A battery thermal management system and control method

Abstract

This application discloses a battery thermal management system and control method, relating to the field of battery thermal management technology. The battery thermal management system includes: a battery pack, comprising a heat insulation and fire suppression unit and multiple batteries independently isolated within the heat insulation and fire suppression unit; an active heat dissipation unit disposed on a first surface of the battery pack; and an active heating unit disposed on a second surface of the battery pack, the second surface being opposite or adjacent to the first surface; the two units can collaboratively regulate the temperature of each battery. This application achieves physical separation between batteries through the heat insulation and fire suppression unit, blocking lateral heat transfer under normal conditions and enabling rapid fire suppression protection in case of thermal runaway; combined with a bidirectional active temperature control structure, it achieves precise battery temperature regulation. This application balances battery normal temperature control efficiency and thermal runaway safety protection, featuring high integration, excellent space utilization, and effectively extending battery life, adapting to the needs of new energy vehicles and energy storage batteries.

Description

Technical Field

[0001] This application relates to the field of battery thermal management technology, and in particular to a battery thermal management system and control method. Background Technology

[0002] With the rapid development of new energy vehicles and energy storage technologies, the energy density of battery packs continues to increase, placing ever higher demands on the performance of battery thermal management systems. Batteries generate a large amount of heat during operation; inadequate heat dissipation can lead to localized overheating, affecting battery performance and lifespan. In low-temperature environments, battery activity decreases, requiring heating to restore its charge-discharge capacity. Meanwhile, the risk of battery thermal runaway remains a key concern in the industry. Once a single battery experiences thermal runaway, the heat can rapidly spread to adjacent batteries, potentially triggering a chain reaction and causing serious safety accidents.

[0003] In existing technologies, battery thermal management systems typically design temperature control and thermal runaway protection as separate functional modules. For temperature control, some solutions use liquid cooling systems to cool the entire battery pack, or heating films for overall heating. These solutions struggle to achieve precise temperature control at the battery level, and the cooling and heating functions are often independently configured, lacking coordination. Regarding thermal runaway protection, some solutions incorporate insulation layers within the battery pack to prevent heat spread, or fire extinguishing devices to suppress fires. However, insulation layers and fire extinguishing devices are usually arranged independently, occupying significant space and making rapid response difficult in the event of thermal runaway.

[0004] Furthermore, existing technologies lack a systematic solution that deeply integrates active temperature control with passive thermal insulation and fire suppression. The active temperature control module and the passive protection module lack a coordination mechanism, and temperature control operation may interfere with the protection effect. Simultaneously arranging temperature control and protection modules within the limited space of the battery pack leads to structural complexity and reduced energy density. Therefore, achieving synergy between efficient temperature control and reliable thermal runaway protection within the same system, while also considering structural compactness and safety, is a pressing technical problem that needs to be solved in this field. Summary of the Invention

[0005] This application discloses a battery thermal management system and control method to solve the technical problems of independent temperature control and protection functions, poor coordination, and low space utilization in related technologies.

[0006] To solve the above problems, this application adopts the following technical solution: In a first aspect, embodiments of this application provide a battery thermal management system, including: A battery pack, the battery pack including a heat-insulating fire extinguishing unit and multiple batteries filled inside the heat-insulating fire extinguishing unit and isolated from each other; An active heat dissipation unit is disposed on the first surface of the battery pack; An active heating unit is disposed on the second surface of the battery pack, the second surface being opposite to or adjacent to the first surface; The active heat dissipation unit and the active heating unit are configured to work together to control the temperature of the multiple batteries.

[0007] Secondly, embodiments of this application provide a battery thermal management control method, applied to the battery thermal management system described in the first aspect, comprising: Obtain temperature information inside the battery pack; When the temperature information is higher than the first preset threshold, the active heat dissipation unit is activated; When the temperature information is lower than the second preset threshold, the active heating unit is activated; Acquire thermal runaway parameters, wherein the thermal runaway parameters include at least one of voltage, pressure, or gas concentration; When the temperature information is detected to exceed the third preset threshold or the thermal runaway parameter exceeds the corresponding preset threshold, the fire extinguishing microcapsule is triggered to release the fire extinguishing agent. The third preset threshold is greater than the first preset threshold.

[0008] The technical solutions adopted in the embodiments of this application can achieve the following beneficial effects: (1) The battery thermal management system provided in this application embodiment integrates heat insulation material and fire extinguishing material into one unit by setting up a heat insulation and fire extinguishing unit. Multiple batteries are independently and isolated inside the heat insulation and fire extinguishing unit. At the same time, an active heat dissipation unit and an active heating unit are respectively set on the first surface and the second surface of the battery pack, and the first surface and the second surface are opposite or adjacent to each other. The active heat dissipation unit and the active heating unit work together to control the temperature of multiple batteries. The heat insulation and fire extinguishing unit blocks heat transfer between batteries under normal conditions and releases fire extinguishing agent in case of thermal runaway. The above structure enables the temperature control function and the protection function to be deeply integrated in the same system. The temperature control operation and the protection mechanism promote each other and realize system-level synergistic effect.

[0009] (2) The battery thermal management system provided in this application embodiment fills multiple batteries independently and isolated inside the heat insulation and fire extinguishing unit. Each battery is physically separated by heat insulation material, forming an independent thermal management unit. When any battery experiences thermal runaway, the heat insulation material in the heat insulation and fire extinguishing unit can effectively block the lateral transfer of heat, preventing the thermal runaway from spreading in a chain reaction between batteries. At the same time, the fire extinguishing material in the heat insulation and fire extinguishing unit can respond quickly when thermal runaway occurs, achieving precise suppression of the thermal runaway battery. The above structure cuts off the propagation path of thermal runaway inside the battery pack from the source, improving the overall safety of the system.

