New energy automobile power battery power supply detection method

Abstract

The invention discloses a new energy automobile power battery power supply detection method, and relates to the technical field of battery power supply detection, and the method comprises the following steps: S1, transmitting sound waves through an ultrasonic transceiver attached to the surface of a new energy automobile power battery; s2, collecting the real-time density of an electrolyte in the power battery, calculating a plurality of dynamic ratios of the power battery, and generating an internal mobility; and S3, determining whether the power supply state of the power battery is normal or not according to the transmitted sound waves of the ultrasonic transceiver and the internal mobility. According to the invention, multidirectional guidance is provided for power supply detection of the battery, the accuracy of judging whether the power battery swells or not is improved, and the safety problem caused by battery swelling is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of battery power supply detection, and in particular to a method for detecting power supply of a power battery of a new energy vehicle. Background Art

[0002] With the increasing global awareness of environmental protection and the transformation of energy structure, the new energy vehicle industry has developed rapidly. One of the core components of new energy vehicles is its power battery, which directly determines the vehicle's endurance, safety and service life. The performance status of the power battery, especially the integrity and health of its internal structure, is crucial to ensure the normal operation of the vehicle.

[0003] During long-term use, power batteries may experience internal structural changes due to factors such as charge and discharge cycles, temperature changes, and material aging, such as uneven electrolyte density distribution, active material shedding, and plate expansion. The most direct and serious manifestation is battery bulging. Battery bulging not only affects the sealing of the battery package, causing electrolyte leakage, but may also cause internal short circuits, resulting in thermal runaway or even explosions and other safety hazards.

[0004] Traditional power battery detection methods mostly rely on monitoring external parameters such as voltage, current and temperature, but these methods are often difficult to directly reflect the changes in the microstructure and physical and chemical state of the battery, and lack the ability to warn of early bulging. Therefore, it is particularly important to develop a technology that can non-destructively and in real time monitor the internal state of power batteries, especially to accurately identify battery bulging. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a new energy vehicle power battery power supply detection method.

[0006] The technical solution of the present invention is: a new energy vehicle power battery power supply detection method comprises the following steps:

[0007] S1. Using an ultrasonic transceiver attached to the surface of the power battery of a new energy vehicle to emit sound waves;

[0008] S2. Collect the real-time density of the electrolyte inside the power battery, calculate several dynamic ratios of the power battery, and generate the internal mobility;

[0009] S3. Determine whether the power supply status of the power battery is normal based on the transmitted sound waves of the ultrasonic transceiver and the internal mobility.

[0010] As a non-destructive testing technology, ultrasonic testing technology can reflect the internal structural information of materials due to its advantages such as sensitivity to internal defects of materials, high detection efficiency and simple operation. Ultrasonic testing technology is applied to the status monitoring of power batteries for new energy vehicles, especially in combination with the unique electrochemical characteristics of power batteries (such as changes in electrolyte density), to achieve early detection and accurate evaluation of internal abnormalities such as battery bulging.

[0011] Furthermore, S2 includes the following sub-steps:

[0012] S21, collecting the density of the electrolyte inside the power battery at each time, and calculating the flow field distribution of the power battery at each time;

[0013] S22. Calculate the dynamic ratio of the power battery at each moment according to the size of the power battery and the flow field distribution at each moment;

[0014] S23. Generate an internal mobility for the power battery according to the dynamic ratio of the power battery at all times.

[0015] The beneficial effect of the above further scheme is that in the present invention, by collecting the density of the electrolyte inside the power battery in real time, the internal state of the battery can be monitored in real time, and the change of the electrolyte density can be captured in time, thereby reflecting the performance of the battery. The calculation of the flow field distribution takes into account the flow of the electrolyte at each moment, providing a comprehensive view of the dynamic changes inside the battery; and the calculation of the dynamic ratio takes into account the change of the flow field distribution, which can more accurately evaluate the performance state of the battery at different moments, providing a more accurate basis for battery monitoring.

[0016] Furthermore, in S21, the power battery The flow field distribution at time The calculation formula is:

[0017] ;

[0018] In the formula, Indicates that the electrolyte The density of time, represents the initial density of the electrolyte, represents a constant, Indicates the porosity of the positive electrode sheet, Indicates The length of the positive electrode, Indicates The width of the positive electrode, Indicates The height of the positive electrode is Indicates the number of positive plates, Indicates The porosity of the negative electrode sheet is Indicates The length of the negative electrode, Indicates The width of the negative electrode, Indicates The height of the negative electrode is Indicates the number of negative plates, represents the pore volume of the diaphragm.

[0019] Further, in S22, the power battery Dynamic ratio of time The calculation formula is:

[0020] ;

[0021] In the formula, Indicates the volume of the power battery. Indicates that the electrolyte The density of time, Indicates that the electrolyte The density of time, Indicates that the electrolyte The density of time, Indicates the power battery The flow field distribution at time .

