Incorporating Cell Clamping and the Impact on Lithium-Ion Pouch Cell Performance

There have been more requirements for battery performance optimisation and degradation management with the growing trend of vehicle electrification. Therefore, battery thermal management systems and pack designs have been extensively studied to enable greater accessible cell capacity, safety, and longer lifespans. However, existing studies are mainly focused on either cooling systems or battery volumetric restraints independently. Regarding the lack of prominent study in a system that adopts both thermal management and the application of cell clamping, a novel test setup is introduced to combine these two systems and investigate the impact on lithium-ion pouch cells. This study proposes a cell clamping system which cuts out areas on a solid clamping plate to adopt immersion cooling with the aim to investigate the cell performance. Additionally, the thermal behaviour of the test cell with the proposed clamping system in the ambient environment and immersion cooling is assessed by measuring the temperature under the insulated pressure regions. The experimental results show that the covered area of the pouch cell surface exhibited lower temperature rise in ambient despite being insulated with the cell fixture system. When placed in the oil bath, the proposed heterogeneous side pressure fixture did not significantly increase the cell temperature at 1 C discharge rate while the cell discharge capacity and impedance were improved. This finding supports the possibility of incorporating cell clamping in battery thermal management systems for enhanced battery performance without significantly sacrificing cooling effect.