A secondary battery includes a positive electrode having a positive electrode current collector and a positive electrode active material layer; a negative electrode having a negative electrode current collector and a negative electrode active material layer; a separator interposed between the electrodes; a electrolyte; a positive electrode lead; and an insulating tape that covers part of the positive electrode. The positive electrode current collector has an exposed portion connected to the positive electrode lead. The positive electrode lead has an extending portion that projects from the exposed portion and an overlapping portion that overlaps the exposed portion. At least part of the exposed portion and at least part of the overlapping portion are covered with the insulating tape. The insulating tape has a substrate layer and an adhesive layer. The substrate layer contains a polyimide. The adhesive layer has an electrical resistance of 1 kΩ/mm2 or more at 500° C.