Hydrogen storing container and hydrogen storing alloy charging method

Abstract

To uniform a temperature distribution of a hydrogen storing alloy in an inner portion of a container to cause a hydrogen storing and discharging reaction to efficiently proceed.SOLUTION: A hydrogen storing container includes: a tubular container body 10 which has a housing chamber 30 which houses a hydrogen storing alloy; and a plurality of pipes 40 which extend along an axial direction of the container body 10 in an inner portion of the housing chamber 30 and through which a heat medium for heating and cooling the hydrogen storing alloy flows. The container body 10 is disposed so as to have the axial direction along a horizontal direction. When the housing chamber 30 is equally divided in an upper and lower direction in two, a first region 30A as an upper region and a second region 30B as a lower region, the number of the pipes 40 disposed in the second region 30B is larger than the number of the pipes 40 disposed in the first region 30A.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a hydrogen storage container and a method for charging a hydrogen storage alloy.

Background Art

[0002] In recent years, as a method for safely and storing hydrogen in a large capacity, a hydrogen storage container containing a hydrogen storage alloy has attracted attention. In this storage method, hydrogen is stored in the hydrogen storage container by causing the hydrogen storage alloy to absorb hydrogen, and hydrogen is filled from the hydrogen storage container into another fuel tank or the like by releasing hydrogen from the hydrogen storage alloy.

[0003] When the hydrogen storage alloy absorbs hydrogen, it is an exothermic reaction, and when hydrogen is released from the hydrogen storage alloy, it is an endothermic reaction. Therefore, in order to promote these reactions, it is necessary to heat or cool the hydrogen storage alloy. Patent Document 1 discloses a hydrogen storage container in which a large number of plate fins are provided inside the container. By providing a large number of plate fins, the hydrogen storage alloy can be efficiently heated and cooled.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a hydrogen storage container using a hydrogen storage alloy, increasing the hydrogen absorption amount and the hydrogen release amount is an important issue. In order to increase the hydrogen absorption amount and the hydrogen release amount, it is important to make the temperature distribution of the hydrogen storage alloy inside the container uniform and to efficiently advance the hydrogen absorption / release reaction.

Means for Solving the Problems

[0006] A hydrogen storage container according to one aspect of the present invention includes a cylindrical container body having a storage chamber for storing a hydrogen storage alloy, and a plurality of pipes extending along the axial direction of the container body inside the storage chamber through which a heat medium for heating and cooling the hydrogen storage alloy flows. The container body is arranged such that the axial direction is along the horizontal direction, and when the storage chamber is bisected in the vertical direction and the upper region is defined as the first region and the lower region is defined as the second region, the number of pipes arranged in the second region is larger than the number of pipes arranged in the first region.

[0007] A hydrogen storage container according to another aspect of the present invention includes a cylindrical container body having a storage chamber for storing a hydrogen storage alloy, a plurality of pipes extending along the axial direction of the container body inside the storage chamber through which a heat medium for heating and cooling the hydrogen storage alloy flows, and heat exchange fins in contact with the pipes. The container body is arranged such that the axial direction is along the horizontal direction, and when the storage chamber is bisected in the vertical direction and the upper region is defined as the first region and the lower region is defined as the second region, the total surface area of the heat exchange fins in the second region is larger than the total surface area of the heat exchange fins in the first region.

[0008] A hydrogen storage container according to another aspect of the present invention includes a cylindrical container body having a storage chamber for storing a hydrogen storage alloy, and a plurality of pipes extending along the axial direction of the container body inside the storage chamber through which a heat medium for heating and cooling the hydrogen storage alloy flows. The container body is arranged such that the axial direction is along the horizontal direction, and the container body is provided with a plurality of filling ports for filling the hydrogen storage alloy into the container body.

[0009] Another aspect of the present invention, a hydrogen storage container, includes a cylindrical container body having a storage chamber for housing a hydrogen storage alloy, a plurality of pipes extending along the axial direction of the container body inside the storage chamber through which a heat medium for heating and cooling the hydrogen storage alloy flows, and a plurality of plate fins in contact with the pipes. The container body is arranged such that its axial direction is along the horizontal direction, the plate fins have a flat plate shape extending along the vertical direction, and in the vertical cross-section at the central portion in the axial direction of the container body, the plurality of plate fins are arranged with a gap of 2 mm or more in the horizontal direction.

[0010] A method for charging a hydrogen storage alloy according to one aspect of the present invention is a method for charging a hydrogen storage alloy in a hydrogen storage container including a cylindrical container body having a storage chamber for housing a hydrogen storage alloy, and a plurality of pipes extending along the axial direction of the container body inside the storage chamber through which a heat medium for heating and cooling the hydrogen storage alloy flows. The method includes a step of charging the hydrogen storage alloy into the container body through a plurality of charging ports provided in the container body, and a step of closing the charging ports by welding a lid material to the charging ports. In a top view of the container body, the plurality of charging ports are provided symmetrically with respect to a virtual line passing through the center position of the container body and extending along the axial direction of the container body.

Advantages of the Invention

[0011] According to a hydrogen storage container according to one aspect of the present invention, the temperature distribution of the hydrogen storage alloy inside the container can be made uniform. As a result, the hydrogen absorption and desorption reactions can proceed efficiently.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0013] Hereinafter, with reference to the drawings, an example of an embodiment of a hydrogen storage container according to the present invention will be described in detail. The embodiments described below are merely examples, and the present invention is not limited to the following embodiments. Also, a form formed by selectively combining a plurality of embodiments described below is included in the present invention.

[0014] [First Embodiment] In a hydrogen storage container using a hydrogen storage alloy, in order to increase the hydrogen absorption amount and release amount, it is important to make the temperature distribution of the hydrogen storage alloy inside the container uniform and allow the hydrogen absorption and release reactions to proceed efficiently. Here, as described above, the reaction in which the hydrogen storage alloy releases hydrogen is an endothermic reaction, and the reaction in which the hydrogen storage alloy absorbs hydrogen is an exothermic reaction. Therefore, when allowing the hydrogen storage alloy to absorb hydrogen, the hydrogen storage alloy is cooled, and when releasing hydrogen from the hydrogen storage alloy, the hydrogen storage alloy is heated.

