KR20150122347A - Anode Using Gel Polymer, Manufacturing Process and Manufacturing Device thereof - Google Patents

Abstract

The present invention provides a cathode, and a method and apparatus for manufacturing the same. A cathode composite including a cathode activation material, a binder, and a conductive material is applied on a collector. A gel polymer including lithium salt is applied on a cathode composite layer. The gel polymer is formed by optical polymer reaction in a state in which one or more monomers selected from the group consisting of an acrylate monomer, a vinyl monomer, a (meth) acrylic acid ester-based monomer, and a nitrile-based monomer includes the lithium salt. According to the present invention, a battery using the cathode can ensure safety by preventing disconnection. Consequentially, the output and lifetime of the battery are improved.

Description

Technical Field [0001] The present invention relates to an anode using a gel polymer, an anode using the gel polymer,

The present invention relates to a negative electrode using a gel polymer, a method for producing the same, and an apparatus for producing the same.

As technology development and demand for mobile devices are increasing, the demand for secondary batteries as energy sources is rapidly increasing. Among such secondary batteries, lithium secondary batteries having high energy density and voltage have been commercialized and widely used. Such a lithium secondary battery generally uses a lithium transition metal oxide as a cathode active material and a graphite based material as an anode active material.

The safety of such a lithium secondary battery is of the highest priority, and various studies have been made especially for preventing short circuit due to high temperature and overcharge.

As a first method, there is a technique of coating an inorganic film on a separator and a cathode electrode of a lithium secondary battery. In this case, although the safety of the battery is improved, there is a problem that the output and lifetime characteristics are deteriorated as the internal resistance increases.

In the second method, when overcharging occurs, there is a method of mechanically cutting off the current by promoting the generation of gas. However, there is a problem in that an additional electronic circuit is required and the manufacturing cost of the battery is increased.

The final method is to melt the membrane and shut it down. However, to prevent pores in the membrane, the temperature must rise when overcharged. Such a rise in temperature is caused by a reaction between the lithium metal complex oxide of the anode and the lithium metal precipitated on the anode by overcharging and the electrolyte, so that the reaction causes a rapid temperature rise and even if the separation membrane is melted, And there are many restrictions on practical applications.

Therefore, there is a need to solve the above problems and to study the safety and performance of a battery by preventing a short circuit due to overcharging of the battery.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted intensive research and various experiments and have found that when a negative electrode coated with a predetermined gel polymer containing a lithium salt on a negative electrode mixture layer is used, And that the desired effect can be achieved, and have accomplished the present invention.

Accordingly, the present invention provides a negative electrode active material composition comprising a negative electrode active material composition comprising a negative electrode active material, a binder and a conductive material coated on a current collector, and a gel polymer containing a lithium salt is applied on the negative electrode material mixture layer , The gel polymer is characterized in that at least one monomer selected from the group consisting of an acrylate monomer, a vinyl monomer, a (meth) acrylate monomer and a nitrile monomer is formed by a photopolymerization reaction in the state that a lithium salt is contained Is provided.

Since the negative electrode according to the present invention is coated with the gel polymer containing the lithium salt on the negative electrode mixture, it is possible to control the lithium ion inflow passage on the surface of the negative electrode, thereby preventing a short circuit due to damage of the separator during overcharging, And it is possible to prevent deterioration of output and lifetime characteristics due to a decrease in internal resistance, and consequently to improve the performance of the battery using the same.

The content of the lithium salt may be 1 wt% to 30 wt%, more specifically 5 wt% to 20 wt%, and more specifically 5 wt% to 15 wt% based on the total weight of the gel polymer. Lt; / RTI > If the content of the lithium salt is excessively small, the safety effect by controlling the lithium ion inflow passage on the surface of the negative electrode may be deteriorated, and if the content of the lithium salt is excessively large, the internal resistance of the battery may be rather increased.

