| abstract |
The invention belongs to the technical field of energy storage, and specifically discloses a negative electrode active material, which comprises SiO x particles and a modified polymer coating layer covering the SiO x particles, wherein 0<x<2; the negative electrode active material The intensity of the peak in the range of the Raman shift of 280 cm- 1 to 345 cm -1 is I 1 , the intensity of the peak of the negative electrode active material in the range of the Raman shift of 450 cm -1 to 530 cm- 1 is I 2 , and the negative electrode has an intensity of I 2 . The peak intensity of the active material in the Raman shift range of 900 cm -1 to 960 cm -1 is I 3 , and 0.1≤I 1 /I 2 ≤0.6, 0.2≤I 3 /I 2 ≤1.0. The invention also discloses a method for preparing the negative electrode active material and a secondary battery. The use of the negative electrode active material of the present invention can improve the cycle performance of the secondary battery and increase the energy density of the secondary battery. |