Tray and system for accommodating plurality of individual battery modules, and method for cooling plurality of battery modules accommodated in tray of such system

Abstract

The invention relates to a tray for accommodating a plurality of individual battery modules, the tray comprising a bottom wall and side walls defining a receiving space for the plurality of individual battery modules, and a coolant inlet and a coolant outlet, the tray having one or more inner walls, the one or more inner walls extend between the opposite side walls and subdivide the receiving space into a plurality of individual battery module receiving chambers, and each individual battery module receiving chamber is defined by a part of the bottom wall and by the one or more side walls and / or the one or more inner walls; wherein at least one of the side walls and / or at least one of the one or more inner walls comprises: a plate-shaped base part which is produced from a thermoplastic material and which comprises, on at least one plate side of the base part, wall channels for the flow of a coolant medium, wherein the wall channel is connected to the coolant inlet and to the coolant outlet such that a coolant medium can flow through the wall channel; and a layer based on a thermoplastic material bonded to the base part such that it covers and thereby closes the wall channels, in which the associated wall is oriented in the tray such that it faces the one or more battery module receiving chambers with its plate side having the layer bonded thereto. The invention also relates to a system comprising one or more of said trays and a cooling system and to a method for cooling a plurality of battery modules.

Description

Technical Field

[0001] In one aspect, the present invention relates to a tray for accommodating multiple individual battery modules. In another aspect, the present invention relates to a system for accommodating multiple individual battery modules, the system comprising one or more such trays. In yet another aspect, the present invention relates to a method for cooling multiple battery modules housed in a tray of such a system. Background Technology

[0002] Typically, battery modules (such as lithium-ion battery modules) involve a significant risk of thermal runaway in the event of a localized failure in one of the battery cells. Such localized failures can originate from mechanical shock (e.g., during an electric vehicle collision), dendrite formation and internal short circuits during overcharging, defects or impurities in the cell, or thermal abuse. In the event of thermal runaway, the battery module remains susceptible to reignition, making fire suppression extremely difficult and time-consuming.

[0003] Trays used for battery modules are typically made of cast aluminum.

[0004] The objective is to provide a tray for accommodating multiple individual battery modules, which has an improved cooling device. Another objective of the invention is to provide a tray for accommodating multiple individual battery modules, which has an integrated cooling device, and which can be manufactured in a simple and cost-effective manner.

[0005] Another object of the present invention is to provide a tray for accommodating multiple individual battery modules, wherein the possibility of catastrophic thermal runaway can be effectively reduced in the event of battery cell failure. The object is to provide a tray for accommodating multiple individual battery modules, wherein it is locally responsive to battery cell failure. Summary of the Invention

[0006] According to an aspect of the invention, one or more of the above-described objectives are achieved by a tray for accommodating a plurality of individual battery modules, the tray comprising a bottom wall and side walls, and a coolant inlet and a coolant outlet, the bottom wall and side walls defining a receiving space for the plurality of individual battery modules, wherein the tray has one or more inner walls extending between opposing side walls and subdividing the receiving space into a plurality of individual battery module receiving chambers, each of the plurality of individual battery module receiving chambers being defined by a portion of the bottom wall and by one or more side walls and / or one or more inner walls.

[0007] Wherein at least one of the sidewalls and / or at least one of the one or more inner walls comprises:

[0008] - A plate-shaped base component, said plate-shaped base component being made of a thermoplastic material and including, on at least one plate side of the base component, wall channels for the flow of a coolant medium, wherein the wall channels are connected to a coolant inlet and a coolant outlet, such that the coolant medium can flow through the wall channels, and

[0009] - A layer based on a thermoplastic material, preferably a layer based on a polyolefin, particularly preferably a film based on a polyolefin, is bonded to a base component such that it covers and thereby seals the wall channels, wherein the relevant walls are oriented in the tray such that they face one or more battery module receiving chambers with their plate sides having the layer bonded thereto.

[0010] In another aspect, the present invention relates to a system for accommodating multiple individual battery modules, comprising:

[0011] - One or more pallets according to the invention; and

[0012] - Cooling system, which includes:

[0013] - Supply lines that connect to the coolant inlet of each of one or more trays;

[0014] - Discharge lines, which connect to the coolant outlet of each of one or more trays; and

[0015] - Flow generating devices, such as pumps, are used to generate a circulating flow of coolant medium through supply lines, wall channels, and optionally underground channels, as well as discharge lines.

[0016] In another aspect, the present invention relates to a method for cooling a plurality of battery modules housed in a tray of a system according to the invention, comprising:

[0017] - Using a flow generating device, the flow of coolant medium is driven through wall channels and optional underground channels in one or more trays.

[0018] Several preferred features of the invention are disclosed below. These features are applicable to trays, systems, and methods according to the invention.

[0019] The effect of the tray, system, and method according to the invention is that, due to the construction of at least one of the sidewalls and / or at least one of the inner walls having a base component having a wall channel covered by a layer based on a thermoplastic material (preferably polyolefin), a localized battery cell failure (which causes (local) overheating of the associated battery cell) causes localized melting of the thermoplastic-based layer, thereby creating a localized crack (or hole, opening, or perforation) in the thermoplastic-based layer near the failure location of the cell. As a result, a spray of coolant medium immediately emerges from the wall channel, passes through the localized opening, and counteracts the battery cell, thereby locally reducing the temperature of the battery cell and passively dissipating heat like a localized fire extinguisher. This helps prevent thermal runaway from further propagating within the cell and subsequently to other cells and modules. Attached Figure Description

[0020] The invention is described below with reference to the accompanying schematic diagrams, which illustrate examples of the invention, and wherein the same reference numerals denote the same or similar elements.

