摘要
高电容量的电极材料对于需要高能量密度锂离子的携带式电子设备相当重要。由于需求不同,电极的制作方式与材料的选用相当繁杂。本研究是将回收硅粉和沥青粉末混合,再与炭毡复合成炭纸,经250℃稳定化与1 000℃炭化后,制备出兼具电极与集流板功能炭复合纸。经循环充放电测试后,添加不同比例硅粉(2.5 wt%, 5 wt%, 10 wt%)的负极,相较于炭复合电极放电电容量分别提升了94%、129%和41%。
High-capacity electrode materials are critical for portable electronic equipment that requires a high-energy density from lithium ion batteries(LIBs). Many different materials and fabrication methods for such electrodes have been developed for this purpose. Carbon paper coated with recycled silicon powder(CP-RSP) was prepared by coating silicon and pitch powder on the carbon paper, followed by stabilization at 250 ℃ in air and carbonization at 1 000 ℃ in N_2. The CP-RSP acted as both the current-collector and the active material for the anodes of LIBs. Electrodes with 2.5, 5, and 10 wt.% silicon exhibited capacity increases of 94, 129 and 41%, respectively, compared with the silicon-free electrode. The electrode for the CP-RSP with 5 wt.% silicon exhibited an optimal balance between discharge capacity and stability in long-cycle tests under various charging rates.
引文
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