Thermal management is crucial for lithium-ion batteries to ensure safe operation, high performance, and long lifetime. In this regard, the thermophysical properties of the batteries are key parameters for developing reliable and accurate thermal models. This study presents a new, simple, and cost-effective method for determination of heat capacity and anisotropic thermal conductivity of a commercial high energy density (43 Ah) prismatic-shape lithium-ion battery. The influence of various operating temperatures on thermal parameters is investigated. The predicted heat capacity and thermal conductivity are then used to simulate the battery cell temperature at a high current charge and discharge rate using a lumped thermal network and a three-dimensional (3D) thermal model at different environment temperatures. Additionally, the thermal behavior of a 48 V battery module consisting of 12 cells is simulated using a 3D thermal model at room temperature. Both cell and module level simulations are validated with experimental results obtained by thermocouples and a thermal camera. The thermal characterization results reveal that the heat capacity of the battery slightly increases as the operating temperature increases, while the thermal conductivity remains independent of the temperature. The comparison of simulation and experimental results indicate that the developed method in this study is a quick and practical way to accurately predict the thermophysical properties of the battery and contribute towards the thermal management of Li-ion modules and packs.