▎ 摘　　要

NOVELTY - The method for improving lithium coating on the surface of a negative electrode involves: forming a coarsening layer on the surface of a negative electrode active material layer of a negative electrode, where the coarsening layer has a uniformly distributed nano-scale roughness; and compounding the ultrathin metal lithium or lithium alloy film with the thickness of 1-50 microm onto the coarsened layer under pressure to obtain the lithium-supplement negative electrode. USE - Method for improving lithium coating on the surface of a negative electrode used in lithium-ion secondary battery (claimed). ADVANTAGE - The coarsened layer on the surface of the negative electrode makes the metal lithium or lithium alloy easier to transfer to the surface of the negative electrode without incomplete transfer or crushing deformation of the negative electrode. The surface of the lithium-supplement negative electrode is flat (metal lithium is easy to deform, and the influence of a coarsened layer on the surface morphology is counteracted). When the lithium-supplementing negative electrode is soaked in electrolyte, metal lithium and a negative electrode active substance are completely reacted, and the coarsened layer does not influence the electrochemical performance. The preparation process of the lithium-supplement negative electrode is simple, easy to operate and can be applied to batch production. The lithium-supplementing negative electrode, the positive electrode and the diaphragm can be directly assembled into a battery for use by adopting a winding or lamination process, no additional working procedure is added, and the method is consistent with the existing process. The lithium-supplement negative electrode can improve the first efficiency of the secondary battery. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for the lithium-supplementing negative electrode. DESCRIPTION OF DRAWING(S) - The drawing shows a lithium-supplemented negative electrode.