, about 11:1, about 11.25:1, about 11.5:1, about 11.75:1, about 12:1, about 13:1, about 14:1, about 15:1, about 16:1, about 17:1, about 18:1, about 19:1, about 20:1, about 21:1, about 22:1, about 23:1, about 24:1, about 25:1, about 26:1, about 27:1, about 28:1, about 29:1, about 30:1, or any range or value therebetween.

[0094] The second component of the solvent may include a carboxylic acid. The carboxylic acid as the second component in the solvent may act as a reducing agent to allow the cathode to be better reduced and may promote the dissolution of the binder / polymer binder. The carboxylic acid may also act like a leaching agent to dissolve the transition metal ions. The carboxylic acid may also act as a chelating agent to form a stable chelate with the heavy metal, thereby increasing the efficiency of removing the electrode material from the current collector. In addition, the carboxylic acid may form hydrogen bonds to increase the efficiency of removing the electrode material from the current collector.

[0095] The carboxylic acid can be C 2 -C 12 Dicarboxylic acid, C 3 -C 12 tricarboxylic acid or C 4 -C 12 Tetracarboxylic acid. The carboxylic acid may be selected from C 2 Dicarboxylic acid, C 3 Dicarboxylic acid, C 4 Dicarboxylic acid, C 5 Dicarboxylic acid, C 6 Dicarboxylic acid, C 7 Dicarboxylic acid, C 8 Dicarboxylic acid, C 9 Dicarboxylic acid, C 10 Dicarboxylic acid, C 11 Dicarboxylic acid, C 12 Dicarboxylic acid, C 3 Tricarboxylic acid, C 4 Tricarboxylic acid, C 5 Tricarboxylic acid, C 6 Tricarboxylic acid, C 7 Tricarboxylic acid, C 8 Tricarboxylic acid, C 9 Tricarboxylic acid, C 10 Tricarboxylic acid, C 11 Tricarboxylic acid, C 12 Tricarboxylic acid, C 4 Tetracarboxylic acid, C 4 Tetracarboxylic acid, C 5 Tetracarboxylic acid, C 6 Tetracarboxylic acid, C 7 Tetracarboxylic acid, C 8 Tetracarboxylic acid, C 9 Tetracarboxylic acid, C 10 Tetracarboxylic acid, C 11 Tetracarboxylic acid or C 12 A group consisting of tetracarboxylic acids.

[0096] The dicarboxylic acid may be oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, 1,4-cyclohexanedicarboxylic acid or sebacic acid. The dicarboxylic acid may also be azelaic acid, undecanedioic acid and / or dodecanedioic acid.

[0097] The tricarboxylic acid may be ethane-1,1,1-tricarboxylic acid, 1,1,2-hydrazinetricarboxylic acid, prop-1-ene-1,2,3-tricarboxylic acid, 2-oxoethane-1,1,2-tricarboxylic acid, ethylene oxide-2,2,3-tricarboxylic acid, 2-hydroxypropane-1,2,3-tricarboxylic acid (citric acid), prop-1-ene-1,2,3-tricarboxylic acid (aconitic acid), or propane-1,2,3-tricarboxylic acid. The tricarboxylic acids may also include ethylene-1,1,2-tricarboxylic acid, ethane-1,1,2-tricarboxylic acid, prop-2-yne-1,1,3-tricarboxylic acid, cycloprop-2-ene-1,1,2-tricarboxylic acid, cyclopropane-1,1,2-tricarboxylic acid, aziridine-2,2,3-tricarboxylic acid, 1-methylethane-1,1,2-tricarboxylic acid, 1-hydroxypropane-1,2,3-tricarboxylic acid (isocitric acid), benzene-1,3,5-tricarboxylic acid (trimellitic acid) and / or propane-1,2,3-tricarboxylic acid.

[0098] The tetracarboxylic acid may be selected from the group consisting of 1,2,4,5-benzenetetracarboxylic acid and ethylenetetracarboxylic acid. The tetracarboxylic acid may also include ethane-1,1,2,2-tetracarboxylic acid, ethane-1,1,1,2-tetracarboxylic acid, cyclopropane-1,1,2,2-tetracarboxylic acid, prop-1-ene-1,1,2,3-tetracarboxylic acid, prop-1-ene-1,1,3,3-tetracarboxylic acid, prop-2-ene-1,1,2,3-tetracarboxylic acid, prop-2-ene-1,1,1,2-tetracarboxylic acid, cyclopropane-1,1,2,3-tetracarboxylic acid, ethylene oxide-2,2,3, 3-tetracarboxylic acid, propane-1,1,3,3-tetracarboxylic acid, propane-1,1,2,3-tetracarboxylic acid, propane-1,1,1,3-tetracarboxylic acid, propane-1,1,1,2-tetracarboxylic acid, propane-1,2,2,3-tetracarboxylic acid, propane-1,1,2,2-tetracarboxylic acid, 1-aminoethane-1,1,2,2-tetracarboxylic acid, 1-hydroxyethane-1,1,2,2-tetracarboxylic acid and 2-hydroxyethane-1,1,1,2-tetracarboxylic acid.

[0099] The second component of the solvent may include alkyl substituted urea. The alkyl substituted urea may be selected from the group consisting of methyl urea, dimethyl urea, trimethyl urea, tetramethyl urea, diethyl urea, tetraethyl urea and propyl urea. The alkyl substituted urea may also include ethyl urea, triethyl urea, dipropyl urea, tripropyl urea and / or tetrapropyl urea.

[0100] The second component of the solvent may include a lactone. Lactone itself can be a green, low-cost and effective solvent for dissolving the adhesive / polymer binder. However, in general, high processing temperatures of about 100° C. are required for lactones to dissolve the adhesive / polymer binder. However, the inventors have advantageously found that the combination of cyclopentanone and lactone avoids the need to use high processing temperatures.

