Note: Descriptions are shown in the official language in which they were submitted.
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HYDROGEN STORAGE CONTAINER
FIELD OF THE INVENTION
The present invention relates to hydrogen storage containers and,
particularly, to
containers for containing metallic particles capable of forming metal
hydrides.
BACKGROUND OF THE INVENTION
Metal hydrides, in the form of metallic particles, are used to store hydrogen
in many
different sizes and shaped containers. In order to facilitate the charging and
discharging of the
hydrogen, the metal hydride and, consequently, the container, needs to be
cooled or heated. To
facilitate good performance of the container (desorption rate, filling time,
etc.), the inside of the
container requires efficient heat exchange means to improve the
charging/discharging kinetics.
Repeated absorption and desorption cycles typically result in the
decrepitation of the
metal hydride particles. By virtue of the decrepitation, a localized increase
in packing fraction of
the metallic particles is observed. Such increase in packing fraction, coupled
with particle
expansion during absorption, potentially creates localized stresses on the
container. It is
desirable to have means inside the container to absorb part of this volumetric
expansion so that
stress on the container is mitigated or avoided.
SUMMARY OF THE INVENTION
The present invention provides a container configured for containing metallic
particles,
the metallic particles capable of absorbing hydrogen such that the metallic
particles expand upon
the absorption of hydrogen, the container including an inner surface,
comprising a liner disposed
within the container such that a void space is provided between the liner and
the inner surface,
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wherein the liner engages the inner surface to substantially prevent ingress
of metallic particles,
when the metallic particles are contained in the container, into the void
space.
In another broad aspect, the present invention provides a container configured
for
containing at least metallic particles, the metallic particles capable of
absorbing hydrogen such
that the metallic particles expand upon the absorption of hydrogen, the
container defining a
container space and including an inner surface, comprising a liner disposed
within the container
space and engaging the inner surface for defining (i) a storage space
configured to contain the
metallic particles and (ii) a void space configured to contract as the
metallic particles expand
upon the absorption of hydrogen, wherein, when the metallic particles are
contained in the
storage space, the engagement of the liner to the inner surface limits ingress
of the metallic
particles into the void space from the storage space.
In a further broad aspect, the present invention provides a container
configured for
containing at least metallic particles and gaseous hydrogen, the metallic
particles capable of
absorbing hydrogen such that the metallic particles expand upon the absorption
of hydrogen, the
container including an inner surface, comprising a liner disposed within the
container such that a
void space is provided between the liner and the inner surface, wherein the
liner engages the
inner surface to limit ingress of metallic particles, when the metallic
particles are contained in the
container, into the void space.
In a further broad aspect, the present invention provides a container
configured for
containing at least gaseous hydrogen and metallic particles, the metallic
particles capable of
absorbing hydrogen such that the metallic particles expand upon the absorption
of hydrogen, the
container defining a container space and including an Timer surface,
comprising a liner disposed
within the container space and engaging the inner surface for defining (i) a
storage space
configured to contain the metallic particles and (ii) a void space configured
to contract as the
metallic particles expand upon the absorption of hydrogen, wherein, when the
metallic particles
are contained in the storage space, the engagement of the liner to the inner
surface substantially
prevents ingress of the metallic particles into the void space from the
storage space.
In one aspect, the present invention provides the container wherein the liner
is
sufficiently flexible to deform in response to the expansion of the metallic
particles.
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In another aspect, the present invention provides the container wherein the
liner is shaped
to define (i) a storage space configured to contain metallic particles and
(ii) a void space
configured to contract as the metallic particles expand upon the absorption of
the hydrogen.
In yet another aspect, the present invention provides the container wherein
the liner bears
against the wall to substantially prevent or limit ingress of the metallic
particles into the void
space from the storage space when the storage space contains the metallic
particles.
In a further aspect, the present invention provides the container wherein the
liner abuts
the wall to substantially prevent or limit ingress of the metallic particles
into the void space from
the storage space when the storage space contains the metallic particles.
In yet a further aspect, the present invention provides the container wherein
the liner is
urged against the wall to substantially prevent or limit ingress of the
metallic particles into the
void space from the storage space when the storage space contains the metallic
particles.
