Due to the high availability of components and the consequent low price, aluminum-organic batteries are a competitive candidate in the field of electrochemical energy storage. Aluminum has both high gravimetric and volumetric theoretical capacity. The bottleneck of current aluminum batteries is the choice of electrolytes and positive electrode materials. Among electrolytes, ionic liquids based on aluminum chloride and 1-ethyl-3-methylimidazolium chloride have so far shown the best electrochemical performance, while organic materials were demonstrated as the best electrode materials. In this master's thesis we studied the electrochemical mechanism of Al-phenanthrenquinone battery system. Two-electron reduction of phenanthrenequinone was confirmed by ex situ and operando IR spectroscopic measurements and ex situ XPS, SEM-EDS and MAS NMR measurements were used to conclude that [AlCl]2+ species from the electrolyte are mostly involved in the electrochemical mechanism of this battery. A good understanding of the operation is essential, as the amount of chloride in the coordinating cation significantly affects the anode capacity and the number of electrons received affects the cathode capacity.
|
