Battery and Fuel Cell Technology

Lithium ion batteries are widely used in many portable applications and are the most promising energy storage systems for future mobility and stationary applications. Worldwide, extensive research efforts focus on the development of high performance, low cost and more sustainable materials for advanced lithium ion batteries. In this presentation, we describe various strategies to increase the energy density of lithium ion batteries by combining high voltage and high capacity cathode materials as nickel rich layered oxides or high voltage spinel type materials with silicon/carbon composites. An alternative approach is the development of cobalt free cathode materials. Co-free, Li-rich Li1+xNi0.5Mn1.5O4 (0<x<1) compounds are very promising candidates for high energy applications. The lithium‐nickel‐manganese oxide compounds can be tailored with respect to composition in order to reach high capacities up to 250 mAh g-1 with long cycling life. An adapted electrode manufacturing process including a deep understanding of the interactions between powder properties, process parameters and electrochemical performance is essential to get maximum cell performance. In addition, lithium plating can occur during charging, which is a severe ageing mechanism and a potential safety risk. Adapted cathode materials with excess of lithium can be used to compensate irreversible losses of silicon based anode materials and to prolong life time in full cells.