US5500292A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymer electrolyte hydrogen-oxygen fuel cell where the polymer electrolyte has a water repellency gradient and a catalytically active component concentration gradiem across oxygen electrode
Assignee: Hitachi Ltd
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Filing: 1994-07-11
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Granted: 1996-03-19
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Expires: 2014-07-11
Abstract
Abstract The polymer electrolyte type hydrogen-oxygen fuel cell of the present invention comprises an oxygen electrode and a hydrogen electrode, a polymer electrolyte membrane provided between the oxygen electrode and hydrogen electrode and electron conductors provided on the side of the electrodes which is opposite to the electrolyte side and the oxygen electrode comprises a catalytically active component, a carrier for the catalytically active component and a binder and has such a gradient in water repellency across the thickness that the water repellency is highest in the area adjacent to the electrolyte and lowest in the area adjacent to the conductor. In this fuel cell, flooding of water at the interface between the oxygen electrode and the electrolyte can be prevented.
Inventors
- 👤 Yasushi Muranaka
- 👤 Jinichi Imahashi
- 👤 Tatsuo Horiba
- 👤 Shigeoki Nishimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:41
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/90; H01M4/92; H01M4/925; H01M4/926; H01M16/00; H01M16/003; H01M16/006; H01M8/00; H01M8/04; H01M8/04082; H01M8/04089; H01M8/04119; H01M8/10; H01M8/1004; H01M2300/00; H01M2300/0017; H01M2300/0065; H01M2300/0082; H01M8/04291; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
157 words
A polymer electrolyte, hydrogen-oxygen fuel cell comprising an oxygen electrode having a thickness and a hydrogen electrode which are a pair of gas-permeable electrodes, a polymer electrolyte membrane provided between said oxygen electrode and said hydrogen electrode and electron conductors provided respectively on an opposite side of said electrodes from the electrolyte membrane side, wherein said oxygen electrode comprises a catalytically active component, a carrier for the catalytically active component, and a binder, said oxygen electrode having such a gradient in water repellency across the thickness of the electrode that the water repellency is highest in the area adjacent to the electrolyte membrane and lowest in the area adjacent to the conductor and having such a gradient in the concentration of the catalytically active component across the thickness of the oxygen electrode that the concentration is highest in the area adjacent to the electrolyte membrane and is lowest in the area adjacent to the respective electron conductor.
Claim 2
Dependent Claim
157 words
A polymer electrolyte, hydrogen-oxygen fuel cell comprising an oxygen electrode having a thickness and a hydrogen electrode which are a pair of gas-permeable electrodes, a polymer electrolyte membrane provided between said oxygen electrode and said hydrogen electrode and electron conductors provided respectively on an opposite side of said electrodes from the electrolyte membrane side, wherein said oxygen electrode comprises a catalytically active component, a carrier for the catalytically active component, and a binder, said oxygen electrode having such a gradient in water repellency across the thickness of the electrode that the water repellency is highest in the area adjacent to the electrolyte membrane and lowest in the area adjacent to the conductor and having such a gradient in the concentration of the catalytically active component across the thickness of the oxygen electrode that the concentration is highest in the area adjacent to the electrolyte membrane and is lowest in the area adjacent to the respective electron conductor.
Claim 3
Dependent Claim
50 words
A fuel cell according to claim 1, wherein the oxygen electrode has such a gradient in porosity across the thickness of the electrode that the porosity in the area adjacent to the electrolyte membrane is equal to or higher than the porosity in the area adjacent to the electron conductor.
Claim 4
Dependent Claim
62 words
A fuel cell according to claim 1, wherein the oxygen electrode contains an ionic conductor comprising the material which is the same as or different from that of the electrolyte membrane and the concentration of the ionic conductor in the area adjacent to the electrolyte membrane is equal to or higher than the concentration in the area adjacent to the electron conductor.
Claim 5
Dependent Claim
30 words
A fuel cell according to claim 3, wherein the ionic conductor is an ion-exchange membrane comprising a perfluorosulfonic acid resin or a perfluorocarboxylic acid resin and the ion is proton.
Claim 6
Dependent Claim
38 words
A fuel cell according to claim 1, wherein the catalyst active component is at least one metal selected from the group consisting of metals belonging to platinum group and metals belonging to Group VI of the periodic table.
Claim 7
Dependent Claim
52 words
A fuel cell according to claim 1, wherein the binder is a water repellent comprising polytetrafluoroethylene, fluorinated graphite or a mixture thereof and is contained in the oxygen electrode in an amount which changes across the thickness of the oxygen electrode, thereby to give a gradient in water repellency to the electrode.
Claim 8
Dependent Claim
14 words
A power system having the fuel cell according claim 1 as an output source.
Claim 9
Dependent Claim
15 words
An electric automobile having the fuel cell according to claim 1 as an output source.
Claim 10
Dependent Claim
14 words
A secondary cell having the fuel cell according claim 1 as a charging source.
Claim 11
Dependent Claim
26 words
A fuel cell according to claim 1, wherein the polymer electrolyte membrane is an ion-exchange membrane comprising a perfluorosulfonic acid resin or a perfluorocarboxylic acid resin.
References Cited (Backward Citations)
US4175165A
Cited
FR2398392A1
Cited
JPS55113272A
Cited
JPS58204188A
Cited
US4543303A
Cited
DE3323491A1
Cited
US4444852A
Cited
JPS6035472A
Cited
US4931168A
Cited
US4876115A
Cited
US4804592A
Cited
JPH01143151A
Cited
JPH0286071A
Cited
JPH02260371A
Cited
JPH03102774A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-19 | 1999-09-18 | 2000-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-19 | 2003-09-18 | 2004-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-19 | 2007-09-18 | 2008-03-19 | $7700.00 | Window Closed / Lapsed |