Composite solid electrolyte comprising poly(propylene carbonate) and Li1.5Al0.5Ge1.5(PO4)3 for long-life all-solid-state Li-ion batteries. (1st October 2021)

• Record Type: Journal Article
• Authors: Sung, Bong-Joon; Didwal, Pravin N.; Verma, Rakesh; Nguyen, An-Giang; Chang, Duck Rye; Park, Chan-Jin
• Is Part Of: Electrochimica acta. Volume 392(2021)
• Publication Date: 2021-10-01
• Subjects: Poly(propylene) carbonate -- Li1.5Al0.5Ge1.5(PO4)3 inorganic filler -- Composite solid polymer electrolyte -- Long cyclability -- All-solid-state Li-ion battery; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2021.139007
• Languages: English
• ISSNs: 0013-4686

Abstract

Research Highlights: Solid polymer electrolyte (CSPE) comprised poly(propylene carbonate) and Li1.5 Al0.5 Ge1.5 (PO4 )3 . CSPE exhibited a high ionic conductivity of ∼5.63 × 10 −4 S cm −1 at 60°C. The Li/CSPE/Li cell displayed a superior stability over 1000 h with minimal over potential. The Li/CSPE/LFP delivered a specific discharge capacity of 151 mAh g −1 at 0.1 C. The Li/CSPE/LFP exhibited an excellent cyclability over 1000 cycles at 1 C. Abstract: Solid electrolytes are a potential candidate for mitigating the safety issues associated with organic liquid-electrolyte-based conventional Lithium-Ion Batteries (LIBs). The film-forming ability, cost-effective fabrication, and superior interfacial contact of solid polymer electrolytes make them particularly appealing for application in all-solid-state LIBs (ASSLIBs). However, their practical applications are limited owing to their low lithium-ion conductivity and inadequate mechanical strength. In this study, we fabricated a highly flexible, soft, self-standing, and stable composite solid polymer electrolyte (CSPE) using poly(propylene carbonate) (PPC) as the main matrix and Na-superionic-conductor-type Li1.5 Al0.5 Ge1.5 (PO4 )3 (LAGP) as the active inorganic filler. The fabricated CSPE exhibited an attractive ionic conductivity of ∼0.56 mS∙cm −1, a wide electrochemical potential stability of ∼5 V vs. Li/Li +, a high lithium-ion transference number of ∼0.77, outstanding stability up to 1000 cycles of lithium plating/stripping, and better compatibility with lithium metal. In addition to these outstanding properties, the Li/CSPE/LiFePO4 (Li/CSPE/LFP) cell exhibited an impressive discharge capacity of 151 mAh∙g −1 at 0.1 C. Furthermore, at a rate of 1 C, the Li/CSPE/LFP cell delivered an initial discharge capacity of 96 mAh∙g −1, with a capacity retention of 63% over 1000 cycles. The interaction of lithium ions with the PPC was confirmed based on solid-state MAS NMR and XPS. The enhanced electrochemical performance of the CSPE is ascribed to the interaction of the LAGP filler with the PPC matrix, which forms a good polymer-inorganic interface, enabling the rapid lithium-ion transport. The proposed LAGP-reinforced CSPE presents new opportunities for the fabrication and engineering of ASSLIBs. Graphical Abstract: A solid polymer electrolyte composed of poly(propylene carbonate) and LAGP ceramic filler opens avenue for easy Li ion transportation and exhibited outstanding stability with Li anode as well as LFP cathode. Image, graphical abstract