The present application relates to a secondary battery, comprising: a positive electrode plate, a negative electrode plate, a separator disposed between the positive electrode plate and the negative electrode plate, and an electrolyte solution, the negative electrode plate including a negative electrode current collector and a negative electrode active material layer provided on at least one side of the negative electrode current collector, and the electrolyte solution including an organic solvent and a lithium salt, wherein the negative electrode active material comprises a core structure and a polymer network coating layer coated on at least a part of the surface of the core structure.