Organic Nanocoolant: An Environmental Friendly Solution for Battery Thermal Management in Electric Vehicles

An advanced battery thermal management system not only to protects the battery against thermal failure but also to do so without using coolants that contribute to global warming. Thermal runaway triggered by voltage irregularities, results in heat build-up during charging/discharging cycles, degrading battery lifespan and increasing the risk of fire and explosion hazards. This study investigates the thermal management of 18650 cylindrical lithium-ion battery packs using simulation-based analysis and optimization of direct immersion cooling techniques. A pack of 6 in series and 1 parallel (6S1P) battery is modeled under forced-air cooling and static-immersion cooling conditions to validate the numerical approach against existing experimental results. Subsequently, the thermal performance of a novel dielectric fluids, deep eutectic solvents and nanoparticle dispersed deep eutectic solvents, which are alternatives to hazardous chlorofluorocarbon-based coolants is evaluated using a 4 × 4 pack of 16 in series and 1 parallel (16S1P) battery pack model. Studies are conducted by varying coolant flow rate, cell-to-cell and cell-to-wall spacing, inlet-outlet configurations, and cell arrangement (inline and staggered) to identify optimal operating parameters. These results identify the configuration which ensures uniform temperature distribution and improved cooling efficiency, contributing to safer and more effective battery thermal management systems for electric vehicles.