In yet another aspect, the present invention provides the container wherein
the liner is
sufficiently resilient such that the liner has a tendency to reverse at least
a portion of the
deformation in response to discharging of hydrogen from the metallic
particles.
In a further aspect, the present invention provides the container wherein the
container
includes a sidewall and an axis, the sidewall defining at least a portion of
the inner surface and
being spaced apart from and extending 360° about the axis in a plane,
and wherein at least a
portion of the liner is disposed between the sidewall and the axis and extends
360° about the axis
in the plane.
In another aspect, the present invention provides the container wherein the at
least a
portion of the liner opposes the sidewall.
In yet another aspect, the present invention provides the container wherein at
least a
portion of the void space is disposed between the sidewall and the at least a
portion of the liner.
In a further aspect, the present invention provides the container wherein each
of the
sidewall and the liner is substantially tubular.
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In another aspect, the present invention provides the container wherein the
liner includes
corrugations defined by alternating ridges and grooves, each of the ridges and
grooves extending
transversely relative to the plane.
In yet a further aspect, the present invention provides the container wherein
at least one
of the ridges is configured to contact the sidewall when the metallic
particles axe contained in the
storage space.
In another aspect, the present invention provides the container further
comprising a
thermally conductive structure disposed in the storage space and in contact
with the liner and
configured for effecting heat transfer between the metallic particles and the
liner.
In another aspect, the present invention provides the container wherein the
liner is stiffer
than the container.
The present invention additionally provides a method of assembling a storage
system for
containing metallic particles capable of absorbing hydrogen to become charged
with hydrogen
comprising providing a container including an inlet and an inner surface
defining a container
space, inserting a magnetically responsive liner into the container space
through the inlet, and
applying a magnetic force sufficient to urge the liner against the inner
surface of the container.
In another aspect, the present invention provides the method wherein the
magnetic force
is generated externally of the container.
In another aspect, the present invention provides the method wherein the liner
being
inserted into the container space has a spiral configuration, and the
application of the magnetic
force effects expansion of the liner from the spiral configuration.
In another aspect, the present invention provides the method further
comprising the step
of inserting a plurality of tubes into the container space through the inlet
when the magnetic
force is acting on the liner.
In another broad aspect, the present invention provides a method of assembling
a
container for containing metallic particles capable of absorbing hydrogen to
become charged
with hydrogen comprising providing a container including an inlet and an inner
surface
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defining a container space, inserting a magnetically responsive liner into the
container space
through the inlet, applying a magnetic force sufficient to urge the liner
against the inner surface
of the container, when the magnetic force is acting on the liner, inserting a
plurality of tubes into
the container space through the inlet so as to urge the liner into engagement
with the inner
surface so as to define (i) a storage space configured to contain the metallic
particles and (ii) a
void space configured to contract as the metallic particles expand upon the
absorption of
hydrogen, and terminating the application of the magnetic force, and inserting
a plurality of
metallic particles into the storage space.
In this respect, in one aspect, the present invention provides the method
wherein the
magnetic force is generated externally of the container.
In another aspect, the present invention provides the method wherein the liner
being
inserted into the container space has a spiral configuration, and the
application of the magnetic
force effects expansion of the liner from the spiral configuration.
In yet another broad aspect, the present invention provides a method of
assembling a
container for containing metallic particles capable of absorbing hydrogen to
become charged
with hydrogen comprising providing a container including an inlet and an inner
surface defining
a container space, rolling a magnetically responsive liner about a mandrel so
that the liner
assumes a spiral configuration about the mandrel, when the liner is rolled
about the mandrel,
inserting the liner into the container space through the inlet, releasing the
liner from the mandrel,
removing the mandrel from the container space through the inlet, and applying
a magnetic force
sufficient to urge the liner against the inner surface of the container.
In another aspect, the present invention provides the method wherein the
magnetic force
is generated externally of the container.
In this respect, in one aspect, the present invention provides the method
wherein the liner
being inserted into the container space has a spiral configuration, and the
application of the
magnetic force effects expansion of the liner from the spiral configuration.
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In another aspect, the present invention provides the method fixrther
comprising the step
of inserting a plurality of tubes into the container space through the inlet
when the magnetic
force is acting on the liner.
