Systems and methods for thermal management and dimensional control of battery assemblies

Abstract

Systems and methods for thermal management and dimensional control of battery assemblies are provided. Systems and methods for thermal management and dimensional control of battery systems include forming straps for removing heat from the battery system. Battery cells are assembled into ranks, where each rank is disposed between two of the straps. Prior to assembling the battery cells into ranks, subassemblies are formed, each subassembly including one of the straps and one of the ranks of battery cells in a pre-bonded cell rank. The battery cells of each subassembly are secured to one of the straps by a first thermal interface material. After the battery cells of each subassembly are secured to their respective one of the straps as one of the pre-bonded cell ranks, multiple subassemblies are stacked. The battery cells of each subassembly are secured to the straps of another subassembly by a second thermal interface material to form a battery module.

Description

Technical Field

[0001] The technology field generally relates to batteries, and more specifically to battery modules and battery assembly methods using cell stacking technology, which provides improved thermal management and geometric precision for applications such as electric vehicles. Background Technology

[0002] A battery assembly may include multiple individual cells assembled together in a tightly packed form, such as in a battery pack. The cells may include any of several types of compositions for energy storage, such as lithium-ion. The battery cells may be electrically connected in parallel or series to deliver power to a power-consuming device in an application and for recharging. Each battery cell includes one or more electrodes. In some embodiments, the electrode pair of each cell may include a negative electrode (anode) and a positive electrode (cathode).

[0003] In various applications, numerous battery cells can be clustered close together and assembled into a rechargeable energy storage system (RESS). When batteries are packaged together, thermal management may be required, necessitating the inclusion of devices for cooling and / or heating. Assembling battery systems presents several challenges, including providing components that operate efficiently and are thermally controlled, while maintaining desired levels of tolerance variation in the positioning of individual cells and the assembly of components. Maintaining acceptable geometric dimensions and tolerances is desired for various reasons, including to achieve proper electrical connections.

[0004] Therefore, it has been desirable to provide battery assemblies that achieve desired operational and manufacturing effectiveness and efficiency while controlling size and providing a compact form. Efficient thermal management is also desirable. Furthermore, other desirable features and characteristics of this disclosure will become apparent from the accompanying drawings and the foregoing introduction, based on the following detailed description and the appended claims. Summary of the Invention

[0005] In several embodiments, a method for thermal management and dimensional control of a battery system includes forming strips for removing heat from the battery system. Battery cells are assembled into rows, with each row disposed between two strips in the strips. Before assembling the battery cells into rows, sub-assemblies are formed, each sub-assembly including one strip from the strips and one row of battery cells from the battery cell rows in a pre-bonded cell row. The battery cells of each sub-assembly are secured to one strip from the strips using a first thermal interface material. After the battery cells of each sub-assembly are secured to their respective strips to become one of the pre-bonded cell rows, multiple sub-assemblies are stacked. The battery cells of each sub-assembly are secured to the strips of another sub-assembly using a second thermal interface material to form a battery module.

[0006] In an additional embodiment, the first thermal interface material is a first material having a first viscosity. The second thermal interface material is a second material having a second viscosity, the magnitude of which is substantially higher than the first viscosity.

[0007] In an additional embodiment, an acrylic resin is selected as the first thermal interface material, and one or more of silicone, polyurethane, and epoxy resins are selected as the second thermal interface material.

[0008] In an additional embodiment, a first gap is provided between each battery cell and its corresponding strip. A second gap is provided between each battery cell and a strip belonging to an adjacent pre-bonded cell array within the strip. The first gap is set to be substantially smaller than the second gap.

[0009] In an additional embodiment, the battery cells of the respective sub-assemblies are held in place relative to each other by tools before forming the pre-bonded cell array.

[0010] In an additional embodiment, when the pre-bonded cell array is formed to the following closure height (H), the closure tool is: H = Rt + t + Cd + ΔT, where Rt is the thickness of the strip, t is the gap between the battery cell and the strip, Cd is the diameter of the battery cell, and ΔT is the tolerance variation factor of the strip, the battery cell, and the tool.

[0011] In an additional embodiment, each of the battery cells in the battery module is coupled to two strips in a strip to provide double-sided cooling for each of the battery cells.