[0021] Figure 1a An isometric view of an example of a tray according to aspects of the present invention is shown, wherein five battery modules are received in the receiving space of the tray. Figure 1b It shows Figure 1a An isometric view of the tray, in which the receiving space of the tray is completely occupied by the battery module. Figure 1c It shows Figure 1a and 1b A more detailed isometric view of the individual battery module receiving chamber of the tray.

[0022] Figure 2 A more detailed isometric view of an example of one of the bottom wall, one of the side wall, and one of the inner wall of a tray according to aspects of the present invention is shown.

[0023] Figure 3 An isometric view of another example of one of the inner walls of a tray according to aspects of the present invention is shown.

[0024] Figure 4 A cross-sectional view of a portion of a tray according to aspects of the present invention is shown.

[0025] Figure 5 A close-up of a portion of one and / or one or more inner walls of a tray according to aspects of the invention is shown in the event of overheating of the battery module cells.

[0026] Figure 6 An example of a system according to another aspect of the present invention is illustrated schematically.

[0027] Figure 7An example of a method according to another aspect of the present invention is illustrated schematically.

[0028] Figure 8a , 8b A test apparatus for testing the concept of the system and method of the present invention is disclosed. Detailed Implementation

[0029] The invention is illustrated below with a detailed description. Unless otherwise defined or specified, all terms shall be construed as having the technical meaning as understood by those skilled in the art.

[0030] Unless otherwise specified, all parameter ranges include the endpoints of the range and all values ​​between the endpoints. When used in this specification and claims, the terms "comprise" and "comprising," and variations thereof, mean that the specified feature, step, or integer is included. These terms should not be construed as excluding the presence of other features, steps, or components.

[0031] A tray is defined as an open container with a bottom wall and side walls for accommodating multiple battery cells. The bottom wall is defined as the wall that closes the bottom surface of the tray and, together with the side walls, forms a receiving space. The side walls are defined as the walls that close the sides of the tray and, together with the bottom wall, form a receiving space. Typically, a tray has one bottom wall and four side walls, defining a rectangular receiving space. An inner wall is defined as a wall that subdivides the receiving space formed by the bottom wall and side walls. The inner walls extend between opposing side walls. In an embodiment, there are at least two inner walls of the tray that extend perpendicularly to each other, thereby subdividing the receiving space into at least four battery module receiving chambers in a matrix shape of at least two by at least two battery module receiving chambers. If there are several inner walls extending between other inner walls, then all inner walls in one direction are considered to extend between opposing side walls. The inner walls subdivide the receiving space into receiving chambers or cavities for receiving battery modules or battery cells. These receiving chambers may be arranged in a matrix as follows: a series of parallel inner walls extending in a first direction between a first pair of opposing sidewalls, and a series of parallel inner walls extending in a direction perpendicular to the first series and between a second pair of opposing sidewalls, the second pair of opposing sidewalls being perpendicular to the first pair of opposing sidewalls.

[0032] A battery module is defined as a single battery cell or an assembly of multiple interconnected battery cells.

[0033] At least one of the one or more inner walls may comprise: a plate-like base component having the wall channels on both plate sides of the base component; and a respective thermoplastic-based layer bonded to either plate side of the base component to cover and thereby close the respective wall channels. This allows for cooling of the battery module on both sides of the respective inner wall.

[0034] A bottom channel is defined as a channel in the bottom wall. A wall channel is defined as a channel in the side wall or inner wall. A plate side is defined as a plate-like side of the base component, opposite to the edge of the plate-like base component.

[0035] The wall channel can have multiple branches, allowing the coolant medium to flow through these branches during use. This allows for better distribution of the coolant medium across the entire surface of the wall. A branch is defined as a sub-channel arising from the main channel.

[0036] The bottom wall may also include the plate-like base component, which is made of a thermoplastic material and includes a bottom channel on at least one plate side of the base component for the flow of a coolant medium, wherein the bottom channel is connected to a coolant inlet and a coolant outlet, allowing the coolant medium to flow through the bottom channel. The bottom wall also includes a thermally conductive layer, preferably a thermally conductive film, which is bonded to the base component such that it covers and thereby seals the bottom channel, wherein the bottom wall is oriented such that its inner plate side faces the receiving space, the inner plate side having the layer bonded thereto. For this embodiment, the flow generating device of the system according to the invention may also be arranged to generate a circulating flow of the coolant medium through a supply line, through the bottom channel, and a discharge line. In this respect, the method according to the invention may include using a flow generating device to drive the flow of the coolant medium through the bottom channel in one or more trays.

[0037] At least 20% of the plate surface of each wall portion surrounding each battery module chamber may be free of wall channels and optionally free of bottom channels to serve as an abutment for positioning the battery module in the relevant chamber. A wall portion is defined as a part of the bottom wall, side wall, and / or inner wall surrounding each battery module (receiving) chamber.

[0038] The inner walls of the tray can extend perpendicularly to each other and can subdivide the receiving space into at least four battery module receiving chambers in a matrix shape of at least two by at least two battery module receiving chambers.

[0039] Each inner wall may contain a groove such that two inner walls can interlock perpendicularly with each other at any given time, wherein the first of the two inner walls extends through the groove in the second of the two inner walls, and wherein the second of the two inner walls extends through the groove in the first of the inner walls.

[0040] In each inner wall, at least one wall channel may extend within the inner wall, remaining unaffected by the groove. The groove is defined as an opening or recess, preferably a narrow opening or recess, in a side wall or inner wall for receiving a portion of another side wall or inner wall.