[0101] The lactone may be selected from the group consisting of γ-butyrolactone, ε-caprolactone and D-glucono-δ-lactone. The lactone may also be β-propiolactone.

[0102] The solvent may also include water. By using water in the solvent, the solvent can better dissolve the components of the solvent, wherein in some cases, water improves the solubility of the first component or the second component in the solvent. For example, ascorbic acid may not be well dissolved in cyclopentanone. However, using water can make ascorbic acid better dissolved in the solvent.

[0103] By using limited and controlled amounts of water and an adjusted pH, a "water inorganic" environment can be created. In this way, metal ions from batteries and waste paint will not leach out. pH can also be a factor that affects the leachability of heavy or transition metals.

[0104] The weight ratio of the second component to water can be about 10:1 to about 1:5, about 9:1 to about 1:5, about 8:1 to about 1:5, about 7:1 to about 1:5, about 6:1 to about 1:5, about 5:1 to about 1:5, about 4:1 to about 1:5, about 3:1 to about 1:5, about 2:1 to about 1:5, about 1.75:1 to about 1:5, about 1.5:1 to about 1:5, about 1.25:1 to about 1:5, about 1:1 to about 1:5, about 1:1.25 to about 1:5, about 1:1.5 to about 1:5, about 1:1.75 to about 1:5, about 1:2 to about 1:5, about 1:2.25 to about 1:5, about 1:2.5 to about 1:5, about 1:2.75 to about 1:5, about 1:3 to about 1:5, about 1:3.25 to about 1:5, about 1:3.5 to about 1:5, about 1:3.75 to about 1:5, about 1:4 to about 1:5, about 1:4.25 to about 1:5, about 1:4.5 to about 1:5, about 1:4.75 to about 1:5, about 10:1 to about 1:4.75, about 10:1 to about 1:4.5, about 10:1 to about 1:4.25, about 10:1 to about 1:5 :4, about 10:1 to about 1:3.75, about 10:1 to about 1:3.5, about 10:1 to about 1:3.25, about 10:1 to about 1:3, about 10:1 to about 1:2.75, about 10:1 to about 1:2.5, about 10:1 to about 1:2.25, about 10:1 to about 1:2, about 10:1 to about 1:1.75, about 10:1 to about 1:1.5, about 10:1 to about 1:1.25, about 10:1 to about 1:1, about 10:1 to about 1.25:1, about 10:1 to about 1.5:1, about 10:1 From about 10:1 to about 1.75:1, from about 10:1 to about 2:1, from about 10:1 to about 2.25:1, from about 10:1 to about 2.5:1, from about 10:1 to about 2.75:1, from about 10:1 to about 3:1, from about 10:1 to about 3.25:1, from about 10:1 to about 3.5:1, from about 10:1 to about 3.75:1, from about 10:1 to about 4:1, from about 10:1 to about 5:1, from about 10:1 to about 6:1, from about 10:1 to about 7:1, from about 10:1 to about 8:1, from about 10:1 to about 9:1, or any range or value therebetween.

[0105] The pH of the solution can be from about 3 to about 7, from about 3 to about 6.5, from about 3 to about 6, from about 3 to about 5.5, from about 3 to about 5, from about 3 to about 4.5, from about 3 to about 4, from about 3 to about 3.5, from about 3.5 to about 7, from about 3.5 to about 6.5, from about 3.5 to about 6, from about 3.5 to about 5.5, from about 3.5 to about 5, from about 3.5 to about 4.5, from about 3.5 to about 4.5, from about 4 to about 7, from about 4 to about 6.5, from about 4 to about 6, from about 4 to about 5.5, from about 4 to about 5, from about 4 to about 4.5, from about 4.5 to about 7, from about 4.5 to about 6. From about 4.5 to about 5.5, from about 4.5 to about 5, from about 5 to about 7, from about 5 to about 6.5, from about 5 to about 6, from about 5 to about 5.5, from about 5.5 to about 7, from about 5.5 to about 6.5, from about 5.5 to about 6, from about 6 to about 7, from about 6 to about 6.5, from about 6.5 to about 7, or at most about 3, at most about 3.5, at most about 4, or at most about 4.5, or at most about 5, or at most about 5.5, at most about 6, at most about 6.5, at most about 7; or about 4, about 4.5, about 5, about 5.5, about 6, about 6.5, about 7, or any range or value therebetween.

[0106] Solvents may include:

[0107] (i) cyclopentanone as a first component; and

[0108] (ii) L-succinic acid, 1,2,4,5-pyromellitic acid, malonic acid, sebacic acid, L-ascorbic acid, tetramethylurea or γ-butyrolactone as the second component.

[0109] Solvents may include:

[0110] (i) cyclopentanone as a first component; and

[0111] (ii) L-succinic acid, 1,2,4,5-pyromellitic acid, malonic acid, sebacic acid, L-ascorbic acid or tetramethylurea as a second component,

[0112] wherein the weight ratio of the first component to L-succinic acid, 1,2,4,5-pyromellitic acid, malonic acid, sebacic acid, L-ascorbic acid or tetramethylurea is from about 30:1 to about 10:1, or

[0113] The weight ratio of the first component to γ-butyrolactone is about 1:1.

[0114] By utilizing the above solvents, strong acids and harsh conditions, such as high temperatures, are not required. The solvents can be used to dissolve the binder / polymer binder and result in the recovery of the current collector.

[0115] The present invention also includes a method for recovering a current collector from a battery, capacitor or waste coating comprising an electrode material, a current collector and a binder / polymer binder, the method comprising adding the disassembled battery or capacitor or the waste coating to a solvent disclosed in the present invention. The solvent dissolves the binder / polymer binder and allows the current collector to be physically separated from the battery, capacitor or waste coating.