[0015] The hydrogen storage alloy expands or contracts in volume during the absorption and release of hydrogen gas, and is pulverized by repetition. Since the pulverized hydrogen storage alloy tends to accumulate at the bottom of the container, the packing density of the hydrogen storage alloy in the lower region of the container tends to be higher than that in the upper region of the container. As a result, in the lower region of the container, the amount of hydrogen absorbed and released per unit volume increases, and the amount of heat generation and absorption accompanying the hydrogen absorption and release reaction also increases. Specifically, the temperature in the lower region of the container becomes high during hydrogen absorption and low during hydrogen release. As a result, it becomes difficult to efficiently proceed with the hydrogen absorption and release reaction in the lower region of the container, and the amount of hydrogen absorbed and released decreases.

[0016] As will be described in detail later, the hydrogen storage container of the present embodiment includes a pipe through which a heat medium for heating and cooling the hydrogen storage alloy flows inside the container. And, the pipes are arranged more in the lower region of the container than in the upper region of the container. Thereby, the area of contact between the hydrogen storage alloy existing in the lower region of the container and the pipes increases, and the hydrogen storage alloy existing in the lower region of the container can be efficiently heated and cooled. As a result, even when pulverization of the hydrogen storage alloy occurs and the packing density of the hydrogen storage alloy in the lower region of the container increases, the hydrogen absorption and release reaction in the lower region of the container can be efficiently advanced.

[0017] Hereinafter, the hydrogen storage container 1 of the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is an axial cross-sectional view of the hydrogen storage container 1 of the present embodiment, and FIG. 2 is a vertical cross-sectional view at the central portion in the axial direction of the hydrogen storage container 1 of the present embodiment.

[0018] As shown in FIG. 1, the hydrogen storage container 1 includes a container body 10 having an accommodation chamber 30 (not shown) for accommodating a hydrogen storage alloy inside, and a plurality of pipes 40 through which a heat medium for heating and cooling the hydrogen storage alloy flows. The container body 10 is arranged such that its axial direction is along the horizontal direction, and the pipes 40 extend along the axial direction of the container body 10, that is, the horizontal direction, so as to cross the accommodation chamber 30. Further, a plurality of heat exchange fins are joined to the pipes 40. In the present embodiment, plate fins 41 are used as the heat exchange fins. In FIG. 1, in order to clearly show the arrangement relationship inside the container body 10, the illustration of the absorption and release plate 50 described later is omitted, and the number of plate fins 41 is shown to be less than that in the actual case. Also, in FIGS. 1 and 2, the pipes 40 and the plate fins 41 are shown hatched.

[0019] The container body 10 has a cylindrical side wall 11, a first lid 12 that closes the opening at one axial end of the side wall 11, and a second lid 13 that closes the opening at the other axial end of the side wall 11. The first lid 12 and the second lid 13 have a shape in which the central portion bulges outward in the axial direction from the inside of the container body 10.

[0020] In the present embodiment, the cross-sectional shape of the side wall 11 is circular, but it is not limited to this. The cross-sectional shape of the side wall 11 may be, for example, polygonal or elliptical. Also, the wall thickness and size of the side wall 11, the first lid 12, and the second lid 13 can be appropriately selected according to the purpose and the like. Further, as the material of the side wall 11, the first lid 12, and the second lid 13, a material that does not cause hydrogen embrittlement or is less likely to cause hydrogen embrittlement, such as a stainless alloy or an aluminum alloy, can be selected.

[0021] A first partition wall 14 is provided between the side wall 11 and the first lid body 12, and a second partition wall 15 is provided between the side wall 11 and the second lid body 13. As a result, inside the container body 10, there are a storage chamber 30 partitioned by the side wall 11, the first partition wall 14, and the second partition wall 15, a first flow-through chamber 31 partitioned by the first lid body 12 and the first partition wall 14, and a second flow-through chamber 32 partitioned by the second lid body 13 and the second partition wall 15. That is, the first flow-through chamber 31 is provided at one axial end of the storage chamber 30, and the second flow-through chamber 32 is provided at the other axial end of the storage chamber 30.

[0022] Further, the first partition wall 14 and the second partition wall 15 are provided with a plurality of through-holes (not shown) through which the pipe 40 penetrates. As a result, one end of the pipe 40 is connected to the first flow-through chamber 31, and the other end of the pipe 40 is connected to the second flow-through chamber 32. In the present embodiment, the first flow-through chamber 31 and the second flow-through chamber 32 have substantially the same size.

[0023] On the lower end side of the first lid body 12, an inflow portion 16 for allowing a heat medium flowing through the pipe 40 to flow in from outside the container body 10 is provided. As a result, the heat medium flowing in from the inflow portion 16 is stored in the first flow-through chamber 31. Further, on the upper end side of the second lid body 13, an outflow portion 17 for allowing the heat medium flowing through the pipe 40 to flow out to the outside of the container body 10 is provided. As a result, the heat medium flowing into the first flow-through chamber 31 via the inflow portion 16 flows through the pipe 40 and into the second flow-through chamber 32. Then, the heat medium flowing into the second flow-through chamber 32 is discharged to the outside of the container body 10 via the outflow portion 17. By circulating the heat medium through the first flow-through chamber 31 and the second flow-through chamber 32, it becomes possible to circulate the heat medium through all the pipes 40 without directly connecting the pipes 40 to each other. Therefore, the number of parts can be reduced, and the hydrogen storage container 1 can be manufactured at low cost.

[0024] In this embodiment, one inflow portion 16 is provided on the lower end side of the first lid body 12, and one outflow portion 17 is provided on the upper end side of the second lid body 13. Note that the number and arrangement of the inflow portion 16 and the outflow portion 17 are not limited to this. For example, a plurality of inflow portions 16 may be provided on the first lid body 12, and a plurality of outflow portions 17 may be provided on the second lid body 13.

[0025] On the upper part of the side wall 11, two filling ports 18 for filling the hydrogen storage alloy into the inside of the container body 10 are provided. Lid portions 19 are respectively provided on the filling ports 18. After filling the hydrogen storage alloy into the inside of the container body 10, for example, by closing the filling ports 18 with the lid portions 19 by means of flange joining, sealing inside the container body 10 is ensured.

