CN114335700A - Solid electrolyte membrane and preparation method thereof, secondary battery and preparation method - Google Patents
Solid electrolyte membrane and preparation method thereof, secondary battery and preparation method Download PDFInfo
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Abstract
The invention belongs to the technical field of secondary batteries, and particularly relates to a solid electrolyte membrane and a preparation method thereof, a secondary battery and a preparation method thereof. The solid electrolyte membrane has certain mechanical strength and toughness, can prevent dendritic crystal from growing and penetrating, and the ceramic electrolyte base membrane of the middle layer has excellent ionic conductivity; the upper surface and the lower surface of the middle layer are coated with coating layers, so that the solid electrolyte membrane has a wider electrochemical window and better stability and can resist high voltage; the fluorine-containing coating layer attached to the positive plate has good wettability with the positive plate, is more uniform and compact in attachment, and simultaneously enhances the mechanical strength and toughness; the fluorine-containing coating layer attached to the negative plate can help the negative surface to form an SEI layer with high fluorine content, can inhibit dendritic crystals to a certain degree and also can have a better interface, and meanwhile, the mechanical strength and the toughness are enhanced.
Description
Technical Field
The invention belongs to the technical field of secondary batteries, and particularly relates to a solid electrolyte membrane and a preparation method thereof, a secondary battery and a preparation method thereof.
Background
The huge market for electric vehicles and portable electronic devices is driving the rapid development of energy storage systems with high energy density and high safety. Lithium metal anodes are considered to be a preferred solution for high energy density battery anodes due to their extremely high theoretical capacity and low redox potential. However, lithium metal batteries face severe lithium dendrite growth problems, the potential short circuit risk and flammable liquid electrolytes leave considerable safety hazards.
It is known that the replacement of the liquid electrolyte in a lithium metal battery with a solid electrolyte is effective in improving its safety problem because the solid electrolyte is generally non-flammable and its mechanical strength can block the penetration of dendrites to the positive electrode. However, currently, no single solid-state electrolyte is compatible with both a high-reducibility and high-chemical-activity lithium metal negative electrode and a high-oxidative high-voltage positive electrode. Meanwhile, the interfacial contact of the solid electrolyte and the positive and negative electrode materials is also a great challenge faced by the solid electrolyte, especially in the lithium metal battery, the contact of the positive electrode side and the solid electrolyte greatly affects the transmission of lithium ions at the interface and the overall polarization level of the battery, and the contact of the negative electrode side and the solid electrolyte affects the lithium deposition and dissolution processes.
On the other hand, after the solid electrolyte is adopted, because the inside of the positive electrode loses the infiltration of the liquid electrolyte and is lack of a proper ion channel, the conduction of lithium ions is very difficult, the polarization of the positive electrode side is very large, the battery capacity and the voltage platform can not be normally exerted, and the huge loss of the energy density of the battery core is caused.
Disclosure of Invention
One of the objects of the present invention is: aiming at the defects of the prior art, the solid electrolyte membrane is tightly contacted with the pole pieces, can form stable SEI films on the surfaces of the positive pole piece and the negative pole piece, has good wettability to the positive pole piece and the negative pole piece, and has strong mechanical strength and toughness.
In order to achieve the purpose, the invention adopts the following technical scheme:
a solid electrolyte membrane includes a ceramic electrolyte base membrane and fluorine-containing coating layers coated on both side surfaces of the ceramic electrolyte base membrane.
The solid electrolyte membrane is composed of three layers of composite membranes, has certain mechanical strength and toughness, can prevent dendritic crystal from growing and penetrating to a certain extent, and the ceramic electrolyte base membrane of the middle layer has excellent ionic conductivity and is easy to react with air to form an inert ion-conducting layer, so that coating layers are coated on the upper surface and the lower surface of the middle layer, so that the solid electrolyte membrane has a wider electrochemical window and better stability and can withstand high voltage; the fluorine-containing coating layer attached to the positive plate has good wettability with the positive plate, is more uniform and compact in attachment, and simultaneously enhances the mechanical strength and toughness; the fluorine-containing coating layer attached to the negative plate can help the negative surface to form an SEI layer with high fluorine content, can inhibit dendritic crystals to a certain degree and also can have a better interface, and meanwhile, the mechanical strength and the toughness are enhanced.
