KR102317404B1 - Hydrogen storage system and operation method thereof - Google Patents

Abstract

The present invention relates to a hydrogen storage system and a method for operating the same. More particularly, the present invention relates to a hydrogen storage system capable of stably supplying a sufficient amount of hydrogen required for starting a fuel cell, and a method for operating the same. According to the present invention, the hydrogen storage system comprises: a main storage unit in which hydrogen is supplied and a hydrogen storage alloy is built in; a sub storage unit communicating with the main storage unit to store hydrogen discharged from the main storage unit; and a heat and cooling medium circulation unit capable of storing hydrogen in the main storage unit or the sub storage unit by heating or cooling the main storage unit through heat or cooling medium.

Description

Hydrogen storage system and operation method thereof

The present invention relates to a hydrogen storage system and an operating method thereof, and more particularly, to a hydrogen storage system capable of stably supplying a sufficient amount of hydrogen required for starting a fuel cell and an operating method thereof.

As a storage method of hydrogen, there are a method of compressing and storing gaseous hydrogen, a method of storing it by liquefaction, and a storage method using a hydrogen storage alloy.

Among them, high compression energy is required to compress and store hydrogen gas, and the method of liquefying and storing hydrogen gas not only consumes a lot of energy, but also has a problem in that it is difficult to store for a long time due to loss of hydrogen gas during long-term storage. .

Due to the above problems, a method of storing hydrogen gas in a solid state in the form of a metal hydride using a hydrogen storage alloy, that is, a method of performing occlusion and release using a reversible hydrogenation/dehydrogenation reaction of a hydrogen storage alloy. and Korean Patent Registration No. 10-1052599 discloses a fuel cell vehicle having a hydrogen storage alloy container.

A fuel cell vehicle having such a hydrogen storage alloy container uses a hydrogen storage alloy container having a built-in hydrogen storage alloy as a fuel supply device for storing and supplying hydrogen fuel required for a fuel cell to generate electricity.

However, the hydrogen storage method using the hydrogen storage alloy does not properly supply a sufficient amount of hydrogen required at the time of starting the fuel cell, so that it cannot start or wait for a long time until sufficient hydrogen is supplied for starting. There is a problem that has to be done.

: Republic of Korea Patent No. 10-1052599

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hydrogen storage system capable of sufficiently providing hydrogen necessary for starting a fuel cell and a method for operating the same.

The hydrogen storage system according to the present invention includes a main storage unit in which hydrogen is supplied and a hydrogen storage alloy is embedded; a sub storage unit communicating with the main storage unit to store hydrogen discharged from the main storage unit; and a refrigerant circulation unit capable of storing hydrogen in the main storage unit or the sub storage unit by heating or cooling the main storage unit through a heat medium or a refrigerant.

In the hydrogen storage system according to an embodiment of the present invention, the refrigerant circulating unit stores the refrigerant and includes: a refrigerant tank connected to the main storage unit; a heat exchange unit for supplying a branched refrigerant from the refrigerant tank and exchanging the branched refrigerant; and a control unit for controlling the supply of refrigerant and heat medium to the main storage unit.

In the hydrogen storage system according to an embodiment of the present invention, the control unit may supply a refrigerant from the refrigerant tank to the main storage unit in the hydrogen storage mode, and supply heat from the heat exchange unit to the main storage unit in the hydrogen use mode.

In the hydrogen storage system according to an embodiment of the present invention, the hydrogen storage system may further include a fuel cell that receives hydrogen from a sub-storage unit and generates electric power.

In the hydrogen storage system according to an embodiment of the present invention, the refrigerant circulation unit may use waste heat generated in the fuel cell.

In the hydrogen storage system according to an embodiment of the present invention, a main valve for preventing reverse flow of hydrogen between the main storage unit and the sub storage unit may be further provided.

In the hydrogen storage system according to an embodiment of the present invention, the main storage unit includes a main tank for accommodating a refrigerant or heat medium therein, and a sub-tank built in the main tank and having a hydrogen storage alloy embedded therein, The storage alloy may form a main hydrogen flow path through which hydrogen may flow in the sub-tank.

In the hydrogen storage system according to an embodiment of the present invention, the main storage unit may further include a shape maintaining unit which is installed and inserted into the main hydrogen flow path to enable movement of hydrogen so as to maintain the shape of the main hydrogen flow path.

In the hydrogen storage system according to an embodiment of the present invention, the shape maintaining part extends along the extension direction of the main hydrogen flow path, both ends are open to form a sub-hydrogen flow path communicating with the main hydrogen flow path therein, at least on one side A side hydrogen transfer path capable of moving hydrogen from the hydrogen storage alloy may be formed.

In the hydrogen storage system according to an embodiment of the present invention, the shape maintaining unit may include a spiral tube extending in a spiral direction along the inner surface of the main water passage.

In the hydrogen storage system according to an embodiment of the present invention, the shape maintaining unit may be provided with a mesh pipe manufactured by braiding or woven.

In the hydrogen storage system according to an embodiment of the present invention, the main storage unit may further include a support member installed in the sub-hydrogen flow path of the shape maintaining unit to support the shape maintaining unit and to allow the flow of hydrogen.

In the hydrogen storage system according to an embodiment of the present invention, the support member extends from the inside of the sub-hydrogen flow path to the sub-hydrogen flow path, and forms an internal space with both ends open, and at least one perforated hole communicating with the internal space. This formed perforated tube may be provided.

In the present invention, hydrogen is supplied, and the main storage unit in which the hydrogen storage alloy is embedded, the main storage unit communicates with the main storage unit and stores hydrogen discharged from the main storage unit, and the main storage unit is heated or cooled through heat or refrigerant. An operating method of a hydrogen storage system including a refrigerant circulation unit capable of storing hydrogen in a main storage unit or a sub storage unit, (A) supplying a refrigerant to the main storage unit and converting the hydrogen supplied to the main storage unit to a hydrogen storage alloy occluding; and, when hydrogen is supplied to the main storage unit, hydrogen is simultaneously supplied to the sub storage unit.

In the operating method according to an embodiment of the present invention, the hydrogen storage system further includes a fuel cell for generating electricity by receiving hydrogen, and after step (A), (B1) hydrogen is supplied from the sub-storage unit to the fuel cell. supplying the fuel cell to operate; (B2) generating heat by heat-exchanging waste heat generated by the operation of the fuel cell with a refrigerant; (B3) supplying heat to the main storage unit and supplying hydrogen released as the main storage unit is heated to the sub storage unit; Hydrogen can be supplied to the fuel cell by repeating steps (B1) to (B3) one or more times as a unit process.

In an operating method according to an embodiment of the present invention, when the operation of the fuel cell is terminated, (C1) stopping the supply of hydrogen from the sub-storage unit to the fuel cell; (C2) generating heat from residual heat in the fuel cell and heat exchange with the refrigerant; (C3) supplying the fruit to the main storage unit and storing the hydrogen released as the main storage unit is heated in the sub storage unit.

In the hydrogen storage system according to an embodiment of the present invention, the hydrogen storage alloy may be mixed with a thermally conductive material and contained in the hydrogen storage complex.

In the hydrogen storage system according to an embodiment of the present invention, the hydrogen storage complex may further contain a resin.

In the hydrogen storage system according to an embodiment of the present invention, the hydrogen storage complex may contain 0.5 to 70 parts by weight of the thermal conductive material and 1 to 70 parts by weight of the resin based on 100 parts by weight of the hydrogen storage alloy.

In the hydrogen storage system according to an embodiment of the present invention, the hydrogen storage complex comprises the steps of (D1) mixing a thermally conductive material and a resin to obtain a first mixture; (D2) mixing a hydrogen storage alloy with the first mixture to obtain a second mixture; And (D3) forming the second mixture; can be prepared from.

In the hydrogen storage system according to an embodiment of the present invention, the hydrogen storage complex may be manufactured from (D3) and then, (D4) a curing step of curing the molded second mixture.

The hydrogen storage system and the method for operating the same according to the present invention can store and supply a sufficient amount of hydrogen necessary for starting the fuel cell in a separately provided sub-storage unit, thereby increasing the stability of starting the fuel cell.

