Power battery thermal runaway early warning method and device, electronic equipment and electric vehicle

Abstract

The application discloses a thermal runaway early warning method and device of a power battery, electronic equipment and an electric vehicle, and relates to the technical field of power batteries. The method comprises the following steps: acquiring accumulated power of the power battery and cooling energy used for cooling the power battery within a preset time; acquiring heat generation of unit power of the power battery according to the accumulated power and the cooling energy; and performing thermal runaway early warning on the power battery according to the heat generation of unit power. Therefore, the accuracy of the thermal runaway early warning can be effectively improved, and the method has high reliability and low cost.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle technology, and in particular to a method for early warning of thermal runaway of a power battery, a device for early warning of thermal runaway of a power battery, on-board electronic equipment, and an electric vehicle. Background Technology

[0002] According to the latest national standard GB 38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles", the battery pack or system should provide a preliminary warning signal (serving the vehicle's thermal accident alarm) 5 minutes before thermal runaway of a single battery causes heat diffusion and leads to a hazard in the passenger compartment, to remind occupants to evacuate. Therefore, the safety monitoring and timely alarm of the battery system are important factors in the safety of electric vehicles.

[0003] In related technologies, invention patent CN111007461A discloses a lithium battery thermal runaway location system based on sound signals. This system collects sound signals from within the battery pack using a microphone array and locates the target battery by receiving the time delay of the sound signal indicating the safety valve opening. However, because the battery pack is installed in the vehicle's chassis, it may receive sound signals from the ground, tires, or inside the vehicle while the vehicle is in motion. These chaotic sound signals can lead to incorrect judgments; that is, sound acquisition within the battery is easily affected by external interference, resulting in low accuracy and potentially causing misjudgments or missed detections. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this invention is to provide a method for early warning of thermal runaway in power batteries, which can effectively improve the accuracy of thermal runaway early warning, has high reliability, and is low in cost.

[0005] The second objective of this invention is to provide an in-vehicle electronic device.

[0006] The third objective of this invention is to provide an electric vehicle.

[0007] The fourth objective of this invention is to provide a thermal runaway early warning device for a power battery.

[0008] To achieve the above objectives, a first aspect of the present invention provides a method for early warning of thermal runaway of a power battery. The method includes: acquiring the cumulative charge of the power battery within a preset time and the cooling energy used to cool the power battery; acquiring the heat generated per unit charge of the power battery based on the cumulative charge and the cooling energy; and providing early warning of thermal runaway of the power battery based on the heat generated per unit charge.

[0009] The thermal runaway early warning method for power batteries according to embodiments of the present invention obtains the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, obtains the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy, and performs thermal runaway early warning for the power battery based on the heat generation per unit charge. This effectively improves the accuracy of thermal runaway early warning, and has high reliability and low cost.

[0010] According to one embodiment of the present invention, obtaining the cumulative charge of a power battery within a preset time includes: obtaining the voltage and current of the power battery; and calculating the cumulative charge based on the voltage, current and preset time.

[0011] According to one embodiment of the present invention, the accumulated power includes the charging power or discharging power of the power battery.

[0012] According to one embodiment of the present invention, obtaining the cooling energy used for cooling the power battery within a preset time includes: obtaining the coolant inlet temperature and coolant outlet temperature of the power battery; and calculating the cooling energy based on the coolant inlet temperature, coolant outlet temperature and preset time.

[0013] According to one embodiment of the present invention, obtaining the heat generation per unit charge of a power battery based on accumulated charge and cooling energy includes: obtaining the ratio of cooling energy to accumulated charge to obtain the heat generation per unit charge of the power battery.

[0014] According to one embodiment of the present invention, thermal runaway warning of a power battery is provided based on the heat generated per unit of electricity, including: if the heat generated per unit of electricity is greater than a preset threshold, then a thermal runaway warning is provided.

[0015] To achieve the above objectives, a second aspect of the present invention provides an in-vehicle electronic device, including: a memory, a processor, and a thermal runaway warning program for a power battery stored in the memory and executable on the processor. When the processor executes the program, it implements the aforementioned thermal runaway warning method for the power battery.

