New energy automobile power storage battery over-temperature and over-charge risk grading and handling method

Abstract

The invention relates to the field of storage battery risk disposal, in particular to a new energy automobile power storage battery over-temperature and over-charge risk grading and disposal method. According to the method, accumulated high temperature risk and accumulated overcharge risk indexes are designed for power storage battery over-temperature and over-charge risks to guide accumulated risk grading management and control, different grades of alarm and management and control measures are set according to accumulated risk degrees, major hidden dangers caused by alarm disappearance due to excitation of disappearance of an external source can be fundamentally solved, and the safety of the power storage battery is improved. The safety and the reliability of the power storage battery are improved, and the sudden vehicle fire frequency is reduced; the vehicle control unit has the functions of recording the high-temperature alarm occurrence frequency, the high-temperature battery box body position number, the accumulated overcharge amount, the overcharge single box body position number and the like, accumulated risks can be effectively controlled, abnormity can be found in time, corresponding measures are taken, and the safety of the power storage battery is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of risk disposal of storage batteries, and particularly to a method for grading and disposing of over-temperature and over-charging risks of power storage batteries for new energy vehicles. Background Art

[0002] In recent years, with the rapid development of new energy vehicles, the safety and reliability issues of power storage batteries have received increasing attention. During the use of power storage batteries, faults such as over-temperature or over-charging may occur, which will not only shorten the service life of the batteries, but also may trigger serious safety accidents such as fire and explosion, posing threats to vehicle and personal safety.

[0003] In the prior art, there is a lack of effective cumulative risk grading and control measures for the over-temperature and over-charging risks of power storage batteries. Generally, the method adopted is that when the battery temperature or voltage is detected to exceed the preset threshold, a 1-3 level alarm signal is issued according to the temperature or voltage value, and countermeasures such as cutting off charging or limiting power are taken. However, once the charging stops, the voltage or temperature will drop, and the corresponding alarm will disappear. The alarm and control measures in this way are relatively single, unable to effectively distinguish the cumulative risks in different degrees and different times, and it is difficult to take accurate alarm and control measures according to the corresponding risk levels. In particular, it leaves a major safety hazard that the over-voltage and over-temperature alarms that occur at night for the vehicle automatically disappear and no one knows, and it is also one of the main reasons behind the sudden fire of the vehicle. And the prior art lacks functions such as recording the number of occurrences of high-temperature alarms of the battery, the position number of the high-temperature battery box, the cumulative over-charging amount, and the position number of the over-charged single-cell box, etc., and cannot effectively control the cumulative risks, bringing great safety hazards to the vehicle.

[0004] Based on the above background, a method for grading and disposing of over-temperature and over-charging risks of power storage batteries for new energy vehicles is thus proposed to solve the problems raised. Summary of the Invention

[0005] Other features and advantages of the present invention will be described in the following specification, and will become partially obvious from the specification, or be understood by implementing the present invention.

[0006] The purpose of the present invention is to overcome the above deficiencies and provide a method for grading and disposing of over-temperature and over-charging risks of power storage batteries for new energy vehicles.

[0007] To achieve the above purpose, the technical solution of the present invention is: A method for grading and disposing of over-temperature risks of power storage batteries for new energy vehicles, comprising: The over-temperature risk grading is at least divided into two levels, namely the first temperature gradient and the second temperature gradient, and the second temperature gradient is greater than the first temperature gradient; When the highest temperature of the power battery exceeds the first temperature level, the instrument on the vehicle gives a corresponding alarm response; When the highest temperature of the power battery exceeds the second temperature level, the controller on the vehicle issues a command for the vehicle to stop, and sends a rescue request message to the enterprise platform; The vehicle has the function of recording the number of occurrences of high-temperature alarm responses and the function of recording the corresponding box position number of the power battery with high temperature; When the cumulative high-temperature risk times of the power battery exceed 10, the instrument on the vehicle gives a corresponding alarm response, sends a battery severe over-temperature alarm signal to the enterprise platform, and the controller on the vehicle issues a torque and speed limit command, and the vehicle can only travel slowly at a low speed.

[0008] In some embodiments, the first temperature level and the second temperature level are 60 °C and 65 °C respectively.

