Thermal runaway suppression method and system for energy storage battery

Abstract

The invention discloses a thermal runaway suppression method and system for an energy storage battery, and the method comprises the steps: collecting the temperature of the energy storage battery in real time, comparing the temperature with a plurality of preset temperature thresholds, triggering first-stage treatment according to an obtained temperature comparison result when a first-stage treatment condition is reached, and delaying the rise of the internal temperature of the battery through the first-stage treatment by applying current discharge; when a second-stage treatment condition is met, triggering second-stage treatment, and increasing the current discharge multiplying power to a corresponding multiplying power calculated according to the thermal runaway condition of the current energy storage battery by the second-stage treatment; when the third-level disposal condition is met, third-level disposal is triggered, and the discharge current of the third-level disposal controls the corresponding discharge rate according to the real-time remaining electric quantity of the batteries, the gradient change of temperature distribution in the module and the number of the fault batteries; thermal runaway suppression of the energy storage battery is realized through first-stage treatment, second-stage treatment and third-stage treatment. The maximum temperature and harm of battery thermal runaway can be reduced, module-level expansion of battery thermal runaway is avoided, and thermal runaway development is inhibited from the source.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energy storage battery safety prevention and control, and particularly relates to an energy storage battery thermal runaway suppression method and system. BACKGROUND

[0002] Lithium-ion batteries have been widely used in electric vehicles and energy storage systems due to their high energy density and long cycle life, and have become the key energy storage components driving the development of these fields.

[0003] However, lithium-ion batteries face serious threats in safety applications, with the problem of thermal runaway (TR) being particularly prominent. Under abuse conditions such as high temperature, overcharge, and internal short circuit, a series of chain heat release reactions occur inside the lithium-ion battery. These reactions can cause the battery temperature to rise sharply, and when the temperature exceeds a certain threshold, it can trigger serious safety accidents such as fire and explosion, causing great damage to personnel life and property safety.

[0004] To solve the problem of lithium-ion battery thermal runaway, researchers have proposed various thermal runaway suppression strategies, including: (1) Use of solid-state electrolyte: Solid-state electrolyte can improve the safety of the battery to some extent, but due to its complex preparation process and the need to improve the performance of the solid-state electrolyte, such as ion conductivity, the overall cost of the battery using this technology is high, limiting its large-scale application.

[0005] (2) Add flame retardant: Adding flame retardant to battery materials can suppress the combustion reaction of the battery during thermal runaway, but the addition of flame retardant may affect the electrochemical performance of the battery, such as reducing the energy density and cycle life of the battery, and the selection and addition amount of flame retardant need to be accurately controlled, otherwise it is difficult to achieve the ideal suppression effect.

[0006] (3) Design thermal management system: By designing a reasonable thermal management system, the temperature of the battery can be monitored and adjusted during the operation of the battery to prevent the battery temperature from being too high. However, the thermal management system requires additional equipment and technical support, which increases the complexity and cost of the battery system, and in extreme abuse conditions, the thermal management system may not be able to completely prevent the occurrence of thermal runaway.

[0007] Therefore, the existing thermal runaway suppression methods often have problems such as high cost, complex process, or limited effect, making it difficult to comprehensively and effectively solve the problem of lithium-ion battery thermal runaway, and there is an urgent need for a more effective thermal runaway suppression technology. SUMMARY

[0008] The purpose of the present application is to provide a method and system for inhibiting thermal runaway of energy storage batteries to reduce the maximum temperature and harm of battery thermal runaway, avoid the expansion of battery thermal runaway at the module level, inhibit the development of thermal runaway from the source, and improve the active safety protection capability of the energy storage system to avoid the hysteresis of traditional end protection measures.

[0009] To achieve the above-mentioned purpose, the present application has the following technical solutions: In a first aspect, a method for inhibiting thermal runaway of energy storage batteries is provided, comprising: Real-time acquisition of the temperature of the energy storage battery and comparison with a plurality of pre-set temperature thresholds to obtain a temperature comparison result; According to the obtained temperature comparison result, when a first level of disposal condition is reached, a first level of disposal is triggered, which delays the rise of the internal temperature of the battery by applying a current discharge; when a second level of disposal condition is reached, a second level of disposal is triggered, which increases the discharge rate of the current to a corresponding rate calculated according to the current thermal runaway condition of the energy storage battery; when a third level of disposal condition is reached, a third level of disposal is triggered, and the discharge current of the third level of disposal controls the corresponding discharge rate according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module, and the number of faulty batteries; the levels of the first, second, and third levels of disposal are sequentially increased, and the inhibition of thermal runaway of the energy storage battery is realized through the first, second, and third levels of disposal.

