ISSP UL Scientific workshop

Characterisation and optimization of LiFePO₄ lithium ion battery cathode material Karīna Bikova (LU CF), Gunārs Bajars (LU ISSP) In recent years, LiFePO₄ has been considered to be one of the most promising cathode materials for lithium-ion batteries. LiFePO₄ material has relatively low cost and high safety, it is considered as a promising cathode for electric and hybrid vehicle applications. LiFePO₄ has good thermal stability, high theoretical capacity (170 mAh/g), excellent cyclability and potentially low production costs. One of the challenges related with this material is associated with increasing the rate capability, which is related to its low electron conductivity and slow lithium ion diffusion through the LiFePO₄-FePO₄ interface. There are several ways to solve this problem, for example, improving the electrical conductivity by coating particles with a layer of highly electron conductive materials or reduction of the particle size by changing the synthesis conditions. Most often used electron-conductive additives in lithium ion batteries are carbon coating or simply carbon powder mixed with LiFePO₄. Recently a lot of attention has been devoted to graphene, because it is one of the best electron conductor available at room temperature, however, so far graphene as LiFePO₄ additive has been studied relatively little. Preparation and characterization of TiO2 and Al2O3 thin films produced by electrophoretic deposition Ineta Liepina (LU CF) Due to its photocatalytic properties, titanium dioxide has application in environmental and energy-related fields. In the first case TiO2 is used to oxidize organic pollutants and bacteria into less hazardous substances in water or air, second field uses sunlight to generate photocurrent or hydrogen from photoelectrolysis. Important factor for increasing TiO2 photoactive performance is nanostructuring - reducing the particle size, expanding specific surface area and pore volume, and preferable crystalline phase modification. Generally accepted way of extending the spectral response of TiO2 to the visible light is doping with transition metal ions. Alumina-nickel composite coating production has been of increased interest, due to its mechanical, optical and electrical properties. Al2O3-Ni has the potential use in mass production as solar absorber, oxide fuel cell electrode and electrochemical capacitor.