Battery system and electric vehicle including the same

Abstract

The invention provides a battery system and an electric vehicle including the same. The battery system includes: a case; a battery cell in the case and including an exhaust gas outlet for allowing the exhaust gas flow to exit at a top side or a bottom side of the battery cell; a bottom plate covering a bottom side of the battery cell; a cross beam separating adjacent ones of the battery cells, including a lower end on the bottom plate, and extending from the bottom plate to be adjacent to a top side of the adjacent ones of the battery cells; and a cover plate extending from one of the adjacent ones of the battery cells across the cross beam to another of the adjacent ones of the battery cells to cover an upper end of the cross beam and at least partially cover a top side of the adjacent ones of the battery cells, the cover plate being configured to be fixed to the cross beam via a first fixing member.

Description

Technical Field

[0001] The present disclosure relates to a battery system and an electric vehicle including the battery system. Background Art

[0002] Recently, vehicles have been developed that are used for the transportation of goods and people and that use electricity as a source of locomotion. Such electric vehicles may be cars that are driven by an electric motor that uses energy stored in a rechargeable battery. Electric vehicles may be powered solely by batteries, or may be in the form of hybrid vehicles powered by, for example, a gasoline generator or a hydrogen fuel cell.

[0003] A hybrid vehicle may include a combination of an electric motor and a conventional internal combustion engine. Generally, an electric vehicle battery (EVB) or traction battery may be used to power the propulsion of a battery electric vehicle (BEV). Electric vehicle batteries differ from starting batteries, lighting batteries, and ignition batteries in that they are designed to provide power for sustained periods of time.

[0004] A rechargeable battery or secondary battery differs from a primary battery in that it is designed to be repeatedly charged and discharged, whereas the latter is designed to provide only an irreversible conversion of chemical energy into electrical energy. Low-capacity rechargeable batteries can be used as a power source for small electronic devices such as cellular phones, laptop computers, and video cameras, while high-capacity rechargeable batteries can be used as a power source for electric vehicles and hybrid vehicles, etc.

[0005] Generally, a rechargeable battery includes an electrode assembly, which includes a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode. Generally, a rechargeable battery may also include a shell for receiving the electrode assembly and an electrode terminal electrically connected to the electrode assembly. An electrolyte solution may be injected into the shell so that the battery can be charged and discharged by an electrochemical reaction of the positive electrode, the negative electrode, and the electrolyte solution. The shape of the shell (such as cylindrical or rectangular) may be selected based on the intended purpose of the battery. Lithium-ion (and similar lithium polymer) batteries, which are well known for their use in laptops and consumer electronics, dominate the latest batch of electric vehicles under development.

[0006] The rechargeable battery can be used as a battery module formed of a plurality of unit battery cells connected in series and / or in parallel to each other, thereby providing high density, such as for the motor drive of a hybrid vehicle. For example, the battery module can be formed by interconnecting the electrode terminals of the plurality of unit battery cells in an arrangement or configuration depending on the desired amount of electricity and in order to achieve a high-power rechargeable battery.

[0007] The battery module can be constructed in a block design or a modular design. In the block design, each battery can be connected to a common current collector structure and a common battery management system, and its units can be arranged in a housing. In the modular design, multiple battery cells can be connected together to form a sub-module, and several sub-modules can be connected together to form a battery module. In automotive applications, the battery system generally includes a plurality of battery modules connected in series to provide the desired voltage. The battery module may include a sub-module having a plurality of stacked battery cells, and each stack may include cells connected in parallel (these cells are in turn connected in series) (XpYs), or may include cells connected in series (these cells are in turn connected in parallel) (XsYp).

[0008] A battery pack is a group of any number of (usually substantially identical) battery modules. The battery modules may be configured in series, parallel, or a mixture of both to deliver a desired voltage, capacity, and / or power density. The components of a battery pack may include individual battery modules and may also include interconnects that provide electrical conductivity between battery modules.

[0009] The mechanical integration of such a battery pack includes appropriate mechanical connections between the various components of the battery module and also between the battery modules, and also the supporting structure of the vehicle. These connections and structures are designed to maintain functionality throughout the average service life of the battery system. In addition, there may be installation space and interchangeability standards (for example, in mobile applications).

[0010] Mechanical integration of the battery module can be achieved by providing a carrier frame and by positioning the battery module thereon. The battery cells or battery modules can be secured by using mating recesses in the frame or by mechanical interconnects such as bolts or screws. In other examples, the battery module can be defined by fastening side panels to the sides of the carrier frame. In addition, cover plates can be secured on top and below the battery module.

[0011] The carrier frame of the battery pack can be mounted to the load-bearing structure of the vehicle. If the battery pack is fixed to the bottom of the vehicle, a mechanical connection can be established from the bottom side, for example by bolts passing through the carrier frame of the battery pack. The frame can generally be made of aluminum or an aluminum alloy to reduce the overall weight of the structure.

