Battery module with thermal management system

Abstract

A battery pack, which may for example be used for powering electric vehicles and other types of electric equipment, includes an enclosure with interconnected walls, battery cells contained within the enclosure, a battery management system operatively connected to the battery cells and located within the enclosure, and a heat-conducting plate defining one or more of the interconnected walls of the enclosure. The heat-conducting plate includes a first section, with the battery cells and the battery management system in heat exchange relationship with the first section, and a second section in heat exchange relationship with the first section. The second section of the heat-conducting plate is in heat exchange relationship with an environment outside the enclosure, for providing heat exchange between the environment and the battery cells and the battery management system.

Description

BATTERY MODULE WITH THERMAL MANAGEMENT SYSTEMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority on United States Patent Application No. 63 / 581 ,810 filed September 11 , 2023, the entire content of which is incorporated herein by reference.TECHNICAL FIELD

[0002] This disclosure generally relates to electric batteries and, more particularly, to thermal management systems to remove heat from such batteries or provide heat to such batteries.BACKGROUND

[0003] Electric vehicles and othertypes of electric equipment may be powered by one or more electric batteries. Each battery typically includes a plurality of cells that are operatively connected to one another. The batteries generate heat when power is drawn from them and when power is provided to them (e.g., during charging). In some cases, operating batteries when a temperature of the batteries exceeds a maximum temperature threshold may impede their performance and, in some cases, may damage the batteries. Hot ambient temperatures may also contribute to elevated battery temperatures. Additionally, performance of the batteries may decrease when they are operated at a temperate below a minimum temperature threshold. While attempts to better regulate the temperature of batteries have been made, improvements are nonetheless sought.SUMMARY

[0004] There is accordingly provided, in accordance with one aspect, a battery pack, comprising: an enclosure including interconnected walls; battery cells contained within the enclosure; a battery management system operatively connected to the battery cells and located within the enclosure; and a heat-conducting plate defining one or more of the interconnected walls of the enclosure, the heat-conducting plate having: a first section, the battery cells and the battery management system in heat exchange relationship with the first section; and a second section in heat exchange relationship with the first section, the second section in heat exchange relationship with an environment outside the enclosure for providing heat exchange between the environment and the battery cells and the battery management system.

[0005] In certain embodiments, the battery pack as defined above and described herein also includes one or more of the following features, in whole or in part, and in any combination.

[0006] In an embodiment, the battery management system has a printed circuit board having a board wall and electronic components secured to the board wall, the board wall having a first face and a second face opposite the first face, the electronic components mounted on the first face, the second face oriented towards the heat-conducting plate.

[0007] In an embodiment, a majority of the weight of the battery cells is supported by the first section of the heat-conducting plate.

[0008] In an embodiment, the first section includes a first plate and the second section includes a second plate, the first plate and the second plate lying in respective planes that intersect one other to define an angle between the first plate and the second plate, and the heat- conducting plate including heat pipes mounted to the first plate and / or the second plate.

[0009] In an embodiment, the heat pipes are mounted to both the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

[0010] In an embodiment, the first plate and the second plate are monolithically formed from a single heat-conducting plate that is folded to define the angle between the first plate and the second plate.

[0011] In an embodiment, the first section includes a first plate and the second section includes a second plate, the heat-conducting plate including heat pipes mounted to the first plate and / or the second plate.

[0012] In an embodiment, the heat pipes are mounted to both the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

[0013] In an embodiment, a heat sink mounted to the second plate, the heat sink being in heat exchange relationship with the second section of the heat-conducting plate.

[0014] In an embodiment, a fan mounted to the heat sink, the fan operable to induce a cooling air flow through the heat sink.

[0015] In an embodiment, the heat pipes are received within grooves defined by the first plate and by the second plate.

[0016] In an embodiment, the heat pipes are flattened.

[0017] In an embodiment, top surfaces of the heat pipes are substantially flush with a surface of the heat-conducting plate surround the grooves.

[0018] In an embodiment, the top surfaces of the heat pipes are in direct contact with the battery cells.

[0019] There is also provided, in accordance with another aspect, a battery pack, comprising: an enclosure including interconnected walls, the enclosure having a vent defined through one of the interconnected walls and providing fluid communication between an internal volume of the enclosure and an environment outside the enclosure; battery cells contained within the enclosure; a heat-conducting plate defining one or more of the interconnected walls of the enclosure, the heat-conducting plate having a first section and a second section, the battery cells in heat exchange relationship with the first section and the second section being in heat exchange relationship with the first section, the second section being in heat exchange relationship with an environment outside the enclosure for providing heat exchange between the environment and the battery cells; and a valve in fluid communication with the vent of the enclosure, the valve having a closed configuration in which the internal volume is fluidly disconnected from the environment by the valve and an open configuration in which the internal volume is in fluid communication with the environment through the valve.

[0020] In certain embodiments, the battery pack as defined above and described herein also includes one or more of the following features, in whole or in part, and in any combination.

[0021]

[0022] In an embodiment, the valve is a pressure relief valve, the valve moving from the closed configuration to the open configuration in response to a pressure difference between a pressure inside the volume and a pressure of the environment exceeding a pressure threshold.

[0023] In an embodiment, the vent is defined through the second section of the heat- conducting plate, the second section of the heat-conducting plate being disposed at an angle relative to the first section of the heat conducting-plate.

[0024] In an embodiment, a heat sink mounted to the second section, the heat sink in heat exchange relationship with the second section of the heat-conducting plate, and wherein the vent extends through the heat sink.

[0025] In an embodiment, a cover overlapping the battery cells, the battery cells disposed between the cover and the first section of the heat-conducting plate, the cover being made of a polymeric material that is configured to locally sublime when exposed to a temperature above a temperature threshold.

[0026] In an embodiment, the first section includes a first plate and the second section includes a second plate, the heat-conducting plate including heat pipes mounted to both of the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

[0027] There is further provided, in accordance with another aspect, an assembly of battery packs, comprising: an outer casing defining a battery-receiving volume; and multiple battery packs contained within the battery-receiving volume, each of the battery packs having: an enclosure including interconnected walls; battery cells contained within the enclosure; and a heat- conducting plate defining one or more of the interconnected walls of the enclosure, the heat- conducting plate having: a first section supporting the battery cells, the battery cells being in heat exchange relationship with the first section; and a second section in heat exchange relationship with the first section; wherein the outer casing defines openings providing fluid communication between the battery-receiving volume and an environment outside the outer casing, the second sections of the battery packs each facing a respective one of the openings.

[0028] There is alternately provided a battery pack, comprising: an enclosure including interconnected walls; battery cells contained within the enclosure; a battery management system operatively connected to the battery cells and located within the enclosure; and a heat-conducting plate defining one or more of the interconnected walls, the heat-conducting plate having a first section, the battery cells and the battery management system in heat exchange relationship with the first section, and a second section in heat exchange relationship with the first section, the second section in heat exchange relationship with an environment outside the enclosure for providing heat exchange between the environment and the battery cells and the battery management system.

[0029] The battery pack as defined above and described herein may also include one or more of the following features, in whole or in part, and in any combination.

