The present disclosure relates to a non-aqueous electrolyte solution for a lithium secondary battery, and the non-aqueous electrolyte solution includes: a lithium salt; an organic solvent; and an additive including vinylene carbonate, vinyl ethylene carbonate, and a compound represented by chemical formula 1:

##STR00001##

Herein, each of R1 to R3 is independently hydrogen or an alkyl group having 1 to 3 carbon atoms.

Electrolytes and electrolyte additives for energy storage devices comprising phosphazene based 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 comprising at least two electrolyte co-solvents, wherein at least one electrolyte co-solvent comprises a phosphazene based compound.

The present application provides an electrolyte, the electrolyte including a fluorinated metal salt with S═O or P═O; and a titanate with a structural formula Ti—(O—R.sub.1).sub.4, where the R1 is selected from one or more of C.sub.1-C.sub.6 alkyl, C.sub.1-C.sub.6 halogenated alkyl, C.sub.2-C.sub.6 alkenyl, C.sub.2-C.sub.6 alkynyl or C.sub.1-C.sub.6 silyl, and a secondary battery including the electrolyte, a battery module, a battery pack and a power consumption apparatus.

An electrolyte for use in a lithium-ion or sodium-ion battery includes a salt such as a lithium salt, a sodium salt, or a mixture of any two or more thereof; and a solvent that includes a compound represented as Formula I, II, or a mixture of any two or more thereof:

##STR00001##

wherein: R.sup.1 is substituted or unsubstituted alkyl, substituted or unsubstituted haloalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted polyether; R.sup.2 is F, a fluoroalkyl, fluorocycloalkyl; R.sup.3 is F, a fluoroalkyl, fluorocycloalkyl; and R.sup.4 is substituted or unsubstituted alkyl, substituted or unsubstituted haloalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, or substituted or unsubstituted polyether; and R.sup.5 is a fluoroalkyl or fluorocycloalkyl.

The present disclosure provides a non-aqueous electrolyte including an additive for a non-aqueous electrolyte represented by Formula 1 below:

##STR00001##

wherein, R.sub.1 to R.sub.5 may each independently be any one selected from the group consisting of H, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkenyl group having 3 to 12 carbon atoms, and a nitrile group.

A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a nonaqueous electrolyte, wherein the negative electrode includes a negative electrode current collector, and a negative electrode active material layer supported by the negative electrode current collector and containing a silicon material as a negative electrode active material; when dividing the negative electrode active material layer into two layers of a first region and a second region having the same thickness, the second region is closer to the negative electrode current collector than the first region; the silicon material is contained in the first region more than the second region; and the nonaqueous electrolyte includes at least one additive selected from the group consisting of a sulfite compound and a sulfate compound.

The present disclosure is directed to a phosphorus-modified ionic liquid compound, the synthesis thereof and an electrochemical cell electrolyte containing the phosphorus-modified ionic liquid compound.

The present disclosure discloses a primary lithium battery comprising a reactive solid cathode, a liquid electrolyte, a separator, and a lithium anode. The liquid electrolyte is ionic conductive and is configured to undergo a series coupling reaction after solid phase reaction of the reactive solid cathode and the lithium anode. The liquid electrolyte comprises a solvent and an electrolyte salt, and a concentration of the electrolyte salt in the liquid electrolyte is 0.1-3 mol/L. The solvent comprises a sulfite ester type compound and an organic solvent, and a concentration of the sulfite ester type compound in the organic solvent is 5 wt % to 90 wt %.

An electrolyte solution containing a solvent. The solvent contains a compound (1) represented by the following formula (1), wherein R.sup.a, R.sup.b, R.sup.c, and R.sup.d are the same as or different from each other, and are each —H, —F, —CH.sub.3, or —CF.sub.3; at least one of R.sup.a, R.sup.b, R.sup.c, or R.sup.d is —F or —CF.sub.3; and at least one of R.sup.a, R.sup.b, R.sup.c, or R.sup.d is —CH.sub.3, and a compound (2) represented by the following formula (2), wherein R.sup.e is a C1-C5 linear or branched alkyl or alkoxy group optionally containing an ether bond; R.sup.f is a C1-C5 linear or branched alkyl group optionally containing an ether bond; and at least one of R.sup.e or R.sup.f contains a fluorine atom. Also disclosed is an electrochemical device including the electrolyte solution, a lithium-ion secondary battery including the electrolyte solution and a module including the electrochemical device. ##STR00001##

An electrolyte solution capable of constituting a secondary battery in which a volume change due to charge and discharge is small and cycle characteristics are excellent is provided. The present example embodiment relates to an electrolyte solution for a lithium ion secondary battery comprising a fluorinated ether and a cyclic dicarboxylic acid ester.