Battery pack provided with spontaneous combustion protection device, vehicle and battery spontaneous combustion protection method

Abstract

The invention discloses a battery pack provided with a spontaneous combustion protection device, a vehicle and a battery spontaneous combustion protection method, and relates to the technical field of battery protection. The battery pack comprises: a reaction liquid release assembly; the reaction liquid release assembly is arranged in the battery pack; when the internal temperature of the battery pack reaches the spontaneous combustion critical temperature, the reaction liquid release assembly is used for releasing specific flame-retardant reaction liquid; the specific flame-retardant reaction liquid has the characteristics that a chemical reaction is carried out at a spontaneous combustion critical temperature to generate a target protection substance capable of isolating air, and the target protection substance is attached to a target area of the battery pack. The reaction liquid release assembly is arranged in the battery pack, and when the internal temperature of the battery pack reaches the spontaneous combustion critical temperature, the reaction liquid release assembly releases the flame-retardant reaction liquid to generate the target protection substance for isolating air to be attached to the target area of the battery pack, so that thermal diffusion of the battery is effectively restrained from the interior of the battery; the spontaneous combustion risk of the battery is reduced.

Description

Technical Field

[0001] The present application relates to the field of battery protection technology, and in particular to a battery pack provided with a spontaneous combustion protection device, a vehicle, and a battery spontaneous combustion protection method. Background Art

[0002] With the increasing popularity of electric vehicles, the safety of their power batteries has drawn considerable attention. Power battery fires are difficult to extinguish and often lead to serious consequences. Current efforts to prevent power battery spontaneous combustion focus on improving battery materials and monitoring overheating. However, these technologies struggle to effectively control heat spread in the event of thermal overload, resulting in the risk of spontaneous combustion remaining unresolved. Summary of the Invention

[0003] In response to the above technical problems, the embodiments of the present application provide a battery pack, a vehicle, and a battery spontaneous combustion protection method equipped with a spontaneous combustion protection device, which can curb the thermal diffusion of the battery from inside the battery and reduce the risk of battery spontaneous combustion.

[0004] The technical solution of this application is achieved as follows:

[0005] In a first aspect, an embodiment of the present application provides a battery pack provided with a spontaneous combustion protection device, comprising:

[0006] Reaction liquid release component; the reaction liquid release component is arranged inside the battery pack;

[0007] When the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid release component is used to release the flame retardant reaction liquid; the characteristics of the flame retardant reaction liquid are: a chemical reaction occurs at the critical temperature of auto-ignition to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack.

[0008] In some embodiments, the battery pack further includes a reaction liquid medium storage component; the reaction liquid medium storage component is disposed inside the battery pack;

[0009] When the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid medium storage assembly is used to release the catalyst; the characteristics of the catalyst are: it works together with the flame retardant reaction liquid at the critical temperature of auto-ignition to generate a target porous substance, and the target porous substance is used to absorb the battery electrolyte inside the battery pack.

[0010] In some embodiments, the reaction liquid release assembly includes at least two reaction liquid release pipelines, and each of the reaction liquid release pipelines is respectively disposed in a different area inside the battery pack.

[0011] In some embodiments, the battery pack further includes a reaction liquid delivery pipeline, and each of the reaction liquid release pipelines is connected to the reaction liquid delivery pipeline;

[0012] The reaction liquid delivery pipeline is used to deliver the flame retardant reaction liquid input from the outside of the battery pack to each of the reaction liquid release pipelines.

[0013] In some embodiments, the reaction liquid delivery pipeline includes at least two reaction liquid delivery segmented pipelines, and each of the reaction liquid delivery segmented pipelines is connected in sequence;

[0014] Each of the reaction liquid delivery segmented pipelines is provided with a pipeline connection port, and one of the pipeline connection ports is correspondingly connected to one of the reaction liquid release pipelines;

[0015] Each of the reaction liquid delivery segmented pipelines is used to deliver the flame retardant reaction liquid to each of the reaction liquid release pipelines at the same reaction liquid delivery pressure.

[0016] In some embodiments, the diameters of the pipeline connection ports provided on each of the reaction liquid delivery segmented pipelines are the same, and the diameters of the at least two reaction liquid delivery segmented pipelines connected in sequence decrease successively from the delivery starting end to the delivery end, so that each of the reaction liquid delivery segmented pipelines can deliver the flame retardant reaction liquid to each of the reaction liquid release pipelines at the same reaction liquid delivery pressure.

[0017] In some embodiments, the reaction liquid medium storage assembly includes at least two reaction liquid medium storage containers; one reaction liquid medium storage container is disposed adjacent to one reaction liquid release pipeline.

[0018] In some embodiments, the reaction liquid medium storage container and the reaction liquid release pipeline are made of the same material.

[0019] In some embodiments, the melting temperature of the reaction liquid delivery pipeline is greater than the autoignition critical temperature.

[0020] In a second aspect, an embodiment of the present application provides a vehicle, comprising a battery pack provided with a spontaneous combustion protection device as described in the first aspect.

[0021] In a third aspect, an embodiment of the present application provides a battery spontaneous combustion protection method, which is applied to the battery pack provided with the spontaneous combustion protection device in the first aspect. The method includes:

[0022] The reaction liquid pump is controlled to deliver the flame retardant reaction liquid that meets the activity requirements to the reaction liquid release component inside the battery pack, so that when the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid release component can release the flame retardant reaction liquid, so that the flame retardant reaction liquid undergoes a chemical reaction inside the battery pack to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack.

