In order to enhance electrochemical properties of LiFePO4 （LFP） cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The result...In order to enhance electrochemical properties of LiFePO4 （LFP） cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The results show that the spherical precursors with the sizes of 0.5-5 μm can be completely converted to LFP/C when the calcination temperature is higher than 500 ℃. The LFP/C microspheres obtained at calcination temperature of 700 ℃ are composed of numerous particles with sizes of -20 nm, and have well-developed interconnected pore structure and large specific surface area of 28.77 mE/g. The specific discharge capacities of the LFP/C obtained at 700 ℃ are 162.43, 154.35 and 144.03 mA.h/g at 0.5C, 1C and 2C, respectively. Meanwhile, the capacity retentions can reach up to 100% after 50 cycles. The improved electrochemical properties of the materials are ascribed to a small Li＋ diffusion resistance and special structure of LFP/C microspheres.展开更多
以合成的Fe PO4·2H2O为铁源和磷源,Li OH·H2O为锂源,柠檬酸﹑草酸为还原剂,采用喷雾干燥法制备球形Li Fe PO4正极材料.研究喷嘴内径﹑固含量﹑溶解时间﹑进风温度﹑蠕动泵转速对Li Fe PO4形貌的影响.X射线衍射(XRD)和扫描电镜...以合成的Fe PO4·2H2O为铁源和磷源,Li OH·H2O为锂源,柠檬酸﹑草酸为还原剂,采用喷雾干燥法制备球形Li Fe PO4正极材料.研究喷嘴内径﹑固含量﹑溶解时间﹑进风温度﹑蠕动泵转速对Li Fe PO4形貌的影响.X射线衍射(XRD)和扫描电镜(SEM)分析表明:在喷嘴内径为=0.5 mm,固含量为5%,完全溶解,进风温度160℃,蠕动泵转速750 m L/h时喷雾干燥法合成的Li Fe PO4晶型完整,颗粒均匀.展开更多
提出一种新型氧化还原液流电池:H2-Fe3+/Fe2+氧化还原液流电池。系统研究了Fe3+/Fe2+电对于未处理与热处理聚丙烯腈基石墨毡上的电化学性能及两种石墨毡组装电池充放电性能。实验结果表明:经热处理之后,石墨毡电化学反应活性面积变大,Fe...提出一种新型氧化还原液流电池:H2-Fe3+/Fe2+氧化还原液流电池。系统研究了Fe3+/Fe2+电对于未处理与热处理聚丙烯腈基石墨毡上的电化学性能及两种石墨毡组装电池充放电性能。实验结果表明:经热处理之后,石墨毡电化学反应活性面积变大,Fe3+/Fe2+电荷传递阻抗降低,从而降低了电池极化。以热处理石墨毡为电池正极,碳纸为负极组成电池,在50 m A/cm2充放电时,电压效率为87.43%,与用未处理石墨毡组装电池相比,电压效率提高11.82%,内阻降低50%。展开更多
基金Project(2013AA050901)supported by the National High-tech Research and Development Program of China
文摘In order to enhance electrochemical properties of LiFePO4 （LFP） cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The results show that the spherical precursors with the sizes of 0.5-5 μm can be completely converted to LFP/C when the calcination temperature is higher than 500 ℃. The LFP/C microspheres obtained at calcination temperature of 700 ℃ are composed of numerous particles with sizes of -20 nm, and have well-developed interconnected pore structure and large specific surface area of 28.77 mE/g. The specific discharge capacities of the LFP/C obtained at 700 ℃ are 162.43, 154.35 and 144.03 mA.h/g at 0.5C, 1C and 2C, respectively. Meanwhile, the capacity retentions can reach up to 100% after 50 cycles. The improved electrochemical properties of the materials are ascribed to a small Li＋ diffusion resistance and special structure of LFP/C microspheres.
文摘以合成的Fe PO4·2H2O为铁源和磷源,Li OH·H2O为锂源,柠檬酸﹑草酸为还原剂,采用喷雾干燥法制备球形Li Fe PO4正极材料.研究喷嘴内径﹑固含量﹑溶解时间﹑进风温度﹑蠕动泵转速对Li Fe PO4形貌的影响.X射线衍射(XRD)和扫描电镜(SEM)分析表明:在喷嘴内径为=0.5 mm,固含量为5%,完全溶解,进风温度160℃,蠕动泵转速750 m L/h时喷雾干燥法合成的Li Fe PO4晶型完整,颗粒均匀.
文摘提出一种新型氧化还原液流电池:H2-Fe3+/Fe2+氧化还原液流电池。系统研究了Fe3+/Fe2+电对于未处理与热处理聚丙烯腈基石墨毡上的电化学性能及两种石墨毡组装电池充放电性能。实验结果表明:经热处理之后,石墨毡电化学反应活性面积变大,Fe3+/Fe2+电荷传递阻抗降低,从而降低了电池极化。以热处理石墨毡为电池正极,碳纸为负极组成电池,在50 m A/cm2充放电时,电压效率为87.43%,与用未处理石墨毡组装电池相比,电压效率提高11.82%,内阻降低50%。