[0016] According to the vehicle-mounted electronic device of the present invention, by acquiring the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, and acquiring the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy, and performing thermal runaway warning for the power battery based on the heat generation per unit charge, the accuracy of thermal runaway warning can be effectively improved, and the reliability and cost are high.

[0017] To achieve the above objectives, a third aspect of the present invention provides an electric vehicle including the on-board electronic equipment described in the above embodiments.

[0018] According to the present invention, an electric vehicle can effectively improve the accuracy of thermal runaway warning by acquiring the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, and by acquiring the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy, and by providing thermal runaway warning for the power battery based on the heat generation per unit charge. This method is highly reliable and low in cost.

[0019] To achieve the above objectives, a fourth aspect of the present invention provides a thermal runaway early warning device for a power battery. The device includes: an acquisition module, configured to acquire the cumulative charge of the power battery within a preset time and the cooling energy used to cool the power battery, and to acquire the heat generated per unit charge of the power battery based on the cumulative charge and the cooling energy; and an alarm module, configured to provide a thermal runaway early warning for the power battery based on the heat generated per unit charge.

[0020] According to an embodiment of the present invention, a thermal runaway early warning device for a power battery acquires the accumulated charge of the power battery and the cooling energy used to cool the power battery within a preset time by an acquisition module, and acquires the heat generated per unit charge of the power battery based on the accumulated charge and the cooling energy, and provides a thermal runaway early warning for the power battery based on the heat generated per unit charge by an alarm module. This effectively improves the accuracy of the thermal runaway early warning, and is highly reliable and low in cost.

[0021] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a vehicle charging monitoring system according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of a battery cooling monitoring system according to an embodiment of the present invention;

[0024] Figure 3 A flowchart of a power battery thermal runaway early warning method according to an embodiment of the present invention;

[0025] Figure 4 A flowchart of a power battery thermal runaway early warning method according to another embodiment of the present invention;

[0026] Figure 5 This is a structural block diagram of an in-vehicle electronic device according to an embodiment of the present invention;

[0027] Figure 6 This is a structural block diagram of an electric vehicle according to an embodiment of the present invention;

[0028] Figure 7This is a structural block diagram of a power battery thermal runaway early warning device according to an embodiment of the present invention. Detailed Implementation

[0029] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0030] The following description, with reference to the accompanying drawings, describes the thermal runaway early warning method for power batteries, the thermal runaway early warning device for power batteries, the vehicle-mounted electronic equipment, and the electric vehicle provided by embodiments of the present invention.

[0031] It should be noted that a lithium battery thermal runaway localization system based on acoustic signals has been proposed in related technologies. This system collects acoustic signals within the battery pack by arranging a microphone array inside the pack. It then uses a combination of a four-element planar microphone matrix, a signal acquisition module, an analysis and recognition module, and a power supply module to identify the safety valve opening sound signal within the battery pack. Furthermore, it employs a time-delay localization algorithm based on the collected safety valve opening sound signal to pinpoint the exact location of the target battery and implements fire-fighting measures for the identified cells. However, this localization system has the following drawbacks:

[0032] First, because the battery pack is installed in the vehicle's chassis, it may receive sound signals from the ground, tires, or the interior of the vehicle while the vehicle is in motion. These chaotic sound signals can lead to misjudgments; that is, the sound acquisition within the battery is easily affected by external interference, resulting in low accuracy. This could cause the vehicle to mistakenly activate fire suppression systems or fail to detect a fault when it occurs. Second, since this solution locates thermal runaway lithium batteries by detecting the opening status of the cell's safety valve, the fault detection is only confirmed after the cell's safety valve has opened. When the battery casing is subjected to impacts, compression, or other external forces, this solution cannot detect the fault and may miss the optimal time for safe relocation. Third, because an additional sound acquisition device needs to be installed inside the battery pack, along with sound-insulating battery pack materials, this directly increases the production cost of the battery pack.

