Activation of Passive Nanofillers in Composite Polymer Electrolyte for Higher Performance Lithium‐Ion Batteries

Abstract

Poor ionic conductivity in gel or solid electrolytes hinders the electrochemical performance and hence applications of solid‐state lithium‐ion batteries. In this work, a simple and efficient approach to increase the ionic conductivity of gel electrolytes is reported. Composite gel polymer electrolyte (CGPE) films, consisting of poly(vinylidene fluoride‐hexafluoropropylene) as the host polymer and the trilayer polypropylene membrane as the mechanical support, are prepared using charge‐modified acidic TiO2 and basic SiO2 nanoparticles as ionic conductors. Ionic conductivities of 1.56, 1, and 1 × 10−2 mS cm−1 for acidic CGPE, basic CGPE, and CGPE without nanofillers are achieved, respectively. The Li‐graphite cells employing the modified nanofillers incorporated CGPE show an enhanced electrochemical performance with the first cycle specific capacity of 412/408.5 mAh g−1 for the cell with acidic CGPE and 349/347.18 mAh g−1 with basic CGPE at the C/20 rate. After five cycles, each of C/8, C/4, C/2, and 1C, the acidic CGPE demonstrates a capacity retention of 78% compared to that of the basic one with 70%. This modification method has been demonstrated as a simple, facile, and scalable technique to improve electrolyte performance for solid‐state lithium‐ion batteries.

Recent advances in gel polymer electrolyte for high-performance lithium batteries

“…The Mg(OH) 2 ceramic particles were also incorporated into PVDF-HFP-based GPE, which enhanced flame-retardant properties and ionic conductivities of electrolyte [30] . To reduce the aggregation of fillers, a charge-modified acidic TiO 2 and basic SiO 2 nanoparticles were introduced into composite GPE (CGPE) consisting of PVDF-HFP as the host polymer and the tri-layer polypropylene membrane as the mechanical support [31] . A maximum ionic conductivities of 1.56 × 10 −3 S cm −1 was achieved in acidic CGPE.…”

Flame Retardant and Stable Li1.5Al0.5Ge1.5(PO4)3-Supported Ionic Liquid Gel Polymer Electrolytes for High Safety Rechargeable Solid-State Lithium Metal Batteries

“…Clean and convenient lithium ion batteries (LIBs) have been widely used in most aspects of people’s lives to address the energy shortages, environmental pollution, and other issues gradually highlighted. − High security is at the forefront in their many performance requirements except high energy density and good cycle performance for LIBs. − At present, the carbonate-based volatile and flammable liquid electrolytes suffer from drawbacks such as leakage and flammability, causing explosion and other safety risks. − Solid electrolytes are well-known as high safety and prompt the development as a hot spot. ,, However, the major challenge to realize practical application of the all-solid-state battery is the poor contact/adhesion at the solid electrolyte-electrode. − The GPEs are generally prepared by swelling the liquid electrolyte in the polymer matrix, , which can take into account both important merits of the above two types of electrolytes.…”

Preparation and performance study of a PVDF–LATP ceramic composite polymer electrolyte membrane for solid-state batteries

“…[1][2][3][4] Nevertheless, the metal dendrites formed in liquid electrolyte systems can penetrate the polymer separators, which can lead to serious and sporadic safety issues in long-term cycling applications. [5][6][7] All-solid-state Li-ion batteries, where the ammable liquid electrolyte is replaced by solid state electrolytes, offer the possibility to solve the safety issues of traditional Li-ion batteries arising from the leakage of ammable organic liquid electrolytes, and in some cases a large electrochemical stability window compared to conventional organic electrolytes. [8][9][10] In past studies, many kinds of crystalline lithium solid electrolyte have been reported and widely applied in solid-state batteries, such as the garnet structure Li 7 La 3 Zr 2 O 12 (LLZO), 11 the perovskite structure Li 0.5 La 0.5 TiO 3 (LLTO), 12 the LISICON structure Li 14 Zn(GeO 4 ) 4 (LZGO), 13 the NASICON structure Li 1.5 -Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP), 14,15 Li 1.4 Al 0.4 Ti 1.6 (PO 4 ) 3 (LATP), 16,17 and so on.…”