[0010] (3) The battery thermal management system provided in this application integrates the heat insulation function and the fire extinguishing function into the same heat insulation and fire extinguishing unit. The active heat dissipation unit and the active heating unit are attached to the outer surface of the battery pack in a plate-like structure. The overall structure is compact and does not require additional space to arrange independent protection modules. The above structural design is beneficial to improving the energy density of the battery pack and the system integration. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 yes Figure 1 Sectional view at point AA; Figure 3 yes Figure 1 Sectional view at point BB; Figure 4 yes Figure 3 Enlarged diagram of section C; Figure 5 This is an assembly diagram of an embodiment of this application; Figure 6 This is a schematic diagram showing the state of the battery installed in the heat insulation and fire extinguishing unit in an embodiment of this application; Figure 7 This is a top view of the intermediate shell in the embodiment of this application; Figure 8 This is a schematic diagram of the layout of the inner and outer insulation layers in the embodiments of this application.

[0013] In the diagram: 10, Battery pack; 101, Top cover; 102, Bottom cover; 103, Middle shell; 20, Active heat dissipation unit; 30, Active heating unit; 40, Heat insulation and fire extinguishing unit; 401, Heat insulation wall; 4011, Outer frame; 4012, Partition; 402, Fire extinguishing microcapsule layer; 403, Insulation layer; 50, Battery; 60, Upper elastic buffer layer; 70, Lower elastic buffer layer; 80, Upper busbar; 90, Lower busbar; 100, Positioning slot; 110, Annular gas collection gap; 120, One-way pressure relief valve; 130, Elastic damping protrusion; 140, Outer insulation layer; 150, Inner insulation layer. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0015] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such use of terms can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0016] Addressing the current industry needs in battery thermal management, where temperature control and thermal runaway protection are difficult to coordinate and system integration is insufficient, this application is based on the integrated design concept of full-domain thermal management and safety protection for battery packs. It deeply integrates active temperature control and passive heat insulation and fire extinguishing functions. By constructing a zoned independent battery insulation structure, coupled with directional heat conduction, layered temperature control, and real-time early warning protection mechanisms, it takes into account both precise temperature control under normal battery operating conditions and rapid emergency protection under thermal runaway conditions. At the same time, it optimizes the internal structural layout of the battery pack and modules, simplifies the pipeline and circuit layout, and improves thermal management efficiency and safety protection capabilities while increasing product integration and space utilization, adapting to the usage requirements of high energy density batteries.

[0017] Therefore, this application proposes a battery thermal management system and control method, which are described below in conjunction with the appendix. Figures 1 to 8 The battery thermal management related technical solutions provided in this application will be described in detail through specific embodiments and application scenarios. Example 1:

[0018] This embodiment provides a battery thermal management system, including a battery pack 10, an active heat dissipation unit 20, and an active heating unit 30.

[0019] The battery pack 10 includes a heat-insulating fire extinguishing unit 40 and multiple batteries 50 that are filled inside the heat-insulating fire extinguishing unit 40 and are independently isolated from each other. The heat-insulating fire extinguishing unit 40 is composed of heat-insulating material and fire-extinguishing material, and forms multiple independent battery cavities inside, with each battery 50 housed in its corresponding battery cavity, achieving physical isolation between the batteries 50. An active heat dissipation unit 20 is disposed on the first surface of the battery pack 10, and an active heating unit 30 is disposed on the second surface of the battery pack 10, with the first surface and the second surface facing each other. The active heat dissipation unit 20 and the active heating unit 30 work together to control the temperature of the multiple batteries 50, that is, based on the real-time temperature of the batteries 50, the active heat dissipation unit 20 is activated for cooling or the active heating unit 30 is activated for heating, so that the batteries 50 operate within a suitable temperature range.

[0020] In some embodiments, the battery thermal management system further includes a battery management unit, the battery management unit comprising: Multiple temperature sensors are distributed inside the battery pack 10 to collect temperature data of the multiple batteries 50; The controller is electrically connected to multiple temperature sensors, the active heat dissipation unit 20, and the active heating unit 30, respectively. The controller is configured to: The active heat dissipation unit 20 and the active heating unit 30 are controlled to turn on and off and adjust their power according to the temperature data. When the temperature of the battery 50 is detected to be higher than a first preset threshold, the active heat dissipation unit 20 is activated; when the temperature of the battery 50 is detected to be lower than a second preset threshold, the active heating unit 30 is activated, so that the temperature of the plurality of batteries 50 is maintained within a preset range. When the detected temperature data exceeds a third preset threshold, a thermal runaway warning signal is generated, where the third preset threshold is greater than the first preset threshold. It is understood that multiple temperature sensors distributed within the battery pack 10 can collect real-time temperature data across the entire battery pack 10. Combined with parameter sensors to synchronously monitor thermal runaway parameters, this allows for a comprehensive understanding of the internal operating conditions of the battery pack 10, enabling closed-loop precise control of the battery 50's temperature. The controller can autonomously activate and deactivate the active cooling and active heating modules and adjust their power based on real-time operating data. Specifically, when the temperature exceeds the first preset threshold, the active cooling unit 20 is activated; when the temperature falls below the second preset threshold, the active heating unit 30 is activated, ensuring that the battery 50 remains within a suitable operating temperature range. Simultaneously, it can promptly issue warning signals when abnormal temperatures are detected, prompting external monitoring systems or personnel to take safety measures. The fire extinguishing microcapsule employs a passive triggering mechanism. When the battery 50 experiences thermal runaway, the rapid increase in temperature within the battery cavity or the shock wave generated by the rupture of the battery 50's casing can cause the fire extinguishing microcapsule to rupture, releasing the internally encapsulated fire extinguishing agent to quickly and precisely suppress the thermal runaway battery 50.

[0021] In some embodiments, the battery management unit further includes at least one parameter sensor for collecting thermal runaway parameters, including at least one of voltage, pressure, or gas concentration; the controller is electrically connected to the parameter sensor, and the controller is further configured to generate a thermal runaway warning signal when the detected thermal runaway parameter exceeds a corresponding preset threshold. It is understood that by synchronously monitoring thermal runaway parameters through the parameter sensor, a comprehensive understanding of the internal operating conditions of the battery pack 10 can be obtained, allowing for timely detection of abnormal trends and issuance of warnings when thermal runaway occurs, further improving the intelligence level and responsiveness of the thermal management system, and comprehensively ensuring the operational stability and safety of the battery pack 10.

