KR101624642B1 - Electrolyte ink and solid electrolyte membrane formed by using same - Google Patents

Abstract

An electrolyte ink for ink-jet printing, a solid electrolyte membrane produced using the same, and a secondary battery comprising the solid electrolyte membrane.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolyte ink and a solid electrolyte membrane produced using the electrolyte ink.

An electrolyte ink, and a catalyst ink, a solid electrolyte membrane formed using the same, and a solid electrolyte membrane. More specifically, the present invention discloses an electrolyte ink and a catalyst ink for producing a solid electrolyte membrane, a solid electrolyte membrane produced using the same, and a secondary battery comprising the solid electrolyte membrane.

BACKGROUND ART [0002] Secondary batteries are widely used as power sources for portable portable devices such as mobile phones, personal digital assistants (PDAs), and portable multimedia players (PMPs), motors for driving motors in hybrid vehicles for high output, electric vehicles, , Electronic paper (e-paper), flexible liquid crystal display (LCD), flexible organic diode (OLED), and the like.

Examples of the solid electrolyte used in the secondary battery include a pre-solid electrolyte formed from PEO, PPO (ion conductive polymer) and the like containing a lithium salt; Gel polymer electrolyte formed from PVC, PAN, PMMA, PVdF (non-ion conductive polymer) and the like; And LiPON for a vapor-deposited thin film battery. In order to produce a solid electrolyte, it is usually necessary to apply or print an ink containing a lithium salt, an ion conductive polymer, and a solvent in a liquid phase, followed by drying the solvent. In order to prepare a gel polymer electrolyte, a process of cross-linking the host polymer by heat or UV curing method is generally required for an ink containing a lithium salt, a nonionic conductive host polymer, a solvent and a polymerization initiator. Further, in order to produce LiPON for a thin film battery for deposition, a process of sputtering using Li ₃ PO ₄ as a target is required.

According to one embodiment of the present invention, an electrolyte ink and a catalyst ink for producing a solid electrolyte membrane are provided.

According to another embodiment of the present invention, there is provided a method of manufacturing a solid electrolyte membrane using the above-described electrolyte ink and catalyst ink.

According to another embodiment of the present invention, there is provided a solid electrolyte membrane produced by the above-described production method and a secondary battery using the electrolyte membrane.

The electrolyte ink according to one embodiment of the present invention includes a lithium salt, a solvent, and a cycloolefin-based monomer dispersed in the solvent.

The cycloolefin-based monomer may be a norbornene-based monomer or a dicyclopentadiene-based monomer.

The catalyst ink according to one embodiment of the present invention includes an organic solvent and a catalyst dispersible in the organic solvent capable of promoting the ring-opening and polymerization reaction of the cycloolefin-based monomer.

The catalyst may be a gulose catalyst.

According to another embodiment of the present invention, there is provided a method of manufacturing a solid electrolyte membrane, comprising: printing the catalyst ink on the electrode; Drying the printed catalyst ink; Printing the electrolyte ink on the area of the electrode where the catalyst ink is printed; And forming a ring-opening polymer of a cycloolefin monomer in the electrolyte ink.

The catalyst ink may be directly printed on the electrode coated with the active material.

According to another embodiment of the present invention, there is provided a method of manufacturing a solid electrolyte membrane, comprising: printing the electrolyte ink on an electrode; Printing the catalyst ink on the area of the electrode where the electrolyte is printed; And forming a ring-opening polymer of a cycloolefin monomer in the electrolyte ink.

A solid electrolyte membrane according to another embodiment of the present invention is manufactured by the above-described manufacturing method.

The solid electrolyte membrane according to another embodiment of the present invention includes a lithium salt, a solvent, and a ring-opening polymer of a cycloolefin-based monomer.

The ring-opening polymer of the cycloolefin-based monomer may be a ring-opening polymer of a norbornene-based monomer or a ring-opening polymer of a dicyclopentadiene-based monomer.

The secondary battery according to another embodiment of the present invention includes a positive electrode and a negative electrode, and the above-described solid electrolyte membrane is interposed between the positive electrode and the negative electrode.

According to one embodiment of the present invention, a solid electrolyte membrane having a predetermined pattern and excellent contact with an electrode can be produced using electrolyte ink and catalyst ink, and a thin micro-secondary battery can be manufactured.

Hereinafter, the electrolyte ink and catalyst ink for producing the solid electrolyte membrane will be described in detail.

The electrolyte ink according to an embodiment of the present invention includes a lithium salt, a solvent, and a cycloolefin-based monomer dispersed in the solvent.

The electrolyte ink may be inkjet printed. In this case, the electrolyte ink may have a viscosity of 100 mPa · sec or less at a temperature of 25 ° C and a shear rate of 1000 sec ^-1 . For example, the electrolyte ink may have a viscosity of 2 to 6 mPa · sec at a temperature of 25 ° C and a shear rate of 1000 sec ^-1 .

