Abstract: A positive electrode active material includes: a complex oxide particle containing at least lithium and one or plural transition metals; and a coating layer provided in at least a part of the complex oxide particle, wherein the coating layer contains at least one element M which is different from the principal transition metal constituting the complex oxide particle and which is selected among elements belonging to the Groups 2 to 13, and at least one element X selected among phosphorus (P), silicon (Si) and germanium (Ge), and the element M and the element X show different distribution from each other in the coating layer.

Abstract: In one embodiment, an active cathode material comprises a mixture that includes: at least one of a lithium cobaltate and a lithium nickelate; and at least one of a manganate spinel represented by an empirical formula of Li(1+x1)(Mn1?y1A?y1)2?x1Oz1 and an olivine compound represented by an empirical formula of Li(1?x2)A?x2MPO4. In another embodiment, an active cathode material comprises a mixture that includes: a lithium nickelate selected from the group consisting of LiCoO2-coated LiNi0.8Co0.15Al0.05O2, and Li(Ni1/3Co1/3Mn1/3)O2; and a manganate spinel represented by an empirical formula of Li(1+x7)Mn2?y7Oz7. A lithium-ion battery and a battery pack each independently employ a cathode that includes an active cathode material as described above.

Abstract: Process for the preparation of electrodes from a porous material making it possible to obtain electrodes that are useful in electrochemical systems and that have at least one of the following properties: a high capacity in mAh/gram, a high capacity in mAh/liter, a good capacity for cycling, a low rate of self discharge, and a good environmental tolerance.

Abstract: Provided is a lithium secondary battery having improved discharge characteristics in a range of high-rate discharge while minimizing a dead volume and at the same time, having increased cell capacity via increased electrode density and electrode loading amounts, by inclusion of two or more active materials having different redox levels so as to exert superior discharge characteristics in the range of high-rate discharge via sequential action of cathode active materials in a discharge process, and preferably having different particle diameters.

Abstract: High capacity lithium-ion electrochemical cells and methods of making the same are provided that include a positive electrode that includes a lithium mixed metal oxide having a first irreversible capacity and a negative electrode that includes an alloy anode material having a first irreversible capacity when the anode is delithiated to 0.9 V vs. Li/Li+. The lithium mixed metal oxide includes at least one of nickel, cobalt, and manganese. The alloy anode compound includes at least one of silicon and tin. The first cycle irreversible capacity of the positive electrode is greater than or equal to the first cycle irreversible capacity loss of the negative electrode.

Abstract: The invention offers an electrode material that can accomplish both high capacity and high output and a battery, a nonaqueous-electrolyte battery, and a capacitor all incorporating the electrode material. The electrode material has a sheet-shaped aluminum porous body carrying an active material. The above-described aluminum porous body has a skeleton structure that is formed of an aluminum layer and that has a vacant space at the interior. When observed by performing cutting in a direction parallel to the direction of thickness of the sheet, the above-described vacant space in the skeleton structure has an average area of 500 ?m2 or more and 6,000 ?m2 or less.

Abstract: The rechargeable lithium battery includes a positive electrode which includes a positive active material, a negative electrode, and an electrolyte which includes a non-aqueous organic solvent and a lithium salt. The positive active material includes a core including at least one of a compound represented by Formula 1 and a compound represented by Formula 2, and a surface-treatment layer which is formed on the core and includes a compound represented by Formula 3. The lithium salt includes LiPF6 and a lithium imide-based compound. LiaNibCocMndMeO2??(1) LihMn2MiO4??(2) M?xPyOz??(3) wherein each of M and M? is independently selected from the group consisting of an alkali metal, an alkaline-earth metal, a Group 13 element, a Group 14 element, a transition element, a rare earth element, and combinations thereof, 0.95?a?1.1, 0?b?0.999, 0?c?0.999, 0?d?0.999, 0.001?e?0.2, 0.95?h?1.1, 0.001?i?0.2, 1?y?4, 0?y?7, and 2?z?30.

Abstract: The rechargeable lithium battery of the present invention includes a positive electrode including a positive active material, a negative electrode including a negative active material, and a non-aqueous electrolyte. The positive active material includes a core and a coating layer formed on the core. The core is made of a material such as LiCo0.98M?0.02O2, and the coating layer is made of a material such as MxPyOz. The electrolyte solution includes a nitrile-based additive. The rechargeable lithium battery of the present invention shows higher cycle-life characteristics and longer continuous charging time at high temperature.