[0023] The embodiments of the present application provide a battery pack, a vehicle, and a battery spontaneous combustion protection method equipped with a spontaneous combustion protection device. A reaction liquid release component is provided inside the battery pack, and when the internal temperature of the battery pack reaches the critical temperature of spontaneous combustion, the reaction liquid release component releases a flame-retardant reaction liquid. The flame-retardant reaction liquid undergoes a chemical reaction at the critical temperature of spontaneous combustion to generate a target protective substance that can isolate the air and adheres to the target area of ​​the battery pack, thereby effectively curbing the thermal diffusion of the battery from the inside, reducing the risk of battery spontaneous combustion, and realizing active protection against battery spontaneous combustion. Compared with the traditional method of relying solely on the improvement of the battery body material and battery overheating monitoring, it provides more timely and effective safety protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0025] Figure 1 This is one of the structural schematic diagrams of a battery pack provided with a spontaneous combustion protection device according to an embodiment of the present application;

[0026] Figure 2 This is a second structural diagram of a battery pack provided with a spontaneous combustion protection device according to an embodiment of the present application;

[0027] Figure 3 A schematic structural diagram of a reaction liquid delivery pipeline provided in an embodiment of the present application;

[0028] Figure 4 A cross-sectional view of the structure of a reaction liquid delivery pipeline provided in an embodiment of the present application;

[0029] Figure 5 A schematic structural diagram of a battery spontaneous combustion protection device provided in an embodiment of the present application;

[0030] Figure 6 This is a third structural diagram of a battery pack provided with a spontaneous combustion protection device according to an embodiment of the present application;

[0031] Figure 7 A schematic diagram of the structure of a battery spontaneous combustion protection control system provided in an embodiment of the present application.

[0032] Reference numerals:

[0033] 110: Battery pack; 120: Reaction liquid release assembly; 130: Reaction liquid medium storage assembly; 140: Reaction liquid delivery pipeline; 141: Reaction liquid delivery segmented pipeline; 142: Pipeline connection port; 1: Battery pack; 2: Flame-retardant reaction liquid; 3: Reaction liquid delivery outer tube; 4: Reaction liquid delivery pipeline interface; 5: Reaction liquid medium storage pipeline; 6: Reaction liquid release pipeline; 7: Reaction liquid delivery inner tube; 8: Reaction liquid return pipeline interface; 9: Reaction liquid storage tank; 10: Battery pack shell; 11: Battery cell. DETAILED DESCRIPTION

[0034] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0035] It should be noted that in the description of the embodiments of the present application, the terms "first," "second," etc. are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than that illustrated or described herein. The objects distinguished by "first," "second," etc. are generally of the same type, and do not limit the number of objects. For example, the first object can be one or more.

[0036] The following is an illustrative introduction to the battery pack, vehicle, and battery spontaneous combustion protection method provided with a spontaneous combustion protection device in the embodiments of the present application, in conjunction with the drawings in the embodiments of the present application.

[0037] Figure 1 This is one of the structural diagrams of a battery pack provided with a self-ignition protection device according to an embodiment of the present application, as shown in FIG. Figure 1 As shown, the battery pack 110 includes:

[0038] Reaction liquid release assembly 120; the reaction liquid release assembly 120 is disposed inside the battery pack 110;

[0039] When the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the reaction liquid release component 120 is used to release the flame retardant reaction liquid; the characteristics of the flame retardant reaction liquid are: a chemical reaction occurs at the critical temperature of auto-ignition to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack 110.

[0040] It should be noted that battery pack 110 refers to the integrated structure of a battery module or single battery cell, including core components such as positive and negative electrode materials, electrolyte, and battery cells, and is typically encapsulated in a metal casing. Battery pack 110 is not limited to power batteries for electric vehicles but can also include other batteries with thermal runaway risks, such as industrial equipment batteries, household energy storage batteries, and medical device batteries.

[0041] It should be noted that the reaction liquid release component 120 can be an independent container, such as a capsule, a pipeline, etc., which is embedded inside the battery pack 110 and is used to release the flame retardant reaction liquid when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition.

[0042] In some embodiments, the reaction liquid releasing assembly 120 may be distributed in the gaps between cells or modules inside the battery pack 110 to ensure that the flame retardant reaction liquid can cover the thermal runaway area of ​​the battery pack 110 after being released.

[0043] In some embodiments, the reaction liquid releasing assembly 120 can melt rapidly when the internal temperature of the battery pack 110 reaches the critical temperature of autoignition (eg, 130° C.) to release the flame-retardant reaction liquid therein.

[0044] It should be noted that the shell material of the reaction liquid release component 120 can be selected based on actual applications. The embodiment of the present application does not make any specific restrictions on this. It is only necessary to ensure that the reaction liquid release component 120 can quickly melt to release the flame-retardant reaction liquid when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition.

[0045] It should be noted that the critical temperature of the battery pack 110 may be understood as the initial temperature at which the battery pack 110 spontaneously ignites. For example, the critical temperature may be 130°C, 140°C, 150°C, or 160°C.

[0046] In some embodiments, the shell of the reaction liquid release assembly 120 can be made of polyvinylidene fluoride (PVDF), and its melting point is adjusted to the critical temperature of the autoignition of the battery pack 110. PVDF is a semi-crystalline fluoropolymer with corrosion resistance and is suitable for the complex chemical environment within the battery pack 110.