As the solvent contained in the electrolyte ink, a mixed solvent of a high-k solvent and a low-boiling solvent may be included as a solvent having a high ionic conductivity and a high dielectric constant and a low viscosity. The high-k solvent is not particularly limited as long as it is used in the art. For example, cyclic carbonate such as ethylene carbonate, propylene carbonate, butylene carbonate or gamma-butyrolactone can be used. The low boiling point solvent is also commonly used in the art, and examples thereof include chain carbonates such as dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate and dipropyl carbonate, dimethoxyethane, diethoxyethane and fatty acid ester derivatives. , And is not particularly limited. The mixing volume ratio of the high-permittivity solvent and the low-boiling solvent is preferably 1: 1 to 1: 9 in terms of discharge capacity and charge / discharge life.

The lithium salt dissolved in the mixed solvent may be any lithium salt that is commonly used in lithium batteries and may be LiClO ₄ , LiCF ₃ SO ₃ , LiPF ₆ , LiN (CF ₃ SO ₂ ), LiBF ₄ , LiC (CF ₃ SO ₂ ) ₃ , and LiN (C ₂ F ₅ SO ₂ ) ₂ . The concentration of the lithium salt in the mixed solvent is preferably about 0.5 to 2 M in order to prevent the ion mobility of the electrolyte due to the viscosity of the electrolytic solution while keeping the ionic conductivity of the electrolyte membrane high.

The electrolyte ink according to an embodiment of the present invention is prepared by adding a cycloolefin-based monomer capable of ring-opening and polymerization reaction to a solvent in which the lithium salt is dissolved. The cycloolefin-based monomer decomposes the double bond of the ring (ring-opening reaction) by the catalyst contained in the catalyst ink described later, and then initiates the polymerization between the ring-opened cycloolefin-based monomers. Since the electrolyte can be solidified as the polymer is formed, the curing process required in the process of manufacturing a conventional gel electrolyte is not necessary. Further, since the electrolyte ink containing the cycloolefin-based monomer has a viscosity lower than that of a conventional electrolyte ink containing a polymer, handling of the solid electrolyte membrane is easy.

The content of the cycloolefin-based monomer may be 0.5 to 10% by weight based on the weight of the electrolyte ink. A solid electrolyte membrane having excellent strength can be obtained at a content of 0.5% by weight or more, and the content is preferably 10% by weight or less in terms of solubility in a solvent and characteristics of an electrolyte.

As the cycloolefin-based monomer capable of ring opening and polymerization, a norbornene-based monomer or a dicyclopentadiene-based monomer may be used.

The norbornene-based monomer used in one embodiment of the present invention may be a compound represented by the following formula (1): < EMI ID =

In this formula,

R ₁ to R ₁₀ each independently represent a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, an amino group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, Or a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C7-C30 aryl Substituted or unsubstituted C1-C20 alkyl group, substituted or unsubstituted C6-C30 alkylaryl group, substituted or unsubstituted C1-C20 heteroalkyl group, substituted or unsubstituted C4-C30 heteroaryl group, , An alkyloxycarbonyl group having 2 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, or an alkylcarbonyloxy group having 2 to 20 carbon atoms,

R ₄ and R ₅ together may form = O,

R ₇ and R ₉ may be connected to each other to form a 5-membered or 6-membered ring or a heterocyclic structure,

R ₈ and R ₁₀ may together represent an additional bond between the carbon atoms to which R ₇ and R ₉ are attached.

In the formula 1, R ₇ and R ₉ are bonded to each other to form a cyclic structure, for example, a dicyclopentadiene-based monomer represented by the following formula 2:

In this formula,

R ₁ 'to R ₁₂ ' each independently represent a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, an amino group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms Substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C7- A substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted heteroaryl group having 4 to 30 carbon atoms,

R ₄ 'and R ₅ ' may together form = O,

R ₁₀ 'and R ₁₁ ' may together form = O.

The alkyl group having 1 to 20 carbon atoms as the substituent used in the above formulas (1) and (2) has a linear or branched structure and preferably has 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 Lt; / RTI > to 4 are preferred. Specific examples thereof include methyl, ethyl, propyl, isobutyl, sec-butyl, tert-butyl, pentyl, iso-amyl and hexyl. At least one hydrogen atom contained in the alkyl group may be substituted with a halogen atom, , Cyano group, and the like.

An alkoxy group having 1 to 20 carbon atoms, which is a substituent used in formulas (1) and (2), has a structure of -O-alkyl, and the oxygen atom is bonded to the main chain. The alkoxy group is preferably an alkoxy group having 1 to 12 carbon atoms, more preferably an alkoxy group having 1 to 8 carbon atoms, and most preferably an alkoxy group having 1 to 4 carbon atoms. Examples of such an alkoxy group include a methoxy group, an ethoxy group, and a propoxy group, and at least one hydrogen atom contained in the alkoxy group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

The alkenyl group having 2 to 20 carbon atoms, which is a substituent used in formulas (1) and (2), has a straight-chain or branched structure and means that at least one unsaturated double bond is contained in the alkyl group defined above. The at least one hydrogen atom contained in the alkenyl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

The alkynyl group having 2 to 20 carbon atoms, which is a substituent used in formulas (1) and (2), has a straight-chain or branched structure and means that at least one unsaturated triple bond is contained in the alkyl group defined above. The at least one hydrogen atom contained in the alkynyl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

