Mitigating thermal runaway propagation using multi-branch coolant system
By employing a multi-branch coolant system and electronic controller in a multi-cell rechargeable energy storage system to detect and regulate coolant flow, the problem of thermal runaway propagation is solved, effectively mitigating thermal runaway events and improving system stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-13
- Publication Date
- 2026-04-17
AI Technical Summary
In multi-cell rechargeable energy storage systems, thermal runaway events cause heat to accumulate and spread, affecting the entire battery array. Existing technologies are unable to effectively mitigate the propagation of thermal runaway.
A multi-branch coolant system is adopted, including a main coolant circuit and parallel coolant branches. The electronic controller detects thermal runaway events, identifies the affected modules, and regulates the coolant flow through flow valves to cut off the coolant flow of unrelated branches, thereby specifically cooling the affected modules and preventing the spread of thermal runaway.
It effectively mitigates the propagation of thermal runaway events, protects the overall performance of the battery system, prevents the chain reaction of thermal runaway, and improves the safety and stability of the system.
Smart Images
Figure CN121885836A_ABST
Abstract
Description
[0001] introduce
[0002] This disclosure relates to the use of multi-branch coolant systems to mitigate thermal runaway propagation in multi-cell rechargeable energy storage systems (RESS).
[0003] Typically, a battery system for generating and storing electrical energy comprises one or more battery cells for powering a load. Multiple battery cells can be arranged close together to form a battery module, and multiple battery modules can be organized into a battery pack array. Batteries can be broadly classified into primary batteries and secondary batteries. Primary batteries, also known as disposable batteries, are designed to be used until depleted, after which they simply need to be replaced with new batteries. Secondary batteries, often called rechargeable batteries, employ specific chemistry that allows them to be repeatedly charged and reused, thus offering economic, environmental, and ease-of-use benefits compared to disposable batteries.
[0004] Rechargeable batteries are used to power a wide variety of items, such as toys, consumer electronics, and motor vehicles. The specific chemistry of rechargeable batteries (such as lithium-ion battery cells) and external factors can cause internal reaction rates to generate significant amounts of heat. Prolonged exposure of battery cells to high temperatures can lead to thermal runaway events, where heat accumulation in an individual cell causes heat to diffuse to neighboring cells in the module and affect the entire battery array. Therefore, effective heat removal is necessary to mitigate heat accumulation and the resulting degradation of battery system performance. Typically, devices such as radiators or cold plates with circulating coolant are used to remove heat from the battery system. Summary of the Invention
[0005] A thermal runaway propagation (TRP) mitigation system for a multi-cell rechargeable energy storage system (RESS) includes a cooling subsystem having multiple battery cells arranged in individual battery modules. The cooling subsystem has a main coolant loop circulating coolant and multiple coolant branches arranged in parallel. Each coolant branch receives a portion of coolant from the main coolant loop to regulate the temperature of one battery module. The cooling subsystem also has one or more flow valves for regulating and distributing coolant from the main coolant loop among the coolant branches. The TRP mitigation system also includes an electronic controller operatively communicating with the cooling subsystem and configured to detect the onset of a thermal runaway event in the RSS. The controller is further configured to identify the battery module exhibiting the onset of a thermal runaway event in the RSS and to identify the coolant branch associated with the target battery module. The controller is also configured to cut off coolant flow to coolant branches unrelated to the battery module exhibiting the onset of a thermal runaway event via one or more flow valves to specifically cool the battery module exhibiting the onset of a thermal runaway event and thus mitigate TRP in the RSS.
[0006] The electronic controller can also be configured to set an alarm indicating that an identified battery module is exhibiting signs of thermal runaway.
[0007] Each battery module may include a corresponding temperature sensor that communicates with an electronic controller and is configured to detect the onset of a thermal runaway event in the corresponding battery module.
[0008] After cutting off coolant flow to coolant branches unrelated to the battery module exhibiting the initiation of a thermal runaway event, the electronic controller can be configured to detect a deterioration of conditions indicating the initiation of a thermal runaway event in the identified battery module, such as a temperature increase. Additionally, the electronic controller can be configured to open coolant flow via one or more flow valves to coolant branches associated with the battery module adjacent to the battery module exhibiting the initiation of a thermal runaway event, to further mitigate the TRP in the RESS.
[0009] The electronic controller can be further configured to cut off coolant flow to the coolant branch associated with the battery module exhibiting the onset of the thermal runaway event when the target battery module is identified as having entered full thermal runaway. Cutting off coolant flow to the affected battery module aims to increase coolant flow to the coolant branch associated with the adjacent battery module and prevent TRP.
[0010] After cutting off coolant flow to coolant branches unrelated to the battery module exhibiting the initiation of a thermal runaway event, the electronic controller can also be configured to identify an additional battery module in the RSS exhibiting the initiation of a thermal runaway event. The electronic controller can further be configured to open coolant flow to each coolant branch associated with the corresponding battery module in the RSS via one or more flow valves.
[0011] The flow valve can be a multi-way valve assembly located at the junction between the main coolant circuit and multiple coolant branches. Such a multi-way valve can be configured to control the coolant flow to each coolant branch.
[0012] Alternatively, multiple throttle valves can regulate the flow rate of coolant from the main coolant circuit. Each throttle valve can be located in one of the coolant branches upstream of the corresponding battery module and configured to control the coolant flow rate to the target coolant branch.
