CFD analysis of a PCM-based TMS for a Li-Ion pouch cell

Organic Phase Change Materials (PCMs) such as paraffins, fatty acids, and esters present good properties to be used as Thermal Management System (TMS) for Li-Ion Batteries (LIB). The temperature of LIB cells should be ideally kept in the range of 25-35°C to maximise performances and minimise degradation. This represents a good opportunity to exploit the quasi-isothermal solid-liquid phase-change process of PCMs. Thanks to their high thermal energy densities, the use of PCMs limits the increment of TMS volume. Thus, by using PCMs in LIB TMS, it is possible to keep the LIB cells’ temperature nearly constant (when the PCM is changing phase) both during charging and discharging cycles. In this study, a numerical model based on the enthalpy-porosity method implemented in Ansys Fluent was developed to investigate the PCM behaviour in a LIB pouch cell TMS. The model was validated against experimental data.