[0030] In certain aspects, the battery management system has a printed circuit board having a board wall and electronic components secured to the board wall, the board wall having a first face and a second face opposite the first face, the electronic components mounted on the first face, the second face oriented towards the first section of the heat-conducting plate.

[0031] In certain aspects, the electronic components include balancing resistances and metal oxide silicon field effect transistors mounted on the board wall.

[0032] In certain aspects, the battery cells are supported by the first section.

[0033] In certain aspects, the first section includes a first plate and the second section includes a second plate, the heat-conducting plate including heat pipes mounted to both of the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

[0034] In certain aspects, a heat sink mounted to the second plate, the heat sink in heat exchange relationship with the second section of the heat-conducting plate, the heat sink and the second plate being two parts of a single monolithic body.

[0035] In certain aspects, a fan mounted to the heat sink, the fan operable to induce a cooling air flow through the heat sink.

[0036] In certain aspects, the heat sink includes fins protruding from the second plate away from the battery cells.

[0037] In certain aspects, the heat pipes are received within grooves defined by the first plate and by the second plate.

[0038] In certain aspects, the heat pipes are flattened.

[0039] In certain aspects, a volume of the enclosure is free of the heat pipes.

[0040] There is alternately provided an assembly, comprising: an outer casing defining a battery-receiving volume; and battery packs contained within the battery-receiving volume and having: an enclosure including interconnected walls; battery cells contained within the enclosure;and a heat-conducting plate defining one or more of the interconnected walls, the heat-conducting plate having a first section supporting the battery cells, the battery cells in heat exchange relationship with the first section, and a second section in heat exchange relationship with the first section, wherein the outer casing defines openings providing fluid communication between the battery-receiving volume and an environment outside the outer casing, the second sections of the battery packs each facing a respective one of the openings.

[0041] The assembly as defined above and described herein may also include one or more of the following features, in whole or in part, and in any combination.

[0042] In certain aspects, the outer casing includes a base, each of the battery packs mounted on the base.

[0043] In certain aspects, the battery packs are distributed along at least two rows and at least two columns.

[0044] In certain aspects, fans are mounted to the outer casing and each in register with a respective one of the openings, the fans configured to induce a cooling airflow within the batteryreceiving volume.

[0045] In certain aspects, the battery packs include heat sinks at the second sections, the heat sinks each facing a respective one of the openings.

[0046] There is alternately provided a battery pack, comprising: an enclosure including interconnected walls, the enclosure having a vent defined through one of the interconnected walls and providing fluid communication between an internal volume of the enclosure and an environment outside the enclosure; battery cells contained within the enclosure; a heat- conducting plate defining one or more of the interconnected walls, the heat-conducting plate having a first section, the battery cells in heat exchange relationship with the first section, and a second section in heat exchange relationship with the first section, the second section in heat exchange relationship with an environment outside the enclosure for providing heat exchange between the environment and the battery cells; and a valve in fluid communication with the vent of the enclosure, the valve having a closed configuration in which the internal volume is fluidly disconnected from the environment by the valve and an open configuration in which the internal volume is in fluid communication with the environment through the valve.

[0047] The battery pack as defined above and described herein may also include one or more of the following features, in whole or in part, and in any combination.

[0048] In certain aspects, the valve is a pressure relief valve, the valve moving from the closed configuration to the open configuration upon a pressure difference between a pressure inside the volume and a pressure of the environment exceeding a pressure threshold.

[0049] In certain aspects, the vent is defined through the second section of the heat- conducting plate.

[0050] In certain aspects, a heat sink mounted to the second section, the heat sink in heat exchange relationship with the second section of the heat-conducting plate.

[0051] In certain aspects, the vent is defined through the heat sink.

[0052] In certain aspects, a fan is mounted to the heat sink, the fan operable to induce a cooling air flow through the heat sink, the fan aligned with the vent.

[0053] In certain aspects, a cover overlapping the battery cells, the battery cells disposed between the cover and the first section of the heat-conducting plate, the cover configured to locally sublime when exposed to a temperature above a temperature threshold.

[0054] In certain aspects, the cover is made of a polymeric material.

[0055] In certain aspects, the first section includes a first plate and the second section includes a second plate, the heat-conducting plate including heat pipes mounted to both of the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

[0056] There is alternately provided a battery module, comprising: battery packs, a battery pack of the battery packs having: an enclosure including interconnected walls; battery cells contained within the enclosure; and a battery management system operatively connected to the battery cells and located within the enclosure; and a master battery management system operatively connected to the battery packs and having: a first printed circuit board including a microprocessor connected thereto; a second printed circuit board including a converter connected thereto; and a post, the first printed circuit board secured to the second printed circuit board viathe post, the post electrically connecting the first printed circuit board to the second printed circuit board.BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Reference is now made to the accompanying figures in which:

[0058] Fig. 1 is a three-dimensional view of a battery pack in accordance with one embodiment;

[0059] Fig. 2 is a three-dimensional exploded view of the battery pack of Fig. 1 ;

[0060] Fig. 3 is a three-dimensional view of a heat-conducting plate of a battery enclosure of the battery pack of Fig. 1 ;

[0061] Fig. 4 is a side view of a portion of the heat-conducting plate illustrating fins thereof;

[0062] Fig. 5 is a three-dimensional view of an enclosure of a battery pack in accordance with an embodiment;

[0063] Fig. 6 is a schematic cross-sectional view of a layered structure of the heat-conducting plate of Fig. 5.

[0064] Fig. 7 is a schematic cross-sectional view of the heat-conducting plate of Fig. 5 illustrating a process of heat exchange;

[0065] Fig. 8 is a three-dimensional view of a battery pack in accordance with another embodiment;

[0066] Fig. 9 is an exploded three-dimensional view of the battery pack of Fig. 8;

[0067] Fig. 10 is a cross-sectional exploded view of the battery pack of Fig. 8;

[0068] Fig. 11 is a side, three-dimensional view of a portion of the battery pack of Fig. 8 illustrating internal components thereof;

[0069] Fig. 12 is a three-dimensional view of the battery pack of Fig. 8 with an enclosure thereof removed for illustration purposes;

[0070] Fig. 13 is another cross-sectional view of a portion of the battery pack of Fig. 8;

[0071] Fig. 14 is a three-dimensional exploded view of certain internal components of the battery pack of Fig. 8;

[0072] Fig. 15 is a three-dimensional exploded view of an assembly of battery packs in accordance with one embodiment; and

[0073] Fig. 16 is a three-dimensional view of an assembly of battery packs as described herein.DETAILED DESCRIPTION

[0074] Referring to Figs. 1-2, a battery pack (or battery “module”) is shown at 1 and includes one or more battery cells 2, a controller, also referred to as a battery management system 3 (BMS), operatively connected to the one or more battery cells 2, a cell holder 4 for securing the one or more battery cells 2 together, and a connector 5 operatively connected to the BMS 3. The connector 5 may be used as an interface to connect the battery pack 1 to a device in need of electrical power, such as, for instance, an electrical vehicle. The battery cells 2 are depicted here as being cylindrical. However, other shapes for battery cells, such as prismatic or pouch, are contemplated. An electric vehicle may include a plurality of the battery pack 1 combined together, in parallel to simply increase the storage capacity or in series to also increase the voltage.