[0013] Each coolant branch may include a one-way valve configured to control the flow of coolant leaving the target coolant branch.
[0014] The cooling subsystem may also include a fluid pump configured to circulate coolant through the main coolant circuit.
[0015] The invention also discloses a motor vehicle employing the thermal runaway propagation (TRP) mitigation system described above, and a method for mitigating thermal runaway propagation (TRP) in a multi-cell rechargeable energy storage system (RESS).
[0016] This disclosure provides the following examples:
[0017] Example 1. A thermal runaway propagation (TRP) mitigation system for a multi-cell rechargeable energy storage system (RESS), the multi-cell rechargeable energy storage system having multiple battery cells arranged in individual battery modules, the system comprising:
[0018] Cooling subsystem, including:
[0019] The main coolant circuit is configured to circulate coolant.
[0020] Multiple coolant branches arranged in parallel, wherein each coolant branch is configured to receive a portion of coolant from the main coolant circuit to adjust the temperature of one of the corresponding battery modules; and
[0021] At least one flow valve is configured to regulate and distribute coolant circulating through the main coolant circuit among the plurality of coolant branches; and
[0022] An electronic controller, operatively communicating with the cooling subsystem, is configured to:
[0023] Detection of thermal runaway events in RESS begins;
[0024] Identify battery modules in RESS that exhibit the initiation of thermal runaway events;
[0025] Identify the coolant branch from the plurality of coolant branches that is associated with the battery module exhibiting the initiation of a thermal runaway event; and
[0026] Coolant flow to a coolant branch unrelated to the battery module exhibiting the onset of a thermal runaway event is cut off via the at least one flow valve to specifically cool the battery module exhibiting the onset of a thermal runaway event, thereby mitigating the TRP in the RESS.
[0027] Example 2. The TRP mitigation system according to Example 1, wherein the electronic controller is further configured to set an alarm indicating that the identified battery module exhibits the initiation of a thermal runaway event.
[0028] Example 3. The TRP mitigation system according to Example 1, wherein each battery module includes a corresponding temperature sensor that communicates with the electronic controller and is configured to detect the onset of a thermal runaway event in the corresponding battery module.
[0029] Example 4. The TRP mitigation system according to Example 1, wherein, after cutting off coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of the thermal runaway event, the electronic controller is further configured to:
[0030] The detection indicates a deterioration in the conditions that would trigger a thermal runaway event in the identified battery module; and
[0031] Coolant flow to the coolant branch associated with the battery module adjacent to the battery module exhibiting the onset of thermal runaway event is opened via the at least one flow valve to further mitigate TRP in the RESS.
[0032] Example 5. The TRP mitigation system according to Example 4, wherein when a target battery module is identified as having entered complete thermal runaway, the electronic controller is further configured to cut off coolant flow to the coolant branch associated with the battery module exhibiting the onset of the thermal runaway event, thereby increasing coolant flow to the coolant branch associated with the adjacent battery module.
[0033] Example 6. The TRP mitigation system according to Example 1, wherein, after cutting off coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of the thermal runaway event, the electronic controller is further configured to:
[0034] Identify the additional battery module in the RESS that exhibits the initiation of a thermal runaway event; and
[0035] Coolant flow is opened via the at least one flow valve to each coolant branch associated with the corresponding battery module in the RESS.
[0036] Example 7. The TRP mitigation system according to Example 1, wherein the at least one flow valve is a multi-way valve assembly arranged at the junction between the main coolant circuit and the plurality of coolant branches, and configured to control the coolant flow to each coolant branch.
[0037] Example 8. The TRP mitigation system according to Example 1, wherein the at least one flow valve is a plurality of throttle valves, each throttle valve being arranged in one of the plurality of coolant branches upstream of the corresponding battery module and configured to control the coolant flow to the target coolant branch.
[0038] Example 9. The TRP mitigation system according to Example 1, wherein each coolant branch includes a one-way valve configured to control the coolant flow rate leaving the target coolant branch.
[0039] Example 10. A method for mitigating thermal runaway propagation (TRP) in a multi-cell rechargeable energy storage system (RESS) having multiple battery cells arranged in individual battery modules, the method comprising:
[0040] The monitoring of a thermal runaway event in the RESS begins via an electronic controller, wherein the electronic controller is operatively in communication with a cooling subsystem, the cooling subsystem comprising:
[0041] The main coolant circuit is configured to circulate coolant.
[0042] Multiple coolant branches arranged in parallel, wherein each coolant branch is configured to receive a portion of coolant from the main coolant circuit to adjust the temperature of one of the corresponding battery modules; and
[0043] At least one flow valve is configured to regulate and distribute coolant circulating through the main coolant circuit among the plurality of coolant branches;
[0044] The thermal runaway event in the RSS is detected by the electronic controller.
[0045] The electronic controller identifies battery modules in the RESS that exhibit the initiation of a thermal runaway event;
[0046] The electronic controller identifies, from the plurality of coolant branches, the coolant branch associated with the battery module exhibiting the initiation of a thermal runaway event; and
[0047] The electronic controller uses at least one flow valve to cut off the coolant flow to a coolant branch unrelated to the battery module exhibiting the onset of a thermal runaway event, thereby specifically cooling the battery module exhibiting the onset of a thermal runaway event and thus mitigating the TRP in the RESS.
[0048] Example 11. The method according to Example 10 further includes: setting an alarm via the electronic controller, the alarm indicating that the identified battery module exhibits the initiation of a thermal runaway event.
