The low temperature electrochemical performances of LiFePO4/C/graphene nanofiber with 3D-bridge network structure

摘要: Abstract Three-dimensionally assembled LiFePO 4 /C/graphene nanofiber composites were successfully prepared via a suspension mixing method followed by heat-treatment at 400 °C. A faster electron transfer, lower electrochemical polarization as well higher diffusion coefficient of Li + are obtained with the assistance graphene nanofibers. The 5 wt% nanofibers modified electrode (G-5) delivers best kinetics including lowest charge transfer resistance and highest 0 °C −20 °C, respectively. Likewise, G-5 exhibits charge-discharge capability most stable cycling performance low operation temperatures compared those /C, 3 wt% 7 wt% /C (G-3 G-7) composites. shows capacity 92.8 mAh g −1 92.0% retention after 200 cycles 1C −20 °C. reasons for significant improvement performances can be ascribed to enhanced conductivity reduced agglomeration pristine particles due introduction These excellent temperature show that electrodes promising cathode candidates lithium-ion batteries applications temperatures.