Electric vehicle, cell contact unit, battery system and method of assembling same

Abstract

The invention relates to an electric vehicle, a cell contact unit, a battery system and a method of assembling the same. The battery system includes: a battery pack including a plurality of battery cells, each battery cell having a pair of electrode terminals and an exhaust valve at a terminal side of the battery cell, the terminal side of each battery cell facing a first side of the battery pack in a Z direction; a cell contact unit (CCU) carrier on a terminal side of the battery cell; and a plurality of bus bars on the electrode terminals of the battery cells and in mechanical contact with the CCU carrier. The bus bar includes a resilient member configured to apply a clamping force to the CCU carrier.

Description

Technical Field

[0001] Various aspects of embodiments of this disclosure relate to battery systems, electric vehicles including the battery systems, single-cell contact units for battery packs, and methods for assembling battery systems. Background Technology

[0002] Recently, vehicles using electricity as a power source for transporting goods and people have been developed. Such electric vehicles are automobiles that are permanently or temporarily powered by an electric motor using energy stored in rechargeable batteries. Electric vehicles can be powered solely by batteries (so-called battery electric vehicles "BEVs"), or they can include a combination of an electric motor and, for example, a conventional internal combustion engine (so-called plug-in hybrid electric vehicles "PHEVs"). BEVs and PHEVs use high-capacity rechargeable batteries designed to provide power for propulsion over a sustained period of time.

[0003] Typically, a rechargeable (or secondary) battery cell includes an electrode assembly comprising a positive electrode, a negative electrode, and a separator interposed between the electrodes. A solid or liquid electrolyte allows ions to move during the charging and discharging of the battery cell. The electrode assembly is located (e.g., housed in) a casing, with electrode terminals positioned outside the casing establishing conductive connections to the electrodes. The casing may have, for example, a cylindrical or rectangular shape.

[0004] A battery module is formed by connecting multiple battery cells together in series or parallel. For example, a battery module is formed by interconnecting the electrode terminals of multiple battery cells in a number and configuration depending on the desired power, thereby providing a high-power rechargeable battery.

[0005] Battery modules can be constructed in a block design or a modular design. In a block design, each battery cell is integrated into a common current collector structure and a common battery management system, and the cells are arranged in a housing. In a modular design, multiple battery cells are connected together to form sub-modules, and several sub-modules are connected together to form a battery module. In automotive applications, battery systems typically include multiple battery modules connected in series to provide a desired voltage.

[0006] A battery pack is a group of any number (usually the same) of battery modules or individual battery cells. Battery modules or individual battery cells can be configured in series, parallel, or a combination of both to provide desired voltage, capacity, and / or power density. The components of a battery pack include individual battery modules and interconnections that provide conductivity between the battery modules.

[0007] The exothermic decomposition of a single cell component can lead to what is known as thermal runaway. Generally, thermal runaway describes a process accelerated by an increase in temperature, which in turn releases energy that further raises the temperature. Thermal runaway occurs when conditions change in a way that alters the temperature, often resulting in destructive consequences. In rechargeable battery systems, thermal runaway is associated with a violently exothermic reaction accelerated by an increase in temperature. During thermal runaway, the temperature of a single cell rises very rapidly, and the stored energy is released very suddenly. In extreme cases, thermal runaway can cause a single cell to explode and catch fire. In milder cases, it can cause irreparable damage to the cell.

[0008] When a battery cell is heated above its critical temperature (e.g., above approximately 150°C), it may enter thermal runaway. Typically, temperatures outside the safe zone on the low or high side can cause irreversible damage to the battery cell and thus potentially trigger thermal runaway. Thermal runaway can also occur due to internal or external short circuits within the battery cell or poor battery maintenance. For example, overcharging or fast charging can lead to thermal runaway.

[0009] During thermal runaway, the faulty battery cell can reach temperatures exceeding approximately 700°C. Furthermore, a large amount of hot gas is ejected from the faulty cell into the battery pack through vents in the cell casing. The main components of the emitted gases are H2, CO2, CO, electrolyte vapor, and other hydrocarbons. Therefore, the emitted gases are flammable and potentially toxic. The emitted gases also cause an increase in pressure within the battery pack. In the worst-case scenario, the high temperature causes this process (e.g., thermal runaway) to spread to neighboring cells and ignite within the battery pack. At this stage, the fire is difficult to extinguish.

[0010] The conventional venting design for batteries involves allowing the exhaust gas stream from the individual cells to expand into the battery casing and escape to the outside (e.g., to the environment surrounding the battery casing) through a casing vent valve. However, the hot exhaust gas stream from the individual cells can flow into and remain in tolerance-dependent gaps beneath the cell contact unit carrier (which covers and contacts the cells in the battery pack). The hot exhaust gas stream then heats components inside the battery casing (such as other cells in the battery pack). For example, particles from the exhaust gas stream can deposit on the individual cells, which can cause heat propagation and potentially trigger thermal runaway in adjacent cells, leading to thermal runaway in additional (e.g., adjacent) cells within the battery pack. Summary of the Invention

[0011] Embodiments of this disclosure provide a battery system that more safely handles thermal runaway in one or more of its battery cells.

