A method for identifying a cell quality during cell formation includes: conducting a beginning of life cycling following an initial cell formation charge of multiple cells; collecting and preprocessing a discharge data set generated by one of the multiple cells during the beginning of life cycling; calculating a statistical variance from the discharge data set identifying an estimated probability of meeting a target cell usage time; and projecting a life span of the multiple cells.

The purpose of the present disclosure is to provide a non-aqueous electrolyte secondary battery that can suppress reductions in rapid charge cycle characteristics. The non-aqueous electrolyte secondary battery according to one embodiment of the present disclosure has a positive electrode, a negative electrode, and a non-aqueous electrolyte. The negative electrode has 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 includes graphite particles A and graphite particles B as negative electrode active materials. The internal porosity of graphite particles A is no more than 5%, and the internal porosity of graphite particles B is 8%-20%. When the negative electrode active material layer is bisected in the thickness direction, there is a greater amount of graphite particles A in the outer surface-side half than in the negative electrode collector-side half.

Provided is a negative electrode active material for a lithium secondary battery including: a silicon oxide (SiO.sub.x, 0<x≤2) composite including an alkali metal or alkaline earth metal-containing phosphate; and an aluminum-containing phosphate.

The present application relates to a battery module including a first-type battery cell and a second-type battery cell at least connected in series, where the first-type battery cell and the second-type battery cell are battery cells of different chemical systems, the first-type battery cell includes N first battery cell(s), and the second-type battery cell includes M second battery cell(s), where N and M are positive integers; and when a battery state of health (SOH) of a first battery cell is the same as an SOH of a second battery cell, and a state of charge (SOC) of the first battery cell is the same as an SOC of the second battery cell, a ratio of a total charge capacity of a first negative electrode sheet of the first battery cell to a total charge capacity of a second negative electrode sheet of the second battery cell is 0.8 to 1.2.

A nonaqueous electrolyte secondary battery includes a negative electrode mixture layer formed on a negative electrode current collector. The negative electrode mixture layer includes a first layer and a second layer. The first layer is formed on the negative electrode current collector and includes a negative electrode active material and a first binding agent. The negative electrode active material in the first layer includes a carbon material A and a Si-containing compound. The second layer is formed on the first layer and includes a negative electrode active material and a second binding agent. The negative electrode active material in the second layer includes a carbon material B. The carbon material B has a tap density higher than a tap density of the carbon material A. A packing density of the second layer is lower than a packing density of the first layer.

Described are energy storage devices employing a gas storage structure, which can accommodate or store gas evolved from the energy storage device. The energy storage device comprises an electrochemical cell with electrodes comprising metal-containing compositions, like metal oxides, metal nitrides, or metal hydrides, and a solid state electrolyte.

A lithium-sulfur battery cathode including conductive porous carbon particles vacuum infused with sulfur and a conductive collector substrate to which the sulfur infused porous carbon particles are deposited. The sulfur infused carbon particles are encapsulated by an encapsulation polymer, the encapsulation polymer having ionic conductivity, electronic conductivity, polysulfide affinity, or combinations thereof. A lithium-sulfur battery including the lithium-sulfur battery cathode, a lithium anode and an electrolyte disposed between the sulfur cathode and the lithium anode is also provided. Methods of producing the sulfur cathode for use in a lithium-sulfur battery by a hybrid vacuum-and-melt method are also provided.

An electrolyte solution additive, a non-aqueous electrolyte solution including the same, and a lithium secondary battery including the same are disclosed herein. In some embodiments, an electrolyte solution additive is represented by Formula 1

##STR00001##

wherein, in Formula 1,

R is a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

A silicon-based negative electrode material, a preparation method therefor, and an application thereof in a lithium ion battery are provided. A lithium ion battery contains the silicon-based negative electrode material. The negative electrode material contains a silicon-containing material and a phosphorus-containing coating layer at the surface of the silicon-containing material. The phosphorus-containing coating layer contains a polymer that has polycyclic aromatic hydrocarbon structural segments. The negative electrode material exhibits improved initial coulombic efficiency, reversible charging specific capacity, cycle charging capacity retention and conductivity. When used in the lithium ion battery, the negative electrode material may improve the energy density of the battery.

A secondary includes an electrode assembly having a jelly roll structure including a positive electrode sheet, a negative electrode sheet, and a separator; a cylindrical case in which the electrode assembly is received; and a flat spiral spring positioned between an outer peripheral surface of the electrode assembly and an inner surface of the cylindrical case.