[0022] Further, S23 includes the following sub-steps:

[0023] S231, arranging all dynamic ratios in chronological order to obtain a dynamic ratio sequence;

[0024] S232, extracting the LOF sequence of the dynamic ratio sequence;

[0025] S233. Generate internal mobility for the power battery according to the LOF sequence.

[0026] The beneficial effect of the above further scheme is that: in the present invention, LOF is a local anomaly factor of a data point, which represents the ratio of the local density of the point to the local density of its neighboring points. The LOF method does not need to assume that the data follows a specific distribution, so it is suitable for dynamic ratios with time series connection, and can detect dynamic ratios located in different density areas. The LOF sequence can be used to identify abnormal changes in the performance parameters of the power battery, thereby determining the parameters affecting the electrolyte on the battery power supply.

[0027] Furthermore, in S233, the internal mobility The calculation formula is:

[0028] ;

[0029] In the formula, Indicates the LOF sequence elements, Indicates the number of elements in the LOF sequence, Indicates the LOF sequence elements less than or equal to the set threshold, Indicates the number of elements in the LOF sequence that are less than or equal to the set threshold. Indicates generating a random number between 0 and 1.

[0030] Furthermore, S3 includes the following sub-steps:

[0031] S31, calculating the time difference between sending and receiving according to the transmitting time of the transmitted sound wave and the receiving time of the received sound wave;

[0032] S32, using the internal mobility to correct the time difference between sending and receiving to obtain the accurate time difference;

[0033] S33: When the precise time difference is less than the set time threshold, determine that the power supply condition of the power battery is abnormal.

[0034] The beneficial effect of the above further scheme is: in the present invention, the internal mobility reflects the parameters of the electrolyte inside the power battery. By using this parameter to correct the time difference between sending and receiving, the error caused by the change of the internal state of the battery can be compensated, and the accuracy of the time difference can be further improved, which can be applicable to power batteries in different states.

[0035] Furthermore, S32, precise time difference The calculation formula is:

[0036] ;

[0037] In the formula, represents the internal mobility, Indicates the time difference between sending and receiving.

[0038] The beneficial effects of the present invention are as follows: the present invention uses an ultrasonic transceiver to transmit sound waves, and there is no need to disassemble or destroy the power battery. It is a non-invasive detection method, which avoids possible damage to the battery during the disassembly process; at the same time, by collecting the real-time density of the electrolyte inside the power battery, the internal state of the battery can be accurately understood, and multiple dynamic ratios can be calculated and the internal mobility can be generated, which can fully reflect the performance changes of the power battery and correct the time difference between sending and receiving. The final time difference between sending and receiving combines the influence of the internal situation of the battery on the judgment of bulging, provides multi-faceted guidance for the power supply detection of the battery, improves the accuracy of judging whether the power battery is bulging, and avoids safety problems caused by battery bulging. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Flow chart of the power supply detection method for new energy vehicle power battery. DETAILED DESCRIPTION

[0040] The embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

[0041] like Figure 1 As shown, the present invention provides a new energy vehicle power battery power supply detection method, comprising the following steps:

[0042] S1. Using an ultrasonic transceiver attached to the surface of the power battery of a new energy vehicle to emit sound waves;

[0043] S2. Collect the real-time density of the electrolyte inside the power battery, calculate several dynamic ratios of the power battery, and generate the internal mobility;

[0044] S3. Determine whether the power supply status of the power battery is normal based on the transmitted sound waves of the ultrasonic transceiver and the internal mobility.

[0045] As a non-destructive testing technology, ultrasonic testing technology can reflect the internal structural information of materials due to its advantages such as sensitivity to internal defects of materials, high detection efficiency and simple operation. Ultrasonic testing technology is applied to the status monitoring of power batteries for new energy vehicles, especially in combination with the unique electrochemical characteristics of power batteries (such as changes in electrolyte density), to achieve early detection and accurate evaluation of internal abnormalities such as battery bulging.

[0046] In this embodiment of the present invention, S2 includes the following sub-steps:

[0047] S21, collecting the density of the electrolyte inside the power battery at each time, and calculating the flow field distribution of the power battery at each time;

[0048] S22. Calculate the dynamic ratio of the power battery at each moment according to the size of the power battery and the flow field distribution at each moment;

[0049] S23. Generate an internal mobility for the power battery according to the dynamic ratio of the power battery at all times.

[0050] In the present invention, by collecting the density of the electrolyte inside the power battery in real time, the internal state of the battery can be monitored in real time, and the change of the electrolyte density can be captured in time, thereby reflecting the performance of the battery. The calculation of the flow field distribution takes into account the flow of the electrolyte at each moment, providing a comprehensive view of the dynamic changes inside the battery; while the calculation of the dynamic ratio takes into account the change of the flow field distribution, which can more accurately evaluate the performance state of the battery at different moments, providing a more accurate basis for battery monitoring.