Abstract: The specification relates to a composite particle for storing lithium. The composite particle is used in an electrochemical cell. The composite particle includes a metal oxide on the surface of the composite particle, a major dimension that is approximately less than or equal to 40 microns and a formula of MM?Z, wherein M is from the group of Si and Sn, M? is from a group of Mn, Mg, Al, Mo, Bronze, Be, Ti, Cu, Ce, Li, Fe, Ni, Zn, Co, Zr, K, and Na, and Z is from the group of O, Cl, P, C, S, H, and F.

Abstract: A cathode material for a lithium ion secondary battery includes an oxide represented by a composition formula Li2-xMIIyM(Si,MB)O4, wherein MII represents a divalent element; M represents at least one element selected from the group consisting of Fe, Mn, Co and Ni; and MB represents, as an optional component, an element substituted for Si to compensate for a difference between an electric charge of [Li2]2+ and an electric change of [Li2-xMIIy]n+ as needed. In the composition formula representing the oxide, x and y are ?0.25<x?0.25 and 0<y?0.25.

Abstract: A cathode material for a lithium ion secondary battery includes an oxide represented by a composition formula Li2+x(M,MA)(Si,MB)O4, wherein M represents at least one element selected from the group consisting of Fe, Mn, Co and Ni; MA and MB represent elements substituted for parts of M and Si, respectively, to compensate for an electric charge equivalent to x of Li+; and at least one of MA and MB is included. In the composition formula representing the oxide, 0<x?0.25.

Abstract: A positive electrode active material capable of improving an output performance of a nonaqueous electrolyte secondary battery is provided. A positive electrode active material of a nonaqueous electrolyte secondary battery 1 contains a first positive electrode active material and a second positive electrode active material. In the first positive electrode active material, the content of cobalt is 15% or more on an atomic percent basis in transition metals. In the second positive electrode active material, the content of cobalt is 5% or less on an atomic percent basis in transition metals. An average secondary particle diameter r1 of the first positive electrode active material is smaller than an average secondary particle diameter r2 of the second positive electrode active material.

Abstract: Thin-film solid state batteries architectures and methods of manufacture are provided. Architectures include solid-state batteries with one or more cathodes, electrolytes, anodes deposited onto a substrate. Architectures may be used for solid state lithium batteries. The various fabrication techniques may be used to create a solid state battery is millimeters thick or smaller. These thin-film batteries may be small, light, and have a high energy density.

Abstract: Because of the composition represented by General Formula: Li1+x+?Ni(1?x?y+?)/2Mn(1?x?y??)/2MyO2 (where 0?x?0.05, ?0.05?x+??0.05, 0?y?0.4; ?0.1???0.1 (when 0?y?0.2) or ?0.24???0.24 (when 0.2<y?0.4); and M is at least one element selected from the group consisting of Ti, Cr, Fe, Co, Cu, Zn, Al, Ge and Sn), a high-density lithium-containing complex oxide with high stability of a layered crystal structure and excellent reversibility of charging/discharging can be provided, and a high-capacity non-aqueous secondary battery excellent in durability is realized by using such an oxide for a positive electrode.

Abstract: A rechargeable lithium battery including a positive electrode including a positive active material, a negative electrode including a negative active material, and a non-aqueous electrolyte including a non-aqueous organic solvent and a lithium salt. The positive electrode has an active-mass density of about 3.7 to 4.1 g/cc, and the non-aqueous electrolyte includes a nitrile-based compound additive, a non-aqueous organic solvent, and a lithium salt.

Abstract: A method for making a composite of cobalt oxide is disclosed. An aluminum nitrate solution is provided. Lithium cobalt oxide particles are introduced into the aluminum nitrate solution. The lithium cobalt oxide particles are mixed with the aluminum nitrate solution to form a mixture. A phosphate solution is added into the mixture to react with the aluminum nitrate solution and form an aluminum phosphate layer on surfaces of the lithium cobalt oxide particles. The lithium cobalt oxide particles with the aluminum phosphate layer formed on the surfaces thereof are heat treated to form a lithium cobalt oxide composite. The lithium cobalt oxide composite is electrochemical lithium-deintercalated at a voltage of Vx, wherein 4.5V<Vx?5V to form a cobalt oxide. The present disclosure also relates to a cobalt oxide and a composite of cobalt oxide.