[0026] Also, on the upper part of the side wall 11, a hydrogen circulation portion 20 is provided which allows hydrogen to flow into the inside of the container body 10 during occlusion and allows hydrogen to flow out of the container body 10 during release. The hydrogen circulation portion 20 is connected to, for example, a hydrogen production device (not shown) or the like. Thereby, the hydrogen produced by the above hydrogen production device can be made to flow into the inside of the container body 10. Also, the hydrogen circulation portion 20 is connected to, for example, a pipe connected to a fuel cell (not shown) or a fuel tank (not shown) that supplies hydrogen to the fuel cell. Thereby, the hydrogen flowing out through the hydrogen circulation portion 20 can be supplied to the fuel cell or filled into the fuel tank. Note that the number and arrangement of the hydrogen circulation portions 20 can be appropriately set according to the size of the container body 10 and the like.

[0027] The pipe 40 is a hollow member that extends along the axial direction of the container body 10 inside the accommodation chamber 30 and through which a heat medium flows. In this embodiment, all the pipes 40 have the same shape. The pipe 40 is made of a material with high thermal conductivity. The pipe 40 is fixed by passing through through-holes provided in the first partition wall 14 and the second partition wall 15, with one end connected to the first circulation chamber 31 and the other end connected to the second circulation chamber 32. By arranging the pipe 40 so as to cross the accommodation chamber 30 and flowing a heat medium through the pipe 40, the hydrogen storage alloy accommodated in the accommodation chamber 30 can be efficiently heated or cooled.

[0028] As shown in FIGS. 1 and 2, a region above the virtual line α that bisects the storage chamber 30 in the vertical direction is defined as the first region 30A, and a region below the virtual line α is defined as the second region 30B. The virtual line α is a virtual line that bisects the vertical length of the straight line connecting the upper end and the lower end of the storage chamber 30. At this time, the pipes 40 are arranged such that the number of pipes 40 arranged in the second region 30B is larger than the number of pipes 40 arranged in the first region 30A. Thereby, the area of contact between the hydrogen storage alloy existing in the second region 30B and the pipes 40 increases, and the hydrogen storage alloy existing in the second region 30B can be efficiently heated and cooled. As a result, even when pulverization of the hydrogen storage alloy occurs and the packing density of the hydrogen storage alloy in the second region 30B increases, the hydrogen absorption and desorption reactions in the second region 30B can proceed efficiently. Here, the pipes 40 arranged in the first region 30A or the second region 30B mean the pipes 40 whose entire bodies are arranged in the first region 30A or the second region 30B, excluding the pipes 40 arranged across the first region 30A and the second region 30B.

[0029] Note that if the number of pipes 40 is increased over the entire area of the storage chamber 30, that is, if the number of pipes 40 is increased in both the first region 30A and the second region 30B, the volume of the pipes 40 occupying the storage chamber 30 will increase, and the amount of the hydrogen storage alloy that can be stored inside the storage chamber 30 will decrease. As a result, the amount of the hydrogen storage alloy contributing to the hydrogen absorption and desorption reactions decreases, and the amount of hydrogen absorbed and released decreases. That is, by increasing the number of pipes 40 only in the second region 30B, it is possible to efficiently heat and cool the hydrogen storage alloy existing in the second region 30B while ensuring the amount of the hydrogen storage alloy that can be stored inside the storage chamber 30.

[0030] The number of pipes 40 (P30B) arranged in the second region 30B may be larger than the number of pipes 40 (P30A) arranged in the first region 30A. However, the ratio (P30B / P30A) of the number of pipes 40 (P30B) arranged in the second region 30B to the number of pipes 40 (P30A) arranged in the first region 30A is preferably 1.25 or more, and more preferably 1.5 or more. By setting (P30B / P30A) to 1.25 or more, the area where the hydrogen storage alloy existing in the second region 30B contacts the pipe 40 becomes larger, and the hydrogen storage alloy existing in the second region 30B can be heated and cooled more efficiently. Note that the number of pipes 40 in the first region 30A and the second region 30B can be appropriately set according to the size of the container body 10, the type of hydrogen storage alloy, etc. In the present embodiment, 36 pipes 40 are arranged in the first region 30A and 66 pipes 40 are arranged in the second region 30B.

[0031] As the heat medium flowing inside the pipe 40, for example, water or brine can be used.

[0032] A plurality of plate fins 41 are joined to the pipe 40 as heat exchange fins. The plate fin 41 has a flat plate shape extending in the vertical direction. The plate fin 41 has a through hole (not shown), and the pipe 40 penetrates through the through hole, so that the plate fin 41 is fixed to the pipe 40.

[0033] The plate fins 41 are arranged at substantially equal intervals in the axial direction of the container body 10. And in the storage chamber 30, the hydrogen storage alloy is arranged in the gap between the plate fins 41 so as to contact the plate fins 41. Thereby, the hydrogen storage alloy is heated and cooled via the plate fins 41 in addition to the pipe 40. In other words, by providing the plate fins 41, the hydrogen storage alloy can be heated and cooled efficiently. The interval between the plate fins 41 in the axial direction of the container body 10 can be appropriately set according to the particle size of the hydrogen storage alloy, etc., but is, for example, 1.0 mm or more and 10 mm or less.

[0034] The thickness, number, interval, and size of the plate fins 41 can be set as appropriate. By increasing the number of the plate fins 41 or increasing the size of the plate fins 41, the contact area between the hydrogen storage alloy and the plate fins 41 increases, and the hydrogen storage alloy accommodated in the accommodation chamber 30 can be efficiently heated and cooled. Further, the material of the plate fins 41 is not particularly limited as long as it has a high thermal conductivity, and examples thereof include aluminum alloys.

[0035] As shown in FIG. 2, inside the accommodation chamber 30, two absorption and release plates 50 for exchanging hydrogen existing inside the container body 10 are provided. The absorption and release plate 50 has a frame body 51 having a hollow structure and a filter material 52 provided inside the frame body 51. The absorption and release plate 50 is arranged such that the longitudinal direction of the absorption and release plate 50 extends along the axial direction of the container body 10.

