Additives for energy storage devices comprising nitrogen-containing compounds are disclosed. The energy storage device comprises a first electrode and a second electrode, where 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, and an electrolyte composition. Nitrogen-containing compounds may serve as additives to the first electrode, the second electrode, and/or the electrolyte, as well as the separator.

In a metal negative electrode, a current collector includes a through-hole or a recess provided to extend from a front surface of a planar plate toward a back surface of the planar plate. A distance from a midpoint of a joining boundary to a point on a surface of the current collector is designated as a region dividing distance, the point defining a distance less than a maximum distance between the midpoint and a side or a surface of the current collector. In the current collector, a first region is a region defined by distances from the midpoint, the distances being a distance equal to the region dividing distance and distances greater than the region dividing distance, and, in the current collector, a second region is a region defined by distances from the midpoint that are less than the region dividing distance. A volume reduction ratio of the first region is greater than a volume reduction ratio of the second region, the volume reduction ratio of the first region being a ratio with respect to a volume of the first region determined assuming that the through-hole or the recess is not present, the volume reduction ratio of the second region being a ratio with respect to a volume of the second region determined assuming that the through-hole or the recess is not present.

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 relates to an electrolyte, which is provided for an alkali-sulfur battery (e.g. for a Li—S battery). The electrolyte contains a non-polar, acyclic and non-fluorinated ether, a polar aprotic organic solvent, and a conducting salt for an alkali-sulfur battery. It has been found that, when such an electrolyte is used in an alkali-sulfur battery, a high-capacity, a low overvoltage, a high cycle stability, and a high Coulomb efficiency can be achieved in the alkali-sulfur battery and, in addition, as compared with an alkali-sulfur battery which contains a fluorinated ether in the electrolyte, a considerably improved gravimetric energy density is obtained. The invention further relates to a battery comprising the electrolyte according to the invention and to uses of the electrolyte according to the invention.

The invention relates to an electrolyte, which is provided for an alkali-sulfur battery (e.g. for a Li—S battery). The electrolyte contains a non-polar, acyclic and non-fluorinated ether, a polar aprotic organic solvent, and a conducting salt for an alkali-sulfur battery. It has been found that, when such an electrolyte is used in an alkali-sulfur battery, a high-capacity, a low overvoltage, a high cycle stability, and a high Coulomb efficiency can be achieved in the alkali-sulfur battery and, in addition, as compared with an alkali-sulfur battery which contains a fluorinated ether in the electrolyte, a considerably improved gravimetric energy density is obtained. The invention further relates to a battery comprising the electrolyte according to the invention and to uses of the electrolyte according to the invention.

Electrolyte materials for use in electrochemical cells, electrochemical cells comprising the same, and methods of making such materials and cells, are generally described. In some embodiments, the materials, processes, and uses described herein relate to electrochemical cells comprising sulfur and lithium such as, for example, lithium sulfur batteries.