The aryl group having 6 to 30 carbon atoms as a substituent means an aromatic ring system having at least one aromatic ring and is preferably an aryl group having 6 to 20 carbon atoms and more preferably an aryl group having 6 to 10 carbon atoms. The aromatic rings may be attached together or fused by a pendant method. At least one hydrogen atom of the aryl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like. Specific examples of such an aryl group include a phenyl group, a halophenyl group (e.g., o-, m- and p-fluorophenyl group, dichlorophenyl group), a cyanophenyl group, a dicyanophenyl group, a trifluoromethoxyphenyl group, M-, and p-cumyl groups, o-, m-, and p-cumenyl groups, mesityl groups, phenoxyphenyl groups, (N, N'-diphenyl) aminophenyl group, a pentalenyl group, an indenyl group, a naphthyl group, a halonaphthyl group (for example, (For example, fluoronaphthyl group), a C1-C10 alkylnaphthyl group (for example, methylnaphthyl group), a C1-C10 alkoxynaphthyl group (for example, methoxynaphthyl group), a cyanonaphthyl group, An acenaphthyl group, a phenanthryl group, a fluorenyl group, an anthraquinolyl group, a methylanthryl group, a phenanthryl group, a triphenylene group, a pyrenyl group, A cyclopentadienyl group, a cyclopentadienyl group, a cyclopentadienyl group, a cyclopentadienyl group, a cyclopentadienyl group, a cyclopentadienyl group, a cyclopentadienyl group, a cyclopentadienyl group, A trinaphthyl group, a hepthenyl group, a heptacenyl group, a pyranthrenyl group, an obarenyl group and the like.

The alkylaryl group having 7 to 30 carbon atoms as the substituent means that at least one of the hydrogen atoms of the aryl group defined above is substituted with an alkyl group. For example, a benzyl group, but are not limited thereto. At least one hydrogen atom of the alkylaryl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

The arylalkyl group having 7 to 30 carbon atoms as a substituent means that at least one of the hydrogen atoms of the alkyl group defined above is substituted with an aryl group. For example, 4-tert-butylphenyl group, 4-ethylphenyl group and the like, but are not limited thereto. At least one hydrogen atom of the arylalkyl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

The heteroalkyl group having 1 to 20 carbon atoms as a substituent means that the main chain of the alkyl group defined above contains a hetero atom such as an oxygen atom, a nitrogen atom, a sulfur atom or a phosphorus atom. At least one hydrogen atom of the heteroalkyl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

A heteroaryl group having 4 to 30 carbon atoms as a substituent is a system composed of at least one aromatic ring having at least one hetero atom selected from a hetero atom, for example, an oxygen atom, a nitrogen atom, a sulfur atom and a phosphorus atom and the remaining ring atoms are carbon atoms Thus, the at least one aromatic ring may be fused to each other, or may be connected via a single bond or the like. At least one hydrogen atom of the heteroaryl group may be substituted with a halogen atom, a hydroxy group, a nitro group, a cyano group, or the like.

The arylcarbonyl group as a substituent has the form of aryl-C (= O) -, wherein the aryl group is as defined above.

The substituent alkyloxycarbonyl group has the form of alkyl-O- (C = O) -, wherein the alkyl group is as defined above.

The substituent alkylcarbonyl group has the form of alkyl- (C = O) -, wherein the alkyl group is as defined above.

The substituent alkylcarbonyloxy group has the form of alkyl- (C = O) -O-, wherein the alkyl group is as defined above.

Specific examples of the norbornene-based monomer represented by the formula (1) include norbornene, 2-benzoyl-5-norbornene, ethyl 5-norbonene- 2-yl acetate, cis-5-norbornene-exo-2,3-dicarboxylic acid anhydride, dimethyl exo- tricyclo (4.2.1.0 (2.5) 3,7-diene-3,4-dicarboxylate, and the like, but are not limited thereto.

Norbornen

2-benzoyl-5-norbornene

Ethyl 5-norbonen-2-carboxylate

2-acetyl-5-norbornene

5-norbonen-2-yl acetate

 cis-5-norbornene-exo-2,3-dicarboxylic anhydride

Dimethyl exo-tricyclo (4.2.1.0 (2.5) nona-3,7-diene-3,4-dicarboxylate

Specific examples of the dicyclopentadiene-based monomer represented by Formula 2 include dicyclopentadiene represented by the following structural formulas, 3a, 4,7,7a-tetrahydro-4,7-methano-indene- 1,8-dione, methyldicyclopentadiene dimer, and the like, but are not limited thereto.

Dicyclopentadiene

3a, 4,7,7a-tetrahydro-4,7-methano-indene-1,8-dione

Methyl dicyclopentadiene dimer

In an embodiment of the present invention, the electrolyte ink may further contain an appropriate amount of a dispersant, a moisturizer, a buffer, etc., if necessary, and the components and the content thereof can be selected by those skilled in the art. Do not describe.