[0010] As a preferred solution, the first level of disposal condition is that the temperature of the energy storage battery reaches a first temperature threshold or the energy storage system sends a first level of alarm signal; The second level of disposal condition is that the temperature of the energy storage battery reaches a second temperature threshold or a battery safety valve opening signal is detected or the energy storage system sends a second level of alarm; The third level of disposal condition is that the temperature rise rate of one or more energy storage batteries in the energy storage battery module is greater than 1℃ / s or the energy storage system has a third level of alarm.

[0011] As a preferred solution, the value a of the first temperature threshold ranges from 50℃ to 120℃, and the discharge rate of the first level of disposal when applying current discharge is 0.01C to 0.5C.

[0012] As a preferred solution, the value b of the second temperature threshold ranges from the value a of the first temperature threshold to 250℃, and the discharge rate of the current according to the current thermal runaway condition of the energy storage battery is calculated according to the following expression: h In the formula, d is the discharge rate of the second level of disposal; T is the current average temperature of the energy storage battery module; T safe is the upper limit of the safe working temperature of the energy storage battery; and T alertis a secondary alarm trigger temperature threshold; N abn is the number of energy storage batteries with temperature anomalies, equal to the number of single batteries whose temperature exceeds T alert ; N total is the total number of batteries of the energy storage battery module; e is a basic discharge threshold; f is a temperature correction coefficient; g is a thermal runaway battery proportionality coefficient; and h is a discharge rate growth coefficient.

[0013] As a preferred solution, the discharge rate d of the secondary treatment has a value range of 1C~3C, and when the calculated value of d is greater than 3, the value of d is taken as 3.

[0014] As a preferred solution, the secondary alarm trigger temperature threshold T alert has a value range of 45℃~120℃; The basic discharge threshold e has a value range of 1C~3C; The temperature correction coefficient f has a value range of 0.1~1; The thermal runaway battery proportionality coefficient g has a value range of 0.1~1; The discharge rate growth coefficient h has a value range of 1~5.

[0015] As a preferred solution, the calculation expression of the discharge rate corresponding to the discharge current of the tertiary treatment according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module, and the number of fault batteries is as follows:

[0016] In the formula, j is the discharge rate of the current; k1 is a safety coefficient; C rated is the rated charge and discharge rate of the energy storage battery; SOC is the current remaining capacity of the energy storage battery; SOC max is the charging cutoff remaining capacity of the energy storage system; SOC min is the discharging cutoff remaining capacity of the energy storage system; T max is the current highest temperature of the energy storage battery module; T alert3 is the tertiary alarm trigger temperature threshold; T thermal is the thermal runaway trigger temperature of the energy storage battery; and k2 is a correction coefficient.

[0017] As a preferred solution, the safety coefficient k1 has a value range of 0.1~5, and is specifically calibrated according to the type of the energy storage battery; The current remaining capacity SOC of the energy storage battery has a value of 0~100%; The correction coefficient k2 has a value range of 0.1~10.

[0018] In a second aspect, a device for inhibiting thermal runaway of an energy storage battery is provided, which is used to implement the method for inhibiting thermal runaway of an energy storage battery. The device comprises a plurality of thermocouples, each of which is configured to collect the temperature of each energy storage battery in an energy storage battery module in real time. A main controller, a variable resistor, a switch and a current monitor are connected between the positive and negative electrodes of the energy storage battery module through wires. The main controller compares the temperature collected by the thermocouples in real time with a plurality of preset temperature thresholds, and controls the on-off of the switch and adjusts the working parameters of the variable resistor according to the comparison result to implement a first-level treatment, a second-level treatment or a third-level treatment. The current monitor monitors the size of the discharge current, thereby achieving the inhibition of thermal runaway of the energy storage battery.

[0019] In a third aspect, a system for inhibiting thermal runaway of an energy storage battery is provided, which comprises: an energy storage battery temperature monitoring module configured to collect the temperature of the energy storage battery in real time, and compare the temperature with a plurality of preset temperature thresholds to obtain a comparison result; an energy storage battery thermal runaway grading treatment module configured to trigger a first-level treatment when a first-level treatment condition is met according to the obtained temperature comparison result, wherein the first-level treatment delays the increase of the internal temperature of the battery by discharging current; trigger a second-level treatment when a second-level treatment condition is met, wherein the second-level treatment increases the discharge rate of the current to a corresponding rate calculated according to the current thermal runaway condition of the energy storage battery; trigger a third-level treatment when a third-level treatment condition is met, wherein the discharge current of the third-level treatment controls the corresponding discharge rate according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module and the number of fault batteries; the levels of the first-level treatment, the second-level treatment and the third-level treatment are sequentially increased, and the inhibition of thermal runaway of the energy storage battery is achieved through the first-level treatment, the second-level treatment and the third-level treatment.