[0022] In some embodiments, the battery pack 10 includes a lower cover plate 102, an upper cover plate 101, and an intermediate shell 103 disposed between the lower cover plate 102 and the upper cover plate 101; the lower cover plate 102, the upper cover plate 101, and the intermediate shell 103 are sealed together to form a receiving cavity; the heat-insulating fire extinguishing unit 40 and the plurality of batteries 50 are housed within the receiving cavity. It is understood that the sealed encapsulation structure of the upper cover plate 101 and the intermediate shell 103, together forming a sealed receiving cavity, provides a stable mounting carrier for the internal heat-insulating fire extinguishing unit 40 and batteries 50, enabling the orderly arrangement of various components, and also improves the overall sealing and protection performance of the battery pack 10, preventing the intrusion of external moisture, dust, and other impurities, ensuring a stable internal thermal management environment. Simultaneously, the integrated sealed cavity structure strengthens the overall structural strength of the battery pack 10 and optimizes the internal space layout.

[0023] In some embodiments, the upper cover 101 and the lower cover 102 are made of thermally conductive metal materials, preferably aluminum alloy or copper alloy. Thermally conductive metal materials have a high thermal conductivity coefficient, enabling efficient transfer of heat generated during battery 50 operation to the active heat dissipation unit 20 disposed on the outer surface of the upper cover 101, or uniform transfer of heat generated by the active heating unit 30 to the battery 50. Furthermore, aluminum alloys offer both good thermal conductivity and lightweight advantages, which is beneficial for improving the energy density of the battery pack 10; copper alloys have higher thermal conductivity and are suitable for applications with high heat dissipation requirements. The mating surfaces of the upper cover 101 and lower cover 102, which are sealed to the intermediate housing 103, can be provided with gaskets or coated with sealant to ensure the sealing of the cavity.

[0024] In some embodiments, the heat-insulating fire extinguishing unit 40 includes: A heat insulation wall 401 is disposed in the receiving cavity. The heat insulation wall 401 constitutes a plurality of battery cavities adapted to the battery 50. The plurality of batteries 50 are arranged in an array and respectively housed in the corresponding battery cavities to achieve independent isolation between each battery 50. An insulating layer 403 is disposed on the inner wall surface of the battery cavity and continuously covers the battery cavity in the circumferential and axial directions to prevent electrical contact between the battery 50 casing and the heat insulation wall 401. The insulating layer 403 is made of a thermally conductive insulating material, preferably a thermally conductive ceramic coating, a thermally conductive insulating adhesive, or a thermally conductive plastic, to ensure that electrical isolation is achieved without hindering heat conduction. Fire extinguishing microcapsules are disposed on the surface of the insulating layer 403, located on the inner wall of the battery cavity. It is understood that the heat insulation wall 401 divides the housing cavity into multiple independent battery cavities, with each battery 50 independently housed in its corresponding cavity, achieving physical isolation between the batteries 50. The insulating layer 403, as a base layer, continuously covers the entire sidewall surface of the battery cavity and is made of thermally conductive insulating material. This completely isolates the battery 50's casing from the heat insulation wall 401, avoiding the risk of short circuits due to insulation failure, while also ensuring efficient heat conduction between the battery 50 and the heat insulation wall 401 without disrupting the overall heat conduction path. The fire extinguishing microcapsules, disposed on the surface of the insulating layer 403, can rupture when thermal runaway occurs. A rapid increase in temperature within the battery cavity or a shock wave generated by the rupture of the battery 50's casing can cause the fire extinguishing microcapsules to release the encapsulated fire extinguishing agent, enabling rapid and precise suppression of thermal runaway batteries 50. By integrating the heat insulation wall 401, the insulation layer 403, and the fire extinguishing microcapsule into the same unit, each battery 50 is provided with an independent electrical insulation protection and thermal runaway protection mechanism. This not only avoids the spatial redundancy caused by the separate setting of the heat insulation layer and the fire extinguishing device in the traditional solution, but also improves the timeliness and targeting of the thermal runaway response.

[0025] In some embodiments, the heat insulation wall 401 includes: The outer frame is 4011, and it is a cuboid shape with open ends; Multiple partitions 4012 are disposed inside the outer frame 4011. The multiple partitions 4012 are crisscrossed and connected to the inner wall of the outer frame 4011, dividing the interior of the outer frame 4011 into multiple battery cavities arranged in an array. The outer frame 4011 and multiple separators 4012 are integrally formed. It is understood that the integrally formed structure of the outer frame 4011 and separators 4012 avoids the stress concentration and weakness issues caused by the connection interfaces in a split structure. The internally arranged, crisscrossing separators 4012 connect to the outer frame 4011, dividing the internal space into multiple independent battery cavities, forming an isolated architecture of "one battery 50, one battery cavity". This ensures physical isolation between the battery cavities and achieves unified overall structural strength and assembly stability through continuous material distribution, which is beneficial to improving the reliability and manufacturing yield of the battery pack 10.

[0026] In some embodiments, the battery pack 10 further includes a pressure relief buffer structure. At least one one-way pressure relief valve 120 is provided on the side wall of the intermediate housing 103. The one-way pressure relief valve 120 communicates with the receiving cavity and is used to unilaterally discharge gas when the pressure in the receiving cavity exceeds a preset opening pressure. The partition 4012 of the heat insulation wall 401 is provided with pressure relief micropores penetrating adjacent battery cavities, and the outer frame 4011 is provided with pressure relief micropores penetrating the gap between the battery cavity and the inner wall of the intermediate housing 103. Optionally, the pressure relief micropores are filled with fire-extinguishing microcapsules to instantly cool and suppress the discharged gas, preventing high-temperature gas from causing secondary combustion externally. For application scenarios with low external environmental risk, fire-extinguishing microcapsules at the pressure relief micropores may not be provided, and thermal runaway suppression can be achieved solely by fire-extinguishing microcapsules on the inner wall of the battery cavity. An annular gas collection gap 110 is formed between the outer frame 4011 and the inner wall of the intermediate housing 103. The pressure relief microhole is connected to the annular gas collection gap 110, and the annular gas collection gap 110 is connected to the one-way pressure relief valve 120.