[0012] This disclosure is defined by the appended claims and their equivalents. The following description is subject to this limitation. Any disclosure outside the scope of the claims and their equivalents is intended for illustrative and comparative purposes.

[0013] According to one embodiment of this disclosure, a battery system includes: a battery pack comprising a plurality of battery cells, each battery cell having a pair of electrode terminals and an vent valve at the terminal side of the battery cell, the terminal side of each battery cell facing a first side of the battery pack in the Z direction; a cell contact unit (CCU) carrier on the terminal side of the battery cells; and a plurality of busbars on the electrode terminals of the battery cells and in mechanical contact with the CCU carrier. The busbars include elastic members configured to apply a clamping force to the CCU carrier.

[0014] According to embodiments of this disclosure, the battery system may further include a heat-resistant cell protective cover disposed between the CCU carrier and the battery cell.

[0015] According to an embodiment of the present disclosure, the elastic member of the busbar can be configured to apply a clamping force to the CCU carrier to press the CCU carrier onto the terminal side of each battery cell in the Z direction via the heat-resistant cell protective cover.

[0016] According to embodiments of the present disclosure, the CCU carrier may include a CCU elastic member configured to apply a CCU clamping force to the heat-resistant cell protective cover to press the heat-resistant cell protective cover onto the terminal side of each cell in the Z direction.

[0017] According to embodiments of this disclosure, the heat-resistant monomer protective cap may include mica and / or aerogel.

[0018] According to embodiments of this disclosure, when the busbar is on the electrode terminals, the elastic member of the busbar may include a spring protrusion and / or a preloaded section in the Z direction toward the battery cell.

[0019] According to embodiments of this disclosure, the CCU carrier and / or heat-resistant cell protective cover may have recesses and / or groove-shaped openings arranged between adjacent cell cells.

[0020] According to embodiments of this disclosure, the vent valve of each battery cell can be arranged between the electrode terminals of the respective battery cell, and the size of the CCU carrier and / or the heat-resistant cell protective cover can be set such that the CCU carrier and the heat-resistant cell protective cover are arranged in the terminal side region of the battery cell between the electrode terminals of the battery cell.

[0021] According to embodiments of this disclosure, the elastic member can be configured to apply a clamping force sufficient to secure the CCU carrier to the battery cell to the CCU carrier.

[0022] According to embodiments of this disclosure, the battery system may further include a heat-resistant touch-protective housing mechanically bonded to the CCU carrier and covering the busbar.

[0023] According to embodiments of this disclosure, a heat-resistant touch protective housing may partially cover the side surface of a battery cell in the Z direction to provide heat resistance between adjacent battery cells.

[0024] According to embodiments of the present disclosure, the CCU carrier may include a support section for supporting one end of the heat-resistant touch protective shell and extending in the Z direction between the CCU carrier and the heat-resistant touch protective shell.

[0025] According to another embodiment of this disclosure, an electric vehicle includes the battery system described above.

[0026] Another embodiment of this disclosure provides a cell contact unit (CCU) for a battery pack. The battery pack includes a plurality of battery cells, each battery cell having a pair of electrode terminals and an vent valve at the terminal side of the battery cell. The terminal side of each battery cell faces a first side of the battery pack in the Z direction. The CCU includes a CCU carrier and a plurality of busbars on the CCU carrier. The busbars include elastic members configured to apply a clamping force to the CCU carrier when the CCU carrier is on the battery pack to press the CCU carrier against the terminal side of each battery cell in the battery pack in the Z direction.

[0027] Another embodiment of this disclosure provides a method for assembling a battery system. The method includes: providing a battery pack comprising a plurality of battery cells, each battery cell having a pair of electrode terminals and an exhaust valve at the terminal side of the battery cell, the terminal side of each battery cell facing a first side of the battery pack in the Z direction; providing a CCU as described above; and arranging a CCU carrier on the terminal side of each battery cell of the battery pack, and arranging a busbar of the CCU on the electrode terminals of the battery cells.

[0028] Further aspects and features of this disclosure may be understood from the dependent claims and / or the following description. Attached Figure Description

[0029] The aspects and features of this disclosure will become apparent to those skilled in the art from the detailed description of embodiments thereof with reference to the accompanying drawings, in which:

[0030] Figure 1 This is a schematic cross-sectional view of a battery system according to an embodiment of the present disclosure.

[0031] Figure 2 yes Figure 1 The image shows a top view of the battery system.