[0020] As a preferred scheme, the energy storage battery thermal runaway grading treatment module determines whether the first-level treatment condition is met by determining whether the temperature of the energy storage battery reaches a first temperature threshold or whether a first-level alarm signal is sent by the energy storage system; determines whether the second-level treatment condition is met by determining whether the temperature of the energy storage battery reaches a second temperature threshold or whether a battery safety valve opening signal is detected or a second-level alarm is sent by the energy storage system; and determines whether the third-level treatment condition is met by determining whether the temperature rise rate of one or more energy storage batteries in the energy storage battery module is greater than 1℃ / s or whether a third-level alarm is sent by the energy storage system.

[0021] As a preferred scheme, when the energy storage battery thermal runaway grading treatment module determines whether the temperature of the energy storage battery reaches the first temperature threshold, the value a of the first temperature threshold ranges from 50℃ to 120℃, and the discharge rate of the first-level treatment when discharging current ranges from 0.01C to 0.5C.

[0022] As a preferred scheme, when the thermal runaway grading disposal module of the energy storage battery determines whether the temperature of the energy storage battery reaches a second temperature threshold, the second temperature threshold has a value b in a range of a value a of the first temperature threshold to 250 DEG C, and the current discharge rate is calculated according to the current thermal runaway condition of the energy storage battery, and the calculation expression is as follows: h In the formula, d is the current discharge rate of the secondary disposal; T is the current average temperature of the energy storage battery module; T safe is the upper limit of the safe working temperature of the energy storage battery; T alert is the secondary alarm trigger temperature threshold; N abn is the number of energy storage batteries with abnormal temperature, which is equal to the number of single batteries whose temperature exceeds T alert ; N total is the total number of batteries of the energy storage battery module; e is the basic discharge threshold; f is the temperature correction coefficient; g is the thermal runaway battery proportion coefficient; and h is the discharge rate growth coefficient.

[0023] As a preferred scheme, when the thermal runaway grading disposal module triggers the tertiary disposal, the calculation expression of the discharge current corresponding discharge rate of the tertiary disposal according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module and the number of fault batteries is as follows:

[0024] In the formula, j is the current discharge rate of the tertiary disposal; k1 is the safety coefficient; C rated is the rated charge-discharge rate of the energy storage battery; SOC is the current remaining capacity of the energy storage battery; SOC max is the remaining capacity at the charge cutoff of the energy storage system; SOC min is the remaining capacity at the discharge cutoff of the energy storage system; T max is the current highest temperature of the energy storage battery module; T alert3 is the tertiary alarm trigger temperature threshold; T thermal is the thermal runaway trigger temperature of the energy storage battery; and k2 is the correction coefficient.

[0025] In a fourth aspect, an electronic device is provided, which comprises a processor and a memory, and the processor is configured to execute a computer program stored in the memory to implement the energy storage battery thermal runaway suppression method.

[0026] In a fifth aspect, a computer readable storage medium is provided, which stores at least one instruction, and the at least one instruction is executed by a processor to implement the energy storage battery thermal runaway suppression method.

[0027] Compared with the prior art, the first aspect of the present application has at least the following beneficial effects: The energy storage battery thermal runaway suppression method of the present application can effectively delay or terminate the thermal runaway process by monitoring the battery state parameters in real time, identifying the early characteristics of thermal runaway, and applying discharge currents of different intensities at different temperature rise stages.

[0028] Further, the secondary treatment of the energy storage battery thermal runaway suppression method of the present application calculates the discharge current ratio according to the thermal runaway condition of the energy storage battery, and the tertiary treatment controls the discharge current ratio according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module, and the number of faulty batteries, thereby achieving a balance between energy storage battery thermal runaway suppression and energy storage system energy consumption through coordinated optimization of discharge control and battery state of charge, and having strong engineering applicability.

[0029] It can be understood that the beneficial effects of the above-mentioned second to fourth aspects can be referred to the related description in the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor under the premise of the drawings.

