Patent US4117202A successfully refreshed from Google Patents.
US4117202A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solar powered biological fuel cell
Assignee: Individual
•
Filing: 1977-06-14
•
Granted: 1978-09-26
•
Expires: 1997-06-14
Abstract
Abstract A solar powered biological fuel cell is provided which is capable of generating a direct electric current in response to incident solar energy. The cell includes a suspension of mesophyll cells isolated from Digitaria sanguinalis (crab grass), malic enzyme, a nicotinamide adenine dinucleotide, a xanthine oxidase enzyme, a potential mediator such as benzyl viologen or methylene blue, and a catalyst such as pyruvate in an aqueous solution; and an appropriate electrode assembly.
Inventors
- 👤 Timothy A. Beck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:14
CPC Classifications
H; H01; H01M; H01M8/00; H01M8/16; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
140 words
A photosynthetically-driven biological fuel cell comprising: means forming a growth chamber having a transparent top exposed to sunlight; a nutrient aqueous solution contained in said growth chamber; an anode electrode and a cathode electrode mounted in said growth chamber immersed in said solution in isolated relationship with one another and electrically connected to an external load; a plurality of isolated mesophyll cells suspended in said nutrient aqueous solution, said mesophyll cells producing malate when illuminated by sunlight, said nutrient solution being capable of sustaining the isolated mesophyll cells in an autotropic state and of initiating malate export from the illuminated mesophyll cells into the solution; a selected substance suspended in said nutrient solution to act on the malate to form NADH; and a potential mediator substance suspended in said nutrient solution to transfer electrons from said NADH to said anode.
Claim 2
Dependent Claim
140 words
A photosynthetically-driven biological fuel cell comprising: means forming a growth chamber having a transparent top exposed to sunlight; a nutrient aqueous solution contained in said growth chamber; an anode electrode and a cathode electrode mounted in said growth chamber immersed in said solution in isolated relationship with one another and electrically connected to an external load; a plurality of isolated mesophyll cells suspended in said nutrient aqueous solution, said mesophyll cells producing malate when illuminated by sunlight, said nutrient solution being capable of sustaining the isolated mesophyll cells in an autotropic state and of initiating malate export from the illuminated mesophyll cells into the solution; a selected substance suspended in said nutrient solution to act on the malate to form NADH; and a potential mediator substance suspended in said nutrient solution to transfer electrons from said NADH to said anode.
Claim 3
Dependent Claim
27 words
The biological fuel cell defined in claim 1, and which includes a catalyzing substance suspended in the nutrient solution for catalyzing the action of said potential mediator.
Claim 4
Dependent Claim
31 words
The biological fuel cell defined in claim 2, and which includes means creating an anaerobic region in the vicinity of said anode to protect the catalyzing step from energy-using oxygen consumption.
Claim 5
Dependent Claim
34 words
The biological fuel cell defined in claim 1, in which the isolated mesophyll cells are obtained from a substance selected from a class consisting of CAM plant species and C4 type photosynthetic plant species.
Claim 6
Dependent Claim
16 words
The biological fuel cell defined in claim 1, in which said selected substance is malic enzyme.
Claim 7
Dependent Claim
28 words
The biological fuel cell defined in claim 1, in which said potential mediator compound is selected from a class consisting of methylene blue, benzyl viologen and methyl viologen.
Claim 8
Dependent Claim
16 words
The biological fuel cell defined in claim 2, in which said catalyzing substance is xanthine oxidase.
Claim 9
Dependent Claim
31 words
The biological fuel cell defined in claim 3, in which said means creating an anaerobic region comprises a divider member porous to ions and solute molecules but impervious to mesophyll cells.
Claim 10
Dependent Claim
27 words
The fuel cell defined in claim 1, and which includes means in said nutrient solution to initiate malate export from the illuminated mesophyll cells to the solution.
Claim 11
Dependent Claim
25 words
The fuel cell defined in claim 9, in which said last-named means comprises pyruvic acid at approximately 5m molar (5 × 10 -3 m) concentration.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-25 | 1982-03-27 | 1982-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-25 | 1986-03-27 | 1986-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-25 | 1990-03-27 | 1990-09-26 | $7700.00 | Window Closed / Lapsed |