COMPOSITE LITHIUM METAL NEGATIVE ELECTRODE, PREPARATION METHOD THEREFOR, AND SECONDARY LITHIUM BATTERY AND DEVICE

摘要

The present application relates to a composite lithium metal negative electrode, a preparation method therefor, and a secondary lithium battery and device. The composite lithium metal negative electrode provided in the present application comprises metallic lithium and a lithium buffer layer located on at least one surface of the metallic lithium. The lithium buffer layer comprises a porous framework and a lithium-philic material. The porous framework is an electrically conductive porous framework, the lithium-philic material is distributed in the porous framework, and the distribution density of the lithium-philic material in the porous framework decreases in a continuous gradient in a direction away from the metallic lithium. The present application adds the electrically conductive lithium buffer layer with a continuous gradient of lithium affinity onto the surface of the lithium metal negative electrode, which can provide sufficient migration channels for the deposition and dissolution of lithium ions, and can also induce uniform deposition of the metallic lithium in the lithium buffer layer, thereby inhibiting the formation of lithium dendrites and extending the cycle life of lithium metal batteries.