High-voltage lithium-metal battery with three-dimensional mesoporous carbon anode host and ether/carbonate binary electrolyte

Electrolyte recipes and Li metal anode host materials are developed for lithium-metal batteries. 1,2-dimethoxyethane/ethylene carbonate mixed solvent with 1 M lithium bis(fluorosulfonyl)imide and 1 wt% LiNO₃ is shown to form a robust solid electrolyte interphase and improve Coulombic efficiency and cyclability during Li metal plating/stripping. This electrolyte can withstand high potential, allowing the operation of a LiNi_0.8Co_0.1Mn_0.1O₂ (NMC-811) cathode. One-dimensional carbon nanotubes, two-dimensional graphene nanosheets, and three-dimensional ordered mesoporous carbon CMK-8 are used as the host materials for the accommodation of Li metal. The strong and continuous conducting network of CMK-8 with interpenetrating open channels is found to be a promising scaffold for Li metal. With the proposed electrolyte, the CMK-8 electrode enables uniform Li plating/stripping with a high Coulombic efficiency of 99.2% under a practical current density of 1 mA cm⁻². Moreover, a long life of >550 charge-discharge cycles is achieved. The high structural stability of CMK-8 upon cycling is confirmed using electron microscopy and Raman spectroscopy. Finally, we use a Li-free CMK-8 electrode, an NMC-811 cathode, and the proposed electrolyte to construct a full cell. The electrochemical properties are evaluated.