In situ Observation of Li Deposition-Induced Cracking in Garnet Solid Electrolytes

Energy & Environmental Materials

article

Jun Zhao¹  Yongfu Tang¹  Qiushi Dai¹  Congcong Du¹  Yin Zhang³  Dingchuan Xue⁴  Tianwu Chen⁴  Jianyu Huang¹  Jingzhao Chen¹  Bo Wang¹  Jingming Yao¹  Ning Zhao⁶  Yanshuai Li¹  Shuman Xia³  Xiangxin Guo⁶  Stephen J. Harris⁷  Liqiang Zhang¹  Sulin Zhang⁴  Ting Zhu³ 

[1] Clean Nano Energy Center, State Key Laboratory of Metastable Materials Science and Technology, Yanshan University;Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University;Woodruff School of Mechanical Engineering, Georgia Institute of Technology;Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park;School of Materials Science and Engineering, Xiangtan University;College of Physics, Qingdao University;Energy Storage Division, Lawrence Berkeley, National Laboratory

关键词: cracking;    garnet solid electrolyte;    in situ observation;    Li deposition;   

DOI  :  10.1002/eem2.12261

来源: Wiley

【 摘 要 】

Lithium (Li) penetration through solid electrolytes (SEs) induces short circuits in Li solid-state batteries (SSBs), which is a critical issue that hinders the development of high energy density SSBs. While cracking in ceramic SEs has been often shown to accompany Li penetration, the interplay between Li deposition and cracking remains elusive. Here, we constructed a mesoscale SSB inside a focused ion beam-scanning electron microscope (FIB-SEM) for in situ observation of Li deposition-induced cracking in SEs at nanometer resolution. Our results revealed that Li propagated predominantly along transgranular cracks in a garnet Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO). Cracks appeared to initiate from the interior of LLZTO beneath the electrode surface and then propagated by curving toward the LLZTO surface. The resulting bowl-shaped cracks resemble those from hydraulic fracture caused by high fluid pressure on the surface of internal cracks, suggesting that the Li deposition-induced pressure is the major driving force of crack initiation and propagation. The high pressure generated by Li deposition is further supported by in situ observation of the flow of filled Li between the crack flanks, causing crack widening and propagation. This work unveils the dynamic interplay between Li deposition and cracking in SEs and provides insight into the mitigation of Li dendrite penetration in SSBs.

【 授权许可】

Unknown