The lithium salt is not limited as long as it is known in the art. For example, LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , LiAsF ₆ , And at least one selected from the group consisting of LiSbF ₆ , LiAlCl ₄ , CH ₃ SO ₃ Li, (CF ₃ SO ₂ ) ₂ NLi, chloroborane lithium, lower aliphatic carboxylate lithium, and lithium tetraphenylborate.

In one example, the acrylate monomer is selected from the group consisting of methacryloxyethyl ethylene urea,? -Carboxyethyl acrylate, aliphatic monoacrylate, dipropylene diacrylate, ditrimethylpropane tetraacrylate, hydroxyethyl acrylate, But are not limited to, dipentaerythritol hexaacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, lauryl acrylate, seryl acrylate, stearyl acrylate, lauryl methacrylate, Stearyl methacrylate, and stearyl methacrylate.

The (meth) acrylic acid ester monomer may be at least one monomer selected from the group consisting of methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, isoamyl acrylate, n- Ethylhexyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl Methacrylate, n-amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, n-ethylhexyl methacrylate, 2-ethylhexyl methacrylate, hydroxyethyl methacrylate, Propyl methacrylate, and the like.

The vinyl-based monomer may be at least one monomer selected from the group consisting of styrene,? -Methylstyrene,? -Methylstyrene, p-t-butylstyrene, divinylbenzene, and mixtures thereof.

The nitrile monomer may be selected from the group consisting of succinonitrile, cevanonitrile, fluorinated nitrile, nitrile chloride, and the like, preferably one or more monomers selected from the group consisting of acrylonitrile, methacrylonitrile, Lt; / RTI >

Specifically, the gel polymer may be formed by a photopolymerization reaction in which one or more monomers selected from the group consisting of an acrylate monomer, a (meth) acrylic acid ester monomer, and a nitrile monomer are included in a lithium salt have.

The monomers may comprise 5 to 40% by weight of an acrylate monomer, 10 to 50% by weight of a (meth) acrylate monomer, and 20 to 50% by weight of a nitrile monomer, based on the total weight of the monomers, More specifically, the acrylate-based monomer may be 15 to 30 wt%, the (meth) acrylate-based monomer may be 35 to 50 wt%, and the nitrile-based monomer may be 25 to 40 wt%.

The coating thickness of the gel polymer layer containing the lithium salt may be, for example, 0.1 to 1000 micrometers. When the coating thickness of the gel polymer layer containing the lithium salt is too thick or thin, it is not preferable that the lithium ion inflow passage can not be controlled smoothly.

According to the present invention, there is provided a method of manufacturing the negative electrode, comprising the steps of: (A) applying a negative electrode material mixture comprising a negative electrode active material, a binder and a conductive material onto a current collector; (B) applying a monomer solution containing a lithium salt onto the negative electrode mixture layer in the step (A); And (C) photopolymerizing the monomer solution of the step (B) to prepare a gel polymer containing a lithium salt.

As described above, the content of the lithium salt in the monomer solution may be 1 wt% to 30 wt% based on the total weight of the gel polymer.

The solvent is not limited as long as it is known in the art, and examples thereof include aromatic solvents such as toluene and xylene; Ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and 2-methyl-5-hexanone; Ester solvents such as ethyl acetate, butyl acetate, and ethyl lactate; Halogen-based solvents such as methyl chloride, dichloromethane and dichloroethane; Alcohol solvents such as ethanol and isopropanol; Glycol ether solvents such as ethylene glycol ethyl ether, propylene glycol methyl ether, propylene glycol n-propyl ether and propylene glycol methyl ether acetate, cellosolve acetate, methyl cellosolve, ethyl cellosolve, n- Sorb, i-butyl cellosolve, n-propyl cellosolve and the like, and they may be used alone or in combination of two or more. In particular, methyl ethyl ketone and ethyl acetate can be preferably used because they are easy to reduce the residual solvent concentration.

The monomer solution may further include a photopolymerization initiator and the like.

