ELECTROCHEMICAL DEVICE AND ELECTRONIC DEVICE

This application provides an electrochemical device and an electronic device. The electrochemical device includes a positive electrode plate, a negative electrode plate, and an electrolyte solution. The negative electrode plate includes a negative current collector and a negative electrode material layer. The negative electrode material layer includes a silicon-based composite material. The silicon-based composite material includes a silicon-based particle. Strength of the negative current collector is A MPa. A difference between a maximum value and a minimum value of a relative mass percent of silicon atoms in the silicon-based particle is B%, and a mass percent of silicon in the negative electrode material layer is C%, satisfying: A≥10B+250C1/4+110/C.By synergistically adjusting A, B, and C to meet the above conditions, this application achieves a lithium-ion battery of good cycle performance and expansion resistance.