锌-空气电池大电流充放电条件下锌电极失效机理研究

Zinc-air batteries possess a variety of advantages of high specific energy, low cost, and good safety, but the cycle life of the battery is too short. With the development trend of high current charge-discharge, the issue of cycle life becomes more prominent. Therefore, the project aims to reveal the failure mechanism of zinc-air batteries, extending the cycle life of the battery at the high current charge-discharge cycle. As zinc electrode influences the cycle life of zinc-air batteries, the project intends to study morphological change model of zinc electrode, reveals the mechanism of morphological change of zinc electrode under the condition of high current charge, and illustrates the distribution law of parameters influencing the morphological change. The project intends to study the failure model of zinc electrode during discharge, reveals the aging mechanism of zinc electrode and influence factors during large current discharge, and provides the performance degradation law of zinc electrode. The project intends to study measures to extend the cycle life of zinc-air batteries, including battery structure optimization, the charge process optimization, and the discharge process optimization. The main innovation of the project is reflected in the battery structure innovation and the research content, namely the research is based on zinc-air battery with the invention of the self-protected air electrode, and the failure mechanism research of zinc electrode of zinc-air batteries with the large current charge/discharge is rarely reported. The results will be conducive to developing the theory of zinc-air battery and promoting the technological progress of zinc-air batteries in application of power supply and energy storage.

锌-空气电池具有比能量高、成本低、安全性好等优势，但循环寿命短，特别是在大电流充放电发展趋势下循环寿命问题更突出。为此，本项目旨在揭示锌-空气电池失效机理，延长电池大电流充放电循环寿命。针对锌电极影响电池寿命问题，研究锌电极形貌变化模型，揭示大电流充电条件下锌电极形貌变化机制，阐明影响形貌变化的参数分布规律；研究锌电极失效模型，揭示大电流放电过程中锌电极老化机理及影响因素，给出锌电极性能衰减规律；研究寿命延长措施，包括电池结构优化、充电过程优化、放电过程优化。主要创新体现在电池结构创新和研究内容创新，用发明的自保护空气电极组建电池为开展大电流研究提供条件，针对大电流下锌-空气电池锌电极失效机理研究未见报道。研究结果将发展锌-空气电池理论，促进锌-空气电池在动力电源和规模储能领域的技术进步。

锌-空气电池具有比能量高、成本低、安全性好等优势，且拥有较好的电化学可逆性和稳定的电化学性能；但锌电极表面结构与形貌影响电池的循环寿命，大电流充放电条件下锌电极失效尤为突出。本项目研究了大电流充电条件下锌电极形貌变化机制，建立了锌电极的形貌变化相场模型，揭示了大电流充电条件下离子扩散受限、电子传输受阻、晶体螺旋位错锌枝晶生长机制，提出了电解质重整、局部导电结构和多物理场耦合控制锌电极形貌变化。研究了大电流放电条件下锌电极老化机制，建立了锌电极的失效模型，揭示了大电流放电过程中锌电极老化影响因素，提出了钛过滤器净化电解液，稳定锌电极放电性能。研究了空气电极水淹、气孔堵塞、催化剂脱落和锌枝晶生长对锌-空气电池充放电性能的作用机制，建立了充电式锌-空气电池数学模型，提出了充放电电极并联结构和电磁耦合措施，延长锌-空气电池的循环寿命。通过对大电流锌电极失效机理研究，发表了SCI论文12篇，申请了3项专利，为锌-空气电池动力电源和静态储能应用提供系统的理论基础和技术指导。