The catalyst ink according to an embodiment of the present invention includes an organic solvent and a catalyst dispersible in the organic solvent capable of promoting the ring-opening and polymerization reaction of the cycloolefin-based monomer described above.

As catalysts capable of promoting the ring-opening and the polymerization reaction, preferably Grubbs catalysts as disclosed in US 6,111,121 can be used, and all types of Guruv catalysts disclosed can be used, 1 < / RTI > or 2 < nd > gas catalysts can be used, and specifically include compounds represented by the following structural formulas:

The catalyst ink according to an embodiment of the present invention includes an organic solvent so that the catalyst can be printed by dispersing and inking the catalyst. The organic solvent which can be used as a solvent for the catalyst ink is not particularly limited as long as it can disperse the catalyst. Specific examples thereof include ethanol (EtOH), methanol (MeOH), propanol (PrOH), butanol (BuOH), isopropyl alcohol IPA), and isobutyl alcohol; Polar solvents such as dimethylacetamide (DMAC), dimethylformamide (DMF), dimethylsulfoxide (DMSO), tetrahydrofuran (THF), triethylphosphate and trimethylphosphate; Saturated hydrocarbons such as hexane; Aromatic hydrocarbons such as toluene and xylene; Ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK) and diisobutyl ketone; Esters such as ethyl acetate and butyl acetate; Ethers such as dioxane and diethyl ether; Or a mixed solvent containing two or more of them may be used. The content of the catalyst is preferably 0.1 to 20% by weight based on the catalyst ink.

The catalyst ink according to an embodiment of the present invention may be ink-jet printed. In this case, the catalyst ink may have a viscosity of 100 mPa · sec or less at a temperature of 25 ° C. and a shear rate of 1000 sec ^-1 . For example, the catalyst ink may have a viscosity of 2 to 6 mPa · sec at a temperature of 25 ° C and a shear rate of 1000 sec ^-1 .

Hereinafter, a method for producing a solid electrolyte membrane using the electrolyte ink and the catalyst ink will be described with reference to FIGS. 2 and 3. FIG.

A method of manufacturing a solid electrolyte membrane according to an embodiment of the present invention includes: printing the catalyst ink described above on an electrode, as schematically shown in FIG. 2; Drying the printed catalyst ink; Printing an electrolyte ink containing the cycloolefin-based monomer described above on a region of the electrode where the catalyst ink is printed; And forming a ring-opening polymer of a cycloolefin monomer in the electrolyte ink.

First, the catalyst ink is printed at the position where the electrolyte membrane is to be formed. Preferably, the catalyst ink may be directly discharged onto the electrode coated with the active material. When the catalyst ink is discharged onto the electrode, the catalyst contained in the catalyst ink permeates between the active material particles of the electrode.

The printed catalyst ink is preferably dried in a vacuum atmosphere at 20 to 200 ° C for 1 minute to 8 hours to remove the solvent, but is not limited thereto.

The electrolyte ink is printed on the catalyst ink on which the solvent is dried. When the electrolyte ink is printed, the ring-opened and polymerized reaction of the cycloolefin-based monomer contained in the electrolyte ink is initiated by the catalyst printed on the electrode, and a film composed of such a ring-opening polymer is formed, thereby forming a solid electrolyte film on the electrode.

A method of manufacturing a solid electrolyte membrane according to another embodiment of the present invention includes the steps of: printing the above-described electrolyte ink on an electrode, as schematically shown in FIG. 3; Printing the catalyst ink on the area of the electrode where the electrolyte ink is printed; And forming a ring-opening polymer of a cycloolefin monomer in the electrolyte ink.

The above method is different from the above-described method of producing the solid electrolyte membrane in the order of printing the catalyst ink and the electrolyte ink.

In the method for producing a solid electrolyte membrane, the step of forming the ring-opening polymer may be performed at room temperature.

According to one embodiment of the present invention, the solid electrolyte membrane can be manufactured by the ink jet printing method using the catalyst ink and the electrolyte ink described above instead of the conventional slurry coating. The inkjet method is a method in which electrode ink is printed on a current collector as droplets from a nozzle of an inkjet printer. The inkjet method includes a thermal driving method, a piezoelectric element method, and the like, but it is preferable to use the piezoelectric element method in view of the thermal stability of the battery material. A method of printing by an inkjet method is not particularly limited. For example, an inkjet printer using an inkjet head can be connected to a commercially available computer and printed in a predetermined pattern by legitimate software.

Generally, in the method for producing a solid electrolyte membrane, an initiator must be added for heat or UV curing, and complicated processes such as photoresist, exposure, and development are required for patterning. According to the method for producing a solid electrolyte membrane according to an embodiment of the present invention, when the above-described electrolyte ink is printed by an inkjet method, a solid electrolyte membrane having a predetermined pattern is formed and a separate curing process is unnecessary.

According to the method for producing a solid electrolyte membrane according to an embodiment of the present invention, since a solid electrolyte membrane can be formed by an ink-jet printing method, all processes of manufacturing a battery can be performed by an inkjet printing method.

