Hybrids gel electrolytes with pending polyhedral oligomeric silsesquioxane toward improving interfacial stability for lithium ion batteries

摘要

Hybrids gel electrolytes with polyhedral oligomeric silsesquioxane hung on cross-linked networks through chemical bond are designed toward improving interfacial stability for Lithium ion batteries. The corresponding hybrids gel electrolytes deliver an ionic conductivity of 2.25 x 10(-3) S cm(-1), lithium-ion transference number (t(Li+)) of 0.34 at 26 degrees C and wide electrochemical windows of 5.0 V. The Li/Li symmetric cells with this hybrid gel polymer electrolytes (HGPEs) exhibit excellent long-term stability up to 2000 hat 0.1 mA cm(-2). In particular, the LiFePO4/Li cells assembled with HGPEs exhibit good cycling performance and rate capability. The initial discharge capacity of LiFePO4/HGPEs-3/Li is 156.6 mAh g(-1) at a current rate of 0.1C at 26 degrees C. The capacity of LiFePO4/HGPEs-3/Li after 100 cycles is 131.7 mAh g(-1) with a high coulombic efficiency over 99 throughout the whole cycling process.