SECONDARY BATTERY AND MANUFACTURING METHOD THEREFOR, AND ELECTRICAL APPARATUS

A secondary battery comprises a positive electrode plate and a negative electrode plate. The negative electrode plate comprises a negative electrode active material layer. The negative electrode active material layer comprises a negative electrode active material. The negative electrode active material comprises a silicon-based material. In the same charging and discharging cycle process, the volume ratio of the negative electrode plate during charging and discharging of the secondary battery is R, wherein R is less than or equal to 1.5; and the volume ratio of the positive electrode plate during charging and discharging of the secondary battery is Y, wherein Y is less than or equal to 0.98.