In addition, it is possible to cool or heat the hydrogen storage alloy through the refrigerant or heat medium, so that hydrogen can be stored and supplied quickly as needed.

In addition, as hydrogen occlusion and release of the hydrogen storage alloy is made through the refrigerant or heat medium, the charging pressure and the releasing pressure of hydrogen are constant, so that the pressure of hydrogen supplied to the fuel cell can be maintained constant.

1 is a view showing the configuration of a hydrogen storage system of the present invention according to a first embodiment;
2 is a sectional view A-A' of the main tank of the hydrogen storage system shown in FIG. 1;
3 is a partially cut-away perspective view of the sub tank according to the second embodiment;
4 is a partially cut-away perspective view of a sub-tank according to a third embodiment;
5 is a partially cut-away perspective view of a sub-tank according to the fourth embodiment;
6 is a partially cut-away perspective view of a sub tank according to the fifth embodiment;
7 is a partially cut-away perspective view of a sub-tank according to the sixth embodiment;
8 is a partially cut-away perspective view of a sub-tank according to the seventh embodiment;
9 is a graph showing the pressure-composition isotherm of the hydrogen storage complex of the present invention;
10 is a graph showing the amount of hydrogen storage per hour of the hydrogen storage complex according to FIG. 9;
11 is a photograph of the hydrogen storage complex according to FIG.

Unless otherwise defined in technical terms and scientific terms used in this specification, those of ordinary skill in the art to which this invention belongs have the meanings commonly understood, and in the following description and accompanying drawings, the subject matter of the present invention Descriptions of known functions and configurations that may unnecessarily obscure will be omitted.

Also, the singular form used herein may be intended to include the plural form as well, unless the context specifically dictates otherwise.

In addition, in the present specification, the unit used without special mention is based on the weight, for example, the unit of % or ratio means weight % or weight ratio, and unless otherwise defined, the weight % is any one component of the entire composition. It means % by weight in the composition.

In addition, the numerical range used herein includes the lower limit and upper limit and all values within the range, increments logically derived from the form and width of the defined range, all values defined therein, and the upper limit of the numerical range defined in different forms. and all possible combinations of lower limits. Unless otherwise defined in the specification of the present invention, values outside the numerical range that may occur due to experimental errors or rounding of values are also included in the defined numerical range.

As used herein, the term 'comprising' is an open-ended description having an equivalent meaning to expressions such as 'comprising', 'containing', 'having' or 'characterized', and elements not listed further; Materials or processes are not excluded.

In addition, as used herein, the term 'substantially' means that other elements, materials, or processes not listed together with the specified element, material or process are unacceptable for at least one basic and novel technical idea of the invention. It means that it can be present in an amount or degree that does not significantly affect it.

Unless otherwise defined herein, the flat pressure section within the pressure-composition isotherm of the hydrogen storage alloy corresponds to a stable region in which the pressure does not change significantly as the amount of hydrogen gas occluded by the hydrogen storage alloy increases. means range.

Hereinafter, a hydrogen storage system according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the hydrogen storage system of the present invention, hydrogen is supplied, the main storage unit having a hydrogen storage alloy embedded therein, the sub storage unit communicating with the main storage unit to store hydrogen discharged from the main storage unit, and main storage through the medium or refrigerant and a cooling fruit circulation unit capable of storing hydrogen in the main storage unit or the sub storage unit by heating or cooling the unit.

In the case of a hydrogen storage system using a conventional hydrogen storage alloy, when hydrogen is supplied to a power device that uses hydrogen as a fuel, such as a fuel cell, the amount of hydrogen required at the time of starting the power device cannot be sufficiently supplied. There is a problem in that it waits for a long time until the necessary hydrogen is sufficiently supplied. In particular, it occurs more frequently when the ambient temperature is low, such as in winter, and in severe cases, the start was not performed.

The hydrogen storage system of the present invention is provided with a sub-storage unit capable of storing hydrogen separately from the main storage unit in which the hydrogen storage alloy is embedded. Hydrogen required for starting an electric power device using hydrogen as a fuel, such as a fuel cell, may be stored in the sub storage unit. As hydrogen is stored in the sub-storage unit separately from the hydrogen storage alloy, hydrogen required for starting a power generation device using hydrogen as a fuel, such as a fuel cell, can be stably supplied. In detail, in the sub storage unit, hydrogen may be stored by an external hydrogen supply device such as a hydrogen charger or a main storage unit inside the hydrogen storage system. For example, when hydrogen is charged in the main storage unit by a hydrogen supply device such as a hydrogen charger, the sub storage unit may also be charged with hydrogen by the hydrogen charger. On the other hand, heat is supplied to the main storage unit by the cooling medium circulation unit, and hydrogen emitted as the main storage unit is heated may be stored in the sub storage unit. A main valve provided as a backflow prevention valve is installed between the main storage unit and the sub storage unit, so that hydrogen can be stored in the sub storage unit without a separate control process and power supply.

And the hydrogen storage system of the present invention is provided with a cooling medium circulation unit capable of cooling and heating the main storage unit by supplying refrigerant and heat to the main storage unit. In detail, when the refrigerant circulation unit supplies the refrigerant to the main storage unit, hydrogen occlusion occurs in the hydrogen storage alloy provided in the main storage unit and hydrogen is stored, and when the refrigerant is supplied to the main storage unit, hydrogen provided in the main storage unit Hydrogen is released from the storage alloy. In this way, hydrogen can be stored or released through the refrigerant or heat medium, so that the occlusion and release of hydrogen can be performed quickly. That is, the hydrogen charging speed of the main storage unit is increased, and hydrogen is rapidly released from the main storage unit, so that hydrogen can be used without waiting time.

In addition, the refrigerant circulation unit can cool or heat the hydrogen storage alloy of the main storage unit at a constant temperature of the refrigerant or heat medium regardless of the ambient temperature, thereby maintaining a constant pressure of charged and discharged hydrogen. For example, when the hydrogen storage system of the present invention is applied to a power generation device using hydrogen as a fuel, such as a fuel cell, a more stable operation of the power generation device can be achieved because hydrogen at a constant pressure can be provided to the power generation device. let it be

The refrigerant circulation unit may include a refrigerant tank in which the refrigerant is stored, a heat exchange unit capable of converting the refrigerant branched from the refrigerant tank into a heat medium, and a control unit for controlling the supply of the refrigerant and the heat medium, and the control unit includes a hydrogen storage mode, hydrogen Depending on the mode of use, the refrigerant or heat supplied to the main storage unit can be controlled. In detail, the control unit supplies the refrigerant to the main storage unit in the hydrogen storage mode, and supplies the heat medium to the main storage unit in the hydrogen use mode. The refrigerant tank of the hydrogen refrigerant circulation unit may be connected to the main storage unit by a connecting member such as a coupler, and may be connected to the main storage unit if necessary. In detail, in the hydrogen storage mode of the control unit, the refrigerant may be supplied to the main storage unit by being connected to the main storage unit. On the other hand, in the hydrogen use mode of the control unit, the connection with the main storage unit may be disconnected and separated. The heat exchange unit converts the refrigerant into a heat medium, and as a heat source, waste heat of a fuel cell, which will be described later, can be used. Accordingly, it is possible to provide a system with higher energy efficiency.

Such a hydrogen storage system of the present invention may be installed as a hydrogen supply source of a fuel cell. The hydrogen storage system of the present invention has very high energy efficiency because it converts the refrigerant into heat using only the waste heat of the fuel cell, and it is more compact as it can be connected to an external hydrogen supply device and a refrigerant tank only when necessary. Since it can be provided in one structure, it can be suitable for a fuel cell vehicle.

In the fuel cell vehicle equipped with the hydrogen storage system of the present invention, since a sufficient amount of hydrogen is stored in the sub-storage unit, hydrogen required for starting the fuel cell vehicle can be stably supplied. In addition, since hydrogen occlusion and discharge of the main storage unit is made by the refrigerant circulation unit, hydrogen can be provided at a constant pressure regardless of the season and the surrounding environment, so that the vehicle can be driven stably. In addition, such a vehicle can provide convenience to the user by increasing the charging and discharging rates of hydrogen.

