Battery module and method of controlling the same, and battery system and vehicle comprising the same

Abstract

The present disclosure provides a battery module, a method for controlling the same, and a battery system and a vehicle including the same. A battery module according to an embodiment is equipped with a cooling system including a plastic cooling plate, and a plastic cooling plate adjacent to a battery cell undergoing thermal runaway forms an opening to enable direct cooling by a coolant discharged through the opening, thereby enabling efficient cooling and fire suppression during thermal runaway.

Description

Technology Field

[0001] An aspect of an embodiment of the present disclosure relates to a battery module having a plastic cooling plate. Background Technology

[0002] The battery system may include a battery management system (BMS), which is an electronic system configured to manage secondary battery cells, battery modules, and battery packs, such as protecting battery cells from operating outside a safe operating area, monitoring the condition of battery cells, calculating and reporting secondary data, controlling their environment, and performing authentication and / or balancing. For example, the BMS may monitor the condition of the battery cells expressed in voltage (e.g., total voltage of the battery pack or battery module and / or voltage of individual battery cells), temperature (e.g., average temperature of the battery pack or battery module, coolant inlet temperature, coolant outlet temperature, or temperature of individual battery cells), coolant flow (e.g., flow rate and / or coolant pressure), and current. In addition, the BMS can calculate values ​​based on the above characteristics or measured values, such as minimum and maximum cell voltages, state of charge (SoC) or depth of discharge (DoD) representing the charge level of the battery cell, state of degradation (SoH; a value measured by defining the remaining capacity of the battery cell as a percentage of the initial capacity), state of power (SoP; the amount of available power for use during a defined time interval given current power consumption, temperature, and other conditions), state of safety (SoS), maximum charge current as the charge current limit value (CCL), maximum discharge current as the discharge current limit value (DCL), and the internal impedance of the battery cell (determining the open circuit voltage).

[0003] A BMS can be configured in a centralized manner, where a single controller is connected to multiple battery cells via multiple wires. Alternatively, the BMS can be configured in a distributed manner, in which case a BMS board is installed in each cell via only a single communication cable placed between the battery cell and the controller. In other cases, the BMS can be configured in a modular manner, including several controllers that handle a specific number of battery cells, along with communication between controllers. Here, the centralized BMS is the most economical and has the lowest scalability, but it involves configuration complexity due to the use of many wires. On the other hand, the distributed BMS offers simple installation and the most streamlined assembly, but is disadvantageous in terms of cost. In contrast, the modular BMS can provide a compromise between the functions and issues of the other two methods.

[0004] The BMS can protect the battery pack from operating outside the safe operating area. Operation outside the safe operating area may be indicated upon detection of overcurrent, overvoltage (during charging), overheating, low temperature, overpressure, ground fault, or leakage current. The BMS may include an internal switch (e.g., a relay or a contactless device) that opens when the battery cell operates outside the safe operating area. The BMS may prevent the battery cell from operating outside the safe operating area by operating a device connected to the battery cell (e.g., the aforementioned internal switch) to reduce or even stop the use of the battery cell, and by actively controlling the environment, such as a heater, fan, air conditioner, or liquid cooling.

[0005] An active or passive thermal management system may be included in the battery module to provide thermal control of the battery pack. This system efficiently dissipates, releases, and / or dissipates heat generated by the secondary battery, thereby enabling the safe use of the battery module. If heat dissipation, release, or dissipation is insufficient, temperature variations will occur between individual battery cells, preventing the battery module from generating the desired (or designed) power. Furthermore, if the internal temperature of a battery cell rises, abnormal reactions may occur within it, degrading the charge / discharge performance of the secondary battery and shortening its lifespan. Therefore, cooling the battery cells is crucial for effectively dissipating, releasing, and dissipating heat.

[0006] The thermal decomposition of battery cell components can lead to so-called thermal runaway. Generally, thermal runaway refers to a process of energy release that is accelerated by a rise in temperature, causing the temperature to increase further. Thermal runaway occurs when conditions are altered in such a way that a temperature increase leads to further temperature increases, often resulting in destructive consequences. In secondary battery systems, thermal runaway is associated with a strong exothermic reaction accelerated by a rise in temperature. When thermal runaway occurs, the temperature of the battery cell rises very rapidly, and stored energy is released very suddenly. In extreme cases, thermal runaway can cause the battery cell to explode and lead to a fire. Even in minor cases, thermal runaway can cause the battery cell to be damaged beyond repair.

[0007] If a battery cell is heated above a critical temperature (typically 150°C or higher), it may transition into thermal runaway. Generally, temperatures outside the lower or higher safety zones can cause irreversible damage to the battery cell and potentially trigger thermal runaway. Thermal runaway can also occur due to internal or external short circuits in the battery cell or poor battery management. For example, overcharging or rapid charging can lead to thermal runaway.

[0008] During thermal runaway, a faulty battery cell—specifically a locally failed cell—can reach temperatures exceeding 700°C. Additionally, a large volume of hot gas is ejected from inside the faulty cell into the battery pack through the exhaust port of the cell housing. The main components of the exhaust gas are H2, CO2, CO, electrolyte vapor, and other hydrocarbons. Consequently, the exhaust gas is flammable and potentially toxic. Furthermore, the exhaust gas increases the gas pressure inside the battery pack. Therefore, in the worst-case scenario, the high temperature can cause the fire to spread to adjacent cells, resulting in a fire within the battery pack, which is difficult to extinguish at this stage.

[0009] The BMS plays a crucial role in the safe operation and optimal performance of secondary battery cells and helps reduce the possibility of thermal runaway. For example, if the BMS detects that the battery cell temperature is too high, it can regulate the temperature by controlling the cooling fan. Alternatively, if the battery cell cannot be cooled or restored to safe conditions, the BMS can shut down the battery cell to protect the entire system.

[0010] Generally, cooling of battery cells is achieved by bottom cooling. For example, battery modules are designed to cool battery cells by cooling the lower side of the battery cells. In such battery modules, cell spacers are used to increase the distance between adjacent battery cells in order to prevent heat propagation. Cell spacers generally have a thickness ranging from about 3 mm to about 4 mm.

[0011] However, when using such cell spacers, the energy density of the battery module is reduced by up to about 10% compared to when they are not used. The problem to be solved

[0012] Embodiments of the present disclosure provide a battery module and a method for controlling the same that can increase the energy density of the battery module and reduce manufacturing costs.

[0013] This disclosure is defined by the appended claims and their equivalents. The following description follows these limitations. Any disclosure outside the scope of the claims and their equivalents is for illustrative and comparative purposes. means of solving the problem

[0014] A battery module according to one embodiment of the present disclosure comprises a battery cell stack including a plurality of battery cells stacked along a first direction, a plastic cooling plate configured to guide a coolant, a pump, and a controller. Each of the plurality of battery cells is in thermal contact with the plastic cooling plate, and the plastic cooling plate comprises a plastic material configured to melt when in thermal contact with a battery cell affected by thermal runaway. The controller is configured to detect a situation in which at least one of the plurality of battery cells is affected by thermal runaway, and after the thermal runaway of at least one of the plurality of battery cells is detected, to control the pump so that the coolant can be guided through the plastic cooling plate in thermal contact with at least one of the plurality of battery cells at a flow rate increased compared to the flow rate before the thermal runaway is detected.

[0015] Another embodiment of the present disclosure relates to a battery system comprising one or more battery modules described above.

[0016] Another embodiment of the present disclosure relates to a vehicle comprising at least one battery module and / or a battery system described above.

[0017] Another embodiment of the present disclosure relates to a method for controlling a battery module as described above. The control method comprises the steps of: detecting by a controller whether at least one of a plurality of battery cells is affected by thermal runaway; and, after detecting thermal runaway, controlling a pump to guide a coolant through a plastic cooling plate that is in thermal contact with at least one of the plurality of battery cells at an increased flow rate compared to the flow rate before the thermal runaway was detected.

[0018] Additional aspects and features of the present disclosure can be understood from the following description. Effects of the invention

[0019] The battery module and the control method according to the embodiment can increase the energy density of the battery module and reduce manufacturing costs. Brief explanation of the drawing

[0020] The aspects and features of the present disclosure will become apparent to those skilled in the art by describing embodiments in detail with reference to the accompanying drawings: FIG. 1 is a schematic perspective view illustrating a typical battery cell. FIG. 2 is a schematic plan view of a battery module according to one embodiment of the present disclosure. FIG. 3 is a schematic plan view of a battery module according to another embodiment of the present disclosure. FIG. 4 is a schematic cross-sectional view of a plastic cooling plate according to one embodiment of the present disclosure. FIG. 5 is a schematic cross-sectional view of a plastic cooling plate according to another embodiment of the present disclosure. FIG. 6 is a schematic plan view of a battery module according to another embodiment of the present disclosure. Specific details for implementing the invention

[0021] Embodiments of the present invention will be described in detail below with reference to the attached drawings. Effects and features according to embodiments of the present invention and methods of implementation thereof will be described below with reference to the attached drawings. However, the present invention may be implemented in various different forms and should not be interpreted as being limited to the embodiments exemplified herein. Rather, these embodiments are provided as examples to ensure that the present disclosure is thorough and complete and fully conveys the aspects and features of the present disclosure to those skilled in the art.

