Apparatus for cooling individual sources of heat on a printed circuit board assembly

Abstract

The present invention provides an apparatus for cooling individual sources of heat disposed at locations on one or more printed circuit board (PCB) assemblies. The apparatus includes a bladder having a plurality of apertures positioned to substantially align with and provide an independent air stream to the location of each individual source of heat, thereby providing targeted forced convection cooling to each individual heat source. The apparatus further includes a source of forced air directed to inflate the bladder and thereby create a flow of air into the bladder that egresses through the plurality of apertures. The bladder has overall dimensions such that when fastened in an arrangement that substantially aligns the apertures with heat sources, the bladder, once inflated, extends over the one or more PCB assemblies in which the heat sources are located and causes substantially uniform air temperature and flow of air egressing through individual apertures.

Description

APPARATUS FOR COOLING INDIVIDUAL SOURCES OF HEAT ON A PRINTED CIRCUIT BOARD ASSEMBLYFIELD OF THE INVENTION

[0001] The present invention relates to an apparatus for cooling individual sources of heat on a printed circuit board assembly. In particular, the present invention relates to a cooling apparatus including a bladder configured to be inflated to create an air flow that egresses through a plurality of apertures associated with the bladder which are positioned to substantially align with, and provide independent streams of air to, the location of each individual source of heat.BACKGROUND OF THE INVENTION

[0002] A printed circuit board assembly, or PCB assembly, is a well-known apparatus for supporting electronic components and means for interconnecting the electronic components to one another in an electronic circuit. In particular, a PCB assembly typically includes electronic components having terminals which are electrically connected to the PCB by soldering the terminals to conductors (eg. traces, pads, etc) responsible for creating electrical connections between the components. Such electronic components typically include capacitors, resistors, inductors, diodes and semi-conductor devices such as microprocessors.

[0003] PCB assemblies are used in a variety of different electronic products and applications. One particular application discussed herein relates to PCB assemblies configured for use with energy storage systems and in particular, energy storage cell units (also known as cell stacks). However, there are numerous additional applications in which PCB assemblies are utilised, including but not limited to, medical devices, lighting, consumer electronics, industrial equipment, automotive components, aerospace components, maritime applications, security equipment, telecommunications equipment, and military and defence applications.

[0004] Most components on a PCB assembly will generate heat, and transistors in particular generate and dissipate significant amounts of heat due to electrical current flowing through them. A heat generating transistor commonly used on a PCB assembly is a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). There are problemswhen components such as MOSFETs heat and dissipate substantial amounts of thermal energy including, but not limited, to disruption in electrical circuits (eg. due to solder separation), oxidation of components, loss of structural integrity, etc, all of which can affect the performance of the PCB assembly. In extreme circumstances, PCB components can become so hot that they cause the PCB assembly to fail and malfunction beyond repair. Accordingly, there is a need to cool sources of heat on PCB assemblies.

[0005] Cooling techniques known to the Applicant, including mounting one or more heat sinks to components on the PCB assembly such that the heat sink is attached to one or more heat generating components for the purpose of absorbing and dissipating heat, can be effective but add expense, complexity and weight to the PCB assembly.

[0006] An alternative known method of cooling is to provide airflow over the entire PCB assembly from a source of cool air. The problem with such techniques is that as the air stream passes each component to be cooled, the cooling air temperature increases as the air stream travels from the source of air across PCB components. This results in the last components in the air path receiving significantly warmer air as compared with the first components that receive cooling air in the flow path. Accordingly, there is a need for a cooling apparatus that provides air to individual heat sources at a substantially uniform temperature irrespective of the location of each heat source on the PCB assembly and / or the location of the source of air.

[0007] Another problem that arises in view of PCB assemblies being manufactured in many different shapes and sizes and having a variety of different heat source locations, is that existing cooling techniques are not suitable to inexpensively adapt for use on PCB assembly configurations. Accordingly, there is also a need for a cooling apparatus capable of inexpensive adaptation and manufacture and / or configuration such that the cooling apparatus is capable of being used across a plurality of different PCB assembly shapes and sizes, and different component arrangements.

[0008] Additional problems associated with existing PCB assembly cooling techniques known to the Applicant include, but are not limited to, difficulties associated with fastening cooling apparatus to PCB assemblies, and air leakage when attempting to direct an air stream to cool heat sources on PCB assemblies.

