Power battery and welding method of sealing nail of power battery

The invention relates to a power battery and a welding method of a sealing nail of the power battery. The welding method of the sealing nail mentioned above is used for welding the sealing nail on a cover plate of the power battery. The welding method of the sealing nail comprises that impurities in a containing groove of the cover plate are cleaned through a first laser, and meanwhile, a first protective gas is blown to the action part of the first laser along a first preset angle between the plane where the first protective gas is located and the plane where the cover plate is located, wherein the focal point of the first laser is located in the containing groove, and the distance from the focal point of the first laser to the bottom of the containing groove is S1; the sealing nail is placed in the containing groove, so that an uneven annular gap exists between the sealing nail and the containing groove; the sealing nail is positioned and fixed in the containing groove in a spot welding mode through a second laser, and meanwhile, a second protective gas is blown to the action part of the second laser; and the sealing nail and the cover plate are welded through the second laser along the annular gap. According to the power battery and the welding method of the sealing nail of the power battery mentioned above, the problem that impurities or explosion points occur when the sealing nail is welded to the cover plate.