TECHNICAL FIELD

The present invention relates to an electric automobile on which a hydrogen generating device for supplying hydrogen to a fuel cell is loaded. Recently, measures for problems of environment and natural resources have become important, and development of an electric automobile is actively pursued as one of those measures. Among them, in connection with the electric automobile provided with a fuel cell as a power source to obtain its driving force, those having hydrogen, which is a fuel for generation using this fuel cell or a raw fuel for generating hydrogen loaded are under development in various forms. In the electric automobile with hydrogen loaded, hydrogen is loaded as being filled in a cylinder as a compressed gas or in a method that hydrogen is stored in a hydrogen storage alloy (See Patent Documents 1 to 3, for example). In this type of electric automobile with hydrogen loaded, since the fuel gas to be supplied to an electrode of the fuel cell is a hydrogen gas with an extremely high purity, high generation efficiency can be obtained at driving the fuel cell, and the size of the fuel cell can be reduced. Also, since the hydrogen gas with an extremely high purity is used, harmful substances are not generated in a process that various reactions progress in the electric automobile, and it has a merit that the environment is not polluted by driving of the electric automobile.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2002-370544
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2003-182379
[Patent Document 3] Japanese Unexamined Patent Application Publication No. 2004-22364

On the other hand, as an electric automobile with a raw fuel for generating hydrogen loaded, those having methanol or the like loaded as the raw fuel and moreover a reformer which reforms this raw fuel and performs reforming reaction for generating a gas including hydrogen is known (See Patent Documents 4 to 7, for example). For this type of electric automobile having the raw fuel and the reformer loaded in this way, when it particularly uses liquid fuel such as methanol as a raw fuel, it has a merit that a distance which can be covered by the electric automobile by one fuel replenishment is longer than the case where a gas fuel is loaded. Moreover, the raw fuel such as methanol and hydrocarbon has a merit that handling at transportation and the like is easy and safe as compared with hydrogen gas.
[Patent Document 4] Japanese Unexamined Patent Application Publication No. 2000-149974
[Patent Document 5] Japanese Unexamined Patent Application Publication No. 2001-113960
[Patent Document 6] Japanese Unexamined Patent Application Publication No. 2001-202980
[Patent Document 7] Japanese Unexamined Patent Application Publication No. 2001-298807

However, with regard to the electric automobile having hydrogen loaded as a fuel has such a problem pointed out in spread of electric automobile that it is difficult to widely distribute hydrogen to be filled in a cylinder or stored in the hydrogen storage alloy and to make them available easily. Particularly, handling of hydrogen gas is not easy, and there are many problems to be solved in easy transportation and storage of a large quantity of hydrogen gas. If a hydrogen storage alloy is used for transportation or storage of hydrogen, handling is facilitated, but currently known hydrogen storage alloys are all rare metal and extremely expensive. Therefore a method that all the means for transportation and storage of hydrogen are constituted using a hydrogen storage alloy can be hardly realized. In transportation or storage of hydrogen in whatever method, it has a problem that a stable hydrogen distribution system should be established in order to directly supply hydrogen to an electric automobile as a fuel.

Moreover, with regard to a reformer when methanol, dimethyl ether (DME), ethanol, natural gas, propane, gasoline, etc. is loaded on an electric automobile as a raw fuel, development of a methanol reformer with the lowest reforming temperature among them is the most advanced, and there are three reforming methods are currently employed: steam reforming, partial oxidization reforming and reforming using the both (See Non-patent Document 1). However, with any of the reforming method being employed, reforming should be performed at a high temperature of 200 deg. C or above in order to manufacture a gas including hydrogen, and there are problems of poisoning of reforming catalyst, removal of CO contained in the reformed gas (gas including hydrogen), mixture of nitrogen in the air into the reformed gas obtained by partial oxidization reform or reform using the both methods.
[Non-patent Document 1] " Development and Practical Application of Solid Polymer type Fuel Cell", PP 141 to 166, May 28, 1999, issued by Technical Information Institute, Co., Ltd.

Moreover, an invention of a method for generating hydrogen by electrochemical reaction (See Patent Documents 8, 10) and an invention of a fuel cell using hydrogen generated by an electrochemical method (See Patent Documents 9 to 11) are also known.
[Patent Document 8] Japanese Patent Publication No. 3328993
[Patent Document 9] Japanese Patent Publication No. 3360349
[Patent Document 10] United States Patents Publications Nos. 6,299,744 , 6,368,492 , 6,432,284 , 6,533,919 , and United States Patent Publication No. 2003/0226763
[Patent Document 11] Japanese Unexamined Patent Application Publication No 2001-297779