The present invention also provides a method of assembling a container for
contaiiung
metallic particles capable of absorbing hydrogen to become charged with
hydrogen comprising
providing a container including an inlet and an inner surface defining a
container space, rolling a
magnetically responsive liner about a mandrel so that the liner assumes a
spiral configuration
about the mandrel, when the liner is rolled about the mandrel inserting the
liner into the container
space through the inlet, releasing the liner from the mandrel, removing the
mandrel from the
container space through the inlet, applying a magnetic force sufficient to
urge the liner against
the inner surface of the container, when the magnetic force is acting on the
liner, inserting a
plurality of tubes into the container space through the inlet so as to urge
the liner into
engagement with the inner surface so as to define (i) a storage space
configured to contain the
metallic particles and (ii) a void space configured to contract as the
metallic particles expand
upon the absorption of hydrogen, terminating the application of the magnetic
force, and inserting
a plurality of metallic particles into the storage space.
In another aspect, the present invention provides the method wherein the
magnetic force
is generated externally of the container.
In another aspect, the present invention provides the method wherein the liner
being
inserted into the container space has a spiral configuration, and the
application of the magnetic
force effects expansion of the liner from the spiral configuration.
BRIEF DESCRIPTION OF DRAWINGS
This invention will be better understood by reference to the following
detailed description
of the invention in conjunction with the following drawings, in which:
Figure 1 is a front elevation view of a container of the present invention;
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Figure 2 is a sectional side elevation view of the container in Figure 1,
before the metallic
particles have been inserted, and with the liner corrugations removed for
purposes of
clarity;
Figure 3 is a cross-sectional plan view of the container, taken along lines A-
A in Figure
2, after metallic particles have been inserted;
Figures 4a and 4b are cross-sectional plan views of the container, taken along
lines A-A
and C-C, respectively, in Figure 2, before the metallic particles have been
inserted;
Figure 5 is a top-perspective view of the liner, in an "unrolled condition",
of an
embodiment of the container assembled according to a method illustrated in
Figures 11 to
15;
Figure 6 is a cross-sectional view of the liner of the container illustrated
in Figure 4,
taken between the lips of the liner;
Figure 7 is a cross-sectional plan view of the container illustrated in Figure
2, where
metallic particles have been inserted and charged;
Figure 8 illustrates a typical valuing arrangement for the container of the
present
invention;
Figure 9 is a schematic illustration of an embodiment of the container of the
present
invention immersed in a liquid bath for heat transfer;
Figure 10 is a schematic illustration of an embodiment of the container of the
present
invention where the necessary heat transfer is effected by air flow generated
by a
mechanical fan; and
Figures 11 to 15 are schematic illustrations of a method of assembling an
embodiment of
the present invention;
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Figure 16 is a top perspective view of an apparatus for applying magnetic
forces during
the assembly of an embodiment of the present invention in accordance with the
method
illustrated in Figures 11 to 15;
Figure 17 is a top sectional plan view of the apparatus illustrated in Figure
16;
Figure 18 is a sectional elevation view of the apparatus illustrated in Figure
16, talcen
along lines A-A; and
Figure 19A and 19b are cross-sectional plan views of another embodiment of the
container, taken along lines A-A and C-C, respectively, in Figure 2, before
the metallic
particles have been inserted.
DETAILED DESCRIPTION
Referring to Figures 1 and 2, the present invention provides a container 10
for containing
metallic particles 12 capable of forming metal hydrides.
The interior space 20 of the container 10 receives metallic particles 12
capable of forming
metal hydrides. The metallic particles 12 are in the form of a powder. An
example of a suitable
particle size of the powder is within the range of one micron to 3000 microns.
