A Two-Parameter Space to Tune Solid Electrolytes for Lithium Dendrite Constriction

Abstract

Li dendrite penetration, and associated microcrack propagation, at high current densities is one main challenge to the stable cycling of solid-state batteries. The interfacial decomposition reaction between Li dendrite and a solid electrolyte was recently used to suppress Li dendrite penetration through a novel effect of “dynamic stability”. Here we use a two-parameter space to classify electrolytes and propose that the effect may require the electrolyte to occupy a certain region in the space, with the principle of delicately balancing the two property metrics of a sufficient decomposition energy with the Li metal and a low critical mechanical modulus. Furthermore, in our computational prediction prepared using a combination of high-throughput computation and machine learning, we show that the positions of electrolytes in such a space can be controlled by the chemical composition of the electrolyte; the compositions can also be attained by experimental synthesis using core–shell microstructures. The designed electrolytes following this principle further demonstrate stable long cycling from 10 000 to 20 000 cycles at high current densities of 8.6–30 mA/cm 2 in solid-state batteries, while in contrast the control electrolyte with a nonideal position in the two-parameter space showed a capacity decay that was faster by at least an order of magnitude due to Li dendrite penetration.

Effect of Solvents on a Li10GeP2S12-Based Composite Electrolyte via Solution Method for Solid-State Battery Applications

“…Note that 10 nm of the SiO 2 reference sample was sputtered away. Since SiO 2 (∼36 GPa) shows a bulk modulus similar to that of LGPS (∼30 GPa), , we estimate that they should show similar Ar + etching speed following a previous argument; thus, the depth of this residue layer from decomposition reaction is estimated to be around 10 nm.…”

Anharmonic Cation–Anion Coupling Dynamics Assisted Lithium‐Ion Diffusion in Sulfide Solid Electrolytes

“…Sulfide‐based lithium ionic conductors often show higher ionic conductivities than the oxides and organic polymers and have excellent mechanical properties for compatibility with scaling‐up engineering procedures, negligible grain‐boundary resistance, and synthesis convenience at low temperature. [ 1–3 ] Therefore, the sulfide‐based lithium ionic conductors are promising solid‐state electrolyte materials to replace the commercial liquid electrolytes and polymer separators, which may also effectively combine with lithium metal anode without dendrite penetration, [ 4,5 ] increasing the safety and energy density of solid‐state batteries.…”

“…DOI: 10.1002/adma.202207411 penetration, [4,5] increasing the safety and energy density of solid-state batteries.…”

Interfacial Behavior of a Thio-LISICON Solid-State Electrolyte under External Pressure

“…Consequently, stable cycling of commonly believed unstable sulfide electrolytes can be attained. Improved interface stability can also be realized with a core–shell microstructure of SSE particles. − With a thin amorphous shell of the SSE material (∼20 nm) that does not undergo significant volume expansion upon decomposition, the mechanical constraints on the core SSE improves its thermodynamic stability.…”