Rare earth-magnesium-nickel system heterogeneous hydrogen storage alloys used for nickel-hydrogen batteries and preparing method thereof

Abstract

The invention discloses rare earth-magnesium-nickel system heterogeneous hydrogen storage alloys used for nickel-hydrogen batteries and a preparing method thereof. The alloys are characterized in that: the general structure formula of the alloys is LnMgNi<x>Y<y>Z<z>, wherein the Ln is at least one element selected from rare earth elements; the Y is at least one element selected from a group comprising Co, Mn, Al, Cu, Nb, V, Fe, Zn, Ti, Cr, As, Ga, Mo, Sn, In, W, Si, B and P; the Z is at least one element selected from a group comprising Ag, Sr, Ge and Au; the a is less than 1 and not less than 0.5; the b is less than 0.5 and more than 0; the x is more than 2.5 and less than 4.5; the y is more than 0 and less than 2; the z is more than 0 and not more than 1; an AB5 phase accounts for 10-90%; an A2B7 phase accounts for 10-90%; and the ratio of other impurity phases is not more than 30%. B side elements are replaced by the Ag, the Sr, the Ge, the Au, and the like, alloy components and an annealing process are optimized, and the ratio of the AB5 phase to the A2B7 phase in the product is adjusted, thus increasing the discharge capacity of the hydrogen storage alloy, prolonging the cycle lifetime of the hydrogen storage alloy, and improving self-discharge and low-temperature properties.

Description

Technical field: [0001] The invention belongs to the technical field of batteries and battery hydrogen storage materials, and in particular relates to a rare earth-magnesium-nickel hydrogen storage alloy for nickel-hydrogen batteries and a preparation method thereof. Background technique: [0002] With the continuous deterioration of the global environment, the demand for cost-effective secondary energy is becoming increasingly urgent. Ni-MH batteries have the advantages of environmental protection, high specific energy density, good safety, long cycle life, fast charging, no memory effect, and reasonable price. They have been widely used in military equipment, electric tools, household appliances and other fields. The automotive sector exhibits a huge market advantage. The anode materials of nickel metal hydride batteries used commercially are mainly rare earth series AB 5 type hydrogen storage alloy to LaNi 5 As a representative, the alloy is easy to pulverize, has low ...

AI Technical Summary

Problems solved by technology

Rare earth elements such as Ce, Pr, and Nd are mostly used for replacement on the A side, and the high price of Pr and Nd affects the price of the final product

Images