MODULAR ASSEMBLY FOR A STORAGE DEVICE OR BATTERY

Abstract

A modular assembly comprising several adjacent modules joined together by means for circulating a flow and which each contain at least one volume wherein there is a refrigerant fluid or coolant circulating in the said volumes under the action of circulation means and elements for storing and restoring a thermal energy.

Description

This invention relates to a modular assembly comprising a plurality of modules that are functionally interconnected by means for circulating a flow (electrical, fluid, etc.). An individual module is also concerned.

Such an assembly can more particularly define or contain a storage battery or a thermal energy storage and release unit supplied by a fluid, such as oil from an engine, in particular.

A thermal flow management problem arises both module by module and on such assemblies, when it is expected that they each contain at least one volume wherein is contained at least one of what follows:

• a refrigerant or heat transfer fluid that can circulate in said volumes under the action of circulation means,
• elements for storing and releasing a thermal energy,
• at least one element to be maintained at a certain temperature, and/or
• at least one heat-emitting element.

It is conceivable that an element to be maintained at a certain temperature and/or a heat-emitting element may consist of an electrolyte, an anode and/or a cathode of an electric power accumulator for a vehicle battery pack.

As for the refrigerant or heat transfer fluid as well as for thermal energy storage and release elements, they can in particular be contained in a storage and release unit as mentioned above, the latter as thermal regulation elements of the former.

Now, for example in the automotive or aeronautics field, the current trend to integrate in vehicles (cars, airplanes . . . ) systems that have to provide increased performance (turbo, super-capabilities, etc.) weighs down and tends to increase the capacity need for flow management systems. This is true, for electric flows in electric or hybrid vehicles and for fluid flows, for example in the air temperature conditioning units of these same vehicles, or in some exchangers.

In addition, the industry is prompted to accelerate the marketing of new technologies that can reduce pollution emissions, smooth any occasional increases in thermal loads or gradients in relation to a nominal sizing operation, or propose solutions to shift the release of available energy in time to another time, while fostering the operational functioning of an element in its optimum operating temperature range (such as a storage battery).

GB 2519742 proposes a modular assembly comprising several adjacent modules:

• that have a peripheral wall,
• which are interconnected by flow circulation means,
• and each containing at least one volume wherein there is at least one of the following:
  • a refrigerant or heat transfer fluid that can circulate in said volumes under the action of circulation means,
  • elements for storing and releasing thermal energy, at least a first layer comprising at least one thermal phase change material (PCM) being arranged at the periphery (of at least some) of said volumes.

In GB 2519742 these are devices for storing thermal energy for later use in space heating or water heating.

The problem is therefore different from that in the present application wherein the thermal management of the interior of the module volumes passes through the management of thermal exchanges between adjacent modules.

It is in this context that an assembly as aforesaid is hereby proposed, thus comprising several adjacent modules that have a peripheral wall through which the adjacent modules can be in thermal exchange, the said adjacent modules being interconnected by flow circulation means and each containing at least one volume wherein is present at least one of the following:

• • a refrigerant or heat transfer fluid that can circulate in said volumes under the action of circulation means,
  • elements for storing and releasing thermal energy,
  • at least one element to be maintained at a certain temperature,
  • at least one heat-emitting element, at least one first layer comprising at least one thermal phase change material (PCM) being arranged at the periphery of at least some of said volumes, including on one side:
  • where two modules are in contact by their respective peripheral walls, or
  • where said first layer is tight between two modules facing each other, and where at least a portion of at least one second layer comprising a thermally insulating material is also respectively interposed and tight.

The local complex MCP/thermal insulation makes it possible to associate thermal insulation between modules and a capacity:

• for lag effect on an undesired temperature variation (effect of PCM materials),
• and/or smoothing the temperature variations of the fluid and/or elements present in the internal volume of the module under consideration (via the PCM material).

It will thus be possible to avoid thermal disturbances between modules, while taking advantage of the thermal energy present in the volumes of these modules, the operating range of which may, if necessary, be managed (in the case of modules of a storage battery, in particular).

In GB 2519742 the lateral spacing between the modules and the thin air layers under the lids confirm that these effects are neither targeted nor attained. The intention is not to thermally benefit from a modular compactness.

For all purposes, it is specified that a phase change material—or MCP—refers to a material that is capable of changing its physical state within a restricted temperature range. Thermal storage can be achieved by using its Latent Heat (LH): the material can then store or transfer energy by simple change of state, while maintaining a substantially constant temperature and pressure, which of the state change.