The metallic
particles 12 must be capable of absorbing hydrogen (also known as "charging")
to effect storage
of hydrogen in the form of a metal hydride. Further, such metallic particles
12, after having
absorbed hydrogen, (in the form of a metal hydride) must be capable of
desorbing hydrogen (also
known as "discharging") upon demand from an unit operation, such as when
required for use as
a fuel in a fuel cell or in an internal combustion engine. Upon absorbing
hydrogen, the metallic
particles 12 expand, and thereby increase the volume occupied. During
desorption, the metallic
particles 12 contract, and thereby reduce the volume occupied. It is
understood that not all of the
metallic particles 12 must have necessarily absorbed hydrogen to their maximum
capacity in
order for the metallic particles 12 contained in the container 10 to be
described as being
"charged". It is also understood that, once charged, not all of the previously
absorbed hydrogen
must have necessarily been desorbed in order for the metallic particles 12
contained in the
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container 10 to be described as being "discharged". Charging of the metallic
particles 12 with
hydrogen is an exothermic process. In contrast, discharging of the absorbed
hydrogen from the
metallic particle 12 is an endothermic process.
Absorption of hydrogen by the metallic particles 12 refers to the association
of hydrogen
with the metallic particles 12. Possible mechanisms for association include:
dissolution,
covalent bonding, or ionic bonding. Dissolution describes the process where a
hydrogen atom is
incorporated in the voids of a lattice structure of a metal or intermetallic
alloy. Examples of such
metal hydrides include vanadium hydrides, titanium hydrides, and hydrides of
vanadium-
titanium alloys. An example of a covalently bonded hydride is magnesium
hydride. Examples
of ionically bonded hydrides are sodium hydride and potassium hydride. Complex
hydrides are
metal hydrides which exhibit bonding between a metalloid atom and an hydrogen
atom which is
characterized as being partially covalent and partially ionic. Examples
include sodium ala~iate
and lithium alanate.
The container 10 includes an inner surface 16 defining a container space 20
having a
container volume. The inner surface 16 includes a first end 161, a second end
162, and a
substantially tubular sidewall 163 extending between the first and second ends
161, 162 and also
extending 360° about an axis 11 of the container. The first end 161
includes a rounded shoulder
169 extending from the sidewall 163 and terminating at a nozzle 24 which
defines an aperture
241. The aperture 241 effects fluid communication between the container space
20 and the
exterior of the container 10 (such as a downstream operation, for example, a
fuel cell or internal
combustion engine, so long as such unit operation is suitably fluidly coupled
to the aperture
241). The aperture 241 functions as an inlet during charging, and as an outlet
during
discharging. Fluid communication through the aperture 241 is selectively
controlled by a valve
300 coupled to the nozzle 24. The valve 300 is operable between open and
closed conditions to
respectively effect and seal the fluid communication. The second end 162
extends from the
sidewall 163 and is closed.
A resilient liner 22 is disposed in the container 10. A void space 202 is
provided between
the liner and the inner surface 16 to accommodate expansion of the metallic
particles 12 as is
further described herein. Refernng to Figures 3 and 4, the liner 22 defines a
storage space 201 in
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the container space 20. The storage space 201 is configured to contain the
metallic particles 12.
The disposition of the metallic particles 12 typically extends up to the
rounded shoulder 169 and
up to the nozzle 24. The void space 202 is provided in the container space 20
and between the
liner 22 and the inner surface 16. The void space 202 does not contain the
metallic particles 12.
The void space 202 has a void space volume to accommodate displacement of the
liner 22, as
will be described hereafter. It is understood that the void space 202 does not
merely refer to
spaces between tightly packed metallic particles 12.
The liner 22 engages or abuts the inner surface 16 to define the void space
202 and limit
ingress of the metallic particles 12 into the void space 202 from the storage
space 201. In this
respect, the liner 22 is urged into contact with (or bears against) the inner
surface 16 to define the
void space 202 and limit the above-described ingress into the void space 202.
The first end 221
of the liner 22 bears against the second end 162 of the container, and a
second end 222 of the
liner 22 bears against the sidewall 163 or the shoulder 169, and thereby
define the void space
202.