[0012] In an additional embodiment, the battery module is coupled into a thermal management system that operates to circulate coolant through each of the strips in the battery module.

[0013] In an additional embodiment, each battery cell is formed in a cylindrical shape, and the strip is formed in a serpentine shape.

[0014] In an additional embodiment, a first gap is provided between each battery cell and a corresponding strip in its corresponding pre-bonded cell row. A second gap is provided between the cell and a strip belonging to an adjacent pre-bonded cell row. The selection of the first and second gaps achieves dimensional positioning and provides a cooling effect.

[0015] In several additional embodiments, a system for thermal management and dimensional control of a battery system includes strips operable to remove heat from the battery system. Battery cells are arranged in rows, with each row disposed between two strips in the strip. Sub-assemblies are formed, each sub-assembly including one strip from the strip and one row of battery cells from the battery cell rows in a pre-bonded cell row. The battery cells of each sub-assembly are secured to one strip from the strip via a first thermal interface material. After the battery cells of each sub-assembly are secured to their respective strip as one of the pre-bonded cell rows, multiple sub-assemblies are configured to be stacked and secured via a second thermal interface material to form a battery module.

[0016] In an additional embodiment, the first thermal interface material is a first material having a first viscosity, and the second thermal interface material is a second material having a second viscosity, the magnitude of which is substantially higher than that of the first viscosity.

[0017] In an additional embodiment, the first thermal interface material is an acrylic resin, and the second thermal interface material is at least one of silicone, polyurethane, and epoxy resin.

[0018] In an additional embodiment, each battery cell has a first gap with its corresponding strip and a second gap with a strip belonging to an adjacent pre-bonded cell array within the strip. The first gap is set to be substantially smaller than the second gap.

[0019] In an additional embodiment, the tool operates to hold the battery cells of the respective sub-assemblies in place relative to each other before forming a pre-bonded cell array.

[0020] In an additional embodiment, the tooling operation is closed when the pre-bonded cell array is formed to the following closed height (H): H = Rt + t + Cd + ΔT, where Rt is the thickness of the strip, t is the gap between the battery cell and the strip, Cd is the diameter of the battery cell, and ΔT is the tolerance variation factor of the strip, the battery cell, and the tooling.

[0021] In an additional embodiment, each of the battery cells in the battery module is bonded to two strips in a strip to provide double-sided cooling for each of the battery cells.

[0022] In an additional embodiment, the thermal management system operates to circulate coolant through each of the strips in the battery module.

[0023] In an additional embodiment, each battery cell has a first gap with a corresponding strip in its corresponding pre-bonded cell row, and a second gap with a strip belonging to an adjacent pre-bonded cell row. The first and second gaps are selected and controlled for dimensional positioning and cooling effect.

[0024] In several other embodiments, a method includes forming strips for circulating fluid for thermal management of a battery system. Battery cells are assembled into rows to form sub-assemblies, each sub-assembly including a strip from the strips and a row of battery cells from the rows of cells as a spring strip. The spring strip includes battery cells bonded to a strip from the strips. Within each spring strip, the battery cells are spaced apart from each other and all located on the same side of a strip from the strips. In a tool for holding the battery cells of the respective sub-assemblies in place relative to each other, the battery cells of each sub-assembly are secured to a strip from the strips by a first thermal interface material. The first thermal interface material is disposed in the tool. After the battery cells of each sub-assembly are secured to their respective strips as one of the pre-bonded cell rows, multiple sub-assemblies are stacked. The battery cells of each sub-assembly are secured to a strip from another sub-assembly by a second thermal interface material to form a battery module. The battery cells are assembled into rows, wherein each row in the rows is disposed between two strips from the strips. Attached Figure Description

[0025] Exemplary embodiments will now be described in conjunction with the following figures, wherein the same numerals denote the same elements, and wherein:

[0026] Figure 1 This is a functional block diagram of a vehicle including a battery cell system according to various embodiments;

[0027] Figure 2 According to various embodiments Figure 1 A schematic top view of the vehicle's battery module;

[0028] Figure 3 According to various embodiments Figure 2 A detailed view of a portion of the battery module;

[0029] Figure 4a This is a schematic diagram of the welding area on a battery cell according to various embodiments;