Abstract: A family of electrolytes for use in a lithium ion battery. The genus of electrolytes includes ketone-based solvents, such as, 2,4-dimethyl-3-pentanone; 3,3-dimethyl 2-butanone(pinacolone) and 2-butanone. These solvents can be used in combination with non-Lewis Acid salts, such as Li2[B12F12] and LiBOB.

Abstract: A lithium-ion battery having an anode including an array of nanowires electrochemically coated with a polymer electrolyte, and surrounded by a cathode matrix, forming thereby interpenetrating electrodes, wherein the diffusion length of the Li+ ions is significantly decreased, leading to faster charging/discharging, greater reversibility, and longer battery lifetime, is described. The battery design is applicable to a variety of battery materials. Methods for directly electrodepositing Cu2Sb from aqueous solutions at room temperature using citric acid as a complexing agent to form an array of nanowires for the anode, are also described. Conformal coating of poly-[Zn(4-vinyl-4?methyl-2,2?-bipyridine)3](PF6)2 by electroreductive polymerization onto films and high-aspect ratio nanowire arrays for a solid-state electrolyte is also described, as is reductive electropolymerization of a variety of vinyl monomers, such as those containing the acrylate functional group.

Abstract: An as-prepared cathode for a secondary battery, the cathode including an alkaline source material including an alkali metal oxide, an alkali metal sulfide, an alkali metal salt, or a combination of any two or more thereof.

Abstract: In an aspect, a positive active material for a rechargeable lithium battery including: a compound that reversibly intercalates and deintercalates lithium; and a coating layer coating the compound and including a metal nitrate is disclosed. Since the positive active material is structurally stable during the charge and discharge, the obtained battery may have excellent battery capacity and cycle-life characteristics and also have high power.

Abstract: A lithium metal oxide powder for use as a cathode material in a rechargeable battery, consisting of a core material and a surface layer, the core having a layered crystal structure consisting of the elements Li, a metal M and oxygen, wherein the Li content is stoichiometrically controlled, wherein the metal M has the formula M=Co1-aM?a, with 0?a?0.05, wherein M? is either one or more metals of the group consisting of Al, Ga and B; and the surface layer consisting of a mixture of the elements of the core material and inorganic N-based oxides, wherein N is either one or more metals of the group consisting of Mg, Ti, Fe, Cu, Ca, Ba, Y, Sn, Sb, Na, Zn, Zr and Si.

Abstract: A cathode of the lithium battery includes a composite film. The composite film includes a carbon nanotube film structure and a plurality of active material particles dispersed in the carbon nanotube film structure.

Abstract: Disclosed herein is a hybrid capacitor including: a first structure including a cathode containing activated carbon and an anode containing lithium; and a second structure including activated carbon layers formed on both surfaces of a current collector. With the hybrid capacitor, characteristics of an LIC and characteristics of an EDLC are implemented in a single cell, thereby making it possible to increase energy density and improve output characteristics.

Abstract: The present invention relates to a silicon-based composite including a silicon oxide which is coated thereon with carbon and bonded therein to lithium. The present invention also relates to a method of producing a silicon-based composite, comprising coating a surface of silicon oxide with carbon, mixing the silicon oxide coated with carbon with lithium oxide, and heat-treating a mixture of the silicon oxide coated with carbon and the lithium oxide in an inert atmosphere.

Abstract: A nonaqueous electrolyte battery includes a positive electrode, a negative electrode and a nonaqueous electrolyte. The negative electrode contains a lithium compound and a negative electrode current collector supporting the lithium compound. A log differential intrusion curve obtained when a pore size diameter of the negative electrode is measured by mercury porosimetry has a peak in a pore size diameter range of 0.03 to 0.2 ?m and attenuates with a decrease in pore size diameter from an apex of the peak. A specific surface area (excluding a weight of the negative electrode current collector) of pores of the negative electrode found by mercury porosimetry is 6 to 100 m2/g. A ratio of a volume of pores having a pore size diameter of 0.05 ?m or less to a total pore volume is 20% or more.