It is understood that the engagement or abutment of the liner 22 with the
inner surface 16
does not necessarily completely prevent ingress of metallic particles 12 into
the space between
the liner 22 and the inner surface 16, although such ingress is prevented over
discrete intervals of
time. Ingress of very small quantities of the metallic particles 12 may occur
as a result of the
liner 22 becoming temporarily displaced from the inner surface 16, thereby
providing a passage
through which the metallic particles 12 can migrate into the void space 202
from the storage
space 201. Relatively insignificant ingress may also occur in the case where
an embodiment of
the container 10 is manufactured in accordance with the method described below
and illustrated
in Figures 11 to 15. In this respect, the space between the liner 22 and the
inner surface 16 may
not necessarily consist entirely of the void space 202. Also, it is understood
that the fraction of
the space between the liner 22 and the inner surface 16 consisting of the void
space 202 may
become smaller in volume during use of the container 10, due to periodic
ingress of the metallic
particles 12. In this respect, engagement or abutment of the liner 22 with the
inner surface 16 is
said to substantially prevent or limit ingress of the metallic particles 12
from the storage space
201 and into the void space 202.
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Because the void space 202 does not contain any metallic particles 12, the
void space 202
offers relatively little resistance to any displacement of the liner 22
towards the inner surface 16
in response to forces being imparted by the metallic particles 12 on the liner
22. In this respect,
the void space 202 facilitates such displacement of the liner 22 so as to, at
least in part, insulate
the container 10 from such forces and the mechanical stresses the container 10
would otherwise
experience. Such forces can arise by virtue of expansion of the metallic
particles 12 due to the
charging with hydrogen. This is aggravated by a localized increase in packing
density of the
metallic particles 12 arising from decrepitation of the metallic particles 12
(metallic particles 12
are pulverized, resulting in size reduction of the metallic particles 12) and
concentration thereof.
It is further understood that, although resilient, the liner 22 must not
necessarily return to its
exact original condition once the metallic particles contract upon the
discharging of the
hydrogen.
While the metallic particles 12 are being charged (i.e. during absorption of
hydrogen), the
space 202 contracts in response to forces imparted by the metallic particles
12 on the liner 22.
This is because the metallic particles 12 expand upon absorption of hydrogen,
causing the liner
22 to deform and become displaced in closer proximity to the inner surface 16.
With an increase
in packing density, the available space between the metallic particles 12, for
accommodating the
expansion of the metallic particles 12, decreases, resulting in stress being
applied to the liner 22.
Such stress is at least partially relieved by (i) elastic deformation of the
liner 22, and (ii)
distribution of stress by the liner 22. While the metallic particles 12 are
being discharged (i.e.
during desorption of hydrogen), the metallic particles 12 contract in volume,
thereby relieving at
least some of the forces that would have been previously being imparted by the
metallic particles
12 while the metallic particles 12 were in a charged state. As a result, and
owing to its
resiliency, the liner 22 reverses at least a portion of its deformation (that
is, deformation resulting
from the previous charging of the metallic particles 12) during discharging.
The liner 22 is disposed in the interior space 20 such that at least a portion
of the void
space 202 is disposed between the sidewall 163 and at least a portion of the
liner 22. In the
embodiment illustrated, the liner 22 has a substantially tubular form. In this
respect, the liner 22
is disposed between the sidewall 163 and the axis 11 of the container 10 and
extends 360° about
the axis 11. At least a portion of the liner 22 opposes a sidewall 163. In
this respect, the sidewall
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163 extends 360° about the axis 11 in a plane 13 perpendicular to the
axis 11, and at least a
portion of the liner 22 is disposed between the sidewall 163 and the axis 11
and extends 360°
about the axis 11 in the plane 13.
Refernng to Figures 1, 2, and 6, in the embodiment illustrated, when disposed
in the
container space 20, the liner 22 includes a sidewall 223 defining corrugations
2202. The
corrugations 2202 are defined by alternating ridges 2204 and grooves 2206,
each of the ridges
2204 and grooves 2206 extending transversely relative to the plane 13. The
ridges 2204 contact
the sidewall 163 when the liner 22 is disposed in the container space 20 of
the container 10,
thereby improving thermal communication and heat transfer between the metallic
particles 12
and the sidewall 163. The corrugations 2206 allow for space between the inner
wall 16 and the
liner 22 when the liner 22 is disposed in the container space 20. Upon
expansion of the metallic
particles 12, the metallic particles 12 apply a force to the liner 22, causing
the corrugations 2206
to flatten out (see Figure 7).