[0041] As mentioned above, the present invention relates to a system including a cooling system comprising a supply line and a discharge line and a flow generating device (such as a pump), the supply line being connected to a coolant inlet of a tray and the discharge line being connected to a coolant outlet of the tray, the flow generating device being used to generate a circulating flow of coolant medium through the supply line, through wall channels, and optionally underground channels, and through the discharge line.

[0042] A coolant inlet is defined as an inlet present in the tray that allows coolant medium to enter one or more wall channels (and one or more bottom channels) within the tray. It is conceivable that each side wall and optionally each inner wall (and optionally the bottom wall) has a separate coolant inlet or that a specific coolant inlet is provided from the tray. A coolant outlet is defined as an outlet present in the tray that allows coolant medium to exit one or more wall channels and one or more bottom channels within the tray. It is conceivable that each side wall and optionally each inner wall (and optionally the bottom wall) has a separate coolant outlet or that a specific coolant outlet is provided from the tray.

[0043] The coolant can be present under pressure, which will exhibit a certain amount of elastic stretching in the thermoplastic-based layers of the sidewalls and optionally the inner walls (and optionally the thermally conductive layer of the bottom wall). This will ensure improved contact with the battery cell and lower thermal contact resistance during use. The cooling system can be configured to pressurize the coolant medium, for example, at pressures between 0.5 and 20 Barg. The thermoplastic-based layers and optionally the thermally conductive layer are elastically stretched due to the pressurized coolant medium.

[0044] Coolant media are defined as media used for cooling. Examples of them are (pressurized) coolant fluids, such as coolant gases, coolant liquids, or mixtures of coolant liquids or gases. Additionally, coolant gels may be mentioned. Preferably, the coolant media is a mixture of water and ethylene glycol. Ethylene glycol is commonly used to lower the freezing point of water; it is not typically used in its pure form because it is very viscous. For mixtures of water and ethylene glycol, there is a balance between viscosity (less ethylene glycol) and a lower freezing point (more ethylene glycol). The exact ratio of water to ethylene glycol can be determined by those skilled in the art and depends on the operating temperature and the desired viscosity. A mixture of about 1:1 water:ethylene glycol (about 50% ethylene glycol) is commonly used and is suitable for this invention.

[0045] The system according to the invention may further include a coolant medium reservoir connected via a valve to a supply line or a discharge line, such that the coolant medium flows through a wall passage and optionally an underground passage when the valve is opened. The coolant medium reservoir is defined as a reservoir containing coolant medium and optionally a fire extinguishing agent, located outside the tray.

[0046] Fire extinguishing agents are defined as agents that suppress fires, such as chemical compounds that interfere with free radicals (primarily hydrogen, hydroxyl, or oxygen radicals) present during the combustion phase of a flame, like potassium citrate. In cases where a battery pack not only exhibits thermal runaway but also eventually ignites and forms a fire, such fire extinguishing agents may also be present in addition to coolant media.

[0047] The system may include a pressure sensor for detecting a pressure drop in the wall channel and optionally in the underground channel, the pressure drop being caused by localized melting of a layer based on a thermoplastic material (preferably based on polyolefin), the localized melting being caused by heat generated by the battery module in the tray, wherein the pressure sensor is connected to a valve such that the valve opens when the pressure sensor detects the pressure drop.

[0048] The coolant medium may comprise a pressurized coolant fluid, preferably a liquid coolant, or a pressurized mixture of liquid and gaseous coolant. Examples of coolant media are dielectric liquid coolants that do not cause short circuits when leaked; examples include transformer oil, perfluoroalkane, and pure water. Preferred coolant media comprise water and ethylene glycol, and optionally a fire extinguishing agent.

[0049] Using a cooling system, the coolant medium can be pressurized, causing the thermoplastic-based layers to be elastically stretched due to the pressurized coolant medium, thereby increasing heat transfer from the battery module to the coolant medium due to the increased contact between the layers and the battery module.

[0050] As mentioned above, the plate-like base components of the bottom wall, side walls, and optionally inner walls are made of thermoplastic materials, such as polyolefin materials.

[0051] The thermoplastic material may be selected from the group consisting of, for example, polypropylene or thermally conductive polycarbonate with low specific gravity, UL94 V0 polyolefin compounds such as those with high specific strength and specific stiffness, UL94 V0 high-flow engineering thermoplastic compounds with good adhesive compatibility for thin internal components, and any of the families of polyester compounds with low-temperature ductility for impact absorbers. LEXAN 945 and CYCOLOY 7240 may be mentioned as examples thereof. The thermoplastic material may contain one or more of the following: additives and / or stabilizers such as antioxidants, UV stabilizers, pigments, dyes, adhesion promoters, and flame retardants such as organophosphate / ester compounds (e.g., piperazine pyrophosphate / ester, piperazine polyphosphate / ester and combinations thereof), mixtures and combinations thereof of organophosphate compounds (e.g., phosphoric acid, melamine pyrophosphate / ester, melamine polyphosphate / ester, melamine phosphate / ester), and zinc oxide, and / or fillers such as fibers or talc. For example, fiber-filled polyolefins can be used as thermoplastic materials. Possible fiber materials may include at least one of glass, carbon, aramid, or plastic, preferably glass. The fiber length can be chopped, long, short, or continuous. Specifically, long glass fiber-filled polypropylene (e.g., STAMAX available from SABIC) TM It can be used as a thermoplastic material. Long fibers can be defined as having an initial fiber length of at least 3 mm before molding. For example, talc-filled PP can also be used because of its good shrinkage / warpage behavior.

[0052] The thermoplastic-based layer present on the sidewalls and optionally the inner wall is preferably a polyolefin-based film, but may also be an injection-molded or otherwise prepared component, such as a housing. The polyolefin may be, for example, an ethylene-based polymer or a propylene-based polymer. Preferably, the polyolefin has a peak melt temperature (T0) of at least 100°C, preferably at least 120°C or at least 140°C. p,m According to ASTM D3418 (2008), the test result was obtained.