Patent Document 8 cited above describes (Claim 1), "a method for generating hydrogen comprising providing a pair of electrodes on the two opposite surfaces of a cation exchange membrane, contacting a fuel containing at least methanol and water with one electrode having a catalyst, applying a voltage between the pair of electrodes so that electrons are withdrawn from the electrodes thereby causing a reaction to occur on the electrodes whereby hydrogen ions are generated from methanol and water, and allowing hydrogen ions to be converted on the other electrode, being supplied with electrons, into hydrogen molecules." The same patent document discloses another method (paragraphs [0033] to [0038]) for selectively generating hydrogen using a conversion system, the method comprising supplying water or water vapor together with methanol which serves as a fuel, applying a voltage via an external circuit to cause electrons to be withdrawn from a fuel electrode, so that reaction represented by CH3OH + 2H2O CO2 + 6e<-> + 6H<+> occurs on the fuel electrode, and allowing hydrogen ions thus produced to pass through a cationic exchange membrane to reach the opposite electrode where the hydrogen ions undergo reaction represented by 6H<+> + 6e<-> 3H2. Patent Document 9 cited above describes (paragraphs [0052] to [0056]) a fuel cell which utilizes hydrogen generated by a method as described above.

According to the inventions described in Patent document 8 (paragraph [0042]) and Patent Document 9 (paragraph [0080]) cited above, it is possible to generate hydrogen at a low temperature. However, the methods described in those inventions are obviously different from the hydrogen generating device to be loaded on an electric automobile of the present invention which will be given below in following points: those methods require the application of voltage, and hydrogen is generated on the electrode opposite to the electrode (fuel electrode) to which fuel is supplied, and no oxidizing agent is supplied to the opposite electrode.

This holds true also for the inventions disclosed by Patent Document 10 cited above similarly to Patent Documents 8 and 9 cited above. Those inventions use a system for generating hydrogen where protons generated on anode 112 serving as fuel electrode pass through partition membrane 110 to reach cathode 114 opposite to the anode, and according to the system, voltage from DC power source 120 is provided between anode (fuel electrode) and cathode (opposite electrode) to decompose organic fuel such as methanol or the like electrochemically. In addition, hydrogen is generated on the electrode opposite to the fuel electrode, and no oxidizing agent is supplied to the opposite electrode.

Patent Document 11 cited above discloses a fuel cell system incorporating a hydrogen generating device. According to the disclosure (Claim 1) of the invention, "Liquid fuel containing alcohol and water is supplied to porous electrode 1 (fuel electrode), air is supplied to gas diffusion electrode 2 (oxidizing agent-applied electrode) opposite to electrode 1, and a load is inserted between a terminal leading to porous electrode 1 and another terminal leading to gas diffusion electrode 2 to achieve electric connection allowing a positive voltage to be applied to porous electrode 1 via the load from gas diffusion electrode 2 which corresponds to the positive electrode of MEA2 capable of acting as a conventional fuel cell." The same patent document further adds (paragraph [0007]), "As a result, alcohol reacts with water to produce carbon dioxide gas and hydrogen ion, the hydrogen ion passes through an electrolyte membrane 5 to reach a gas diffusion electrode 6 located centrally where the hydrogen ion is converted into hydrogen gas. On the opposite surface of gas diffusion electrode 6 in contact with another electrolyte layer 7, there arises another electrode reaction where hydrogen gas is reconverted into hydrogen ion, and hydrogen ions migrate through electrolyte layer 7 to reach another gas diffusion electrode 2 where hydrogen ions react with oxygen in air to produce water." Thus, with this system, electric energy generated by a fuel cell is utilized to generate hydrogen on the hydrogen generating electrode (gas diffusion electrode 6) which is then supplied to the fuel cell. Moreover, the system is the same with those described in the patent documents cited above in that hydrogen is generated on the electrode opposite to the fuel electrode.

There are some other known methods for generating hydrogen (See Patent Documents 12 and 13). According to the inventions, a reaction system with a partition membrane is used where anode (electrode A) and cathode (electrode B) are placed opposite to each other with a proton conducting membrane (ion conductor) inserted there between, and where alcohol (methanol) is oxidized with or without concomitant application of voltage, or with concomitant uptake of electric energy. All those methods, however, are based on a method whereby alcohol is oxidized by means of an electrochemical cell (the reaction product includes carbonic diester, formalin, methyl formate, dimethoxymethane, etc.), and not on a method whereby alcohol is converted by reduction into hydrogen."
[Patent Document 12] Japanese Unexamined Patent Application Publications No. 6-73582 (Claims 1 to 3, paragraph [0050])
[Patent Document 13] Japanese Unexamined Patent Application Publications No. 6-73583 (Claims 1 and 8, paragraphs [0006] and [0019])

DISCLOSURE OF THE INVENTION

With a view to give a solution to the above problems, the present invention aims to provide an electric automobile on which hydrogen generating device is loaded which can easily supply hydrogen to a fuel cell and can generate a gas containing hydrogen at a low temperature. But the problems of car efficiency is remind in all inventions described here.

Number of patents gave different innovative solutions how to convert car kinetic energy in the cases of car decelerations and braking. All known solutions of energy recuperation using regenerative breaking system based on the car electric motor (s) as electric generator connected to the car battery. The problem is that electric motors are optimized to power car and not optimized as electric generators. The main aim of presented inventions is to develop a mechanical upgrade of the regenerative braking system that allows significantly increasing op power generating by motors operating as generators.  The patent abstract see below.