[0022] Accordingly, processes, elements, and technologies that are not necessary to a person skilled in the art for a full understanding of the aspects and features of the present disclosure may not be described or may be described only briefly.

[0023] As used herein, the term “and / or” includes any and all combinations of one or more associated listed items. Additionally, when describing embodiments of the present disclosure, the use of “may” means “one or more embodiments of the present disclosure.”

[0024] Terms such as “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers, and / or sections, but such elements, components, regions, layers, and / or sections should not be limited to these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Accordingly, without departing from the scope of the invention, the first component may be named the second component, and similarly, the second component may be named the first component. A single form of expression implies the inclusion of multiple components unless otherwise specified. Expressions such as “at least one” modify the entire list of components when preceding a list of components and do not modify individual elements of the list. For example, the expression “at least one of a, b, or c” indicates 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. The terms "use," "using," and "used" used herein may be considered synonyms for "utilize," "utilizing," and "utilized," respectively.

[0025] As used herein, the terms "substantially," "about," and similar terms are used as approximations rather than degrees, and are intended to describe the inherent deviation of a measured or calculated value as perceived by a person skilled in the art. Furthermore, where the term "substantially" is used in combination with a feature that can be expressed using a numerical value, the term "substantially" indicates a range of ±5% of the value centered around the value.

[0026] The term "include" or "includes" specifies characteristics, domains, fixed numbers, steps, processes, elements, components, and combinations thereof, but does not exclude other characteristics, domains, fixed numbers, steps, processes, elements, components, and combinations thereof.

[0027] Furthermore, all numerical ranges disclosed and / or described herein are intended to include all sub-ranges of the same numerical precision that are included within the described range. For example, the range “1.0 to 10.0” is intended to include all sub-ranges between (and including) the described minimum value 1.0 and the described maximum value 10.0, i.e., a range having a minimum value greater than or equal to 1.0 and less than or equal to 1.0 and a maximum value less than or equal to 10.0 (e.g., 2.4 to 7.6). All maximum numerical limits described herein are intended to include all lower numerical limits that are included therein, and all minimum numerical limits described herein are intended to include all higher numerical limits that are included therein. Accordingly, the applicant reserves the right to amend this specification, including claims, to explicitly describe all sub-ranges that are included within the ranges explicitly described herein. All such ranges are intended to be described in this specification.

[0028] In this specification, the terms top (or upper) and bottom (or lower) may be defined according to the z-axis. For example, the upper cover is located at the upper part of the z-axis, and the lower cover is located at the lower part of the z-axis. In the drawings, the size of the components may be exaggerated for clarity. For example, the size or thickness of each component in the drawings may be arbitrarily indicated for illustrative purposes, and therefore, embodiments of the invention should not be interpreted as being limited thereto.

[0029] In the following description of embodiments of the present disclosure, singular terms may include plural forms unless the context clearly indicates otherwise.

[0030] The electronic or electrical devices and / or other related devices or components according to the embodiments of the present disclosure described herein may be implemented using suitable hardware, firmware (e.g., application-specific integrated circuits), software, or a combination of software, firmware, and hardware. Additionally, various components of these devices may be implemented on flexible printed circuit films, tape carrier packages (TCPs), printed circuit boards (PCBs), or formed on a single substrate. The electrical connections or interconnections described herein may be realized by wires or conductive elements on a PCB or other types of circuit carriers. Conductive elements may include metallized elements, e.g., surface metallized elements and / or pins, and / or conductive polymers or ceramics. Additional electrical energy may be transmitted using wireless connections, e.g., electromagnetic radiation and / or light.

[0031] Additionally, various components of these devices may be processes or threads running on one or more processors, and may execute computer program instructions on one or more computing devices and interact with other system components to perform the various functions described herein. Computer program instructions are stored in memory that may be implemented in the computing device using a standard memory device, e.g., random access memory (RAM). Computer program instructions may also be stored on other non-transient computer-readable media, such as CD-ROMs, flash drives, etc.

[0032] In addition, those skilled in the art should recognize that the functions of various computing devices may be combined or integrated into a single computing device, or that the functions of a specific computing device may be distributed across one or more other computing devices without departing from the scope of the exemplary embodiments of the present disclosure.

[0033] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as generally understood by a person skilled in the art to which the present invention pertains. Furthermore, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with that meaning in the context of the relevant technology and / or this specification, and should not be interpreted in an ideal or overly formal sense.

[0034] According to one embodiment of the present disclosure, a battery module comprises a battery cell stack including a plurality of battery cells stacked along a first direction, a plastic cooling plate configured to guide a coolant, a pump, and a controller. Each of the plurality of battery cells is in thermal contact with the plastic cooling plate, and the plastic cooling plate comprises (or is made of) a plastic material configured to melt when in thermal contact with a battery cell affected by thermal runaway. The controller is configured to detect a situation in which at least one of the plurality of battery cells is affected by thermal runaway, and after thermal runaway is detected in at least one of the plurality of battery cells, the controller controls the pump to guide a coolant for the battery cell affected by thermal runaway through the plastic cooling plate in thermal contact with said battery cell, or controls the pump to increase the flow rate of the coolant guided through the plastic cooling plate in thermal contact with said battery cell compared to the flow rate before thermal runaway is detected.

[0035] In one embodiment, the controller may be configured to control the pump such that, after a thermal runaway is detected in at least one of a plurality of battery cells, the flow of the coolant guided through the plastic cooling plate is interrupted for a time interval or the flow rate of the coolant guided through the plastic cooling plate is reduced for a time interval.

[0036] In one embodiment, each of the plurality of battery cells may be prismatic. If the number of battery cell stacks is greater than one, the battery cell stacks may be arranged parallel to each other along a first direction. A plastic cooling plate may extend perpendicularly to the first direction. Each battery cell stack may be crossed (or intersected) by a plastic cooling plate.

[0037] In one embodiment, each battery cell has main sides, and at least one of the main sides can be in contact with a plastic cooling plate.

[0038] In one embodiment, each battery cell can be sandwiched between two plastic cooling plates.

[0039] In one embodiment, the battery cell stack has an even number of N battery cells grouped into N / 2 adjacent battery cell pairs, and each of the N / 2 adjacent battery cell pairs can be sandwiched between two plastic cooling plates.

[0040] In one embodiment, the plastic cooling plate may have a hollow body formed of two half plates made of a first material including plastic.

[0041] In one embodiment, two half plates each have a peripheral region and can be sealed together along their peripheral regions to form a hollow body.

[0042] In one embodiment, at least one of the two half plates may have a structure for guiding a coolant and transmitting a compressive force between the two half plates.

[0043] In one embodiment, the hollow body may include an inlay overmolded by a first material of two half plates. The inlay may include a second material different from the first material.

[0044] In one embodiment, the second material may have a higher thermal conductivity than the first material and / or the second material may have higher heat resistance than the first material.

[0045] According to another embodiment, the battery module comprises a battery cell stack including a plurality of battery cells stacked along a first direction, a plastic cooling plate configured to guide a coolant, a pump, and a controller. Each battery cell is in thermal contact with the plastic cooling plate, and the plastic cooling plate comprises (or is made of) a plastic material configured to melt upon thermal contact with a battery cell affected by thermal runaway. The controller detects a situation in which at least one of the battery cells is affected by thermal runaway, and after thermal runaway is detected in at least one battery cell, controls the pump so that for each battery cell affected by thermal runaway, a coolant is guided through the plastic cooling plate that is in thermal contact with the battery cell, or so that the flow rate of the coolant guided through the plastic cooling plate that is in thermal contact with the battery cell is increased compared to the flow rate before thermal runaway is detected.

[0046] Compared to the battery module design described in the background art of this disclosure, the battery module according to the embodiments of this disclosure offers lower cost and greater flexibility in cooler integration.

[0047] When thermal runaway occurs in one or more battery cells, the plastic cooling plate adjacent to the affected cells is heated by the heat generated within these cells due to the runaway. Since the plastic cooling plate is made of, or at least contains, a plastic material configured to melt when it comes into thermal contact with the battery cells affected by the runaway, it melts and penetrates due to the heat transferred from the adjacent cells undergoing the runaway. For example, the walls of the plastic cooling plate melt or collapse in the area adjacent to the defective battery cells. Consequently, after this process, the coolant guided through the plastic cooling plate comes into direct contact with the battery cells affected by the runaway, providing an optimal cooling effect to those cells and suppressing the thermal runaway occurring in the defective cells.

[0048] When the coolant comes into direct contact with the affected battery cell, the coolant escaping from the plastic cooling plate through the molten area may enter the interior of the battery cell, for example, through the battery cell venting opening or through an opening in the battery cell case formed due to the melting process of the battery cell caused by thermal runaway. In such cases, the interior of the affected battery cell may be flooded with the coolant.

[0049] By using plastic materials for part or all of the cooling plate, manufacturing costs are reduced compared to cooling plates typically made of metal.

[0050] In the embodiments, each plastic cooling plate is made of a plastic material configured to melt when in thermal contact with a battery cell affected by thermal runaway, or at least includes such a material.

