The disclosure relates to a method for preparing a 3D sponge structured carbonitride coated VSe.sub.2 composite (3D-VSe.sub.2@CN), belonging to the technical fields of electrode materials and preparation of batteries. In the disclosure, carbon, nitrogen and VSe.sub.2 are composited by using NaCl as a template so as to construct a 3D sponge structured carbonitride coated VSe.sub.2 composite. The 3D sponge structure can increase the structure stability of the material in the cyclic process, and the carbocanitride can increase the electron conductivity and activity sites of the material, so as to allow easier diffusion of potassium ions. Meanwhile, the stable structure can cause the clustering of VSe.sub.2 all the time. Thus, the prepared composite has good and stable rate capability and cycle stability. The process method is simple, low in cost, environmental-friendly, and suitable for large-scale industrial production.

A method for manufacturing a lithium secondary battery, including the steps: (S1) forming a preliminary negative electrode by coating a negative electrode slurry including a negative electrode active material, conductive material, binder and a solvent onto at least one surface of a current collector, followed by drying and pressing the negative electrode slurry coated current collector, to form a negative electrode active material layer surface on the current collector; (S2) coating lithium metal foil onto the negative electrode active material layer surface of the preliminary negative electrode in the shape of a pattern in which pattern units are arranged; (S3) cutting the preliminary negative electrode on which the lithium metal foil is pattern-coated to obtain negative electrode units; (S4) impregnating the negative electrode units with an electrolyte to obtain a pre-lithiated negative electrode; and (S5) assembling the negative electrode obtained from step (S4) with a positive electrode and a separator.

The present application provides a silicon-oxygen composite negative electrode material and a preparation method therefor, and a lithium ion battery. The silicon-oxygen composite negative electrode material has a core-shell structure, the core comprises nano-silicon and a silicon oxide SiO.sub.x, and the shell comprises Li.sub.2SiO.sub.3. The preparation method comprises: mixing a silicon source and a lithium source, and performing heat treatment in a non-oxygen atmosphere to obtain a composite material containing Li.sub.2SiO.sub.3; and immersing the composite material containing Li.sub.2SiO.sub.3 in an acid solution to obtain the silicon-oxygen composite negative electrode material. The nano-silicon in the negative electrode material provided by the present application is wrapped by SiO.sub.x, and the surface of SiO.sub.x is further wrapped with the Li.sub.2SiO.sub.3 having a stable structure, making it difficult for the nano-silicon to come into physical contact with substances other than the SiO.sub.x and impossible to come into direct contact with water, thereby effectively inhibiting gas production of a battery.

A non-aqueous electrolyte secondary battery disclosed herein includes a positive electrode, a negative electrode, and a non-aqueous electrolyte. The positive electrode includes a positive electrode current collector, and a positive electrode active material layer, an insulating layer, and a boundary layer which are provided on the positive electrode current collector. The boundary layer is positioned between the positive electrode active material layer and the insulating layer, and is in contact with the positive electrode active material layer and the insulating layer. The positive electrode active material layer contains a positive electrode active material. The insulating layer contains an inorganic filler. The boundary layer contains the positive electrode active material contained in the positive electrode active material layer and the inorganic filler contained in the insulating layer. The boundary layer contains hydrated alumina. The non-aqueous electrolyte contains lithium fluorosulfonate.

A composite for use the manufacture of an electrode, the composition comprising a spontaneously formed segregated network of nanosheets of conducting materials, or a combination thereof, and a particulate active material, in which no additional polymeric binder or conductive-additive are required.

An electrochemical cell is provided, which includes a cathode comprising a three dimensional (3D) porous cathode structure, an anode, an electrolyte separator, comprised of a ceramic material, located between the cathode and the anode, and a cathode current collector, wherein the cathode is located between the cathode current collector and the electrolyte separator. The 3D porous cathode structure includes ionically conducting electrolyte strands extending through the cathode from the cathode current collector to the electrolyte separator, pores extending through the cathode from the cathode current collector to the electrolyte separator, and an electronically conducting network extending on sidewall surfaces of the pores from the cathode current collector to the electrolyte separator.

The present disclosure provides a current collector of a secondary battery in which the current inside the battery is easily blocked at the time of inside short circuit, and in which the capacity retention rate and the decreasing rate of the electric resistance are outstanding. The current collector herein disclosed includes a laminate structure in which a resin layer and a metal layers formed on the both surfaces of the resin layer are laminated. The surface of the metal layer includes a rough surface part provided with a plurality of protruding parts and a plurality of recessed parts. On the rough surface part, a resin coat layer is formed, and at least one part of the protruding part among the plurality of protruding parts includes an exposed part that is exposed from the resin coat layer.

A separator for a rechargeable battery includes a porous substrate and a heat resistance layer on at least one surface of the porous substrate. The heat resistance layer includes an acryl-based copolymer, an alkali metal, and a filler. The acryl-based copolymer includes a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and a sulfonate group-containing unit.

The present disclosure provides an electrochemical cell that includes a double-sided electrode. The double-sided electrode includes a first electroactive material layer, a second electroactive material layer, and a current collector disposed between the first and second electroactive material layers. Each of the first and second electroactive material layers may include a plurality of electroactive material sub-films and a plurality of buffer layers disposed between adjacent electroactive material sub-films. The electrochemical cell further includes a first single-sided electrode substantially aligned with the first electroactive material layer; a first separator physically separating the first single-sided electrode and the first electroactive material layer; a second single-sided electrode substantially aligned with the second electroactive material layer; and a second separator physically separating the second single-sided electrode and the second electroactive material layer. The current collector may include at least one surface coated with an adhesive layer.

Provided herein is a method of preparing anode slurries of lithium-ion batteries. The silicon-based material is uniformly dispersed prior to mixing with other components of the anode slurry. The method disclosed herein is capable of avoiding agglomeration of nano-sized silicon-based material and effectively dispersing the nano-sized silicon-based material uniformly in anode slurries. Anodes coated with the anode slurries disclosed herein also show an improvement in the electrical conductivity.