And “tight” has the sense of being “in physical contact” with at least one of the two adjacent modules facing each other. There is no need for pressure, but for keeping in place and in contact for good thermal exchange. For example, between two successive modules 52, a set of three layers 15-23-15 is kept “tight” in FIG. 5, while, for example, in FIG. 6 there is kept “tight” together with each of these two modules 52 a set two layers 15-23 or 23-15, with a space 42 for circulating a thermal management fluid F established between the two respective layers 23.

In general, the thermally insulating material chosen, which will therefore not be a PCM material, will be an insulator such as glass wool, a porous insulator, a polyurethane or polyisocyanurate foam, or better still a porous thermally insulating material arranged in a vacuum chamber, to define at least one Vacuum Insulating Panel, VIP.

Indeed, with a VIP, the performance of the thermal management to be ensured will be further improved, or even the overall volume decreased with respect to another insulator.

It is therefore recommended that the thermally insulating material of the second layer comprise a porous thermal insulating material arranged in a vacuum chamber, to define at least one vacuum insulating panel, VIP.

“Porous” will mean a material that has interstices allowing the passage of air. Open cell porous materials therefore include foams but also fibrous materials (such as glass wool or rock wool). The passage interstices that may be described as pores have sizes of less than 1 or 2 mm so as to guarantee good thermal insulation, and preferably less than 1 micron, and preferentially still less than 10⁻⁹m (nanoporous structure), particularly for questions of ageing stability and therefore possible lower depression rate in the VIP envelope.

The term “VIP” is understood to mean a structure under a partial air vacuum structure (internal pressure that can be between 10 and 10⁴ Pa) containing at least one a priori porous thermal insulating material (pore sizes of less than 10 microns) It should be noted, however, that the expression “air vacuum” includes the case wherein this partial vacuum would be replaced with a “controlled atmosphere”: the insulating pouches would be filled with a gas that has a lower thermal conductivity than ambient air (26 mW/m·K)

Typically, the VIP panels (vacuum insulating panel, VIP) are thermal insulators wherein cores made of porous material, for example silica gel or silicic acid powder (SiO2), are pressed into a plate and each surrounded, partial air vacuum, a gas-tight wrapping foil, for example plastic and/or roll-formed aluminium. The resulting vacuum, with a residual pressure typically less than 1 hPa (1010² Pa), typically lowers the thermal conductivity to less than about 0.01/0.020 W/m•K under the conditions of use.

Now, in at least some applications or operating situations to be anticipated, it may be necessary to achieve a thermal insulation efficiency via said “second layer” in particular significantly higher than that of more conventional insulating materials, such as certain technical polymers like RYNITE® PET polyester resin or HYTREL® thermoplastic polyester elastomer from Dupont de Nemours®.

Typically, a thermal conductivity λ less than 0.008/0.01 W/m•K is preferably expected here.

With regard to these VIP panels and PCM materials, it was further noted that they do not seem to meet the expectations of the market so far. In particular, their implementation in the field is a problem, especially their conditioning.

Therefore, this choice of PCM/VIP active barrier is hereby deemed relevant.

In certain applications or operating situations to be anticipated, it may also be necessary to evacuate or bring thermal energy contained in the aforementioned volumes of the modules concerned, or to limit thermal transfer to objects to be thermally regulated (battery elements).

In such cases it is recommended that part of the periphery of at least some of the modules is devoid of at least the second layer where a module is in physical contact with a convective and/or conductive thermal energy transfer means.

It follows that at a localized area of a given module, heat transfer may pass through the PCM layer(s) or through the single non-insulating outer wall (typically made of polymer or metal) of the module peripherally limiting said volume at this location.

This may apply in particular if a given module defines an electric accumulator of a vehicle battery unit, wherein at least one electrolyte, an anode and a cathode arranged in said volume define all or part of said element to be maintained at a certain temperature and/or said heat-emitting element, the envelope being traversed by electrical connection means connected to the anode and cathode.

Indeed, we must be particularly vigilant to thermal control in order to prevent the cell from overheating.

In connection with this point, and to foster mass production, it is also proposed:

• that the first and second layers be grouped together in at least one pouch which will surround said volume,
• and that the thermally insulating material of the second layer comprise a porous material arranged in a vacuum chamber, to define at least one vacuum insulating panel, VIP.

The sheet or plastic film, or even metal or metal/plastic complex film of the pouch and/or the enclosure will foster the aforementioned thermal transfer desired, while ensuring an efficient manufacturing process. Indeed, since a VIP panel can typically be made with a heat-sealable metal layer film (for example aluminium) which is therefore a thermally good conductor, it will then be easy to use this layer for the said thermal transfer; same in the case of a metal wall that is a little thicker ( 1/10 mm for example) and therefore more rigid.