[0027] Optionally, a one-way valve assembly may be provided between the annular gas collecting gap 110 and the one-way pressure relief valve 120. The one-way valve assembly is used to open when the pressure in the annular gas collecting gap 110 reaches a first pressure threshold (exemplarily, 0.05MPa to 0.1MPa) to achieve staged pressure relief, reduce the peak pressure in the battery cavity, and provide more time for gas cooling. For application scenarios with low risk of thermal runaway, the one-way valve assembly may not be provided, and single-stage pressure relief may be achieved solely by the one-way pressure relief valve 120.

[0028] Understandably, when a single battery 50 experiences thermal runaway, high-temperature, high-pressure gas is rapidly generated within its battery cavity. This gas releases pressure to adjacent battery cavities through the pressure relief micropores on the separator 4012 (if filled with fire-extinguishing microcapsules, the microcapsules in adjacent battery cavities rupture synchronously, forming a synergistic suppression). Simultaneously, it enters the annular gas collection gap 110 through the pressure relief micropores on the outer frame 4011. If a one-way valve assembly is provided, it opens when the pressure within the annular gas collection gap 110 reaches a first pressure threshold, allowing the gas to enter subsequent channels and ultimately be discharged to the outside of the battery pack 10 via the one-way pressure relief valve 120. During this process, if the pressure relief micropores are filled with fire-extinguishing microcapsules, the high-pressure gas triggers the microcapsules to rupture, releasing a fire-extinguishing agent to cool and suppress the high-temperature gas, preventing direct discharge and secondary combustion. The annular gas collection gap 110 acts as a gas buffer chamber, reducing the velocity and pressure peak of the ejected gas, preventing damage to the one-way pressure relief valve 120 or the overall structure of the battery pack 10 due to instantaneous high-pressure impact. By setting up a pressure relief buffer structure, the directional drainage and cooling of thermal runaway gas is achieved. While maintaining the physical and thermal isolation of each battery cavity, the problem of casing rupture or thermal spread to adjacent batteries that may be caused by the accumulation of high pressure gas is effectively solved, further improving the safety of battery pack 10.

[0029] In some embodiments, the pressure-relief micropores are normally open micropores with a diameter of 0.5 mm to 2 mm, integrally molded with the heat insulation wall 401. During the molding process, the pressure-relief micropores are formed by a micro-core set in the mold. After the gel solidifies, the core is first removed and then demolded to avoid structural damage to the graphene aerogel material during secondary processing. The pressure-relief micropores penetrate the partition plate 4012 and the outer frame 4011 along their respective thickness directions, and are arranged in an array on both the partition plate 4012 and the outer frame 4011, with a center-to-center distance of 5 mm to 15 mm between adjacent pressure-relief micropores.

[0030] Optionally, depending on the energy density and gas production of the battery pack 10, the pore size of the pressure relief micropores can be adjusted within the range of 0.5mm to 2.0mm: for high-energy-density battery packs 10 with a large gas production, a pore size of 1.5mm to 2.0mm and a smaller number of pores are preferred; for applications with extremely high structural strength requirements, a pore size of 0.5mm to 1.0mm and a larger number of pores are preferred.

[0031] In some embodiments, the inner wall of the pressure relief micropore is coated with a high-temperature resistant insulating coating; Please see Figure 8In some embodiments, the outer peripheral wall of the outer frame 4011 and the inner wall of the intermediate housing 103 are respectively provided with an outer insulating layer 150 and an inner insulating layer 140. Furthermore, the arrangement path of the pressure relief channel of the battery pack 10 needs to maintain a safe distance from the tabs and busbars of the battery 50 to prevent high-temperature gas or ionized particles from being ejected towards the electrical connection points and causing a short circuit. The path of the pressure relief channel is as follows: battery cavity → pressure relief micro-holes on the outer frame 4011 → annular gas collection gap 110 → one-way pressure relief valve 120 → outside of the battery pack 10. It is understood that through the above electrical insulation measures, high-pressure gas and live components are effectively isolated during the pressure relief process, ensuring that the pressure relief action does not introduce new electrical safety risks.

[0032] In some embodiments, the battery cavity is further provided with an elastic limiting member for fixing the battery 50; the elastic limiting member is a plurality of elastic damping protrusions 130 protruding from the inner wall of the battery cavity, the elastic damping protrusions 130 are evenly distributed along the circumference of the battery cavity and are elastically interference-fitted with the outer wall of the battery 50. The elastic damping protrusions 130 and the fire extinguishing microcapsules are staggered on the surface of the insulating layer 403, avoiding each other in space. Specifically, along the circumference of the battery cavity, the areas where the elastic damping protrusions 130 and the fire extinguishing microcapsules are placed are spaced apart; along the axial direction of the battery cavity, the areas where the elastic damping protrusions 130 and the fire extinguishing microcapsules are placed can also be layered. The fire extinguishing microcapsules are attached to a predetermined area on the surface of the insulating layer 403 in the form of a coating to form a fire extinguishing microcapsule layer 402, which can be achieved by spraying, dipping, or brushing. The elastic damping protrusions 130 are disposed in the blank areas adjacent to the surface of the insulating layer 403, and the protrusion height of the elastic damping protrusions 130 is greater than the coating thickness of the fire extinguishing microcapsule. The elastic damping protrusions 130 are made of materials with good elasticity, temperature resistance and thermal conductivity, preferably thermally conductive silicone rubber, thermally conductive fluororubber or foamed polyurethane with added thermally conductive filler, and can be fixed to the surface of the insulating layer 403 by secondary injection molding, dispensing or pasting.