Preferably, the thickness of the fluorine-containing coating layer is 1 to 10 μm, and the thickness of the ceramic electrolyte base film is 3 to 30 μm. The upper surface and the lower surface of the ceramic electrolyte base film are coated with the coating layer, so that the fluorine-containing coating layer completely coats the ceramic electrolyte base film, possible micro pores in the ceramic electrolyte base film can be blocked, and the condition that the gel electrolyte precursor mixed solution possibly causes partial dissolution to the ceramic electrolyte base film is avoided. The certain thickness is set to maintain certain performance and provide certain mechanical strength.
Preferably, the fluorine-containing coating layer comprises a first fluorine-containing coating layer comprising a first fluorine-containing polymer and a second fluorine-containing coating layer comprising a second fluorine-containing polymer having a fluorine content greater than that of the first fluorine-containing polymer. The second fluorine-containing coating uses the second fluorine-containing polymer with higher fluorine content, so that the negative electrode forms an SEI layer with high fluorine content, dendritic crystals can be inhibited to a certain degree, a better interface can be provided, and the mechanical strength and toughness are enhanced simultaneously, so that the solid electrolyte membrane can have a positive electrode and a negative electrode simultaneously.
Preferably, the first fluorine-containing coating further comprises a lithium salt and an ionic liquid, and the weight part ratio of the lithium salt to the ionic liquid to the first fluorine-containing polymer in the first fluorine-containing coating is 2-10: 2-8: 10-15; the second fluorine-containing coating further comprises lithium salt and ionic liquid, and the weight part ratio of the lithium salt to the ionic liquid to the second fluorine-containing polymer in the second fluorine-containing coating is 2-10: 2-8: 10-15. Lithium salt and ionic liquid are added into the first fluorine-containing coating and the second fluorine-containing coating, lithium ions can be provided for the solid electrolyte membrane, and the ionic conductivity of the solid electrolyte membrane is improved.
Preferably, the ceramic electrolyte base film comprises a lithium salt, an ionic liquid, an intermediate polymer and ion-conducting ceramic powder, wherein the weight part ratio of the lithium salt to the ionic liquid to the intermediate polymer to the ion-conducting ceramic powder is 0.5-5: 2-8: 5-10. The lithium salt can provide lithium ions, the ionic liquid can improve the ionic conductivity of the solid electrolyte membrane, and the ion-conducting ceramic powder can improve the ionic conductivity of the polymer solid electrolyte and enhance the mechanical strength of the membrane.
Preferably, the first fluoropolymer and/or the second fluoropolymer comprises at least one of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, vinylidene fluoride-trifluoroethylene.
Preferably, the lithium salt includes at least one of lithium hexafluorophosphate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (fluorosulfonyl) imide, lithium difluorooxalato borate, lithium perchlorate, lithium bisoxalato borate, lithium tetrafluorooxalato phosphate, and lithium difluorooxalato phosphate.
Preferably, the ion-conducting ceramic powder comprises one or more of lithium aluminum titanium phosphate, lithium lanthanum zirconium oxide, lithium lanthanum titanium oxide, lithium phosphorus oxynitride and doped oxides thereof.
Wherein the ionic liquid comprises one of imidazole ionic liquid or pyrrole ionic liquid. The intermediate polymer comprises one of polyethylene oxide, polyacrylonitrile and polymethyl methacrylate. The first fluorine-containing coating, the ceramic electrolyte base film and the second fluorine-containing coating all comprise solvents, the solvents are volatile solvents, and the volatile solvents comprise one of N, N-dimethylformamide, N-dimethylacetamide, anhydrous acetonitrile and N-methylpyrrolidone.