[0012] The thermal management system can provide thermal control of the battery pack to safely use the battery module by efficiently emitting, releasing and / or dissipating the heat generated from its rechargeable batteries. If the heat emission / release / dissipation is not adequately performed, temperature deviations may occur between the battery cells, so that the battery module may no longer generate the expected amount of electricity. The increase in internal temperature may cause abnormal reactions in the battery cells, the charging and discharging performance of the rechargeable battery may deteriorate, and the life of the rechargeable battery may be shortened.

[0013] Exothermic decomposition of monomer components may lead to so-called thermal runaway. Generally, thermal runaway describes a process that is accelerated by increased temperature, which in turn releases energy that further increases the temperature. If the temperature increase changes the conditions in a way that causes the temperature to increase further, thermal runaway may occur, potentially leading to destructive results. In rechargeable battery systems, thermal runaway may be associated with strong exothermic reactions that are accelerated by the temperature increase. These exothermic reactions may include the combustion of combustible gas components within the battery pack housing.

[0014] For example, if a cell is heated above a critical temperature (typically above about 150°), the battery cell may transition to thermal runaway. The initial heating may be caused by a local fault (such as an internal short circuit in the battery cell, heating from a defective electrical contact, or a short circuit with an adjacent battery cell). During thermal runaway, a faulty battery cell (e.g., a battery cell with a local fault) may reach a temperature exceeding about 700°C. In addition, a large amount of hot gas may be ejected from the interior of the faulty battery cell through the exhaust port of the cell housing and into the battery pack. The main components of the exhausted gas are H2, CO2, CO, electrolyte vapor, and other hydrocarbons. The exhausted gas may be flammable and potentially toxic. The exhausted gas may also cause the gas pressure inside the battery pack to increase.

[0015] The battery cells of known battery systems are usually insulated with a plastic foil, which provides adequate electrical insulation to the side walls and the bottom within normal operating temperatures of up to about 150°C. The battery cells may be squeezed or glued into the cell compartment of the battery housing towards the bottom and the side walls, while the top side of the battery cells may usually be uncovered. During heating of the battery cell, which is damaged due to, for example, thermal runaway inside the battery cell, the plastic insulator may melt, thereby losing mechanical fixation. For example, the glue / adhesive between the battery cell and the compartment may lose its fixing ability at about 300°C, which may allow the battery cell to move (for example, if the battery cell ejects part of its contents / components during thermal runaway).

[0016] The housing of the battery cell typically includes aluminum that has a relatively low melting point (e.g., about 550°C) compared to the temperatures generated inside the battery cell during a thermal runaway event (e.g., up to about 1000°C). The relatively high pressure and temperature gradients that occur in this situation may cause the battery cell to rupture at undesirable locations (e.g., at locations other than the dedicated rupture plate of the exhaust outlet). This may result in contamination of the top side of the battery cell, potentially causing arcing and heat propagation, and potentially allowing the thermal runaway event to propagate to the remaining battery cells. Summary of the invention

[0017] An aspect of the present disclosure is to overcome or reduce at least some of the disadvantages of the prior art and to provide a battery system that more safely handles thermal runaway of one or more battery cells without damaging components of the battery system.

[0018] The present disclosure is defined by the appended claims, including functional equivalents thereof. The following description is limited thereto. Any disclosure outside the scope of the claims is intended for illustrative and comparative purposes only.

[0019] According to one aspect of the present disclosure, a battery system that can be used in an electric vehicle includes: a housing; battery cells forming a battery pack accommodated in the housing and including an exhaust outlet at the top side or the bottom side of the battery cells for allowing exhaust airflow to exit; a bottom plate covering the bottom side of the battery cells; a crossbeam separating adjacent battery cells among the battery cells, including a lower end on the bottom plate and extending from the bottom plate to be adjacent to the top side of the adjacent battery cells among the battery cells; a cover plate extending from one of the adjacent battery cells among the battery cells, across the crossbeam to another of the adjacent battery cells among the battery cells to cover the upper end of the crossbeam and at least partially cover the top side of the adjacent battery cells among the battery cells, the cover plate being configured to be fixed to the crossbeam via a first fixing member.

[0020] The base plate may be configured to be fixed to the cross beam via a second fixing member.

[0021] The second fixing member may include one or more bolts or screws.

[0022] The first fixing member may include one or more bolts or screws.

[0023] The cap plate may cover the electrode terminals at the top sides of the adjacent battery cells among the battery cells.

[0024] The cover plate may be fixed to the top sides of the adjacent battery cells among the battery cells.

[0025] The cover plate may be adapted to the contours of the top sides of the battery cells and the upper ends of the crossbars.

[0026] The cover plate may include a first thermal insulation layer and a mechanically rigid structural layer.

[0027] The battery system may further include a second thermal insulation layer between the cross beam and one of the adjacent ones of the battery cells.

