Negative electrode of secondary battery, manufacturing method of negative electrode, and secondary battery with negative electrode

A manufacturing method of a negative electrode of a secondary battery, comprising:

• a step for preparing first Si-containing particles and second Si-containing particles, as a negative electrode active material;
• a step for mixing the first Si-containing particles and the second Si-containing particles in a dispersion medium and for preparing a negative electrode paste;
• a step for applying the negative electrode paste to coat the negative electrode current collector;
• and
• a step for drying the coating negative electrode paste, wherein
• an expansion rate S1 of the first Si-containing particles after an electrical charge A with respect to before the electrical charge A, in which a constant current electrical charge is performed under 25° C. environment by a current value being 0.01 C till 4.2 V and then a constant voltage electrical charge is performed till the current value reaches 0.005 C, is more than 0.3 and not more than 0.9 when an expansion rate S2 of the second Si-containing particles after the electrical charge A with respect to before the electrical charge A is treated as 1,
• each of the first Si-containing particles and the second Si-containing particles comprises a LiF coating layer, and
• when a ratio of a peak intensity of a F of a LiF with respect to a peak intensity of the F of one being other than the LiF on a XPS spectrum of the first Si-containing particles measured by a X-ray photoelectron spectroscopy is treated as a first peak intensity ratio and the ratio of the peak intensity of the F of the LiF with respect to the peak intensity of the F of one being other than the LiF on a XPS spectrum of the second Si-containing particles is treated as a second peak intensity ratio, the second peak intensity ratio is larger than the first peak intensity ratio.