[0030] Figure 4b This is a schematic diagram of a battery cell undergoing welding operation according to various embodiments;

[0031] Figure 5 According to various embodiments, it is used for Figure 2Battery module with spring belt cell system and Figure 1 A flowchart of the vehicle's process;

[0032] Figure 6 This is a schematic diagram of forming cooling strips in a tool according to various embodiments;

[0033] Figure 7 This is a schematic diagram of cooling strips formed in a tool according to various embodiments;

[0034] Figure 8 These are schematic diagrams of strip and manifold assemblies according to various embodiments;

[0035] Figure 9 This is a schematic diagram illustrating the application of bonding material to the spring band according to various embodiments;

[0036] Figure 10 This is a schematic diagram of a tool for holding the battery cell and strip according to various embodiments;

[0037] Figure 11 It is in a closed state according to various embodiments. Figure 10 A detailed view of the tools;

[0038] Figure 12 This is a schematic diagram illustrating the application of material to a spring belt according to various embodiments;

[0039] Figure 13 This is a schematic diagram of the joining of two elastic bands according to various embodiments;

[0040] Figure 14 Based on various embodiments and Figure 2 A schematic diagram showing the spacing between adjacent cells in a battery module;

[0041] Figure 15 These are schematic diagrams of prism-shaped battery packs according to various embodiments; and

[0042] Figure 16 This is a schematic diagram of a pouch battery cartridge according to various embodiments. Detailed Implementation

[0043] The following detailed description is merely exemplary in nature and is not intended to limit application and use. Furthermore, it is not intended to be bound by any express or implied theory presented in the foregoing introduction or the following detailed description.

[0044] In various embodiments, multi-surface (e.g., dual-sided) wide-face cooling provides high-performance thermal management in battery packs, such as those used in electric vehicles. Cells can be assembled into assemblies or sub-assemblies, where they are linked together, such as in spring strips, and subsequently combined into larger cells / modules and / or complete battery packs. Multiple battery cells can be secured to cooling / heating structures (strips or cooling strips) to maintain their positional relationship. Such sub-assemblies of battery cells and strips can be referred to as pre-bonded cell rows or spring strips, regardless of their shape. For example, a single cell can be cylindrical, prismatic, pouch, or another shape, and the strip can be wavy / corrugated, flat, slotted, cavity-shaped, or other shapes. After forming the cell and strip sub-assemblies, multiple sub-assemblies / spring strips are combined to form a larger module or battery pack composed of individual cells linked in rows between strips. One tolerance management approach achieves direct control over cell position during assembly by breaking the assembly process into modular steps. As described in this article, this method offers several advantages in various aspects.

[0045] refer to Figure 1 The application of the system, also known as the elastic band cell system 20, is shown in vehicle 22. While the elastic band cell system 20 may be described in an embodiment of vehicle 22, it is not limited to that embodiment but can be applied to a variety of applications, including in any environment requiring tolerance control of battery placement and / or effective thermal management. As mentioned above, the system / elastic band cell system 20 described herein can be applied to battery cells of any shape, size, and chemistry / format.

[0046] As shown in the figure, according to an exemplary embodiment, vehicle 22 includes a RESS 40, which includes a spring-loaded battery system 20. Vehicle 22 includes a control method for initiating cooling and / or heating via the spring-loaded battery system 20. This control may be responsive to characteristics, such as the characteristics of the heat generated by RESS 40, or responsive to characteristics associated with low temperatures. In various embodiments, vehicle 22 typically includes a body 24, four wheels 26, a powertrain 28, a control system 30, and RESS 40. Body 24 substantially surrounds the other components of vehicle 22. Each wheel 26 is rotatably coupled to body 24 near a respective corner. In some embodiments, control system 30 may be multiple integrated systems.

[0047] Vehicle 22 can be any of a variety of different types of automobiles, such as, for example, a sedan, van, truck, or sport utility vehicle (SUV), and can be two-wheel drive (2WD) (i.e., rear-wheel drive or front-wheel drive), four-wheel drive (4WD), or all-wheel drive (AWD). Vehicle 22 can also incorporate any or a combination of a variety of different types of electric propulsion systems, such as a combustion / electric motor hybrid engine and a battery electric vehicle.