[0031] Figure 1 The energy storage battery thermal runaway suppression method flowchart of the present application embodiment; Figure 2 The energy storage battery thermal runaway suppression device structure schematic diagram of the present application embodiment; Figure 3 The lithium iron phosphate energy storage battery module side view structure schematic diagram of the present application embodiment; Figure 4The application embodiment provides a front view structural schematic diagram of a lithium iron phosphate energy storage battery module. In the drawings: 1-thermocouple; 2-energy storage battery; 3-wire; 4-main controller; 5-variable resistor; 6-switch; 7-current monitor; 8-connection row. DETAILED DESCRIPTION

[0032] In the following description, specific details are set forth such as particular system configurations, techniques, etc., in order to provide a thorough understanding of the embodiments of the application. However, persons skilled in the art will understand that the application can be practiced without these specific details. In other instances, well-known structures, devices, circuits, and methods have not been described in detail in order to avoid obscuring the description of the application.

[0033] Regarding the lithium ion battery thermal runaway suppression technology, in recent years, some research has proposed an interface electron deprivation (IED) strategy (Wang Y, Feng X, Peng Y, et al. Reductive gas manipulation at early self-heating stage enables controllable battery thermal failure[J]. Joule, 2022, 6(12): 2810-2820) at the early stage of battery self-heating, that is, by applying a small discharge current through an external circuit, the parasitic reaction between the negative electrode and the electrolyte is suppressed, thereby delaying heat accumulation. However, this method is still in the preliminary research stage, and is mainly aimed at high-nickel ternary systems, and its application in lithium iron phosphate (LFP) batteries has not been systematically studied, especially the use of dynamic discharge strategies at different thermal runaway stages has not been reported. In view of this, the application embodiment proposes an energy storage battery thermal runaway suppression method to meet the demand for LFP battery thermal runaway suppression. By connecting a variable resistor in parallel to the energy storage battery module loop, the battery is discharged when the battery fails to suppress the hazards of battery thermal runaway. Based on this, a battery thermal runaway hierarchical suppression strategy based on discharge is constructed, and the discharge rate is dynamically regulated according to the battery temperature and SOC characteristics, the internal reaction of the battery is suppressed by slow discharge at the early stage of thermal runaway, and the SOC of the battery is reduced by fast discharge at the later stage, thereby reducing the maximum temperature and hazards of battery thermal runaway and avoiding the expansion of battery thermal runaway at the module level.

[0034] Please refer to Figure 1 The energy storage battery thermal runaway suppression method proposed in the application embodiment includes the following steps: S1, the temperature of the energy storage battery is collected in real time, and compared with a plurality of temperature thresholds set in advance to obtain a temperature comparison result; S2, according to the obtained temperature comparison result, triggering a first treatment when reaching a first treatment condition, the first treatment delaying the rise of the temperature inside the battery by discharging current; triggering a second treatment when reaching a second treatment condition, the second treatment increasing the rate of the current discharge to a corresponding rate calculated according to the current thermal runaway situation of the energy storage battery; triggering a third treatment when reaching a third treatment condition, the discharge current of the third treatment controlling the corresponding discharge rate according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module and the number of fault batteries; the levels of the first treatment, the second treatment and the third treatment are sequentially increased, and the energy storage battery thermal runaway is inhibited through the first treatment, the second treatment and the third treatment.

[0035] Further, the first treatment condition of the embodiment of the present application is that the temperature of the energy storage battery reaches a first temperature threshold or the energy storage system sends a first alarm signal; The second treatment condition is that the temperature of the energy storage battery reaches a second temperature threshold or a battery safety valve opening signal is detected or the energy storage system sends a second alarm; The third treatment condition is that the temperature rise rate of more than one energy storage battery in the energy storage battery module is greater than 1℃ / s or the energy storage system occurs a third alarm.

[0036] In a possible implementation, the first temperature threshold value a of the embodiment of the present application ranges from 50℃ to 120℃, and the discharge rate of the first treatment when discharging current is 0.01C to 0.5C.

[0037] The second temperature threshold value b of the embodiment of the present application ranges from the first temperature threshold value a to 250℃, and the discharge rate of the current according to the current thermal runaway situation of the energy storage battery is calculated according to the following expression: h In the formula, d is the discharge rate of the second treatment; T is the current average temperature of the energy storage battery module; T safe is the upper limit of the safe working temperature of the energy storage battery; T alert is the second alarm triggering temperature threshold; N abn is the number of energy storage batteries with abnormal temperature, equal to the number of single batteries whose temperature exceeds T alert ; N total is the total number of energy storage batteries in the module; e is the basic discharge threshold; f is the temperature correction coefficient; g is the thermal runaway battery proportion coefficient; h is the discharge rate growth coefficient.

