Optimization of electrochemical performance of NMC cathode via adjacent synthesis and test protocols

Abstract

LiNixMnyCo1-x-yO2 (so-called NMC) has demonstrated the most effective combination of nickel, manganese, and cobalt for the cathode materials to yield better performance in terms of specific energy and power density, life span, costs and safety at Li-ion Batteries-LiB. Nickel is responsible for high energy density and good storage capacity of LiBs, but suffers from low thermal stability and insufficient cycle life. Considering these deficiencies, the NMC compositions are designed to include Manganese which acts not only as a stabilizer, but also prevents Nickel oxidation and thus, reduces the risk of capacity fading. Moreover, a new generation of cathode microparticles have been emerged aiming in a clever integration of Manganese in NMC morphologies by their core/shell structured designed synthesis. This special morphology provides surface stabilization of Ni-rich NMC by Manganese rich shell, to keep the energy storage capabilities at a higher level and thus, preventing the early cathode degradation. The strong dependence of the NMC cathode’s functional properties on the relative ratios of the involved transition metals as well as the insufficient understanding of the synergistic effect of core and shell during the electrochemical tests, forced the researches to explore new synthesis approaches to enhance the overall performance of cathodes with this new structural design.