Battery module with a multifunctional end-plate

Abstract

The present invention provides a battery module having a multifunctional design of an end plate that enables the integration of a cooling connector and / or a high-voltage / low-voltage interface above or within the space of the end plate, thereby allowing mechanical stress to be evenly distributed to the upper regions of the first battery cell and the last battery cell.

Description

Technology Field

[0001] The present invention relates to a battery module, and more specifically, to a battery module having at least one end plate integrated with a cooling connector. Background Technology

[0002] In recent years, means of transporting goods and people have been developed using electricity as the driving source. These electric vehicles are automobiles propelled by an electric motor using energy stored in rechargeable batteries. Electric vehicles can be driven entirely by batteries or take the form of hybrid vehicles, for example, driven by a gasoline generator. Additionally, vehicles may include a combination of an electric motor and a conventional combustion engine.

[0003] Generally, an electric vehicle battery (EVB) or traction battery is a battery used for the propulsion of battery electric vehicles (BEVs). EVBs differ from starter, lighting, and ignition batteries because they are designed to supply power continuously. Rechargeable or secondary batteries differ from primary batteries in that they can be repeatedly charged and discharged, whereas the latter provide only the irreversible conversion of chemicals into electrical energy. Low-capacity rechargeable batteries are used as power sources for small electronic devices such as cellular phones, laptop computers, and camcorders, while high-capacity rechargeable batteries are used as power sources for vehicles such as hybrid cars.

[0004] Generally, a secondary battery comprises an electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive and negative electrodes, a case housing the electrode assembly, and electrode terminals electrically connected to the electrode assembly. An electrolyte solution is injected into the case to enable the charging and discharging of the battery through an electrochemical reaction between the positive electrode, the negative electrode, and the electrolyte solution. For example, the shape of the case, which may be cylindrical or rectangular, varies depending on the application of the battery. Lithium-ion (and similar lithium-polymer) batteries, widely known for use in laptops and consumer electronics, are most prominent in the latest group of electric vehicles currently under development.

[0005] Secondary batteries can be used as battery modules formed from multiple unit cell cells connected in series and / or parallel to provide high energy density, particularly for driving motors in hybrid vehicles. That is, the battery module is formed by connecting the electrode terminals of multiple unit cell cells to realize a high-output secondary battery according to the required power amount.

[0006] A battery pack is a set of multiple (preferably identical) battery modules. These can be configured in series, parallel, or a combination of both to provide the desired voltage, capacity, or power density. The components of a battery pack include individual battery modules and interconnects that provide electrical conductivity between them.

[0007] The mechanical integration of such battery packs requires proper mechanical connections between individual components (e.g., battery modules) and between the battery pack and the vehicle's support structure. These connections must be functional and safe throughout the average lifespan of the battery system. Furthermore, requirements for installation space and interoperability, particularly in mobile applications, must be met.

[0008] Mechanical integration of the battery module can be achieved by providing a carrier framework and placing the battery module on this carrier framework. The fixation of the battery cell or battery module can be achieved by recesses provided in the framework or by mechanical interconnectors such as bolts or screws. Alternatively, the battery module is constrained by fixing side plates to the sides of the carrier framework. Additionally, cover plates can be fixed to the top and bottom of the battery module.

[0009] A typical battery module may include a plurality of battery cells aligned in one direction and a heat exchange member provided adjacent to the bottom surface of the plurality of battery cells. Additionally, a pair of end plates are provided on the outside of the plurality of battery cells to face the wide surface of the battery cells.

[0010] Typically, multiple electrical connectors are installed on at least one end plate. For example, high-voltage (HV) connectors are required to connect an electrical module to an electrical circuit to supply power to the circuit. Additionally, low-voltage (LV) connectors usually connect control or measurement means (e.g., temperature sensors) integrated into the battery module to respective control devices, such as a Battery Management System (BMS) or Battery Management Unit (BMU).

[0011] Additionally, the heat exchanger may be operated by the use of a coolant or a refrigerant. Due to the constant exchange of the coolant or refrigerant in the heat exchanger, heat is released and / or dissipated from the battery cells. To this end, at least one of the end plates may be provided with a cooling connector (e.g., a hose or pipe) suitable for connecting to a refrigerant supply and / or a refrigerant discharge.

[0012] The battery pack carrier framework is mounted to the vehicle's transport structure. When the battery pack is secured to the vehicle's floor, mechanical connection can be made, for example, by bolts passing through the battery pack carrier framework from the vehicle's floor. The framework is typically made of aluminum or aluminum alloy to reduce the total weight of the structure.

[0013] A battery system according to the prior art includes a battery housing that typically serves as an enclosure to seal the battery system from the external environment and provide structural protection for the components of the battery system, regardless of any battery module structure. The embedded battery system is usually mounted as a whole in the application environment (e.g., electric vehicle). Therefore, replacing a defective system component (e.g., a defective battery submodule) requires separating the entire battery system and removing the housing first. Even a defect in a small and / or low-cost system component may lead to the separation and replacement of the entire battery system, as well as separate repairs. Since high-capacity battery systems are expensive, bulky, and heavy, the aforementioned replacement procedure is burdensome, and storing bulky battery systems becomes difficult.

