(1. 湘潭大學 化學學院 環(huán)境友好化學與應用教育部重點實驗室，湘潭 411105；
2. 湖南石油化工職業(yè)技術學院，岳陽 414012)
摘 要: 采用改進的固相反應法合成了高性能的鋰離子電池正極材料LiMn2O4。首先，以廉價的MnSO4為原料，通過水解−氧化法制備納米級Mn3O4前驅(qū)體；然后，將Mn3O4和Li2CO3混合均勻，在750 ℃固相反應20 h，得到尖晶石型LiMn2O4。用X射線衍射(XRD)和掃描電鏡(SEM)對Mn3O4前驅(qū)體和LiMn2O4樣品進行表征，用充放電測試和循環(huán)伏安技術對LiMn2O4樣品進行電化學性能研究。結果表明：所制備的LiMn2O4具有完整的尖晶石型結構，且晶體粒子分布均勻。所制備的LiMn2O4材料在3.0~4.4 V之間，室溫(25 ℃)下，在0.2C倍率下首次放電比容量為130.6 mA∙h/g；在0.5C倍率下首次放電比容量為127.1 mA∙h/g，30次循環(huán)后，容量仍有109.5 mA∙h/g，且樣品具有較好的高溫性能。
關鍵字: 鋰離子電池；正極材料；尖晶石LiMn2O4；水解−氧化法；Mn3O4前驅(qū)體
YANG Shun-yi1, SHU Hong-bo1, BAI Y
（1. School of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Applications,
Ministry of Education, Xiangtan University, Xiangtan 411105, China;
2. Hunan Petrochemical Vocational Technology College, Yueyang 414012, China）
Abstract:LiMn2O4 with high-performance for the application of lithium-ion batteries was successfully synthesized by a modified solid phase reaction route. First, the precursor Mn3O4 was prepared by a hydrolyzation -oxidation method using cheap MnSO4 as Mn source. Then, the as-prepared precursor Mn3O4 and Li2CO3 were mixed homogeneously and calcined at 750 ℃ for 20 h to obtain spinel LiMn2O4. The properties of samples were characterized by XRD and SEM, charge-discharge tests and cyclic voltammetry. The results show that the as-prepared LiMn2O4 has spine structure and exhibits uniform particle size distribution. The initial discharge capacities of the as-prepared LiMn2O4 are as high as 130.9 mA∙h/g at 0.2C and 127.1 mA∙h/g at 0.5C in the voltage range of 3.0−4.4 V at 25 ℃, especially, the discharge capacity at 30th cycle still keep to be 109.5 mA∙h/g at 0.5C. Besides, the as-prepared LiMn2O4 presents good high temperature performance.
Key words: lithium ion battery; cathode material; spinel LiMn2O4; hydrolyzation-oxidation method; Mn3O4 precursor
