Preparation of nanocomposite polymer electrolytes by incorporating poly[poly(ethylene glycol) methyl ether methacrylate]-grafted poly(amidoamine) dendrimer for high performance lithium ion batteries

Abstract

Preparation of composite polymer electrolytes (CPEs) is one of the most effective ways to improve ionic conductivity and electrochemical properties in lithium ion batteries. Dendrimers as organic fillers can improve ionic conductivity, stability, and electrochemical properties of CPEs due to their specific branched structure, low glass transition temperature, and amorphous nature. In the present work, a poly(amidoamine) (PAMAM) dendrimer RAFT agent is synthesized and utilized to prepare CPEs based on poly[poly(ethylene glycol) methyl ether methacrylate] (p(PEGMA)) matrix. The resultant CPEs are electrochemically studied by exploring electrochemical impedance spectroscopy (ESI), linear sweep voltammetry (LSV), and cycling performance during the charge/discharge cycles. The CPEs demonstrated encouraging electrochemical characteristics to utilize in lithium ion batteries such as excellent ionic conductivity in the range of 10-3 S/cm, Li-ion transference number (t+) in the range of 0.39–0.45, great electrochemical stability window (ESW) up to 5 V vs Li/Li+, and insignificant interfacial resistance. Moreover, CPEs represented good cycling performance during 100 charge/discharge cycles and favorable specific capacity of 151 mAh/g in LCO||Gr cells.