[0047] It should be noted that the flame retardant reaction liquid in the embodiment of the present application is a liquid that can undergo a chemical reaction at the critical temperature of auto-ignition of the battery pack 110. It does not react with the material of the battery pack 110 at room temperature, but quickly generates a target protective substance that can isolate the air at the critical temperature of auto-ignition of the battery pack 110 and adheres to the target area of ​​the battery pack 110.

[0048] In some embodiments, the target protective substance generated by the chemical reaction of the flame retardant reaction liquid at the critical temperature of autoignition can be a solid substance, such as glass powder, ceramic layer, etc.

[0049] It should be noted that the target protective material has an insulating property, which can prevent oxygen from contacting the materials of the battery pack 110 , and is also high temperature resistant and is not easily decomposed under continuous high temperatures.

[0050] For example, the power battery cell of an electric vehicle rises to 130°C (the critical temperature of auto-ignition of the power battery) due to an internal short circuit. At this time, the reaction liquid release component inside the power battery melts, releasing a flame retardant reaction liquid. The flame retardant reaction liquid contacts the surface of the high-temperature battery cell to form a silicon dioxide SiO2 ceramic layer covering the thermal runaway battery cell. The SiO2 ceramic layer isolates oxygen and blocks heat transfer to adjacent battery cells, preventing heat diffusion.

[0051] It should be noted that the target area of ​​the battery pack 110 in the embodiment of the present application refers to the thermal runaway area within the battery pack 110. For example, if a battery cell within the battery pack 110 experiences thermal runaway, the target protective material will adhere to the surface of the battery cell to prevent its heat from being transferred to other batteries or areas within the battery pack 110.

[0052] In some embodiments, the flame retardant reaction liquid can be pre-delivered or stored in the reaction liquid release assembly 120 so that when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the reaction liquid release assembly 120 can immediately release the flame retardant reaction liquid.

[0053] In some embodiments, when it is determined that the internal temperature of the battery pack 110 is about to reach the critical temperature of auto-ignition, the flame retardant reaction liquid can be transported into the reaction liquid release component 120 to ensure that when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the flame retardant reaction liquid released by the reaction liquid release component 120 has a higher activity.

[0054] It can be understood that the battery pack provided with a spontaneous combustion protection device provided in the embodiment of the present application, by arranging a reaction liquid release component inside the battery pack, and allowing the reaction liquid release component to release a flame-retardant reaction liquid when the internal temperature of the battery pack reaches the critical temperature of spontaneous combustion. The flame-retardant reaction liquid will undergo a chemical reaction at the critical temperature of spontaneous combustion to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack, thereby effectively curbing the heat diffusion of the battery from the inside, reducing the risk of battery spontaneous combustion, and realizing active protection against battery spontaneous combustion. Compared with the traditional method of relying solely on the improvement of the battery body material and battery overheating monitoring, it provides more timely and effective safety protection.

[0055] In some embodiments, as Figure 2 As shown, the battery pack 110 further includes a reaction liquid medium storage assembly 130 ; the reaction liquid medium storage assembly 130 is disposed inside the battery pack 110 ;

[0056] When the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the reaction liquid medium storage assembly 130 is used to release the catalyst; the characteristics of the catalyst are: it acts together with the flame retardant reaction liquid at the critical temperature of auto-ignition to generate a target porous substance, and the target porous substance is used to absorb the battery electrolyte inside the battery pack 110.

[0057] It should be noted that the reaction liquid medium storage assembly 130 is similar to the reaction liquid release assembly 120 and is both disposed inside the battery pack 110 , but the reaction liquid medium storage assembly 130 is specifically used to store catalysts.

[0058] It should be noted that the catalyst stored in the reaction liquid medium storage assembly 130 is stable at room temperature and does not react with the materials of the battery pack 110. However, at the critical temperature of autoignition of the battery pack 110, the catalyst can activate the rapid chemical conversion of the flame-retardant reaction liquid to generate a target porous substance to absorb the battery electrolyte inside the battery pack 110.

[0059] It should be noted that the target porous material structure is a porous structure with high specific surface area and porosity, which can quickly absorb battery electrolyte.

[0060] For example, an electric vehicle's power battery cell experiences an internal short circuit, causing its temperature to rise to 130°C (the critical temperature for autoignition). This causes the reaction liquid release assembly inside the battery to melt, releasing a flame-retardant reaction liquid. Simultaneously, the reaction liquid medium storage assembly also melts, releasing a catalyst. The flame-retardant reaction liquid contacts the surface of the high-temperature cell, forming a silicon dioxide (SiO2) ceramic layer that covers the thermal runaway cell. This layer isolates oxygen and blocks heat transfer to adjacent cells, preventing heat diffusion. Furthermore, the flame-retardant reaction liquid reacts with the catalyst to form a porous silica gel that absorbs the battery electrolyte, preventing leakage.

[0061] It can be understood that the embodiments of the present application, through the synergistic effect of the flame-retardant reaction liquid and the catalyst, achieve the purpose of preventing heat diffusion and electrolyte leakage from inside the battery pack when the battery pack spontaneously combusts, thereby essentially blocking the battery pack thermal runaway chain reaction, dispersing the fire material, and preventing the occurrence of secondary oxidation corrosion caused by leakage of the battery electrolyte.

[0062] In some embodiments, the reaction liquid release assembly 120 includes at least two reaction liquid release pipelines, and each of the reaction liquid release pipelines is respectively disposed in a different area inside the battery pack 110 .

[0063] It can be understood that by arranging multiple reaction liquid release pipelines in different areas inside the battery pack 110, it can be ensured that when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the released flame-retardant reaction liquid can cover all thermal runaway areas inside the battery pack 110.

