Protonated Pyridinic Nitrogen Enhances Chloride Conversion for Ultrastable Li/Na‐Cl <sub>2</sub> Batteries
Xinru Wei, Deyuan Kong, Wenting Feng, Fengliang Cao, Chenyu Ma, Jianhang Yang, Junwei Han, Lin Wang, Guanzhong Ma, Han Wang, Yiming Sun, Zihui Liu, Ling Wei, Linjie Zhi
Abstract
Abstract Rechargeable Li/Na‐Cl 2 batteries, which utilize Cl 2 and Li/NaCl redox conversions, have garnered significant attention owing to their potential for achieving high energy densities. However, the accumulation of insulating LiCl/NaCl on the porous cathode leads to passivation of the cathode and loss of capacity, resulting in a limited cycle life and lower power density. Herein, it is reported for the first time that pyridinic nitrogen in porous carbon undergoes a protonation reaction, transforming to a more active protonated pyridinic nitrogen configuration. This transformation induces charge retransfer and redistribution on the surface of the carbon material. A series of theoretical computations and in situ spectroscopic investigations reveals that protonated pyridinic nitrogen‐doped carbons have a lower nucleation barrier for LiCl/NaCl, which promotes uniform nucleation of LiCl/NaCl. As a result, the protonated pyridinic N‐doped carbon cathode achieves ultralong cycle stability (1500 cycles, 500 mAh g −1 , −20 °C) and an ultrahigh rate capability (up to 12 000 mA g −1 ). This study proves the effectiveness of heteroatom engineering in regulating C/Cl interactions and boosting the performance of Li/Na‐Cl 2 batteries.