Battery storage system for automobile

Abstract

A method of manufacturing a battery package for an automobile includes forming a battery enclosure and releasably connecting a cover to an enclosure opening thereby defining the package, the forming of the battery enclosure including: (i) forming an integral seamless liner defining a battery storage cavity and a coolant channel facing the storage cavity, the liner optionally: compression forming; performing injection molding; or thermoforming, comprising: heating a continuous seamless plastic sheet, attaching the plastic sheet to an inner surface of a mold formed into a battery storage cavity by vacuum adsorption, and cooling the plastic sheet; (ii) providing an outer housing, which is optionally: (a) inductive for charging the battery cells within the enclosure; and (b) configured for radio frequency signal transmission therethrough; (iii) filling the core body cavity with foam; forming a coolant inlet port and a coolant outlet port through the housing; (v) forming an electronic feed-through port through the housing.

Description

Technical Field

[0001] The present invention relates to a battery storage system for a vehicle. Background Art

[0002] Electrified vehicles differ from conventional motor vehicles in that electrified vehicles are selectively driven by one or more electric motors powered by a battery pack. The electric motor can replace the internal combustion engine to drive the electrified vehicle or can supplement the internal combustion engine to drive the electrified vehicle. Examples of electrified vehicles include hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), fuel cell vehicles (FCV), and battery electric vehicles (BEV).

[0003] The battery pack is a relatively high-voltage traction battery that selectively powers the electric motor and other electrical loads of the electrified vehicle. The battery pack may require cooling or heating. The battery pack includes an array of interconnected battery cells that store the energy to power the electrical loads. These arrays are typically housed within an enclosure.

[0004] Composite enclosure solutions for storing batteries can utilize multi-layered oriented glass and carbon fiber, metal stampings, or thick plastic structures. The manufacturing techniques for such enclosures allow for limited production volumes and are difficult to scale up. Summary of the Invention

[0005] A method of manufacturing an enclosure for encapsulating a battery in a vehicle is disclosed, the method comprising forming a housing and releasably connecting a lid to an opening of the housing to define the enclosure, the housing having a housing wall comprising: a bottom wall, a first side wall and a second side wall extending upwardly from the bottom wall to a top end of the housing, and a first end wall and a second end wall extending upwardly from the bottom wall to the top end, wherein the top end defines the opening of the housing, and wherein each of the housing walls has an inner surface and an outer surface, the inner surface such that the housing defines a storage cavity for storing battery cells, and the inner surface and the outer surface being spaced apart from each other to define a core cavity, wherein forming the housing comprises: (i) forming a liner, the liner being an integral seamless liner that defines the inner surface of each of the housing walls and forms the storage cavity; and forming a coolant passage facing the storage cavity and fluid-sealed with the storage cavity, wherein the coolant passage is formed along the inner surface of one or more of the housing walls, wherein the liner is formed by one of: compression molding; injection molding; or thermoforming, thermoforming comprising: heating a continuous seamless plastic sheet, attaching the plastic sheet to a mold shaped as the storage cavity via vacuum suction, and cooling the plastic sheet; (ii) providing an outer housing that defines the outer surface of each of the housing walls, wherein the outer housing is one or more of: (a) inductive for charging battery cells within the enclosure; (b) configured to allow radio frequency signals to pass through; (iii) filling the core cavity with foam; (iv) forming a coolant inlet port and a coolant outlet port through the housing such that coolant is configured to be conveyed through the coolant passage; (v) forming an electronic feedthrough port through the housing. The liner can be a material capable of withstanding direct exposure to flame, i.e., a flame retardant material, preferably having a UL94 V0 rating at the minimum thickness of the liner. The foam between the liner and the outer cladding can be a flame retardant foam or an inherently flame retardant foam, such as silicone foam. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 A side view of a battery pack mounted under a vehicle according to an embodiment is provided;

[0007] Figure 2 Provided is Figure 1 a bottom view of the battery pack;

[0008] Figure 3 A system for thermally regulating a battery pack according to an embodiment is schematically shown;

[0009] Figure 4 Shown is from Figure 3 a perspective view of a battery pack of a powertrain;

[0010] Figure 5 Shown is a sectional view taken along line III in Figure 4 ;

[0011] Figure 6 shows Figure 5 a cross-sectional view without a cover, battery, or coolant channel cover;

[0012] Figure 7 is a perspective view of a battery pack enclosure that can be manufactured according to an embodiment;

[0013] Figure 8 shows a coolant tube for cooling battery cells in an enclosure according to an embodiment;

[0014] Figure 9 shows according to an embodiment Figure 7 a cross-sectional view of a battery cell enclosure;

[0015] Figure 10 shows coolant channels formed in the lining of an enclosure according to an embodiment;

[0016] Figure 11 shows a process for forming a lining according to an embodiment; and

[0017] Figure 12 is a flowchart showing a method of manufacturing a battery cell enclosure according to an embodiment. DETAILED DESCRIPTION

[0018] In the following, the terms "battery", "cell", and "battery cell" may be used interchangeably and may refer to any of a variety of different battery types, chemistries, and configurations, including but not limited to lithium-ion (e.g., lithium iron phosphate, lithium cobalt oxide, other lithium metal oxides, etc.), lithium-ion polymer, nickel-metal hydride, nickel-cadmium, nickel-hydrogen, nickel-zinc, silver-zinc, or other battery types / configurations. The term "battery pack" as used herein refers to a plurality of individual batteries contained within a single-piece or multi-piece enclosure, with each battery electrically interconnected to achieve the voltage and capacity required for a particular application. The term "electric vehicle" as used herein may refer to a fully electric vehicle (also known as an EV), a plug-in hybrid vehicle (also known as a PHEV), or a hybrid vehicle (also known as an HEV), where a hybrid vehicle is a vehicle that utilizes multiple propulsion sources, one of which is an electric drive system.

