US20110132574A1

US20110132574A1 - Hydrogen storage system using hydrogen storage material

Info

Publication number: US20110132574A1
Application number: US12/859,360
Authority: US
Inventors: Hoonhui Lee; Hyungki Kim; Youngmin Choi
Original assignee: Hyundai Motor Co; Kia Motors Corp
Current assignee: Hyundai Motor Co; Kia Corp
Priority date: 2009-12-03
Filing date: 2010-08-19
Publication date: 2011-06-09
Also published as: KR20110062363A

Abstract

The present invention relates to a hydrogen storage system using a hydrogen storage material and can increase a heat exchanging efficiency by improving a contact frequency to the heat exchanger by vibrating the heat exchanger that is mounted in the hydrogen storage tank using the hydrogen storage material by using a vibrator to induce resonance vibration of the packed storage material powder.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims under 35 U.S.C. §119(a) priority to Korean Patent Application Number 10-2009-0119066, filed Dec. 3, 2009, the entire contents of which application is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates in general to a hydrogen storage system for a vehicle, and more particularly to a hydrogen storage system using a hydrogen storage material that can largely lower a charging time when a material that reversibly stores/discharges hydrogen is used.
2. Description of Related Art
In general, fuel cell vehicles require hydrogen in an amount of 5 kg or more in order to travel a distance in one charge.
However, high pressure (35 or 70 MPa) hydrogen storage systems that are currently used have limits in their packaging for installation in vehicles due to insufficient volume storage density.
Accordingly, a technology using a hydrogen storage material that has a high storage density, that is, a hydrogen storage alloy, a chemical hydrogen material or a porous material has been developed.
In particular, the hydrogen storage alloy or complex metal hydrides address the long charging time that is due to excessive physical or chemical reaction heat that is generated when hydrogen is charged (stored), but since the hydrogen storage alloy can reversibly store and discharge hydrogen and has a high volume storage density in respect to high pressure hydrogen, its application to hydrogen storage systems has been investigated.
The hydrogen storage system as described above has been developed such that a heat exchanger is inserted into the hydrogen storage system so that heat is exchanged due to the reaction heat of the hydrogen storage alloy.
However, if the size of the heat exchanger is made larger by increasing a contact area between the storage material and the heat exchanger in order to improve heat exchanging performance, a hydrogen charging time may be lowered, but the charging space of the hydrogen storage material is made narrow.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known in this country to a person skilled in the art.

BRIEF SUMMARY OF THE INVENTION

Preferred aspects of the present invention provide a hydrogen storage system using a hydrogen storage material, which suitably lowers a hydrogen charging time while the size of the heat exchanger is not suitably increased by improving heat exchanging performance and by improving a contact frequency between the heat exchanger and the storage material, and suitably prevents the charging space of the hydrogen storage material from being made small.
Preferred embodiments of the present invention provide a hydrogen storage system using a hydrogen storage material, that preferably comprises a heat exchanger that cycles a heat transfer medium in a hydrogen storage tank made with a hydrogen storage alloy, wherein the heat exchanger preferably includes a vibration unit that applies vibration to the heat transfer medium so that a flow is converted into a vortex.
In preferred embodiments, the vibrator is a piezoelectric vibrator.
In further preferred embodiments, the vibration unit is mounted in the heat exchanging tube or in a heat transfer medium chamber that allows a heat transfer medium to flow thereinto.
In other further preferred embodiments, the vibration unit vibrates the heat exchanger by using a resonance frequency of the hydrogen storage material.
Preferably, the vibration unit generates a vibration frequency by using a resonance frequency of the hydrogen storage material regularly or in a predetermined cycle.
According to still further preferred embodiments, the heat exchanger further increases a heat exchanging volume by suitably forming a heat exchanging pin so that the heat exchanging volume of the heat exchanging tube that makes a flow path of the heat transfer medium is suitably increased and forming a groove that is suitably obtained by modifying the heat exchanging tube between the pins.
According to further preferred embodiments of the present invention, since heat exchanging performance is suitably improved, the hydrogen charging time of the hydrogen storage system using the hydrogen storage material may be suitably lowered while the size of the heat exchanger is not increased, such that the packing space of the hydrogen storage material is not lost.
Further, according to preferred embodiments, since the present invention is independently constituted in a known heat exchanger, a charging performance of the hydrogen storage system may be suitably increased while a know heat exchanger is not largely modified.
It is understood that the term “vehicle” or “vehicular” or other similar term as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g. fuels derived from resources other than petroleum).
As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example both gasoline-powered and electric-powered.
The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description of the Invention, which together serve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated by the accompanying drawings which are given hereinafter by way of illustration only, and thus are not limitative of the present invention, and wherein:

FIG. 1 is an exemplary configuration view of a hydrogen storage system using a hydrogen storage material, which is provided with an internal heat exchanger according to the present invention.