[0048] In an exemplary embodiment, vehicle 22 is an electric vehicle and generally includes controller 38, the aforementioned RESS 40, control system 30, powertrain 28, and power electronics 34. Powertrain 28 embodies an electric propulsion system that drives wheels 26. More specifically, the powertrain includes an electric motor 48. As those skilled in the art will understand, the electric motor 48 is associated as an integral or separate component with gear train 49 or transmission, and although not shown, it also includes a stator assembly (including conductive coils), a rotor assembly (including a ferromagnetic core), and cooling fluid or coolant. Power electronics 34 may include electric vehicle components such as power inverter module 35, accessory power module 37, and on-board charger module 39.

[0049] RESS 40 is mounted on body 24 and electrically connected to power electronics 34. In the current embodiment, RESS 40 includes at least one rechargeable battery pack with battery cells in the elastic band cell system 20 and is equipped with thermal management. In this embodiment, the cells of RESS 40 may be cylindrical cells, prismatic cells, pouch cells, or another type. RESS 40 and powertrain 28 together constitute a drive system to propel vehicle 22. RESS 40 is thermally regulated, including being thermally cooled and / or heated by the elastic band cell system 20.

[0050] Vehicle 22 includes a thermal regulation system 41 for cooling RESS 40. In other embodiments, the thermal regulation system 41 can heat up RESS 40. Typically, the thermal regulation system 41 includes a pump 52 and a sensor array 54, and can be controlled by a control system 30. In several embodiments, the thermal regulation system 41 includes a valve array 57 for controlling fluid flow, and in some embodiments may include a cooler. The thermal regulation system 41 thermally regulates RESS 40. Specifically, the thermal regulation system 41 may, as appropriate, utilize heating and cooling techniques to heat or cool RESS 40 based on instructions provided by a controller 38 (such as by a processor 62). Heating and cooling techniques are selected to achieve a desired temperature for RESS 40 while optimizing energy efficiency. The sensor array 54 may include temperature sensors and / or various status sensors, as well as other additional sensors.

[0051] Typically, controller 38 is configured to receive inputs from various sensors configured to generate signals based on various physical input parameters associated with: powertrain 28; HVAC system 32; RESS 40; and their subsystems and other related systems. In the depicted embodiment, controller 38 includes and is coupled to processor 62 and memory device 64. During operation, processor 62 executes one or more programs 44 and can use data 50, which may each be contained within storage device 68.

[0052] In the context of vehicle 22, thermal regulation system 41, including belt-driven battery system 20, cools and / or heats RESS 40 by circulating at least one working fluid. (Reference) Figure 2 A portion of the RESS 40, having the spring-loaded cell system 20, is schematically shown and referred to as module 80. The cell 70 in this embodiment is a cylindrical cell. Any available format and size of cell 70 can be used. Typically, cells 70 are electrically coupled together (not shown) and electrically coupled to other components to supply power and for recharging. The chemistry of cell 70 can be lithium-ion or any other available chemistry or type. For packaging purposes, cells 70 are typically arranged in rows 71-78 offset from each other. The number of cells 70 in each of rows 71-78 is selected according to the parameters of the application.

[0053] Cell 70 features double-sided cooling, meaning that cooling / heating structures (strips) are positioned on both sides of each cell 70. The use of double-sided or double-sided strip cooling can exacerbate challenges in geometry and tolerance setting, as discussed below. Figure 3 Further described. In an embodiment, any number of cells 70 can be assembled together using any number of strips to form a module or battery pack. In this embodiment, each cell 70 is cylindrical in shape and each strip is serpentine (wavy) in shape.

[0054] exist Figure 2In the example, a corresponding thermal management strip 81-89 is provided on each side of rows 71-78. Specifically, thermal management strip 81 is provided on the side 91 of row 71. Thermal management strip 82 is provided between rows 71 and 72. A thermal management strip 83 is provided between rows 72 and 73. Another thermal management strip 84 is provided between rows 73 and 74. Another thermal management strip 85 is provided between rows 74 and 75. Another thermal management strip 86 is provided between rows 75 and 76. Another thermal management strip 87 is provided between rows 76 and 77. Another thermal management strip 88 is provided between rows 77 and 78. Another thermal management strip 89 is provided on the side 92 of row 78. In applications, additional or fewer thermal management strips may be used. Each thermal management strip 81-89 includes a coolant inlet 94 and a coolant outlet 96. Coolant 98 can be circulated through strips 81-89 for cooling and / or heating.

