TY - JOUR
T1 - Mechanical Milling – Induced Microstructure Changes in Argyrodite LPSCl Solid-State Electrolyte Critically Affect Electrochemical Stability
AU - Wang, Yixian
AU - Hao, Hongchang
AU - Naik, Kaustubh G.
AU - Vishnugopi, Bairav S.
AU - Fincher, Cole D.
AU - Yan, Qianqian
AU - Raj, Vikalp
AU - Celio, Hugo
AU - Yang, Guang
AU - Fang, Hong
AU - Chiang, Yet Ming
AU - Perras, Frédéric A.
AU - Jena, Puru
AU - Watt, John
AU - Mukherjee, Partha P.
AU - Mitlin, David
N1 - Publisher Copyright:
© 2024 Wiley-VCH GmbH.
PY - 2024/6/19
Y1 - 2024/6/19
N2 - Microstructure of argyrodite solid-state electrolyte (SSE) critically affects lithium metal electrodeposition/dissolution. While the stability of unmodified SSE is mediocre, once optimized state-of-the-art electrochemical performance is achieved (symmetric cells, full cells with NMC811) without secondary interlayers or functionalized current collectors. Planetary mechanical milling in wet media (m-xylene) is employed to alter commercial Li6PS5Cl (LPSCl) powder. Quantitative stereology demonstrates how milling progressively refines grain and pore size/distribution in the SSE compact, increases its density, and geometrically smoothens the SSE-Li interface. Mechanical indentation demonstrates that these changes lead to reduced site-to-site variation in the compact's hardness. Milled microstructures promote uniform early-stage electrodeposition on foil collectors and stabilize solid electrolyte interphase (SEI) reactivity. Analysis of half-cells with bilayer electrolytes demonstrates the importance of microstructure directly contacting current collector, with interface roughness due to pore and grain size distribution being key. For the first time, short-circuiting Li metal dendrite is directly identified, employing 1.5 mm diameter “mini” symmetrical cell and cryogenic focused ion beam (cryo-FIB) electron microscopy. The branching sheet-like dendrite traverses intergranularly, filling the interparticle voids and forming an SEI around it. Mesoscale modeling reveals the relationship between Li-SSE interface morphology and the onset of electrochemical instability, based on underlying reaction current distribution.
AB - Microstructure of argyrodite solid-state electrolyte (SSE) critically affects lithium metal electrodeposition/dissolution. While the stability of unmodified SSE is mediocre, once optimized state-of-the-art electrochemical performance is achieved (symmetric cells, full cells with NMC811) without secondary interlayers or functionalized current collectors. Planetary mechanical milling in wet media (m-xylene) is employed to alter commercial Li6PS5Cl (LPSCl) powder. Quantitative stereology demonstrates how milling progressively refines grain and pore size/distribution in the SSE compact, increases its density, and geometrically smoothens the SSE-Li interface. Mechanical indentation demonstrates that these changes lead to reduced site-to-site variation in the compact's hardness. Milled microstructures promote uniform early-stage electrodeposition on foil collectors and stabilize solid electrolyte interphase (SEI) reactivity. Analysis of half-cells with bilayer electrolytes demonstrates the importance of microstructure directly contacting current collector, with interface roughness due to pore and grain size distribution being key. For the first time, short-circuiting Li metal dendrite is directly identified, employing 1.5 mm diameter “mini” symmetrical cell and cryogenic focused ion beam (cryo-FIB) electron microscopy. The branching sheet-like dendrite traverses intergranularly, filling the interparticle voids and forming an SEI around it. Mesoscale modeling reveals the relationship between Li-SSE interface morphology and the onset of electrochemical instability, based on underlying reaction current distribution.
KW - argyrodite
KW - chemo-mechanical
KW - dendrite
KW - inorganic solid electrolytes
KW - solid-state battery
UR - http://www.scopus.com/inward/record.url?scp=85190164738&partnerID=8YFLogxK
U2 - 10.1002/aenm.202304530
DO - 10.1002/aenm.202304530
M3 - Article
AN - SCOPUS:85190164738
SN - 1614-6832
VL - 14
JO - Advanced Energy Materials
JF - Advanced Energy Materials
IS - 23
M1 - 2304530
ER -