CN113293000B - Stripping reagent and stripping method of secondary battery diaphragm coating - Google Patents
Stripping reagent and stripping method of secondary battery diaphragm coating Download PDFInfo
- Publication number
- CN113293000B CN113293000B CN202110569671.XA CN202110569671A CN113293000B CN 113293000 B CN113293000 B CN 113293000B CN 202110569671 A CN202110569671 A CN 202110569671A CN 113293000 B CN113293000 B CN 113293000B
- Authority
- CN
- China
- Prior art keywords
- coating
- stripping
- separator
- diaphragm
- stripping agent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K13/00—Etching, surface-brightening or pickling compositions
- C09K13/02—Etching, surface-brightening or pickling compositions containing an alkali metal hydroxide
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K13/00—Etching, surface-brightening or pickling compositions
Abstract
The application relates to the field of batteries, in particular to a stripping reagent and a stripping method of a secondary battery diaphragm coating. The stripping agent comprises the following components: the solubility parameter is 15 (J/cm)3)1/2‑30(J/cm3)1/2An organic solvent and a base; the alkali accounts for 0.0001-8% of the total mass of the stripping reagent. The application provides a stripping agent can peel off battery diaphragm coating, makes coating and diaphragm separation, can separate coating and diaphragm completely at the in-process of separation, and can avoid causing the harm to the diaphragm, is unfavorable for the performance of accurate analysis coating and diaphragm.
Description
Technical Field
The application relates to the field of batteries, in particular to a stripping reagent and a stripping method of a secondary battery diaphragm coating.
Background
The diaphragm is an important structure in the secondary battery, the safety of the diaphragm is one of the key factors of the safety of the lithium ion power battery, and the microporous membrane using polypropylene and polyethylene as raw materials can not meet the requirement, so the coating film becomes the main development direction, the performance of the diaphragm is obviously improved by coating different materials on the surface of the polyolefin diaphragm, such as coating ceramic particles to improve the heat resistance, thermal stability and wettability, coating polymer particles to improve the adhesion of a pole piece, and the like.
The study of coated films has also become of particular importance, especially in the analysis of coatings and membranes. However, in the field of battery separators, the coating is very thin (micron-sized) and difficult to form a film, and the coating cannot be directly peeled off, so that a technical means for well separating the coating from the separator is not provided at present.
Disclosure of Invention
An object of the embodiments of the present application is to provide a stripping agent, a stripping method of a coating layer of a separator of a secondary battery, which aims to separate the coating layer and the separator relatively well.
The application provides a stripping reagent, which comprises the following components:
the solubility parameter is 15 (J/cm)3)1/2-30(J/cm3)1/2An organic solvent and a base; the alkali accounts for 0.0001-8% of the total mass of the stripping reagent.
The application provides a stripping agent can peel off battery diaphragm coating, makes coating and diaphragm separation, can separate coating and diaphragm completely at the in-process of separation, and can avoid causing the harm to the diaphragm, is unfavorable for the performance of accurate analysis coating and diaphragm.
In some embodiments herein, the organic solvent is selected from at least one of acetone, cyclohexanone, cyclohexane, benzene, toluene, xylene, propanol, ethyl acetate, N-methyl-2-pyrrolidone, and dimethyl sulfoxide.
In some embodiments herein, the organic solvent is benzene and benzyl alcohol in a mass ratio of (2-5): 1;
optionally, the organic solvent is benzene and acetone in a mass ratio of (6-8): 1;
optionally, the organic solvent is toluene and dimethyl sulfoxide in a mass ratio of (4-7): 1.
Benzene and benzyl alcohol with the mass ratio of (2-5):1, benzene and acetone with the mass ratio of (6-8):1 or toluene and dimethyl sulfoxide with the mass ratio of (4-7):1 are selected as organic solvents, a stripping reagent obtained after the organic solvents are mixed with an alkali solution can completely strip the coating, a diaphragm obtained after stripping is complete, and the coating and the stripping reagent are easy to remove after stripping is completed, so that later-stage treatment and analysis are facilitated.
