The present invention relates to a method for forming an SEI layer on an anode by using a non-electrochemical process for alkaliating anodes, resulting in reductions of the manufacturing capital requirements, time investments and energy consumed during industrial battery production.

An additive, a non-aqueous electrolyte solution including the same, and a lithium secondary battery including the same are disclosed herein. In some embodiments, a non-aqueous electrolyte solution includes a lithium salt, a non-aqueous solvent including a propyl propionate, and a compound represented by Formula 1:

##STR00001##

wherein, in Formula 1, R.sub.1 and R.sub.2 are each independently hydrogen or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.

The present disclosure relates to an electrolyte for a lithium-sulfur battery including a non-aqueous organic solvent including specific three types of compounds, and a lithium-sulfur battery including the same.

A negative electrode active material includes a silicon-based alloy represented by Si-M.sub.1-M.sub.2-C—B, wherein M.sub.1 and M.sub.2 are different from each other and are each independently selected from magnesium, aluminum, titanium, vanadium, chromium, iron, cobalt, nickel, copper, zinc, gallium, germanium, manganese, yttrium, zirconium, niobium, molybdenum, silver, tin, tantalum, and tungsten. In the silicon-based alloy, Si is in a range of about 50 at % to about 90 at %, M.sub.1 is in a range of about 10 at % to about 50 atom %, and M.sub.2 is in a range of 0 at % to about 10 at %, based on a total number of Si, M.sub.1, and M.sub.2 atoms. C is in a range of about 0.01 to about 30 parts by weight, and B is in a range of 0 to about 5 parts by weight, based on a total of 100 parts by weight of Si, M.sub.1, and M.sub.2.

A lithium metal battery including: a lithium negative electrode including lithium metal; a positive electrode; and an electrolyte interposed between the lithium negative electrode and the positive electrode, wherein the electrolyte contains non-fluorine substituted ether, which is capable of solvating lithium ions, a fluorine substituted ether represented by the following Formula 1, and a lithium salt, wherein an amount of the fluorine substituted ether represented by Formula 1 is greater than an amount of the non-fluorine substituted ether,
R—{O(CH.sub.2).sub.a}.sub.b—CH.sub.2—O—C.sub.nF.sub.2nH  Formula 1 wherein R is —C.sub.mF.sub.2mH or —C.sub.mF.sub.2m+1, n is an integer of 2 or greater, m is an integer of 1 or greater, a is an integer of 1 or 2, and b is 0 or 1.

The present invention relates to an electrolyte additive including a compound containing a substituent represented by Chemical Formula 1, an electrolyte including the electrolyte additive, and a secondary battery including the electrolyte. Chemical Formula 1:

##STR00001##

In Chemical Formula 1, P and O are phosphorus and oxygen, respectively; A is a bond or oxygen; Q is oxygen or an unshared electron pair; R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are each independently hydrogen, a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group, an alkynyl group, an alkoxy group, an alkoxycarbonyl group, an alkoxyalkyl group, a fluoroalkyl, or a cyclic sulfate; optionally, R.sub.1 or R.sub.2 is connected to R.sub.3 or R.sub.4 to form a double bond or a ring; n is an integer from 0 to 3; and * is a binding position.

There is provided a nonaqueous electrolytic solution for an energy storage device which is a nonaqueous electrolytic solution having an electrolyte salt dissolved in a nonaqueous solvent and contains a phosphonate represented by the following general formula (I), and an energy storage device using the same:

##STR00001##

wherein, R.sup.1 represents an alkenyl group having 2 to 6 carbon atoms or an alkynyl group having 3 to 6 carbon atoms, and R.sup.2 and R.sup.3 each independently represent an alkynyl group having 3 to 6 carbon atoms.

An electrolyte composition for batteries is provided. The electrolyte composition includes ethylene carbonate, diethyl carbonate, ethyl methyl carbonate, vinyl ethylene carbonate, vinyl carbonate, 1,3-propane sultone, ethylene sulfate, and lithium difluorophosphate. The ethylene carbonate, the diethyl carbonate, and the ethyl methyl carbonate are each present in the electrolyte composition in an amount from 10 parts by weight to 50 parts by weight based on 100 parts by weight of the electrolyte composition. The vinyl ethylene carbonate is present in an amount up to 0.5 parts by weight based on 100 parts by weight of the electrolyte composition. The vinyl carbonate is present in an amount up to 1.0 parts by weight based on 100 parts by weight of the electrolyte composition. The 1,3-propane sultone is present in an amount up to 1.5 parts by weight based on 100 parts by weight of the electrolyte composition.

A non-aqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a non-aqueous electrolyte. The negative electrode includes a negative electrode material mixture containing a negative electrode active material capable of electrochemically absorbing and releasing lithium ions, and carbon nanotubes. The negative electrode active material includes a silicon-containing material and a carbonaceous material. The non-aqueous electrolyte includes at least one cyclic ester selected from the group consisting of a cyclic sulfate ester, a cyclic sulfite ester, and a sultone. A content of the carbon nanotubes in the negative electrode material mixture is 0.005 mass% or more and 0.05 mass% or less.

In initial charge and discharge, decomposition products or a gas is generated, degrading a battery. At least one of solvents (e.g., ethylene carbonate) used for an electrolytic solution is brought into contact with a positive electrode and a negative electrode and then charge is performed to some degree, and after that, a different solvent or electrolytic solution (e.g., ethyl methyl carbonate or vinylene carbonate) was added to adjust the electrolytic solution and then charge is performed. Through this process, stable coating films are formed in initial charge and discharge, which stably inhibits a side reaction between the electrolytic solution and an active material.