Abstract: A lithium-ion battery includes a positive electrode having a first active material and a second active material and a negative electrode including a third active material. The second active material includes a lithiated form of a material that does not include electrochemically cyclable lithium in the as-provided state.

Abstract: The present disclosure provides an embodiment of an integrated structure that includes a first electrode of a first conductive material embedded in a first semiconductor substrate; a second electrode of a second conductive material embedded in a second semiconductor substrate; and a electrolyte disposed between the first and second electrodes. The first and second semiconductor substrates are bonded together through bonding pads such that the first and second electrodes are enclosed between the first and second semiconductor substrates. The second conductive material is different from the first conductive material.

Abstract: A secondary battery electrode, which is formed by stacking an electrode active material layer (I) containing spinel-structured lithium manganate as an electrode active material and an electrode active material layer (II) containing, as an electrode active material, a composite oxide represented by the following Chemical formula (1) in a thickness direction of the electrode, in which the electrode active material layer (I) is disposed in contact with a current collector, and an average particle diameter of the composite oxide is smaller than an average particle diameter of the spinel-structured lithium manganate. In such a way, it is possible to provide a secondary battery electrode capable of realizing a secondary battery excellent in both of a volumetric energy density and a volumetric output density.

Abstract: A conventional, multilayer, all-solid-state, lithium ion secondary battery where an electrode layer and an electrolyte layer are stacked has a problem that it has a high interface resistance between the electrode layer and the electrolyte layer and has a difficulty in increasing the capacity of the battery. A battery has been manufactured by applying pastes of a mixture of an active material and a solid electrolyte to form electrode layers and baking a laminate of electrode layers and electrolyte layers at a time. As a result, a matrix structure including the active material and the solid electrolyte has been formed in the electrode layers, so that a battery with a large capacity and a reduced interface resistance between the electrode layer and the electrolyte layer has been successfully achieved.

Abstract: A cathode active material including a lithium metal oxide composite having a first domain and a second domain and represented by Formula 1: x[Li2-y(M1)1-z(M2)y+zO3]-(1?x)[LiMeO2]??Formula 1 wherein 0<x<1, 0?y<1, 0?z<1, 0<y+z<1, M1 includes at least one transition metal, M2 includes at least one metal selected from magnesium (Mg), aluminum (Al), vanadium (V), zinc (Zn), molybdenum (Mo), niobium (Nb), lanthanum (La), and ruthenium (Ru), and Me includes at least one metal selected from nickel (Ni), cobalt (Co), manganese (Mn), iron (Fe), chromium (Cr), titanium (Ti), copper (Cu), aluminum (Al), magnesium (Mg), zirconium (Zr), and boron (B).

Abstract: In an aspect, a positive active material composition for a rechargeable lithium battery including a positive active material coated with a vanadium pentaoxide (V2O5) and an aqueous binder, a positive electrode including the same, and a rechargeable lithium battery including the positive electrode is disclosed.

Abstract: A lithium secondary battery includes an electrode assembly having a positive electrode (1), a negative electrode (2) having a negative electrode current collector and a negative electrode active material layer formed on a surface of the negative electrode current collector and composed of a binder and negative electrode active material particles containing silicon and/or a silicon alloy, and a separator (3) interposed between the electrodes. The electrode assembly is impregnated with a non-aqueous electrolyte. The binder contains a polyimide resin represented by the following chemical formula (1): where R contains at least a benzene ring, and n is within the range of from 10 to 100,000, and the negative electrode active material particles have an average particle size of 5 ?m or greater.

Abstract: A battery has an anode, a separator adjacent the anode, and a cathode adjacent the separator opposite the anode, the cathode comprising interdigitated stripes of materials, one of the materials forming a pore channel.

Abstract: A protected active metal electrode and a device with the electrode are provided. The protected active metal electrode includes an active metal substrate and a protection layer on a surface of the active metal substrate. The protection layer at least includes a metal thin film covering the surface of the active metal substrate and an electrically-conductive thin film covering a surface of the metal thin film. A material of the metal thin film is Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, or W. A material of the electrically-conductive thin film is selected from nitride of a metal in the metal thin film, carbide of a metal in the metal thin film, a diamond-like carbon (DLC), and a combination thereof.

