JP2010218849A - Anode for lithium-ion secondary battery, lithium-ion secondary battery using it, collector used for anode of lithium-ion secondary battery, and manufacturing method of anode for lithium-ion secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anode for a lithium-ion secondary battery realizing high capacity and long life. <P>SOLUTION: The anode for the lithium-ion secondary battery has an anode active material layer and lattice-like barrier ribs made of a conductive substance on a metal foil, the anode active material layer contains an anode active material and a conductive auxiliary combined by a binder, and is surrounded by the above barrier ribs. A height of the barrier rib is ≥6 μm, and a width of an opening of the rib is 10 to 100 μm. Further, a unit lattice of the barrier ribs takes on either a polygonal shape of a tetragon or hexagon, or a circular form. As the anode active material, silicon or the like is used. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a negative electrode for a lithium ion secondary battery, and more particularly to a negative electrode for a lithium ion secondary battery having a high capacity and a long life.

  Conventionally, lithium ion secondary batteries using graphite as a negative electrode active material have been put into practical use. Also, a negative electrode is formed by kneading a negative electrode active material, a conductive aid such as carbon black, and a resin binder to form a slurry, and applying and drying on a copper foil. Yes.

  On the other hand, with the aim of increasing the capacity, negative electrodes for lithium ion secondary batteries using metals, particularly silicon alloys, as negative electrode active materials have been developed. Since silicon alloyed by occlusion of lithium ions expands to about 4 times that of silicon before occlusion, a negative electrode using a silicon-based alloy as a negative electrode active material repeats expansion and contraction during a charge / discharge cycle.

  Therefore, a negative electrode for a non-aqueous electrolyte secondary battery that grows carbon nanofibers on the surface of a silicon-based active material, relieves strain due to expansion and contraction of the negative electrode active material particles by its elastic action, and improves cycle characteristics. It is disclosed (see, for example, Patent Document 1).

JP 2006-244984 A

  However, a conventional negative electrode that forms a negative electrode by applying and drying a slurry of a negative electrode active material, a conductive additive, and a binder, binds the negative electrode active material and the current collector with a resin binder. The bonding strength of the resin is weak. As a result, cracks occur in the negative electrode during charge / discharge, resulting in poor cycle characteristics due to pulverization and delamination of the negative electrode active material, reduced conductivity between the negative electrode active materials, and short life of the secondary battery. It was.

  In addition, the invention described in Patent Document 1 binds the negative electrode active material and the current collector with a resin, and the cycle characteristics cannot be sufficiently prevented from being deteriorated. In addition, the productivity was poor due to the formation process of carbon nanofibers.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to obtain a negative electrode for a lithium ion secondary battery that realizes a high capacity and a long life.

  In order to achieve the above-described object, the first invention has a negative electrode active material layer and a grid-like partition made of a conductive material on a metal foil, and the negative electrode active material layer is made of a binder. A negative electrode for a lithium ion secondary battery comprising a bonded negative electrode active material and a conductive additive, wherein at least a part of the negative electrode active material layer is surrounded by the partition.

  Here, “at least a part of the negative electrode active material layer is surrounded by the partition wall” means that the thickness of the negative electrode active material layer is lower than the height of the partition wall, and the entire negative electrode active material layer is surrounded by the partition wall. In addition to the case where the thickness of the negative electrode active material layer is higher than the height of the partition wall, the negative electrode active material layer covers the top surface of the partition wall, and a part of the negative electrode active material layer is surrounded by the partition wall included.

  Preferably, the height of the partition wall is 6 μm or more, the width of the opening of the partition wall is 10 μm to 100 μm, and the aperture ratio of the unit cell of the partition wall is 30% to 90%. The unit cell is preferably a polygonal shape such as a quadrangle or a hexagon, or a circle.

  A second invention is a lithium ion secondary battery using the negative electrode for the lithium ion secondary battery.

