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 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: 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 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 provides a negative electrode active material, a process for preparing the same, and a secondary battery, a battery module, a battery pack and an apparatus related the same. The negative electrode active material comprises a core material and a polymer-modified coating layer on at least a part of a surface of the core material, the core material is one or more of a silicon-based negative electrode material and a tin-based negative electrode material, the polymer-modified coating layer comprises sulfur element and carbon element, the sulfur element has a mass percentage of from 0.2% to 4% in the negative electrode active material, the carbon element has a mass percentage of from 0.5% to 4% in the negative electrode active material, and the polymer-modified coating layer comprises a —S—C— bond.

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: 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 structure and a modified polymer coating layer coated on at least a part of the outer surface of the core structure, wherein the core structure comprises one or more of silicon-based materials and tin based materials; and wherein the negative active material has an infrared spectrum comprising an infrared absorption peak at the wavelength of 1450 cm?1 to 1690 cm?1, and the infrared absorption peak has a transmittance T that satisfies 80%?T?99%.

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 secondary battery and related battery module, battery pack and apparatus. The secondary battery includes a positive electrode plate, a negative electrode plate, a separator and an electrolyte, wherein the secondary battery includes a positive active material selected from one or more of layered lithium nickel cobalt manganese oxide and layered lithium nickel cobalt aluminum oxide, and a negative active material including graphite and silicon-oxygen compound; the delithiation capacity A of the negative electrode film in the voltage range of 0.005V to the delithiation platform voltage and the delithiation capacity B of the negative electrode film in the voltage range of the delithiation platform voltage to 1.2V satisfy: 1A/B2; and when the secondary battery is discharged to a voltage of 2.5V, the voltage U of the negative electrode plate relative to a lithium metal reference electrode satisfies: 0.5VU0.7V.

Abstract: The present application provides a negative electrode active material, a process, a battery, a battery module, a battery pack and an apparatus related to the same. The negative electrode active material comprises a core material and a polymer modified coating on at least a part of a surface of core material; wherein the core material is one or more of a silicon-based negative electrode material and a tin-based negative electrode material; the negative electrode active material has a weight loss rate satisfying 0.2%?weight loss rate?2% in a thermogravimetric analysis test wherein temperature is elevated from 25° C. to 800° C. under a non-oxidizing inert gas atmosphere. The present application can reduce damage to the surface structure of the negative electrode active material, reduce loss of active ions and capacity, meanwhile can well improve coulomb efficiency and cycle performance of the battery.

Abstract: Positive current collector, positive plate, electrochemical device and apparatus are disclosed. The positive current collector includes a support layer and a metal conductive layer disposed on the support layer, where a ratio of a density of the metal conductive layer to an intrinsic density of a material of the metal conductive layer is greater than or equal to 0.89, and the material of the metal conductive layer is selected from one or more of aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy. The positive current collector can provide simultaneously both low weight and high electrical performance, thus enabling the electrochemical device to achieve both high weight energy density and electrochemical performance at the same 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. 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 discloses a negative electrode current collector, a negative electrode plate and an electrochemical device. The negative electrode current collector includes an organic support layer and a copper-based conductive layer disposed on at least one surface of the organic support layer; and a copper-based crystal grain size in the copper-based conductive layer is from 10 nm to 500 nm. The negative electrode current collector provided by the present application has good mechanics properties while having less weight and good electrical conductivity and current collection performance, which can improve preparation yields of the negative electrode current collector, the negative electrode plate and the electrochemical device and their safety and reliability during use, and enables the electrochemical device to have relatively high gravimetric energy density and good electrochemical performance.

Abstract: The present application discloses a positive electrode current collector, a positive electrode plate, an electrochemical device, and an apparatus. The positive electrode current collector includes a polymer material-based support layer and an aluminum-based conductive layer disposed on at least one surface of the support layer; a thickness D1 of the aluminum-based conductive layer, a tensile strength T of the support layer, and a thickness D2 of the support layer satisfy a relational formula 0.01?(200×D1)/(T×D2)?0.5, in the formula D1 and D2 are in the same unit, and T is in MPa. The positive electrode current collector has relatively high mechanics and mechanical properties, good electrical conductivity and current collection performance and low weight, which can improve preparation yield of the positive electrode current collector, the positive electrode plate and the electrochemical device and their reliability during use.