Battery and fuel cell electrodes containing stainless steel charging additive

• US 4,448,856 A
• Filed: 03/14/1983
• Issued: 05/15/1984
• Est. Priority Date: 03/14/1983
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Department Of Energy
• Original Assignee: United States Department of Energy
• Inventors: Zuckerbrod, David, Gibney, Ann
• Primary Examiner(s): Walton, Donald L.
• Application Number:
  US06/474,933
• Time in Patent Office: 428 Days
• Field of Search: 429/27, 429/40, 429/44, 429/45, 429/42
• US Class Current: 429/406
• CPC Class Codes: H01M 4/86 Inert electrodes with catalytic activity, e.g. for fuel cells
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

An electrode for use in electrochemical energy cells is made, comprising a hydrophilic layer and a hydrophobic layer, where the hydrophilic layer comprises a hydrophilic composite which includes:

(i) carbon particles;

(ii) stainless steel particles;

(iii) a nonwetting agent; and

(iv) a catalyst, where at least one current collector contacts said composite.

Claims

1. An electrode comprising:

A. a hydrophilic layer comprising;

(1) a hydrophilic composite comprising;

i. 1 part by weight of carbon particles where at least about 50 wt.% of the carbon particles have a total surface area of from about 30 to about 300 sq. meters/gram;

ii. about 0.2 to about 1 part by weight of stainless steel particles;

iii. an effective amount of a bonding/nonwetting agent; and

iv. an effective amount of a catalyst for decomposition of perhydroxides; and

(2) at least one metal current collector contacting said composite to provide a hydrophilic layer, and

B. a hydrophobic layer pressed to said hydrophilic layer.

2. The electrode of claim 1, wherein the current collector is a metal fiber current collector, and the stainless steel particles have a particle size of from about 25 microns to about 420 microns.

3. The electrode of claim 1, wherein said hydrophilic composite is substantially flat, the catalyst is silver, and an effective amount of metal sulfide is included in the hydrophilic composite as a silver protective additive.

4. A metal/air cell comprising a metal electrode selected from the group consisting of iron, zinc, aluminum, and cadmium;

at least one air electrode as set forth in claim 1 spaced apart from said metal electrode; and

an alkali hydroxide electrolyte in contact with said electrodes.

5. A fuel cell, comprising a fuel electrode, an electrode as set forth in claim 1 spaced apart from said fuel electrode, and an alkali hydroxide electrolyte in contact with said electrodes.

8. The electrode of claim 5, wherein said hydrophilic composite is substantially flat, the catalyst is silver, the silver is deposited on the carbon particles, and an effective amount of metal sulfide is included in the hydrophilic composite as a silver protective additive.

6. An electrode for use in electrochemical energy cells comprising:

A. a hydrophilic layer comprising;

(1) a hydrophilic composite comprising;

i. 1 part by weight of carbon particles having a total surface area of from about 30 to about 1,500 sq. meters/gram, where at least about 50 wt.% of the carbon particles have a total surface are of from about 30 to about 300 sq. meters/gram;

ii. about 0.2 to about 1 part by weight of stainless steel particles having a particle size of from about 25 microns to about 420 microns;

iii. an effective amount of bonding/nonwetting agent including at least polytetrafluoroethylene; and

iv. an effective amount of a catalyst for decomposition of perhydroxides; and

(2) at least one metal current collector formed into said composite to provide a hydrophilic layer; and

B. A hydrophobic layer pressed to said hydrophilic layer.

7. The electrode of claim 6, wherein the current collector is a meter fiber current collector.

9. A metal/air cell comprising a metal electrode selected from the group consisting of iron, zinc, aluminum, and cadmium;

at least one electrode as set forth in claim 6 spaced apart from said metal electrode; and

an alkali hydroxide electrolyte in contact with said electrodes.

10. In a metal/air battery comprising a metal electrode selected from the group consisting of iron, zinc, cadmium, and aluminum, at least one air electrode spaced apart from said metal electrode, and an alkali electrolyte in contact with said metal and air electrode, the improvement consisting of the air electrode which comprises:

A. a hydrophobic sheet; and

B. a hydrophilic-active layer laminated to said hydrophobic sheet, said hydrophilic active layer comprising;

i. 1 part by weight of oxygen absorption/reduction carbon particles having a total surface area of from about 30 to about 1,500 sq. meters/gram, where at least about 50 wt.% of the carbon particles have a total surface area of from about 30 to about 300 sq. meters/gram;

ii. about 0.2 to about 1 part by weight of stainless steel particles having a particle size of from about 25 microns to about 420 microns;

iii. an effective amount of bonding/nonwetting agent including at least polytetrafluoroethylene;

iv. an effective amount of a catalyst for decomposition of perhydroxides; and

C. at least one metal current collector contacting said hydrophilic active layer.