[0028] The second thermal insulation layer may include a woven fabric and a matrix support material, the woven fabric including glass fibers, basalt fibers or mica fibers.

[0029] The first thermal insulation layer may include a woven fabric and a matrix support material, the woven fabric including glass fibers, basalt fibers or mica fibers.

[0030] The structural layer may include metal.

[0031] The cover plate may completely cover the top side of the battery cell.

[0032] The exhaust outlet may be at a top side of the battery cell, wherein the cover plate includes an exhaust port aligned with the exhaust outlet of the battery cell and configured to allow exhaust air flow through the cover plate.

[0033] Yet another aspect of the present disclosure relates to an electric vehicle comprising the battery system according to any one of the aforementioned aspects.

[0034] Further aspects of the disclosure are apparent from the dependent claims or the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Features will become apparent to those skilled in the art by describing the embodiments in detail with reference to the accompanying drawings, in which Figure 1 A schematic cross-sectional view of a battery system according to one or more embodiments is shown. DETAILED DESCRIPTION

[0036] Reference will now be made in detail to embodiments, examples of which are shown in the accompanying drawings. Various aspects of the embodiments and methods for implementing the embodiments will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same elements, and redundant descriptions are omitted. However, the present disclosure may be implemented in a variety of different forms and should not be construed as being limited to the embodiments shown here. Rather, these embodiments are provided as examples so that the present disclosure will be thorough and complete, and the aspects and features of the present disclosure will be fully conveyed to those skilled in the art.

[0037] Therefore, processes, elements, and techniques that are not considered necessary for one of ordinary skill in the art to fully understand the aspects and features of the present disclosure may not be described.In the drawings, the relative sizes of elements, layers, and regions may be exaggerated for clarity.

[0038] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, the use of "may" when describing embodiments of the present disclosure refers to "one or more embodiments of the present disclosure." In the following description of embodiments of the present disclosure, terms in the singular may include plural forms unless the context clearly indicates otherwise.

[0039] It will be understood that although the terms "first" and "second" are used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element can be named as a second element, and similarly, a second element can be named as a first element without departing from the scope of this disclosure. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. Expressions such as "at least one of...", when preceding a column of elements, modify the entire column of elements without modifying the individual elements in the column.

[0040] As used herein, the terms "substantially," "about," and similar terms are used as terms of approximation rather than as terms of degree, and are intended to account for the inherent deviations in measured or calculated values ​​that one of ordinary skill in the art would recognize. In addition, if the term "substantially" is used in conjunction with a feature that can be expressed using a numerical value, the term "substantially" means a range of + / - 5% of a value centered on that value.

[0041] It will be further understood that the terms “comprises,” “includes,” “including,” or “comprising,” specify properties, regions, fixed numbers, steps, processes, elements, parts, and combinations thereof, but do not exclude other properties, regions, fixed numbers, steps, processes, elements, parts, and combinations thereof.

[0042] It will also be understood that when a film, region or element is referred to as being “on” or “on” another film, region or element, it can be directly on the other film, region or element or intervening films, regions or elements may also be present.

[0043] Here, the terms "upper" and "lower" and "top side" and "bottom side" are defined according to the z-axis. For example, the top side of the battery cell is positioned at the upper part of the z-axis, and the bottom side of the battery cell is positioned at the lower part thereof. These terms may refer to the intended installation of the battery system inside an electric vehicle. In the accompanying drawings, the size of the elements may be exaggerated for clarity. For example, in the accompanying drawings, the size or thickness of each element may be arbitrarily shown for the purpose of illustration, and the embodiments of the present disclosure should not be construed as being limited thereto.

[0044] In the following description of the embodiments of the present disclosure, terms in the singular form may include plural forms unless the context clearly indicates otherwise.

[0045] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and / or the context of this specification, and should not be interpreted in an idealized or overly formal sense, unless explicitly defined as such herein.

[0046] Reference Figure 1 According to one aspect of the present disclosure, a battery system 100 is provided. The battery system 100 includes a housing and a plurality of battery cells 12 accommodated inside the housing. The housing may be referred to as a battery housing. The housing may also be considered as a cell compartment for the battery cells 12.

[0047] The battery cells 12 may be interconnected via one or more electrical connection members (e.g., busbars) contacting the corresponding electrodes / cell terminals of the battery cells 12 to form one or more battery modules / battery packs. The battery cells 12 may be arranged to form one or more battery packs. The battery cells 12 in a battery pack may be electrically interconnected (e.g., in series and / or in parallel, as described above). A plurality of battery packs may form a battery module. Two or more battery packs may be stacked to form a cell stack.

