Abstract: This application provides a secondary battery, a battery module, a battery pack, and an electrical device. The secondary battery includes a positive electrode plate and an electrolyte solution. The electrolyte solution contains a film-forming additive. A film resistance x? of the positive electrode plate and a mass percent y % of the film-forming additive based on a total mass of the electrolyte solution satisfy: x×y?25. The film resistance and the film-forming additive of the secondary battery provided in this application satisfy the above relationship. Regulating the film resistance and the film-forming additive of the secondary battery as disclosed enhances the Coulombic efficiency, high-temperature cycle performance, and high-temperature storage performance of the battery.

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 relates to a sodium-ion battery and an electrical apparatus including the same. The sodium-ion battery includes a positive electrode sheet, a separator, and a negative electrode current collector, wherein the separator is disposed between the positive electrode sheet and the negative electrode current collector, a surface of the negative electrode current collector is provided with a protective layer capable of allowing sodium-ions to pass freely, a material of the protective layer mainly includes a polymer material, there is an accommodation area between the protective layer and the negative electrode current collector, and the accommodation area has a sodium metal layer formed on the surface of the negative electrode current collector. The sodium-ion battery can effectively improve the inhibition of sodium dendrites, reduce side reactions between sodium metal and an electrolyte solution, and improve the cycle performance of the sodium-ion battery.

Abstract: This application relates to a sodium-ion battery and an electric apparatus containing the same. The sodium-ion battery includes a positive electrode plate, a separator, and a negative electrode current collector. The separator is disposed between the positive electrode plate and the negative electrode current collector. A coating is provided on a surface of the negative electrode current collector, the coating includes a carbon material, and the carbon material includes carbon nanotubes. The sodium-ion battery can effectively enhance the suppression of sodium dendrites and improve the cycling performance. In addition, it is unnecessary to additionally provide a negative electrode active material layer, reducing the costs of the sodium-ion battery and improving the energy density of the sodium-ion battery.

Abstract: This application provides an electrolyte, a sodium-ion battery, a battery module, a battery pack, and an electric apparatus. The electrolyte includes a sodium salt and an organic solvent. The organic solvent includes a fluorinated organic substance, an ether organic substance, and a coordinating organic substance, where the coordinating organic substance includes a plurality of functional groups capable of coordinating with transition metal. The electrolyte provided in this application can improve cycling performance of sodium-ion batteries in high-temperature environments.

Abstract: Provided are a positive electrode material composition, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same. The positive electrode material composition comprises a positive electrode active material with a core-shell structure and an organopolysiloxane compound, wherein said core comprises Li1+xMn1-yAyP1-zRzO4; and said shell comprises a first cladding layer covering said core and a second cladding layer covering said first cladding layer. The positive electrode material composition of the present application enables the secondary battery to have a higher energy density, while having improved cycle performance, safety performance and/or rate performance.

Abstract: This application provides a sodium-ion battery electrolytic solution. The electrolytic solution includes an ether compound as a solvent, a sodium borate compound as a sodium salt, and a borate ester compound as an additive, and a percentage of the ether compound in a total solvent of the electrolytic solution is 50 wt % or above. The electrolytic solution can inhibit battery volume expansion and sodium dendrite growing. This application further provides a sodium-ion battery including the electrolytic solution, a battery module, a battery pack, and an electrical device.

Abstract: The present application provides an electrolyte solution for a sodium-ion battery, comprising a sodium salt of formula NaBOaFxRy?z, a fluoroalkyl ether, and other ethers except for the fluoroalkyl ether, wherein a, x, y, and z are as defined in the specification. The electrolyte solution according to the present application has good stability, particularly oxidation resistance and good solvability of sodium ions, thus broadening an electrochemical window of a corresponding sodium-ion battery, enhancing coulombic efficiency, and improving cycling performance and safety performance. The present application further provides a secondary battery, a battery module, a battery pack, and an electrical apparatus using the electrolyte solution for a sodium-ion battery.

Abstract: Provided are a positive electrode active material, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same. The positive electrode active material has a core-shell structure, comprising a core and a shell cladding the core, wherein the core has a chemical formula of Li1+xMn1-yAyP1-zRzO4, the shell comprises a first cladding layer cladding the core, a second cladding layer cladding the first cladding layer, a third cladding layer cladding the second cladding layer and a fourth cladding layer cladding the third cladding layer. The positive electrode active material of the present application enables the secondary battery to have a relatively high energy density, and good cycling performance, rate performance and safety performance.

Abstract: The present application provide a silicon-oxygen compound, a preparation method thereof and related secondary battery, battery module, battery pack, and device. 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 manganese element, and the sulfur element is present in an amount of 20 ppm˜300 ppm. The mass ratio of sulfur element to manganese element is from 1.5 to 10.

