The embodiment discussed herein is directed to a cartridge for fuel cell and a fuel cell.
The recent portable information apparatuses are further increasingly downsized and lightened and have the speed and achievements, etc. improved as the semiconductor technique and the communication technique are developed. Accompanying this, the cells which are the electric sources of the portable information apparatuses are also downsized and lightened and has the capacity increased.
The recent most general drive electric source of the portable information apparatuses is lithium ion cell. The lithium ion cell realized high drive voltages and cell capacities at the time when the lithium ion cell was put to practical uses, and has had the achievements improved as the portable information apparatuses have been developed.
However, the lithium ion cell is limited in improving the achievements and cannot always sufficiently satisfy further requirements as the drive electric source of the portable information apparatuses.
Under such circumstances, as a new energy device taking over the lithium ion cell, fuel cells are noted. In the fuel cell, a fuel is supplied to the cathode to produce electrons and protons, and the produced protons are reacted with oxygen supplied to the anode to thereby generate power.
A fuel of the fuel cell, specifically methanol is stored in a cartridge for fuel cell disposed separate from the power generation part. For the fuel cell to continuously generate power, it is necessary to continuously supply a fuel stored in the cartridge for fuel cell to the power generation part.
As a technique for supplying a fuel stored in the cartridge for fuel cell to the power generation part, the technique for supplying a fuel vaporized in the cartridge for fuel cell to the power generation part is proposed.
According to an aspect of the embodiment, a cartridge for fuel cell for supplying a fuel to a fuel cell, the cartridge for fuel cell comprising: a cartridge case having a plurality of holes formed at least in one side; a fuel vaporization stabilization layer formed on the side with said plurality of holes formed in inside the cartridge case; and a fuel impregnation material sealed inside the cartridge case.
According to an aspect of the embodiment, a fuel cell comprising a power generation part including a fuel electrode, a solid electrolytic layer and an air electrode, and a slot provided in the power generation part on the side of the fuel electrode, for removably receiving a cartridge for fuel cell which discharges vaporized fuel, the cartridge for fuel cell comprising a cartridge case having a plurality of holes formed in one side, a fuel vaporization stabilization layer formed on the side with said plurality of holes formed in inside the cartridge case, and a fuel impregnation material sealed inside the cartridge case.
Additional objects and advantages of the embodiment will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the embodiment. The object and advantages of the embodiment will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
As described previously, as a technique for supplying a fuel stored in the cartridge for fuel cell to the power generation part, the technique for supplying a fuel vaporized in the cartridge for fuel cell to the power generation part is proposed. However, in the proposed technique, as a fuel in the cartridge for fuel cell is consumed, the fuel is discharged gradually in smaller quantities. Accordingly, it is difficult to maintain stable electric power by the proposed technique.
In the state illustrated in
As described above, when the fuel is penetrated in the simple fuel impregnation material 136, specifically, the fuel impregnation material 136 of a polymer material of a strong skeleton, the concentration of the fuel in the part 140 located near the holes 34 become very much lower, which makes it difficult to stably discharge the vaporized fuel.
The inventors of the present application made earnest studies and have got the idea that a fuel vaporization stabilization layer of a porous material is formed between the side with the holes formed in and the fuel impregnation material, whereby the vaporized fuel can be stably discharged. A fuel impregnation material which is able to sufficiently increase the volume when impregnated with the fuel than when not impregnated with the fuel is used, whereby the vaporized fuel can be more stably discharged.
Preferred embodiment will be explained with reference to accompanying drawings.
As illustrated in
In
As illustrated in
As described above, according to the present embodiment, the fuel vaporization stabilization layer 38 of a porous material is provided between a plurality of the holes 34 formed in at least one side of the cartridge case 32 and the fuel impregnation material 36, whereby the fuel vaporization stabilization layer 38 can prevent the plural holes 34 from being closed by the fuel impregnation material 36. Thus, according to the present embodiment, the cartridge for fuel cell which can stably discharge the fuel can be provided.
According to the present embodiment, the fuel vaporization stabilization layer 38 is formed, whereby even when the fuel impregnation material 36 is formed of a polymer material of a strong skeleton, the fuel is consumed uniformly in the direction of the thickness of the cartridge case 32. Thus, according to the present embodiment, even when the fuel impregnation material 36 of a polymer material of a strong skeleton is used, the paths for the fuel discharge in the fuel impregnation material 36 can be prevented from becoming extremely long, and the fuel can be stably provided.
According to the present embodiment, the fuel impregnation material 36 is formed of a material which is able to increase the volume when impregnated with a large amount of the fuel in comparison with a volume at the time when not impregnated with the fuel, whereby the volume of the fuel impregnation material 36 sufficiently decreases as the content of the fuel decreases. Thus, according to the present embodiment, even when the fuel penetrated in the fuel impregnation material 36 is consumed and decreased, the fuel penetrated in the fuel impregnation material 36 is retained in a high concentration. According to the present embodiment, the cartridge for fuel cell which can stably supply the vaporized fuel can be provided.