[0116] During the dissolution of the binder / polymer binder, the solvent can also release or separate the slurry, slurry coating or waste coating. The slurry or slurry coating can be a mixture or coating that partially or completely covers the current collector in the battery. The slurry or slurry coating can generally include a thick suspension of active materials, conductive additives, binders and solvents. The slurry or slurry coating can serve as an electrode (cathode / anode) in the battery. The solvent can dissolve the binder / polymer binder, release or separate the slurry, slurry coating or waste coating, and cause the slurry, slurry coating or waste coating to separate or peel off from the current collector. This results in removing the slurry, slurry coating or waste coating to obtain the current collector.

[0117] Therefore, the present invention also includes a method for recovering electrode materials from batteries, capacitors or waste coatings. The present invention also includes a method for recovering binders / polymer binders from batteries, capacitors or waste coatings.

[0118] Disassembled batteries or capacitors may include batteries or capacitors that have been crushed, shredded, split, broken, or punctured, either manually (by hand) or by machine.

[0119] The method can be a simple, easy to implement, green and environmentally friendly process, and is a low-cost and cost-effective method for recovering collected fluids, electrode materials or adhesives / polymer binders from batteries, capacitors or waste coatings. The solvent used in the method can be reused to recover collected fluids, electrode materials or adhesives / polymer binders from batteries, capacitors or waste coatings. The method is safe and scalable for large-scale applications.

[0120] The method can be performed at a temperature of at least about 30°C, at least about 35°C, at least about 40°C, at least about 45°C, at least about 50°C, at least about 55°C, at least about 60°C, at least about 65°C, at least about 70°C, at least about 75°C, at least about 80°C, at least about 85°C, at least about 90°C, at least about 95°C, about 40°C to about 100°C, about 41°C to about 100°C, about 42°C to about 100°C, about 43°C to about 100°C, about 44°C to about 100°C, about 45°C to about 100°C, about 46°C to about 100°C, about 47°C to about 100°C, about 48°C to about 100°C, about 49°C to about 100°C, about 50°C to about 100°C, about 51°C to about 100°C, about 52°C to about 100°C, about ℃ to about 100 ℃, about 53 ℃ to about 100 ℃, about 54 ℃ to about 100 ℃, about 55 ℃ to about 100 ℃, about 56 ℃ to about 100 ℃, about 57 ℃ to about 100 ℃, about 58 ℃ to about 100 ℃, about 59 ℃ to about 100 ℃, about 60 ℃ to about 100 ℃, about 61 ℃ to about 100 ℃, about 62 ℃ to about 100 ℃, about 63 ℃ to about 100 ℃, about 64 ℃ to about 100 ℃, about 65 ℃ to about 100 ℃, about 66 ℃ to about 100 ℃, about 67 ℃ to about 100 ℃, about 68 ℃ to about 100 ℃, about 69 ℃ to about 100 ℃, about 70 ℃ to about 100 ℃, about 71 ℃ to about 100 ℃, about 72 ℃ to about 100 ℃, about 73 ℃ to about 100 ℃, about 74 ℃ to about 100 ℃, about 75 ℃ to about 10 ℃, about 76 ℃ to about 100 ℃, about 77 ℃ to about 100 ℃, about 78 ℃ to about 100 ℃, about 79 ℃ to about 100 ℃, about 80 ℃ to about 100 ℃, about 81 ℃ to about 100 ℃, about 82 ℃ to about 100 ℃, about 83 ℃ to about 100 ℃, about 84 ℃ to about 100 ℃, about 85 ℃ to about 100 ℃, about 86 ℃ to about 100 ℃, about 87 ℃ to about 100 ℃, about 88 ℃ to about 100 ℃, about 89 ℃ to about 100 ℃, about 90 ℃ to about 100 ℃, about 91 ℃ to about 100 ℃, about 92 ℃ to about 100 ℃, about 93 ℃ to about 100 ℃, about 94 ℃ to about 100 ℃, about 95 ℃ to about 100 ℃, about 96 ℃ to about 100 ℃, about 97 ℃ to about 100 ℃, about 98 ℃ to about 100 ℃ ℃ to about 100 ℃, about 99 ℃ to about 100 ℃, about 40 ℃ to about 99 ℃, about 40 ℃ to about 98 ℃, about 40 ℃ to about 97 ℃, about 40 ℃ to about 96 ℃, about 40 ℃ to about 95 ℃, about 40 ℃ to about 94 ℃, about 40 ℃ to about 93 ℃, about 40 ℃ to about 92 ℃, about 40 ℃ to about 91 ℃, about 40 ℃ to about 90 ℃, about 40 ℃ to about 89 ℃, about 40 ℃ to about 88 ℃, about 40 ℃ to about 87 ℃, about 40 ℃ to about 86 ℃, about 40 ℃ to about 85 ℃, about 40 ℃ to about 84 ℃, about 40 ℃ to about 83 ℃, about 40 ℃ to about 82 ℃, about 40 ℃ to about 81 ℃, about 40 ℃ to about 80 ℃, about 40 ℃ to about 79 ℃, about 40 ℃ to about 78 ℃, about 40 ℃ to about 77 ℃,From about 40°C to about 76°C, from about 40°C to about 75°C, from about 40°C to about 74°C, from about 40°C to about 73°C, from about 40°C to about 72°C, from about 40°C to about 71°C, from about 40°C to about 70°C, from about 40°C to about 69°C, from about 40°C to about 68°C, from about 40°C to about 67°C, from about 40°C to about 66°C, from about 40°C to about 65°C, from about 40°C to about 64°C, from about 40°C to about 63°C, from about 40°C to about 62°C, from about 40°C to about 61°C, from about 40°C to about 60°C, from about 40°C to about 59°C, from about 40°C to about 58°C, from about 40°C to about 57°C, from about 40°C to about 56°C, from about 40°C to about 55°C, from about 40°C to about 54°C, from about 40°C to about 53°C, from about 40°C to about 52°C, From about 40°C to about 51°C, from about 40°C to about 50°C, from about 40°C to about 49°C, from about 40°C to about 48°C, from about 40°C to about 47°C, from about 40°C to about 46°C, from about 40°C to about 45°C, from about 40°C to about 44°C, from about 40°C to about 43°C, from about 40°C to about 42°C, from about 40°C to about 41°C, from about 60°C to about 99°C, from about 60°C to about 98°C, from about 60°C to about 97°C, from about 60°C to about 96°C, from about 60°C to about 95°C, from about 60°C to about 94°C, from about 60°C to about 93°C, from about 60°C to about 92°C, from about 60°C to about 91°C, from about 60°C to about 90°C, from about 60°C to about 89°C, from about 60°C to about 88°C, from about 60°C to about 87°C, from about 60°C to about 86°C, From about 60°C to about 85°C, from about 60°C to about 84°C, from about 60°C to about 83°C, from about 60°C to about 82°C, from about 60°C to about 81°C, from about 60°C to about 80°C, from about 60°C to about 79°C, from about 60°C to about 78°C, from about 60°C to about 77°C, from about 60°C to about 76°C, from about 60°C to about 75°C, from about 60°C to about 74°C, from about 60°C to about 73°C, from about 60°C to about 72°C, from about 60°C to about 71°C, from about 60°C to about 70°C, from about 60°C to about 69°C, from about 60°C to about 68°C, from about 60°C to about 67°C, from about 60°C to about 66°C, from about 60°C to about 65°C, from about 60°C to about 64°C, from about 60°C to about 63°C, from about 60°C to about 62°C, from about 60°C to about 61°C, about 40°C, about 41°C, about 42°C, about 43°C, about 44°C, about 45°C, about 46°C, about 47°C, about 48°C, about 49°C, about 50°C, about 51°C, about 52°C, about 53°C, about 54°C, about 55°C, about 56°C, about 57°C, about 58°C, about 59°C, about 60°C, about 61°C, about 62°C, about 63°C, about 64°C, about 65°C, about 66°C, about 67°C, about 68°C, about 69°C, about 70°C, about 71°C, about 72°C, about 73°C, about 74°C, about 75°C, about 76°C, about 77°C, about 78°C, about 79°C, about 80°C, about 81°C, about 82°C, about 83°C, about 84°C, about 85°C, about 86°C, about 87°C, about 88°C, about 89°C,The method is carried out at a temperature of about 90°C, about 91°C, about 92°C, about 93°C, about 94°C, about 95°C, about 96°C, about 97°C, about 98°C, about 99°C, about 100°C, or any range or value therebetween.

