Ling Huajin, Shen Lu, Huang Yanfei, Ma Jiabin, Chen Likun, Hao Xiaoge, Zhao Liang, Kang Feiyu, He Yan-Bing
Shenzhen Geim Graphene Center, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, P. R. China.
Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
ACS Appl Mater Interfaces. 2020 Dec 23;12(51):56995-57002. doi: 10.1021/acsami.0c16390. Epub 2020 Dec 11.
All-solid-state batteries have become the most potential next-generation energy-storage devices. However, it is quite difficult to simultaneously achieve a single solid-state electrolytes (SSEs) layer with both dendrite-free Li metal plating and low interfacial resistance between the cathode and SSEs. Herein, an integrated structure of cathode and double-layer solid electrolyte membrane (IS-CDL) is designed, which greatly improves the interfacial contact and suppresses the Li dendrite growth. The first "polymer in ceramic" solid electrolyte layer (SL1) consists of 80 wt % LiAlTi(PO) (LATP) nanoparticles and 20 wt % polyethylene oxide (PEO), and the second polymer electrolyte layer is PEO-based solid electrolyte layer (SL2). The SL1 with high mechanical properties can hinder the growth of Li dendrites and reduce the interfacial resistance with the cathode. The SL2 can inhibit the side reaction between the Li metal and LATP. The Li symmetric cells with sandwich-type hierarchical electrolyte (SL2/SL1/SL2) can stably cycle over 3200 h at 0.1 mA cm at 45 °C. The obtained all-solid-state LiFePO-IS-CDL/Li batteries present a capacity of 142.6 mA h g at 45 °C with the capacity retention of 91.7% after 100 cycles, and all-solid-state NCM811-IS-CDL/Li batteries deliver a specific capacity of 175.5 mA h g at 60 °C. This work proposes an effective strategy to fabricate all-solid-state lithium batteries with high electrochemical performance.
全固态电池已成为最具潜力的下一代储能装置。然而，要同时实现具有无枝晶锂金属镀层且阴极与固态电解质（SSEs）之间界面电阻低的单一固态电解质层是相当困难的。在此，设计了一种阴极与双层固体电解质膜的集成结构（IS-CDL），它极大地改善了界面接触并抑制了锂枝晶生长。第一个“陶瓷中的聚合物”固态电解质层（SL1）由80 wt%的LiAlTi(PO)（LATP）纳米颗粒和20 wt%的聚环氧乙烷（PEO）组成，第二个聚合物电解质层是基于PEO的固态电解质层（SL2）。具有高机械性能的SL1可以阻碍锂枝晶的生长并降低与阴极的界面电阻。SL2可以抑制锂金属与LATP之间的副反应。具有三明治型分级电解质（SL2/SL1/SL2）的锂对称电池在45℃下以0.1 mA cm可稳定循环超过3200小时。所制备的全固态LiFePO-IS-CDL/Li电池在45℃下容量为142.6 mA h g，100次循环后容量保持率为91.7%，全固态NCM811-IS-CDL/Li电池在60℃下的比容量为175.5 mA h g。这项工作提出了一种制备具有高电化学性能的全固态锂电池的有效策略。