[0036] The frame body 51 is installed inside the container body 10, for example, by engaging with a locking portion (not shown) provided on the inner wall of the container body 10. The frame body 51 has a mesh layer formed on a side surface orthogonal to the thickness direction of the absorption and release plate 50 and has a structure that allows hydrogen to permeate through the side surface. Thereby, the hydrogen existing outside the frame body 51 flows into the inside of the frame body 51 through the side surface of the frame body 51. Further, the hydrogen that has flowed into the inside of the frame body 51 flows out of the frame body 51 through the side surface of the frame body 51.

[0037] The filter material 52 has a function of suppressing the permeation of the hydrogen storage alloy while allowing hydrogen to permeate. Here, inside the container body 10, the hydrogen storage alloy may be lifted up by the flowing hydrogen. And, for example, when hydrogen is released, when hydrogen flows out of the container body 10 through the hydrogen flow passage portion 20 (see FIG. 1), the hydrogen storage alloy may also be drawn into the hydrogen flow passage portion 20. When the hydrogen storage alloy enters the hydrogen flow passage portion 20, the hydrogen flow passage portion 20 may become clogged. By providing the filter material 52 inside the frame body 51 as in the present embodiment, the hydrogen storage alloy is suppressed from moving while being drawn by the flowing hydrogen. As a result, it is possible to suppress the clogging of the hydrogen flow passage portion 20 by the hydrogen storage alloy. As the filter, for example, glass wool, porous sintered metal, and porous inorganic membrane can be used.

[0038] In addition, in the present embodiment, two absorption and desorption plates 50 are provided inside the storage chamber 30, but the number of the absorption and desorption plates 50 may be one or three or more. Also, the absorption and desorption plates 50 may not be provided inside the storage chamber 30.

[0039] [Second Embodiment] The hydrogen storage container 1A which is the second embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is an axial cross-sectional view of the hydrogen storage container 1A of the present embodiment, and FIG. 4 is a vertical cross-sectional view at the central portion in the axial direction of the hydrogen storage container 1A of the present embodiment. In FIG. 3, in order to make the arrangement relationship inside the container body 10 easy to understand, the illustration of the absorption and desorption plate 50 is omitted, and the number of the erofine 42 described later is shown to be smaller than the actual case. Also, in FIGS. 3 and 4, the piping 40 and the erofine 42 are shown by hatching. Hereinafter, the same reference numerals are used for the configurations common to the first embodiment, and the description thereof will be omitted, and mainly the differences from the first embodiment will be described.

[0040] As shown in FIG. 3, the container body 10 of the present embodiment does not have the first lid 12 and the second lid 13. And, an inflow portion 16 and an outflow portion 17 are respectively connected to the ends of some of the pipes 40, and the ends of the pipes 40 are connected via a connection portion 43 so that the flow path from the inflow portion 16 to the outflow portion 17 is continuously drawn in one stroke.

[0041] At this time, the inflow portion 16 is preferably connected to the pipe 40 disposed at the lowermost side among the pipes 40. Thereby, after the heat medium flows through the pipe 40 on the lower side of the container body 10, it flows through the pipe 40 on the upper side of the container body 10.

[0042] Here, the reaction in which the hydrogen storage alloy releases hydrogen is an endothermic reaction, and the reaction in which the hydrogen storage alloy stores hydrogen is an exothermic reaction. Therefore, the amount of heat exchange with the hydrogen storage alloy increases as the heat medium flowing through the inside of the pipe 40 approaches the outflow portion 17 side. When hydrogen is released, the temperature decreases as it approaches the outflow portion 17 side, and when hydrogen is stored, the temperature rises as it approaches the outflow portion 17 side.

[0043] And, as described above, the pulverized hydrogen storage alloy is likely to accumulate in the lower part of the container body 10, and the filling density of the hydrogen storage alloy in the lower region of the container body 10 is likely to increase. Therefore, the hydrogen storage and release reactions on the lower side of the container body 10 become more prominent than the hydrogen storage and release reactions on the upper side of the container body 10. By flowing the heat medium through the inside of the pipe 40 from the lower side to the upper side of the container body 10 as in the present embodiment, the hydrogen storage alloy existing on the lower side of the container body 10 can be efficiently heated and cooled, and the amount of hydrogen storage and release can be increased.

[0044] Also, as shown in FIG. 4, the pipes 40 are arranged such that the number of pipes 40 arranged in the second region 30B is larger than the number of pipes 40 arranged in the first region 30A. As a result, the area where the hydrogen storage alloy existing in the second region 30B contacts the pipes 40 becomes larger, and the hydrogen storage alloy existing in the second region 30B can be efficiently heated and cooled. In the present embodiment, 12 pipes 40 are arranged in the first region 30A and 14 pipes 40 are arranged in the second region 30B.

[0045] In the present embodiment, an erofin 42 is joined to the pipe 40 as a heat exchange fin. The erofin 42 is made of a material having high thermal conductivity, similar to the plate fin 41 of the first embodiment. The erofins 42 are arranged at predetermined intervals in the axial direction of the container body 10. The interval between the erofins 42 in the axial direction of the container body 10 is, for example, 1.0 mm or more and 10 mm or less. The hydrogen storage alloy inside the storage chamber 30 is heated and cooled via the erofins 42.

[0046] [Third Embodiment] The hydrogen storage container 1B according to the third embodiment will be described with reference to FIG. 5. FIG. 5 is an axial cross-sectional view of the hydrogen storage container 1B of the present embodiment. In FIG. 5, in order to clearly show the arrangement relationship inside the container body 10, the illustration of the absorption and release plate 50 is omitted, and the number of plate fins 41 is shown to be smaller than in the actual case. Also, in FIG. 5, the pipes 40 and the plate fins 41 are shown hatched. Hereinafter, the same reference numerals will be used for the configurations common to the first embodiment, and the description thereof will be omitted, and mainly the differences from the first embodiment will be described.

[0047] As shown in FIG. 5, the configuration of the container body 10 of the present embodiment is the same as the configuration of the container body 10 of the first embodiment. On the other hand, in the present embodiment, the number of pipes 40 arranged in the first region 30A and the second region 30B is different from that of the first embodiment in that they are the same respectively.