[0014] Static control of battery power output and charging is insufficient to meet the dynamic power demands of various electric consumers connected to the battery system. Therefore, a steady exchange of information between the battery system and the electric consumer's controller is required. This information includes the battery system's actual state of charge (SoC), potential electric performance, charging capabilities, and internal resistance, as well as the consumer's actual or predicted power demand or surplus.

[0015] Generally, a battery system includes a battery management system (BMS) and / or a battery management unit (BMU) to process the aforementioned information. The BMS / BMU can communicate with controllers of various electrical components via an appropriate communication bus (e.g., SPI or CAN interface). Additionally, the BMS / BMU can communicate with each battery submodule, in particular with the cell monitoring circuit (CSC) of each battery submodule. The cell monitoring circuit may be further connected to the cell connection and sensing circuit (CCU) of the battery submodule, which interconnects the battery cells of the battery submodule.

[0016] Accordingly, a BMS / BMU is provided to manage the battery pack, such as protecting the battery from operating outside a safe operating area, monitoring the battery status, calculating auxiliary data, reporting data, controlling the battery environment, and certifying and / or balancing the battery.

[0017] To provide thermal control of the battery pack, a thermal management system is required to safely operate at least one battery module by efficiently dissipating, releasing, and / or dissipating heat generated from the secondary battery. If heat dissipation is not sufficiently performed, temperature deviations occur between individual battery cells, preventing at least one battery module from generating the desired amount of power. Furthermore, if the internal temperature rises, abnormal reactions occur, degrading the charging and discharging capabilities of the secondary battery and shortening its lifespan. Therefore, cell cooling is necessary to effectively dissipate, release, and dissipate heat from the cells.

[0018] As explained above, the end plate of the battery module is used for two purposes. First, the end plate serves to mechanically stabilize the position of the cells contained in the battery module. Second, the end plate is equipped with various connectors that allow the battery module to be electrically connected to external devices, such as electrical circuits or control devices, as well as to refrigerant supply and discharge devices.

[0019] US 10,017,073 B2 describes a typical design of a battery module having two end plates. In this case, one of the end plates is equipped with a refrigerant channel (refrigerant inlet and refrigerant outlet) formed of a tube having an elongated cylindrical shape protruding vertically from the end plate.

[0020] There may be several disadvantages to the configuration of such battery modules. The final design of the battery module is elongated to accommodate the space required for a long cylindrical tube. Consequently, the capacity per unit volume of the battery module is significantly reduced as the space required is utilized for components that do not contribute to the module's capacity. Additionally, since the main part of the cooling connector is positioned unsupported outside the end plate, the cooling connector is susceptible to damage from mechanical forces, such as those applied by the refrigerant supply / exhaust unit connected to it. Furthermore, the space on the end plate where the cooling connector is installed can no longer be used to accommodate other (smaller) connectors, such as low-voltage (LV) connectors and / or high-voltage (HV) connectors.

[0021] There are still differences that can be observed in the use of specific designs for battery modules. For example, end plates are used that do not extend to the full height and / or width of adjacent battery cells. In this case, mechanical stress caused by expansion forces occurring within the cell is not evenly absorbed by the end plates, which can result in bending stress at least on the surface of the battery cells adjacent to the end plates.

[0022] In addition, mechanical stress caused by expansion forces within the cell causes the end plate to bend, resulting in a decrease in the overall mechanical stability of the battery module. The problem to be solved

[0023] The object of the present invention is to provide a battery module that overcomes or reduces at least some of the disadvantages of the prior art, can be reliably connected to a refrigerant supply / discharger, and does not require additional space for a cooling connector. means of solving the problem

[0024] These objectives are achieved by a battery module as disclosed in an independent claim. Embodiments of the present invention disclosed in the following disclosures and / or dependent claims aim to solve at least one of the problems existing in the prior art.

[0025] An aspect of the present invention relates to a battery module. The battery module comprises a plurality of battery cells, a first cooling connector, a second cooling connector, a first end plate, and a second end plate. Each of the plurality of battery cells includes a front surface and a rear surface parallel to the front surface, and the front surface and rear surface of each of the plurality of battery cells are aligned along a predetermined direction so as to be perpendicular to a predetermined direction, and when viewed in a predetermined direction for any two adjacent battery cells, each subsequent battery cell has its front surface facing the rear surface of each preceding battery cell, and the first end plate has a flat front surface and a flat rear surface parallel to the front surface of the first end plate, and the front surface and rear surface of the first end plate are aligned so as to be perpendicular to a predetermined direction, and when viewed in a predetermined direction, the rear surface of the first end plate faces the front surface of the first battery cell among the plurality of battery cells.