[0009] The apparatus of the present invention seeks to address or at least ameliorate some of the above identified problems.

[0010] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any suggestion, that the prior art forms part of the common general knowledge or would be obvious to a relevant skilled addressee.SUMMARY OF THE INVENTION

[0011] In one aspect, the present invention provides an apparatus for cooling one or more individual sources of heat disposed at locations on one or more printed circuit board (PCB) assemblies, the apparatus including a bladder including a plurality of apertures positioned to substantially align with and provide an independent air stream to the location of each individual source of heat, thereby providing targeted forced convection cooling to each individual heat source, one or more sources of forced air directed to inflate the bladder and thereby create a flow of air into the bladder that egresses through the plurality of apertures, wherein the bladder has overall dimension such that when fastened in an arrangement that substantially aligns the apparatus with heat sources, the bladder, once inflated, extends over the one or more PCB assemblies in which the heat sources are located, with the inflated bladder causing substantially uniform cooling air flow through each aperture by compensating for any air flow variations with respect to incoming air flow into the bladder and achieving substantially uniform cooling arising from uniform air temperature and flow of air egressing through the individual apertures.

[0012] In an embodiment, the air directed to inflate the bladder is ambient air. Alternatively, the air directed to inflate the bladder is cooled to a temperature below ambient.

[0013] In an embodiment, the flow of cooling air to each heat source egressing through each bladder aperture is effected by a bladder having a nominal cross-sectional area in the locality of the plurality of apertures that is sufficient, as compared with the collective area of the apertures, to achieve substantially uniform air flow through apertures of substantially similar dimensions despite variations to the flow of air into the bladder.

[0014] In an embodiment, the nominal cross-sectional area of the inflated bladder is two or more times the collective area of the apertures formed in the bladder.

[0015] In a particular embodiment, the nominal cross-sectional area of the inflated bladder is approximately three times the collective area of the apertures formed in the bladder.

[0016] In an embodiment, inflation of the bladder, once fastened and inflated, causes the bladder to hover over the one or more PCB assemblies on which the heat sources are located. In one particular embodiment, the bladder is fastened to the one or more PCB assemblies in a configuration that causes the bladder to hover over the one or more PCB assemblies.

[0017] In an embodiment, the bladder is fastened to the one or more PCB assemblies in a configuration that causes the bladder to hover over the one or more PCB assemblies by using one or more fasteners that enable a distance to be maintained between the one or more PCB assemblies and the bladder once inflated.

[0018] In an embodiment, the one or more fasteners are rivets that each include a head portion disposed inside the bladder and a stem portion that extends through coaxial fastening apertures associated with the bladder and the one or more PCB assemblies.

[0019] In an embodiment, each of the one or more fasteners further includes a spacer disposed between the fastener head portion and the one or more PCB assemblies, and include a height that enables the bladder to hover a distance above the one or more PCB assemblies that substantially corresponds with the height of the spacer. In one embodiment, the fasteners are pre-assembled with the bladder.

[0020] In an embodiment, the formation of bladder apertures during manufacture of the bladder includes formation of fastening apertures through which rivets are configured to extend.

[0021] In an embodiment, the formation of the bladder apertures and fastening apertures is achieved using a datum method, wherein the fastening apertures which align with bladder fixation points on the one or more PCB assemblies are used as reference points to determine the location of each bladder aperture, thereby ensuring that each bladder aperture substantially aligns with the location of each source of heat on the one or more PCB assemblies once the bladder is inflated.

[0022] In an embodiment, the one or more PCB assemblies and the bladder include co-operating fastening means. In one embodiment, the co-operating fasteningmeans includes fastening apertures associated with the bladder configured to engage with hooks included in the one or more PCB assemblies during manufacture thereof.

[0023] In an embodiment, the bladder fastening apertures extend through the bladder. Alternatively, the bladder fastening apertures may be formed in tabs attached (eg. welded) to the bladder.

[0024] In an embodiment, the bladder is made of one or more of a flexible material (ie. a material having flexible properties), plastic material, or transparent material.

[0025] In an embodiment, the one or more sources of forced air includes a blower. In one embodiment, the blower is located inside the bladder wherein the bladder is sealed around an intake of the blower. In an alternative embodiment, the blower is mounted externally to the bladder and the bladder is sealed around an outlet of the blower.