[0121] The method can be carried out at about 60°C to about 80°C, about 61°C to about 80°C, about 62°C to about 80°C, about 63°C to about 80°C, about 64°C to about 80°C, about 65°C to about 80°C, about 66°C to about 80°C, about 67°C to about 80°C, about 68°C to about 80°C, about 69°C to about 80°C, about 70°C to about 80°C, about 71°C to about 80°C, about 72°C to about 80°C, about 73°C to about 80°C, about 74°C to about 80°C, about 75°C to about 80°C, about 76°C to about 80°C 80°C, about 77°C to about 80°C, about 78°C to about 80°C, about 79°C to about 80°C, about 60°C to about 79°C, about 60°C to about 78°C, about 60°C to about 77°C, about 60°C to about 76°C, about 60°C to about 75°C, about 60°C to about 74°C, about 60°C to about 73°C, about 60°C to about 72°C, about 60°C to about 71°C, about 60°C to about 70°C, about 60°C to about 69°C, about 60°C to about 68°C, about 60°C to about 67°C, about 60°C to about 66°C ℃ , about 60 ℃ to about 65 ℃ , about 60 ℃ to about 64 ℃ , about 60 ℃ to about 63 ℃ , about 60°C to about 62°C, about 60°C to about 61°C, about 60°C, about 61°C, about 62°C, about 63°C, about 64°C, about 65°C, about 66°C, about 67°C, about 68°C, about 69°C, about 70°C, about 71°C, about 72°C, about 73°C, about 74°C, about 75°C, about 76°C, about 77°C, about 78°C, about 79°C, about 80°C, or any range or value therebetween.

[0122] The method can be carried out at a pH of about 4 to about 7, about 4 to about 6.5, about 4 to about 6, about 4 to about 5.5, about 4 to about 5, about 4 to about 4.5, about 4.5 to about 7, about 4.5 to about 6.5, about 4.5 to about 6, about 4.5 to about 5.5, about 4.5 to about 5, about 5 to about 7, about 5 to about 6.5, about 5 to about 6, about 5 to about 5.5, about 5.5 to about 7, about 5.5 to about 6.5, about 5.5 to about 6, about 6 to about 7, about 6 to about 6.5, about 5.5 to about 7, about 5.5 to about 6.5, about 5.5 to about 6, about 6 to about 7, about 6 to about 6.5, about 6.5 to about 7, or at most about 4, or at most about 4.5, or at most about 5, or at most about 5.5, at most about 6, at most about 6.5, at most about 7; or about 4, about 4.5, about 5, about 5.5, about 6, about 6.5, about 7, or any range or value therebetween.

