Wang Wentian, Zou Jie, Ni Yongjian, Yu Kaige, Yan Xinxin, Yin Jiawen, Gao Wanlei, Chen Daidai, Jin Qinghui, Jian Jiawen
Faculty of Electrical Engineering and Computer Science, Ningbo University, Ningbo 315211, China.
State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
ACS Appl Mater Interfaces. 2024 Sep 18;16(37):49733-49744. doi: 10.1021/acsami.4c07661. Epub 2024 Sep 4.
This paper presents a comprehensive study of the structural optimization of polyimide-film (PI-film) capacitive humidity sensors, with a focus on enhancing their performance for application in new energy vehicles (NEVs). Given the critical role of humidity sensors in ensuring the safety and efficiency of vehicle operations─particularly in monitoring lithium-ion battery systems─the study explores the intricate relationship between the interdigitated electrode (IDE) dimensions and the PI-film thickness to optimize sensor responsiveness and reliability. Through a combination of COMSOL Multiphysics simulations (a powerful finite element analysis, solver, and simulation software) and experimental validation, the research identifies the optimal geometrical combination that maximizes the sensitivity and minimizes the response time. The fabrication process is streamlined for batch preparation, leveraging the spin-coating process to achieve consistent and reliable PI films. Extensive characterizations confirm the superior morphology, chemical composition, and humidity-sensing capabilities of the developed sensors. Practical performance tests further validate their exceptional repeatability, long-term stability, low hysteresis, and excellent selectivity, underpinning their suitability for automotive applications. The final explanation of the sensing mechanism provides a solid theoretical foundation for observed performance improvements. This work not only advances the field of humidity sensing for vehicle safety but also offers a robust theoretical and practical framework for the batch preparation of PI-film humidity sensors, promising enhanced safety and reliability for NEVs.
本文对聚酰亚胺薄膜（PI薄膜）电容式湿度传感器的结构优化进行了全面研究，重点是提高其在新能源汽车（NEV）中的应用性能。鉴于湿度传感器在确保车辆运行的安全性和效率方面的关键作用，特别是在监测锂离子电池系统方面，该研究探讨了叉指电极（IDE）尺寸与PI薄膜厚度之间的复杂关系，以优化传感器的响应性和可靠性。通过结合COMSOL Multiphysics模拟（一款强大的有限元分析、求解器和模拟软件）和实验验证，该研究确定了能使灵敏度最大化和响应时间最小化的最佳几何组合。制造工艺通过旋涂工艺进行简化以实现批量制备，从而获得一致且可靠的PI薄膜。大量表征证实了所开发传感器具有优异的形态、化学成分和湿度传感能力。实际性能测试进一步验证了它们具有出色的重复性、长期稳定性、低滞后性和卓越的选择性，这证明了它们适用于汽车应用。传感机制的最终解释为观察到的性能提升提供了坚实的理论基础。这项工作不仅推动了车辆安全湿度传感领域的发展，还为PI薄膜湿度传感器的批量制备提供了一个强大的理论和实践框架，有望提高新能源汽车的安全性和可靠性。