[0055] Strips 81-89 are connected to manifold 93, which is connected to or is part of the thermal conditioning system 41. Manifold 93 guides fluid in and out of strips 81-89 for exchange. Manifold 93 includes ports 95 that need to be aligned with strips 81-89. In an embodiment, a separate supply manifold and return manifold may be provided on each side of module 80. During thermal conditioning, fluid circulates through strips 81-89 to move the exchanged heat.

[0056] refer to Figure 3 The position of each cell 70 within the module 80 is ideally controlled to avoid tolerance overlap, which could cause cell 70 to deviate from and / or interfere with the positions of adjacent strips (e.g., 83, 84). When cell 70 and strips 81-89 are assembled together, overlap can accumulate between the position of cell 70, the profile of strips 81-89, and the position of strips 81-89. For example, variations within allowable tolerances could cause cell 70a to be positioned with interference from strip 83 at region 97 and / or with excessive gap from strip 84 at region 99. Interference could undesirably cause strip deformation or displacement. Excessive gap could undesirably reduce heat transfer. To avoid interference and excessive gap, the spring-loaded cell system 20 provides gap control.

[0057] Besides interference and excessively large gaps, Figure 4a and Figure 4bThe advantages of controlling the position of the cell 70 for electrical connection purposes are also shown. During the assembly of module 80, cell interconnection can be performed and / or interconnect boards (ICBs) can be assembled in module 80 to achieve electrical connections at the cover 102 of the housing 104 of the cell 70. For example, some connections can be made at the solder area 106 of the protruding rivet 108 surrounding the center of the cover 102. In this example, as... Figure 4a As shown, weld area 106 is spaced apart from the center point 110 of the protruding rivet 108 and from the edge 112 of the protruding rivet 108, and is defined with tolerance limits. Another weld area 114 is spaced apart from the protruding rivet 108 in an outward direction and from the edge 116 of the housing 104, and is defined with tolerance limits. Figure 4b As shown, welding can be performed by machine 120, which in this case has at least one actuator for delivering welding energy; in this example, the actuator is electrodes 122 and 124. In embodiments, machine 120 may employ resistance, laser, ultrasonic, pulsed arc, or other joining methods. Figure 4b The welding of the positive terminal connection is shown, and the welding of the negative terminal connection can be done similarly. For the weld to be within the tolerance limits of weld zones 106 and 114, the cell 70 must be correctly positioned within the module 80. Accordingly, the spring-loaded cell system 20 provides this positioning.

[0058] refer to Figure 5 The method 200 using the spring-loaded battery cell system 20 is illustrated in flowchart form. As will be understood from this disclosure, the order of operations within method 200 is not limited to... Figure 5 The steps shown are performed sequentially, but may be performed in one or more different orders as applicable and in accordance with this disclosure. Additionally, any given step may involve additional or fewer steps, processes, and / or components. It will also be understood that preliminary operations such as forming and machining components and assembling sub-assemblies may be performed in advance to prepare for those steps described herein. Examples include pre-manufacturing components and assembling cell 70.

[0059] like Figure 5 As shown, the first step includes forming 202 cooling strips 81-89. (As illustrated...) Figure 6 As shown, strips 81-89 can be formed in machine 130, in this case, a die / press. In other embodiments, machine 130 can be a bending machine, a roll forming machine, or other machinery. Strips 81-89 all begin with a blank 132, which is a straight section of blank having internal longitudinal or other shaped channels for fluid flow. Halfs 134 and 136 of machine 130 are joined together and act on the blank 132 to form it. Figure 7As shown, when halves 134 and 136 are reopened, blank 132 has been formed into strip 81. In this embodiment, strip 81 can be formed into any desired shape.

