Effect of current density on the solid electrolyte interphase formation at the lithium∣Li6PS5Cl interface

Abstract

Understanding the chemical composition and morphological evolution of the solid electrolyte interphase (SEI) formed at the interface between the lithium metal electrode and an inorganic solid-state electrolyte is crucial for developing reliable all-solid-state lithium batteries. To better understand the interaction between these cell components, we carry out X-ray photoemission spectroscopy (XPS) measurements during lithium plating on the surface of a Li6PS5Cl solid-state electrolyte pellet using an electron beam. The analyses of the XPS data highlight the role of Li plating current density on the evolution of a uniform and ionically conductive (i.e., Li3P-rich) SEI capable of decreasing the electrode∣solid electrolyte interfacial resistance. The XPS findings are validated via electrochemical impedance spectrsocopy measurements of all-solid-state lithium-based cells.

Operando Characterization and Theoretical Modeling of Metal|Electrolyte Interphase Growth Kinetics in Solid-State Batteries. Part I: Experiments

“…In other words, the evolution of the peak positions confirms that the interphase forms over a longer period for the Na 0 |NZSP polished interface in comparison to the Na 0 |Na x PO y |NZSP interface. We invite the reader to refer to Part II of this study for more a more in-depth discussion on the origin of these peak shifts …”

“…We invite the reader to refer to Part II of this study for more a more in-depth discussion on the origin of these peak shifts. 12 Aging Dynamics of Na 0 |NZSP Interfaces by Electrochemical Impedance Spectroscopy (EIS). The operando XPS experiments established the protecting role of the thin Na x PO y layer on the surface of NZSP AS samples against the formation of a thick SEI upon contact with Na 0 .…”

“…What enables the plating in that case is the provision of low-energy electrons to the surface of the SE from the electron flood gun present in any XPS instrument. This operando XPS technique has the additional benefit of replicating the conditions which occur during the first charge of cells with zero excess capacity on the negative electrode (also sometimes referred to as “anode-free” cells) . While this technique has already proven its efficacy at characterizing the composition of interphases, the extent of information that can be extracted from it (such as the growth rate behavior of the alkali metal layer) has not yet been fully appreciated.…”

“…This operando XPS technique has the additional benefit of replicating the conditions which occur during the first charge of cells with zero excess capacity on the negative electrode (also sometimes referred to as “anode-free” cells). 12 While this technique has already proven its efficacy at characterizing the composition of interphases, the extent of information that can be extracted from it (such as the growth rate behavior of the alkali metal layer) has not yet been fully appreciated. The objective of this study is to present the depth of information that can be extracted from this operando protocol.…”

Thin Solid Electrolyte Separators for Solid-State Lithium–Sulfur Batteries

“…The formation of Li 2 S is consistent with the reported components of the SEI between Li-metal and LPSCl. 24,25 Meanwhile, in the P 2p spectra, the formation of Li x P is difficult to observe, unlike in the SE pellet (Figure S2). These results demonstrate that the TSE forms a stable SEI in which Li 2 S was the dominant component in contact with Li-metal and was observably different from that formed with the SE pellet.…”