[0064] In some embodiments, the at least two reaction liquid release pipelines included in the reaction liquid release assembly 120 can be multiple independent pipelines or multiple branch pipelines led out from a reaction liquid release main pipeline to pass through the key thermal runaway area inside the battery pack 110.

[0065] In some embodiments, each reaction liquid release pipeline can be provided adjacent to each battery cell inside the battery pack 110 .

[0066] It can be understood that the embodiment of the present application can ensure that when the battery pack 110 spontaneously combusts, the flame-retardant reaction liquid can fully cover all thermal runaway areas inside the battery pack 110 by setting reaction liquid release pipelines in different areas inside the battery pack 110.

[0067] In some embodiments, the battery pack 110 further includes a reaction liquid delivery pipeline, and each of the reaction liquid release pipelines is connected to the reaction liquid delivery pipeline;

[0068] The reaction liquid delivery pipeline is used to deliver the flame retardant reaction liquid input from the outside of the battery pack 110 to each of the reaction liquid release pipelines.

[0069] It should be noted that the reaction liquid delivery pipeline can be arranged inside the battery pack 110 to transport the flame-retardant reaction liquid input from the outside of the battery pack 110 to each reaction liquid release pipeline, and the reaction liquid delivery pipeline needs to be resistant to high temperature and corrosion. When the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the reaction liquid delivery pipeline will not melt.

[0070] In some embodiments, the reaction liquid delivery pipeline may include an inner reaction liquid delivery pipeline and an outer reaction liquid delivery pipeline, wherein the inner reaction liquid delivery pipeline is disposed inside the battery pack 110, and the outer reaction liquid delivery pipeline is disposed outside the battery pack 110, and the inner reaction liquid delivery pipeline and the outer reaction liquid delivery pipeline are connected, and their connection ends are located in the shell of the battery pack 110. The outer reaction liquid delivery pipeline can deliver the flame-retardant reaction liquid to the inner reaction liquid delivery pipeline, and then the inner reaction liquid delivery pipeline can deliver the flame-retardant reaction liquid to each reaction liquid release pipeline.

[0071] It can be understood that the embodiments of the present application can inject fresh, highly active flame-retardant reaction liquid into the battery pack through the reaction liquid delivery pipeline when needed (such as when an abnormal temperature inside the battery pack is detected or when regular maintenance is performed), without the need to pre-store the flame-retardant reaction liquid in the reaction liquid release pipeline to avoid the flame-retardant reaction liquid from losing its activity due to chemical degradation caused by long-term storage.

[0072] In some embodiments, as Figure 3 As shown, the reaction liquid delivery pipeline 140 includes at least two reaction liquid delivery segmented pipelines 141, and each of the reaction liquid delivery segmented pipelines 141 is connected in sequence;

[0073] Each of the reaction liquid delivery segmented pipelines 141 is provided with a pipeline connection port 142 , and one of the pipeline connection ports 142 is correspondingly connected to one of the reaction liquid release pipelines;

[0074] Each of the reaction liquid delivery segmented pipelines 141 is used to deliver the flame retardant reaction liquid to each of the reaction liquid release pipelines at the same reaction liquid delivery pressure.

[0075] It can be understood that in the embodiment of the present application, the main delivery pipeline (i.e., the reaction liquid delivery pipeline 140) is divided into multiple segmented pipelines (i.e., the reaction liquid delivery segmented pipeline 141), and each segment corresponds to a reaction liquid release pipeline, forming a "one-to-one" precise delivery network, and the number of reaction liquid delivery segmented pipelines 141 is the same as the number of reaction liquid release pipelines, which can ensure that each thermal management area has an exclusive supply channel and avoid the problem of uneven pressure drop caused by long-distance delivery of a single pipeline.

[0076] In some embodiments, the pipeline connection port 142 set on each reaction liquid delivery segmented pipeline 141 can be integrated with a pressure balancing valve to ensure that the pressure of each branch is consistent, that is, each reaction liquid delivery segmented pipeline 141 delivers the flame retardant reaction liquid to each reaction liquid release pipeline at the same reaction liquid delivery pressure.

[0077] It can be understood that the embodiment of the present application achieves efficient and balanced distribution of flame-retardant reaction liquid by setting up one-to-one precise docking and equal pressure delivery control of reaction liquid delivery segmented pipelines and reaction liquid release pipelines, ensuring that each area inside the battery pack obtains equal and synchronous flame-retardant protection response.

[0078] In some embodiments, the diameters of the pipeline connection ports 142 provided on each of the reaction liquid delivery segmented pipelines 141 are the same, and the diameters of the at least two reaction liquid delivery segmented pipelines 141 connected in sequence decrease successively from the delivery starting end to the delivery end, so that each of the reaction liquid delivery segmented pipelines 141 can deliver the flame retardant reaction liquid to each of the reaction liquid release pipelines at the same reaction liquid delivery pressure.

[0079] It should be noted that, in order to ensure that each reaction liquid delivery segmented pipeline 141 can deliver the flame retardant reaction liquid to each reaction liquid release pipeline at the same reaction liquid delivery pressure, the diameter of each reaction liquid delivery segmented pipeline 141 can be set to decrease gradually from the delivery start to the delivery end, such as Figure 3 or Figure 4 shown.

[0080] In some embodiments, the diameter of each reaction liquid delivery segmented pipeline 141, the diameter of the pipeline connection port 142, and the number of reaction liquid delivery segmented pipelines 141 can be constrained by first and second conditions. The first and second conditions can be determined based on fluid mechanics principles and engineering constraints.

