In this study, a three-dimensional transient simulation model of a liquid cooling thermal management system with flow distributors and spiral channel cooling plates for pouch lithium-ion batteries has been developed. The cooling plates play the role of uniforming temperature distribution and reducing the maximum temperature within each battery, while the flow distributors have the function of reducing the temperature difference between batteries in the battery module. The accuracy of the thermophysical properties and heat generation rate of the battery was verified experimentally. The optimal structure and cooling strategy of the system was determined by single factor analysis as well as orthogonal test and matrix analysis methods. The optimal solution resulted in a maximum battery module temperature of 34.65 °C, a maximum temperature difference of 3.95 °C, and a channel pressure drop of 8.82 Pa. Using the world-harmonized light-duty vehicles test cycle (WLTC) conditions for a battery pack in an electric car, the performance of the optimal battery thermal management system (BTMS) design was tested, and the results indicate that the maximum temperature can be controlled below 25.51 °C and the maximum temperature difference below 0.21 °C, which well meet the requirements of BTMS designs.