[0026] In an embodiment, when the bladder includes a blower located inside the bladder, the bladder is formed from material including one or more open ends that are sealed to form sealed bladder ends (eg. using heat sealing and / or laser welding), wherein one or more of the bladder ends includes at least one inlet aperture to accommodate incoming airflow from the blower.

[0027] In an embodiment, the inlet aperture equal to or larger than a side profile dimension of the blower to enable the blower, once the seal between the bladder and blower inlet is released, to be physically manipulated and removed through the inlet aperture.

[0028] In an embodiment, the blower further includes one or more of a fitted filter or debris guard at the intake of the blower, and (when the blower is located inside the bladder) a gasket made of open cell foam that seals the bladder and the intake of the blower. Whilst a filter is beneficial to prevent debris from entering the bladder, air flow into the bladder may vary when debris obstructs air flow. However, the relative size of the cross sectional area of the bladder as compared with the collective area of the apertures is preferably such that variations to air flow egressing through apertures is ameliorated in instances where debris collected by the air blower filter cause variations to the incoming air flow into the bladder.

[0029] In an embodiment, the bladder is shaped and / or configured to provide cooling for a single PCB assembly, or for two or more PCB assemblies (eg. multiple cell stacks).

[0030] In an embodiment, the configuration of the bladder is such that the cross- sectional area of the bladder is substantially uniform along the length, and / or across the width, of the bladder. In another embodiment, the configuration of the bladder has a non- uniform cross sectional area along the length and / or the width of the bladder.

[0031] In an embodiment, the cross-sectional dimension of the bladder when inflated is substantially circular, square, rectangular, oval or has a substantially concertinaed bellow shape, although other cross-sectional shapes are possible.

[0032] In an embodiment, the shape of each bladder aperture includes one or more of substantially circular, square, oval, rectangular, and star shaped. In one embodiment, the shape of each bladder aperture varies according to the particular type of air flow required for individual heat sources (eg. star shaped apertures produce more turbulent air flow as compared with circular apertures).

[0033] In an embodiment, the size of each bladder aperture varies depending upon the particular air flow rate and / or air flow velocity required for individual heat sources (eg. larger aperture areas result in a decreased flow velocity as compared with the flow velocity through a smaller area aperture).

[0034] In another aspect, the present invention provides one or more PCB assemblies including an apparatus for cooling one or more individual sources of heat disposed at locations on the one or more PCB assemblies, the apparatus configured in accordance with any one or more of the preceding statements.

[0035] In yet another aspect, the present invention provides a battery cell stack including one or more PCB assemblies configured in accordance with any one or more of the preceding statements.

[0036] In a yet further aspect, the present invention provides a battery storage system including a plurality of battery cell stacks each configured in accordance with any one or more of the preceding statements.BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Features of the present disclosure are illustrated by way of example and not limited in the following Figure(s), in which like numerals indicate like elements, in which:

[0038] Figure 1 illustrates a perspective view, with some hidden features depicted in broken lines, of an apparatus including a bladder for cooling individual sources of heat on a plurality of printed circuit board (PCB) assemblies according to an embodiment of the present invention;

[0039] Figure 2 illustrates an enlarged view of a single PCB assembly of Figure 1 , and a further enlarged view of the individual sources of heat located on the PCB assembly and apertures in the bladder which are aligned with and provide independent air streams to each individual source of heat;

[0040] Figure 3 illustrates an end view of the apparatus of Figure 1 when the bladder is inflated, wherein the bladder associated with the apparatus is fastened to the PCB assembly using rivets and associated spacers to enable a spaced apart distance to be maintained therebetween in accordance with an embodiment of the present invention;

[0041] Figure 4A illustrates different views of an alternative embodiment in which the PCB assembly includes hooks and the air bladder, which is shown in a deflated state, includes fastening apertures for engaging with the hooks, wherein each fastening aperture extends through a tab associated with the bladder;

[0042] Figure 4B illustrates different views of a further alternative embodiment in which the PCB assembly includes hooks and the air bladder, which is shown in a deflated state, includes fastening apertures for engaging with the hooks, wherein each fastening aperture extends through the bladder;

[0043] Figure 5 illustrates different views of a blower according to an embodiment in which the blower is located inside the bladder, which is again shown in a deflated state, and sealed around an intake of the blower, wherein the blower further includes a gasket configured to act as a filter as well as a seal between the bladder and the intake of the blower; and

[0044] Figure 6 illustrates a top view of a cooling apparatus according to an embodiment in which the cooling apparatus is configured to provide cooling for two PCB assemblies associated with two cell stacks.DETAILED DESCRIPTION OF EMBODIMENT(S) OF THE INVENTION

[0045] For simplicity and illustrative purposes, the present disclosure is described by referring to embodiment(s) thereof. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be readily apparent, however, that the present disclosure may be practiced without limitation to these specific details. In other instances, some features have not been described in detail to avoid obscuring the present disclosure.