Definitely, it may even be favorable for the first and second layers to be distributed in two pouches that may be conformable or deformable and sealed together around said volume, thereby creating an envelope closing the volume.

Part of the welding periphery can then serve as a thermal transfer area.

In terms of implementing the aforementioned first and second layers, and in addition to the case in which the packaging of the VIP pouch will make the realization of the active ePCM/VIP barrier thus conditioned constitute itself the wall of the internal volume of the module concerned, two other embodiments are preferred, for the sake of energy efficiency, mass production capacity (typically automotive field), reliability and reduced costs, namely:

• a)—each module will have at least one peripheral wall which will close the volume, except possibly at the location of an opening leaving access to said volume,
• —and the first and/or second layers, which will be structurally distinct from said peripheral wall, will be arranged around this peripheral wall, with the second layer outside the first one, where there will exist a presence of the first and second layers,
• b) or each module will have at least one peripheral wall:
• a)—which will close the volume, except possibly at the location of an opening leaving access to said volume,
• and which will incorporate the mouldable material support and the first and second layers.

In conjunction with what has already been indicated, two applications (among others not excluded) have been particularly taken into account, because of the needs expressed by the market, as developed above.

These are:

• the case where the modules are or will contain electric accumulators of a battery pack for a vehicle, wherein at least one electrolyte, an anode and a cathode arranged in said volume will define all or part of the aforementioned element to be maintained at a certain temperature and/or said heat-emitting element;
• and the case in which:
  • the adjacent modules are those of a unit for storing and releasing thermal energy,
  • the volumes contain said thermal energy storage and release elements,
  • at least a first passage going through a wall of at least one of the modules allows said refrigerant or heat transfer fluid to enter and exit,
  • and second passages established between at least one of said modules allowing the refrigerant or heat transfer fluid to pass between the volumes.

These two cases are interesting in that they are based on a common solution, although concerning deeply different contexts:

• in a battery pack or a vehicle electrical accumulator, the electrical efficiency over time in fact depends significantly on the internal temperature conditions, in the pack, which must be contained in an optimum range of approximately 25 to 35° C.; otherwise the efficiency drops,
• in a unit for storing and releasing thermal energy, it is necessary to store this energy (typically after about 6-10 minutes) in the unit at a time, to conserve it for a certain time (typically several hours, for example 12 to 15 hours), then release it (typically less than 2/3 minutes, for example to an engine during a cold starting phase), all via a refrigerant or heat transfer fluid entering and/or exiting.

If necessary, the invention will be better understood and other characteristics, details and advantages thereof will become apparent upon reading the following description as a non-exhaustive example with reference to the appended drawings in which:

FIG. 1 is a block diagram of the storage-thermal exchanger type device, in exploded view;

FIG. 2 shows a vertical section of two modules of the unit in FIG. 1 superimposed, with an integrated active barrier 15/23;

FIGS. 3 to 7 show in vertical section embodiments of battery cells arranged in a lateral line;

FIG. 8 outlines in vertical section two pouches ready to be inter-assembled (see arrows) to constitute a pouch-type cell or battery module;

FIGS. 9,10 outline in vertical section two results of the assembly of FIG. 8;

FIG. 11 shows in vertical section an alternative of FIG. 10, with PCM only inside (INT) in a closed state of a hingeable panel with continuous insulation;

FIGS. 12,15 show in vertical section, closed on themselves, two strips with PCM/VIP structure (the PCM layer was not shown, it doubles the inner porous layer 23), and

FIGS. 13,14 outlines, in local vertical section (extensible on both sides in the case of a hingeable panel) two possible structures of insulating pouches (19 below),

FIG. 16 is a diagram in vertical section of an alternative solution of FIG. 2,

and FIGS. 17, 18 are top diagrams (horizontal section on the left) and with cutaway embodiments that can be those of FIGS. 3 to 6.

As mentioned above, the invention proposes a modular embodiment that can be adjusted in terms of volume or mass, and whose thermal efficiency provided by the local association PCM/thermal insulation will achieve both a thermal insulation between modules that (via the PCM material) a smoothing ability of the temperature variations of elements present in the internal volume of the module concerned (case of a battery application) and/or an ability to delay a temperature variation of a fluid that is present in the volume (case of a storage application/exchanger) or the object to be thermally regulated (case of a battery).

Thus, it can be seen in the appended figures and non-exhaustively, three modular assemblies 1, 10, 100 respectively: storage/exchanger FIGS. 1, 2 and two solutions of storage batteries, respectively FIGS. 3-10 and 11, 12, respectively.

Each comprises several modules 3 each having an interior volume 7 limited externally by a peripheral wall 5.

