An electrode assembly includes an electrode main body, the electrode main body has a first direction, a second direction and a third direction that are orthogonal to each other, and includes two main surfaces, two end surfaces, and two side surfaces, and the coating device includes a discharge assembly, a cutting assembly and a first coating assembly. The discharge assembly is used to store and release a material strip, which includes a plurality of coating films connected in sequence along a length direction of the material strip, and each coating film includes two main coating areas spaced apart from each other and a connecting area connected between the two main coating areas. The cutting assembly is used to cut a head end coating film located at a head end of the material strip from the material strip.