A positive-electrode active material contains a compound that has a crystal structure belonging to a space group FM3-M and contains is represented by the composition formula (1) and an insulating compound,
Li.sub.xMe.sub.yO.sub.αF.sub.β  (1)
wherein Me denotes one or two or more elements selected from the group consisting of Mn, Co, Ni, Fe, Al, B, Ce, Si, Zr, Nb, Pr, Ti, W, Ge, Mo, Sn, Bi, Cu, Mg, Ca, Ba, Sr, Y, Zn, Ga, Er, La, Sm, Yb, V, and Cr, and the following conditions are satisfied.
1.7≤x≤2.2
0.8≤y≤1.3
1≤α≤2.5
0.5≤β≤2

This disclosure provides for Olivine-type compounds, their preparation and use in cathode materials for sodium-ion batteries. The olivine-type compounds of the invention are obtained by a direct synthesis embodying a hydrothermal method.

A porous silicon composite including: a porous silicon composite cluster comprising a porous silicon composite secondary particle and a second carbon flake on at least one surface of the porous silicon composite secondary particle; and a carbonaceous layer on the porous silicon composite cluster, the carbonaceous layer comprising amorphous carbon, wherein the porous silicon composite secondary particle comprises an aggregate of two or more silicon primary particles, the two or more silicon primary particles comprise silicon, a silicon suboxide of the formula SiO.sub.x, wherein 0<x<2 on a surface of the silicon, and a first carbon flake on at least one surface of the silicon suboxide, the silicon suboxide is in a form of a film, a matrix, or a combination thereof, and the first carbon flake and the second carbon flake are each independently present in a form of a film, particles, a matrix, or a combination thereof. Also a method of preparing the porous silicon composite, a carbon composite, an electrode, and a device, each including the porous silicon composite, and a lithium battery including the electrode.

The present disclosure relates to a negative electrode material that may be used as a negative electrode active material. The negative electrode material includes a silicon oxide material containing a metal (M)-silicate and a carbonaceous material. According to an embodiment of the present disclosure, the negative electrode material may include the silicon oxide material containing a metal (M)-silicate and the carbonaceous material mixed with each other at a predetermined ratio. The negative electrode active material according to the present disclosure comprises a composite of a carbonaceous material having a broad particle size distribution with a metal-silicate, and thus provides improved electrical conductivity and life characteristics.

An energy storage module includes: a cover member accommodating a plurality of battery cells in an internal receiving space, each of the battery cells including a vent; a top plate coupled to a top of the cover member and including a duct corresponding to the vent of at least one of the battery cells; a top cover coupled to a top of the top plate and having an exhaust area corresponding to the duct, the exhaust area having a plurality of discharge openings, the top cover including a protrusion protruding from a bottom surface of the top cover, the protrusion extending around a periphery of the exhaust area and around a distal end of the duct; and an extinguisher sheet between the top cover and the top plate, the extinguisher sheet being configured to emit a fire extinguishing agent at a reference temperature.

Electrolytes and electrolyte additives for energy storage devices comprising functional thiophene compounds are disclosed. The energy storage device comprises a first electrode and a second electrode, wherein at least one of the first electrode and the second electrode is a Si-based electrode, a separator between the first electrode and the second electrode, an electrolyte, and at least one electrolyte additive selected from a thiophene compound.

Provided is an electrode material which is suitable for use as a material for forming electrodes for use in lithium ion secondary batteries, etc. and which makes it possible to heighten the rate characteristics of batteries. The electrode material is characterized by comprising a polymer having, in a side chain, a fluoflavin skeleton such as that shown by the formula and an inorganic active material, the polymer being contained in an amount of 1 mass % or less with respect to the solid components.

##STR00001##

A nonaqueous electrolyte secondary battery according to one embodiment of the present disclosure comprises a positive electrode, a negative electrode and a nonaqueous electrolyte solution; the negative electrode comprises a negative electrode collector and a negative electrode active material layer that is provided on the negative electrode collector; the negative electrode active material layer contains, as negative electrode active materials, graphite particles A and graphite particles B; the graphite particles A have an internal void fraction of 5% or less; the graphite particles B have an internal void fraction of from 8% to 20%; if the negative electrode active material layer is halved in the thickness direction, a region on the half closer to the outer surface contains more graphite particles A than a region on the half closer to the negative electrode collector.

A negative electrode material for a secondary battery includes a matrix containing silicon oxide, a composite oxide of one or more doping elements selected from an alkali metal, an alkaline earth metal, and a post-transition metal, and silicon, or a mixture thereof; and silicon nanoparticles dispersed and embedded in the matrix.

A negative electrode for a lithium metal battery includes a metal current collector substrate. A lithium metal layer is formed on at least one surface of the metal current collector substrate. A pre-lithiation layer is formed on the lithium metal layer. The pre-lithiation layer includes a prelithiated active material.