[0053] The thermoplastic-based layer can be a layer based on a polyethylene halide polymer, preferably a film based on a polyethylene halide polymer, such as polyvinyl chloride (PVC), a thermoplastic chloropolymer having repeating vinyl chloride units, or polyvinyl fluoride (PVF), a thermoplastic fluoropolymer having repeating vinyl fluoride units. The thermoplastic-based layer / film can also be one or more of the following materials: i) polyetherimide (PEI) (e.g., ULTEM). ® ), ii) Modified resins (e.g., NORYL) consisting of amorphous blends of polyphenylene oxide (PPO) or polyphenylene oxide (PPE) resin with polystyrene. ®iii) Polycarbonate (PC) (e.g., LEXAN®), iv) Semi-crystalline materials of polybutylene terephthalate (PBT) and / or polyethylene terephthalate (PET), optionally blended with polycarbonate (PC) (e.g., VALOX). ® (v) Polyamide (PA). Preferably, the thermoplastic material has a peak melt temperature (T0) of at least 100°C, preferably at least 120°C or at least 140°C. pm According to ASTM D3418 (2008), the test result was obtained.

[0054] The polyolefin-based layer can be selected from the group consisting of: biaxially oriented polypropylene (BOPP) film, biaxially oriented polyethylene (BOPE) film, or film comprising one or more layers, preferably at least a core layer and two outer layers.

[0055] Ethylene-based polymers may be, for example, ethylene homopolymers or copolymers of ethylene with one or more α-olefins, preferably wherein the α-olefin comprises 1-10 carbon atoms, more preferably wherein the α-olefin is selected from 1-butene, 1-hexene, or 1-octene. For example, an ethylene-based polymer may contain ≥80.0% by weight, preferably ≥90.0% by weight, more preferably ≥95.0% by weight, of a structural moiety derived from ethylene, relative to the total weight of the ethylene-based polymer. For example, an ethylene-based polymer may contain ≤20.0% by weight, preferably ≤10.0% by weight, more preferably ≤5.0% by weight, of a structural moiety derived from 1-butene, 1-hexene, or 1-octene.

[0056] Ethylene-based polymers can, for example, have a density of ≥870 kg / m³. 3 Preferred values ​​are ≥870 and ≤975 kg / m³. 3 More preferably ≥900 and ≤975 kg / m 3 Even more preferred is ≥945 and ≤970 kg / m 3 The density was determined according to ASTM D792 (2008).

[0057] Ethylene-based polymers may, for example, have a melt mass flow rate of ≥0.1 and ≤10.0 g / 10 min, preferably ≥0.1 and ≤5.0 g / 10 min, more preferably ≥0.2 and ≤3.5 g / 10 min, as determined according to ASTM D1238 (2013) at 190°C under a load of 2.16 kg.

[0058] The polypropylene-based membrane may comprise a propylene homopolymer, a propylene-ethylene copolymer, or a propylene-ethylene-C4 terpolymer or a propylene-ethylene-C6 terpolymer, wherein the copolymer or terpolymer has an ethylene content of up to 4.0% by weight, such as between 3.0 and 4.0% by weight, or up to 1.5% by weight in another embodiment, based on the weight of the copolymer or terpolymer; wherein the homopolymer, copolymer, or terpolymer has: i) a Mw / Mn ratio in the range of 4.0 to 12, preferably 5.0 to 12, where Mw represents the weight-average molecular weight and Mn represents the number-average molecular weight, and wherein Mw and Mn are measured according to ASTM D6474-12; ii) an XS ratio in the range of 1.0 to 8.0% by weight, preferably 1.0 to 6.0% by weight, where XS represents the amount of xylene-soluble matter as measured according to ASTM D 5492-10; and iii) an ethylene content in the range of 1 to 10% by weight. Melt flow rate in the range of dg / min, measured according to ISO 1133-1 (2011) (2.16 kg / 230℃).

[0059] Polyolefin films can be, for example, bidirectionally oriented films (BO films), wherein the orientation is introduced in the solid state. For example, BO films can be... p,m Oriented at a temperature at least 10°C lower. The BO film may, for example, have a thickness of ≥50 and ≤500 μm, preferably ≥50 and ≤300 μm. The BO film may be oriented in the longitudinal direction to an orientation degree of ≥5.0 and ≤25.0. The BO film may be oriented in the transverse direction to an orientation degree of ≥5.0 and ≤25.0. The BO film may be oriented in both the longitudinal and transverse directions to an orientation degree of ≥5.0 and ≤25.0. In this context, the orientation degree is defined as the ratio of the film size after orientation to the film size before orientation in both the longitudinal and transverse directions. BO films can be produced by: casting melt extrusion film, cooling the film to a temperature higher than T... p,m The film is then stretched at a temperature at least 10°C lower, both longitudinally and transversely. Stretching can be performed simultaneously in both directions, or sequentially, first in the longitudinal direction and then in the transverse direction, or first in the transverse direction and then in the longitudinal direction.