In some embodiments herein, the base comprises 0.0001% to 5% of the total mass of the stripping agent;
optionally, the stripping reagent further comprises water, and the water accounts for 0.0006% -20% of the total mass of the stripping reagent.
In some embodiments of the present application, the stripping agent is formed by mixing essentially the following components:
the solubility parameter is 15 (J/cm)3)1/2-30(J/cm3)1/2And an alkali solution with a concentration of 0.1 wt% to 20 wt%; the alkali solution accounts for 0.1-40 wt% of the total mass of the raw materials of the stripping reagent;
optionally, the concentration of the alkali solution is 0.1 wt% to 18 wt%.
In some embodiments of the present application, the alkali solution is a metal oxide solution.
In some embodiments herein, the alkaline solution is selected from at least one of potassium hydroxide, sodium hydroxide, and lithium hydroxide.
The application also provides a stripping method of the secondary battery diaphragm coating, which comprises the following steps:
the secondary battery separator supporting the coating layer was placed in the above-mentioned stripping agent, and the separator and the coating layer were separated by stirring.
In some embodiments of the present application, the step of agitating the separation membrane and the coating comprises: separating the membrane from the coating layer by ultrasonic treatment at 20-80 ℃ for 0.5-4 h.
In some embodiments of the present application, the material of the separator is selected from at least one of polyethylene, polypropylene, polybutylene, polypentylene, and polyethylene terephthalate; the material of the coating comprises a polymer or a ceramic;
optionally, the material of the coating comprises at least one of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene-alumina ceramic, and polymethyl methacrylate and derivatives thereof; alternatively, the material of the coating comprises at least one of alumina, boehmite, attapulgite, silica, titania, magnesia, zirconia, and silicon carbide.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.
Fig. 1 shows an SEM image of the separator peeled by the peeling method of example 1 of the present application.
Fig. 2 shows an SEM image of the separator peeled by the peeling method of example 2 of the present application.
Fig. 3 shows an SEM image of the separator peeled by the peeling method of example 3 of the present application.
Fig. 4 shows an SEM image of the separator peeled by the peeling method of example 4 of the present application.
Fig. 5 shows an SEM image of the separator peeled by the peeling method of comparative example 1 of the present application.
Fig. 6 shows an SEM image of the separator peeled by the peeling method of comparative example 2 of the present application.
Fig. 7 shows an SEM image of the separator peeled by the peeling method of comparative example 3 of the present application.
Fig. 8 shows an SEM image of the separator peeled by the peeling method of comparative example 4 of the present application.
Fig. 9 shows an SEM image of the separator peeled by the peeling method of comparative example 5 of the present application.
Fig. 10 shows an SEM image of the separator peeled by the peeling method of comparative example 6 of the present application.
Fig. 11 shows an SEM image of the separator peeled by the peeling method of comparative example 7 of the present application.
In fig. 1 to 3 and 9 to 11, Mag of the electronic scanning mirror is 5.0KX, and the magnification is 5 KX.
In fig. 4 and 5, Mag of the electronic scanning mirror is 2.0KX, and the magnification is 2 KX.
In fig. 6 to 8, Mag of the electronic scanning mirror is 10.0KX, and the magnification is 1 ten thousand times.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The separator is one of the key internal layer components of a lithium battery. The positive electrode and the negative electrode of the battery are separated by the diaphragm, electrolyte ions pass through the diaphragm, the capacity, the cycle performance, the safety performance and other characteristics of the battery are directly influenced by the diaphragm, and the physical and chemical properties of the diaphragm have great influence on the performance of the battery.
Coating on the surface of the separator is an effective method for improving the safety of the separator. For example, the ceramic material coating on the surface of the diaphragm can improve the heat resistance and the mechanical strength of the diaphragm; for example, the PVDF coating layer can be combined with an electrolyte in a lithium ion battery to form a stable gel conductive polymer, so that the performance of the lithium ion battery is remarkably improved.