[0075] Referring more particularly to Fig. 2, the battery pack 1 includes an enclosure 6 (Fig. 1) that is sized to contain the one or more battery cells 2, the BMS 3, and the cell holder 4. The enclosure 6 is herein provided in the form of a rectangular prism having six sides. The enclosure6 includes a main casing 7 having a plurality of interconnected side walls 8 defining multiple (e.g., 3, 4 or more) of the six sides of the enclosure 6. In some embodiments, the main casing 7 may define any number of sides of the enclosure 6. The main casing 7 may include a thermal insulating layer within the battery pack 1 to limit thermal exchange between the battery cells 2 and an environment outside the battery pack 1 . This may limit thermal energy loss during winter or cold environmental operating conditions. Other shapes of the casing and enclosure 6 are contemplated. A heat-conducting plate 10 defines at least some or all of the remaining sides of the enclosure 6. In this embodiment, the heat-conducting plate 10 defines two sides of the enclosure 6, but more or less than two sides may be defined by the heat-conducting plate 10. It will be appreciated that the enclosure 6 may have any suitable shapes and that the main casing7 and the heat-conducting plate 10 cooperate with one anotherto define the sides of the enclosure6. The main casing 7 may define any number of sides of the enclosure 6, the heat-conducting plate 10 may define at least part of the remaining sides of the enclosure 6.

[0076] The heat-conducting plate 10 may therefore have two functions: 1) it structurally defines a portion of the enclosure 6; and 2) it provides heat-conducting exchange relationship between the one or more battery cells 2 and an environment outside the enclosure 6. The heat- conducting plate 10 may therefore be constructed with materials having sufficient stiffness to be able to withstands loads imparted to the battery pack 1 during use. In the embodiment shown, the electronics of the battery pack 1 may be secured to the heat-conducting plate 10. This may allow the electronic components to be cooled by contact with the heat-conducting plate 10, similar to the battery cells. In other words, in the embodiment shown, the BMS 3 may be in heat exchange relationship (e.g., thermal contact) with the heat-conducting plate 10 to be cooled thereby. More detail about this configuration is presented below.

[0077] Referring now to Fig. 3, the heat-conducting plate 10 is described in further detail. In the embodiment shown, the heat-conducting plate 10 includes a first section 11 and a second section 12 secured to the first section 11 and extending generally transversally to the first section 1 1 . In the present embodiment, the first section 1 1 and the second section 12 include respectively a first plate 13 and a second plate 14. The first plate 13 and the second plate 14 may be made of aluminum or any other suitable material having both of a sufficient stiffness to provide the required structural integrity to the battery pack 1 and a sufficient heat conduction to be able to transfer heat from the one or more battery cells 2 as will be described further below. The material of the plates 13, 14 may have a thermal conduction of at least 10 W / mK. In some embodiments, the thermal conduction of the material of the plates 13, 14 is of at least 100 W / mK, preferably about 200 W / mK., The first and second plates 13, 14 of the heat-conducting play 10 are structurally loadbearing. In one particular embodiment of the present disclosure, the first plate provides a majority (i.e., more than 50%) of the structural support of the battery cells 2. Accordingly, in this embodiment, the first plate 13 of the heat-conducting plate 10 bears more than 50% of the total weight of the battery cells 2.

[0078] In the context of the present disclosure, the expression “structurally load-bearing” implies that the first and second plates 13, 14 are able to withstands loads imparted to the battery pack 1 during use. For instance, the loads may be acceleration / deceleration forces, torsion forces imparted by a frame of a vehicle to which the battery pack 1 is secured, flexion forces imparted by the frame, weight of the battery cells 2, and so on. A wall or plate may be considered to beload bearing if it retains its shape with the application of those loads during normal use of the battery pack 1 , without exhibiting any (or any non-negligible) plastic deformation. A wall or plate may be considered to have retained its shape if, although some deformations may be exhibited by the plate or wall, these deformations remain within the elastic regime of deformation of the plate or wall and are not permanent. These deformations do not impair operation of the battery pack 1 . For example, a thermal contact may be required between the battery cells and the heat- conducting plate 10. Some deformation may be acceptable when a flexible thermal interface material (TIM) is used between the battery cells and the heat-conducting plate 10. The TIM is typically a paste or a flexible film, which may accommodate up to approximately 100 micrometers. The stiffness of the heat-conducting plate is selected to be sufficient to keep the deformation below this value when subjected to the mechanical loads. The expression “structurally loadbearing” may imply that the plates 13, 14 or other component is able to withstand a flexion force, and / to withstand a torsion force, and / or to withstand a shearing force. The expression “withstand” implies that a deformation of the plates 13, 14 when subjected to the flexion force, torsion force, or shearing force, remains within the elastic regime.

[0079] It will be appreciated that, in some applications, it may not be required for the heat- conducting plate 10 to withstand loads and to be structurally load-bearing since it may be shielded from said loads by structural members (e.g., frame) of a vehicle for instance. In some cases, the battery pack 1 is to be used in static and non-movable applications not requiring the battery pack 1 to withstand loads greater than its own weight.

[0080] The structural nature of the heat-conducting plate 10 may in certain instances permit the removal of other components that would otherwise be required for a typical non-structural counterpart. For example, in addition to its use for heat transfer, the heat-conducting plate 10 may be used to structurally interconnect two different components of a vehicle or of another system.

[0081] Therefore, in addition to its thermal management function, the heat-conducting plate 10 described above, and any of the heat-conducting plates described herein, may be used as a casing portion of the battery module. This therefore may allow the removal of a component. The heat-conducting plates may form a bottom casing of the battery modules and be configured to support the weight of the cells and to protect components of the battery modules (e.g., cells, electronics, etc.) from forces applied to a frame of a vehicle for instance during normal use of said vehicle.

[0082] The first plate 13 may be monolithically integrated with the second plate 14 and therefore formed as a single part. For example, the first and second plates 13, 14 may be portions of a single plate, which is shaped (e.g., folded or otherwise formed) to provide the finished shape of the heat-conducting plate 10. In a particular embodiment, and as depicted, the first plate 13 and the second plate 14, even if monolithically formed, are non-planar and / or non-parallel and thereby be disposed at an angle (i.e., a non-zero angle or, stated differently, an angle that is nether zero nor 180 degrees) relative to each other. In other words, the first plate and the second plate lie in respective planes that intersect one other to define an angle between the first plate and the second plate. In the depicted embodiment, the first and second plates 13, 14 are substantially perpendicular to each other and form at least part of the base and a sidewall of the enclosure of the battery pack. The term “substantially perpendicular” in this context is understood to mean that the internal angle between the first and second plates 13, 14 is 90 degrees ± 10%, or more preferably 90 degrees ± 5%. This angle between the first and second plates 13, 14 can be created by bending a single, monolithically formed flat plate. The first plate 13 may be secured to the second plate 14 via brazing or welding. In some embodiments, brackets may be used to secure the first plate 13 to the second plate 14. The first plate 13 may be fastened to the second plate 14.