[0060] When the strip 81 is shaped into a desired form to mate with the cell 70, as part of method 200 and as... Figure 8 As shown, manifolds 140 and 142 are added to the end of strip 81 by 204. Manifold 140 guides fluid into and out of strip 81 and has a connection for manifold 93 ( Figure 2 The coupling element 144 is used for coupling. The manifold 142 redirects the fluid flowing from left to right through half of the strip 81 as shown, so that it returns to the manifold 140 via the strip 81. The manifolds 140 and 142 can be joined to the strip 81 by means such as welding via a welding machine 146.

[0061] Method 200 continues, applying 206 thermal interface material (TIM) 150 to strip 81 along surface 152, such as... Figure 9 As shown. TIM 150 can be any material added between cell 70 and strips 81-89 to provide thermal coupling therebetween. In an embodiment, TIM 150 can also bond cell 70 to strips 81-89. In an embodiment, TIM 150 can be a two-component mixture, such as having two components including a resin and a hardener. The application 206 of TIM 150 can be performed by an applicator 154 that dispenses TIM through nozzle 156, wherein strip 81 is positioned on fixture 158. Applicator 154 can be a machine that automatically moves across surface 152 and mixes and meters the applied TIM 150.

[0062] In method 200, when TIM 150 is in its operating state, a row of cells 70 can be added 208 to strip 81 at the applied TIM 150. Figure 10 This can be achieved using a tool 160 that assists in dimensional control. Tool 160 includes a fixing device 162 on which the strip 81 is mounted in a controlled position. For example, positioning features such as pins, blocks, or contoured surfaces can be used to position the strip 81 at a defined location in all degrees of freedom. Once positioned, the strip 81 can be clamped or otherwise held in place. Tool 160 includes a fixing device 164 on which a plurality of battery cells 70 are located. The fixing device 164 positions the battery cells 70 relative to each other according to their designed positions within the assembly module 80. Tool 160 controls the position of the battery cells 70 relative to each other and relative to the strip 81.

[0063] like Figure 11As shown, fixing devices 162 and 164 are combined together, and multiple guides 166 ( Figure 10 The fixing devices 162 and 164 are aligned. The row of cells 70 is then set onto the strip 81 as the TIM 150 is cured. In this embodiment, the open time of the TIM 150 can be one to two minutes. The fixing devices 162 and 164 have at least one stop 168 that defines a distance (H) 169 between the fixing devices 162 and 164, thereby leaving a gap 170 when the cells 70 are pressed into the applied TIM 150. The gap 170 is defined by the product design requirements and is established by H = Rt + t + Cd + ΔT, where Rt is the thickness of the strip 81, t is the gap 170, Cd is the diameter of the cells 70, and ΔT is a tolerance variation factor for the strip 81, cells 70, gap 170, and / or tool 160. Stopping the closing of the retaining devices 162 and 164 at a distance of H 169 sets the gap 170 to a defined value for dimensional control and for manipulating the selected TIM 150. In an embodiment, the gap 170 can be in the range of 0.0-0.5 mm. In other embodiments, the gap 170 can be larger. After setting the TIM 150, the retaining devices 162 and 164 are separated. The setting of the TIM 150 is completed within the tool 160 to maintain relative position. The addition step 208 performed according to the spring-loaded battery cell system 20 references the battery cells 70 relative to the strip 81 and holds them in precise position during further processing.

[0064] After adding cell 70 to strip 81, spring strip 176 is formed, as follows: Figure 12 As shown in the diagram. The spring band 176 includes a strip 81 with manifolds 140 and 142, and a plurality of cells 70 adhered to the strip 81 at defined locations according to product size requirements and on one side of surface 152 of the strip 81 via TIM 150. Figure 12 As shown, method 200 includes applying TIM 180 to surface 182 of strip 81. Surface 182 is located on the side of strip 81 opposite to surface 152. In embodiments, as further described below, TIM 180 may be a different material from TIM 150, or it may be the same material, depending on the requirements of module 80. TIM 180 may be applied by machine 184, similar to applicator 154.

[0065] like Figure 13 As shown, in method 200, another ammunition belt 177 (and other ammunition belts) similar to ammunition belt 176 can be formed. Ammunition belt 177 is added to ammunition belt 176 by 212 and pressed into TIM 180. A method similar to... Figure 10The tool 160 has a fixing device, which may include two fixing devices similar to fixing device 164 to control relative position. The gap 186 at TIM 180 is set by a tooling fixture. The gap 186 may be in the range of up to approximately 2 mm. In other embodiments, the gap 186 may have a different size than the gap 170, or it may have the same size. This assembly step can be repeated by adding 212 more springs until module 80 has the full amount of springs according to its design.