[0081] For example, Figure 4 A cross-sectional view of a reaction liquid delivery pipeline provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, it includes 5 reaction liquid delivery segmented pipelines, and the diameters of the reaction liquid delivery segmented pipelines are different. From top to bottom, the diameter of the first reaction liquid delivery segmented pipeline is d1, the diameter of the second reaction liquid delivery segmented pipeline is d2, and the diameter of the pipeline connection port set on each reaction liquid delivery segmented pipeline is d a .

[0082] In some embodiments, in order to ensure that each pipeline connection port 142 has sufficient reaction liquid flow, the diameter of any two adjacent reaction liquid delivery segmented pipelines 141 and the diameter of the pipeline connection port 142 can satisfy the first condition shown in formula (1):

[0083]

[0084] Among them, d m and d m+1 represents the diameter of any two adjacent reaction liquid delivery segmented pipelines 141, d a Indicates the diameter of the pipe connection port 142.

[0085] In some embodiments, in order to ensure that each pipeline connection port 142 has sufficient reaction liquid flow, the diameter of the first reaction liquid delivery segmented pipeline 141 at the top of the reaction liquid delivery pipeline 140, the diameter of the pipeline connection port 142, and the number of the reaction liquid delivery segmented pipelines 141 can satisfy the second condition shown in formula (2):

[0086]

[0087] Wherein, d1 represents the diameter of the first reaction liquid delivery segmented pipeline 141 at the top of the reaction liquid delivery pipeline 140, d a represents the diameter of the pipeline connection port 142 , and n represents the number of the reaction liquid delivery segmented pipelines 141 .

[0088] It can be understood that, under the constraints of the first condition and the second condition, the diameter of each reaction liquid delivery segment pipeline 141 decreases gradually from the delivery start end to the delivery end end.

[0089] It can be understood that the embodiment of the present application constrains the diameter of each reaction liquid transport segmented pipeline and sets the diameter of each reaction liquid transport segmented pipeline to gradually decrease from the starting end to the end of the transport. This can ensure that all reaction liquid transport segmented pipelines evenly distribute the flame retardant reaction liquid under the same pressure, eliminate the uneven pressure loss problem caused by differences in pipeline length or branches, and improve the reliability of battery pack thermal runaway suppression.

[0090] In some embodiments, the reaction liquid medium storage assembly 130 includes at least two reaction liquid medium storage containers; one reaction liquid medium storage container is disposed adjacent to one reaction liquid release pipeline.

[0091] It should be noted that in the embodiment of the present application, a reaction liquid medium storage container is arranged adjacent to each reaction liquid release pipeline, which can ensure that each flame retardant reaction liquid release point is supplied with catalyst, thereby ensuring that the flame retardant reaction liquid and the catalyst can be quickly mixed to produce a chemical reaction.

[0092] It should be noted that if the spacing between the reaction liquid medium storage container and the reaction liquid release pipeline is smaller than a set value (eg, 5 mm, 2 mm, etc.), the reaction liquid medium storage container and the reaction liquid release pipeline can be considered to be adjacently arranged.

[0093] In some embodiments, the reaction liquid medium storage container and the reaction liquid release pipeline are made of the same material.

[0094] It should be noted that in the embodiment of the present application, the reaction liquid medium storage container and the reaction liquid release pipeline can be made of exactly the same material (such as PVDF), that is, the reaction liquid medium storage container and the reaction liquid release pipeline are made of the same material, so that when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the reaction liquid medium storage container and the reaction liquid release pipeline can melt at the same time to release the flame-retardant reaction liquid and catalyst at the same time.

[0095] In some embodiments, the melting temperature of the reaction liquid delivery pipeline 140 is greater than the autoignition critical temperature.

[0096] It should be noted that in the embodiment of the present application, the melting temperature of the reaction liquid delivery pipeline 140 is set to be greater than the critical temperature of auto-ignition of the battery pack 110, which can ensure that when the internal temperature of the battery pack 110 reaches the critical temperature of auto-ignition, the reaction liquid release component 120 and the reaction liquid medium storage component 130 melt, while the reaction liquid delivery pipeline 140 does not melt, so as to avoid the flame-retardant reaction liquid from being damaged by high temperature in its delivery channel before the coverage is completed.

[0097] In some embodiments, the flame retardant reaction liquid is ethyl orthosilicate, and the catalyst is ammonium bicarbonate.

[0098] It should be noted that tetraethyl orthosilicate (TEOS, Si(OC2H5)4) is a colorless liquid that decomposes in water or acid and can condense to form SiO2 at high temperatures. Furthermore, under the action of a catalyst, tetraethyl orthosilicate can quickly form a ceramic barrier that isolates oxygen and heat.

[0099] It should be noted that ammonium bicarbonate (NH4HCO3) is a white crystal that can decompose into NH3, CO2, and H2O at high temperatures (around 58°C). Moreover, the NH3 produced by the decomposition of ammonium bicarbonate can accelerate the hydrolysis of TEOS, CO2 dilutes oxygen, and H2O participates in the polycondensation reaction.

[0100] It can be understood that the embodiment of the present application sets the flame retardant reaction liquid to ethyl orthosilicate and the catalyst to ammonium bicarbonate, so that when the internal temperature of the battery pack reaches the critical temperature of autoignition, the ethyl orthosilicate undergoes a chemical reaction at the critical temperature of autoignition to generate a target protective substance (i.e., a silica ceramic layer) that can isolate the air and adhere to the target area of ​​the battery pack, thereby effectively curbing the thermal diffusion of the battery from the inside and reducing the risk of battery spontaneous combustion. In addition, ethyl orthosilicate and ammonium bicarbonate work together at the critical temperature of autoignition to generate a target porous substance (i.e., porous SiO2 aerogel) to absorb the battery electrolyte, so as to prevent the occurrence of secondary oxidation corrosion caused by leakage of the battery electrolyte.

