Nano-silica-decorated Poly(m-Phenylene Isophthalamide) Separator with Enhanced Mechanical and Electrolyte Wetting Properties for Lithium-Ion Batteries

Jianjie Wang,Wei Wu,Fusheng Pan,Jun Guo,Zan Chen,Biao Yuan,Cuijia Duan,Yanlei Su,Lina Qiao

doi:10.1007/s12209-020-00256-6

Abstract

Heat-resistant poly(m-phenylene isophthalamide) (PMIA) has attracted considerable attention as a novel separator for application in lithium-ion batteries (LIBs); however, its mechanical strength and electrolyte wettability are not ideal. Herein, a nano-silica-decorated poly(m-phenylene isophthalamide) (PMIA@SiO2) separator was fabricated with SiO2 nanoparticles uniformly attached to the pores and pore walls of the PMIA separator. The as-prepared PMIA@SiO2 separator has good mechanical strength (a 16% improvement compared with pristine PMIA) and wettability toward the electrolyte (the contact angle decreases from 34.0° to 23.1°). The PMIA@SiO2 separator also had a high ionic conductivity (0.75 mS/cm) and low interfacial electric resistance (75 Ω). The assembled LiCoO2/PMIA@SiO2-liquid electrolyte/Li cell displays good cycle performance with a capacity retention of 88.1% after 50 cycles. Furthermore, the cycling performance and rate capacity rarely changed after high-temperature treatment. Therefore, the nano-silica-decorated PMIA separator is a potential candidate for application in LIBs with high safety.

Highlights

Lithium-ion batteries (LIBs) are widely used in portable electronic devices and electric vehicles [1, 2]
After the decoration of S iO2 nanoparticles on the separator, the SiO2 nanoparticles agglomerated without Tween-80 as the auxiliary, as shown in Fig. 2c, d and Fig. S7
A nano-silica-decorated PMIA separator with good mechanical strength and wettability toward the electrolyte was successfully prepared

Summary

Introduction

Lithium-ion batteries (LIBs) are widely used in portable electronic devices and electric vehicles [1, 2]. The mechanical strength and wettability of the separator toward electrolytes are essential factors in LIBs, which can influence the internal resistance and ionic conductivity, affecting the safety and cycle performance of the battery.

Results

Conclusion