[0019] Figure 1 and Figure 2 respectively provide a side view and a bottom view of a vehicle 5 with a battery pack 11 mounted below the vehicle 5. The vehicle 5 may have an information reader 6, such as a dashboard information display, which is operatively coupled to a vehicle controller 7. The controller 7 may be configured to determine the remaining charge within the battery pack 11 and provide an indication of the remaining charge within the battery pack 11 on the information reader 6. The drawings show heat flowing out of the vehicle in directions 13, 15, and 17. Figure 1 andFigure 2 The battery pack configuration shown is for illustrative purposes only, and the present invention is equally applicable to other configurations. Generally, the location of the battery pack depends on a series of design criteria, including but not limited to: the size and weight of the battery pack to achieve the desired performance, the selection of battery cells, the distribution of the battery pack weight to achieve the desired vehicle performance, and the limitations resulting from vehicle size, the position of the vehicle chassis support frame members, the size and configuration of the passenger compartment (e.g., the number of seats), the configuration of the trunk and engine compartment, etc. In addition, some vehicles may use multiple battery packs. The design of using multiple battery packs may be due to the use of multiple drive motors or simply to achieve the desired weight distribution.

[0020] Reference Figure 3 , an integrated system 30 can be provided within the vehicle 5 for thermally regulating the battery pack 11. The integrated system 30 can include the battery pack 11 housed within the enclosure 60. The pump 40 can pressurize the coolant flow 110 that flows through the pipe 45 outside the enclosure 60 via the channel 90 or pipe 285 (discussed in more detail below) within the enclosure 60. The coolant 110 carrying the heat discharged from the battery pack 11 removes heat from the coolant 110 via the heat exchanger 55, which is part of the vehicle air conditioning circuit 57 of the vehicle 5. For the cooling of the battery pack 11, the heat generating elements within the enclosure are the battery cells, and the heat is continuously removed to maintain the desired operating range, for example, from +20 degrees Celsius to +39 degrees Celsius. The advantage of the enclosure 60 of the disclosed embodiment is that it isolates the internal battery pack 11 from external influences (e.g., overheating or overcooling), thus allowing for more stringent thermal regulation.

[0021] Now refer to Figure 4 and Figure 5 , an additional aspect of the battery pack 11 is shown, which includes an enclosure 60 that provides an internal area or storage cavity 64 for housing the battery cells 18. The enclosure 60 can house two battery cells 18 within the storage cavity 64. The battery cells 18 are located in adjacent arrays 18A, 18B. In other examples, the enclosure 60 can house more than two or less than two battery arrays of the battery cells 18 within the storage cavity 64. The enclosure 60 can include a tray or lower housing 70 and a cover or upper housing 74 that rests on the top end 70T of the lower housing 70. Both the lower housing 70 and the upper housing 74 can provide a part of one of the side walls 78 and end walls 79 of the enclosure 60. Alternatively, the side walls 78 and end walls 79 are entirely provided by the lower housing 70 (see Figure 7) In this case, the tray can be collectively referred to as the cover body. Inside the storage cavity 64, the battery unit 18 can be rested on the channel cover 82, which can be a heat exchange plate supported on a support surface 84 provided by the lower cover body 70. A mechanical fastener 86 can fix the channel cover 82 to the lower cover body 70. Although described as a mechanical fastener 86, other types of fastening devices can also be used. Other mechanical fasteners (not shown) can be used to fix the battery unit 18 to the channel cover 82. The channel cover 82 can be a metal or metal alloy. In a specific example, the heat exchange plate is made of aluminum. The channel cover 82 and other examples can be other materials selected for promoting heat conduction other than metals or metal alloys. In a specific example, the heat exchange plate is made of aluminum.

[0022] A thermal interface material (TIM) can be positioned between the battery unit 18 and the channel cover 82. The TIM can help maintain thermal contact between the battery unit 18 and the channel cover 82. The TIM can be a pre-cured sheet, uncured liquid, cured liquid, gel, or other types. The TIM can be a silicone-based material with conductive fillers, an acrylic-based material with conductive fillers, or other types.

[0023] The lower cover body 70 can provide a part of the coolant channel 90 associated with the battery unit 18. The lower cover body 70 includes a recessed area 92 to provide the coolant channel 90. The recessed area 92 can have a trapezoidal cross-sectional profile. Alternatively, the coolant channel 90 can have a U-shaped or V-shaped cross-sectional profile. The recessed area 92 can be recessed relative to the support surface 84 that interfaces with the channel cover 82. The recessed area 92 can be provided by a bottom plate 94 and opposing side walls 98, 102. The recessed area 92 may not extend to the side walls 78 and end wall 79 of the lower cover body 70, or it can extend to the side walls 78 and end wall 79. Extending the recessed area 92 to the side walls 78 and end wall 79 can provide a coolant channel that interfaces with the bottom and lateral sides of the battery unit 18. In the assembled battery pack 11, the channel cover 82 covers the recessed area 92 to provide the top surface 106 of the coolant channel 90. In particular, the channel cover 82 can extend across the coolant channel 90 from side wall 98 to side wall 102.

[0024] For the purposes of this disclosure, top and bottom are with reference to the orientation of the battery pack shown in the figure. Other orientations of the battery pack 11 are possible, and in some orientations, the top surface 106 can become the bottom surface of the coolant channel 90, and the bottom plate 94 can become the top surface of the channel. Therefore, top and bottom should not be considered as restricting the battery pack 11 to a specific orientation.