[0066] In method 200, the assembled belts 176, 177, etc., are then assembled 214 into the battery pack of RESS 40 and 216 into the vehicle 22. RESS 40 is then operated 218, such as via thermal regulation system 41.

[0067] In operation 218, the thermal regulation system 41 provides active cooling and thermal management by regulating the temperature of the RESS 40. In one embodiment, cooling is provided as needed, such as in hot weather conditions. In another embodiment, warming can be provided, such as in cold weather conditions and / or during a cold start of the vehicle 22. Liquid circulates through the strips 81-89 of the spring belt in the RESS 40 to move heat.

[0068] In embodiments, the spring-loaded battery cell system 20 facilitates the use of different materials for TIM 150 and TIM 180, and / or the use of different sized gaps for the strips on opposite sides of the battery cell 70. Reference Figure 14 The image shows a cell 70 in its final assembled state between strips 81 and 82. A TIM 150 is disposed between strip 81 and cell 70, and a TIM 180 is disposed between strip 82 and cell 70. TIM 150 and TIM 180 extend along a significant portion of the surface of cell 70 for wide-area heat exchange.

[0069] In a dual TIM strategy, relatively thinner TIM materials can be used for TIM 150. For example... Figure 14As shown, the gap 170 can be in the range of 0.0-0.5 mm. In other embodiments, the gap 170 can have different sizes. TIM 150 can be a low-viscosity adhesive-type TIM. In an embodiment, TIM 150 can be an acrylic resin, such as polymethyl methacrylate, with a viscosity in the range of 40-95 centipoise. This relatively low viscosity means that TIM 150 will be wicked into the gap and flows easily during the addition of the cell 70 to the strip 81. TIM 150 can move due to wicking and pressing. As part of method 200, TIM 150 can cure rapidly without the need for externally applied heat. In an embodiment, the addition of heat or other accelerators can be used to reduce the curing time. The thermal conductivity of TIM 150 is approximately 0.1-0.3 W / mK, thereby achieving the desired thermal management for a given gap 170 size.

[0070] exist Figure 14 In this embodiment, gap 186 can be in the range of up to approximately 2 mm. The value of gap 186 can be defined according to the thermal management requirements of the system and the tolerances of module 80. In this embodiment, TIM 180 can be a gap filler / adhesive type TIM. In this embodiment, TIM 180 can be silicone, polyurethane, epoxy resin, or other materials. In this embodiment, TIM 180 can be a two-component material, such as comprising a filler / adhesive and a hardener. In this embodiment, the sizes of gaps 170 and 186 can be balanced to achieve the desired heat transfer requirements.

[0071] In this embodiment, a dual TIM strategy can be used when gaps 170 and 186 are the same or approximately the same size, and the material selection can be customized based on the resulting gap size and heat transfer requirements. The spring-loaded battery cell system 20 allows gap 186 to be larger than gap 170, and its position is strictly controlled at the addition step 212 of method 200. This, in turn, allows for greater tolerance variations in gap 186, ensuring that interference fits and excessively large gap sizes are avoided. In other words, most of the geometry and tolerance settings are accommodated in one joint with the battery cell 70 rather than two joints. As a result, this facilitates thermal management and electrical connections, such as those with the ICB 100.

[0072] In addition to the cylindrical battery cell 70, other types of battery cells can also be used in the belt-type battery cell system 20. (Reference) Figure 15 An embodiment including a prismatic battery cell 190 is shown as an example. The battery cell 190 can be assembled in a spring strip 191. The strip 192 is straight or substantially straight to accommodate the shape of the battery cell 190. Multiple spring strips 191 can be pre-assembled and subsequently aggregated as in method 200.

[0073] Figure 16 An additional embodiment utilizing a pouch cell 194 is shown. A spring strip 195 is formed from the cell 194 and a strip 196. The strip 196 is straight or substantially straight to accommodate the cell 194. Multiple spring strips 195 can be pre-assembled and subsequently aggregated as in method 200. In other embodiments, the cells can have different shapes and the strips have shapes for accommodating the cells.

