JP2009123380A - Anode base material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anode base material having high output voltage and high energy density, and capable of realizing excellent charge and discharge cycle characteristics, a secondary battery using the anode base material, a resist composition used for forming the anode base material, and a manufacturing method of the anode base material. <P>SOLUTION: With the anode base material 10 made by forming a metal film 13 on a support body 11 equipped with a patterned organic film 12 formed by a light imprinting method, the battery having high output voltage and high energy density, and excellent charge and discharge cycle characteristics can be provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a negative electrode substrate, a secondary battery using the negative electrode substrate, a resist composition used for forming the negative electrode substrate, and a method for producing the negative electrode substrate, and particularly excellent in charge / discharge cycle characteristics. The present invention relates to a negative electrode substrate capable of providing a battery, a secondary battery using the negative electrode substrate, a resist composition used for forming the negative electrode substrate, and a method for producing the negative electrode substrate.

  Conventionally, research and development of batteries having high output voltage and high energy density have been actively promoted. In particular, a secondary battery having a low internal resistance and a low battery capacity decrease due to charge / discharge and excellent charge / discharge cycle characteristics is required. For example, a lithium secondary battery using thin-film amorphous silicon or microcrystalline silicon as a negative electrode material (negative electrode active material) is known (see Patent Document 1). Specifically, a lithium secondary battery using a negative electrode in which a negative electrode material layer made of a silicon thin film is formed on a current collector is disclosed. For the formation of a silicon thin film, a CVD method (chemical vapor deposition method, Thin film forming methods such as chemical vapor deposition and sputtering are used.

  Here, it is considered that a material such as silicon repeats expansion / contraction as the lithium is occluded / released. In the negative electrode in which the silicon thin film is formed on the current collector, the adhesion between the current collector and the negative electrode material layer is high, and thus the current collector is frequently expanded / contracted due to the expansion / contraction of the negative electrode material. Become. For this reason, there is a possibility that irreversible deformation such as wrinkles may occur in the negative electrode material layer and the current collector along with charging and discharging. In particular, when a metal foil having a high ductility such as a copper foil is used for the current collector, the degree of deformation tends to increase. When the negative electrode is deformed, the energy density of the battery may be lowered due to an increase in volume as an electrode and non-uniform electrochemical reaction. In addition, while the expansion / contraction associated with charge / discharge is repeated, the negative electrode material may be pulverized and detached from the current collector, or in some cases may be detached as a thin film. It becomes a factor to deteriorate.

  Examples of a method for suppressing deformation of the negative electrode include a method in which a material having high mechanical strength such as tensile strength and tensile elastic modulus is used as a current collector. However, when a negative electrode material layer made of a thin film negative electrode material is formed on a current collector made of such a material, the adhesion between the negative electrode material layer and the current collector becomes insufficient, and a sufficient charge / discharge cycle Characteristics may not be obtained. For this reason, in Patent Document 1, an intermediate layer made of a material that forms an alloy with the negative electrode material is disposed between the current collector and the negative electrode material layer, and a current collector having higher mechanical strength than the intermediate layer is used. Discloses a technique for suppressing the detachment of the negative electrode material during charging and discharging and suppressing the generation of soot and the like. Specifically, a copper layer is used as the intermediate layer, and a nickel foil is used as the current collector.

  In addition to Patent Document 1, a technique for suppressing expansion of the negative electrode material when lithium is occluded by using a thin film in which copper is dissolved in silicon as the negative electrode material layer and suppressing the occlusion amount of lithium is disclosed. (See Patent Document 2). Moreover, as the negative electrode material layer, an alloy thin film composed of a metal alloying with lithium and a metal not alloying with lithium is used, and by suppressing the occlusion amount of lithium, the negative electrode material expands when lithium is occluded. The technique to suppress is disclosed (refer patent document 3). Specifically, Sn, Ge, Al, In, Mg, Si, or the like is used as a metal that is alloyed with lithium to form a solid solution or an intermetallic compound. Cu, Fe, and the like that are not alloyed with lithium are used. Ni, Co, Mo, W, Ta, Mn, and the like are used.