But the performance of the coating layer also directly affects the internal resistance of the lithium battery, the thickness of the separator, and the conduction of lithium ions. In this regard, analysis of the coated coating and the separator during coating of the separator is of great importance, and only clear and accurate analysis of the separator and the coating is beneficial to better adjustment of the separator performance.
The present application provides a stripping agent and a stripping method.
The stripping agent and the stripping method of the secondary battery separator coating according to the examples of the present application will be specifically described below.
The stripping agent mainly comprises the following components:
the solubility parameter is 15 (J/cm)3)1/2-30(J/cm3)1/2An organic solvent and a base; the alkali accounts for 0.0001-8% of the total mass of the stripping reagent.
For example, the base is 0.0001%, 0.0002%, 0.0005%, 0.0008%, 0.001%, 0.003%, 0.007%, 0.009%, 0.01%, 0.06%, 0.1%, 0.8%, 1%, 1.5%, 2.3%, 4%, 4.3%, 5.6%, 6.1%, 6.8%, 7%, 8% of the total mass of the exfoliating agent.
The application provides a stripping agent can peel off battery diaphragm coating, makes coating and diaphragm separation, can separate coating and diaphragm completely at the in-process of separation, and can avoid causing the harm to the diaphragm, is unfavorable for the performance of accurate analysis coating and diaphragm.
The solubility parameter of the organic solvent is 15 (J/cm)3)1/2-30(J/cm3)1/2In the present application, a solubility parameter of 15 (J/cm) is selected3)1/2-30(J/cm3)1/2Organic solvents within the range.
As an example, the organic solvent may be at least one of acetone, cyclohexanone, cyclohexane, benzene, toluene, xylene, propanol, ethyl acetate, N-methyl-2-pyrrolidone, and dimethyl sulfoxide.
Illustratively, the organic solvent is benzene and benzyl alcohol in a mass ratio of (2-5):1, for example, benzene and benzyl alcohol in a mass ratio of 2:1, 2.2:1, 2.4:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, 3:1, 3.5:1, 4.6:1, 5:1, and so forth.
Illustratively, the organic solvent is benzene and acetone in a mass ratio of (6-8): 1; for example, the mass ratio of benzene to acetone is 6:1, 6.2:1, 6.5:1, 6.8:1, 7:1, 7.2:1, 7.5:1, 7.8:1, 9:1, and so forth.
Illustratively, the organic solvent is toluene and dimethyl sulfoxide in a mass ratio of (4-7): 1; for example, the mass ratio of toluene to dimethylsulfoxide is 4:1, 4.2:1, 4.4:1, 4.5:1, 4.7:1, 4.8:1, 4.9:1, 5.0:1, 5.3:1, 5.6:1, 5.9:1, 6.2:1, 6.6:1, 6.9:1, 7:1, and so forth.
Benzene and benzyl alcohol with the mass ratio of (2-5):1, benzene and acetone with the mass ratio of (6-8):1 or toluene and dimethyl sulfoxide with the mass ratio of (4-7):1 are selected as organic solvents, a stripping reagent obtained after the organic solvents are mixed with an alkali solution can completely strip the coating, a diaphragm obtained after stripping is complete, and the coating and the stripping reagent are easy to remove after stripping is completed, so that later-stage treatment and analysis are facilitated.
In some embodiments of the present application, the stripping agent further comprises water, the water comprising 0.0006% to 20% of the total mass of the stripping agent. For example, water comprises 0.0006%, 0.0008%, 0.001%, 0.003%, 0.009%, 0.02%, 0.05%, 0.08%, 0.1%, 0.6%, 1%, 3%, 4%, 6%, 8%, 11%, 14%, 16%, 17%, 19%, 19.8%, 20%, etc., of the total mass of the stripping agent.
The stripping agent also comprises water, the water and the organic solvent form an oil-water mixture, the oil-water mixture can enter the pore structure of the diaphragm more easily, and then the coating material with the microporous structure is stripped through the organic solution and the alkaline solution.
