High-Energy-Density Lithium-Sulfur Batteries Based on Blade-Cast Pure Sulfur Electrodes

A facile pure sulfur electrode strategy is demonstrated to increase the areal loading of blade-cast sulfur electrodes and improve the electrochemical performances of thick sulfur electrodes with consideration for scale-up in practical, commercial applications. Benefiting from the unique pure sulfur electrode and an upper current collector design, the pure sulfur electrode displays low polarization, high sulfur utilization, and promising cycling stability even with an ultrahigh sulfur loading. A high areal capacity of 19.2 mAh cm(-2) has been achieved, which is the highest areal capacity for the reported blade-cast sulfur electrodes and 4 times higher than that of available lithium-ion battery electrodes. Furthermore, we demonstrate that the use of large-sized sulfur particles only slightly decreases the rate of conversion from S-8 to S-4(2-) during the initial discharge and has negligible impact on subsequent electrochemical performance.