An electrode assembly includes first and second electrode plates having opposite polarities, and stacked and wound in a winding direction to form a wound structure. The first electrode plate has a first winding starting end and includes a first segment and a second segment continuously arranged along the winding direction. The first segment is wound from the first winding starting end along the winding direction to form an inner turn layer, and the second segment is wound from a connecting position where it is connected with the first segment along the winding direction to form an outer turn layer. The first segment is provided with a reinforcing part wound to the connecting position along the winding direction and configured to reinforce the first segment.