The photopolymerization initiator acts to cause polymerization reaction by light irradiation, and examples thereof include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamino) Benzophenone, 4,4-dichlorobenzophenone, 4-benzoyl-4-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy- , 2-methylpropiophenone, pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthiok Benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butyl anthraquinone, 2-amyl anthraquinone, and? -Chloroanthraquinone It can be one or more of the selected groups.

Such a photopolymerization initiator may include 1% by weight to 20% by weight based on the total weight of the monomer solution.

Generally, in the present invention, photopolymerization can be carried out by irradiating ultraviolet rays. Therefore, monomers which cause polymerization reaction in this range can be preferably used.

The monomer solution may further include oligomers in addition to the respective components.

In particular, an oligomer having a weight average molecular weight of 10,000 or less may be contained in an amount of 1 to 10% by weight based on the total weight of the monomer solution.

The present invention further includes a step of drying after the photopolymerization of the step (C) to remove the remaining solvent after the photopolymerization reaction. In this case, it may be dried using heat or wind of 100 to 300 degrees.

The present invention relates to an apparatus for producing the negative electrode, comprising: (a) a rotating roll for moving a negative electrode sheet coated with a negative electrode mixture composed of a negative electrode active material, a binder and a conductive material on one surface or both surfaces of the current collector; (b) a monomer solution injecting portion for applying the monomer solution onto the coating layer of the negative electrode mixture; (c) a light-directing section for irradiating light to cause photopolymerization of the monomer solution; And (d) a drying unit for drying the negative electrode sheet coated with the gel polymer containing the lithium salt formed by photopolymerization.

When the moving speed of the current collector is excessively high, the photopolymerization reaction of the monomer solution containing lithium salt can not be sufficiently performed, and if it is too slow, the efficiency of the negative electrode manufacturing process is low. Therefore, the movement speed of the current collector may be 5 to 100 cm / sec, and more specifically 10 to 50 cm / sec.

The negative electrode material mixture of the present invention includes a negative electrode active material, a binder, and a conductive material, and further, a viscosity adjusting agent, a filler, a coupling agent, an adhesion promoter, and the like may be added as needed.

Examples of the negative electrode active material include carbon and graphite materials such as natural graphite, artificial graphite, expanded graphite, carbon fiber, non-graphitizable carbon, carbon black, carbon nanotube, fullerene and activated carbon; Metals such as Al, Si, Sn, Ag, Bi, Mg, Zn, In, Ge, Pb, Pd, Pt and Ti which can be alloyed with lithium and compounds containing these elements; Complexes of metals and their compounds and carbon and graphite materials; Lithium-containing nitrides, and the like. Among them, a carbon-based active material, a silicon-based active material, a tin-based active material, or a silicon-carbon based active material is more preferable, and these may be used singly or in combination of two or more.

The binder includes, for example, polyethylene oxide, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichlorethylene, polymethyl methacrylate, polyacrylonitrile, poly Acrylonitrile-styrene copolymer, polyvinyl chloride (PVC), polyvinyl pyrrolidone, polyvinyl acetate, polyethylene vinyl acetate copolymer, gelatin, cyanoethylpullulan, cyanoethylpolyvinyl alcohol, cyanoethylcellulose Cellulose acetate propionate, polyethylene glycol, glyme, polyethylene glycol dimethyl ether, and carboxymethyl cellulose, but it may be limited to only one of them. Being It is not.

The conductive material is a component for further improving the conductivity of the electrode active material and may be added in an amount of 1 to 30% by weight based on the total weight of the electrode mixture. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; Carbon fibers such as carbon nanotubes and fullerene; conductive fibers such as carbon fibers and metal fibers; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The viscosity adjusting agent may be added up to 30% by weight based on the total weight of the electrode mixture, so as to control the viscosity of the electrode mixture so that the mixing process of the electrode mixture and the coating process on the collector may be easy. Examples of such viscosity modifiers include carboxymethylcellulose, polyvinylidene fluoride and the like, but are not limited thereto.