[0083] The term “monolithic” or “monolithically” as used herein is understood to mean that components formed in this manner are formed of a single part and therefore are integrated together in such as manner that they cannot be readily separated without causing damage or destroying the respective components.

[0084] The first plate 13 defines first grooves 13A and the second plates 14 defines second grooves 14A. The first and second grooves 13A, 14A communicate with one another and are sized to accept heat pipes 15 that longitudinally run along both of the first and second plates 13, 14. The heat pipes 15 have lengths extending from first ends on the first plate 13 to second ends on the second plate 14. More specifically, each of the heat pipes 15 has a section overlapping the first plate 13 and a second section overlapping the second plate 14. The heat pipes 15 may therefore define elbows 15A to follow a corner defined at the intersection of the first and second plates 13, 14. The heat pipes 15 may be any suitable heat pipes. The heat pipes 15 may transfer heat by a change of phase (e.g., from liquid to gaseous and vice-versa) of a fluid contained within the heat pipes 15. The heat pipes 15 may be adhered within the first and second grooves 13A, 14A using, for instance, a heat transfer adhesive, glue (e.g, epoxy), mechanical fastener, soldering, or by metallic brazing.

[0085] In the disclosed embodiment, the heat pipes 15 are flattened. This may increase a surface area for receiving heat from the battery cells compared to a rounded shape of the same cross-sectional area. Moreover, the flattened shape may limit a required thickness of the plates of the heat-conducting plate 10 since the grooves may be less deep than would be required in a configuration in which the heat pipes 15 are not flattened (e.g., rounded shape). In such a configuration, the heat pipes 15 remain concealed within the correspondingly shaped grooves. Whether flattened or not, in a particular embodiment the top surfaces of the heat pipes 15 are substantially flush with a surface of the heat-conducting plate 10 surrounding the grooves within which the heat pipes are located. As such, a volume of the enclosure containing the battery cells 2 may be free of the heat pipes 15. Put differently, there may be no heat pipes 15 located between the battery cells 2. All of the heat pipes 15 in the embodiment are located below (or above) the battery cells 2, and more specifically the heat pipes are recessed within the grooves formed in the surface(s) of the plates while remaining in direct contact with the battery cells.

[0086] Referring now to Fig. 3 and Fig. 4, a heat sink 50 is provided on the second section12 of the heat-conducting plate 10, which therefore acts as a condenser. In the present embodiment, the heat sink 50 is a monolithic part of the second plate 14. The second section 12, which includes the heat sink 50 and the second plate 14, may be manufactured from a single bloc of aluminum or any other suitable material. Monolith ically integrating the heat sink to the second plate 14 may reduce thermal resistance between the heat sink and the second plate 14. The heat sink 50 defines fins 14B secured to an outer side of the second plate 14; the outer side facing away from the one or more battery cells 2. The fins 14B of the heat sink 50 extend, in a particular embodiment, in a direction that is substantially normal to the second plate 14 and away therefrom. The fins 14B extend substantially transversally to the heat pipes 15. In the embodiment of Fig. 4, the fins 14B of the heat sink 50 extend longitudinally and parallel to the first plate 13. Alternatively, the fins 14B may extend vertically and perpendicularly to the first plate 13. The fins 14B may extend at any suitable angle. Having the fins 14B extending parallel to the first plate 31 may allow the fins 14B to receive heat from the heat pipes 15 at a plurality of locations along a length of their bases. The heat from the heat pipes 15 may be transferred to the second plate 14 by conduction, from the second plate 14 to the fins 14B by conduction, and from the fins 14B to an environment outside the enclosure 6 by convection.

[0087] A thickness T1 of the first plate 13 may be from about 1 mm to about 5 mm. A thickness T2 of the second plate 14 may be from about 1 mm to about 5 mm. The first and second plates 13, 14 may be made of aluminum or any other suitable material such as stainless steel or copper.

[0088] Referring now to Fig. 5, another embodiment of the heat-conducting plate is shown at 30. The battery pack 1 described above may thus be alternatively equipped with the heat- conducting plate 30 described below instead of with the heat-conducting plate 10 described above. The heat-conducting plate 30 includes a first section 31 and a second section 32 generally transverse to the first section 31 such that the heat-conducting plate 30 has a L-shape. The two sections 31 , 32 of the heat-conducting plate 30 may be structurally load-bearing as defined herein above. Moreover, the load-bearing characteristic of the heat-conducting plate 30 may allow the heat-conducting plate 30 to resist a force to rotate the two sections 31 , 32 one relative to the other. The first section 31 may define the bottom plate 17E of the enclosure 16 and the second section 32 may define the second end plate 17F of the enclosure 16. The first section 31 may be in contact with the one or more battery cell 2 (Fig. 2). In other words, the first section 31 is in heat exchange relationship with the one or more battery cells 2. Although the heat-conducting plate 30 depicted in Fig. 6 has a bend therein to form its L-shape, it is to be understood that the heat- conducting plate 30 as described herein may also be a flat (i.e., non-bent) plate. More detail about the heat-conducting plate 30 are presented in International patent application No.: PCT / CA2022 / 051825, the entire contents of which are incorporated herein by reference. In some embodiments, the heat-conducting plate 30 may act as an electrical busbar. This may be the case also for the heat-conducting plate 10 of Fig. 1. An electrical insulation layer may be disposed between the heat conducting plate 30 and the battery cells 2 to prevent electrical shortcut. This electrical insulation layer may be a thin sheet of material, such as Kapton™, or any other suitable polyimide film or other film, a thermal interface material (TIM), or a sprayed layer.

[0089] Referring more particularly to Fig. 6, the heat-conducting plate 30 has a layered structure 100. The layered structure 100 includes an outer envelope or casing that is composed of a first casing portion 101 and a second casing portion 102 (hereinafter simply referred to as first casing 101 and second casing 102). A cavity 103 is defined between the first casing 101 and the second casing 102. The first casing 101 is joined to the second casing 102 along a periphery of the heat-conducting plate 30. More specifically, a first peripheral flange of the first casing 101 abuts and is sealingly fixed to a second peripheral flange of the second casing 102 along a full uninterrupted perimeter of the first and second casings 101 , 102. In some embodiments, the perimeter may be interrupted by a filling tube, which may be used to pull a vacuum in the cavity 103, injecting water inside, and then sealed to maintain the partial vacuum inside. This filling tube may be located along the perimeter seal between the flanges. The first casing 101 is joined to the second casing 102 via the first and second peripheral flanges or peripheries. In anotherembodiment, the water is injected first and the two plates are secured into a low pressure environment, as described for example in International patent application No. PCT / CA2022 / 051825.

[0090] The structural load-bearing capabilities of the heat-conducting plate 30 may be provided by one or more of the first casing 101 and the second casing 102. In other words, the first casing 101 and / or the second casing 102 may have a thickness of at least from about 0.1 mm to about 5 mm, preferably from about 1 mm to about 5 mm, and may be made of aluminum or steel, or any other material able to render the plate structurally load-bearing. It will be appreciated that the thickness may be selected as a function of the structural characteristic and the thermal properties (e.g., thermal conductivity) of the material used. In some embodiments, at least a portion of the load-bearing capability of the heat-conducting plate 30 may be provided by the two flanges of the first casing 101 and second casing 102 being secured to one another and providing an effective thickness corresponding to a thickness of the flange of the first casing 101 plus a thickness of the flange of the second casing 102.

