Abstract: A positive electrode current collector, a positive electrode piece, an electrochemical device and an apparatus, where the positive electrode current collector includes a support layer and a conductive layer provided on the support layer, where a material of the conductive layer is aluminum or aluminum alloy, and a thickness D1 of the conductive layer is 300 nm?D1?2 ?m; an elongation at break B of the support layer is 10,000%?B?12%, and a volume resistivity of the support layer is greater than or equal to 1.0×10?5 ?·m; when a tensile strain of the positive electrode current collector is 2%, a square resistance growth rate T1 of the conductive layer is T1?10%. The positive electrode current collector provided in the present application can simultaneously take into account both high safety performance and electrical performance.

Abstract: The present disclosure provides a lithium ion secondary battery, a battery core, a negative electrode plate and an apparatus containing the lithium ion secondary battery. The lithium ion secondary battery includes a battery core and an electrolytic solution, the battery core including a positive electrode plate comprising a positive current collector and a positive active material layer, a separator, and a negative electrode plate comprising a negative current collector and a negative active material layer, wherein the positive current collector and/or the negative current collector are a composite current collector, the composite current collector comprises a polymer-based support layer and a conductive layer disposed on at least one surface of the support layer, and the composite current collector has a thermal conductivity in a range of 0.01 W/(m·K) to 10 W/(m·K), preferably in a range of 0.1 W/(m·K) to 2 W/(m·K).

Abstract: The present application provides a high-nickel ternary positive electrode active material, which comprises a core Li1+a[LixCoyMnzMb]O2, a fast ionic conductor Li?AlXSiYO4 of a first shell layer, an oxide of an element R of a second shell layer, and a transition layer LipRqOw formed between the first shell layer and the second shell layer. In the high-nickel ternary positive electrode active material of the present application, the surface impurity lithium amount is significantly reduced, and by creatively converting the surface impurity lithium into effective components in the fast ionic conductors Li?AlXSiYO4 and LipRqOw which accelerate the intercalation/deintercalation of lithium ions in the core material, the decomposition and gas production of an electrolyte solution caused by the surface impurity lithium is greatly improved, such that a high-nickel ternary lithium-ion battery has high energy density as well as good cycle performance and safety performance.

Abstract: A positive electrode current collector and a positive electrode plate, a battery, a battery module, a battery pack, and an apparatus including the positive electrode current collector are provided. In some embodiments, a positive electrode current collector is provided, including an organic support layer and an aluminum-based conductive layer disposed on at least one surface of the organic support layer, where the aluminum-based conductive layer contains Al and at least one modifying element selected from O, N, F, B, S, and P, an XPS spectrogram of the aluminum-based conductive layer with a surface passivation layer removed through etching has at least a first peak falling in a range of 70 eV to 73.5 eV and a second peak falling in a range of 73.5 eV to 78 eV, and a ratio x of peak intensity of the second peak to that of the first peak satisfies 0<x?3.0.

Abstract: The invention refers to negative electrode plate, preparation method thereof and electrochemical device. The negative electrode plate comprises: a negative current collector, a negative active material layer, and an inorganic dielectric layer which are provided in a stacked manner; the negative active material layer comprises opposite first surface and second surface, wherein the first surface is disposed away from the negative current collector; the inorganic dielectric layer is disposed on the first surface of the negative active material layer and consists of an inorganic dielectric material. The negative electrode plate provided by the application is useful in an electrochemical device, and can result in an electrochemical device having simultaneously excellent safety performance and cycle performance.

Abstract: Provided are a current collector, an electrode plate, a battery and an application of the current collector. The current collector includes an insulation layer and a conductive layer. The insulation layer is configured to bear the conductive layer, the conductive layer is configured to bear an electrode active material layer. A room temperature film resistance RS of the conductive layer meets a conditional expression: 0.016?/??RS?420?/?. By the current collector of the present application, the short circuit resistance of the battery in case of an abnormal situation causing the short circuit can be greatly increased, and the short circuit current can be greatly reduced. Thus, influence of the short circuit damage on the battery is limited to a point range, and an interrupt in the current only occurs in a point range, without disrupting normal operation of the battery in a certain period time.

