Shu Miao, Li Xing, Duan Liqiang, Zhu Mengting, Xin Xing
School of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, China.
Nanoscale. 2020 Apr 30;12(16):8819-8827. doi: 10.1039/d0nr01111h.
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.
锂（Li）金属因其高比容量（3860 mA h g-1）和低氧化还原电位（相对于标准氢电极，-3.04 V），被认为是新一代锂电池最具前景的负极材料。然而，电池循环过程中锂枝晶的形成不仅会导致性能不佳，如库仑效率低和循环寿命短，还会带来严重的安全风险，如火灾和爆炸。在本文中，我们提出了一种具有三维网络结构的新型中间层，该网络富含含氮官能团和钴纳米颗粒，以引导锂均匀成核/生长，从而缓解锂枝晶的形成。结果，所设计的复合材料在对称电池中实现了1500小时的超长寿命，电压分布小且稳定，仅为38.1 mV。该复合电极在以磷酸铁锂为正极的锂离子电池全电池中也表现出卓越的电化学性能。我们的研究结果为通过引入亲锂位点诱导锂的均匀成核提供了有力支持，这对于抑制锂枝晶的形成至关重要。