The solid electrolyte membrane according to another embodiment of the present invention includes a ring-opening polymer of a cycloolefin-based monomer impregnated with a solvent containing a lithium salt. The ring-opening polymer of the cycloolefin-based monomer may be a ring-opening polymer of a norbornene monomer represented by the following formula (3) or a ring-opening polymer of a dicyclopentadiene-based monomer represented by the following formula (4).

Wherein R ₁ to R ₁₀ are the same as defined in Formula (1), and n is an integer of 1 or more. With respect to the upper limit of n, ring-opening polymerization of an infinite number of norbornene monomers may be performed depending on the amount of the catalyst and the like. Therefore, n can be appropriately selected by those skilled in the art by changing the amount of the catalyst and the like.

Wherein R ₁ 'to R ₁₂ ' are as defined in Chemical Formula 2, and n and k are an integer of 1 or more. With respect to the upper limits of n and k, ring-opening polymerization of an infinite number of dicyclopentadiene-based monomers can be made depending on the amount of catalyst and the like. Therefore, n can be appropriately selected by those skilled in the art by changing the amount of the catalyst and the like.

Since the catalyst contained in the catalyst ink during the production of the solid electrolyte membrane permeates between the electrode active materials, ring opening and polymerization of the cycloolefin-based monomer by the catalyst can also be performed in the region between the electrode active materials. Therefore, the solid electrolyte membrane obtained from ring-opening and polymerization reaction has an increased contact area with the electrode, and is excellent in electrode electrochemical interface property, that is, contact with the electrode.

Hereinafter, a configuration of the secondary battery including the above-described electrolyte membrane will be described as an example.

1, a secondary battery according to an embodiment of the present invention includes a positive electrode 13, a negative electrode 15, and a solid electrolyte membrane 14 interposed between the positive electrode 13 and the negative electrode 15 . The anode 13 is formed on the anode current collector 12 patterned on the substrate 11. On the other hand, a negative current collector 16 is formed on the substrate 12. On the cathode (16), a protective film (17) is applied.

Such a lithium battery can be formed by the following manufacturing method.

First, metal inks for forming positive and negative current collectors are prepared, respectively. The metal ink is carried on the inkjet print cartridge, printed on the substrate 11 in a desired pattern and thickness, and then heat treated in the range of, for example, 100 to 600 ° C to form current collectors 12 and 16. Next, the electrode is printed on the current collector with a desired pattern and thickness with the anodic oxide ink, and is heat-treated, for example, in the range of 100 to 150 DEG C to form the anode 13. [ Then, the catalyst ink described above is printed at a position where the electrolyte is to be applied. When the solvent is dried, the above-described electrolyte ink is printed and polymerization reaction is performed for a predetermined time to form the solid electrolyte membrane 14. [ At this time, the order of printing the electrolyte ink and the catalyst ink may be changed. Then, the negative electrode 15 is formed by sequentially printing an anode oxide ink and drying the solvent, and then the protective film 17 is applied thereon to complete the secondary battery 10. As described above, all the constitutions of the lithium battery can be easily formed by an ink-jet printing method.

The metal fine particles contained in the metal ink may be any of ordinary metals used as current collectors of the secondary battery. Preferably, the positive electrode current collector includes Al, Ni, Fe (SUS), Ag, As the current collector, Cu, Fe (SUS), Ni and the like are preferable.

The electrode oxide ink was prepared by sequentially mixing an appropriate amount of oxide particles, a conductive agent, a solvent, and a binder, and then performing a ball mill and a bead mill in that order and sequentially passing through a 1 μm and 0.45 μm polytetrafluoroethylene (PTFE) syringe filter .

The oxide particles can be any of ordinary oxide particles used as the electrode active material of the secondary battery. Examples of the usable cathode active material include Li-Co composite oxides such as LiCoO ₂ , Li-Ni composite oxides such as LiNiO ₂ , Li-Mn composite oxides such as LiMn ₂ O ₄ and LiMnO ₂ , Li ₂ Cr ₂ O ₇ , Li ₂ CrO ₄ , a Li-Fe composite oxide such as LiFeO ₂ , and a Li-V composite oxide. Using as a possible negative active material _{Li 4 Ti 5 O 12 Li-} Ti based composite oxides such _{as, SnO 2, In 2 O 3} , Sb2O 3 including the transition metal oxide, graphite, hard carbon, acetylene black, and carbon such as carbon black . The content of the suitable oxide particles is preferably 0.1 to 10% by weight, more preferably 3 to 7% by weight of the total ink. In this range, the printing efficiency is excellent, the coagulation phenomenon between the particles can be prevented, and the stability and dischargeability of the ink are excellent.

As the conductive agent for improving the conductivity of the oxide particles, acetylene black, carbon black, graphite, carbon fiber, carbon nanotubes and the like can be used. The content of the conductive agent is preferably 1 to 20% by weight of the oxide particles.