[0033] Based on this, this application provides a method for early warning of thermal runaway in power batteries. This method can effectively improve the accuracy of thermal runaway early warning, and has high reliability and low cost.

[0034] The thermal runaway early warning method for power batteries provided in this application can be implemented through a vehicle charging monitoring system and a battery cooling monitoring system.

[0035] Figure 1 This is a schematic diagram of a vehicle charging monitoring system according to an embodiment of the present invention, with reference to... Figure 1 As shown, the vehicle charging monitoring system 100 may include a vehicle 110 and a charging cabinet 120 for charging the vehicle 110. The vehicle 110 is equipped with an air conditioning compressor 111 and a battery pack 112. The battery pack 112 is equipped with a voltage and current sensor 113 for collecting real-time signals of the voltage and current of the battery pack 112. It should be noted that this vehicle charging monitoring system 100 is a monitoring system for the battery pack 112. Since the voltage and current sensor 113 in the battery pack 112 only collects real-time signals of the voltage and current of the battery pack 112, the power consumption of high-voltage electrical appliances such as the air conditioning compressor 111 in the vehicle is not considered, thus obtaining a more accurate accumulated charge of the power battery.

[0036] Figure 2 This is a schematic diagram of a battery cooling monitoring system according to an embodiment of the present invention, with reference to... Figure 2 As shown, the battery cooling monitoring system 200 may include a battery cooling system 210, a water pump 220, a battery pack 230, an inlet temperature sensor 240 for detecting the inlet temperature of the battery pack coolant pipe, and an outlet temperature sensor 250 for detecting the outlet temperature of the battery pack coolant pipe. The battery cooling system 210 includes a compressor 211, a condenser 212, an expansion valve 213, and a heat exchanger 214. This battery cooling system 210 provides cooling to the system using the principle of air conditioning, and the heat exchanger 214 provides the cooling source for the downstream battery pack 230. Specifically, the coolant circulates between the heat exchanger 214 and the battery pack 230 under the action of the water pump 220, transferring heat from the battery pack 230 to the heat exchanger 214, and finally exchanging heat with the air through the condenser 212.

[0037] Figure 3 Here is a flowchart of a power battery thermal runaway early warning method according to an embodiment of the present invention, with reference to... Figure 3 As shown, the thermal runaway early warning method for this power battery may include the following steps:

[0038] Step S301: Obtain the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time.

[0039] Specifically, since the cumulative charge of the power battery (the change in charge within the power battery) and the cooling energy used to cool the power battery (the heat exchanged during cooling) are parameters directly related to thermal control, and are respectively related to charging / discharging time and cooling time, a preset time period is selected, and the cumulative charge of the power battery and the cooling energy used to cool the power battery within this preset time period are obtained. It should be noted that the cumulative charge of the power battery here can be not only the charge amount during parking charging, but also the discharge amount during driving discharge.

[0040] In one embodiment, obtaining the cumulative charge of the power battery within a preset time period includes: obtaining the voltage and current of the power battery; and calculating the cumulative charge based on the voltage, current, and preset time period.

[0041] In other words, if thermal runaway warning of the power battery is to be issued during charging, the voltage and current sensors in the battery pack can be used to collect real-time voltage and current signals of the battery pack during charging to obtain the charging voltage U. 充电 and charging current I 充电 The charging power P of the battery is then calculated by multiplying the two values. 充电 ,Right now

[0042] P 充电 =U 充电 ×I 充电

[0043] Then the charging power P 充电 With time t 充电 Multiply to calculate the charging capacity Q of the battery pack. 充电 ,Right now

[0044] Q 充电 =P 充电 ×t 充电

[0045] If thermal runaway warning of the power battery is to be issued during discharge, the voltage and current sensors in the battery pack can be used to collect real-time voltage and current signals of the battery pack during discharge to obtain the discharge voltage U. 放电 and discharge current I 放电 The battery's discharge power P is calculated by multiplying the voltage and current. 放电 ,Right now

[0046] P 放电 =U 放电 ×I 放电

[0047] Then the discharge power P 放电 The discharge capacity Q of the battery pack is calculated by multiplying it by time. 放电 ,Right now

[0048] Q 放电 =P 放电 ×t 放电

[0049] Understandably, since this method of obtaining power does not involve the power consumption of high-voltage electrical appliances such as air conditioning compressors in electric vehicles, it can provide a more accurate estimate of the charging or discharging power.