[0074] Therefore, cell placement is controlled, while providing bifacial cell cooling. Benefits include: reducing the total number of unconstrained parts during cell and strip assembly by pre-curing the cells to the strip in the spring pack using TIM, thereby reducing component and assembly complexity. The modular assembly process reduces the requirement for sequencing unique components. Errors are reduced by avoiding the accumulation of tolerances. Modular spring packs pre-assembled into sub-assemblies are formed. During spring pack formation, sub-assembly is completed while the components are held in place by tooling. During the manufacturing process, pre-curing a portion of the cell-strip joint increases assembly strength, thereby reducing the need for curing buffers or support tooling to maintain component relationships. The sub-assembled spring packs are then assembled into battery packs, such as in modules or RESS.

[0075] While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be understood that numerous variations exist. It should also be understood that the exemplary embodiments or multiple exemplary embodiments are merely examples and are not intended to limit the scope, applicability, or configuration of this disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient roadmap for implementing the exemplary embodiments or multiple exemplary embodiments. It should be understood that various changes can be made to the function and arrangement of the elements without departing from the scope of this disclosure as set forth in the appended claims and their legal equivalents.

Claims

1. A method comprising: Forming strips for removing heat from the battery system; The battery cells are assembled into rows, wherein each row is positioned between two strips in the strip; Before assembling the battery cells into a row, sub-assemblies are formed, each sub-assembly including one strip of the strip and one row of battery cells in a pre-assembled cell row; The battery cell of each sub-assembly is fixed to one of the strips in the strip by a first thermal interface material; After the battery cell of each sub-assembly is secured to its corresponding strip to become one of the pre-bonded cell rows, multiple sub-assemblies are stacked; and The battery cells of each sub-component are attached to the strip of another sub-component using a second thermal interface material to form a battery module.

2. The method according to claim 1, comprising: A first material with a first viscosity is selected as the first thermal interface material; as well as A second material with a second viscosity is selected as the second thermal interface material, wherein the value of the second viscosity is substantially higher than that of the first viscosity.

3. The method according to claim 1, comprising: Acrylic resin was selected as the first thermal interface material; as well as Choose at least one of silicone, polyurethane, and epoxy resin as the second thermal interface material.

4. The method according to claim 1, comprising: A first gap is provided between each battery cell and its corresponding strip; as well as A second gap is provided between each battery cell and one strip of the strip belonging to an adjacent pre-bonded cell array, wherein the first gap is set to be substantially smaller than the second gap.

5. The method according to claim 1, comprising: Before forming the pre-bonded cell array, the battery cells of the respective sub-assemblies are held in place relative to each other in a tool.

6. The method according to claim 5, comprising: When the pre-bonded cell array is formed to the following closed height (H), the tool is closed: H = Rt + t + Cd + ΔT, where Rt is the thickness of the strip, t is the gap between the battery cell and the strip, Cd is the diameter of the battery cell, and ΔT is the tolerance variation factor of the strip, the battery cell, and the tool.

7. The method according to claim 1, comprising: Each of the battery cells in the battery module is bonded to two strips in the strip to provide double-sided cooling for each of the battery cells.

8. The method according to claim 1, comprising: A first gap is provided between each battery cell and one of the corresponding stripes in its corresponding pre-bonded cell row; The second gap is set in one of the strips belonging to the adjacent pre-bonded cell array; and The size position is controlled and a cooling effect is provided by selecting the first gap and the second gap.

9. A system comprising: The strips are configured to remove heat from the battery system; The battery cells are arranged in rows, with each row positioned between two strips in the strip; as well as Sub-assemblies, each sub-assembly including one strip of the strip and one battery cell row of the battery cell row in a pre-bonded cell row; The battery cell of each sub-component is fixed to one of the strips by a first thermal interface material; After the battery cell of each sub-assembly is fixed to its corresponding strip to become one of the pre-bonded cell rows, the multiple sub-assemblies are configured to be stacked and fixed by a second thermal interface material to form a battery module.

10. The system of claim 9, wherein the first thermal interface material comprises a first material having a first viscosity, and the second thermal interface material comprises a second material having a second viscosity, the magnitude of which is substantially higher than the first viscosity.

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