Note, however, that if a modular assembly is recommended, here it is the individual thermal structuring of each “module” that takes precedence. Each module is therefore to be considered as such, as a thermally independent whole.

The modules 3 are functionally interconnected by means 6 for circulating a flow 9:

• the flow of a refrigerant or heat transfer fluid that can circulate in an external circuit 110 and in said volumes under the action of circulation means 11,
• and/or electrical energy flow when the means 6 (such as cables) then provide an electrical connection, typically serial or parallel, between the modular elements 3 (each forming or enclosing an electric accumulator) of the battery pack, in order to obtain an electric voltage for a vehicle. Only FIGS. 3-4 outline these electrical connections, to avoid overloading the other FIGS. 5-11 concerned,
• and/or still fluid, by an exchange means 44; see below in the “battery” application (FIGS. 3-12); This exchange means 44 will then act as a means for circulating a flow between the modules.

FIGS. 3,4,10 (the other FIGS. 5-9,11 not listed in order to streamline details), diagrammatically shows at least one electrolyte 16, and an anode 14 and a cathode 17 arranged in the volume 7 of each of the electric accumulators 3, this defining one or more elements to be maintained at a certain temperature and/or giving off heat, when in operation all or part of the anode, cathode and the electrolyte 16 will be heated within these accumulators. In these figures, the polarized terminals of these anode and cathode which connect to the means 6 locally through the wall 5 are also distinguished at 140,170.

In the example in FIG. 1, the adjacent two-by-two modules 3 of the assembly 1 are those of a unit for storing and (subsequently) releasing thermal energy. The volumes 7 each contain elements 13 for storing and (subsequently) releasing this thermal energy transported by the flow 9 of the circulating fluid, which, refrigerant or heat transfer fluid, is a priori liquid (water, oil in particular), but could to be gaseous, like air to be conditioned.

Some first passages 33,35 go through, at opposite ends of the unit 1, covers 32 covering, by closing if necessary, the two end modules of what is here formed in a stack, to let in and out the fluid that will flow between the modules. This circulation can be serial or parallel.

Externally, the cover 32 opening side 31 (see below) can be doubled by a single pouch 34 with VIP constitution. And a mechanical protection plate 36 can close it all, along the axis 27, as illustrated. A mechanical protection sleeve or sheath 38 open at both ends, for example hard plastic, further envelopes the modules 3 and parts 32,34,36.

To allow the flow of fluid 9 to pass between the volumes, some second passages 30 are established between all the modules in pairs, in walls 29 transverse to the stack. Each wall 29 defines in this case the bottom of the module concerned, in addition to the peripheral wall 5.

In contrast to their bottom 29, the modules are open, at 31, to allow the placing in each volume 7 thus defined elements 13 for storing and releasing the thermal energy that will have been provided by the fluid 9. The elements 13 will favorably be balls made partially of material (for example in addition to a polymer) or totally of PCM, for thermal efficiency and ease to be arranged in their number in host volume.

As constitution of the elements 13 (or material 15 below) provision may be made for example for rubber composition as described in EP2690137 or in EP2690141, namely in the second case a crosslinked composition based on at least one vulcanized “STR” silicone elastomer at room temperature and comprising at least one phase change material (PCM), said at least one silicone elastomer that has a viscosity measured at 23° C. according to ISO 3219 which is less than or equal to 5000 mPa·s.

In this composition, the elastomer matrix may be predominantly constituted (i.e. based on an amount greater than 50 phr, preferably greater than 75 phr) of one or more “STR” silicone elastomers. Thus, this composition may have its elastomer matrix comprising one or more silicone elastomers in a total amount greater than 50 phr and optionally one or more other elastomers (i.e. other than “STR” silicones) based on a total quantity of less than 50 phr. The thermal phase change material (PCM) consists of n-hexadecane, eicosane or a lithium salt. Alternatively, the PCM material could be based on fatty acid, paraffin, or eutectic or hydrated salt.

In fact, the choice of this material and its packaging, in particular its dispersion within a polymer matrix, will depend on the intended application and the expected results.

Fastening means 40, which may be tie rods, mechanically secure the modules together, in this case a stacking axis 27.

To protect from external (EXT) heat or cold at least a first layer 15 comprising at least one PCM material is arranged around each volume 7, including on one side where two adjacent modules face each other and where at least a portion at least one second layer 23 comprising a thermally insulating material is also interposed, as shown diagrammatically in the figures “in situation” 2-6 and 9.

To best enhance this “active” insulation as soon as a PCM material is included therein, the thermally insulating material of the second layer 23 comprises, in the preferred versions illustrated, a porous heat-insulating material placed in a vacuum chamber 37, to define at least one vacuum insulating panel, VIP.

