Pole piece, electrode assembly, battery monomer, battery and electric device

The invention discloses a pole piece, an electrode assembly, a battery monomer, a battery and an electric device. The pole piece comprises a main body part, wherein at least part of the surface of the main body part is coated with an active substance; the tab part is arranged on at least one side of the main body part, and the tab part is connected with the main body part; the opening penetrates through the tab part in the thickness direction of the tab part, the opening is provided with a first end and a second end, the first end and the second end are sequentially arranged in the direction away from the main body part, and the opening extends from the first end to the second end along a preset route. According to the pole piece provided by the embodiment of the invention, in the production and manufacturing process, the phenomenon that the tab part is folded can be reduced, so that the situation that the overcurrent area of the tab part is insufficient is avoided, heat generated by the tab part is reduced w