[0060] The thermoplastic-based layer can be a multilayer film containing an aluminum core layer between two polyolefin-based outer layers. Such a laminate offers the advantages of excellent thermal conductivity, dissipating heat from localized hot spots and preventing or delaying localized overheating and melting of the outer thermoplastic-based layers. The thermoplastic-based layers ensure easy attachment of the thermally conductive layer to the sidewalls or inner walls, for example, by melting the polyolefin of the thermally conductive layer to the thermoplastic material of the sidewalls or inner walls. The aluminum core layer can have a thickness between 20 and 100 micrometers. The aluminum core layer is preferably a perforated layer, but it can also be a solid layer (i.e., without perforations). In the former case, localized perforations (cracks, openings, or punctures) can form in the event of localized melting, leading to localized release (jetting) of the coolant medium present in the wall channels. When using polypropylene-based materials for the sidewalls and / or bottom walls, and when using aluminum-containing layers, it is preferable that the sides of the layers attached to the sidewalls and / or bottom walls are also based on polypropylene to ensure optimized bonding.

[0061] The amount of thermoplastic material in the thermoplastic material-based layer may be, for example, at least 50% by weight, at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, or at least 95% by weight, relative to the total thermoplastic material-based layer.

[0062] The amount of thermoplastic material in the thermoplastic material-based layer can be, for example, 10 to 90% by weight, relative to the total thermoplastic material-based layer.

[0063] The thermoplastic-based layer can be a multilayer film containing an aluminum core layer between two thermoplastic-based outer layers, wherein the amount of thermoplastic material in the multilayer film is 10 to 90% by weight and the amount of aluminum in the multilayer film is 10 to 90% by weight, relative to the total multilayer film.

[0064] The amount of polyolefin in the polyolefin-based layer may be, for example, at least 50% by weight, at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, or at least 95% by weight, relative to the total polyolefin-based layer.

[0065] The amount of polyolefin in the polyolefin-based layer may be, for example, 10 to 90% by weight, relative to the total polyolefin-based layer.

[0066] The polyolefin-based layer can be a multilayer film containing an aluminum core layer between two polyolefin-based outer layers, wherein the amount of polyolefin in the multilayer film is 10 to 90% by weight and the amount of aluminum in the multilayer film is 10 to 90% by weight, relative to the total multilayer film.

[0067] In embodiments where one or more bottom channels exist within a bottom wall, the thermally conductive layer present on the bottom wall is preferably a thermally conductive film, but can also be a component, such as a housing, prepared by injection molding or other methods. The thermally conductive layer may have the same material discussed above for layers based on thermoplastic materials (preferably polyolefins). The thermally conductive layer may be a multilayer film comprising an aluminum core layer between two outer polyolefin-based layers, or an outermost aluminum layer and an inner layer based on a thermoplastic material (preferably polyolefin). Such a laminate has the advantage that the aluminum core layer provides excellent thermal conductivity to dissipate heat from localized hot spots, thereby preventing or delaying localized overheating and melting of the outer thermoplastic material (preferably polyolefin-based) layer. The thermoplastic-based layer ensures that the thermally conductive layer is easily fixed to the bottom wall, for example, by melting the polyolefin of the thermally conductive layer to the thermoplastic material of the bottom wall. The aluminum core layer may have a thickness between 20 and 100 micrometers. The aluminum core layer is preferably a solid layer (i.e., without perforations), however, it can also be a perforated layer. In the latter case, localized melting can lead to the formation of localized cracks, resulting in the localized release (jetting) of the coolant medium present in the bottom channel beneath the heat-conducting layer.

[0068] The thermally conductive layer may contain the same material as discussed above for layers based on thermoplastic materials (preferably based on polyolefins).

[0069] The thermally conductive layer may contain at least 50% by weight, at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, or at least 95% by weight of thermoplastic material, relative to the total thermally conductive layer.

[0070] The thermally conductive layer may contain 10 to 90% by weight of thermoplastic material, relative to the total thermally conductive layer.

[0071] The thermally conductive layer may be a multilayer film comprising an aluminum core layer between two outer layers based on thermoplastic materials, or an outermost aluminum layer and an inner layer based on thermoplastic materials, wherein the amount of thermoplastic material in the multilayer film is 10 to 90% by weight and the amount of aluminum in the multilayer film is 10 to 90% by weight, relative to the total multilayer film.

[0072] The thermally conductive layer may contain at least 50% by weight, at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, or at least 95% by weight of polyolefin, relative to the total thermally conductive layer.

[0073] The thermally conductive layer may contain 10 to 90% by weight of polyolefin, relative to the total thermally conductive layer.

[0074] The thermally conductive layer may be a multilayer film comprising an aluminum core layer between two polyolefin-based outer layers or an outermost aluminum layer and an inner polyolefin-based layer, wherein the amount of polyolefin in the multilayer film is 10 to 90% by weight and the amount of aluminum in the multilayer film is 10 to 90% by weight, relative to the total multilayer film.

[0075] The accompanying drawings are shown below in more detail.

[0076] Figure 1a and Figure 1b An isometric view of an example of a tray 100 according to aspects of the present invention is shown. The tray 100 is arranged to accommodate a plurality of individual battery modules 10 and includes a bottom wall 101 and side walls 103 defining a receiving space 105 for receiving the plurality of individual battery modules 10. The tray 100 has one or more inner walls 107 extending between opposing side walls 103 and subdividing the receiving space 105 into a plurality of individual battery module receiving chambers 111. Each battery module receiving chamber 111 is defined by a portion of the bottom wall 101 and by one or more side walls 103 and / or inner walls 107. The tray 100 also includes a coolant inlet 113 and a coolant outlet 115.

[0077] Figure 1a and Figure 1b An example of a tray 100 is shown, wherein the inner walls 107 of the tray 100 extend perpendicularly to each other, thereby subdividing the receiving space 105 into thirty-six battery module receiving chambers 111 in a matrix shape of six by six battery module receiving chambers 111. Figure 1a In the process, five battery modules 10 are received in the receiving space 105 of the tray 100, wherein... Figure 1b In the tray 100, all the individual battery module receiving chambers 111 of the receiving space 105 are occupied by individual battery modules 10.