A priori the second layer 23 will be, where the two layers PCM/VIP exist, arranged around the first layer 15, so between it and the exterior (EXT); it being specified, however, that the second layer 23 could be interposed between two PCM layers 15a, 15b. In that case:

• a) if the exterior (EXT) is the neighbouring cell 52, the two PCM layers 15a, 15b may be the same,
• b) if the exterior (EXT) is the environment around a complete battery pack, beyond the lateral periphery and its wall 55, as for example in zones 111, FIG. 4, then the change of phase temperatures will be different, the change of state temperature increasing as one goes inward (INT).

Note that each “layer” 15a, 15b may be formed of several adjoining sub-layers of lesser thickness each with its change of state temperature in case b), for a gradual evolution of these temperatures.

Thus, it can be arranged such that an excessively cold or hot external temperature might interfere only slightly with that in the volume(s) 7, the first layer 15 (or the internal one 15a) being, in the Battery application, defined to smooth out internal temperature variations in this(these) volume(s) and within the fluid in the periphery and to delay the propagation towards the heat or excessively cold modules (typically less than 25° C. or more than 35° C.).

In order to optimize this approach, it is recommended that the active thermal barrier formed by the PCM/thermal insulation layers thus comprise at least one VIP panel formed by a pouch 19 wherein the second layer 23 will be initially integrated. In order to constitute the/each panel VIP 19, then, there should be found a porous thermal insulating material, which can therefore be the second layer 23, this material being contained in the casing 37 forming a sealed enclosure to said material and air. Once an air gap is established in the envelope, the pouch nevertheless slightly conformable or deformable forming the VIP panel will be constituted.

As regards the porous thermal insulating material thus contained in the envelope 37, it should be noted that it will advantageously be made of a porous material (for example with a nanostructure, such as silica powder or airgel, such as a silica airgel) confined in a sheet or a flexible film 49 or 51 that will not let through the water vapour or gas. The VIP obtained will be emptied of its air to obtain for example a pressure of a few millibars, and can then be sealed. Typically, the thermal conductivity A of such a VIP will be 0.004/0.008 W/m·K. The use of vacuum insulating panels should achieve a thermal resistance R=5 m²·K /W with only 35 mm of insulation. Examples, applicable here, of VIP panel and super-insulating material are provided in PCT/FR2014/050267 and WO2014060906 (porous material), respectively. A possible composition of the material 23 is as follows: 80-85% silica dioxide (SiO2), 15-20% silicon carbide (SiC) and possibly 5% other products (binder/fillers). A thickness of 0.4 to 3 cm is possible.

At this stage of the presentation of the invention, it has been understood that an important element thereof relates to the modular design of a thermal management structure with the purpose of controlling the temperature in an internal volume that this structure surrounds, either structurally dissociated, as an isothermal bag surrounds a content, or structurally integrated: the materials of the thermal barrier 15,23 thus constitute an integral part of the structure. What must be understood as well is the desire to make the thermal management of each module or each internal volume autonomous. Indeed, it turned out that this:

• must be able to respond more precisely to the needs of the customers, notably by making it possible to reduce the number of modules for the same objective, with resulting weight and space savings;
• authorizes assemblies wherein the “adjacent” modules will not necessarily be strictly contiguous although very close (less than ¾ cm apart), as for example in FIG. 4 or 6 where there is a space 42 between two integrated thermal barrier modules 15,23 (FIG. 4) or external thermal barrier modules 15,23, inserted (FIG. 6). Indeed, the fact of having provided a modular structure, with this barrier here PCM/VIP between two such modules 3 or adjacent volumes 7, in the retained lateral alignment, allows in at least one direction (here along a lateral face) to reserve this space 42 to circulate in a natural or forced way a fluid F which could advantageously facilitate a thermal transfer if, as recommended in the case of a “battery application” as FIGS. 4 and 6, a face other that the side faces of the wall 5, here the bottom 29, is not only devoid of said layers 15/23 of the thermal barrier but doubled (here below) by a means 44 of convection exchange (arrows H in different figures), natural or forced, such as a thermally conductive plate, for example metal, or at least one conduit in which an exchange fluid, such as water, would circulate to evacuate the heat provided by the layer or layers 15 made of PCM coming into contact with it, as illustrated;
• helps to rationalize, at low cost, mass production, in several applications, since by providing the thermal barrier 15,23 between two modules, we can:
  • use a single strip 50 of VIP pouches in the context of the integrated thermal barrier embodiment detailed hereinafter which can make it possible to produce sidewall and bottom modules 29 thus provided, as FIGS. 2,3,
  • dispense with at least one pouch 34 with VIP constitution at the end of stack FIG. 1;
• easily use the strips 50 mentioned above, these strips, such as those of FIGS. 12,15, that can be placed laterally (axis 51) around the body of a battery cell 52, as can be imagined, each closed on themselves, seeing FIGS. 4,6,7, to each double their side wall 5 with the thermal barrier 15,23 that each band will then integrate;
• possibly design independent multi-function modules, such as the pouch-type cells 100 (battery pouch Cell) of FIGS. 10,11.

