金属锂|锂镧锆氧固态电解质界面反应动力学的现场谱学电化学研究

石榴石型锂镧锆氧（LLZO）固态电解质具有优异的机械强度、界面稳定性等优势，是未来固态锂电池的首选。但是，金属锂|LLZO界面存在浸润性差、界面电阻高等问题，亟需解决。虽然通过引入“亲锂”异质金属过渡层可有效调控金属锂|LLZO界面，获得优异的电化学性能，但对其内在机理不清晰，更缺乏深层次认知。本项目拟以LLZO基无锂固态电池为载体，构建锂合金|LLZO模型界面体系。结合一系列先进的表/界面谱学表征手段，深入理解“亲锂”与“憎锂”金属基界面过渡层对金属锂|LLZO界面调控作用的反应机理和化学本质，从而建立金属过渡层-界面性质-电化学性能间的构效关系，为固态金属锂电池的界面调控和集流体设计提供实验基础与理论指导。

Garnet-structured lithium lanthanum zirconium oxide (LLZO) is a solid-state Li+ conductor with excellent mechanical stiffness and interfacial robustness, which makes it the prime choice for future solid-state lithium batteries. However, the Li metal | LLZO interface is plagued by their poor mutual wettability and high interfacial resistance, the solution of which is still missing. Although “lithiophilic” (Li-alloying) metal interlayers have been demonstrated to regulate the Li-metal anode | LLZO interface and the concomitant improvement in electrochemical performance is substantial, the deep mechanism is still elusive and controversial. This study will adopt a “Li-metal free” solid-state cell as the model test vehicle, upon which various Li-alloy | LLZO interfaces will be fabricated. By combining a myriad of advanced surface/interface characterization techniques, the respective reaction mechanisms and chemical nature by which the “lithiophilic” and “lithiophobic” metal interfaces regulate the Li | LLZO interface will be uncovered. The general structure-activity relationship amongst the interlayer’s composition, interface property and the regulating efficiency will also be built upon it, which will provide experimental and theoretical foundation for the design of anode | electrolyte interface and current collectors of the future solid-state batteries.