体内植入式热电-压电复合型柔性微发电构件研究

With extensive demands for the medical field, micro implantable medical devices (IMDs) have become one of the research focuses in the field of micro-systems and micro-manufacturing. However, the existing micro power or micro generators are unable to meet the power requirements of the long-term service of IMDs. Therefore, this project proposes a hybrid power generation method harvesting the in vivo heat and mechanical energy simultaneously. Then, a micro flexible thermoelectric- piezoelectric hybrid power generator with high efficiency and high energy density is designed. Furthermore, a low-cost fabrication method for the proposed micro-generator will be explored based on micro-contact printing of curved surface. The research mainly includes: (1) establish the structural design optimization model of the micro flexible thermoelectric-piezoelectric hybrid power generator for the in vivo environment; (2) investigate the process and theory of manufacturing and assembly for the micro flexible thermoelectric-piezoelectric hybrid power generator; (3) investigate the thermoelectric-piezoelectric coupling mechanism and regulation method for the hybrid power generator in order to optimize the system output; (4) develop the prototype of the micro flexible thermoelectric-piezoelectric hybrid power generator, and carry out power generation performance test. The research findings of the proposed project will provide a theoretical basis and technical support for the development of an implantable energy harvesting system, and also provide a new way to overcome the challenge for long-term service of IMDs.

面向医学领域的广泛需求，微小型可植入式医疗装置已成为微系统与微制造领域的研究热点之一。然而，现有的微小型电源或微发电器均无法满足体内植入式医疗装置长期服役的供电要求。为此，本项目提出同时收集生物体内热能和机械能的耦合发电思路，设计了一种高效、高能量密度的热电－压电复合型柔性微发电构件，并基于曲面微接触印刷技术探索该构件的低成本制造新方法。研究内容主要包括：(1)建立面向生物体内环境的热电－压电复合型柔性微发电构件的结构设计优化模型；(2)研究复合型微发电构件制造和装配的工艺及理论；(3)以优化系统输出为目标研究复合型微发电构件的热电－压电耦合机理和调控方法；(4)研制热电－压电复合型柔性微发电构件原型样机，并开展发电性能实验研究。研究成果将为体内植入式新型能量收集系统的研发提供理论基础和技术支撑，为解决体内植入式医疗装置的长期服役供电问题提供一条新途径。

针对穿戴式电子器件的供能需求和微型柔性温差发电器的设计和制造方面的难题，本项目在柔性温差发电器的结构设计、建模分析、制造工艺和测试驱动方面开展了研究。主要研究工作及取得的成果如下：1）建立非等截面积热电臂模组性能的分析模型，研究不同几何形状的热电臂对模组效率及当量功率密度的影响，得出梯形热电臂可以产生更高的当量功率密度；2）制造镀镍的Bi2Te3基热电模组，搭建热电模组的性能检测平台，通过发电性能测试和显微观察，分析镍阻隔层对模组性能与接触电阻的影响；3）建立包裹PDMS的柔性热电模组平面装载的二维数值模型，对不同边界条件及结构参数对模组性能的影响进行分析，并针对柔性热电模组曲面装载的情况，分析装载条件和导热界面材料的尺寸和材料参数对模组性能的影响；4）面向可穿戴式器件持续供能的应用场合，设计柔性温差发电器结构；5）设计人体余热回收应用的贴合式、表链式及多方向弯曲式的柔性温差发电器结构，进行制造工艺研究与性能测试，并可在人体穿戴场合通过升压驱动LED。本项目研究工作对穿戴式供能器件设计、微型柔性温差发电器的理论模型分析与设计制造技术等具有重要的指导和实际应用价值。项目执行期间共发表SCI论文9篇；申请国家发明专利9项，其中已授权发明专利4项、实用新型专利9项；培养博士后1名、博士生3名、硕士生4名。