[0048] The battery cell 12 may be, for example, a prismatic or cylindrical cell. Each battery cell 12 includes a top side 12a at the upper end of the battery cell 12 and a bottom side 12b at the lower end of the battery cell 12. Each battery cell 12 includes an exhaust outlet 14 at an exhaust side 13 of the battery cell 12 (e.g., at the terminal side of the battery cell). The exhaust outlet 14 may allow exhaust gas flow to escape the battery cell 12 during thermal runaway. An exhaust valve may be provided at the exhaust outlet 14. The exhaust side 13 may be the top side 12a and / or the bottom side 12b of the battery cell 12 (e.g., one or more exhaust outlets 14 may be provided at the top side 12a and / or the bottom side 12b of the battery cell 12).

[0049] The battery system 100 may further include a mechanically rigid bottom plate 30. The battery cells 12 may be arranged on the bottom plate 30. For example, the battery cells 12 may stand upright on the bottom plate 30. The bottom plate 30 may be arranged at the lower end of the battery cells 12 (for example, the battery cells 12 may be arranged with their respective bottom sides 12b on the bottom plate). The bottom sides 12b of the battery cells 12 may contact the bottom plate 30. The bottom plate 30 may be mechanically rigid, which means that the bottom plate 30 generally lacks flexibility. The bottom plate 30 may be hard and generally unyielding at least with respect to the forces that often occur during thermal runaway of one or more battery cells 12. The bottom plate 30 may be mechanically rigid so that the bottom plate 30 can withstand the forces that often occur during thermal runaway of one or more battery cells 12 without substantially bending or breaking, and / or so that the bottom plate 30 can be structurally integrated with other components of the battery system 100 (for example, the housing to which the crossbeam 18 and / or the bottom plate 30 is fixed). Rigidity may be achieved through appropriate choice of material (eg, steel) and / or material thickness.

[0050] For example, the bottom plate 30 may extend along the entire bottom side 12b of the battery cell 12. If the exhaust side 13 of the battery cell 12 is the bottom side 12b, the bottom plate 30 may include an exhaust port aligned with the exhaust outlet 14 of the battery cell 12 to allow exhaust airflow through the bottom plate 30. The bottom plate 30 may be adapted to withstand temperatures typically encountered during thermal runaway (e.g., temperatures of at least about 700°C, or up to about 1000°C). A cooling element may be arranged at the bottom plate 30, or the bottom plate 30 itself may serve as a cooling element to enable cooling of the battery cell 12 during normal operation.

[0051] The battery system 100 may further include one or more beams 18 (e.g., alternatively named crossbars) that separate adjacent battery cells 12 among the plurality of battery cells 12. In one or more embodiments, the beams 18 may separate adjacent cells of different battery packs. The beams 18 may be arranged with their lower ends on the bottom plate 30. The beams 18 may extend from the bottom plate 30 to the top sides 12a of the adjacent battery cells 12. The beams 18 may extend upward to the position of the top sides 12a of the battery cells 12. In one or more embodiments, the top sides of the beams 18 and the top sides 12a of the adjacent battery cells 12 may have substantially the same height and / or the same position on the z-axis.

[0052] Since the cross beam 18 is arranged on the bottom plate 30, the bottom plate 30 can be considered to extend from one of the adjacent battery cells 12 to another of the adjacent battery cells 12 below the cross beam 18, thereby covering the lower end of the cross beam 18. In addition, the bottom plate 30 can at least partially cover the bottom side 12b of the adjacent battery cell 12. The bottom plate 30 can be considered as a lower cover for covering the cross beam 18 and the adjacent battery cells 12 (for example, all the battery cells 12, or at least all the battery cells 12 of one of the battery packs).

[0053] The cross beam 18 may be considered part of the housing (e.g., part of the cell compartment of the battery system). The cross beam 18 constitutes a structural component of the battery system 100, giving the battery system 100 structural integrity. The cross beam 18 may be connected (e.g., structurally connected) to the housing. The cross beam 18 may be made of aluminum.

[0054] The battery system 100 may further include a cover plate 20 that covers at least a portion of the top side 12a of the battery cell 12 and covers (e.g., completely covers) the upper end / top side of the cross beam 18. The cover plate 20 may extend from the first of the adjacent battery cells 12 to the second of the adjacent battery cells 12, thereby spanning the cross beam 18. The cover plate 20 may be considered an upper cover. The battery system 100 may include a plurality of cover plates 20 (e.g., may include a cover plate 20 for each arrangement of adjacent battery cells 12 with a cross beam 18 therebetween).

[0055] In one or more embodiments, the cover plate 20 may cover a plurality of battery cells 12 and one or more cross beams 18. In one or more embodiments, the cover plate 20 may cover all of the battery cells 12 of the battery system 100 and any cross beams 18 therebetween. If the exhaust side 13 of the battery cell 12 is at the top side 12a, the cover plate 20 may include an exhaust port aligned with the exhaust outlet 14 of the battery cell 12 to allow exhaust airflow to pass through the cover plate 20.

