Thermal Modeling of a Cylindrical Lithium-Ion Battery in 3D with the Taguchi Optimization Method

Thermal management is critical for the safety, performance, and life cycle of lithium-ion (Li-ion) batteries. This study aims to determine the optimum settings and contribution levels of key parameters affecting the operating temperature of a three-dimensional (3D) thermal model of a cylindrical Li-ion battery. A Taguchi L9 orthogonal array was designed with four: (A) base fluid and (B) Al2O3volume fraction (Φ-Al2O3) of the nanofluid coolant, (C) battery–battery distance, and (D) inlet temperature (Tinlet), each varied on 3-level control factors. To minimize the maximum battery temperature (Tmax), the “smaller-is-better” signal-to-noise (S/N) ratio approach and Analysis of Variance (ANOVA) were applied. The S/N analysis and ANOVA revealed that the base fluid (A: 44.96%) and Tinlet (D: 36.00%) were the most dominant factors influencing the Tmax. The optimal design identified by the Taguchi method (A3-B3-C3-D1) successfully reduced the Tmax to 33.5 °C, a 29.0 °C reduction compared with the initial air-cooled reference model (62.5 °C). Furthermore, the maximum temperature rise during the 2100 s operation was reduced by approximately 62%. This optimal Tmax of 33.5 °C was even lower than the best result in the L9 array (35.5 °C), validating the strong predictive capability of the method.