Further, by using a current collector in which 10 or more deformed portions having a deformation amount in the thickness direction of 5 μm to 20 μm are formed per 1 cm ² and an aperture ratio by the deformed portions is 4% or less, charging is performed. A technique for suppressing deformation of an electrode accompanying discharge is disclosed (see Patent Document 4). Furthermore, a technique is disclosed in which a lithium non-occlusion material is disposed on at least one of the surface and the inside of a thin film negative electrode material layer capable of reversibly occluding / releasing lithium (see Patent Document 5).
Japanese Patent Laid-Open No. 2002-083594 JP 2002-289177 A JP 2002-373647 A JP 2003-017069 A JP 2005-196971 A

  However, even with any of the various negative electrode materials described above, a battery having a sufficient output voltage, energy density, and charge / discharge cycle characteristics has not been obtained. Accordingly, an object of the present invention is to provide a negative electrode base material that can realize a battery having a high output voltage, a high energy density, and excellent charge / discharge cycle characteristics by a configuration different from that of the above-described conventional technology. It is providing the secondary battery using a base material, the resist composition used for formation of this negative electrode base material, and the manufacturing method of this negative electrode base material.

  As a result of intensive studies in view of the above, the present inventors have found that, according to a negative electrode substrate in which a metal film is formed on a patterned organic film formed by a photoimprint method, a high output voltage and high energy are obtained. It has been found that a battery having a high density and excellent charge / discharge cycle characteristics can be provided, and the present invention has been completed.

  That is, the present invention relates to a negative electrode substrate comprising a metal film formed on a support provided with a patterned organic film formed by a photoimprint method, and a secondary battery using this negative electrode substrate The resist composition used for forming this negative electrode base material, and also the manufacturing method of this negative electrode base material are provided.

  According to the present invention, a negative electrode substrate capable of realizing a battery having a high output voltage and a high energy density and excellent charge / discharge cycle characteristics, a secondary battery using the negative electrode substrate, and the negative electrode substrate A resist composition used for forming the material, and a method for producing the negative electrode substrate can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Negative electrode base material>
A schematic diagram of a negative electrode substrate 10 according to the present invention is shown in FIG. As shown in FIG. 1, the negative electrode substrate 10 according to the present invention includes a support 11, a patterned organic film 12, and a metal film 13. More specifically, the metal film 13 is formed on the support 11 provided with the patterned organic film 12 patterned into a predetermined shape by the optical imprint method.

<Support>
The support 11 used for the negative electrode substrate 10 according to the present invention is not particularly limited as long as it can form the patterned organic film 12 on the surface thereof. For example, a conventionally known substrate such as a substrate for electronic components is used. Specifically, a silicon wafer, a silicon wafer provided with an organic or inorganic antireflection film, a silicon wafer provided with a magnetic film, a metal substrate such as copper, chromium, iron, aluminum, or a glass substrate Etc. These supports are made of a material containing at least one element selected from copper, nickel, stainless steel, molybdenum, tungsten, titanium, and tantalum, a metal foil, a nonwoven fabric, a metal current collector having a three-dimensional structure, etc. It may serve as a current collector or may be formed on these current collectors.

<Organic film>
The patterned organic film 12 in the negative electrode substrate 10 according to the present invention is formed by molding a resist composition described later by a photoimprint method.

[Resist composition]
The resist composition used for forming the patterned organic film 12 in the negative electrode substrate 10 according to the present invention contains at least one selected from an epoxy resin, a hydroxystyrene resin, an acrylic resin, and a methacrylic resin. If it is the resist composition which becomes, it will not specifically limit.

  Examples of the resin component constituting the resist composition include bisphenol A type novolak type epoxy resins, phenol novolak type epoxy resins, cresol novolak type epoxy resins, dicyclopentadiene epoxy resins and the like, and hydroxystyrene homopolymers. Hydroxystyrene resins such as copolymers of hydroxystyrene and other styrenic monomers, copolymers of hydroxystyrene and acrylic acid or methacrylic acid or derivatives thereof, acrylic acid, methacrylic acid or derivatives thereof, or Examples thereof include acrylic resins such as these copolymers.

  The mass average molecular weight of the resin component can be appropriately adjusted within a range in which an organic film can be formed on the support. In particular, the polystyrene-reduced mass average molecular weight (Mw) by gel permeation chromatography is also determined by the type of resin. However, it is preferably 2,000 to 100,000, more preferably 3,000 to 30,000 from the viewpoint of pattern formation.

