Crack Suppression by Downsizing Sulfide‐Electrolyte Particles for High‐Current‐Density Operation of Metal/Alloy Anodes

Abstract

Stable physical contact between lithium metal/alloy anodes and the solid electrolyte layer is crucial for the durable operation of allsolid‐state batteries. Herein, we have attempted to control the mechanical property of a Li10.35Ge1.35P1.65S12 (LGPS) solid electrolyte layer by the grain size and examined the mechanical strength against stresses originating from volumetric changes of an In‐Li anode layer. The submicron‐sized LGPS electrolyte (d50: 0.51 µm) with a uniform particle size distribution has successfully fabricated by a wet‐milling process. The crystallinity of LGPS hardly changes on pulverization. In‐Li symmetric cells with the wet‐milled LGPS exhibits better cycle stability than those constructed with micro‐sized LGPS (d50: 1.32 µm) that is not well controlled by particle size, owing to a greater suppression of overvoltage generation and growth. Microstructural analyses have revealed that the small and uniform LGPS particles are less prone to physical degradation (cracking) due to volume changes of In‐Li. Downsizing of solid electrolytes is a good strategy for developing physically stable electrode/solid electrolyte interfaces even at high current density operation.

Review—Recent Advancements in Sulfide Solid Electrolytes for All-Solid-State Lithium-Sulfur Batteries

“…31 In addition, it was proven that the particle size distribution is greatly affecting the result performance of the electrolyte. 32,33 On the base of Li 10.35 Ge 1.35 P 1.65 S 12 electrolyte, it was found that the incensement of the hand grounding time from 5 to 30 min allows both decrees the average particle size and narrower the size distribution. As a result, the resulting symmetrical lithium cell has a longer cycling life and the mechanical degradation of the electrolyte is suppressed.…”

“…As a result, the resulting symmetrical lithium cell has a longer cycling life and the mechanical degradation of the electrolyte is suppressed. 32 In general, the solid-state synthesis is not only universal but also easily scalable and adjustable. Notably, it is solvent-free, which eliminates issues associated with solvent use, such as the release of volatile organic compounds and the need for additional disposal procedures that could negatively impact the environment.…”

“…However, when the process requires annealing of the starting materials, it demands high temperatures (typically above 500 °C) and prolonged reaction times (about 7-8 h), leading to significant energy consumption. 23,32,34 Nevertheless, the main disadvantage of this synthetic way is that there is no possibility of controlling the reaction process in the milling jar. In addition, the starting reagent can stick to the milling ball, which in turns will lead to the stoichiometry disturbance and subsequent formation of the by-products.…”

Technological Advances and Market Developments of Solid-State Batteries: A Review

“…Interface reactions could influence long-term battery performance and cycling stability [ 59 ]. Moreover, LGPS and similar solid electrolyte materials can be brittle with inferior mechanical properties, potentially resulting in issues like cracking or delamination during battery fabrication and operation [ 60 ]. Additionally, the hygroscopic nature of LGPS requires meticulous handling and storage practices to prevent moisture absorption, which could compromise its performance.…”

Fabrication and High-temperature Electrochemical Stability of LiFePO₄ Cathode/Li₃PO₄ Electrolyte Interface

“…To enhance the reaction rate of lithium desertion/insertion, the cathodes in bulk-type all-solid-state batteries are composed of an active material and solid electrolyte. Although appropriate particle sizes of the active material and solid electrolyte have been extensively investigated, [13][14][15] it is of technical difficulty to fabricate a highly dispersed composite electrode exhibiting minimal aggregation using nanosized particles of the active materials, due to their high surface energy. [16][17][18] Thus, there are far fewer studies on the electrochemical behavior of LiFePO 4 in all-solid-state batteries than those on LiMO 2 and LiMn 2 O 4 cathodes.…”