  3rd invention is a collector used for the negative electrode for lithium ion secondary batteries which comprises metal foil and the grid | lattice-like partition made from an electroconductive substance on the said metal foil.

  A fourth invention includes a step of providing a resist layer on a metal foil, a step of patterning the resist layer, a step of filling a conductive material between the resist layers, a step of removing the resist layer, and a negative electrode active material And a step of applying and drying a slurry containing a conductive material on a current collector having a grid-like partition made of a conductive material, and a method for producing a negative electrode for a lithium ion secondary battery.

  The fifth invention includes a step of providing a resist layer on a metal foil, a step of patterning the resist layer, a step of etching the metal foil, a step of removing the resist layer, and a slurry containing a negative electrode active material. A method of producing a negative electrode for a lithium ion secondary battery, comprising: applying and drying a current collector having a grid-like partition made of a conductive substance.

  According to the present invention, a negative electrode for a lithium ion secondary battery that achieves a high capacity and a long life can be obtained.

(A) The perspective view of the negative electrode 1 for lithium ion secondary batteries which concerns on 1st Embodiment, (b) The top view of the negative electrode 1. FIG. The figure which shows the modification of the partition which concerns on 1st Embodiment. The figure which shows the modification of the negative electrode which concerns on 1st Embodiment. The figure which shows the manufacturing method of the negative electrode 1 which concerns on 1st Embodiment. FIG. 5 is a continuation of FIG. FIG. 5 is a continuation of FIG. FIG. 5 is a continuation of FIG. FIG. 5 is a continuation of FIG. FIG. 5 is a continuation of FIG. The figure which shows the kneading machine 19. FIG. The figure which shows the coater 25. FIG. The figure which shows the other manufacturing method of the negative electrode 1 which concerns on 1st Embodiment. FIG. 8 is a continuation of FIG. FIG. 8B is a continuation of FIG. FIG. 8 is a continuation of FIG. FIG. 8 is a continuation of FIG. The figure which shows the manufacturing method of the negative electrode 37 for lithium ion secondary batteries which concerns on 2nd Embodiment. FIG. 9 is a continuation of FIG. FIG. 9B is a continuation of FIG. FIG. 9 is a continuation of FIG. FIG. 9 is a continuation of FIG. The figure which shows the modification of the negative electrode which concerns on 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Each drawing schematically shows each component, and does not represent an actual scale.
The negative electrode 1 according to the first embodiment will be described. FIG. 1 is a diagram showing a negative electrode 1. As shown in FIG. 1A, the negative electrode 1 has a grid-like partition wall 5 on a metal foil 3, and a negative electrode active material layer 7 in a region surrounded by the partition wall 5. Further, as shown in FIG. 1B, the partition walls 5 have a rectangular lattice shape, and the negative electrode active material layer 7 is formed on the surface of the metal foil 3 surrounded by the partition walls 5.

  The metal foil 3 is a foil made of at least one metal selected from the group consisting of copper, nickel, and stainless steel. Each may be used alone or may be an alloy of each. The thickness is preferably 4 μm to 35 μm, and more preferably 8 μm to 18 μm.

  The partition wall 5 is a partition wall formed on the surface of the metal foil 3 and made of a conductive material. Examples of the conductive material that forms the partition wall 5 include copper, nickel, tin, zinc, and silver. The height of the partition wall 5 is 6 μm or more, the width of the opening of the partition wall 5 is 10 μm to 100 μm, and the aperture ratio of the unit cell of the partition wall 5 is 30 to 90%. The unit cell is a repeating unit having a periodic structure of the partition wall 5. The aperture ratio is the ratio of the area of the region surrounded by the partition walls 5 in the unit cell, and is a value obtained by dividing the area of the negative electrode active material layer 7 by the area of the metal foil 3 in FIG. is there.