Thus, as outlined in FIG. 6, a space 42 between two thicknesses of said second layer 23 interposed between two adjacent modules 52 may make it possible to circulate, in a natural or forced manner, a fluid F in order to evacuate calories (even frigories) present in these spaces because of exchanges between modules. Each space 42 can therefore be connected to the respective conduits for supplying the fluid 43a and for discharging the fluid 43b.

From the foregoing, it shows that the thermal insulation portion formed by the barrier 15/23, preferably with a VIP constitution, can be structurally dissociated from both volumes 7 and the peripheral wall 5 of each module (in the case of the cells 52 mentioned above). In the latter case this part 15/23 will surround the wall. FIGS. 4,6,7, outlines an independent PCM/VIP barrier resulting from a band 50 articulated in several places because the flexible sheets or films 49 (or parts of the same sheet or single film) which form the envelope 37 are:

• either in direct contact in the intermediate zones between two successive heat-insulating pouches 19 each with PCM 15/porous material layers 23 integrated within the global vacuum space created, as in FIG. 12 or 15;
• or filled over a few mm thick of a deformable structure 79 may be formed by a conformable or deformable support in a polymer mesh of a few mm thick impregnated with an airgel 81, for example silica, or its pyrolate (pyrolyzed airgel, it being specified that this pyrolate alternative applies to each case of the present description in which a thermally insulating porous material is concerned), like FIG. 12.

FIGS. 8,13,14 we see, among others, different ways of making a band 50, see individually a pouch 19 with 15/23 material and VIP constitution of which it is favorably made.

In the two preferred embodiments proposed, each pouch 19 comprises at least one closed outer envelope 37 which contains the first and second elements 15/23 and consists of at least one conformable or deformable sheet 49 sealed to the PCM material, with:

• a) either said sheet 49 which is sealable (thermally/chemically, such as at 49a, 49b, around the bag) and impervious to the porous material 23 and to the air (or even to water), such that an air gap prevailing in the envelope 37, a so-called vacuum insulating panel (VIP) is thus defined, as shown in FIGS. 7,13;
• b) the second heat-insulating element 23 contained inside a second closed sealable flexible envelope 53 (as above) and sealed to the porous material and to the air, such that an air space prevailing in the second envelope, a said vacuum insulating panel (VIP) is thus defined, as shown in FIGS. 8,14.

It should be noted that two layers 15 (15a, 15b) containing one or more PCM materials could (as in FIG. 7) be arranged on either side of the layer of porous material 23.

Sheet(s) or film(s) 49 and 53 can typically be made in the form of a multilayer film comprising polymer films (PE and PET) and aluminium in the form of, for example, laminated (foil of about ten micrometres thick) or metallized (vacuum coating of a film of a few tens of nanometres). The metallisation can be carried out on one or both sides of a PE film and several metallised PE films can be complex to form a single film. Sample film design:

• PE internal sealing, approx. 40 μm—vacuum metallisation Al, approx. 0.04 μm—PET outer layer, approximately 60 μm.

As already noted, comparing FIGS. 2 and 3-7, it should be noted that the modules 3, if formed each time, on a complete modular assembly, in a stack or line, are superimposed by their openings 31 and bottom 29, FIG. 2, while they are laterally in line, side by side through part of their peripheral wall FIGS. 3-7.

In the application “superimposed modules” for the storage-exchanger 1 (see FIG. 2) is therefore not only the peripheral wall 5 but also the bottom 29 which are provided with the double barrier 15/23, for example with minus one strip 50, folded in the corners, used for three sides (see FIG. 2 in section where the diagram, rough, does not show the strip), two single pouches 19 for the 4th and 5th sides, the last side being open (opening 31). Conversely, FIGS. 3-4, the band 50 may be arranged horizontally at the single side wall 5. And all these structures, here with VIP constitution, will be favorably embedded with a support 55. This support will favorably be one-piece. It may be plastic, metal (stainless steel, aluminium) or composite, in particular. Molded manufacturing will be preferred.