[0009] In some embodiments, the alarm response issued when exceeding the first temperature level is that the corresponding yellow indicator light on the instrument lights up, and at the same time, a text prompt indicates that the battery is over-temperature.

[0010] In some embodiments, the vehicle has the function of calculating the high-temperature high-risk value of the power battery, and its calculation basis formula is as follows:

[0011] In the formula: Tmax represents the highest temperature (°C) on the day of the i-th high-temperature alarm; HT(i) represents the high-temperature risk value on the day of the high-temperature alarm.

[0012] In some embodiments, the vehicle has the function of calculating the cumulative number of occurrences of high-temperature alarm high risks of the power battery, and its calculation basis formula is as follows:

[0013] In the formula: Riskht represents the cumulative high-temperature risk of N high-temperature alarms ( / ); N represents the cumulative number of related alarms (times); HT(i) represents the high-temperature risk value on the day of the high-temperature alarm.

[0014] A method for classifying and disposing overcharge risks of a power battery of a new energy vehicle, including: The overcharge risk classification is at least divided into two levels, namely the first threshold level and the second threshold level, where the threshold is represented by the highest single-cell voltage of the power battery or the percentage of the power battery charge reaching the rated capacity, and the second threshold level is greater than the first threshold level; When the highest single - cell voltage of the power battery or the percentage of the charge amount reaching the rated capacity exceeds the first threshold level, the instrument on the vehicle gives an alarm by turning on the corresponding indicator light. When the highest single - cell voltage of the power battery or the percentage of the charge amount reaching the rated capacity exceeds the second threshold level, the instrument on the vehicle gives an alarm by turning on the corresponding indicator light and sends a battery serious over - charge alarm signal to the enterprise platform. The vehicle has the functions of recording the over - charge amount of the power battery single cell, calculating the cumulative number of over - charge amount calculation times, and recording the position number of the corresponding box of the over - charged power battery. When the cumulative value of the over - charge amount of the power battery reaches more than 5%, the instrument on the vehicle gives an alarm by turning on the corresponding indicator light. When the cumulative value of the over - charge amount of the power battery reaches more than 10%, the instrument on the vehicle gives an alarm by turning on the corresponding indicator light, and the controller on the vehicle issues a torque and speed limit instruction, and the vehicle can only move slowly at a low speed.

[0015] In some embodiments, the first threshold level is 50 mV when representing the highest single - cell voltage of the power battery, and 2% when representing the percentage of the charge amount reaching the rated capacity; the second threshold level is 100 mV when representing the highest single - cell voltage of the power battery, and 5% when representing the percentage of the charge amount reaching the rated capacity.

[0016] In some embodiments, the alarm measure when exceeding the first threshold level is that the corresponding yellow indicator light on the instrument lights up, and at the same time, there is a text prompt of battery over - charge; the alarm measure when exceeding the second threshold level is that the corresponding red indicator light on the instrument lights up, and at the same time, there is a text prompt of serious battery over - charge.

[0017] In some embodiments, the vehicle has the function of calculating the over - charge amount of the power battery, and its calculation basis formula is as follows:

[0018] In the formula: I represents the over - charge process current (A); Qoc(i) represents the total over - charge amount (Ah) of the i - th over - charge process; t1 represents the over - charge start time (s); t2 represents the over - charge end time (s).

[0019] In some embodiments, the vehicle has the function of calculating the cumulative number of over - charge amount occurrences of the power battery, and its calculation basis formula is as follows:

[0020] Where: Qoc(i) represents the total overcharge amount (Ah) during the i-th overcharge process; Qn represents the rated capacity (Ah) of the battery system; ACoc represents the cumulative value of N overcharges, with the unit of percentage (%); N represents the cumulative number of related alarms (times).