[0051] In an example, at least one of the plastic cooling plates is made of a plastic material having a melting temperature in or below the temperature range of thermal runaway. For example, the melting temperature of the plastic material may be in a temperature range of about 150°C to about 300°C. For example, the melting temperature of the plastic material may be about 200°C.

[0052] Locally, battery cells undergoing thermal runaway can reach temperatures of up to about 1400°C. This leads to the immediate melting of the housing of the affected battery cell in the affected area (e.g., an aluminum housing with a melting temperature of about 660°C), as well as the immediate melting of the plastic material of the plastic cooling plate placed adjacent to these areas (e.g., having a melting temperature of around 200°C).

[0053] In the embodiments, part or all of the plastic cooling plate may be in direct contact with one or more surfaces of the battery cell. That is, no additional layer or coating is placed between the plastic cooling plate and the battery cell. This further enhances heat exchange between the plastic cooling plate and the battery cell.

[0054] In the embodiments, part or all of the plastic cooling plates may be attached (e.g., bonded) to each adjacent main side of the battery cell to improve the mechanical stability of the battery module. In the embodiments, a gap filler may be inserted between the main side of the battery cell and the adjacent plastic cooling plate. In these embodiments, the gap filler may also be used to attach the main side of the battery cell to the adjacent plastic cooling plate.

[0055] In an embodiment, an intermediate layer (e.g., an adhesive layer) may be provided between a plastic cooling plate and a battery cell, and the intermediate layer may be configured to melt when in thermal contact with a battery cell affected by thermal runaway.

[0056] The expression "plastic cooling plate" used in the description of this disclosure may be simply replaced with "cooling plate." However, the term "plastic cooling plate" is chosen and used to make the term easier to understand.

[0057] The term "coolant" refers to a cooling liquid such as water.

[0058] In the examples, an electrically non-conductive coolant may be used to prevent a short circuit that could occur if the coolant flows into or comes into contact with the inside of the defective battery cell after the plastic cooling plate melts in an area adjacent to the defective battery cell. However, such a short circuit does not cause significant problems. Therefore, in the examples, a conductive coolant such as water may be used. Conductive coolants such as water are generally less expensive than non-conductive coolants.

[0059] In an embodiment, the battery module includes a temperature sensor for detecting thermal runaway occurring in one or more battery cells. The temperature sensor may be attached to the battery cell. In an embodiment, one temperature sensor may be provided per battery cell. In an embodiment, the battery cells may be grouped into a group of multiple battery cells (e.g., a pair each comprising two battery cells), and one temperature sensor may be provided per group.

[0060] In an embodiment, the battery module includes a pressure sensor for detecting thermal runaway occurring in one or more battery cells. The pressure sensor may be placed inside the battery cell housing. In an embodiment, each battery cell may be equipped with a pressure sensor.

[0061] In an embodiment, the battery module includes a voltage sensor and / or a current sensor for detecting thermal runaway occurring in one or more battery cells. In an embodiment, each battery cell may be equipped with a voltage sensor and / or a current sensor.

[0062] In these embodiments, signals generated by a temperature sensor, a pressure sensor, a voltage sensor, and / or a current sensor may be transmitted to a controller, and the controller is configured to evaluate the signals and detect whether thermal runaway occurs in the battery module based on these signals.

[0063] In one embodiment of the battery module, the controller is configured to control the pump such that, after thermal runaway is detected in at least one battery cell, the flow of coolant guided through the plastic cooling plate is interrupted or reduced for a time interval.

[0064] In one embodiment of the battery module, the controller is configured to control a pump such that, after thermal runaway is detected in at least one battery cell, the flow of coolant guided through the plastic cooling plate is interrupted or reduced for a time interval for each battery cell affected by the thermal runaway and for at least one plastic cooling plate in thermal contact with the battery cell.

[0065] The effect of interrupting the flow of coolant guided through one or more plastic cooling plates in thermal contact with a battery cell affected by thermal runaway for a time interval is that the cooling effect provided to the battery cell by these plastic cooling plates is interrupted or blocked during that time interval. As a result, the plastic cooling plates in thermal contact with the battery cell affected by thermal runaway heat up more rapidly due to the heat generated by the thermal runaway in the adjacent affected battery cell, thereby accelerating the melting of the plastic material and improving the reliability of the melting effect.

[0066] However, the flow of the coolant may not be completely stopped but merely reduced. The effect of reducing the flow rate of the coolant guided through one or more plastic cooling plates in thermal contact with the battery cell affected by thermal runaway for a time interval is that the cooling effect provided to the battery cell by these plastic cooling plates is also reduced during that time interval. As a result, the plastic cooling plates in thermal contact with the battery cell affected by thermal runaway heat up more rapidly due to the heat generated by the thermal runaway in the adjacent affected battery cell, as described above, thereby accelerating the melting of the plastic material or improving the reliability of this melting effect.

[0067] The expression "after detection" in the present disclosure may be understood as "immediately after the point of detection or after a specific (e.g., predefined) time interval has elapsed after detection."

[0068] In one embodiment of the battery module, each battery cell is prismatic, and the battery cells are arranged in at least one battery cell stack.

[0069] In one embodiment of the battery module, when the number of battery cell stacks is greater than one, the battery cell stacks are arranged parallel to each other along a first direction, each plastic cooling plate extends in a direction perpendicular to the first direction, and each battery cell stack is crossed (or intersected) by at least one plastic cooling plate.

[0070] According to the embodiments described above, since each plastic cooling plate extends in a direction perpendicular to the first direction, the plastic cooling plates are all arranged parallel to each other.

[0071] In one embodiment of the battery module, each battery cell includes main sides, at least one of the main sides contacts at least one of the plastic cooling plates.

[0072] Compared to the bottom-cooling battery module design described in the background art of the present disclosure, the above-described embodiments can provide a cooling area increased by up to 10 times.

[0073] In addition, expensive cell spacers inserted between battery cells can be omitted.

[0074] Depending on the geometry of the stack, when one of the battery cell stacks is viewed along its length, between any two adjacent plastic cooling plates, a single battery cell of the said battery cell stack may be sandwiched between these two adjacent plastic cooling plates (in which case, either of the main sides of the said battery cell may be cooled by the plastic cooling plates), or an adjacent pair of battery cells of the said battery cell stack may be sandwiched between these two adjacent plastic cooling plates (in which case, for each of these battery cells, only one of the main sides may be cooled by the plastic cooling plates).

[0075] In one embodiment of the battery module, each battery cell is sandwiched between two plastic cooling plates.

[0076] In one embodiment of the battery module, each battery cell stack comprises an even number of N battery cells grouped into N / 2 adjacent battery cell pairs, and each of the N / 2 adjacent battery cell pairs is sandwiched between two plastic cooling plates.

[0077] In one embodiment of the battery module, each plastic cooling plate crosses or intersects each of the battery cell stacks.

[0078] In one embodiment, the battery module further includes an inlet channel and an outlet channel, wherein the inlet channel is fluidly connected to each plastic cooling plate and the outlet channel is fluidly connected to each plastic cooling plate.

[0079] Here, the term "fluidically connected" refers to a connection between two pipes or channels that facilitates the smooth exchange of fluid while ensuring that flow and communication are not interrupted.

[0080] In the above-described embodiment, the inlet channel and the outlet channel may be positioned so that each battery cell stack is placed between the inlet channel and the outlet channel. Then, the flow of coolant from the inlet channel through the plastic cooling plate to the outlet channel will cross each battery cell stack, thereby providing an excellent cooling effect to each battery cell stack.

[0081] An inlet channel may be fluidly connected to a first reservoir that provides "fresh" coolant, that is, coolant having a temperature suitable for cooling the battery cell (e.g., a temperature in the range of about -40°C to about +55°C). An outlet channel may be fluidly connected to a second reservoir from which used coolant (e.g., coolant that has flowed through a plastic cooling plate) can be discharged. The coolant discharged into the second reservoir may be cooled by a cooling device, transferred back to the first reservoir, and then used again as "fresh" coolant.

[0082] To move "fresh" coolant into the inlet channel, a pump may be placed between the first reservoir and the inlet of the inlet channel. Alternatively, or additionally, another pump may be placed between the outlet of the outlet channel and the second reservoir to discharge the used coolant out of the outlet channel.

[0083] In another embodiment, only a single reservoir may be used, from which coolant may be supplied to an inlet channel and discharged to this reservoir from an outlet channel. In this embodiment, the single reservoir may be cooled by a cooling device.

[0084] In another embodiment of the battery module, the first and second reservoirs may be omitted. This is because, in the event of thermal runaway of a single battery cell or a specific group of battery cells, the body of the remaining battery module (including the battery cells not affected by the thermal runaway) usually exhibits a very large thermal mass, so the coolant circulating within the cooling system of the battery module is usually sufficient to cool the affected battery cells.

[0085] In one embodiment of the battery module, at least one plastic cooling plate comprises a hollow body assembled from two half plates comprising a first material including plastic.

[0086] In the example, the material of the half plate is plastic material.

[0087] In the example, each plastic cooling plate includes a hollow body assembled from two half plates.

