Percolated Sulfide in Salt‐Concentrated Polymer Matrices Extricating High‐Voltage All‐Solid‐State Lithium‐metal Batteries

Abstract

All‐solid‐state lithium‐metal batteries (ASLMBs) are considered to be remarkably promising energy storage devices owing to their high safety and energy density. However, the limitations of current solid electrolytes in oxidation stability and ion transport properties have emerged as fundamental barriers in practical applications. Herein, a novel solid electrolyte is presented by in situ polymerization of salt‐concentrated poly(ethylene glycol) diglycidyl ether (PEGDE) implanted with a three‐dimensional porous L10GeP2S12 skeleton to mitigate these issues. The poly(PEGDE) endows more oxygen atoms to coordinate with Li+, significantly lowering its highest occupied molecular orbital level. As a consequence, the electro‐oxidation resistance of poly(PEGDE) exceeds 4.7 V versus Li+/Li. Simultaneously, the three‐dimensonal porous L10GeP2S12 skeleton provides a percolated pathway for rapid Li+ migration, ensuring a sufficient ionic conductivity of 7.7 × 10−4 S cm−1 at room temperature. As the bottlenecks are well solved, 4.5 V LiNi0.8Mn0.1Co0.1O2‐based ASLMBs present fantastic cycle performance over 200 cycles with an average Coulombic efficiency exceeding 99.6% at room temperature.

Progress and perspectives of in situ polymerization method for lithium‐based batteries

“…Reproduced under the terms of the CC‐BY license. [ 141 ] Copyright 2022, the authors, published by Wiley‐VCH GmbH. (D) Scheme of the in situ polymerization in 3D LPSC skeleton.…”

“…By a similar process, porous LGPS 3D framework and PEGDE were also applied to CPEs. [ 141 ] The electrolyte performance was further improved with an electrochemical stability window of 4.7 V and an ionic conductivity of 7.7 × 10 − 4 S cm − 1 (Figure 12G,H).…”

“…Also, the polymer can act as a buffer layer between lithium metal and sulfide to inhibit the reduction of sulfide (Figure 12C). [141][142][143][144][145] By in situ polymerization, not only the gap between the electrode and electrolyte can be effectively filled, but also the internal pores of sulfide can be filled to form a dense CPE (Figure 12A,B).…”

A review on modified polymer composite electrolytes for solid-state lithium batteries

“…Multiplicative performance of these electrolytes can be obtained even comparable to that of lithium batteries with the PP separator (containing liquid electrolytes). Cui et al 122 obtained a novel CPE by in situ polymerization of high-salt polyethylene glycol diglycidyl ether (PEGDE) into a 3D porous Li 10 GeP 2 S 12 (LGPS) skeleton (Fig. 10e).…”

Chloride-Reinforced Solid Polymer Electrolyte for High-Performance Lithium Metal Batteries

“…Lithium metal batteries (LMBs) are considered to be the most promising rechargeable energy storage devices due to the low reduction potential and high energy density of the Li metal anode. − However, some serious issues, such as liquid electrolyte leakage or short circuiting caused by lithium dendrite penetration, impede the wide application of LMBs. Therefore, all-solid-state lithium batteries (ASSLBs) with solid electrolytes are being gradually developed to address these issues. − Inorganic solid-state electrolytes are widely appreciated for their high ionic conductivity and wide electrochemical window, but they suffer from unfavorable interfacial contact with electrodes . Polymer electrolytes with excellent flexibility can ensure compatibility between the electrode and electrolyte interface.…”