A Multifunctional Silicon‐Doped Polyether Network for Double Stable Interfaces in Quasi‐Solid‐State Lithium Metal Batteries

Abstract

are difficult to be simultaneously compatible with Li metal anode with a strong reducibility and metal-oxide cathode with high oxidizability. [9][10][11] The most effective strategy to solve the above-mentioned problems is the formation of stable solidelectrolyte-interface (SEI) layer between electrolyte and anode/cathode. [12][13][14] Therefore, the development of polymer-based QSE that can form the stable SEI layers on anode and cathode have great potential to improve the cyclic stability and safety of Li-metal batteries. [15][16][17] Great efforts have been done on the structure in regulation of polymer-based electrolyte to construct the stable SEI layer on anode, such as co-polymerization, [18,19] cross-linking, [20,21] blending, [8,22] plasticizing, [23] and adding inorganic materials. [24] For example, Wu et al. reported a quasi-solid-state polymer-brush electrolytes with robust strength and single lithium-ion conduction to realize the dendrite-free Li-metal batteries. [25] Compared with general polymer-based electrolyte, [26,27] the above strategies can effectively improve the mechanical strength to inhibit the growth of lithium dendrite for the increased stability of anode. [28][29][30] At cathode/electrolyte interface, the introduction of artificially inorganic/polymeric layers is a general and effective strategy to improve the stability. [17,31] For example, Choudhury et al. reported lithium's semi-crystalline anionic polymer electrolyte to coat the cathode to improve cyclic stability of high-voltage oxide materials. [2] Although the aforementioned strategies show their advantages for improving the cyclic stability of anode/ cathode, they still cannot concurrently meet the high requirements of stable interfaces for both high oxidation cathode and reduction anode. [33,34] Additionally, the mobility of present gel polymer electrolyte (GPE) has improved as the temperature increases, which limits the safety performance of batteries. [35,36] Therefore, the development of new strategy that simultaneously meets the requirements of QSE with high safety, the formation of SEI layers with resistance to high oxidation and reduction potentials, and is the key to the construction of highperformance lithium-metal batteries. [37][38][39] In this study, we first demonstrate that a silicon-doped polyether (Silicon, ≈10 wt%) can act as a multifunctional unit Polymer-based quasi-solid-state electrolyte (QSE) is an effective means to solve the safety problem of lithium (Li) metal batteries, and stable solidelectrolyte-interface (SEI) layers between electrolyte and anode/cathode are highly required for their long-term stability. Herein, it is demonstrated that a silicon-doped polyether functions as a multifunctional unit, which can induce the formation of stable and robust SEI layers with rich Li x SiO y on both the surfaces of cathode and anode. It simultaneously solves the compatibility of electrolyte and electrodes in the quasi-solid-state Li-metal battery. Moreover, the robust polymer skeleton with a cross-linked network...

In Situ Construction of Gradient Oxygen Release Buffer and Interface Cation Self‐Accelerator Stabilizing High‐Voltage Ni‐Rich Cathode

“…[1] The detrimental oxygen release upon repeated cycling would induce irreversible structural transformation and fast capacity fading as well as severe safety concerns. [26] The results herein clearly confirmed that the LBO modification could stabilize the lattice O in Ni-rich cathode, consistent with the above-mentioned theoretical calculations (Figure 1b-e).…”

A jigsaw-structured artificial solid electrolyte interphase for high-voltage lithium metal batteries

“…In accordance with this point, competitive silica-containing organic artificial SEIs, such as silicates 24,25 , polydimethylsiloxane 7,26 , silane coupling agent 27 , and some silica composites [28][29][30][31][32] , show great potential for stabilizing LMAs with desirable features, such as good mechanic strength, lithiophilicity, and air tolerance. The high-modulus character of silica-containing artificial SEI can mechanically suppress the Li dendrite growth, the distinct lithiophilicity can regulate Li + flux to smoothen Li + deposition, and air tolerance of LMAs dramatically simplify the fabrication process [33][34][35][36][37][38] .…”

In situconstruction of polyether-based composite electrolyte with bi-phase ion conductivity and stable electrolyte/electrode interphase for solid-state lithium metal batteries

“…Meanwhile, the PDOL phase permeated in LLTO can achieve rapid ion conduction through the coupling/decoupling of O and Li + in the -CH 2 -CH 2 -O-CH 2 -Opolymer chains. 13,28 To further analyze the topochemistry of PDOL, nuclear magnetic resonance (NMR) measurements were performed (Fig. 1e).…”

“…Meanwhile, the PDOL phase permeated in LLTO can achieve rapid ion conduction through the coupling/decoupling of O and Li + in the –CH 2 –CH 2 –O–CH 2 –O– polymer chains. 13,28…”