Al–Fe–Si–La alloys for current collectors of positive electrodes in lithium ion batteries

Abstract

Al–xFe–Si–La alloys (x = 0.07, 0.2, 0.4 wt. %) were designed as current collectors of positive electrodes in lithium ion batteries, and the microstructure, tensile strength, electrical conductivity and corrosion resistance of the alloys were investigated with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), a tensile test, an electrical conductivity test, and an electrochemical test. It was found that the amount of Fe content greatly affected the quantity of the second phases in the alloys. The higher the Fe content was, the more the second phases were. With increase of the Fe content, the tensile strength and corrosion resistance of the Al–xFe–Si–La alloys were improved, and the electrical conductivity of the Al–xFe–Si–La alloys could meet the application requirements. Compared to the Al–0.07Fe–0.1Si–0.07La alloy, the strength of the Al–0.4Fe–0.1Si– 0.07La alloy was greatly enhanced. The Al–0.4Fe–0.1Si–0.07La alloy also had a higher corrosion potential than that of the Al–0.07Fe–0.1Si–0.07La alloy.