Blocking pore design enables highly reversible lithium–chlorine batteries

Abstract

Rechargeable lithium–chlorine (Li–Cl₂) batteries are recognized as powerful candidates for energy storage due to high energy density and adaptability in harsh environments. However, porous materials used in Li–Cl₂ battery cathodes exhibit poor confinement of active chlorine species, which significantly challenges the rechargeability of batteries. Herein, we propose a blocking pore design to enable strong confinement and highly reversible conversion of chlorine species, where a narrow pore-entrance blocking effect confines LiCl growth in the pore body and suppresses Cl₂ spillage from the pores. As a result, the obtained Li–Cl₂ battery demonstrates a high gravimetric capacity of 3863 mAh g⁻¹, along with a super-long cycle life (750 cycles) and remarkable rate capability (616 mAh g⁻¹ at 30 A g⁻¹). This work presents a novel chlorine confinement mechanism to improve the reversibility of chlorine conversion in metal-chlorine batteries.