The second purpose of the invention is: aiming at the defects of the prior art, the preparation method of the solid electrolyte membrane is provided, is simple to operate and can be used for mass production.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for producing a solid electrolyte membrane, comprising the steps of:
step S1: selecting a lithium salt, an ionic liquid, a first fluorine-containing polymer and a solvent, mixing the lithium salt, the ionic liquid, the first fluorine-containing polymer and the solvent to obtain a first mixed solution, coating the first mixed solution on a bearing substrate, and drying to obtain a fluorine-containing coating layer;
step S2, selecting lithium salt, ionic liquid, intermediate polymer, solvent and ion-conducting ceramic powder, mixing the lithium salt, the ionic liquid, the intermediate polymer and the solvent to obtain a pretreatment solution, adding the ion-conducting ceramic powder into the pretreatment solution, stirring and dispersing to obtain a second mixed solution, coating the second mixed solution on the surface of the fluorine-containing coating layer, and drying to form a ceramic electrolyte base membrane;
and step S3, selecting a lithium salt, an ionic liquid, a second fluoropolymer and a solvent, mixing the lithium salt, the ionic liquid, the second fluoropolymer and the solvent to obtain a third mixed solution, coating the third mixed solution on the surface of the ceramic electrolyte base film, and drying to form a fluorine-containing coating layer, thereby obtaining the solid electrolyte film.
The third purpose of the invention is that: in view of the deficiencies of the prior art, a secondary battery is provided, which has good mechanical strength, wettability and ionic conductivity and can meet the requirements of stability of positive and negative electrodes.
In order to achieve the purpose, the invention adopts the following technical scheme:
a secondary battery comprising the above solid electrolyte membrane.
Wherein, justThe pole piece comprises a positive pole current collector and an active substance layer coated on the surface of the positive pole current collector, wherein the active substance layer comprises a positive pole active substance, and the positive pole active substance comprises but is not limited to a chemical formula such as LiaNixCoyMzO2-bNb(wherein a is more than or equal to 0.95 and less than or equal to 1.2, x>0, y is not less than 0, z is not less than 0, and x + y + z is 1,0 is not less than b is not more than 1, M is selected from one or more of Mn and Al, N is selected from one or more of F, P and S), and the positive electrode active material can also be a combination including but not limited to LiCoO)2、LiNiO2、LiVO2、LiCrO2、LiMn2O4、LiCoMnO4、Li2NiMn3O8、LiNi0.5Mn1.5O4、LiCoPO4、LiMnPO4、LiFePO4、LiNiPO4、LiCoFSO4、CuS2、FeS2、MoS2、NiS、TiS2And the like. The positive electrode active material may be further modified, and the method of modifying the positive electrode active material is known to those skilled in the art, for example, the positive electrode active material may be modified by coating, doping, and the like, and the material used in the modification may be one or a combination of more of Al, B, P, Zr, Si, Ti, Ge, Sn, Mg, Ce, W, and the like. And the positive electrode current collector is generally a structure or a part for collecting current, and the positive electrode current collector may be any material suitable for being used as a positive electrode current collector of a lithium ion battery in the field, for example, the positive electrode current collector may include, but is not limited to, a metal foil and the like, and more specifically, may include, but is not limited to, an aluminum foil and the like.
The fourth purpose of the invention is that: aiming at the defects of the prior art, the preparation method of the secondary battery is provided, has simple steps and can be produced in batch.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for manufacturing a secondary battery, comprising the steps of:
a1, selecting lithium salt, organic solvent, additive and initiator, and mixing the lithium salt, the organic solvent, the additive and the initiator to obtain a precursor mixed solution of the gel electrolyte;
step A2, selecting a positive plate, a lithium metal negative plate and a shell, preparing the positive plate, a solid electrolyte membrane and the lithium metal negative plate into a bare cell, and installing the bare cell in the shell for packaging;
and step A3, injecting the gel electrolyte precursor mixed solution into a shell for packaging, standing, heating for reaction, forming, hot-cold pressing, degassing and vacuum packaging to obtain the secondary battery.
Before assembly and packaging, baking the positive plate and the solid electrolyte membrane at the baking temperature of 40-120 ℃ for 6-24 hours, wherein the working procedures before formation are all carried out in a drying room with the dew point of less than-35 ℃. The baking can avoid the influence of moisture on the battery cell and the lithium metal negative electrode. After baking, assembling the positive plate, the solid electrolyte membrane and the metal lithium negative plate into a bare cell, packaging, injecting gel electrolyte precursor mixed solution, heating to enable the gel electrolyte precursor mixed solution to be heated to generate in-situ polymerization, enabling the gel electrolyte to be completely consumed, and enabling no liquid component in the cell to be present, thereby preparing the solid secondary battery. Wherein the heating temperature is 60-85 ℃, and the heating time is 1-5 hours. Wherein the shell is made of one of aluminum plastic film and stainless steel sheet. Preferably, the material of the shell is an aluminum plastic film.