[0048] In the present embodiment, the number of plate fins 41 is larger on the lower side than on the upper side of the container body 10. More specifically, the interval between the plate fins 41 in the axial direction of the container body 10 is smaller on the lower side of the container body 10 than on the upper side of the container body 10. Thereby, the total surface area of the plate fins 41 in the second region 30B can be made larger than the total surface area of the plate fins 41 in the first region 30A. As described above, the hydrogen storage alloy is heated and cooled via the plate fins 41. Therefore, by making the total surface area of the plate fins 41 in the second region 30B larger than the total surface area of the plate fins 41 in the first region 30A, the area where the hydrogen storage alloy existing in the second region 30B is in contact with the plate fins 41 becomes larger, and the hydrogen storage alloy existing in the second region 30B can be efficiently heated and cooled. As a result, even when pulverization of the hydrogen storage alloy occurs and the packing density of the hydrogen storage alloy in the second region 30B increases, the hydrogen absorption and desorption reaction in the second region 30B can proceed efficiently.

[0049] The surface area (S30B) of the plate fins 41 in the second region 30B only needs to be larger than the surface area (S30A) of the plate fins 41 in the first region 30A, but the ratio (S30B / S30A) of the surface area (S30B) of the plate fins 41 in the second region 30B to the surface area (S30A) of the plate fins 41 in the first region 30A is preferably 1.25 or more, and more preferably 1.5 or more. By setting (S30B / S30A) to 1.25 or more, the area where the hydrogen storage alloy existing in the second region 30B is in contact with the plate fins 41 becomes larger, and the hydrogen storage alloy existing in the second region 30B can be heated and cooled more efficiently.

[0050] In addition, in the present embodiment, the surface area of the plate fins 41 in each region is changed by varying the interval between the plate fins 41 in the axial direction of the container body 10. However, the method of changing the surface area of the plate fins 41 in each region is not limited to this. For example, the surface area of the plate fins 41 in each region may be changed by varying the area of each plate fin 41, that is, by arranging plate fins 41 with a larger area in the second region 30B.

[0051] Also, in the present embodiment, the number of pipes 40 arranged in the first region 30A and the second region 30B is the same. However, as in the first embodiment, the number of pipes 40 arranged in the second region 30B may be larger than the number of pipes 40 arranged in the first region 30A. By increasing the number of pipes 40 arranged in the second region 30B compared to the number of pipes 40 arranged in the first region 30A and making the total surface area of the plate fins 41 in the second region 30B larger than the total surface area of the plate fins 41 in the first region 30A, the hydrogen storage alloy present in the second region 30B can be heated and cooled more efficiently.

[0052] [Fourth Embodiment] The hydrogen storage container 1C according to the fourth embodiment will be described with reference to FIG. 6. FIG. 6 is an axial cross-sectional view of the hydrogen storage container 1C of the present embodiment. In FIG. 6, for clarity of the arrangement relationship inside the container body 10, the illustration of the absorption and desorption plate 50 is omitted, and the number of plate fins 41 is shown to be less than the actual case. Also, in FIG. 6, the pipes 40 and the plate fins 41 are shown hatched. Hereinafter, the same reference numerals are used for the configurations common to the first embodiment, and the description thereof will be omitted, and mainly the differences from the first embodiment will be described.

[0053] As shown in Fig. 6, the hydrogen storage container 1C of the present embodiment is different from the first embodiment in that the outflow portion 17 is connected to the upper end side of the first lid body 12. Further, although details will be described later, the hydrogen storage container 1C of the present embodiment is different from the first embodiment in that partition portions 61 and 62 are provided inside the first circulation chamber 31 and a partition portion 63 is provided inside the second circulation chamber 32.

[0054] As shown in Fig. 6, the container body 10 has, as in the first embodiment, a cylindrical side wall 11, a first lid body 12 that closes the opening at one axial end of the side wall 11, and a second lid body 13 that closes the opening at the other axial end of the side wall 11. Inside the container body 10, a storage chamber 30 partitioned by the side wall 11, the first partition wall 14, and the second partition wall 15, a first circulation chamber 31 partitioned by the first lid body 12 and the first partition wall 14, and a second circulation chamber 32 partitioned by the second lid body 13 and the second partition wall 15 are formed.

[0055] As shown in Fig. 6, in the present embodiment, two partition portions 61 and 62 are provided in the first circulation chamber 31, and one partition portion 63 is provided in the second circulation chamber 32. The partition portions 61, 62, and 63 all have a flat plate shape extending in the horizontal direction.

[0056] The partition portion 61 is provided inside the first circulation chamber 31 at a position below the vertical center portion of the storage chamber 30. Further, the partition portion 62 is provided at a position above the vertical center portion of the storage chamber 30. Thereby, the first circulation chamber 31 is partitioned into a first circulation chamber 31A, a first circulation chamber 31B, and a first circulation chamber 31C. More specifically, the first circulation chamber 31 is composed of a first circulation chamber 31A partitioned by the first lid body 12, the first partition wall 14, and the partition portion 61, a first circulation chamber 31B partitioned by the first lid body 12, the first partition wall 14, the partition portion 61, and the partition portion 62, and a first circulation chamber 31C partitioned by the first lid body 12, the first partition wall 14, and the partition portion 62.

[0057] The partition portion 63 is provided inside the second circulation chamber 32 at a position below the vertical center of the storage chamber 30, and is provided to separate the second circulation chamber 32 into two spaces. Therefore, the second circulation chamber 32 is partitioned by the partition portion 63 into a second circulation chamber 32A that constitutes the lower space of the second circulation chamber 32 and a second circulation chamber 32B that constitutes the upper space of the second circulation chamber 32.

[0058] As described above, one end of the pipe 40 is connected to the first circulation chamber 31. Therefore, the end of the pipe 40 that is disposed in the lower region when the container body 10 is bisected in the vertical direction is connected to the first circulation chamber 31A. And the end of the pipe 40 that is disposed in the upper region when the container body 10 is bisected in the vertical direction is connected to the first circulation chamber 31C.