  If the height of the partition wall 5 is 6 μm or more, the thickness of the negative electrode active material layer 7 can be secured, and a high capacity can be achieved. Moreover, even if a crack occurs in the negative electrode active material layer 7 because the width of the opening of the partition wall 5 is 10 μm to 100 μm, the crack does not grow to such an extent that the negative electrode active material is separated from the current collector. Moreover, the thickness which maintains sufficient intensity | strength for the partition 5 is securable by making the aperture ratio of the unit cell of the partition 5 into 30 to 90%.

  In FIG. 1, the partition walls 5 are in square units, but the partition walls 9 are in units of hexagons as shown in FIG. 2 (a), and circles are in units as shown in FIG. 2 (b). A partition wall 11 may be used.

  The negative electrode active material layer 7 is formed by applying and drying a slurry containing a negative electrode active material, a conductive additive, and a binder. The thickness of the negative electrode active material layer 7 is 5 μm to 30 μm on one side, preferably 10 μm to 25 μm. Further, in FIG. 1, as shown in FIG. 3A, the thickness of the negative electrode active material layer 7 of the negative electrode 1 is drawn to be thinner than the height of the partition wall 5, but the negative electrode 12 shown in FIG. As described above, the negative electrode active material layer 7 may be thicker than the partition 5, and the negative electrode active material layer 7 may cover the partition 5 without exposing the partition 5 on the surface of the negative electrode 12.

  In addition, the partition wall 5 may be provided on both surfaces of the metal foil 3, and the negative electrode active material layer 7 may be formed on both surfaces. The negative electrode having the negative electrode active material layer 7 on both sides has a larger amount of the negative electrode active material per unit area than the negative electrode having the negative electrode active material layer 7 on one side, and can further increase the capacity.

  As the negative electrode active material, at least one substance selected from the group consisting of silicon, tin, antimony, aluminum, lead, and arsenic can be used. Each of these may be used alone, or an alloy or oxide of each may be used. Specifically, silicon monoxide, titanium silicide, phosphorus-doped silicon, tin iron alloy, tin cobalt alloy, antimony tin alloy, tin silver alloy, indium antimony alloy, or the like can be used.

  Moreover, a particulate negative electrode active material can be used as the negative electrode active material. In the particulate negative electrode active material, the average primary particle size is preferably 0.01 μm to 5 μm. If the average particle diameter of the particulate negative electrode active material is 0.01 μm or more, the production of the negative electrode active material is easier, and if the average particle diameter is within 5 μm, the slurry is kneaded more uniformly and homogeneously. An electrode is obtained.

  Since the fine particles are usually present in an aggregated state, the average particle size of the negative electrode active material here refers to the average particle size of the primary particles. For particle measurement, image information of an electron microscope (SEM) and a volume-based median diameter of a dynamic light scattering photometer (DLS) are used in combination. The average particle size is confirmed in advance by the SEM image, and the particle size is obtained by image analysis (for example, A image-kun manufactured by Asahi Kasei Engineering) or dispersed in a solvent to obtain DLS (for example, DLS- manufactured by Otsuka Electronics). 8000). If the fine particles are sufficiently dispersed and not agglomerated, almost the same measurement results can be obtained with SEM and DLS. Even when the shape of the negative electrode active material is a highly developed structure such as acetylene black, here, the average particle size is defined by the primary particle size, and the average particle size is obtained by image analysis of the SEM photograph. be able to.

  Note that the surface of the negative electrode active material may be coated with a conductive material. Alternatively, the negative electrode active material coated with a conductive material may be granulated, and the negative electrode active material may be used as the granulated body. The diameter of the granulated body is preferably 0.2 μm to 10 μm. Examples of the conductive material that covers the surface of the negative electrode active material include carbon, copper, tin, zinc, nickel, silver, and alloys thereof.

  The negative electrode active material can be coated with a conductive material by a CVD method, a liquid phase method, or a baking method. Moreover, it can also coat | cover by the mechanical alloying method using a ball mill etc. According to these methods, the conductive material can be coated on at least a part of the surface of the particles of the negative electrode active material.

