High electrochemical performances of solid nano-composite star polymer electrolytes enhanced by different carbon nanomaterials

Here, two type of composite star polymer electrolytes enhanced by carbon nano-tube (CNT) or fullerene (C-60) prepared through a solution-casting technique are investigated. The as-prepared free-standing carbon nano-composite polymer electrolyte membranes exhibit excellent comprehensive performances including high thermal stability (initial thermal degradation temperatures about 383 degrees C) and good electrochemical properties. However, different carbon nanomaterials bring different influence on electrochemical performances of composite polymer electrolytes. The ionic conductivity of carbon nanotube composite polymer electrolyte (HBPS-(PMMA-b-PPEGIVIA)(30)/CNT/LiTFSI) is higher than that of fullerene composite polymer electrolyte. The highest ionic conductivity of HBPS-(PMMA-b-PPEGMA)(30)/CNT/LiTFSI electrolyte can reach 1.06 x 10(-5) S cm(-1) at 30 degrees C and lithium-ion transference number reaches 0.52. In addition, two types of carbon nano-composite star polymer electrolytes both exhibit wide electrochemical window with oxidation potential above 5.2 V, good interfacial stability and interfacial compatibility. Moreover, assembled Li/LiFePO4 cells based on HBPS-(PMMA-b-PPEGMA)(30)/CNT/LiTFSI electrolytes possess good specific capacity with the highest value of 133 mAhh g(-1), while the cells based on HBPS-(PMMA-b-PPEGMA)(30)/C-60/LiTFSI electrolytes show a great cycle stability. (C) 2017 Elsevier Ltd. All rights reserved.