A balanced structural optimization on the strength of the response surface method is conducted for the battery module with a single-layer sleeved heat spreader plate (SHSP). The module contains 4 × 5 cylindrical batteries, connected with the SHSP through the tubular sleeve structure. The SHSP structure, simple yet reliable in construction, not only enlarges the heat dissipation area of module but also facilitates temperature uniformity across the batteries through on-plate heat spreading. First, the numerical model is constructed to examine the thermal performance of module. The sensitivity of the structure parameters, including the SHSP thickness, sleeve structure height, caudal length of SHSP, and central distance of batteries, are examined. A balanced optimization is then conducted by varying the structural parameters to obtain the objective functions based on central composite design. Besides the temperature maxima and temperature nonuniformity, the nonthermal metrics such as the pressure differential and the mass of SHSP are also taken as the design objectives to obtain an optimal configuration between performance and energy efficiency. Moreover, the effect of inlet velocity on the module performance is studied. The results indicate that with the optimal SHSP configuration, the temperature nonuniformity of module can be minimized even under lower fan power consumption.