Abstract: Improved cycling of high voltage lithium ion batteries is accomplished through the use of a formation step that seems to form a more stable structure for subsequent cycling and through the improved management of the charge-discharge cycling. In particular, the formation charge for the battery can be performed at a lower voltage prior to full activation of the battery through a charge to the specified operational voltage of the battery. With respect to management of the charging and discharging of the battery, it has been discovered that for the lithium rich high voltage compositions of interest that a deeper discharge can preserve the cycling capacity at a greater number of cycles. Battery management can be designed to exploit the improved cycling capacity obtained with deeper discharges of the battery.

Abstract: According to one embodiment, a non-aqueous electrolyte battery includes an outer case, a negative electrode, a positive electrode including a current collector and a positive electrode layer formed on surface of the current collector and opposed to the negative electrode layer, and a non-aqueous electrolyte, wherein the positive electrode layer includes a layered lithium nickel cobalt manganese composite oxide and a lithium cobalt composite oxide, the positive electrode layer has a pore volume with a pore diameter of 0.01 to 1.0 ?m, the pore volume being 0.06 to 0.25 mL per 1 g of a weight of the positive electrode layer, and a pore surface area within the pore volume range is 2.4 to 8 m2/g.

Abstract: Disclosed is a device for producing an electric current and a method for making the same. The device for producing an electric current, comprising: an anode comprising a stack formed by alternately stacking of at least one Si layer and at least one carbon material layer, and a LiPON layer on the stack; a cathode; and an electrolyte between the anode and the cathode.

Abstract: This invention provides a positive electrode material having high capacity and safety, and a lithium ion secondary battery using the positive electrode material, the lithium ion secondary battery using a positive electrode active substance comprising a first transition metal oxide represented by the compositional formula: Lix1Nia1Mnb1Coc1Md1O2; a second transition metal oxide represented by the compositional formula: Lix2Nia2Mnb2Coc2Md2O2; and a third transition metal oxide represented by the compositional formula: Lix3Nia3Mnb3Coc3Md3O2; in which a3<a2<a1.

Abstract: Provided is a cathode active material including a lithium metal oxide of Formula 1 below: Li[LixMeyMz]O2+d??<Formula 1> wherein x+y+z=1; 0<x<0.33; 0<z<0.1; 0?d?0.1; Me is at least one metal selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Mg, Zr, and B; and M is at least one metal selected from the group consisting of Mo, W, Ir, Ni, and Mg.

Abstract: Disclosed is a secondary battery including a cathode, an anode, a membrane and an electrolyte, wherein the cathode contains a mixture of a first cathode material defined herein and a second cathode material selected from the group consisting of a second-(a) cathode material defined herein and a second-(b) cathode material defined herein, and a combination thereof, wherein a mix ratio of the two cathode materials (first cathode material:second cathode material) is 50:50 to 90:10, and the membrane is an organic/inorganic composite porous membrane including (a) a polyolefin-based membrane substrate and (b) an active layer in which one or more areas selected from the group consisting of the surface of the substrate and a portion of pores of the substrate are coated with a mixture of inorganic particles and a binder polymer, wherein the active layer has a structure in which the inorganic particles are interconnected and fixed through a binder polymer and porous structures are formed by the interstitial volume betw

Abstract: Some embodiments of the present invention provide a system that adaptively charges a battery, wherein the battery is a lithium-ion battery which includes a transport-limiting electrode governed by diffusion, an electrolyte separator and a non-transport-limiting electrode. During operation, the system determines a lithium surface concentration at an interface between the transport-limiting electrode and the electrolyte separator based on a diffusion time for lithium in the transport-limiting electrode. Next, the system calculates a charging current or a charging voltage for the battery based on the determined lithium surface concentration. Finally, the system applies the charging current or the charging voltage to the battery.

Abstract: A cathode active material capable of increasing a capacity and improving high temperature characteristics or cycle characteristics, a method of manufacturing it, a cathode using the cathode active material, and a battery using the cathode active material are provided. In a cathode active material contained in a cathode, a coating layer is provided on at least part of complex oxide particle containing at least lithium (Li) and cobalt (Co). The coating layer is an oxide which contains lithium (Li) and at least one of nickel (Ni) and manganese (Mn).