Lithium salt in the precursor mixed liquor of the gel electrolyte comprises at least one of lithium hexafluorophosphate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (fluorosulfonyl) imide, lithium difluorooxalato borate, lithium perchlorate, lithium bisoxalato borate, lithium tetrafluorooxalato phosphate, lithium difluorooxalato phosphate and the like, and accounts for 5-15% of the mass of the precursor mixed liquor of the gel electrolyte; the organic solvent in the gel electrolyte precursor mixed solution comprises at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, propyl propionate, fluoroethylene carbonate, methyl trifluoroethyl carbonate, 1,2, 2-tetrafluoroethyl 2,2, 2-trifluoroethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether; the organic solvent accounts for 80-95% of the mass of the gel electrolyte precursor mixed solution. The additive in the precursor mixed solution of the gel electrolyte is a monomer containing an unsaturated bond, and comprises at least one of polyethylene glycol diacrylate, methyl methacrylate, pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, vinyl acetate and vinyl sulfite; the additive accounts for 2-10% of the mass percent of the gel electrolyte precursor mixed solution; the initiator in the gel electrolyte precursor mixed solution comprises at least one of azobisisobutyronitrile, azobisisoheptonitrile, dimethyl azobisisobutyrate and dibenzoyl peroxide; the initiator accounts for 0.1-2% of the mass of the gel electrolyte precursor mixed solution. The positive active material comprises at least one of lithium cobaltate, lithium nickel cobalt manganese oxide, lithium iron phosphate, lithium manganese oxide, a nickel manganese binary material and lithium nickel cobalt aluminate. And the anode active material powder particles are all coated by oxide solid electrolyte, the oxide solid electrolyte for coating comprises one of titanium aluminum lithium phosphate, lithium lanthanum zirconium oxygen, lithium lanthanum titanium oxygen, lithium phosphorus oxygen nitrogen and doped oxide solid electrolyte material, and the coating amount is 2-20 wt%.
According to the preparation method of the solid lithium metal battery, the interior of the anode is infiltrated by adopting a trace amount of gel electrolyte precursor mixed solution, then the mixed solution is subjected to in-situ polymerization reaction under a high temperature condition to form a polymer solid electrolyte, and the anode material particles are wrapped by the oxide solid electrolyte, so that the ion conduction in the anode is greatly improved under the condition of double tubes, and meanwhile, the contact interface between the asymmetric solid electrolyte membrane and the anode and the cathode is also improved, so that the performance of the solid lithium metal battery is improved.
The metal lithium piece is as the negative pole piece, assembles into naked electric core with positive plate, solid electrolyte membrane, and when assembling, first fluorine-containing coating in the solid electrolyte membrane and the laminating of positive plate, the laminating of second fluorine-containing coating in the solid electrolyte membrane and metal lithium negative pole piece assemble into naked electric core, pour into gel electrolyte precursor mixed liquid.
Preferably, the weight part ratio of the lithium salt, the organic solvent, the additive and the initiator in the step A1 is 5-15: 80-95: 2-20: 0.1-2.
Compared with the prior art, the invention has the beneficial effects that: the solid electrolyte membrane is composed of three layers of composite membranes, has certain mechanical strength and toughness, can prevent dendritic crystal from growing and penetrating to a certain extent, and the ceramic electrolyte base membrane of the middle layer has excellent ionic conductivity and is easy to react with air to form an inert ion-conducting layer, so that coating layers are coated on the upper surface and the lower surface of the middle layer, so that the solid electrolyte membrane has a wider electrochemical window and better stability and can withstand high voltage; the fluorine-containing coating layer attached to the positive plate has good wettability with the positive plate, is more uniform and compact in attachment, and simultaneously enhances the mechanical strength and toughness; the fluorine-containing coating layer attached to the negative plate can help the negative surface to form an SEI layer with high fluorine content, can inhibit dendritic crystals to a certain degree and also can have a better interface, and meanwhile, the mechanical strength and the toughness are enhanced.
Detailed Description
The present invention will be described in further detail with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.