The filler is an auxiliary component for suppressing the expansion of the electrode. The filler is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery, and examples thereof include olefin polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The coupling agent is an auxiliary component for increasing the adhesive force between the electrode active material and the binder. The coupling agent has two or more functional groups and can be used up to 30% by weight based on the weight of the binder. Such a coupling agent can be obtained by, for example, a method in which one functional group reacts with a hydroxyl group or a carboxyl group on the surface of a silicon, a tin, or a graphite active material to form a chemical bond and the other functional group reacts with a polymeric binder to form a chemical bond Lt; / RTI > Specific examples of the coupling agent include triethoxysilylpropyl tetrasulfide, mercaptopropyl triethoxysilane, aminopropyl triethoxysilane, and chloropropyltriethoxysilane ( chloropropyl triethoxysilane, vinyl triethoxysilane, methacryloxypropyl triethoxysilane, glycidoxypropyl triethoxysilane, isocyanatopropyl triethoxysilane, And silane-based coupling agents such as cyanopropyl triethoxysilane, but are not limited thereto.

The adhesion promoter may be added in an amount of 10% by weight or less based on the binder, for example, oxalic acid, adipic acid, Formic acid, acrylic acid derivatives, itaconic acid derivatives, and the like.

The negative electrode current collector is generally made to have a thickness of 3 to 500 mu m. Such an anode current collector is not particularly limited as long as it has conductivity without causing chemical change in the battery, and may be formed of a material such as copper, stainless steel, aluminum, nickel, titanium, fired carbon, surface of copper or stainless steel A surface treated with carbon, nickel, titanium, silver or the like, an aluminum-cadmium alloy, or the like can be used.

The present invention provides a secondary battery including the negative electrode. The secondary battery includes a positive electrode, a negative electrode, a separator, a nonaqueous electrolyte solution containing a lithium salt, and the like. The secondary battery includes an electrode assembly having a positive electrode / separator / negative electrode structure embedded in a battery case.

The positive electrode is prepared, for example, by applying a mixture of a positive electrode active material, a conductive material and a binder on a positive electrode current collector, followed by drying, and if necessary, a viscosity adjusting agent, a filler, a coupling agent, And the like can be further included.

The cathode active material may be a layered compound such as lithium cobalt oxide (LiCoO ₂ ), lithium nickel oxide (LiNiO ₂ ), or a compound substituted with one or more transition metals; Lithium manganese oxides such as Li _{1 + x} Mn _{2 -x} O ₄ (where x is 0 to 0.33), LiMnO ₃ , LiMn ₂ O ₃ , LiMnO ₂ and the like; Lithium copper oxide (Li ₂ CuO ₂ ); Vanadium oxides such as LiV ₃ O ₈ , LiFe ₃ O ₄ , V ₂ O ₅ and Cu ₂ V ₂ O ₇ ; A Ni-site type lithium nickel oxide expressed by the formula LiNi _1-x M _x O ₂ (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga and x = 0.01 to 0.3); Formula _{LiMn 2-x M x O 2} ( where, M = Co, Ni, Fe , Cr, and Zn, or Ta, x = 0.01 ~ 0.1 Im) or Li ₂ Mn ₃ MO ₈ (where, M = Fe, Co, Ni, Cu, or Zn); LiMn ₂ O _{4 in} which a part of Li in the formula is substituted with an alkaline earth metal ion; Disulfide compounds; Fe ₂ (MoO ₄ ) ₃ , and the like. However, the present invention is not limited to these.

Other components of the positive electrode material mixture, such as the conductive material, the binder, and the like, are as defined above.

        The cathode current collector generally has a thickness of 3 to 500 mu m. Such a positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical change in the battery, and may be formed of a material such as stainless steel, aluminum, nickel, titanium, sintered carbon, or a surface of aluminum or stainless steel Treated with carbon, nickel, titanium, silver or the like may be used.

These current collectors may be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, a non-woven fabric, or the like, by forming fine irregularities on the surface of the current collectors to enhance the binding force of the electrode active material.

