小空心锰酸锌@导电聚合物yolk-shell结构微球功能设计、结构调控及其储能构效关系

Considering the synergetic Li-storage advantages from multiple metal species, spinel ZnMn2O4 (ZMO) is becoming one of researching hotspots in Li-ion batteries (LIBs). With low Colombic efficiency, modest electronic conductivity and the conflict between high capacity/long-cycle life and structural stablility, herein, we proposed controllable synthesis of high-performance mini-hollow ZMO@conducting polymers (CPs) microspheres with yolk-shell structure via elegant combination of fine experiments, and theoretical modeling and mathematical simulation, acoording to the synergetic contribution from “mini-hollow”, “yolk-shell” and “stable SEI”. The underlying one-step bottom-up formation mechanism and the influence of hollow volume upon structural stability were revealed in detail. With in-/ex-situ charactrizations and typical electrochemical devices, complex Li-storage processes from multiple species and abnormal capacity-increase mechanism were presented on atomic scale. The effecting mechanism of CPs type, void microstructure, sur-/interface charge transfer between functional components on the enhancement in electrochemical Li-storage behaviors and stablizing mechanism of SEI were demonstrated. The inherent relationship and interaction theory between functional composition/component, microstructure, and electrochemical Li+-storage performance were rationally established. Finally, new insights and fundamental guidance were provided for further design, fabrication and practical applications of high-performance anodes for advanced LIBs.

鉴于多元金属协同储锂优势，尖晶石结构ZnMn2O4成为目前锂离子电池负极材料研究重点之一。针对其库伦效率低、导电性差、高比容量/长寿命与其结构稳定性不可兼顾的关键问题，在研究基础上，本项目拟基于“小空心”、“yolk-shell”和“稳定SEI膜”耦合作用理念，采用实验精细调控和理论模拟计算有机融合，可控构筑高性能小空心ZnMn2O4@导电聚合物yolk-shell结构微球负极材料。揭示“小空心”ZnMn2O4微球“自下而上”一步形成机制及空心体积对其结构稳定性的影响规律。借助（非）原位表征及电化学装置，微尺度阐明复杂多组元协同储锂及反常容量“递增”机制。获知导电聚合物种类/存在形态、空腔结构、功能组分表/界面传荷对储锂性能提升的作用机制及SEI膜稳定机理。构建“功能组元/组分−微结构−电化学储锂性能”内禀构效关系及作用规律，为先进锂电池负极材料设计、构建及应用开发提供理论指导和科学依据。

鉴于多元过渡金属协同储锂优势，尖晶石结构锰酸锌（ZnMn2O4）成为目前锂离子电池负极材料的研究热点和重点之一。针对ZnMn2O4首次库伦效率低、自身电子导电性差、高比容量/长寿命与其结构稳定性不可兼顾的关键瓶颈难题，本项目基于“小空心”、“yolk-shell”和“稳定SEI膜”复合耦合作用理念，采用精细实验调控和理论模拟计算有机融合，可控构筑了高性能小空心ZnMn2O4@导电聚合物yolk-shell结构微球负极材料。深入揭示了“小空心”ZnMn2O4微球“自下而上”一步形成机制及空心容积对其结构稳定性的影响规律和内在机制。并借助（非）原位表征及电化学装置，微尺度系统阐明了复杂多组元协同储锂及反常容量“递增”作用理论。获知了导电聚合物种类/存在形态、空腔微观结构、功能组分表/界面传荷对电化学储锂性能提升的作用机制及SEI膜稳定机理。最终构建了“功能组元/组分−微结构−电化学储锂性能”内禀构效关系及作用规律，为开发具有高比容量/高倍率、长寿命、高安全性和高结构稳定性新型低成本先进锂离子电池负极材料设计、构建及应用提供关键技术支持、器件原型和科学理论指导。