  The resist composition preferably contains an organic solvent. Such an organic solvent is not particularly limited as long as it is an organic solvent capable of dissolving the above-mentioned resin. Specifically, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, 2-heptanone; ethylene glycol, Polyhydric alcohols such as propylene glycol, diethylene glycol, ethylene glycol monoacetate, propylene glycol monoacetate, diethylene glycol monoacetate, or monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether and derivatives thereof; Cyclic ethers such as: methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, methyl pyruvate, ethyl pyruvate, methoxypropionic acid Chill, esters such as ethyl ethoxypropionate and γ- butyrolactone and the like.

  Among the above organic solvents, use at least one organic solvent selected from propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, 2-heptanone, methyl lactate, ethyl lactate, and γ-butyrolactone. Is preferred. When using these solvents, it is desirable that the total organic solvent be 50% by mass or more.

  The resist composition preferably contains a photopolymerization initiator, and as such a photopolymerization initiator, any photopolymerization initiator used in a known resist composition can be used, Specifically, halogen-containing triazine compounds, oxime sulfonate group-containing compounds, onium salts having a naphthalene ring in the cation part, bissulfonyldiazomethanes, nitrobenzyl derivatives, sulfonate esters, trifluoromethanesulfonate esters, onium Salts, benzoin tosylate, diphenyliodonium salt, triphenylsulfonium salt, phenyldiazonium salt, benzyl carbonate and the like. When mix | blending such a photoinitiator, it is preferable that the compounding quantity shall be 0.05-5 mass% in a resist composition.

  Furthermore, the resist composition may contain a crosslinking agent. Specific examples of such crosslinking agents include amino compounds such as melamine resin, urea resin, guanamine resin, glycoluril-formaldehyde resin, succinyl. Amide-formaldehyde resin, ethylene urea-formaldehyde resin and the like are used. When mix | blending such a crosslinking agent, it is preferable to mix | blend in 1-30 mass parts with respect to 100 mass parts of above-mentioned resin components.

[Patterned organic film]

  The patterned organic film 12 is formed by applying the resist composition on the support 11 using a spinner to form an organic film, and then pressing a molding material on the organic film under a predetermined condition for light irradiation. After that, the patterning organic film is obtained by separating the mold material from the organic film to obtain a patterned organic film.

  The aspect ratio of the patterned organic film 12 obtained as described above is preferably 0.1 or more. By setting the aspect ratio of the patterned organic film 12 to 0.1 or more, the surface area of the negative electrode substrate 10 can be increased, and the amount of the metal film formed by the plating process described later can be increased. And high energy density are achieved.

  The mold material is not particularly limited as long as it is a mold material generally used in the optical imprint method. Specifically, a mold material made of quartz, sapphire, or the like can be used. Alternatively, the surface of the mold material may be subjected to a mold release treatment using a mold release material such as fluorine or silicon.

  Further, the predetermined condition for forming the patterned organic film 12 is not particularly limited as long as it is a condition generally used in the optical imprinting method. Usually, the pressing condition of the molding material is 1 to 1000 N. After that, the entire surface is irradiated with light of 200 to 500 nm to cure the organic film, and then the mold material is separated from the organic film. Further, the remaining film portion of the organic film corresponding to the convex portion of the molding material may be removed by oxygen plasma etching or the like after forming the patterned organic film 12. After the patterned organic film 12 is formed, the patterned organic film may be heated to cure the pattern. Further, the surface may be cured by light irradiation (UV curing) before the heat treatment.

[Metal film]
The metal film 13 in the negative electrode substrate 10 according to the present invention is preferably formed by plating, but is not particularly limited. A conventionally known plating process is used, and there is no particular limitation as long as the metal film 13 can be formed on the patterned organic film 12 described above. Further, the metal film 13 may be composed of a plurality of layers by a multistage plating process. The step of forming the metal film 13, that is, the plating step, is preferably performed by performing an electroless nickel plating or an electroless copper plating step following the cleaning step and the catalyzing step, and further electroless tin plating. A process, or an electrolytic tin plating process.

  The plating process suitable for the present invention will be specifically described below.

[Washing process]
First, the support 11 provided with the patterned organic film 12 is immersed in a phosphoric acid solution for cleaning. As the phosphoric acid solution, sodium phosphate or the like is used. The immersion time is preferably 30 to 180 seconds, and more preferably 45 to 90 seconds.

