Modified electrochemical hydrogen storage alloy having increased capacity, rate capability and catalytic activity

• US 6,270,719 B1
• Filed: 04/12/1999
• Issued: 08/07/2001
• Est. Priority Date: 04/12/1999
• Status: Expired due to Term

• Current Assignee: Chevron Texaco Corporation (Chevron Corp.)
• Original Assignee: Ovonic Battery Company, Inc (BASF SE)
• Inventors: Mays, William, Reichman, Benjamin, Ovshinsky, Stanford R., Fetcenko, Michael A., Koch, John, Young, Kwo
• Primary Examiner(s): SHEEHAN, JOHN P
• Application Number:
  US09/290,633
• Time in Patent Office: 848 Days
• Field of Search: 148/421, 148/422, 148/426, 148/427, 148/428, 148/429, 148/442, 420/900, 420/417, 420/418, 420/420, 420/421, 420/424, 420/422, 420/441, 420/442, 420/446, 420/449, 420/451, 420/460, 420/580, 420/588, 429/57, 429/101
• US Class Current: 420/588
• CPC Class Codes: C01B 3/0031 Intermetallic compounds; Metal alloys; Treatment thereof
• CPC Class Codes: C22C 14/00 Alloys based on titanium
• CPC Class Codes: C22C 16/00 Alloys based on zirconium
• CPC Class Codes: C22C 27/025 alloys based on vanadium
• CPC Class Codes: C22C 27/06 Alloys based on chromium
• CPC Class Codes: H01M 4/383 Hydrogen absorbing alloys
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• CPC Class Codes: Y10S 420/90 Hydrogen storage
• CPC Class Codes: Y10T 428/12104 Particles discontinuous

Abstract

A modified Ti—V—Zr—Ni—Mn—Cr electrochemical hydrogen storage alloy which has at least one of the following characteristics: 1) an increased charge/discharge rate capability over that the base Ti—V—Zr—Ni—Mn—Cr electrochemical hydrogen storage alloy; 2) a formation cycling requirement which is reduced to one tenth that of the base Ti—V—Zr—Ni—Mn—Cr electrochemical hydrogen storage alloy; or 3) an oxide surface layer having a higher electrochemical hydrogen storage catalytic activity than the base Ti—V—Zr—Ni—Mn—Cr electrochemical hydrogen storage alloy.

Claims

1. A hydrogen storage alloy consisting of, in atomic percentage 0.1 to 60% Ti, 0.1 to 40% Zr, 0<

V<

60%, 0.1 to 57% Ni, 5 to 22% Mn, 0<

Cr<

56, Sn, Al, Co and optionally Fe.

2. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 1, further comprising 0.1 to 10.0% Al, 0.1 to 10.0% Co, 0 to 3.5% Fe and 0.1 to 3.0% Sn.

3. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 2, comprising, in atomic percentage, Ti 9.0%, Zr 26.2%, V 5.0%, Ni 38.0%, Cr 3.5%, Co 1.5%, Mn 15.6%, Al 0.4%, and Sn 0.8%.

4. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 1, wherein said oxide layer contains metallic catalytic particles of from 10-50 Angstroms in size dispersed therein.

5. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 4, wherein said metallic catalytic particles are from 10-40 Angstroms in size.

6. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 5, wherein said metallic catalytic particles are from 10-30 Angstroms in size.

7. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 6, wherein said metallic catalytic particles are from 10-20 Angstroms in size.

8. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 7, wherein said metallic catalytic particles are Ni—

Mn—

Co—

Ti alloy catalytic particles.

9. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 4, wherein said metallic catalytic particles are finely dispersed in said oxide from 10-20 Angstroms apart.

10. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 4, wherein said metallic catalytic particles have an FCC crystalline structure.

11. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 4, wherein said metallic catalytic particles have a NiCoMnTi and TiZr oxide support structure forming a super lattice to promote ionic diffusion and reaction.

12. A modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy comprising, in atomic percentage;

13. The modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 12 comprising, in atomic percentage, Ti 9.0%, Zr 26.2%, V 5.0%, Ni 38.0%, Cr 3.5%, Co 1.5%, Mn 15.6%, Al 0.4%, and Sn 0.8%.

14. In a method of casting an ingot of a modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy comprising, in atomic percentage (Base Alloy)_aCo_bFe_cAl_dSn_e, where said Base Alloy comprises 0.1 to 60% Ti, 0.1 to 40% Zr, 0<

V<

60% , 0.1 to 57% Ni, 5 to 22% Mn and 0 to 56% Cr;

b is 0.1 to 10.0%;

c is 0 to 3.5%;

d is 0.1 to 10.0%;

e is 0.1 to 3.0%; and

a+b+c+d+e=100% the improvement comprising;

limiting the ingot thickness to less than about 5 inches.

15. The method of casting an ingot of a modified Ti—

V—

Zr—

Ni—

Mn—

Cr electrochemical hydrogen storage alloy of claim 14, further comprising limiting the ingot thickness to less than about one inch.