The application provides a top cover, a cap
assembly and a battery. The top cover comprises a supporting outer ring, a plurality of
gable connecting pieces and an outer connecting
welding piece connected in sequence, the number of the
gable connecting pieces is at least two, and a pressure relief channel for pressure relief is formed between each two adjacent
gable connecting pieces; a plane where the supporting outer ring is located is defined as a gable
reference plane, each gable connecting piece comprises a vertical extension part and a gable extension part, the gable extension part is connected to the vertical extension part and the outer connecting
welding piece respectively, one end of the vertical extension part away from the gable extension part is connected to the supporting outer ring, a gable is formed between the surface extension direction of the end of the vertical extension part connected to the gable extension part and the gable
reference plane, the degree of the gable is 40°-79°, the inclination angle of each gable connecting piece relative to the supporting outer ring is large, the top cover has good compression deformation resistance, and the compression
residual deformation of the top cover is small compared with the cap
assembly of the traditional battery.