[0021] By adopting the above technical solutions, the beneficial effects of the present invention are as follows: 1. Aiming at the risks of overheating and overcharging of power batteries, the present invention adopts cumulative risk value hierarchical control measures, sets different levels of alarms and control measures according to the cumulative risk degree, can fundamentally solve the major hidden dangers caused by the disappearance of the excitation external source leading to the disappearance of the alarm, improve the safety and reliability of power batteries, effectively avoid serious accidents, and reduce the frequency of sudden vehicle fires; 2. The vehicle controller has functions such as recording the number of high-temperature alarm occurrences, the position number of the high-temperature battery box, the cumulative overcharge amount, and the position number of the overcharged single battery box, etc., can effectively control the cumulative risk, and timely discover abnormalities and take corresponding measures; 3. The alarms and control measures for overheating and overcharging are diversified, can distinguish risks of different degrees, and adopt targeted hierarchical control measures, improving the safety and reliability of power batteries; 4. The present invention requires extremely low computing power for the hierarchical control of power batteries, the method is simple and easy to implement, and has the feasibility of realizing engineering applications at the vehicle end.

[0022] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. Specific Embodiments

[0025] The following will combine embodiments to detail the implementation manners of the present invention, so as to fully understand how the present invention uses technical means to solve technical problems and achieve the realization process of technical effects and implement accordingly. It should be noted that as long as there is no conflict, each embodiment in the present invention and each feature in each embodiment can be combined with each other, and the formed technical solutions are all within the protection scope of the present invention.

[0026] Meanwhile, in the following description, for the purpose of explanation, many specific details are elaborated to provide a thorough understanding of the embodiments of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without these specific details or in the specific manners described herein.

[0027] The present invention provides a method for grading and disposing of over-temperature risks of power batteries for new energy vehicles, including: the over-temperature risk grading is at least divided into two levels, namely the first temperature level and the second temperature level, and the second temperature level is higher than the first temperature level; when the highest temperature of the power battery exceeds the first temperature level, the instrument on the vehicle issues a corresponding alarm for disposal; when the highest temperature of the power battery exceeds the second temperature level, the controller on the vehicle issues an instruction for the vehicle to stop, and sends a request for rescue information to the enterprise platform; the vehicle has the function of recording the number of occurrences of high-temperature alarm disposal and the function of recording the position number of the corresponding box of the power battery with high temperature; when the cumulative number of high-temperature risk times of the power battery exceeds 10, the instrument on the vehicle issues a corresponding alarm for disposal, and sends a battery serious over-temperature alarm signal to the enterprise platform, and the controller on the vehicle issues a torque and speed limit instruction, and the vehicle can only travel slowly at a low speed.

[0028] By adopting the above technical solutions, when monitoring the temperature of the power battery, if the temperature is lower than the first temperature level, the vehicle runs normally. When the highest temperature exceeds the first temperature level, the instrument on the vehicle will alarm and display, and at the same time, a text prompt will indicate that the battery is over-temperature; when the highest temperature exceeds the second temperature level, the vehicle controller will issue a stop instruction, the vehicle should stop, and send a request for rescue information to the enterprise platform, waiting for rescue. It is not until the over-temperature problem of the power battery of the vehicle is rectified and the highest temperature of the power battery drops to normal temperature that the stop function can be released.

[0029] When the cumulative number of high-temperature risk times of the power battery exceeds a certain number, the red warning light of the power battery failure on the instrument of the vehicle alarms, and at the same time, a text prompt indicates that the battery is seriously over-temperature, and charging should be stopped, and a battery serious over-temperature alarm signal is sent to the enterprise platform. The vehicle controller issues a torque and speed limit instruction, and the vehicle can only travel slowly at a maximum speed of 30 km / h, and the drive power limit warning light (yellow) lights up until the vehicle temperature returns to normal and the high-temperature problem is rectified, and then the alarm signal and the limit function can be released.

[0030] According to some embodiments of the present application, optionally, the first temperature level and the second temperature level are 60°C and 65°C respectively. This temperature level is the most suitable high-temperature boundary for the power battery, because when the power battery exceeds 60°C, the cathode material of the battery will decompose, especially for lithium iron phosphate batteries and ternary lithium batteries, which will cause material structure changes and lattice damage, further affecting the performance of the battery. Exceeding 65°C belongs to an abnormal situation of the power battery, which will cause a series of problems, affect the charging capacity of the battery, increase the internal impedance, reduce the migration speed of lithium ions, and ultimately lead to battery failure. According to some embodiments of the present application, optionally, the alarm disposal issued when exceeding the first temperature level is that the corresponding yellow indicator light on the instrument lights up, and at the same time, a text prompt indicates that the battery is over-temperature. It has a good role in prompting the driver in many aspects.