[0038] Further, the discharge rate d of the second treatment is in C, and the value range is 1C to 3C, and when the calculated d value is greater than 3, the d value is taken as 3; The second alarm trigger temperature threshold T alert The value range of the temperature correction coefficient f is 0.1-1. The value range of the basic discharge threshold e is 1C-3C. The value range of the temperature correction coefficient f is 0.1-1. The value range of the thermal runaway battery proportion coefficient g is 0.1-1. The value range of the discharge rate growth coefficient h is 1-5.

[0039] In a possible implementation, the calculation expression of the discharge rate corresponding to the discharge current of the third treatment according to the real-time residual capacity SOC of the battery, the temperature distribution gradient change in the module and the number of fault batteries is as follows:

[0040] In the formula, j is the current discharge rate of the third treatment; k1 is a safety factor; C rated is the rated charge and discharge rate of the energy storage battery; SOC is the current residual capacity of the energy storage battery; SOC max is the charging cutoff residual capacity of the energy storage system; SOC min is the discharging cutoff residual capacity of the energy storage system; T max is the current highest temperature of the energy storage battery module; T alert3 is the third alarm trigger temperature threshold; T thermal is the thermal runaway trigger temperature of the energy storage battery; and k2 is a correction coefficient.

[0041] Further, the value range of the safety factor k1 is 0.1-5, which is specifically calibrated according to the type of the energy storage battery. The value of the current residual capacity SOC of the energy storage battery is 0-100%. The value range of the correction coefficient k2 is 0.1-10.

[0042] Please refer to Figures 2 to 4The embodiment of the present application also provides a thermal runaway inhibition device of energy storage battery, which is used for realizing the thermal runaway inhibition method of energy storage battery, and is suitable for a lithium iron phosphate energy storage battery module. The thermal runaway inhibition device of energy storage battery comprises a plurality of thermocouples 1, each of which is used for collecting the temperature of each energy storage battery 2 in the energy storage battery module in real time. Each energy storage battery 2 is connected to form the energy storage battery module through a connecting row 8. A main controller 4, a variable resistor 5, a switch 6 and a current monitor 7 are connected between the positive and negative electrodes of the energy storage battery module through wires 3. The main controller 4 compares the temperature collected by the thermocouples 1 in real time with a plurality of preset temperature thresholds, and controls the on-off of the switch 6 and adjusts the working parameters of the variable resistor 5 according to the temperature comparison result to realize first-level disposal, second-level disposal or third-level disposal. The current monitor 7 monitors the size of the discharge current, so as to realize the thermal runaway inhibition of the energy storage battery.

[0043] Another embodiment of the present application also provides a thermal runaway inhibition system of energy storage battery, which comprises: An energy storage battery temperature monitoring module is used for collecting the temperature of the energy storage battery in real time, comparing the temperature with a plurality of preset temperature thresholds, and obtaining a temperature comparison result. An energy storage battery thermal runaway grading disposal module is used for triggering first-level disposal when a first-level disposal condition is reached according to the obtained temperature comparison result, discharging current is applied to delay the temperature rise in the battery; triggering second-level disposal when a second-level disposal condition is reached, and the discharge current is increased to a corresponding rate calculated according to the current thermal runaway condition of the energy storage battery; triggering third-level disposal when a third-level disposal condition is reached, and the discharge current of the third-level disposal is controlled according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module and the number of fault batteries to control the corresponding discharge rate; and the levels of the first-level disposal, the second-level disposal and the third-level disposal are sequentially increased, so as to realize the thermal runaway inhibition of the energy storage battery through the first-level disposal, the second-level disposal and the third-level disposal.

[0044] In a possible implementation, the energy storage battery thermal runaway grading disposal module determines whether the first-level disposal condition is reached, that is, the temperature of the energy storage battery reaches a first temperature threshold or the energy storage system sends a first-level alarm signal; determines whether the second-level disposal condition is reached, that is, the temperature of the energy storage battery reaches a second temperature threshold, a battery safety valve opening signal is detected or the energy storage system sends a second-level alarm; and determines whether the third-level disposal condition is reached, that is, the temperature rise rate of more than one energy storage battery in the energy storage battery module is greater than 1℃ / s or the energy storage system sends a third-level alarm.

[0045] Further, in a possible implementation, when the energy storage battery thermal runaway hierarchical treatment module determines whether the temperature of the energy storage battery reaches the first temperature threshold, the value a of the first temperature threshold ranges from 50℃ to 120℃, and the discharge rate of the first-level treatment when the current discharge is applied ranges from 0.01C to 0.5C.

