Improved battery performance contributed by the optimized phase ratio of β and α of PVDF

Inorganic salts (LiCl) were induced to improve the ratio of beta and alpha of PVDF by the solution method. The vibrational spectra of PVDF polymorphic polymers were obtained by Fourier transform infrared spectroscopy (FTIR), and the results showed that the ratio of beta and alpha of pristine PVDF was elevated from 43.66% to 53.27%. A small amount of LiCl grains was detected to be decorated on the surface of LiCl-involved electrodes by the SEM and EDS tests. The rate capability of the modified samples was evaluated when charge-discharged at 5C. The capacity of the 1/10LiCl@PVDF samples remained at a high level of 71.64% when charge-discharged at 5C, which was much higher than the value of 54.66% for pristine samples. The results of the CV and EIS tests revealed that the electrochemical polarization increasing rate and charge transfer resistance of the 1/10LiCl@PVDF samples were smaller than those of the pristine PVDF samples.