[0049] Example 12. The method according to Example 10, wherein each battery module includes a corresponding temperature sensor that communicates with the electronic controller, and the method further includes using the associated temperature sensor to detect the onset of a thermal runaway event in the corresponding battery module.
[0050] Example 13. The method of Example 10, after cutting off coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of a thermal runaway event, the method further includes:
[0051] The electronic controller detects the deterioration of conditions that indicate the onset of a thermal runaway event in the battery module; and
[0052] The electronic controller uses at least one flow valve to open the coolant flow to the coolant branch associated with the battery module adjacent to the battery module exhibiting the onset of thermal runaway event, in order to further mitigate the TRP in the RESS.
[0053] Example 14. The method according to Example 13 further includes: when the target battery module is identified as having entered complete thermal runaway, cutting off coolant flow to the coolant branch associated with the battery module exhibiting the onset of the thermal runaway event via the electronic controller, thereby increasing coolant flow to the coolant branch associated with the adjacent battery module.
[0054] Example 15. The method according to Example 11, after cutting off coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of a thermal runaway event, the method further includes:
[0055] The electronic controller identifies the additional battery module in the RESS that exhibits the initiation of a thermal runaway event; and
[0056] The electronic controller uses at least one flow valve to open the coolant flow to each coolant branch associated with the corresponding battery module in the RESS.
[0057] Example 16. A motor vehicle comprising:
[0058] The electric motor-generator is configured to produce torque.
[0059] A multi-cell rechargeable energy storage system (RESS) is configured to supply electrical energy to the electric motor-generator, the RESS comprising:
[0060] Multiple battery cells arranged in an individual battery module; and
[0061] Cooling subsystem, including:
[0062] The main coolant circuit is configured to circulate coolant.
[0063] Multiple coolant branches arranged in parallel, each coolant branch configured to receive a portion of coolant from the main coolant circuit to adjust the temperature of one of the corresponding battery modules, and each coolant branch including a one-way valve configured to control the coolant flow rate leaving a target coolant branch; and
[0064] At least one flow valve is configured to regulate and distribute coolant circulating through the main coolant circuit among the plurality of coolant branches; and
[0065] An electronic controller, operatively communicating with the cooling subsystem, is configured to:
[0066] Detection of thermal runaway events in RESS begins;
[0067] Identify battery modules in RESS that exhibit the initiation of thermal runaway events;
[0068] Identify the coolant branch from the plurality of coolant branches that is associated with the battery module exhibiting the initiation of a thermal runaway event; and
[0069] Coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of a thermal runaway event is cut off via the at least one flow valve to specifically cool the battery module exhibiting the initiation of a thermal runaway event, thereby mitigating thermal runaway propagation (TRP) in the RESS.
[0070] Example 17. The motor vehicle according to Example 16, wherein each battery module includes a corresponding temperature sensor, the corresponding temperature sensor communicating with the electronic controller and configured to detect the onset of a thermal runaway event in the corresponding battery module.
[0071] Example 18. The motor vehicle according to Example 16, wherein, after cutting off coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of a thermal runaway event, the electronic controller is further configured to:
[0072] The detection indicates a deterioration in the conditions that would trigger a thermal runaway event in the identified battery module; and
[0073] Coolant flow is opened via the at least one flow valve to the coolant branch associated with the battery module around the battery module exhibiting the onset of thermal runaway events, in order to further mitigate TRP in the RESS.
[0074] Example 19. The motor vehicle according to Example 18, wherein the electronic controller is further configured to cut off coolant flow to a coolant branch associated with a battery module exhibiting the onset of a thermal runaway event.
[0075] Example 20. In the motor vehicle according to Example 16, after cutting off coolant flow to a coolant branch unrelated to the battery module exhibiting the initiation of a thermal runaway event, the electronic controller is further configured to:
[0076] Identify the additional battery module in the RESS that exhibits the initiation of a thermal runaway event; and
[0077] Coolant flow is opened via the at least one flow valve to each coolant branch associated with the corresponding battery module in the RESS.
[0078] The foregoing features and advantages, as well as other features and advantages, of this disclosure will become apparent from the following detailed description of one or more embodiments and one or more best modes for carrying out the disclosure when understood in conjunction with the accompanying drawings and claims. Attached Figure Description
[0079] Figure 1 This is a schematic top view of an embodiment of a motor vehicle according to the present disclosure, which employs multiple power sources, a multi-cell rechargeable energy storage system (RESS) configured to generate and store electrical energy used by the vehicle system, and a thermal runaway propagation (TRP) mitigation system.
[0080] Figure 2 It is based on the purpose of this disclosure. Figure 1 The schematic diagram of the TRP mitigation system of the RESS shown includes an embodiment of a cooling subsystem having a main coolant circuit and multiple parallel coolant branches for removing heat energy from individual battery modules.
[0081] Figure 3 It is based on the purpose of this disclosure. Figure 1 The schematic diagram of the TRP mitigation system of the RESS shown is another embodiment of the TRP mitigation system, which includes a cooling subsystem with a main coolant circuit and multiple parallel coolant branch subsystems for removing heat energy from individual battery modules.
[0082] Figure 4 The diagram illustrates the use of Figure 1-3 The method for mitigating thermal runaway propagation (TRP) in the multi-cell RESS of the coolant subsystem shown. Detailed Implementation
[0083] The embodiments described herein are intended to be illustrative. Other embodiments may take various alternative forms. Furthermore, the drawings are generally schematic and not necessarily drawn to scale. Some features may be exaggerated or minimized to show detail of particular components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but are merely representative bases for teaching those skilled in the art to employ this disclosure in various ways.