[0078] Figure 1c A more detailed isometric view of a separate battery module receiving chamber 111 of the tray 100 is shown, which is defined by a portion of a bottom wall 101 and by one or more side walls 103 and / or one or more inner walls 107, wherein the battery module 10 is placed into the battery module receiving chamber 111 from the top of the tray 100.

[0079] Figure 2A more detailed isometric view is shown of an example of one of the bottom wall 101, one of the side walls 103, and one of the inner walls 107 of the tray 100. The bottom wall 101 comprises a plate-shaped base component 121 made of thermoplastic material. At least one of the side walls 103 and / or at least one of the inner walls 107 comprises a plate-shaped base component 131 made of thermoplastic material. The plate-shaped base component 131 comprises a wall channel 133 for the flow of a coolant medium on at least one plate side 131a of the base component 131. The wall channel 133 is connected to a coolant inlet 113 and a coolant outlet 115 (not shown) such that the coolant medium can flow through the wall channel 133 to cool the battery module 10. The wall channel 133 may have multiple branches such that the coolant medium flows through multiple branches during use. Each wall channel 133 of at least one of the sidewalls 103 and / or one or more inner walls 107 may be directly connected to the coolant inlet 113 and the coolant outlet 115, or may be connected to the coolant inlet 113 and the coolant outlet 115 via one or more additional wall channels 133. At least one of the sidewalls 103 and / or at least one of the inner walls 107 further comprises a layer 135 based on a thermoplastic material (preferably based on polyolefin), preferably a polyolefin-based film, which is bonded to the base component 131 such that it covers and thereby closes the wall channel 133, wherein the relevant sidewall 103 and / or inner wall 107 is oriented in the tray 100 such that it faces one or more battery module receiving chambers 111 with its plate side 131a having the layer 135 bonded thereto. Each inner wall 107 includes one or more slots 137 such that two inner walls 107 can interlock perpendicularly with each other at any time, wherein a first of the two inner walls 107 extends through a slot 137 in a second of the two inner walls 107, and wherein a second of the two inner walls 107 extends through a slot 137 in a first of the inner walls 107. In each inner wall 107, at least one wall channel 133 extends in the inner wall 107, remaining unaffected by the slot 137.

[0080] Figure 3 An isometric view of another example of one of the inner walls 107' of the tray 100 is shown, wherein the inner wall 107' comprises: a plate-like base member 131 having wall channels 133 on both plate sides 131a, 131b of the base member 131; and respective thermoplastic-based layers 135, which are bonded to either plate side 131a, 131b of the base member 131 to cover and thereby close the respective wall channels 133.

[0081] Figure 4A cross-sectional view of a portion of another embodiment of the tray 100 is shown, wherein two battery modules 10 are received in respective battery module receiving chambers 111, the battery module receiving chambers 111 including a bottom wall 101, a side wall 103, and an inner wall 107' of a base component 121. The side wall 103 includes wall channels 133 covered by a thermoplastic material layer 135 on the plate side 131a of the base component 131, and the inner wall 107' includes wall channels 133 covered by a thermoplastic material layer 135 on both the plate side 131a and the plate side 131b of the base component 131.

[0082] Figure 5 A close-up of a portion of one of the sidewalls 103 and / or one or more inner walls 107, 107' of the tray 100 is shown in the event of cell overheating in the battery module 10. In addition to being arranged to cool the battery module 10 via one of the sidewalls 103 and / or one or more inner walls 107, 107', one of the sidewalls 103 and / or one or more inner walls 107, 107' is also arranged as an internal spray system in the event of cell overheating in the battery module 10, which produces a spray of coolant medium 143 flowing through the wall channel 133. For example, the coolant medium 143 contains water and ethylene glycol, and optionally a fire extinguishing agent. Localized cell failure causes the associated cell to overheat, resulting in localized melting of layer 135, thereby creating localized perforations 141 in the thermoplastic-based layer 135. As a result, coolant spray 143 immediately emerges from the wall channel 133, passes through the perforations 141, and counteracts the cell, thereby locally reducing the temperature and helping to prevent thermal runaway.

[0083] The width and / or depth of the channels (123, 133) may be selected depending on several factors, such as the size of the tray 100, the thickness of the walls (101, 103, 107 / 107'), the thickness of the thermally conductive layer 125 covering the bottom channel 123 and / or the thickness of the thermoplastic material layer 135 covering the wall channel 133, the type of material used for the walls and the layers covering the walls, and their melting, solidification, and / or crystallization characteristics.

[0084] In the implementation, the width of the channels (123, 133) is between 0.1 and 5.0 cm, such as between 0.5 and 1.0 cm. In the implementation, the depth of the channels (123, 133) is between 0.5 and 1.0 cm.

[0085] The thermoplastic material layer 135 can be attached / bonded to the sidewall 103 and / or the inner wall 107 / 107' by any means known to those skilled in the art, such as heatstake, laser, or even ultrasound. When present, the thermally conductive layer 125 can be attached / bonded to the bottom wall 101 in a similar manner.