[0046] In a possible implementation, when the energy storage battery thermal runaway hierarchical treatment module determines whether the temperature of the energy storage battery reaches the second temperature threshold, the value b of the second temperature threshold ranges from the value a of the first temperature threshold to 250℃, and the discharge rate of the current calculated according to the current thermal runaway condition of the energy storage battery is expressed as follows: h In the formula, d is the current discharge rate of the second-level treatment, T is the current average temperature of the energy storage battery module, T safe is the upper limit of the safe working temperature of the energy storage battery, T alert is the second-level alarm trigger temperature threshold, N abn is the number of energy storage batteries with abnormal temperature, which is equal to the number of single batteries whose temperature exceeds T alert , N total is the total number of batteries of the energy storage battery module, e is the basic discharge threshold, f is the temperature correction coefficient, g is the thermal runaway battery proportion coefficient, and h is the discharge rate growth coefficient.

[0047] Further, the unit of the current discharge rate d of the second-level treatment is C, and the value ranges from 1C to 3C. When the calculated value of d is greater than 3, the value of d is taken as 3. The value range of the second-level alarm trigger temperature threshold T alert ranges from 45℃ to 120℃. The unit of the basic discharge threshold e is C, and the value ranges from 1C to 3C. The value range of the temperature correction coefficient f ranges from 0.1 to 1. The value range of the thermal runaway battery proportion coefficient g ranges from 0.1 to 1. The value range of the discharge rate growth coefficient h ranges from 1 to 5.

[0048] In a possible implementation, when the energy storage battery thermal runaway hierarchical treatment module triggers the third-level treatment, the calculation expression of the discharge current corresponding discharge rate of the third-level treatment according to the real-time remaining capacity SOC of the battery, the temperature distribution gradient change in the module, and the number of fault batteries is as follows:

[0049] In the formula, j is the current discharge rate of the third-level treatment, k1 is the safety coefficient, C ratedThe rated charge / discharge rate of the energy storage battery; SOC is the current remaining capacity of the energy storage battery; SOC max Charge the energy storage system to the point where the remaining power is depleted; SOC min The remaining energy level of the energy storage system is discharged and cut off; T max This is the highest current temperature of the energy storage battery module; T alert3 The temperature threshold for triggering a level 3 alarm; T thermal K is the thermal runaway trigger temperature of the energy storage battery; k2 is the correction coefficient.

[0050] Furthermore, the safety factor k1 ranges from 0.1 to 5, and is calibrated according to the type of energy storage battery. The current remaining charge (SOC) of the energy storage battery ranges from 0% to 100%. The correction coefficient k2 ranges from 0.1 to 10.

[0051] This invention provides a multi-stage dynamic discharge-based thermal runaway suppression scheme for lithium iron phosphate batteries, aiming to reduce the maximum temperature and hazards of battery thermal runaway and prevent large-scale accidents in energy storage systems. By applying discharge currents at different rates at different stages of thermal runaway and adjusting the scheme in conjunction with the battery's state of charge and the stage of thermal runaway, the reaction path is effectively blocked before thermal runaway occurs, and the hazards of thermal runaway are reduced afterward, achieving the goal of suppressing thermal runaway development from its source. This invention aims to enhance the active safety protection capabilities of energy storage systems, suppress the development of battery thermal runaway while reducing energy loss, avoid the lag of traditional end-of-pipe protection measures, and provide key technical support for the development of high-safety lithium-ion battery energy storage systems.

[0052] Another embodiment of the present invention provides an electronic device including a processor and a memory, the processor being used to execute a computer program stored in the memory to implement the aforementioned method for suppressing thermal runaway of an energy storage battery.

[0053] Another embodiment of the present invention provides a computer-readable storage medium storing at least one instruction that, when executed by a processor, implements the energy storage battery thermal runaway suppression method.

[0054] The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable storage medium can include any entity or device capable of carrying the computer program code, a medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory, a random access memory, an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals. For ease of explanation, the above content only shows the parts related to the embodiments of the present invention; for specific technical details not disclosed, please refer to the method section of the embodiments of the present invention. This computer-readable storage medium is non-transitory and can be stored in storage devices formed by various electronic devices, enabling the execution process described in the method of the embodiments of the present invention.