[0050] In one embodiment, obtaining the cooling energy used to cool the power battery within a preset time includes: obtaining the coolant inlet temperature and coolant outlet temperature of the power battery; and calculating the cooling energy based on the coolant inlet temperature, coolant outlet temperature, and preset time.

[0051] Specifically, by obtaining the inlet and outlet temperatures of the coolant in the power battery, the cooling power of the power battery can be calculated using the following formula:

[0052] P 冷却 =(T2-T1)Q 冷却液 C

[0053] Among them, P 冷却 T1 is the cooling power of the power battery, T2 is the coolant inlet temperature of the power battery, and Q is the coolant outlet temperature of the power battery. 冷却液 Let C be the flow rate of the coolant in the cooling pipes, and C be the specific heat capacity of the coolant. The cooling energy Q of the power battery... 冷却 It can be obtained through the following formula:

[0054] Q 冷却 =∫P 冷却 dt

[0055] Among them, Q 冷却 Let t represent the cooling energy of the power battery and t represent the cooling time. It should be noted that during the charging and discharging processes, the current flowing through the battery generates heat, causing the battery temperature to gradually rise. The cooling capacity generated by the battery cooling system is used to offset the heat generated by the battery pack, thus maintaining the battery temperature. Therefore, the cooling energy generated by the battery cooling system is equal to the heat generated by the battery pack; hence, the heat generated by the battery pack can be reflected by the cooling energy generated by the battery cooling system.

[0056] Furthermore, since the specific heat capacity C of the coolant is a constant, and the water pump, piping, and cooler related to the coolant flow rate are relatively fixed, the coolant flow rate Q... 冷却液 It can also be considered a constant. Therefore, the cooling power P of the power battery can be calculated simply by obtaining the coolant inlet temperature T1 and coolant outlet temperature T2. 冷却 .

[0057] Step S302: Obtain the heat generated per unit charge of the power battery based on the accumulated charge and cooling energy.

[0058] The method of obtaining the heat generation per unit charge of the power battery based on the accumulated charge and cooling energy may include obtaining the ratio of cooling energy to accumulated charge to obtain the heat generation per unit charge of the power battery.

[0059] Specifically, the heat generated per unit of electricity refers to the heat generated corresponding to a unit change in electricity (unit charging or unit discharging) in the power battery within a preset time. Since the cooling energy generated by the battery cooling system is equal to the heat generated by the battery pack when the battery temperature is stable, the heat generated per unit of electricity in the power battery can be expressed as the ratio of the cooling energy of the power battery to the accumulated electricity.

[0060] In other words, the charging level Q can be obtained through the vehicle's charge / discharge monitoring system while it is charging. 充电 And obtain the cooling energy Q through the battery cooling monitoring system. 冷却 Then, the heat generated per unit of electricity is obtained using the following formula.

[0061]

[0062] The charging level Q can also be obtained through the vehicle's charging and discharging monitoring system while the vehicle is discharging. 放电 And obtain the cooling energy Q through the battery cooling monitoring system. 冷却 Then, the heat generated per unit of electricity is obtained using the following formula.

[0063]

[0064] Among them, the heat generated per unit of electricity It is related to the battery's heat dissipation performance, but not to time, and can be used to measure battery heat dissipation.

[0065] Step S303: Provide a thermal runaway warning for the power battery based on the heat generated per unit of electricity.

[0066] Specifically, when an internal fault occurs in the battery (such as electrolyte crystallization), it leads to an increase in the battery's internal resistance. In this case, during parking charging or driving discharging, the heat generated per unit charge of the battery pack increases. The heat generated per unit charge of the battery pack will gradually increase; therefore, the heat generated per unit charge of the battery pack will increase. By comparing the results, early warnings can be issued for battery thermal runaway.