The electrode oxide ink may further include a dispersing agent for dispersing the oxide particles and the conductive agent. Non-limiting examples of usable dispersing agents include fatty acid salts, alkyldicarboxylic acid salts, alkylsulfuric acid ester salts, polyvalent sulfuric acid ester alcohol salts, alkylnaphthalene sulfate, alkylbenzene sulfate, alkylnaphthalene sulfate ester salts, alkylsulfone succinate, An alkyl ether carboxylate, an acylated peptide, an alpha olefin sulfate, an N-acyl methyl taurate salt, an alkyl ether sulfate, a secondary alcohol alcohol ethoxy sulfate, a polyoxyethylene alkyl peryl ether sulfate, a monoglyceryl sulfate, Alkylamine salts, alkylpyridinium salts, alkylimidazolium salts, fluorine-based or silicone-based acrylic acid polymers, polyoxyethylene alkyl ethers, polyoxyethylene sterol ethers, lanolin derivatives of polyoxyethylene, Polyoxyethylene / polyoxypropylene copolymers, polyoxyethylene sorbitan fatty acid esters, monoglycerides A polyoxyethylene alkylamine, a polyvinyl alcohol, a polyvinyl pyridone, a polyacrylamide, a carboxyl group-containing water-soluble polyester, a hydroxyl group-containing cellulose One or two kinds of conventional dispersing agents such as an acrylic resin, an acrylic resin, an acrylic resin, a butadiene resin, an acrylic acid type, a styrene acrylic type, a polyester type, a polyamide type, a polyurethane type, an alkyl betamine, an alkylamine oxide, a phosphatidylcholine, Or more. The content of the dispersing agent is preferably 1 to 20% of the oxide particles, but may not be added considering the characteristics of the electrode and the dispersibility.

The electrode oxide ink may include a binder for imparting an adhesion force between the ink fine particles and the electrode plate after inkjet printing. Examples of usable binders include polyvinyl alcohol, an ethylene-propylene-diene terpolymer, styrene-butadiene rubber, polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoro Propylene copolymer, and carboxymethylcellulose, and polyvinylidene fluoride (PVdF) is preferable.

(EtOH), methanol (MeOH), propanol (PrOH), and butanol (NMP) as the main components, BuOH), isopropyl alcohol (IPA), and isobutyl alcohol; (DMAC), dimethylformamide (DMF), dimethylsulfoxide (DMSO), tetrahydrofuran (THF), triethylphosphate, trimethylphosphate and the like to increase the precision and resolution of the pattern. They can be mixed with each other at various ratios according to purpose and purpose. Further, saturated hydrocarbons such as hexane and the like; Aromatic hydrocarbons such as toluene and xylene; Ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK) and diisobutyl ketone; Esters such as ethyl acetate and butyl acetate; Ethers such as dioxane and diethyl ether; Or the like may be further mixed and used.

The secondary battery according to an embodiment of the present invention can be bent and formed into a thin and light shape by using the solid electrolyte film formed by the ink jet printing method using the electrolyte ink and the catalyst ink described above, Available.

Hereinafter, the present invention will be described by way of examples and comparative examples. However, these examples are for illustrative purposes only, and the claims are not limited to these examples.

Example 1

To the mixed solvent of 70 wt% of N-methyl-2-pyrrolidone (NMP), 20 wt% of ethanol (EtOH) and 5 wt% of diethylene glycol (DEG), 4.65 wt% of LiCoO ₂ , 0.15 wt , And 0.2% by weight of polyvinylidene fluoride (PVdF) were mixed and dispersed in a paint shaker using zirconia beads having a diameter of 0.3 mm for 2 hours. Then, a 1 탆 and 0.45 탆 polytetrafluoroethylene (PTFE) syringe filter was sequentially passed to complete the electrode ink. The electrode ink was printed on an aluminum foil using an ink jet printer (Fuji Dimatix DMP-2800) to form an electrode.

(Viscosity: 3.528 mPa · sec at a shear rate of 1000 s ^-1 ) by adding 5 wt% of a catalyst (manufactured by Sigma Aldrich Co., Ltd., product name: GRUPS Catalyst) to ethanol (EtOH) The printed electrode was printed in the same form and dried at 60 DEG C for 10 minutes to remove the solvent.

Ethylene carbonate and diethylene carbonate were mixed in a volume ratio of 3: 7 to prepare an electrolytic solution by adding 1.3 M of LiPF ₆ , and 5 wt% of dicyclopentadiene was further added to complete the electrolyte ink (shear rate Viscosity at 1000 s ^-1 : 4.475 mPa · sec). The electrolyte ink was discharged onto the above-mentioned gas catalyst ink printed using the inkjet printer to form a solid electrolyte membrane.

Thus, a coin cell (CR2016 type) of the 2016 standard was prepared by forming a positive electrode and an electrolyte film, and using a lithium metal as a counter electrode as a negative electrode. The obtained coin cell was charged with a constant current until a voltage of 4.3 V was applied to the lithium electrode at a current rate of 0.1 C, and then the constant current was charged at a constant voltage of 0.05 C with respect to the cell capacity while maintaining a voltage of 4.3 V Respectively. Then, a constant current discharge was performed at a current of 0.1 C at the cell capacity until the voltage reached 3.0 V, and the result of the charge-discharge test was shown by a curve in FIG.