[0025] A liquid or gas coolant 110 can move through coolant channels 90. The support surface 84 can include a seal compatible with the coolant 110, such as an ethylene propylene diene monomer (EPDM) seal. This configuration prevents the coolant 110 from moving between the support surface 84 and the channel cover 82. The seal can be a press-in seal, a carrier gasket seal, a foam seal, an RTV silicone seal, etc. The coolant 110 can exchange thermal energy with the channel cover 82. The coolant 110 can absorb thermal energy from the channel cover 82, which can be generated during the operation of the battery cell 18. Since the thermal energy moves from the battery cell 18 through the channel cover 82 to the coolant 110 within the coolant channel 90, the coolant 110 can cool the battery cell 18. The coolant channels 90 can extend below two battery cells 18 within the storage cavity 64. Thus, the coolant 110 moving through the coolant channels 90 can pass below two battery cells 18 of the battery pack 11. The coolant channels 90 can be divided into separate channels. That is, for example, the coolant channels 90 can include a first channel associated with one of the battery cells 18 and a separate second channel associated with another array.

[0026] Now referring to Figure 6 and continuing to refer to Figure 5 , the lower housing 70 can be a composite structure of the enclosure 60. In particular, the lower housing 70 can include a core 112 sandwiched within a core cavity 112A, the core being located between an inner layer or inner surface (also referred to as a liner) 114 and an outer layer or outer surface 116 (also referred to as an outer housing). At least one insert 120 can be disposed between the inner layer 114 and the outer layer 116 of the lower housing 70. Both the lower housing 70 and the upper housing 74 can be composite structures. Alternatively, one of the tray or the lid is a composite structure and the other of the tray or the lid is not a composite structure. Yet alternatively, another region of the enclosure 60 is a composite structure, such as a sidewall of the enclosure 60 that is separate from the lower housing 70 and the upper housing 74. The core 112 can be a foam. The foam can be a closed-cell high-density foam. Other example materials suitable for use as the core 112 can include honeycomb structures, balsawood, meta-aramid materials (such as materials sold under the trade name ), etc. The core 112 can be produced by a variety of methods, which may depend on the material composition of the core 112. Exemplary methods can include extruding the core 112 and molding the core 112.

[0027] Although the inner layer 114 and the outer layer 116 are described as single layers, additional layers can be employed, for example, to increase the strength of the lower housing 70. Additionally, the material composition of the outer layer 116 can be different from that of the inner layer 114. For example, the inner layer 114 can have a material composition suitable for interfacing with the storage cavity 64 of the battery pack 11, and the outer layer 116 can have a material composition suitable for interfacing with the external environment surrounding the battery pack 11. The outer layer 116 can be, for example, a high-temperature-resistant epoxy resin, such as an epoxy resin sold under the trade name / name Duralco TM 4460

[0028] In this example, the insert 120 is disposed within the slot 122 of the core 112. The insert 120 can be a polymer-based material. In particular, an exemplary insert 120 is a ultra-high molecular weight (UHMW) polyethylene material. In this example, the insert 120 is a monolithic structure. In another example, the insert 120 has a plurality of separate and independent inserts. In other examples, the insert 120 is a metal or metal alloy. The material and shape of the insert 120 can be selected to reduce or eliminate creep and maintain the seal between the channel cover 82 and the lower housing 70.

[0029] In Figure 5 the assembled battery pack 11, the mechanical fastener 86 extends through the inner layer 114 to threadedly engage an area of the insert 120. The engagement of the mechanical fastener 86 with the insert 120 clamps the channel cover 82 against the support surface 84 of the lower housing 70. In other examples, the insert 120 can be used to secure other battery components, in place of or in addition to the channel cover 82.

[0030] In Figure 5 the cross-section of the coolant channel 90 shown, the lower housing 70 provides a portion of the perimeter of the coolant channel 90, while the channel cover 82 provides the remaining portion of the perimeter of the coolant channel 90. Thus, the entire perimeter of the coolant channel 90 is provided by the lower housing 70 and the channel cover 82.

[0031] Figure 7 is a perspective view of the battery pack 11 configured as a multi-piece package, where the lower housing 70 has a U-shaped cross-section and can be referred to as the lower housing as shown, or generally as the housing. Figure 7 The upper housing 74 in is flat but can also be referred to as the upper housing. The lower housing 70 defines a top opening 71 and includes a wall generally labeled 72, which includes a bottom wall 73, a first side wall 78A and a second side wall 78B extending between the bottom wall 73 and the top opening 71, and a first end wall 79A and a second end wall 79B extending between the bottom wall 73 and the top opening 71. As described above, the embodiments are not limited to a specific number of batteries, a specific battery chemistry or type, or a specific interconnection configuration.

[0032] To minimize particulate and non-particulate (e.g., vapor) contamination of the battery and interconnects, the lower housing 70 and / or the upper housing 74 are each made of one or more materials that are impervious to water and water vapor and preferably made of materials that are generally impervious to other liquids and gases. Additionally, since the housing members (e.g., the lower housing 70 and the upper housing 74) are intended to house multiple cells, in some cases hundreds or thousands of cells, the housing members can be made of materials capable of withstanding the weight of the cells to meet the intended application. For example, the material for one or both of the housing members can include metals (e.g., aluminum, aluminum alloys, steel, etc.) or plastics or high-strength lightweight composite materials (e.g., carbon composites). In some cases, it may be necessary to coat the material forming the housing with a water-impervious layer, such as depositing a metal layer on a plastic housing structure. A variety of well-known coating techniques (e.g., vapor deposition) can be used to add such a water-impervious layer. The material used for the housing components can be selected based on the mechanical and electrical properties of the material (e.g., high strength, low weight, high structural stiffness, non-conductive, etc.) rather than based on liquid and gas impermeability.