Example 1
1. A method for producing a solid electrolyte membrane, comprising the steps of:
the method comprises the following steps: adding a mixture of lithium bis (trifluoromethylsulfonyl) imide and a small amount of ionic liquid 1-ethyl-3-methylimidazole bis (trifluoromethylsulfonyl) imide salt (EMI-TFSI) into a mixed solution consisting of polytetrafluoroethylene and N, N-dimethylformamide, stirring to form a uniform and transparent solution, then uniformly coating the solution on a glass plate by a slurry coating method, and drying at 60 ℃ for later use, wherein the weight part ratio of the lithium salt, the ionic liquid and the polytetrafluoroethylene in the solution is 3.5:3:13.8, this is a first fluorine containing coating;
step two: adding a mixture of lithium bis (trifluoromethylsulfonyl) imide and a small amount of ionic liquid 1-ethyl-3-methylimidazole bis (trifluoromethylsulfonyl) imide salt (EMI-TFSI) into a mixed solution consisting of polyethylene oxide and anhydrous acetonitrile, stirring to form a uniform and transparent solution, then adding lithium lanthanum zirconium tantalum oxygen powder into the solution, stirring and uniformly dispersing, finally uniformly coating the dispersion on a first fluorine-containing coating by adopting a slurry coating method, and drying at 45 ℃ to form a ceramic electrolyte base membrane, wherein the weight part ratio of the lithium salt, the ionic liquid, the polyethylene oxide and the lithium lanthanum zirconium tantalum oxygen powder in the solution is 0.82: 3: 3.3: 6.5;
step three: and (2) adding a mixture of lithium bis (trifluoromethylsulfonyl) imide and a small amount of ionic liquid 1-ethyl-3-methylimidazole bis (trifluoromethylsulfonyl) imide salt (EMI-TFSI) into a mixed solution consisting of polyvinylidene fluoride-hexafluoropropylene and N, N-dimethylformamide, stirring to form a uniform and transparent solution, then uniformly coating the solution on the ceramic electrolyte base membrane in the second step by a slurry coating method, and drying at 50 ℃ to form a second fluorine-containing coating to obtain the solid electrolyte membrane. In the step, the mass fractions of the lithium salt, the ionic liquid and the polytetrafluoroethylene in the solution are respectively 3.5:3:13.8 obtaining a second fluorine containing coating.
2. One solid electrolyte membrane is Polytetrafluoroethylene (PVDF) | polyethylene oxide (PEO) -Lithium Lanthanum Zirconium Tantalum Oxygen (LLZTO) | polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) asymmetric solid electrolyte membrane, the membrane thickness is 36 μm. The first fluorine-containing coating is a polytetrafluoroethylene film and consists of polytetrafluoroethylene, lithium bis (trifluoromethylsulfonyl) imide (LiTFSI) and a small amount of Ionic Liquid (IL). The middle ceramic electrolyte basement membrane is a polyoxyethylene-lithium lanthanum zirconium tantalum oxygen membrane, and consists of polyoxyethylene, lithium lanthanum zirconium tantalum oxygen powder, lithium bis (trifluoromethylsulfonyl) imide and a small amount of ionic liquid. The second fluorine-containing coating is a polyvinylidene fluoride-hexafluoropropylene film and consists of polyvinylidene fluoride-hexafluoropropylene, lithium bis (trifluoromethylsulfonyl) imide and a small amount of ionic liquid.
3. A method for manufacturing a secondary battery, comprising the steps of:
a1, selecting lithium salt, organic solvent, additive and initiator, and mixing the lithium salt, the organic solvent, the additive and the initiator to obtain a precursor mixed solution of the gel electrolyte;
step A2, selecting an aluminum foil as a positive plate, a lithium metal negative plate and an aluminum plastic film shell, preparing the positive plate, a solid electrolyte film and the lithium metal negative plate into a bare cell, and installing the bare cell in the shell for packaging;
and step A3, injecting the gel electrolyte precursor mixed solution into a shell for packaging, standing, heating for reaction, forming, hot-cold pressing, degassing and vacuum packaging to obtain the secondary battery.
