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 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.

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 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.

The present disclosure provides a non-aqueous electrolyte including an additive including a repeating unit represented by Formula 1 and a repeating unit represented by Formula 2 below:

##STR00001##

##STR00002##

wherein X, R, R.sub.1 and R.sub.2 are described herein.

The present disclosure provides a non-aqueous electrolyte including an additive including a repeating unit represented by Formula 1 and a repeating unit represented by Formula 2 below:

##STR00001##

##STR00002##

wherein X, R, R.sub.1 and R.sub.2 are described herein.

A non-aqueous electrolyte, with a coulombic efficiency with respect to lithium of at least 80%, that includes a Group 1 salt dissolved in a mixture containing two sulfone compounds, a mixture containing a sulfone compound and a sultone compound, and/or a mixture containing a sulfone compound and a sulfonamide compound. The Group 1 salt can be a lithium salt, the sulfone compound can be a cyclic sulfone such as thietane-1,1-dioxide and sulfolane, the sultone compound can be a cyclic sultone such as 1,3-propane sultone, and the sulfonamide compound can be a partially fluorinated sulfonamide such as 1,1,1-trifluoro-N,N-dimethylmethanesulfonamide and N-butyl-1,1,1-trifluoro-N-methylmethanesulfonamide. Additives such as another lithium salt, a polyunsaturated compound, a cyclic anhydride, a cyclic unsaturated sultone, and/or a cyclic phosphate can be included in the non-aqueous electrolyte.