  For granulation production, dry and wet general granulation methods can be used.For example, dry type is a mechanical alloying method in which compression and shear force are applied, and powders collide at high speed in an air current. There is a hybridization method. Furthermore, in the wet process, an electroless plating method or a spray drying method can be used alone or in combination. For example, a negative electrode active material is coated with a carbon-based conductive material in a dry manner to form a composite, and further, a conductive material or a binder is dispersed in water to form a suspension to a predetermined size by a spray dry method. There is a method of granulation. In addition, there is a method in which a negative electrode active material is dispersed in a copper sulfate solution and then copper is deposited on the surface of the negative electrode active material using a reducing agent such as sodium borohydride to form a conductive material coating. There is also a method in which after the negative electrode active material is dispersed in a polyvinyl alcohol aqueous solution (PVA aqueous solution), PVA is fired in an inert atmosphere and coated with carbon.

  The conductive assistant is a powder made of at least one conductive material selected from the group consisting of carbon, copper, tin, zinc, nickel, and silver. A single powder of carbon, copper, tin, zinc, nickel, or silver may be used, or a powder of each alloy may be used. For example, general carbon black such as furnace black and acetylene black can be used. In addition, the conductive assistant may be nanowires of these conductive substances, and carbon fibers, carbon nanotubes, copper nanowires, nickel nanowires, and the like can be used.

  As the binder, a resin binder can be used. As the resin binder, a fluororesin such as polyvinylidene fluoride (PVdF), styrene butadiene rubber (SBR), or a rubber-based material can be used.

  Next, the manufacturing method of the negative electrode 1 is demonstrated using FIG. As shown in FIG. 4A, a metal foil 3 is prepared. Thereafter, as shown in FIG. 4B, a resist is applied or a dry film resist (DFR) is stuck on the metal foil 3 in order to form the resist layer 13. The resist layer 13 is a general resist that can be patterned by exposure or the like, and may be a negative type or a positive type. The resist layer 13 is applied so as to be thicker than the height of the partition wall 5.

  As shown in FIG. 4C, the resist layer 13 is patterned using a photolithography method or the like to obtain a resist layer 15. For example, when a positive resist is used for the resist layer 13, the portion to be removed is exposed and dissolved in a solvent. Moreover, when using a negative resist for the resist layer 13, the part used as the resist layer 15 is exposed, and the part which was not exposed is melt | dissolved in a solvent. The resist layer 15 has a pattern similar to the pattern that the negative electrode active material layer 7 will form in the future.

  Thereafter, as shown in FIG. 4D, the space between the resist layers 15 on the metal foil 3 is filled with a conductive material by pattern plating, and the partition walls 5 are formed. Alternatively, the partition walls 5 are formed by applying and sintering a conductive metal paste. For example, copper plating, copper fine particle paste sintering, nickel plating, nickel fine particle paste sintering, silver plating, and silver fine particle paste sintering can be used for filling the conductive material.

  Thereafter, as shown in FIG. 4 (e), the resist layer 15 is removed to obtain a current collector 17 having a partition wall 5 on the metal foil 3.

  Thereafter, as shown in FIG. 4 (f), a slurry containing a negative electrode active material and a conductive additive is applied to the surface of the current collector 17 and dried to form the negative electrode active material layer 7.

  The application / drying of the slurry in FIG. 4 (f) is performed as follows. As shown in FIG. 5, the slurry raw material 23 is added to the kneader 19 and kneaded to form the slurry 21. The slurry raw material 23 is a negative electrode active material, a conductive additive, a binder, a thickener, a solvent, and the like.

  In the solid content in the slurry 21, the negative electrode active material contains 25 to 90% by weight, the conductive auxiliary agent contains 5 to 70% by weight, and the binder contains 1 to 10% by weight. For example, the negative electrode active material 5 is 60% by weight, the conductive additive 7 is 33% by weight, the binder 9 is 2% by weight, and the thickener is 5% by weight.