[0067] In one embodiment, thermal runaway warning for the power battery is provided based on the heat generated per unit of electricity, including: if the heat generated per unit of electricity exceeds a preset threshold, then a thermal runaway warning is provided.

[0068] In other words, the heat generated per unit charge of the battery pack When the temperature is low, such as below a preset threshold, the battery is determined to be in a normal state, and the system only needs to continue monitoring. When the heat generated per unit charge of the battery pack... If the temperature is too high, such as exceeding a preset threshold, the battery is determined to be in an abnormal state. A thermal runaway warning can be displayed on the vehicle's instrument panel to remind the user to have the battery inspected as soon as possible.

[0069] Therefore, the thermal runaway early warning method for power batteries according to embodiments of the present invention, compared with related technologies, is not affected by external sound signals, effectively improving the accuracy of thermal runaway early warning, and its reliability is not reduced by external impacts on the battery casing. At the same time, since it does not require additional sound acquisition equipment or sound-insulating battery pack materials, it has a significant cost advantage.

[0070] The present invention will be further explained and illustrated below through a specific embodiment. Figure 4 Here is a flowchart of the thermal runaway early warning method for a power battery according to this embodiment, with reference to... Figure 4 As shown, the thermal runaway early warning method for this power battery includes the following steps:

[0071] Step S401: Real-time acquisition of battery pack voltage and current.

[0072] Step S402: Calculate the cumulative charge of the power battery within a preset time period.

[0073] Step S403: Obtain the coolant inlet temperature and coolant outlet temperature.

[0074] Step S404: Calculate the difference between the coolant inlet temperature and the coolant outlet temperature.

[0075] Step S405: Calculate the cooling energy of the power battery within a preset time.

[0076] Step S406: Calculate the heat generated per unit of electricity.

[0077] Step S407: Determine whether the heat generated per unit of electricity is greater than the threshold. If yes, proceed to step S408; otherwise, proceed to step S409.

[0078] Step S408: Remind the user to have the battery inspected as soon as possible.

[0079] Step S409: Continue monitoring.

[0080] It should be understood that, although Figure 3-4 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 3-4At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0081] In summary, the thermal runaway early warning method for power batteries according to embodiments of the present invention obtains the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, obtains the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy, and provides thermal runaway early warning for the power battery based on the heat generation per unit charge. This effectively improves the accuracy of thermal runaway early warning, and is highly reliable and low in cost.

[0082] Figure 5 This is a structural block diagram of an in-vehicle electronic device according to an embodiment of the present invention. (Reference) Figure 5 As shown, the vehicle-mounted electronic device 500 includes: a memory 501, a processor 502, and a power battery thermal runaway warning program stored in the memory 501 and capable of running on the processor 502. When the processor 502 executes the program, it implements the aforementioned power battery thermal runaway warning method.

[0083] According to the vehicle-mounted electronic device of the present invention, by acquiring the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, and acquiring the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy, and performing thermal runaway warning for the power battery based on the heat generation per unit charge, the accuracy of thermal runaway warning can be effectively improved, and the reliability and cost are high.

[0084] Figure 6 This is a structural block diagram of an electric vehicle according to an embodiment of the present invention. (Reference) Figure 6 As shown, the electric vehicle 5000 includes the on-board electronic equipment 500 in the above embodiments.

[0085] According to the present invention, an electric vehicle can effectively improve the accuracy of thermal runaway warning by acquiring the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, and by acquiring the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy, and by providing thermal runaway warning for the power battery based on the heat generation per unit charge. This method is highly reliable and low in cost.

[0086] Figure 7 This is a structural block diagram of a thermal runaway early warning device for a power battery according to an embodiment of the present invention. (Reference) Figure 7As shown, the thermal runaway early warning device 600 for the power battery includes an acquisition module 601 and an alarm module 602. The acquisition module 601 acquires the accumulated charge of the power battery and the cooling energy used to cool the power battery within a preset time period, and acquires the heat generated per unit charge of the power battery based on the accumulated charge and cooling energy. The alarm module 602 provides a thermal runaway early warning for the power battery based on the heat generated per unit charge.

