CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China.
School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences (CAS), Beijing, 100049, P. R. China.
Adv Mater. 2018 Mar;30(10). doi: 10.1002/adma.201706216. Epub 2018 Jan 15.
The lithium metal anode has attracted soaring attention as an ideal battery anode. Unfortunately, nonuniform Li nucleation results in uncontrollable growth of dendritic Li, which incurs serious safety issues and poor electrochemical performance, hindering its practical applications. Herein, this study shows that uniform Li nucleation/growth can be induced by an ultralight 3D current collector consisting of in situ nitrogen-doped graphitic carbon foams (NGCFs) to realize suppressing dendritic Li growth at the nucleating stage. The N-containing functional groups guide homogenous growth of Li nucleus nanoparticles and the initial Li nucleus seed layer regulates the following well-distributed Li growth. Benefiting from such favorable Li growth behavior, superior electrochemical performance can be achieved as evidenced by the high Coulombic efficiency (≈99.6% for 300 cycles), large capacity (10 mA h cm , 3140 mA h g ), and ultralong lifespan (>1200 h) together with low overpotential (<25 mV at 3 mA cm ); even under a high current density up to 10 mA cm , it still displays low overpotential of 62 mV.
金属锂阳极作为一种理想的电池阳极受到了广泛关注。不幸的是，不均匀的 Li 成核导致枝晶 Li 的不可控生长，这引发了严重的安全问题和较差的电化学性能，阻碍了其实际应用。在此，本研究表明，通过由原位氮掺杂石墨碳泡沫（NGCFs）组成的超轻 3D 集流器可以诱导均匀的 Li 成核/生长，从而在成核阶段抑制枝晶 Li 的生长。含 N 的官能团引导 Li 核纳米颗粒的均匀生长，初始 Li 核种子层调节随后的均匀 Li 生长。得益于这种有利的 Li 生长行为，可以实现卓越的电化学性能，表现为高库仑效率（≈300 次循环中的 99.6%）、大容量（10 mA h cm ，3140 mA h g ）和超长寿命（>1200 h）以及低过电势（<25 mV，在 3 mA cm 下）；即使在高达 10 mA cm 的高电流密度下，它仍然显示出 62 mV 的低过电势。