[0032] Figure 3 It is cut along the stacking direction. Figure 1 The diagram shows a schematic cross-sectional view of the battery system.

[0033] Figure 4 This describes an assembly method according to embodiments of the present disclosure. Figure 1 The diagram shows a schematic flowchart of the steps of the method for the battery system. Detailed Implementation

[0034] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. Aspects and features of this disclosure and methods of implementation thereof will be described with reference to the accompanying drawings. However, this disclosure may be implemented in a variety of different forms and should not be construed as limited to the embodiments shown herein. Rather, these embodiments are provided as examples so that this disclosure will be thorough and complete and will fully convey the aspects and features of this disclosure to those skilled in the art.

[0035] Therefore, processes, elements, and techniques that are not considered essential for a full understanding of the aspects and features of this disclosure by one of ordinary skill in the art may be omitted or only briefly described. It will be understood that when an element or layer is referred to as being "on" another element or layer, "connected to," or "bonded to" another element or layer, it may be directly on, directly connected to, or bonded to the other element or layer, or one or more intermediate elements or layers may be present. When an element or layer is referred to as being "directly on" another element or layer, "directly connected to," or "directly bonded to" another element or layer, no intermediate elements or layers are present. For example, when a first element is described as being "bonded" or "connected" to a second element, the first element may be directly bonded to or connected to the second element, or the first element may be indirectly bonded to or connected to the second element via one or more intermediate elements.

[0036] In the figures, the dimensions of various elements, layers, etc., may be exaggerated for clarity. The same reference numerals denote the same elements. As used herein, the term “and / or” includes any and all combinations of one or more of the related listed items. Furthermore, the use of “may” when describing embodiments of this disclosure refers to “one or more embodiments of this disclosure.” Expressions such as “at least one of…” and “any one of…” modify the entire column of elements without modifying any individual element within that column when following a list of elements. For example, the expression “at least one of a, b, or c” means only a, only b, only c, both a and b, both a and c, both b and c, all a, b, and c, or variations thereof. As used herein, the terms “use,” “using…,” and “being used” may be considered synonymous with the terms “utilize,” “using…,” and “being exploited,” respectively.

[0037] It will be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or segment from another element, component, region, layer, or segment. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0038] For ease of description, spatial relation terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein to describe the relationship between one element or feature as shown in the figure and other elements(s) or features(s). It will be understood that, in addition to the orientation depicted in the figure, spatial relation terms are also intended to cover different orientations of the device in use or operation. For example, if the device in the figure is flipped, the element described as “below” or “under” other elements or features will be oriented “above” or “on” other elements or features. Therefore, the term “below” can cover both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relation descriptors used herein should be interpreted accordingly.

[0039] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit this disclosure. As used herein, the singular form “a” is intended to include the plural form as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprising,” “including,” “including,” and / or “containing” as used in this specification indicate the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0040] In view of the overall nature of this disclosure, those skilled in the art will understand that each suitable feature of the various embodiments of this disclosure may be combined in part or in whole or in combination with each other, and may be technically interlocked and operated in various suitable ways, and unless otherwise stated or implied, each embodiment may be implemented independently of each other or in combination with each other in any suitable way.

[0041] As used herein, the terms “substantially,” “about,” and similar terms are used as approximate terms rather than terms of degree and are intended to explain the inherent biases of measured or calculated values ​​that will be recognized by one of ordinary skill in the art. Furthermore, if the term “substantially” is used in combination with a feature that can be expressed numerically, the term “substantially” indicates a range of + / - 5% of the value centered on that value.

[0042] Electronic or electrical devices and / or any other related devices or components according to embodiments of the present disclosure described herein can be implemented using any suitable hardware, firmware (e.g., application-specific integrated circuits), software, or a combination of software, firmware, and hardware. Furthermore, various components of these devices can be implemented on flexible printed circuit films, tape-on packages (TCPs), printed circuit boards (PCBs), or formed on a substrate. The electrical connections or interconnections described herein can be implemented, for example, by wires or conductive elements on a PCB or other circuit carrier. Conductive elements may include metallizations, such as surface metallizations and / or pins, and / or may include conductive polymers or ceramics. Furthermore, electrical energy can be transmitted wirelessly, such as through the use of electromagnetic radiation and / or light.

[0043] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will also be understood that terms (such as those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and / or the context of this specification, and shall not be interpreted in an idealized or overly formal sense, unless expressly defined herein.