FIGS. 2A and 2B are exemplary configuration views of a heat exchanging tube from which a heat exchanging pin of the internal heat exchanger is removed according to the present invention.

FIG. 3 is a cross-sectional view of a heat exchanging tube in which a heat exchanging pin of the internal heat exchanger according to the present invention is formed.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.

DETAILED DESCRIPTION OF THE INVENTION

As described herein, the present invention includes a hydrogen storage system comprising a heat exchanger, a hydrogen storage tank comprised of a hydrogen storage alloy, and a heat transfer medium, wherein the heat exchanger includes a vibration unit.
In preferred embodiments, the heat transfer medium is cycled by the heat exchanger in the hydrogen storage tank.
In other preferred embodiments, the vibration unit applies vibration to the heat transfer medium so that a flow is converted into a vortex.
Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
According to certain preferred embodiments, and as shown in FIG. 1, for example, FIG. 1 illustrates a configuration view of a hydrogen storage system using a hydrogen storage material that is provided with an internal heat exchanger. According to certain preferred embodiments, the present invention preferably includes a vibration unit that largely lowers a hydrogen charging time by suitably improving heat exchanging performance while the size of an internal heat exchanger 2 of a hydrogen storage tank 1 using a hydrogen storage alloy is not suitably increased.
According to further preferred embodiments, a heat exchanger 2 implements a function that absorbs the internal heat of a hydrogen storage tank 1 by using a heat exchanging medium and a function that receives heat from the heat transfer medium and suitably transfers heat to the hydrogen storage material and a heat exchanging pin 5.
Preferably, a heat exchanger 2 according to the certain preferred embodiments can satisfy both sides between the heat exchanger and the hydrogen charging space.
Accordingly, in preferred exemplary embodiments, the heat exchanger 2 is suitably configured by a heat exchanging tube 3 that is suitably inserted into a hydrogen storage tank 1 and performs heat exchange through the cycling heat transfer medium by the reaction heat of the hydrogen storage alloy, heat exchanging pin 5 that is suitably mounted so as to increase the heat exchanging area of heat exchanging tube 3, a chamber 4 that suitably receives the medium after it flows into heat exchanging tube 3 and cycles, and a vibration unit that vibrates the heat transfer medium before it flows into heat exchanging tube 3.
According to further preferred embodiments and as shown in FIG. 2A for example, FIG. 2A illustrates a heat exchanging tube 3 according to preferred embodiments of the present embodiment.
As shown in the drawing, a heat exchanging tube 3 is suitably configured by an integral tube that has an inlet 3 a that inflows the heat transfer medium and an outlet 3 b that outflows it cycling therein and suitably discharges it again at ends thereof, but the tube has a structure that has a plurality of repetition paths that repeatedly cross the internal space of a hydrogen storage tank 1 and cycles the heat transfer medium.
Preferably, a heat exchanging tube 3 is a path that inflows the heat transfer medium, and allows the flowing heat transfer medium to be suitably contacted with the hydrogen storage material and heat exchanging pin 5, thereby absorbing the heat.
In other embodiments of the present invention, a heat exchanging tube 3 absorbs the internal heat of hydrogen storage tank 1 by the heat transfer medium and receives heat that is suitably provided from the heat transfer medium and suitably transfers heat to the hydrogen storage material and heat exchanging pin 5, which is suitably performed by heating.
According to further preferred embodiments, a heat exchanging tube 3 has various cross-sectional shapes so as to suitably increase the heat exchanging efficiency through heat exchanging pin 5.
As an example of the cross section of a heat exchanging tube 3, as shown in FIG. 3, for example, it can be suitably bent and its cross section can be suitably changed by forming the groove along the length direction of heat exchanging tube 3.
Chamber 4 according to further preferred embodiments of the present invention, wraps inlet 3 a and outlet 3 b of heat exchanging tube 3 and fixes it, and has a structure in which the heat transfer medium is suitably discharged from the inside thereof to inlet 3 a and flows through outlet 3 b thereinto.
Preferably, to provide the structure of a chamber 4, a valve and the like is provided, which is suitably the same as the structure that is applied to implement the same function.
According to further preferred embodiments, a heat exchanging pin 5 functions to suitably increase a tube volume by suitably forming it on each tube that is configured by a heat exchanging tube 3, and preferably heat exchanging is suitably performed when cooling and heating are conducted by contacting the storage material and heat exchanging tube 3 in the internal space of hydrogen storage tank 1.
The vibration unit according to preferred embodiments of the present invention implements a function that suitably improves heat exchange performance between a heat exchanging tube 3 and a heat transfer medium by vibrating a heat exchanger 2 while it is attached to the heat exchanger 2, and heat exchanging performance between the heat exchanging pin and the storage material powder.
Preferably, the vibration unit vibrates the hydrogen storage material that is contacted with the heat exchanger by vibrating the heat exchanger and increases an effective contact area to the heat exchanger, thereby suitably improving the heat transfer efficiency.
Further, the flow of heat transfer medium is suitably converted into the vortex to double an improvement of heat transfer efficiency.
Accordingly, in further preferred embodiments, the vibration unit is suitably configured by a vibrator 10 that applies vibration to a heat exchanger 2, and the vibrator 10 preferably connects a wire 11 to suitably provide power, and the power is preferably controlled by using a separate controller.
According to other further preferred embodiments of the present invention, the controller suitably implements controlling that is performed so that the vibration number of the vibrator 10 suitably corresponds to the resonance frequency of the storage material powder to further increase the heat exchanging performance.
Preferably, the vibrator 10 is mounted in various positions so as to increase the vibration performance of the heat transfer medium, and a piezoelectric vibrator is suitably applied.
According to certain exemplary embodiments, a vibrator 10 is suitably mounted at a chamber 4 that receives the heat transfer medium, thereby vibrating a heat exchanger 2 and suitably forming the vortex in the flow of heat transfer medium as shown in FIG. 2A.
Alternatively, in other further embodiments of the present invention, a vibrator 10, as shown in FIG. 2B, is suitably mounted at a heat exchanging tube 3, thereby vibrating heat exchanger 2.
As described herein, in preferred embodiments of the present invention, a heat exchanging efficiency is improved in the course of cycling the heat transfer medium by an increase in heat exchange area through the groove shapes of heat exchanging pin 5 and heat exchanging tube 3 in a hydrogen storage tank 1, and the heat exchanging efficiency is further improved by using a change of heat transfer medium flow that cycles to heat a exchanging tube 3 by vibrating the heat transfer medium in a predetermined frequency by using a vibrator 10.
According to preferred embodiments of the present invention, it is possible to further increase the heat exchanging efficiency by setting the vibration number that is suitably applied to the heat transfer medium in a vibrator 10 to the resonance frequency of the storage material powder to suitably increase the effective contact area between the storage material and heat exchanger 2.
Further, in preferred embodiments, when vibration is suitably applied through a vibrator 10 to the heat transfer medium, if the vibration is applied in a predetermined cycle while the vibration is not constant, a higher heat exchanging performance may be generated.
As described herein, in preferred embodiments of the present invention, since the heat exchanging performance efficiency is largely increased by only a simple function that applies the vibration to the heat transfer medium so that the flow thereof is suitably converted into the vortex, the size of heat exchanger 2 is not suitably increased, such that the hydrogen packing space in a hydrogen storage tank 1 is not lost.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.