Abstract: The invention refers to negative electrode plate, preparation method thereof and electrochemical device. The negative electrode plate comprises: a negative current collector, a negative active material layer, and an inorganic dielectric layer which are provided in a stacked manner; the negative active material layer comprises opposite first surface and second surface, wherein the first surface is disposed away from the negative current collector; the inorganic dielectric layer is disposed on the first surface of the negative active material layer and consists of an inorganic dielectric material. The negative electrode plate provided by the application is useful in an electrochemical device, and can result in an electrochemical device having simultaneously excellent safety performance and cycle performance.

Abstract: The present application provide a silicon-oxygen compound, a secondary battery using it, and related battery modules, battery packs, and devices. The silicon-oxygen compound provided by the present application has a formula of SiOx, in which x satisfies 0<x<2. The silicon-oxygen compound contains both sulfur and aluminum element, and the sulfur element is present in an amount of 20 ppm˜300 ppm. The mass ratio of sulfur element to aluminum element is from 1.5 to 13.0. A secondary battery uses the silicon-oxygen compound provided in the present application, so that the secondary battery can have both long-cycle performance and high initial coulombic efficiency.

Abstract: This application provides a silicon-based material, a preparation method thereof, and a secondary battery, a battery module, a battery pack, and an apparatus associated therewith. The silicon-based material includes a core structure and a coating layer provided on at least partial surface of the core structure, where the core structure includes both a silicon phase and a lithium metasilicate phase, and a particle size P of the lithium metasilicate phase is ?30 nm. The silicon-based material of this application can not only increase energy density of a secondary battery with the silicon phase, but also improve structural stability and chemical stability of the silicon-based material, so that the secondary battery can deliver satisfactory and balanced cycling performance and first-cycle coulombic efficiency in overall.

Abstract: The present application discloses a negative active material, a method for preparing the same, and related secondary batteries, battery modules, battery packs and apparatus. The negative active material includes a core material and a polymer-modified coating layer on at least a part of its surface; the core material includes one or more of silicon-based materials and tin-based materials; the coating layer includes sulfur element and carbon element; in the Raman spectrum of the negative active material, the negative active material has scattering peaks at the Raman shifts of 900 cm?1˜960 cm?1, 1300 cm?1˜1380 cm?1 and 1520 cm?1˜1590 cm?1, respectively, in which the scattering peak at the Raman shift of 900 cm?1˜960 cm?1 has a peak intensity recorded as Il, the scattering peak at the Raman shift of 1520 cm?1˜1590 cm?1 has a peak intensity recorded as IG, and Il and IG satisfy 0.2?Il/IG?0.8.

Abstract: The present disclosure provides a negative current collector (10), a negative electrode plate (20), an electrochemical device, and an apparatus. The negative current collector (10) includes a support layer, and a conductive layer (102) disposed on at least one of two opposite surfaces of the support layer (101) in a thickness direction of the support layer; wherein the support layer (101) has a smaller density than the conductive layer (102); the conductive layer (102) has a thickness D1 satisfying 300 nm?D1?2 ?m, preferably 500 nm?D1?1.5 ?m; and when the negative current collector (10) has a tensile strain of 1.5%, the conductive layer (102) has a sheet resistance growth rate T satisfying T?5%.

Abstract: This application belongs to the field of energy storage technology, and specifically discloses a negative active material including SiOx particles and a modified polymer coating layer covering the SiOx particles, in which 0<x<2; wherein the negative active material has a peak intensity I1 at the Raman shift ranging from 280 cm?1 to 345 cm?1, a peak intensity 12 at the Raman shift ranging from 450 cm?1 to 530 cm?1, and a peak intensity 13 at the Raman shift ranging from 900 cm?1 to 960 cm?1, and I1, I2 and I3 satisfy 0.1?I1/I2?0.6, and 0.2?I3/I2?1.0. This application also discloses a method for preparing a negative active material and related secondary batteries, battery modules, battery packs and apparatus.

Abstract: The present disclosure relates to the technical field of energy storage, and in particular, relates to a positive electrode, a method for preparing the positive electrode and an electrochemical device. The positive electrode includes a current collector and a positive electrode active material layer that contains positive electrode active material and is arranged on at least one surface of the current collector. An inorganic layer having a thickness of 20 nm to 2000 nm is arranged on the surface of the at least one positive electrode active material layer away from the current collector. The inorganic layer is a porous dielectric layer containing no binder, and the inorganic layer has a porosity of 10%˜60%. The positive electrode active material layer according to the present disclosure significantly improves the cycle performance, high-temperature storage performance and safety of the electrochemical device.