[0101] In some embodiments, the flame retardant reaction liquid is a melamine derivative, and the catalyst is ammonium polyphosphate.

[0102] It should be noted that melamine derivatives (such as melamine cyanurate) decompose at high temperatures to produce non-combustible gases such as NH3 and N2, which dilute oxygen and inhibit the combustion chain reaction. Furthermore, at high temperatures, ammonium polyphosphate and melamine derivatives work together to form a porous flame-retardant layer (i.e., a porous structured material) through the following steps:

[0103] (1) Decomposition: Ammonium polyphosphate generates polyphosphoric acid and NH3; melamine derivatives (such as melamine cyanurate) release melamine, cyanuric acid, and NH3 / N2.

[0104] (2) Carbonization: Polyphosphoric acid condenses with cyanuric acid to form a cross-linked carbon layer.

[0105] (3) Foaming: NH3 / N2 forms bubbles in the viscous carbon layer, and a porous structure material is obtained after solidification.

[0106] It should be noted that the flame retardant reaction liquid and the corresponding catalyst with flame retardant properties can be adaptively selected based on actual applications. The embodiments of the present application do not impose specific restrictions on this. It is only necessary to ensure that the flame retardant reaction liquid has the characteristic of undergoing a chemical reaction at the critical temperature of auto-ignition of the battery pack to generate a protective substance that can isolate the air and adhere to the thermal runaway area of ​​the battery pack, and the catalyst has the characteristic of working together with the flame retardant reaction liquid at the critical temperature of auto-ignition of the battery pack to generate a porous substance to absorb the battery electrolyte.

[0107] For example, Figure 5 A schematic diagram of the structure of a battery spontaneous combustion protection device provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, the device includes a battery pack 1, a flame retardant reaction liquid 2, a reaction liquid delivery outer tube 3, a reaction liquid delivery pipeline interface 4, a reaction liquid medium storage pipeline 5, a reaction liquid release pipeline 6, a reaction liquid delivery inner tube 7, a reaction liquid return pipeline interface 8 and a reaction liquid storage tank 9.

[0108] It should be noted that the flame retardant reaction liquid 2 can produce a chemical reaction at the critical temperature of the autoignition of the battery pack 1 (e.g., 130°C), generating a fire-resistant, high-temperature-resistant, and corrosion-resistant fireproof material (i.e., the target protective material) that is dispersed and adsorbed on the internal surface of the battery pack 1. The flame retardant reaction liquid 2 used in the embodiment of the present application is ethyl orthosilicate, which hydrolyzes and condenses under heating conditions to form a silicon dioxide network, thereby preventing the battery pack 1 from spontaneous combustion.

[0109] In some embodiments, the outer reaction liquid transport tube 3 may be made of a soft material tube, and has corrosion resistance and high temperature resistance properties.

[0110] In some embodiments, the reaction liquid delivery pipeline interface 4 and the reaction liquid return pipeline interface 8 can be fixed on the shell of the battery pack 1 to connect the reaction liquid delivery outer tube 3 to form a closed loop.

[0111] It should be noted that the reaction liquid medium storage pipeline 5 stores a catalyst. To match the flame retardant reaction liquid 2 with ethyl orthosilicate, this embodiment of the application uses ammonium bicarbonate as a catalyst, and its reaction temperature is adjusted to the critical temperature of the autoignition of the battery pack 1 (e.g., 130°C).

[0112] In some embodiments, the outer tube material of the reaction liquid medium storage line 5 is the same as that of the reaction liquid release line 6, and this material can melt at the critical temperature of the autoignition of the battery pack 1 (e.g., 130°C), allowing the outer tube material of the reaction liquid medium storage line 5 and the reaction liquid release line 6 to release the catalyst and flame-retardant reaction liquid, respectively. The flame-retardant reaction liquid undergoes a chemical reaction at the critical temperature to produce a fire-retardant substance to achieve a flame-retardant effect. At the same time, the flame-retardant reaction liquid and the catalyst work together to form a porous material that can better absorb the battery electrolyte.

[0113] In some embodiments, the material of the reaction liquid release line 6 can be polyvinylidene fluoride (PVDF), and its melting point can be lowered to the critical temperature of autoignition of the battery pack 1 (eg, 130° C.) by modification or copolymerization.

[0114] It should be noted that the reaction liquid release pipe 6 has the characteristics of being corrosion-resistant and resistant to temperatures below the critical temperature of autoignition of the battery pack 1 (eg, 130° C.) and fire.

[0115] It should be noted that the reaction liquid conveying inner tube 7 has the characteristics of high temperature resistance, fire resistance and oxidation corrosion resistance, and can ensure that the liquid pressure of each branch thereof is consistent.

[0116] It should be noted that the reaction liquid storage tank 9 provides circulation power for the flame-retardant reaction liquid 2 and has the functions of detecting the activity of the reaction liquid and providing an alarm for the deactivation of the reaction liquid, thereby reminding the user to promptly replace the flame-retardant reaction liquid 2 inside the reaction liquid storage tank 9. Since the flame-retardant reaction liquid is a non-common substance, its activity needs to be tested, and if it is found to be deactivated, it needs to be replaced.

