A negative electrode material for a secondary battery includes a matrix containing silicon oxide, a composite oxide of one or more doping elements selected from an alkali metal, an alkaline earth metal, and a post-transition metal, and silicon, or a mixture thereof; and silicon nanoparticles dispersed and embedded in the matrix.

A negative electrode material for a secondary battery includes a matrix containing silicon oxide, a composite oxide of one or more doping elements selected from an alkali metal, an alkaline earth metal, and a post-transition metal, and silicon, or a mixture thereof; and silicon nanoparticles dispersed and embedded in the matrix.

In certain embodiments, a method includes forming a battery electrode on a substrate. Forming the battery electrode on the substrate includes depositing a first electrode active material layer on a first portion of a surface of the substrate and depositing, to form a current collector, a conductive material using a thin film deposition process on a surface of the first electrode active material layer. The conductive material is deposited over an edge of the first electrode active material layer and onto a second portion of the surface of the substrate, the second portion of the substrate being adjacent to the first portion of the substrate. The method includes removing the battery electrode from the substrate, the battery electrode including the first electrode active material layer and the current collector.

In certain embodiments, a method includes forming a battery electrode on a substrate. Forming the battery electrode on the substrate includes depositing a first electrode active material layer on a first portion of a surface of the substrate and depositing, to form a current collector, a conductive material using a thin film deposition process on a surface of the first electrode active material layer. The conductive material is deposited over an edge of the first electrode active material layer and onto a second portion of the surface of the substrate, the second portion of the substrate being adjacent to the first portion of the substrate. The method includes removing the battery electrode from the substrate, the battery electrode including the first electrode active material layer and the current collector.

A negative electrode for a lithium secondary battery, a method for preparing a negative electrode for a lithium secondary battery, and a lithium secondary battery including the negative electrode. The negative electrode for a lithium secondary battery includes a negative electrode current collector layer, a first negative electrode active material layer on one surface or both surfaces of the negative electrode current collector layer, and a second negative electrode active material layer on a surface opposite to a surface of the first negative electrode

A lithium secondary battery includes a positive electrode, and a negative electrode in which deposition and dissolution reactions of lithium metal occur. The negative electrode includes a negative electrode layer. The negative electrode layer contains, as a negative electrode active material, an alloy of the lithium metal and dissimilar metal. An element percentage of lithium element in the alloy is 40.00 atomic % or more and 99.97 atomic % or less when the lithium secondary battery is fully charged.

A lithium secondary battery includes a positive electrode, and a negative electrode in which deposition and dissolution reactions of lithium metal occur. The negative electrode includes a negative electrode layer. The negative electrode layer contains, as a negative electrode active material, an alloy of the lithium metal and dissimilar metal. An element percentage of lithium element in the alloy is 40.00 atomic % or more and 99.97 atomic % or less when the lithium secondary battery is fully charged.

There is provided an electrode layer for an all-solid state battery, which contains an electrode active material and a sulfide solid electrolyte, where the sulfide solid electrolyte has an average particle diameter of less than 1 .Math.m and the electrode layer contains an imidazoline-based dispersion material.

There is provided an electrode layer for an all-solid state battery, which contains an electrode active material and a sulfide solid electrolyte, where the sulfide solid electrolyte has an average particle diameter of less than 1 .Math.m and the electrode layer contains an imidazoline-based dispersion material.

This application discloses a secondary battery and a device containing the secondary battery. A positive active material of the secondary battery includes one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and a modified material thereof. A negative active material of the secondary battery includes a silicon-oxygen compound and graphite. A separator of the secondary battery includes a substrate and a coating layer. The secondary battery satisfies:

[00001]$7.5\le \frac{3460}{ED}-\left(D50-D_{C}50\times 0.75-\frac{T}{18}\right)\le 11.5,$

where ED≥270 Wh/Kg, 11 μm≤D50≤18.5 μm, 11 μm≤D.sub.C50≤20 μm. The secondary battery according to this application achieves relatively high cycle performance while achieving a relatively high energy density concurrently.