[0046] According to an embodiment, the present invention includes an apparatus (10) for cooling one or more individual sources of heat (20) (eg. heat generating components including transistors such as MOSFETs and the like) disposed at locations on one or more PCB assemblies (30). According to the embodiment shown in Figure 1 , the apparatus (10) includes a bladder (40) in a deflated state having a plurality of apertures (50) extending through an underside thereof which substantially align with and provide independent air streams to the location of each individual source of heat (20). In this way, when the bladder (40) is inflated, air will egress through the apertures and provide targeted forced convection cooling to each individual heat source (20).

[0047] In the embodiment shown, the air inside the bladder (40) is sourced from one or more blowers (60) configured to direct air to inflate the bladder (40) and thereby create a flow of air into the bladder (40) that egresses through the plurality of apertures (50). The bladder (40) has an overall dimension such that when fastened to the PCB assemblies (or an alternative support), the apparatus (10) is caused to substantially align with the heat sources (20). Accordingly, the bladder (40) extends over the PCB assembly (30) in which the heat sources (20) are located and causes substantially uniform cooling air to flow through each aperture (50) to thereby cool each heat source (20) at substantially uniform air temperature. This is achieved, at least in part, by the overall dimension of the bladder (40) compensating for any air flow variations with respect to variations to the incoming air flow into the bladder (40).

[0048] It will be appreciated that when using an air bladder (40) of substantially flexible material such as plastic, and further, using a blower (60) as a source of cooling air in the manner described above, there may be variations in air flow that result from the use of the blower (60) forcing air into a confined space. For example, variations in air flowinto the bladder (40) may be caused due to back pressure once the bladder (40) is fully inflated, leakages that may occur requiring more air to be forced into the bladder (40) to reinflate, voltage fluctuations, debris build up on the air filter in-take (170), etc.

[0049] The skilled addressee will appreciate that by providing an air stream to each individual heat source in a manner that achieves substantially uniform cooling, components of the PCB assembly (30) that generate heat will be individually cooled in a consistent manner irrespective of the location of the component on the PCB assembl(ies) (30) and / or the location of the source of air (60). Further, this cooling is achieved in a manner that does not involve significant expense, complexity and weight since the bladder (40) may be made of an inexpensive material (eg. plastic) and manufactured in an efficient and inexpensive manner (eg. by sealing open ends of a plastic tube from which the bladder is to be formed using heat sealing and / or laser welding).

[0050] The apertures (50) may be easily formed in substantial alignment with the sources of heat (20) associated with the PCB assembly (30) based on one or more of the bladder fixation points on the PCB assembly (30) being used as reference points, as described in greater detail below.

[0051] It will be appreciated that once the bladder (40) is inflated, it will have a nominal cross-sectional area in the locality of the plurality of apertures (50) that is sufficient, as compared with the collective area of the apertures (50), to achieve substantially uniform air flow through apertures (50) of substantially similar dimensions, despite variations to the flow of air into the bladder (40). In this regard, it will be appreciated that the cross-sectional area of the bladder (40) may vary depending on the shape of the bladder.

[0052] If the bladder is square / rectangular shaped, for example, the cross- sectional area of the bladder along the length and / or width thereof will be substantially uniform. However, when the bladder (40) includes a circular cross-sectional area, for example, it will be appreciated that the bladder (40) will likely have a non-uniform cross- sectional area along a length and / or width thereof. The same will apply for other cross- sectional shapes, including for example when the bladder is tapered along a length and / or width thereof. Provided apertures (50) can be formed in the surface of the bladder (40) facing the PCB assembly (30) in appropriate locations to enable the flow of air throughthe plurality of apertures (50) to individual heat sources (20), any suitable bladder shape and / or size may be implemented.

[0053] For example, the bladder (40) may include a substantially circular cross- sectional dimension when inflated. In alternative embodiments, the bladder (40) may include other cross-sectional shapes including, but not limited to, square, rectangular, triangular, oval or concertinaed bellow shape.