[0123] The method can be performed for about 5 minutes to about 4 hours (about 240 minutes), about 5 minutes to about 240 minutes, about 5 minutes to about 235 minutes, about 5 minutes to about 230 minutes, about 5 minutes to about 225 minutes, about 5 minutes to about 220 minutes, about 5 minutes to about 215 minutes, about 5 minutes to about 210 minutes, about 5 minutes to about 205 minutes, about 5 minutes to about 200 minutes, about 5 minutes to about 195 minutes, about 5 minutes to about 190 minutes, about 5 minutes to about 185 minutes, about 5 minutes to about 180 minutes, about 5 minutes to about 175 minutes, about 5 minutes to about 170 minutes, about 5 minutes to about 165 minutes, about 5 minutes to about 160 minutes, about 5 minutes to about 155 minutes, about 5 minutes to about 15 0 minutes, about 5 minutes to about 145 minutes, about 5 minutes to about 140 minutes, about 5 minutes to about 135 minutes, about 5 minutes to about 130 minutes, about 5 minutes to about 125 minutes, about 5 minutes to about 120 minutes, about 5 minutes to about 115 minutes, about 5 minutes to about 110 minutes, about 5 minutes to about 105 minutes, about 5 minutes to about 100 minutes, about 5 minutes to about 95 minutes, about 5 minutes to about 90 minutes, about 5 minutes to about 85 minutes, about 5 minutes to about 80 minutes, about 5 minutes to about 75 minutes, about 5 minutes to about 70 minutes, about 5 minutes to about 65 minutes, about 5 minutes to about 60 minutes, about 5 minutes to about 55 minutes, about 5 minutes to about 50 minutes, about 5 minutes to about 45 minutes, about 5 minutes to about about 40 minutes, about 5 minutes to about 35 minutes, about 5 minutes to about 30 minutes, about 5 minutes to about 25 minutes, about 5 minutes to about 20 minutes, about 5 minutes to about 15 minutes, about 5 minutes to about 10 minutes, about 5 minutes to about 240 minutes, about 10 minutes to about 240 minutes, about 15 minutes to about 240 minutes, about 20 minutes to about 240 minutes, about 25 minutes to about 240 minutes, about 30 minutes to about 240 minutes, about 35 minutes to about 240 minutes, about 40 minutes to about 240 minutes, about 45 minutes to about 240 minutes, about 50 minutes to about 240 minutes, about 55 minutes to about 240 minutes, about 60 minutes to about 240 minutes, about 65 minutes to about 240 minutes, about 70 minutes to about 240 minutes minutes, about 75 minutes to about 240 minutes, about 80 minutes to about 240 minutes, about 85 minutes to about 240 minutes, about 90 minutes to about 240 minutes, about 95 minutes to about 240 minutes, about 100 minutes to about 240 minutes, about 105 minutes to about 240 minutes, about 110 minutes to about 240 minutes, about 115 minutes to about 240 minutes, about 120 minutes to about 240 minutes, about 125 minutes to about 240 minutes, about 130 minutes to about 240 minutes, about 135 minutes to about 240 minutes, about 140 minutes to about 240 minutes, about 145 minutes to about 240 minutes, about 150 minutes to about 240 minutes, about 155 minutes to about 240 minutes, about 160 minutes to about 240 minutes,about 165 minutes to about 240 minutes, about 170 minutes to about 240 minutes, about 175 minutes to about 240 minutes, about 180 minutes to about 240 minutes, about 185 minutes to about 240 minutes, about 190 minutes to about 240 minutes, about 195 minutes to about 240 minutes, about 200 minutes to about 240 minutes, about 205 minutes to about 240 minutes, about 210 minutes to about 240 minutes, about 215 minutes to about 240 minutes, about 220 minutes to about 240 minutes, about 225 minutes to about 240 minutes, about 230 minutes to about 240 minutes, about 235 minutes to about 240 minutes, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 25 minutes, about 30 minutes (about 0.5 hours), about 35 minutes, about 40 minutes, about 45 minutes, about 50 minutes, about 55 minutes, about 60 minutes (about 1 hour), about 65 minutes , about 70 minutes, about 75 minutes, about 80 minutes, about 85 minutes, about 90 minutes (about 1.5 hours), about 95 minutes, about 100 minutes, about 105 minutes, about 110 minutes, about 115 minutes, about 120 minutes (about 2 hours), about 125 minutes, about 130 minutes, about 135 minutes, about 140 minutes, about 145 minutes, about 150 minutes (about 2.5 hours), about 155 minutes, about 160 minutes, about 165 minutes, about 170 minutes, about 175 minutes, about 180 minutes (about 3 hours), about 185 minutes, about 190 minutes, about 195 minutes, about 200 minutes, about 205 minutes, about 210 minutes (about 3.5 hours), about 215 minutes, about 220 minutes, about 225 minutes, about 230 minutes, about 235 minutes, about 240 minutes (about 4 hours), or any range or value therebetween. ,

[0124] The present invention also relates to a current collector obtained by the method disclosed herein. The current collector may comprise aluminum, titanium, stainless steel foil and / or copper.

[0125] The present invention also relates to an electrode material obtained by the method disclosed herein. The present invention also relates to a binder / polymer binder obtained by the method disclosed herein.

[0126] Example

[0127] Non-limiting examples and comparative examples of the present invention will now be described in further detail by reference to specific examples, which should not be construed as limiting the scope of the present invention in any way.

[0128] Example 1: Procedure for preparing solvent

[0129] The solvent used in the present invention comprises cyclopentanone as a first component and carboxylic acid, ascorbic acid, alkyl-substituted urea or lactone as a second component.

[0130] Each solvent is formed by mixing the components together to form a homogeneous solution. Their compositions are shown in Table 1 below.