[0033] To achieve the desired impermeability of the package, a compressible and impermeable seal or gasket 107 (which can be an elastomer) is inserted between the complementary mating surfaces of the lower housing member 70 and the upper housing member 74. Those skilled in the art will recognize that there are numerous materials that can be used to manufacture the gasket 107, exemplary materials including but not limited to polyurethane, polychloroprene, rubber edge composites, coated (e.g., PVC-coated) polymers, uncoated polymers, synthetic rubbers (e.g., butyl rubber), and acrylic-impregnated polyurethane.

[0034] In the exemplary battery pack 11, the gasket 107 is positioned between the flange 109 of the lower housing member 70 and the surface of the flat upper housing member 74. In a configuration using a non-flat upper housing member ( Figures 4 to 6 ), the upper housing member can include a flange complementary to the flange 109. The gasket 107 can be flat as shown or use an alternative configuration (e.g., circular cross-section before compression). The battery pack 11 can include devices such as a plurality of bolts 111 for compressing the gasket 107 and holding the housing members together. The bolts 111 can also be used to attach the package 60 to an installation structure for the intended application, such as connecting to an installation bay of an electric vehicle.

[0035] To protect the battery 18 from environmentally induced performance degradation, all connections to the interior volume of the enclosure 60 can be hermetically sealed. Thus, in the exemplary battery pack 11, the electrical connection (or electronic feedthrough port) 113 is hermetically sealed to the lower housing member 70, and the coolant ports 115A, 115B that connect to the coolant inlet line 117A and the coolant outlet line 117B for coupling an active cooling system to the battery pack are also hermetically sealed.

[0036] Although various different techniques can be used to collect and remove water vapor in the battery pack, a desiccant can also be used to remove water vapor within the enclosure 60 via absorption and / or adsorption. In the battery pack 11, the desiccant is held within a container 117 mounted within the enclosure. The battery pack can also include a pressure management system that ensures that the pressure differential between the interior volume of the enclosure and the external environment remains within a predetermined range. In the battery pack 11, a pressure management system is included, and the pressure management system can have one or more pressure relief valves 119. The one or more pressure relief valves 119 ensure that the pressure differential between the interior enclosure volume and the external environment does not become so large as to cause damage to the enclosure structure. The pressure differential can be caused by the battery pack moving to a different altitude and thus being subject to different external pressures, or it can be caused by component venting, cell ventilation, temperature changes, etc. To maximize the reduction of the risk of water vapor entering the enclosure via the pressure relief valve, the valve is provided with a preset pressure relief point (i.e., set point). The pressure relief set point can vary depending on the release direction, i.e., inward release or outward release, or the same set point can be used. A typical pressure relief set point is 1 psi in either direction.

[0037] Figure 8 A heat transfer system 160 is shown that can be inserted into the lower housing 70 and can be used as a supplement or alternative to the coolant channels described above. The system 160 can employ heat pipes 170, which, in one embodiment, have an L-shape as shown. The evaporation surface 180 can be oriented substantially horizontally (e.g., inside a battery pack of an electric vehicle), while the condensation surface 190 can be oriented substantially vertically. The battery cells 18 (e.g., 18650-type lithium-ion batteries) as shown are positioned on one of the heat pipes. The interface between the battery cells and the heat pipes is achieved through thermal contact that requires a thermal interface material (TIM). For example, the heat pipes can have multiple adjacent parallel heat segments that are attached to each other (e.g., by welding). These battery cells can have more or fewer battery cells than shown in this example, and / or these battery cells can be arranged in different configurations. For clarity, Figure 9 a subset of the battery cells is shown. The energy storage system can be implemented with any number of battery cells.

[0038] Energy storage system 160 has at least one heat transfer channel 200 that exchanges heat with heat pipes 170. A coolant fluid can be supplied to system 160 as disclosed above. For example, the energy storage system described herein can be incorporated as a battery pack into an electric (or hybrid) vehicle, and then a cooling system external to the battery pack can cool the fluid from the heat transfer channel to remove heat from the battery cells.

[0039] In Figure 8 it, the heat transfer channel 200 is disposed in the middle of the energy storage system 160, and the battery cells 18 can be positioned in rows on each side of the channel, for example at position 210. The condensation ends / surfaces of the respective heat pipes are positioned such that they abut against the sides of the heat transfer channel. Thus, the heat pipes extend in opposite directions from the channel. The heat pipes 170 shown for positioning the battery cells 18 include six parallel heat pipe segments. By way of example only, each such segment can include a dozen or so independent internal channels, each of which operates independently according to the heat pipe principle.

[0040] Turning to Figure 9 According to the embodiment, additional aspects of the package 60 shown in Figure 7 are disclosed. The package 60 includes a lower housing 70 or a housing. A top opening 71, a bottom wall 73, and first side walls 78A and second side walls 78B are shown. Each of the walls 72 has an inner surface 114 such that the lower housing 70 defines a storage cavity 64 for storing the battery cells 18. In Figure 9 it, the lower housing 70 defines a U-shaped profile. The walls 72 have an outer surface 116 that defines an outer housing that is spaced apart from the inner surface 114 to define a core cavity 112A between the outer housing and the inner surface.

[0041] The lower housing 70 includes a foam core 112 located in the core cavity 112A between the inner surface 114 and the outer surface 116. The core 112 can be formed as a rigid foam. The core 112 can be formed of open-cell foam or closed-cell foam. The core 112 can be made of polyurethane foam. The core can be formed of a flame retardant material such as foam. The core can be formed of ULTEM manufactured by the applicant. The thickness of the core 112 can be between 5 mm and 15 mm.

[0042] Referring to Figure 9 and Figure 10 a coolant channel 90 facing the cavity is formed in the lining 114 and the coolant channel facing the cavity is sealed to the battery storage cavity 64. The channel 90 can be formed only in the bottom wall 73 of the package 60. In one embodiment, each lining surface 114 along each package wall 72 can define a coolant channel 90 facing the cavity. The channel 90 can have a U-shaped or V-shaped profile.