[0084] Some terms used in the following description may be for illustrative purposes only and are therefore not intended to be limiting. Terms such as “above” and “below” refer to orientations in the referenced figures. Terms such as “front,” “rear,” “front,” “rear,” “left,” “right,” “rear,” “side,” “up,” “down,” “top,” and “bottom” describe the orientation and / or position of parts of a component or element within a consistent but arbitrary frame of reference, which becomes clear from the text describing the component or element under discussion and the associated figures.
[0085] Furthermore, terms such as "first," "second," and "third" may be used to describe individual components. Such terms may include the words specifically mentioned above, their derivatives, and words with similar meanings, and are used to describe the accompanying drawings, and do not represent a limitation on the scope of this disclosure as defined by the appended claims. Additionally, the teachings herein may be described in the form of functional and / or logical block components and / or various processing steps. It should be understood that such block components may include multiple hardware, software, and / or firmware components configured to perform a specified function.
[0086] Referring to the accompanying drawings, similar reference numerals refer to similar parts. Figure 1 A schematic diagram of a motor vehicle 10 having a powertrain 12 is shown. The vehicle 10 may include, but is not limited to, commercial vehicles, industrial vehicles, passenger vehicles, aircraft, watercraft, trains, etc. It is also envisioned that the vehicle 10 may be a mobile platform, such as an aircraft, an all-terrain vehicle (ATV), a boat, a personal mobility device, a robot, etc., to achieve the purposes of this disclosure. The powertrain 12 includes a power source 14, which is configured to generate a power source torque T (e.g., ...). Figure 1 (As shown) is used to propel the vehicle 10 relative to the road surface 18 via the drive wheel 16. The power source 14 is depicted as an electric motor-generator.
[0087] like Figure 1 As shown, powertrain 12 may include an additional power source 20, such as an internal combustion engine. Power sources 14 and 20 can work together to power vehicle 10. Vehicle 10 also includes a central processing unit (CPU) 22 and a multi-battery unit rechargeable energy storage system (RESS) 24, which is configured to generate and store electrical energy through a thermoelectric electrochemical reaction to supply electrical energy to power sources 14 and 20. CPU 22 regulates various systems of vehicle 10, including powertrain 12, to generate a predetermined amount of power source torque T. RESS 24 can be connected to power sources 14 and 20, electronic CPU 22, and other vehicle systems via a high-voltage data bus or BUS 25.
[0088] like Figure 1-3As shown, RESS 24 includes multiple battery cells 28, such as lithium-ion rechargeable battery cells, arranged in individual battery packs or modules, such as first module 30-1, second module 30-2, and third module 30-3. Target modules 30-1, 30-2, and 30-3 can be arranged electrically in series or in parallel. Although three individual battery modules are specifically shown, RESS 24 is intended to include at least two corresponding modules, and multiple modules can be organized into battery packs or sub-packs. The remainder of this description will focus on the construction of RESS 24 with three battery modules 30-1, 30-2, and 30-3, where each battery module has a desired number of battery cells 28. Figure 2 and 3 As shown, each battery module 30-1, 30-2, 30-3 includes a corresponding battery module housing 32-1, 32-2, 32-3, which is connected to the chassis ground and configured to house and support the corresponding battery cell 28. The RESS24 may also include a battery pack housing 33, which is surrounded by an environment 34 and configured to house and support the battery modules 30-1, 30-2, 30-3 (e.g., ...). Figure 1 (as shown in the image).
[0089] like Figure 2 and 3 As shown, RESS 24 also includes a cooling subsystem 36 configured to remove heat from various temperature-sensitive components of the RESS. Cooling subsystem 36 includes a main coolant circuit 38 configured to circulate coolant 40 through RESS 24. As also shown, cooling subsystem 36 includes a fluid pump 42 configured to circulate coolant 40 through the main coolant circuit 38. Cooling subsystem 36 also includes multiple coolant branches, shown as a first branch 44-1, a second branch 44-2, and a third branch 44-3, in fluid communication with the main coolant circuit 38. Each coolant branch 44-1, 44-2, 44-3 extends through corresponding battery modules 30-1, 30-2, 30-3, close to and along the constituent battery cell 28.
[0090] Furthermore, each coolant branch 44-1, 44-2, 44-3 is configured to receive a portion of coolant 40 from the main coolant circuit 38. The coolant branches 44-1, 44-2, 44-3 are arranged in parallel flow to receive their respective portions of coolant 40. The coolant branches 44-1, 44-2, 44-3 are thus configured to independently circulate their respective portions of coolant 40 and adjust the temperature of their corresponding battery modules 30-1, 30-2, 30-3 (by removing or adding heat). Therefore, each coolant branch 44-1, 44-2, 44-3 passes through one of the battery module housings 32-1, 32-2, 32-3. As shown in the figure, the main coolant circuit 38 can be in fluid communication with additional parallel coolant branches, such as those used to circulate coolant through the auxiliary power module (APM), the battery disconnect unit (BDU) including various electrical switches and relays, electrical connectors, and DC / DC converters for supplying 12V / 48V power to the vehicle, each of which has specific temperature requirements.
