Wu Qiang, Qin Mingsheng, Yan Hui, Zhong Wei, Zhang Wei, Liu Mengchuang, Cheng Shijie, Xie Jia
State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China.
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China.
ACS Appl Mater Interfaces. 2022 Sep 21;14(37):42030-42037. doi: 10.1021/acsami.2c10920. Epub 2022 Sep 12.
In developing advanced lithium (Li) metal batteries with high-energy density, excellent cycle stability, and high-rate capability, it is imperative to resolve dendrite growth and volume expansion during repeated Li plating/stripping. 3D hosts featuring lithiophilic sites are expected to realize both spatial control and dendrite inhibition over Li nucleation. Herein, this work prepares silver (Ag) nanoparticle-decorated 3D copper (Cu) foam via a facile replacement reaction. The 3D host provides rigid skeleton to accommodate volume expansion during cycling. Ag nanoparticles show micro-structural affinity to guide efficient nucleation of Li, leading to reduced overpotential and enhanced electrochemical kinetics. As the result, under an ultrahigh current density of 10 mA cm, Cu@Ag foam/Li half cells demonstrate outstanding Coulombic efficiency (CE) of 97.2% more than 100 cycles. Also, Cu@Ag foam-Li symmetric cells sustain preeminent cycling over 900 h with a small voltage hysteresis of 32.8 mV at 3 mA cm. Moreover, the Cu@Ag foam-Li||LiFePO full cell demonstrates a high discharge capacity of 2.33 mAh cm over 200 cycles with an excellent CE up to 99.9% at 0.6C under practical conditions (N/P = 1.3, 17.4 mg cm LiFePO). Notably, the full cell with LiFePO exhibits a higher areal capacity of 1 mAh cm over 700 cycles under a high rate of 5C, corresponding to capacity retention up to 100% (N/P = 3, 17.4 mg cm LiFePO). This study provides a novel and simple strategy for constructing high-rate and long-life Li metal batteries.
在开发具有高能量密度、出色循环稳定性和高倍率性能的先进锂金属电池时，解决锂反复沉积/剥离过程中的枝晶生长和体积膨胀问题势在必行。具有亲锂位点的三维主体有望实现对锂成核的空间控制和枝晶抑制。在此，本工作通过简便的置换反应制备了银（Ag）纳米颗粒修饰的三维泡沫铜（Cu）。三维主体提供刚性骨架以适应循环过程中的体积膨胀。银纳米颗粒表现出微观结构亲和力，可引导锂的高效成核，从而降低过电位并增强电化学动力学。结果，在10 mA cm的超高电流密度下，Cu@Ag泡沫/Li半电池在100多个循环中展现出97.2%的出色库仑效率（CE）。此外，Cu@Ag泡沫-Li对称电池在3 mA cm下可稳定循环超过900 h，电压滞后仅为32.8 mV。而且，Cu@Ag泡沫-Li||LiFePO全电池在实际条件下（N/P = 1.3，17.4 mg cm LiFePO），在0.6C下200个循环中展现出2.33 mAh cm的高放电容量，出色的库仑效率高达99.9%。值得注意的是，配备LiFePO的全电池在5C的高倍率下700多个循环中展现出1 mAh cm的更高面积容量，容量保持率高达100%（N/P = 3，17.4 mg cm LiFePO）。本研究为构建高倍率、长寿命锂金属电池提供了一种新颖且简便的策略。