[0043] The coolant passage 90 can be covered by a passage cover 82. The passage cover 82 can be thermally conductive but non-conductive. The passage cover 82 can be metallized plastic. The coolant 110 within the coolant passage can be ethylene glycol or an ethylene glycol-water mixture.

[0044] Go to Figure 11 , the integral seamless liner 114 can be compression molded, injection molded, or thermoformed. Thermoforming includes: heating a continuous seamless plastic sheet 230 to its softening point, attaching the plastic sheet 230 to the inner surface of a mold 240 shaped as a battery storage cavity 64 via vacuum suction, using vacuum suction through a vacuum suction port 250 in the mold 240 to form the storage cavity 64 and, for example, the coolant passage 90, and cooling the plastic sheet 230. A similar process is also applied to manufacturing a refrigerator cabinet. The liner 114 can be formed from a polymer. The liner 114 can be formed from a thermoset or thermoset composite. The liner 114 can be made of flame-retardant polypropylene. The liner 114 can be flame-retardant polycarbonate. The liner can be formed from LEXAN manufactured by the applicant. The liner can be made of expanded plastic or have an expanded coating. The liner 114 can be a material capable of withstanding direct exposure to flame, i.e., a flame-retardant material, preferably having a UL94 V0 rating at the minimum thickness of the liner. The liner can be made of a material with a glass fiber content between 20% and 30% or higher. The thickness of the liner 114 can be between 1 mm and 4 mm.

[0045] Return to Figure 9 , the outer housing 116 can be inductive for charging the battery cells 18 within the package 60. The outer housing 116 can also be configured as a ground plane. The outer housing 116 can be configured to allow radio frequency signals to pass through and can be configured to attenuate electromagnetic interference (EMI). The outer housing 116 can be formed from a metal cladding, which can be ferromagnetic. The outer housing 116 alternatively can be made of metallized plastic. The outer housing 116 can be formed from copper, nickel, aluminum, or steel. The thickness of the outer housing 116 can be less than 10 mm, more specifically, the thickness can be between 0.2 mm and 2.9 mm.

[0046] An outer layer of metallized plastic (typically 260) can be disposed within the core 112 and serve as layer 260A against the outer housing 116 or as layer 260B against the liner 114.

[0047] The outer housing 116 or the lining 114 can be formed as an ABA sandwich composite structure. The lining 114 can be a sandwich structure with a metal substrate, where layer 114A faces the core 112, layer 114B faces outward (e.g., towards the storage cavity 64 for the lining 114, or towards the outside of the package 60 for the outer housing 116), and the metallized plastic layer 114C is located between layer 114A and layer 114B. In one embodiment, the package 60 can be corrosion-resistant and fire-resistant.

[0048] The upper cover 74 (or lid or cover) can be releasably connected to the package 60 at the cover opening 71. The upper cover 74 and the lower cover 70 together can define the package 60. The upper cover 74 can be sealed to the lower cover 70 via a gasket 107.

[0049] The outer housing 116 can include isolation ports 275, which include a core filling port 275A and an exhaust port 275B. Foam can be dispensed into the core cavity 112A via the filling port 275A, and any air therein can be discharged through the exhaust port 275B. After filling the core cavity 112A with the core material 112, plugs 277A, 277B can be inserted into the core filling port 275A and the exhaust port 275B. After filling the core material 112, the core 112 can be vacuum-sealed. The foam 112 between the lining 114 and the outer cladding 116 can be a flame-retardant foam or an inherently flame-retardant foam, such as silicone foam.

[0050] The lower cover 70 can define coolant ports, which include a coolant inlet port 115A and a coolant outlet port 115B. The coolant 110 can be delivered from these ports 115A, 115B through the coolant channels 90.

[0051] The core 112 can be formed with a core support member 270, which can extend within the core cavity 112A between the outer housing 116 and the lining 114. The support member 270 can be configured to prevent buckling between the outer housing 116 and the lining 114. The core support member 270 can be one or more ribs. The lining 114 can be formed with a lining support device 280, which can be a support indentation 280A or a protrusion 280B. The lining support device 280 can be honeycomb-shaped or can be composed of one or more ribs.

[0052] In one embodiment, the cooling tubes and tube arrays 285 (some of which are Figure 9As shown (in [figure reference]), it can be used for cooling and, for example, be located below the liner 114 along any one or more of the walls 72. For simplicity, the cooling tube array 285 is shown as being located below the liner 114 along the side wall 78, but this is not intended to limit the scope of the embodiments. A condenser-evaporator cooling system schematically shown at 287 can be employed. For example, thermoelectric cooling, heat pipes, and immersion cooling systems can be integrated into the liner / metal cladding sandwich structure. For simplicity, a cooling system 287 is also schematically shown as being located below the liner 114 along the side wall 78A, but this is not intended to limit the scope of the embodiments.

[0053] Data related to, for example, the health of battery cells can be transmitted through the encapsulation 60. An on-vehicle processor in the vehicle 5 can receive the transmitted data, and the data can be displayed on an instrument panel information display or other displays (such as a smartphone). The electronic port 113 can be formed through the lower housing 70. For example, this can be used to transmit power from the battery to vehicle components that require power, such as a drive motor.

