Experimental and numerical investigation of a thermal management system for a Li-ion battery pack using cutting copper fiber sintered skeleton/paraffin composite phase change materials

The thermal safety of lithium-ion battery is a serious issue in its applications. A lithium-ion battery pack cooled by a cutting copper fiber sintered skeleton (CCFSS)/paraffin composite phase change material (PCM) is designed and fabricated. The effect of the CCFSS/paraffin composite PCM on the battery pack temperature is investigated by discharge experiments and compared with natural air cooling, pure paraffin, and copper foam/paraffin composite PCM. A two-equation non-thermal equilibrium model using the enthalpy method is established. The experimental results indicate that the battery temperature difference in the case with pure paraffin exceeds 5 °C, while the CCFSS/paraffin composite PCM effectively enhances the heat transfer performance and maintains the battery temperature differences within 5 °C. The numerical results show good agreement with the experimental data, validating the accuracy of the numerical model. Therefore, the effects of key parameters are investigated and predicted via the numerical model. The heating rate of the battery pack decreases with increases in the number of pores per linear inch (PPI) and the convective heat transfer coefficient. With the increase in the spacing between the cells, the heating rate of the battery pack decreases and the duration of the phase change increases. This work provided a reference for the application of CCFSS/paraffin composite PCM in the heat dissipation of lithium-ion batteries.