[0059] Similarly, the other end of the pipe 40 is connected to the second circulation chamber 32. Therefore, the end of the pipe 40 that is disposed in the lower region when the container body 10 is bisected in the vertical direction is connected to the second circulation chamber 32A.

[0060] As shown in FIG. 6, an inflow portion 16 for allowing the heat medium flowing through the pipe 40 to flow into the container body 10 from the outside is provided on the lower end side of the first lid body 12, that is, the portion of the first lid body 12 that partitions the first circulation chamber 31A. Thereby, the inflow portion 16 is connected to the first circulation chamber 31A. Further, an outflow portion 17 for allowing the heat medium flowing through the pipe 40 to flow out of the container body 10 is provided on the upper end side of the first lid body 12, that is, the portion of the first lid body 12 that partitions the first circulation chamber 31C. Thereby, the outflow portion 17 is connected to the first circulation chamber 31C.

[0061] Here, the flow path of the heat medium will be described. The heat medium flows into and is stored in the first flow-through chamber 31A via the inflow portion 16. The heat medium stored in the first flow-through chamber 31A flows through the pipe 40 into the second flow-through chamber 32A. Then, the heat medium that has flowed into the second flow-through chamber 32A flows through the pipe 40 into the first flow-through chamber 31B, and the heat medium that has flowed into the first flow-through chamber 31B flows through the pipe 40 into the second flow-through chamber 32B. Then, the heat medium that has flowed into the second flow-through chamber 32B flows through the pipe 40 into the first flow-through chamber 31C and flows out of the container body 10 through the outflow portion 17. That is, the heat medium flows through the pipe 40 on the lower side of the container body 10 and then through the pipe 40 on the upper side of the container body 10.

[0062] As a result of the study by the present inventors, as shown in FIG. 1, when the partition portions 61, 62, and 63 are not provided in the first flow-through chamber 31 and the second flow-through chamber 32 and the outflow portion 17 is connected to the second flow-through chamber 32, it has been found that during hydrogen occlusion, the temperature of the hydrogen occlusion alloy disposed in the lower region of the storage chamber 30 may be higher than the temperature of the hydrogen occlusion alloy disposed in the upper region of the storage chamber 30. This is presumably because when the partition portions 61, 62, and 63 are not provided, the flow rate of the heat medium flowing through the pipe 40 disposed in the lower region of the container body 10 becomes smaller than the flow rate of the heat medium flowing through the pipe 40 disposed in the upper region of the container body 10. When the flow rate of the heat medium becomes smaller, the flow rate of the heat medium flowing through the pipe 40 decreases, and the amount of heat exchange between the heat medium and the hydrogen occlusion alloy becomes smaller. As a result, during hydrogen occlusion, it becomes difficult to sufficiently cool the hydrogen occlusion alloy disposed in the lower region of the storage chamber 30, the hydrogen occlusion reaction cannot proceed efficiently, and the amount of hydrogen occlusion may decrease.

[0063] On the one hand, as in this embodiment, by providing partition portions 61, 62, and 63 in the first flow-through chamber 31 and the second flow-through chamber 32 respectively, the heat medium flows through the pipe 40 disposed in the lower region of the container main body 10 and then through the pipe 40 disposed in the upper region of the container main body 10. Thereby, the heat exchange amount between the heat medium and the hydrogen storage alloy can be increased. As a result, during hydrogen storage, it becomes easy to sufficiently cool the hydrogen storage alloy disposed in the lower region of the storage chamber 30, the hydrogen absorption reaction can proceed efficiently, and the hydrogen storage amount can be increased.

[0064] In this embodiment, two partition portions 61 and 62 are provided in the first flow-through chamber 31, and one partition portion 63 is provided in the second flow-through chamber 32. However, the configuration of the partition portions is not limited to this. For example, three or more partition portions may be provided in the first flow-through chamber 31, or two or more partition portions may be provided in the second flow-through chamber 32. Also, the second flow-through chamber 32 may not be provided with a partition portion. Further, in this embodiment, the outflow portion 17 is provided on the upper end side of the first lid body 12, but it is not limited to this. The outflow portion 17 may be provided on the second lid body 13, for example. That is, the outflow portion 17 may be connected to the second flow-through chamber 32.

[0065] [Fifth Embodiment] With reference to FIGS. 7 and 8, the hydrogen storage container 1D which is the fifth embodiment will be described. FIG. 7 is a top view of the hydrogen storage container 1D of this embodiment, and FIG. 8 is a vertical cross-sectional view at the central portion in the axial direction of the hydrogen storage container 1D of this embodiment. Hereinafter, for the configurations common to the first embodiment, the same reference numerals will be used and the overlapping descriptions will be omitted, and mainly the differences from the first embodiment will be described.

[0066] As a result of the inventors' studies, it has become clear that if there are uneven distributions of the hydrogen storage alloy inside the container body 10, the amount of hydrogen absorption and release will decrease. When there are uneven distributions of the hydrogen storage alloy, in regions with a high density of the hydrogen storage alloy, the hydrogen absorption and release reactions tend to concentrate and occur more easily. Therefore, when hydrogen is absorbed, the temperature in that region becomes higher than in other regions, and when hydrogen is released, the temperature in that region becomes lower than in other regions. As a result, in regions with a high density of the hydrogen storage alloy, it becomes difficult to efficiently progress the hydrogen absorption and release reactions, and the overall amount of hydrogen absorption and release decreases. That is, in order to efficiently progress the hydrogen absorption and release reactions, it is important to suppress the uneven distribution of the hydrogen storage alloy inside the container body 10 and to equalize the temperature distribution of the hydrogen storage alloy inside the container body 10 during hydrogen absorption and release.

[0067] As shown in FIG. 7, the hydrogen storage container 1D of the present embodiment is provided with six filling ports 18 for filling the inside of the container body 10 with the hydrogen storage alloy. Each filling port 18 is sealed by a lid portion 19. By providing a plurality of filling ports 18, when filling the hydrogen storage alloy, the hydrogen storage alloy is not concentrated in one place inside the container body 10 but is dispersed. As a result, the temperature distribution of the hydrogen storage alloy inside the container body 10 can be equalized.

[0068] It is preferable that the plurality of filling ports 18 are provided at substantially equal intervals in the axial direction of the container body 10. In this case, it becomes easier to arrange the hydrogen storage alloy more uniformly inside the container body 10.

[0069] The number of filling ports 18 can be appropriately set according to the axial length and inner diameter of the container body 10, etc. The filling ports 18 are preferably provided at positions where the interval between adjacent filling ports 18 in the axial direction of the container body 10 is less than the inner diameter of the container body 10 in a top view of the container body 10. If the interval between adjacent filling ports 18 exceeds the inner diameter of the container body 10, there may be a location inside the container body 10 where it is difficult to arrange the hydrogen storage alloy.

[0070] As shown in FIG. 8, the filling port 18 is provided such that the opening direction of the filling port 18 follows a direction inclined in the circumferential direction of the container body 10 with respect to the vertical direction. By inclining the opening direction of the filling port 18 along the circumferential direction of the container body 10 with respect to the vertical direction, when filling the hydrogen storage alloy, it becomes difficult for the hydrogen storage alloy to be obstructed by the piping 40 or the heat exchange fins inside the container body 10. As a result, inside the container body 10, the hydrogen storage alloy is more dispersedly arranged.

[0071] The inclination angle of the opening direction of the filling port 18 with respect to the vertical direction is preferably 5° or more and 30° or less. If the inclination angle exceeds 30°, it may be difficult to fill the hydrogen storage alloy up to the upper side of the container body 10.

[0072] In the present embodiment, the filling port 18 includes first filling ports 18A, 18B, 18C provided such that the opening direction of the filling port 18 follows a direction inclined toward one side in the circumferential direction of the container body 10 with respect to the vertical direction, and second filling ports 18D, 18E, 18F provided such that the opening direction of the filling port 18 follows a direction inclined toward the other side in the circumferential direction of the container body 10 with respect to the vertical direction. And the first filling port 18A and the second filling port 18D are provided substantially on the same straight line in the circumferential direction of the container body 10, the first filling port 18B and the second filling port 18E are provided substantially on the same straight line in the circumferential direction of the container body 10, and the first filling port 18C and the second filling port 18F are provided substantially on the same straight line in the circumferential direction of the container body 10. By including the first filling ports 18A, 18B, 18C and the second filling ports 18D, 18E, 18F in the filling port 18, it becomes easy to disperse the hydrogen storage alloy throughout the inside of the container body 10.

[0073] As shown in FIG. 8, a plurality of plate fins 41 are joined to the pipe 40. The plate fins 41 have a flat plate shape extending along the vertical direction. And in the vertical cross-section, the horizontally adjacent plate fins 41 do not contact each other and are arranged with a gap (D) therebetween. At this time, it is preferable that the plate fins 41 are arranged such that the gap (D) is 2 mm or more. By setting the gap (D) between the plate fins 41 to 2 mm or more, when the hydrogen storage alloy is introduced into the container body 10 from the filling port 18, the hydrogen storage alloy is filled into the lower part of the container body 10 through the gap between the plate fins 41. In other words, when the gap (D) is less than 2 mm, when the hydrogen storage alloy is introduced into the container body 10 from the filling port 18, the hydrogen storage alloy may be blocked by the plate fins 41 and may not reach the lower part of the container body 10. As a result, uneven distribution of the hydrogen storage alloy occurs inside the container body 10. The upper limit value of the gap (D) is, for example, 10 mm from the viewpoint of ensuring the area where the plate fins 41 and the hydrogen storage alloy are in contact and efficiently heating and cooling the hydrogen storage alloy. Therefore, in the vertical cross-section, the gap (D) between the horizontally adjacent plate fins 41 is preferably 2 mm or more and 10 mm or less.

[0074] [Sixth Embodiment] With reference to FIG. 9, the hydrogen storage container 1E according to the sixth embodiment and the method of introducing the hydrogen storage alloy into the hydrogen storage container 1E will be described. FIG. 9 is a top view of the hydrogen storage container 1E of the present embodiment, and is a top view of the hydrogen storage container 1E in a state before a welding process to be described later. Hereinafter, the same reference numerals are used for the configurations common to the first embodiment, and the description thereof will be omitted, and mainly the differences from the first embodiment will be described.

[0075] As described above, in order to efficiently progress the hydrogen absorption and desorption reactions, it is important to make the distribution of the hydrogen storage alloy inside the container body 10 uniform and to make the temperature distribution of the hydrogen storage alloy inside the container body 10 uniform during hydrogen absorption and desorption. Although it will be described in detail later, on the upper surface of the hydrogen storage container 1E of the present embodiment, in addition to the two filling ports 18, a plurality of charging ports 21 for filling the hydrogen storage alloy into the inside of the container body 10 are provided. By providing the plurality of charging ports 21, the distribution of the hydrogen storage alloy inside the container body 10 can be made more uniform.

[0076] The method of charging the hydrogen storage alloy in the hydrogen storage container 1E includes a charging step of charging the hydrogen storage alloy into the inside of the container body 10 through the charging port 21, and a welding step of welding a lid material (not shown) to the charging port 21 to close the charging port 21. In the charging step, the hydrogen storage alloy may be charged into the inside of the container body 10 from each of the charging ports 21 in order, or the hydrogen storage alloy may be charged into the inside of the container body 10 simultaneously from the five charging ports 21. Further, the welding method in the welding step is not particularly limited as long as it is possible to close the charging port 21 and seal the inside of the storage chamber 30. For example, laser welding may be mentioned. Further, the material of the lid material welded to the charging port 21 is a material that does not cause hydrogen embrittlement or is less likely to cause hydrogen embrittlement, such as a stainless alloy or an aluminum alloy, similar to the container body 10.

[0077] Here, as shown in FIG. 9, the five charging ports 21 are provided symmetrically with respect to a virtual line β that passes through the center position of the container body 10 and extends along the axial direction of the container body 10 in a top view of the container body 10. By providing the plurality of charging ports 21 symmetrically with respect to the virtual line β, the distribution of the hydrogen storage alloy inside the container body 10 can be made more uniform. The number of the charging ports 21 can be appropriately set according to the axial length and inner diameter of the container body 10 and the like.

Explanation of symbols

[0078] 1, 1A, 1B, 1C, 1D, 1E hydrogen storage container, 10 container body, 11 side wall, 12 first lid, 13 second lid, 14 first partition, 15 second partition, 16 inlet part, 17 outlet part, 18 filling port, 18A, 18B, 18C first filling port, 18D, 18E, 18F second filling port, 19 lid part, 20 hydrogen flow part, 21 input port, 30 accommodation chamber, 30A first region, 30B second region, 31 first flow chamber, 32 second flow chamber, 40 pipe, 41 plate fin (heat exchange fin), 42 erofin (heat exchange fin), 43 connection part, 50 absorption and release plate, 51 frame body, 52 filter material, 61, 62, 63 partition part, α, β virtual line

Claims

1. A cylindrical container body having a storage chamber for storing a hydrogen storage alloy, A plurality of pipes that extend along the axial direction of the container body inside the storage chamber and through which a heat medium for heating and cooling the hydrogen storage alloy flows, Comprising: The container body is arranged such that the axial direction is along the horizontal direction, When the storage chamber is bisected in the vertical direction, with the upper region being the first region and the lower region being the second region, A hydrogen storage container, wherein the number of pipes arranged in the second region is greater than the number of pipes arranged in the first region.

2. The hydrogen storage container according to claim 1, further comprising heat exchange fins that contact the pipes.

3. A cylindrical container body having a storage chamber for storing a hydrogen storage alloy, A plurality of pipes that extend along the axial direction of the container body inside the storage chamber and through which a heat medium for heating and cooling the hydrogen storage alloy flows, Heat exchange fins that contact the pipes, Comprising: The container body is arranged such that the axial direction is along the horizontal direction, When the storage chamber is bisected in the vertical direction, with the upper region being the first region and the lower region being the second region, A hydrogen storage container, wherein the total surface area of the heat exchange fins in the second region is larger than the total surface area of the heat exchange fins in the first region.

4. The hydrogen storage container according to claim 2 or 3, wherein the heat exchange fins are plate fins or louver fins.

5. Inside the container body, at both axial ends of the storage chamber, a pair of flow-through chambers partitioned from the storage chamber by a partition wall and to which the ends of the pipes are connected are provided. The hydrogen storage container according to any one of claims 1 to 3.

6. Connected to the pair of flow-through chambers are an inlet portion for allowing a heat medium flowing through the pipes to flow into the container body from the outside, and an outlet portion for allowing the heat medium flowing through the pipes to flow out of the container body to the outside. The hydrogen storage container according to claim 5, wherein the inlet portion is provided below the outlet portion.

7. Connected to the pipes are an inlet portion for allowing a heat medium flowing through the pipes to flow into the container body from the outside, and an outlet portion for allowing the heat medium flowing through the pipes to flow out of the container body to the outside. The hydrogen storage container according to any one of claims 1 to 3, wherein the pipes are connected such that the flow path from the inlet portion to the outlet portion is continuously connected in one stroke.

8. Inside the container body, a hydrogen absorption and desorption plate for transferring hydrogen existing inside the container body is provided. The longitudinal direction of the hydrogen absorption and desorption plate extends along the axial direction of the container body. The hydrogen storage container according to any one of claims 1 to 3.

9. A cylindrical container body having a storage chamber for storing a hydrogen storage alloy, A plurality of pipes extending along the axial direction of the container body inside the storage chamber and through which a heat medium for heating and cooling the hydrogen storage alloy flows, Comprising, The container body is arranged such that the axial direction is along the horizontal direction, The container body is provided with a plurality of filling ports for filling the hydrogen storage alloy into the inside of the container body. The hydrogen storage container.

10. The plurality of filling ports are provided at substantially equal intervals in the axial direction of the container body. The hydrogen storage container according to claim 9.

11. The container body has a cylindrical shape, In a top view of the container body, the distance between adjacent filling ports in the axial direction of the container body is less than the inner diameter of the container body. The hydrogen storage container according to claim 9 or 10.

12. The container body has a cylindrical shape, At least one of the plurality of filling ports has an opening direction inclined along the circumferential direction with respect to the vertical direction. The hydrogen storage container according to claim 9.

13. The plurality of filling ports, A first filling port provided such that the opening direction of the filling port is along a direction inclined to one side in the circumferential direction of the container body with respect to the vertical direction, A second filling port provided such that the opening direction of the filling port is along a direction inclined to the other side in the circumferential direction of the container body with respect to the vertical direction, Including, The inclination angle of the opening direction of the first filling port with respect to the vertical direction is substantially the same as the inclination angle of the opening direction of the second filling port with respect to the vertical direction. The hydrogen storage container according to claim 12.

14. The inclination angle of the opening direction with respect to the vertical direction is 5° or more and 30° or less. The hydrogen storage container according to claim 12 or 13.

15. A cylindrical container body having a storage chamber for storing a hydrogen storage alloy, A plurality of pipes extending along the axial direction of the container body inside the storage chamber and through which a heat medium for heating and cooling the hydrogen storage alloy flows, A plurality of plate fins in contact with the pipes, Comprising, The container body is arranged such that the axial direction is along the horizontal direction, The plate fin has a flat plate shape extending along the vertical direction. A hydrogen storage container, in a vertical cross-section at the axial center of the container body, a plurality of the plate fins are arranged with a horizontal interval of 2 mm or more.

16. The hydrogen storage container according to claim 15, wherein in a vertical cross-section at the axial center of the container body, a plurality of the plate fins are arranged with a horizontal interval of 2 mm or more and 10 mm or less.

17. A cylindrical container body having a storage chamber for storing a hydrogen storage alloy, a method for charging a hydrogen storage alloy in a hydrogen storage container including a plurality of pipes extending along the axial direction of the container body inside the storage chamber and through which a heat medium for heating and cooling the hydrogen storage alloy flows, comprising: a step of charging the hydrogen storage alloy into the container body through a plurality of charging ports provided in the container body; a step of welding a lid material to the charging port to close the charging port; comprising a method for charging a hydrogen storage alloy, wherein in a top view of the container body, a plurality of the charging ports are provided at axially symmetric positions with respect to a virtual line passing through the center position of the container body and extending along the axial direction of the container body.

Images