In some embodiments of the present application, the stripping agent may be free of water; the stripping agent may be other hydrophilic solvents, such as ethanol, methanol, etc., and may also enter the pore structure of the membrane more easily. Illustratively, in some embodiments of the present application, the stripping agent is formed by mixing essentially the following components:
the solubility parameter is 15 (J/cm)3)1/2-30(J/cm3)1/2And an alkali solution having a concentration of 0.1 wt% to 20 wt%; the alkaline solution accounts for 0.1-40 wt% of the total mass of the stripping reagent raw materials.
The concentration of the alkali solution is 0.1-20 wt%; in some embodiments, the concentration of the alkali solution is 0.1 wt% to 18 wt%; for example, the concentration of the alkali solution may be 0.1 wt%, 0.2 wt%, 0.7 wt%, 1 wt%, 1.5 wt%, 2.3 wt%, 3.5 wt%, 4.2 wt%, 5.4 wt%, 6.4 wt%, 7.3 wt%, 8.7 wt%, 9.3 wt%, 10.6 wt%, 12 wt%, 14 wt%, 17 wt%, 19 wt%, 20 wt%, and so forth.
The alkaline solution accounts for 0.1-40 wt% of the total mass of the stripping reagent raw materials, and the alkaline solution accounts for 0.1-25 wt% of the total mass of the stripping reagent raw materials. For example, the alkali solution accounts for 0.1 wt%, 0.5 wt%, 1.3 wt%, 2.6 wt%, 3.5 wt%, 4.6 wt%, 5.3 wt%, 6.7 wt%, 8 wt%, 11 wt%, 13 wt%, 16 wt%, 19 wt%, 21 wt%, 23 wt%, 27 wt%, 32 wt%, 36 wt%, 37 wt%, 38 wt%, 39 wt%, 40 wt%, etc. of the total mass of the raw materials of the stripping agent.
In some embodiments, the step of disposing the stripping agent comprises disposing the alkaline solution and then adding the organic agent.
The battery diaphragm is provided with a microporous structure, a part of coating materials enter the microporous structure after a coating is coated on the surface of the diaphragm, PP or PE materials of the diaphragm are hydrophobic and oleophilic materials, and only an alkaline solution is not capable of ensuring that the coating in the microporous structure of the diaphragm can be stripped, so that alkaline substances are ensured to be fully dissolved in solvents such as water or alcohol water to prepare an alkaline solution, then the alkaline solution is mixed into an organic reagent to form an oil-water mixture, the oil-water mixture formed in the coating stripping process can more easily enter the porous structure of the diaphragm, the coating materials of the microporous structure are better stripped through the organic solution and the alkaline solution, the content of the alkaline solution is not high enough and is less than or equal to 40 wt%, and therefore the oil-water mixture mainly containing oil can be ensured to be formed. In addition, no matter the coating is a hydrophilic ceramic coating or an oleophilic polymer coating, the formed oil-water mixture can well penetrate through the coating and enter the microporous structure of the diaphragm, and the coating is well stripped from the surface of the diaphragm and the coating in the microporous structure.
Illustratively, the alkali solution is a metal oxide solution, such as potassium hydroxide, sodium hydroxide, lithium hydroxide, and the like.
In other embodiments of the present application, the alkaline solution may be, for example, ammonia, ammonium salts, baking soda, sodium carbonate, and other alkaline solutions.
Illustratively, the solute in the alkali solution is a metal oxide and the solvent is water, ethanol, or an aqueous ethanol solution.