[0033] Understandably, when the battery 50 is inserted into the cavity, the elastic damping protrusion 130 preferentially contacts the outer wall of the battery 50 and provides pre-tightening force, while the fire extinguishing microcapsule layer 402 is not compressed. This ensures the stable fixation of the battery 50 while effectively protecting the structural integrity of the fire extinguishing microcapsule. The thermal conductivity of the elastic damping protrusion 130 ensures a smooth heat conduction path between the battery 50 and the cavity wall, avoiding a decrease in temperature control efficiency due to the fixing structure obstructing heat transfer. Compared to surface contact fixing, this point-contact fixing method reduces the contact area between the fixing structure and the battery 50, which is beneficial for heat dissipation on the surface of the battery 50. Furthermore, the elastic element's buffering effect absorbs vibration energy, preventing damage to the battery 50 casing that might occur with rigid fixing. Simultaneously, the elastic damping protrusion 130 and the fire extinguishing microcapsule are staggered on the inner wall of the cavity, their functions do not interfere with each other, and together they improve the operational stability of the battery 50 within the cavity.

[0034] In some embodiments, the heat insulation wall 401 is made of anisotropic graphene aerogel material. The thermal conductivity of the anisotropic graphene aerogel in the vertical direction (up-down direction) is greater than its thermal conductivity in the horizontal direction (planar direction), so that heat is preferentially conducted along the vertical direction. It can be understood that by using anisotropic graphene aerogel to prepare the heat insulation wall 401, the inherent directional thermal conductivity of the material itself can be used to achieve directional heat dissipation of the battery 50. Combined with the structural layout of this application, in which the active heat dissipation unit 20 and the active heating unit 30 are respectively located on opposite or adjacent surfaces of the battery pack 10, the heat generated by the battery 50 during operation can be preferentially and quickly conducted along the vertical direction to the corresponding active heat dissipation unit 20 or active heating unit 30, ensuring that the heat dissipation process of the battery 50 and the external heat introduction process are efficient and smooth, and maintaining the precise and controllable temperature of the battery 50. Meanwhile, this material can significantly reduce horizontal heat transfer between batteries 50, blocking lateral heat accumulation inside the battery pack 10 and preventing mutual interference between batteries. While ensuring overall heating and heat dissipation efficiency, it continuously maintains thermal isolation between batteries 50, balancing the normal temperature control efficiency of the battery pack 10 with thermal runaway protection safety, achieving a balance between temperature control performance and safety protection. Furthermore, anisotropic graphene aerogel materials inherently possess a certain degree of brittleness. The one-piece molding design of the heat insulation wall 401 allows the entire heat insulation wall 401 to form a continuous and complete skeletal structure, avoiding the risk of breakage due to uneven local stress.

[0035] In some embodiments, the heat insulation wall 401 is fixed to the intermediate shell 103 in the following ways: horizontal fixing: the inner wall of the intermediate shell 103 is provided with a positioning structure, and the outer peripheral wall of the outer frame 4011 cooperates with the positioning structure to limit the displacement of the heat insulation wall 401 in the horizontal direction. The outer frame 4011 serves as a support frame for the overall structure and cooperates with the positioning structure of the intermediate shell 103 to achieve reliable horizontal fixing; vertical fixing: the upper cover plate 101 and the lower cover plate 102 abut against the upper and lower end faces of the outer frame 4011 and the partition plate 4012, respectively, to fix the heat insulation wall 401 in the vertical direction.

[0036] In some embodiments, the positioning structure is a positioning groove 100 integrally formed along the circumferential inner wall of the intermediate shell 103. The shape of the inner wall of the positioning groove 100 is adapted to the shape of the outer wall of the outer frame 4011 of the heat insulation wall 401, and the two are fitted with a clearance to achieve snap-fit ​​positioning. The positioning groove 100 is evenly distributed along the inner wall of the intermediate shell 103, and the groove contact surface is flat and smooth. It can not only form a precise horizontal limit for the outer frame 4011 of the heat insulation wall 401, effectively constraining the lateral displacement of the heat insulation wall 401, but also facilitate the rapid pre-installation and positioning of the heat insulation wall 401, simplifying the overall assembly process. During the assembly process, the heat insulation wall 401 body will not be scratched or damaged, fully ensuring the structural integrity and installation stability of the heat insulation wall 401.

[0037] In some embodiments, the battery pack 10 further includes a buffer unit comprising an upper elastic buffer layer 60 and a lower elastic buffer layer 70; the upper elastic buffer layer 60 is disposed between the upper cover plate 101 and the upper end face of the outer frame 4011 and the partition plate 4012; the lower elastic buffer layer 70 is disposed between the lower cover plate 102 and the lower end face of the outer frame 4011 and the partition plate 4012; the upper elastic buffer layer 60 and the lower elastic buffer layer 70 are used to buffer clamping force and absorb vibration impact; The first surface is the outer surface of the upper cover plate 101, and the second surface is the outer surface of the lower cover plate 102. The active heat dissipation unit 20 and the active heating unit 30 are respectively fixed to the first surface and the second surface by fasteners or adhesive layers. The upper elastic buffer layer 60 and the lower elastic buffer layer 70 are made of insulating and thermally conductive material. This insulating and thermally conductive material is used on the one hand to establish a heat conduction path between the heat insulation wall 401 and the upper cover plate 101, and between the heat insulation wall 401 and the lower cover plate 102, and on the other hand to isolate the upper cover plate 101 and the lower cover plate 102 from the tabs and busbars of the battery 50 to prevent the risk of short circuit caused by electrical contact. Understandably, adding an elastic buffer layer that combines insulation and thermal conductivity can buffer the clamping force of the cover plate and absorb external vibration impact during assembly and use, reduce the risk of component damage, and improve the overall vibration resistance and durability of the battery pack 10. It can also build a stable vertical heat conduction path based on the thermal conductivity of the material, ensuring efficient heat conduction during active heat dissipation and active heating. At the same time, its insulation properties can achieve electrical isolation between the tabs and the metal upper cover plate 101 and the metal lower cover plate 102, avoiding the risk of short circuits. It takes into account both structural protection and temperature control conduction, further optimizing the operational stability of the thermal management system.