[0026] Here, when viewed in a predetermined direction, the term "first battery cell" refers to a battery cell adjacent to the first end plate. Each of the cooling connectors has an elongated shape with a longitudinal central axis, and one of the first cooling connector and the second cooling connector is configured to be connected to an external refrigerant supply unit, while the other cooling connector is configured to be connected to an external refrigerant discharge unit. The first cooling connector is integrally formed with the first end plate, and the longitudinal central axis of the first cooling connector is perpendicular to the predetermined direction.

[0027] The battery module may include a cooling means (e.g., a heat exchanger) for cooling the battery cell, and a cooling connector may be linked or connected to the cooling means.

[0028] In one embodiment of a battery module according to the present invention, the second end plate has a front surface of a plane and a rear surface of a plane parallel to the front surface of the second end plate, and the front surface and rear surface of the second end plate are aligned perpendicular to a predetermined direction. When viewed in the predetermined direction, the front surface of the second end plate faces the rear surface of the last battery cell (e.g., a battery cell adjacent to the second end plate).

[0029] In one embodiment of the battery module according to the present invention, the second cooling connector is integral with the first end plate, and the longitudinal center axis of the second cooling connector is perpendicular to a predetermined direction.

[0030] In one embodiment of the battery module according to the present invention, the second cooling connector is integral with the second end plate, and the longitudinal center axis of the second cooling connector is perpendicular to a predetermined direction.

[0031] In one embodiment of the battery module according to the present invention, each of the first and second cooling connectors is integrated with the first and second end plates by means of a bore hole or cutout of the first and second end plates.

[0032] In one embodiment of a battery module according to the present invention, each of the first and second cooling connectors is arranged in a bore hole or cutout of the first and second end plates and is integrated with the first and second end plates, and comprises a tube or pipe made of a waterproof material including rubber, plastic (e.g., PET), or metal.

[0033] The thickness of the end plate must be selected according to the cell expansion force and cell width.

[0034] In one embodiment of the battery module according to the present invention, the thickness of the first end plate, defined by the distance between the front and rear of the first end plate, is 32 mm to 40 mm. That is, it may be at least 32 mm, preferably 38 mm, and more preferably 40 mm.

[0035] In one embodiment of the battery module according to the present invention, the thickness of the second end plate, defined by the distance between the front and rear of the second end plate, is 20 mm to 40 mm. That is, it may be at least 20 mm, preferably 30 mm. Alternatively, the thickness of the second end plate may be the same as the thickness of the first end plate.

[0036] In the following, a first direction defined as a preset direction, a second direction defined as a direction perpendicular to the first direction, and a third direction defined as a direction perpendicular to the first direction and the second direction may be defined.

[0037] In one embodiment of a battery module according to the present invention, each of the plurality of battery cells has a rectangular shape (i.e., a rectangular or diamond shape) including a first edge parallel to the first direction, a second edge parallel to the second direction, and a third edge parallel to the third direction. Additionally, the first end plate has a rectangular shape including a first edge parallel to the first direction, a second edge parallel to the second direction, and a third edge parallel to the third direction.

[0038] In one embodiment of a battery module according to the present invention, the second end plate has a rectangular shape including a first edge parallel to the first direction, a second edge parallel to the second direction, and a third edge parallel to the third direction.

[0039] In one embodiment according to the present invention, the height (size in the second direction) of each of the plurality of battery cells and the height (size in the second direction) of the first end plate are the same as each other.

[0040] In one embodiment of the battery module according to the present invention, the width (size in the third direction) of each of the plurality of battery cells and the width (size in the third direction) of the first end plate are the same as each other.

[0041] In one embodiment of the battery module according to the present invention, the height (size in the second direction) of each of the plurality of battery cells and the height (size in the second direction) of the second end plate are the same as each other.

[0042] In one embodiment of the battery module according to the present invention, the width (size in the third direction) of each of the plurality of battery cells and the width (size in the third direction) of the second end plate are the same as each other.

[0043] In the following, the height of each of the plurality of battery cells is defined as the respective length according to the second direction.

[0044] In one embodiment of the battery module according to the present invention, the height of the first end plate is the same as the height of the first battery cell (adjacent to the first end plate) when viewed in the second direction.

[0045] In one embodiment of the battery module according to the present invention, the height of the second end plate is the same as the height of the last battery cell (adjacent to the second end plate) when viewed in the second direction.

[0046] In the following, the width of each of the plurality of battery cells and the width of the first and second end plates are defined as their respective lengths according to the third direction.

[0047] In one embodiment of the battery module according to the present invention, the width of the first end plate is the same as the width of the first battery cell (adjacent to the first end plate) when viewed in the third direction.

[0048] In one embodiment of the battery module according to the present invention, the width of the second end plate is the same as the width of the last battery cell (adjacent to the second end plate) when viewed in the third direction.

[0049] In one embodiment of a battery module according to the present invention, the first end plate comprises a first extrusion profile, preferably an aluminum first extrusion profile. The pressing direction of the first extrusion profile is perpendicular to the rear surface of the first end plate.

[0050] In one embodiment of a battery module according to the present invention, the second end plate comprises a second extrusion profile, preferably an aluminum second extrusion profile. The pressing direction of the second extrusion profile is perpendicular to the front surface of the second end plate.