Claims

1. A hydrogen storage system using a hydrogen storage material, comprising:

a heat exchanger that cycles a heat transfer medium in a hydrogen storage tank made with a hydrogen storage alloy,

wherein the heat exchanger includes a vibration unit that applies vibration to the heat transfer medium so that a flow is converted into a vortex.

2. The hydrogen storage system using a hydrogen storage material as defined in claim 1, wherein the vibration unit is a piezoelectric vibrator.

3. The hydrogen storage system using a hydrogen storage material as defined in claim 1, wherein the vibration unit is mounted in the heat exchanging tube.

4. The hydrogen storage system using a hydrogen storage material as defined in claim 1, wherein the vibration unit is mounted in a heat transfer medium chamber that allows a heat transfer medium to flow thereinto.

5. The hydrogen storage system using a hydrogen storage material as defined in claim 1, wherein the vibration unit vibrates the heat exchanger by using a resonance frequency of the hydrogen storage material.

6. The hydrogen storage system using a hydrogen storage material as defined in claim 5, wherein the vibration unit generates a vibration frequency by using a resonance frequency of the hydrogen storage material regularly or in a predetermined cycle.

7. The hydrogen storage system using a hydrogen storage material as defined in claim 1, wherein the heat exchanger further increases a heat exchanging volume by forming a heat exchanging pin so that the heat exchanging volume of the heat exchanging tube that makes a flow path of the heat exchanging medium is increased and forming a groove that is obtained by modifying the heat exchanging tube between the pins.

8. A hydrogen storage system comprising:

a heat exchanger;

a hydrogen storage tank comprised of a hydrogen storage alloy; and

a heat transfer medium,

wherein the heat exchanger includes a vibration unit.

9. The hydrogen storage system of claim 8, wherein the heat transfer medium is cycled by the heat exchanger in the hydrogen storage tank.

10. The hydrogen storage system of claim 8, wherein the vibration unit applies vibration to the heat transfer medium so that a flow is converted into a vortex.