Wu Li-Na, Peng Jun, Sun Ya-Ke, Han Fa-Ming, Wen Yan-Fen, Shi Chen-Guang, Fan Jing-Jing, Huang Ling, Li Jun-Tao, Sun Shi-Gang
ACS Appl Mater Interfaces. 2019 May 22;11(20):18504-18510. doi: 10.1021/acsami.9b05053. Epub 2019 May 7.
Lithium (Li) metal is a favorable anode for most energy storage equipment, thanks to its higher theoretical specific capacity. However, nonuniform Li nucleation/growth results in large-sized and irregular dendrites generated from the Li anode, which causes rapid capacity fade and serious safety hazard, hindering its widespread practical applications. In this paper, with the aid of a lithium nitrate (LiNO) additive in a carbonate-based electrolyte, the Li anode shows low hysteresis for in excess of 1000 h at a current density of 0.5 mA cm. At the same time, a Li-graphite dual-ion battery exhibits an outstanding cycling stability at 5C; after 1000 cycles, 81% of the capacity is retained. After calculation, the Li-graphite dual-ion battery shows a competitive specific energy density of 243 Wh kg at a power density of 234 W kg. Moreover, the linear sweep voltammetry test was first performed to analyze the Li nucleation/growth mechanism and explain the effect of the LiNO additive. The superior electrochemical properties of the Li-graphite dual-ion battery are ascribed to the formation of smooth Li composed of Li nanoparticles and a steady solid electrolyte interface film.
锂（Li）金属因其较高的理论比容量，是大多数储能设备理想的负极材料。然而，锂的非均匀成核/生长会导致锂负极产生大尺寸且不规则的枝晶，这会导致容量快速衰减并带来严重的安全隐患，阻碍了其广泛的实际应用。在本文中，通过在碳酸盐基电解质中添加硝酸锂（LiNO₃），锂负极在0.5 mA cm²的电流密度下表现出超过1000小时的低滞后现象。同时，锂-石墨双离子电池在5C下表现出出色的循环稳定性；经过1000次循环后，仍保留81%的容量。经计算，锂-石墨双离子电池在功率密度为234 W kg⁻¹时，具有243 Wh kg⁻¹的竞争比能量密度。此外，首次进行线性扫描伏安法测试以分析锂的成核/生长机制，并解释LiNO₃添加剂的作用。锂-石墨双离子电池优异的电化学性能归因于由锂纳米颗粒组成的光滑锂和稳定的固体电解质界面膜的形成。
