The application discloses a composite
lithium-
magnesium alloy negative
electrode and a preparation and application thereof. After a fluorinated
copolymer solution is uniformly loaded on the surface of a three-dimensional conductive framework, the three-dimensional conductive framework is combined with a
lithium-
magnesium alloy foil in a sandwich arrangement mode, and then the combination is obtained through mechanical rolling. The three-dimensional conductive framework material effectively reduces the size of the
local current density, and can also provide sufficient
accommodation space for the deposition of
metal lithium. The elastic self-adaptive interface rich in LiF formed by using the fluorinated
copolymer can accelerate the
ion transmission at the interface and maintain the stability in a long cycle process. The lithium-
magnesium alloy with the lithium affinity induces the uniform deposition of lithium ions, and the growth of dendrites is inhibited, so that the composite lithium-
magnesium alloy negative
electrode material with the
fluorine-rich lithium elastic self-adaptive interface is constructed.