[0091] The heat-conducting plate 30 also includes, within the cavity 103 defined within the outer casing formed by the first and second casings 101 , 102, a core assembly including a first wicking layer 104 and a second wicking layer 105. The first wicking layer 104 is disposed adjacent the first casing 101 . The second wicking layer 105 is disposed adjacent the second casing 102. The core assembly further includes a vapor core 106 disposed between the first wicking layer 104 and the second wicking layer 105. Accordingly, a sandwiched core sub-assembly fills the cavity 103 defined between the inner surfaces of the walls of the first and second casings 102, the sandwiched core sub-assembly being composed of the first wicking layer 104, the vapor core 106, and the second wicking layer 105. In an alternative embodiment, only one wicking layer may be used, such that the core assembly includes a vapor core and one wicking layer. The wicking layer may be preferably positioned on the inner wall of the casing being in contact with the battery cells such that the liquid in the wicking layer is able to evaporate to absorb the heat generated by the battery cells. The portion of the casing in contact with the cells, and that faces the battery cells, may be thinner to facilitate heat transfer across the casing. Also, the opposite casing, which faces away from the battery cells, may be thicker to sustain the mechanical loads, provide the structural support, and may increase the thermal resistance between the cells and the environment to limit losses of thermal energy of the cells in cold temperatures (e.g., winter).

[0092] Referring now to Fig. 7, the different components of the heat-conducting plate 30 having been described above, the operation of the heat-conducting plate 30 is now described.

[0093] The heat-conducting plate 30 has a first end 30A, which may be in contact with the one or more battery cells 2 for receiving heat therefrom. A second end 30B may be in contact with a heat sink or cold plate to extract the heat. The heat-conducting plate 30 is operable to move the heat from the first end 30A to the second end 30B. To this end, the working fluid is present in liquid form in the first and second wicking layers 104, 105. When exposed to the heat, the working fluid evaporates in a gaseous phase and migrates, along arrows A1 , into the cavity 103, which contains the vapor core 106. The working fluid in gaseous phase then migrates along arrows A2 along the vapor core 106 towards the second end 30B of the heat-conducting plate 30. Since the second end 30B is colder than the first end 30A, the working fluid condensates back into a liquid phase and gets absorbed by the first and second wicking layers 104, 105 along arrows A3. Then, the working fluid moves, by capillary action, along the first and second wicking layers 104, 105 and migrates along arrows A4 back towards the first end 30A and the process starts over again. The heat-conducting plate 30 therefore removes heat from the first end 30A by evaporating the working fluid and transfers heat to the second end 30B by condensing the working fluid. These phase changes result in heat being moved from the first end 30A to the second end 30B. In an application where the component (i.e., battery pack or module) must be heated instead of cooled, then the inverse behavior and direction of the liquid and vapor flows are inverted, without any change to the plate structure.

[0094] Referring now to Figs. 8-10, another embodiment of a battery pack (battery module) is shown at 200. The battery pack 200 may be used for mobile applications, such as a battery for a low-speed vehicle. Such low-speed vehicles may be fully electric vehicles with a maximum speed of about 32 to 40 kilometers per hour. Low-speed vehicles include, for instance, golf cart, small trucks, delivery vans, and so on. In certain embodiments, the battery pack 200 may be able to provide a voltage of from 39 to 54 volts; an energy of about 2kWh (42Ah); a specific energy of about 150 Wh / kg; a continuous power of 50 A at 20 degrees Celsius; a peak current for five minutes of about 150 A; may be scalable either in series or in parallel; may be used at temperatures ranging from -20 degrees Celsius to 60 degrees Celsius.

[0095] The battery pack 200 includes battery cells 202 (Fig. 10), which may be Li-Ion cells, a cell holder 204 for securing the battery cells together, a connector 205 for connecting the battery pack 200 to a device in need of power or other similar modules, a battery management system220 operatively connected to the connector 205 and to the battery cells 202. The battery management system 220 is configured to manage power provided to and extracted from the battery cells 202 and is described in further detail below. The BMS 220 may also monitor the voltage, current, temperature of cells to detect failures, compute the State-of-Charge (SoC) of the module, and regulate a speed of the fan being in contact with the heat sink (not shown in the figures), and regulate the power of the heater. The connector 205 may be used as an interface to connect the battery pack 200 to a device in need of electrical power, such as, for instance, an electrical vehicle.

[0096] Much like the battery pack 1 of Fig. 1 , the battery pack 200 includes an enclosure 206 that is sized to contain the one or more battery cells 202, the battery management system 220, and the cell holder 204. The enclosure 206 is herein provided in the form of a rectangular prism having six sides. The enclosure 206 includes a main casing 207 having a plurality of interconnected side walls 8 defining multiple (e.g., 3, 4 or more) of the six sides of the enclosure 206. In some embodiments, the main casing 207 may define any number of sides of the enclosure 206. Other shapes of the enclosure 206 are contemplated.

[0097] The battery pack 200 includes a heat-conducting plate 210 defining at least some or all of the remaining sides of the enclosure 206. It will be appreciated that the enclosure 206 may have any suitable shapes and that the main casing 207 and the heat-conducting plate 210 cooperate with one another to define the sides of the enclosure 206. The main casing 207 may define any number of sides of the enclosure 206, the heat-conducting plate 210 may define at least part of the remaining sides of the enclosure 206.

[0098] Referring more particularly to Figs. 10-11 , the heat-conducting plate 210 includes a first section 21 1 and a second section 212 secured to the first section 21 1 and extending generally transversally to the first section 211. In the present embodiment, the first section 211 and the second section 212 include respectively a first plate 213 and a second plate 214. The first plate 213 and the second plate 214 may be made of aluminum or any other suitable material having both of a sufficient stiffness to provide the required structural integrity to the battery pack 200 and a sufficient heat conductivity to be able to transfer heat from the one or more battery cells 202 as will be described further below. In a particular embodiment, the first plate 213 and the second plate 214 are monolithically formed and together make up the heat-conducting plate 210. In one embodiment, for example, the first and second plates 213, 214 may form part of a single initialheat-conducting plate that is folded or otherwise formed to create the final shape and configuration of the heat-conducting plate 210.

[0099] The heat-conducting plate 210 includes heat pipes 217 (Fig. 11) mounted (e.g., bonded or otherwise attached in a thermally conductive manner) thereto. The heat pipes may be mounted to the first plate 213 and / or to the second plate 214. In one embodiment, the heat pipes have lengths that extending from first ends located on the first plate to second ends located on the second plate - i.e., the heat pipes span between the first and second plates to augment heat transfer therebetween.

