Abstract
This study illustrates how the microstructure of garnet solid-state electrolytes (SSE) affects the stress-state and dendrite growth. Tantalum-doped lithium lanthanum zirconium oxide (LLZTO, Li6.4La3Zr1.4Ta0.6O12) is synthesized by powder processing and sintering (AS), or with the incorporation of intermediate-stage high-energy milling (M). The M compact displays higher density (91.5% vs 82.5% of theoretical), and per quantitative stereology, lower average grain size (5.4 ± 2.6 vs 21.3 ± 11.1 µm) and lower AFM-derived RMS surface roughness contacting the Li metal (45 vs 161 nm). These differences enable symmetric M cells to electrochemically cycle at constant capacity (0.1 mAh cm−2) with enhanced critical current density (CCD) of 1.4 versus 0.3 mA cm−2. It is demonstrated that LLZTO grain size distribution and internal porosity critically affect electrical short-circuit failure, indicating the importance of electronic properties. Lithium dendrites propagate intergranularly through regions where LLZTO grains are smaller than the bulk average (7.4 ± 3.8 µm for AS in a symmetric cell, 3.1 ± 1.4 µm for M in a half-cell). Metal also accumulates in the otherwise empty pores of the sintered compact present along the dendrite path. Mechanistic modeling indicates that reaction and stress heterogeneities are interrelated, leading to current focusing and preferential plating at grain boundaries.
| Original language | English |
|---|---|
| Article number | 2303062 |
| Journal | Advanced Energy Materials |
| Volume | 14 |
| Issue number | 15 |
| DOIs | |
| State | Published - Apr 19 2024 |
| Externally published | Yes |
Funding
V.R., K.G.N., B.S.V., P.P.M. and D.M. are supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award # DE-SC0023260. N.B.P.A is supported by Department of Science and Technology, Government of India under program DST-IISc MECSP-2K17 (grant no. DST/TMD/MECSP/2K17/20) and by Department of Heavy Industries (DHI), India (Ref: No 7(14)/2019-AEI (21025). N.P.B.A. acknowledges the new faculty start-up grant (no. 12-0205-0618-77) provided by the Indian Institute of Science (IISc). Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC (NTESS), a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy's National Nuclear Security Administration (DOE/NNSA) under contract DE-NA0003525. This written work is authored by an employee of NTESS. The employee, not NTESS, owns the right, title and interest in and to the written work and is responsible for its contents. Any subjective views or opinions that might be expressed in the written work do not necessarily represent the views of the U.S. Government. The publisher acknowledges that the U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this written work or allow others to do so, for U.S. Government purposes. The DOE will provide public access to results of federally sponsored research in accordance with the DOE Public Access Plan. V.R., K.G.N., B.S.V., P.P.M. and D.M. are supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award # DE‐SC0023260. N.B.P.A is supported by Department of Science and Technology, Government of India under program DST‐IISc MECSP‐2K17 (grant no. DST/TMD/MECSP/2K17/20) and by Department of Heavy Industries (DHI), India (Ref: No 7(14)/2019‐AEI (21025). N.P.B.A. acknowledges the new faculty start‐up grant (no. 12‐0205‐0618‐77) provided by the Indian Institute of Science (IISc). Sandia National Laboratories is a multi‐mission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC (NTESS), a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy's National Nuclear Security Administration (DOE/NNSA) under contract DE‐NA0003525. This written work is authored by an employee of NTESS. The employee, not NTESS, owns the right, title and interest in and to the written work and is responsible for its contents. Any subjective views or opinions that might be expressed in the written work do not necessarily represent the views of the U.S. Government. The publisher acknowledges that the U.S. Government retains a non‐exclusive, paid‐up, irrevocable, world‐wide license to publish or reproduce the published form of this written work or allow others to do so, for U.S. Government purposes. The DOE will provide public access to results of federally sponsored research in accordance with the DOE Public Access Plan.
Keywords
- LLZO
- all solid-state battery (ASSB)
- chemo-mechanical
- electrochemical–mechanical
- metal dendrite
- oxide electrolyte