[0056] The cover plate 20 can be mechanically rigid in the same sense as the base plate 30 described above. The cover plate 20 being mechanically rigid can mean that the cover plate 20 lacks flexibility. The cover plate 20 can be hard and unyielding at least with respect to the forces that often occur during thermal runaway of one or more battery cells 12. The cover plate 20 is mechanically rigid so that the cover plate 20 can withstand the forces that often occur during thermal runaway of one or more battery cells 12 without substantially bending or breaking, and / or so that the cover plate 20 can be structurally integrated with other components of the battery system 100 (e.g., the crossbeam 18 to which the cover plate 20 is fixed and, optionally, the housing to which the cover plate 20 is fixed). Rigidity can be achieved by appropriate selection of material (e.g., steel) and / or material thickness.

[0057] The cover plate 20 is suitable for withstanding temperatures typically occurring during thermal runaway (e.g., temperatures of at least about 700°C, or at least about 1000°C). According to the present disclosure, the cover plate 20 can be fixed to the beam 18 via a first fixing member 40. In one or more embodiments, the first fixing member 40 may be provided to fixedly attach the cover plate 20 to at least one beam 18. The fixing member may be introduced into the beam 18 through the cover plate 20 from the outer surface of the cover plate 20. The fixing member may fix the cover plate 20 to the beam 18 in a force fit and / or form fit manner. If the battery system 100 includes multiple beams 18, the cover plate 20 may be fixed to multiple or all beams 18 via such a fixing member.

[0058] According to the present disclosure, both the bottom plate 30 and the cover plate 20 are mechanically rigid and both span the cross beam 18, wherein at least the cover plate 20 is mechanically fixed to the cross beam 18. This structure achieves a secure fixation of the battery cell 12 inside the battery compartment / housing, for example, in a vertical direction. In one or more embodiments, when the bottom plate 30, the cross beam 18, and the cover plate 20 are fixed together, the bottom plate 30, the cross beam 18, and the cover plate 20 jointly provide a vertical or z-axis fixation. The battery system 100 according to the present disclosure has improved structural integrity.

[0059] The structure of one or more embodiments including the base plate 30, the cover plate 20, and the cross beam 18 is capable of withstanding the pressures and temperatures present during thermal runaway of one or more battery cells 12. This ensures that a battery cell 12 experiencing thermal runaway does not rupture at an unwanted location, and ensures that the exhaust gas flow only leaves the cell at the exhaust outlet 14 (e.g., only a dedicated rupture plate for the exhaust outlet will rupture). In addition, melting of any plastic insulator in the battery system 100 during thermal runaway does not compromise mechanical fixation or structural integrity. In summary, a battery system 100 is provided that more safely handles thermal runaway of one or more battery cells 12 due to improved structural integrity.

[0060] According to one or more embodiments, the bottom plate 30 is fixed to the cross beam 18 via a second fixing member 42. In one or more embodiments, a second fixing member 42 is provided, which fixedly attaches the bottom plate 30 to at least one cross beam 18, or fixes the cross beam 18 to the bottom plate 30. If the battery system 100 includes multiple cross beams 18, the bottom plate 30 can be fixed to multiple or all cross beams 18 via such a fixing member. The bottom plate 30 can be fixed to the cross beam 18 in the same or similar manner as the cover plate 20 is fixed to the cross beam 18. This further improves the structural integrity of the system. The structure achieves a secure fixation of the battery cells 12 in the vertical direction inside the battery compartment / housing because the vertical or z-axis fixation is provided by the bottom plate 30, the cross beam 18 and the cover plate 20 when the bottom plate 30, the cross beam 18 and the cover plate 20 are all fixed together.

[0061] According to one or more embodiments, the first fixing member 40 may include one or more bolts and / or screws. According to one or more embodiments, the second fixing member 42 may include one or more bolts and / or screws. Bolts and / or screws may be used as one or more fixing members. For example, one or more screws may be screwed into the crossbeam 18 below the cover plate 20 through the upper end or top side of the cover plate 20. Similarly, one or more screws may be screwed into the crossbeam 18 above the base plate 30 through the lower end or bottom side of the base plate 30. Such fixing members can allow simple and secure fixation of the cover plate 20 and / or the base plate 30 and the adjacent battery cells 12 at the crossbeam 18.

[0062] According to one or more embodiments, the adjacent battery cell 12 may include an electrode terminal 16 (e.g., a cell terminal) at its top side 12a, wherein the cap plate 20 covers the electrode terminal 16. The cap plate 20 may extend over the top side 12a of the adjacent battery cell 12, and may span the region of the top side 12a including the electrode terminal 16. The region of the top side 12a including the electrode terminal 16 may be arranged adjacent to the crossbeam 18. The electrode terminal 16 may be an electrode column of the corresponding battery cell 12 for electrical connection of the battery cell 12 with one or more other battery cells 12.

