College of Material Science and Engineering, Sichuan University, Chengdu 610064, China.
Sensors (Basel). 2023 May 25;23(11):5049. doi: 10.3390/s23115049.
Sorts of Li-ion batteries (LIB) have been becoming important energy supply and storage devices. As a long-standing obstacle, safety issues are limiting the large-scale adoption of high-energy-density batteries. Strategies covering materials, cell, and package processing have been paid much attention to. Here, we report a flexible sensor array with fast and reversible temperature switching that can be incorporated inside batteries to prevent thermal runaway. This flexible sensor array consists of PTCR ceramic sensors combined with printed PI sheets for electrodes and circuits. Compared to room temperature, the resistance of the sensors soars nonlinearly by more than three orders of magnitude at around 67 °C with a 1 °C/s rate. This temperature aligns with the decomposition temperature of SEI. Subsequently, the resistance returns to normal at room temperature, demonstrating a negative thermal hysteresis effect. This characteristic proves advantageous for the battery, as it enables a lower-temperature restart after an initial warming phase. The batteries with an embedded sensor array could resume their normal function without performance compromise or detrimental thermal runaway.
锂离子电池（LIB）种类繁多，已成为重要的能源供应和存储设备。安全性问题一直是限制高能量密度电池大规模应用的一个长期障碍。涵盖材料、电池和封装处理的策略受到了广泛关注。在这里，我们报告了一种具有快速和可逆温度切换功能的柔性传感器阵列，可以集成到电池内部以防止热失控。该柔性传感器阵列由 PTC 陶瓷传感器与用于电极和电路的印刷 PI 片组成。与室温相比，传感器的电阻在 67°C 左右以 1°C/s 的速率非线性飙升超过三个数量级。这个温度与 SEI 的分解温度一致。随后，在室温下电阻恢复正常，表现出负的热滞后效应。这种特性对电池有利，因为它可以在初始加热阶段后以较低的温度重新启动。嵌入传感器阵列的电池可以在不影响性能或发生有害热失控的情况下恢复正常功能。