The polymer coating is simpler in composition than the ceramic coating, the polymer coating comprising one or more polymers and having a selected solubility parameter of 15 (J/cm)3)1/2-30(J/cm3)1/2The organic solvent can strip most of polymers from the surface of the diaphragm, but because certain reaction can occur among polymer molecular chains after the sizing agent is coated on the surface of the diaphragm and dried, the polymer molecular chains are mutually crosslinked and entangled, so that the solvent capable of dissolving the sizing agent is difficult to completely dissolve after coating and drying in the process of preparing the sizing agent, and the alkali solution can completely and cleanly strip the coating by matching with the organic solvent. By controlling the concentration and the content of the alkaline solution, the phenomenon that the membrane layer structure is damaged due to too strong alkalinity can be avoided, and therefore the coating is completely separated from the membrane layer under the condition that the membrane is not damaged. For coatings with more complex compositions such as ceramics, some reaction may occur during the coating preparation phase, e.g. drying, so that the coating is not easily separated from the separator during the stripping processFrom, the organic solvent that this application provided and the compatibility of alkali solution can be better with both separation, and can avoid introducing too much other composition and make the ceramic coating mixed liquid composition after peeling off more complicated.
In some embodiments of the present application, the stripping agent is prepared from a material having a solubility parameter of 15 (J/cm)3)1/2-30(J/cm3)1/2The alkali solution accounts for 0.1-40 wt% of the total mass of the raw materials of the stripping reagent, and the balance is the organic solvent. In other words, the stripping agent consists only of a solubility parameter of 15 (J/cm)3)1/2-30(J/cm3)1/2And an alkali solution. In some other embodiments of the present application, the raw material in the stripping agent may also include other components.
The application also provides a stripping method of the secondary battery diaphragm coating, which comprises the following steps:
the secondary battery separator supporting the coating layer was placed in the above-mentioned stripping agent, and the separator and the coating layer were separated by stirring.
Further, a separator of a secondary battery is covered with the stripping agent; stirring is carried out, and the diaphragm and the coating are separated after the stirring is finished.
In some embodiments of the present application, the agitation is performed ultrasonically. For example, soaking the secondary battery diaphragm loaded with the coating in the stripping reagent, and then carrying out ultrasonic treatment for 0.5-4 h; the frequency of the ultrasonic wave is more than or equal to 40KHZ, for example, the time of the ultrasonic wave can be 0.5h, 0.7h, 1h, 2h, 3h, 4h and the like.
In the examples of the present application, the peeling process may be performed at room temperature (20 to 30 ℃) or may be performed by heating to a predetermined temperature (e.g., 20 to 80 ℃). For example, in some embodiments, the stripping reagent and the coated membrane placed at 20-80 degrees C under ultrasonic stirring, temperature for example can be 20 degrees, 23 degrees, 25 degrees, 27 degrees, 29 degrees, 31 degrees, 35 degrees, 45 degrees, 51 degrees, 52 degrees, 57 degrees, 65 degrees, 70 degrees, 74 degrees, 79 degrees or 80 degrees C.
It should be noted that in some other embodiments of the present application, the stirring may not be performed under ultrasonic conditions, for example, the stirring may be performed directly by using a stirring rod.
As an example, the present application partially exemplifies materials of the separator and the coating layer, for example, the material of the separator may be polyethylene, polypropylene, polybutylene, polypentylene, polyethylene terephthalate, or the like; the material of the coating can be a polymer or ceramic coating, the polymer coating comprises polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene, polymethyl methacrylate and derivatives thereof, and the like, and the ceramic coating comprises aluminum oxide, boehmite, attapulgite, silicon oxide, titanium oxide, magnesium oxide, zirconium dioxide, silicon carbide and the like. The stripping agent provided by the application can be used for stripping the coating of the material and the diaphragm of the material.
In other embodiments of the present application, the stripping agent of the present application may also be applied to other membrane materials and other coating materials, for example, the membrane material may also be polyvinylidene fluoride (PVDF), cellulose composite membrane, and the like.
The stripping method provided by the embodiment of the application has at least the following advantages:
the stripping method provided by the application can better strip the coating from the surface of the diaphragm, can not cause great damage to the diaphragm after stripping, and can completely retain the diaphragm, thereby being beneficial to accurately analyzing the performances of the diaphragm and the coating in the later stage.
The features and properties of the present application are described in further detail below with reference to examples.