[0088] All or at least one of the half plates may be designed in a substantially flat plate shape having a concave (or depression) (forming a major part of the half plate) and a peripheral area surrounding the concave (e.g., extending around the concave).

[0089] In one embodiment of the battery module, two half plates each include a peripheral region and are sealed together along their peripheral regions.

[0090] In the embodiment, for every body of the plastic cooling plate, two half plates each include a peripheral region and can be sealed together along their peripheral regions.

[0091] In an embodiment, for at least one of the main bodies of the plastic cooling plate, two half plates may be sealed to each other by hot-plate welding. In one or more embodiments, for each main body of the plastic cooling plate, two half plates may be sealed to each other by hot-plate welding.

[0092] In one embodiment of the battery module, regarding at least one of the main bodies of the plastic cooling plates, at least one of the two half plates includes a structure for guiding a coolant and transmitting a compressive force between the two half plates.

[0093] These compressive forces, also referred to as swelling forces, can occur when the battery cell swells during use.

[0094] The above-described structure transmits compressive force between two half plates, thereby transmitting compressive force between both sides of a plastic cooling plate including a main body.

[0095] In one embodiment of the battery module, at least one of the bodies of the plastic cooling plate comprises an inlay overmolded by a first material of the half plate. The inlay comprises a second material different from the first material.

[0096] The second material may be a plastic material or may include a plastic material.

[0097] In one embodiment of the battery module, the second material has a higher thermal conductivity than the first material and / or the second material has higher heat resistance than the first material.

[0098] In an embodiment where the second material has higher heat resistance than the first material, the second material may include mica or glass fiber.

[0099] According to an embodiment of the present disclosure, a cooling effect can be enhanced when thermal runaway occurs in one or more battery cells. When thermal runaway occurs in one or more battery cells, a controller (which may be integrated into a BMS) activates a cooling system. This initiates cooling of the battery cells affected by the thermal runaway, and additionally, adjacent battery cells can also be cooled and protected.

[0100] In the case of a plastic cooling plate, if the area adjacent to the battery cell undergoing thermal runaway melts locally, a coolant (e.g., coolant) is poured directly onto the very hot surface adjacent to the battery cell, which provides very intensive and effective cooling.

[0101] Another embodiment of the present disclosure relates to a battery system comprising one or more battery modules described above.

[0102] Another embodiment of the present disclosure relates to a vehicle comprising at least one battery module and / or at least one battery system described above.

[0103] The vehicle can be a hybrid vehicle or a pure electric vehicle.

[0104] Another embodiment of the present disclosure relates to a method for controlling the battery module described above. The control method comprises the steps of: detecting, by means of a controller, whether at least one of a plurality of battery cells is affected by thermal runaway; and, after detecting thermal runaway, removing a pump so that a coolant is guided through a plastic cooling plate that is in thermal contact with the battery cell affected by thermal runaway, or controlling a pump so that the flow rate of the coolant guided through the plastic cooling plate that is in thermal contact with the battery cell is increased compared to the flow rate before the thermal runaway is detected.

[0105] In one embodiment, the control method further comprises the step of controlling the pump such that, before detecting thermal runaway and controlling the pump, the flow of coolant guided through a plastic cooling plate is interrupted for a time interval or the flow rate of coolant guided through the plastic cooling plate is reduced for a time interval. Another embodiment of the present disclosure relates to a method for controlling a battery module comprising the steps of: detecting, by a controller, whether at least one of the battery cells is affected by thermal runaway; and, after detecting thermal runaway, controlling the pump such that, for each battery cell affected by thermal runaway, the coolant is guided through at least one of the plastic cooling plates that is in thermal contact with the battery cell, or the flow rate of coolant guided through the plastic cooling plate is increased compared to the flow rate before the thermal runaway is detected.

[0106] In one embodiment, the control method further includes the step of controlling the pump such that, before detecting thermal runaway and controlling the pump, the flow of the coolant guided through the plastic cooling plate is interrupted for a time interval or the flow rate of the coolant guided through the plastic cooling plate is reduced for a time interval.

[0107] In one embodiment, the control method further includes the step of, before detecting thermal runaway and controlling the pump, controlling the pump such that for each battery cell affected by thermal runaway, the flow of coolant guided through the plastic cooling plate is interrupted for a time interval or the flow rate of coolant guided through the plastic cooling plate is reduced for a time interval for at least one plastic cooling plate that is thermally in contact with the battery cell.

[0108] The effect of interrupting or reducing the flow of a coolant guided through one or more plastic cooling plates in thermal contact with a battery cell affected by thermal runaway for a time interval has already been described above, and the description applies correspondingly to the embodiment regarding the control method of the battery module.

[0109] A battery module or battery system generally comprises one or more battery cell stacks. Individual battery cells in a battery cell stack generally have the same or substantially the same shape as each other. For example, a typical battery cell (1) used in a battery cell stack is schematically illustrated in FIG. 1. The illustrated battery cell (1) has a parallelepiped (e.g., angular) shape defined substantially by a case (1'). The case (1') is a hard case that may be made of, for example, a metal material. The case (1') may have a can shape or a barrel shape that includes six outer faces that are substantially flat. The case (1') in FIG. 1 includes a pair of congruent main sides facing each other (in FIG. 1, only the main side (14) facing the x-direction of this pair is shown). Each main side may be positioned perpendicular to the x-axis. Additionally, the case (1') includes a lower side (not shown in FIG. 1) and an upper side (16). The lower side and the upper side (16) are congruent and positioned opposite each other, and each of the lower side and the upper side (16) can be positioned perpendicular to the z-axis. Additionally, the case (1') includes a pair of congruent sides positioned opposite each other (in FIG. 1, only the side (11) facing in the y-direction of this pair is shown). Each side can be positioned perpendicular to the y-axis. As can be seen from FIG. 1, the main side of the battery cell (1) may be the side of the case (1') having the largest surface area.

[0110] A first terminal (T1) and a second terminal (T2) are disposed on the upper side (16) of the battery cell (1). Accordingly, the upper side (16) may be referred to as the "terminal side (or terminal side)" of the battery cell (1). The terminals (T1, T2) enable electrical connection (e.g., external electrical connection) of the battery cell (1). The first terminal (T1) may be the positive terminal of the battery cell (1), and the second terminal (T2) may be the negative terminal of the battery cell (1). However, conversely, the first terminal may be the negative terminal of the battery cell and the second terminal may be the positive terminal of the battery cell. A venting outlet (V) is disposed on the upper side (16) between the first terminal (T1) and the second terminal (T2). In the event of a thermal event, such as thermal runaway, occurring in the battery cell (1), venting gas may be discharged from the battery cell (1) through the venting outlet (V). A venting valve may be installed above the venting outlet (V) from inside the battery cell (1). The venting valve is configured to open (e.g., burst) when the gas pressure inside the battery cell exceeds a reference (or predefined) value, and otherwise, to remain closed when, for example, the gas pressure inside the battery cell is below the reference value. Thus, the venting gas may pass through the venting valve placed inside the battery cell (1) before being discharged (or output) through the venting outlet (V).

[0111] A stack of battery cells (hereinafter referred to as a “battery cell stack” or simply “stack”) may be formed by stacking together a plurality of battery cells designed identically (or similarly) to the battery cell (1) shown in FIG. 1 along a first direction. The first direction (hereinafter referred to as the “stacking direction”) may be, for example, a direction parallel to the x-axis of the coordinate system shown in FIG. 1. Any one of the individual battery cells (1) may be arranged within the stack so as to extend perpendicularly to its main side x-axis. Generally, a battery module uses or includes a plurality of battery cell stacks. In a battery cell stack, adjacent battery cells may be in direct contact with each other or spaced apart from each other by cell spacers. Cell spacers may be used or included to control the overall length of the stack. Additionally, cell spacers (also referred to as “gap fillers”) may be configured to suppress or at least reduce heat propagation along the stack (e.g., between battery cells within the stack) in consideration of the heat generated during thermal runaway. One or more cell spacers may be coupled to or included in the battery cell stack.

[0112] FIG. 2 is a schematic plan view illustrating a battery module (10) according to one embodiment of the present disclosure. The battery module (10) illustrated in FIG. 2 comprises, for example, four battery cell stacks (10a, 10b, 10c, 10d). Each stack comprises, for example, eight battery cells. For example, the first battery cell stack (10a) comprises battery cells (1a1, 1a2, ..., 1a8) aligned along the x-direction. The second stack (10b), the third stack (10c), and the fourth stack (10d) also have a similar arrangement of battery cells. For clarity of the drawing, only the first, second, and last battery cells of each stack are referenced in FIG. 2. Each battery cell (1a1, 1a2, ..., 1a8, 1b1, 1b2, ..., 1b8, 1c1, 1c2, ..., 1c8, 1d1, 1d2, ..., 1d8) may have a design similar to the battery cell (1) shown in FIG. 1 and includes a first terminal (T1) and a second terminal (T2). A venting outlet (V) is not shown in FIG. 2 for the sake of simplification of the drawing. Additionally, a controller, a temperature sensor, and a pump that may be included in the battery module (10) are omitted from FIG. 2 for the sake of brevity of the drawing. The operation of the controller, the temperature sensor, and the pump will be described later with reference to FIG. 6.

