A positive electrode active material in which a discharge capacity decrease due to charge and discharge cycles is suppressed and a secondary battery including the positive electrode active material are provided. A positive electrode active material in which a change in a crystal structure, e.g., a shift in CoO.sub.2 layers is small between a discharged state and a high-voltage charged state is provided. For example, a positive electrode active material that has a layered rock-salt crystal structure belonging to the space group R-3m in a discharged state and a crystal structure belonging to the space group P2/m in a charged state where x in Li.sub.xCoO.sub.2 is greater than 0.1 and less than or equal to 0.24 is provided. When the positive electrode active material is analyzed by powder X-ray diffraction, a diffraction pattern has at least diffraction peaks at 2θ of 19.47±0.10° and 2θ of 45.62±0.05°.

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.

A negative electrode active material including a silicon-carbon-based particle, the silicon-carbon-based particle having a SiC.sub.x matrix and boron doped in the SiC.sub.x matrix, wherein x of the SiC.sub.x matrix is 0.3 or more and less than 0.6.

A main object of the present disclosure is to provide a method for producing a slurry in which chronological aggregation of an oxide active material is restrained. The present disclosure achieves the object by providing a method for producing a slurry containing an oxide active material, a solid electrolyte, a dispersion medium, and at least one of a conductive material and a binder, the method comprising: a dispersion preparing step of preparing a dispersion containing the oxide active material, the solid electrolyte, and the dispersion medium; and an adding step of adding at least one of the conductive material and the binder to the dispersion; wherein when Hansen parameters (σH) of the oxide active material, the solid electrolyte, and the dispersion medium are respectively regarded as σHa, σHb, and σHc, relationship of σHa−σHc≥5, and relationship of σHa>σHb>σHc are satisfied.

Electrolytes and electrolyte additives for use in energy storage devices, comprising cyclic carbonate compounds.

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.

An electrode including micro-sized secondary particle (MSSP) with enhanced ionic conductivity for solid-state battery is provided. The MSSP comprises a cathode particle and a solid-state electrolyte. The cathode particle is at least partially coated by solid-state electrolyte. The lithium ion transport inside the micro-sized secondary particles is increased by the incorporation of solid-state electrolyte. The electrode can be prepared by casting the slurry comprising MSSP, another electrolyte, binders, and conductive additives on the current collector. The current collector is comprised of a conductive material. The current collector has a first side and a second side. The electrode active material layer is disposed on one of the first and second sides of the current collector.

The present invention provides a method of manufacturing of an electrostatic self-assembled Silicon/rGO/carbon nanofibers composite, the method including: (a) obtaining a Si@APTES solution by adding predetermined Si nanoparticles to the piranha solution, and stirring, filtering, washing and drying, and then, dispersing the dried Si nanoparticles in deionized water, by adding APTES, and then stirring; (b) obtaining a Si@N-doped GO dispersion by mixing a mixture with the addition of urea (CH4N2O) to the GO solution and the prepared Si@APTES in step (a) in an ethanol aqueous solution; (c) obtaining a Si@N-doped GO/CNF composite by adding a predetermined CNF to the prepared Si@N-doped GO dispersion in step (b) and stirring it; and (d) obtaining a thermally reduced Si@N-doped rGO/CNF composite through a heat treatment process to the prepared Si@N-doped GO/CNF composite in step (c).

A negative electrode active material tor a secondary battery includes a silicate composite particle including crystalline silicon particles, an amorphous phase comprising an Li element, an O element, and an Si element, and a silicon oxide phase, wherein the silicon oxide phase and the silicon particles are dispersed in the amorphous phase.

The present disclosure is directed to methods of securing battery tab structures to binderless, collectorless self-standing electrodes, comprising electrode active material and carbon nanotubes and no foil-based collector, and the resulting battery-tab secured electrodes. Such methods and the resulting battery tab-secured electrodes may facilitate the use of such composites in battery and power applications.