Examples 1 to 9, comparative examples 1 to 7
Examples 1 to 9 and comparative examples 1 to 7 each provide a coating peeling method comprising the steps of:
preparing a stripping reagent: mixing the solute and the solvent to prepare an alkali solution, and mixing the alkali solution and the organic solvent.
Taking the coating film to be stripped, flattening the coating film, placing the coating film in a stripping agent, wherein the stripping agent needs to completely cover the surface of the coating film, and then carrying out ultrasonic treatment.
The material ratios and coating materials used in the comparative examples and comparative methods are shown in tables 1 and 2, and in table 1, the ratio in the organic solvent is a mass ratio, and the coating and separator after stripping of the stripping agent are shown in table 2.
TABLE 1
TABLE 2
In Table 1, the solubility parameters of propionitrile, formamide, trichlorotrifluoroethane and pentanes are not 15 (J/cm)3)1/2-30(J/cm3)1/2Within the range.
Fig. 1 shows an SEM image of the separator peeled by the peeling method of example 1 of the present application.
Fig. 2 shows an SEM image of the separator peeled by the peeling method of example 2 of the present application.
Fig. 3 shows an SEM image of the separator peeled by the peeling method of example 3 of the present application.
Fig. 4 shows an SEM image of the separator peeled by the peeling method of example 4 of the present application.
As can be seen from fig. 1-4, there was little residual coating on the surface of the separator, and the pores on the surface of the separator were intact and not broken.
Fig. 5 shows an SEM image of the separator peeled by the peeling method of comparative example 1 of the present application. As can be seen from fig. 5, there was almost no residual coating on the surface of the diaphragm, but the surface of the diaphragm was damaged, forming barbed fibers.
Fig. 6 shows an SEM image of the separator peeled by the peeling method of comparative example 2 of the present application. As can be seen from fig. 6, the surface of the separator had a residual coating, and the surface of the separator was damaged, and the surface of the separator was seriously damaged.
Fig. 7 shows an SEM image of the separator peeled by the peeling method of comparative example 3 of the present application. As can be seen from fig. 7, the surface of the membrane had a residual coating and was intact.
Fig. 8 shows an SEM image of the separator peeled by the peeling method of comparative example 4 of the present application. As can be seen from fig. 8, the surface of the diaphragm had a residual coating, and the surface of the diaphragm was damaged, and the basic shape of the diaphragm was damaged.
Fig. 9 shows an SEM image of the separator peeled by the peeling method of comparative example 5 of the present application. As can be seen from fig. 9, a large amount of coating remains on the surface of the diaphragm, and the surface of the diaphragm is damaged, and the basic shape of the diaphragm is damaged.
Fig. 10 shows an SEM image of the separator peeled by the peeling method of comparative example 6 of the present application. As can be seen from fig. 10, a small amount of coating remained on the surface of the separator, and the surface of the separator was intact.
Fig. 11 shows an SEM image of the separator peeled by the peeling method of comparative example 7 of the present application. As can be seen from fig. 11, a small amount of coating remained on the surface of the separator, and the surface of the separator was intact.
As can be seen from table 1 and table 2 and fig. 1 to fig. 11, the methods provided in examples 1 to 6 of the present application can separate the coating from the separator more completely, and the structure of the separator is still more complete after separation. In comparative example 1, the content of the alkali solution was high, resulting in the surface of the separator being damaged; in comparative example 2, the malononitrile selected in the organic solvent did not completely peel off the coating; in comparative example 3, no alkali solution was used, the coating remained a lot, and the separator surface was intact.
In comparative example 4, the formamide selected for use in the organic solvent did not completely strip the coating; in comparative example 5, the large content of the alkali solution caused the damage of both the surface and the basic shape of the separator.
In comparative example 6 and comparative example 7, the organic solvent solubility parameter 14.9 of comparative example 6 and the main component, i.e., the pentan solubility parameter 12.9 of comparative example 7 were both less than 15, and the peeling effect on the coating was not good, resulting in coating residue.
