| Thermally efficient hydrogen storage system -> Monitor Keywords |
|
|
 
Thermally efficient hydrogen storage systemRelated Patent Categories: Chemistry: Electrical Current Producing Apparatus, Product, And Process, Fuel Cell, Subcombination Thereof Or Methods Of Operating, Having Means For Active Material Generation Or Regeneration, By Heating Or CoolingThermally efficient hydrogen storage system description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20060188762, Thermally efficient hydrogen storage system. Brief Patent Description - Full Patent Description - Patent Application Claims
FIELD OF THE INVENTION [0001] The disclosed methods and apparatus relate to the field of hydrogen storage systems. In particular, the methods and apparatus relate to hydrogen storage using both endothermic and exothermic hydrogen generators. BACKGROUND OF THE INVENTION [0002] Fuel cells that generate electrical power using reactions between hydrogen and an oxidizing gas such as oxygen or air are well known in the art. Such fuel cells require a source of hydrogen, such as a compressed hydrogen gas cylinder, a liquefied hydrogen tank, a hydrogen storage powder, a hydrogen storage alloy, a hydride such as lithium or sodium borohydride, a metal hydride or a reformed hydrocarbon such as natural gas or methane. The typical fuel cell has a single source of hydrogen, which may be produced by either exothermic or endothermic processes. [0003] Depending on their efficiency, present fuel cells may generate more waste heat than usable electrical energy. For applications where fuel cells are used to power small, portable electronic devices such as cell phones, laptop computers, video cameras, flashlights, portable electrical tools, personal digital assistants, etc. the production of large amounts of waste heat can create problems with overheating of the electronic device or with excessively hot hand-held devices. As many electronic devices generate waste heat by their operation, the incorporation of a hydrogen fuel cell that produces additional waste heat creates serious problems with thermal control. BRIEF DESCRIPTION OF THE DRAWINGS [0004] The following drawings form part of the present specification and are included to further demonstrate certain embodiments of the invention. The embodiments may be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments of the invention presented herein. [0005] FIG. 1 illustrates an exemplary apparatus (not to scale) comprising exothermic and endothermic hydrogen generators. [0006] FIG. 2 illustrates another exemplary apparatus (not to scale) comprising exothermic and endothermic hydrogen generators, a fuel cell and a portable electronic device. DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS DEFINITIONS [0007] As used herein, "a" or "an" may mean one or more than one of an item. [0008] The terms "exothermic" and "endothermic" are used according to their plain and ordinary meanings. Generally, an "exothermic" process or reaction is one that releases heat to its environment, while an "endothermic" process or reaction is one that absorbs heat from its environment. Within the context of the present disclosure, an exothermic hydrogen generator will transfer heat to an endothermic hydrogen generator, while an endothermic hydrogen generator will absorb heat from an exothermic hydrogen generator during hydrogen generation. In certain embodiments of the invention, an endothermic hydrogen generator may also absorb heat from other sources, such as a fuel cell. [0009] As used herein, the term "about" when applied to a number means within plus or minus five percent of that number. For example, "about 100" means any number between 95 and 105. [0010] As used herein, the term "approximately" means within ten percent of a value. For example, "approximately equal" would mean that a first value is within plus or minus ten percent of a second value. [0011] As used herein, an "electronic device" comprises any device and/or apparatus that may derive part or all of its power supply from a hydrogen based fuel cell. A "portable electronic device" is one that may be moved from one location to another by a person. In some embodiments of the invention, a "portable electronic device" may be carried by a person. In certain embodiments of the invention, a "portable electronic device" may be a hand-held device. "Portable electronic devices" include, but are not limited to, cell phones, laptop computers, video cameras, flashlights, portable electrical tools and personal digital assistants. [0012] As used herein, two or more components are "operably coupled" when there are one or more connections between the components that allow or facilitate their functional interaction. For example, a hydrogen generator would be "operably coupled" to a fuel cell when there is a functional attachment that allows hydrogen from the hydrogen generator to be used by the fuel cell to generate electrical power. Similarly, a fuel cell would be "operably coupled" to an electronic device when there is a functional attachment that allows electrical power generated by the fuel cell to be used to power the electronic device. Fuel Cells [0013] Certain embodiments of the invention concern fuel cells comprising both endothermic and exothermic hydrogen generators. The principles underlying hydrogen based fuel cells have been known since the experiments of William Grove in 1839. A variety of hydrogen utilizing fuel cell designs are known in the art, including but not limited to the polymer electrolyte membrane (PEM) fuel cell, the phosphoric acid fuel cell, the molten carbonate fuel cell and the solid oxide fuel cell. The methods and apparatus disclosed herein are not limited as to the type of fuel cell, so long as the fuel cell utilizes hydrogen. Different fuel cells are designed to function at different operating temperatures. In some embodiments of the invention, fuel cells designed to operate at near ambient temperatures, such as PEM fuel cells, may be used in the disclosed methods and apparatus. [0014] The electrochemical reactions underlying hydrogen fuel cells are known. Once hydrogen is produced, it is provided to the anode side of the fuel cell, where it encounters a catalyst, such as platinum. The catalyst facilitates the removal of electrons from hydrogen, creating H.sup.+ ions. The electrons travel through an external circuit to the cathode side of the fuel cell, providing electrical power. At the cathode, H.sup.+, electrons and oxygen react to create water. Waste heat is also produced as a byproduct of the electrochemical processes. [0015] Variations on this basic scheme are well known. The charge carrier species in PEM fuel cells and phosphoric acid fuel cells is H.sup.+, which diffuses from the anode to the cathode through an electrolyte. Carbonate fuel cells involve an intermediary process, in which oxygen reacts with electrons and carbon dioxide at the cathode to produce CO.sub.3.sup.-2. The CO.sub.3.sup.-2 passes through an electrolyte to the anode, where it reacts with hydrogen to form water and carbon dioxide, releasing two electrons. In solid oxide fuel cells, another intermediary process results in the cathodic formation of O.sup.-2, which reacts with hydrogen at the anode to form water and release electrons. These and any other known type of hydrogen utilizing fuel cells are all contemplated for use in the methods and apparatus disclosed herein. [0016] The voltage difference generated by a single fuel cell is limited to about 1.2 volts per electrode pair (anode plus cathode). It is contemplated that the apparatus and methods disclosed herein may utilize single fuel cells or multiple fuel cells that are connected in series to provide any level of voltage required to operate an associated electronic device. Hydrogen Generators [0017] Various embodiments of the invention comprise both exothermic and endothermic hydrogen generators. The claimed methods and apparatus are not limiting as to the particular exothermic or endothermic hydrogen generators used. Rather, it is contemplated that any exothermic hydrogen generator known in the art could be used with any known endothermic hydrogen generator. Continue reading about Thermally efficient hydrogen storage system... Full patent description for Thermally efficient hydrogen storage system Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Thermally efficient hydrogen storage system patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Thermally efficient hydrogen storage system or other areas of interest. ### Previous Patent Application: Fuel cell power plants Next Patent Application: Fuel cell system comprising modular design features Industry Class: Chemistry: electrical current producing apparatus, product, and process ### FreshPatents.com Support Thank you for viewing the Thermally efficient hydrogen storage system patent info. IP-related news and info Results in 0.33509 seconds Other interesting Feshpatents.com categories: Software: Finance , AI , Databases , Development , Document , Navigation , Error 174 |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