[0054] It will also be appreciated that where a particular bladder shape / size is such that the flow of air through the bladder using a single source of air is insufficient, more than one source of forced air (eg. two or more blowers) may be utilised.

[0055] It is to be further understood that the shape of the apertures (50) may also vary depending upon the particular application in which the apparatus (10) is used, and the shape of individual apertures associated with a single bladder may also vary. For example, the bladder apertures (50) may include one or more of circular, oval, rectangular, and star shaped apertures. The shape of each aperture (50) may also vary according to the particular type of air flow required for individual heat sources (20), with larger aperture areas resulting in a decreased flow velocity as compared with the flow velocity through a smaller area aperture. It may also be advantageous to provide a more turbulent air flow to some heat sources (20) as compared with others, and providing apertures of particular shapes may facilitate more turbulent air flow including, for example, a star shaped aperture (not shown) which would produce more turbulent air flow as compared with a circular aperture.

[0056] It will be understood that provided the nominal cross-sectional area of the bladder (40) in the locality of the plurality of apertures (50) is sufficient, as compared with the collective area of the apertures (50), substantially uniform air flow through apertures of substantially similar dimension will be achieved despite variations to the flow of air into the bladder (40). In this way, any bladder and / or aperture size and shape may be selected to suit any particular application. In the embodiment shown in the accompanying Figures, the nominal cross-sectional area of the inflated bladder (40) is approximately three times the collective area of the apertures (50) formed in the bladder (40). However, the present invention is not limited to the use of a bladder having a nominal cross-sectional area approximately three times the collective area of the apertures (50). For example, thecross-sectional area may be less than (eg. two) or more than three (eg. four or five) times the collective area of the apertures (50) depending on factors such as size / shape restrictions on the bladder, the number / power of blowers used, etc.

[0057] The bladder (40) is shown in the accompanying drawings as being directly fastened to the PCB assemblies (30) in a manner that causes the bladder (40) to hover, once inflated, over the PCB assemblies (30) on which the heat sources (20) are located, as most clearly shown in Figure 3. However, as mentioned above, there is no requirement for the bladder (40) to be directly fastened to the PCB assemblies (30) since the bladder (40) could be caused to hover over the PCB assemblies (30) by being supported and / or fastened in an alternative configuration. In other words, the bladder (40) needs to be aligned to the PCB assembly (12) but not necessarily fastened directly to it. Figures 4A and 4B illustrate how the bladder (40) may be fastened to the PCB assemblies (30) according to additional embodiments of the present invention.

[0058] In the embodiment shown in Figures 1 -3, the one or more fasteners are fir tree (also known as push-in) rivets (70) that each include a head portion (80) disposed inside the bladder (40) and a stem portion (90) that extends through co-axial fastening apertures (100) extending in alignment through each of the bladder (40) and PCB assembly (12), as shown most clearly in Figure 3. In this embodiment, the stem portion (90) includes outwardly extending barbs, however, any fastening means suitable for causing the rivet to engage with an aperture in the PCB assembly can be used.

[0059] Figure 3 also clearly shows the use of spacers (110) disposed between the fastener head portions (80) and the PCB assemblies (30). The height of the spacers (110) enables the bladder (40) to hover a distance above the PCB assemblies (30), and it will be appreciated that, in this embodiment, the height of the bladder (40) relative to the PCB assembly (30) substantially corresponds with the height of the spacer (1 10). However, as will become apparent, a spaced apart distance between the bladder (40) and PCB assemblies (30) can be achieved such that inflation of the bladder causes the bladder to hover a spaced apart distance from the PCB assembly without the use of directly fastened rivets or spacers.

[0060] The co-axial fastening apertures (100) associated with the bladder (40) and the PCB assemblies (30) include apertures that are formed in the bladder (40) for thepurpose of receiving the stem portions (90) of rivets (70). It is to be understood that such rivets may be pre-assembled with the bladder (40). Further, the formation of the bladder apertures (50) during manufacture of the bladder (40) may include formation of the fastening apertures (100) through which rivets or other fastening means (70) are configured to extend.