The reference to a peripheral side wall 5 of mouldable material covers both fibre-filled and injected thermoplastic resins and thermosetting resins impregnating a mat, such as a woven or a nonwoven.

FIG. 3, the bottom 29 also incorporates a PCM/VIP 15/23 gate. It may be at least one pouch 19 or two flat pouches, side by side between which the passage channel(s) for electrical connections terminals 140,170 would pass. In this figure, it has been assumed that an electric cell 52 (completely closed and thus containing the elements 15, 16, 17) has been placed, in each central space 56 delimited by the inner face of the walls 5 and 29, by the opening 31 opposite the transverse bottom 29. FIG. 4 is instead diagrammatically the case in which the hollow interior defined by the inner face of the walls 5 and 29 is directly the volume 7. In this case, the elements 15,16,17 placed there are held by a cover 57 which closes the opening 31. The situations can be interchanged between the two figures.

FIG. 5, and in more detail FIG. 7, a special feature lies in the VIP wall 23 which is common to the two adjacent cells 52. Thus, between two adjacent cells 52, there is at least one vacuum bag with three layers: a porous insulating layer 23 between two layers PCM, a priori identical. The thickness of the layer 23 may be twice that of the dedicated layer versions of the other variants. As FIGS. 5, 6, a mechanically protective sleeve 38 may surround the batch of cells and their individual thermal barriers 15/23.

FIGS. 8-11 diagrammatically show another way of making a battery cell, in this case a “pouch” cell FIGS. 10-11, while it may be prismatic cells FIG. 9 in the previous figures.

FIG. 8, two elongated pouches 19 each formed of a casing 37 are outlined, face to face. Each has two ends 49a, 49b of outer films 49 welded together. It is these two pairs of ends 49a, 49b that we will be able to join together and solder by couple, as shown in FIGS. 9-11 to constitute a closed central space corresponding to (FIG. 9) to the space 56 already present in the solution of FIG. 3 is directly to the internal volume 7 (FIGS. 10-11), since the wall 49 will then be chosen to resist the electrolyte and exchanges related to the electrical production in the volume, being so necessary to double this by an ad-hoc wall. FIGS. 10,11, note the bent outward appearance (EXT) of sealed envelopes 37/51 flexible sheets, being specified that such a shape can result from a shortening, on each envelope, the length L1 of the inner sheet relative to the length L2 of the outer sheet, this creating a mechanical tension at the location of the end seals which hinge the envelope.

In the embodiment of FIGS. 12, 15, bends can therefore be made at the location of the hinge zones 21, where two sheets 49 are in direct contact with one another and which are each interposed between a pouch 19 and a thermally insulating intermediate zone 59 containing at least one porous material 23.

At least one PCM layer may be interposed between the bottom 29 and the convective exchange means 44, the bottom 29 being able to integrate this or these layers.

FIG. 16 shows an alternative to the solution of FIG. 2: the bottoms 29 may not comprise layers 15 or 23. The same material as that of the wall 5 may be used, for a one-piece constitution.

Regarding FIG. 17, it shows in plan view a case in which the means 44 for transferring thermal energy acts in particular by conduction, via conduits 48 for the circulation of a fluid which, via the thermal energy transfer plate 50 (typically metal) which doubles a face 58 of the combined blocks 3 (here several adjacent cells 52), ensures the evacuation of the thermal energy supplied to this plate by the PCM layers 15.

It should be noted that such a layer PCM 15 laterally surrounds (on the four lateral faces other than the face 58 and its opposite, see figure) all the blocks 3/52 joined together with itself doubled externally by a thermal insulator 23.

FIG. 18 outlines an alternative where the thermal energy transfer means 44, here by convection, extends all around a PCM 15 which surrounds laterally (on the four lateral faces other than the lower and upper faces here; see figure) all the blocks 3/52 together.

The means 44 for convection transfer may be an outer plate carrying fins 46.

We equally figured in 38FIG. 17 shows the sleeve, or more generally the envelope in one or more parts, which serves as a mechanically protective wall, or even a lateral holding means (see solution in FIG. 1) to the elements they surround; units 3, layers 15/23 . . . In the solution of FIG. 18, the outer peripheral plate carrying fins 46 can play this role, especially if the plates are joined together to form a continuous wall.

In all the above solutions, it has been noted that it is through their peripheral walls 5 that the adjacent modules 3 would exchange more calories or frigories if the layers 15/23 and/or the VIP envelopes were not present, thus altering their internal management.

