The invention relates to a button lithium ion battery, a preparation method thereof, and a method of producing a lithium ion cell composite flat sheet, wherein the button lithium ion battery comprises a battery housing, a cell accommodated in the battery housing and an electrolyte filled in the battery housing; the cell is formed by winding a composite flat sheet in which a first separator, a positive piece, a second separator and a negative piece are sequentially stacked and hot-laminated to form an integrated structure. The cell of the button lithium ion battery is formed by winding a composite flat sheet, so that winding efficiency can be improved, and misalignment can be avoided; moreover, chances of hand contact can be reduced, the influence of dust and water vapor can be avoided, and the quality of the lithium battery can be improved to the maximum extent.

An embodiment provides a binder for a non-aqueous electrolyte rechargeable battery including a copolymer (A) and a copolymer (B), wherein the copolymer (A) includes a unit (a-1) derived from a (meth)acrylic acid-based monomer, and a unit (a-2) derived from a (meth)acrylonitrile monomer, and the copolymer (B) includes a unit (b-1) derived from an aromatic vinyl-based monomer; and a unit (b-2) derived from an ethylenic unsaturated monomer which is at least one of an unsaturated carboxylic acid alkylester monomer, a (meth)acrylic acid-based monomer, a unsaturated carboxylic acid amide monomer, or combinations thereof.

Provided are methods for solid state pretreatment of active materials (e.g., prelithiation of silicon monoxide) while forming treated negative active material structures. Also provided are the formed structures, negative electrodes comprising these structures, and electrochemical cells comprising these electrodes. In some examples, silicon monoxide structures are mixed with lithium hydroxide structures or some other lithium-containing structures. The mixture is heated in an inert environment to form treated negative active material structures. These treated structures comprise various lithium-containing components, some of which trap lithium. When an electrochemical cell, formed with these treated negative active material structures, is initially charged and additional new lithium ions are introduced into the negative electrodes (e.g., from the positive electrode), a larger portion of these new lithium ions forms reversible components (rather than irreversible components) in the negative electrode than, for example, in a conventional cell without any such treatment.

Systems and methods utilizing aqueous-based polymer binders for silicon-dominant anodes may include an electrode coating layer on a current collector, where the electrode coating layer is formed from silicon and an aqueous-based suspension-solution binder composition comprising a water soluble (aqueous-based) polymer as part of a multi-component binder composition that also contains an water insoluble polymer. The electrode coating layer may include more than 70% silicon and the anode may be in a lithium ion battery.

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.

A negative electrode active material containing a negative electrode active material particle which includes a silicon compound particle containing a silicon compound (SiO.sub.x: 0.5≤x≤1.6). The silicon compound particle has three or more peaks in a chemical shift value ranging from −40 ppm to −120 ppm but has no peak in a chemical shift value within a range of −65±3 ppm in a spectrum obtained from .sup.29Si-MAS-NMR of the silicon compound particle. This provides a negative electrode active material capable of improving cycle characteristics when it is used as a negative electrode active material for a secondary battery.

The invention provides process for producing a stable Si or Ge electrode structure comprising cycling a Si or Ge nanowire electrode until a structure of the Si nanowires form a continuous porous network of Si or Ge ligaments.

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.

Powder comprising particles comprising a matrix material and silicon-based domains dispersed in this matrix material, whereby the matrix material is carbon or a material that can be thermally decomposed to carbon, whereby either part of the silicon-based domains are present in the form of agglomerates of silicon-based domains whereby at least 98% of these agglomerates have a maximum size of 3 μm or less, or the silicon-based domains are not at all agglomerated into agglomerates.

A negative electrode active material including a silicon-containing alloy having a predetermined composition is used in an electric device. A ratio value (B/A) of a diffraction peak intensity B of a (001) plane of Sn to a diffraction peak intensity A of a (111) plane of Si is 0.3 or more and 3.7 or less in an X-ray diffraction measurement of the silicon-containing alloy using a CuKα1 ray. Here, the diffraction peak of the (111) plane of Si is present in a range of 2θ=24 to 33° and the diffraction peak of the (001) plane of Sn is present in a range of 2θ=26 to 35°.