其電化學(xué)性能
( 1. 中南大學(xué) 化學(xué)化工學(xué)院, 長(zhǎng)沙 410083;
2. 湖南大學(xué) 環(huán)境科學(xué)與工程系,長(zhǎng)沙 410082;
3. 新疆大學(xué) 應(yīng)用化學(xué)研究所, 烏魯木齊 830046)
摘 要: 通過(guò)XRD、 SEM及電化學(xué)測(cè)試等手段研究了前驅(qū)體LiMn2L(Ac)2(L為檸檬酸根)的焙燒工藝條件對(duì)尖晶石LiMn2O4產(chǎn)物的結(jié)構(gòu)、形貌及電化學(xué)性能的影響。 結(jié)果表明: 提高前驅(qū)體的焙燒溫度有利于獲得晶相結(jié)構(gòu)、 微觀形貌及電化學(xué)性能均較好的LiMn2O4樣品。 在500℃焙燒2h再于750℃下保溫8~16h的分段焙燒工藝所得樣品的初始容量達(dá)到126.0mAh/g, 循環(huán)50次后容量衰減了14.5%。
關(guān)鍵字: 尖晶石LiMn2O4;低熱固相反應(yīng); 鋰離子電池; 晶胞參數(shù)
LiMn2L(Ac)2 and its electrochemical properties
JIA Dian-zeng3, HUANG Ke-long1
( 1. College of Chemistry and Chemical Engineering,
Central South University,Changsha 410083, China;
2. Department of Environmental Science and Engineering,
Hunan University,Changsha 410082, China;
3. Institute of Applied Chemistry, Xinjiang University, Wulumuqi 830046, China)
Abstract: The effects of thermo-decomposing process of LiMn2L(Ac)2 on the structures, micromorphologies and electrochemical properties of the LiMn2O4 product were studied by XRD, SEM and charge/discharge tests. The results suggest that the LiMn2O4 samples, which were obtained at the higher sintering temperature, exhibit the more perfect crystal structure, more regular micromorphology and better electrochemical properties. When the sintering temperature is higher than 750℃, the subsect-heating technology should be used to avoid the Li2MnO3 impurities. The LiMn2O4 sample prepared by sintering the precursor first at 500℃ for 2h and then at 750℃ for 8-16h has the first capacity of 126.0mAh/g, and the capacity fading 14.5% after 50 cycles.
Key words: spinel LiMn2O4; low-heating solid-state reaction; Li-ion batteries; lattice parameter


