(1. 中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083；
2. 湖南工程學(xué)院 化學(xué)化工學(xué)院，湘潭 411104)
摘 要: 以控制結(jié)晶法合成的球形Ni0.8Co0.15Al0.05(OH)2.05為前驅(qū)體，采用加壓氧化法制備鋰離子電池正極材料LiNi0.8Co0.15Al0.05O2。利用X射線衍射(XRD)、掃描電鏡(SEM)和恒電流充放電測(cè)試等方法對(duì)該材料的結(jié)構(gòu)、形貌及電化學(xué)性能進(jìn)行表征。考察氫氧化鋰與前驅(qū)體物質(zhì)的量之比(鋰配比)、在煅燒過程中的壓力、溫度和時(shí)間等因素對(duì)LiNi0.8Co0.15Al0.05O2材料結(jié)構(gòu)及性能的影響。結(jié)果表明：鋰配比為1.02時(shí)，在0.4 MPa氧氣壓力下，于700 ℃煅燒10 h制備的材料具有最完善的結(jié)構(gòu)和最好的電化學(xué)性能；在2.8~4.3 V電壓范圍內(nèi)，以0.2 C進(jìn)行充放電，首次放電比容量達(dá)到190.1 mA?h/g，50次循環(huán)后容量保持率為90.2%，同時(shí)顯示出良好的倍率性能和高溫性能。
關(guān)鍵字: 鋰離子電池；正極材料；LiNi0.8Co0.15Al0.05O2；加壓氧化
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China;
2. School of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411）
Abstract:The cathode materials LiNi0.8Co0.15Al0.05O2 were synthesized under elevated oxygen pressure from spheric Ni0.8Co0.15Al0.05(OH)2.05 prepared by controlled crystallization method. The materials were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and galvanostatic charge-discharge tests. The effects of molar ratio of Li to Ni+Co+Al, oxygen pressure, temperature and time during calcining on the material structure and electrochemical properties of LiNi0.8Co0.15Al0.05O2 were examined. The results show that, under the conditions of the molar ratio of Li to Ni+Co+Al of 1.02, oxygen pressure of 0.4 MPa, temperature of 700 ℃ and time of 10 h, the obtained material exhibits the most ordered structure and the best electrochemical performance. The initial discharge specific capacity of the material is 190.1 mA·h/g at 0.2 C in the voltage range of 2.8?4.3 V, and after 50 cycles, 90.2% of the initial discharge capacity of the material is maintained. Besides, the material also exhibits excellent rate capability and high-temperature performance.
Key words: lithium ion battery; cathode material; LiNi0.8Co0.15Al0.05O2; oxidation under elevated pressure
