Lithium metal battery

Abstract

In some aspects, the present disclosure provides a lithium metal battery having a negative electrode that comprises a substantially pure lithium metal and a positive electrode that comprises the epsilon polymorph of vanadyl phosphate (ε-VOPO4). The lithium metal can have less than five ppm of non-metallic elements by mass. The ε-VOPO4 can be made from solvothermally synthesized H2VOPO4, and be optimized to reversibly intercalate two Li-ions to reach full theoretical capacity with a coulombic efficiency of 98%. This material can adopt a stable 3D tunnel structure and can extract two Li-ions per vanadium ion, giving a theoretical capacity of 305 mAh/g, with an upper charge/discharge plateau at around 4.0 V, and one lower at around 2.5 V. The ε-VOPO4 particles may be modified with niobium (Nb) to improve the cycling stability.

Dependencies are inferred from the claim text.