Claims

1. A modular assembly comprising several adjacent modules that each have a peripheral wall, said adjacent modules being interconnected by flow circulation means and each containing at least one volume wherein is present at least one of the following: a refrigerant or heat transfer fluid that can circulate in said volumes under the action of circulation means,elements for storing and releasing thermal energy,at least one element to be maintained at a certain temperature,at least one heat-emitting element, at least a first layer comprising at least one thermal phase change material (PCM) being arranged at the periphery of at least some of said volumes, including on one side:where the peripheral walls of two adjacent modules are in contact such that the two modules exchange thermally with each other, orwhere said first layer is tight between two adjacent modules facing each other, such that said two modules thermally exchange with each other, orwhere a space is reserved between two modules for circulating a fluid in a natural or forced manner, the space being connected to respective conduits for supplying the fluid and for discharging the fluid,and where at least a portion of at least one second layer comprising a thermally insulating material is interposed.

2. The modular assembly according to claim 1, wherein the thermally insulating material of the second layer comprises a porous thermal insulating material arranged in a vacuum chamber, to define at least one vacuum insulating panel.

3. The modular assembly according to claim 1, wherein part of the periphery of at least some of the modules is devoid of said first and/or second layers, where a module is in physical contact with a means for thermal energy transfer by convection and/or conduction.

4. Modular assembly comprising several adjacent modules each having a peripheral wall: through which the adjacent modules can be in thermal exchange with each other, said adjacent modules being joined together by flow circulation means,and which closes a volume, except possibly at the place of an opening allowing access to said volume, in which at least one of the following is present: a refrigerant fluid or coolant that can circulate in said volumes under the action of circulation means,elements for storing and releasing thermal energy,at least one element to be maintained at a certain temperature,at least one heat-emitting element,at least a first layer comprising at least one thermal phase change material (PCM) being arranged at the periphery of at least some of said volumes, including on one side:where said first layer is tight between two modules facing each other,and where at least a portion of at least one second layer comprising a thermally insulating material is interposed,the first and/or second layers, which are structurally distinct from said peripheral wall, being arranged around the peripheral wall, with the second layer outside the first one, where there exists a presence of the first and second layers.

5. Modular assembly comprising several adjacent modules each having a peripheral wall: through which the adjacent modules can be in thermal exchange with each other, said adjacent modules being joined together by flow circulation means,and which closes a volume, except possibly at the place of an opening allowing access to said volume, in which at least one of the following is present: a refrigerant fluid or coolant that can circulate in said volumes under the action of circulation means,elements for storing and releasing thermal energy,at least one element to be maintained at a certain temperature,at least one heat-emitting element,at least one first layer comprising at least one thermal phase change material (MCP) being disposed on the periphery of at least some of said volumes, including on one side where the peripheral walls of two adjacent modules are in contact, so that the two modules exchange thermally with each other, and where at least a portion of at least a second layer comprising a thermally insulating material is interposed, the peripheral walls each incorporating a support of mouldable material and the first and second layers.

6. The modular assembly according to claim 1, wherein the modules define or enclose electrical accumulators of a battery pack for a vehicle, where at least one electrolyte, and an anode and a cathode disposed in each of said volume, define all or part of said element to be maintained at a certain temperature and/or said heat-emitting element.

7. The modular assembly according to claim 1, wherein a space is reserved between two thicknesses of said second layer interposed between two adjacent modules for circulating a fluid naturally or forcefully.

8. The modular assembly according to claim 1, in which: the modules are those of a unit for storing and releasing thermal energy,the volumes contain said storage and release elements of said thermal energy,at least a first passage going through a wall of at least one of the modules allows said refrigerant or heat transfer fluid to enter and exit,and second passages established between at least one of said modules allowing the refrigerant or heat transfer fluid to pass between the volumes.

9. The modular assembly according to claim 1, wherein the modules as a whole are surrounded by a said first layer comprising at least one doubled thermal phase change material (MCP): by a said second layer comprising a thermally insulating material, except at the location of a plate for transferring thermal energy supplied to this plate by said first layers,or by externally-carrying plates of fins acting as means for transferring thermal energy supplied to these plates by said first layers.

10. Module for a modular assembly according to claim 1, wherein the first and second layers are grouped in at least one pouch surrounding said volume, and the thermally insulating material of the second layer comprises a porous material arranged in a vacuum chamber, for defining at least one vacuum insulating panel, the first and second layers being distributed in two pockets sealed together around said volume, thus creating an envelope closing the volume, the module defining a electric accumulator of a vehicle battery pack, where at least one electrolyte, an anode and a cathode arranged in said volume define all or part of said element to be maintained at a certain temperature and/or said heat-emitting element, the envelope being traversed by electrical connection means connected to the anode and cathode.

11. The module according to claim 10, wherein the electric accumulator is a battery pouch Cell.

12. (canceled)

13. (canceled)