Surface engineering of commercial Ni foams for stable Li metal anodes
Surface engineering of commercial Ni foams for stable Li metal anodes
复制标题
DOI：
10.1016/j.ensm.2019.04.003
复制
发表时间：
2019-12-01
影响因子：
20.4
通讯作者：
Shi, Zhicong
中科院分区：
文献类型：
--
作者：
Ke, Xi;Liang, Yaohua;Shi, Zhicong
锂金属阳极（LMA）由于枝晶生长和低库仑效率（CE）而导致的短寿命已被认为是开发下一代高能量密度锂金属基二次电池的瓶颈。采用三维（3D）集电器是降低有效电流密度和延迟枝晶生长的一种方法。商业镍泡沫尽管具有高电子传导性和3D拓扑结构，但由于其低比表面积和疏锂性质，尚未考虑用于该应用。在这项研究中，我们开发了一种表面工程的策略，通过锂化的电沉积的金纳米颗粒均匀地涂覆在镍泡沫骨架上的亲锂AuLi 3颗粒。与裸Ni泡沫相比，AuLi3@Ni泡沫更亲锂，显著降低了成核能垒并提高了Li沉积的均匀性。这样的结构导致有效抑制泡沫的空隙空间中的Li枝晶生长。结果，基于AuLi3@Ni泡沫集流体的LMA可以在对称电池中运行740 h而没有电池失效。此外，Li-AuLi 3 @Ni泡沫竖条LiFePO 4全电池在1C下500次循环显示出43.8%的优异容量保持率和99.2%的高CE。这项工作进一步说明了表面亲锂性在引导锂循环中的至关重要性，并表明工程化商业金属泡沫集流体的骨架表面对于改善3D结构的LMA是重要的。
The short life span of lithium metal anodes (LMAs) due to dendrite growth and low coulombic efficiency (CE) has been regarded as the bottleneck in developing next-generation high-energy-density lithium metal based secondary batteries. Employing three-dimensional (3D) current collectors is one approach to reduce the effective current density and delay dendrite growth. Commercial Ni foam, in spite of its high electronic conductivity and 3D topology, has not been considered for this application due to its low specific surface area and lithiophobic nature. In this study, we develop a surface engineering strategy to uniformly coat lithiophilic AuLi3 particles on Ni foam skeletons through lithiation of electrodeposited gold nanoparticles. In comparison with the bare Ni foam, the AuLi3@Ni foam is more lithiophilic, significantly lowering the nucleation energy barrier and enhancing the uniformity for Li deposition. Such a structure results in effective suppression of Li dendrite growth in the void space of the foam. As a result, the AuLi3@Ni foam current collector based LMAs can run for 740 h without cell failure in a symmetric cell. Furthermore, the Li-AuLi3@Ni foam vertical bar LiFePO4 full cell shows an excellent capacity retention of 43.8% with a high CE of 99.2% at 1C for 500 cycles. This work further illustrates the critical importance of surface lithiophilicity in guiding lithium cycling and suggests engineering the skeleton surface of commercial metal foam current collectors is important to improve 3D structured LMAs.