[0054] In summary, these embodiments employ techniques for thermoforming or injection molding the liner and polyurethane foam to manufacture the liner of the battery encapsulation. These embodiments can be scaled up to produce millions of units per year. In essence, these embodiments provide a sandwich structure having an external metal cladding (steel or aluminum), a honeycomb or foamed or rigid foam core, and a flame-retardant or expandable plastic (PP or PC) inner liner. The liner can be a material capable of withstanding direct exposure to fire, i.e., a flame-retardant material, preferably achieving a UL94 V0 rating at the minimum thickness of the liner. The foam between the liner and the outer cladding can be a flame-retardant foam or an inherently flame-retardant foam, such as silicone foam. The thickness of each foam can be a few millimeters. In one embodiment, the sandwich structure can be formed as the lower and upper parts of the encapsulation that houses one or more battery cells and forms a battery box. The embodiments provide an encapsulation configured for fire protection that thermally isolates and electrically isolates internal components such as battery cells for low-frequency EMI protection and electrical grounding of the encapsulation. The embodiments utilize copper, aluminum, or steel as the outer cladding, achieve electroplated encapsulation through a cover, and allow sealing of the periphery by using an elastomeric seal. The disclosed liner is a thin thermoformed or injection molded or compression molded shell that exhibits an expansion behavior, such as by using an extrudable FR STAMAX TM or FR PPc, where the glass fiber content is 20% to 30% to obtain higher rigidity. The liner can include flow channels that can be closed with an aluminum plate at the top.

[0055] Turning to Figure 12, The process flow diagram shows a method for manufacturing the package 60. The order of the method steps provided herein is not intended to limit the scope of the embodiments. As shown in block 1010, the method includes forming the lower housing 70. As shown, the lower housing 70 has a bottom wall 73, a first side wall 78A and a second side wall 78B (collectively referred to as side walls 78) that extend upward from the bottom wall to the top end 70T of the lower housing 70, and a first end wall 79A and a second end wall 79B (collectively referred to as end walls 79) that extend upward from the bottom wall 73 to the top end 70T. The top end 70T defines a housing opening. Each of the housing walls has an inner surface 114 such that the housing defines a storage cavity 64 for storing the battery cells 18. Each of the walls also includes an outer surface 116. The inner surface and the outer surface are spaced apart from each other to define a core cavity 112A.

[0056] Other aspects of forming the housing (block 1010) are disclosed in blocks 1010A to 1010G. As shown in block 1010A, the method includes forming an integral seamless lining 114. As shown, the lining defines the inner surface of each of the housing walls and forms the battery storage cavity 64. The lining 114 also defines a storage cavity facing the coolant channel 90, which is fluid-sealed with the battery storage cavity 64 and may have a U-shaped or V-shaped profile. The coolant channel 90 is formed in one or more of the inner surfaces 114. The lining is formed in one of the following ways: compression molding; injection molding; or thermoforming. Thermoforming includes: heating a continuous seamless plastic sheet, attaching the plastic sheet to the inner surface of a mold formed as the battery storage cavity via vacuum suction, and cooling the plastic sheet.

[0057] The lining 114 may be a polymer. Alternatively, the lining may be a thermosetting or thermosetting composite material. Alternatively, the lining may be flame-retardant polypropylene. Alternatively, the lining may be flame-retardant polycarbonate. Alternatively, the lining may be made of LEXAN. Alternatively, the lining may be an expandable plastic or have an expandable coating. Alternatively, the glass fiber content of the lining may be between 20% and 30% or higher. The lining 114 may be a material capable of withstanding direct exposure to flames, i.e., a flame-retardant material, preferably having a UL94 V0 rating at the minimum thickness of the lining. In one embodiment, the thickness of the lining may be between 1 mm and 4 mm. In another embodiment, the lining 114 is combined with an expandable material to limit the spread of fire in the event of battery thermal runaway, and a flame-retardant material or an inherently flame-retardant foam (such as silicone foam) is located between the lining 114 and the outer cladding 116.

[0058] One or more sockets 155 configured to receive the battery cells 18 may be formed in the lining 114. The sockets 155 may be formed by the coolant channel 90.

[0059] As shown in block 1010A1, forming the liner includes forming structural support indentations or protrusions 280A, 280B integral with the liner. As shown, the structural support indentations or protrusions 280A, 280B of the liner 114 can be one or more ribs.

[0060] As shown in block 1010B, the method includes providing an outer housing 116. As shown, the outer housing defines the outer surface of each of the cover walls and can be one or more of the following: inductive for charging battery cells within the package; and configured for radio frequency signal transmission therethrough. The outer housing 116 or the liner 114 can be formed as an ABA sandwich composite structure. For example, the liner 114 can be a metal sandwich structure having a core-facing layer and an outer-facing layer and a metallized plastic layer therebetween. Alternatively, the metallized plastic 260A or 260B layer can be located within the core cavity 112A, against the outer housing 116 or the liner 114.

[0061] The outer housing 116 can be a ground plane. Alternatively, the outer housing can be configured to attenuate electromagnetic interference (EMI). Alternatively, the outer housing can be formed of a metal cladding, and the metal cladding can be ferromagnetic. Alternatively, the outer housing can be a metallized plastic. Alternatively, the outer housing can be copper, nickel, aluminum, or steel. In one embodiment, the thickness of the outer housing can be less than 10 mm, or more specifically, the thickness can be between 0.2 mm and 2.9 mm.

[0062] As shown in block 1010B1, within the core cavity 112A, cooling tubes and tube arrays 285 and / or a condenser-evaporator cooling system as a cooling system 287 can be mounted along one or more of the cover walls 72 for cooling the battery cells 18. As shown in block 1010C, the method includes filling the core cavity 112A with foam. Additional aspects of filling the core cavity (block 1010C) are disclosed in blocks 1010C1 through 1010C3. As shown in block 1010C1, the method includes forming a fill port 275A and an exhaust port 275B in the outer housing 116. As shown in block 1010C2, the method includes filling the core cavity 112A with foam via the fill port 275A while gas within the core cavity exits through the exhaust port 275B. As shown in block 1010C3, the method includes inserting plugs 277A, 277B into the exhaust port and the core fill port after filling the core cavity with foam.

