Chemical Heterogeneity in PAN/LLZTO Composite Electrolytes by Synchrotron Imaging

Abstract

Solid polymer/ceramic composite electrolytes are promising for batteries due to their attractive thermal stability and mechanical properties. Chemical heterogeneity in solid composite electrolytes, such as the inhomogeneity in the ceramic phase and salt distribution at the polymer/ceramic interface, is critical to the performance of solid composite electrolytes. However, such heterogeneity has not been well understood yet. In this work, we use Synchrotron-based X-ray fluorescence imaging (XRF) and Transmission X-ray Microscope (TXM) to image nanoscale chemical heterogeneity in polyacrylamide/Li7+xLa3Zr2−xTaxO12 (LLZTO) composite electrolytes and investigate the effects of lithium salt, salt concentration, and plasticizer. We find that LLZTO particles show strong inter- and intra-particles chemical heterogeneities, and the off-stoichiometry of Zr in an LLZTO particle is unlikely to be only balanced by Ta substitution. Moreover, statistical analysis suggests that LiI tends to accumulate at the ceramic/polymer interface at a low concentration of 5 wt%, but no such tendency was observed in samples with 10 wt% LiI. However, composite electrolytes with LiTFSI show interfacial accumulation at both 5 wt% and 10 wt%. This report provides insight into element distributions in solid composite electrolytes, and we hope further researches can shed light on the connections between chemical heterogeneity and ionic transport pathway inside.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 01, 2021
Source ID
10.1149/1945-7111/ac352a

Entities

People

  • Chunrun Chen
  • Ruiwen Zhang
  • Shuaifeng Lou
  • Tianwei Jin
  • Tianze Xu
  • Xianghui Xiao
  • Xiaojing Huang
  • Yuan Yang

Organizations

  • Air Force Office of Scientific Research

Tags

Fields of Study

  • Materials science

Readers

  • Medical Imaging.
  • Reinforced Composite Materials
  • Surface Engineering/Surface Coating Technology.