The welding quality of the positive electrode in lithium-ion batteries directly affects internal resistance, safety, and cycle life. To address issues such as insufficient strength, overwelding, and poor consistency caused by overly broad welding parameter windows (amplitude, energy, pressure) in current production, a Design of Experiments (DOE) method is introduced for process optimization. Initially, through a full factorial experiment with three factors and two levels, it is found that the initial parameter range (amplitude 30~60 μm, energy 40~100 J, pressure 30~60 MPa) is generally in an "over-welded" state, with amplitude identified amplitude identified as the most critical influencing factor. Based on this, the study further adopts the Box-Behnken response surface design to construct quantitative models for tensile force, peel force, and welding effectiveness within a narrowed parameter space. The results indicate that within lower parameter intervals, the contribution of energy and amplitude to welding quality shifts from negative to positive. Through multi-response variable optimization, the optimal process parameter combination is determined as amplitude 36 μm, energy 50 J, and pressure 40 MPa. Verification experiments confirms that under this parameter combination, the welded joints exhibit excellent mechanical properties, ideal foil adhesion rates, and significantly improved process stability. This provides a reliable basis for achieving refined control and mass production consistency in positive electrode welding.