1 to 2 show a hydrogen storage system according to a first embodiment of the present invention.

1 to 2, the hydrogen storage system according to the present invention is supplied with hydrogen and includes a main storage unit 10 in which a hydrogen storage alloy 15 is embedded.

The main storage unit 10 may store hydrogen supplied from the hydrogen supply device 21 such as a hydrogen charger or a hydrogen cylinder. At this time, the hydrogen supply device 21 may be installed outside the main storage unit 10 separately, and may be connected to the main storage unit 10 as needed by a first connecting member 21a such as a coupler. . That is, when hydrogen is charged into the main storage unit 10 , the hydrogen supply device 21 may be connected to supply hydrogen to the main storage unit 10 . The main storage unit 10 is connected to the hydrogen supply unit 21 and the sub storage unit 30 to be described later to store the hydrogen supplied from the hydrogen supply unit 21 and then supply hydrogen to the sub storage unit 30 . have. In addition, it may be connected to the cooling medium circulation unit 50 to be described later and heated or cooled by a refrigerant or a medium. The main storage unit 10 may include a main tank 11 for accommodating heat or heat inside, and a sub-tank 13 built in the inside of the main tank 11 and having a hydrogen storage alloy 15 built therein. .

The main tank 11 is a tubular member that forms an inner space of a square cross section, and a plurality of sub tanks 13 having a hydrogen storage alloy 15 built therein may be embedded therein. A refrigerant or heat medium may be accommodated in the inner space of the main tank 11 , and the sub-tank 13 may be heated or cooled within the main tank 11 by the received refrigerant or heat medium. The main tank 11 may be a cylindrical member having a polygonal cross-section, such as a circle or a triangular and pentagonal cross section, unlike shown in the drawings, and to accommodate the sub tank 13 and the refrigerant and the heat medium therein. Any shape forming the inner space 12 may be applicable.

The sub tank 13 is a tubular member having a smaller diameter than the main tank 11 , forms a longitudinal direction parallel to the longitudinal direction of the main tank 11 , and may be installed inside the main tank 11 . The sub-tank 13 may be a tank in which the existing hydrogen storage alloy 15 is stored, and may be a cylindrical member having a polygonal cross-section, unlike shown in the drawings. A plurality of sub tanks 13 may be provided inside the main tank 11 . Both ends of the plurality of sub tanks 13 may be in communication with each other, one end of which is connected to the hydrogen supply device 21 so that hydrogen is supplied therein, and the other end is connected to the sub storage unit 30 to store the sub. Hydrogen may be supplied to the part 30 side. It may be preferable that the plurality of sub-tanks 13 are spaced apart from each other at the same interval inside the main tank 11 and arranged. Accordingly, the refrigerant or heat medium flowing in the main tank 11 may uniformly contact the outer surface of the sub-tank 13 . Accordingly, the occlusion and release of hydrogen by the refrigerant or heat medium is uniformly performed, and hydrogen can be supplied to the sub storage unit 30 at a more uniform pressure.

The hydrogen storage alloy 15 built into the sub-tank 13 may form a main hydrogen flow path 14 through which hydrogen can flow in the sub-tank 13 . The hydrogen storage alloy 15 may refer to an alloy having a property of occluding hydrogen in a specific pressure and temperature range to form a metal hydride, and releasing hydrogen again by a change in pressure and temperature. The hydrogen storage alloy 15 has a hollow disk shape and may be formed in various thicknesses. The hydrogen storage alloy 15 may be stacked so that hollows in the sub-tank 13 pass through each other. Hydrogen introduced into the sub-tank 13 may flow through the hollow of the hydrogen storage alloy 15 . That is, the main hydrogen passage 14 may be formed where the hollow of the hydrogen storage alloy 15 is located.

The hydrogen storage alloy 15 is _{at least one selected from the group consisting of AB 5} type, AB ₂ type, AB type, and A ₂ B type, wherein A is lanthanum (La), zirconium (Zr), titanium (Ti) , calcium (Ca) and magnesium (Mg), wherein B is nickel (Ni), copper (Cu), zinc (Zn), iron (Fe), cobalt (Co), manganese (Mn), vanadium (V ) can be one of As a specific example, LaNi ₅ , CaCu ₅ , TiMn _{2 ,} ZrNi ₂ , It may be one or more selected from TiFe, TiCo, Mg ₂ Ni, and Mg ₂ Cu, but is not limited thereto.

The sub-storage unit 30 connected to the main storage unit 10 is a container capable of storing hydrogen, and its shape is not limited. The sub storage unit 30 may store hydrogen discharged by the hydrogen supply device 21 or the main storage unit 10 . The sub-storage unit 30 may store an amount of hydrogen greater than the amount of hydrogen discharged from the hydrogen storage alloy. The sub-storage unit 30 may provide sufficient hydrogen necessary for starting the fuel cell 70 , which will be described later. The sub-storage unit 30 continuously maintains the fuel cell until the temperature of the fruit, which will be described later, is heated to a temperature of 40 to 90°C, preferably 60 to 80°C, due to waste heat generated as the fuel cell, which will be described later, is operated. Sufficient amounts of hydrogen to start and run can be stored.

A main valve 35 for preventing the reverse flow of hydrogen may be installed between the main storage unit 10 and the sub storage unit 30 . As the main valve 35, any valve capable of blocking or opening the flow of hydrogen is applicable, but preferably a non-return valve may be used. The non-return valve operates only when hydrogen flows from a high pressure to a low pressure due to the differential pressure without a separate control process and power supply. In addition, the degree of opening of the non-return valve may vary according to the magnitude of the differential pressure, and the greater the differential pressure, the greater the degree of opening may increase the flow rate of hydrogen.

Specifically, the non-return valve may have a cracking pressure of 1 to 15, preferably 1 to 8 bar, which is the minimum upstream pressure at which the valve operates, but is not limited thereto. When the main valve 35 is a non-return valve, when hydrogen flows into the sub-storage unit 30 from the main storage unit 10, when the differential pressure becomes 0 or less, the main valve 35 is automatically closed, Backflow problems may not occur.

For example, the hydrogen storage system according to the present invention may further include a fuel cell 70 that receives hydrogen from the sub-storage unit 30 and generates electric power.

The fuel cell 70 connected to the sub-storage unit 30 and capable of receiving hydrogen from the sub-storage unit 30 may generate electric power based on hydrogen energy. A sub-valve 37 that can be opened and closed by the control unit may be installed between the fuel cell 70 and the sub-storage unit 30 .

The fuel cell 70 may include a body 71 (a stack) and a refrigerant circulation unit 75 . The body 71 generates electric power through hydrogen, and at this time, heat (waste heat) is generated and the body 71 needs to be cooled as the temperature of the body 71 increases. The refrigerant circulation unit 75 may supply the first refrigerant to the main body 71 to cool the main body 71 . The refrigerant circulation unit 75 is connected to the main body 71 and a heat exchange unit 55 to be described later to circulate, a circulation line 77 through which the first refrigerant or first fruit flows, and air cooling installed in the circulation line 77 . A fan 78 and a pump 79 may be provided. On the other hand, the refrigerant circulation unit 75 is a conventional refrigerant circulation structure capable of cooling the main body 71 is applicable. The first refrigerant supplied to the main body 71 by the refrigerant circulation unit 75 may absorb waste heat of the main body 71 and be converted into a first fruit. The first refrigerant converted into the first refrigerant may be converted back to the first refrigerant while passing through a heat exchange unit 55 to be described later. The first refrigerant passing through the heat exchange unit 55 may be further cooled by the air cooling fan 78 . Of course, since a separate regulator 39 is installed between the sub-storage unit 30 and the fuel cell 70 , hydrogen supplied from the sub-storage unit 30 to the fuel cell 70 may be reduced in pressure.

The cooling medium circulation unit 50 may supply a refrigerant or heat medium to the main storage unit 10 to cool or heat the main storage unit 10 . The cooling medium circulation unit 50 supplies heat to the main storage unit 10 to heat the sub-tank 13 built into the main tank 11 so that hydrogen can be released from the hydrogen storage alloy 15 . do. On the other hand, the cold refrigerant circulation unit 50 supplies the refrigerant to the main storage unit 10 to cool the sub-tank 13 so that the hydrogen storage alloy 15 occludes hydrogen, that is, hydrogen can be charged.

