Abstract: A negative electrode active material includes a silicon-carbon composite, where the silicon-carbon composite includes a silicon oxide and graphite, a general formula of the silicon oxide is SiOx, 0.5?x?1.6, and the silicon-carbon composite satisfies the following relation: 2?b/a<6, wherein a represents an average particle size of the silicon oxide, and b represents an average particle size of graphite. The negative electrode active material as a negative electrode active material of a lithium-ion battery can prolong cycle life and enhance cycling structure stability.

Abstract: A packaging film including a protective layer, a first bonding layer, a metal layer. a second bonding layer and a sealing layer. The protective layer, the first bonding layer, the metal layer. the second bonding layer, and the sealing layer are sequentially stacked. The protective layer includes a polymer resin layer and a carbon material.

Abstract: A negative electrode material includes a silicon-based material, where a particle of the silicon-based material includes at least one recessed portion, and the recessed portion is 50 nm to 20 ?m in width, and 50 nm to 10 ?m in depth. The recessed structure leaves room for the silicon-based material to swell, thereby solving the problem of large volume swelling of the silicon-based material. In addition, when the silicon-based material with the recessed structure is composited with a carbon material, a conductive agent, and the like to form a negative electrode plate, small particles of the carbon material and the conductive agent are embedded into the recessed portion of the silicon-based material, solving the problem of low compacted density of the silicon-based negative electrode material with a recessed structure, and compensating for the low volumetric energy density of the recessed structure.