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.

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.

The invention relates to the technical field of secondary batteries, specifically to a high-temperature lithium secondary battery electrolyte and a battery cell. The high-temperature lithium secondary battery contains an additive composition consisting of a diisocyanate compound and a bicyclic sulfate compound.

The invention relates to the technical field of secondary batteries, specifically to a high-temperature lithium secondary battery electrolyte and a battery cell. The high-temperature lithium secondary battery contains an additive composition consisting of a diisocyanate compound and a bicyclic sulfate compound.

This invention provides nonaqueous electrolyte solutions for lithium batteries. The nonaqueous electrolyte solutions comprise a liquid electrolyte medium; a lithium-containing salt; 4-bromomethyl-1,3-dioxolan-2-one, and at least one electrochemical additive.

This invention provides nonaqueous electrolyte solutions for lithium batteries. The nonaqueous electrolyte solutions comprise a liquid electrolyte medium; a lithium-containing salt; 4-bromomethyl-1,3-dioxolan-2-one, and at least one electrochemical additive.

The present invention relates to a solid electrolyte interphase composition having a F:CF.sub.3 mol-ratio (x) of 0.00<x≤12.00; a negative electrode comprising a negative electrode material and a solid electrolyte interphase composition on a surface of said negative electrode material, wherein said solid electrolyte interphase composition has a molar ratio F:CF.sub.3 (x) of 0.00<x≤12.00, as determined by XPS; as well as its application in a lithium secondary battery cell.

A liquid composition is for use to feed carrier ions to a non-aqueous electrolyte secondary battery. The liquid composition includes a solvent and a dissolved substance. The dissolved substance includes an ionic compound. The ionic compound consists of a radical anion of an aromatic compound and a metal cation. The aromatic compound is a polyacene or a polyphenyl. The metal cation is an ion of the same type as the carrier ions.

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 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.