[0051] In the above, the pressurization direction is the direction in which the profile is extruded during the manufacture of the extrusion profile. Accordingly, a number of steps are formed within the extrusion profile in the pressurization direction.

[0052] In one embodiment of the battery module according to the present invention, at least one high-voltage connector is disposed on at least one step of the first extrusion profile.

[0053] In one embodiment of the battery module according to the present invention, at least one high-voltage connector is disposed on at least one step of the second extrusion profile.

[0054] The high-voltage connector can be integrated into the end plate by a cutout or positioned on a step within the extrusion profile geometry. The high-voltage connector is then positioned between the front and rear of each end plate and is accessible in a direction perpendicular to a predetermined first direction. Preferably, the high-voltage connector is positioned on a step adjacent to the edge of the extrusion profile, thereby simplifying access to the high-voltage connector.

[0055] In one embodiment of the battery module according to the present invention, at least one low-voltage connector is disposed on at least one step of the first extrusion profile.

[0056] In one embodiment of the battery module according to the present invention, at least one low-voltage connector is disposed on at least one step of the second extrusion profile.

[0057] The low-voltage connector can be integrated into the end plate by a cutout or positioned on a step within the extrusion profile geometry. The low-voltage connector is then positioned between the front and rear of each end plate and is accessible in a direction perpendicular to a predetermined first direction. Preferably, the low-voltage connector is positioned on a step adjacent to the edge of the extrusion profile, thereby simplifying access to the low-voltage connector.

[0058] In one embodiment of the battery module according to the present invention, at least one high-voltage connector is disposed on the front surface of the first end plate. Then, the thickness of the end plate is sufficient to integrate the high-voltage connector in front of the battery cell.

[0059] In one embodiment of the battery module according to the present invention, at least one high-voltage connector is disposed on the rear surface of the second end plate. Then, the thickness of the end plate is sufficient to integrate the high-voltage connector in front of the battery cell.

[0060] In one embodiment of the battery module according to the present invention, at least one low-voltage connector is disposed on the front surface of the first end plate. Then, the thickness of the end plate is sufficient to integrate the low-voltage connector in front of the battery cell.

[0061] In one embodiment of the battery module according to the present invention, at least one low-voltage connector is disposed on the rear surface of the second end plate. Then, the thickness of the end plate is sufficient to integrate the low-voltage connector in front of the battery cell. Effects of the invention

[0062] An embodiment of the present invention enables the integration of a cooling connector and a high-voltage / low-voltage interface above or within the space of an end plate, thereby allowing mechanical stress to be evenly distributed to the upper region of the first battery cell and the last battery cell.

[0063] In addition, embodiments of the present invention can improve the mechanical stability of the battery module by maintaining an appropriate thickness of the end plate to reduce bending of the end plate, and may not require a separate space for the cooling connector. Brief explanation of the drawing

[0064] The features will become apparent to a person skilled in the art by describing exemplary embodiments in detail with reference to the attached drawings: FIG. 1 is a schematic perspective view illustrating a typical battery module. FIG. 2a is a side view illustrating a different typical battery module. FIG. 2b is a cross-sectional view illustrating a typical other battery module. FIG. 3 is a cross-sectional view illustrating a battery module according to an embodiment of the present invention. FIG. 4 is a plan view illustrating a battery module according to an embodiment of the present invention. FIG. 5 is a side view illustrating a battery module according to an embodiment of the present invention. Specific details for implementing the invention

[0065] The following is described in detail with reference to embodiments, examples of which are illustrated in the accompanying drawings. Hereinafter, the effects and features of the present invention and the methods of implementation thereof are described with reference to the accompanying drawings. In the drawings, the same reference numerals refer to the same components, and redundant descriptions are omitted. The term “and / or” as used in this specification includes any and all combinations of one or more of the related enumerated items. Furthermore, when describing embodiments of the present invention, the use of “able to” means “one or more embodiments of the present invention.”

[0066] Although the terms “first” and “second” are used to describe various components, it will be understood that these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component.

[0067] The concept of the present invention and the features of the methods for achieving them may be more easily understood by referring to the detailed description of the embodiments below and the accompanying drawings. Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Throughout the drawings, the same reference numerals refer to the same components. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided as examples to ensure that the disclosure is thorough and complete and fully conveys the aspects and features of the present invention to those skilled in the art. Accordingly, processes, components, and techniques that are not necessary to those skilled in the art to fully understand the aspects and features of the present invention may not be described. Unless otherwise stated, similar reference numerals indicate similar components throughout the accompanying drawings and the description, and thus their description will not be repeated.

[0068] Spatial expressions such as "below," "under," "lower," "on," "on top," and "on top" are intended to compare one component or feature relative to another component or feature as depicted in the drawings. Meanwhile, since components may have different orientations or be placed in various spaces depending on the use or operation of the device, the above spatial expressions are not necessarily limited to the invention as depicted. For example, if the orientation of the device depicted in the drawings is reversed, a component described as "below," "under," or "lower" will be oriented "on," "on top," or "on top" relative to another component. Therefore, expressions such as "below" and "on top" may include both upward and downward directions. Furthermore, the device should be interpreted as being placed in various directions, such as being able to rotate 90 degrees or in another direction.