The refrigerant circulation unit 50 stores the refrigerant, and the refrigerant is branched and supplied from the refrigerant tank 51 and the refrigerant tank 51 connected to the main tank 11 of the main storage unit 10, and the branched refrigerant is supplied. It may include a heat exchange unit 55 for heat exchange, and a control unit (not shown) for controlling the supply of refrigerant and heat to the main storage unit 10 . The refrigerant circulation unit 50 may convert the refrigerant into a heat medium only with waste heat generated in the fuel cell 70 without using a separate energy as a heat source. Such a structure does not require additional energy, so it has excellent energy efficiency and can significantly reduce costs due to energy consumption.

The refrigerant tank 51 is a container in which a refrigerant such as cooling water is accommodated. The refrigerant tank 51 may be integrally connected to the hydrogen storage system, but unlike the hydrogen storage system, it is installed separately, and is connected to the hydrogen storage system by a connecting member such as a coupler, and may be connected as needed. The refrigerant tank 51 may include a supply coupler 51b for supplying the refrigerant to the main storage unit 10 and an accommodation coupler 51a for receiving the refrigerant or heat from the main storage unit 10 side, respectively.

As the refrigerant supplied to the outside of the refrigerant tank 51 through the supply coupler 51b is accommodated into the refrigerant tank 51 through the receiving coupler 51a, the refrigerant or heat medium may be circulated. An interconnected branch line 58 may be further installed between the supply coupler 51b and the receiving coupler 51a , and a valve 57 may be installed on the branch line 58 . When the valve 57 is closed, the refrigerant supplied from the refrigerant tank 51 to the main storage unit 10 through the supply coupler 51b passes through the main storage unit 10 and then through the receiving coupler 51a. It is accommodated in the refrigerant tank 51 again, and the refrigerant can be circulated. On the other hand, when the valve 57 is opened, the supply coupler 51b and the receiving coupler 51a are closed so that the refrigerant already supplied does not circulate through the refrigerant tank 51, and the heat exchange unit 55 and the main storage It can be circulated through the section 10 . The valve 57 can be adjusted by a control unit.

The heat exchange unit 55 heats the refrigerant branched from the refrigerant tank 51 and converts the refrigerant into a heat medium, and waste heat of the fuel cell 70 may be used. A conventional heat exchanger may be applied to the heat exchange unit 55 , and the refrigerant supplied from the refrigerant tank 51 and the first fruit supplied from the fuel cell 70 may be exchanged with each other. The refrigerant converted into heat in the heat exchange unit 55 may move to the main storage unit 10 to heat the main storage unit 10 . A pump 53 is disposed between the refrigerant tank 51 and the heat exchange unit 55 . can be installed to facilitate the circulation of fruits. The heat exchange unit 55 may be connected to the supply coupler 51b of the refrigerant tank 51 described above, and convert the refrigerant supplied through the supply coupler 51b into heat or the refrigerant as it is in the main storage unit 10 . can supply

The control unit may supply a refrigerant or heat medium to the main storage unit 10 according to a hydrogen storage mode or a hydrogen use mode. The control unit may supply refrigerant from the refrigerant tank 51 to the main storage unit 10 in the hydrogen storage mode, and may supply heat from the heat exchange unit 55 to the main storage unit 10 in the hydrogen use mode.

The hydrogen storage mode may be a mode for storing hydrogen in the main storage unit 10 and the sub storage unit 30 .

The control unit moves the refrigerant from the refrigerant tank 51 to the heat exchange unit 55 by operating the pump installed in the refrigerant circulation unit 50 so that the refrigerant can be supplied to the main storage unit 10 in the hydrogen storage mode. have. The refrigerant passing through the heat exchange unit 55 may move into the main tank 11 of the main storage unit 10 . At this time, the heat exchange unit 55 is in a state in which waste heat does not exist, and heat exchange does not occur. Accordingly, the refrigerant is supplied to the main storage unit 10 as it is without being converted into a heat medium, and the main storage unit 10 can be cooled.

In the hydrogen storage mode, the refrigerant tank 51 may be connected to the main storage unit 10 by the supply coupler 51b and the accommodation coupler 51a, and the hydrogen supply unit 21 is also the main storage unit by the coupler. (10) may be connected. The control unit closes the valve 57 in the hydrogen storage mode so that the refrigerant supplied from the refrigerant tank 51 to the main storage unit 10 through the supply coupler 51b is again supplied to the refrigerant tank 51 through the supply coupler 51b. ) may not be accepted.

In the hydrogen storage mode, hydrogen supplied from the hydrogen supply device 21 may be charged in the hydrogen storage alloy 15 inside the cooled main storage unit 10 . Hydrogen supplied from the hydrogen supply device 21 may be stored in the main storage unit 10 and at the same time stored in the sub storage unit 30 connected to the main storage unit 10 . The control unit may close the sub-valve 37 so that hydrogen is not supplied to the fuel cell 70 connected to the sub-storage unit 30 .

In contrast, the hydrogen use mode is a mode that uses stored hydrogen.

In the hydrogen use mode, the fuel cell 70 may be operated. The control unit may open the sub-valve 37 so that hydrogen is supplied to the fuel cell 70 connected to the sub-storage unit 30 . The hydrogen stored in the sub-storage unit 30 is supplied to the fuel cell 70 and the fuel cell 70 can be operated, and the hydrogen in the sub-storage unit 30 is supplied to the fuel cell 70 and the fuel cell A heat medium may be supplied to the heat exchange unit 55 by the waste heat generated in 70 . After operation (startup) and generation of waste heat of the fuel cell 70 are made by the hydrogen stored in the sub storage unit 30 , the heat generated by the waste heat of the fuel cell 70 is supplied to the main storage unit 10 , The hydrogen stored in the hydrogen storage alloy 15 is released, so that the operation of the fuel cell 70 can be maintained.

In the hydrogen use mode, the control unit may convert the supplied refrigerant into heat medium and circulate the main storage unit 10 and the heat exchange unit 55 . At this time, the main storage unit 10 is disconnected from the refrigerant tank 51 by the supply coupler 51b and the receiving coupler 51a connected to the refrigerant tank 51 , and the connection with the hydrogen supply device 21 is also canceled can be And the valve can be opened. The supplied refrigerant passes through the heat exchange unit 55 , and may be exchanged with waste heat generated according to the operation of the fuel cell 70 to be converted into a heat medium. The converted fruit passes through the main storage unit 10 and heats the main storage unit 10 so that the hydrogen stored in the hydrogen storage alloy 15 is released. The fruit passes through the main storage unit 10 and may be converted into a refrigerant. The converted refrigerant is again converted into a heat medium through the heat exchange unit 55 , is supplied to the main storage unit 10 , and circulates by repeating the above process. The controller may also adjust the amount of hydrogen provided to the fuel cell 70 by adjusting the sub-valve 37 in the hydrogen use mode.

When the operation of the fuel cell 70 is stopped after the hydrogen use mode, the controller may perform the sub-hydrogen storage mode. The sub-hydrogen storage mode may be automatically performed after the end of the hydrogen use mode. The sub-hydrogen storage mode is a mode for storing hydrogen again in the sub-storage unit 30, and by this sub-hydrogen storage mode, the main storage unit (10) Regardless, the fuel cell 70 may be driven by the sub storage unit 30 . In the sub-hydrogen storage mode, the control unit may block the sub-valve 37 . In addition, the refrigerant and the heat medium can be circulated so that the heat medium can be supplied to the main storage unit 10 in the same way as in the hydrogen use mode. Accordingly, hydrogen may be continuously supplied to the sub-storage unit 30 to store a sufficient amount of hydrogen in the sub-storage unit 30 . In this case, the heat exchange unit 55 may retain residual heat (residual waste heat) even when the operation of the fuel cell 70 is stopped, so that heat exchange may be possible. A sufficient amount of hydrogen stored in the sub-storage unit 30 can then be used when the fuel cell 70 is started again, so that the hydrogen storage system of the present invention can have a stable hydrogen supply power.