Example 2

To the mixed solvent of 70 wt% of N-methyl-2-pyrrolidone (NMP), 20 wt% of ethanol (EtOH) and 5 wt% of diethylene glycol (DEG), 4.65 wt% of LiCoO ₂ , 0.15 wt , And 0.2% by weight of polyvinylidene fluoride (PVdF) were mixed and dispersed in a paint shaker using zirconia beads having a diameter of 0.3 mm for 2 hours. Then, a 1 탆 and 0.45 탆 polytetrafluoroethylene (PTFE) syringe filter was sequentially passed to complete the electrode ink. The electrode ink was printed on an aluminum foil using an ink jet printer (Fuji Dimatix DMP-2800) to form an electrode.

(Viscosity at a shear rate of 1000 s ^-1 : 3.528 mPa · sec) in ethanol (EtOH) by adding 5 wt% of a glucose catalyst and then printing on the printed electrode in the same manner using the inkjet printer (60) < 0 > C for 10 minutes to remove the solvent.

Ethylene carbonate and diethylene carbonate were mixed in a volume ratio of 3: 7 to prepare an electrolytic solution by adding 1.3M of LiPF ₆ to the mixture. Further, 5 wt% of norbornene was added to complete the electrolyte ink (shear rate 1000 s ^-1 : 3.928 mPa · sec). The solid electrolyte membrane was formed by discharging the electrolyte ink using the above-described ink jet printer on which the gas catalyst ink was printed.

Thus, a coin cell (CR2016 type) of the 2016 standard was prepared by forming a positive electrode and an electrolyte film, and using a lithium metal as a counter electrode as a negative electrode. The obtained coin cell was charged at a constant current of 0.1 C at a constant current until reaching 4.3 V with respect to the Li electrode, and then the constant current was charged at a constant rate of 0.05 C with respect to the cell capacity while maintaining a voltage of 4.3 V. Then, a constant-current discharge was performed at a current of 0.1 C at the cell capacity until the voltage reached 3.0 V, and the result of the charge-discharge test was shown by a curve in FIG.

Comparative Example 1

A coin cell was prepared in the same manner as in Example 1 except that no grospinous catalyst ink was applied and dicyclopentadiene was not added to the electrolyte ink. Fig. 6 shows the charge / discharge test results of the obtained coin cell.

Referring to FIGS. 4, 5 and 6, it can be seen that the secondary battery of the embodiment shows a charge / discharge capacity similar to that of the secondary battery of the comparative example. As described above, by using the electrolyte ink and the catalyst ink according to one embodiment of the present invention, the solid electrolyte membrane can be manufactured by the ink jet method while maintaining the normal battery characteristics.

1 is a schematic cross-sectional view of a secondary battery according to an embodiment of the present invention.

2 is a view showing a method for producing a solid electrolyte membrane according to an embodiment of the present invention.

3 is a view showing a method for producing a solid electrolyte membrane according to another embodiment of the present invention.

FIG. 4 is a diagram showing charge / discharge curves of a secondary battery according to Example 1. FIG.

5 is a diagram showing charge / discharge curves of a secondary battery according to Embodiment 2

FIG. 6 is a graph showing charge / discharge curves of a secondary battery according to Comparative Example 1. FIG.

Claims (33)

1. An electrolyte ink capable of inkjet printing, A lithium salt, a solvent, and a ring-opening polymer forming monomer dispersed in the solvent, Wherein the ring opening polymer forming monomer comprises a cycloolefin-based monomer. delete  The method according to claim 1, Wherein the electrolyte ink has a viscosity of 100 mPa 占 퐏 or less at a temperature of 25 占 폚 and a shear rate of 1000 sec < ^-1 >.  The method of claim 3, Wherein the electrolyte ink has a viscosity of 2 to 6 mPa · sec at a temperature of 25 ° C and a shear rate of 1000 sec ^-1 .  The method according to claim 1, Wherein the cycloolefin-based monomer is contained in an amount of 0.5 to 10% by weight. The method according to claim 1, Wherein the cycloolefin-based monomer is a norbornene-based monomer or a dicyclopentadiene-based monomer. The method according to claim 6, Wherein the norbornene monomer is a compound represented by the following formula (1): [Chemical Formula 1]

In this formula, R ₁ to R ₁₀ each independently represent a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, an amino group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, Or a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, , A substituted or unsubstituted heteroaryl group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 4 to 30 carbon atoms, an arylcarbonyl group having 7 to 30 carbon atoms , An alkyloxycarbonyl group having 2 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms, or an alkylcarbonyloxy group having 2 to 20 carbon atoms, R ₄ and R ₅ together may form = O, R ₇ and R ₉ may be connected to each other to form a 5-membered or 6-membered ring or a heterocyclic structure, R ₈ and R ₁₀ may together represent an additional bond between the carbon atoms to which R ₇ and R ₉ are attached. The method according to claim 6, The norbornene-based monomer may be at least one selected from the group consisting of norbornene, 2-benzoyl-5-norbornene, ethyl 5-norbonen-2-carboxylate, 2-acetyl- Dicarboxylic acid anhydride and dimethyl exo-tricyclo (4.2.1.0 (2.5) nona-3,7-diene-3, 4-dicarboxylate from the group consisting of 5-norbornene- Wherein at least one selected compound is an electrolyte ink. The method according to claim 6, Wherein the dicyclopentadiene-based monomer is a compound represented by the following formula (2): (2)