[0044] According to one embodiment of this disclosure, a battery system includes a battery pack. The battery pack includes a plurality of battery cells. Each battery cell has a pair of electrode terminals and an vent valve disposed on the terminal side of the battery cell. The terminal side of each battery cell faces a first side of the battery pack in the Z direction. Each vent valve can be configured to allow vent gas flow from the respective battery cell during thermal runaway of the respective battery cell. For example, the vent valve can open (e.g., rupture) when a reference pressure (e.g., a predetermined pressure) is exceeded. The vent valve is provided at or in the vent outlet of the battery cell (such as in an vent port). The battery cells can be housed within a battery casing of the battery pack and / or battery system. The battery cells can be arranged or stacked in a stacking direction to form one or more cell stacks. The battery cells can be interconnected via electrical connectors (e.g., busbars) contacting the respective electrode terminals of the battery cells to form one or more battery modules / battery packs. The battery cells can be arranged to form one or more battery packs. In the battery pack, the battery cells can be electrically interconnected, for example, in series and / or in parallel. A plurality of these battery packs can form a battery module. The battery cell can be, for example, a prismatic cell.

[0045] The battery system further includes a cell contact unit (CCU) carrier disposed on the terminal side of each cell. The CCU carrier may have a rectangular shape. However, the CCU carrier is not limited to a rectangular shape. The CCU carrier may have any suitable shape for assembly into the battery pack; for example, it may be square or oval. The CCU carrier may further include measuring lines for transmitting at least one physical property of the cell. The physical property may be, for example, the voltage, current, or temperature of the cell. The CCU carrier may be attached to the terminal side of each cell, for example, by fastening elements such as screws, bolts, or adhesives.

[0046] The battery system further includes a plurality of busbars. One of the busbars is disposed on the electrode terminals of a battery cell. For example, the busbar can be attached to the electrode terminals by, for example, soldering. The busbar further mechanically contacts the CCU carrier. Mechanical contact exists between the busbar and a surface of the CCU carrier facing away from the battery pack. For example, a first section (or a first portion) of the busbar is disposed on the electrode terminal of the battery cell (e.g., soldered to the electrode terminal of the battery cell), and a second section (or a second portion) of the busbar opposite to its first section is in mechanical contact with the CCU carrier.

[0047] Each busbar includes a resilient member configured to apply a clamping force to the CCU carrier, pressing the CCU carrier against the terminal side of each battery cell in the Z direction. For example, the busbar is mechanically coupled to the CCU carrier by the applied clamping force. Therefore, the resilient member is configured to apply a clamping force to the CCU carrier sufficient to individually close tolerance-dependent gaps in the Z direction between the battery cells and the CCU carrier. Due to the clamping force applied by the resilient member, gaps (e.g., tolerance-dependent gaps) in the Z direction between the battery cell top cover and the CCU carrier can be prevented (e.g., closed). In other words, the seal between the battery cell top cover and the CCU carrier can be improved. The resilient member can be integrally formed with the busbar.

[0048] If one of the battery cells is affected by (or experiences) thermal runaway, the hot exhaust gas flow is discharged from the affected battery cell through its exhaust outlet. Because gaps (e.g., tolerance-dependent gaps) in the Z direction between the battery cell top cover and the CCU carrier are prevented, the hot exhaust gas flow cannot flow or remain under the CCU carrier, and the risk of thermal runaway propagating to additional battery cells (such as adjacent battery cells in a battery pack) is reduced.

[0049] According to one embodiment, the battery system further includes a heat-resistant cell protector disposed between the CCU carrier and the individual battery cells. The heat-resistant cell protector provides additional thermal protection, for example, during thermal runaway. Hot exhaust gas streams can heat components inside the battery housing (such as other battery cells). For example, particles from the exhaust gas stream can deposit on the battery cells, which can lead to heat propagation and potentially trigger thermal runaway in adjacent battery cells. To protect the battery cells, a heat-resistant cell protector can be provided that covers the battery cells at the terminal side. For example, the heat-resistant cell protector can be arranged such that it covers multiple battery cells at the terminal side of multiple battery cells. For example, the heat-resistant cell protector can cover the top side of the battery cells. In some embodiments, the heat-resistant cell protector can cover all the battery cells in a plurality of battery cells; for example, the heat-resistant cell protector can extend above the terminal side of all the battery cells in a plurality of battery cells. The heat-resistant cell protector can be attached to the terminal side of each battery cell by fastening elements such as screws, bolts, or adhesives.

[0050] According to another embodiment, the elastic member of the busbar is further configured to apply a clamping force to the CCU carrier, causing the CCU carrier to press against the terminal side of each battery cell in the Z direction via the heat-resistant cell protective cover. Because the elastic member of the busbar also presses the heat-resistant cell protective cover against the terminal side of the battery cell, the gap between the heat-resistant cell protective cover and the top cover of the battery cell can be closed (or prevented), and the seal of the heat-resistant cell protective cover can be improved. Therefore, hot exhaust gas cannot flow or linger under the heat-resistant cell protective cover, thereby further reducing the risk of thermal runaway propagating to additional battery cells (such as adjacent battery cells in a battery pack).