[0100] In the depicted embodiment, the heat pipes 217 are received within grooves formed in the body of the heat-conducting plate 210. A heat sink 215 is provided at the second section 212 and is used to dissipate heat to an environment outside the battery pack 200. The heat sink 215 and the second plate 214 may be two portions of a single monolithic component. More specifically, heat is transferred from the battery cells 202 to the first section 211 of the heat- conducting plate 210 via conduction. The heat reaches the heat pipes and moves parallel to the first plate 213 until it reaches the second plate 214. The heat then moves transversally to the first plate 213 via the heat pipes 217. The heat is then transmitted to the second plate 214 via conduction and dissipated to the environment via convection between fins 215A of the heat sink 215 and ambient air. Heat transfer in a direction parallel to the heat pipes 217 may be substantially greater than heat transfer in a direction perpendicular to the first plate 213. The heat pipes 215 may therefore substantially direct a major portion of the heat extracted from the battery cells 202 to the heat sink 215. This may permit to keep the first plate 213 sufficiently cold to permit stacking of battery packs 200 (or, alternately, battery packs 1), as shown in Fig. 16, which is described below.

[0101] It will be appreciated that the heat sink 215 may be a separate component secured to the second plate 214 or, as in the present embodiment, monolithically integrated to the second plate 214. More specifically, in the disclosed embodiment, the fins 215A of the heat sink 215 monolithically protrude from the second plate 214. In the case where the heat sink 215 is a separate component, a thermal adhesive may be used to attach the heat sink 215 to the second plate 214 while minimizing a thermal resistance at an interface between these two components.

[0102] As illustrated in Fig. 10, in the embodiment shown, a fan 216 is mounted to the heat sink 215. The fan 216 is operable to induce a cooling air flow through the heat sink 215 andbetween the fins 215A. More specifically, the fan 216 may be oriented such as to push air in a first direction D1 away from the second section 212 of the heat-conducting plate 210. The fan 216 may drive an air flow in a direction opposite the first direction D1 . The fan 216 may be located at any other suitable locations. This may create a suctioning effect drawing air from sides of the heat sink 215 inducing a flow along a flow path denoted by dashed-lined arrows P1 . The flow path P1 extends between the fins 215A of the heat sink 215. The fan 216 may be operatively connected to the BMS 220. The BMS 220 may thus cause rotation of the fan 216 when more cooling is desired. The BMS 220 may further adjust a rotational speed of the fan 216 to vary a flow rate of air based on cooling needs of the battery pack 200. More specifically, the BMS 220 may cause an increase in a rotational speed of the fan 216 based on a temperature of the battery cells 202 or based on a temperature inside the enclosure 206. An ambient temperature outside the enclosure 206 may be used as input to determine a rotational speed of the fan 216. For instance, the BMS 220 may cause the fan 216 to rotate at an increased rotational speed in a hot day when the ambient temperature is above a given threshold. Different temperature sensors may be used to determine the temperature inside the enclosure 206 and, in some cases, to determine the ambient temperature. As described below, a temperature sensor may be directly integrated to the BMS 220.

[0103] The BMS 220 may also control the power of a heater 228 being in heat exchange relationship with the battery cells 202. In some embodiments, Li-ion cells may need to be heated (typically above 10 degrees Celsius) following a prolonged period of inactivity while being exposed to a cold temperature, such as when the vehicle is parked outside during winter. Heating the cells may prevent accelerated cell degradation also referred to as ageing. In the embodiment shown, the heater 228 is a heating layer disposed between the heat-conducting plate 210 and the battery cells 202. The heater 228 may include a resistive wire in a flexible sheet (e.g., Kapton™ or any other suitable material).

[0104] During operation of the battery pack 200, the battery management system 220 may generate heat. It may be required to dissipate that heat to the environment. In the present embodiment, the battery management system 220 is in heat exchange relationship with the heat- conducting plate 210.

[0105] Referring more particularly to Fig. 11 , in use, the battery management system 220 generates heat as its electronic components, including balancing resistance and metal oxide silicon field effect transistors to name few, are solicited. The heat-conducting plate 210 mayfurther be used to dissipate heat generated by the battery management system 220. Consequently, the BMS 220 is in heat exchange relationship with the first section 21 1 of the heat- conducting plate 210. Thus, the second section 212 of the heat-conducting plate 210 is in heat exchange relationship with the environment outside the enclosure for providing heat exchange between the environment and the battery cells 202 and the battery management system 220.

[0106] Referring now to Figs. 11-12, the BMS 220 is described in greater detail. The BMS 220 includes three printed circuit boards PCBs electrically connected to one another using a wireless connection. The three PCBs may extend transversally to one another. In other words, an assembly of the three PCBs may define two elbows, which may each define a 90 degrees angle. Other angles are contemplated. The BMS 220 includes a cell-management unit 221 , a balancing unit 222, and an inter-connection wirebond board 223. Each of the cell-management unit 221 , the balancing unit 222, and the inter-connection wirebond board 223 includes a respective one of the three PCBs. The cell-management unit 221 may be the main component of the BMS as it may control the balancing unit 222 and the cells 202 via the inter-connection wirebond board 223. The inter-connection wirebond board 223 may be used as an interface between the cells 202 and the cell-management unit 221 .

[0107] In the disclosed embodiment, at least a portion of the BMS 220 is in heat-exchange contact with the heat-conducting plate 210 to transfer heat generated by electronic components of the BMS 220 to the heat-conducting plate 210. In this embodiment, the portion of the BMS 220 in heat-exchange contact with the heat-conducting plate 210 includes the balancing unit 222. The PCB of the balancing unit 222 includes a board wall having a first face and a second face opposite the first face. Electronic components are disposed on the first face and the second face is oriented towards the first section 211 of the heat-conducting plate 210. The first and second faces of the PCB define to real-estate usable to secure electronic components thereto. The electronic components may include balancing resistances and metal oxide silicon field effect transistors mounted on the board wall. These components are known to generate heat during use. The second face of the PCB of the balancing unit 222 may thus be in heat-exchange contact with the first section 21 1 of the heat-conducting plate 210 to transfer heat thereto.

[0108] In the context of the present disclosure, the expression “in heat-exchange contact with” may imply a direct contact between two components. However, in some cases, it may be an indirect contact in which a thermal adhesive or other heat-conductive material is disposed between the two components. Hence, two components may be said to be in heat-exchangecontact with one another if they are secured together either directly or indirectly in such a way that heat transfer via conduction is possible between the two components. In the case of indirect contact, it is understood that a thickness of the thermal adhesive or any other intermediate material disposed therebetween is expected to be minimal and less than a thickness of the heat- conducting plate 10 or of the PCBs.

[0109] As illustrated in Fig. 11 , the balancing unit 222 and the inter-connection wirebond board 223 are each connected to the cell-management unit 221 via a wire-less connection 224. The wire-less connection includes header connectors, which may be referred to as a pin header or simply a header. Such wire-less connection includes a male pin header having one or more rows of pins mounted to a base and includes a female socket header defining one or more rows of pin-receiving apertures each sized to receive a respective one of the pins of the male pin header. The PCB of the cell-management unit 221 may include two male pin headers while PCBs of the inter-connection wirebond board 223 and the balancing unit 222 may each include a female socket header. Alternatively, the cell-management unit 221 may include two female socket headers each engageable by a respective one of two male pin headers defined respectively by the balancing unit 222 and the inter-connection wirebond board 223. Any combination is possible. Any suitable wire-less connection may be used. Alternatively, the wire-less connection may be provided by card edge connectors, flex PCB. Flex cables may be used in some embodiments. The PCB may be soldered directly in some embodiments.

