Electrode assembly, battery cell, battery and electric device

The embodiment of the invention provides an electrode assembly, a battery monomer, a battery and a power utilization device. The electrode assembly comprises a first pole piece, a second pole piece and an isolating membrane, the first pole piece, the second pole piece and the isolating membrane are wound to form the electrode assembly, the isolating membrane is used for isolating the first pole piece and the second pole piece, and the polarities of the first pole piece and the second pole piece are opposite; wherein the first pole piece comprises a first area and a second area, the first area and the second area are sequentially and alternately arranged and connected in the winding direction, after the electrode assembly is wound, at least part of the second area is located at the bent part of the first pole piece, the first area is coated with a first active material, and the second area is coated with a second active material; the expansion rate of the second active material is less than that of the first a