[0038] In some embodiments, the outer peripheral wall of the outer frame 4011 is covered with a flexible protective layer, which contacts the inner wall of the positioning structure to prevent the outer frame 4011 from breaking due to direct contact. It is understood that adding a flexible protective layer to the outside of the outer frame 4011 can isolate the frame from direct hard contact with the positioning structure, reduce frictional wear and crushing damage during assembly and long-term use, avoid the risk of frame breakage and failure of the heat insulation wall 401, extend the service life of the heat insulation and fire extinguishing unit 40, and at the same time, not affect the horizontal positioning and limiting effect, ensuring the overall installation stability of the heat insulation wall 401 and maintaining the long-term stable operation of the internal structure of the battery pack 10. Given that the heat insulation wall 401 is made of anisotropic graphene aerogel material, which has a certain degree of brittleness, multiple protective measures are adopted in the fixing structure: In the horizontal direction, by covering the outer perimeter of the outer frame 4011 with a flexible protective layer, the direct hard contact between the outer frame 4011 and the positioning structure is isolated, avoiding frictional wear and crushing damage during assembly and vibration; In the vertical direction, by setting an upper elastic buffer layer 60 and a lower elastic buffer layer 70 between the upper cover plate 101 and the heat insulation wall 401, and between the lower cover plate 102 and the heat insulation wall 401, respectively, the clamping force of the upper cover plate 101 and the lower cover plate 102 is evenly distributed, absorbing external vibration impact and avoiding the risk of breakage caused by uneven local stress. This dual fixing method, combining horizontal positioning with vertical clamping, along with the synergistic effect of the flexible protective layer and the elastic buffer layer, can comprehensively limit the displacement space of the heat insulation wall 401. While ensuring installation stability, it effectively protects the structural integrity of brittle materials. Even under long-term vibration conditions, the heat insulation wall 401 can maintain structural stability, ensuring the continuous and stable operation of the battery 50's separation, heat insulation, and fire extinguishing functions. Furthermore, it eliminates the need for additional complex fasteners, does not occupy extra internal space in the battery pack 10, and further ensures the overall compactness and ease of assembly of the battery pack 10.

[0039] In some embodiments, the fire extinguishing microcapsule comprises a shell wall and a fire extinguishing core material encapsulated within the shell wall. The shell wall material can be selected from at least one of thermoplastic resin, urea-formaldehyde resin, or melamine resin, and its melting point or rupture temperature is preset to be higher than the third preset threshold, i.e., higher than the thermal runaway warning temperature threshold. When the temperature inside the battery cavity further rises to this preset value, the shell wall softens or ruptures, releasing the internal fire extinguishing core material. The fire extinguishing core material is preferably perfluorohexanone, which is liquid at room temperature and can rapidly absorb a large amount of heat after vaporization. At the same time, it interrupts the combustion chain reaction through chemical inhibition, thus having both cooling and fire extinguishing effects. By setting the melting point or rupture temperature of the fire extinguishing microcapsule shell wall to be higher than a third preset threshold, the microcapsule maintains its structural integrity during both the normal temperature control stage and the thermal runaway warning stage. It is only passively activated when the thermal runaway deteriorates to a critical state (the temperature continues to rise to the rupture point or is subjected to a shock wave). This avoids false release caused by temperature fluctuations or early warning of thermal runaway. In conjunction with the aforementioned graded response mechanism, it achieves the technical effect of graded protection and precise fire extinguishing with "early warning first, fire extinguishing later".

[0040] In some embodiments, the active heat dissipation unit 20 includes a condenser plate with a condenser tube inside. The inlet and outlet of the condenser tube are connected to an external cooling circulation system. It is understood that using a condenser plate with built-in condenser tubes as an active heat dissipation component, in conjunction with an external cooling circulation system, can form a closed-loop heat dissipation path. This can evenly remove the heat generated by the battery 50 during operation, achieving efficient heat dissipation throughout the battery pack 10, ensuring a stable and balanced internal temperature field. Furthermore, the close-fitting arrangement of the condenser plate provides a large heat dissipation contact area and high heat dissipation efficiency, adapting to the high-power heat dissipation requirements of the high-energy-density battery pack 10 and maintaining the stable operating state of the battery 50.

[0041] In some embodiments, the condenser tubes are arranged in a serpentine or parallel configuration inside the condenser plate. The serpentine arrangement of the condenser tubes involves a single pipe repeatedly bending within the condenser plate to form a continuous flow channel covering the entire condenser plate. This arrangement offers advantages such as simple structure, fewer joints, and low leakage risk, making it suitable for applications with high reliability requirements. The parallel arrangement of the condenser tubes consists of multiple parallel straight pipes, each connected to a manifold at both ends. The coolant flows in parallel within each straight pipe, offering advantages such as low flow resistance and good heat exchange uniformity, making it suitable for applications with high heat dissipation efficiency requirements. In practical applications, a suitable condenser tube arrangement can be selected based on the battery pack's heating power, temperature uniformity requirements, and space constraints. Alternatively, a combination of serpentine and parallel arrangements can be used to achieve a balance between heat dissipation performance and structural compactness.

[0042] In some embodiments, the active heating unit 30 includes an electric heating film, which has a heating circuit internally connected to an external temperature control circuit. It is understood that using an electric heating film with a built-in heating circuit as an active heating component allows for flexible adjustment of heating power via an external temperature control circuit. This enables rapid and uniform heating of the battery pack 10 in low-temperature environments, quickly restoring the charge / discharge activity of the battery 50. Furthermore, the electric heating film is thin and lightweight with high adhesion, without occupying additional installation space in the battery pack 10, further improving system integration and adapting to the heating needs of the battery 50 under various operating conditions.

[0043] In some embodiments, the electric heating film includes a polyimide heating film, a silicone heating film, or a metal foil heating film.

[0044] In some embodiments, the heating circuitry is uniformly distributed within the electric heating film, forming a planar heating source. The heating circuitry can be formed by etching metal foil or printing conductive ink. Through the density distribution design of the circuit wiring, a uniform heating area is formed within the electric heating film. Compared to linear or point-like heating sources, planar heating sources can provide a larger heating area and a more uniform temperature distribution, avoiding performance degradation or safety risks to the battery 50 due to localized overheating. The heating circuitry is electrically connected to an external temperature control circuit. The external temperature control circuit can control the output power of the heating circuitry through pulse width modulation or power regulation based on the battery 50 temperature data collected by the temperature sensor, achieving precise control of the heating process of the battery pack 10.

