(1. 新疆工程學(xué)院 化學(xué)工程系，烏魯木齊 830091；
2. 新疆工程學(xué)院 基礎(chǔ)部，烏魯木齊 830091
3. 新疆工程學(xué)院 組織人事處，烏魯木齊 830091；
4. 哈爾濱慶緣電工材料有限股份公司，哈爾濱 150001)
摘 要: 采用液相共沉淀法和固相燒結(jié)法分別制備鎳鈷錳復(fù)合氫氧化物(Ni0.5Co0.2Mn0.3(OH)2)和LiNi0.5Co0.2Mn0.3O2正極材料。通過(guò)X射線衍射和電化學(xué)性能測(cè)試對(duì)所得樣品的結(jié)構(gòu)及電化學(xué)性能進(jìn)行了表征。結(jié)果表明：LiNi0.5Co0.2Mn0.3O2具有很好的α-NaFeO2層狀結(jié)構(gòu)，以20 mA/g的電流密度在2.5~4.3 V的電壓區(qū)間充放電時(shí)，最高首次放電比容量達(dá)175 mA?h/g, 首次庫(kù)倫效率在89%~90%之間。當(dāng)首次放電比容量為160~170 mA?h/g時(shí)，30循環(huán)未見(jiàn)容量衰減。鋰含量對(duì)其電化學(xué)性能影響的結(jié)果表明：鋰含量(n(Li)/n(Ni+Co+Mn))在1.03~1.09的范圍內(nèi)，隨著鋰含量的增加，放電比容量略有減小，但循環(huán)性能、中值電壓以及平臺(tái)性能都得到提高；當(dāng)鋰含量超過(guò)1.09時(shí)，循環(huán)性能、中值電壓以及平臺(tái)性能開(kāi)始降低。
關(guān)鍵字: 鋰離子電池；正極材料；LiNi0.5Co0.2Mn0.3O2；電化學(xué)性能
（1. Department of Chemical Engineering, Xinjiang Institute of Engineering, Wulumuqi 830091, China;
2. Department of Basic, Xinjiang Institute of Engineering, WuLuMuQi 830091, China;
3. Organi）
Abstract:The nickel and cobalt manganese composite hydroxide(Ni0.5Co0.2Mn0.3(OH)2) and LiNi0.5Co0.2Mn0.3O2 cathode materials were prepared by the solid state sintering synthesis and liquid phase coprecipitation. The structure and electrochemical performance were characterized by X-ray diffractometry and electrochemical properties test. The results show that the cathode material LiNi0.5Co0.2Mn0.3O2 has α-NaFeO2 structure. The highest initial discharge capacity is 175 mA?h/g at current density of 20 mA?h/g in 2.7-4.3 V (vs Li/Li+), while the coulombic efficiency is 89%-90%. When the initial discharge capacity is at the range of 160-170, the capacity does not fade after 30 cycles. When n(Li)/n(Ni+Co+Mn) are 1.03-1.09, the discharge specific capacity decreases little with molar ratio of Li to M increasing. When molar ratio of Li to M is bigger than 1.09, the cycling performance, mean voltage and discharge plateau begin to fade.
Key words: Li-ion battery; cathode material; LiNi0.5Co0.2Mn0.3O2; electrochemical properties
