How To Improve Capacity and Cycling Stability for Next Generation Li-O2 Batteries: Approach with a Solid Electrolyte and Elevated Redox Mediator Concentrations.

Because of their exceptionally high specific energy, aprotic lithium oxygen (Li-O2) batteries are considered as potential future energy stores. Their practical application is, however, still hindered by the high charging overvoltages and detrimental side reactions. Recently, the use of redox mediators dissolved in the electrolyte emerged as a promising tool to enable charging at moderate voltages.

Understanding the fundamentals of redox mediators in Li-O2 batteries: a case study on nitroxides.

The development of aprotic lithium-oxygen (Li-O2) batteries suffers from high charging overvoltages. Dissolved redox mediators, like nitroxides, providing increased energy efficiency and longer lifetime are promising tools to overcome this challenge. Since this auspicious concept is still in its infancy, the underlying chemical reactions as well as the impact of the different (electro)chemical parameters are poorly understood.

TEMPO: a mobile catalyst for rechargeable Li-O₂ batteries.

Nonaqueous Li-O2 batteries are an intensively studied future energy storage technology because of their high theoretical energy density. However, a number of barriers prevent a practical application, and one of the major challenges is the reduction of the high charge overpotential: Whereas lithium peroxide (Li2O2) is formed during discharge at around 2.7 V (vs Li(+)/Li), its electrochemical decomposition during the charge process requires potentials up to 4.