The embodiment of the application can completely separate the coating film coating from the diaphragm under the condition of not damaging the diaphragm; the application provides a strip reagent composition simple, and the easy coating composition of strip coating back reagent composition distinguishes and gets rid of easily, conveniently carries out composition analysis, and the coating is peeled off effectually.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (11)
1. A stripping agent, characterized in that the stripping agent essentially comprises the following components:
the solubility parameter is 15 (J/cm)3)1/2-30(J/cm3)1/2And an alkali solution having a concentration of 0.1 wt% to 20 wt%; the alkali solution accounts for 0.1-40 wt% of the total mass of the stripping reagent; the alkali is at least one of potassium hydroxide, sodium hydroxide, lithium hydroxide, ammonia water, sodium bicarbonate and sodium carbonate;
the organic solvent is at least one selected from acetone, cyclohexanone, cyclohexane, benzene, toluene, xylene, propanol, ethyl acetate, N-methyl-2-pyrrolidone and dimethyl sulfoxide.
2. The stripping agent according to claim 1, wherein the organic solvent is benzene and benzyl alcohol in a mass ratio of (2-5): 1.
3. The stripping agent according to claim 1, wherein the organic solvent is benzene and acetone in a mass ratio of (6-8): 1.
4. The stripping agent according to claim 1, wherein the organic solvent is toluene and dimethyl sulfoxide at a mass ratio of (4-7): 1.
5. The stripping agent according to claim 1, wherein the base accounts for 0.0001% to 5% of the total mass of the stripping agent.
6. The stripping reagent as claimed in claim 1, wherein the stripping reagent further comprises water, and the water accounts for 0.0006% -20% of the total mass of the stripping reagent.
7. The stripping agent as claimed in claim 1, wherein the concentration of the alkali solution is 0.1 wt.% to 18 wt.%.
8. A method for stripping a coating of a secondary battery separator, comprising:
placing the secondary battery separator carrying the coating layer in the stripping agent according to any one of claims 1 to 7 to separate the separator and the coating layer.
9. The method for stripping coating of secondary battery separator according to claim 8, wherein the step of separating the separator and the coating comprises: separating the membrane from the coating layer by ultrasonic treatment at 20-80 ℃ for 0.5-4 h.
10. The peeling method of a secondary battery separator coating layer according to claim 8, wherein a material of the separator is selected from at least one of polyethylene, polypropylene, polybutylene, polypentylene, and polyethylene terephthalate; the material of the coating comprises a polymer or a ceramic.
11. The method for stripping a coating of a secondary battery separator according to claim 8, wherein the material of the coating comprises at least one of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene-alumina ceramic, and polymethyl methacrylate and derivatives thereof; alternatively, the material of the coating comprises at least one of alumina, boehmite, attapulgite, silica, titania, magnesia, zirconia, and silicon carbide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110569671.XA CN113293000B (en) | 2021-05-21 | 2021-05-21 | Stripping reagent and stripping method of secondary battery diaphragm coating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110569671.XA CN113293000B (en) | 2021-05-21 | 2021-05-21 | Stripping reagent and stripping method of secondary battery diaphragm coating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113293000A CN113293000A (en) | 2021-08-24 |
| CN113293000B true CN113293000B (en) | 2022-06-17 |
Family
ID=77324625
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110569671.XA Active CN113293000B (en) | 2021-05-21 | 2021-05-21 | Stripping reagent and stripping method of secondary battery diaphragm coating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113293000B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105388713A (en) * | 2015-12-16 | 2016-03-09 | 无锡吉进环保科技有限公司 | Aluminum film drainage photoresist stripper in thin-film liquid crystal display |