  As the kneading machine 19, a general kneading machine used for the preparation of a slurry can be used, and an apparatus capable of preparing a slurry called a kneader, a stirrer, a disperser, a mixer or the like may be used. Moreover, carboxymethylcellulose etc. can be used as a thickener. Moreover, water can be used as a solvent.

  Next, as shown in FIG. 6, the slurry 21 is coated on one side of the metal foil 3 using a coater 25 and dried. The thickness of the slurry 21 after drying is preferably 5 μm to 100 μm.

  The coater 25 can use a general coating apparatus that can apply slurry to a current collector, and is, for example, a coater using a roll coater or a doctor blade.

  Next, a method for producing a lithium ion secondary battery using the negative electrode 1 of the present invention will be described.

  First, a positive electrode active material, a conductive additive, a binder, a thickener, and a solvent are mixed to prepare a positive electrode active material composition. The composition of the positive electrode active material is directly applied on a metal current collector such as an aluminum foil and dried to prepare a positive electrode. It is also possible to manufacture a positive electrode by casting the composition of the positive electrode active material on a separate support, and then laminating the film obtained by peeling from the support on a metal current collector.

As the positive electrode active material, any lithium-containing metal oxide that is generally used can be used. For example, LiCoO ₂ , LiMn _x O _2x , LiNi _1-x Mn _x O _2x (X = 1, 2), Ni _1-xy Co _x Mn _y O ₂ (0 ≦ x ≦ 0.5, 0 ≦ y ≦ 0.5), etc., more specifically, LiMn ₂ O ₄ , LiCoO ₂ , LiNiO ₂ , LiFeO ₂ , V ₂ O ₅ , TiS, and MoS are compounds capable of oxidation and reduction of lithium.

  Carbon black is used as a conductive additive, and vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride (PVdF), polyacrylonitrile, polymethyl methacrylate, polytetrafluoroethylene (PTFE) and the like are used as a binder. A mixture and a styrene butadiene rubber-based polymer are used, and N-methylpyrrolidone (NMP), acetone, water and the like are used as a solvent. At this time, the contents of the positive electrode active material, the conductive additive, the binder, the thickener, and the solvent are at levels normally used in lithium ion secondary batteries.

  Any separator can be used as long as it has a function of insulating electronic conduction between the positive electrode and the negative electrode and is usually used in a lithium ion secondary battery. In particular, it is preferable to have a thin resistance of about 20 μm from the viewpoint of low resistance to ion migration of the electrolyte and high battery capacity. A typical separator is a three-layer laminate film of polypropylene (PP) / polyethylene (PE) / polypropylene (PP) microporous film, and PP and PE are thermoplastic resins of about 170 ° C. and about 130 ° C., respectively. The degree of polymerization and the like are designed so that the melting point becomes. When the temperature inside the battery exceeds 130 ° C., the PE film melts, the micropores are clogged and lithium ions cannot permeate, and the battery reaction can be stopped.

Examples of the electrolyte include propylene carbonate, ethylene carbonate, diethyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, butylene carbonate, benzonitrile, acetonitrile, tetrahydrofuran, 2-methyltetrahydrofuran, γ-butyrolactone, dioxolane, 4-methyloxolane, N , N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dioxane, 1,2-dimethoxyethane, sulfolane, dichloroethane, chlorobenzene, nitrobenzene, dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, methyl propyl carbonate, methyl isopropyl carbonate, ethyl propyl carbonate , dipropyl carbonate, LiPF ₆ dibutyl carbonate, in a solvent or a mixed solvent thereof and the like diethylene glycol or dimethyl ether, LiBF _4, L _{SbF 6, LiAsF 6, LiClO 4} , LiCF 3 SO 3, Li (CF 3 SO 2) 2 N, LiC 4 F 9 SO 3, LiAlO 4, LiAlCl 4, LiN (C x F 2x + 1 SO 2) (C y F _{2y + 1} SO ₂ ) (where x and y are natural numbers), one of electrolytes composed of lithium salts such as LiCl and LiI, or a mixture of two or more thereof can be dissolved and used.