[0061] In a particular embodiment, the formation of the bladder apertures (50) and the bladder fastening apertures (100) is achieved using a datum method. This involves aligning the fastening apertures (100) associated with the bladder (40) with bladder fixation points on the PCB assembly (12) (ie. the fastening apertures (100) extending through the PCB assembly (12)). In this way, the fastening apertures (100) are used as reference points to determine the location of each bladder aperture (50). This ensures that each bladder aperture (50) substantially aligns with the location of each source of heat (20) on the PCB assembly (30) once the bladder (40) is inflated.

[0062] In the alternative embodiment shown in Figure 4A, which shows an assembled bladder (40) and PCB assembly (30) (as well as the PCB assembly (30) and bladder (40) as individual components there beneath), it will be appreciated that the PCB assembly (30) and the bladder (40) include co-operating fastening means. The cooperating fastening means include tabs (120) associated with the bladder (140) which each include a bladder fastening aperture (130), and correspondingly positioned hooks (140) associated with the PCB assembly (30).

[0063] In the additional alternative embodiment shown in Figure 4B, again an assembled bladder (40) and PCB assembly (30) is illustrated along with the PCB assembly (30) shown as an individual component there beneath. It will be appreciated in this embodiment that the PCB assembly (30) includes the same hooks (140) as the embodiment shown in Figure 4A. However, the bladder (40) no longer includes tabs (120) and instead, the fastening apertures (150) associated with the bladder (40) of Figure 4B extend through the bladder (40), similar to the apertures (50) through which air egresses to cool the sources of heat (20).

[0064] In both of the embodiments shown in Figures 4A and 4B, the PCB hooks (140) (which may be routed to the edge of the PCB assembly (30)) may be passed through the fastening apertures (130 / 150) in the bladder (40) for the purpose of retainingthe bladder (40). As shown in the end view of Figure 4A, the fastening apertures (130) associated with the tabs (120) are configured to be placed over the hooks (140) to engage therewith, and the use of tabs (120), which in the embodiment shown are effectively plastic flaps that extend outwardly from the surface edge of the bladder (40), provide a means by which to space the bladder (40) apart from the PCB assembly (30). As shown in the end view of Figure 4B, when the fastening apertures (130) extend through the bladder (40) the fastening does not serve to provide a spaced apart distance between the bladder (40) and the PCB assembly (30). However, it will be appreciated that once the bladder (40) is inflated the area of the bladder (40) which houses the apertures (50) will likely be provided with sufficient lift to ascend to a short distance above the PCB assembly (30).

[0065] It will therefore be appreciated that the embodiment shown in Figures 4A and 4B represent examples of how the bladder (40) may be attached to the PCB assembly (30) without the use of any fasteners such as rivets (70) whilst still ensuring a spaced distance of the bladder from the PCB assembly surface when inflated. Whilst some leakage may occur through the apertures (150) of Figure 4B, it is envisaged that such leakage will be negligible relative to the overall mass flow of the system.

[0066] The source of forced air into the bladder (40) may include one or more blowers (60) and in the embodiments shown in the Figures, a single blower (60) is used. However it is to be understood that multiple blowers could be used, if required. It will also be appreciated that the blower (60) may be mounted to the bladder (40) such that the blower (60) is located inside the bladder (40), as shown in Figure 5, or externally of the bladder (40) (not shown). In either configuration, the blower (60) will be attached to the bladder (40) in a sealed configuration to prevent, or at least minimise, leakage of air through the bladder inlet aperture (160).

[0067] In the embodiment shown in Figure 5 where the blower (60) is located inside the bladder (40), the bladder (40) includes an inlet aperture (160) that is at least equal to, or larger than, a side profile dimension of the blower (60) to enable the blower (60) to be turned on its side and inserted through the inlet aperture (160) during assembly of the apparatus (10). By having an inlet aperture (60) dimensioned as detailed, it will be appreciated that if the blower (60) requires removal for any reason (including, for example, repair or replacement), once the seal between the bladder (40) and blower (60)is released, the blower (60) may be turned on its side and removed through the inlet aperture (160).

[0068] Also shown in Figure 5 is a debris guard (170) located externally of the bladder (40) at the intake of the blower (60) which is housed inside the bladder (40). A filter that prevents debris (particles) from entering into the blower (60) may form part of the debris guard (170) or may be a separate component such as the filter gasket (180) shown in Figure 5.