[0091] Continue to refer to Figure 2 and 3 RESS 24 may also include an inlet manifold 46 and an outlet manifold 48, the inlet manifold 46 being configured to connect the main coolant circuit 38 to coolant branches 44-1, 44-2, 44-3, and the outlet manifold 48 being configured to connect the coolant branches back to the main coolant circuit. Thus, the inlet and outlet manifolds 46 and 48 are together configured to maintain the circulation of coolant 40 through the cooling subsystem 36. The cooling subsystem 36 also includes at least one flow valve 50. One or more flow valves 50 are configured to regulate and distribute the coolant 40 circulating through and received from the main coolant circuit 38 among the individual coolant branches 44-1, 44-2, 44-3. In other words, one or more flow valves 50 are specifically constructed and operated to provide independent regulation of the coolant flow to each individual coolant branch 44-1, 44-2, 44-3.
[0092] like Figure 2 As shown, the flow valve 50 may be a multi-way valve assembly arranged in a connector (e.g., inlet manifold 46) between the main coolant circuit 38 and multiple coolant branches 44-1, 44-2, 44-3 upstream of each battery module 30-1, 30-2, 30-3. An embodiment of the multi-way valve assembly of the flow valve 50 may be configured to control the flow rate of coolant 40 to each coolant branch 44-1, 44-2, 44-3. Figure 3As shown, one or more flow valves 50 may be multiple individual throttle valves 50-1, 50-2, 50-3. Each target throttle valve 50-1, 50-2, 50-3 may be arranged in one of multiple coolant branches 44-1, 44-2, 44-3 upstream of the corresponding battery module 30-1, 30-2, 30-3 and configured to control the flow rate of coolant 40 to the target coolant branch.
[0093] like Figure 2 and Figure 3 As shown, each coolant branch 44-1, 44-2, 44-3 may include a corresponding check valve 52-1, 52-2, 52-3. Check valves 52-1, 52-2, 52-3 are configured to prevent coolant 40 from flowing back into the corresponding coolant branch 44-1, 44-2, 44-3. Each of the check valves 52-1, 52-2, 52-3 is arranged downstream of flow valve(s) 50 and downstream of the corresponding battery modules 30-1, 30-2, 30-3. Therefore, each check valve 52-1, 52-2, 52-3 is configured to control the flow rate of the corresponding portion of coolant 40 through and out of the target coolant branch 44-1, 44-2, 44-3. The cooling subsystem 36 may also include multiple heat exchangers arranged in the main coolant circuit 38 for changing the temperature of the coolant 40. For example, one embodiment of such a heat exchanger could be a coolant chiller 54-1, which, for example, uses a refrigerant to remove heat from the coolant 40 in the main coolant circuit 38. Another embodiment of such a heat exchanger could be a coolant heater 54-2, which, for example, uses a resistor to add heat to the coolant 40.
[0094] like Figure 1-3 As shown, the multi-cell RESS 24 may also include an electronic controller 56, which may be electronically connected to or become part of the CPU 22. The electronic controller 56 is operatively in communication with the cooling subsystem 36, i.e., configured or programmed to regulate the operation of the cooling subsystem, and may be configured to manage the operation of the entire RESS 24. As shown, the electronic controller 56 is operatively in communication with the fluid pump 42, one or more flow valves 50, the coolant cooler 54-1, and the coolant heater 54-2. To support the necessary management of the RESS 24 and / or the cooling subsystem 36, the electronic controller 56 specifically includes a processor and a tangible, non-transient memory containing the necessary instructions programmed therein. The controller's memory may be a suitable recordable medium involved in providing computer-readable data or process instructions. Such a recordable medium may take various forms, including but not limited to non-volatile and volatile media.
[0095] The non-volatile media of the electronic controller 56 may include, for example, optical discs or magnetic disks and other persistent storage. Volatile media may include, for example, dynamic random access memory (DRAM), which may constitute the main memory. Instructions programmed into the controller 56 may be transmitted via one or more transmission media or via a wireless connection, including coaxial cables, copper wires, and optical fibers, including wires forming a system bus coupled to the computer processor. The memory of the electronic controller 56 may also include floppy disks, hard disks, magnetic tapes, other magnetic media, CD-ROMs, DVDs, other optical media, etc. The electronic controller 56 may be configured or equipped with other necessary computer hardware, such as a high-speed clock, necessary analog-to-digital (A / D) and / or digital-to-analog (D / A) circuitry, input / output circuitry and devices (I / O), and appropriate signal conditioning and / or buffering circuitry.
[0096] Electronic controller 56 can be configured to regulate the flow rate of coolant 40 to individual battery modules 30-1, 30-2, 30-3 via fluid pump 42 and flow valve(s) 50. Algorithms(s) required or accessible to electronic controller 56 (typically indicated by digit 58) can be stored in the controller's memory and executed automatically to facilitate the operation of RESS 24 and / or cooling subsystem 36. The function of cooling subsystem 36 can be regulated by electronic controller 56 under normal operating conditions and for the purpose of mitigating extreme or abnormal conditions contemplated herein and described in detail below.