[0131] Table 1: Solvents used in the present invention

[0132]

[0133] 1 1,2,4,5-Benzenetetracarboxylic acid

[0134] Example 2: Characterization of solvents

[0135] Example 2a: Raman spectra of cyclopentanone and L-ascorbic acid / water (solvent 1)

[0136] The Raman spectrum of solvent 1 in Example 1 was obtained ( Figure 3 (b)) and mixed it with pure cyclopentanone (CP, Figure 2 and Figure 3 (c)), pure water ( Figure 3 (d)) and LA / water (weight ratio of 0.3 g / 3.6 g, Figure 3 (a)) for comparison. The peaks of solvent 1 correspond to the individual components, with a peak at about 3450 cm -1 The circled area at shows the water vibration band (-OH) corresponding to the presence of water. In the enlarged image, at about 1060 cm -1 The circled area at corresponds to the vibration band of L-ascorbic acid.

[0137] Example 2b: Raman spectra of cyclopentanone and 1,2,4,5-benzenetetracarboxylic acid / water (solvent 3)

[0138] Obtain the Raman spectrum of solvent 3 in Example 1 ( Figure 4 (a)), and mixed it with pure cyclopentanone (CP) ( Figure 2 and Figure 4 The peak of solvent 3 corresponds to the peak of pure CP at about 1500-1650 cm -1 There is another peak in the gray band region at , which corresponds to the peak of 1,2,4,5-benzenetetracarboxylic acid.

[0139] Example 2c: pH of the solvent

[0140] Using CP / water (weight ratio = 3 g / 0.9 g, I) and L-ascorbic acid / water (weight ratio = 0.3 g / 3.6 g, II) as control solvents, the solvents in Examples 1 (III) and 1c (IV) were measured using pH indicator strips and found to have a pH of about 4 ( Figure 5). The pH value of CP / water (weight ratio = 3 g / 0.9 g) was found to be about 4. The pH value of L-ascorbic acid / water (weight ratio = 0.3 g / 3.6 g) was found to be about 2.

[0141] Example 3: Method for recovering collected fluid

[0142] Example 3a: Pretreatment of waste batteries

[0143] First, the waste battery is completely discharged and maintained at a voltage of 0.5V for at least 24 hours. The waste battery is then disassembled and chopped with an insulating cutter to expose the cathode and anode. The exposed cathode is then cleaned with diethyl carbonate or dimethyl carbonate and further cut into pieces with a size of about 1 cm × 1 cm to 8 cm × 12 cm ( Figure 1 (a) and Figure 1 (b)).

[0144] Meanwhile, waste coatings from the battery manufacturing process were used directly in the subsequent examples ( Figure 1 (c)).

[0145] Example 3b: Recycling of collected fluid

[0146] Next, the electrode material is removed from the current collector of the cathode using the solvent in Example 1. The solvent in Example 1 is added to a container containing the cut cathode fragments at a weight / volume ratio of 1:20 g / mL, and then stirred continuously at a temperature of about 60°C-100°C at a speed of 500-1000 revolutions / minute (rpm) for a duration of about 0.5 hour to 1 hour. The polymer binder polyvinylidene fluoride (PVDF) is dissolved by the solvent, and the aluminum (Al) foil current collector is detached from the electrode material without any corrosion. The detached current collector is then filtered and washed with ethanol and then dried in an oven to obtain a fully recovered (100%) aluminum foil. The used solvent can be collected and reused for subsequent processing of a new batch of cut cathodes.

[0147] Example 4: Solubility properties of different solvents

[0148] Various solvents were tested following the general procedure described in Example 3b. The results and discussion for each solvent tested are listed in Table 2 and in the sub-examples that follow.

[0149] Table 2. Properties of different solvents

[0150]

[0151] Example 4a: Cyclopentanone and L-ascorbic acid / water (Solvent 1)

[0152] At a processing temperature of 60°C, solvent 1 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 2 minutes to 3 hours, depending on the condition of the spent battery or the amount of slurry coating present on top of the aluminum foil (Table 2, item 1). L-ascorbic acid acted as a reducing agent, allowing for better reduction of the cathode. The unique combination of components gave L-ascorbic acid good solubility in cyclopentanone.

[0153] To further demonstrate the effectiveness of the combination of CP and L-ascorbic acid relative to their individual components, further studies were conducted using CP / water (weight ratio: 3 g / 0.9 g) and L-ascorbic acid / water (0.3 g / 3.6 g) solvents.

[0154] Table 3: Studies on the effect of L-ascorbic acid

[0155] sample CP(g) L-Ascorbic acid (g) Water(g) LA(Solvent 1) 3 0.3 0.6 LA-3 3 - 0.9 LA-4 - 0.3 3.6

[0156] Photos showing the recycling process Fig.16 (2 minutes later), Fig.17 (5 minutes later), Fig.18 (20 minutes later) and Fig.19 (After 1.5 hours).

[0157] like Fig.16 As shown, the coating in sample LA was successfully stripped from the current collector after 2 minutes, however, no obvious changes were observed for samples LA-3 and LA-4.

[0158] like Fig.17 As shown, after 5 minutes, for sample LA-4 (left), the surface of the coating begins to swell, while for sample LA-3 (right), there is still no obvious change.

[0159] like Fig.18 As shown in Figure 1, the active material in the coating of sample LA has been separated from the conductive carbon, while the aluminum foil remains intact after 20 minutes. Meanwhile, the coating on the current collector of sample LA-3 only shows pits. Only a portion of the coating in sample LA-4 is separated from the current collector surface.

[0160] like Fig.19 As shown, the separation of carbon and active material in sample LA can be clearly observed. Even after 1.5 hours, the surface of the aluminum foil is clean and no corrosion area is observed. At the same time, most of the coating on the current collector of sample LA-3 is still there. And part of the coating in sample LA-4 has been peeled off from the current collector surface.

[0161] Example 4b: Cyclopentanone and Succinic Acid / Water (Solvent 2)

[0162] At a processing temperature of 60° C., solvent 2 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 2 hours (Table 2, entry 2). Succinic acid acted as a leaching agent, dissolving the transition metal ions.

