There is provided a method for producing lithium difluorophosphate in which difluorophosphate ester reacts with a lithium salt compound in a nonaqueous organic solvent without using water as a raw material, a method for producing a difluoro phosphate ester including a step of allowing a dihalophosphate ester to react with a fluorinating agent having a concentration of contained hydrogen fluoride of 15 mol % or less in a nonaqueous organic solvent; lithium difluorophosphate in which a value of a relational expression (d90-d10)/MV represented by d90 which is a particle size at which a volume cumulative distribution is 90%, d10 which is a particle size at which a volume cumulative distribution is 10%, and MV which is a volume average particle size is 10 or less; and methods for producing a nonaqueous electrolytic solution and a nonaqueous secondary battery using the production method described above.

The present invention discloses a triphenylsulfonium salt compound as shown in the general formula (I), wherein R.sub.1 represents an electron-withdrawing group and R.sub.2 represents an amplification group. Said compound shows significantly enhanced solubility and photosensitivity compared with unsubstituted triphenylsulfonium salts, and has significantly advantageous performance compared with prior art improved substitutes.

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The present invention discloses a triphenylsulfonium salt compound as shown in the general formula (I), wherein R.sub.1 represents an electron-withdrawing group and R.sub.2 represents an amplification group. Said compound shows significantly enhanced solubility and photosensitivity compared with unsubstituted triphenylsulfonium salts, and has significantly advantageous performance compared with prior art improved substitutes. ##STR00001##

The present invention relates to a lithium secondary battery including a positive electrode including a positive active material layer, the positive active material layer including a positive active material and a carbonaceous nanostructure; a negative electrode including a negative active material; and an electrolyte. The electrolyte includes a non-aqueous organic solvent, a lithium salt, and an additive including a compound represented by Chemical Formula 1, wherein the amount of the carbonaceous nanostructure is about 0.5 wt % or more and less than 4 wt % based on 100 wt % of the total amount of the positive active material layer. ##STR00001## wherein, in Chemical Formula 1, A is a substituted or unsubstituted aliphatic chain or (—C.sub.2H.sub.4—O—C.sub.2H.sub.4-)n, and n is an integer from 1 to 10.

The present invention relates to a lithium secondary battery including a positive electrode including a positive active material, the positive active material including a nickel-containing lithium transition metal compound; a negative electrode including a negative active material; and an electrolyte including a non-aqueous organic solvent, a lithium salt, and an additive comprising a compound represented by Chemical Formula 1, wherein the content of Ni is 60 mol % or more based on 100 mol % of the total transition metals in the lithium transition metal compound. ##STR00001## wherein, in Chemical Formula 1, A is a substituted or unsubstituted aliphatic chain or (—C.sub.2H.sub.4—O—C.sub.2H.sub.4—)n, and n is an integer from 1 to 10.

The present invention relates to a non-aqueous electrolyte solution additive, and a non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery which comprise the same, wherein, specifically, since the non-aqueous electrolyte solution, which comprises a compound capable of maintaining a passive effect by increasing an effect of forming a solid electrolyte interface (SEI) on surfaces of a positive electrode and a negative electrode, is provided, high-temperature storage characteristics and life characteristics of the lithium secondary battery may be improved.

The present invention relates to a non-aqueous electrolyte solution additive, and a non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery which comprise the same, wherein, specifically, since the non-aqueous electrolyte solution, which comprises a compound capable of maintaining a passive effect by increasing an effect of forming a solid electrolyte interface (SEI) on surfaces of a positive electrode and a negative electrode, is provided, high-temperature storage characteristics and life characteristics of the lithium secondary battery may be improved.

A sulfonium salt is formed of a sulfonium cation selected from a group indicated by general formulas (1), (2), and (3) and a gallate anion represented by formula (a). A photoacid generator is characterized in that said sulfonium salt is contained therein. An energy-ray curable composition contains the acid generator and a cationic polymerizable compound. A cured product is formed by curing these substances. ##STR00001##

The present invention relates to a lithium secondary battery including a positive electrode including a positive active material layer, the positive active material layer including a positive active material and a carbonaceous nanostructure; a negative electrode including a negative active material; and an electrolyte. The electrolyte includes a non-aqueous organic solvent, a lithium salt, and an additive including a compound represented by Chemical Formula 1, wherein the amount of the carbonaceous nanostructure is about 0.5 wt % or more and less than 4 wt % based on 100 wt % of the total amount of the positive active material layer.

##STR00001## wherein, in Chemical Formula 1, A is a substituted or unsubstituted aliphatic chain or (C.sub.2H.sub.4OC.sub.2H.sub.4-)n, and n is an integer from 1 to 10.

The present invention relates to a lithium secondary battery including an electrolyte including a non-aqueous organic solvent, a lithium salt and an additive comprising a compound represented by Chemical Formula 1; and a battery case in which the electrolyte is housed, wherein the battery case has a shape with a width (W), a height (H), and a thickness (Th), when a maximum value among the width (W), the height (H), and the thickness (Th) is a and a minimum value among the width (W), the height (H), and the thickness (Th) is b, b/a is 0.01 or more:

##STR00001## wherein, in Chemical Formula 1, A is a substituted or unsubstituted aliphatic chain or (C.sub.2H.sub.4OC.sub.2H.sub.4-)n, and n is an integer from 1 to 10.