[0069] Accordingly, in the particular configuration shown in Figure 5, the filter gasket (180) disposed on the inside of the bladder (40) extends between the intake of the blower (60) and the edge of the bladder (40) that defines the inlet aperture (160), thereby acting not only as a filter but also as a seal by sealing the bladder (40) and the intake of the blower (60). Such a gasket (180) may be made of open cell foam or similar filtering material. In other words, by clamping the blower (60) and the debris guard (170) with a filter gasket (180) therebetween, the compressed foam material associated with the gasket (180) provides an effective seal whilst also providing the required filtering of particles and any additional matter which may interrupt the operation of the blower (60) or give rise to other problems such as causing variations to the incoming air flow into the bladder (40).

[0070] If a filtering gasket is used for preventing fine particles from entering the blower (60), the debris guard (170) may include a coarse filter for preventing larger particles and debris from entering through aperture (160). It will be appreciated that the filtering components used in association with the blower (60) may be configured differently to that illustrated and described herein and other variations will be possible.

[0071] In the event that particles are caught by the debris guard (170) and / or filtering gasket (180), the relative size of the cross-sectional area of the bladder (40) as compared with the collective area of the apertures (50) is such that variations to the incoming air flow into the bladder caused by such debris will be compensated by the relative size of the cross-sectional area of the bladder (40) as compared with the collective area of the apertures (50). This represents an example of the cross sectional area of the inflated bladder (40) ameliorating variations to the incoming air flow.

[0072] Figure 6 shows two PCB assemblies (30) configured for use with an energy storage system that comprises two energy storage cell units (190). A single bladder (40) is utilised in the embodiment shown in Figure 6 to provide targeted forced convection cooling to each individual heat source (20) associated with each of the PCB assemblies (30). In this regard, the bladder (40) includes apertures located on opposing sides of the bladder rather than just an underside as previously described. The bladder (40) has an overall dimension and position that enables the apparatus (10) to be aligned with the heat sources (20) such that a single bladder (40) extends over both the PCB assemblies (30) in which the heat sources (20) are located.

[0073] It is to be understood that additional variations are possible, including for example the use of a single bladder (40) to accommodate more than two PCB assemblies (30) as shown in the embodiment of Figure 1 . In another example, a circular cross-section bladder could be utilised to provide cooling for four PCB assemblies (30) arranged in a square arrangement around the circular cross-section bladder to thereby service four energy storage cell units. The same circular cross-sectional configuration could also be utilised when there are three PCB assemblies (12) arranged in a triangular configuration around the bladder. It will be appreciated that the bladder (40) may be manufactured in a wide variety of different shapes and sizes to accommodate a wide variety of PCB assembly configurations and heat source arrangements.

[0074] It will be appreciated by persons skilled in the relevant field of technology that numerous variations and / or modifications may be made to the invention as detailed in the embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all aspects as illustrative and not restrictive.

[0075] Throughout this specification and claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to mean the inclusion of a stated feature or step, or group of features or steps, but not the exclusion of any other feature or step, or group of features or steps.

Claims

AMENDED CLAIMS received by the International Bureau on 29 January 2025 (29.01 .2025)

1. An apparatus for cooling one or more individual sources of heat disposed at locations on one or more printed circuit board (PCB) assemblies, the apparatus including: a bladder including a plurality of apertures positioned to substantially align with and provide an independent air stream to the location of each individual source of heat, thereby providing targeted forced convection cooling to each individual heat source; one or more sources of forced air directed to inflate the bladder and thereby create a flow of air into the bladder that egresses through the plurality of apertures; wherein the bladder has overall dimensions such that when fastened in an arrangement that substantially aligns the apertures with heat sources, the bladder, once inflated, extends over the one or more PCB assemblies in which the heat sources are located; and the inflated bladder causing substantially uniform cooling air flow through each aperture by compensating for any air flow variations with respect to incoming air flow into the bladder and achieving substantially uniform cooling arising from uniform air temperature and flow of air egressing through individual apertures.

2. An apparatus according to claim 1 , wherein the flow of cooling air to each heat source egressing through each bladder aperture is effected by the bladder having a nominal cross- sectional area in the locality of the plurality of apertures that is sufficient, as compared with the collective area of the apertures, to achieve substantially uniform air flow through apertures of substantially similar dimensions despite variations to the flow of air into the bladder.