[0051] According to another embodiment, the CCU carrier includes one or more CCU elastic members configured to apply a CCU clamping force to the heat-resistant cell protective cover, such that the heat-resistant cell protective cover is pressed against the terminal side of each battery cell in the Z direction. Due to the CCU elastic members, the heat-resistant cell protective cover does not require a separate fixing element, and battery system assembly can be simplified. When the CCU carrier is disposed on the terminal side of each battery cell, the CCU elastic members(s) may include spring protrusions and / or pre-loaded sections in the Z direction toward the battery cell. The CCU elastic members may be integrally formed with the CCU carrier. For example, the spring protrusions and / or pre-loaded sections in the Z direction toward the battery cell may be integrally formed with the CCU carrier.

[0052] According to another embodiment, the heat-resistant monolayer protective cap comprises or is composed of mica and / or aerogel. Mica (which may refer to mica silicate minerals) and aerogel (which is a synthetic porous ultralight material derived from gel) are heat-resistant materials.

[0053] According to another embodiment, when the busbar is disposed on the electrode terminals, the elastic member of the busbar includes a spring protrusion and / or a section preloaded toward the battery cell in the Z direction. The spring protrusion and / or the section preloaded toward the battery cell in the Z direction can be integrally formed with the busbar.

[0054] According to another embodiment, the CCU carrier and / or heat-resistant cell protective cover have recesses and / or slots (e.g., groove-like openings) arranged between adjacent cell units. The recesses (such as material-weakened portions) or slots (such as elongated slits) between adjacent cell units facilitate individual movement of the CCU carrier (relative to individual cell units) caused by the individual elastic members of the busbars of each cell unit, thereby better compensating for differences between cell units in the Z-direction. For example, it can better prevent tolerance-related gaps between the cell unit top cover and the CCU carrier or heat-resistant cell protective cover. For example, the recesses and / or slots increase the flexibility of the CCU carrier and / or heat-resistant cell protective cover. The recesses and / or slots extend in a direction orthogonal to the Z-direction and the stacking direction of the multiple cell units.

[0055] According to another embodiment, the vent valve of each battery cell is arranged between the electrode terminals of the respective battery cell. The dimensions of the CCU carrier and / or the heat-resistant cell protective cover are configured such that the CCU carrier and / or the heat-resistant cell protective cover are arranged in the terminal-side region of the battery cell between the electrode terminals of the battery cell. For example, the CCU carrier and / or the heat-resistant cell protective cover are fitted into the region(s) between the electrode terminals of the battery cell and do not extend above the electrode terminals.

[0056] According to another embodiment, the elastic member is configured to apply a clamping force to the CCU carrier sufficient to secure the CCU carrier to the battery cell. For example, this clamping force is higher than a threshold indicating the time between securing and releasing the CCU carrier. Therefore, no other securing of the CCU carrier (such as screwing the CCU carrier to the battery pack / system housing) is required. That is, the CCU carrier is held in place solely by the clamping force applied from the elastic member of the busbar. In other words, without the elastic member of the busbar, the CCU would be loosely mounted on the battery cell.

[0057] According to another embodiment, the battery system further includes a heat-resistant touch-protective housing mechanically bonded to the CCU carrier. The heat-resistant touch-protective housing covers the busbar, for example, preventing touch at least in the Z-direction. For example, when viewed in the Z-direction, the heat-resistant touch-protective housing covers the busbar. The heat-resistant touch-protective housing can be secured to the CCU carrier via clips; that is, it can be clipped onto the CCU carrier.

[0058] According to another embodiment, the heat-resistant touch protective housing further partially covers the side sections of the battery cells in the Z direction to provide heat resistance between adjacent battery cells.

[0059] According to another embodiment, the CCU carrier includes a support section for supporting one end of the heat-resistant touch protective housing and extending in the Z direction between the portion of the CCU carrier parallel to the terminal side of the battery cell and the heat-resistant touch protective housing.

[0060] Embodiments of this disclosure also provide an electric vehicle that includes a battery system as described herein, for example, as a traction battery.

[0061] Embodiments of this disclosure also provide a cell contact unit (CCU) for a battery pack. The battery pack includes a plurality of battery cells, each battery cell having a pair of electrode terminals and an vent valve disposed on the terminal side of the battery cell. The terminal side of each battery cell faces a first side of the battery pack in the Z direction. The aspects and features described above for the battery pack can be similarly applied to the battery pack with CCU.

[0062] The CCU includes a CCU carrier and multiple busbars disposed on the CCU carrier. Each busbar includes an elastic member configured to apply a clamping force to the CCU carrier, such that when the CCU carrier is disposed on the battery pack, the CCU carrier is pressed in the Z direction against the terminal side of each of the multiple battery cells in the battery pack. For example, the busbars are held by the CCU carrier such that the CCU carrier, including the measuring cables, and the busbars can be positioned together on the battery pack (e.g., a stack of battery cells) before the busbars are soldered to the cell terminals (or electrode terminals). This can thus facilitate the assembly of the battery system. The busbars have corresponding degrees of freedom of movement (e.g., play) in the Z direction, allowing them to press the CCU carrier against each battery cell.