[0055] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0056] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0057] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0058] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for suppressing thermal runaway in an energy storage battery, characterized in that, include: The temperature of the energy storage battery is collected in real time and compared with multiple preset temperature thresholds to obtain the temperature comparison results; Based on the obtained temperature comparison results, a first-level treatment is triggered when the first-level treatment conditions are met. The first-level treatment delays the rise in the internal temperature of the battery by applying current discharge. When the conditions for secondary disposal are met, secondary disposal is triggered, which increases the current discharge rate to the corresponding rate calculated based on the current thermal runaway status of the energy storage battery. When the conditions for Level 3 treatment are met, Level 3 treatment is triggered. The discharge current of Level 3 treatment is controlled according to the real-time remaining charge (SOC) of the battery, the temperature distribution gradient change within the module, and the number of faulty batteries. The levels of Level 1, Level 2, and Level 3 treatment are sequentially increased, and thermal runaway of the energy storage battery is suppressed through Level 1, Level 2, and Level 3 treatment.

2. The method for suppressing thermal runaway of an energy storage battery according to claim 1, characterized in that, The first-level handling condition is when the temperature of the energy storage battery reaches the first temperature threshold or the energy storage system issues a first-level alarm signal. The secondary handling conditions are: the temperature of the energy storage battery reaches the second temperature threshold, or a battery safety valve opening signal is detected, or the energy storage system issues a secondary alarm. The third-level handling conditions are: the temperature rise rate of more than one energy storage battery inside the energy storage battery module is greater than 1℃ / s, or the energy storage system triggers a third-level alarm.

3. The method for suppressing thermal runaway of an energy storage battery according to claim 2, characterized in that, The first temperature threshold value a ranges from 50℃ to 120℃, and the discharge rate of the first-level treatment when applying current discharge is 0.01C to 0.5C.

4. The method for suppressing thermal runaway of an energy storage battery according to claim 3, characterized in that, The value b of the second temperature threshold ranges from the value a of the first temperature threshold to 250°C. The discharge rate is calculated based on the current thermal runaway condition of the energy storage battery according to the following expression: h In the formula, d is the current discharge rate of the secondary treatment; T represents the current average temperature of the energy storage battery module; T safe This refers to the upper limit of the safe operating temperature for energy storage batteries. T alert The temperature threshold for triggering a level 2 alarm; N abn The number of energy storage batteries with abnormal temperatures is equal to the number of batteries with temperatures exceeding T. alert The number of individual cells; N total denoted as the total number of batteries in the energy storage battery module; e is the basic discharge threshold; f is the temperature correction coefficient; g is the thermal runaway battery proportion coefficient; and h is the discharge rate growth coefficient.

5. The method for suppressing thermal runaway of an energy storage battery according to claim 4, characterized in that, The current discharge rate d for the secondary treatment ranges from 1C to 3C. When the calculated d value is greater than 3, the d value is set to 3.

6. The method for suppressing thermal runaway of an energy storage battery according to claim 4, characterized in that, The secondary alarm triggering temperature threshold T alert The value range is 45℃~120℃; The basic discharge threshold e ranges from 1C to 3C; The temperature correction coefficient f ranges from 0.1 to 1; The proportional coefficient g of the thermal runaway battery ranges from 0.1 to 1; The value of the discharge rate growth coefficient h ranges from 1 to 5.

7. The method for suppressing thermal runaway of an energy storage battery according to claim 4, characterized in that, The calculation formula for the discharge rate corresponding to the discharge current controlled by the three-level handling based on the real-time remaining battery charge (SOC), the temperature distribution gradient change within the module, and the number of faulty batteries is as follows: In the formula, j is the discharge rate of the third-level treatment; k1 is the safety factor; C rated The rated charge / discharge rate of the energy storage battery; SOC is the current remaining capacity of the energy storage battery; SOC max Charge the energy storage system to the point where the remaining power is depleted; SOC min The remaining energy level of the energy storage system is discharged and cut off; T max This is the highest current temperature of the energy storage battery module; T alert3 The temperature threshold for triggering a level 3 alarm; T thermal K is the thermal runaway trigger temperature of the energy storage battery; k2 is the correction coefficient.

8. The method for suppressing thermal runaway of an energy storage battery according to claim 7, characterized in that, The safety factor k1 ranges from 0.1 to 5, and is calibrated according to the type of energy storage battery. The current remaining charge (SOC) of the energy storage battery ranges from 0% to 100%. The correction coefficient k2 ranges from 0.1 to 10.

9. A thermal runaway suppression device for an energy storage battery, characterized in that, The method for suppressing thermal runaway of an energy storage battery as described in any one of claims 1 to 8 includes multiple thermocouples (1), each thermocouple (1) acquiring the temperature of each energy storage battery (2) in the energy storage battery module in real time. The positive and negative terminals of the energy storage battery module are connected by wires (3) to a main controller (4), a variable resistor (5), a switch (6), and a current monitor (7). The main controller (4) receives the temperature acquired in real time by the thermocouples (1), compares it with multiple preset temperature thresholds, and controls the switching on and off of the switch (6) and adjusts the working parameters of the variable resistor (5) according to the temperature comparison results to achieve first-level, second-level, or third-level treatment. The current monitor (7) monitors the magnitude of the discharge current to achieve thermal runaway suppression of the energy storage battery.

