Formulating the Electrolyte Towards High-Energy and Safe Rechargeable Lithium-Metal Batteries

Rechargeable lithium-metal batteries with a cell-level specific energy of >400 Wh kg^-1 are highly desired for next-generation storage applications, yet the research has been retarded by poor electrolyte-electrode compatibility and rigorous safety concerns. We demonstrate that by simply formulating the composition of conventional electrolytes, a hybrid electrolyte was constructed to ensure high (electro)chemical and thermal stability with both the Li-metal anode and the nickel-rich layered oxide cathodes. By employing the new electrolyte, Li∥LiNi_0.6 Co_0.2 Mn_0.2 O₂ cells show favorable cycling and rate performance, and a 10 Ah Li∥LiNi_0.8 Co_0.1 Mn_0.1 O₂ pouch cell demonstrates a practical specific energy of >450 Wh kg^-1 . Our findings shed light on reasonable design principles for electrolyte and electrode/electrolyte interfaces toward practical realization of high-energy rechargeable batteries.