[0110] Referring now to Figs. 13-14, the battery pack 200 may include safety features to protect the battery pack 200 in case of a thermal runaway event. A thermal runaway event is a chain reaction within one or more of the battery cells 202. Such a reaction may be challenging to stop after initiation. It may occur when the temperature inside the battery cell reaches a given threshold at which a chemical reaction occurs inside the battery cell. This chemical reaction contributes to produce more heat, which drives the temperature higher, causing further chemical reactions that create more heat, and so on. In some cases, the chemical reaction may generate gases. It may be required to expel those gases out of the enclosure 206.

[0111] In this embodiment, the enclosure 206 of the battery pack 200 defines a vent 218 defined through one of the interconnected walls of the enclosure 206 and providing fluid communication between an internal volume of the enclosure 206 and an environment outside the enclosure 206. In the present embodiment, the vent 218 is defined by the second plate 214 of the second section 212 of the heat-conducting plate 210, but may be defined by any of the side wallsof the enclosure 206 in an alternate embodiment. The vent 218 includes one or more apertures extending through the second plate 214. The vent 218 may extend through the heat sink 215. Hence, some of the fins 215A may be cut along a portion of their length to make space for the vent 218 and to minimize a flow resistance of a flow of gas exiting the enclosure 206.

[0112] A valve 219 may be in fluid communication with the vent 218 of the enclosure 206. The valve 219 has a closed configuration in which the volume is fluidly disconnected from the environment by the valve 219 and an open configuration in which the volume is in fluid communication with the environment through the valve 219 to evacuate hot gases out of the enclosure 206. The valve 219 may be a pressure relief valve configured to move from the closed configuration to the open configuration upon a pressure difference between a pressure inside the enclosure 206 and a pressure of the environment exceeding a pressure threshold. In an alternate embodiment, the valve 219 may be a controlled valve operatively connected to a controller, which may be the BMS 220.

[0113] A sensor 225, such as a pressure or a temperature sensor, may be mounted to the PCB of the cell-management unit 221 , or on any suitable PCB of the BMS 220. The sensor 225 may be printed on the PCB. This may provide space savings and may allow for a compact design of the BMS 220. The sensor 225 is operatively connected to the BMS 220 and configured to send signal indicative of a temperature or pressure inside the enclosure 206. The sensor 225 may be a hydrogen gas detector sensor able to detect a presence of hydrogen, which may be indicative of a thermal runaway event. The BMS 220 may be operatively connected to the controlled valve and configured to cause the opening of the controlled valve when the temperature is above a temperature threshold. However, in the depicted embodiment, the valve is a pressure valve that opens by itself automatically when the pressure in the battery pack 200 increases above a given threshold. The valve may thus be a non-controlled, passive device. As mentioned above, the BMS 220 may also be operatively connected to the fan 216 (Fig. 10) to control its rotational speed.

[0114] Referring now to Fig. 14, in the depicted embodiment, a cover 226 is disposed over the battery cells 202. The cover 226 may protect electrical connections to the battery cells 202 (e.g., wire bonds). The battery cells 202 may thus be located between the cover 226 and the heat- conducting plate 210, more specifically between the cover 226 and the first section 211 of the heat-conducting plate 210. The cover 226 overlaps the battery cells 202. The cover 226 may be made of a polymeric material or any other suitable material. The material of the cover 226 is selected to be able to locally sublime when exposed to a temperature above a temperaturethreshold. The temperature threshold is selected to be above a maximum operating temperature of the battery cells 202 and corresponds to a temperature at which the battery cells 202 may reach during a thermal runaway event. Thus, if one or more of the battery cells 202 experience a thermal runaway event, the cover 226 sublimes at one or more locations, each overlapping a respective one of the one or more battery cells 202 experiencing the thermal runaway event, to form local openings or passages in the cover. The cover 226, by locally subliming, opens one or more passages allowing gases generated by the battery cells 202 to be expelled out of the enclosure 206. More specifically, the one or more passages permit the gases to flow away from a remainder of the battery cells 202, which may prevent runaway of neighbouring battery cells. The gases may then be evacuated by the valve 219 and the fan 216. The cover 226 may thus allow the gases generated by the battery cells 202 to flow out of the cell holder 204 (Fig. 12) while limiting detrimental effects on surrounding battery cells.

[0115] In some embodiments, the cover 226 may provide a load path for forces applied to the outside of the battery pack 200 to be distributed substantially evenly on rims of the battery cells 202 while minimizing risk of damaging burst caps of the battery cells 202 or the wire bonds. The cover 226 may leave air channels between the cover 227 and a cell cover 227, which is described below. These air channels may permit gases to flow out of the battery pack in case of a thermal runaway event.

[0116] Still referring to Fig. 14, a cell cover 227 may be provided. The cell cover 227 may be disposed between the cover 226 and the battery cells 202. The cell cover 227 may be used to protect the battery cells 202 against electrical shorting in case of a collapsing or failure of the wirebond. A small gap may be provided the cell cover 227 and the battery cells 202 to allow electrical connections to the battery cells 202. In some embodiments, connections for thermal resistances may be provided in this small gap. These thermal resistances may be used to reduce a number of wired connections used. The cell cover 227 may be made using a PCB. In some embodiments, the thermal resistances may be directly provided on the cell cover 227 to eliminate the use of wire. Hence, the battery pack 200 may be free of wired connection. In some embodiments, the cell cover 227 and the inter-connection wirebond board 223 may be integrated in a single part.

[0117] Referring now to Fig. 15, an assembly of battery packs is shown at 300. The assembly 300 includes a plurality of the battery packs 200 described herein above with reference to Figs. 9-14. The assembly 300 includes an outer casing 301 defining a battery- receiving volume sizedto receive the battery packs 200. The outer casing 301 includes a top cover 302 for closing the battery-receiving volume. A support plate or base 303 may be located within the outer casing 301 and below the battery packs 200. It may be used as a structural member to withstand a weight of the battery packs 200. The base 303 may be made of a foam material to thermally isolate the heat-conducting plates 210 of the battery packs 200 from the environment.

[0118] In the disclosed embodiment, the battery packs 200 includes two columns of three rows totalling six battery packs, but any suitable number is contemplated. Flow passages 304 are provided between the rows and columns to permit adequate cooling air flow between them. Moreover, the outer casing 301 includes side walls 301 A defining apertures or openings 301 B. Each of the openings 301 B may be aligned with a respective one of the fans 216 of the battery packs 202. The second sections 212 of the battery packs 202 and their respective heat sinks 215 may each be facing a respective one of the openings 301 B for pushing hot air out of the outer casing 301. Thus, in use, cooling air flows generated by the fans 216 of the battery packs 202 may be used to draw air in and out of the outer casing 301 for cooling the battery packs 202. Apertures may be defined through the outer casing 301 , such as through the side walls 301 A. These apertures may be used to allow air to flow from the environment and into the outer casing 301.