The pore diameter of the separation membrane is generally 0.01 to 10 mu m and the thickness is generally 5 to 300 mu m. As such a separation membrane, for example, a sheet or a nonwoven fabric made of an olefin-based polymer such as polypropylene which is chemically resistant and hydrophobic, glass fiber, polyethylene or the like is used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The lithium-containing non-aqueous electrolyte is composed of a non-aqueous electrolyte and a lithium salt.

Examples of the nonaqueous electrolytic solution include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, But are not limited to, lactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, Nitrile, nitromethane, methyl formate, methyl acetate, phosphoric acid triester, trimethoxymethane, dioxolane derivatives, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate derivatives , Tetrahydrofuran derivatives, ether, methyl pyrophosphate, ethyl propionate and the like can be used.

The lithium salt is a material which is soluble in the non-aqueous liquid electrolyte and includes, for example, LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , LiAsF _{6, LiSbF 6, LiAlCl 4,} CH 3 SO 3 Li, CF 3 SO 3 Li, (CF 3 SO 2) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide have.

In some cases, organic solid electrolytes, inorganic solid electrolytes, etc. may be used.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, Polymers containing ionic dissociation groups, and the like can be used.

Examples of the inorganic solid electrolyte include Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides, sulfates and the like of Li such as Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS ₂ can be used.

For the purpose of improving the charge-discharge characteristics and the flame retardancy, the non-aqueous liquid electrolyte may contain, for example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, N, N-substituted imidazolidine, ethylene glycol dialkyl ether, ammonium salt, pyrrole, 2-methoxyethanol, aluminum trichloride, etc. are added It is possible. In some cases, a halogen-containing solvent such as carbon tetrachloride or ethylene trifluoride may be further added to impart nonflammability, or a carbon dioxide gas may be further added to improve high-temperature storage characteristics.

The secondary battery according to the present invention may be a lithium secondary battery, and the lithium secondary battery may be suitably used as a high output large capacity battery or a unit battery for a battery pack. The battery pack is particularly suitable for an electric vehicle , A hybrid electric vehicle, a power tool plug-in hybrid electric vehicle, a power storage device, and the like.

As described above, the negative electrode according to the present invention has a structure in which a gel polymer containing a lithium salt formed by a photopolymerization reaction is coated on a negative electrode mixture layer in a state where predetermined monomers include a lithium salt, The battery can be prevented from being short-circuited by overcharging, so that safety can be ensured, and as a result, the output and lifetime characteristics of the battery can be improved.

1 is a schematic plan view of a cathode manufacturing apparatus according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. However, the present invention is not intended to be limited by the scope of the present invention.

For the sake of understanding of the present invention, only a part of the construction of the cathode manufacturing apparatus is shown, and the detailed construction of the other cathode manufacturing apparatuses is omitted.

1 is a schematic plan view of a negative electrode manufacturing apparatus according to the present invention.

1, the apparatus for manufacturing a negative electrode according to the present invention comprises a rotating roll 110 for moving a negative electrode sheet 111 coated with a negative electrode mixture composed of a negative electrode active material, a binder and a conductive material on one surface of a current collector, , A monomer solution inlet 120 for applying a monomer solution onto the coating layer of the negative electrode mixture, a light-emitter 130 for light irradiation to cause photopolymerization of the monomer solution, and a gel polymer containing a lithium salt formed by photopolymerization And drying units 150 for drying the coated negative electrode sheet.

Specifically, the negative electrode sheet 111, on which the negative electrode mixture composed of the negative electrode active material, the binder and the conductive material is applied on the current collector, is supplied to the rotating roll 110 through the supply portion (not shown) have. The monomer aqueous solution containing the lithium salt introduced into the device through the monomer solution input portion 120 may be applied to the negative electrode mixture in the portion A and then the photopolymerization reaction may occur through light irradiation of the light-directing portion 130. After the photopolymerization reaction, the negative electrode sheet 111 passes through the drying units 150 and moves toward the discharge port 112. In the drying units 150, the negative electrode sheet 111 remains on the negative electrode sheet 111 after heat- Solvents and the like can be removed.

