(1. 四川大學 化學工程學院，成都 610065；2. 四川大學 材料科學與工程學院，成都 610065)
摘 要: 以有機−水為混合溶劑，采用溶膠−凝膠法制備鋰離子電池正極材料Li3V2(PO4)3/C。通過X射線衍射 (XRD)、掃描電鏡(SEM)、恒流充放電以及循環(huán)伏安(CV)測試等方法，研究產(chǎn)物的結(jié)構形貌及電化學性能。結(jié)果表明：溶劑對材料的晶型結(jié)構沒有影響，對顆粒的形貌影響較大；以1, 2-丙二醇−水為溶劑的樣品呈薄片狀和針狀；在3.0～4.5 V電壓范圍內(nèi)，Li3V2(PO4)3/C的0.1C首次放電比容量為132.89 mA∙h/g，10C首次放電比容量達125.42 mA∙h/g，循環(huán)700周后容量保持率為95.79%，具有良好的倍率性能與循環(huán)性能；而在3.0～4.8 V電壓范圍內(nèi)倍率性能較差。
關鍵字: Li3V2(PO4)3；鋰離子電池；正極材料；溶膠−凝膠法；有機−水混合溶劑
different organic-water mixed solvents
（1. College of Chemical Engineering, Sichuan University, Chengdu 610065, China;
2. College of Materials Science and Engineering, Sichuan University, Chengdu 610065, China）
Abstract:The cathode material Li3V2(PO4)3/C was synthesized by sol-gel method using organic and water as mixed solvents. The structure, morphology and electrochemical performance of the synthesized cathode materials Li3V2(PO4)3/C were studied by X-ray diffractometry (XRD), scanning electron microscopy (SEM), charge-discharge tests and cycle voltammetry (CV). The results show that different solvents have no effect on the crystal structure of the samples, but have great impact on the morphology of the particles. The sample prepared by using 1, 2-propylene glycol-water as the mixed solvent has a flake-like and needle-like shape, it exhibits an initial discharge capacity of 132.89 mA∙h/g at 0.1C rate in the voltage range of 3.0−4.5 V; the initial discharge capacity is as high as 125.42 mA∙h/g when discharging at 10C, which keeps a capacity retention of 95.79% after the 700th cycle, indicating good rate and cycling performance; however, it exhibits a bad rate performance in the voltage range of 3.0−4.8 V.
Key words: Li3V2(PO4)3; lithium ion batteries; cathode material; sol-gel method; organic-water mixed solvents
