Experimental investigation of lithium-ion battery thermal management for electric vehicles using mini channels cold plate and phase change material

Abstract

Effective thermal management of lithium-ion batteries is essential for ensuring safety in electric vehicles. Although these batteries offer a long lifespan and high energy density, they can also pose risks, such as increased temperature, that can lead to thermal runaway, battery damage, or even explosions. This study presents an innovative hybrid cooling model that integrates a water cooling system with mini-channel cold plates and an air cooling system with extended fins, both of which incorporate a phase change material. The aim is to experimentally investigate the thermal management system (BTMS) for lithium-ion battery packs in electric vehicles operating under high ambient temperature. The performance of the BTMS was evaluated at battery discharge rates of 1C, 2C, and 3C, with varying cooling water flow rates, at inlet water and ambient temperatures of 25 °C and 35 °C, respectively. The results showed that the hybrid cooling system, operating at a lower water flow rate of 0.0033 kg/s, successfully reduced the maximum battery temperature ($T_{\max }$) to 34 °C, 43.5 °C, and 51.6 °C for discharge rates of 1C, 2C, and 3C, respectively. Additionally, the maximum difference between the battery pack cell’s temperatures (${\Delta T}_{\max }$) were 0.7 °C, 2.2 °C, and 4.3 °C, respectively. Furthermore, a higher flow rate of 0.05 kg/s resulted in $T_{\max }$ of 30.5 °C, 40 °C, and 47.3 °C, with corresponding ${\Delta T}_{\max }$ of 0.5 °C, 1.5 °C, and 2.5 °C respectively. The proposed hybrid model successfully maintained a ${\Delta T}_{\max }$ of less than 5 °C, highlighting the effectiveness of this cooling system for ensuring battery safety.