[0086] Figure 6 An example of a system 200 according to another aspect of the invention is schematically illustrated. The system 200 is arranged to accommodate a plurality of individual battery modules 10 (not shown) and includes one or more trays 100 according to aspects of the invention and a cooling system 201. The cooling system 201 includes a supply line 203, a discharge line 205, and a flow generating device 207 (such as a pump). The supply line 203 is connected to a coolant inlet 113 of each of the one or more trays 100, the discharge line 205 is connected to a coolant outlet 115 of each of the one or more trays 100, and the flow generating device 207 is used to generate a circulating flow of coolant medium through the supply line 203, through a wall channel 133 (and optionally an underground channel 123), and through the discharge line 205. System 200 also includes a coolant medium reservoir 209 and / or an external connection 213 for a fire responder, which is connected via a valve 211 to a supply line 203 or a discharge line 205 such that coolant medium 143 flows through wall channel 133 (and optionally underground channel 123) when valve 211 is opened. In the event of a localized battery cell failure causing overheating of the relevant cell, layer 135 is locally melted, resulting in a localized perforation 141 in the thermoplastic-based layer 135. Coolant spray 143 and optional extinguishing agent 143 immediately emerge from wall channel 133, pass through perforation 141, and counteract the battery cell, thereby locally reducing the temperature and helping to prevent thermal runaway. System 200 also includes a pressure sensor 215 for detecting a pressure drop in the wall channel 133 (and optionally the underground channel 123) caused by localized melting of the thermoplastic-based layer 135, which is caused by heat generated by the battery module 10 in the tray 100. The pressure sensor 215 is communicatively connected to a valve 211 such that the valve 211 opens when the pressure sensor detects a pressure drop. Cooling system 201 is configured to pressurize a coolant medium, causing the thermoplastic-based layer 135 (and optionally the thermally conductive layer 125) to be elastically stretched due to the pressurized coolant medium.

[0087] Figure 7An example of method 300 according to another aspect of the invention is illustrated schematically. Method 300 is arranged to cool a plurality of battery modules 10 housed in a tray 100 of a system 200 according to the invention. Method 300 includes a driving step 301: using a flow generating device 207, causing a flow of coolant medium and optionally a fire extinguishing agent through one or more wall channels 133 (and optionally underground channels 123) in the tray 100. The coolant medium comprises a pressurized coolant fluid, preferably a coolant liquid, or a pressurized mixture of coolant liquid and gas. For example, the coolant medium comprises water and ethylene glycol, and optionally a fire extinguishing agent. Using the cooling system 201, the coolant medium is pressurized such that a thermoplastic-based layer 135 is elastically stretched due to the pressurized coolant medium, thereby increasing heat transfer from the battery modules 10 to the coolant medium due to the increased contact between the layer 135 and the battery modules 10.

[0088] To test the operation of the wall channel 133 of the system and method of the present invention, the following proof-of-concept test was performed. In the proof-of-concept test, a dedicated testing device was used instead of the tray 100 according to the present invention. This testing device is shown in… Figure 8a , 8b The special equipment 400 comprises a support plate 401 made of thermoplastic material, the support plate 401 having dimensions of 305 mm × 305 mm. This support plate 401 simulates the wall (side wall 103 or inner wall 107 / 107') of the tray 100 according to the invention. The thermoplastic support plate 401 has a thickness of 4 mm and is made of polypropylene (STAMAX) filled with long glass fibers. TM (Available from SABIC) To simulate the wall channel 133 covered with a thermoplastic-based layer 135, an off-the-shelf thermoplastic bag 402 was used. This thermoplastic bag 402 is made of a 51-micron-thick thermoplastic-based layer and has the following dimensions: 305 mm × 229 mm. The thermoplastic bag 402 is obtained from Cole-Palmer® (ESS GD0912-7000 sampling bag with combination valve, 3L) and is a gas sampling bag made of 2-micron-thick Tedlar® material with a solid seam. The thermoplastic bag 402 includes a polypropylene combination valve (3 / 16'' OD on / off valve stem) and an integrated PTFE silicone diaphragm. The thermoplastic bag 402 has a 3L volume and has valves for attaching coolant inlet 113 and coolant outlet 115. DuPont TMThe Tedlar® material is polyvinyl fluoride (PVF), a thermoplastic material, with a melting point close to 190°C. The coolant inlet 113 of the thermoplastic bag 402 is attached to a supply line 203 (garden hose) via a pressure regulator 404 to supply regular water as the coolant medium 143. The thermoplastic bag 402 is connected to the water hose via a regulator with pressure control between 35-70 kPa. The thermoplastic bag 402 is then placed on top of a support plate 401 and clamped in place using four aluminum metal strips 405, which allow the formation of five extended sections containing the pressurized coolant medium 143. These five extended sections simulate wall channels 133. The metal strips 405 are 6.35 mm thick, 6.35 mm wide, and 305 mm long, and are spaced approximately 70 mm apart. These strips 405 are clamped using eight 2-inch QUICK-GRIP resin spring clips (not shown), one at each end of each strip. After securing the thermoplastic bag 402 to the support plate 401, a flame torch 406 was used to simulate thermal runaway of the battery module 10. The flame torch 406 was an air-fed methane flame torch, with its flame and distance adjusted to achieve a surface temperature of approximately 800°C. The flame torch 406 was held at a distance of approximately 12 cm from the thermoplastic bag 402, and within seconds of heating the thermoplastic bag 402, localized perforations 141 were achieved through localized melting of the thermoplastic bag, resulting in a significant spraying of the coolant medium 143. This proof-of-concept test clearly demonstrates the effectiveness of the system and method according to the invention.

[0089] In practicing the invention claimed, those skilled in the art can understand and implement other variations of the disclosed embodiments from a study of the drawings, disclosure, and appended claims. The scope of the invention is defined by the appended claims. One or more objects of the invention are achieved by the appended claims.

