(中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083)
摘 要: 以碳酸氫銨為沉淀劑采用共沉淀法合成球形Co0.9Ni0.05Mn0.05CO3前驅(qū)體，以碳酸鹽前驅(qū)體和Li2CO3為原料，在空氣中通過固相反應(yīng)制備出LiCo0.9Ni0.05Mn0.05O2正極材料，研究燒結(jié)溫度對產(chǎn)物結(jié)構(gòu)及電化學(xué)性能的影響。采用掃描電鏡(SEM)、X射線衍射(XRD)和光電子能譜(XRS)分別表征樣品的形貌、結(jié)構(gòu)和元素價態(tài)。結(jié)果表明：不同燒結(jié)溫度下合成產(chǎn)物的性能差別很大，較適合的合成溫度為900 ℃；在3.0~4.5 V電壓范圍內(nèi)，LiCo0.9Ni0.05Mn0.05O2顯示出較好的倍率性能；在25 ℃測試條件下，材料在0.2C、0.5C、1C、5C和10C時的放電比容量分別為181.6、178.3、173.9、167.8和157.1 mA？h/g。
關(guān)鍵字: 鋰離子電池；正極材料；碳酸氫銨；共沉淀
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:The spherical precursor of metal carbonate, Co0.9Ni0.05Mn0.05CO3, was prepared by co-precipitation method using NH4HCO3 as precipitating agent. LiCo0.9Ni0.05Mn0.05O2 was prepared by solid-state reaction method in air using Co0.9Ni0.05Mn0.05CO3 and Li2CO3 as starting materials. The effects of sintering temperature on the structure and electrochemical properties of the product were studied. The morphology and structure of LiCo0.9Ni0.05Mn0.05O2 were characterized by SEM and XRD, respectively. The valence state of transition metal was determined by XPS. The results show that sintering temperature has a critical role in the performance of the product and the suitable sintering temperature is 900 ℃. LiCo0.9Ni0.05Mn0.05O2 exhibits good cycle performance and high rate capability within the voltage range of 3.0-4.5 V. At 25 ℃, the initial discharge capacity are 181.6, 178.3, 173.9, 167.8 and 157.1 mA？h/g at 0.2C, 0.5C, 1C, 5C and 10C, respectively.
Key words: lithium-ion battery; cathode material; ammonium bicarbonate; co-precipitation