  A separator is disposed between the positive electrode and the negative electrode as described above to form a battery structure. When such a battery structure is wound or folded and placed in a cylindrical battery case or a rectangular battery case, an electrolyte is injected to complete a lithium ion secondary battery.

  Further, after the battery structure is laminated in a bicell structure, it is impregnated with an organic electrolyte, and the resultant product is put in a pouch and sealed to complete a lithium ion polymer battery.

  Next, another method for manufacturing the negative electrode 1 according to the first embodiment will be described with reference to FIGS. First, as shown in FIG. 7A, a metal foil 3 is prepared. Thereafter, as shown in FIG. 7B, a patterned resist layer 27 is applied. This application is performed, for example, by forming the resist layer 27 by a screen printing method.

  Thereafter, in FIG. 7C to FIG. 7E, the partition wall 5 and the negative electrode active material layer 7 are formed by the same method as that described in FIG. 4D to FIG. 1 is formed.

  According to the first embodiment, since a silicon-based alloy is used as the negative electrode active material, the capacity can be increased as compared with the case where carbon is used as the negative electrode active material.

  Further, according to the first embodiment, since the negative electrode active material layer is surrounded by the partition walls, even if the negative electrode active material repeatedly expands and contracts during charge and discharge, and a fine crack occurs in the negative electrode, Will not propagate and grow. Therefore, the negative electrode active material is difficult to peel from the current collector, and a negative electrode for a long-life lithium ion secondary battery is obtained.

  In addition, according to the first embodiment, a vacuum system is not required, and the negative electrode can be manufactured not by batch processing but by continuous processing. Therefore, productivity is excellent.

Next, a second embodiment will be described.
FIG. 8 is a diagram illustrating a method for manufacturing the negative electrode 37 according to the second embodiment. In the following embodiment, the same number is attached | subjected to the element which fulfill | performs the same aspect as 1st Embodiment, and the overlapping description is avoided.

  As shown in FIG. 8E, the negative electrode 37 has a metal foil 29 and a partition wall 33, and the negative electrode active material layer 7 is formed in a hole 32 formed between the partition walls 33.

  The metal foil 29 can use the same material as the metal foil 3, and has a thickness of about 18 μm to 140 μm. Since the metal foil 29 must also have a thickness equivalent to that of the metal foil 3 at the location where the etched holes 32 are present, the thickness of the metal foil 29 is preferably thicker than that of the metal foil 3.

  The partition wall 33 is a portion that remains in the metal foil 29 without being etched by the resist layer 31, and is naturally the same material as the metal foil 29. The height of the partition wall 33 is equal to the depth of the hole 32 and is preferably 6 μm or more, the width of the hole 32 is 10 μm to 100 μm, and the aperture ratio of the unit cell of the partition wall 33 is 30 to 90%. Preferably there is.

  Next, the manufacturing method of the negative electrode 37 is demonstrated using FIG. As shown in FIG. 8A, a metal foil 29 is prepared. Thereafter, as shown in FIG. 8B, a resist is applied or a dry film resist (DFR) is pasted on the metal foil 29. As the resist, the same material as the resist layer 13 and the resist layer 27 can be used. The resist is patterned to obtain a resist layer 31. As a method for forming the patterned resist layer 31, the photolithography method shown in FIGS. 4B to 4C may be used, or the screen printing method shown in FIG. 7B may be used. May be. The resist layer 31 is patterned into a square, hexagon, circle, or the like.

  The resist layer 31 is formed at a location where the partition wall 33 is formed. Thereafter, as shown in FIG. 8C, the metal foil 29 is etched to form holes 32. Further, the portion remaining without being etched becomes the partition wall 33. Etching is performed by general wet etching or dry etching. When the metal foil is copper, there are ferric chloride solution, cupric chloride solution, alkali etchant and the like as an etching solution.

  Thereafter, as shown in FIG. 8D, the resist layer 31 is removed, and a current collector 35 having holes 32 and partition walls 33 in the metal foil 29 is obtained.