[0045] In some embodiments, multiple batteries 50 are electrically connected via busbars, forming at least one of series connection, parallel connection, or series-parallel hybrid connection. Specifically, the busbar includes an upper busbar 80 and a lower busbar 90; the upper busbar 80 and the lower busbar 90 are respectively disposed above and below the tabs of the batteries 50, for realizing parallel, series, or series-parallel hybrid electrical connections of multiple batteries 50 at the circuit level. It is understood that the batteries 50 achieve various flexible circuit connection methods through the busbars, adapting to different voltage and current output conditions according to actual usage needs, improving the scenario adaptability and usage flexibility of the battery pack 10. The busbar is disposed at the tab connection end of the battery 50, electrically connected to the tabs of the battery 50, and routed above or below the heat insulation wall 401, without damaging the independent isolation structure of each battery cavity. The busbar has strong conductivity stability, ensuring smooth current transmission between batteries 50, reducing circuit losses, and improving the overall power supply stability of the battery pack 10. As mentioned above, the upper busbar 80 and the upper cover plate 101 are electrically isolated by the upper elastic buffer layer 60, and the lower busbar 90 and the upper surface of the heat insulation wall 401 are electrically isolated by the lower elastic buffer layer 70, ensuring electrical safety in high-voltage and high-integration application scenarios. Example 2:

[0046] This embodiment provides a battery thermal management control method, which is applied to the battery thermal management system described in Embodiment 1, and specifically includes the following steps: Step S1: Obtain the temperature information inside the battery pack 10.

[0047] By deploying multiple temperature sensors inside the battery pack 10, the temperature data of each battery 50 is collected in real time, enabling real-time monitoring of the temperature conditions throughout the battery pack 10 and providing data support for subsequent temperature control.

[0048] Step S2: When the temperature information is higher than the first preset threshold, the active heat dissipation unit 20 is activated.

[0049] The controller receives real-time temperature data transmitted by the temperature sensor. When the temperature of the battery 50 is detected to be higher than the first preset threshold, the controller immediately starts the active heat dissipation unit 20. Specifically, it controls the external cooling circulation system to be turned on, so that the coolant is continuously introduced into the condenser tube inside the condenser plate. Through the circulation of the coolant, the heat generated by the operation of the battery 50 is continuously removed, and the temperature of the battery 50 is kept within the normal operating range.

[0050] Step S3: When the temperature information is lower than the second preset threshold, the active heating unit 30 is activated.

[0051] When the controller detects that the temperature of the battery 50 is lower than the second preset threshold, it immediately activates the active heating unit 30. Specifically, it connects the heating circuit inside the electric heating film, generates heat through the heating circuit, and uniformly heats the battery 50 inside the battery pack 10, quickly raising the temperature of the battery 50 to restore it to the normal charging and discharging operating temperature, thus ensuring the working performance of the battery 50 in low-temperature environments.

[0052] Step S4: When the detected temperature exceeds the third preset threshold, a thermal runaway warning signal is generated.

[0053] The controller receives temperature data. When the temperature of battery 50 exceeds the third preset threshold, it determines that battery 50 has experienced thermal runaway. The controller generates a thermal runaway warning signal to prompt external monitoring systems or personnel to take safety measures.

[0054] In this embodiment, the third preset threshold is greater than the first preset threshold, meaning the thermal runaway warning temperature threshold is higher than the normal heat dissipation start-up temperature threshold, thus forming a graded response mechanism in temperature control: when the temperature of battery 50 is between the first and third preset thresholds, the active heat dissipation unit 20 performs normal temperature control adjustment; when the temperature of battery 50 exceeds the third preset threshold, it indicates that battery 50 has entered a thermal runaway state, and the controller issues a warning signal. This graded setting clearly distinguishes between normal temperature control and thermal runaway warning, avoiding false warnings caused by temperature fluctuations under normal heat dissipation conditions.

[0055] The fire extinguishing microcapsule employs a passive triggering mechanism, with the melting point or rupture temperature of its shell material set above a third preset threshold. When battery 50 experiences thermal runaway and the temperature continues to rise to the shell rupture temperature, or when the shock wave generated by the rupture of battery 50 acts on the fire extinguishing microcapsule, the microcapsule passively ruptures, releasing the encapsulated perfluorohexanone fire extinguishing agent. This rapidly suppresses the thermal runaway battery 50 and blocks the spread of thermal runaway. It is understood that by setting the rupture temperature of the fire extinguishing microcapsule above the warning temperature threshold, it ensures that the microcapsule is only activated when thermal runaway deteriorates to a critical state, avoiding accidental release due to temperature fluctuations in the early stages of thermal runaway or during normal temperature control, thus achieving the technical effects of graded protection and precise fire extinguishing.

[0056] In some embodiments, the battery thermal management control method further includes: Acquire thermal runaway parameters. Thermal runaway parameters inside the battery pack 10 are collected in real time by parameter sensors. Thermal runaway parameters include at least one of voltage, pressure, and gas concentration. Specifically, the rate of change of battery voltage 50, the gas pressure value inside the battery pack 10 cavity, and the concentration of electrolyte volatile gases can be monitored in real time to comprehensively predict the risk of thermal runaway of battery pack 10.

[0057] When a thermal runaway parameter is detected to exceed a corresponding preset threshold, a thermal runaway warning signal is generated. When any parameter—the rate of voltage drop of battery 50, the internal pressure of battery pack 10, or the concentration of leaked gas—exceeds its corresponding preset threshold, the controller generates a thermal runaway warning signal to alert external monitoring systems or personnel to take safety measures in advance. It is understandable that by adding monitoring and warning functions for thermal runaway parameters, abnormal trends can be detected and warnings issued in a timely manner before thermal runaway occurs, further improving the intelligence and responsiveness of the thermal management system and comprehensively ensuring the operational stability and safety of battery pack 10.

