Vertical-Channel Cathode Host Enables Rapid Deposition Kinetics toward High-Areal-Capacity Sodium-Chlorine Batteries

Rechargeable sodium chloride (Na-Cl₂) batteries have emerged as promising alternatives for next-generation energy storage due to their superior energy density and sodium abundance. However, their practical applications are hindered by the sluggish chlorine cathode kinetics related to the aggregation of NaCl and its difficult transformation into Cl₂. Herein, the study, for the first time from the perspective of electrode level in Na-Cl₂ batteries, proposes a free-standing carbon cathode host with customized vertical channels to facilitate the SOCl₂ transport and regulate the NaCl deposition. Accordingly, electrode kinetics are significantly enhanced, and the deposited NaCl is distributed evenly across the whole electrode, avoiding the blockage of pores in the carbon host, and facilitating its oxidation to Cl_2. With this low-polarization cathode, the Na-Cl₂ batteries can deliver a practically high areal capacity approaching 4 mAh cm^-2 and a long cycle life of over 170 cycles. This work demonstrates the significance of pore engineering in electrodes for mediating chlorine conversion kinetics in rechargeable alkali-metal-Cl₂ batteries.