[0117] It should be noted that the battery spontaneous combustion protection device provided in the embodiment of the present application has the following working principle: the flame retardant reaction liquid is transported to the interior of the battery pack through a delivery pipeline under a certain pressure. When the internal temperature of the battery pack reaches the critical temperature of spontaneous combustion or reaches the initial temperature of spontaneous combustion, the corresponding section of the reaction liquid release pipeline melts at high temperature to release the flame retardant reaction liquid. The flame retardant reaction liquid reacts at the corresponding temperature to generate a new fire-resistant and high-temperature resistant target protective substance that adheres to the internal surface of the battery pack to achieve the effect of isolating the air and flame retardant. During the reaction of the flame retardant reaction liquid, under the catalytic state of the corresponding catalyst, the target porous substance is generated to achieve the purpose of absorbing the battery electrolyte. At the same time, the flame retardant reaction liquid can be maintained at a certain pressure in the reaction liquid release pipeline by a pressure retainer. Once the reaction liquid release pipeline melts, there will be enough pressure to supply the flame retardant reaction liquid to the required position inside the battery pack.

[0118] For example, Figure 6 The third structural diagram of a battery pack provided with a self-ignition protection device according to an embodiment of the present application is as follows: Figure 6 As shown, the battery pack includes: a flame retardant reaction liquid 2, a reaction liquid delivery outer tube 3, a reaction liquid delivery pipeline interface 4, a reaction liquid medium storage pipeline 5, a reaction liquid release pipeline 6, a reaction liquid delivery inner tube 7, a reaction liquid return pipeline interface 8, a reaction liquid storage tank 9, a battery pack shell 10 and a battery cell 11. It should be noted that when the battery cell 11 inside the battery pack undergoes thermal runaway, the reaction liquid medium storage pipeline 5 and the reaction liquid release pipeline 6 can melt at the same time, releasing the catalyst and the flame retardant reaction liquid respectively. The flame retardant reaction liquid undergoes a chemical reaction to generate a fireproof substance to achieve a flame retardant effect. At the same time, the flame retardant reaction liquid and the catalyst work together to generate a porous substance to absorb the battery electrolyte.

[0119] It is understandable that the battery pack provided with a self-ignition protection device provided in the embodiment of the present application can bring at least the following beneficial effects: (1) Rapid flame retardant protection: When the temperature inside the battery pack reaches the critical point of self-ignition, a chemical reaction is quickly triggered to generate a high-temperature resistant protective layer (such as SiO2 ceramic) covering the internal surface of the battery pack to isolate oxygen and effectively prevent the spread of combustion. (2) Electrolyte absorption and leakage prevention: The reaction generates a substance with a porous structure (such as porous SiO2 aerogel), which can efficiently adsorb leaked battery electrolyte, prevent its diffusion from causing secondary combustion or corrosion, and improve overall safety. (3) Adaptive intelligent protection: It relies entirely on temperature triggering, does not require external intervention, reduces dependence on temperature control measurement, etc., and can automatically form dual protection of physical isolation and chemical adsorption in the early stage of thermal runaway of the battery pack, greatly reducing the risk of self-ignition.

[0120] It should be noted that, based on the battery pack provided with the self-ignition protection device in the embodiments of this application, the technical effects of this application can be achieved by selecting flame-retardant reaction liquids, reaction liquid media, pipeline materials, and component models with similar performance conditions. Those skilled in the art can make various modifications or variations without inventive effort and still fall within the scope of protection of this application.

[0121] For example, Figure 7 A schematic diagram of a battery spontaneous combustion protection control system provided in an embodiment of the present application is shown in FIG. Figure 7 As shown, the system includes a main control chip 710, a core computing chip 720, a first power supply unit 730, a second power supply unit 740, an actuator control unit 750, an analog / digital acquisition chip 760, a RAM and ROM 770, and an output and alarm circuit 780. The core computing chip 720 can calculate the flame retardant reaction liquid activity signal (the concentration of the active component of the flame retardant reaction liquid) collected by the analog / digital acquisition chip 760 and the reaction liquid deactivation model level threshold (pre-set reaction liquid deactivation threshold) stored in the RAM and ROM 770, and transmit the calculation result to the main control chip 710. The main control chip 710 calculates the flame retardant reaction liquid deactivation risk level and transmits the flame retardant reaction liquid deactivation risk level to the output and alarm circuit 780 to display an indication of whether the flame retardant reaction liquid needs to be replaced. The actuator control unit 750, based on instructions from the main control chip 710, controls the second power supply unit 740 to control the operation of the reaction liquid pump, circulate the flame retardant reaction liquid at a certain pressure, and ensure that the flame retardant reaction liquid has the same pressure and activity throughout the system. The first power supply unit 730 is used to provide power support to the core computing chip 720.

[0122] The present application also provides a method for preventing battery spontaneous combustion, which is applied to a battery pack provided with a spontaneous combustion protection device provided in any of the above embodiments. The method includes:

[0123] The reaction liquid pump is controlled to deliver the flame retardant reaction liquid that meets the activity requirements to the reaction liquid release component inside the battery pack, so that when the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid release component can release the flame retardant reaction liquid, so that the flame retardant reaction liquid undergoes a chemical reaction inside the battery pack to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack.

[0124] It should be noted that the flame retardant reaction liquid that meets the activity requirements can be a flame retardant reaction liquid whose concentration reaches a set threshold value, so as to ensure that the flame retardant reaction liquid has high activity and can quickly undergo chemical reactions at the critical temperature of auto-ignition of the battery pack to generate target protective substances that can isolate the air.

