Our experiments confirm that increasing the OH -concentrations from 1.0 to 1.5 and 2.0 M decreases the fade rate from 4.3%/day to 1.34 and 0.38%/day, respectively. Under 0-85% SOC restriction conditions, the fade rate at those OH -concentrations reach 0.7, 0.18, and 0.09%/day, respectively. Clearly, combining 0-85% SOC cycling with a higher OH -concentrations greatly decreases the fade rate. Additionally, with the effect of the regeneration technique, the fade rate is observed to be around 0.05 and 0.02%/day, in 1.0 and 1.5 M OH -, respectively. The fade rate in 2.0 M OH -is also 0.02%/day, which is not lower than that in 1.5 M OH -because of a lower recovery efficiency. The recovery efficiency drops from 94% to 87% and to 74% as the OH -concentration increases from 1.0 to 1.5 and 2.0 M.