Abstract: The present application discloses a composite graphite material and a method for preparing the same, a secondary battery, and an apparatus. The composite graphite material includes a core material and a coating layer that coats at least a portion of the surface of the core material, the core material including graphite, and the coating layer including a coating material containing a cyclic structure moiety, wherein the composite graphite material has a weight-loss rate of from 0.1% to 0.55% when the composite graphite material is heated in an atmosphere of an inert non-oxidative gas at a temperature rising from 40° C. to 800° C. The composite graphite material can enhance the gram capability and reduce the expansion rate of an electrode plate, and more preferably, can improve the cycle performance and kinetic performance of a battery as well.

Abstract: Provided are a positive electrode material composition, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same. The positive electrode material composition comprises a positive electrode active material with a core-shell structure and an organopolysiloxane compound, wherein the positive electrode active material comprises a core and a shell covering the core, wherein the core has a chemical formula of Li1+xMn1?yAyP1?zRzO4, and the shell comprises a first cladding layer covering the core, a second cladding layer covering the first cladding layer, and a third cladding layer covering the second cladding layer. The positive electrode material composition of the present application enables the secondary battery to have a relatively high energy density, while further improving cycling performance safety performance and/or rate performance of the secondary battery.

Abstract: The present application provides a positive electrode material composition, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same. The positive electrode material composition includes a positive electrode active material and an organopolysiloxane compound, wherein said positive electrode active material has a chemical formula of LiaAxMn1-yByP1-zCzO4-nDn. The positive electrode material composition of the present application enables the secondary battery to have a relatively high energy density, while further improving rate performance, cycling performance and/or high-temperature stability of the secondary battery.

Abstract: Provided are a positive electrode active material, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same. The positive electrode active material has a core-shell structure, including a core and a shell cladding the core, wherein the core includes Li1+xMn1?yAyP1?zRzO4, the shell includes a first cladding layer cladding the core, a second cladding layer cladding the first cladding layer and a third cladding layer cladding the second cladding layer. The positive electrode active material of the present application enables the secondary battery to have a relatively high energy density, and good rate performance, cycling performance and safety performance.

Abstract: A positive electrode active material, a method for preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same are provided. The positive electrode active material has a core-shell structure, comprising a core, a first cladding layer covering the core, a second cladding layer covering the first cladding layer, wherein the core has a chemical formula of LiaAxMn1-yByP1-zCzO4-nDn, the first cladding layer comprises a first polymer containing an electron withdrawing group, the second cladding layer comprises a second polymer, and wherein the second polymer comprises one or more of plant polysaccharides, marine polysaccharides and the derivatives thereof. The positive electrode active material of the present application enables a secondary battery to have a relatively high energy density, while further having a significantly improved rate performance, cycling performance and/or high-temperature stability.

Abstract: Provided are a positive electrode active material, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same. The positive electrode active material has a core-shell structure, comprising a core and a shell cladding the core, wherein the core has a chemical formula of Li1+xMn1-yAyP1-zRzO4, the shell comprises a first cladding layer cladding the core, a second cladding layer cladding the first cladding layer, a third cladding layer cladding the second cladding layer and a fourth cladding layer cladding the third cladding layer. The positive electrode active material of the present application enables the secondary battery to have a relatively high energy density, and good cycling performance, rate performance and safety performance.

Abstract: A positive electrode active material, a method for preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same are provided. The positive electrode active material has a core-shell structure, comprising a core, a first cladding layer covering the core, a second cladding layer covering the first cladding layer, wherein the core has a chemical formula of LiaAxMn1-yByP1-zCzO4-nDn, the first cladding layer comprises a first polymer containing an electron withdrawing group, the second cladding layer comprises a second polymer, and wherein the second polymer comprises one or more of plant polysaccharides, marine polysaccharides and the derivatives thereof. The positive electrode active material of the present application enables a secondary battery to have a relatively high energy density, while further having a significantly improved rate performance, cycling performance and/or high-temperature stability.

Abstract: A positive electrode active material, a method for the preparation thereof and a positive electrode plate, a secondary battery and an electrical device containing the same are provided. The positive electrode active material has a core-shell structure, comprising a core and a cladding layer covering at least a portion of said core, wherein said core has a chemical formula of LiaAxMn1-yByP1-zCzO4-nDn, said cladding layer comprises a polymer containing an electron withdrawing group. The positive electrode active material of the present application enables a secondary battery to have a relatively high energy density, while further having a significantly improved rate performance, cycling performance and/or high-temperature stability.

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.