Li‐N2 Batteries: A Reversible Energy Storage System?

Abstract Tremendous energy consumption is required for traditional artificial N2 fixation, leading to additional environmental pollution. Recently, new Li‐N2 batteries have inextricably integrated energy storage with N2 fixation. In this work, graphene is introduced into Li‐N2 batteries and enhances the cycling stability. However, the instability and hygroscopicity of the discharge product Li3N lead to a rechargeable but irreversible system. Moreover, strong nonpolar N≡N covalent triple bonds with high ionization energies also cause low efficiency and irreversibility of Li‐N2 batteries. In contrast, the modification with in situ generated Li3N and LiOH restrained the loss and volume change of Li metal anodes during stripping and plating, thereby promoting the rechargeability of the Li‐N2 batteries. The mechanistic study here will assist in the design of more stable Li‐N2 batteries and create more versatile methods for N2 fixation.