应用高温气相扩散沉积法由单质硫制备硫膨胀石墨.该硫膨胀石墨正极可降低反应界面电荷传递阻抗,提高扩散阻抗抑制单质硫或多硫化物在充放电过程的穿梭.其首次放电容量达到972 mAh.g-1,容量保持率为78%,循环效率在80%以上.
The exfoliated graphite containing sulfur cathode material was prepared by the high temperature sulfur gas diffusion adsorption method.This cathode material could obtain an initial discharge specific capacity 972 mAh·g-1,capacity retention ratio 78% and cycling efficiency above 80%,respectively.The exfoliated graphite containing sulfur cathode could decrease the reaction interphase charge transfer impedance,and restrain the sulfur or polysulfide shuttle phenomenon during the charge-discharge process through improving the diffusion impedance.
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