Abstract: A battery cell includes a case having an opening and an end cover configured to cover the opening. The end cover comprises an end cover body and a support body. The end cover body is configured to be welded and fixed to the case. The support body is disposed on a bottom surface of the end cover body and is disposed along an edge of the end cover body in a circumferential direction. The support body is configured to abut against an inner side surface of the case.

Abstract: The embodiments of the application provide an electrode assembly and a manufacturing method and manufacturing system therefor, a battery cell and a battery. The electrode assembly includes a positive pole piece and a negative pole piece, a positive active material layer of the positive pole piece and a negative active material layer of the negative pole piece are arranged oppositely, and an end of the negative active material layer extends beyond the positive active material layer. The negative active material layer includes a negative body portion and a negative edge portion, one end of the negative edge portion extends beyond the positive active material layer, and/or the positive active material layer includes a positive body portion and a positive edge portion. The electrode assembly of this structure can reduce a risk of lithium plating of the pole piece.