[0113] The battery module (10) according to the embodiment illustrated in FIG. 2 further comprises a cooling system including a plurality of cooling plates (P1, P2, P3, P4, P5, P6, P7, P8, P9) as well as an inlet channel (C1) and an outlet channel (C2). Each of the cooling plates (P1, ..., P9) has a hollow body that extends parallel to the yz plane of a coordinate system perpendicular to the x-axis, that is, perpendicular to the stacking direction (x) of each stack (10a, 10b, 10c, 10d). Additionally, the body of each cooling plate (P1, ..., P9) is made of a plastic material having a melting point in a temperature range (e.g., a temperature range of about 400°C to about 1400°C) or lower than that of a battery cell that generally undergoes thermal runaway. For example, the melting point of the plastic material may be in a temperature range of about 150°C to about 300°C. For example, the melting point of the plastic material may be a temperature of about 200°C. Hereinafter, the cooling plates (P1, ..., P9) may be referred to as "plastic cooling plates". The design of the plastic cooling plates (P1, ..., P9) will be described in more detail below with reference to FIGS. 4 and FIGS. 5.

[0114] The inlet channel (C1) and the outlet channel (C2) can both be formed as pipes that fluidly communicate with each of the plastic cooling plates (P1, ..., P9). The inlet channel (C1) includes an inlet (I) that can be connected to a first reservoir (or reservoir) providing "fresh" coolant, i.e., coolant having a temperature suitable for cooling the battery cell. For example, the "fresh" coolant may have a temperature in the range of about -40°C to about +55°C. Additionally, the outlet channel (C2) includes an outlet (O) that can be connected to a second reservoir (or reservoir) from which used coolant (e.g., coolant that has flowed through the plastic cooling plates) can be discharged. The coolant discharged to the second reservoir can be cooled and transferred to the first reservoir and then (re)used again as "fresh" coolant. To move the "fresh" coolant to the inlet channel (see arrow F1 in FIG. 2), a pump may be placed between the first reservoir and the inlet (I). Alternatively or additionally, a pump may be placed between the outlet (O) and the second reservoir to discharge the used coolant out of the outlet channel (see arrow F2 in FIG. 2).

[0115] Since each plastic cooling plate (P1, ..., P9) is fluidly connected to the inlet channel (C1) as well as the outlet channel (C2), the coolant can be guided through each of the plastic cooling plates (P1, ..., P9).

[0116] In the embodiment of the battery module shown in FIG. 2, the arrangement of battery cells (1a1, ..., 1a8, 1b1, ..., 1b8, 1c1, ..., 1c8, 1d1, ..., 1d8) on plastic cooling plates (P1, ..., P9) can be described as follows.

[0117] When viewed along the x direction, the first plastic cooling plate (P1) is positioned in front of the first battery cell (1a1, 1b1, 1c1, 1d1) of each battery cell stack (10a, 10b, 10c, 10d) and extends parallel to the yz plane of the coordinate system (e.g., perpendicular to the drawing plane of FIG. 2). Accordingly, each main side of the first battery cell (1a1, 1b1, 1c1, 1d1) facing the first plastic cooling plate (P1) is in contact with the first plastic cooling plate (P1) and is completely covered by the first plastic cooling plate (P1) or at least its main part is covered.

[0118] Similarly, when viewed along the x direction, the last plastic cooling plate (P9) is positioned behind the last battery cell (1a8, 1b8, 1c8, 1d8) of each battery cell stack (10a, 10b, 10c, 10d) and extends parallel to the yz plane of the coordinate system. Accordingly, each main side of the last battery cell (1a8, 1b8, 1c8, 1d8) facing the last plastic cooling plate (P9) is in contact with the last plastic cooling plate (P9) and is completely covered by the last plastic cooling plate (P9) or at least its main part is covered.

[0119] Since each battery cell stack (10a, 10b, 10c, 10d) is defined in the x-direction by a first plastic cooling plate (P1) and a last plastic cooling plate (P9), these two plastic cooling plates (P1, P9) may be referred to as "outer (or external) plastic cooling plates" below. In contrast, each of the remaining plastic cooling plates (P2, P3, P4, P5, P6, P7) may be referred to as "inner (or internal) plastic cooling plates."

[0120] Any of the inner plastic cooling plates (P2, P3, P4, P5, P6, P7) cross or intersect each of the four battery cell stacks (10a, 10b, 10c, 10d). For each stack (10a, 10b, 10c, 10d), for example, the second plastic cooling plate (P2) is positioned between the first and second battery cells of the corresponding stack when viewed along the x direction. For instance, in the first battery cell stack (10a), the second plastic cooling plate (P2) is positioned between the first battery cell (1a1) and the second battery cell (1a2) of the first battery cell stack (10a) when viewed along the x direction. This arrangement is applied in the same way to the remaining stacks (10b, 10c, 10d). Additionally, the second plastic cooling plate (P2) extends parallel to the yz plane of the coordinate system. Accordingly, the second plastic cooling plate (P2) contacts not only one main side facing the x direction of the first battery cell (1a1, 1b1, 1c1, 1d1) of the stack (10a, 10b, 10c, 10d), but also one main side facing the opposite x direction of the second battery cell (1a2, 1b2, 1c2, 1d2) of the stack (10a, 10b, 10c, 10d). Accordingly, each of the two main sides is completely covered by the second plastic cooling plate (P2), or at least its main portion is covered. The remaining inner plastic cooling plates (P3, P4, P5, P6, P7) are also arranged in this manner.

[0121] In the above-described embodiment, individual battery cells (1a1, ..., 1a8Each of the plastic cooling plates (P1, P2, P3, P4, P5, P6, P7, P8, P9) is sandwiched between two adjacent (or neighboring) plastic cooling plates as shown in FIG. 2. Thus, each of the plastic cooling plates (P1, P2, P3, P4, P5, P6, P7, P8, P9) is in contact with the main side of an individual battery cell (e.g., the side with the widest surface or surface area). Thus, when the coolant is guided through the plastic cooling plates (P1, ..., P9), optimal heat exchange occurs between the coolant and each battery cell. In this embodiment, the plastic cooling plates (P1, ..., P9) may be in direct contact with the main side of the battery cell (e.g., in some embodiments, there is no additional layer or coating between the plastic cooling plates and the battery cell except for an adhesive layer), thereby further enhancing the heat exchange between them. On the other hand, to improve the mechanical stability of the battery module (10), plastic cooling plates (P1, ..., P9) may be attached (e.g., bonded) to each adjacent main side of the battery cell. In another embodiment, a gap filler may be inserted between the main side of the battery cell and the adjacent plastic cooling plate. In this embodiment, the gap filler may be used to attach the main side of the battery cell to the adjacent plastic cooling plate.

[0122] The material of the plastic cooling plates (P1, ..., P9) is optimized to have sufficient thermal conductivity. Heat dissipation from the battery cell can be enhanced through the plastic material having excellent thermal conductivity and increased surface contact between the cooling plates and the main side of the battery cell.

[0123] The gap filler is approximately 0.6 Wm -1 K -1It can have a thermal conductivity. When the thickness of the plastic cooling plate is 1.5 mm, it is necessary to maintain the same conductivity (e.g., thermal conductivity) across the entire area of ​​the plastic cooling plate that is in thermal contact with the battery cell. Therefore, it is necessary to reduce or minimize the thickness of the plastic cooling plate, which means reducing the amount of thermally conductive plastic material required.

[0124] FIG. 3 is a plan view of a battery module (10') according to another embodiment of the present disclosure. Except for the space required for a plastic cooling plate, the arrangement of battery cells (1a1, 1a2, 1a3, 1a4, 1a5, 1a6, 1a7, 1a8, 1b1, 1b2, 1b3, 1b4, 1b5, 1b6, 1b7, 1b8, 1c1, 1c2, 1c3, 1c4, 1c5, 1c6, 1c7, 1c8, 1d1, 1d2, 1d3, 1d4, 1d5, 1d6, 1d7, 1d8) in this embodiment is similar to the embodiment of FIG. 2. The battery module (10') of this embodiment includes four battery cell stacks (10a, 10b, 10c, 10d). Each stack (10a, 10b, 10c, 10d) contains eight battery cells aligned along the x-direction. Each battery cell (1a1, ..., 1d8) may have a design similar to the battery cell (1) shown in FIG. 1. As with FIG. 2, the venting outlet (V) in FIG. 3 is not shown for the sake of drawing simplification. Additionally, the controller, temperature sensor, and pump that may be included in the battery module (10') are also omitted for the sake of drawing simplification. The functions of the controller, temperature sensor, and pump will be described later with reference to FIG. 6.

[0125] The battery module (10') illustrated in FIG. 3 further includes a cooling system comprising a plurality of plastic cooling plates (P1, P2, P3, P4, P5) as well as an inlet channel (C1) and an outlet channel (C2). The appearance of the plastic cooling plates (P1, ..., P5) and the channels (C1, C2) corresponds to that described through FIG. 2. Additionally, elements for guiding the coolant through the plastic cooling plates (P1, ..., P5) and the channels (C1, C2) may include one or more pumps and reservoirs as described through FIG. 2. More details regarding the design of the plastic cooling plates (P1, ..., P5) will be described later with reference to FIG. 4 and FIG. 5.

