Micro-fuel cell power devices

Details Micro-fuel cell power devices Micro-fuel cell power devices

1998-12-10

2001-12-04

Kalafut, Stephen (Department: 1745)

Chemistry: electrical current producing apparatus, product, and

With pressure equalizing means for liquid immersion operation

C429S006000, C429S127000, C427S115000

Reexamination Certificate

active

06326097

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention relates generally to fuel cell devices, and more specifically to the manufacturing process for MICRO-FUEL CELL™ power devices and to their application configurations.
A number of miniature fuel cells suitable for use with portable electronic products are becoming available today, but less attention has been shown to the low-cost mass production and device packaging of these fuel cells for varied applications. There is limited information in the literature concerning such things as the coupling of these miniature cells to the various applications, methods for refueling the cells in a low-cost and efficient manner, or any type of thermal insulation to elevate the temperature of the cell for higher efficiency in various environmental conditions. Another problem with portable electronic appliances is that they need to be kept in a ready position that is secure but easily accessible when needed. For example, cellular phone holsters may use clips and gravity securing devices to keep the phone from dropping when jostled. Another problem with portable electronics is that they can easily be misplaced.
Representative prior inventions of this general type include U.S. Pat. Nos. 5,364,711 and 5,432,023, which describe miniature fuel cells that run on methanol and are used to run electronics, and U.S. Pat. Nos. 4,673,624 (“Fuel Cell”) and 5,631,099 (“Surface Replica Fuel Cell”), which describe methods of forming fuel cells. None of those patents describe how to package the fuel cell to efficiently run the electronics applications. U.S. Pat. No. 5,759,712 (“Surface Replica Fuel Cell for Micro Fuel Cell Electrical Power Pack”) describes how a fuel cell can be packaged in a general hybrid systems power pack which may be comprised of a fuel cell and other energy sources, such as a battery, flywheel, or solar cells. It mentions cellular phones in particular, but does not appear to describe the coupling configurations or refueling systems for these electrical applications. In this application, the porous gas manifolds and air gaps in the case of the power packs acts as both insulation and water control mechanism. None of those patents mentioned using exchangeable insulation to compensate for different environmental temperature conditions. However, none of those patents discloses or suggests the novel features of the present invention.
SUMMARY OF THE INVENTION
The present invention applies the fuel cells described in this inventor's U.S. Pat. Nos., 4,673,624, 5,631,099, and 5,759,712, to numerous electrical devices. Examples of devices that realize a significant advantage from such power systems include, but are not limited to, portable electronics and power tools; such as cellular phones, pagers, video camcorders, portable tools, portable PCs, portable toilets, smoke detectors, hearing aids, portable stereos, portable TVs, portable radios, night vision goggles, portable lighting, toys, computer peripherals, and portable vacuum cleaners.
The critical component in this invention is a fuel cell that is formed on a plastic sheet, including a number of fuel cells described in “Surface Replica Fuel Cell”, U.S. Pat. No. 5,631,099, U.S. Pat. No. 4,673,624, and U.S. Pat. No. 5,759,712. These fuel cells pack more energy in a smaller space than conventional rechargeable batteries by utilizing liquid methanol and water fuel. The methanol fuel has effectively 5 to 13 Whr per cubic inch (20% to 50% efficiency) energy density. This is 3 to 9 times the energy density of today's best nickel cadmium batteries, and 40 to 120 times that of standard cellular phone battery packs. These micro-fuel cells are lighter than conventional rechargeable batteries. The methanol fuel has effectively 1200 to 3000 Whr per kg energy per unit mass (20% to 50% efficiency). This is 2 to 5 times the 600 Whr per kg quoted for the latest rechargeable lithium ion batteries (Science News, Mar. 25, 1995).
Our first micro-fuel cell is designed to replace the standard cellular phone battery packs. Conventional cell phones usually have a warning alert signal when the battery is low, but the accuracy and dependability of these indicators often leave much room for improvement. Determining the remaining energy capacity from a rechargeable battery typically uses the voltage output level as an indicator of charge but does not measure the capacity. Therefore, history of the discharge is used to assess the future of the remaining output. This electronic assessment of remaining energy capacity is complex, requires diagnostic electronics and is prone to errors. The liquid fueled fuel cell eliminates this uncertainty. Checking the fuel supply is as simple as looking at the liquid level in the fuel tank. The amount of fuel remaining compared to the total fuel tank capacity is the fraction of the total energy. Refueling also provides instant recovery. Components of these micro-fuel cells are inexpensive. Manufacturing and assembly cost are low. The production techniques allow the fuel-cells and power supply systems to be manufactured at costs similar to rechargeable batteries. The production techniques enable the fuel cells to be produced in a roll-to-roll manufacturing method, similar to printing press processes. The production is envisioned as taking place in a vacuum system in which the metal electrodes and catalysts are deposited onto a reeled plastic web. The electrolytes may also be deposited by means of a reeled vacuum deposition system or dip tank. The individual fuel cell devices would be cut off the rolls of fuel cells and assembled. The edge seals are expected to be heat seals, with the cutting operation and heat seal operation envisioned as one and the same. The MICRO-FUEL CELL is the “green” (environmentally clean) solution to energy needs. It is never thrown away, but rather refueled with common ethanol or methanol, an abundant and renewable energy source. The production process and the disposal of manufacturing by-products do not present toxic waste problems. The plastic fuel tanks when empty can be disposed of as common food packaging.
One aspect of this invention addresses the fact that small portable fuel cells encounter a range of exterior environmental temperature and humidity. To compensate for this range and to optimize the performance of the fuel cells an adjustable moisture and thermal internal insulation barrier is used to allow fuel cells to run at elevated temperatures.
Current appliances that run on rechargeable batteries are recharged by “plugging in” to alternating current sources or DC electrical systems, such as found in a car or other vehicle. This source of energy may be inconvenient or unavailable for many users in remote locations. The present invention allows the fuel cell energy system of an appliance, the fuel cell itself, and the fuel supply packaging to all fit together in a convenient manner.
These and further and other objects and features of the invention are apparent in the disclosure, which includes the above and ongoing written specification, with the claims and the drawings.


REFERENCES:
patent: 4138510 (1979-02-01), Koziol et al.
patent: 4243508 (1981-01-01), Dankese
patent: 4252868 (1981-02-01), Bohm et al.
patent: 4294891 (1981-10-01), Yao et al.
patent: 4421579 (1983-12-01), Covitch et al.
patent: 4623415 (1986-11-01), Kahara et al.
patent: 4661423 (1987-04-01), Ueno et al.
patent: 4666579 (1987-05-01), Beaver et al.
patent: 4673624 (1987-06-01), Hockaday
patent: 4769297 (1988-09-01), Reiser et al.
patent: 4793910 (1988-12-01), Smotkin et al.
patent: 4804449 (1989-02-01), Sweeney
patent: 4818637 (1989-04-01), Molter et al.
patent: 4824741 (1989-04-01), Kunz
patent: 4826554 (1989-05-01), McIntyre
patent: 4865925 (1989-09-01), Ludwig et al.
patent: 4931168 (1990-06-01), Watanabe et al.
patent: 5084144 (1992-01-01), Reddy et al.
patent: 5108849 (1992-04-01), Watkins et al.
patent: 5173166 (1992-12-01), Tomantschger et al.
patent: 5187025 (1993-02-01), Kelland et al.
patent: 5234777 (1993-08-01), Wilson
patent: 5240786 (1993-08-01), Ong et al.
pa

Affiliated with

Also associated with

Rating

Micro-fuel cell power devices does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Micro-fuel cell power devices, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Micro-fuel cell power devices will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2590347