The cartridge for fuel cell and the fuel cell according to one embodiment will be explained with reference to
As illustrated in
In the fuel electrode-side housing 28, a slot 29 for receiving the cartridge for fuel cell 30 is formed. In the slot 29, the cartridge for fuel cell 30 is inserted. The cartridge for fuel cell 30 is removable from the slot 29.
It is necessary that the air electrode collector layer 12 is conductive and highly anticorrosive. To this end, the air electrode collector layer 12 is formed of, e.g., Au-plated stainless (SUS304, SUS316 or others), etc. It is necessary that the air electrode collector layer 12 introduces oxygen in the air into the air electrode catalytic layer 16. To this end, the air electrode collector layer 12 has a structure of mesh, expanded metal, foam or others.
It is necessary that the air electrode gas diffusion layer 14 introduces oxygen in the air into the air poly catalytic layer 16. It is necessary that the air electrode gas diffusion layer 14 also ensures the conduction between the air electrode catalytic layer 16 and the air electrode collector layer 12. To this end, the air electrode gas diffusion layer 14 is formed of, e.g., a porous conductor film, e.g., carbon paper or others. As the carbon paper, carbon paper by, e.g., Toray Industries, Inc. can be used.
The air electrode catalytic layer 16 is formed of a material which is able to generate the electrochemical reaction for producing water from protons (H+) and oxygen (O2). Specifically, the air electrode catalytic layer 16 is formed by mixing a catalyst or a catalyst carrier, and a proton conductive polymer solid electrolyte and applying the mixture to the air electrode gas diffusion layer 14 or the solid electrolytic layer 18. As the air catalytic layer 16, TEC10E50E, which is a platinum carrying catalyst, by Tanaka Kikinzoku Kogyo K.K., for example, can be used.
The solid electrolytic layer 18 is a path for transferring protons generated on the fuel electrode-side to the air electrode-side and is formed of an ion conductor which is not electron conductive. The solid electrolytic layer 18 can be formed of, e.g., perfluorosulfonic acid-based polymer or others can be used. As such perfluorosulfonic acid-based polymer, Nafion (registered trademark), for example, by E.I.du Pont de Nemours and Company can be used. More specifically, as the solid electrolytic layer 18, Nafion N112 can be used.
The fuel electrode catalytic layer 20 is formed by applying, particles of platinum or others, carbon powder and a polymer forming the electrolytic layer to the fuel electrode gas diffusion layer or the solid electrolytic layer. Particles to be applied, for example, to the porous conductor film is not essentially of platinum or others and can be of an alloy of platinum and a transition metal, such as ruthenium or others. As the fuel electrode catalytic layer 20, TEC61E54, for example, which is a platinum-ruthenium alloy carrying catalyst by Tanaka Kikinzoku Kogyo K.K.
It is necessary that the fuel electrode gas diffusion layer 22 introduces the vaporized fuel into the fuel electrode catalytic layer 20. It is necessary that electrical conduction is ensured between the fuel electrode catalytic layer 20 and the fuel electrode collector layer 24. To this end, the fuel electrode gas diffusion layer 22 is formed of a porous conductor film of, e.g., carbon paper or others. As such carbon paper, the carbon paper by, e.g., Toray Industries, Inc. can be used.
It is necessary that the fuel electrode collector layer 24 is conductive and highly anticorrosive. To this end, the fuel electrode collector layer 24 is formed of, e.g., Au plated stainless (SUS304, SUS316 or others), etc. It is necessary that the fuel electrode collector layer 24 introduces the vaporized gas into the fuel electrode catalytic layer 20. To this end, the fuel electrode collector layer 24 has the structure of mesh, expanded metal, foam or others.
The vaporized fuel diffusion layer 26 is for diffusing the vaporized fuel discharged from the cartridge for fuel cell 30. The upper end part of the vaporized fuel diffusion layer 26 is exposed outside out of the housings 10, 28 of the fuel cell system 2. The upper end part exposed out of the housings 10, 28 functions as a carbon dioxide outlet for exhausting the carbon dioxide.
As illustrated in
As the porous material forming the fuel vaporization stabilization layer 38, a material which is stable to the aqueous solution of a high concentration of methanol is used. As such material, a porous fluoroplastic material, such as PTFE (Poly Tetra Fluoro Ethylene), PVDF (PolyVinylidene DiFluorie) or others, can be used. The fuel vaporization stabilization layer 38 may be formed of fluoroplastic fiber. The fuel vaporization stabilization layer 38 may be formed of unwoven fabric of carbon fiber, or others.