As such, the hydrogen storage system of the present invention includes a sub-storage unit separate from the main storage unit in which the hydrogen storage alloy is embedded, and thus can store a sufficient amount of hydrogen required for starting and operating the fuel cell. As the main storage unit can be heated or cooled by the refrigerant circulation unit, the rate of hydrogen charging and discharging of the main storage unit can be increased. In addition, heat exchange efficiency may be very good because the refrigerant is converted into a heat medium using only the waste heat of the fuel cell. And as the charging and discharging of hydrogen is made at the temperature of the refrigerant or the medium regardless of the ambient temperature, the pressure at which hydrogen is charged and the pressure at which the hydrogen is discharged can be kept constant.

In particular, the hydrogen storage system of the present invention may be suitable for a fuel cell vehicle. The hydrogen storage system of the present invention can be used by connecting couplers if necessary after the hydrogen supply device and the refrigerant tank are separately provided outside. In addition, since only waste heat of the fuel cell is used as a heat source, there is no need to install a separate heating device, and thus a simpler structure is provided. Accordingly, since it is relatively light and compact, it may be suitable for a fuel cell vehicle.

In addition, in the hydrogen storage system of the present invention, since the sub-storage unit can provide hydrogen necessary for starting the fuel cell vehicle, it is possible to prevent malfunction of starting. The charging speed is greatly increased, and a constant hydrogen pressure is provided to enable stable driving.

3 to 8 show the sub-tanks of the hydrogen storage system according to the second to seventh embodiments of the present invention.

According to another embodiment of the present invention, the main storage unit of the present invention may further include a shape maintaining unit 40 that is inserted and installed to allow movement of hydrogen into the main hydrogen flow path so as to maintain the shape of the main hydrogen flow path. .

The shape maintaining part 40 is preferably made of a metal material having high strength to withstand the pressure during expansion of the hydrogen storage alloy 15, but is not limited thereto. The shape maintaining part 40 may be a tubular member extending along the extension direction of the main hydrogen flow path 14 . Both ends of the shape maintaining unit 40 may be opened to form a sub-hydrogen channel 44 communicating with the main hydrogen channel 14 therein. The shape maintaining part 40 may be formed with a side hydrogen flow path 42 capable of moving hydrogen from the hydrogen storage alloy 15 on at least one side facing the inner surface of the hydrogen storage alloy 15 . Hydrogen may move to the hydrogen storage alloy 15 and the sub-hydrogen flow path 44 through the side hydrogen flow path 42 . Such a shape maintaining part 40 supports the hydrogen storage alloy 15 on the inner surface of the hydrogen storage alloy 15, and can prevent the hydrogen storage alloy 15 from collapsing, which is generated as hydrogen is occluded and released. have. Alternatively, even when the hydrogen storage alloy 15 is collapsed, the main hydrogen passage 14 can be stably secured by supporting the main hydrogen passage 14 to maintain the shape. The shape maintaining part 40 is inserted into the main hydrogen flow path 14 to support the inner surface of the hydrogen storage alloy 15, and the hydrogen movement of the main hydrogen flow path 14, the hydrogen storage alloy 15 and the main hydrogen flow path (14) Any structure that does not interfere with the hydrogen movement between them can be applied.

As shown in FIG. 3 , the shape maintaining unit 40 may be provided as a spiral tube 41 extending in a spiral direction along the inner surface of the main hydrogen flow path 14 . As shown in the drawing, the spiral tube may be provided with a rod member filled therein extending in a spiral direction. Alternatively, a tube member with an empty interior may be provided to extend in a spiral direction. As the spiral tube extends in the spiral direction, a spiral-shaped sub-hydrogen channel 44 may be formed.

Alternatively, the shape maintaining unit 40 may be provided as a mesh tube 47 manufactured by braiding or woven as shown in FIG. 4 . As the mesh tube is braided or woven, a plurality of through-hole-shaped sub-hydrogen channels 44 may be formed on the outer surface.

On the other hand, as shown in FIG. 5 , the shape maintaining part 40 may be provided in a plurality of overlapping pieces. Referring to FIG. 5 , a spiral tube 41 may be inserted into the mesh tube 47 inserted into the main hydrogen passage 14 . At this time, the spiral tube 41 may have a diameter that can be inserted into the mesh tube 47 . Alternatively, the mesh tube 47 may be provided by being inserted into the spiral tube 41, of course. In addition, unlike shown in the drawings, various shape maintaining units 40 having different diameters may be installed to overlap the main hydrogen flow path 14 . In this way, the shape maintaining unit 40 installed to be overlapped can more stably maintain the shape of the main hydrogen flow path 14 .

The main storage unit 10 provided with such a shape maintaining unit 40 can stably support the hydrogen storage alloy 15 built into the sub-tank 13, so that Collapse of the hydrogen storage alloy 15 can be prevented. In addition, even when the hydrogen storage alloy 15 is collapsed, the shape of the main hydrogen passage 14 is maintained so that hydrogen can move smoothly. Accordingly, it is possible to prevent malfunction due to the collapse of the hydrogen storage alloy 15, and it is possible to extend the life of the system.

In addition, as shown in FIGS. 6 to 7 , the shape maintaining unit 40 supports the shape maintaining unit 40 and allows the flow of hydrogen inside the sub-hydrogen flow path 44 of the shape maintaining unit 40 . A support member 60 to be installed may be further provided. The support member 60 is a rod or tubular member, and when inserted into the sub-hydrogen flow path 44 of the shape maintaining unit 40 , the outer surface of the support member 60 is completely aligned with the inner surface of the shape maintaining unit 40 . It may not interfere with the hydrogen movement of the sub-hydrogen flow path 44 by not being in close contact. As shown in FIG. 7 , the support member 60 may be provided by inserting a plurality of rod members 61 into the sub-hydrogen flow path 44 of the shape maintaining unit 40 . Alternatively, the support member may be a rod or a pipe member having a polygonal cross-section such as a triangle or a square.

As shown in FIG. 8 , the support member 60 is a tubular member extending from the inside of the sub-hydrogen channel 44 in the direction of the sub-hydrogen channel 44 and forming an inner space with both ends open. can At this time, the support member 60 may be a perforated pipe 63 in which a plurality of perforated holes 65 communicating with the inner space are formed. As the perforated hole 65 is formed, the support member 60 can support the shape maintaining part 40 and facilitate hydrogen movement between the hydrogen storage alloy 15 and the sub-hydrogen flow path 44 . A plurality of perforated pipes 63 may also be inserted and provided in the sub-hydrogen flow path 44 .

As such, the main storage unit 10 in which the support member 60 is installed can more stably support the hydrogen storage alloy 15 built in the sub-tank 13 . Accordingly, as the lifespan of the hydrogen storage alloy 15 is further extended, the lifespan of the hydrogen storage system of the present invention can also be further increased.

According to another embodiment of the present invention, the hydrogen storage alloy may be contained in the hydrogen storage complex mixed with the thermally conductive material.

Of course, the hydrogen storage complex may also be provided in the shape of a disk having a hollow. As the hydrogen storage complex contains a thermally conductive material, thermal conductivity can be improved, and thus hydrogen can be efficiently occluded and released.

The thermally conductive material is not particularly limited as long as it has a low weight and high thermal or electrical conductivity, but may be any one or more selected from a thermally conductive metal and a thermally conductive carbon body. The metal may be aluminum, gold, silver, tungsten, iron, platinum, or the like, and the carbon body may be graphite, carbon nanotubes, or the like.

As another example, the hydrogen storage complex of the present invention may further contain a resin. As the hydrogen storage complex further contains a resin, it can stably maintain its shape, thereby preventing it from collapsing due to the expansion of the hydrogen storage alloy that occurs when hydrogen is occluded and released.

The resin may be any one or more selected from phenol resin, epoxy resin, silicon resin, polyethylene, polypropylene, polyimide, and fluororesin. The resin serves to maintain the shape of the hydrogen storage complex, and may be formed by mixing with the hydrogen storage alloy or by coating the surface of the hydrogen storage alloy.