[0119] Referring now to Fig. 16, an assembly 400 of battery packs 1 , 200 is depicted. The assembly includes a plurality of battery packs 1 , 200 as described above. In this embodiment, the battery packs 1 , 200 are vertically stacked one above the other and may be fastened to one another via their respective enclosures, e.g. enclosures 206. In some cases, the battery packs 1 , 200 may be secured to a support frame enclosing the battery packs 1 , 200. Such a configuration may facilitate connecting the battery packs 1 , 200 in series. Many other configurations are contemplated depending on the intended use of the battery packs 1 , 200. For instance, a horizontal stacking may be more suitable for ground vehicles while a vertical stacking may be more suitable for aircrafts, such as helicopters.

[0120] It is noted that various connections are set forth between elements in the preceding description and in the drawings. It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. A coupling between two or more entities may refer to a direct connection or an indirect connection. An indirect connection may incorporate one or more intervening entities. The term “connected” or "coupled to" may therefore include both direct coupling (in whichtwo elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements).

[0121] It is further noted that various method or process steps for embodiments of the present disclosure are described in the following description and drawings. The description may present the method and / or process steps as a particular sequence. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the description should not be construed as a limitation.

[0122] Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0123] While various aspects of the present disclosure have been disclosed, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the present disclosure. For example, the present disclosure as described herein includes several aspects and embodiments that include particular features. Although these particular features may be described individually, it is within the scope of the present disclosure that some or all of these features may be combined with any one of the aspects and remain within the scope of the present disclosure. References to “various embodiments,” “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. The use of the indefinite article “a” as used herein with reference to a particular element is intended to encompass “one or more” such elements, and similarly the use of the definite article “the” in reference to a particular element is not intended to exclude the possibility that multiple of such elements may be present.

[0124] The embodiments described in this document provide non-limiting examples of possible implementations of the present technology. Upon review of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made to the embodiments described herein without departing from the scope of the present technology. Yet further modifications could be implemented by a person of ordinary skill in the art in view of the present disclosure, which modifications would be within the scope of the present technology.

Claims

CLAIMS1 . A battery pack, comprising: an enclosure including interconnected walls; battery cells contained within the enclosure; a battery management system operatively connected to the battery cells and located within the enclosure; and a heat-conducting plate defining one or more of the interconnected walls of the enclosure, the heat-conducting plate having: a first section, the battery cells and the battery management system in heat exchange relationship with the first section; and a second section in heat exchange relationship with the first section, the second section in heat exchange relationship with an environment outside the enclosure for providing heat exchange between the environment and the battery cells and the battery management system.

2. The battery pack of claim 1 , wherein the battery management system has a printed circuit board having a board wall and electronic components secured to the board wall, the board wall having a first face and a second face opposite the first face, the electronic components mounted on the first face, the second face oriented towards the heat- conducting plate.

3. The battery pack of any one of claims 1 to 2, wherein a majority of a weight of the battery cells is supported by the first section of the heat-conducting plate.

4. The battery pack of any one of claims 1 to 3, wherein the first section includes a first plate and the second section includes a second plate, the first plate and the second plate lying in respective planes that intersect one other to define an angle between the first plate and the second plate, and the heat-conducting plate including heat pipes mounted to the first plate and / or the second plate.

5. The battery pack of claim 4, wherein the heat pipes are mounted to both the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

6. The battery pack of claim 4 or 5, wherein the first plate and the second plate are monolithically formed from a single heat-conducting plate that is folded to define the angle between the first plate and the second plate.

7. The battery pack of any one of claims 1 to 3, wherein the first section includes a first plate and the second section includes a second plate, the heat-conducting plate including heat pipes mounted to the first plate and / or the second plate.

8. The battery pack of claim 7, wherein the heat pipes are mounted to both the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.

9. The battery pack of any one of claims 4 to 8, further comprising a heat sink mounted to the second plate, the heat sink being in heat exchange relationship with the second section of the heat-conducting plate.

10. The battery pack of claim 9, comprising a fan mounted to the heat sink, the fan operable to induce a cooling air flow through the heat sink.1 1 . The battery pack of any one of claims 4 to 10, wherein the heat pipes are received within grooves defined by the first plate and by the second plate.

12. The battery pack of claim 1 1 , wherein the heat pipes are flattened.

13. The battery pack of any claim 11 or 12, wherein top surfaces of the heat pipes are substantially flush with a surface of the heat-conducting plate surround the grooves.

14. The battery pack of claim 13, wherein the top surfaces of the heat pipes are in direct contact with the battery cells.

15. A battery pack, comprising: an enclosure including interconnected walls, the enclosure having a vent defined through one of the interconnected walls and providing fluid communication between an internal volume of the enclosure and an environment outside the enclosure; battery cells contained within the enclosure;a heat-conducting plate defining one or more of the interconnected walls of the enclosure, the heat-conducting plate having a first section and a second section, the battery cells in heat exchange relationship with the first section and the second section being in heat exchange relationship with the first section, the second section being in heat exchange relationship with an environment outside the enclosure for providing heat exchange between the environment and the battery cells; and a valve in fluid communication with the vent of the enclosure, the valve having a closed configuration in which the internal volume is fluidly disconnected from the environment by the valve and an open configuration in which the internal volume is in fluid communication with the environment through the valve.

16. The battery pack of claim 15, wherein the valve is a pressure relief valve, the valve moving from the closed configuration to the open configuration in response to a pressure difference between a pressure inside the internal volume and a pressure of the environment exceeding a pressure threshold.

17. The battery pack of claim 15 or 16, wherein the vent is defined through the second section of the heat-conducting plate, the second section of the heat-conducting plate being disposed at an angle relative to the first section of the heat-conducting-plate.

18. The battery pack of claim 17, comprising a heat sink mounted to the second section, the heat sink in heat exchange relationship with the second section of the heat-conducting plate, and wherein the vent extends through the heat sink.

19. The battery pack of any one of claims 15 to 18, comprising a cover overlapping the battery cells, the battery cells disposed between the cover and the first section of the heat-conducting plate, the cover being made of a polymeric material that is configured to locally sublime when exposed to a temperature above a temperature threshold.

20. The battery pack of any one of claims 15 to 19, wherein the first section includes a first plate and the second section includes a second plate, the heat-conducting plate including heat pipes mounted to both of the first plate and the second plate, the heat pipes having lengths extending from first ends on the first plate to second ends on the second plate.21 . An assembly of battery packs, comprising:an outer casing defining a battery-receiving volume; and multiple battery packs contained within the battery-receiving volume, each of the battery packs having: an enclosure including interconnected walls; battery cells contained within the enclosure; and a heat-conducting plate defining one or more of the interconnected walls of the enclosure, the heat-conducting plate having: a first section supporting the battery cells, the battery cells being in heat exchange relationship with the first section; and a second section in heat exchange relationship with the first section; wherein the outer casing defines openings providing fluid communication between the battery-receiving volume and an environment outside the outer casing, the second sections of the battery packs each facing a respective one of the openings.

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