Abstract: This application provides a silicon-based negative electrode active material. The silicon-based negative electrode active material includes a silicate containing an alkali metal element. The silicon-based negative electrode active material contains both element S and element Mg.

Abstract: This application provides a secondary battery and an electric apparatus. The secondary battery includes a negative electrode plate. The negative electrode plate includes a negative electrode current collector, and a negative electrode film layer that is provided on at least one surface of the negative electrode current collector and includes a negative electrode active material. The negative electrode active material includes a carbon-based material and a silicon-based material. The carbon-based material includes secondary particles formed by aggregation of primary particles. The silicon-based material includes secondary particles formed by aggregation of primary particles.

Abstract: A secondary battery and an electric apparatus are disclosed. The secondary battery includes a negative electrode plate including a negative electrode current collector and a negative electrode film layer with a thickness of H; a first surface away from the negative electrode current collector; and a second surface opposite the first surface. A first region of the negative electrode film layer includes a first active material with a thickness range from the second surface of the negative electrode film layer to 0.3H. The first active material includes a first carbon-based material and a first silicon-based material. The first carbon-based material includes primary particles. The first silicon-based material includes secondary particles formed by aggregating the primary particles. A second region of the negative electrode film layer includes a second active material and has a thickness range from the first surface of the negative electrode film layer to 0.3H.

Abstract: A silicon carbon negative material is provided. The silicon carbon negative material includes a porous carbon base, nano-silicon crystal grains located in pores of the porous carbon base, and a carbon coating layer located on a surface of the porous carbon base. The nano-silicon crystal grains include an elemental silicon core and a LixSiy coating layer, x is an integer selected from 7 to 22, and y is an integer selected from 3 to 7.

Abstract: This application relates to a silicon-carbon composite material. The silicon-carbon composite material includes a carbon nanotube-and-porous carbon composite substrate and a silicon-based material. The porous carbon is connected to the carbon nanotube by a connecting unit in the carbon nanotube-and-porous carbon composite substrate. The high conductivity and strong mechanical properties of the carbon nanotubes can improve the overall conductivity, compression resistance, and expansion resistance of the silicon-carbon composite material, thereby improving cycle performance, electrode plate cycle expansion resistance, and rate performance of a secondary battery.

Abstract: Provided are a negative electrode active material and a preparation method thereof, a secondary battery, and an electric apparatus. The negative electrode active material includes: a core material; and a first coating layer provided on at least part of a surface of the core material, where the first coating layer includes a porous carbon material and nano silicon-based particles, and the nano silicon-based particles are embedded into pore structures of the porous carbon material.

Abstract: The present application provides a negative electrode active material, a secondary battery comprising the same and an electrical device, wherein the negative electrode active material comprises a matrix material and a silicon-based material, the matrix material comprises a plurality of pore structures, at least a part of the silicon-based material is located in pore structures of the matrix material, at least a part of the silicon-based material has a crystalline structure, the silicon-based material comprises a first silicon-based material and a second silicon-based material with different grain sizes, and a ratio of grain size of the first silicon-based material to grain size of the second silicon-based material is greater than or equal to 1.6. The negative electrode active material can result in a secondary battery having high energy density, high First Coulombic Efficiency, long cycle life and long storage life at the same time.

Abstract: The present application provides a negative electrode active material, a secondary battery comprising the same and an electrical device, wherein the negative electrode active material comprises a matrix material and a silicon-based material, the matrix material comprises a plurality of pore structures, at least a part of the silicon-based material is located in pore structures of the matrix material, the silicon-based material comprises a crystalline silicon-based material, a region formed by extending from outer surface of particle of the negative electrode active material to inside of the particle by a distance of 0.5 times a length between any point on the outer surface of the particle of the negative electrode active material and a core of the particle is recorded as an outer region, and a region inside the outer region is recorded as an inner region.

Abstract: A negative electrode active material includes a carbon-silicon composite, which includes a carbon-based particle and a silicon nanoparticle. The carbon-based particle has a carbon skeleton. The silicon nanoparticle is attach to the carbon skeleton of carbon-based particle. In a peripheral area of the carbon-silicon composite, a mass percentage content A1 of carbon element and a mass percentage content B1 of silicon element satisfy 0.8?B1/A1?2.5.