[0069] In the drawings, the relative sizes of components, layers, and regions may be exaggerated for clarity. For example, the size or thickness of each component in the drawings may be depicted arbitrarily for exemplary purposes and should not be interpreted as limiting embodiments of the invention.

[0070] When one component or layer is described as being "on top of," "connected to," or "combined" with another component or layer, it may be directly connected to the other component or layer, or there may be one or more other components or layers interposed between the components. Additionally, when one component or layer is referred to as being "between" two other components or layers, it may be understood that there is only one component or layer between the two components or layers, or that at least one intermediate component or layer exists.

[0071] The terms used in this specification are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

[0072] The terms "include" or "include" specify characteristics, domains, fixed numbers, steps, processes, elements, components, and combinations thereof, but do not exclude other characteristics, domains, fixed numbers, steps, processes, elements, components, and combinations thereof. When an expression such as "at least one" precedes a list of components, it modifies the entire list of components and does not modify the individual elements of the list.

[0073] The terms “substantially,” “about,” and similar terms used herein are used as approximations rather than degrees, and are intended to describe the inherent deviation of a measured or calculated value as perceived by a person skilled in the art. Furthermore, when the term “substantially” is used in combination with a feature that can be expressed using a numerical value, the term “substantially” indicates a range of ±5% of the value centered on the value. Moreover, when describing embodiments of the present invention, the use of “able to” means “one or more embodiments of the present invention.” Here, the terms “upper” and “lower” are defined according to the z-axis. For example, the cover is located on the upper part of the z-axis and the ground plate is located on the lower part of the z-axis.

[0074] In addition, for clarity and conciseness, "cell" and "module" may be used respectively instead of the expressions "battery cell" and "battery module."

[0075] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as generally understood by those skilled in the art to which this invention pertains. Furthermore, it will be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with that meaning in the context of the relevant technology and / or this specification, and should not be interpreted in an ideal or overly formal sense unless explicitly defined herein.

[0076] FIG. 1 is a perspective view illustrating a conventional battery module. Referring to FIG. 1, a conventional battery module (100) comprises a plurality of battery cells (10) aligned in one direction and a heat exchange member (110) provided adjacent to the bottom surface of the plurality of battery cells (10). A pair of end plates (18) are provided to face the wide surface of both battery cells (10) located on the outermost side among the plurality of battery cells (10), and a connecting plate (19) is configured to connect the pair of end plates (18) to each other. Accordingly, the plurality of battery cells (10) are fixed together. A fastening portion (18a) provided on both sides of the battery module (100) is fastened to a support plate (31) by a bolt (40). The support plate (31) is part of a housing (30).

[0077] Here, each battery cell (10) is a prismatic or rectangular cell, and the wide sides of the cells are stacked together to form a battery module. Furthermore, each battery cell (10) includes a battery case configured to accommodate an electrode assembly and an electrolyte. The battery case is sealed by a cap assembly (14). The cap assembly (14) is provided with a positive terminal (11) and a negative terminal (12) having different polarities, and a vent (13). The vent (13) acts as a passage to allow gas generated within the battery cell (10) to be discharged to the outside of the battery cell (10) as a safety means for the battery cell (10). The positive terminal (11) and the negative terminal (12) of adjacent battery cells (10) are electrically connected via a bus bar (15). The bus bar (15) can be secured by a nut (16), etc. Thus, the battery module (100) can be used as a power unit by electrically connecting a plurality of battery cells (10) as a single bundle.

[0078] Generally, a battery cell (10) generates a large amount of heat during charging / discharging. This generated heat accumulates within the battery cell (10), thereby accelerating the deterioration of the battery cell (10). Therefore, the battery module (100) further includes a heat exchange member (110) provided adjacent to the bottom surface of the battery cell (10) to cool the battery cell (10). Additionally, an elastic member (120) made of rubber or other elastic material may be interposed between the support plate (31) and the heat exchange member (110).

[0079] The heat exchange member (110) may include a cooling plate having a size corresponding to the bottom surface of a plurality of battery cells (10). For example, the cooling plate may completely overlap the entire bottom surface of all battery cells (10) in the battery module (100). Typically, the cooling plate may include a passage through which a coolant or refrigerant can move. The refrigerant circulates within the heat exchange member (110), that is, within the cooling plate, and performs heat exchange with the battery cells (10). Although not shown in FIG. 1, it is preferable to provide a cooling connector on one or both of the end plates to connect the inlet of the passage to a refrigerant supply and the outlet of the passage to a refrigerant discharge.