[0063] Adjacent battery cells 12 may be interconnected to each other via electrical connection members that contact the electrode terminals 16 of the respective battery cells 12. The electrical connection members may span the crossbars 18. The electrical connection members may also be covered by a cover plate 20. The cover plate 20 may also cover the electrode terminals 16 of adjacent battery cells 12 (and may cover the electrical connection members) to further improve structural integrity and further improve the system's ability to withstand thermal runaway.

[0064] In addition, the cover plate 20 can protect the terminals from the exhaust gas flow (e.g., from particles of the exhaust gas flow that may be deposited on the cover plate). The cover plate 20 can cover the cross beam 18, the terminals, and / or any (multiple) electrical connection members in such a manner that the cross beam 18, the terminals, and / or any (multiple) electrical connection members are protected from exhaust products discharged by at least one of the battery cells 12 in the event of thermal runaway. This can reduce or prevent the possibility of arcing between cells.

[0065] According to one or more embodiments, the cover plate 20 may be fixed to the top side 12a of the adjacent battery cell 12. For example, the cover plate 20 is glued to the top side 12a of the adjacent battery cell 12. The cover plate 20 may be fixed to one of the adjacent battery cells 12, or to both of the adjacent battery cells 12. If the cover plate 20 also covers the electrode terminal 16, the cover plate 20 may be fixed to the top side 12a of the battery cell 12 adjacent to the electrode terminal 16, and adjacent to the side of the corresponding electrode terminal 16 away from the cross beam 18.

[0066] For example, the cover plate 20 may be fixed to the top side 12a of the left battery cell 12 with its left side end 20a, and may extend from the left side end 20a above the electrode terminal 16 of the left battery cell 12, above the crossbeam 18, and above the electrode terminal 16 of the right battery cell 12 to the right side end 20b, wherein the cover plate 20 may be fixed to the top side 12a of the right battery cell 12 through the right side end 20b. Fixing the cover plate 20 to the top side 12a of the adjacent battery cell 12 further improves the structural integrity of the system and ensures that the electrode terminal 16 remains covered by the cover plate 20 even during thermal runaway.

[0067] According to one or more embodiments, the cover plate 20 is adapted to both the contour of the top side 12a of the battery cell 12 and the contour of the upper end of the crossbeam 18. The cover plate 20 is also adapted to the contour of the electrode terminal 16 and / or the electrical connection member (if present). The cover plate 20 can be adapted to the contour of the top side 12a of the battery cell 12, the contour of the upper end of the crossbeam 18, and the contour of the electrode terminal 16. Adapting to the contour of the member may mean that the cover plate 20 includes a shape corresponding to the shape of the element covered by the cover plate 20. The contour or form of the cover plate 20 may be adapted to the contour of all elements covered by the cover plate 20. In one or more embodiments, the cover plate 20 may be adapted to the portion covered by it in a three-dimensional shape, such as the top side 12a of the battery cell 12, the upper end of the crossbeam 18, and the electrode terminal 16. This adaptation of the cover plate 20 to the covered portion makes it rare or impossible for the exhaust product to reach the covered portion to allow reliable shielding and further improve the structural integrity of the system.

[0068] According to one or more embodiments, the cover plate 20 includes a mechanically rigid structural layer 22 and a first thermal insulation layer. The structural layer 22 can give the cover plate 20 its mechanical rigidity and can lead to the above-mentioned characteristics. One or more first thermal insulation layers can provide thermal insulation from the exhaust airflow. The one or more thermal insulation layers can also provide electrical insulation. The cover plate 20 may include two first thermal insulation layers (e.g., an upper insulation layer 24 and a lower insulation layer 26), wherein the structural layer 22 is located between the upper insulation layer 24 and the lower insulation layer 26. The cover plate 20 with such (multiple) insulation layers can provide better protection for the battery cell 12 and its terminals to protect them from any exhaust airflow. Since the heating of the covered components and / or the cover plate 20 is not too severe, the cover plate 20 with such (multiple) insulation layers can improve the structural integrity of the system.

[0069] According to one or more embodiments, the battery system 100 includes a second thermal insulation layer 32 (also referred to as a thermal insulation layer 32) disposed between the crossbeam 18 and one of the adjacent battery cells 12. For example, a plurality of such thermal insulation layers 32 are provided. For example, the battery system 100 may include a thermal insulation layer 32 disposed between the crossbeam 18 and one of the adjacent battery cells 12, and may include another thermal insulation layer 32 disposed between the crossbeam 18 and another of the adjacent battery cells 12. The one or more thermal insulation layers 32 may also provide electrical insulation. An insulator may be provided between the battery cell 12 and the crossbeam 18 to allow better protection of the battery cell 12 from thermal runaway events occurring in adjacent cells. In addition, since the crossbeam 18 is not heated too severely, the insulator may improve the structural integrity of the system.

