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.

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 preparation method of a composite anode material of micrometer-sized carbon-coated silicon and carbon includes: subjecting micrometer-sized silicon particles to a chemical vapor deposition reaction under a gas atmosphere containing carbon to obtain carbon-coated first micrometer-sized silicon particles; dispersing the carbon-coated first micrometer-sized silicon particles in a first mixed solvent to obtain a dispersed solution; adding alkali into the dispersed solution and heating the dispersed solution to obtain carbon-coated second micrometer-sized silicon particles; dispersing the carbon-coated second micrometer-sized silicon particles and graphene oxide in a second mixed solvent that are subjected to a hydrothermal reaction to obtain a composite hydrogel of reduced graphene oxide, silicon, and carbon; and heating the hydrogel to obtain the composite anode material.

An electrolyte of a lithium-ion secondary battery and an application thereof. The electrolyte of the lithium-ion secondary battery includes an organic solution, a lithium salt, and an additive, and the additive comprises a borate compound. The electrolyte can be better applied to low-cobalt or cobalt-free positive electrode materials, improve the high-temperature cycle and storage performance of the lithium-ion batteries, and inhibit gas generation during high-temperature storage, thereby improving the comprehensive performance of the battery.

A negative electrode material includes silicon composite particles. The silicon composite particles include amorphous silicon particles and a buffer phase. The amorphous silicon particles are dispersed in the buffer phase. A non-uniformity of the amorphous silicon particles dispersed in the buffer phase is less than or equal to 30%. Also, an electronic device including the negative electrode material.

A negative electrode material includes a composite of a silicon-based material (1), a polymer (2), and carbon nanotubes (3), where the polymer (2) contains a first group and a second group, the first group is chemically bonded to the carbon nanotubes (3), and the second group is chemically bonded to the silicon-based material (1). Both the carbon nanotubes (3) and the polymer (2) containing two groups are applied to surfaces of particles of the silicon-based material (1). The two groups of the polymer (2) are chemically bonded to the silicon-based material (1) and the carbon nanotubes (3) respectively, so that bonding force between the silicon-based material (1) and the carbon nanotubes (3) is enhanced and a uniform carbon nanotube (3) coating layer is formed. This can significantly improve conductive performance of the silicon-based material (1), thereby improving cycling performance and rate performance of an electrochemical apparatus.

A separator structure for a secondary battery includes: a porous substrate; an intermediate layer on the porous substrate and including lithium fluoride (LiF) and a defluorinated polymer; and a lithium metal layer on the intermediate layer. An anode-separator assembly for a secondary battery includes an anode comprising an anode current collector and an anode active material layer on a surface of the anode current collector, and the separator structure. A secondary battery includes the anode-separator assembly, and a cathode on the porous substrate of the anode-separator assembly.

A production method is provided in which submicronic particles containing silicon are incorporated into a matrix, wherein, during the incorporation of the particles, the particles are in a compacted state with a bulk density of more than 0.10 grams per cubic centimeter, and the compacted particles have a specific surface area at least 70% of that of the particles considered separately without contact between each other.

A multistage centrifugal atomizer comprises an outer shell that contains an inlet port and an outlet port and that encloses a tundish, a first inclined rotating surface and a second inclined rotating surface. The first inclined rotating surface is opposedly disposed to the second inclined rotating surface. The inlet is used to introduce a molten material into the multistage atomizer and the outlet is used to remove ultrafine particles having a D50 of less than 20 micrometers.

Additives for energy storage devices comprising nitrogen-containing compounds are disclosed. The energy storage device comprises a first electrode and a second electrode, where 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, and an electrolyte composition. Nitrogen-containing compounds may serve as additives to the first electrode, the second electrode, and/or the electrolyte, as well as the separator.