Enhanced Electrochemical Performance of PEO-Based Composite Polymer Electrolyte with Single-Ion Conducting Polymer Grafted SiO2 Nanoparticles

Xuan Liu; Wanning Mao; Jie Gong; Haiyu Liu; Yanming Shao; Liyu Sun; Haihua Wang; Chao Wang

doi:10.3390/polym15020394

Enhanced Electrochemical Performance of PEO-Based Composite Polymer Electrolyte with Single-Ion Conducting Polymer Grafted SiO₂ Nanoparticles

Polymers (Basel). 2023 Jan 11;15(2):394. doi: 10.3390/polym15020394.

Authors

Xuan Liu^{1

2}, Wanning Mao^{1

2}, Jie Gong^{1

2}, Haiyu Liu^{1

2}, Yanming Shao^{1

2}, Liyu Sun^{1

2}, Haihua Wang^{1

2}, Chao Wang^{1

3}

Affiliations

¹ Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry, Ministry of Education, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
² Shaanxi Key Laboratory of Chemical Additives for Industry, Shaanxi University of Science and Technology, Xi'an 710021, China.
³ Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry & Technology, The Youth Innovation Team of Shaanxi Universities, Shaanxi University of Science and Technology, Xi'an 710021, China.

Abstract

In order to enhance the electrochemical performance and mechanical properties of poly(ethylene oxide) (PEO)-based solid polymer electrolytes, composite solid electrolytes (CSE) composed of single-ion conducting polymer-modified SiO₂, PEO and lithium salt were prepared and used in lithium-ion batteries in this work. The pyridyl disulfide terminated polymer (py-ss-PLiSSPSI) is synthesized through RAFT polymerization, then grafted onto SiO₂ via thiol-disulfide exchange reaction between SiO₂-SH and py-ss-PLiSSPSI. The chemical structure, surface morphology and elemental distribution of the as-prepared polymer and the PLiSSPSI-g-SiO₂ nanoparticles have been investigated. Moreover, CSEs containing 2, 6, and 10 wt% PLiSSPSI-g-SiO₂ nanoparticles (PLi-g-SiCSEs) are fabricated and characterized. The compatibility of the PLiSSPSI-g-SiO₂ nanoparticles and the PEO can be effectively improved owing to the excellent dispersibility of the functionalized nanoparticles in the polymer matrix, which promotes the comprehensive performances of PLi-g-SiCSEs. The PLi-g-SiCSE-6 exhibits the highest ionic conductivity (0.22 mS·cm^-1) at 60 °C, a large t_Li+ of 0.77, a wider electrochemical window of 5.6 V and a rather good lithium plating/stripping performance at 60 °C, as well as superior mechanical properties. Hence, the CSEs containing single-ion conducting polymer modified nanoparticles are promising candidates for all-solid-state lithium-ion batteries.

Keywords: RAFT polymerization; SiO2 modification; all-solid-state battery; composite solid electrolyte; single-ion conducting polymer grafting.

Abstract

Grants and funding