ELECTRODE ASSEMBLY, BATTERY CELL, BATTERY, AND METHOD AND DEVICE FOR MANUFACTURING ELECTRODE ASSEMBLY

An embodiment of the present application provides an electrode assembly, a battery cell, a battery, and a manufacturing method and device for the electrode assembly, which belong to the technical field of batteries. The electrode assembly includes a negative electrode plate and a positive electrode plate. The negative electrode plate includes a negative active material layer located in the straight area, and the positive electrode plate includes a positive active material layer located in the straight area. A first direction is perpendicular to an axial direction of a winding structure. The negative active material layer includes a negative electrode main body portion and negative electrode edge portions located on both sides of the negative electrode main body portion, and an active substance capacity per unit area of the negative electrode main body portion is greater than an active substance capacity per unit area of the negative electrode edge portion; and/or, the positive active material layer includes a positive electrode main body portion and positive electrode edge portions located on both sides of the positive electrode main body portion, and an active substance capacity per unit area of the positive electrode main body portion is less than an active substance capacity per unit area of the positive electrode edge portion. The electrode assembly of this structure can effectively reduce the risk of lithium plating and improve the safety of the battery.