A Liquid/Liquid Electrolyte Interface that Inhibits Corrosion and Dendrite Growth of Lithium in Lithium‐Metal Batteries

Abstract

A proof‐of‐concept study on a liquid/liquid (L/L) two‐phase electrolyte interface is reported by using the polarity difference of solvent for the protection of Li‐metal anode with long‐term operation over 2000 h. The L/L electrolyte interface constructed by non‐polar fluorosilicane (PFTOS) and conventionally polar dimethyl sulfoxide solvents can block direct contact between conventional electrolyte and Li anode, and consequently their side reactions can be significantly eliminated. Moreover, the homogeneous Li‐ion flow and Li‐mass deposition can be realized by the formation of a thin and uniform solid‐electrolyte interphase (SEI) composed of LiF, LixC, LixSiOy between PFTOS and Li anode, as well as the super‐wettability state of PFTOS to Li anode, resulting in the suppression of Li dendrite formation. The cycling stability in a lithium–oxygen battery as a model is improved 4 times with the L/L electrolyte interface.

Lithium Nitrate Regulated Sulfone Electrolytes for Lithium Metal Batteries

“…[4] However,t he low plating/stripping Coulombic efficiency (CE) of Li anodes and lithium dendrite growth in carbonate electrolytes limits the cycle life. [5] Extensive efforts have been devoted to protecting the lithium metal anodes by using artificial solid electrolyte interface (ASEI) layers, [6] nano-structure 3D Li anodes, [7] liquid electrolyte design to form inorganic solid electrolyte interface (SEI), [8] and polymer or inorganic solid-state electrolytes. [9] Among them, the most effective method is to form an inorganic solid electrolyte interface (SEI) on Li anodes because the inorganic SEI has ahigher interface energy with Li than organic SEI.…”

Anode interface modification of lithium metal batteries: Benefiting from functional additives and conformal coatings

“…Copyright © 2019, WILEY-VCH. (d) Scheme of Li dendrite growth and suppression effect in conventional electrolyte or liquid-liquid (L/ L) two-phase electrolyte [44] . Copyright © 2020, WILEY-VCH…”

Design Parameters for Ionic Liquid–Molecular Solvent Blend Electrolytes to Enable Stable Li Metal Cycling Within Li–O2 Batteries

“…[ 16 ] A recent proof‐of‐concept investigation also demonstrated the use of a liquid/liquid interface with a secondary non‐soluble electrolyte to enhance stability by blocking direct DMSO‐Li 0 interaction. [ 17 ] Similarly, the performance of N , N ‐dimethylacetamide, a solvent with comparable reactivity at Li 0 , was shown to be improved in Li–O 2 full cells with careful optimization of the salt composition at high concentrations to regulate the formation of a beneficial SEI. [ 18 ]…”