[0097] Normally, during normal RSS operation, the coolant flow through coolant branches 44-1, 44-2, and 44-3 effectively absorbs the heat released by the battery cells 28 in the individual battery modules 30-1, 30-2, and 30-3. However, during extreme conditions, such as during thermal runaway events ( Figure 2 and 3 (Identified by the number 60), the amount of heat released by a battery cell experiencing this event may saturate the corresponding coolant branch and exceed the ability of the relevant battery module to efficiently transfer heat (e.g., from the battery pack casing 33 to the surrounding environment 34). Therefore, excessive heat will typically be transferred between adjacent battery cells of the corresponding battery module and between adjacent modules, leading to thermal runaway propagation via RESS 24. Thus, the term "thermal runaway event" generally refers to an uncontrolled rise in temperature within the battery system.
[0098] During such a thermal runaway event 60, the heat generated within the battery system or battery cell exceeds the heat dissipated, causing the temperature to rise further. Thermal runaway events can be triggered by various conditions within the RESS, including internal short circuits within the battery cell, improper use of the battery cell, physical abuse, manufacturing defects, or exposure of the battery cell to extreme external temperatures. For example, if a battery cell 28 in the first battery module 30-1 experiences a thermal runaway event 60, the excess gas generated by this event will cause a significant increase in internal battery cell pressure, potentially leading to the rupture of the target battery cell's casing.
[0099] If the casing of battery cell 28 ruptures, the high-temperature gas emitted by the target battery cell (temperatures up to 1500 degrees Celsius) could cause battery cell debris to pass through the first battery module 30-1, thereby triggering thermal runaway in adjacent battery cells 28 and causing thermal runaway propagation (TRP) through the first battery module. Furthermore, thermal runaway event 60 could propagate from the first battery module 30-1 to the second battery module 30-2 and trigger thermal runaway in its battery cells 28. Therefore, the transmission of such high-temperature gas and / or debris generally increases the likelihood of a chain reaction TRP occurring in RESS 24.
[0100] like Figure 1 As shown, vehicle 10 also includes a TRP mitigation system 62 for RESS 24, and electronic controller 56 is programmed with one or more specific algorithms 58 for operating the target TRP mitigation system. Specifically, the algorithms 58 include a stock mode configured to monitor the onset of a thermal runaway event in RESS 24 as flow of coolant 40 is delivered to each coolant branch 44-1, 44-2, 44-3. Electronic controller 56 is also configured to detect the onset of a thermal runaway event 60 in RESS 24. This detection of the onset of the thermal runaway event 60 can be achieved using temperature sensors 62-1, 62-2, 62-3 arranged at the battery module level (within the corresponding battery module housings 32-1, 32-2, 32-3) and / or sensors 64 at the battery pack level (inside housing 33).
[0101] The electronic controller 56 is also configured to identify specific battery modules 30-1, 30-2, or 30-3 exhibiting the initiation of a thermal runaway event 60, i.e., identifying modules affected by heat. For example, modules affected by heat can be identified via signals transmitted to the electronic controller 56 from specific temperature sensors 62-1, 62-2, 62-3 or via gas sensors (not shown) disposed within the corresponding battery module housings 32-1, 32-2, 32-3. The initiation of the thermal runaway event 60 can also be identified via the electronic controller 56 using other early indicators, such as detecting battery cells or modules exhibiting a high self-discharge rate that results in a voltage drop compared to adjacent battery cells. The electronic controller 56 is also configured to identify from the coolant branches 44-1, 44-2, 44-3 the coolant branches associated with the battery module 30-1, 30-2, or 30-3 exhibiting the initiation of the detected thermal runaway event 60. The electronic controller 56 is also configured to cut off the flow of coolant 40 to a coolant branch unrelated to the battery module exhibiting the initiation of thermal runaway event 60 via one or more flow valves 50. This action is intended to specifically and exclusively cool the heat-affected module (excluding other battery modules in the RESS) and thus mitigate the TRP in RESS 24.
[0102] For example, battery module 30-1 can be identified as exhibiting the onset of thermal runaway event 60. In this case, coolant branches 44-2 and 44-3 will be identified as associated with battery modules 30-2 and 30-3, i.e., unrelated to the affected battery module 30-1. The controller 56 will then use multi-way valve 50 or throttle valves 50-2 and 50-3 to cut off the flow of coolant 40 to coolant branches 44-2 and 44-3. The electronic controller 56 can also be configured to set (i.e., command or trigger) an alarm 66 indicating that the identified battery module has exhibited the onset of thermal runaway event 60. In other words, alarm 66 can notify the system user or technician directly of thermal damage to a specific battery module and the risk of triggering a TRP via sensor signals or fault codes (e.g., via an infotainment display, vehicle data port, vehicle lighting system, etc.) or via a remote server (not shown).
[0103] After cutting off coolant flow to coolant branches unrelated to the heat-affected battery module (such as branches 44-2 and 44-3), the electronic controller 56 can detect a deterioration of the conditions indicating the onset of a thermal runaway event 60 in the identified battery module 30-1. For example, the internal temperature of the target battery module may be one of the conditions indicating the onset of a thermal runaway event 60 in battery module 30-1. In this case, a sustained increase in temperature in battery module 30-1 detected via sensor 62-1 (e.g., an increase programmed to a predefined value 68 in the electronic controller 56) can be considered as satisfying the target deterioration condition.