The lithium salt is a mixed lithium salt of lithium bis (trifluoromethylsulfonyl) imide, lithium difluorooxalate borate and lithium hexafluorophosphate, and the three lithium salts respectively account for 16 wt%, 2 wt% and 0.5 wt% of the precursor mixed solution of the gel electrolyte. The organic solvent is methyl ethyl carbonate and dimethyl carbonate, which respectively account for 36 wt% and 38.5 wt% of the precursor mixed solution of the gel electrolyte. The additive is pentaerythritol triacrylate and ethoxylated trimethylolpropane triacrylate, which respectively account for 4.6 wt% and 2.3 wt% of the precursor mixed solution of the gel electrolyte. The initiator is azobisisobutyronitrile, and accounts for 0.1 wt% of the precursor mixed solution of the gel electrolyte.
4. A secondary battery is prepared by the method.
Example 2
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid and the first fluorine-containing polymer in the first fluorine-containing coating is 2:2: 10; the weight part ratio of the lithium salt, the ionic liquid and the second fluorine-containing polymer in the second fluorine-containing coating is 2:2: 10.
The rest is the same as embodiment 1, and the description is omitted here.
Example 3
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid and the first fluorine-containing polymer in the first fluorine-containing coating is 2:4: 12; the weight part ratio of the lithium salt, the ionic liquid and the second fluorine-containing polymer in the second fluorine-containing coating is 2:4: 12.
The rest is the same as embodiment 1, and the description is omitted here.
Example 4
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid and the first fluorine-containing polymer in the first fluorine-containing coating is 2:8: 15; the weight part ratio of the lithium salt, the ionic liquid and the second fluorine-containing polymer in the second fluorine-containing coating is 2:8: 15.
The rest is the same as embodiment 1, and the description is omitted here.
Example 5
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid and the first fluorine-containing polymer in the first fluorine-containing coating is 5:2: 10; the weight part ratio of the lithium salt, the ionic liquid and the second fluorine-containing polymer in the second fluorine-containing coating is 5:2: 10.
The rest is the same as embodiment 1, and the description is omitted here.
Example 6
The difference from example 1 is that: the weight part ratio of the lithium salt to the ionic liquid to the first fluorine-containing polymer in the first fluorine-containing coating is 5:5: 13; the weight part ratio of the lithium salt, the ionic liquid and the second fluorine-containing polymer in the second fluorine-containing coating is 5:5: 13.
The rest is the same as embodiment 1, and the description is omitted here.
Example 7
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid, the intermediate polymer and the ion conducting ceramic powder is 2.5:6:5: 8.
The rest is the same as embodiment 1, and the description is omitted here.
Example 8
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid, the intermediate polymer and the ion conducting ceramic powder is 4:5:6: 8.
The rest is the same as embodiment 1, and the description is omitted here.
Example 9
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid, the intermediate polymer and the ion conducting ceramic powder is 1.5:6:5: 10.
The rest is the same as embodiment 1, and the description is omitted here.
Example 10
The difference from example 1 is that: the weight part ratio of the lithium salt, the ionic liquid, the intermediate polymer and the ion conducting ceramic powder is 4:6:5: 8.
The rest is the same as embodiment 1, and the description is omitted here.
Comparative example 1:
the difference from example 1 is that: the preparation method of the solid electrolyte membrane comprises the following steps of dissolving lithium salt, ionic liquid, polyethylene oxide (PEO) and Lithium Lanthanum Zirconium Oxide (LLZO) in a solution according to the weight part ratio of 0.82: 1: 3.3: 6.5 mixing to obtain the solid electrolyte membrane.
The rest is the same as embodiment 1, and the description is omitted here.
And (3) performance testing: the secondary batteries prepared in the above examples 1 to 10 and comparative example 1 were subjected to a performance test, and the test results are reported in table 1.
TABLE 1
As can be seen from table 1, the secondary battery obtained by the preparation method of the present invention has better first cycle efficiency, gram capacity, and cycle life than the solid electrolyte membrane of reference 1, which indicates that the solid electrolyte membrane of the present invention has good stability, and is compatible with the positive electrode sheet and the negative electrode sheet, and avoids dendrites. From the comparison of examples 1-6, when the weight part ratio of the lithium salt, the ionic liquid and the first fluoropolymer in the first fluorine-containing coating layer is set to 3.5:3: 13.8; when the weight part ratio of the lithium salt, the ionic liquid and the second fluorine-containing polymer in the second fluorine-containing coating is 3.5:3:13.8, the prepared secondary battery has better performance. From the comparison of examples 1 and 7-10, when the weight part ratio of the lithium salt, the ionic liquid, the polyethylene oxide and the lithium lanthanum zirconium tantalum oxygen powder in the solution is set to be 0.82: 3: 3.3: and 6.5, the prepared secondary battery has better performance.