[0087] In one embodiment, the acquisition module 601 is specifically used to: acquire the voltage and current of the power battery; and calculate the accumulated power based on the voltage, current, and preset time.

[0088] Furthermore, the accumulated power includes the charging or discharging power of the power battery.

[0089] In one embodiment, the acquisition module 601 is specifically used to: acquire the coolant inlet temperature and coolant outlet temperature of the power battery; and calculate the cooling energy based on the coolant inlet temperature, coolant outlet temperature, and a preset time.

[0090] In one embodiment, the acquisition module 601 is specifically used to: acquire the ratio of cooling energy to accumulated charge to obtain the heat generated per unit charge of the power battery.

[0091] In one embodiment, the alarm module 602 is specifically used to: issue a thermal runaway warning if the heat generated per unit of electricity exceeds a preset threshold.

[0092] It should be noted that for the description of the thermal runaway early warning device for the power battery in this application, please refer to the description of the thermal runaway early warning method for the power battery in this application, and will not be repeated here.

[0093] According to an embodiment of the present invention, a thermal runaway early warning device for a power battery acquires the accumulated charge of the power battery and the cooling energy used to cool the power battery within a preset time by an acquisition module, and acquires the heat generated per unit charge of the power battery based on the accumulated charge and the cooling energy, and provides a thermal runaway early warning for the power battery based on the heat generated per unit charge by an alarm module. This effectively improves the accuracy of the thermal runaway early warning, and is highly reliable and low in cost.

[0094] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0095] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0096] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0097] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0098] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0099] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for early warning of thermal runaway in a power battery, characterized in that, The method includes: The cumulative charge of the power battery and the cooling energy used to cool the power battery are obtained within a preset time period. The heat generation per unit charge of the power battery is obtained based on the accumulated charge and the cooling energy, wherein obtaining the heat generation per unit charge of the power battery based on the accumulated charge and the cooling energy includes: obtaining the ratio of the cooling energy to the accumulated charge to obtain the heat generation per unit charge of the power battery; Thermal runaway warning is provided for the power battery based on the heat generated per unit of electricity. The step of obtaining the cumulative charge of the power battery within a preset time period includes: Obtain the voltage and current of the power battery; The accumulated power is calculated based on the voltage, the current, and the preset time, wherein the accumulated power includes the charging power or discharging power of the power battery; The cooling energy generated by the battery cooling system is used to offset the heat generated by the power battery.

2. The thermal runaway early warning method for power batteries according to claim 1, characterized in that, Obtaining the cooling energy used for cooling the power battery within a preset time period includes: Obtain the coolant inlet temperature and coolant outlet temperature of the power battery; The cooling energy is calculated based on the coolant inlet temperature, the coolant outlet temperature, and the preset time.

3. The method for early warning of thermal runaway of a power battery according to any one of claims 1-2, characterized in that, The method of providing thermal runaway warning for the power battery based on the heat generated per unit of electricity includes: If the heat generated per unit of electricity exceeds a preset threshold, a thermal runaway warning will be issued.

4. A vehicle-mounted electronic device, characterized in that, include: A memory, a processor, and a thermal runaway early warning program for a power battery stored in the memory and executable on the processor, wherein when the processor executes the program, it implements a thermal runaway early warning method for a power battery according to any one of claims 1-3.

5. An electric vehicle, characterized in that, Including the vehicle-mounted electronic equipment as described in claim 4.

6. A thermal runaway early warning device for a power battery, characterized in that, The apparatus for implementing the thermal runaway early warning method for a power battery according to any one of claims 1-3 includes: An acquisition module is used to acquire the cumulative charge of the power battery and the cooling energy used to cool the power battery within a preset time, and to acquire the heat generation per unit charge of the power battery based on the cumulative charge and the cooling energy. Specifically, the acquisition module is used to: acquire the ratio of the cooling energy to the cumulative charge to obtain the heat generation per unit charge of the power battery. An alarm module is used to provide early warning of thermal runaway of the power battery based on the heat generated per unit of electricity.

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