A vertically aligned carbon nanofiber (VACNF) array with unique conically stacked graphitic structure directly grown on a planar Cu current collector (denoted as VACNF/Cu) is used as a high‐porosity 3D host to overcome the commonly encountered issues of Li metal anodes. The excellent electrical conductivity and highly active lithiophilic graphitic edge sites facilitate homogenous coaxial Li plating/stripping around each VACNF and forming a uniform solid electrolyte interphase. The high specific surface area effectively reduces the local current density and suppresses dendrite growth during the charging/discharging processes. Meanwhile, this open nanoscale vertical 3D structure eliminates the volume changes during Li plating/stripping. As a result, highly reversible Li plating/stripping with high coulombic efficiency is achieved at various current densities. A low voltage hysteresis of 35 mV over 500 h in symmetric cells is achieved at 1 mA cm−2with an areal Li plating capacity of 2 mAh cm−2, which is far superior to the planar Cu current collector. Furthermore, a Li–S battery using a S@PAN cathode and a lithium‐plated VACNF/Cu (VACNF/Cu@Li) anode with slightly higher capacity (2 mAh cm−2) exhibits an excellent rate capability and high cycling stability with no capacity fading over 600 cycles.
- Award ID(s):
- 1922639
- NSF-PAR ID:
- 10357992
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 169
- Issue:
- 2
- ISSN:
- 0013-4651
- Page Range / eLocation ID:
- 020571
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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