[0063] The core 112 can be a rigid foam. Alternatively, the core can be an open-cell foam or a closed-cell foam. Alternatively, the core can be a polyurethane foam. Alternatively, the core can be flame-retardant. Alternatively, the core can be made of ULTEM. In one embodiment, the thickness of the core can be between 5 mm and 15 mm. In one embodiment, the core can be vacuum-sealed.

[0064] As shown in block 1010D, forming the lower housing 70 includes forming a coolant inlet port 115A and a coolant outlet port 115B through the housing. With this configuration, coolant 110 can be conveyed through coolant channels 90. As shown in block 1010E, the method includes covering the coolant channels 90 with a channel cover 82. The channel cover 82 can be thermally conductive but non-conductive. Alternatively, the channel cover 82 can be a metallized plastic.

[0065] As shown in block 1010F, the method includes forming an electronic feedthrough port 113 through the housing. As shown in block 1010G, the method includes forming a structural support member 270 between the outer housing 116 and the liner 114 within the core cavity 112A. As shown, the structural support member 270 is configured to prevent buckling between the outer housing 116 and the liner 114. The structural support member 270 is one or more ribs or forms a honeycomb shape.

[0066] As shown in block 1020, the method includes releasably connecting the upper housing 74 to the housing opening. This forms the package 60. As shown in block 1020A, the method includes sealing the upper housing 74 to the housing via an elastomeric seal. As shown in block 1030, the method includes filling the coolant channels with coolant 110. The coolant can be ethylene glycol or an ethylene glycol-water mixture.

[0067] As described above, the thermoforming of the liner can be performed similarly to the thermoforming of a refrigerator cabinet. Thermoforming is a process of heating a thermoplastic sheet to its softening point. The sheet is stretched onto a single-sided mold and then manipulated. Thereafter, the sheet cools into the desired shape. Thermoforming methods include vacuum forming, pressure forming, and mechanical forming. In vacuum forming, the mold is opened, and the vacuum pressure required to form the sheet into the desired shape can be about 15 psi in some embodiments. Pressure forming adds a pressure chamber to the tooling set and utilizes both vacuum and positive air pressure. The forming pressure generated by this process is three to four times that of vacuum forming. Thus, fine details such as surface textures can be formed on the mold without incurring excessive additional costs. Vacuum forming is a type of thermoforming. However, in vacuum forming, the plastic conforms to the mold during the forming process. Vacuum forming is used for plastic parts that require the formation of cavities.

[0068] Materials that can be used for thermoforming include ABS (acrylonitrile butadiene styrene), which has good stiffness and impact strength and comes in different colors and textures. Acrylic (polymethyl methacrylate, plexiglass or PMMA) is transparent and wear-resistant and is relatively easy to manufacture, and also has impact-modified grades and comes in a variety of colors. HDPE (high-density polyethylene) has relatively good impact resistance and chemical resistance, and also has good cold resistance. HIPS (high-impact polystyrene) is a low-cost material that is relatively easy to form and is available in a variety of colors. HMPWE (high molecular weight polyethylene) has relatively high impact strength, chemical resistance and puncture resistance. KYDEX (a PMMA / PVC mixture) has relatively good chemical resistance and impact resistance, and comes in different colors and textures. LEXAN has relatively good flame retardancy and scratch resistance, and can withstand various climate conditions. PC (polycarbonate) has relatively high impact strength, is transparent and heat-resistant. Pennite (glass-filled nylon) is relatively strong, hard and inexpensive. PEI (polyetherimide, such as ULTEM) is a relatively heat-resistant material and can be pressure-heated. PETG (polyethylene terephthalate glycol) is transparent and has relatively good impact strength. PP (polypropylene) has relatively good chemical resistance, is hard and has good impact strength. PVC (polyvinyl chloride) is a rigid material with relatively high strength, good impact strength and flame retardancy. Royalite is durable, has high impact strength and high tensile strength. RPET (recycled polyethylene terephthalate glycol) is transparent and low-cost. TPO (thermoplastic polyolefin) has relatively good impact performance. Vinyl is durable, flame-retardant and is a good electrical conductor. Thermoplastics are the final products produced by thermoforming processes. The advantage of thermoplastics is that they can withstand repeated activation. For example, they can be reheated and reformed, and can be recycled. In addition, due to the chemical properties involved, thermoplastics exhibit the same characteristics as rubber and can have the same strength as aluminum. The temperature tolerance of thermoplastics varies and ranges from 100 degrees Fahrenheit (or lower) to 600 degrees Fahrenheit (or higher). Thermoplastics have good electrical insulation and thermal insulation properties, and if metals or carbon are added, thermoplastics can also conduct electricity.

[0069] It should be understood that, without departing from the scope of the present disclosure, the features of each of the embodiments described above can be combined into a single embodiment, or selected features can be utilized in one or more embodiments.

[0070] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that when the terms "comprises" and / or "comprising" are used in this specification, they specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0071] Those skilled in the art will appreciate that various example embodiments are shown and described herein, each having certain features in a particular embodiment, but the disclosure is not limited thereto. On the contrary, the disclosure may be modified to include any number of variations, alterations, substitutions, combinations, sub - combinations, or equivalent arrangements not heretofore described but commensurate with the scope of the disclosure. In addition, while various embodiments of the disclosure have been described, it should be understood that aspects of the disclosure may only include some of the described embodiments. Accordingly, the disclosure should not be regarded as limited by the foregoing description, but only by the scope of the appended claims.