The hydrogen storage complex may contain 0.1 to 90 parts by weight of a thermally conductive material and 0.1 to 90 parts by weight of a resin based on 100 parts by weight of the hydrogen storage alloy. Specifically, it may contain 0.5 to 70 parts by weight of the thermal conductive material and 1 to 70 parts by weight of the resin based on 100 parts by weight of the hydrogen storage alloy. The hydrogen storage complex having such an amount has high thermal conductivity due to the thermally conductive material, and can be stably maintained in shape, so that it can be prevented from collapsing due to the expansion of the hydrogen storage alloy generated during occlusion and release of hydrogen.

The hydrogen storage complex is obtained by (D1) mixing a thermally conductive material and a resin to obtain a first mixture, (D2) mixing a hydrogen storage alloy with the first mixture to obtain a second mixture, (D3) the first 2 It can be prepared from the step of molding the mixture. After (D3), (D4) may be manufactured through a further curing step of curing the molded second mixture.

Specifically, in step (D1), 10 to 300 parts by weight of the resin, preferably 50 to 250 parts by weight, more preferably 70 to 150 parts by weight based on 100 parts by weight of the thermally conductive material to obtain a first mixture by mixing can At the above content, the first mixture has an appropriate viscosity and is easily mixed with a hydrogen storage alloy to be described later.

In step (D2), 0.1 to 90 parts by weight of the first mixture based on 100 parts by weight of the hydrogen storage alloy, specifically, 0.5 to 70 parts by weight of the first mixture with respect to 100 parts by weight of the hydrogen storage alloy to obtain a second mixture. can The hydrogen storage composite prepared through such an amount may have high thermal conductivity due to the thermally conductive material, and may have shape maintenance ability by the resin.

In step (D3), the second mixture is molded. The second mixture may be molded into a disk shape having a hollow therein through injection molding or compression molding, but is not limited thereto. In addition, the second mixture can be molded into various shapes through other conventionally known molding methods.

In step (D4), the final hydrogen storage complex can be obtained by curing the molded second mixture. Curing in step (D4) may be carried out at 0 to 500 °C, preferably at 100 to 300 °C, more preferably at 150 to 250 °C. The curing time is not limited as long as the hydrogen storage composite can be completely cured, but it can be cured more rapidly at a temperature in the above range.

The hydrogen storage complex manufactured through these steps has high thermal conductivity by the thermally conductive material and can stably maintain its shape, so that it can be prevented from collapsing due to the expansion of the hydrogen storage alloy that occurs during occlusion and release of hydrogen. have.

The present invention is an operating method of the above-described hydrogen storage system, including (A) supplying a refrigerant to the main storage unit and occluding the hydrogen supplied to the main storage unit in the hydrogen storage alloy. When hydrogen is supplied to the main storage unit in step (A), hydrogen is simultaneously supplied to and stored in the sub storage unit. The operation method of the hydrogen storage system of the present invention comprising the step (A) is to cool the hydrogen storage alloy with a refrigerant regardless of the ambient temperature so that hydrogen can be occluded in the hydrogen storage alloy, so that the main storage unit and the sub storage unit can be quickly charged with hydrogen.

Specifically, step (A) is a step of supplying a refrigerant to the main storage unit to occlude the hydrogen supplied to the main storage unit in a hydrogen storage alloy. In step (A), hydrogen is introduced from the hydrogen supply device at a pressure of 10 bar or less. can be Hydrogen produced by methods such as water electrolysis is produced at a low pressure of 10 bar or less, and by directly introducing hydrogen in a low pressure state without a separate compression process, the cost of using a mechanical compressor can be significantly reduced. . Step (A) may be made by the refrigerant circulation part of the hydrogen storage system. The refrigerant circulation unit may supply the refrigerant or the heat medium to the main storage unit. In step (A), the refrigerant circulation unit may supply the refrigerant to the main storage unit. When hydrogen is filled in the main storage unit in step (A), hydrogen may be supplied to and stored in the sub storage unit through the main valve. In step (A), the sub-storage unit may store hydrogen so that the fuel cell can be started. In step (A), the sub storage unit continuously starts the fuel cell until the temperature of the fruit, which will be described later, is heated to a temperature of 40 to 90°C, preferably 60 to 80°C, due to waste heat generated as the fuel cell is operated. and a sufficient amount of hydrogen to be driven can be stored.

In step (A), the control unit may perform a hydrogen storage mode. The control unit moves the refrigerant from the refrigerant tank to the heat exchange unit by operating a pump installed in the refrigerant circulation unit to supply the refrigerant to the main storage unit, and the refrigerant passing through the heat exchange unit may move into the main tank of the main storage unit. In this case, the heat exchange unit may be in a state in which waste heat does not exist, and heat exchange may not occur. Accordingly, the refrigerant is not converted into a heat medium, and the refrigerant moves to the main storage unit as it is, and the main storage unit can be cooled. In step (A), the refrigerant tank is connected to the main storage unit by the supply coupler and the receiving coupler, and the hydrogen supply device is also connected to the main storage unit by the coupler. The valve is closed so that the refrigerant supplied from the refrigerant tank to the main storage unit through the supply coupler is not received back into the refrigerant tank through the supply coupler.

The operation method of the hydrogen storage system of the present invention includes the steps of (B1) operating the fuel cell by supplying hydrogen from the sub-storage unit to the fuel cell, (B2) waste heat generated by the operation of the fuel cell is the refrigerant after step (A). and heat-exchanged to generate heat, (B3) supplying heat to the main storage unit and supplying hydrogen released as the main storage unit is heated to the sub-storage unit, and (B1) to (B3) are unit processes to supply hydrogen to the fuel cell repeatedly one or more times.

The operation method of the hydrogen storage system of the present invention as described above circulates the refrigerant supplied without additional refrigerant and uses waste heat generated during operation of the fuel cell as a heat source without a separate heating device. City energy efficiency is excellent. Since heat having a constant temperature can be supplied to the main storage unit regardless of the ambient temperature, hydrogen having a constant pressure can be provided, so that hydrogen can be more stably supplied to the fuel cell side.

Specifically, step (B1) is a step of supplying hydrogen from the sub storage unit to the fuel cell to operate the fuel cell. In step (B1), the sub storage unit supplies hydrogen to the fuel cell to start the fuel cell and then operate it. can Step (B1) may be performed depending on whether the fuel cell is operating.

Step (B2) is a step in which waste heat generated according to the operation of the fuel cell is heat-exchanged with a refrigerant to generate a fruit. In step (B2), the temperature of the waste heat is 30 to 200°C, preferably 50 to 150°C, more preferably may be 60 to 90 °C. Step (B2) may be performed by the refrigerant circulation unit of the hydrogen storage system and the refrigerant circulation unit of the fuel cell. In the heat exchange unit of the cooling medium circulation unit, the refrigerant supplied from the cooling medium circulation unit is heat-exchanged through the heat medium supplied through the refrigerant circulation unit and may be converted into heat medium. The heat source of the heat source of the refrigerant circulation part is the heat (waste heat) generated by the operation of the fuel cell. That is, in the heat exchange unit of the cooling medium circulating unit, the refrigerant supplied from the cooling medium circulating unit may be converted into heat from waste heat of the fuel cell as a heat source.

Step (B3) is a step of supplying the heat medium to the main storage unit and supplying hydrogen released as the main storage unit is heated to the sub storage unit. In step (B3), the heat medium is moved to the main tank of the main storage unit and heating the sub tank. to heat the hydrogen storage alloy. Accordingly, the hydrogen storage alloy releases hydrogen, and the released hydrogen is supplied to the sub storage unit. The supplied hydrogen can be used as fuel for the fuel cell.

After step (B3), as step (B1) is performed again, the fuel cell may maintain operation.

