Effect of Electrolyte Conductivity on the Discharge Behavior of Lithium–Oxygen Batteries: Results from Modeling and Experiments

A simplified model of lithium–oxygen battery (LOB) discharging is described. Presenting the positive electrode as a monoporous medium characterized by two parameters (porosity and pore radius) allows the study of lithium peroxide formation to be limited to a single pore. A unique aspect of this model is the LOB discharge curve being considered in a broad range of conductivities for a lithium-containing electrolyte. The current density and electrolyte conductivity are considered the core model parameters of LOB discharging. Experimental dependences are investigated for LOB discharge capacity and electrolyte conductivity on the concentration of lithium in an aprotic medium. Based on the results from modeling and experimental data, it is suggested which limiting factors might be responsible for extremely low allowable current densities during LOB discharging.