[0125] It should be noted that the reaction liquid pump is the core executive component for delivering flame-retardant reaction liquid. When the risk of thermal runaway of the battery pack is detected, the flame-retardant reaction liquid can be quickly and accurately delivered to the reaction liquid release component inside the battery pack, so that the reaction liquid release component can release the flame-retardant reaction liquid. The flame-retardant reaction liquid undergoes a chemical reaction inside the battery pack to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack (such as the thermal runaway area) to achieve a flame retardant effect.

[0126] It is understandable that the embodiments of the present application can be applied to the protection scenario of thermal runaway of power batteries in electric vehicles. The protection principle is that when the power battery has undergone thermal diffusion due to an accident (such as a collision, overcharging, etc.), it can automatically trigger a chemical reaction after reaching the critical temperature of the power battery's spontaneous combustion, generating a high-temperature resistant isolation layer to block combustion, and at the same time forming a porous adsorption material to absorb the battery electrolyte, thereby effectively suppressing heat spread and preventing secondary corrosion caused by battery electrolyte leakage. Compared with the limitation of traditional active temperature control solutions that cannot cope with the sudden damage caused by thermal runaway of power batteries, the solution of the embodiments of the present application can still significantly reduce losses after thermal runaway of power batteries occurs, significantly improve the safety of electric vehicles, and protect user property to a greater extent.

[0127] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0128] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the embodiments of the present application may take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware. Furthermore, the embodiments of the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) containing computer-usable program code.

[0129] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0130] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0131] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0132] The above description is merely an optional embodiment of the present application and is not intended to limit the scope of protection of the present application.

Claims

1. A battery pack provided with a self-ignition protection device, characterized in that: include: Reaction liquid release component; the reaction liquid release component is arranged inside the battery pack; When the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid release component is used to release the flame-retardant reaction liquid; the characteristics of the flame-retardant reaction liquid are: a chemical reaction occurs at the critical temperature of auto-ignition to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack.

2. The battery pack provided with a self-ignition protection device according to claim 1, characterized in that: The battery pack further includes a reaction liquid medium storage component; the reaction liquid medium storage component is disposed inside the battery pack; When the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid medium storage assembly is used to release the catalyst; the characteristics of the catalyst are: it works together with the flame retardant reaction liquid at the critical temperature of auto-ignition to generate a target porous substance, and the target porous substance is used to absorb the battery electrolyte inside the battery pack.

3. The battery pack provided with a self-ignition protection device according to claim 2, characterized in that: The reaction liquid release assembly includes at least two reaction liquid release pipelines, and each of the reaction liquid release pipelines is respectively arranged in a different area inside the battery pack.

4. The battery pack provided with a self-ignition protection device according to claim 3, characterized in that: The battery pack further includes a reaction liquid delivery pipeline, and each of the reaction liquid release pipelines is connected to the reaction liquid delivery pipeline; The reaction liquid delivery pipeline is used to deliver the flame retardant reaction liquid input from the outside of the battery pack to each of the reaction liquid release pipelines.

5. The battery pack provided with a self-ignition protection device according to claim 4, characterized in that: The reaction liquid delivery pipeline includes at least two reaction liquid delivery segmented pipelines, and each of the reaction liquid delivery segmented pipelines is connected in sequence; Each of the reaction liquid delivery segmented pipelines is provided with a pipeline connection port, and one of the pipeline connection ports is correspondingly connected to one of the reaction liquid release pipelines; Each of the reaction liquid delivery segmented pipelines is used to deliver the flame retardant reaction liquid to each of the reaction liquid release pipelines at the same reaction liquid delivery pressure.

6. The battery pack provided with a self-ignition protection device according to claim 5, characterized in that: The diameters of the pipeline connection ports provided on each of the reaction liquid delivery segmented pipelines are the same, and the diameters of the at least two reaction liquid delivery segmented pipelines connected in sequence decrease successively from the delivery starting end to the delivery end, so that each of the reaction liquid delivery segmented pipelines can deliver the flame retardant reaction liquid to each of the reaction liquid release pipelines at the same reaction liquid delivery pressure.

7. The battery pack provided with a self-ignition protection device according to claim 5, characterized in that: The reaction liquid medium storage assembly includes at least two reaction liquid medium storage containers; one reaction liquid medium storage container is disposed adjacent to one reaction liquid release pipeline.

8. The battery pack provided with a self-ignition protection device according to claim 7, characterized in that: The reaction liquid medium storage container and the reaction liquid release pipeline are made of the same material.

9. The battery pack provided with a self-ignition protection device according to any one of claims 4 to 8, characterized in that: The melting temperature of the reaction liquid delivery pipeline is greater than the autoignition critical temperature.

10. A vehicle, characterized in that: The vehicle includes the battery pack provided with a self-ignition protection device according to any one of claims 1 to 9.

11. A method for protecting a battery from spontaneous combustion, characterized in that: Applied to the battery pack provided with a self-ignition protection device according to any one of claims 1 to 9, the method comprising: The reaction liquid pump is controlled to deliver the flame retardant reaction liquid that meets the activity requirements to the reaction liquid release component inside the battery pack, so that when the internal temperature of the battery pack reaches the critical temperature of auto-ignition, the reaction liquid release component can release the flame retardant reaction liquid, so that the flame retardant reaction liquid undergoes a chemical reaction inside the battery pack to generate a target protective substance that can isolate the air and adhere to the target area of ​​the battery pack.

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