面向摩擦纳米发电机电能存储的固态聚合物锂离子电池

The safe, convenient, and sustainable energy provision is an urgent issue for wearable electronic devices. The charging systems constituted by new triboelectric nanogenerator (TENG) and lithium ion batteries can address the key issue of wearable electronic devices. The application of TENG based charging systems in the wearable devices depends on the development of solid-state polymer lithium ion batteries (SPLB) with excellent rate performance, high safety performance, and superior cycling performance. However, the SPLB are still plagued by poor rate performance and limited cycling performance because of the low ionic conduction of solid-state electrolyte at room-temperature and interface issue. This project intends to address these issues by designing the cross-linking and inter penetrating co-polymerization network at molecular level, controlling the structure of electrospinning polymer skeleton at nanometer level, and in situ synthesis of the novel hierarchical solid-state polymer electrolyte. The advanced characterization methods and electrochemical measurement are carried out on the solid-state batteries, and the multi-scale model are established. The influences of polymer electrolyte components on the ionic conductivity and thermal stability of polymer electrolyte are investigated, the interphase properties of flexible electrodes are investigated, and thus the SPLB with high rate performance, excellent safe property, and outstanding cycling performance are expected. The improvement of power-storage efficiency of TENG based charging systems is investigated by a match between the TENG and the SPLB. This project will provide new ideas and theoretical basis for the scientific design of high performance SPLB for TENG based charging power systems.

安全、方便、持续的能源供应是可穿戴电子设备亟需解决的难题。新型摩擦纳米发电机（TENG）和锂离子电池组成的供能系统有望解决这一难题。开发倍率性能好、安全性高、循环性能出色的固态聚合物锂离子电池（SPLB）是TENG供能系统在可穿戴设备中成功应用的关键。然而，SPLB室温电导率低、界面性能差导致其倍率及循环性能不佳。本项目拟在分子水平设计聚合物的交联互穿网络结构，在纳米水平调控电纺纤维聚合物的结构，采用原位聚合的方式制备多级复合结构固态聚合物电解质以提高其离子电导率及界面性能。通过一系列的先进表征以及电化学测试，建立多尺度模型，研究聚合物电解质各关键组分影响离子电导率及热稳定性的规律，研究影响柔性电极界面性质、倍率性能、以及循环性能的关键因素，以期获得高倍率的室温SPLB。研究TENG与高倍率型SPLB之间的匹配耦合，为TENG在可穿戴设备中的成功应用提供新的思路和理论依据。

开发倍率性能好、安全性高、循环性能出色的固态聚合物锂离子电池（SPLB）是摩擦纳米发电机（TENG）供能系统在可穿戴设备中成功应用的关键。目前作为SPLB关键部分的固态聚合物电解质（SPE）存在着室温电导率低、热稳定性差等问题，导致SPLB的倍率性能不佳、循环寿命短等一系列问题。本项目通过原位聚合的方式构建分子、纳米、微米多尺度多级结构SPE来提升SPLB性能。研究发现分子尺度的不同聚合物单体共聚（如单臂与多臂共聚）以及双锂盐、多锂盐的协同效应，纳米尺度的二氧化硅和微孔分子筛的限域效应，微米尺度的多孔纤维结构对聚合度的调控等有利于多级结构SPE电导率、离子迁移数、热稳定性、以及电化学窗口的提高。分子尺度级别的调控更有利于SPLB界面稳定性、循环稳定性、倍率性能的提高。本项目优化制备的SPE的室温离子电导率可达1 mS cm-1，离子迁移数达到0.7，电化学窗口4.5 V，热稳定性可达200 ℃，其相应的锂离子电池500次循环的容量保持率在76%，圆满完成项目预期目标，为高性能SPLB的研发提供重要的理论依据和实践参考。.此外本项目还设计制备了一种超长寿命TENG及相应的智能管理电路为锂离子电池充电。TENG和锂离子电池的匹配耦合研究发现锂离子电池中的相转变反应和倍率性能优异的电极材料更适合储存TENG的脉冲电流，优化后的脉冲电流更有利于锂离子的扩散，减少浓差极化提高锂离子电池性能。项目的执行为TENG和锂离子电池组成的自供能系统的研发提供可靠的理论依据和实践参考。本项目发表SCI论文16篇（已标注），其中包括1篇Angew. Chem. Int. Ed.，两篇Adv. Sci.，两篇ACS Appl. Mater. Interfaces，两篇Nano Res., 一篇Nanoscale等国际著名期刊，申请国内发明专利两项。