Nitrogen-doped polymer nanofibers decorated with Co nanoparticles for uniform lithium nucleation/growth in lithium metal batteries

Abstract

Lithium (Li) metal is deemed to be the most promising anode for new-generation lithium batteries due to its high specific capacity (3860 mA h g⁻¹) and low redox potential (−3.04 V vs. SHE). However, Li dendritic formation during battery cycling results not only in poor performance, such as low coulombic efficiency and short cycling, but also serious safety risks such as fire and explosion. In this paper, we propose a novel interlayer with a 3D network which is rich in N-containing functional groups and Co nanoparticles to guide uniform Li nucleation/growth and thus relieve the Li dendritic formation. As a result, the as-designed composite delivers an ultra-long lifespan of 1500 h with a small and stable voltage profile of 38.1 mV for symmetric cells. The composite electrode also exhibits a prominent electrochemical performance in full cells with LiFePO₄ as the cathode for lithium ion batteries (LIBs). Our findings provide strong support for inducing the uniform nucleation of Li by introducing lithiophilic sites, which is important for inhibiting Li dendritic formation.