[0104] Upon detecting such deterioration, the electronic controller 56 can command the flow of coolant 40 to the coolant branch associated with one or more battery modules (e.g., module 30-2) adjacent to or surrounding the heat-affected battery module (30-1) via flow valve 50 to further mitigate TRP in RESS 24. When it is identified that the heat-affected battery module has entered complete thermal runaway, the electronic controller 56 can be additionally configured to cut off the flow of coolant 40 to the coolant branch associated with said heat-affected battery module (e.g., branch 44-1). This cutoff of coolant flow to the affected battery module aims to increase the flow of coolant to the coolant branches associated with one or more adjacent or surrounding battery modules (e.g., module 30-2) to prevent TRP. Furthermore, cutting off coolant flow to the affected battery module (e.g., 30-1) can prevent coolant line rupture within the coolant branches of adjacent modules (e.g., 44-2 or 44-3) if the temperature exceeds the coolant path temperature capability.
[0105] Furthermore, after cutting off coolant flow to coolant branches unrelated to the identified heat-affected battery modules (such as branches 44-2 and 44-3), the electronic controller 56 can identify additional battery modules (such as module 30-2 or 30-3) exhibiting the initiation of a thermal runaway event 60. If such an identification is made, the electronic controller 56 can open the flow of coolant 40 to each coolant branch 44-1, 44-2, and 44-3 associated with the corresponding battery modules 30-1, 30-2, and 30-3 in RESS 24 via one or more flow valves 50. Opening each coolant branch will distribute the available coolant flow substantially uniformly among the battery modules in an attempt to control thermal stress in RESS 24 overall.
[0106] Methods for detecting and mitigating thermal runaway propagation (TRP) in multi-cell rechargeable energy storage systems (such as RESS24) 100 Figure 4 As shown and referenced below Figure 1-3 The structure shown is described below. This method is specifically designed for use in a RESS employing a main coolant circuit (e.g., main coolant circuit 38) and multiple coolant branches (e.g., branches 44-1, 44-2, 44-3), the main coolant circuit being connected to a fluid pump, the multiple coolant branches being arranged in parallel, each coolant branch being configured to receive a portion of coolant 40 from the main coolant circuit. The target RESS also employs at least one flow valve 50 configured to regulate and distribute the coolant 40 received from the main coolant circuit 38 among the multiple coolant branches 44-1, 44-2, 44-3.
[0107] Method 100 begins in block 102 by monitoring the onset of a thermal runaway event 60 in RESS 24 via an electronic controller 56 (e.g., using corresponding temperature sensors 62-1, 62-2, 62-3 and / or 64) as coolant 40 flow is delivered to each coolant branch 44-1, 44-2, 44-3. Following block 102, the method proceeds to block 104. In block 104, the method includes detecting the onset of the thermal runaway event 60 in RESS 24 via the electronic controller 56. Following block 104, the method proceeds to block 106. In block 106, the method includes identifying a battery module (e.g., module 30-1) exhibiting the onset of the thermal runaway event 60 via the electronic controller 56.
[0108] After completing block 106, the method proceeds to block 108. In block 108, the method includes identifying, via electronic controller 56, a coolant branch associated with the battery module exhibiting the initiation of thermal runaway event 60, such as cooling branch 44-1 which delivers coolant to battery module 30-1. After block 108, the method proceeds to block 110. In block 110, the method includes cutting off the flow of coolant 40 to coolant branches (e.g., branches 44-2 and 44-3) unrelated to the thermally affected battery module via flow valve(s) 50 regulated by electronic controller 56. As described above regarding... Figure 1-3 The aforementioned cut-off of coolant 40 in the coolant branch leading to the unaffected battery modules is intended specifically to cool the heat-affected battery modules, such as module 30-1, and thereby alleviates the TRP in RESS24.
[0109] Following block 110, the method may proceed to block 112. In block 112, the method includes setting an alarm 66 via electronic controller 56, which signals that a thermally affected battery module has been identified. Alarm 66 may identify the fact that flow to a branch of coolant 40 to other battery modules in RESS 24 has been cut off for a particular battery module. Alternatively, after cutting off the flow of coolant 40 to coolant branches unrelated to the thermally affected battery module in block 110 and / or setting alarm 66 in block 112, method 100 may proceed to block 114. In block 114, the method may include detecting, via electronic controller 56, a deterioration of conditions indicating that a thermal runaway event 60 has begun (e.g., a temperature rise) in the identified battery module (e.g., module 30-1).
[0110] Following block 114, the method may proceed to block 116 and include opening the flow of coolant 40 to a coolant branch associated with a battery module adjacent to the thermally affected battery module via an electronic controller 56 using one or more flow valves 50, to further alleviate the TRP in RESS 24. Following block 116, the method may continue to block 118. In block 118, the method includes identifying, for example, a thermally affected battery module (e.g., module 30-1) that has entered complete thermal runaway via a corresponding temperature sensor (e.g., sensor 62-1). Following such identification, the method includes cutting off the flow of coolant 40 to the thermally affected coolant branch via an electronic controller 56, thereby increasing the flow of coolant to the coolant branch associated with the adjacent battery module (e.g., branch 44-2).
[0111] Method 100 can also proceed from box 110 or box 112 to box 120. In box 120, the method includes identifying, via electronic controller 56, an additional battery module (e.g., 30-2 or 30-3) exhibiting the initiation of a thermal runaway event 60. After box 120, the method can proceed to box 122 and include opening the flow of coolant 40 to each coolant branch (e.g., 44-2 or 44-3) associated with the corresponding battery module in RESS 24 via electronic controller 56 using one or more flow valves 50. After any of boxes 110, 112, 116, 118, or 122, the method can cycle back to box 102 to continue monitoring RESS 24. Alternatively, if RESS 24 has entered TRP, the method can cut off the current flow in the RESS and terminate in box 124. In another alternative, if the electrical load on RESS24 has been removed, for example, vehicle 10 has stopped, power sources 14 and 20 have been turned off, and fluid pump 42 has been deactivated, the method may end in box 126.
