The present invention provides a composition for a gel polymer electrolyte, the composition including a first oligomer represented by Formula 1, a second oligomer including a first repeating unit represented by Formula 2a derived from a styrene monomer, a polymerization initiator, a lithium salt, and a non-aqueous solvent. The present invention also provides a gel polymer electrolyte prepared using the same, and a lithium secondary battery.

The present invention provides a composition for a gel polymer electrolyte, the composition including a first oligomer represented by Formula 1, a second oligomer including a first repeating unit represented by Formula 2a derived from a styrene monomer, a polymerization initiator, a lithium salt, and a non-aqueous solvent. The present invention also provides a gel polymer electrolyte prepared using the same, and a lithium secondary battery.

Disclosed is an anodeless-type all-solid-state battery. The all-solid-state battery includes a plurality of recesses formed in an electrolyte layer and to be depressed from a surface of the electrolyte layer contacting an anode collector and thus serve as spaces for lithium to reversibly precipitate.

Disclosed is an anodeless-type all-solid-state battery. The all-solid-state battery includes a plurality of recesses formed in an electrolyte layer and to be depressed from a surface of the electrolyte layer contacting an anode collector and thus serve as spaces for lithium to reversibly precipitate.

An embodiment is directed to a solid state electrolyte-comprising Li or Li-ion battery cell, comprising an anode electrode, a cathode electrode with an areal capacity loading that exceeds around 3.5 mAh/cm.sup.2, an ionically conductive separator layer that electrically separates the anode and cathode electrodes, and one or more solid electrolytes ionically coupling the anode and the cathode, wherein at least one of the one or more solid electrolytes or at least one solid electrolyte precursor of the one or more solid electrolytes is infiltrated into the solid state Li or Li-ion battery cell as a liquid.

An embodiment is directed to a solid state electrolyte-comprising Li or Li-ion battery cell, comprising an anode electrode, a cathode electrode with an areal capacity loading that exceeds around 3.5 mAh/cm.sup.2, an ionically conductive separator layer that electrically separates the anode and cathode electrodes, and one or more solid electrolytes ionically coupling the anode and the cathode, wherein at least one of the one or more solid electrolytes or at least one solid electrolyte precursor of the one or more solid electrolytes is infiltrated into the solid state Li or Li-ion battery cell as a liquid.

A solid electrolyte includes a polymer and a lithium salt, a sodium salt or mixtures of these salts. The polymer has at least 50 mol % of recurring units of formula (I). A method is for the preparation of the electrolyte. Energy storage devices can include the electrolyte.

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A positive electrode active material for an all-solid-state lithium ion secondary battery, containing: a lithium-metal composite oxide particle having a niobium solid solution layer and a center other than the niobium solid solution layer; and a coating layer coating at least a part of a surface of the lithium-metal composite oxide particle and formed of a compound containing lithium and niobium, an average thickness of the coating layer is 2 nm or more and 1 μm or less, and an average thickness of the niobium solid solution layer is 0.5 nm or more and 20 nm or less.

A positive-electrode active material contains a lithium composite oxide containing at least one selected from the group consisting of F, Cl, N, and S. The crystal structure of the lithium composite oxide belongs to a space group C2/m. An XRD pattern of the lithium composite oxide comprises a first peak within the first range of 44 degrees to 46 degrees of a diffraction angle 2θ and a second peak within the second range of 18 degrees to 20 degrees of the diffraction angle 2θ. The ratio of the second integrated intensity of the second peak to the first integrated intensity of the first peak is within a range of 0.05 to 0.90.

An electrolyte composition including: i) at least one lithium salt; ii) at least one nonaqueous solvent; and iii) at least one product from reaction of a mixture including: a) at least one diamine selected from: a1) a linear aliphatic C2 to C24 diamine; and/or a2) a cycloaliphatic C6 to C18 diamine; and/or a3) an aromatic, preferably C6 to C24, diamine; b) at least one saturated hydroxylated C3-C36 carboxylic acid; c) at least one monoacid selected from saturated linear and non-hydroxylated C2 to C18 carboxylic acids;

the composition having a viscosity measured at 23° C. ranging from 101 to 107 mPa.Math.s.