Abstract: Lithium rich and manganese rich lithium metal oxides are described that provide for excellent performance in lithium-based batteries. The specific compositions can be engineered within a specified range of compositions to provide desired performance characteristics. Selected compositions can provide high values of specific capacity with a reasonably high average voltage. Compositions of particular interest can be represented by the formula, x Li2MnO3.(1?x) Li Niu+?Mnu??CowAyO2. The compositions undergo significant first cycle irreversible changes, but the compositions cycle stably after the first cycle.

Abstract: In a non-aqueous electrolyte secondary battery including a positive electrode 1, a negative electrode 2 and a non-aqueous electrolyte, a positive electrode active material wherein a particle of at least one compound selected from Er hydroxide, Er oxyhydroxide, Yb hydroxide, Yb oxyhydroxide, Tb hydroxide, Tb oxyhydroxide, Dy hydroxide, Dy oxyhydroxide, Ho hydroxide, Ho oxyhydroxide, Tm hydroxide, Tm oxyhydroxide, Lu hydroxide, and Lu oxyhydroxide is dispersed and adhered on a surface of a positive electrode active material particle containing Li is used.

Abstract: Positive electrode active materials comprising a dopant in an amount of 0.1 to 10 mole percent of Mg, Ca, Sr, Ba, Zn, Cd or a combination thereof are described that have high specific discharge capacity upon cycling at room temperature and at a moderate discharge rate. Some materials of interest have the formula Li1+xNi?Mn?-?Co?A?X?O2?zFz, where x ranges from about 0.01 to about 0.3, ? ranges from about 0.001 to about 0.15, and the sum x+?+?+?+?+? can approximately equal 1.0. The materials can be coated with a metal fluoride to improve the performance of the materials especially upon cycling. The materials generally can have a tap density of at least 1.8 g/mL. Also, the materials can have an average discharge voltage of around 3.6 V.

Abstract: Provided is spinel-type lithium transition metal oxide (LMO) used as a positive electrode active material for lithium battery, said LMO being capable of simultaneously achieving all output characteristics (rate characteristics), high temperature cycle life characteristics, and rapid charging characteristics. The disclosed is spinel-type lithium transition metal oxide including, besides Li and Mn, one or more elements selected from a group consisting of Mg, Ti, Ni, Co, and Fe, and having crystallite size of between 200 nm and 1000 nm and strain of 0.0900 or less. Because the crystallite size is markedly large, oxygen deficiency is markedly little, and the structure is strong, when the LMO is used as a positive electrode active material for lithium secondary batteries, all output characteristics (rate characteristics), high temperature cycle life characteristics, and rapid charging characteristics can be achieved simultaneously.

Abstract: Hybrid solid-liquid electrolyte lithium-ion battery devices are disclosed. Certain devices comprise anodes and cathodes conformally coated with an electron insulating and lithium ion conductive solid electrolyte layer.

Abstract: A cathode active material including a lithium metal oxide represented by Formula 1 below: Li[LixMeyM?z]O2+d??Formula 1 wherein x+y+z=1, 0<x<0.33, 0.05?z?0.15, 0?d?0.1, Me includes at least one metal selected from the group consisting of manganese (Mn), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), aluminum (Al), and boron (B), and M? includes at least one metal selected from the group consisting of germanium (Ge), ruthenium (Ru), tin (Sn), titanium (Ti), niobium (Nb), and platinum (Pt).

Abstract: In one aspect, an electrode assembly comprising a positive electrode, a negative electrode and a separator, wherein the positive electrode further comprises a first positive electrode active material layer, and a second positive electrode active material layer formed on one surface of the first positive electrode active material layer, the first positive electrode active material layer further comprises a first positive electrode active material containing manganese (Mn), and the second positive electrode active material layer further comprises a second positive electrode active material containing cobalt (Co) and a lithium battery comprising the same are provided.

Abstract: An anode and a battery, which have a high capacity and can improve battery characteristics such as large current discharge characteristics and low temperature discharge characteristics are provided. An anode has an anode current collector and an anode active material layer provided on the anode current collector. The density of the anode active material layer is in the range from 1.5 g/cm3 to 1.8 g/cm3. Further, the anode active material layer contains a granulated graphite material which is obtained by granulating a flat graphite particle in nodular shape and mesocarbon microbeads. Thereby, the granulated graphite material is prevented from being destroyed, and diffusion path of lithium ions is secured.