[0031] According to some embodiments of the present application, optionally, the vehicle is equipped with a function of calculating the high-temperature high-risk value of the power battery, and the calculation basis formula is as follows:

[0032] In the formula: Tmax represents the highest temperature (°C) on the day of the i-th high-temperature alarm; HT(i) represents the high-temperature risk value on the day of the high-temperature alarm.

[0033] The vehicle is equipped with a function of calculating the cumulative number of high-risk occurrences of high-temperature alarms of the power battery, and the calculation basis formula is as follows:

[0034] In the formula: Riskht represents the cumulative high-temperature risk of N high-temperature alarms ( / ); N represents the cumulative number of relevant alarms (times); HT(i) represents the high-temperature risk value on the day of the high-temperature alarm.

[0035] It can be known from the above formula that the values greater than the first temperature gradient or the second temperature gradient can be calculated. When the cumulative high-temperature risk of the power battery exceeds 10, corresponding alarm and torque and rotation speed limit disposal are made, so as to distinguish risks of different levels and take targeted hierarchical control measures.

[0036] According to some embodiments of the present application, optionally, the above strategy can be applied to the vehicle control unit (VCU) of the whole vehicle, or can also be applied to the battery management system (BMS).

[0037] A method for grading and disposing of overcharge risks of power batteries for new energy vehicles, comprising: the overcharge risk grading is at least divided into two levels, namely the first threshold level and the second threshold level, where the threshold is represented by the highest single-cell voltage of the power battery or the percentage of the power battery charge reaching the rated capacity, and the second threshold level is greater than the first threshold level; when the highest single-cell voltage of the power battery or the percentage of the charge reaching the rated capacity exceeds the first threshold level, the instrument on the vehicle gives an alarm by corresponding indicator lights; when the highest single-cell voltage of the power battery or the percentage of the charge reaching the rated capacity exceeds the second threshold level, the instrument on the vehicle gives an alarm by corresponding indicator lights and sends a battery serious overcharge alarm signal to the enterprise platform; the vehicle has the functions of recording the overcharged power of the single cell of the power battery, calculating the cumulative number of overcharge times, and recording the position number of the corresponding box of the overcharged power battery; when the cumulative value of the overcharged power of the power battery reaches more than 5%, the instrument on the vehicle gives an alarm by corresponding indicator lights; when the cumulative value of the overcharged power of the power battery reaches more than 10%, the instrument on the vehicle gives an alarm by corresponding indicator lights, and the controller on the vehicle issues a torque and speed limit command, and the vehicle can only travel slowly at a low speed. Among them, when the first threshold level represents the highest single-cell voltage of the power battery, it is 50 mV, and when it represents the percentage of the charge reaching the rated capacity, it is 2%, and when the second threshold level represents the highest single-cell voltage of the power battery, it is 100 mV, and when it represents the percentage of the charge reaching the rated capacity, it is 5%.

[0038] By adopting the above technical solutions, when the highest single-cell voltage of the power battery exceeds the threshold by more than 50 mV or the overcharged power reaches more than 2% of the rated capacity, the vehicle should give an audible and visual alarm; when the highest single-cell voltage of the power battery exceeds the threshold by more than 100 mV or the overcharged power reaches more than 5% of the rated capacity, the vehicle should give an audible and visual alarm, the instrument on the vehicle alarms with the red indicator light of the power battery failure, and at the same time gives a text prompt that the battery is seriously overcharged, and the charging circuit should be cut off as soon as possible or the braking energy recovery function should be turned off, and a battery serious overcharge alarm signal should be sent to the enterprise platform.