[0070] According to one or more embodiments, the first thermal insulation layer comprises a textile and a matrix support material. According to one or more embodiments, the second thermal insulation layer comprises a textile and a matrix support material. The textile may comprise one or more of glass fiber, basalt fiber or mica fiber. Mica may mean mica silicate mineral. The matrix support material may comprise a resin. The matrix support material may provide stability for the insulating layer. One or more of the insulating layers 24, 26, 32 may comprise a FR-4 coating or material. FR-4 is a National Electrical Manufacturers Association (NEMA) grade specified for glass reinforced epoxy laminates, composed of a glass fiber textile and an epoxy resin adhesive and is a flame retardant (or self-extinguishing) composite material. The textile of the insulating layer may be flexible enough to fit closely to the outer surface of an adjacent component.

[0071] According to one or more embodiments, the structural layer 22 may be a metal layer. The structural layer 22 may be a steel layer. The structural layer 22 may include metal / steel or may mainly include metal / steel. The metal (e.g., steel) is suitable for providing rigidity to the structural layer 22 and the cover plate 20, and may give the cover plate 20 mechanical rigidity. The material thickness of the structural layer 22 may be selected depending on the material so that the cover plate 20 has sufficient mechanical rigidity to withstand the forces during thermal runaway described above. According to one or more embodiments, the structural layer 22 may be a bimetallic plate (e.g., a steel alloy). The cover plate 20 may include a bimetallic composition (e.g., a steel alloy) or may mainly include a bimetallic composition (e.g., a steel alloy).

[0072] According to one or more embodiments, the cover plate 20 may completely cover the top side 12a of the battery cell 12. According to one or more embodiments, the exhaust side 13 may be arranged at the top side 12a of the battery cell 12, and the cover plate 20 includes an exhaust port aligned with the exhaust outlet 14 of the battery cell 12 for allowing the exhaust airflow to pass through the cover plate 20. In one or more embodiments, the cover plate 20 may extend along the entire top side 12a / exhaust side 13 of the battery cell 12. The cover plate 20 may completely cover the battery cell 12 at its upper side. For example, the cover plate 20 may completely cover the exhaust side 13 of the battery cell 12 except for the exhaust port, so that the exhaust airflow leaving it through the respective exhaust outlets 14 of one or more battery cells 12 can still pass through the cover plate 20. The cover plate 20 that completely covers the battery cell 12 can further improve the structural integrity of the system. If the top side 12a includes the exhaust side 13 of the battery cell 12, the cover plate 20 can completely protect the battery cell 12 at the exhaust side 13 of the battery cell 12 from the exhaust airflow and the exhaust products (e.g., particles) of the exhaust airflow, which may be deposited only on the cover plate 20 and not on the battery cell 12.

[0073] The present disclosure also relates to an electric vehicle including the battery system 100 according to the present disclosure.

[0074] Figure 1 1 is a cross-sectional view schematically showing a battery system 100 according to one or more embodiments of the present disclosure. The battery system 100 may include a case / battery case for accommodating a plurality of battery cells 12 . Figure 1 Two adjacent ones of the battery cells 12 are shown. Each of the adjacent battery cells 12 includes an exhaust side 13 having an exhaust outlet 14 at its top side 12a for allowing exhaust gas flow to leave the battery cell 12 during thermal runaway. The adjacent battery cells 12 are only partially shown. The two adjacent battery cells 12 include electrode terminals 16 at their top sides 12a for electrical connection.

[0075] Adjacent battery cells 12 are separated from each other by crossbars 18, which extend along the sides of adjacent battery cells 12 and between adjacent battery cells 12. Adjacent battery cells 12 can be arranged with their bottom sides 12b on the mechanically rigid bottom plate 30. Crossbars 18 can also be arranged with their lower ends / bottom sides on the bottom plate 30. Figure 1 As shown, the cross beam 18 may extend from the bottom plate 30 to the top side 12 a of (or adjacent to) the adjacent battery cell 12 such that the upper end / top side of the cross beam 18 is disposed at the same position on the z-axis as the top side 12 a of the adjacent battery cell 12 .

[0076] The battery system 100 may further include a mechanically rigid cover plate 20 that covers the top side 12a (including the electrode terminal 16) of the adjacent battery cells 12 and covers the upper end of the cross beam 18. In one or more embodiments, from left to right, the cover plate 20 extends from the left side end 20a above the electrode terminal 16 of the left battery cell 12, then extends above the cross beam 18, then extends above the electrode terminal 16 of the right battery cell 12, and may terminate at the right side end 20b. The cover plate 20 is adapted to the contour of the top side 12a of the battery cell 12 and the upper end of the cross beam 18. In one or more embodiments, the cover plate 20 is adapted to the contour of the electrode terminal 16 via the protruding portion 20c of the cover plate 20.

