| 초록 |
The development of next generation storage devices greatly rely on high-energy density batteries. Metallic lithium electrodes holds the key for such devices due to the highest capacity (3860 mAh g-1), and lowest redox potential (-3.04 V). However, the dendritic and mossy lithium metal deposits, leads to serious safety concerns and low columbic efficiency during plating/stripping cycles, and have hindered their commercialization. Here, we propose graphene sheets (GS) modified current collector as a stable deposition host for metallic lithium electrode. The high surface area of GS can effectively reduce the local current density and guide uniform Li plating/stripping. Additionally several approaches has been adapted to further improve the Li metal electrode/electrolyte interface, good chemical stability and high mechanical strength. As proposed, GS modified current collector was characterized with XRD, SEM, TEM, and Raman techniques. Furthermore, the electrochemical performance of GS based metallic lithium electrode was studied systematically by varying Li depositing capacity and current density. As compared to bare current collector, the GS modified current collector displays a dendrite-less morphology and stable cyclic performance and higher Coulombic efficiency along with the deposition capacity. The current research provides some insights to control the dendrite formation and to improve the cycle life. |
