Metal-organic framework glass stabilizes high-voltage cathodes for efficient lithium-metal batteries
Lishun Bai, Yan Xu, Yue Liu, Danni Zhang, Shibin Zhang, Wujie Yang, Zhi Chang, Haoshen Zhou
Abstract
The rapid evolution of portable electronics and electric vehicles necessitates batteries with high energy density, robust cycling stability, and fast charging capabilities. High-voltage cathodes, like LiNi0.8Co0.1Mn0.1O2 (NCM-811), promise enhanced energy density but are hampered by poor stability and sluggish lithium-ion diffusion in conventional electrolytes. We introduce a metal-organic framework (MOF) liquid-infusion technique to fully integrate MOF liquid into the grain boundaries of NCM-811, creating a thoroughly coated cathode with a thin, rigid MOF Glass layer. The surface electrically non-conductive MOF Glass layer with 2.9 Å pore windows facilitating Li-ion pre-desolvation and enabling highly aggregative electrolyte formation inside the Glass channels, suppressing solvated Li-ion co-insertion and solvent decomposition. While the inner Glass layer composes of Li-ion conducting components and enhancing fast Li-ion diffusion. This functional structure effectively shields the cathode from particle cracking, CEI rupture, oxygen loss, and transition metal migration. As a result, Li | |Glass@NCM-811 cells demonstrate good rate capability and cycling stability even under high-charge rates and elevated voltages. Furthermore, we also achieve a 385 Wh kg-1 pouch-cell (19.579 g, for pouch-cell), showcasing the practical potential of this method. This straightforward and versatile strategy can be applied to other high-voltage cathodes like Li-rich manganese oxides and LiCoO2. Li-ion batteries based on high-voltage Ni-rich layered oxides are hampered by stability and ion diffusion issues. Here, authors develop a metal-organic-framework liquid-infusion technique to create a rigid glass layer on the oxide particles, improving both Li+ diffusion and battery stability.