辐致伏特/光伏双重效应多级同位素电池能量转换机制与性能优化研究

According to the urgent demand for “high-efficiency & long-lifetime space nuclear battery technology” in the 13th Five-Year National Space Plan, a new dual energy conversion mechanism utilizing both radia-voltaic and radia-photovoltaic effects was proposed in this project. The project provides new ideas for the isotope battery theory and its preparation technology for the space exploration. This project intends to reveal the compound energy conversion mechanisms of “gamma decay energy to electric energy” and “gamma decay energy to photon energy to electric energy”. In order to realize efficient dual energy conversion, the functional mechanism between the semiconductor physical parameters and micro-nano structure of voltaic layer and the dual energy conversion effects will be studied. The relationship between gamma-ray characteristic parameters and radial luminescence efficiency will be discussed in detail. At the same time, a method for the fluorescence spectrum regulation and emission enhancement will be explored. Based on the above studies, the efficient coupler matching of voltaic layers and scintillator layers in the multilevel structure will be realized. Then, one radiation equivalent environment effect experiment will be carried out on the fabricated battery prototypes. The performance stability and service life of batteries can be evaluated and improved. This project aims to achieve “Conversion” optimization for isotope decay energy, “Loss” minimization, and “Output” maximization. A new isotope battery based on 60Co gamma source and multilevel compound energy conversion units with “voltaic layers and scintillator layers” will be developed in this project. This project will lay a foundation for exploring and verifying the feasible technology of efficient energy conversion and mW ~ W magnitude long-lifetime space isotope batteries.

基于我国航天《十三五》规划关于“高效率长寿命空间核电源技术”的迫切需求，探索辐致伏特/光伏效应相结合的双重能量转换新机制，为发展空间探索等领域所亟需的同位素电池理论及其研制技术开拓新思路。本项目拟研究揭示“γ衰变能→电能”+“γ衰变能→光能→电能”的混合换能机制；探究伏特层半导体物理参数及微纳结构与双重换能效应之间的作用机理，实现电池的双重高效换能；研究γ射线特性参数与辐致发光效率之间的响应关系，探索荧光光谱调控和发射增强方法，实现闪烁层与伏特层多级结构的高效耦合匹配；以制备样品为测试对象进行等效辐照环境效应实验，评估并改良电池性能稳定性及服役寿命；以期达到同位素衰变能量的“转换”最优化、“损耗”最小化以及“输出”最大化。项目将研发出一种采用Co-60 源、“伏特层+闪烁层”多级复式换能单元的新型同位素电池，为探索和验证高能量转化效率、mW-W量级长寿命空间同位素电池的可行性技术奠定基础。

同位素电池技术在深空探索、航天器件及电子设备的供电系统研发等领域具有重要意义，然而其实际应用与发展严重受限于其输出性能和稳定性。本项目在总结剖析当前同位素电池技术以及国内外研究进展的基础上，提出将“辐致伏特效应”和“辐致光伏效应”这两种能量转换机制综合利用，通过集之所长、避之所短，探索出可实现能量转换效率大幅提升的有效措施和设计方案。项目研发出一种基于60Co γ放射源的新型辐致伏特/光伏双重效应多级同位素电池，并围绕多级双重效应同位素电池的材料参数、结构设计、样品制备以及γ辐照损伤效应开展了一系列的深入研究，具体包括：1）建立了基于辐致伏特效应和辐致光伏效应相结合的双重效应多级同位素电池计算模型，剖析了其内在响应规律，获得了实现mW量级功率输出的设计方案；2）完成了伏特层材料与结构的设计、制备及电学性能测试，确定了伏特层的结构设计和物理参数；3）探究了γ射线与闪烁层之间的响应关系，实现不同级中闪烁层与伏特层的高效耦合匹配；4）在剂量率为0.103 kGy/h的60Co源激发下，优化后的双重效应同位素电池的开路电压和最大输出功率分别可达到7.77 V和7.98 μW，能量转化效率提升近一个数量级，且电学输出性能随源条件的增强也会更优；5）完成了射线对新型“伏特层+闪烁层”多级复式换能单元的长期作用效应研究，揭示了材料的辐照损伤机制。项目在新型同位素电池的能量转换机制、器件结构设计、功能材料制备、电池性能评价等方面拓展了研究思路，丰富了我国航天十三五规划中“高效率长寿命空间核电源技术”的研究内涵。