Self‐Supporting 3D Lithiophilic and Flexible Carbon Nanofiber Film as a High‐Loading Li Host

Abstract

Herein, a Zn and N co‐doped carbon nanofiber film (Zn–N–CNF) is successfully fabricated via a convenient electrospinning technique, which can be used as hybrid lithiophilic current collector to accommodate high‐loading lithium. Contributing to the lithiophilic active sites and 3D network structure of Zn–N–CNF, metallic Li can be reversibly electrochemical plated and stripped. Consequently, the Zn–N–CNF@Li electrode exhibits a high exchange current density of 4.731 mA cm−2, providing fast charge‐transfer kinetics for Li plating and stripping. Then, an average Coulombic efficiency of 97.3 % can be achieved at 1.0 mA cm−2 with 1.0 mAh cm−2 in 150 cycles. The corresponding symmetrical battery can stably cycle for nearly 800 h with a voltage hysteresis less than 20 mV at 0.5 mA cm−2 and 0.5 mAh cm−2. In addition, this flexible skeleton of 3D Zn–N–CNF can accommodate a high Li deposition capacity of 10 mAh cm−2 with a reversible electrochemical plating and stripping. Moreover, full cells based on the developed anode and a LiFePO4 cathode also demonstrate superior rate capability and stable cycle life. Herein, a promising strategy to construct dendrite‐free lithium metal anodes toward high‐performance lithium metal batteries is provided.

Keywords

• 3D carbon-based current collectors
• electrospinning techniques
• lithiophilic hosts
• metallic lithium anodes