A positive electrode active material particle with little deterioration is provided. A power storage device with little deterioration is provided. A highly safe power storage device is provided. The positive electrode active material particle includes a first crystal grain, a second crystal grain, and a crystal grain boundary positioned between the crystal grain and the second crystal grain; the first crystal grain and the second crystal grain include lithium, a transition metal, and oxygen; the crystal grain boundary includes magnesium and oxygen; and the positive electrode active material particle includes a region where the ratio of the atomic concentration of magnesium in the crystal grain boundary to the atomic concentration of the transition metal in first crystal grain and the second crystal grain is greater than or equal to 0.010 and less than or equal to 0.50.

A negative electrode material includes a silicon-based material, where a particle of the silicon-based material includes at least one recessed portion, and the recessed portion is 50 nm to 20 μm in width, and 50 nm to 10 μm in depth. The recessed structure leaves room for the silicon-based material to swell, thereby solving the problem of large volume swelling of the silicon-based material. In addition, when the silicon-based material with the recessed structure is composited with a carbon material, a conductive agent, and the like to form a negative electrode plate, small particles of the carbon material and the conductive agent are embedded into the recessed portion of the silicon-based material, solving the problem of low compacted density of the silicon-based negative electrode material with a recessed structure, and compensating for the low volumetric energy density of the recessed structure.

The purpose of the present invention is to provide an active material for a secondary battery electrode, the active material having excellent rate characteristics and cycle resistance. The present invention is an active material for a secondary battery electrode, the active material having an olivine-type crystal structure, while having a carbon layer on the surface, wherein the ratio of the average thickness of the carbon layer which is present on a plane that is perpendicular to the crystal b-axis to the average thickness of the carbon layer which is present on a plane that is not perpendicular to the b-axis is from 0.30 to 0.80.

An lead-acid battery is described. The battery includes a carbon fiber electrode having a paste containing a novel additive including one or more carbons, organic expanders, and barium sulfate.

There is provided a method of synthesizing a porous carbon-sulfur composite comprising the step of carbonizing a carbon material having a metal-organic framework (MOF) at a temperature of 800-1000° C. to produce a porous carbon, mixing and heating the porous carbon with sulfur to infuse the sulfur (melt diffusion) into the pores of the porous carbon and removing excess sulfur not infused into the pores or present on the surface of the porous carbon. There is also provided a cathode comprising the porous carbon-sulfur composite and a method of preparing the cathode by mixing with conductive carbon and a polymer binder. The cathode finds use in an electrochemical cell comprising a sodium or lithium anode.

The present invention is related to a manufacturing method of a negative active material for a lithium secondary battery, a negative active material for a lithium secondary battery manufactured by the method, and a lithium secondary battery including the same. According to one embodiment, it is provided that: a method of manufacturing a negative active material for lithium secondary battery, comprising: coating a negative active material precursor containing Si with crude tar or soft pitch; and annealing an obtained coating product, wherein, the crude tar contains a low molecular weight component that can be removed by a distillation process in an amount of 20 wt % or less.

Disclosed are a cathode materials suitable for an aluminium ion battery, wherein the cathode materials comprise a main group element nitride, and an oxide of a main group element or an oxide of a element in Group 1 to 13. The nitride is preferably a 2-dimensional layered material. Preferably, the ratio of the main group element nitride to the oxide is between 5:95 and 95:5 (by weight).

The disclosure relates to metal phosphorothioates, batteries comprising metal phosphorothioate, cells comprising metal phosphorothioate, and methods of making thereof.

The present disclosure relates to a positive electrode slurry for a lithium-sulfur battery including a positive electrode active material, an electrically conductive material, a binder and a solvent, where the ratio of the average particle diameter (D.sub.50) of the positive electrode active material and the positive electrode slurry is 1.5 or less, and the phase angle at 1 Hz of the positive electrode slurry is 50° or more. The positive electrode slurry for the lithium-sulfur battery of the present disclosure exhibits excellent flowability even while having a high solid content, thereby making it possible to manufacture a positive electrode for a lithium-sulfur battery with excellent electrochemical properties and improving the productivity and economic feasibility of the manufacturing process of the positive electrode for the lithium-sulfur battery.

The present disclosure belongs to the technical field of lithium battery cathode materials, and discloses a preparation method of multiple carbon-coated high-compaction lithium iron manganese phosphate, comprising the following steps: (1) synthesizing a carbon and vanadium co-doped ferromanganese phosphate precursor through a co-precipitation method, sintering, and removing crystal water to obtain an anhydrous ferromanganese phosphate precursor; (2) adding lithium phosphate, a supplemental phosphorus source, an organic carbon source, a dopant and deionized water, and performing ball milling, wet sanding, spray drying and sintering to obtain an intermediate material; and (3) adding deionized water and the organic carbon source, then performing ball milling, sanding, spray drying, sintering and air jet pulverization to obtain multiple carbon-coated high-compaction lithium iron manganese phosphate.