| CN108242522A (en) * | 2016-12-23 | 2018-07-03 | 比亚迪股份有限公司 | A kind of composite membrane of polymer and preparation method thereof and the lithium ion battery for including it |
| CN108417760A (en) * | 2018-02-10 | 2018-08-17 | 郑州大学 | A kind of sodium/sodium-ion battery nonwoven cloth diaphragm and preparation method thereof |
| CN109659475A (en) * | 2018-11-26 | 2019-04-19 | 华南师范大学 | A kind of preparation method of high-performance high-voltage lithium ion battery |
| CN112635917A (en) * | 2020-12-29 | 2021-04-09 | 浙江大学 | High-strength functional diaphragm for alkali metal-based battery, preparation method of high-strength functional diaphragm and alkali metal-based battery |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108370011B (en) * | 2015-10-08 | 2021-11-02 | 艾沃伦24公司 | Chargeable aluminium ion battery |
-
2021
- 2021-05-21 CN CN202110569671.XA patent/CN113293000B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105388713A (en) * | 2015-12-16 | 2016-03-09 | 无锡吉进环保科技有限公司 | Aluminum film drainage photoresist stripper in thin-film liquid crystal display |
| CN108242522A (en) * | 2016-12-23 | 2018-07-03 | 比亚迪股份有限公司 | A kind of composite membrane of polymer and preparation method thereof and the lithium ion battery for including it |
| CN108417760A (en) * | 2018-02-10 | 2018-08-17 | 郑州大学 | A kind of sodium/sodium-ion battery nonwoven cloth diaphragm and preparation method thereof |
| CN109659475A (en) * | 2018-11-26 | 2019-04-19 | 华南师范大学 | A kind of preparation method of high-performance high-voltage lithium ion battery |
| CN112635917A (en) * | 2020-12-29 | 2021-04-09 | 浙江大学 | High-strength functional diaphragm for alkali metal-based battery, preparation method of high-strength functional diaphragm and alkali metal-based battery |
Non-Patent Citations (1)
| Title |
|---|
| 锂电隔膜陶瓷涂层浆料稳定性研究;张文静等;《信息记录材料》;20200430;第21卷(第4期);7-10 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113293000A (en) | 2021-08-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6031179B2 (en) | Power storage device separator, laminate, and porous film | |
| EP3179536B1 (en) | Porous film and multilayer porous film | |
| JP4931083B2 (en) | Multilayer porous membrane and method for producing the same | |
| JP5495210B2 (en) | Composite porous membrane, method for producing composite porous membrane, and battery separator using the same | |
| CN107256939B (en) | Laminated porous film and nonaqueous electrolyte secondary battery | |
| TWI714744B (en) | Separator for secondary battery and secondary battery | |
| TWI336718B (en) | ||
| JP5448345B2 (en) | Multilayer porous membrane and method for producing the same | |
| JP6345660B2 (en) | Nonaqueous electrolyte battery separator and nonaqueous electrolyte battery | |
| EP1685955A1 (en) | Composite microporous film, and production method and use thereof | |
| JP2016510267A (en) | Composite microporous membrane with excellent electrochemical stability and method for producing the same | |
| JPH11213982A (en) | Battery separator and battery | |
| JP6412760B2 (en) | Storage device separator | |
| JP2016072247A (en) | Separator for power storage device | |
| JP6378998B2 (en) | Method for manufacturing separator for power storage device | |
| CN113293000B (en) | Stripping reagent and stripping method of secondary battery diaphragm coating | |
| JP6357395B2 (en) | Battery separator | |
| JP5295857B2 (en) | Nonaqueous electrolyte battery separator and nonaqueous electrolyte battery | |
| JPWO2017187780A1 (en) | Slurry for secondary battery separator, separator for secondary battery and method for producing them | |
| KR20020076246A (en) | Microporous membrane | |
| TWI511352B (en) | Ion polymer film material and its preparation method and lithium secondary battery | |
| KR102425089B1 (en) | Manuafcturing method of bohemite for lithium secondary battery separator coating agent | |
| JP2008106261A (en) | Porous membrane containing aromatic polyamide | |
| CN113540692A (en) | Environment-friendly oily PVDF (polyvinylidene fluoride) coated diaphragm and preparation method thereof | |
| JPH0338227A (en) | Preparation of porous polymer membrane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |