JP2007016988A - High-pressure tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pressure tank capable of controlling overheating of a tank in charging a gas while reducing equipment costs. <P>SOLUTION: This high-pressure tank 1 comprising a vessel main body 10 for storing the gas, comprises a cold insulation layer 30 formed in a state of covering at least a part of the vessel main body 10. When the vessel main body 10 is cooled in discharging the gas from the high-pressure tank 1 and a temperature of the vessel main body 10 is lowered, the cold is recovered and preserved in the cold insulation layer 30, and when the vessel main body 10 is heated in charging the gas to the high-pressure tank 1, the vessel main body 10 is cooled by the cold insulation layer 30. The cold insulation layer 30 has rigidity lower than that of the vessel main body 10, and a buffering function for protecting the vessel main body 10 from external impact shock. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a high-pressure tank, and more particularly to a high-pressure tank that stores fuel gas such as hydrogen gas or natural gas at high pressure.

  Fuel cell vehicles and natural gas vehicles are equipped with high-pressure tanks for storing hydrogen gas or natural gas as fuel gas. Conventional high-pressure tanks were composed of a metal liner (inner layer) that is in direct contact with the fuel gas, and a fiber reinforced resin layer (outer layer) laminated on the outer peripheral surface of the liner. In order to reduce the weight, a high-pressure tank using a resin liner is provided.

  However, a high-pressure tank using a resin liner has a characteristic that its heat transfer coefficient is lower than that of a high-pressure tank using a metal liner, causing the following problems. First, when the fuel gas is filled into the high-pressure tank, the temperature in the tank rises rapidly as the fuel gas is compressed, but the high-pressure tank using a resin liner has a low heat transfer coefficient, so It takes a long time for the tank to cool and return to room temperature, and the high temperature state of the tank continues for a long time and becomes overheated. Therefore, in preparation for overheating of the tank, it is necessary to adopt a material having excellent heat resistance, which causes a problem that the manufacturing cost of the tank increases.

  In order to solve such a problem, a groove serving as a refrigerant path is provided on the outer surface of the thick part of the liner constituting the container body of the high-pressure tank, and the coolant is caused to flow between the fuel gas and the refrigerant inside the container body. A technique for cooling the container body by performing heat exchange has been proposed (see, for example, Patent Document 1).

  However, in the technique described in Patent Document 1, in addition to equipment for supplying refrigerant to the refrigerant path from the outside, a heat radiating device for cooling the heated refrigerant by exchanging heat with fuel gas ( Since it is necessary to provide a separate radiator, etc., there is a problem that equipment costs increase.

Further, when the fuel gas is discharged from the high-pressure tank, the temperature in the tank decreases as the fuel gas expands. However, since the high-pressure tank has a low heat transfer coefficient as described above, the tank is warmed by the outside air. The temperature drop in the tank precedes the tank, and the tank is excessively cooled. Therefore, measures such as providing a cooling fin in the tank are taken to suppress overcooling of the tank, but there has been a problem that a space for installing the fin has to be secured.
JP 2003-65437 A

  As described above, in the conventional high-pressure tank, it is necessary to take measures against the overheating of the tank that occurs when the fuel gas is filled, and also consider the overcooling of the tank that occurs when the fuel gas is discharged. Countermeasures are necessary. This means that there is a temperature zone suitable for use in the high-pressure tank. In the conventional high-pressure tank, it has been strongly desired to establish a technique for keeping the temperature of the tank in the zone.

  An object of the present invention is to suppress overheating of a tank that occurs at the time of gas filling and overcooling of a tank that occurs at the time of gas release while reducing the equipment cost and installation space in a high-pressure tank.

  In order to achieve the above object, a high-pressure tank according to the present invention is a high-pressure tank that stores gas, and includes a heat storage material.

  In the high-pressure tank, the heat storage material stores thermal energy by releasing thermal energy that accompanies a phase change of the gas stored in the high-pressure tank, and heat energy that accompanies a phase change opposite to the phase change. It is preferable that the material is a latent heat storage material that suppresses supercooling due to absorption of heat by the heat stored when the heat energy is released. Alternatively, the heat storage material stores cold energy by absorption of thermal energy that accompanies the phase change of the gas stored in the high-pressure tank, and releases heat energy that accompanies a phase change opposite to the phase change. It is preferably a latent heat storage material that suppresses overheating by the cold energy stored when the thermal energy is absorbed.

  The high-pressure tank preferably includes a container main body that stores gas, and a base that is attached to the container main body and fills the container main body with gas or releases gas from the container main body. It may be provided, or may be provided on at least a part of the container body.

  According to such a configuration, the supercooling of the tank that occurs at the time of gas discharge is suppressed by the heat stored in the heat storage material at the time of gas filling before that. Moreover, the overheating of the tank which occurs at the time of gas filling is suppressed by the cold energy stored in the heat storage material at the time of the previous gas discharge. As a result, the tank temperature is maintained in a suitable zone.

  The high-pressure tank according to the present invention is a high-pressure tank including a container main body that stores gas, and includes a cold insulation layer provided to cover at least a part of the container main body.

  According to such a configuration, since the cold insulation layer is provided so as to cover at least a part of the container main body, when the container main body is cooled when the gas is discharged from the high-pressure tank and the container main body becomes low temperature, The low temperature can be recovered and stored in the cold insulation layer. Therefore, when the container main body is heated at the time of gas filling to the high-pressure tank, the container main body can be cooled by the cold insulation layer, and overheating of the tank can be suppressed. As a result, it is possible to reduce or avoid the use of heat-resistant materials, and it is not necessary to provide a separate heat dissipating device, so that the manufacturing cost and equipment cost of the tank can be reduced.

  In the high-pressure tank, the cold insulation layer preferably has a rigidity equal to or lower than the rigidity of the container body. By doing so, it is possible to allow deformation of the container body accompanying heating and cooling. The cold insulation layer preferably has a buffer function for protecting the container body from external impacts. By doing so, it is possible to effectively protect the container body without separately providing a cushioning material.

  The high-pressure tank according to the present invention is a high-pressure tank comprising a container main body for storing gas, and is provided with a cold insulation chamber provided so as to cover at least a part of the container main body and filled with a predetermined cold insulation agent. It is to be prepared.

  According to such a configuration, since the cold storage chamber filled with the cold insulating agent is provided so as to cover at least a part of the container main body, the container main body is cooled when the gas is discharged from the high-pressure tank, and the container main body is cooled to a low temperature. If this happens, the low temperature can be recovered and stored in a cold room. Therefore, when the container main body is heated when the high-pressure tank is filled with gas, the container main body can be cooled by the cold insulation chamber, and the tank can be prevented from being overheated. As a result, it is possible to reduce or avoid the use of heat-resistant materials, and it is not necessary to provide a separate heat dissipating device, so that the manufacturing cost and equipment cost of the tank can be reduced.

  In the high-pressure tank, the cold-reserving chamber can be configured to be supplied with a predetermined cold-retaining agent after gas is released from the container body. By doing so, the low-temperature state of the container body cooled due to gas discharge can be efficiently stored. Further, the cold storage chamber can be configured such that a predetermined cold storage agent is supplied after the container body is filled with gas. By carrying out like this, the container main body heated by gas filling can be cooled efficiently.

  In the high-pressure tank, it is preferable that the cold insulation chamber has a rigidity equal to or lower than the rigidity of the container body. By doing so, it is possible to allow deformation of the container body accompanying heating and cooling. Moreover, it is preferable that the cold insulation chamber has a buffer function for protecting the container body from an external impact. By doing so, it is possible to effectively protect the container body without separately providing a cushioning material.

  In the high-pressure tank, the container body can be configured to have an inner layer made of a resin material and in direct contact with the gas, and an outer layer made of a fiber reinforced resin material and provided outside the inner layer. The high-pressure tank stores high-pressure hydrogen gas and can be mounted on a fuel cell vehicle.

  According to the present invention, in a high-pressure tank, by keeping the tank temperature in a suitable band, the tank is overheated at the time of gas filling and the tank is supercooled at the time of gas discharge while reducing the equipment cost and installation space. Can be effectively suppressed.

  Hereinafter, a high-pressure tank according to an embodiment of the present invention will be described with reference to the drawings. The high-pressure tank according to each of the following embodiments is for storing fuel gas (hydrogen gas) mounted on a fuel cell vehicle.

<First Embodiment>
First, the high-pressure tank 1 according to the first embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the high-pressure tank 1 includes a container body 10 that stores hydrogen gas, and a gas filling / release port 20 that realizes filling of the container body 10 with hydrogen gas and release of hydrogen gas from the container body 10. And a cold insulation layer 30 provided so as to cover the container body 10.

  As shown in FIG. 1, the container main body 10 includes a cylindrical body portion 11 and dome portions 12 provided at both ends of the body portion 11. The body portion 11 and the dome portion 12 are It is composed of a two-layer wall body composed of a liner (inner layer) and a fiber reinforced resin layer (outer layer). The liner is a layer in direct contact with hydrogen gas, and is made of a resin material. The thickness of the liner and the type of resin material constituting the liner are appropriately determined according to the airtightness and moldability required for the liner. The fiber reinforced resin layer is a layer that is provided so as to cover the outside of the liner and reinforces the liner, and is composed of reinforcing fibers and a matrix resin.

  A thermoplastic resin and a thermosetting resin can be employed as the resin constituting the liner or the fiber reinforced resin layer. As the thermoplastic resin, polyethylene, polypropylene, polyvinyl chloride, ABS resin, polystyrene, polyamide, polycarbonate, polyimide, fluorine resin, etc. can be adopted, and as the thermosetting resin, epoxy resin, polyurethane, etc. are adopted. be able to. Moreover, glass fiber, carbon fiber, aramid fiber, etc. are employable as a reinforced fiber which comprises a fiber reinforced resin layer.

  The gas filling / releasing port 20 is connected to one dome portion 12 of the container body 10 and includes a valve (not shown) for realizing filling / releasing of hydrogen gas. An annular base 21 is provided at a portion of the container body 10 where the gas filling / releasing port 20 is connected. When the container body 10 is filled with hydrogen gas from the gas filling / release port 20, the temperature of the hydrogen gas rises due to the compression of the hydrogen gas, and the container body 10 is heated. On the other hand, when the hydrogen gas in the container main body 10 is released from the gas filling / release port 20, the temperature of the hydrogen gas decreases due to the expansion of the hydrogen gas, and the container main body 10 is cooled.

  The cold insulation layer 30 is a layer provided so as to cover the dome portion 12 of the container body 10, and when the hydrogen gas is released from the high-pressure tank 1, the container body 10 is cooled and the container body 10 becomes low temperature. In this case, it has a cold insulation function for recovering and storing the low temperature. Moreover, the cold insulation layer 30 in this embodiment shall have a buffer function which protects the container main body 10 from an external impact, and it is not necessary to provide a buffer material separately. In the present embodiment, the cold insulation layer 30 is made of a material having a rigidity equal to or lower than the rigidity of the container body 10 (for example, a material having a rigidity of 10% or less of the axial rigidity of the container body 10), and is heated or cooled. The container body 10 is allowed to be deformed due to the above.

  The cold insulation layer 30 can adopt any configuration as long as it has the above-described cold insulation function and buffer function and has a rigidity equal to or lower than the rigidity of the container body 10. For example, gelling or thickening an aqueous solution containing a cryogen and enclosing it in a synthetic resin bag, impregnating a porous body with an aqueous solution containing a cryogen and enclosing it in a synthetic resin bag, or a room temperature gel that acts as a cryogen A material obtained by impregnating a porous material with a substance can be used as the cold insulation layer 30. As the cryogen, a mixture of parabenzoate ester, calcium hydroxide, and carboxymethyl cellulose in a predetermined ratio, ethylene glycol, ammonia, or the like can be used. Moreover, as a porous body, elastic foams, such as a urethane foam, are employable.

  In the high-pressure tank 1 according to the embodiment described above, since the cold insulation layer 30 is provided so as to cover the dome portion 12 of the container body 10, the container body 10 is cooled when hydrogen gas is released from the high-pressure tank 1. When the container body 10 becomes low temperature, the low temperature can be recovered and stored in the cold insulation layer 30. Therefore, when the container main body 10 is heated when the high-pressure tank 1 is filled with hydrogen gas, the container main body 10 can be cooled by the cold insulation layer 30, and overheating of the high-pressure tank 1 can be suppressed. As a result, it is possible to reduce or avoid the use of a heat-resistant material, and it is not necessary to provide a separate heat dissipating device, so that the manufacturing cost and equipment cost of the high-pressure tank 1 can be reduced.

  In the above embodiment, an example in which the cold insulation layer 30 is provided so as to cover the dome portion 12 of the container main body 10 is shown. However, as shown in FIG. 2, the trunk portion 11 and the base 21 of the container main body 10 are provided. The cold insulation layers 40 and 50 may be provided so as to cover the surface. Further, a cold insulation layer may be provided so as to cover the entire container body 10 (the trunk portion 11 and the dome portion 12).

Second Embodiment
Next, a high-pressure tank 1A according to a second embodiment of the present invention will be described with reference to FIG. The high pressure tank 1A according to the present embodiment is provided with a cold insulation chamber 30A in place of the cold insulation layer 30 of the high pressure tank 1 according to the first embodiment, and other configurations are substantially the same as those of the first embodiment. It is. For this reason, it demonstrates centering around the changed structure, and attaches | subjects the code | symbol same about the part which is common in 1st Embodiment, and abbreviate | omits the description.

  As shown in FIG. 3, the high-pressure tank 1 </ b> A according to the present embodiment includes a container main body 10 that stores hydrogen gas, and a gas that realizes filling of the container main body 10 with hydrogen gas and releasing of hydrogen gas from the container main body 10. A filling / release port 20 and a cold insulation chamber 30 </ b> A provided to cover the container body 10 are provided. Since the container body 10 and the gas filling / outflow port 20 are substantially the same as those described in the first embodiment, description thereof will be omitted.

  The cold insulation chamber 30A is a hollow casing provided so as to cover the body portion 11 of the container main body 10. The inside of the cold insulation chamber 30A is filled with the cold insulation agent C, and the hydrogen gas is released from the high-pressure tank 1A. When the main body 10 is cooled and the container main body 10 becomes a low temperature, it has a cold insulation function for recovering and storing the low temperature. In the present embodiment, as shown in FIG. 3, the coolant C stored in the coolant tank 31A is supplied to the cool chamber 30A from below by the pump 32A, and the opening / closing operation of the opening / closing valve 33A is controlled. The charging / discharging of the cooling agent C in the cooling chamber 30A is realized.

  As the cooling agent C, an aqueous solution containing a cryogen can be employed. As the cryogen, a mixture of parabenzoate ester, calcium hydroxide, and carboxymethyl cellulose in a predetermined ratio, ethylene glycol, ammonia, or the like can be used.

  In this embodiment, the operation of the pump 32A is controlled by a control device (not shown) to adjust the supply timing of the cooling agent C to the cold storage chamber 30A, thereby cooling the container body 10 and reducing the temperature. It is possible to efficiently realize both the recovery and the recovery. Specifically, the control device efficiently supplies the cold insulating agent C to the cold insulation chamber 30A immediately after the hydrogen gas is released from the container main body 10 and the container main body 10 is cooled, thereby efficiently reducing the low temperature state of the container main body 10. Can be saved. On the other hand, the control device can efficiently cool the container body 10 by supplying the cold insulation agent C to the cold insulation chamber 30A immediately after the container body 10 is filled with hydrogen gas and the container body 10 is heated.

  In the high-pressure tank 1A according to the embodiment described above, since the cold-reserving chamber 30A filled with the cold-retaining agent C is provided so as to cover the body portion 11 of the container main body 10, hydrogen gas is released from the high-pressure tank 1A. When the container main body 10 is sometimes cooled and the container main body 10 becomes low temperature, the low temperature can be recovered and stored in the cold insulation chamber 30A. Therefore, when the container main body 10 is heated when the high-pressure tank 1A is filled with hydrogen gas, the container main body 10 can be cooled by the cold insulation chamber 30A, and overheating of the high-pressure tank 1 can be suppressed. As a result, the use of heat-resistant materials can be reduced or avoided, and further, since it is not necessary to provide a separate heat dissipation device, the manufacturing cost and equipment cost of the high-pressure tank 1A can be reduced.

  Further, in the high-pressure tank 1A according to the embodiment described above, the cold insulation chamber 30A is supplied with the cold insulation agent C after the container body 10 is filled with hydrogen gas. Thus, the heated container body 10 can be cooled very efficiently. Further, since the cold insulation agent C is supplied to the cold insulation chamber 30A after the hydrogen gas is released from the container main body 10, the low temperature state of the container main body 10 that has been cooled due to the hydrogen gas release is maintained. Can be stored very efficiently.

  In addition, it is preferable that the cold insulation chamber 30A in the above embodiment is made of a material having a rigidity equal to or lower than the rigidity of the container body 10 to allow deformation of the container body 10 due to heating and cooling. Further, by providing the cold insulation chamber 30A as a buffer material, it is possible to eliminate the need for providing a buffer material separately. In the above embodiment, an example in which the cold insulation chamber 30 </ b> A is provided so as to cover the trunk portion 11 of the container main body 10 is shown, but a cold insulation chamber is provided so as to cover the dome portion 12 of the container main body 10. You can also. Further, a cold insulation chamber may be provided so as to cover the entire container body 10 (the trunk portion 11 and the dome portion 12). Moreover, in the above embodiment, although the example which supplied the cold insulating agent C from the downward direction of 30 A of cold storage chambers was shown, the cold insulating agent C can also be supplied from the upper side or side of the cold insulating agent 30A.

  In each of the above embodiments, an example in which the liner is made of a resin material has been shown, but the liner can also be made of a metal such as an aluminum alloy. In each of the above embodiments, an example in which a resin container body composed of a liner made of a resin material and a fiber reinforced resin layer is used has been shown, but a metal container body is employed. May be.

  In each of the above embodiments, the present invention is applied to a high-pressure tank that stores fuel gas for a fuel cell vehicle. However, the present invention is applied to a high-pressure tank that stores other gas such as natural gas. Can also be applied.

<Third Embodiment>
Next, a high pressure tank 1B according to a third embodiment of the present invention will be described with reference to FIGS. The high pressure tank 1B according to the present embodiment is provided with a heat storage material 60 at the gas filling / release port 20 instead of the cold insulation layer 30 provided so as to cover the container body 10 of the high pressure tank 1 according to the first embodiment. Other configurations are substantially the same as those of the first embodiment. For this reason, it demonstrates centering around the changed structure, and attaches | subjects the code | symbol same about the part which is common in 1st Embodiment, and abbreviate | omits the description.

  As shown in FIGS. 4 and 5, in the high-pressure tank 1 </ b> B according to this embodiment, a heat storage material 60 is enclosed in the gas filling / releasing port 20. The gas filling / releasing port 20 includes a tank boss 61 provided at the top of the dome portion 12 of the container main body 10 and a valve 70 fixed to the tip of the tank boss 61. The tank boss 61 is a substantially cylindrical member made of an aluminum alloy, and is fixed to the liner 11 such that a through-hole 62 having a circular cross section formed inside is aligned with the longitudinal direction of the container body 10.

  On the inner surface of the through-hole 62, a female screw portion 63 that is screwed with a male screw portion 71 of a valve 70 described later is formed. Further, around the tank boss 61, a flange portion 64 that is smoothly continuous with the outer surface of the liner 11 is formed. The tank boss 61 is fixed to the container body 10 by joining the lower surface of the flange portion 64 (the surface facing the inside of the container body 10) and the liner 11. As the material of the tank boss 61, a material other than an aluminum alloy can be used as long as it can withstand a sudden temperature change.

  The valve 70 is a member made of an aluminum alloy, like the tank boss 61, and has the male screw portion 71 described above and a head portion 72 formed at the base end of the male screw portion 71. The valve 70 is provided with a valve (not shown) for filling and releasing hydrogen gas. Further, an endless groove 73 is formed along the circumferential direction on the side surface on the distal end side of the male screw portion 71. An O-ring 74 that seals between the through hole 62 and the male screw portion 71 is disposed in the groove portion 73. The O-ring 74 is made of a fluorine rubber material.

  The valve 70 is fixed to the front end of the tank boss 61 by fitting the O-ring 74 into the groove 73 and inserting the male screw 71 into the through-hole 62 and screwing it into the female screw 63. In a state where the valve 70 is fixed to the front end of the tank boss 61, the front end surface of the tank boss 61 and the lower surface of the head 72 of the valve 70 (surface on the male screw portion 63 side) are in contact with each other without a gap.

  A material other than an aluminum alloy can be used as the material of the valve 70 as long as it can withstand a sudden temperature change. Similarly, any material other than a fluorine-based rubber material can be used for the O-ring 74 as long as it can withstand a sudden temperature change.

  A plurality of bottomed holes 65 are formed in the tank boss 61 in the same direction as the direction in which the through hole 62 extends. The plurality of holes 65 are arranged around the through hole 62 so that the adjacent holes 65 are spaced at equal intervals. On the inner surface of the hole 65, a female screw portion 66 that is screwed with a male screw portion 81 of the lid member 80 described later is formed at a position close to the opening. Further, an enlarged diameter portion 67 for accommodating the head portion 82 of the lid member 80 is formed in the opening portion of each hole 65.

  Further, an endless groove 68 is formed on the bottom surface of the enlarged diameter portion 67. An O-ring 69 that seals between the hole 65 and the male screw portion 81 is disposed in the groove portion 68. The inner diameter of the groove portion 68 is smaller than the diameter of the enlarged diameter portion 67, and the enlarged diameter portion 67 and the groove portion 68 form a step at the opening of the hole 65.

  Each hole 65 is provided with a lid member 80 that defines a closed space S1 inside the hole 65 by closing the opening of each hole 65. The lid member 80 is a metal member of the same kind or different kind from the tank boss 61, and has the male screw portion 81 described above and a head portion 82 formed at the base end of the male screw portion 81. Although not shown in the drawings, the head 82 of the lid member 80 is formed with a split groove for engaging the fastener or a hole with a polygonal cross section to fasten the lid member 80 to the hole 65.

  The lid member 80 is fastened to the hole 65 by the O-ring 69 being fitted to the base end of the male screw portion 81, the male screw portion 81 being inserted into the hole 65, and screwing with the female screw portion 66. The The hole 65 whose opening is closed by the lid member 80 is filled with the above-described heat storage material 60 in advance. In a state where the lid member 80 closes the hole 65, the bottom surface of the enlarged diameter portion 67 and the lower surface of the lid member 80 (surface on the male screw portion 81 side) are in contact with each other without a gap. Further, in this state, the front end surface of the tank boss 61 and the upper surface of the head portion 82 of the lid member 80 are matched to form a flat surface.

  One bottomed hole 75 is formed in the valve 70 so as to pierce the male screw portion 71 along the axis. On the inner surface of the hole 75, a female screw portion 76 that is screwed with a male screw portion 91 of a lid member 90 described later is formed at a position close to the opening.

  The hole 75 is provided with a lid member 90 that defines a closed space S <b> 2 inside the hole 75 by closing the hole 75. The lid member 90 is made of the same or different kind of metal as the valve 70, and has the male screw portion 91 described above and a head portion 92 formed at the base end of the male screw portion 91. An endless groove 93 is formed on the lower surface of the head 92 (the surface on the male screw portion 91 side). An O-ring 94 that seals between the hole 75 and the male screw portion 91 is disposed in the groove portion 93.

  The lid member 90 has the O-ring 94 applied to the lower surface of the head 92, and the male screw portion 91 is inserted into the hole 75 and is screwed into the female screw portion 76 to be fastened to the hole 75. . The hole 75 whose opening is closed by the lid member 90 is pre-filled with the heat storage material 60 in the same manner as the hole 65. In a state where the lid member 90 closes the hole 75, the upper surface of the valve 70 (the top surface of the head 72) and the lower surface of the lid member 90 (the surface on the male screw portion 91 side) are in contact with each other without a gap.

  For the heat storage material 60, for example, a 50 percent aqueous solution of ethylene glycol is used. The heat storage material 60 is a so-called latent heat storage material, and stores the heat by the release of thermal energy caused by the phase change from the gas phase to the liquid phase of the hydrogen gas stored in the high-pressure tank 1B. The supercooling due to the absorption of heat energy that occurs with the phase change from the liquid phase to the gas phase is suppressed by the heat stored when the heat energy is released.

  On the other hand, the heat storage material 60 stores cold energy by absorption of thermal energy caused by the phase change of the hydrogen gas stored in the high-pressure tank 1B from the liquid phase to the gas phase, and changes from the gas phase of the hydrogen gas to the liquid phase. Overheating due to the release of thermal energy that occurs with the phase change of is suppressed by the cold energy stored when the thermal energy is absorbed. As the heat storage material 60, a material whose components are adjusted so as to solidify in a temperature range in which the sealing performance is not impaired in consideration of the material of the O-ring 74 is used.

  Further, the amount of the heat storage material 60 enclosed is determined so as to maintain a temperature range in which the sealing performance is not impaired by the solidification of the heat storage material 60 in consideration of the temperature drop of the O-ring 74 when the tank is used. The heat storage material 60 can be the one used for the cold insulation layer of the first embodiment other than the 50% ethylene glycol aqueous solution.

  In the high-pressure tank 1B according to the embodiment described above, when the hydrogen gas is filled, the temperature in the high-pressure tank 1B rapidly increases as the hydrogen gas is compressed. That is, as the hydrogen gas changes from the gas phase to the liquid phase, the hydrogen gas releases thermal energy. When the hydrogen gas releases thermal energy, the heat storage material 60 enclosed in the gas filling / release port 20 is heated. The heat storage material 60 stores warm heat by being heated.

  When releasing hydrogen gas, the temperature in the high-pressure tank 1B rapidly decreases as the hydrogen gas expands. That is, as the hydrogen gas changes from the liquid phase to the gas phase, the hydrogen gas absorbs thermal energy. The high pressure tank 1B is supercooled by the hydrogen gas absorbing heat energy. The supercooling occurs most prominently in the vicinity of the gas filling / releasing port 20 where hydrogen gas rapidly expands.

  However, since the gas filling / releasing port 20 contains a heat storage material 60 that stores heat when hydrogen gas is filled, the supercooling of the high-pressure tank 1B is somewhat relaxed. That is, when hydrogen gas is released, heat exchange is performed between the gas filling / releasing port 20 and the heat storage material 60, whereby the gas filling / releasing port 20 is heated while the heat storage material 60 is cooled. The The heat storage material 60 stores cold energy by being cooled (cooled and solidified).

  FIG. 6 shows changes with time in the internal pressure of the high-pressure tank 1B and the temperature of the O-ring 74 when hydrogen gas is released. When the release of hydrogen gas is started, the internal pressure of the high-pressure tank 1B begins to decrease and decreases monotonically with the passage of time. Since the temperature of the O-ring 74 is cooled as the hydrogen gas changes from the liquid phase to the gas phase, it also decreases with the passage of time. However, since heat is stored in the heat storage material 60 at the time of the previous hydrogen gas filling, the temperature reduction of the O-ring 74 is suppressed without being continued as indicated by a two-dot chain line.

  When the temperature of the O-ring 74 falls below the freezing point temperature of the heat storage material 60, the temperature decrease of the O-ring 74 is close to the freezing point temperature of the heat storage material 60 depending on the predetermined component characteristics of the heat storage material 60 and the enclosed amount. Is suppressed. Thereafter, the O-ring 74 is kept substantially constant until the release of hydrogen gas is completed.

  Next, when hydrogen gas is charged, as the hydrogen gas changes from the gas phase to the liquid phase, the hydrogen gas releases thermal energy as before. The high-pressure tank 1B is overheated when the hydrogen gas releases thermal energy. However, since the heat storage material 60 that stores cold energy is enclosed in the gas filling / release port 20 when hydrogen gas is released, the overheating of the high-pressure tank 1B is somewhat relaxed.

  As described above, according to the high-pressure tank 1B of the present embodiment, it is possible to effectively suppress overcooling of the tank that occurs when hydrogen gas is released and overheating of the tank when hydrogen gas is charged. For example, in winter or cold districts where the temperature is low, the temperature of the O-ring 74 becomes stronger by releasing hydrogen gas even though the temperature of the high-pressure tank 1B is normally low. However, it is possible to effectively suppress overcooling of the tank.

  By the way, in this embodiment, when releasing hydrogen gas, the temperature decrease of the O-ring 74 is suppressed by the heat stored in the heat storage material 60 before that, and before filling with hydrogen gas, The component characteristics and the amount of the heat storage material 60 are determined in advance so that the overheating of the tank is suppressed by the cold heat stored in the heat storage material 60, but it is necessary to give the heat storage material 60 two functions in this way. There is no.

  The heat storage material 60 may only be given a function of suppressing a temperature drop of the O-ring 74 at least when releasing hydrogen gas. Further, in the present embodiment, the heat storage material 60 is provided in the gas filling / release port 20, but the heat storage material 60 may be provided in the container body 10.

It is a side view of the high-pressure tank concerning a 1st embodiment of the present invention. It is a side view which shows the modification of the high pressure tank which concerns on 1st Embodiment of this invention. It is a side view of the high-pressure tank concerning a 2nd embodiment of the present invention. It is sectional drawing which shows the structure of the gas filling and discharge port of the high pressure tank which concerns on 3rd Embodiment of this invention, and its periphery. FIG. 5 is an exploded view of the gas filling / releasing port shown in FIG. 4. It is a graph which shows the change with progress of time of the internal pressure of a high-pressure tank at the time of releasing the hydrogen gas stored in the high-pressure tank concerning a 3rd embodiment of the present invention, and the temperature of an O ring.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1A ... High pressure tank, 10 ... Container main body, 11 ... Trunk part (a part of container main body), 12 ... Dome part (a part of container main body), 20 ... Gas filling / release port, 21 ... Base, 30 ... Cold insulation layer, 30A ... cold insulation chamber, 40 ... cold insulation layer, 50 ... cold insulation layer, 60 ... heat storage material, 61 ... tank boss, 70 ... valve, C ... cold insulation agent

Claims (15)

  A high-pressure tank for storing gas, comprising a heat storage material.   The heat storage material stores heat by releasing heat energy that accompanies the phase change of the gas stored in the high-pressure tank, and is supercooled by absorption of heat energy that accompanies the phase change opposite to the phase change. The high-pressure tank according to claim 1, wherein the high-pressure tank is a latent heat storage material that suppresses heat by the heat stored when the thermal energy is released.   The heat storage material stores cold energy by absorbing thermal energy that accompanies the phase change of the gas stored in the high-pressure tank, and overheats due to the release of thermal energy that accompanies the phase change opposite to the phase change. The high-pressure tank according to claim 1, wherein the high-pressure tank is a latent heat storage material that is suppressed by cold energy stored when the thermal energy is absorbed.   A container body for storing the gas; and a base attached to the container body for filling the container body with the gas or discharging the gas from the container body, wherein the heat storage material is attached to the base. The high-pressure tank according to claim 1 or 2 provided.   A container body that stores the gas; and a base that is attached to the container body and fills the container body with the gas or discharges the gas from the container body, and the heat storage material includes the container body. The high-pressure tank according to claim 1 or 2, wherein the high-pressure tank is provided in at least a part of the tank. A high-pressure tank comprising a container body for storing gas,
A high-pressure tank comprising a cold insulation layer provided to cover at least a part of the container body.   The high pressure tank according to claim 6, wherein the cold insulation layer has a rigidity equal to or lower than a rigidity of the container body.   The high-pressure tank according to claim 6 or 7, wherein the cold insulation layer has a buffer function for protecting the container body from an external impact. A high-pressure tank comprising a container body for storing gas,
A high-pressure tank provided with a cold insulation chamber provided so as to cover at least a part of the container main body and filled with a predetermined cold insulation agent.   The high-pressure tank according to claim 9, wherein a predetermined cold-retaining agent is supplied to the cold-reserving chamber after gas is released from the container main body.   The high-pressure tank according to claim 9 or 10, wherein a predetermined cold-retaining agent is supplied to the cold-reserving chamber after the container body is filled with gas.   The high-pressure tank according to any one of claims 9 to 11, wherein the cold insulation chamber has a rigidity equal to or lower than a rigidity of the container body.   The high pressure tank according to any one of claims 9 to 12, wherein the cold insulation chamber has a buffer function for protecting the container body from an external impact.   14. The container body according to claim 6, comprising an inner layer made of a resin material and in direct contact with a gas, and an outer layer made of a fiber-reinforced resin material and provided outside the inner layer. High pressure tank. The high-pressure tank according to any one of claims 6 to 14, wherein the gas is high-pressure hydrogen gas and is mounted on a fuel cell vehicle.

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