Operando measurement of spatial temperature distribution in lithium-ion batteries with intelligent current collectors

Understanding spatial distribution of internal temperature is crucial for enhancing thermal management and ensuring safety of lithium-ion battery. Although implanting temperature sensor in the cell has been a promising approach to achieve operando measurement of internal temperature, challenges remain when using it to profile the spatial distribution of internal temperature with minimized degradation of battery performance. In this study, we propose intelligent current collector (ICC), which integrates the current collector and the temperature sensor array as a single device, to achieve in-situ measurement of spatial temperature distribution. With stacked integration of the temperature sensor array and the current collector, ICC is capable of measuring in-plane temperature distribution while serving as a normal current collector. The creation of vertical interconnect accesses in ICC effectively mitigates the adverse effects of embedded temperature sensors on the performance of current collector. By implanting ICCs in an NCM/graphite pouch cell using stacking process, ICC can monitor the spatial distribution of internal temperature with different charge/discharge rates, revealing the inhomogeneous in-plane and out-of-plane temperature distributions in the battery. Additionally, the location effect of external thermal stimulus is profiled using ICC, indicting the vulnerability of the edge of jelly roll to abnormal heat spreading.