The size of the fuel impregnation material 36 which is not impregnated with the fuel is set, e.g., at about 20 volume % of the storage capacity of the cartridge case 32. The fuel impregnation material 36 of such size can be prepare by cutting the fuel impregnation material 36 of a large size into a required size. The fuel impregnation material 36 is formed of a polymer material whose volume increases as the material is increasingly impregnated with the fuel. As the polymer material whose volume increases as the fuel more penetrates, a polymer material of a flexible skeleton is used.
As such fuel impregnation material 36, the fuel impregnation material 36 impregnated with the fuel increases the volume by 50% or above of a volume thereof when the fuel impregnation material 36 is not impregnated with the fuel. That is to say, the fuel impregnation material 36 impregnated with the fuel increases the volume by 50% or above of a volume of the fuel impregnation material 36 not impregnated with the fuel. In this specification and the claims, the volume of the fuel impregnation material 36 at the time when impregnated with the fuel does not mean a volume of the fuel impregnation material 36 simply impregnated with the fuel but a volume of the fuel impregnation material 36 sufficiently impregnated with the fuel. More specifically, the volume of the fuel impregnation material 36 impregnated with the fuel means a volume of the fuel impregnation material 36 in the state where the fuel impregnation material 36 is impregnated with the fuel substantially to the maximum.
The fuel impregnation material 36 can be formed of, e.g., a polymer material containing carboxyl groups or sulfone groups can be used. It is necessary that the fuel impregnation material 36 is not dissolvable to the methanol aqueous solution of high concentration. In view of this, as the fuel impregnation material 36, a perfluoro-based polymer material containing carboxyl groups or sulfone groups is especially preferable. As such material, specifically, Nafion (registered trademark), for example, by E.I.du Pont de Nemours and Company can be used. As such nafion film, Nafion N117 (product name), for example, can be used. The fuel impregnation material 36 is not essentially the nafion film by E.I.du Pont de Nemours and Company. For example, Flemion (registered trademark) by Asahi Glass Co., Ltd. may be used as the fuel impregnation material 36. Aciplex (registered trademark), for example, by Asahi Kasei Corporation may be used as the fuel impregnation material 36.
As the fuel the fuel impregnation material 36 is impregnated with, a methanol aqueous solution of a methanol concentration of 80 volume % or above. The fuel of such relatively high methanol concentration is used so that the fuel can be discharged in a high concentration.
As illustrated in
Then, the fuel 40 penetrates into the inside space of the cartridge case 32 through the holes 34 formed in one side 32a of the cartridge case 32 of the cartridge for fuel cell 30. The fuel which has penetrated in the space inside the cartridge case 32 penetrates in the fuel impregnation material 36. As the fuel impregnation material 36 is impregnated with the fuel, it increases the volume and has the state illustrated in
Next, the application of the fuel cell according to the present embodiment to a portable telephone will be explained by means of an example.
The fuel cell part 48 corresponds to the fuel cell system 2 illustrated in
As illustrated in
The fuel cell part 48 may be removably mounted on the portable telephone, as is the cradle of the portable telephone or maybe fixed to the back of the portable telephone body.
When power is generated in the fuel cell part 48, the power is charged into the storage cell, such as a lithium cell or others, disposed in the portable telephone 56.
(Evaluation Result)
Then, the result of evaluating the cartridge for fuel cell according to the present embodiment will be explained with reference to
As seen in
As described above, according to the present embodiment, the fuel impregnation material 36 whose volume sufficiently increases when much impregnated with the fuel than a volume at the time when not impregnated with the fuel is used, whereby as the content of the fuel decreases, the volume of the fuel impregnated material 36 sufficiently decreases. Resultantly, the concentration of the fuel penetrated in the fuel impregnation material 36 is retained in a relatively high concentration. Thus, according to the present embodiment, the cartridge for fuel cell which can stably supply the vaporized fuel can be provided.
(Modifications)
Next, a modification of the cartridge for fuel cell according to the present embodiment will be explained with reference to
The cartridge for fuel cell 30a according to the present modification is characterized mainly in that an opening 50 is formed for pouring the fuel into the cartridge case 32.
As illustrated in
In the cartridge for fuel cell 30a according to the present modification, with the forward end part 54 of a fuel feeder 52 inserted in the opening 50 of the cartridge case 32, the fuel 40 is poured into the cartridge case 32.
While the fuel 40 is pouring into the cartridge case 32, preferably, a tight closure sheet 51 is adhered to one side 32a of the cartridge case 32 so that the vaporized fuel is not discharged through the holes 34 formed in one side 32a of the cartridge case 32.
As described above, it is possible that the opening 50 which arrives at the inside of the cartridge case 32 is formed, and the fuel is poured through the opening 50.
All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiment of the present invention has been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
This application is a Continuation of International Application No. PCT/JP2006/306017, with an international filing date of Mar. 24, 2006, which designating the United States of America, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
Parent | PCT/JP2006/306017 | Mar 2006 | US |
Child | 12236151 | US |