  Thereafter, as shown in FIG. 8 (e), a slurry containing the negative electrode active material and the conductive auxiliary is applied to the surface of the current collector 35 and dried, and the negative electrode active material and the conductive auxiliary are placed in the holes 32. The negative electrode active material layer 7 is formed by filling.

  9A, a metal foil 41 thicker than the metal foil 29 may be used to provide partition walls 33 on both sides of the current collector and fill the negative electrode active material layer 7. . The negative electrode 39 has a larger amount of negative electrode active material per unit area than the negative electrode 37, and can further increase the capacity.

  Moreover, the negative electrode active material layer 7 may cover the upper surface of the partition 33 like the negative electrode 43 shown in FIG.

  According to the second embodiment, in addition to the effect of the first embodiment, there is no step of filling the conductive material between the resist layers, so that the mass productivity is further improved.

  As mentioned above, although suitable embodiment, such as a negative electrode for lithium ion secondary batteries concerning this invention, was described, referring an accompanying drawing, this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

DESCRIPTION OF SYMBOLS 1 ......... Negative electrode 3 ......... Metal foil 5 ......... Partition wall 7 ......... Negative electrode active material layer 9, 11 ...... Partition wall 12 ......... Negative electrode 13, 15 ......... Resist layer 17 ......... Current collection Body 19 ......... Kneading machine 21 ......... Slurry 23 ......... Slurry raw material 25 ......... Coater 27 ...... Resist layer 29 ......... Metal foil 31 ......... Resist layer 32 ...... Hole 33 ... ... Bullet 35 ......... Current collector 37 ......... Negative electrode 39 ......... Negative electrode 41 ......... Metal foil 43 ......... Negative electrode

Claims (9)

On the metal foil, it has a negative electrode active material layer and a grid-like partition made of a conductive material,
The negative electrode active material layer includes a negative electrode active material bonded with a binder and a conductive additive,
A negative electrode for a lithium ion secondary battery, wherein at least a part of the negative electrode active material layer is surrounded by the partition wall.   The height of the partition wall is 6 μm or more, the width of the opening of the partition wall is 10 μm to 100 μm, and the aperture ratio of the unit cell of the partition wall is 30% to 90%. The negative electrode for lithium ion secondary batteries as described.   2. The negative electrode for a lithium ion secondary battery according to claim 1, wherein a unit cell of the partition wall is a polygonal shape such as a quadrangle or a hexagon, or a circle.   2. The lithium according to claim 1, wherein the negative electrode active material is at least one material selected from the group consisting of silicon, tin, antimony, aluminum, lead and arsenic, or a material containing an alloy thereof. Negative electrode for ion secondary battery.   The lithium ion secondary battery using the negative electrode for lithium ion secondary batteries of any one of Claims 1-4.   The collector used for the negative electrode for lithium ion secondary batteries which comprises metal foil and the grid | lattice-like partition made from an electroconductive substance on the said metal foil. Providing a resist layer on the metal foil;
Patterning the resist layer;
Filling a conductive material between the resist layers;
Removing the resist layer;
Applying and drying a slurry containing a negative electrode active material on a current collector having a grid-like partition made of a conductive material;
The manufacturing method of the negative electrode for lithium ion secondary batteries characterized by comprising. Providing a patterned resist layer on the metal foil;
Filling a conductive material between the resist layers;
Removing the resist layer;
Applying and drying a slurry containing a negative electrode active material on a current collector having a grid-like partition made of a conductive material;
The manufacturing method of the negative electrode for lithium ion secondary batteries characterized by comprising. Providing a resist layer on the metal foil;
Patterning the resist layer;
Etching the metal foil;
Removing the resist layer;
Applying and drying a slurry containing a negative electrode active material on a current collector having a grid-like partition made of a conductive material;
The manufacturing method of the negative electrode for lithium ion secondary batteries characterized by comprising.

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