SEM Micromanipulator as Current Collector for Battery In-situ Characterization

Abstract

The aim of the work is to develop an in-situ method for electrode microstructure investigation by scanning electron microscopy (SEM). In the first part, the preparation of a model battery using FIB-SEM system is described, which consists of lithium metal, ionic liquid, and lithium titanate oxide (LTO) attached on a micromanipulation needle by platinum deposition. The needle is used for handling and at the same time as a current collector, which facilitates subsequent analysis. Open-circuit voltage (OCV), cyclic voltammetry (CV), and galvanostatic cycling measurements (GCPL) was done on the cell assembled (and imaged) in SEM. After seven complete cycles, a cross-section of LTO electrode using FIB was prepared and the surface solid electrolyte interface (SEI) layer was observed. Challenges connected with battery preparation are described and possible solutions for future testing are proposed. The work is evolved in cooperation with Thermo Fisher Scientific Brno.