In steps (B1) to (B3), the control unit may perform a hydrogen use mode. The control unit may supply hydrogen from the sub-storage unit to the fuel cell by opening the sub-valve installed between the sub-storage unit and the fuel cell in step (B1). In the hydrogen use mode, the control unit may control the refrigerant already supplied to circulate between the main storage unit and the heat exchange unit. At this time, the main storage unit may be disconnected from the refrigerant tank by the supply coupler and the accommodating coupler connected to the refrigerant tank, and may also be disconnected from the hydrogen supply device. And the valve can be opened by the control unit. The supplied refrigerant passes through the heat exchange unit, and may be exchanged with waste heat generated according to the operation of the fuel cell to be converted into a heat medium. The converted fruit passes through the main storage unit, and the hydrogen stored in the hydrogen storage alloy can be released by heating the main storage unit. The fruit passes through the main reservoir and can be converted into a refrigerant. The converted refrigerant is again converted to heat through the heat exchange unit, is supplied to the main storage unit, and can be circulated by repeating this process.

The operation method of the hydrogen storage system of the present invention includes the steps of (C1) stopping the supply of hydrogen from the sub-storage unit to the fuel cell when the operation of the fuel cell is terminated, (C2) the residual heat in the fuel cell is heat exchanged with the refrigerant to generate heat The generating step, (C3) supplying fruit to the main storage unit and storing the hydrogen released as the main storage unit is heated in the sub storage unit; may be performed.

In the operating method of the present invention for performing the above steps, as hydrogen is stored in the sub-storage unit, necessary hydrogen can be stably supplied when the fuel cell is restarted later.

More specifically, step (C1) is a step of stopping the supply of hydrogen from the sub storage unit to the fuel cell. As the sub-valve is closed by the control unit, the supply of hydrogen to the fuel cell may be stopped.

Step (C2) is a step in which residual heat in the fuel cell is heat-exchanged with the refrigerant to generate heat. In step (C2), the refrigerant circulation unit of the fuel cell and the refrigerant circulation unit of the hydrogen storage system may be performed. After the operation of the fuel cell is terminated, residual heat may be present as waste heat generated during operation is still remaining. Accordingly, the refrigerant circulation unit of the fuel cell may supply heat to the heat exchange unit even after the operation of the fuel cell is terminated. For this reason, the refrigerant circulation unit can supply the circulating refrigerant to the main storage unit side after converting the refrigerant.

Step (C3) is a step of supplying fruit to the main storage unit and storing the hydrogen released as the main storage unit is heated in the sub storage unit. Since the sub-valve is closed in step (C1), the hydrogen released from the main storage unit is It may be stored in the sub-storage unit. Accordingly, in step (C3), the sub-storage unit may store a greater amount of hydrogen than hydrogen discharged from the hydrogen storage alloy during operation of the fuel cell. The sub storage unit continuously starts and drives the fuel cell until the temperature of the fruit, which will be described later, is heated to a temperature of 40 to 90 ° C, preferably 60 to 80 ° C, due to waste heat generated as the fuel cell to be described later is operated. A sufficient amount of hydrogen can be stored.

In (C1) to (C3), the control unit may perform the sub-hydrogen storage mode. The control unit may block the sub-valve, and circulate the refrigerant and the heat medium so that the heat medium can be supplied to the main storage unit as in (B2). Accordingly, hydrogen is continuously supplied to the sub-storage unit so that a sufficient amount of hydrogen can be stored in the sub-storage unit. In this case, the heat exchange unit may retain residual heat (residual waste heat) even when the operation of the fuel cell is stopped, so that heat exchange may be possible.

The hydrogen storage system and its operating method according to the present invention described above can store a sufficient amount of hydrogen in the sub-storage unit separately from the main storage unit in which the hydrogen storage alloy is embedded, thereby providing sufficient hydrogen required for starting the fuel cell. can In addition, the charging and discharging rates of hydrogen can be quickly performed by the cooling medium circulation unit, and hydrogen at a constant pressure can be provided to the fuel cell, so that the operation of the fuel cell with high stability can be performed.

In particular, the hydrogen storage system and the operating method thereof of the present invention are preferably applied to a fuel cell vehicle. The hydrogen storage system and operating method of the present invention are relatively light and compact, and thus are suitable for fuel cell vehicles. In addition, the hydrogen storage system and operating method of the present invention are very suitable for a fuel cell vehicle that needs to be frequently charged according to usage because the charging and discharging speed is fast.

Hereinafter, the present invention will be described in detail by way of Examples, but these are for describing the present invention in more detail, and the scope of the present invention is not limited by the Examples below.

_{A hydrogen storage complex was prepared using TiMn 2} as a hydrogen storage alloy and aluminum as a thermally conductive material. _{After mixing TiMn 2} with aluminum, it was prepared by compression molding. The prepared hydrogen storage complex contained TiMn ₂ 85w% and aluminum 15w%. A sub-tank and a main storage unit were constructed using the prepared hydrogen storage complex, and a hydrogen storage system was constructed. Thereafter, by cooling the main storage unit through the refrigerant, hydrogen was occluded in the hydrogen storage complex. Hydrogen was supplied to the sub-tank at a pressure of 40 bar through a hydrogen supply device, and the temperature of cold water, which is a refrigerant for cooling, was controlled to 15 to 18°C.

_{A hydrogen storage complex was prepared using TiMn 2} as a hydrogen storage alloy, aluminum as a thermally conductive material, and Resin A. _{After mixing TiMn 2} with aluminum and compression molding, the resin A was coated on the compression molded body to prepare a hydrogen storage composite. The prepared hydrogen storage complex contained TiMn ₂ 80w%, aluminum 10w%, and Resin A 10w%. A sub-tank and a main storage unit were constructed using the prepared hydrogen storage complex, and a hydrogen storage system was constructed. Thereafter, by cooling the main storage unit through the refrigerant, hydrogen was occluded in the hydrogen storage complex. Hydrogen was supplied to the sub-tank at a pressure of 40 bar through a hydrogen supply device, and the temperature of cold water, which is a refrigerant for cooling, was controlled to 15 to 18°C.

When preparing the hydrogen storage composite of Example 2, the hydrogen storage composite was prepared in the same manner as in Example 2, except that the _{resin A was not coated after compression molding, and the resin A was mixed with aluminum and TiMn 2 before compression molding.} did. The prepared hydrogen storage complex contained _{40w% of TiMn 2} , 10w% of aluminum, and 50w% of Resin A. A sub-tank and a main storage unit were constructed using the prepared hydrogen storage complex, and a hydrogen storage system was constructed. Thereafter, by cooling the main storage unit through the refrigerant, hydrogen was occluded in the hydrogen storage complex. Hydrogen was supplied to the sub-tank at a pressure of 40 bar through a hydrogen supply device, and the temperature of cold water, which is a refrigerant for cooling, was controlled to 15 to 18°C.

A hydrogen storage complex was prepared in the same manner as in Example 3, except that, when preparing the hydrogen storage complex of Example 3, resin B was used instead of resin A. The prepared hydrogen storage complex contained _{40w% of TiMn 2} , 10w% of aluminum, and 50w% of resin B. A sub-tank and a main storage unit were constructed using the prepared hydrogen storage complex, and a hydrogen storage system was constructed. Thereafter, by cooling the main storage unit through the refrigerant, hydrogen was occluded in the hydrogen storage complex. Hydrogen was supplied to the sub-tank at a pressure of 40 bar through a hydrogen supply device, and the temperature of cold water, which is a refrigerant for cooling, was controlled to 15 to 18°C.

A hydrogen storage complex was prepared in the same manner as in Example 3, except that the prepared hydrogen storage complex contained 80w% _{of TiMn 2, 10w% of aluminum, and 10w% of Resin A.} A sub-tank and a main storage unit were constructed using the prepared hydrogen storage complex, and a hydrogen storage system was constructed. Thereafter, by cooling the main storage unit through the refrigerant, hydrogen was occluded in the hydrogen storage complex. Hydrogen was supplied to the sub-tank at a pressure of 40 bar through a hydrogen supply device, and the temperature of cold water, which is a refrigerant for cooling, was controlled to 15 to 18°C.

A hydrogen storage complex was prepared in the same manner as in Example 5, except that in the preparation of Example 5, Resin B was used instead of Resin A. The prepared hydrogen storage complex contained TiMn ₂ 80w%, aluminum 10w%, and resin B 10w%. A sub-tank and a main storage unit were constructed using the prepared hydrogen storage complex, and a hydrogen storage system was constructed. Thereafter, by cooling the main storage unit through the refrigerant, hydrogen was occluded in the hydrogen storage complex. Hydrogen was supplied to the sub-tank at a pressure of 40 bar through a hydrogen supply device, and the temperature of cold water, which is a refrigerant for cooling, was controlled to 15 to 18°C.

