Hydrogen storing alloy, electrode, and nickel-hydrogen storage battery

Patent metadata

Field	Value
Publication number	US-2016090643-A1
Application number	US-201514866070-A
Country	US
Kind code	A1
Filing date	Sep 25, 2015
Priority date	Sep 30, 2014
Publication date	Mar 31, 2016
Grant date	—

Abstract

Provided is a hydrogen storing alloy represented by the general formula:
(RE 1-a-b Sm a Mg b )(Ni 1-c-d Al c M d ) x (where 0.3<a<0.6; 0<b<0.16; 0.1<cx<0.2; 0≦dx≦0.1; 3.2<x<3.5; RE is at least one element selected from the group consisting of a rare earth element other than Sm, and Y, and essentially contains La; and M is Mn and/or Co). Also provided is a hydrogen storing alloy represented by the general formula: (RE 1-a-b Sm a Mg b )(Ni 1-c-d Al c M d ) x (where 0.1<a<0.25; 0.1<b<0.2; 0.02<cx<0.2; 0≦dx≦0.1; 3.6<x<3.7; RE is at least one element selected from the group consisting of a rare earth element other than Sm, and Y, and essentially contains La; and M is Mn and/or Co). Further provided is a nickel-metal hydride rechargeable battery including a negative electrode containing the hydrogen storing alloy.

First claim

What is claimed is:

1 . A hydrogen storing alloy represented by the general formula:
(RE 1-a-b Sm a Mg b )(Ni 1-c-d Al c M d ) x (where 0.3<a<0.6; 0<b<0.16; 0.1<cx<0.2; 0≦dx≦0.1; 3.2<x<3.5; RE is at least one element selected from the group consisting of a rare earth element other than Sm, and Y, and essentially contains La; and M is Mn and/or Co).

2 . The hydrogen storing alloy according to claim 1 , wherein the content of La in RE is 0.3 or more in terms of a molar amount based on the total amount of RE, Sm and Mg.

3 . A hydrogen storing alloy represented by the general formula:
(RE 1-a-b Sm a Mg b )(Ni 1-c-d Al c M d ) x (where 0.1<a<0.25; 0.1<b<0.2; 0.02<cx<0.2; 0≦dx≦0.1; 3.6<x<3.7; RE is at least one element selected from the group consisting of a rare earth element other than Sm, and Y, and essentially contains La; and M is Mn and/or Co).

4 . The hydrogen storing alloy according to claim 3 , wherein the content of La in RE is 0.6 or more in terms of a molar amount based on the total amount of RE, Sm and Mg.

5 . The hydrogen storing alloy according to claim 1 , wherein RE contains Nd and/or Pr.

6 . The hydrogen storing alloy according to claim 2 , wherein RE contains Nd and/or Pr.

7 . The hydrogen storing alloy according to claim 3 , wherein RE contains Nd and/or Pr.

8 . The hydrogen storing alloy according to claim 4 , wherein RE contains Nd and/or Pr.

9 . The hydrogen storing alloy according to claim 1 , wherein the hydrogen storing alloy contains 70% by mass or more of a Ce 2 Ni 7 phase as a crystal phase of the alloy.

10 . The hydrogen storing alloy according to claim 2 , wherein the hydrogen storing alloy contains 70% by mass or more of a Ce 2 Ni 7 phase as a crystal phase of the alloy.

11 . The hydrogen storing alloy according to claim 5 , wherein the hydrogen storing alloy contains 70% by mass or more of a Ce 2 Ni 7 phase as a crystal phase of the alloy.

12 . The hydrogen storing alloy according to claim 6 , wherein the hydrogen storing alloy contains 70% by mass or more of a Ce 2 Ni 7 phase as a crystal phase of the alloy.

13 . The hydrogen storing alloy according to claim 3 , wherein the hydrogen storing alloy contains 80% by mass or more of a Pr 5 Co 19 phase and Ce 5 Co 19 phase as a crystal phase of the alloy.

14 . The hydrogen storing alloy according to claim 4 , wherein the hydrogen storing alloy contains 80% by mass or more of a Pr 5 Co 19 phase and Ce 5 Co 19 phase as a crystal phase of the alloy.

15 . The hydrogen storing alloy according to claim 7 , wherein the hydrogen storing alloy contains 80% by mass or more of a Pr 5 Co 19 phase and Ce 5 Co 19 phase as a crystal phase of the alloy.

16 . The hydrogen storing alloy according to claim 8 , wherein the hydrogen storing alloy contains 80% by mass or more of a Pr 5 Co 19 phase and Ce 5 Co 19 phase as a crystal phase of the alloy.

17 . An electrode comprising the hydrogen storing alloy according to claim 1 .

18 . An electrode comprising the hydrogen storing alloy according to claim 3 .

19 . A nickel-metal hydride rechargeable battery comprising the electrode according to claim 17 as a negative electrode.

20 . A nickel-metal hydride rechargeable battery comprising the electrode according to claim 18 as a negative electrode.

Assignees

• Gs Yuasa Int Ltd

Inventors

• Okuda Daisuke
• Kanemoto Manabu
• Kodama Mitsuhiro

Classifications

• H01M10/345

  Gastight metal hydride accumulators · CPC title

• H01M4/383

  Hydrogen absorbing alloys · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• C22C19/03 Primary

  based on nickel · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title