[Catalysis process]
The support 11 that has undergone the cleaning step is immersed in a tin chloride (SnCl ₂ ) aqueous solution having a predetermined concentration for a predetermined time. The concentration of tin chloride is ^preferably from ^{0.01g / dm 3 ~0.10g / dm 3} , 0.03g / dm 3 ~0.07g / dm 3 are more preferred. Further, the immersion time is preferably 15 to 180 seconds, and more preferably 30 to 60 seconds.

Next, the support 11 immersed in a tin chloride (SnCl ₂ ) aqueous solution for a predetermined time is immersed in a palladium chloride (PdCl ₂ ) aqueous solution having a predetermined concentration for a predetermined time. The concentration of palladium chloride is ^preferably from ^{0.01g / dm 3 ~0.3g / dm 3} , 0.03g / dm 3 ~0.07g / dm 3 are more preferred. Further, the immersion time is preferably 15 to 180 seconds, and more preferably 30 to 60 seconds.

[Electroless nickel plating process]
Nickel plating is performed by immersing the support 11 that has undergone the catalyzing step in a nickel plating bath. A conventionally known nickel plating bath is used. For example, nickel sulfate 0.05M-0.20M, sodium hypophosphite 0.10M-0.30M, lead ions 0.05ppm-0.30ppm, complexing agent 0.05M-0.30M An example is a nickel plating bath. As the complexing agent, a complexing agent of carboxylic acids is preferably used. The temperature of the nickel plating bath is preferably 50 ° C to 70 ° C, and the pH is preferably 4.0 to 5.5. Sodium hydroxide and sulfuric acid are used to adjust the pH.

  In place of the electroless nickel plating, electroless copper plating may be performed. A conventionally well-known thing is used as a copper plating bath.

[Electroless copper plating process]
The support 11 that has undergone the catalyzing step is dipped in a copper plating bath to perform copper plating. A conventionally well-known thing is used as a copper plating bath. For example, 0.02 M to 0.10 M of copper sulfate, 0.10 M to 0.40 M of formalin, 1.0 ppm to 20.0 ppm of 2,2′-bipyridyl, 50.0 ppm of surfactant (polyethylene glycol, etc.) An example is a copper plating bath containing ˜500 ppm and a complexing agent of 0.20 M to 0.40 M. As the complexing agent, an ethylene-amine complexing agent is preferably used. The temperature of the copper plating bath is preferably 50 ° C to 70 ° C, and the pH is preferably 11.5 to 12.5. Moreover, it is preferable to perform stirring by air ventilation. For adjusting the pH, potassium hydroxide and sulfuric acid are used.

[Electroless tin plating process]
The metal film 13 is formed on the patterned organic film 12 by immersing the support 11 that has undergone the electroless nickel plating or electroless copper plating process in a tin plating bath and performing tin plating. A conventionally well-known thing is used as a tin plating bath. For example, 0.02M to 0.20M tin chloride, 0.02M to 0.08M reducing agent such as titanium trichloride, trisodium citrate, disodium ethylenediaminetetraacetate (EDTA-2Na), nitrilotriacetic acid (NTA) An example is a tin plating bath containing 0.10 M to 0.50 M of a complexing agent such as The temperature of the tin plating bath is preferably 45 ° C to 70 ° C, and the pH is preferably 6.5 to 8.5. Sodium carbonate or ammonia and hydrochloric acid are used to adjust the pH. The tin plating process is preferably performed in a nitrogen atmosphere.

[Electrolytic tin plating process]
In place of the electroless tin plating, electrolytic tin plating may be performed. As such a tin plating process, the patterned organic film is obtained by performing electrolytic tin plating by immersing and energizing the support 11 that has undergone the electroless nickel plating or electroless copper plating process in a tin plating bath. A metal film 13 is formed on 12. A conventionally well-known thing is used as an electrolytic tin plating bath. Examples thereof include a commercial plating solution manufactured by Reybold Co., Ltd. and a starter Kurumo tin plating bath. The temperature of the tin plating bath is preferably 10 ° C to 28 ° C, and the pH is preferably 1.0 to 1.5. The applied current density is preferably 0.5 A / dm ^{2 to} 6.0 A / dm ² .