Variations and modifications to the above-described embodiments may also occur to those skilled in the art, which fall within the scope of the invention as disclosed and taught herein. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious improvement, replacement or modification made by those skilled in the art based on the present invention is within the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims (12)
1. The solid electrolyte membrane is characterized by comprising a ceramic electrolyte base membrane and fluorine-containing coating layers coated on the two side surfaces of the ceramic electrolyte base membrane.
2. The solid electrolyte membrane according to claim 1, wherein the fluorine-containing coating layer has a thickness of 1 to 10 μm, and the ceramic electrolyte-based membrane has a thickness of 3 to 30 μm.
3. The solid electrolyte membrane according to claim 1, wherein the fluorine-containing coating layer comprises a first fluorine-containing coating layer comprising a first fluorine-containing polymer and a second fluorine-containing coating layer comprising a second fluorine-containing polymer having a fluorine content greater than that of the first fluorine-containing polymer.
4. The solid electrolyte membrane according to claim 3, wherein the first fluorine-containing coating further comprises a lithium salt and an ionic liquid, and the weight ratio of the lithium salt to the ionic liquid to the first fluorine-containing polymer in the first fluorine-containing coating is 2-10: 2-8: 10-15; the second fluorine-containing coating further comprises lithium salt and ionic liquid, and the weight part ratio of the lithium salt to the ionic liquid to the second fluorine-containing polymer in the second fluorine-containing coating is 2-10: 2-8: 10-15.
5. The solid electrolyte membrane according to claim 4, wherein the first fluoropolymer and/or the second fluoropolymer comprises at least one of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, vinylidene fluoride-trifluoroethylene.
6. The solid electrolyte membrane according to claim 1, wherein the ceramic electrolyte base membrane comprises a lithium salt, an ionic liquid, an intermediate polymer and an ion-conducting ceramic powder, and the weight ratio of the lithium salt, the ionic liquid, the intermediate polymer and the ion-conducting ceramic powder is 0.5-5: 2-8: 5-10.
7. The solid electrolyte membrane according to claim 4 or 6, wherein the lithium salt comprises at least one of lithium hexafluorophosphate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (fluorosulfonyl) imide, lithium difluorooxalato borate, lithium perchlorate, lithium bis-oxalato borate, lithium tetrafluorooxalato phosphate, and lithium difluorooxalato phosphate.
8. The solid electrolyte membrane according to claim 6, wherein the ion conducting ceramic powder comprises one or more of lithium aluminum titanium phosphate, lithium lanthanum zirconium oxygen, lithium lanthanum titanium oxygen, and lithium phosphorus oxynitride and doped oxides thereof.
9. The method for producing a solid electrolyte membrane according to any one of claims 1 to 8, characterized by comprising the steps of:
step S1: selecting a lithium salt, an ionic liquid, a first fluorine-containing polymer and a solvent, mixing the lithium salt, the ionic liquid, the first fluorine-containing polymer and the solvent to obtain a first mixed solution, coating the first mixed solution on a bearing substrate, and drying to obtain a fluorine-containing coating layer;
step S2, selecting lithium salt, ionic liquid, intermediate polymer, solvent and ion-conducting ceramic powder, mixing the lithium salt, the ionic liquid, the intermediate polymer and the solvent to obtain a pretreatment solution, adding the ion-conducting ceramic powder into the pretreatment solution, stirring and dispersing to obtain a second mixed solution, coating the second mixed solution on the surface of the fluorine-containing coating layer, and drying to form a ceramic electrolyte base membrane;
and step S3, selecting a lithium salt, an ionic liquid, a second fluoropolymer and a solvent, mixing the lithium salt, the ionic liquid, the second fluoropolymer and the solvent to obtain a third mixed solution, coating the third mixed solution on the surface of the ceramic electrolyte base film, and drying to form a fluorine-containing coating layer, thereby obtaining the solid electrolyte film.