[0090] List of reference numerals

[0091] 10: Individual battery module

[0092] 100: Pallet

[0093] 101: Bottom wall

[0094] 103: Sidewall

[0095] 105: Receiving Space

[0096] 107 / 107': Inner wall

[0097] 111: Battery module receiving chamber

[0098] 113: Coolant Inlet

[0099] 115: Coolant Outlet

[0100] 121: Plate-shaped foundation components

[0101] 123: Bottom Channel

[0102] 125: Thermal conductive layer

[0103] 131: Plate-shaped foundation components

[0104] 131a / 131b: Plate side

[0105] 133: Wall Passage

[0106] 135: Layers based on thermoplastic materials

[0107] 137: slot

[0108] 141: Perforation

[0109] 143: Coolant medium

[0110] 200: System

[0111] 201: Cooling System

[0112] 203: Supply pipeline

[0113] 205: Discharge pipeline

[0114] 207: Flow generating device

[0115] 209: Coolant Medium Reservoir

[0116] 211: Valve

[0117] 213: External connection for fire responder

[0118] 215: Pressure sensor

[0119] 300: Method

[0120] 301: Driving Steps

[0121] 400: Test Equipment

[0122] 401: Support plate

[0123] 402: Thermoplastic bags

[0124] 403: Water Connector

[0125] 404: Pressure Regulator

[0126] 405: Metal strip

[0127] 406: Flame Burner

Claims

1. A tray for receiving a plurality of individual battery modules, the tray comprising a bottom wall and side walls, and a coolant inlet and a coolant outlet, the bottom wall and side walls defining a receiving space for the plurality of individual battery modules, wherein the tray has one or more inner walls extending between opposing side walls and subdividing the receiving space into a plurality of individual battery module receiving chambers, each of the plurality of individual battery module receiving chambers being defined by a portion of the bottom wall and by one or more side walls and / or one or more inner walls. At least one of the sidewalls and / or at least one of the inner walls comprises: - A plate-shaped base component, said plate-shaped base component being made of a thermoplastic material and including wall channels on at least one plate side of said base component for the flow of a coolant medium, said wall channels being connected to the coolant inlet and the coolant outlet, such that the coolant medium can flow through the wall channels, and - A layer based on a thermoplastic material, preferably a layer based on a polyolefin, particularly preferably a film based on a polyolefin, is bonded to the base component such that it covers and thereby closes the wall channel, wherein the relevant wall is oriented in the tray such that it faces one or more battery module receiving chambers with its plate side having the layer bonded thereto.

2. The pallet of claim 1, wherein at least one of the one or more inner walls comprises: a plate-like base member having the wall channel on both plate sides of the base member; and a respective thermoplastic-based layer bonded to either plate side of the base member to cover and thereby close the respective wall channel.

3. The tray according to any one of the preceding claims, wherein the wall channel has a plurality of branches such that the coolant medium flows through the plurality of branches during use.

4. The tray according to any one of the preceding claims, wherein the bottom wall also includes the plate-like base member, the plate-like base member being made of a thermoplastic material and having a bottom channel for the flow of a coolant medium on at least one plate side of the base member, wherein the bottom channel is connected to the coolant inlet and the coolant outlet such that the coolant medium can flow through the bottom channel, the bottom wall further including a thermally conductive layer, preferably a thermally conductive film, which is bonded to the base member such that it covers and thereby closes the bottom channel, wherein the bottom wall is oriented such that it faces the receiving space with its inner plate side having the layer bonded thereto.

5. The tray according to any one of the preceding claims, wherein at least 20% of the plate surface of each wall portion surrounding each battery module chamber is free of the wall channels to serve as a coupling for positioning the battery module in the relevant chamber.

6. The tray according to any one of the preceding claims, wherein the inner walls of the tray, extending perpendicularly to each other, subdivide the receiving space into at least four battery module receiving chambers in a matrix shape of at least two by at least two battery module receiving chambers. Each of the inner walls includes a groove such that the two inner walls can interlock perpendicularly with each other at any time, wherein the first of the two inner walls extends through the groove in the second of the two inner walls, and wherein the second of the two inner walls extends through the groove in the first of the inner walls. in, In each inner wall, at least one wall channel extends within the inner wall, remaining unaffected by the groove.

7. A system for accommodating multiple individual battery modules, comprising: - One or more trays according to any one of the preceding claims; and - Cooling system, which includes: - Supply lines, which are connected to the coolant inlet of each of the one or more trays; - A discharge line, which is connected to the coolant outlet of each of the one or more trays; and - A flow generating device, such as a pump, is used to generate a circulating flow of the coolant medium through the supply line, through the wall channel, and through the discharge line.

8. The system of claim 7, further comprising a coolant medium reservoir connected via a valve to the supply line or to the discharge line such that the coolant medium flows through the wall passage when the valve is opened.

9. The system of claim 8, further comprising a pressure sensor for detecting a pressure drop in the wall channel, the pressure drop being caused by localized melting of the thermoplastic-based layer, the localized melting being caused by heat generated by the battery module in the tray, wherein the pressure sensor is connected to the valve such that the valve opens when the pressure sensor detects the pressure drop.

10. The system according to any one of claims 7-9, wherein the cooling system is configured to pressurize the coolant medium such that the thermoplastic-based layer is elastically stretched due to the pressurized coolant medium.

11. A method for cooling a plurality of battery modules housed in a tray of a system according to any one of claims 7-10, comprising: - Using the flow generating device, the flow of coolant medium is driven through the wall channels in the one or more trays.

12. The method of claim 11, wherein the coolant medium comprises a pressurized coolant fluid, preferably a coolant liquid, or a pressurized mixture of coolant liquid and gas. Preferably, the coolant medium comprises water and ethylene glycol, and optionally a fire extinguishing agent.

13. The method of claim 11 or 12, wherein the coolant medium is pressurized using the cooling system such that the thermoplastic-based layer is elastically stretched due to the pressurized coolant medium, thereby increasing heat transfer from the battery module to the coolant medium due to increased contact between the layer and the battery module.

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