[0058] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0059] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0060] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A battery thermal management system, characterized in that, include: A battery pack, the battery pack including a heat-insulating fire extinguishing unit and multiple batteries filled inside the heat-insulating fire extinguishing unit and isolated from each other; An active heat dissipation unit is disposed on the first surface of the battery pack; An active heating unit is disposed on the second surface of the battery pack, the second surface being opposite to or adjacent to the first surface; The active heat dissipation unit and the active heating unit are configured to work together to control the temperature of the multiple batteries.

2. The battery thermal management system according to claim 1, characterized in that, The battery thermal management system further includes a battery management unit, which includes: Multiple temperature sensors are distributed inside the battery pack to collect temperature data of the multiple batteries; The controller is electrically connected to multiple temperature sensors, the active heat dissipation unit, and the active heating unit, respectively. The controller is configured to: The active cooling unit and the active heating unit are controlled to turn on and off and adjust their power according to the temperature data. When the battery temperature is detected to be higher than a first preset threshold, the active cooling unit is activated; when the battery temperature is detected to be lower than a second preset threshold, the active heating unit is activated so that the temperature of the multiple batteries is maintained within a preset range. When the temperature data is detected to exceed a third preset threshold, a thermal runaway warning signal is generated, wherein the third preset threshold is greater than the first preset threshold.

3. The battery thermal management system according to claim 2, characterized in that, The battery management unit further includes at least one parameter sensor for collecting thermal runaway parameters, which include at least one of voltage, pressure, or gas concentration; the controller is electrically connected to the parameter sensor and is further configured to generate a thermal runaway warning signal when the thermal runaway parameter is detected to exceed a corresponding preset threshold. And / or, the battery pack includes: Lower cover plate; The upper cover plate is disposed opposite to the lower cover plate; An intermediate housing is disposed between the lower cover plate and the upper cover plate, and is sealed to the lower cover plate and the upper cover plate to form a receiving cavity; The heat-insulating fire extinguishing unit and the plurality of batteries are housed within the housing cavity.

4. The battery thermal management system according to claim 3, characterized in that, The heat-insulating fire extinguishing unit includes: A heat insulation wall is disposed within the receiving cavity. The heat insulation wall forms multiple battery cavities adapted to the battery. The multiple batteries are arranged in an array and respectively housed in the corresponding battery cavities to achieve independent isolation between each battery. An insulating layer is disposed on the inner wall surface of the battery cavity, continuously covering the circumference and axial direction of the battery cavity, and the insulating layer is made of a thermally conductive insulating material; Fire extinguishing microcapsules are disposed on the surface of the insulating layer and located on the inner wall of the battery cavity.

5. The battery thermal management system according to claim 4, characterized in that, The battery cavity is also provided with an elastic limiting member for fixing the battery; the elastic limiting member is a plurality of elastic damping protrusions protruding from the inner wall of the battery cavity, the elastic damping protrusions are evenly distributed along the circumference of the battery cavity and are interference fit with the outer wall of the battery; the elastic damping protrusions and the fire extinguishing microcapsule are staggered on the inner wall of the battery cavity, and the two avoid each other in space. And / or, the insulation wall comprises: The outer frame is a rectangular parallelepiped shape with openings at both ends; Multiple partitions are disposed inside the outer frame. The multiple partitions are crisscrossed and connected to the inner wall of the outer frame, dividing the interior of the outer frame into multiple battery cavities arranged in an array. The outer frame is integrally formed with multiple partitions.

6. The battery thermal management system according to claim 5, characterized in that, The thermal insulation wall is made of anisotropic graphene aerogel material, and the thermal conductivity of the anisotropic graphene aerogel in the vertical direction is greater than its thermal conductivity in the horizontal direction. And / or, the heat insulation wall is fixed within the intermediate housing in the following manner: Horizontal fixation: The inner wall of the intermediate shell is provided with a positioning structure, and the outer peripheral wall of the outer frame cooperates with the positioning structure to limit the displacement of the heat insulation wall in the horizontal direction; Vertical fixing: The upper cover plate and the lower cover plate respectively press against the upper and lower end surfaces of the outer frame and the partition to clamp and fix the heat insulation wall in the vertical direction.

7. The battery thermal management system according to claim 6, characterized in that, The fire extinguishing microcapsules are attached to the inner wall surface of the battery cavity, or embedded inside the heat insulation wall and exposed to the inner wall surface of the battery cavity; And / or, the outer peripheral wall of the outer frame is covered with a flexible protective layer, which is in contact with the inner wall of the positioning structure.

8. The battery thermal management system according to claim 8, characterized in that, The battery pack further includes a buffer unit, which includes an upper elastic buffer layer and a lower elastic buffer layer; the upper elastic buffer layer is disposed between the upper cover plate and the upper end face of the outer frame and the partition plate; the lower elastic buffer layer is disposed between the lower cover plate and the lower end face of the outer frame and the partition plate. The first surface is the outer surface of the upper cover plate, the second surface is the outer surface of the lower cover plate, and the active heat dissipation unit and the active heating unit are respectively fixed to the first surface and the second surface by fasteners or adhesive layers; the upper elastic buffer layer and the lower elastic buffer layer are made of insulating and thermally conductive materials.

9. The battery thermal management system according to claim 1, characterized in that, The active heat dissipation unit includes a condenser plate, and a condenser tube is provided inside the condenser plate. The inlet and outlet of the condenser tube are respectively connected to an external cooling circulation system. And / or, the active heating unit includes an electric heating film, the electric heating film having a heating circuit inside, and the heating circuit being electrically connected to an external temperature control circuit; And / or, multiple batteries are connected by busbars to form at least one of series connection, parallel connection or series-parallel hybrid connection.

10. A battery thermal management control method, applied to the battery thermal management system according to any one of claims 1 to 9, characterized in that, include: Obtain temperature information inside the battery pack; When the temperature information is higher than the first preset threshold, the active heat dissipation unit is activated; When the temperature information is lower than the second preset threshold, the active heating unit is activated; When the detected temperature exceeds a third preset threshold, a thermal runaway warning signal is generated. The third preset threshold is greater than the first preset threshold.

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