10. A secondary battery characterized by comprising the solid electrolyte membrane according to any one of claims 1 to 8.
11. The method for manufacturing a secondary battery according to claim 10, characterized by comprising the steps of:
a1, selecting lithium salt, organic solvent, additive and initiator, and mixing the lithium salt, the organic solvent, the additive and the initiator to obtain a precursor mixed solution of the gel electrolyte;
step A2, selecting a positive plate, a lithium metal negative plate and a shell, preparing the positive plate, a solid electrolyte membrane and the lithium metal negative plate into a bare cell, and installing the bare cell in the shell for packaging;
and step A3, injecting the gel electrolyte precursor mixed solution into a shell for packaging, standing, heating for reaction, forming, hot-cold pressing, degassing and vacuum packaging to obtain the secondary battery.
12. The method for preparing the secondary battery according to claim 11, wherein the weight ratio of the lithium salt, the organic solvent, the additive and the initiator in the step A1 is 5-15: 80-95: 2-20: 0.1-2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210036566.4A CN114335700A (en) | 2022-01-13 | 2022-01-13 | Solid electrolyte membrane and preparation method thereof, secondary battery and preparation method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115425286A (en) * | 2022-11-04 | 2022-12-02 | 中国科学院宁波材料技术与工程研究所 | Film based on nano sulfide solid electrolyte, preparation method and application |
| CN115632159A (en) * | 2022-12-22 | 2023-01-20 | 佛山(华南)新材料研究院 | Preparation method of multilayer lithium lanthanum zirconium oxide ceramic electrolyte sheet |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016127786A1 (en) * | 2015-02-13 | 2016-08-18 | 中国科学院青岛生物能源与过程研究所 | All-solid-state polymer electrolyte, and preparation and application thereof |
| CN111244537A (en) * | 2020-02-24 | 2020-06-05 | 南方科技大学 | Composite solid electrolyte, solid battery and preparation method thereof |
| CN111697262A (en) * | 2019-03-14 | 2020-09-22 | 深圳格林德能源集团有限公司 | Composite solid electrolyte, all-solid-state lithium ion battery and preparation method thereof |
| CN113054241A (en) * | 2021-03-04 | 2021-06-29 | 湖南立方新能源科技有限责任公司 | Solid-state lithium battery and preparation method thereof |
| CN113707936A (en) * | 2021-08-27 | 2021-11-26 | 河南省法恩莱特新能源科技有限公司 | Gel polymer electrolyte for soft package lithium battery and preparation method thereof |
-
2022
- 2022-01-13 CN CN202210036566.4A patent/CN114335700A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016127786A1 (en) * | 2015-02-13 | 2016-08-18 | 中国科学院青岛生物能源与过程研究所 | All-solid-state polymer electrolyte, and preparation and application thereof |
| CN111697262A (en) * | 2019-03-14 | 2020-09-22 | 深圳格林德能源集团有限公司 | Composite solid electrolyte, all-solid-state lithium ion battery and preparation method thereof |
| CN111244537A (en) * | 2020-02-24 | 2020-06-05 | 南方科技大学 | Composite solid electrolyte, solid battery and preparation method thereof |
| CN113054241A (en) * | 2021-03-04 | 2021-06-29 | 湖南立方新能源科技有限责任公司 | Solid-state lithium battery and preparation method thereof |
| CN113707936A (en) * | 2021-08-27 | 2021-11-26 | 河南省法恩莱特新能源科技有限公司 | Gel polymer electrolyte for soft package lithium battery and preparation method thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115425286A (en) * | 2022-11-04 | 2022-12-02 | 中国科学院宁波材料技术与工程研究所 | Film based on nano sulfide solid electrolyte, preparation method and application |
| CN115632159A (en) * | 2022-12-22 | 2023-01-20 | 佛山(华南)新材料研究院 | Preparation method of multilayer lithium lanthanum zirconium oxide ceramic electrolyte sheet |
| CN115632159B (en) * | 2022-12-22 | 2023-02-28 | 佛山(华南)新材料研究院 | Preparation method of multilayer lithium lanthanum zirconium oxide ceramic electrolyte sheet |
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