Improving Thermal Management of Li-ion Batteries in Electric Vehicles: A CFD Study of a Hybrid System with Nanofluid and Peltier Module

Abstract

Efficient thermal management is crucial for optimizing the performance, safety, and longevity of lithium-ion batteries in electric vehicles (EVs). This study introduces a novel hybrid Battery Thermal Management System (BTMS) that integrates nanofluid and Peltier module to enhance heat dissipation and maintain optimal temperature ranges. The system operates in a closed-loop configuration, where the nanofluid circulates to absorb heat from the battery and is subsequently cooled by the Peltier module before being recirculated. Using Computational Fluid Dynamics (CFD), alongside the Newman Tiedemann Gu and Kim (NTGK) model, the thermal behavior was simulated in ANSYS Fluent. The thermal profile of the 32140 Series 15 Ah Li-ion cell illustrates the highest internal maximum temperature and cell surface temperature at discharge rate 10C, followed by 7C and 5C, respectively. The CuO/DI water nanofluid was prepared at 0.1 w/v% concentration with a surfactant-to-nanoparticle weighted ratio of 1:2.5. Furthermore, the nanofluid sample exhibits a maximum enhancement in thermal conductivity of 9.928% relative to deionized water, which justifies its application in thermal applications like BTMS. The proposed BTMS effectively reduced the maximum temperature rise of the cell 32140. Compared to the temperature rise observed without BTMS, the reductions achieved were as follows: 1.6% at a 5C discharge rate, 10.8% at a 7C discharge rate, and 19.5% at a 10C discharge rate. The findings emphasize the system's potential to extend battery life by minimizing degradation rates. This research highlights the potential of integrating nanofluids and Peltier modules in advanced BTMS designs, offering a promising approach to enhance the operational stability and safety of Li-ion batteries in EV applications.