[0080] FIGS. 2a and 2b are a side view and a partial cross-sectional view of another typical design of a general battery module (100'). A plurality of battery cells (10a, 10b, 10c,…) are arranged in a predetermined direction (X), starting with battery cell (10a). Battery cell (10a) is hereinafter referred to as the first battery cell. This first battery cell refers to the first battery cell in the stack when the stack of cells (10a, 10b, 10c,…) is viewed in the predetermined direction (X). An end plate (18', indicated by a dashed line in the drawing) is arranged adjacent to the first battery cell (10a). Both the battery cells (10a, 10b, 10c,…) and the end plate (18') have a rectangular shape. The battery cells (10a, 10b, 10c,…) are formed identically, particularly having the same height (height is defined as the size in the Z direction), whereas the size of the end plate (18') is significantly smaller than that of the battery cells (10a, 10b, 10c,…). On the upper side of the end plate (18'), a high voltage (HV) contact surface (60) is disposed that is electrically connected to the terminal of the first battery cell (10a) and allows the battery module (100') to be electrically connected to an external circuit.

[0081] However, in the design results of a typical battery module (100'), the front upper portion of the first battery cell (10a), that is, the side of the first battery cell (10a) facing the end plate (18'), is not completely covered by the end plate (18'). Therefore, mechanical stress—so-called “cell swelling forces” caused by chemical processes inside the battery cell (10a, 10b, 10c,…) causes the front of the first battery cell (10a) to press against the end plate (18')—is absorbed only in the area of ​​the end plate (18'). On the other hand, since the opposing force by the end plate (18') is not effective in the upper area of ​​the first battery cell (10a), the upper portion of the first battery cell (10a) results in bending. In other words, at least the first battery cell (10a) of the battery module (100') is highly likely to twist during use. Such mechanical deformation of the battery cell can lead to malfunctions, including thermal runaway, which can seriously jeopardize the function of the entire battery module.

[0082] Another disadvantage lies in the extra space (70) in front of the end plate (18') required to accommodate one or more cooling connectors (not shown in the drawing). This significantly expands the overall space of a typical battery module (100'). Since the space (70) is a loss in relation to energy storage, it runs counter to the goal of achieving a high level of capacity per volume for the battery module.

[0083] To summarize the above description, the design state of the battery module (100') as illustrated in FIGS. 2a and 2b includes a small end plate (18') lower than the first battery cell (10a). Consequently, the cell swelling force generates high mechanical stress on the upper region of the first battery cell (and also on the upper region of the last battery cell if the end plates are symmetrically arranged, although not illustrated in FIGS. 2a and 2b). Furthermore, additional space is required for a cooling connector, although not illustrated.

[0084] FIGS. 3 to 5 are a front cross-sectional view, a plan view, and a side view, respectively, illustrating a battery module (200) according to an embodiment of the present invention. Referring to the drawings, a plurality of battery cells (10a, 10b, 10c,…) are arranged in a predetermined direction (X), starting with the battery cell (10a). The battery cell (10a) is hereinafter referred to as the first battery cell, and the first battery cell (10a) refers to the first battery cell in the stack when the stack of cells (10a, 10b, 10c,…) is viewed in the predetermined direction (X). A first end plate (180) is arranged adjacent to the first battery cell (10a). In FIGS. 4 and 5, the first end plate (180) is shown in a transparent manner to explain its internal structure.

[0085] The stack of battery cells (10a, 10b, 10c,…) is covered on the top by a cover plate (230) and on the sides by side plates (240a, 240b). On the side facing the first end plate (180), the stack of battery cells (10a, 10b, 10c,…) may be covered by a conventional end plate or a second end plate (not shown). The second end plate is similar to the first end plate (180) shown in the drawings and described in more detail below. The second end plate is a version mirrored (with respect to a plane perpendicular to the X-axis) to one of the versions of the first end plate (180) described below.

[0086] The height of the first end plate (180) is equal to the front height of the first battery cell (10a), that is, the side height of the first battery cell facing the first end plate (180). Consequently, the front of the first battery cell (10a) is completely covered by the first end plate (180). Accordingly, the force pressing the front of the first battery cell (10a) in the direction of the first end plate (180) can be absorbed or relieved evenly (uniformly). On the other hand, the mechanical stress applied to the first battery cell (10a) from the first end plate (180) is evenly distributed from the top to the bottom of the first battery cell (10a). Thus, bending of the first battery cell (10a), as described in the general battery module illustrated in FIGS. 2a and 2b, is avoided.

[0087] To further stabilize the battery cells (10a, 10b, 10c,…) aligned in the stack (e.g., to prevent bending of the first battery cell that may occur due to internal pressure of the battery cell in the front middle portion of the battery cell despite coverage by the end plate), the thickness of the first end plate (180) may be extended. To reduce material and prevent weight increase, it is advantageous for the first end plate (180) to be manufactured as an extrusion profile (210) (e.g., an aluminum extrusion profile). The steps (stages) (220a, 220b, 220c) of the extrusion profile (210) are preferably arranged parallel to the direction of pressure applied by the first battery cell (10a) on the first end plate (180). That is, the direction of pressure of the steps (220a, 220b, 220c) is parallel to the X-axis. This arrangement increases the bending stiffness of the extrusion profile compared to the pressure direction perpendicular to the X-axis.