Referring to Figures 1, 4a and 4b, to bear against the container sidewall 163
or the
shoulder 169, each of the first and second ends 221, 222 of the liner 22
includes respective lips
224a, 224b projecting radially outwards from and extending about the perimeter
of the liner
sidewall 223. The lips 224a, 224b contact the inner surface 16 and effect the
engagement or
bearing of the liner 22 against the inner surface 16 for effecting the
definition of the void space
202. The engagement of the lips 224a, 224b with inner surface 16 substantially
prevents ingress
of the metallic particles 12 from the storage space 201 to the void space 202
in the manner
described above.
The liner 22 is constructed of spring steel (low carbon steel) SAE 1010
(having a tensile
strength of 50-60ksi, a yield strength of 30-40ksi, a modulus of elasticity of
about 29,000,000
psi, and a modulus of rigidity of about 11,000,000 psi). Owing to a
combination of these
features, including the corrugations 202, and geometry, the liner 22 is
configured to facilitate
stress distribution within the container 10 (relative to the case where there
is no liner 22).
The nozzle 24 is configured for fluid coupling to a conduit for effecting
delivery of
hydrogen being discharged from the metallic particles 12 from within the
container space 20 to a
downstream operation, such as a fuel cell or an internal combustion engine.
The conduit also
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facilitates supply of hydrogen to the container 10 to effect charging of the
metallic particles 12.
Figure 8 illustrates a typical valuing arrangement for the container 10. A
valve 300 is mounted
to the nozzle 24 to effect control of fluid communication between the storage
space 201 and a
downstream operation or a source of hydrogen supply. Additionally, disposed in
the nozzle 24
between the valve 300 and the interior space 20, a filter element is provided
including a 316 L
stainless steel solid sintered filter. The filter element functions as a
retainer for retaining the
metallic particles 12 in the space 20.
Heat is imparted to and dissipated from the container 10 by contacting the
container 10
with a fluid (liquid or gas, such as water or ambient air) which acts as a
heat sink or heat source
as required. The container 10 must be cooled to effect charging, and must be
heated to effect
discharging. Figure 9 illustrates the container 10 immersed in a liquid bath
400 to effect the
necessary heat transfer. Figure 10 illustrates the necessary heat transfer to
and from the
container 10 being effected by airflow, the airflow being generated by a
mechanical fan 500 and
then being directed across a heat transfer medium 510 (such as piping
containing heating or
cooling fluid) before contacting the exterior surface of the container 10.
Refernng to Figures 2, 3, 4a and 4b, a structure 18 is disposed in the space
201 and is
configured to effect or improve thermal communication between the inner
surface 16 and the
metallic particles 12 disposed within the storage space 201. The structure 18
includes a plurality
of elongated aluminum tubes 30. The tubes 30 extend from the second end 162 of
the container
and terminate just below the first end 161. The tubes 30 are isolated from the
inner surface 16
by the liner 22, and thermally communicate with the inner surface 16 through
the liner 22. In
relation to the tubes 30, the metallic particles 12 occupy the space within
the tubes 30 as well as
the space between the tubes 30. The metallic particles 12 also occupy the
space witlun the first
end 161 of the container 10. To facilitate heat transfer between the metallic
particles 12 and the
inner wall 16, the tubes 30 are tightly packed and in direct physical contact
with the liner 22 to
facilitate heat transfer between the liner 22 and the metallic particles 12.
The tightly packed
configuration of the tubes 30 urges the liner 22, and particularly the lips
224a, 224b, into contact
engagement with the inner surface 16.
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The tubes 30 play a role in containing a portion of the expansion forces of
the expanding
metallic particles 12, thereby reducing stresses on the liner 22 and, thus,
the container 10. In this
respect, the tubes reduce the influence of the expanding metallic particles 12
on the container 10.
The tubes 30 also play a role in limiting the creation of differences in
localized packing
density of the metallic particles 12 within the storage space 201. This is
because the tubes 30
function as physical barners, limiting migration of the metallic particles.
To facilitate migration of hydrogen gas during charging and discharging, each
of the
tubes 30 can include a plurality of very small apertures or perforations 301.
