Secondary battery, preparation method thereof and electric equipment

The invention provides a secondary battery, a preparation method thereof and electric equipment, and belongs to the technical field of lithium ion batteries. The secondary battery comprises a positive pole piece and a negative pole piece, the positive pole piece comprises a positive pole active material, the negative pole piece comprises a negative pole active material, and fluorine is doped in the positive pole active material and the negative pole active material, so that the charge distribution on the surface and in the active material can be improved, and relatively strong electronegativity is formed around the fluorine; the position far away from the fluorine element has relatively strong electropositivity, so that a charge network is formed inside and on the surface of the active material. At low temperature, the charge network can reduce interface charge transfer impedance and solid-phase diffusion impedance of lithium ions and electrons on the surface and in the active material, so that the low-temper