Enhanced Cycling Performance of All‐Solid‐State Li‐S Battery Enabled by PVP‐Blended PEO‐Based Double‐Layer Electrolyte

Abstract

Despite the high specific capacity of LiÀ S battery, shuttle effect of lithium polysulfides (LiPSs) and safety issue pose a great challenge to realize its commercial application. Replacing liquid electrolyte with poly (ethylene oxide) (PEO) -based solid-state electrolyte is considered as a promising method to boost the safety, but the shuttle effect of LiPSs cannot be completely eliminated. In this work, a new kind of double-layer PEO-based polymer electrolyte is designed to restrict the LiPSs. The layer next to cathode consists of PEO and poly(vinylpyrrolidone) (PVP). The other layer consists of PEO. PVP with abundant of amide groups has been proved to have strong affinity to LiPSs. The strong interaction between LiPSs and carbonyl groups in amide is verified by Attenuated Total Reflection-Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy tests. As a result, the assembled LiÀ S battery exhibits a specific capacity of 1100 mAh g À 1 and capacity retention of 347 mAh g À 1 after 200 cycles at 60 °C and 0.05 C, while the capacity retention of the battery without PVP-blended PEO electrolyte remains only 27 % at the same conditions.

Regulate transportation of ions and polysulfides in all–solid-state Li-S batteries using ordered-MOF composite solid electrolyte

“…Moreover, the 3D MPPL CSEbased ASSLSBs in this work deliver a superior retention rate to reported solid-state cells with different PEO-based CSEs (Fig. 5E and table S4) (59)(60)(61)(62)(63)(64)(65)(66)(67)(68)(69)(70).…”

High‐Entropy Cubic Perovskite Oxide‐Based Solid Electrolyte in Quasi‐Solid‐State Li–S Battery

“…PEO–0.2HE–LLZO–LiTFSI shows higher cathodic and anodic peak currents compared to PEO–LiTFSI, which renders faster reaction kinetics of the polysulfides. [ 33 ] The cathodic peak current shifted to higher potential, whereas the anodic peak moved to a lower value, manifesting lesser polarization and better reversible reaction for PEO–0.2HE–LLZO–LiTFSI. Furthermore, the CV curves overlap from the second cycle onward, indicating good reversibility after the first cycle (see Figure S4, Supporting Information).…”

Proton‐Induced Defect‐Rich Vanadium Oxides as Reversible Polysulfide Conversion Sites for High‐Performance Lithium Sulfur Batteries

“…Recently, a lot of effort has been devoted to developing strategies to solve the above-mentioned issues such as the construction of active cathodes, the modification of functional separators, and optimization of the electrolyte. [9][10][11][12][13][14][15][16][17][18] As a main component, the separator can not only physically isolate cathode and anode, but also plays an indispensable role in directly suppressing the shuttle of dissolved intermediates. [19] Therefore, the development of a functional interface is desirable to improve the reaction kinetic of polysulfides and further restrict their dissolution in charge/discharge process.…”

“…Recently, a lot of effort has been devoted to developing strategies to solve the above‐mentioned issues such as the construction of active cathodes, the modification of functional separators, and optimization of the electrolyte [9–18] . As a main component, the separator can not only physically isolate cathode and anode, but also plays an indispensable role in directly suppressing the shuttle of dissolved intermediates [19] .…”