An electrode using a carbon nanotube as a conductive material, and excellent in resistance characteristics is provided. An electrode for a secondary battery herein disclosed has a collector, and an active material layer formed on the collector. The active material layer includes an active material and a carbon nanotube. At least a part of the surface of the carbon nanotube is coated with a material including an element with a lower electronegativity than that of carbon.

Battery electrode compositions and methods of fabrication are provided that utilize composite particles. Each of the composite particles may comprise, for example, a high-capacity active material and a porous, electrically-conductive scaffolding matrix material. The active material may store and release ions during battery operation, and may exhibit (i) a specific capacity of at least 220 mAh/g as a cathode active material or (ii) a specific capacity of at least 400 mAh/g as an anode active material. The active material may be disposed in the pores of the scaffolding matrix material. According to various designs, each composite particle may exhibit at least one material property that changes from the center to the perimeter of the scaffolding matrix material.

A positive active material for a nonaqueous electrolyte energy storage device according to one aspect of the present invention is a positive active material for a nonaqueous electrolyte energy storage device containing a lithium transition metal composite oxide having an α-NaFeO.sub.2 structure, the positive active material further containing aluminum, in which the lithium transition metal composite oxide contains at least one of nickel and cobalt, and manganese, a content of manganese in a transition metal. in the lithium transition metal composite oxide is 0.6 or less in terms of molar ratio, and in a charged state at a potential of 4.35 V vs. Li/Li.sup.+ in a state where there is no charge history in which the potential reaches 4.5 V vs. Li/Li.sup.+ or more, an oxygen positional parameter of the positive active material determined from crystal structure analysis by a Rietveld method when a space group R3-m is used. for a crystal structure model based on an X-ray diffraction pattern is 0.265 or more and 0.269 or less.

A composite particulate for a lithium battery, wherein said composite particulate has a diameter from 10 nm to 50 μm and comprises one or more than one anode active material particles that are dispersed in a high-elasticity polymer matrix or encapsulated by a high-elasticity polymer shell, wherein the high-elasticity polymer matrix or shell has a recoverable elastic tensile strain no less than 5%, when measured without an additive or reinforcement dispersed therein, and a lithium ion conductivity no less than 10.sup.−6 S/cm at room temperature and wherein the high-elasticity polymer comprises a crosslinked polymer network of chains selected from the group consisting of Poly(ethylene glycol) dimethacrylate, Poly(ethylene glycol) diacrylate, Poly (ethylene glycol)methyl ether acrylate, Polyethylene glycol diglycidyl ether (PEGDE), Poly(propylene glycol) dimethacrylate, Poly(propylene glycol) diacrylate, chemically substituted versions thereof, derivatives thereof, and combinations thereof.

The present application is generally directed to composites comprising a hard carbon material and an electrochemical modifier. The composite materials find utility in any number of electrical devices, for example, in lithium ion batteries. Methods for making the disclosed composite materials are also disclosed.

Electrolytes and electrolyte additives for energy storage devices comprising linear carbonate compounds.

An electrochemical element includes a current collector, and an active material layer supported on the current collector, wherein the active material layer includes active material particles, the active material particles each include lithium silicate composite particles each including a lithium silicate phase and silicon particles dispersed in the lithium silicate phase, and a first coating that covers at least a portion of a surface of the lithium silicate composite particles, the first coating includes an oxide of a first element other than a non-metal element, the active material layer has a thickness TA, and T1b > T1t is satisfied, where T1b is a thickness of the first coating that covers the lithium silicate composite particles at a position of 0.25TA from the surface of the current collector in the active material layer, and T1t is a thickness of the first coating that covers the lithium silicate composite particles at a position of 0.75TA from the surface of the current collector in the active material layer.

A negative electrode active material for a secondary battery includes a silicon-containing material. The silicon-containing material includes a lithium-ion conductive phase, silicon particles dispersed in the lithium-ion conductive phase, and particles containing vanadium dispersed in the lithium-ion conductive phase.

Provided are composite particles for an all-solid-state secondary battery electrode with which it is possible to form an electrode for an all-solid-state secondary battery that can cause an all-solid-state secondary battery to display excellent output characteristics, and a method of producing these composite particles. The composite particles for an all-solid-state secondary battery electrode contain an electrode active material, a binder, and an inorganic solid electrolyte that is distributed more in an outer part than in an inner part, and have a volume-average particle diameter of not less than 5 μm and not more than 90 μm. The method of producing the composite particles for an all-solid-state secondary battery electrode includes granulating a slurry composition containing an electrode active material and a binder to obtain base particles and externally adding an inorganic solid electrolyte to the base particles.

An electrode comprises carbon nanoparticles and at least one of metal particles, metal oxide particles, metalloid particles and/or metalloid oxide particles. A surfactant attaches the carbon nanoparticles and the metal particles, metal oxide particles, metalloid particles and/or metalloid oxide particles to form an electrode composition. A binder binds the electrode composition such that it can be formed into a film or membrane. The electrode has a specific capacity of at least 450 mAh/g of active material when cycled at a charge/discharge rate of about 0.1 C.