3. An apparatus according to claim 2, wherein the nominal cross- sectional area of the inflated bladder is: two or more times the collective area of the apertures formed in the bladder, or approximately three times the collective area of the apertures formed in the bladder.23AMENDED SHEET (ARTICLE 19)

4. An apparatus according to any one of the preceding claims, wherein: inflation of the bladder, once fastened and inflated, causes the bladder to hover over the one or more PCB assemblies on which the heat sources are located, or the bladder is fastened to the one or more PCB assemblies in a configuration that causes the bladder to hover over the one or more PCB assemblies by using one or more fasteners that enable a distance to be maintained between the one or more PCB assemblies and the bladder once inflated.

5. An apparatus according to claim 4, wherein the one or more fasteners are rivets that each include a head portion disposed inside the bladder and a stem portion that extends through coaxial fastening apertures associated with the bladder and the one or more PCB assemblies.

6. An apparatus according to claim 5, wherein each of the one or more fasteners further includes a spacer disposed between the fastener head portion and the one or more PCB assemblies, and include a height that enables the bladder to hover a distance above the one or more PCB assemblies that substantially corresponds with the height of the spacer.

7. [Amended] An apparatus according to either claim 5 or claim 6, wherein the bladder apertures are formed during manufacture of the bladder, and the manufacture of the bladder further includes formation of fastening apertures through which rivets are configured to extend.

8. An apparatus according to claim 7, wherein the formation of the bladder apertures and fastening apertures is achieved using a datum method, wherein the fastening apertures which align with bladder fixation points on the one or more PCB assemblies are used as reference points to determine the location of each bladder aperture, thereby ensuring that each bladder aperture substantially aligns with the location of each source of heat on the one or more PCB assemblies once the bladder is inflated.

9. An apparatus according to claim 4, wherein the one or more PCB assemblies and the bladder include co-operating fastening means, including fastening apertures associated with24AMENDED SHEET (ARTICLE 19)the bladder configured to engage with hooks included in the one or more PCB assemblies during manufacture thereof.

10. An apparatus according to any one of the preceding claims, wherein the bladder includes one or more of: material having flexible properties; plastic material; or transparent material.

11. An apparatus according to any one of the preceding claims, wherein the one or more sources of forced air includes a blower, wherein: the blower is located inside the bladder and the bladder is sealed around an intake of the blower; or the blower is mounted externally to the bladder and the bladder is sealed around an outlet of the blower.

12. An apparatus according to claim 11 , wherein when the bladder includes a blower located inside the bladder, the bladder is formed from material including one or more open ends that are sealed to form sealed bladder ends, wherein one or more of the bladder ends includes at least one inlet aperture to accommodate incoming airflow from the blower and the inlet aperture is equal to or larger than a side profile dimension of the blower to enable the blower, once the seal between the bladder and blower intake is released, to be physically manipulated and removed through the inlet aperture.

13. An apparatus according to either claim 11 or claim 12, wherein the blower further includes one or more of: a fitted filter at the intake of the blower to substantially prevent debris from entering the bladder; or a gasket of open cell foam that seals the bladder and the intake of the blower when the blower is located inside the bladder.

14. An apparatus according to any one of the preceding claims wherein the bladder is configured such that the cross-sectional area of the bladder is substantially uniform along the length, and / or across the width, of the bladder.

15. An apparatus according to any one of claims 1 to 13 wherein the bladder is configured such that the cross sectional area of25AMENDED SHEET (ARTICLE 19)the bladder is substantially non-uniform along the length and / or the width of the bladder.

16. An apparatus according to any one of the preceding claims, wherein the cross-sectional dimension of the bladder when inflated is substantially: circular; square; rectangular; oval; or configured substantially as a concertinaed bellow.

17. An apparatus according to any one of the preceding claims, wherein the shape of each bladder aperture varies according to the particular type of air flow required for individual heat sources, wherein the shape of the bladder apertures includes any one or more of substantially: circular; square; rectangular; oval; or star shaped.

18. An apparatus according to any one of the preceding claims, wherein the size of each bladder aperture varies depending upon the particular air flow rate and / or air flow velocity required for individual heat sources.

19. One or more PCB assemblies including an apparatus for cooling one or more individual sources of heat disposed at locations on the one or more PCB assemblies, the apparatus configured in accordance with any one of the preceding claims.

20. A battery cell stack including one or more PCB assemblies configured in accordance with claim 19.

21. A battery storage system including a plurality of battery cell stacks each configured in accordance with claim 20.26AMENDED SHEET (ARTICLE 19)

Images