[0112] The detailed description and accompanying drawings support and describe this disclosure, but the scope of this disclosure is defined only by the claims. While some best modes and other embodiments for implementing the claimed disclosure have been described in detail, various alternative designs and embodiments exist to practice the disclosure as defined in the appended claims. Furthermore, the features of the embodiments illustrated in the drawings or the various embodiments mentioned in this description are not necessarily to be construed as embodiments independent of each other. Rather, each feature described in one of the examples of embodiments may be combined with one or more other desired features from other embodiments to produce other embodiments not described in the text or with reference to the drawings. Therefore, these other embodiments fall within the framework and scope of the appended claims.
Claims
1. A thermal runaway propagation (TRP) mitigation system for a multi-cell rechargeable energy storage system (RESS), the multi-cell rechargeable energy storage system having multiple battery cells arranged in individual battery modules, the system comprising: Cooling subsystem, including: The main coolant circuit is configured to circulate coolant. Multiple coolant branches arranged in parallel, wherein each coolant branch is configured to receive a portion of coolant from the main coolant circuit to adjust the temperature of one of the corresponding battery modules; and At least one flow valve is configured to regulate and distribute coolant circulating through the main coolant circuit among the plurality of coolant branches; and An electronic controller, operatively communicating with the cooling subsystem, is configured to: Detection of thermal runaway events in RESS begins; Identify battery modules in RESS that exhibit the initiation of thermal runaway events; Identify the coolant branch from the plurality of coolant branches that is associated with the battery module exhibiting the initiation of a thermal runaway event; and Coolant flow to a coolant branch unrelated to the battery module exhibiting the onset of a thermal runaway event is cut off via the at least one flow valve to specifically cool the battery module exhibiting the onset of a thermal runaway event, thereby mitigating the TRP in the RESS.
2. The TRP mitigation system of claim 1, wherein the electronic controller is further configured to set an alarm indicating that the identified battery module exhibits signs of the onset of a thermal runaway event.
3. The TRP mitigation system of claim 1, wherein each battery module includes a corresponding temperature sensor, the corresponding temperature sensor communicating with the electronic controller and configured to detect the onset of a thermal runaway event in the corresponding battery module.
4. The TRP mitigation system of claim 1, wherein, After cutting off coolant flow to coolant branches unrelated to the battery module where the thermal runaway event began, the electronic controller is further configured to: The detection indicates a deterioration in the conditions that would trigger a thermal runaway event in the identified battery module; as well as Coolant flow to the coolant branch associated with the battery module adjacent to the battery module exhibiting the onset of thermal runaway event is opened via the at least one flow valve to further mitigate TRP in the RESS.
5. The TRP mitigation system of claim 4, wherein, When a target battery module is identified as having entered complete thermal runaway, the electronic controller is also configured to cut off coolant flow to the coolant branch associated with the battery module exhibiting the onset of the thermal runaway event, thereby increasing coolant flow to the coolant branch associated with the adjacent battery module.
6. The TRP mitigation system of claim 1, wherein, After cutting off coolant flow to coolant branches unrelated to the battery module where the thermal runaway event began, the electronic controller is further configured to: Identify the additional battery module in the RESS that exhibits the initiation of a thermal runaway event; as well as Coolant flow is opened via the at least one flow valve to each coolant branch associated with the corresponding battery module in the RESS.
7. The TRP mitigation system of claim 1, wherein the at least one flow valve is a multi-way valve assembly disposed at a junction between the main coolant circuit and the plurality of coolant branches, and configured to control the coolant flow to each coolant branch.
8. The TRP mitigation system of claim 1, wherein the at least one flow valve is a plurality of throttle valves, each throttle valve being arranged in one of the plurality of coolant branches upstream of the corresponding battery module and configured to control the coolant flow rate to the target coolant branch.
9. The TRP mitigation system of claim 1, wherein each coolant branch includes a one-way valve configured to control the coolant flow rate leaving the target coolant branch.
10. A method for mitigating thermal runaway propagation (TRP) in a multi-cell rechargeable energy storage system (RESS), the multi-cell rechargeable energy storage system having multiple battery cells arranged in individual battery modules, the method comprising: The thermal runaway event in the RESS is initiated by an electronic controller that is operatively in communication with a cooling subsystem, the cooling subsystem comprising: The main coolant circuit is configured to circulate coolant. Multiple coolant branches arranged in parallel, wherein each coolant branch is configured to receive a portion of coolant from the main coolant circuit to adjust the temperature of one of the corresponding battery modules; and At least one flow valve is configured to regulate and distribute coolant circulating through the main coolant circuit among the plurality of coolant branches; The thermal runaway event in the RSS is detected by the electronic controller. The electronic controller identifies battery modules in the RESS that exhibit the initiation of a thermal runaway event; The electronic controller identifies, from the plurality of coolant branches, the coolant branch associated with the battery module exhibiting the initiation of a thermal runaway event; and The electronic controller uses at least one flow valve to cut off the coolant flow to a coolant branch unrelated to the battery module exhibiting the onset of a thermal runaway event, thereby specifically cooling the battery module exhibiting the onset of a thermal runaway event and thus mitigating the TRP in the RESS.