A flame-resistant polymer composite separator for use in a lithium battery, wherein the polymer composite separator comprises (a) a binder or matrix polymer; (b) 0.1% to 50% by weight of a lithium salt dispersed in the polymer; and (c) from 30% to 99% by weight of particles or fibers of an inorganic material or polymer fibers that are dispersed in or bonded by the polymer, wherein the polymer is a polymerization or crosslinking product of a reactive additive comprising (i) a first liquid solvent that is polymerizable, (ii) an initiator or crosslinking agent, and (iii) the lithium salt and wherein the polymer composite separator has a thickness from 50 nm to 100 μm and a lithium ion conductivity from 10.sup.−8 S/cm to 5×10.sup.−2 S/cm at room temperature.

A lithium battery includes a cathode including a cathode active material; an anode including an anode active material; and an organic electrolytic solution between the cathode and the anode, wherein the anode active material includes a carbonaceous anode active material and a metallic anode active material, in an XRD spectrum of the anode, a peak intensity ratio (la/lb) of a peak intensity (la) of a carbonaceous anode active material oriented in a direction non-parallel to a surface of the anode to all peak intensities (lb) of the carbonaceous anode active material oriented in all directions is about 0.15 or more, and the organic electrolytic solution includes a first lithium salt, an organic solvent, and a bicyclic sulfate-based compound represented by Formula 1 below:

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Electric batteries wherein the positively charged electrode contacts an aqueous layer containing material which is reduced during electric discharge and/or metal ions are transported through special electrolyte that inhibits dendritic deposition on the negatively charged electrode. Methods described include electrolyte compositions including organoborate anions and cations with low charge density, and aqueous solutions containing bromate and/or bromide anions and high concentrations of dissolved salts.

Disclosed is a nonaqueous electrolyte solution containing a lithium electrolyte, methyl 3,3,3-trifluoropropionate, and a phosphazene compound. Preferably, the phosphazene compound is a cyclic phosphazene compound represented by the disclosed general formula (I).

A non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery including the same are disclosed herein. In some embodiments, a non-aqueous electrolyte solution includes a lithium salt at a concentration of 1.5 M to 2.0 M, an organic solvent containing ethylene carbonate and ethyl propionate, and a first additive represented by Formula 1, wherein the ethylene carbonate and the ethyl propionate are present in a volume ratio of 1:9 to 1.5:8.5:

NC—R—CH═CH—R.sub.1—CN   [Formula 1]

In Formula 1, R and R.sub.1 are each independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

The invention provides a method of recovering a lithium electrolyte salt from a used electrolyte, the method comprising: contacting a used electrolyte comprising a lithium electrolyte salt and electrolyte solvent with a polar aprotic solvent to produce a solution comprising the lithium electrolyte salt, the electrolyte solvent and the polar aprotic solvent, wherein at least one of the electrolyte solvent and the polar aprotic solvent comprises carbonate solvent, combining the solution with a precipitation solvent in which the lithium electrolyte salt is poorly soluble; precipitating a precipitated composition comprising the lithium electrolyte salt solvated by the carbonate solvent from a solvent mixture comprising the polar aprotic solvent, the precipitation solvent and the electrolyte solvent, wherein the precipitated composition precipitates as a solid or as a liquid; and separating the precipitated composition from the solvent mixture.

A non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery including the same are disclosed herein. In some embodiments, a non-aqueous electrolyte solution for a lithium secondary battery includes a lithium salt, an organic solvent containing a carbonate compound and a propionate compound, a first additive containing a compound represented by the following Formula 1, and a second additive containing 1,3,6-hexanetricarbonitrile, wherein the first additive and the second additive are present in a weight ratio of 1:1.1 to 1:5.5,

NC—R—CH═CH—R—CN  [Formula 1] wherein, in Formula 1, R is an unsubstituted or substituted alkylene group having 1 to 5 carbon atoms.

Separator systems for electrochemical systems providing electronic, mechanical and chemical properties useful for applications including electrochemical storage and conversion. Separator systems include structural, physical and electrostatic attributes useful for managing and controlling dendrite formation and for improving the cycle life and rate capability of electrochemical cells including silicon anode based batteries, air cathode based batteries, redox flow batteries, solid electrolyte based systems, fuel cells, flow batteries and semisolid batteries. Separators include multilayer, porous geometries supporting excellent ion transport properties, providing a barrier to prevent dendrite initiated mechanical failure, shorting or thermal runaway, or providing improved electrode conductivity and improved electric field uniformity, as well as composite solid electrolytes with supporting mesh or fiber systems providing solid electrolyte hardness and safety with supporting mesh or fiber toughness and long life required for thin solid electrolytes without fabrication pinholes or operationally created cracks.

According to one embodiment, provided is a nonaqueous electrolyte battery including a positive electrode, a negative electrode, and a nonaqueous electrolyte. The positive electrode includes lithium manganese composite oxide particles having a spinel crystal structure and lithium cobalt composite oxide particles. The negative electrode includes a titanium-containing oxide. The nonaqueous electrolyte contains a propionate ester. The battery satisfies 0.8≤p/n≤1.2 and 1≤w/s≤60. p denotes a capacity per unit area of the positive electrode. n denotes a capacity per unit area of the negative electrode. w denotes a content of the propionate ester in the nonaqueous electrolyte and is in a range of 10% by weight to 60% by weight. s denotes an average particle size of the lithium manganese composite oxide particles.

Use of a compound of Formula (I) in a nonaqueous battery electrolyte formulation (1) wherein R is a fluorinated alkyl group and X is selected from the group consisting of F, Cl, H, CF.sub.3, and C.sub.1 to C.sub.6 alkyl which may be at least partially fluorinated and —OR group can be cis- or trans- to any other group X.

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