Positive pole piece for secondary battery and secondary battery

The invention relates to the technical field of batteries, in particular to a positive pole piece for a secondary battery and the secondary battery, the positive pole piece comprises a positive current collector and a positive active material coated on the surface of the positive current collector, and the positive active material comprises lithium iron phosphate and a single-walled carbon nanotube, the single-walled carbon nanotubes are dispersed in the lithium iron phosphate of the positive pole piece, and part of the single-walled carbon nanotubes are attached to the particle surface of the lithium iron phosphate; the weight ratio A of the single-walled carbon nanotubes, the specific surface area BET of the single-walled carbon nanotubes in the positive pole piece and the tube length distribution width D of the single-walled carbon nanotubes meet the following relational expression: 1.8 < = 100A * BET/D < = 23.5; the unit of the specific surface area BET of the single-walled carbon nanotube is m < 2 >/g, a