A purpose of the present invention is to provide a lithium ion secondary battery having improved battery characteristics. The lithium ion secondary battery according to the present invention comprises a negative electrode comprising a negative electrode active material comprising a silicon material and an electrolyte solution comprising an electrolyte solvent comprising an open chain sulfone compound, a fluorinated cyclic carbonate and an open chain carbonate and a supporting salt comprising LiN(FSO.sub.2).sub.2.

A lithium ion battery according to the present invention comprises a positive electrode, a negative electrode, a positive electrode lead that is connected to the positive electrode, an insulation tape that covers the positive electrode lead, and an electrolyte solution. The insulation tape comprises a base material layer that is mainly composed of an organic material, and a filler layer that is provided on the base material layer; the filler layer contains an oxide compound of an alkaline earth metal; and the electrolyte solution contains fluorine.

Disclosed are: a non-aqueous electrolyte for a lithium secondary battery containing 1-20 parts by weight of a cyano group-containing pyrimidine-based compound on the basis of 100 parts by weight of an organic solvent; and a lithium secondary battery comprising the same.

A metal-ion battery cell is provided that comprises anode and cathode electrodes, a separator, and an electrolyte. The anode electrode may, for example, have a capacity loading in the range of about 2 mAh/cm2 to about 10 mAh/cm2 and comprise anode particles that (i) have an average particle size in the range of about 0.2 microns to about 40 microns, (ii) exhibit a volume expansion in the range of about 8 vol. % to about 180 vol. % during one or more charge-discharge cycles of the battery cell, and (iii) exhibit a specific capacity in the range of about 600 mAh/g to about 2600 mAh/g. The electrolyte may comprise, for example, (i) one or more metal-ion salts and (ii) a solvent composition that comprises one or more low-melting point solvents that each have a melting point below about −70° C. and a boiling point above about +70° C.

The present invention pertains to an anode-less lithium ion battery comprising a) a cathode comprising a cathode current collector and a cathode electro-active material on the cathode current collector; b) an anode current collector; c) a liquid electrolyte composition between the a) cathode and the b) anode current collector; and d) a separator, wherein the c) liquid electrolyte composition comprises i) at least 70% by volume (vol %) of a solvent mixture with respect to the total volume of the electrolyte composition, comprising at least one fluorinated ether compound and at least one non-fluorinated ether compound, and ii) at least one lithium salt.

A lithium-ion battery separator includes a substrate defining inter-particle pores and a zeolite coating on a surface of the substrate. The zeolite coating includes zeolite particles. The zeolite particles are hydrophobic and have an average diameter smaller than an average pore size of inter-particle pores of the substrate, such that some of the zeolite particles are positioned in some of the inter-particle pores. The separator is non-flammable In a lithium-ion battery, the substrate is a first electrode, and a second electrode is in direct contact with the zeolite coating. The lithium-ion battery includes a non-flammable salt-concentrated electrolyte, and the zeolite coating has a high wettability for the electrolyte. The lithium-ion battery is non-flammable.

Disclosed is an electrolyte composition comprising: a) a solvent comprising: i) either a mixture of 1,1,1,3,3,3-hexaflu-oro-2-methoxypropane (HFMP) or of 1,1,1,3,3,3-hexafluoro-2-(fluoromethoxy)propane (HFMFP), of monofluoroethylene carbonate (F1EC) and of 2,2,2-trifluoroethyl methyl carbonate (F3EMC), ii) or a mixture of 1,1,1,3,3,3-hexafluoro-2-methoxypropane (HFMP) or of 1,1,1,3,3,3-hexafluoro-2-(fluoromethoxy)propane (HFMFP), of monofluoroethylene carbonate (F1EC) and of 2,2,2-trifluoroethyl acetate (F3EA), b) at least one lithium salt, the cation of which is the cation of an alkali metal.

Electrolytes and electrolyte additives for energy storage devices comprising a sulfonate ester compound 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, and at least one electrolyte additive selected from a sulfonate ester compound.

An electrolyte composition for a battery is provided. The electrolyte composition includes a lithium salt in a carbonate-based solution and lithium difluoro(oxalate)borate present in the electrolyte composition in an amount from 0.1 part by weight to 5 parts by weight based on 100 parts by weight of the electrolyte composition.

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.