Metal lithium negative electrode with dual-layer structure

Abstract

The invention relates to a metal lithium negative electrode with a dual-layer structure. The metal lithium negative electrode comprises a metal lithium layer at a bottom layer and a surface cover layer at an upper layer. In the metal lithium negative electrode, a surface layer structure on the surface can be used for controlling distribution of lithium ions on the surface of the negative electrode, the lithium ions are prevented from being gathered in time and space, and the uniform distribution of the lithium ions on the surface of the negative electrode is achieved, so that dendritic crystal is prevented. The control behavior of the surface layer structure of the metal lithium negative electrode on the lithium ions is achieved by a material having a relatively high absorption effect on the lithium ions. Compared with a metal lithium negative electrode without the dual-layer structure, the metal lithium negative electrode with the dual-layer structure has the advantages that the growth of lithium dendritic crystal can be prevented, the safety of the metal lithium negative electrode can be ensured, the energy utilization ratio of the battery can be relatively and substantially improved, and the cycle lifetime of the battery can be relatively and substantially prolonged. If the metal lithium negative electrode is used with a high-capacity positive electrode material in a matching way, the practical progress of a novel high-energy density lithium battery can be promoted.

Description

field of invention [0001] The invention relates to a negative pole of a lithium battery, in particular to a metal lithium negative pole with a double-layer structure. Background technique [0002] Compared with graphite anodes currently commercially used in lithium-ion batteries, lithium metal anodes can theoretically provide more capacity (3860mAh g -1 , Graphite negative electrode: 372mAh·g -1 ) and the most negative potential (-3.040V vs. standard hydrogen electrode, graphite negative electrode: ~1.0V vs. Li + / Li), it is expected to achieve larger applications in the next generation of portable electronic devices and electric vehicles. Lithium-sulfur batteries and lithium-air batteries using metallic lithium as the negative electrode have gradually attracted the attention of researchers, and have become a hot spot in academic and industrial research in recent years. However, there are still many problems in the research of lithium metal anodes, the most important of w...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to change the problems of easy growth of dendrites, low safety, and poor cycle performance in the current use of metal lithium negative electrodes, by using materials that have a strong interaction with lithium ions as the surface layer of metal negative electrodes to achieve dendrite suppression. Crystal growth, stable lithium metal negative electrode, thereby improving battery energy utilization and cycle life