Lithium metal is most attractive anode material for high-energy-density Li-ion battery. However, the strong reducing nature of lithium metal results in poor stability and low coulombic efficiency in lithium batteries. Despite decades of research efforts to stabilize lithium metal anode, the development of lithium battery is still greatly impeded by the lack of knowledge about lithium-stable materials chemistry. So far, only a few materials are known to be stable against Li metal.
We will present our recent work, which provides novel strategies of using nitrides to stabilize lithium metal anode. We uncovered many lithium-stable materials out of chemistry across the periodic table, by using first-principles calculations based on large materials database. We found that most oxides, sulfides, and halides, which were commonly studied as protection materials, are reduced by lithium metal due to the reduction of metal cations. On the contrary, nitride anion chemistry exhibits unique stability against Li metal, which is either thermodynamically intrinsic or a result of stable passivation. Many nitrides materials, which were rarely investigated as lithium metal protection materials before, can be promising candidate lithium metal protection materials to achieve long-term stability.
Our work established essential guidelines for selecting, designing, and discovering materials for lithium metal protection. In addition, we also proposed multiple novel strategies of using nitride materials and high nitrogen doping to form stable solid-electrolyte-interphase for lithium metal anode. Our computation results provide novel guidance and strategies for stabilizing lithium metal anode and would contribute to the development of high-energy-density rechargeable lithium batteries.