[0088] In general technology, for example, compared to the battery module (100') shown in FIG. 2a and FIG. 2b, the thickness of the first end plate (180) may be extended, but the overall length (in the X direction) of the battery module (200) according to the present invention, in which the first and second cooling connectors (170a, 170b) are integrated with the first end plate (180), may be reduced compared to the general battery module (100'). The accommodation of the first and second cooling connectors (170a, 170b) may be achieved by a cylindrical cut-out (with a circular cross-section as shown in FIG. 4) within the extrusion profile (210), as shown in FIG. 3 and FIG. 5. In the present invention, the accommodation of the cooling connectors is not limited thereto and may also be achieved by a bore hole (not shown) formed in the extrusion profile. The first and second cooling connectors (170a, 170b) can be formed integrally with the first end plate (180) through a cut-out or bore hole of the extrusion profile (210).

[0089] In this embodiment, each of the first and second cooling connectors (170a, 170b) has a long shape with a longitudinal central axis, and one of the first cooling connector (170a) and the second cooling connector (170b) is configured to be connected to an external refrigerant supply unit, and the other cooling connector is configured to be connected to an external refrigerant discharge unit. The first cooling connector (170a) is integrally formed with the first end plate (180), and the longitudinal central axis of the first cooling connector (170a) is perpendicular to a preset direction (X).

[0090] In this embodiment, the first and second cooling connectors (170a, 170b) may be tubes or pipes made of a waterproof material including rubber, plastic (e.g., PET), or metal.

[0091] By the battery module (200) according to an embodiment of the present invention, any extra space for the cooling connector (see reference numeral 70 shown in FIG. 2b) can be avoided, and at the same time, the battery module (200) provides improved mechanical stability for the first and second cooling connectors (170a, 170b). That is, the first and second cooling connectors (170a, 170b) are completely protected from external mechanical shocks, such as blows or thrusts, by the surrounding first end plate (180). This further improves the functional reliability of the device. In other words, the thickness of the extrusion profile (210) is selected to provide space for the first and second cooling connectors (170a, 170b) and to improve rigidity in the area of ​​the cylindrical cutout for the first and second cooling connectors (170a, 170b).

[0092] Another advantageous aspect of the design of the battery module (200) is that the front area of ​​the first end plate (180), that is, the side area of ​​the first end plate facing the adjacent first battery cell (10a), is not occupied by the cooling connector and thus can be used to arrange a low voltage (LV) or high voltage (HV) connector that takes up less space compared to a cooling connector.

[0093] When the first end plate (180) includes the extrusion profile (210) described above, several steps (220a, 220b, 220c) of the extrusion profile (210) are available. This opens up other possibilities for accommodating low voltage (LV) or high voltage (HV) connectors in the battery module (200), that is, for placing low voltage (LV) and / or high voltage (HV) connectors in the steps of the extrusion profile. Accordingly, it is preferable to use a step (stage) close to the edge of the first end plate (180) because it allows easy access to the low voltage (LV) or high voltage (HV) connector, respectively. However, other steps (stages) may also be used for this purpose. Referring to FIGS. 3 through 5, a high voltage (HV) connector (50) is located at the highest step (220a) (in the Z-axis direction) of the extrusion profile (210) included in the first end plate (180). Inside the battery module (200), the high voltage (HV) connector (50) is electrically connected to the terminal (not shown) of the first battery cell (10a) through a suitable connector (50').

[0094] Using an extrusion profile can not only provide an end plate with enhanced stability, but also further reduce the space required for the electrical connector in that the void space inherent in the extrusion profile can be used to accommodate at least a portion of the electrical connector.

[0095] Although preferred embodiments of the present invention have been described above, the present invention is not limited thereto and can be implemented with various modifications within the scope of the claims, the detailed description of the invention, and the attached drawings, and it is obvious that such modifications also fall within the scope of the present invention. Explanation of the symbols

[0096] 10, 10a, 10b, 10c battery cells 11, 12 electrode terminals 13 vents 14 Cap Assembly 15 bus bar 16 nuts 18, 18' end plate 18a Fastening part 19 connection part 30 housing 31 Support plate 40 volts 50, 150 high voltage connector Connector for 50' high voltage connector 60 high-voltage contact surfaces Space for 70 cooling connectors 100, 100' standard battery module 110 heat exchanger 120 elastic member 170a, 170b cooling connectors 180 First end plate 200 battery modules 210 Extrusion Profile Steps of extrusion profiles 220a, 220b, and 220c 230 Cover Plate 240a, 240b side plates

