(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 以納米硅粉(Si)、鱗片石墨(FG)和檸檬酸為原料，通過(guò)液相固化-高溫?zé)峤夥ㄖ苽涔杼?Si/C)復(fù)合材料，采用XRD和SEM表征復(fù)合材料的結(jié)構(gòu)和形貌；采用不同的黏結(jié)劑-聚四氟乙烯(PVDF)和褐藻酸鹽(SA)分別對(duì)材料的電化學(xué)性能進(jìn)行表征。結(jié)果表明：采用PVDF和SA作為粘結(jié)劑時(shí)，材料首次可逆比容量分別為528.7和538.5 mA?h/g，首次庫(kù)侖效率分別為69.57%和63.38%，但是采用SA作為粘結(jié)劑時(shí)材料呈現(xiàn)出良好的循環(huán)性能，20次循環(huán)后容量保持在90%以上。
關(guān)鍵字: 鋰離子電池；負(fù)極材料；Si/C復(fù)合材料；電化學(xué)性能
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The Si/C composite was prepared by pyrolyzing the citric acid mixed with nano-silicon and flake graphite powders. X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of the composite. The electrochemical performance of the composites was investigated by using two different binders polytetrafluoroethene (PVDF) and sodium alginate (SA), respectively. The results shows the initial capacities of the composite using different binders are 528.7 and 538.5 mA?h/g, respectively, and the initial efficiencies are 69.57% and 63.38%, respectively. However, the composite exhibits a better cycling performance when using the SA binder, and the capacity retention is more than 90% after 20 cycles.
Key words: Li-ion batteries; anode; Si/C composites; electrochemical performance