In this formula, R ₁ 'to R ₁₂ ' each independently represent a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, an amino group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms Substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C7- A substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted heteroaryl group having 4 to 30 carbon atoms, R ₄ 'and R ₅ ' may together form = O, R ₁₀ 'and R ₁₁ ' may together form = O. The method according to claim 6, The dicyclopentadiene-based monomer is selected from the group consisting of dicyclopentadiene, 3a, 4,7,7a-tetrahydro-4,7-methano-indene-1,8-dione and methylcyclopentadiene dimer Wherein at least one compound is an electrolyte ink. As a catalyst ink for forming a solid polymer membrane capable of inkjet printing, Organic solvent; And a catalyst capable of promoting the ring-opening and polymerization reaction of the cycloolefin-based monomer dispersed in the organic solvent. delete  12. The method of claim 11, Wherein the catalyst ink has a viscosity of 100 mPa · sec or less at a temperature of 25 ° C and a shear rate of 1000 sec ^-1 . 14. The method of claim 13, Wherein the catalyst ink has a viscosity of 2 to 6 mPa · sec at a temperature of 25 ° C and a shear rate of 1000 sec ^-1 . 12. The method of claim 11, Wherein the catalyst is contained in an amount of 0.1 to 20% by weight. 12. The method of claim 11, Wherein the catalyst is a Grubbs catalyst. 12. The method of claim 11, The organic solvent may be at least one selected from the group consisting of ethanol (EtOH), methanol (MeOH), propanol, BuOH, isopropyl alcohol (IPA), isobutyl alcohol, dimethylacetamide (DMAC), dimethylformamide (DMSO), tetrahydrofuran (THF), triethylphosphate, trimethylphosphate, hexane, benzene, toluene, xylene, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK) , Diisobutyl ketone, ethyl acetate, butyl acetate, dioxane, and diethyl ether. delete delete Printing a catalyst ink according to any one of claims 11 to 13 on the electrode; Drying the printed catalyst ink; Printing the electrolyte ink according to any one of claims 1 to 10 on the area of the electrode where the catalyst ink is printed; And And forming a ring-opening polymer of a cycloolefin monomer in the electrolyte ink. Printing an electrolyte ink according to any one of claims 1 to 10 on the electrode; Printing the catalyst ink according to any one of claims 11 to 13 on the area of the electrode where the electrolyte ink is printed; And And forming a ring-opening polymer of a cycloolefin monomer in the electrolyte ink. 21. The method of claim 20, Wherein the step of forming the polymer is performed at room temperature. 21. The method of claim 20, Wherein the printing is performed by an ink-jet printing method. 21. The method of claim 20, The catalyst ink Wherein the active material is directly printed on the coated electrode. A solid electrolyte membrane produced according to the method of claim 20. anode, Cathode and And a solid electrolyte membrane according to claim 25 interposed between the anode and the cathode. A solid electrolyte membrane comprising a lithium salt, a solvent, and a ring-opening polymer of a cycloolefin monomer. 28. The method of claim 27, The ring-opening polymer of the cycloolefin-based monomer is a ring-opening polymer of a norbornene monomer or a ring-opening polymer of a dicyclopentadiene-based monomer. 29. The method of claim 28, Wherein the ring-opening polymer of the norbornene monomer is represented by the following general formula (3): < EMI ID = (3)

R ₁ to R ₁₀ each independently represent a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, an amino group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, Or a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, , A substituted or unsubstituted alkylaryl group having 7 to 30 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 4 to 30 carbon atoms, an arylcarbonyl group having 7 to 30 carbon atoms, An alkyloxycarbonyl group having 2 to 20 carbon atoms, an alkylcarbonyl group having 2 to 20 carbon atoms or an alkylcarbonyloxy group having 2 to 20 carbon atoms, R ₄ and R ₅ together may form = O, R ₇ and R ₉ may be connected to each other to form a 5-membered or 6-membered ring or a heterocyclic structure, R ₈ and R ₁₀ may together represent an additional bond between the carbon atoms to which R ₇ and R ₉ are attached, n and k are an integer of 1 or more. 29. The method of claim 28, Wherein the ring-opening polymer of the dicyclopentadiene-based monomer is represented by the following general formula (4) [Chemical Formula 4]

In this formula, R ₁ 'to R ₁₂ ' each independently represent a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, an amino group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms Substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C7- A substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted heteroaryl group having 4 to 30 carbon atoms, R ₄ 'and R ₅ ' may together form = O, R ₁₀ 'and R ₁₁ ' together may form = O, n and k are an integer of 1 or more. 22. The method of claim 21, Wherein the step of forming the polymer is performed at room temperature. 22. The method of claim 21, Wherein the printing is performed by an ink-jet printing method. A solid electrolyte membrane produced according to the method of claim 21.

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