[Secondary battery]
The said negative electrode base material 10 is used suitably as a negative electrode base material for secondary batteries, especially a negative electrode base material for lithium secondary batteries. A lithium secondary battery is a secondary battery that uses an organic solvent and a lithium salt as an electrolytic solution, and is charged and discharged by transfer of charge by movement of lithium ions (Li ⁺ ) performed between a negative electrode and a positive electrode. , It has the advantages of high output voltage and high energy density. In conventional lithium secondary batteries, carbon is usually used as the negative electrode and a transition metal oxide lithium compound is used as the positive electrode. However, in recent years, studies on negative electrode materials have been conducted in search of higher power and higher energy density. . The negative electrode material needs to be capable of forming a thin film and reversibly occluding / releasing lithium, and the negative electrode base material 10 is preferably used because it satisfies these requirements. Here, “occlusion” means reversibly encapsulating lithium, reversibly forming an alloy or solid solution with lithium, or reversibly chemically bonding with lithium.

  When the negative electrode substrate 10 is used as a negative electrode material for a lithium secondary battery, it is necessary to form the negative electrode by laminating the negative electrode substrate 10 on a current collector. However, it is not necessary if the support 11 has conductivity, and the support 11 can be a current collector. The current collector is not particularly limited as long as it has conductivity, and its material, structure, and the like are not particularly limited. A current collector used for a conventional lithium secondary battery is used. Preferably, the adhesiveness with the negative electrode substrate 10 is good. Moreover, it is preferable that it is a material which does not alloy with lithium. Specifically, a material containing at least one element selected from the group consisting of copper, nickel, stainless steel, molybdenum, tungsten, titanium, and tantalum can be given. Moreover, structures, such as metal foil, a nonwoven fabric, and the metal electrical power collector which has a three-dimensional structure, are preferable. In particular, a metal foil is preferably used, and specifically, a copper foil or the like is preferably used. The thickness of the current collector is not particularly limited.

  Generally, in a negative electrode formed by laminating a thin film negative electrode material layer on a current collector, the internal resistance can be reduced compared to a negative electrode in which a particulate negative electrode material is laminated on a current collector together with a binder or the like. . That is, according to the negative electrode formed by laminating the negative electrode substrate 10 on the current collector, a lithium secondary battery having high power generation characteristics can be obtained. However, in a negative electrode in which a thin-film negative electrode material layer is laminated on a current collector, the adhesion between the negative electrode material layer and the current collector is large, and therefore the negative electrode material layer is expanded or contracted by charge / discharge. There is a risk of deformation such as wrinkles in the current collector. In particular, when a metal foil rich in ductility such as copper foil is used for the current collector, the degree of deformation tends to be greater. For this reason, simply laminating a thin-film negative electrode material layer on the current collector may reduce the energy density of the battery or deteriorate the charge / discharge cycle characteristics.

  On the other hand, since the negative electrode substrate 10 according to the present invention has a structure in which the metal film 13 is laminated on the patterned organic film 12, the metal film 13 expands / contracts as lithium is occluded / released. The stress generated by this is alleviated by the buffering action of the patterned organic film 12. For this reason, as a result of being able to suppress the increase in the stress which arises at the time of charging / discharging, generation | occurrence | production of deformation | transformation, such as a flaw in a negative electrode base material or a collector, can be suppressed. As a result, cracking of the negative electrode substrate and peeling from the current collector can be suppressed. That is, according to the negative electrode formed by laminating the negative electrode substrate 10 on the current collector, a lithium secondary battery having a high output voltage, a high energy density, and excellent charge / discharge cycle characteristics can be obtained. .

  In addition, it is not specifically limited about structures other than a negative electrode, The structure similar to a conventionally well-known lithium secondary battery may be sufficient. Specifically, it is mainly composed of a positive electrode capable of reversibly inserting / extracting lithium and an electrolyte having lithium conductivity. The electrolyte is held by a separator as necessary, and in contact with the negative electrode and the positive electrode while being held by the separator, lithium is exchanged.

  The positive electrode is not particularly limited as long as lithium can be reversibly occluded / released, and a positive electrode generally used for a lithium secondary battery is used. Specifically, a positive electrode in which a positive electrode material layer is stacked over a current collector may be used. For example, it is formed by dispersing a positive electrode material, a conductive agent, and a binder in a dispersion solvent to form a slurry, coating the current collector, and drying. The thicknesses of the current collector and the positive electrode material layer are not particularly limited, and are arbitrarily set according to the battery design capacity and the like.

