Fig. 3: Quantitative analysis of species transport inside visualized electrodes under different Li+ ion concentrations.
a The cross-section of the C-AAO electrode with a channel diameter of 390 nm before discharge. The SEM images of Li2O2 distribution at the oxygen side, middle part, and separator side and the statistical analysis of particle size at the concentration of (b) 0.5 M and (c) 2 M. The scale bars in (b, c) are 200 nm. d The summary of average Li2O2 diameters with 0.5–2 M electrolytes. The error bars in (d) represent the standard deviation derived from numerous particle diameter measurements. The simulated distribution of oxygen concentration at (e1) 60%, (e2) 80%, and (e3) 100% DODs in the 0.5 M electrolyte and at (f1) 60% and (f2) 100% DODs in the 2 M electrolyte. g The average oxygen concentration and the corresponding voltage-capacity curves. The simulated distribution of Li2O2 volume fraction at (h1) 60%, (h2) 90%, and (h3) 100% DODs in the 0.5 M electrolyte and at (i1) 80% and (i2) 100% DODs in the 2 M electrolyte. The positions of the Li2O2 maximum volume fractions are marked by white dots. j Migration of the Li2O2 maximum volume fraction site in the electrode depth direction as the discharge proceeds. The simulated distribution of local current discharge along the electrode surface in (k) 0.5 M and (l) 2 M electrolytes, with Lpos = 0 representing the oxygen face and Lpos = 1 representing the separator face. m Scheme of mass transport characteristics in 0.5 and 2 M electrolytes.
