A secondary battery, comprising: a top cover plate, having an outer surface and an inner surface disposed opposite each other in a thickness direction of the top cover plate and an electrode lead-out hole extending along the thickness direction; a pole, disposed in the electrode lead-out hole, wherein the pole comprises a first metal layer and a second metal layer, and the first metal layer and the second metal layer are stacked along a direction from the inner surface to the outer surface; an insulation member, disposed between the top cover plate and the pole; and a first bonding layer, disposed between the insulation member and the first metal layer, wherein the first metal layer and the first bonding layer are bonded by a chemical bond, the insulation member and the first bonding layer are bonded by a chemical bond, and the insulation member is hermetically connected to the first metal layer through the first bonding layer; wherein the first metal layer has a first concave portion facing away from the second metal layer, part of the insulation member extends into the first concave portion, and the first bonding layer extends to between the first concave portion and the insulation member; wherein the secondary battery further comprises a second bonding layer, the second bonding layer is disposed between the insulation member and the second metal layer, the second metal layer and the second bonding layer are bonded by a chemical bond, the insulation member and the second bonding layer are bonded by a chemical bond, and the insulation member is hermetically connected to the second metal layer through the second bonding layer; the second metal layer has a second concave portion facing away from the first metal layer, part of the insulation member extends into the second concave portion, and the second bonding layer extends to between the second concave portion and the insulation member. a top cover plate, having an outer surface and an inner surface disposed opposite each other in a thickness direction of the top cover plate and an electrode lead-out hole extending along the thickness direction; a pole, disposed in the electrode lead-out hole, wherein the pole comprises a first metal layer and a second metal layer, and the first metal layer and the second metal layer are stacked along a direction from the inner surface to the outer surface; an insulation member, disposed between the top cover plate and the pole; and a first bonding layer, disposed between the insulation member and the first metal layer, wherein the first metal layer and the first bonding layer are bonded by a chemical bond, the insulation member and the first bonding layer are bonded by a chemical bond, and the insulation member is hermetically connected to the first metal layer through the first bonding layer; wherein the first metal layer has a first concave portion facing away from the second metal layer, part of the insulation member extends into the first concave portion, and the first bonding layer extends to between the first concave portion and the insulation member; wherein the secondary battery further comprises a second bonding layer, the second bonding layer is disposed between the insulation member and the second metal layer, the second metal layer and the second bonding layer are bonded by a chemical bond, the insulation member and the second bonding layer are bonded by a chemical bond, and the insulation member is hermetically connected to the second metal layer through the second bonding layer; the second metal layer has a second concave portion facing away from the first metal layer, part of the insulation member extends into the second concave portion, and the second bonding layer extends to between the second concave portion and the insulation member.