It is a matter of course that the moving speed of the negative electrode sheet 111 can be appropriately adjusted according to the content of the aqueous monomer solution containing the lithium salt, the intensity of ultraviolet rays used for light irradiation, and the like.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (15)

A negative electrode material mixture comprising a negative electrode active material, a binder and a conductive material is applied on a current collector, and a gel polymer containing a lithium salt is applied on the negative electrode material mixture layer, Wherein one or more monomers selected from the group consisting of a carboxylate monomer, a carboxylate monomer, a carboxylate monomer, a vinylate monomer, a (meth) acrylate monomer, and a nitrile monomer are formed by a photopolymerization reaction in the presence of a lithium salt. The negative electrode according to claim 1, wherein the content of the lithium salt is 1% by weight to 30% by weight based on the total weight of the gel polymer. The method of claim 1, wherein the lithium salt is _{LiCl, LiBr, LiI, LiClO 4} , LiBF 4, LiB 10 Cl 10, LiPF 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF 6, LiSbF 6, LiAlCl 4, CH ₃ SO ₃ Li, (CF ₃ SO ₂ ) ₂ NLi, chloroborane lithium, lithium lower aliphatic carboxylate, and lithium tetraphenylborate. The gel polymer according to claim 1, wherein the gel polymer comprises at least one monomer selected from the group consisting of an acrylate monomer, a (meth) acrylate monomer, and a nitrile monomer, which is formed by a photopolymerization reaction in the state that a lithium salt is contained And a cathode. 5. The thermoplastic resin composition according to claim 4, wherein the monomers comprise 5 to 40% by weight of an acrylate monomer, 10 to 50% by weight of a (meth) acrylate monomer, and 20 to 50% by weight of a nitrile monomer, Characterized in that the cathode A method of manufacturing a negative electrode according to claim 1,
(A) applying a negative electrode mixture composed of a negative electrode active material, a binder and a conductive material onto a current collector;
(B) applying a monomer solution containing a lithium salt onto the negative electrode mixture layer in the step (A); And
(C) photopolymerizing the monomer solution of the step (B) to prepare a gel polymer containing a lithium salt;
Wherein the negative electrode is made of a metal. [7] The method of claim 6, wherein the monomer solution comprises 1 to 20% by weight of a photopolymerization initiator based on the total weight of the monomer solution. 8. The photopolymerization initiator according to claim 7, wherein the photopolymerization initiator is at least one selected from the group consisting of benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamino) benzophenone, Phenol, 4-benzoyl-4-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy- Propylphenone, propylphenone, pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyldimethylketanol, At least one selected from the group consisting of ethoxyethyl acetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butyl anthraquinone, 2-amylanthraquinone, By weight. The method of manufacturing a cathode according to claim 6, wherein the photopolymerization is performed by irradiating ultraviolet rays. [7] The method of claim 6, further comprising a step of drying after the photopolymerization of the step (C). The cathode manufacturing apparatus according to claim 10, wherein the drying is performed using heat or wind of 100 to 300 degrees. An apparatus for producing a negative electrode according to claim 1,
(a) a rotating roll for moving a negative electrode sheet coated with a negative electrode mixture composed of a negative electrode active material, a binder and a conductive material on one surface or both surfaces of the current collector;
(b) a monomer solution injecting portion for applying the monomer solution onto the coating layer of the negative electrode mixture;
(c) a light-directing section for irradiating light to cause photopolymerization of the monomer solution; And
(d) a drying unit for drying a negative electrode sheet to which a gel polymer containing a lithium salt formed by photopolymerization is applied;
And a negative electrode. 13. The apparatus for manufacturing a negative electrode according to claim 12, wherein a moving speed of the current collector is 5 to 100 cm / sec. A secondary battery comprising a negative electrode according to claim 1 15. The secondary battery according to claim 14, wherein the battery is a lithium secondary battery.

Images