[0063] Furthermore, embodiments of this disclosure provide a method for assembling a battery system (i.e., the battery system described above).

[0064] According to one step of the method, a battery pack is provided, the battery pack comprising a plurality of battery cells, each battery cell having a pair of electrode terminals and an vent valve disposed on the terminal side of the battery cell. The terminal side of each battery cell faces a first side of the battery pack in the Z direction.

[0065] According to another step of the method, a CCU is provided, namely the CCU described above.

[0066] According to another step, the CCU carrier is disposed on the terminal side of each battery cell in the battery pack, and the busbar of the CCU is disposed on the electrode terminal of the battery cell.

[0067] Figure 1 This is a schematic cross-sectional view of a battery system 100 according to an embodiment of the present disclosure, taken along the longitudinal direction of a single battery cell 12. Figure 2 and Figure 3 They are shown respectively Figure 1 The diagram shows a top view and a schematic cross-sectional view of the battery system 100 taken along the stacking direction.

[0068] The battery system 100 includes a battery pack 10 comprising multiple battery cells 12. For simplicity, Figure 2 and Figure 3 An example of a battery pack 10 having two battery cells 12 is depicted. However, this is only an example, and the battery pack 10 may include more than two battery cells 12. For example, the battery pack 10 may include 3, 4, 5, 6, or any suitable number of battery cells 12. The battery cells 12 are prismatic cells stacked along the stacking direction X to form a battery cell stack (see, for example, [link to previous section]). Figure 2 and Figure 3 ).

[0069] Each battery cell 12 includes a pair of electrode terminals 14 and an vent valve 16 disposed between the electrode terminals 14 on the terminal side of the battery cell 12. The terminal side of each battery cell 12 faces the first side of the battery pack 10 along the Z direction. Figure 1 and Figure 3 In this context, the Z-direction corresponds to the vertical direction of the image plane, that is, from top to bottom or vice versa. In other words, the Z-direction can refer to the height direction of the battery cell 12.

[0070] The battery system 100 further includes a plurality of busbars 20 and a cell contact unit (CCU) carrier 18 disposed on the terminal side of each battery cell 12. Some of the busbars 20 are disposed on the electrode terminals 14 of the battery cells 12. According to the illustrated embodiment, each busbar 20 is attached to a corresponding electrode terminal 14 of the battery cell 12, for example, by welding. For example, a first section (or a first portion) of the busbar 20 is welded to the electrode terminal 14 of the battery cell 12. The length of the first section of the busbar 20 may exceed half the length of the busbar 20. Figure 1 As shown, the busbar 20 further mechanically contacts the CCU carrier 18. The mechanical contact between the surfaces of the busbar 20 and the CCU carrier 18 is opposite to the first side of the battery pack 10. A second section (or second portion) of the busbar 20 mechanically contacts the CCU carrier 18. The second section of the busbar 20 is opposite to its first section.

[0071] Each busbar 20 includes an elastic member 22 configured to apply a clamping force (e.g., clamping pressure) to the CCU carrier 18, causing the CCU carrier 18 to be pressed along the Z-direction against the terminal side of each battery cell 12. The busbar 20 (particularly its second section) is mechanically coupled to the CCU carrier 18 by the applied clamping force. The elastic member 22 is configured to apply a clamping force to the CCU carrier 18 sufficient to individually close tolerance-dependent gaps in the Z-direction between the battery cell 12 and the CCU carrier 18. Figure 3 As shown, for example, the left battery cell 12 has a smaller height in the Z direction than the right battery cell 12, which is taller in the Z direction. This typically results in a tolerance-related gap between the top of the left battery cell 12 and the CCU carrier 18. However, this gap can be prevented by the clamping force applied by the elastic member 22. For example, the contact between the battery cell 12 and the CCU carrier 18 can be improved (e.g., sealed), and thermal runaway to the attached battery cell 12 can be mitigated (e.g., to...). Figure 3 The spread of the adjacent battery cell 12 on the right side. Due to the tolerance-related gap in the left battery cell 12, the elastic member 22 of the left battery cell 12 contracts less than the elastic member 22 of the right battery cell 12. That is, the battery system 100 includes tolerance compensation along the Z direction.

[0072] The elastic member 22 of the busbar 20 includes a spring protrusion. For example, the elastic member 22 is shaped as a (e.g., rounded) groove extending along the X direction (e.g., see [link]). Figure 1 and Figure 2 The X direction can refer to the stacking direction X. Additionally or alternatively, the elastic member 22 can be formed as a segment of the busbar 20, which is preloaded (e.g., bent or plastically deformed) in the Z direction toward the cell 12 when the busbar 20 is disposed on the electrode terminal 14.