[0039] When the cumulative number of overcharge risks of the power battery reaches more than 5%, the red signal light of the power battery failure on the car's instrument panel will alarm, and the text will prompt that the battery is seriously overcharged. The charging circuit should be cut off or the brake recovery function should be turned off as soon as possible, and the battery serious overcharge alarm signal will be sent to the enterprise platform. The alarm signal can only be lifted until the vehicle stops charging or recharging and the voltage returns to normal; when the cumulative number of overcharge risks of the power battery reaches more than 10%, the red signal light of the power battery failure on the car's instrument panel will always be on, and the vehicle controller will issue a torque limit command. The vehicle can only limp at a maximum speed of 30 km / h, and the yellow signal light of the drive power limit will alarm, and the vehicle SOC must be less than 90% at the next charge. After the vehicle overcharge problem is rectified, the vehicle records the replacement of the overcharged battery box, and the vehicle records the cumulative overcharge of the box number. After that, the alarm signals of various functions can be lifted.

[0040] According to some embodiments of the present application, optionally, when the first threshold level is exceeded, the alarm treatment issued is that the corresponding yellow indicator light on the instrument lights up, and the text prompts that the battery is overcharged; when the second threshold level is exceeded, the alarm treatment issued is that the corresponding red indicator light on the instrument lights up, and the text prompts that the battery is seriously overcharged. It has the function of better reminding the driver in many aspects.

[0041] According to some embodiments of the present application, optionally, the vehicle has a function of calculating the overcharge amount of the power battery, and the calculation is based on the following formula:

[0042] Where: I represents the overcharge process current (A); Qoc(i) represents the total overcharge amount of the i-th overcharge process (Ah); t1 represents the overcharge start time (s); t2 represents the overcharge end time (s).

[0043] The car has the function of calculating the cumulative number of overcharges of the power battery, and the calculation is based on the following formula:

[0044] Where: Qoc(i) represents the total overcharge capacity of the i-th overcharge process (Ah); Qn represents the rated capacity of the battery system (Ah); ACoc represents the cumulative value of N overcharges, in percentage (%); N represents the cumulative number of related alarms (times).

[0045] From the above formula, it can be seen that a value greater than the first threshold level or the second threshold level can be calculated. When the cumulative number of power battery overcharging risks reaches the set value, corresponding alarms and torque and limit torque measures are made to distinguish different degrees of risks and take targeted graded control measures.

[0046] According to some embodiments of the present application, optionally, the above strategy can be applied to the vehicle control unit (VCU) of the whole vehicle, or can also be applied to the battery management system (BMS).

[0047] It should be understood that the embodiments disclosed in the present invention are not limited to the specific processing steps or materials disclosed herein, but should extend to equivalent alternatives of such features understood by those of ordinary skill in the relevant art. It should also be understood that the terms used herein are for the purpose of describing specific embodiments only and do not imply limitation.

[0048] The "embodiments" mentioned in the specification mean that the specific features or characteristics described in connection with the embodiments are included in at least one embodiment of the present invention. Therefore, the phrase "embodiments" that appears throughout the specification does not necessarily refer to the same embodiment.

[0049] In addition, the described features or characteristics can be combined in any other suitable manner into one or more embodiments. In the above description, some specific details, such as thickness, quantity, etc., are provided to provide a comprehensive understanding of the embodiments of the present invention. However, those skilled in the relevant art will understand that the present invention can be implemented without one or more of the above specific details or can also be implemented using other methods, components, materials, etc.

Claims

1. A new energy vehicle power battery overtemperature risk classification and treatment method, characterized in that: include: The over-temperature risk classification is divided into at least two levels, namely the first temperature level and the second temperature level, and the second temperature level is greater than the first temperature level; When the maximum temperature of the power battery exceeds the first temperature level, the instrument on the vehicle issues a corresponding alarm; When the maximum temperature of the power battery exceeds the second temperature level, the controller on the vehicle issues a command to stop the vehicle and sends a rescue request message to the enterprise platform; The vehicle has a function of recording the number of high temperature alarms and the corresponding box position number of the power battery at high temperature; When the cumulative number of high temperature risks of the power battery exceeds 10, the instrument on the vehicle will issue a corresponding alarm and send a battery severe overtemperature alarm signal to the enterprise platform, and the controller on the vehicle will issue a torque limit instruction, so the vehicle can only travel at a low speed.

2. A new energy vehicle power battery overtemperature risk classification and treatment method according to claim 1, characterized in that: The first temperature step and the second temperature step are 60° C. and 65° C. respectively.

