Surface treatment method and device for hydrogen absorbing alloy powder

Patent metadata

Field	Value
Publication number	US-12134129-B2
Application number	US-202217667068-A
Country	US
Kind code	B2
Filing date	Feb 8, 2022
Priority date	Mar 1, 2021
Publication date	Nov 5, 2024
Grant date	Nov 5, 2024

Abstract

A surface treatment method for a hydrogen absorbing alloy powder of the present disclosure is used for a surface treatment on a hydrogen absorbing alloy powder containing rare earth elements and nickel as constituent elements, including an immersion process in which the hydrogen absorbing alloy powder is immersed in an aqueous alkaline solution; and a removal process in which a liquid containing the hydrogen absorbing alloy powder immersed in the aqueous alkaline solution is introduced into a liquid cyclone, and undesired substances having a smaller specific gravity than the hydrogen absorbing alloy powder adhered to the surface of the hydrogen absorbing alloy powder are removed.

First claim

What is claimed is:

1. A surface treatment method for a hydrogen absorbing alloy powder containing rare earth elements and nickel as constituent elements, comprising:
immersing the hydrogen absorbing alloy powder in an aqueous alkaline solution;
bringing the hydrogen absorbing alloy powder into contact with an oxidant such that hydrogen is desorbed from the hydrogen absorbing alloy powder while the hydrogen absorbing alloy powder is immersed in the aqueous alkaline solution; and
introducing the liquid containing the hydrogen absorbing alloy powder into a liquid cyclone such that undesired substances having a smaller specific gravity than the hydrogen absorbing alloy powder adhered to the surface of the hydrogen absorbing alloy powder are removed in the liquid cyclone, after the hydrogen absorbing alloy powder is brought into contact with the oxidant.

2. The method according to claim 1 ,
wherein the liquid cyclone includes a liquid inlet, a lower outlet through which particles having a larger specific gravity are discharged, and an upper outlet through which particles having a smaller specific gravity are discharged, and
wherein, water is applied to the hydrogen absorbing alloy powder discharged from the lower outlet of the liquid cyclone and introduced again to the liquid inlet.

Assignees

• Toyota Motor Co Ltd

Inventors

• Kodama Masashi
• Okumura Motoyoshi

Classifications

• B22F2202/17

  use of centrifugal or vortex forces · CPC title

• B22F2301/155

  Rare Earth - Co or -Ni intermetallic alloys · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title

• H01M10/30

  Nickel accumulators (H01M10/34 takes precedence) · CPC title

• B22F2202/15

  Use of fluidised beds · CPC title