[0163] Example 4c: Cyclopentanone and 1,2,4,5-benzenetetracarboxylic acid (Solvent 3)

[0164] At a processing temperature of 60°C, solvent 3 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 10 minutes to 2 hours, depending on the condition of the spent battery or the amount of coating present on top of the aluminum foil (Table 2, entry 3). Pyromellitic acid (1,2,4,5-benzenetracarboxylic acid) has the ability to form hydrogen bonds, thereby improving the efficiency of removing the electrode from the current collector.

[0165] Example 4d: Cyclopentanone and malonic acid (solvent 4)

[0166] At a processing temperature of 80 °C, solvent 4 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 3 hours (Table 2, entry 4). As a dicarboxylic acid, malonic acid acts as a chelating agent and can form stable chelates with heavy metals, thereby improving the efficiency of removing electrodes from the current collector.

[0167] Example 4e: Cyclopentanone and sebacic acid (Solvent 5)

[0168] At a processing temperature of 80 °C, solvent 5 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 4 hours (Table 2, entry 5). Similar to malonic acid, sebacic acid is a dicarboxylic acid that acts as a chelating agent and can form stable chelates with heavy metals, thereby improving the efficiency of electrode removal from the current collector.

[0169] Example 4f: Cyclopentanone and tetramethylurea (TMU) (Solvent 6)

[0170] At a processing temperature of 60° C., solvent 6 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 1.5 hours (Table 2, entry 6). TMU has good surfactant properties, which significantly improves the efficiency of removing the electrode from the current collector.

[0171] Example 4g: Cyclopentanone and γ-butyrolactone (Solvent 7)

[0172] At a processing temperature of 60 °C, solvent 7 was able to dissolve the polymer binder and recover the aluminum foil current collector in about 1 hour (Table 2, entry 7).

[0173] To further demonstrate the effectiveness of γ-butyrolactone as an additive, solvent 7 ( Fig. 20 ).

[0174] like Fig. 20As shown, the presence of γ-butyrolactone in CP improves the efficiency of electrode removal from the current collector compared to pure CP or pure γ-butyrolactone.

[0175] Example 5: Recycled Current Collector

[0176] Example 5a: Characterization

[0177] The elemental composition and crystal structure of the recycled aluminum current collector were characterized using scanning electron microscopy (SEM) combined with electron dispersive X-ray spectrometer (EDS) (JEOL FESEM7600F) and X-ray diffractometer (Bruker D8 Advance, XRD), respectively. The X-ray diffraction pattern was analyzed based on the Inorganic Crystal Structure Database (ICSD) using Match! software. The results showed that the recycled aluminum current collector was composed of aluminum elements without any traces of other transition metal ions from battery materials on its surface (e.g., nickel, manganese, or cobalt content from the cathode) ( Figure 6-Figure 8 ), which is consistent with the XRD results ( Fig. 9 ) are highly consistent.

[0178] The Raman spectra of the recycled aluminum were also compared with those of new (virgin) aluminum ( Fig.14 ). The results showed that the recycled aluminum had no residual active materials on the surface, which proved that the aluminum was successfully recovered.

[0179] Example 5b: Application of Recycled Current Collector

[0180] A coin cell configuration was assembled using Prussian blue analog (PBA) as the cathode and a recycled aluminum current collector as the anode to test the feasibility of recycled aluminum as an energy source for rechargeable energy storage applications ( Fig.10 ). Whatman glass fiber was used as a spacer and 2 m (mol kg -1 ) aluminum trifluoromethanesulfonate (AlTFS) as electrolyte. At 25 mA g -1 The assembled battery exhibited excellent electrochemical cycling stability when cycled between 1.6 V and 0.6 V at a current density of Fig.11 ), and its energy density is 52.4Wh·kg -1 , higher than the latest lead-acid batteries (about 40Wh·kg -1 ).exist Fig.12 The reversible redox process of the prototype battery is shown in FIG.

[0181] The scalability of the direct recycling approach has also been demonstrated in the application of waste coatings. As a validation of the concept, recycled aluminum was used as a current collector for lithium-ion batteries (LIBs). Using a typical battery slurry coating method, the cathode slurry was prepared with 80wt% NMC622, 10wt% Super C65 conductive carbon, and 10wt% HSV1810 binder, and then stirred in 1-methyl-2-pyrrolidone (NMP) for at least 5 hours. The slurry was then coated onto the recycled aluminum current collector and dried in a convection oven at 80°C for at least 1 hour. The electrode coating was then dried and degassed in a vacuum oven overnight. Circular electrodes with a diameter of 12 mm were punched out and assembled into button cells. Celgard 2400 was used as a separator, lithium foil was used as a counter electrode, and 1M LiPF in ethylene carbonate (EC): ethyl methyl carbonate (EMC) (3:7v / v) was used. 6 As electrolyte. On a NEWARE battery tester, the charge rate was 1C (1C = 160 mA g -1 ) The battery was electrochemically tested. Compared with the battery using the new aluminum foil as the current collector ( Fig.13 ), the battery using recycled aluminum foil exhibited comparable electrochemical performance and high Coulombic efficiency due to the good contact between the new electrode material and the recycled aluminum foil.

[0182] The above results show that the aluminum foil is not changed during the recycling process of the present invention, and also show that the recycled aluminum foil can be further used in new battery applications without affecting its performance. This illustrates the practicality of the method of recycling collected fluid for energy storage applications of the present invention.

[0183] Example 6: Recycling fluid from batteries

[0184] To further demonstrate the commercial feasibility of the present invention, the method was tested on spent batteries.

[0185] For this purpose, used batteries were obtained from electronic waste collected at Nanyang Technological University, Singapore.