The positive electrode material is not particularly limited, and a conventionally known material such as an oxide containing lithium and a transition element is used. _{Specifically, LiCoO 2, LiNiO 2, LiMnO} 2, LiMn 2 O 4, LiCo 0.5 Ni 0.5 O 2 or the like is used. The conductive agent is not particularly limited as long as it is a material having electrical conductivity. For example, acetylene black, carbon black, graphite powder, or the like is used. The binder is not particularly limited as long as it can maintain the shape of the positive electrode material layer after forming the positive electrode, and a rubber-based binder or a resin-based binder such as a fluororesin is used.

  The separator is not particularly limited as long as it can hold an electrolyte having lithium conductivity and can maintain electrical insulation between the negative electrode and the positive electrode. For example, a porous resin thin film such as a porous polypropylene thin film or a porous polyethylene thin film, or a resin nonwoven fabric containing polyolefin or the like is used.

The electrolyte is not particularly limited as long as it has lithium conductivity. For example, a nonaqueous electrolyte solution in which an electrolyte containing lithium is dissolved in a nonaqueous solvent is used. As the electrolyte containing lithium, for example, a lithium salt such as LiPF ₆ , LiBF ₄ , LiClO ₄ , LiAsF ₆ , LiCF ₃ SO ₃ is used. Examples of the non-aqueous solvent include cyclic carbonates such as propylene carbonate, ethylene carbonate and butylene carbonate, chain carbonates such as dimethyl carbonate, methyl ethyl carbonate and diethyl carbonate, cyclic ethers such as tetrahydrofuran and 1,3-dioxolane, A chain ether such as 1,2-dimethoxyethane, 1,2-diethoxyethane, ethoxymethoxyethane, a cyclic ester such as γ-butyrolactone, a chain ester such as methyl acetate, or a mixed solvent of these nonaqueous solvents is used. It is done. The concentration of the nonaqueous electrolyte solution is not particularly limited. As the electrolyte, a polymer electrolyte, a solid electrolyte, or the like may be used.

  The lithium secondary battery using the negative electrode substrate 10 according to the present invention as a negative electrode can have various shapes such as a coin-shaped battery, a cylindrical battery, a rectangular battery, or a flat battery. Further, the capacity is not particularly limited, and it can be applied from a small battery used for precision equipment to a large battery used for a hybrid vehicle or the like.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

〔Example〕
100 parts by mass of “Epicoat 157S70 (trade name: manufactured by Japan Epoxy Resin Co., Ltd.)” which is a polyfunctional bisphenol A novolac type epoxy resin, diphenyl [4- (phenylthio) phenyl] sulfonium hexafluorophosphate and thiodi-p-phenylenebis ( 5 parts by weight of “UVI-6992 (trade name: manufactured by Dow Chemical)” which is a mixture of diphenylsulfonium) bis (hexafluorophosphate), 5 parts by weight of 1,5-dihydroxynaphthalene, and 43 parts by weight of γ-butyrolactone are mixed. Thus, a negative photoresist composition was prepared.

This resist composition was spin-coated on a silicon wafer and pre-baked at 60 ° C. for 5 minutes and at 90 ° C. for 5 minutes to form an organic film having a thickness of 30 μm. The organic film is subjected to a pressing treatment for 5 minutes under a 200 N pressing condition using a NM401 Imprinter (manufactured by Meisho Kiko Co., Ltd.), and an ultraviolet irradiation device TOSCURE252 (Harrison Toshiba Lighting Co., Ltd.) is applied to the entire surface of the substrate. The pillar-shaped patterned organic film having a diameter of 10 μm (pitch of 20 μm) was formed by irradiating an ultra-high pressure mercury lamp (manufactured) (exposure amount: 1500 mJ / cm ² ) and then separating the mold material from the organic film.

The silicon wafer on which the patterned organic film was formed was immersed in a sodium phosphate solution for 60 seconds for cleaning treatment. Subsequently, the silicon wafer that has undergone the above cleaning step is immersed in a 0.05 g / dm ³ tin chloride (SnCl ₂ ) aqueous solution for 60 seconds, and further in a 0.05 g / dm ³ palladium chloride (PdCl ₂ ) aqueous solution. The catalyzing process was performed by immersing the film in 60 seconds.