3. A new energy vehicle power battery overtemperature risk classification and treatment method according to claim 1, characterized in that: The alarm response when the first temperature level is exceeded is that the corresponding yellow indicator light on the instrument lights up, and a text prompt indicates that the battery is over-temperature.

4. A new energy vehicle power battery overtemperature risk classification and treatment method according to claim 1, characterized in that: The automobile has the function of calculating the high-temperature high-risk value of the power battery, and the calculation is based on the following formula: ， Where: Tmax represents the maximum temperature on the day of the i-th high temperature alarm (°C); HT(i) represents the high temperature risk value on the day of the high temperature alarm.

5. A new energy vehicle power battery overtemperature risk classification and treatment method according to claim 4, characterized in that: The automobile has a function of calculating the cumulative high temperature risk of the power battery high temperature alarm, and the calculation is based on the following formula: ， Where: Riskht represents the cumulative high temperature risk of N high temperature alarms ( / ); N represents the cumulative number of related alarms (times); HT(i) represents the high temperature risk value on the day of the high temperature alarm.

6. A method for grading and handling overcharge risks of power batteries for new energy vehicles, characterized in that: include: The overcharge risk classification is divided into at least two levels, namely the first threshold level and the second threshold level, wherein the threshold is expressed as the highest single cell voltage of the power battery or the percentage of the power battery charge amount to the rated capacity, and the second threshold level is greater than the first threshold level; When the highest cell voltage of the power storage battery or the percentage of the charge capacity to the rated capacity exceeds the first threshold level, the instrument on the vehicle emits a corresponding indicator light to carry out an alarm; When the highest single cell voltage or the percentage of the charged capacity of the power battery to the rated capacity exceeds the second threshold level, the instrument on the vehicle emits a corresponding indicator light for alarm processing, and sends a battery serious overcharge alarm signal to the enterprise platform; The vehicle has the function of recording the overcharged power of the power battery cells, calculating the cumulative number of overcharges, and recording the corresponding box position number of the overcharged power battery; When the accumulated value of the overcharge of the power battery reaches 5% or more, the instrument on the vehicle emits a corresponding indicator light to give an alarm; When the accumulated value of overcharge of the power battery reaches 10% or more, the instrument on the vehicle emits a corresponding indicator light for alarm processing, and the controller on the vehicle issues a torque limit instruction, so that the vehicle can only travel slowly at a low speed.

7. A new energy vehicle power battery overcharge risk classification and disposal method according to claim 1, characterized in that: The first threshold level indicates that the maximum single cell voltage of the power battery is 50mV, indicating that the percentage of the charged capacity to the rated capacity is 2%. The second threshold level indicates that the maximum single cell voltage of the power battery is 100mV, indicating that the percentage of the charged capacity to the rated capacity is 5%.

8. A new energy vehicle power battery overcharge risk classification and disposal method according to claim 1, characterized in that: When the first threshold level is exceeded, the alarm response is that the corresponding yellow indicator light on the instrument lights up, and a text prompt is displayed indicating that the battery is overcharged; when the second threshold level is exceeded, the alarm response is that the corresponding red indicator light on the instrument lights up, and a text prompt is displayed indicating that the battery is severely overcharged.

9. A new energy vehicle power battery overcharge risk classification and disposal method according to claim 1, characterized in that: The vehicle has the function of calculating the overcharge amount of the power battery, and the calculation is based on the following formula: ， Where: I represents the overcharge process current (A); Qoc(i) represents the total overcharge amount of the i-th overcharge process (Ah); t1 represents the overcharge start time (s); t2 represents the overcharge end time (s).

10. A new energy vehicle power battery overcharge risk classification and disposal method according to claim 9, characterized in that: The vehicle has a function of calculating the number of times the power battery is cumulatively overcharged, and the calculation is based on the following formula: ， Where: Qoc(i) represents the total overcharge capacity of the i-th overcharge process (Ah); Qn represents the rated capacity of the battery system (Ah); ACoc represents the cumulative value of N overcharges, in percentage (%); N represents the cumulative number of related alarms (times).

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