Preferably, these
apertures or perforations have a maximum diameter of 1/32" or smaller. Such
apertures are
small enough to allow the migration of the hydrogen gas, but prevent the
metallic particles 12
within the tubes 30 from migrating outside of the tubes 30 and thereby
exerting additional forces
on adjacent materials or surfaces during expansion.
At least one of the plurality of tubes 30 can be in the form of a solid
sintered filter
cylinder that would provide a permeable solid to assist in the absorption and
desorption of
hydrogen gas while not allowing the migration of metallic particles 12. In one
embodiment, the
solid sintered filter cylinder comprises 316 L stainless steel.
Refernng to Figures 19a and 19b, in one embodiment, at least one of the
plurality of
tubes 30 includes a fluid passage tube 3001 disposed within the at least one
tube 30 in a
substantially concentric relationship relative to the at least one tube 30.
The fluid passage tube
3001 contains substantially no metallic particles 12. The metallic particles
12 occupy the space
3003 between the tubes 30 and 3001. The fluid passage tube 3001 extends
substantially along
the complete length of the tube 30. The fluid passage tube 3001 is configured
to provide a
relatively low pressure fluid passage for effecting communication of hydrogen
gas between the
aperture 241 and at least the metallic particles 12 between the tubes 30 and
3001.
A method of assembling an embodiment of the container 10 will now be
described. A
container 10 is provided, having a length of 355 mm defined by the distance
between its terminal
ends identified by reference numerals 101, 102 in Figure 2, an outside maximum
diameter of 89
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ruin, and a wall thickness of 3.68 mm, and is constructed of aluminum SAE 6061-
T6. The liner
22 is then inserted into the container space 20 through the aperture 241 of
the nozzle 24.
Referring to Figure 5, the liner 22 is provided in the form of a 273 mm x 268
mm sheet
having a thickness of 0.15 mm, for co-operation with the container 10 having
the dimensions
described above. The liner 22 is further defined by first and second side
edges 225, 226. Lips
224a, 224b are formed at the first and second ends 161, 162, respectively,
without corrugations.
The liner 22 is constructed of spring steel (low carbon steel) SAE 1010.
Referring to Figure 11, to enable the liner to be inserted, one of the side
edges 225, 226
of the liner 22 is inserted into a groove 702 provided in a mandrel 700. With
one of the side
edges 225 or 226 disposed in the groove 702, the liner 22 is then tightly
rolled around the
mandrel 700 by hand by a human operator. The mandrel 700 is in the form of a
rod-like
structure with a cylindrical surface and functions as a means for facilitating
rolling of the liner
22. By rolling the liner 22 around the mandrel 400, the liner 22 is
manipulated to effect overlap
of the first and second side edges 225, 226. Preferably, the liner 22 is
manipulated into a spiral
configuration and maintains overlap of the first and second side edges 225,
266 as the liner 22
becomes positioned in the container 10 in the manner described below.
Refernng to Figure 12, with the liner 22 tightly wound around the mandrel 700
and
maintained (i.e. pressed) in this condition by the hand of a human operator,
the mandrel 700,
with the liner 22, is inserted into the container space 20 through the nozzle
24. Once
approximately 50% of the length of the liner 22 has been inserted through the
nozzle 24, forces
applied to maintain the liner 22 in a rolled condition against the mandrel 700
can be released as,
in this position, the liner is not capable of becoming released from within
the container space 20
upon the release of the liner 22 from the mandrel 700. Once the above-
described forces
maintaining the liner 22 rolled against the mandrel 700 are removed, the liner
22 assumes a
radially expanded condition about the mandrel 700 (Figure 13). The mandrel 700
is then
removed from the container space 20 through the nozzle 24. The liner 22 is
pushed into the
container space 20 (see Figure 14), and expands further in the radial
direction once not
constrained by the nozzle 24.
CA 02523873 2005-10-26
WO 2004/097286 PCT/CA2004/000646
16
With the liner 22 disposed in the container space 20, magnetic forces are
applied to the
container 10 to effect positioning of the liner against the inner wall 16 of
the container 10. In
this respect, the magnetic forces attract the liner 22 towards the inner wall
16 (see Figure 15).
