Electronic and structural properties of Li_1tn(_1tn1_1tn-_1tnx_1tn)FePO_1tn4 (X=0, 0.5, 1) [Elektronische Ressource] / vorgelegt von Michael Kiarie Kinyanjui

Electronic and Structural PropertiesofLi FePO (X = 0 , 0.5 ,1)4(1-x)Zur Erlangung des Doktorgrades Dr. rer. nat.der Fakultät für Naturwissenschaftender Universität Ulmvorgelegt vonMichael Kiarie KinyanjuiausKaruri, KenyaUlm 2010Amtierender Dekan: Prof. Dr. Axel Groß1. Gutachterin: Prof. Dr. Ute Kaiser2. Gutachter: Prof. Dr. Werner TillmetzTag der Promotion:30.5.2010The work described in this thesis was performed at the Materials science groupof Electron Microscopy, University of Ulm and Center for Solar Energy and Hy-drogen Research, Ulm. It is part of the research program ReaLiBatt and wasmade possible by financial support from the (German Federal Ministry of Edu-cation and Research) (Bundes Ministerium für Forschung and Bildung, BMBF)and Germanh Foundation ( Deutsche Forschungsgemeinschaft, DFG)andindustrial partnersDedicationThis thesis is dedicated my parents who taught me tobe ambitious and never to to give up.()M. K. Kinyanjui ivAbstractLithium ion batteries are widely used for energy storage in many electronicdevices. It is well known that the ability of a lithium ion battery to store energyis dependent on the properties of the materials which are used to construct thebattery (see M.Winter and R.J. Brodd, Chem. Rev. 104, 4245 (2004)). Thesematerials include those used as the anode, cathode,and electrolyte. Lithium ironphosphate (LiFePO ) is currently applied as a cathode material for lithium ion4batteries.