[0126] Unlike the embodiment of FIG. 2, the battery module (10') illustrated in FIG. 3 includes a smaller number (e.g., 5) of plastic cooling plates (P1, ..., P5). When viewed along the x-direction, the first plastic cooling plate (P1) is positioned in front of the first battery cell (1a1, 1b1, 1c1, 1d1) of each battery cell stack (10a, 10b, 10c, 10d). The first plastic cooling plate (P1) extends parallel to the yz plane of the coordinate system (e.g., perpendicular to the drawing plane of FIG. 3). Accordingly, the first plastic cooling plate (P1) completely covers or at least covers a major part of each of the major sides of the first battery cells (1a1, 1b1, 1c1, 1d1), while in contact with the major side facing the x-direction.

[0127] Similarly, when viewed along the x direction, the last plastic cooling plate (P5) is positioned behind the last battery cell (1a8, 1b8, 1c8, 1d8) of each battery cell stack (10a, 10b, 10c, 10d). The last plastic cooling plate (P5) extends parallel to the yz plane of the coordinate system. Accordingly, the last plastic cooling plate (P5) contacts the main side of the last battery cell (1a8, 1b8, 1c8, 1d8) facing the x direction, thereby completely covering the main side of the last battery cell (1a8, 1b8, 1c8, 1d8) or at least covering a major part thereof.

[0128] Since each of the battery cell stacks (10a, 10b, 10c, 10d) of this embodiment is also defined by the first plastic cooling plate (P1) and the last plastic cooling plate (P5) in the x direction, these two plastic cooling plates (P1, P5) may be referred to as "outer (or external) plastic cooling plates." Likewise, each of the remaining plastic cooling plates (P2, P3, P4) may be referred to as "inner (or internal) plastic cooling plates."

[0129] In each battery cell stack (10a, 10b, 10c, 10d), each of the eight individual battery cells is grouped into pairs of adjacent (or neighboring) battery cells. For example, the battery cells (1a1, 1a2, ..., 1a8) of the first stack (10a) are grouped into a first pair comprising the first and second battery cells (1a1, 1a2), a second pair comprising the third and fourth battery cells (1a3, 1a4), a third pair comprising the fifth and sixth battery cells (1a5, 1a6), and a fourth pair comprising the seventh and eighth battery cells (1a7, 1a8). The battery cells of the remaining stacks (10b, 10c, 10d) may also be grouped in a corresponding manner as shown in FIG. 3.

[0130] In such a pair of battery cells, both battery cells are separated by a cell spacer (70) for electrical insulation. The cell spacer (70) may be relatively thin. Additionally, the cell spacer (70) may be designed to compensate for tolerances and accumulated swelling forces, respectively.

[0131] In the embodiment illustrated in FIG. 3, the inner plastic cooling plates are arranged so that each of the aforementioned pairs of battery cells in each stack (10a, 10b, 10c, 10d) is sandwiched between two plastic cooling plates. For example, each first pair of battery cell stacks (10a, 10b, 10c, 10d) is sandwiched between a first plastic cooling plate (P1) and a second plastic cooling plate (P2). Similarly, each second pair of battery cell stacks (10a, 10b, 10c, 10d) is sandwiched between a second plastic cooling plate (P2) and a third plastic cooling plate (P3). Additionally, each third pair of battery cell stacks (10a, 10b, 10c, 10d) is sandwiched between a third plastic cooling plate (P3) and a fourth plastic cooling plate (P4). Finally, each fourth pair of battery cell stacks (10a, 10b, 10c, 10d) is sandwiched between the fourth plastic cooling plate (P4) and the fifth (e.g., last) plastic cooling plate (P5).

[0132] Accordingly, unlike the embodiment of FIG. 2, where both main sides of each battery cell are in thermal contact with the plastic cooling plate, in the embodiment of FIG. 3, only one of the main sides of each battery cell is in thermal contact with the plastic cooling plate. This allows for the use of a plastic cooling plate with an increased thickness (e.g., double the thickness) compared to the embodiment of FIG. 2 within the same packaging space provided by the embodiment shown in FIG. 2. To achieve a packaging ratio similar to a design using cell spacers with a thickness in the range of about 3 mm to about 4 mm, the embodiment of FIG. 3 can increase the wall thickness of the plastic cooling plate.

[0133] The embodiment of FIG. 2 illustrates a concept in which both main sides of each battery cell are in thermal contact with a plastic cooling plate. On the other hand, the embodiment of FIG. 3 illustrates a concept in which only one main side of each battery cell is in thermal contact with a plastic cooling plate, but a plastic cooling plate having a thicker wall compared to the embodiment of FIG. 2 can be used.

[0134] Although each embodiment of FIGS. 2 and 3 is described as including 8 battery cells per stack, aspects and features of the present disclosure can be generalized to use N battery cells per stack. Here, N is any natural number according to the embodiment of FIG. 2 and an even natural number according to the embodiment of FIG. 3. Of course, the number of battery cell stacks used may also be changed. Here, the term "natural number" means a set of positive integers.

[0135] For example, when the battery module (10) of the embodiment of FIG. 2 is configured with N battery cells, two outer plastic cooling plates are included. That is, when viewed along the stacking direction, a first plastic cooling plate is placed in front of each first battery cell of the battery cell stack (e.g., on the front), and a last plastic cooling plate is placed behind each last battery cell of the battery cell stack when viewed along the stacking direction. Additionally, since a plastic cooling plate is provided between any two adjacent battery cells of each stack, (N - 1) inner plastic cooling plates are included. Thus, according to the embodiment of FIG. 2, a total of (N + 1) plastic cooling plates are included.

[0136] Additionally, when the battery module (10') of the embodiment of FIG. 3 is configured with N battery cells (N is an even natural number), two outer plastic cooling plates are included. That is, when viewed along the stacking direction, a first plastic cooling plate is placed in front of each first battery cell of the battery cell stack (e.g., on the front), and a last plastic cooling plate is placed behind each last battery cell of the battery cell stack when viewed along the stacking direction. Additionally, since plastic cooling plates are provided between any two adjacent pairs of battery cells in each stack, (N / 2 - 1) inner plastic cooling plates are included. Thus, according to the embodiment illustrated in FIG. 3, a total of (N / 2 + 1) plastic cooling plates are included.

[0137] A plastic cooling plate can be described through FIGS. 4 and 5, and the plastic cooling plate accordingly can be used in the aforementioned embodiment and in a generalized embodiment having N battery cells per stack described above. Accordingly, the plastic cooling plate (200) schematically illustrated in FIGS. 4 and 5 can be adopted as any one of the plastic cooling plates (P1, P2, P3, P4, P5, P6, P7, P8, P9) of the battery module (10) described with reference to FIG. 2, or as any one of the plastic cooling plates (P1, P2, P3, P4, P5) of the battery module (10') described with reference to FIG. 3.

[0138] As schematically illustrated in FIG. 4, the plastic cooling plate (200) may include a first half plate (210) and a second half plate (220). FIG. 4 (A) shows a schematic cross-section of the plastic cooling plate (200) in an unassembled state, while FIG. 4 (B) shows a schematic cross-section of the same plastic cooling plate (200) in an assembled state. In the embodiment of FIG. 4, the first half plate (210) and the second half plate (220) are formed symmetrically. For example, the shape of the second half plate (220) can be obtained by mirroring the shape of the first half plate (210) with respect to a plane parallel to the yz plane of the coordinate system. In various embodiments, the first half plate (210) and the second half plate (220) may be shaped identically. For example, referring to (A) of FIG. 4, the shape of the second half plate (220) can be obtained by rotating the shape of the first half plate (210) by an angle of 180° around an axis parallel to the y-axis of the coordinate system (e.g., perpendicular to the drawing plane of FIG. 4).

[0139] Due to this symmetry, details regarding the half plates are described with reference to the first half plate (210), and it should be understood that the same description may also apply to the second half plate (220). The first half plate (210) comprises a substantially flat plate shape having a concave (or sunken) portion (211) and a peripheral area (212) surrounding (e.g. extending around) the concave portion (211). With respect to the coordinate system of FIG. 4, the concave portion (211) is convex in the direction opposite to the x-axis within the first half plate (210). The portion of the second half plate (220) corresponding to this portion of the first half plate (210) is indicated by adding a prime to the same reference numeral. In FIG. 4 (A), the upper part (212a, 212a') and the lower part (212b, 212b') of the peripheral region (212, 212') appear separated from each other, but the upper part (212a, 212a') and the lower part (212b, 212b') are joined together at the lower and upper parts of the first and second half plates (210, 220) to form a continuous circumferential peripheral region (212) of the first and second half plates (210, 22).

