Copper-zinc alloy current collector for inhibiting lithium dendrites

Abstract

The invention relates to a copper-zinc alloy current collector for inhibiting lithium dendrites. A conventional current collector is covered with a layer of copper-zinc alloy, the thickness of the copper-zinc alloy is 10 nm to 1 [mu]m, and the zinc atom content of the copper-zinc alloy is 1-5%. The copper-zinc alloy current collector provides more active sites for lithium metal deposition than theconventional current collector, and a button battery is assembled in a glove box full of argon by using a metal lithium-loaded alloy current collector or a common copper foil as a negative electrodeand adopting a Celgard 2325 diaphragm and metallic lithium as a reference electrode and a counter electrode. Deposition / dissolution experiments are carried out with blue electricity. The current density is 0.5 mA cm<-2>, the voltage lag is significantly increased after the copper foil electrode only circulates for 520 h, and a copper-zinc alloy negative electrode still maintains a small voltage lag after 1000 h circulation. The current collector in the invention is applied to a lithium-lithium iron phosphate a battery, and the electrochemical performances of the battery are obviously better than those of a battery using a metallic lithium negative electrode adopting the common current collector.

Description

technical field [0001] The invention relates to a copper-zinc alloy current collector suppressing lithium dendrites, which is applied to the field of high-energy storage metal lithium batteries. Background technique [0002] With the rapid development of electric vehicles, mobile phones, notebook computers and other industries, people's demand for energy storage batteries with high energy density and high safety is increasing. In various battery systems, metallic lithium has the highest theoretical specific energy (3860mAh g -1 ) and the lowest redox electrode potential (-3.040V vs. standard hydrogen electrode), which has become a research hotspot for the next generation of battery anode materials. However, lithium metal anodes tend to form needle-like or dendritic lithium dendrites during charging and discharging. The formation and growth of lithium dendrites will bring irreversible capacity loss to the battery system, and may even pass through the separator to cause an i...

AI Technical Summary

Problems solved by technology

Due to the surface unevenness and defects of the commonly used copper foil current collectors, metal lithium will be enriched unevenly during the nucleation stage, which will greatly increase the probability of lithium dendrites.

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