Composites comprising an exfoliated graphite support material having a degree of graphitization g in an range of 50 to 93%, obtained by XRD Rietveld analysis, which is coated with ZnO nanoparticles. These composites are produced by three different methods: A) (syn) the method comprises the following consecutive steps: i) a Zn(II)salt is dissolved in a solvent ii) graphite and a base are added simultaneously iii) the mixture is stirred under impact of ultrasound iv) the solvent is removed from the suspension or B) (pre) the method comprises the following consecutive steps: i) graphite is suspended in a solvent and exfoliated via impact of ultrasound ii) a Zn(II)salt and a base are added simultaneously forming nano-ZnO particles iii) the mixture is stirred iv) the solvent is removed from the suspension or C) (post) the method comprises the following steps: i) a Zn(II)salt and a base are mixed in a solvent in a first reactor forming nano-ZnO particles ii) graphite is exfoliated via impact of ultrasound in a second reactor iii) both suspensions of i) and ii) are mixed together iv) after step iii) the solvent is removed from the suspension. These coated composites may be tempered in a further step and again coated and again tempered.

A negative active material for a rechargeable lithium battery and a rechargeable lithium battery, the negative active material including a composite including silicon particles, metal particles, and a first amorphous carbon; and a second amorphous carbon surrounding on the composite.

Provides is a cathode active material comprising particles each containing a lithium composite oxide, a coating layer containing an ammonium phosphate compound containing a metal other than lithium. The coating layer coats each of the particles. The metal other than lithium includes at least one selected from the group consisting of manganese, nickel, and cobalt.

The adhesion between metal foil serving as a current collector and a negative electrode active material is increased to enable long-term reliability. An electrode active material layer (including a negative electrode active material or a positive electrode active material) is formed over a base, a metal film is formed over the electrode active material layer by sputtering, and then the base and the electrode active material layer are separated at the interface therebetween; thus, an electrode is formed. The electrode active material particles in contact with the metal film are bonded by being covered with the metal film formed by the sputtering. The electrode active material is used for at least one of a pair of electrodes (a negative electrode or a positive electrode) in a lithium-ion secondary battery.

A nonaqueous electrolyte battery includes: a positive electrode, a negative electrode, and a nonaqueous electrolyte, wherein the positive electrode contains, as a positive electrode active material, a positive electrode material having a surface composition represented by the following formula (I); the nonaqueous electrolyte contains a halogenated carbonate represented by any of the following formulae (1) to (2) and an alkylbenzene represented by the following formula (3); a content of the halogenated carbonate is 0.1% by mass or more and not more than 50% by mass relative to the nonaqueous electrolyte; and a content of the alkylbenzene is 0.1% by mass or more and not more than 5% by mass relative to the nonaqueous electrolyte

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Electrolyte materials for use in electrochemical cells, electrochemical cells comprising the same, and methods of making such materials and cells, are generally described. In some embodiments, the materials, processes, and uses described herein relate to electrochemical cells comprising sulfur and lithium such as, for example, lithium sulfur batteries.

To improve the reliability of a power storage device. A granular active material including carbon is used, and a net-like structure is formed on part of a surface of the granular active material. In the net-like structure, a carbon atom included in the granular active material is bonded to a silicon atom or a metal atom through an oxygen atom. Formation of the net-like structure suppresses reductive decomposition of an electrolyte solution, leading to a reduction in irreversible capacity. A power storage device using the above active material has high cycle performance and high reliability.

Various embodiments of the present disclosure describe energy storage devices. In one example, an energy storage device includes an anode having a plurality of active material particles, a cathode having a transition metal oxide material, and an electrolyte including a room temperature ionic liquid to couple the anode to the cathode. Each of the plurality of anode active material particles have a particle size of between about one micrometer and about fifty micrometers. One or more of the plurality of anode active material particles are enclosed by and in contact with a membrane coating permeable to lithium ions.

The invention relates to a cathode material of lithium cobalt oxide for a lithium ion secondary battery and preparation methods and applications thereof. A cathode material comprises a core material and a coating layer, wherein the core material is Li.sub.xCo.sub.(1−y)A.sub.yO.sub.(2+z), wherein 1.0≦x≦1.11, 0≦y≦0.02, −0.2<z<0.2, and A is one or two or more selected from the group consisting of Al, Mg, Y, Zr and Ti, wherein the coating layer is Li.sub.aM.sub.bB.sub.cO.sub.d, wherein M is a lithium ion active metal element and one or two or more selected from the group consisting of Co, Ni, Mn and Mo, and B is an inactive element, and one or two or more selected from the group consisting of Al, Mg, Ti, Zr and Y, and 0.95<b+c<2.5, and the molar ratio of Li to the active metal element M is 0<a/b<1. The battery prepared by the cathode material has advantages of high capacity, high compacted density and excellent cycling stability etc., under high voltage.

Disclosed herein are a multilayer electrode and a lithium secondary battery including the same. The multilayer electrode includes an electrode current collector for transmitting electrons between an external wire and an electrode active material and three or more electrode mixture layers sequentially applied to the electrode current collector, wherein each of the electrode mixture layers includes an electrode active material and a conducting agent, and wherein the content of the conducting agent of one of adjacent electrode mixture layers that is relatively close to the current collector in the direction in which the electrode mixture layers are formed is higher than that of the conducting agent of the other of the adjacent electrode mixture layers that is relatively distant from the current collector.