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.

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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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 zinc ion battery includes a cathode; an anode; a separator; and an electrolyte sandwiched between the cathode and the anode. The electrolyte includes a mixture of zinc perchlorate and sodium perchlorate, and a ratio of the sodium perchlorate to zinc perchlorate is at least 30.

There is provided a sulfide solid electrolyte containing elemental lithium (Li), elemental phosphorus (P), elemental sulfur (S), and an elemental halogen (X). The mole ratio of the elemental lithium (Li) to the elemental phosphorus (P), Li/P, satisfies 3.7<Li/P<5.4. The mole ratio of the elemental sulfur (S) to the elemental phosphorus (P), S/P, satisfies 3.9<S/P<4.1. The mole ratio of the elemental halogen (X) to the elemental phosphorus (P), X/P, satisfies 0.7<X/P<2.4. The sulfide solid electrolyte includes a crystalline phase having an argyrodite-type crystal structure.

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 positive electrode comprising a current collector and a positive electrode active material layer disposed on at least one surface of the current collector, and a lithium-sulfur battery comprising the positive electrode are provided. The positive electrode active material layer comprises a positive electrode active material and an additive, and the additive comprises a transition metal-ferrocyanide compound.

A lithium-sulfur battery includes a casing, a top lid circumferentially welded to the casing, a negative contact surface positioned opposite the top lid, a positive terminal disposed within the casing, welded to the top lid, and configured as a mandrel, a glass insulator circumferentially wound around the mandrel, and a jelly roll including at least an anode and a cathode wound around the mandrel. The jelly roll may also include a top surface not in contact with the top lid, a bottom surface partially in contact with the negative contact surface, and partially in contact with a plurality of non-hollow carbonaceous spherical particles disposed between the bottom surface of the jelly roll and the negative contact surface. At least some of the non-hollow carbonaceous spherical particles may provide one or more electrically-conductive pathways between the bottom surface and the negative contact surface.

A lithium-sulfur battery includes a casing, a top lid circumferentially welded to the casing, a negative contact surface positioned opposite the top lid, a positive terminal disposed within the casing, welded to the top lid, and configured as a mandrel, a glass insulator circumferentially wound around the mandrel, and a jelly roll including at least an anode and a cathode wound around the mandrel. The jelly roll may also include a top surface not in contact with the top lid, a bottom surface partially in contact with the negative contact surface, and partially in contact with a plurality of non-hollow carbonaceous spherical particles disposed between the bottom surface of the jelly roll and the negative contact surface. At least some of the non-hollow carbonaceous spherical particles may provide one or more electrically-conductive pathways between the bottom surface and the negative contact surface.