Morphology control and electrochemical properties of LiFePO4/C composite cathode for lithium ion batteries

• Published in: Solid state ionics 2012-10, Vol.225, p.560-563
• Main Authors: Hamamoto, K., Fukushima, M., Mamiya, M., Yoshizawa, Y., Akimoto, J., Suzuki, T., Fujishiro, Y.
• Format: Article
• Language: English
• Subjects: Carbon; Cathode; Cathodes; Charge; Density; Electrodes; Gelation–freezing method; LiFePO4; Lithium batteries; Lithium-ion batteries; Morphology; Porous; Wall thickness
• ISSN: 0167-2738; 1872-7689
• DOI: 10.1016/j.ssi.2012.01.034

We developed a novel cathode electrode system composed of ultra highly porous structured LiFePO4/carbon composite for lithium ion batteries by a gelation–freezing (GF) method. This unique technique can be used to provide various shaped components by use of specific molds, and varying the freezing temperature could control the micrometer-sized cylindrical pore size and wall thickness in the porous composite. Film shapes of carbons that originate in the gelatin were found in the porous LiFePO4/carbon composite cathodes. The porous composite cathode shows a good electrochemical performance at a low current density, despite the low carbon content. Charge/discharge capacities for the LiFePO4/carbon composites decreased with decreasing gel-freezing temperature. The template-free GF method for fabricating the porous LiFePO4/carbon composite opens up a new route to develop electrodes with controlled morphologies for applications in high power lithium batteries. ► We developed porous LiFePO4/carbon composite cathodes by a gelation-freezing method. ► Film shapes of carbons were found in the porous LiFePO4/carbon composite cathodes. ► The cathode shows a good electrochemical performance, despite the low carbon content. ► Charge capacities of the cathodes decreased with decreasing gel-freezing temperature.