[0186] The waste batteries are then shredded using a battery shredder. A photograph of the processed waste batteries is shown in FIG21 .

[0187] Example 6a: Recycling of collected fluid

[0188] The waste battery was immersed in solvent 3 of Table 1 (cyclopentanone: L-ascorbic acid: water = 3 g: 0.3 g: 0.6 g), and was subjected to the recovery conditions in Example 3b.

[0189] exist Fig. 22 A photograph showing the recycling process is shown in . It can be seen from the photograph that as the reaction proceeds, the coating is gradually peeled off from the current collector.

[0190] After stirring, the spent batteries were filtered out from the solvent. Fig.23 (a) shows the presence of aluminum foil. Fig.23 As shown in (b), after cleaning, the surface of the recovered aluminum is clean, indicating that the coating was successfully removed.

[0191] Example 6b: Recovery of electrode materials, binders, active materials and carbon

[0192] Fig.24 The remaining solution after separation of the current collector is shown. It can be observed that there is a black residue on the upper surface of the solution and a gray precipitate at the bottom. These indicate the successful recovery of carbon black and active materials, respectively.

[0193] Industrial Applicability

[0194] The present invention relates to a solvent for dissolving an adhesive and a method for recovering a fluid from a battery, capacitor or waste paint. The present disclosure also relates to a current collector obtained by the method, and a battery comprising the recovered current collector. The solvent disclosed herein is environmentally friendly and harmless, which eliminates the need for high energy input using conventional strong acids or pyrometallurgical methods in leaching, and may not require a large number of post-processing steps to recover the fluid. In addition, the disclosed method for recovering a fluid from a battery or capacitor may be cost-effective, simple, environmentally friendly and scalable in a large-scale manufacturing process.

[0195] Obviously, various other modifications and adjustments to the present invention will be apparent to those skilled in the art after reading the foregoing disclosure without departing from the spirit and scope of the invention, and all such modifications and adjustments fall within the scope of the appended claims.

Claims

1. A solvent for dissolving an adhesive, the solvent comprising: (i) cyclopentanone as a first component; and (ii) Carboxylic acid, ascorbic acid, alkyl-substituted urea or lactone as the second component.

2. The solvent of claim 1, wherein the first component and the second component have a weight ratio of about 1:1 to about 60:

1.

3. The solvent of claim 1 or 2, wherein the first component and the second component have a weight ratio of about 10:1 to about 30:

1.

4. The solvent according to any one of claims 1 to 3, wherein the carboxylic acid is C2-C 12 Dicarboxylic acids, C3-C 12 Tricarboxylic acid or C4-C 12 Tetracarboxylic acid.

5. The solvent according to any one of claims 1 to 4, wherein the dicarboxylic acid is selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, 1,4-cyclohexanedicarboxylic acid and sebacic acid.

6. The solvent according to any one of claims 1 to 5, wherein the tricarboxylic acid is selected from the group consisting of ethane-1,1,1-tricarboxylic acid, 1,1,2-hydrazinetricarboxylic acid, prop-1-ene-1,2,3-tricarboxylic acid, 2-oxoethane-1,1,2-tricarboxylic acid, ethylene oxide-2,2,3-tricarboxylic acid, 2-hydroxypropane-1,2,3-tricarboxylic acid (citric acid), prop-1-ene-1,2,3-tricarboxylic acid (aconitic acid) and propane-1,2,3-tricarboxylic acid.

7. The solvent according to any one of claims 1 to 6, wherein the tetracarboxylic acid is selected from the group consisting of 1,2,4,5-benzenetetracarboxylic acid and ethylenetetracarboxylic acid.

8. The solvent according to any one of claims 1 to 7, wherein the alkyl-substituted urea is selected from the group consisting of methyl urea, dimethyl urea, trimethyl urea, tetramethyl urea, diethyl urea, tetraethyl urea and propyl urea.

9. The solvent according to any one of claims 1 to 8, wherein the lactone is selected from the group consisting of γ-butyrolactone, ε-caprolactone and D-glucono-δ-lactone.

10. The solvent according to any one of claims 1 to 9, wherein the solvent further comprises water.

11. The solvent according to any one of claims 1 to 10, wherein the solvent comprises: (i) cyclopentanone as a first component; and (ii) L-succinic acid, 1,2,4,5-pyromellitic acid, malonic acid, sebacic acid, L-ascorbic acid, tetramethylurea or γ-butyrolactone as the second component.

12. The solvent according to any one of claims 1 to 11, wherein the solvent comprises: (i) cyclopentanone as a first component; and (ii) L-succinic acid, 1,2,4,5-pyromellitic acid, malonic acid, sebacic acid, L-ascorbic acid or tetramethylurea as a second component, wherein the weight ratio of the first component to L-succinic acid, 1,2,4,5-benzenetetracarboxylic acid, malonic acid, sebacic acid, L-ascorbic acid or tetramethylurea is from about 30:1 to about 10:1, or The weight ratio of the first component to γ-butyrolactone is about 1:

1.

13. A method for recovering a current collector from a battery, a capacitor or waste paint comprising an electrode material, a current collector and a binder, the method comprising adding the disassembled battery or capacitor or the waste paint to the solvent according to any one of claims 1 to 12.

14. The method of claim 13, wherein the method is performed at a temperature of about 60°C to about 100°C.

15. The method of claim 13 or 14, wherein the method is carried out at a temperature of about 60°C to about 80°C.

16. The method of claim 15, wherein the method is performed at a pH of about 3 to about 7.

17. The method according to any one of claims 13 to 16, wherein the method is performed for a duration of about 5 minutes to about 4 hours.

18. The method of any one of claims 13 to 17, wherein the current collector comprises aluminum, titanium, stainless steel foil, or copper.

19. A current collector obtained by the method according to any one of claims 13 to 18.

Images