10. A thermal runaway suppression system for an energy storage battery, characterized in that, include: The energy storage battery temperature monitoring module is used to collect the temperature of the energy storage battery in real time and compare it with multiple preset temperature thresholds to obtain the temperature comparison results. The thermal runaway graded handling module for energy storage batteries is used to trigger a first-level handling when the first-level handling conditions are met based on the obtained temperature comparison results. The first-level handling delays the rise in internal battery temperature by applying current discharge. When the conditions for secondary disposal are met, secondary disposal is triggered, which increases the current discharge rate to the corresponding rate calculated based on the current thermal runaway status of the energy storage battery. When the conditions for Level 3 treatment are met, Level 3 treatment is triggered. The discharge current of Level 3 treatment is controlled according to the real-time remaining charge (SOC) of the battery, the temperature distribution gradient change within the module, and the number of faulty batteries. The levels of Level 1, Level 2, and Level 3 treatment are sequentially increased, and thermal runaway of the energy storage battery is suppressed through Level 1, Level 2, and Level 3 treatment.

11. The energy storage battery thermal runaway suppression system according to claim 10, characterized in that, The thermal runaway classification and handling module for energy storage batteries determines whether the first-level handling condition is met when the temperature of the energy storage battery reaches the first temperature threshold or the energy storage system issues a first-level alarm signal; it determines whether the second-level handling condition is met when the temperature of the energy storage battery reaches the second temperature threshold or a battery safety valve opening signal is detected or the energy storage system issues a second-level alarm; and it determines whether the third-level handling condition is met when there is a temperature rise rate greater than 1℃ / s for more than one energy storage battery inside the energy storage battery module or the energy storage system issues a third-level alarm.

12. The energy storage battery thermal runaway suppression system according to claim 11, characterized in that, When the thermal runaway graded treatment module of the energy storage battery determines whether the temperature of the energy storage battery has reached the first temperature threshold, the value of the first temperature threshold a is in the range of 50℃~120℃, and the discharge rate of the first treatment when the current is applied is 0.01C~0.5C.

13. The energy storage battery thermal runaway suppression system according to claim 12, characterized in that, When the thermal runaway classification and handling module of the energy storage battery determines whether the temperature of the energy storage battery has reached the second temperature threshold, the value b of the second temperature threshold ranges from the value a of the first temperature threshold to 250°C. The discharge rate is calculated according to the following expression based on the current thermal runaway status of the energy storage battery: h In the formula, d is the current discharge rate of the secondary treatment; T represents the current average temperature of the energy storage battery module; T safe This refers to the upper limit of the safe operating temperature for energy storage batteries. T alert The temperature threshold for triggering a level 2 alarm; N abn The number of energy storage batteries with abnormal temperatures is equal to the number of batteries with temperatures exceeding T. alert The number of individual cells; N total denoted as the total number of batteries in the energy storage battery module; e is the basic discharge threshold; f is the temperature correction coefficient; g is the thermal runaway battery proportion coefficient; and h is the discharge rate growth coefficient.

14. The energy storage battery thermal runaway suppression system according to claim 13, characterized in that, When the thermal runaway graded handling module of the energy storage battery triggers the third-level handling, the calculation expression for the discharge rate corresponding to the discharge current is as follows: The third-level handling is based on the real-time remaining charge (SOC) of the battery, the temperature distribution gradient change within the module, and the number of faulty batteries. In the formula, j is the discharge rate of the third-level treatment; k1 is the safety factor; C rated The rated charge / discharge rate of the energy storage battery; SOC is the current remaining capacity of the energy storage battery; SOC max Charge the energy storage system to the point where the remaining power is depleted; SOC min The remaining energy level of the energy storage system is discharged and cut off; T max This is the highest current temperature of the energy storage battery module; T alert3 The temperature threshold for triggering a level 3 alarm; T thermal K is the thermal runaway trigger temperature of the energy storage battery; k2 is the correction coefficient.

15. An electronic device, characterized in that, It includes a processor and a memory, the processor being used to execute a computer program stored in the memory to implement the energy storage battery thermal runaway suppression method as described in any one of claims 1 to 8.

16. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one instruction, which, when executed by a processor, implements the energy storage battery thermal runaway suppression method as described in any one of claims 1 to 8.

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