[0073] like Figure 1 As shown, the battery system 100 further includes a heat-resistant cell protective cover 24 disposed between the CCU carrier 18 and the battery cell 12. The heat-resistant cell protective cover 24 is arranged to cover the battery cell 12 on the terminal side (e.g., see...). Figure 2 For example, a heat-resistant cell protective cover 24 covers the top side of the battery cell 12. The heat-resistant cell protective cover 24 can extend above the terminal side of the battery cell 12. Because the heat-resistant cell protective cover 24 is arranged between the CCU carrier 18 and the battery cell 12, the clamping force applied to the CCU carrier 18 from the elastic member 22 of the busbar 20 is also applied to the heat-resistant cell protective cover 24. Therefore, the existence of a gap between the CCU carrier 18 and the heat-resistant cell protective cover 24 can also be reduced or prevented.

[0074] To further reduce the gap between the CCU carrier 18 and the heat-resistant cell protective cover 24, the CCU carrier 18 includes a CCU elastic member 26. The CCU elastic member 26 is similar to the elastic member 22 of the busbar 20. The CCU elastic member 26 is configured to apply a CCU clamping force to the heat-resistant cell protective cover 24, such that the heat-resistant cell protective cover 24 is pressed against the terminal side of the battery cell 12 in the Z direction. The CCU elastic member 26 may include spring protrusions, for example, grooves parallel to the grooves in the elastic member 22, such as (e.g., rounded) grooves extending along the stacking direction X. Additionally or alternatively, when the CCU carrier 18 is disposed on the battery cell 12, the CCU elastic member 26 may be formed as a pre-loaded section toward the battery cell 12 in the Z direction.

[0075] For example, the CCU carrier 18 and the heat-resistant cell protective cover 24 can be loosely disposed on the battery cell 12 to be secured (e.g., secured only) by clamping forces applied from the elastic member 22 and the CCU elastic member 26. For example, the CCU carrier 18 and the heat-resistant cell protective cover 24 can be clamped between the busbar 20 welded to the electrode terminal 14 and the top cover of the battery cell 12. Therefore, the CCU carrier 18 and the heat-resistant cell protective cover 24 do not require separate securing elements.

[0076] like Figure 2 As shown, the CCU carrier 18 and the heat-resistant cell protective cover 24 have slots 34 (e.g., elongated slits) arranged between adjacent cell 12 (e.g., above the gap between cell 12 along the vertical direction Z). In the illustrated embodiment, three slots 34 are shown. The slots 34 extend in directions orthogonal to the Z direction and the stacking direction X. For example, the slots 34 extend in the Y direction orthogonal to the stacking directions X and Z. The slots 34 increase the flexibility of the CCU carrier 18 and the heat-resistant cell protective cover 24, thereby improving the bending of the CCU carrier 18 on a per-cell basis. Therefore, tolerance-related gaps between the cell 12 and the CCU carrier 18 and the heat-resistant cell protective cover 24 can be prevented more effectively.

[0077] The battery system 100 further includes a heat-resistant touch-protective housing 28 mechanically bonded to the CCU carrier 18. The heat-resistant touch-protective housing 28 covers the busbar 20 in the Z-direction. The heat-resistant touch-protective housing 28 also partially covers the side sections of the battery cells 12 in the Z-direction to provide heat resistance between adjacent battery cells 12. The heat-resistant touch-protective housing 28 has an L-shaped cross-sectional shape, for example as... Figure 1 As shown in the figure. However, the battery system 100 is not limited to this, and in some embodiments, the heat-resistant touch protective housing 28 may be omitted.

[0078] The CCU carrier 18 includes a support section 30 for supporting one end of the heat-resistant touch protective housing 28 and extending in the Z direction between the portion of the CCU carrier 18 parallel to the terminal side of the battery cell 12 and the heat-resistant touch protective housing 28. However, the battery system 100 is not limited thereto, and in some embodiments, the support section 30 may be omitted.

[0079] Figure 4 This describes the assembly according to the embodiments. Figure 1 A schematic flowchart of the method of the battery system 100 shown.

[0080] According to the first step 50, the battery pack 10 described above is provided. For example, the battery pack 10 includes a plurality of battery cells 12, each battery cell 12 having a pair of electrode terminals 14 and an exhaust valve 16 at the terminal side of the battery cell 12, the terminal side facing the first side of the battery pack 10 in the Z direction.

[0081] According to the second step 52 of the method, a CCU 32 is provided. The CCU 32 includes a CCU carrier 18 (such as the CCU carrier 18 described above) and a plurality of busbars 20 (such as the busbars 20 described above) disposed on the CCU carrier 18. Each busbar 20 includes an elastic member 22 configured to apply a clamping force to the CCU carrier 18 such that when the CCU carrier 18 is disposed on the battery pack 10, the CCU carrier 18 is pressed in the Z direction against the terminal side of each of the plurality of battery cells 12 of the battery pack 10.