An apparatus 600 for applying the above-described magnetic forces is
illustrated in
Figures 16-18. . The apparatus 600 is a plastic tube 602 of ultra high
molecular weight
polyethylene defining a passage 604 for receiving the container 10. The tube
602 has a length
of 311 mm, an outside diameter of 162 mm, and an inside diameter of 89 rnm, to
accommodate
an embodiment of the system 8 being assembled in accordance with the method
presently being
described. Recesses 606 are provided in the exterior surface of the plastic
tube for receiving
magnetic material 608. Magnetic material 608 is provided for effecting the
above-described
magnetic force. An example of suitable magnetic material 608 is a rare earth
magnetic
(neodymium iron boron) manufactured by Dura Magnetics, Inc. of Sylvania, Ohio,
U.S.A. (see
www.durarnag.com). Once disposed in the passage 604 of the plastic tube 602,
the magnetic
forces imparted by the magnetic material 608 urge the liner 22 against the
inner surface 16 of the
container 10.
While the magnetic forces are continuing to be applied to the liner 22, the
tubes 30 are
inserted into the container space 20 through the nozzle 24. With the container
10 having the
dimensions specified above, twenty-eight tubes 30, each having an outside
diameter of 12.7 mm,
a wall thickness of 0.8 mm, and a length of 263 mm, are inserted into the
container space 20.
Once all of the thirty-one tubes 30 are disposed in the container space 20,
tubes 30 are disposed
in a tightly packed configuration and are pressing liner 22 against the inner
surface 16 of the
container 10. As a result, the magnetic force being applied by the magnetic
material 608 is no
longer required to urge the liner 22 against the inner surface 16 and thereby
effect its disposition
against the inner wall 16 (i.e., bearing of the lips 224a, 224b against the
inner wall 16). The
container 10 can now be removed from within the passage 604 of the plastic
tube 302.
In this condition, the lips 224a, 224b of the liner 22 engage the inner
surface 16 for (i)
defining a storage space 201 configured to contain the metallic particles 12
and also (ii) for
defining a void space 202 configured to contract as the metallic particles 12
expand upon
absorption of hydrogen, such that the engagement of the liner 22 to the inner
surface 16
CA 02523873 2005-10-26
WO 2004/097286 PCT/CA2004/000646
17
substantially prevents or limits ingress of the metallic particles 12 into the
void space 202 from
the storage space 201. At this point, an embodiment of the container 10
assembled in accordance
with the just described method substantially assumes the condition illustrated
in Figure 2. While
the liner 22 is in this condition, the storage space 201 of the container 10
is filled with the
metallic particles 12 through the nozzle 24. The container 10 continues to be
filled with the
metallic particles 12 until the level of the metallic particles 12 in the
storage space 12 reaches the
nozzle 24.
It is understood that, by virtue of the assembly of an embodiment of the
container 10 by
the method above-described, the engagement of the liner 22 to the inner
surface 16 substantially
prevents ingress of the metallic particles into the void space 202 and does
not completely prevent
ingress into the void space 202. This is because, even after the tubes 30 are
inserted into the
container space 20 and thereby press against the liner 22, and particularly
press the first and
second ends 221, 222 against the inner surface 16 while simultaneously
pressing portions of the
liner 22 at opposite edges 225, 226 against each other to effect overlap of
edges 225, 226, a very
small space or spaces between the liner 22 and the inner surface 16 continue
to exist and define a
potential passage or passages for ingress of metallic particles 12 into the
void space 202 from the
storage space 201. However, where the metallic particles 12 are sufficiently
large (e.g. where
77% of the metallic particles 12 have a particle size greater than 150
microns, and more
particularly where 20% are within the range of 1000 to 2800 microns, 23% are
within the range
of 500 to 1000 microns, 34% are within the range of 150 microns, and the
remainder under 150
microns), such space or spaces, defined in an embodiment of the container 10
created by the
method described above, are sufficiently small so that any periodic ingress is
relatively
insignificant. In this respect, such ingress can also be characterized as
being substantially
prevented or limited.
Although the disclosure describes and illustrates preferred embodiments of the
invention,
it is to be understood that the invention is not limited to these particular
embodiments. Many
variations and modifications may occur to those skilled in the art within the
scope of the
invention. For definition of the invention, reference is to be made to the
appended claims.
