The present disclosure relates to a lithium secondary battery containing tellurium as an additive for a positive electrode and bis (2,2,2-trifluoroethyl)ether as an additive for an electrolyte solution, which has an effect of improving the lifetime characteristic of the lithium secondary battery.

An electrolyte solution additive, an electrolyte solution including the same, and a lithium secondary battery including the same are disclosed herein. In some embodiments, an electrolyte solution additive includes a compound represented by Formula 1:

##STR00001##

Wherein X is oxygen (O) or sulfur (S), and R is a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms or N(R.sub.1).sub.2, wherein R.sub.1 is hydrogen or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms. The additive has an excellent effect of scavenging a decomposition product generated from a lithium salt and simultaneously forming a robust film on a surface of a positive electrode.

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.

The present disclosure relates to an electrolyte solution for a lithium-sulfur secondary battery comprising a lithium salt, a non-aqueous solvent and a cyclic anhydride compound, and a lithium-sulfur secondary battery containing the same.

The present invention provides for an electrolyte composition comprising an ether solvent, an amphiphilic molecule, an electrolyte solvent, and a lithium salt.

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.

An electrochemical cell comprises an anode, a cathode and an electrolyte composition, wherein the anode comprises as anode active material a combination of at least a carbon material and a silicon material; and the electrolyte composition comprises a solvent, from 0.5 wt. % to 70 wt. %, based on the total weight of the electrolyte, of a fluorinated acyclic carbonate compound, from 0.5 wt. % to 10 wt. %, based on the total weight of the electrolyte, of a fluorinated cyclic carbonate compound; and an electrolyte salt.

The present invention relates to a sulfolane-based electrolyte composition suitable for Lithium secondary batteries, comprising lithium bis(trifluoromethansolfonyl)imide (LiTFSI) in an amount (x) of 39.0 vol %≤x≤47.5 vol %, fluoroethylene carbonate (FEC) in an amount (y) of 0<y≤15 vol %, equivalent to an amount of 0<y≤14.0 wt. %, relative to the total volume, respectively weight, of the electrolyte composition, and sulfolane, wherein SL/LiTFSI is comprised in a molar ratio (z) of 2≤z≤3.5 as well as its application in a Lithium secondary battery cell.

The present invention provides an anode composition comprising (i) a core material (10) comprising a microparticle; (ii) a lithium alloy of said microparticle (14) on a surface of said core material (10); and (iii) a solid electrolyte interface (“SEI”) comprising (a) a LiF and (b) a polymer. The microparticle comprises Si, Al, Bi, Sn, Zn, or a mixture thereof. The present invention also relates to an electrolyte comprising a high lithium fluoride salt concentration in a low reduction potential solvent that is used produce the solid electrolyte interface comprising LiF and a polymer. The anode composition of the invention has an initial coulombic efficiency of at least 90%, a cycling coulombic efficiency of at least 99%, or both.

An exemplary lithium-ion battery may include an anode, a cathode, and a separator between the anode and cathode. The separator may be at least partially coated with a sub-nanometer porous membrane. The battery may be a conventional battery in which the anode and cathode are at least partially submerged in an electrolytic solution. Alternatively, the battery may be a solid-state battery disposed between the anode and cathode and having a solid-state electrolyte, which may serve as the separator.