A method for processing a negative electrode plate, a sodium-metal negative electrode plate and related devices. In a vacuum environment, the metal vapor reacts with oxygen, and the metal oxide formed by the reaction is plated on the surface of the sodium-metal negative electrode plate to form a metal oxide protective layer with high mechanical strength and stable chemical properties. The metal oxide protective layer can greatly reduce the phenomenon of low yield and performance deterioration caused by the reaction of sodium metal with air and water during the processing of the sodium-metal negative electrode plate. Since the metal oxide has a nanoscale thickness, it can form a corresponding sodium salt with sodium metal under electrochemical conditions, thereby improving the sodium ion transport rate on the surface of the sodium-metal negative electrode plate and improving the battery’s kinetic performance.

An electrode for all-solid-state secondary batteries which enables the achievement of a practicable all-solid-state secondary battery even if an electrode active material layer does not contain a solid electrolyte which has been an essential ingredient for conventional electrodes for all-solid-state secondary batteries; and a practicable all-solid-state secondary battery which uses an electrode in which an electrode active material layer does not contain a solid electrolyte. The all-solid-state secondary battery includes a positive electrode, a solid electrolyte layer and a negative electrode, the positive electrode and/or the negative electrode has an electrode active material layer on a collector, the electrode active material layer contains an electrode active material and a binder resin; the binder resin contains a polyimide resin; and the electrode active material layer does not contain a solid electrolyte, while containing a lithium salt that has a solubility of 0.1 g or more per 100 g of a solvent at 25° C. with respect to water or at least one organic solvent.

As for a secondary battery using lithium cobalt oxide as a positive electrode active material, the positive electrode active material with which a decrease in battery capacity due to repeated charge and discharge is inhibited is provided. Alternatively, a positive electrode active material particle which hardly deteriorates is provided. The positive electrode active material includes lithium, cobalt, oxygen, magnesium, aluminum, and fluorine and is a crystal represented by a layered rock-salt structure. The space group of the crystal is represented by R−3m. The concentration of fluorine in a surface portion of the crystal is higher than that inside the crystal. The concentration of magnesium in the surface portion of the crystal is higher than that inside the crystal. The atomic ratio of magnesium to aluminum in the surface portion of the crystal is higher than that inside the crystal.

Disclosed is a method of fabricating an anode for a lithium-ion battery, including milling a mixture of nano-silicon, one or more carbonaceous materials and one or more solvents, wherein the mixture is retained as a wet slurry during milling. The mixture is carbonised to produce a silicon thinly coated with carbon (Si@C) material. Further milling occurs of a second mixture of the Si@C material, one or more graphite, one or more second carbonaceous materials and one or more second solvents, wherein the second mixture is retained as a second wet slurry during milling. The second mixture is carbonised to produce a Si@C/graphite/carbon material. The anode is formed from the Si@C/graphite/carbon material.

Embodiments described herein relate to electrochemical cells and production thereof under high pressure. In some aspects, a method of producing an electrochemical cell can include disposing a cathode material onto a cathode current collector to form a cathode, disposing an anode material onto an anode current collector to form an anode, and disposing the anode onto the cathode in an assembly jig with a separator positioned between the anode and the cathode to form an electrochemical cell, the assembly jig applying a force to the electrochemical cell such that a pressure in the cathode material is at least about 3,500 kPa. In some embodiments, the cathode material can be a first cathode material, and the method can further include disposing a second cathode material onto the first cathode material. In some embodiments, the first cathode material can include silicon. In some embodiments, the second cathode material can include graphite.

A bilayer-structured silicon carbon composite anode material, a method of preparing the same, and a secondary battery including the same is provided. The method of preparing the anode material includes: drying a first mixture including graphite balls, a nano-silicon slurry, pitch, and flake graphite to prepare a dried product; sintering the dried product to prepare a sintered product including a hard coating layer formed on an outermost surface thereof and containing amorphous hard carbon; mixing the sintered product with a carbon precursor, followed by heat treatment to form a soft coating layer on an outer circumferential surface of the sintered product; and forming a carbon nanotube layer on an outer circumferential surface of the soft coating layer.

A method for fabricating an electrode for an energy storage device is provided. The method includes heating a mixture of solvent and materials for use as energy storage media; adding active material to the mixture; adding dispersant to the mixture to provide a slurry; coating a current collector with the slurry; and calendering the coating of slurry on the current collector to provide the electrode.

Provided are a binder resin for an electrode of a lithium secondary battery containing a solvent-soluble polyimide having a repeating unit represented by the following Formula [I], and a method of producing the binder resin for an electrode. ##STR00001## (In the formula, Z represents an aromatic or alicyclic tetracarboxylic dianhydride residue, and Ar is an aromatic diamine residue having a carboxyl group and an aromatic diamine residue having an aromatic ether bond, or an aromatic diamine residue having a phenylindan structure).

A porous silicon composite including: a porous silicon composite cluster comprising a porous silicon composite secondary particle and a second carbon flake on at least one surface of the porous silicon composite secondary particle; and a carbonaceous layer on the porous silicon composite cluster, the carbonaceous layer comprising amorphous carbon, wherein the porous silicon composite secondary particle comprises an aggregate of two or more silicon primary particles, the two or more silicon primary particles comprise silicon, a silicon suboxide of the formula SiO.sub.x, wherein 0<x<2 on a surface of the silicon, and a first carbon flake on at least one surface of the silicon suboxide, the silicon suboxide is in a form of a film, a matrix, or a combination thereof, and the first carbon flake and the second carbon flake are each independently present in a form of a film, particles, a matrix, or a combination thereof. Also a method of preparing the porous silicon composite, a carbon composite, an electrode, and a device, each including the porous silicon composite, and a lithium battery including the electrode.

A positive-electrode material for a lithium secondary battery is provided. The material includes a lithium oxide compound or a complex oxide as reactive substance. The material also includes at least one type of carbon material, and optionally a binder. A first type of carbon material is provided as a coating on the reactive substance particles surface. A second type of carbon material is carbon black. And a third type of carbon material is a fibrous carbon material provided as a mixture of at least two types of fibrous carbon material different in fiber diameter and/or fiber length. Also, a method for preparing the material as well as lithium secondary batteries including the material is provided.