New Amorphous Oxy-Sulfide Solid Electrolyte Material: Anion Exchange, Electrochemical Properties, and Lithium Dendrite Suppression via In Situ Interfacial Modification

Abstract

Glassy sulfide materials have been considered as promising candidates for solid-state electrolytes (SSEs) in lithium and sodium metal (LM and SM) batteries. While much of the current research on lithium glassy SSEs (GSSEs) has focused on the pure sulfide binary Li2S + P2S5 system, we have expanded these efforts by examining mixed-glass-former (MGF) compositions which have mixtures of glass formers, such as P and Si, which allow melt-quenching synthesis under ambient pressure and therefore the use of grain-boundary-free SSEs. We have doped these MGF compositions with oxygen to improve the chemical, electrochemical, and thermal properties of these glasses. In this work, we report on the short-range order (SRO), namely atomic-level, structures of Li2S + SiS2 + P2O5 MGF mixed oxy-sulfide glasses and, for the first time, study the critical current density (CCD) of these Si-doped oxy-sulfide GSSEs in LM symmetric cells. The samples were synthesized by planetary ball milling (PBM), and it was observed that a certain minimum milling time was necessary to achieve a final SRO structure. To address the short-circuiting lithium dendrite (LD) problems that were observed in these GSSEs, we demonstrate a simple and novel strategy for these Si-doped oxy-sulfide GSSEs to engineer the LM–GSSE interface by forming an in situ interlayer via heat treatment. Stable cycling to ∼1200 h at a capacity of 2 mAh·cm–2 per discharge/charge cycle under a current density of 1 mA·cm–2 is achieved. These results indicate that these MGF oxy-sulfide GSSEs combined with an optimized interfacial modification may find use in LM, and by extrapolation, SM, batteries.

Defective Boron Nitride Inducing the Lithium‐ion Migration on the Sub‐Surface of LiBH4

“…The cell displayed a pair of representative charge-discharge curves in the first cycle with initial Coulombic efficiency (CE) of 287%, followed by CE of 98% during the subsequent cycle. As in the previous study, [58] the low initial discharge capacity (101 mA h g -1 ) results from the self-discharge reaction between TiS 2 and LiBH 4 /2(d-BN) during the process of the mixture, while the initial high charge capacity exceeding the theoretical value (290 mA h g -1 ) is due to the irreversible side reaction between them. Then, the cell delivered stable cycles with a reversible capacity of more than 200 mA h g -1 at 0.1 C and a capacity retention ratio of 83% (compared with the second cycle) after 30 cycles (Figure 7c).…”

Enhancing Moisture Stability of Sulfide Solid-State Electrolytes by Reversible Amphipathic Molecular Coating

“…The development of all-solid-state batteries (ASSBs) using inorganic solid-state electrolytes (SSEs) is being pursued intensively because these batteries are one of the promising candidates for next-generation energy storage technology given their high potential to achieve high energy/power densities and superior safety. − High-performance SSEs, such as sulfides, oxides, and polymer-based electrolytes, are crucial to the success of ASSB development. − Among the SSEs, sulfides are more promising because of their soft nature and high ionic conductivities at room temperature, ensuring good SSE/electrode materials contact and fast Li-ion conduction. − However, the poor moisture stability of sulfide SSEs associated with the generation of highly toxic H 2 S gas hinders their processing and applications in large-scale production. − To address this critical issue, several strategies have been tentatively suggested in the literature. One is to combine inorganic H 2 S absorption additives (such as Fe 2 O 3 , ZnO, and Bi 2 O 3 ) with SSEs to chemically consume the generated H 2 S .…”

Synthesis and Growth Mechanism of SiS2 Rods

“…Silicon disulfide (SiS 2 ) is an important synthetic compound used in fundamental and applied research. It is one of the important raw materials for sulfide-based solid electrolytes. − There are five polymorphs of SiS 2 . One is the ambient-pressure (NP) phase (≤3.83 MPa, 973–1570 K) ,,− with an orthorhombic structure ( Ibam , Space Group no.…”