[0140] Additionally, the first half plate (210) includes a plurality of noses (e.g., protrusions) (214). Each nose (214) has a structure protruding in the x-direction from a recess (211). When the first half plate (210) is assembled with the second half plate (220) to form a plastic cooling plate as illustrated in (B) of FIG. 4, the noses (214) of the first half plate (210) come into contact with each nose (214') of the second half plate (220) to form a bridge (214a). This bridge (214a) can form a structure for guiding the coolant flowing within the cavity (201) of the plastic cooling plate (200). Additionally, or alternatively, the bridge (214a) can form a structure for transmitting compressive force between the two half plates. The compressive force may be a swelling force generated by a battery cell case (1') that expands while using a battery cell placed adjacent to a plastic cooling plate (200) in a battery module according to an embodiment of the present disclosure. The bridge (214a) may be designed to have rigidity to provide optimal battery cell life performance and, furthermore, may also serve as a tolerance compensation for thickness variation of the battery cell. The nose (214, 214') and / or the bridge (214a) may be made of a plastic material.

[0141] In another embodiment, the nose may be omitted from the second half plate (220), whereas the nose (214) of the first half plate (210) may be formed long to form a complete (or whole) bridge (214a) when the first half plate (210) and the second half plate (220) are assembled into a plastic cooling plate (200), as shown in (B) of FIG. 4. In some embodiments, some bridges (214a) may be formed integrally by the nose protruding from the first half plate (210), while other bridges (214a) may be formed integrally by the nose protruding from the second half plate (220). In the above-described embodiment, the first half plate (210) and the second half plate (220) may no longer be configured symmetrically due to the noses.

[0142] The bridge (214a) may be formed as a column extending in the x direction between the concave portion (211) of the first half plate (210) and the concave portion (211') of the second half plate (220). In another embodiment, the bridge (214a) may be formed as a fin forming a flat structure extending in the x direction between the concave portion (211) of the first half plate (210) and the concave portion (211') of the second half plate (220), each extending parallel or substantially parallel to the xy plane of the coordinate system.

[0143] When the first half plate (210) and the second half plate (220) exemplified in FIG. 4 (A) are assembled to form the plastic cooling plate (200) illustrated in FIG. 4 (B), the first half plate (210) and the second half plate (220) are attached to each other by (or along) their peripheral regions (212, 212'). In the assembled plastic cooling plate (200), the recess (211) of the first half plate (210) and the corresponding recess (211') of the second half plate (220) face in opposite directions. As a result, a cavity (201) is formed in the recess (211, 211') region between the first half plate (210) and the second half plate (220).

[0144] To assemble the plastic cooling plate (200), the first half plate (210) and the second half plate (220) may be welded together, for example, by hot plate welding or mirror welding. In the example illustrated in FIG. 4, the first half plate (210) and the second half plate (220) are welded together in (or along) their peripheral regions (212, 212'). For example, the welding is performed through a welding line (216) that runs along the peripheral regions (212, 212') of the first and second half plates (210, 220). Accordingly, the recess (211) of the first half plate (210) as well as the recess (211') of the second half plate (220) (see FIG. 5) and the cavity (201) formed between the first and second half plates (210, 220) as described above are completely enclosed. In other words, the cavity (201) forming the interior of the plastic cooling plate (200) is sealed in a liquid-sealed manner by a welding line (216) connecting the first and second half plates (210, 220).

[0145] The first half plate (210) and the second half plate (220) in a welded state as shown in (B) of FIG. 4 form the body of the plastic cooling plate (200). In the y-direction, this body is positioned across all battery stacks of the battery module according to the embodiment of the present disclosure, for example, the battery cell stacks (10a, 10b, 10c, 10d) of the embodiment shown in FIG. 2 or FIG. 3, or in front of or behind them, and may have a width sufficiently large to cover the main side of each adjacent battery cell when implemented in the battery module. Additionally, in the z-direction, the body may have a height corresponding to (e.g., exactly or approximately) or greater than the height of the case (1') of the battery cell used in the battery module (10, 10'). Consequently, in the general case where the battery module includes one or more battery cell stacks, the body may have an elongated shape parallel to the yz plane, for example, as illustrated in FIG. 5, where the degree of elongation along the y direction is greater than the degree of elongation along the z direction. Through various embodiments, the body exemplified in (B) of FIG. 4 may be supplemented by additional configurations described below, which will be explained with reference to FIG. 5.

[0146] Depending on the desired (or designed) cooling performance of the plastic cooling plate (200), a member having a higher thermal conductivity may be placed as an inlay (240) in the injection molding of the first half plate (210) and the second half plate (220). The inlay (240) may be made of plastic material. The inlay (240) provides a surface having a relatively high thermal conductivity in major contact areas such as the concave (211, 211') region, while allowing the use of low-cost plastic in other areas of the plastic cooling plate (200). As described with reference to FIGS. 2 and 3, when the plastic cooling plate (200) is implemented in a battery module (10, 10'), the inlay (240) may be configured to remain stable despite high temperatures to ensure higher temperature stability in the event of thermal runaway of one or more adjacent battery cells. In addition, a material having higher temperature stability (or higher heat resistance) than the plastic material of the main body, such as mica or glass fiber mat, can be overmolded into a major area such as the concave area (211, 211').

[0147] As previously described with reference to FIGS. 2 and 3, the plastic cooling plate (200) is configured to be fluidly connected to the inlet channel (C1) and the outlet channel (C2) of the battery module (10, 10'), respectively. The inlet channel (C1) and the outlet channel (C2) may pass through the periphery of the cavity (201) of the plastic cooling plate (200), respectively. Thus, the plastic cooling plate (200) may include a suitable opening through which the inlet channel (C1) and the outlet channel (C2) can be inserted or pushed into the plastic cooling plate (200). Since the plastic cooling plate (200) is configured to guide coolant from the inlet channel (C1) and the outlet channel (C2), the inlet channel (C1) is positioned within the cavity (201) of the plastic cooling plate (200) in a peripheral area near the first end portion (204) facing the direction opposite to the y direction of the plastic cooling plate (200), whereas the outlet channel (C2) is positioned within the cavity (201) of the plastic cooling plate (200) in a peripheral area near the second end portion (206) on the opposite side facing the y direction of the plastic cooling plate (200) (see, for example, FIG. 5). Of course, when implemented in a battery module, each of the inlet channel (C1) and the outlet channel (C2) has an opening positioned so that coolant can flow from the inlet channel (C1) into the plastic cooling plate (200) and, conversely, coolant can be discharged from the plastic cooling plate (200) to the outlet channel (C2). Consequently, when used during the operation of the battery module, the coolant is conducted from each first end portion (204) to each opposite second end portion (206) along the entire length of the cavity (201) of each plastic cooling plate (200).

[0148] A method for controlling a battery module according to one embodiment of the present disclosure will be described with reference to FIG. 6. Similar to the embodiment of FIG. 2, in the embodiment illustrated in FIG. 6, each battery cell may be cooled on each of its main sides (13, 14). FIG. 6 is illustrated with a battery module (100) having only six battery cells as an example for the sake of simplification of the drawing, where the six battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3) are arranged into two battery cell stacks, namely a first battery cell stack containing three battery cells (1a1, 1a2, 1a3) and a second battery cell stack containing battery cells (1b1, 1b2, 1b3).

[0149] Additionally, the battery module (100) includes a cooling system comprising a plurality of plastic cooling plates (P1, P2, P3, P4) as well as an inlet channel (C1) and an outlet channel (C2). These are fluidly connected to each other in a manner similar to the arrangement of the embodiment of FIG. 2, but the difference is that when viewed along the x direction, the last plastic cooling plate is formed by the fourth plastic cooling plate (P4), and the inner plastic cooling plate includes only the second plastic cooling plate (P2) and the third plastic cooling plate (P3).

[0150] As shown in FIG. 6, the temperature sensor (S 11 , S 12 , S 13 , S 21 , S 22 , S 23 ) is attached to the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3) so that one temperature sensor is provided per battery cell. Temperature sensor (S 11 , S 12 , S 13 , S 21 , S 22 , S 23Each of the following is configured to measure the temperature of each corresponding battery cell (1a1, 1a2, 1a3, 1b1, 1b2, 1b3) and generate a temperature signal corresponding to the measured temperature. Each data line (L 11 , L 12 , L 13 , L 21 , L 22 , L 23 Through ), the temperature sensor (S 11 , S 12 , S 13 , S 21 , S 22 , S 23 ) are each connected to the controller (40). Therefore, the temperature sensor (S 11 , S 12 , S 13 , S 21 , S 22 , S 23 The temperature signal generated by ) is each data line (L 11 , L 12 , L 13 , L 21 , L 22 , L 23 It can be transmitted to a controller (40) via ), and the controller (40) is configured to receive and evaluate the temperature signal. In the illustrated embodiment, the data line (L 11 , L 12 , L 13 , L 21 , L 22 , L 23 ) can be provided by an electrical connection wire (e.g., a wire). In another embodiment, a data line (L 11 , L 12 , L 13 , L 21 , L 22 , L 23) can be implemented as a wireless data connection. Additionally, the controller (40) can be implemented as an electrical circuit including a microprocessor, CPU, etc. The controller (40) can be integrated into a battery management system (BMS) (42) of the battery module (100) as described above.