[0077] The cover plate 20 is fixed to the cross beam 18 via a first fixing member 40 (e.g., via one or more screws and / or one or more bolts). The first fixing member 40 can be introduced from the outer surface of the cover plate 20 and can extend through the cover plate 20 into the cross beam 18. In addition, the cover plate 20 can be fixed (e.g., glued) to the top side 12a of the left battery cell 12 with its left side end and fixed (e.g., glued) to the top side 12a of the right battery cell 12 with its right side end 20b. In addition, the bottom plate 30 can be fixed to the cross beam 18 via a second fixing member 42 (which can also be one or more screws and / or one or more bolts). The second fixing member 42 can be introduced from the outer surface of the bottom plate 30 and can extend through the bottom plate 30 into the cross beam 18.

[0078] When the base plate 30, the cross beam 18 and the cover plate 20 are fixed together, vertical or z-axis fixation is provided by the base plate 30, the cross beam 18 and the cover plate 20. Since the cover plate 20 and the base plate 30 are both mechanically rigid and are fixed to the cross beam 18, the rigidity of the structure can be appropriately enhanced. The structure achieves a firm fixation of the battery cell 12 relative to the vertical z-direction in the battery compartment / housing. The battery system 100 according to the present disclosure provides improved structural integrity. In addition, the structure including the base plate, the cover plate and the cross beam is capable of withstanding the pressure and temperature occurring during thermal runaway of one or more battery cells 12, which can ensure that the battery cell experiencing thermal runaway does not rupture at an unwanted location, but only ruptures at the dedicated rupture plate of the exhaust outlet 14.

[0079] For thermal and electrical insulation, the cap plate 20 may include an upper insulating layer 24 and a lower insulating layer 26 surrounding a mechanically rigid structural layer 22. The structural layer 22 may provide mechanical rigidity to the cap plate 20. In addition, insulating layers 32 may be provided on both sides of the cross beam 18, respectively, to insulate from adjacent battery cells 12. The insulating layers 24, 26, 32 may include FR-4 material.

[0080] Some reference symbols

[0081] 12: Battery cell 12a: Top side

[0082] 12b: Bottom side 13: Exhaust side

[0083] 14: Exhaust outlet 16: Electrode terminal

[0084] 18: beam 20: cover plate

[0085] 20a: left side 20b: right side

[0086] 20c: protrusion 22: structural layer

[0087] 24: Upper insulation layer 26: Lower insulation layer

[0088] 30: Bottom plate 32: Insulation layer

[0089] 40: first fixing member 42: second fixing member

[0090] 100: Battery System

Claims

1. A battery system comprising: case; a battery cell forming a battery pack accommodated in the housing and including an exhaust outlet at a top side or a bottom side of the battery cell for allowing an exhaust gas flow to exit; a bottom plate covering the bottom side of the battery cell; a crossbeam separating adjacent ones of the battery cells, including a lower end on the base plate and extending from the base plate to be adjacent to the top sides of the adjacent ones of the battery cells; A cover plate extends from one of the adjacent battery cells among the battery cells, across the cross beam to another of the adjacent battery cells among the battery cells to cover the upper end of the cross beam and at least partially cover the top side of the adjacent battery cells among the battery cells, and the cover plate is configured to be fixed to the cross beam via a first fixing member. 2 . The battery system according to claim 1 , wherein the base plate is configured to be fixed to the cross beam via a second fixing member. 3 . The battery system according to claim 2 , wherein the second fixing member comprises one or more of a bolt or a screw. The battery system according to claim 1 , wherein the first fixing member comprises one or more of a bolt or a screw. 5 . The battery system according to claim 1 , wherein the cap plate covers electrode terminals at the top sides of the adjacent battery cells among the battery cells. 6 . The battery system according to claim 1 , wherein the cover plate is fixed to the top side of the adjacent battery cell among the battery cells. 7 . The battery system of claim 1 , wherein the cover plate is adapted to contours of the top sides of the battery cells and the upper ends of the crossbars. 8 . The battery system according to claim 1 , wherein the cover plate comprises a first thermal insulation layer and a structural layer having mechanical rigidity. 9 . The battery system of claim 8 , further comprising a second thermal insulation layer between the cross beam and one of the adjacent ones of the battery cells. 10 . The battery system of claim 9 , wherein the second thermal insulation layer comprises a textile and a matrix support material, the textile comprising glass fiber, basalt fiber or mica fiber. 11 . The battery system of claim 8 , wherein the first thermal insulation layer comprises a textile and a matrix support material, the textile comprising glass fiber, basalt fiber, or mica fiber.

12. The battery system of claim 8, wherein the structural layer comprises metal. 13 . The battery system of claim 1 , wherein the cover plate completely covers the top side of the battery cell.

14. The battery system according to claim 13, wherein the exhaust outlet is at the top side of the battery cell, The cover plate includes an exhaust port, the exhaust port is aligned with the exhaust outlet of the battery cell and is configured to allow the exhaust gas flow to pass through the cover plate.

15. An electric vehicle comprising the battery system according to claim 1.

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