Self-Assembly Monolayer Inspired Stable Artificial Solid Electrolyte Interphase Design for Next-Generation Lithium Metal Batteries

Abstract

Lithium metal is widely regarded as the "ultimate" anode for energy-dense Li batteries, but its high reactivity and delicate interface make it prone to dendrite formation, limiting its practical use. Inspired by self-assembled monolayers on metal surfaces, we propose a facile yet effective strategy to stabilize Li metal anodes by creating an artificial solid electrolyte interphase (SEI). Our method involves dip-coating Li metal in MPDMS to create an SEI layer that is rich in inorganic components, allowing uniform Li plating/stripping under a low overpotential over 500 cycles in carbonate electrolytes. In comparison, pristine Li metal shows a rapid increase in overpotential after merely 300 cycles, leading to failure soon after. Molecular dynamics simulations demonstrate that this uniform artificial SEI suppresses Li dendrite formation. We further demonstrated its enhanced stability pairing with LiFePO 4 and LiNi 1−x−y Co x Mn y O 2 cathodes, highlighting the proposed strategy as a promising solution for practical Li metal batteries.

Fatigue-Free and Skin-like Supramolecular Ion-Conductive Elastomeric Interphases for Stable Lithium Metal Batteries

“…One routine way is to promote in situ formation of a stable SEI layer by optimizing the electrolytes, including sacrificial additives, highly concentrated electrolytes, and fluorinated electrolytes . Nevertheless, the so-formed SEI continuously grows by constantly consuming the electrolyte solvents, salt anions, or sacrificial additives in the electrolyte, making it difficult to modulate the composition and structure of the SEI. − Accordingly, the improvement in cycling stability by using a large excess of electrolyte inevitably compromises the energy density of batteries. Another approach is to replace the electrolyte-derived SEI by ex-situ formed artificial SEI layers such as inorganic materials (for example, Li 3 PO 4 , LiF, Li 2 S), organic polymers (for example, polyrotaxane- co -poly­(acrylic acid) (PR–PAA), P­(St-MaI), polydimethylsiloxane, and copolymer of poly­(ethylene glycol) methyl ether methacrylate and 2-[3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2-yl)­ureido]­ethyl methacrylate), and organic–inorganic composites. − However, ionic insulation or poor ionic conductivity would definitely retard the Li + transfer across the interface, resulting in increased polarization and dendrite growth .…”

Porous, robust, thermally stable, and flame retardant nanocellulose/polyimide separators for safe lithium-ion batteries

“…This approach provides PI separators with interlinked and wide pores, facilitating Li + migration. But these extended pores can easily lead to micro-short circuits stemming from Li dendrite growth 18–21 and the inferior binding force among the electrospun PI fibers results in unsatisfactory mechanical properties. 22–24 Although some efforts were made to improve the strength through doping inorganic nanoparticles, adding binders, or hot pressing, 16,25,26 no satisfactory results were achieved.…”

Functional nanolayers favor the stability of solid-electrolyte-interphase in rechargeable batteries

“…Metal anodes are widely considered the "ultimate" anode for high energy density rechargeable batteries, especially the "holy grail" Li metal anode. The main challenge for Li metal anode used in batteries is the dendrite formation because of the uncontrolled Li plating/stripping [22,23] . Li et al coated Li metal with 3-mercaptopropylmethyldimethoxysilane (MPDMS) protective monolayers as an artificial SEI by a [18] , Copyright 2023, Springer Nature.…”