[0151] The controller (40) is a temperature sensor (S 11 , S 12 , S 13 , S 21 , S 22 , S 23 Based on a temperature signal generated and received by the controller, the controller is configured to evaluate whether thermal runaway is occurring in at least one of the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3). To this end, the controller (40) may be configured to evaluate temperature values ​​based on the received temperature signals and compare each of these temperature values ​​with a respective first threshold. If the temperature value exceeds the first threshold, the controller (40) may estimate (or determine) that thermal runaway is occurring in one of the battery cells. Alternatively or additionally, the controller (40) may calculate the temperature change per unit of time for each received temperature signal, and each calculated temperature change per unit of time may be compared with a respective second threshold. If the temperature change per unit of time exceeds the second threshold, the controller (40) may estimate (or determine) that thermal runaway is occurring in one of the battery cells. In some embodiments, the controller (40) may estimate (or determine) that thermal runaway is occurring in one of the battery cells when, based on a temperature signal for at least one battery, a first threshold is exceeded and a second threshold is also exceeded at the same time.

[0152] If the controller (40) evaluates (or determines) that thermal runaway is occurring in at least one of the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3), the controller (40) may generate a control signal to control the pump (30). The control signal may be transmitted to the pump (30) via a data line (L0) which may be implemented as an electrical connection wire (e.g., a wire) or a wireless data connection. The pump (30) is fluidly connected to an inlet channel (C1) through an inlet (I). The pump (30) is also fluidly connected to a first reservoir (R1) that provides a "fresh" coolant, i.e., a coolant having a temperature suitable for cooling the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3). The first reservoir (R1) may not be included in the battery module (100) and may be provided as an external element. In another embodiment, the first reservoir (R1) may be included in the battery module (100). The pump (30) is configured to move coolant from the first reservoir (R1) to the inlet (I) of the inlet channel (C1) when operated. Additionally, the outlet (O) of the outlet channel (C2) is connected to a second reservoir (R2) configured to receive the used coolant discharged from the cooling system through the outlet channel (C2).

[0153] During normal operation of the battery module (100), that is, when no thermal runaway is detected, the pump (30) can be operated so that the coolant is guided through each plastic cooling plate (P1, P2, P3, P4) at a first flow rate. However, in an embodiment of operating the cooling system, the flow of the coolant may be interrupted from time to time. During the time interval when the flow of the coolant is interrupted, the pump (30) may be deactivated by the controller (40).

[0154] If the pump (30) is in a deactivated state and the controller (40) evaluates (or determines) that thermal runaway is occurring in at least one of the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3), the controller (40) generates a control signal to activate the pump (30) so that the coolant is guided through the plastic cooling plates (P1, P2, P3, P4) at, for example, a first flow rate or a second flow rate greater than the first flow rate.

[0155] When the pump (30) is activated to pump a coolant at a first flow rate through the plastic cooling plates (P1, P2, P3, P4) and the controller (40) evaluates (or determines) that a thermal runaway is occurring in at least one of the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3), the controller (40) generates a control signal to control the pump (30) so that the coolant is guided at a second flow rate greater than the first flow rate through the plastic cooling plates (P1, P2, P3, P4).

[0156] When one or more battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3) are affected by thermal runaway, a massive amount of heat is generated. A plastic cooling plate (P1, P2, P3, P4) according to an embodiment of the present disclosure is composed of a material that can melt due to this heat, so that the area of ​​the plastic cooling plate (P1, P2, P3, P4) that is in thermal contact with the affected battery cell is melted and penetrated. Due to this process, an opening is created in the body of the plastic cooling plate (P1, P2, P3, P4), through which a coolant can escape to the outside of the plastic cooling plate (P1, P2, P3, P4). Accordingly, the coolant can reach the battery cell affected by thermal runaway through these openings, thereby providing an optimal cooling effect for the affected battery cell and helping to suppress or at least suppress the thermal runaway occurring in the defective battery cell.

[0157] On the other hand, if fresh coolant is replenished through the plastic cooling plate immediately after a thermal runaway occurs or is detected by the controller (40) as described above, the melting process and the process of creating an opening in the plastic cooling plate described above may be delayed (or slowed down). Accordingly, in the embodiment, if the controller (40) detects that a thermal runaway has occurred in at least one of the battery cells (1a1, 1a2, 1a3, 1b1, 1b2, 1b3), it may be configured to disable the pump (30) or reduce the pumping capacity for a time interval (e.g., a predetermined time interval). Then, the flow of coolant guided through the plastic cooling plate (P1, P2, P3, P4) may be interrupted during the time interval, or the flow rate of coolant guided through the plastic cooling plate (P1, P2, P3, P4) may be reduced during the time interval (e.g., a predetermined time interval). As a result, the delay in the melting process described above is avoided, the process of creating openings in the plastic cooling plates (P1, P2, P3, P4) is correspondingly accelerated, and the process of the coolant coming into direct contact with the battery cell affected by thermal runaway can also be accelerated. After the time interval expires, the controller (40) controls the pump (30) so that the coolant is guided through the plastic cooling plates (P1, P2, P3, P4) at a first flow rate or a second flow rate greater than the first flow rate, as described above.

[0158] As such, the method of operation of the battery module according to the present disclosure has been described through the embodiment shown in FIG. 6, but it will be understood that this method of operation can be applied in a corresponding manner to any embodiment of the battery module according to the present disclosure. Explanation of the symbols

[0159] 1a1, ..., 1a8 battery cells 1b1, ..., 1b8 battery cells 1c1, ..., 1c8 battery cells 1d1, ..., 1d8 cell 10, 10' battery module 10a, 10b, 10c, 10d battery cell stack 13,14 Main side of the battery cell case 30 pumps 40 controllers 42 Battery Management System 100 battery modules 200 plastic cooling plates C1 Inflow Channel C2 leak channel P1, P2, P3, P4, P5, P6, P7, P8, P9 plastic cooling plates

Claims

Claim 1 A battery module comprising: a battery cell stack including a plurality of battery cells stacked along a first direction; a plastic cooling plate configured to guide a coolant; a pump; and a controller, wherein each of the plurality of battery cells is in thermal contact with the plastic cooling plate, and the plastic cooling plate comprises a plastic material configured to melt when in thermal contact with a battery cell affected by thermal runaway, and the controller is configured to detect a situation in which at least one of the plurality of battery cells is affected by thermal runaway, and after the thermal runaway of at least one of the plurality of battery cells is detected, to control the pump so that the coolant can be guided through the plastic cooling plate in thermal contact with at least one of the plurality of battery cells at a flow rate increased compared to the flow rate before the thermal runaway is detected. Claim 2 A battery module according to claim 1, wherein the controller is configured to control the pump such that, after a thermal runaway of at least one of the plurality of battery cells is detected and before controlling the pump, the flow of the coolant guided through the plastic cooling plate is interrupted for a time interval or the flow rate of the coolant guided through the plastic cooling plate is reduced for a time interval. Claim 3 In claim 1, each of the plurality of battery cells is rectangular, and when the number of battery cell stacks is greater than one, the battery cell stacks are arranged parallel to each other along the first direction, the plastic cooling plate extends in a direction perpendicular to the first direction, and the plastic cooling plate is a battery module that crosses each battery cell stack. Claim 4 In claim 1, each of the battery cells has a main side, and at least one of the main sides is in contact with the plastic cooling plate, forming a battery module. Claim 5 In paragraph 1, Each of the above battery cells is a battery module sandwiched between two of the above plastic cooling plates. Claim 6 In claim 1, the battery cell stack comprises an even number of N battery cells grouped into N / 2 adjacent battery cell pairs, and each of the N / 2 adjacent battery cell pairs is a battery module sandwiched between two plastic cooling plates. Claim 7 In claim 1, the plastic cooling plate comprises a battery module including a hollow body assembled from two half plates comprising a first material including plastic. Claim 8 A battery module according to claim 7, wherein the two half plates each include a peripheral region, and the peripheral regions are sealed together to form the hollow body. Claim 9 In claim 7, at least one of the two half plates comprises a structure for guiding the coolant and transmitting compressive force between the two half plates, in a battery module. Claim 10 In Paragraph 7, The above hollow body includes an inlay overmolded by the first material of the two half plates, and The above inlay is a battery module comprising a second material different from the first material. Claim 11 In item 10, the above-mentioned second material is a battery module having a higher thermal conductivity than the above-mentioned first material. Claim 12 In Paragraph 10, The above second material is a battery module having higher heat resistance than the above first material. Claim 13 A battery system comprising a battery module according to any one of claims 1 to 12. Claim 14 A vehicle including a battery system according to Paragraph 13. Claim 15 A vehicle comprising a battery module according to any one of paragraphs 1 to 12. Claim 16 A method for controlling a battery module according to any one of claims 1 to 12, comprising the step of: by the controller detecting whether at least one of the plurality of battery cells is affected by thermal runaway; and after detecting thermal runaway, controlling the pump so that the coolant is guided through the plastic cooling plate that is in thermal contact with the battery cell affected by thermal runaway at a flow rate increased compared to the flow rate before the thermal runaway was detected. Claim 17 A method for controlling a battery module according to claim 16, further comprising the step of controlling the pump such that, after detecting the thermal runaway and before controlling the pump, the flow of the coolant guided through the plastic cooling plate is interrupted for a time interval or the flow rate of the coolant guided through the plastic cooling plate is reduced for a time interval.

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