[0082] According to the third step 54 of the method, the CCU carrier 18 of the CCU 32 is disposed on the terminal side of each battery cell 12 of the battery pack 10, and the busbar 20 of the CCU 32 is disposed on the electrode terminal 14 of the battery cell 12.

[0083] Some reference symbols

[0084] 10 battery packs

[0085] 12 battery cells

[0086] 14 Electrode terminals

[0087] 16. Exhaust valve

[0088] 18 Single-unit contact unit carrier; 20 Busbar

[0089] 22 Elastic Components

[0090] 24 Heat-resistant single-unit protective cover 26 CCU elastic component

[0091] 28 Heat-resistant touch protective housing; 30 Support section

[0092] 32 Single-unit contact units

[0093] 34 slots

[0094] 50 First method step 52 Second method step 54 Third method step 100 Battery system

Claims

1. A battery system, comprising: A battery pack includes multiple battery cells, each battery cell having a pair of electrode terminals and an exhaust valve at the terminal side of the battery cell, wherein the terminal side of each battery cell faces a first side of the battery pack in the Z direction; A cell contact unit (CCU) carrier is located on the terminal side of the battery cell; as well as Multiple busbars are located on the electrode terminals of the battery cells and in mechanical contact with the cell contact unit carrier. Each busbar includes an elastic member configured to apply a clamping force to the cell contact unit carrier.

2. The battery system according to claim 1, further comprising a heat-resistant cell protective cover disposed between the cell contact unit carrier and the battery cell.

3. The battery system of claim 2, wherein the elastic member of the busbar is configured to apply the clamping force on the cell contact unit carrier to press the cell contact unit carrier onto the terminal side of each of the battery cells in the Z direction via the heat-resistant cell protective cover.

4. The battery system of claim 2, wherein the cell contact unit carrier includes a cell contact unit elastic member configured to apply a cell contact unit clamping force to the heat-resistant cell protective cover to press the heat-resistant cell protective cover onto the terminal side of each of the battery cells in the Z direction.

5. The battery system according to claim 2, wherein the heat-resistant cell protective cover comprises mica and / or aerogel.

6. The battery system of claim 2, wherein the cell contact unit carrier and / or the heat-resistant cell protective cover includes recesses and / or slot-like openings disposed between adjacent cell units.

7. The battery system of claim 2, wherein the vent valve of each of the battery cells is arranged between the electrode terminals of the respective battery cell, and the dimensions of the cell contact unit carrier and / or the heat-resistant cell protective cover are configured such that the cell contact unit carrier and / or the heat-resistant cell protective cover are arranged in the region on the terminal side of the battery cell between the electrode terminals of the battery cells.

8. The battery system of claim 1, wherein when the busbar is on the electrode terminal, the elastic member of the busbar includes a spring protrusion and / or a preloaded section in the Z direction toward the battery cell.

9. The battery system of claim 1, wherein the elastic member is configured to apply a clamping force on the cell contact unit carrier sufficient to secure the cell contact unit carrier to the cell.

10. The battery system of claim 1, further comprising a heat-resistant touch protective housing mechanically bonded to the cell contact unit carrier and covering the busbar.

11. The battery system of claim 10, wherein the heat-resistant touch protective housing further partially covers the side surface of the battery cell in the Z direction to provide heat resistance between adjacent battery cells.

12. The battery system of claim 10, wherein the single-cell contact unit carrier includes a support section for supporting one end of the heat-resistant touch protective housing and extending in the Z direction between the single-cell contact unit carrier and the heat-resistant touch protective housing.

13. An electric vehicle comprising a battery system according to any one of claims 1 to 12.

14. A cell contact unit (CCU) for a battery pack, the battery pack comprising a plurality of battery cells, each battery cell having a pair of electrode terminals and an vent valve at the terminal side of the battery cell, the terminal side of each battery cell facing a first side of the battery pack in a Z direction, the cell contact unit comprising: The cell contact unit carrier on the terminal side of the battery cell; as well as Multiple busbars on the single contact unit carrier, each busbar including an elastic member configured to apply a clamping force to the single contact unit carrier.

15. A method for assembling a battery system, the method comprising: A battery pack is provided comprising a plurality of battery cells, each battery cell having a pair of electrode terminals and an exhaust valve at the terminal side of the battery cell, wherein the terminal side of each battery cell faces a first side of the battery pack in the Z direction; Provide a single contact unit as claimed in claim 14; and The carrier of the single-cell contact unit is arranged on the terminal side of each of the battery cells in the battery pack, and the busbar of the single-cell contact unit is arranged on the electrode terminal of the battery cell.

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