Claims

Claim 1 Multiple battery cells; a first cooling connector and a second cooling connector; and includes a first end plate and a second end plate, wherein each of the plurality of battery cells includes a front surface and a rear surface parallel to the front surface, and the front surface and rear surface of each of the plurality of battery cells are aligned along a predetermined direction so as to be perpendicular to the predetermined direction, and when viewed in the predetermined direction for any two adjacent battery cells, each subsequent battery cell has its front surface facing the rear surface of each preceding battery cell, and the first end plate has a front surface and a rear surface parallel to the front surface of the first end plate, and the front surface and rear surface of the first end plate are aligned so as to be perpendicular to the predetermined direction, and when viewed in the predetermined direction, the rear surface of the first end plate faces the front surface of the first battery cell among the plurality of battery cells, and each of the cooling connectors has an elongated shape having a longitudinal central axis, and one of the first cooling connector and the second cooling connector is configured to be connected to an external refrigerant supply device, and the other cooling connector is configured to be connected to an external refrigerant discharge device, and the first end plate includes a first extrusion profile having a bore hole or a cut-out, and the first cooling A battery module having a connector having a longitudinal central axis perpendicular to the above-determined direction and formed integrally with the first end plate by a bore hole or cut-out of the first extrusion profile, wherein the pressing direction of the first extrusion profile of the first end plate is perpendicular to the rear surface of the first end plate, and the second end plate includes a second extrusion profile in which the pressing direction is perpendicular to the front surface of the second end plate, wherein at least one high-voltage connector or at least one low-voltage connector is disposed on at least one step of the first extrusion profile, and at least one high-voltage connector or at least one low-voltage connector is disposed on at least one step of the second extrusion profile. Claim 2 A battery module according to claim 1, wherein the second end plate has a front surface and a rear surface parallel to the front surface of the second end plate, and the front surface and rear surface of the second end plate are aligned perpendicular to the predetermined direction, and when viewed in the predetermined direction, the front surface of the second end plate faces the rear surface of the last battery cell. Claim 3 A battery module according to claim 1, wherein the second cooling connector has a longitudinal central axis perpendicular to the preset direction and is integrally formed with the first end plate by a bore hole or cut-out of the first extrusion profile. Claim 4 In paragraph 2, the battery module, wherein the second cooling connector has a longitudinal central axis perpendicular to the preset direction and is integrally formed with the second end plate. Claim 5 A battery module according to claim 1, wherein the first cooling connector is arranged in the bore hole or cutout and integrated with the first end plate, and comprises a tube or pipe made of a waterproof material including rubber, plastic or metal. Claim 6 In paragraph 3, the battery module comprises a second cooling connector arranged in the bore hole or cutout and integrated with the first end plate, and a tube or pipe made of a waterproof material including rubber, plastic or metal. Claim 7 A battery module according to paragraph 2, wherein the thickness of the first end plate, defined by the distance between the front and rear of the first end plate, is 32 mm to 40 mm, and the thickness of the second end plate, defined by the distance between the front and rear of the second end plate, is 20 mm to 40 mm. Claim 8 A battery module according to claim 1, wherein, when defined as a first direction defined as a predetermined direction, a second direction defined as a direction perpendicular to the first direction, and a third direction defined as a direction perpendicular to the first direction and the second direction, each of the plurality of battery cells has a rectangular shape including a first edge parallel to the first direction, a second edge parallel to the second direction, and a third edge parallel to the third direction, and the first end plate has a rectangular shape including a first edge parallel to the first direction, a second edge parallel to the second direction, and a third edge parallel to the third direction, and the second end plate has a rectangular shape including a first edge parallel to the first direction, a second edge parallel to the second direction, and a third edge parallel to the third direction. Claim 9 A battery module according to claim 8, wherein the height of each of the plurality of battery cells and the height of the first and second end plates are defined by their respective lengths along the second direction, the height of the first end plate is equal to the height of the first battery cell when viewed in the second direction, and the height of the second end plate is equal to the height of the last battery cell among the plurality of battery cells when viewed in the second direction. Claim 10 A battery module according to claim 9, wherein the width of each of the plurality of battery cells and the width of the first and second end plates are defined as their respective lengths along the third direction, the width of the first end plate is the same as the width of the first battery cell when viewed in the third direction, and the width of the second end plate is the same as the width of the last battery cell when viewed in the third direction. Claim 11 A battery module according to claim 1, wherein the first extrusion profile of the first end plate is an aluminum extrusion profile, and the second extrusion profile of the second end plate is an aluminum extrusion profile. Claim 12 delete Claim 13 delete Claim 14 delete Claim 15 Multiple battery cells; a first cooling connector and a second cooling connector; The apparatus includes a first end plate and a second end plate, wherein the plurality of battery cells are aligned along a predetermined direction such that the front of a subsequent battery cell faces the rear of a preceding battery cell in two adjacent battery cells, the first end plate faces the first battery cell among the plurality of battery cells, and the second end plate faces the last battery cell among the plurality of battery cells, the first end plate includes a first extrusion profile having a bore hole or a cut-out, the first cooling connector has an elongated shape having a longitudinal central axis and is integrally formed with the first end plate by the bore hole or cut-out of the first extrusion profile, the pressing direction of the first extrusion profile of the first end plate is perpendicular to the rear of the first end plate, and the second end plate includes a second extrusion profile in which the pressing direction is perpendicular to the front of the second end plate, at least one high-voltage connector or at least one low-voltage connector is disposed on at least one step of the first extrusion profile, and at least one high-voltage connector or at least one low-voltage connector is disposed on at least one step of the second extrusion profile Battery module being deployed.

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