| AVS 64th International Symposium & Exhibition | |
| Sustainability Focus Topic | Tuesday Sessions |
| Session SU+AC+MI+MS-TuM |
| Session: | Critical Materials and Energy Sustainability |
| Presenter: | Alexander Yulaev, University of Maryland |
| Authors: | A. Yulaev, University of Maryland V. Oleshko, NIST P. Haney, NIST Center for Nanoscale Science and Technology A.A. Talin, Sandia National Laboratories M.S. Leite, University of Maryland A. Kolmakov, NIST Center for Nanoscale Science and Technology |
| Correspondent: | Click to Email |
The recent progress in all-solid-state Li-ion batteries (SSLIBs) allowed a significant reduction of overall dimensions of stand-alone medical and micro-electronic devices. Owing to their compatibility with microfabrication process, high specific power, energy densities, and reduced safety risks of the thermal runaway, SSLIBs are likely to compete with their liquid counterparts in the near future. However, the large-scale implementation of SSLIBs requires further characterization during their fabrication and operation. Particularly, spatially resolved in-operando techniques probing electrochemical processes at the interfaces are needed. In the present work, we quantify the effects of oxidizing environment and charging rates on a lithium plating morphology using UHV electron microscopy and spectroscopy in correlation with electrochemical characterization. To conduct these measurements, we fabricate a model thin-film planar battery with LiCoO2 cathode, LiPON electrolyte, and an ultra-thin carbon anode. Our experimental data reveal a strong dependence of plated Li morphology on presence of oxidation species at the surface and a gas phase. Under UHV conditions a linear correlation between the nucleation density of lithium clusters and a charging rate is observed. We show that the 2D nucleation model adequately describes the obtained dependence. The plated lithium morphology drastically changes from the in-plane clusters to out-of-plane whisker growth when ~10-7 Pa of oxygen is admitted to the UHV chamber. The in-plane cluster growth resumes when oxygen pressure increases from 10-7 to 10-5 Pa. We envision that our findings will contribute to whisker-free safer SSLIB performance under realistic operating conditions.