Abstract: The present application discloses a negative active material, a method for preparing the same, and related secondary batteries, battery modules, battery packs and apparatus. The negative active material includes a core material and a polymer-modified coating layer on at least a part of its surface; the core material includes one or more of silicon-based materials and tin-based materials; the coating layer includes sulfur element and carbon element; in the Raman spectrum of the negative active material, the negative active material has scattering peaks at the Raman shifts of 900 cm?1˜960 cm?1, 1300 cm?1˜1380 cm?1 and 1520 cm?1˜1590 cm?1, respectively, in which the scattering peak at the Raman shift of 900 cm?1˜960 cm?1 has a peak intensity recorded as Il, the scattering peak at the Raman shift of 1520 cm?1˜1590 cm?1 has a peak intensity recorded as IG, and Il and IG satisfy 0.2?Il/IG?0.8.

Abstract: This application relates to a negative electrode plate, a secondary battery and apparatus thereof. The secondary battery of the present application comprises a negative electrode plate, the negative electrode plate comprises a composite current collector and a negative electrode active material layer disposed on at least one surface of the composite current collector, the negative electrode active material layer comprises a silicon-based active material, the silicon-based active material accounts for 0.5 wt % to 50 wt % of total mass of the negative electrode active material layer, and the composite current collector comprises a polymer support layer and a metal conductive layer disposed on at least one surface of the polymer support layer, and the composite current collector has a brittleness parameter C ranging from 0.03 to 0.5. The secondary battery and the negative electrode plate achieve good coordination between the current collector and the negative electrode active material layer.

Abstract: The present disclosure relates to the technical field of energy storage, and in particular, relates to a positive electrode, a method for preparing the positive electrode and an electrochemical device. The positive electrode includes a current collector and a positive electrode active material layer that contains positive electrode active material and is arranged on at least one surface of the current collector. An inorganic layer having a thickness of 20 nm to 2000 nm is arranged on the surface of the at least one positive electrode active material layer away from the current collector. The inorganic layer is a porous dielectric layer containing no binder, and the inorganic layer has a porosity of 10%˜60%. The positive electrode active material layer according to the present disclosure significantly improves the cycle performance, high-temperature storage performance and safety of the electrochemical device.

Abstract: This application belongs to the field of energy storage technology, and specifically discloses a negative active material including SiOx particles and a modified polymer coating layer covering the SiOx particles, in which 0<x<2; wherein the negative active material has a peak intensity I1 at the Raman shift ranging from 280 cm?1 to 345 cm?1, a peak intensity 12 at the Raman shift ranging from 450 cm?1 to 530 cm?1, and a peak intensity 13 at the Raman shift ranging from 900 cm?1 to 960 cm?1, and I1, I2 and I3 satisfy 0.1?I1/I2?0.6, and 0.2?I3/I2?1.0. This application also discloses a method for preparing a negative active material and related secondary batteries, battery modules, battery packs and apparatus.

Abstract: The present application discloses a silicon-oxygen compound, a method for preparation thereof, and a secondary battery, a battery module, a battery pack and an apparatus related thereto. The silicon-oxygen compound includes both manganese element and a copper element, a content of the manganese element is from 20 ppm to 500 ppm, and a mass ratio of the manganese element to the copper element is from 1 to 18.

Abstract: The present application discloses a negative active material, preparation process thereof and a secondary battery and the related battery module, battery pack and device. The negative active material comprises a core material and a modified polymer coating layer coated on at least a part of the outer surface of the core material, the core material comprises one or more of silicon-based materials and tin based materials, the coating layer comprises carbon element and nitrogen element, wherein the nitrogen element is present in the negative active material in a mass percentage of 0.1%˜0.66%, and the coating layer comprises a —C?N-linkage.

Abstract: The present application provide a silicon-oxygen compound, a secondary battery using it, and related battery modules, battery packs, and devices. The silicon-oxygen compound provided by the present application has a formula of SiOx, in which x satisfies 0<x<2. The silicon-oxygen compound contains both sulfur and aluminum element, and the sulfur element is present in an amount of 20 ppm˜300 ppm. The mass ratio of sulfur element to aluminum element is from 1.5 to 13.0. A secondary battery uses the silicon-oxygen compound provided in the present application, so that the secondary battery can have both long-cycle performance and high initial coulombic efficiency.