Claims

1. A method of manufacturing an encapsulation (60) for encapsulating a battery in an automobile (5), the method comprising: Forming a cover body (70) having a cover body wall including a bottom wall, a first side wall and a second side wall extending upward from the bottom wall of the cover body to a top end, and a first end wall and a second end wall extending upward from the bottom wall to the top end, wherein the top end defines a cover body opening, and wherein each of the cover body walls has: an inner surface such that the cover body defines a storage cavity (64) for storing battery cells; and an outer surface, and the inner surface and the outer surface are spaced apart from each other to define a core body (112) cavity, wherein forming the cover body (70) includes: Forming a lining (114) that is an integral seamless lining defining the inner surface of each of the cover body walls (70) and thus defining the storage cavity (64), and the lining also defines a coolant passage (90) disposed adjacent to the storage cavity (64), the coolant passage being configured to be fluid-sealed with the storage cavity (64), wherein the coolant passage (90) is formed along the inner surface of one or more of the cover body walls of the cover body (70), wherein the lining (114) is formed by one of: compression molding, injection molding, or thermoforming, and wherein forming the lining (114) includes: heating a continuous seamless plastic sheet, attaching the continuous seamless plastic sheet to a mold shaped as the storage cavity (64) via vacuum adsorption, and cooling the continuous seamless plastic sheet; Providing an outer housing (116) defining the outer surface of each of the cover body walls (70), wherein the outer housing (116) is one or more of: The outer housing is inductive for charging the battery cells within the encapsulation (60); and The outer housing is configured to allow radio frequency signals to pass through; Filling the core body cavity with foam; Forming a coolant inlet port and a coolant outlet port passing through the cover body (70) and in sealed fluid communication with the coolant passage (90); and Forming an electronic feedthrough port passing through the cover body (70); and Releasably connecting a cover to the cover body opening (70) to thereby define the encapsulation (60).

2. The method according to claim 1, wherein, Filling the core body cavity with the foam includes: Forming a filling port (275A) and a vent port (275B) in the outer housing (116); Filling the core body cavity with the foam via the filling port while forcing the gas within the core body cavity to discharge from the vent port; and After filling the core body cavity with the foam, inserting plugs (277A, 277B) into the filling port and the vent port.

3. The method according to claim 1 or 2, the method comprising installing cooling tubes (285) and tube arrays (285) and / or a condenser-evaporator cooling system along one or more of the cover body walls within the core body cavity for cooling the battery cells.

4. The method according to any one of the preceding claims, wherein, Forming the housing (70) further includes forming a support member (270) in the core cavity, between the outer housing and the lining, to prevent buckling between the outer housing and the lining, and optionally wherein the structural support member is one or more ribs or forms a honeycomb shape; and optionally wherein forming the lining further includes forming structural support indentations or protrusions integral with the lining.

5. The method according to any one of the preceding claims, wherein, The outer housing (116) or the lining (114) is formed as an ABA sandwich composite structure, and optionally wherein the lining is a metal sandwich structure having a core-facing layer, an outer-facing layer, and a metallized plastic layer therebetween.

6. The method according to any one of the preceding claims, wherein, The outer housing (116) is a ground plane and is optionally configured to attenuate electromagnetic interference (EMI), and optionally wherein the outer housing (116) is formed of a metal cladding, and optionally wherein the metal cladding is ferromagnetic, and optionally wherein the outer housing (116) is metallized plastic (260A, 260B), and optionally copper, nickel, aluminum, or steel, optionally the thickness of the outer housing (116) is less than 10 mm, optionally wherein the thickness of the outer housing (116) is between 0.2 mm and 2.9 mm.

7. The method according to any one of the preceding claims, wherein The metallized plastic layer is located within the core cavity, against the outer housing (116) or the lining; and optionally wherein the method includes sealing the lid to the housing via an elastomeric seal.

8. The method according to any one of the preceding claims, wherein, Each of the coolant channels (90) defines a U-shaped profile or a V-shaped profile.

9. The method according to any one of the preceding claims, wherein Forming the housing includes covering the coolant channels with a channel cover (82), and optionally wherein the channel cover (82) is thermally conductive but not electrically conductive, and optionally wherein the channel cover (82) is formed of metallized plastic.

10. The method according to any one of the preceding claims, the method including filling the coolant channels with a coolant, and optionally wherein the coolant is ethylene glycol or an ethylene glycol-water mixture.

11. The method according to any one of the preceding claims, wherein, The encapsulation is electroplated, and optionally wherein the encapsulation is fireproof.

12. The method according to any one of the preceding claims, wherein, The lining is a polymer, and optionally wherein the lining is a thermosetting material or a thermosetting composite material, and optionally wherein the lining is flame-retardant polypropylene, and optionally wherein the lining is flame-retardant polycarbonate, and optionally wherein the lining is formed of polycarbonate, and optionally wherein the lining includes an expanded plastic or has an expanded coating, and optionally wherein the glass fiber content of the lining is between 20% and 30% or higher, and optionally wherein the thickness of the lining is between 1 mm and 4 mm.

13. The method according to any one of the preceding claims, wherein, The core cavity is filled with a rigid foam, optionally wherein the core cavity is filled with an open-cell foam or a closed-cell foam, optionally wherein the core cavity is filled with a polyurethane foam, optionally wherein the core cavity is filled with a flame-retardant material, optionally wherein the core cavity is filled with a polyetherimide, optionally wherein the thickness of the core cavity is between 5 mm and 15 mm, optionally wherein the core cavity is vacuum-sealed.

14. An encapsulation formed by the method according to any one of the preceding claims, the battery cell being included in the encapsulation.

15. A motor vehicle, the motor vehicle including a controller and an encapsulation according to any one of the preceding claims, the controller being configured to determine a remaining charge within the battery cell in the encapsulation and provide an indication of the remaining charge within the battery cell on an information reader.

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