9 is a view showing the pressure-composition isotherm of the hydrogen storage complex according to Example 6 of the present invention, and FIG. 10 is a graph showing the amount of hydrogen storage per hour of the hydrogen storage complex according to Example 6 of the present invention. Referring to FIGS. 9 to 10 , it can be seen that hydrogen of 40 bar at 15° C. is stored in the hydrogen storage complex, and it takes 3 minutes or less for the hydrogen storage complex to reach about 90% of the maximum hydrogen storage.

11 is a photograph showing the hydrogen storage complex according to Examples 1 to 6 of the present invention. 11(a) shows a photograph before hydrogen occlusion in Example 1, and (b) shows after hydrogen occlusion in Example 1. FIG. (c) shows after hydrogen occlusion in Example 2, and (d) shows after hydrogen occlusion in Example 3. In addition, (e) shows after hydrogen occlusion in Example 4, (f) shows after hydrogen occlusion in Example 5, and (g) shows after hydrogen occlusion in Example 6.

Referring to FIG. 11 , in the case of Example 1 in which no resin was mixed, it was found that collapse occurred due to expansion after occlusion of hydrogen. On the contrary, in the case of Examples 2 to 6 in which the resin of the present invention was mixed, it was found that almost no collapse occurred compared to Example 1, and in particular, in the case of Examples 4 and 6 in which Resin B was mixed, the collapse was I could confirm that it didn't happen at all. Moreover, in the case of Resin B, no disintegration occurred even when a small amount was mixed.

10: main storage unit 11: main storage unit
12: inner space 13: sub tank
14: main hydrogen flow path 15: hydrogen storage alloy
21: hydrogen supply device 30: sub storage unit
35: main valve 37: sub-valve
40: shape maintaining part 41: spiral tube
42: side hydrogen transfer path 47: mesh tube
50: refrigerant circulation unit 51: refrigerant tank
53: pump 55: heat exchange unit
57: valve 58: branch line
60: support member 70: fuel cell
71: body 75: refrigerant circulation part
77: circulation line 78: air cooling fan
79: pump

Claims (22)

a main storage unit in which hydrogen is supplied and a hydrogen storage alloy is built in;
a sub storage unit communicating with the main storage unit to store hydrogen discharged from the main storage unit; and
a cooling medium circulation unit capable of storing hydrogen in the main storage unit or the sub storage unit by heating or cooling the main storage unit through a heat medium or a refrigerant; and comprising;
Including; a fuel cell for generating power by receiving hydrogen from the sub-storage unit;
The refrigerant circulation unit stores the refrigerant and includes a refrigerant tank connected to the main storage unit;
a heat exchange unit for supplying a branched coolant from the coolant tank and exchanging the branched coolant; and
Including; a control unit for controlling the supply of the refrigerant and the heat medium to the main storage unit;
The refrigerant circulation unit uses waste heat generated in the fuel cell, a hydrogen storage system. delete The method of claim 1,
the control unit
In the hydrogen storage mode, the refrigerant is supplied from the refrigerant tank to the main storage unit,
A hydrogen storage system for supplying heat from the heat exchange unit to the main storage unit in the hydrogen use mode. delete delete The method of claim 1,
A hydrogen storage system further comprising a main valve for preventing a reverse flow of hydrogen between the main storage unit and the sub storage unit. The method of claim 1,
The main storage unit
A main tank for accommodating a refrigerant or fruit therein, and
It is built in the inside of the main tank and includes a sub-tank in which a hydrogen storage alloy is embedded,
The hydrogen storage alloy is a hydrogen storage system that forms a main hydrogen flow path through which hydrogen can flow in the sub-tank. 8. The method of claim 7,
The main storage unit
The hydrogen storage system further comprising a shape maintaining part which is inserted and installed to allow movement of hydrogen into the main hydrogen flow path so as to maintain the shape of the main hydrogen flow path. 9. The method of claim 8,
The shape maintaining part extends along the extension direction of the main hydrogen flow path, both ends are opened to form a sub-hydrogen flow path communicating with the main hydrogen flow path therein, and at least one side of the side where hydrogen can be moved from the hydrogen storage alloy A hydrogen storage system with a hydrogen flow path. ◈Claim 10 was abandoned when paying the registration fee.◈ 10. The method of claim 9,
The shape maintaining part is a hydrogen storage system having a spiral tube extending in a spiral direction along the inner surface of the main hydrogen passage. ◈Claim 11 was abandoned when paying the registration fee.◈ 10. The method of claim 9,
The shape maintaining part is a hydrogen storage system having a mesh tube manufactured by braiding or woven. ◈Claim 12 was abandoned when paying the registration fee.◈ 10. The method of claim 9,
The main storage unit
The hydrogen storage system further comprising a support member that supports the shape maintaining part and is installed in the sub-hydrogen flow path of the shape maintaining part to enable the flow of hydrogen. ◈Claim 13 was abandoned when paying the registration fee.◈ 13. The method of claim 12,
The support member extends from the inside of the sub-hydrogen channel in the direction of the sub-hydrogen channel, forms an inner space with both ends open, and a hydrogen storage system having at least one perforated tube communicating with the inner space. . ◈Claim 14 was abandoned at the time of payment of the registration fee.◈ The method of operating the hydrogen storage system of any one of claims 1, 3 and 6 to 13,
(A) supplying a refrigerant to the main storage unit and occluding the hydrogen supplied to the main storage unit in the hydrogen storage alloy;
When hydrogen is supplied to the main storage unit, hydrogen is simultaneously supplied to and stored in the sub storage unit. ◈Claim 15 was abandoned when paying the registration fee.◈ 15. The method of claim 14,
After step (A),
(B1) supplying hydrogen from the sub storage unit to the fuel cell to operate the fuel cell;
(B2) generating heat by heat-exchanging waste heat generated by the operation of the fuel cell with the refrigerant;
(B3) supplying the fruit to the main storage unit and supplying hydrogen released as the main storage unit is heated to the sub storage unit;
A method of operating a hydrogen storage system for supplying hydrogen to the fuel cell by repeating (B1) to (B3) as a unit process one or more times. ◈Claim 16 was abandoned at the time of payment of the registration fee.◈ 16. The method of claim 15,
When the operation of the fuel cell is terminated,
(C1) stopping the supply of hydrogen from the sub storage unit to the fuel cell;
(C2) generating heat by exchanging residual heat with the refrigerant in the fuel cell;
(C3) supplying the fruit to the main storage unit and storing the hydrogen released as the main storage unit is heated in the sub storage unit; a method for operating a hydrogen storage system that is performed. The method of claim 1,
The hydrogen storage alloy is mixed with a thermally conductive material and contained in the hydrogen storage complex. 18. The method of claim 17,
The hydrogen storage complex is a hydrogen storage system further containing a resin. 19. The method of claim 18,
The hydrogen storage complex is a hydrogen storage system containing 0.5 to 70 parts by weight of a thermal conductive material and 1 to 70 parts by weight of a resin based on 100 parts by weight of the hydrogen storage alloy. ◈Claim 20 was abandoned at the time of payment of the registration fee.◈ The hydrogen storage complex according to claim 18,
(D1) mixing a thermally conductive material and a resin to obtain a first mixture;
(D2) mixing a hydrogen storage alloy with the first mixture to obtain a second mixture; and
(D3) forming the second mixture; hydrogen storage system to be prepared from. ◈Claim 21 has been abandoned at the time of payment of the registration fee.◈ 21. The method of claim 20,
After the hydrogen storage complex (D3),
(D4) a curing step of curing the molded second mixture; hydrogen storage system to be prepared from.
4. The method of claim 3,
The refrigerant tank is connected to the main storage unit by a connecting member,
In the hydrogen storage mode,
The refrigerant tank is connected to the main storage unit to supply the refrigerant to the main storage unit,
In the hydrogen use mode,
A hydrogen storage system in which the refrigerant tank is disconnected from the main storage unit and separated.

Images