  Next, the silicon wafer that has undergone the catalyzing step is immersed in a nickel plating bath comprising 0.20M nickel sulfate, 0.30M sodium hypophosphite, 0.30ppm lead ion, and 0.30M carboxylic acid complexing agent. And nickel plating treatment was performed. The temperature of the nickel plating bath at this time was 70 ° C., and the pH was adjusted to 5.5.

  Further, the silicon wafer that has undergone the electroless nickel plating step is immersed in a tin plating bath made of 0.20M tin chloride, 0.08M reducing agent such as titanium trichloride, and 0.50M trisodium citrate. A tin plating process was performed. At this time, the temperature of the tin plating bath was 70 ° C., and the pH was adjusted to 8.5.

  Using the negative electrode substrate obtained in the above example, a non-aqueous electrolyte secondary battery was produced by the following method. The discharge capacity after 1 to 3 cycles of this battery was measured by the following method. The results are shown in Table 1 below.

The negative electrode substrate obtained in the example was used as a working electrode, LiCoO ₂ was used as a counter electrode (positive electrode), and both electrodes were opposed to each other through a separator. A nonaqueous electrolyte secondary battery was produced by a conventional method using a mixed solution (1: 1 volume ratio) of LiPF ₆ / ethylene carbonate and dimethyl carbonate as a nonaqueous electrolyte. In this non-aqueous electrolyte secondary battery, the capacity ratio between the positive electrode and the negative electrode was 1: 1.

The discharge capacity per unit volume (mAh / cm ² ) was measured as each discharge capacity after 1 to 3 cycles. The discharge capacity per unit volume was based on the volume of the negative electrode. However, the expansion of the negative electrode during charging was not considered.

  The surface area of the negative electrode base material subjected to the tin plating treatment of the example with respect to the negative electrode base material was about 190% when the plating treatment was performed in a planar shape.

  According to the negative electrode substrate according to the present invention, it is possible to realize a battery having a high output voltage and a high energy density, and having excellent charge / discharge cycle characteristics. For example, from a small battery used for a portable device or the like, Even large batteries used in hybrid vehicles can be used for various purposes regardless of capacity.

It is a schematic diagram of the negative electrode base material which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Negative electrode base material 11 Support body 12 Patterned organic film 13 Metal film

Claims (10)

  A negative electrode substrate comprising a metal film formed on a support provided with a patterned organic film formed by a photoimprint method.   The negative electrode substrate according to claim 1, wherein the patterned organic film is a patterned organic film having an aspect ratio of 0.1 or more.   The patterned organic film is a patterned organic film formed by photoimprinting a resist composition containing at least one resin component selected from an epoxy resin, a hydroxystyrene resin, an acrylic resin, and a methacrylic resin. The negative electrode substrate according to claim 1, wherein the negative electrode substrate is provided.   The negative electrode substrate according to any one of claims 1 to 3, wherein the metal film is a metal film formed by plating.   The plating process is at least one kind of plating process selected from the group consisting of an electroless copper plating process, an electroless nickel plating process, an electroless tin plating process, and an electrolytic tin plating process. 4. The negative electrode substrate according to 4.   The plating process includes a multi-step plating process including at least one plating process of electroless copper plating process and electroless nickel plating process and at least one plating process of electroless tin plating process and electrolytic tin plating process. The negative electrode substrate according to claim 4, wherein the negative electrode substrate is a treatment.   The said negative electrode base material is a negative electrode base material for secondary batteries, The negative electrode base material of any one of Claim 1 to 6 characterized by the above-mentioned.   A secondary battery comprising: the negative electrode substrate according to claim 1; an electrolyte; and a positive electrode substrate capable of inserting and extracting the electrolyte.   It is a resist composition used for formation of the patterned organic film of any one of Claim 1 to 8, Comprising: At least 1 sort (s) chosen from an epoxy resin, a hydroxy styrene resin, an acrylic resin, and a methacryl resin A resist composition comprising: A method for producing a negative electrode substrate, comprising:
(I) applying a resist composition according to claim 9 on a support and forming an organic film;
(Ii) forming a patterned organic film by pressing a mold against the organic film and subsequently photocuring the entire support;
(Iii) a plating process for forming a metal film on the patterned organic film by a plating process;
The manufacturing method of the negative electrode base material characterized by including.

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