[0051] In the embodiment of the present invention, in S21, the power battery The flow field distribution at time The calculation formula is:

[0052] ;

[0053] In the formula, Indicates that the electrolyte The density of time, represents the initial density of the electrolyte, represents a constant, Indicates the porosity of the positive electrode sheet, Indicates The length of the positive electrode, Indicates The width of the positive electrode, Indicates The height of the positive electrode is Indicates the number of positive plates, Indicates The porosity of the negative electrode sheet is Indicates The length of the negative electrode, Indicates The width of the negative electrode, Indicates The height of the negative electrode is Indicates the number of negative plates, represents the pore volume of the diaphragm.

[0054] In the embodiment of the present invention, in S22, the power battery Dynamic ratio of time The calculation formula is:

[0055] ;

[0056] In the formula, Indicates the volume of the power battery. Indicates that the electrolyte The density of time, Indicates that the electrolyte The density of time, Indicates that the electrolyte The density of time, Indicates the power battery The flow field distribution at time .

[0057] In this embodiment of the present invention, S23 includes the following sub-steps:

[0058] S231, arranging all dynamic ratios in chronological order to obtain a dynamic ratio sequence;

[0059] S232, extracting the LOF sequence of the dynamic ratio sequence;

[0060] S233. Generate internal mobility for the power battery according to the LOF sequence.

[0061] In the present invention, LOF is a local anomaly factor of a data point, which represents the ratio of the local density of the point to the local density of its neighboring points. The LOF method does not need to assume that the data follows a specific distribution, so it is suitable for dynamic ratios with time series connection, and can detect dynamic ratios located in different density areas. The LOF sequence can be used to identify abnormal changes in power battery performance parameters, thereby determining the parameters affecting the electrolyte on battery power supply.

[0062] In the embodiment of the present invention, in S233, the internal mobility The calculation formula is:

[0063] ;

[0064] In the formula, Indicates the LOF sequence elements, Indicates the number of elements in the LOF sequence, Indicates the LOF sequence elements less than or equal to the set threshold, Indicates the number of elements in the LOF sequence that are less than or equal to the set threshold. Indicates generating a random number between 0 and 1.

[0065] In this embodiment of the present invention, S3 includes the following sub-steps:

[0066] S31, calculating the time difference between sending and receiving according to the transmitting time of the transmitted sound wave and the receiving time of the received sound wave;

[0067] S32, using the internal mobility to correct the time difference between sending and receiving to obtain the accurate time difference;

[0068] S33: When the precise time difference is less than the set time threshold, determine that the power supply condition of the power battery is abnormal.

[0069] In the present invention, the internal mobility reflects the parameters of the electrolyte inside the power battery. By using this parameter to correct the time difference between sending and receiving, the error caused by the change of the internal state of the battery can be compensated, the accuracy of the time difference can be further improved, and it can be applicable to power batteries in different states.

[0070] In the embodiment of the present invention, S32, precise time difference The calculation formula is:

[0071] ;

[0072] In the formula, represents the internal mobility, Indicates the time difference between sending and receiving.

[0073] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A new energy vehicle power battery power supply detection method, characterized in that: The following steps are involved: S1. Using an ultrasonic transceiver attached to the surface of the power battery of a new energy vehicle to emit sound waves; S2. Collect the real-time density of the electrolyte inside the power battery, calculate several dynamic ratios of the power battery, and generate the internal mobility; S3. Determine whether the power supply status of the power battery is normal based on the transmitted sound waves of the ultrasonic transceiver and the internal mobility.

2. The new energy vehicle power battery power supply detection method according to claim 1 is characterized in that: The S2 comprises the following sub-steps: S21, collecting the density of the electrolyte inside the power battery at each time, and calculating the flow field distribution of the power battery at each time; S22. Calculate the dynamic ratio of the power battery at each moment according to the size of the power battery and the flow field distribution at each moment; S23. Generate an internal mobility for the power battery according to the dynamic ratio of the power battery at all times.

3. The new energy vehicle power battery power supply detection method according to claim 2 is characterized in that: In S21, the power battery The flow field distribution at time The calculation formula is: ； In the formula, Indicates that the electrolyte The density of time, represents the initial density of the electrolyte, represents a constant, Indicates the porosity of the positive electrode sheet, Indicates The length of the positive electrode, Indicates The width of the positive electrode, Indicates The height of the positive electrode is Indicates the number of positive plates, Indicates The porosity of the negative electrode sheet is Indicates The length of the negative electrode, Indicates The width of the negative electrode, Indicates The height of the negative electrode is Indicates the number of negative plates, represents the pore volume of the diaphragm.

4. The new energy vehicle power battery power supply detection method according to claim 2 is characterized in that: In S22, the power battery Dynamic ratio of time The calculation formula is: ； In the formula, Indicates the volume of the power battery. Indicates that the electrolyte The density of time, Indicates that the electrolyte The density of time, Indicates that the electrolyte The density of time, Indicates the power battery The flow field distribution at time .

5. The new energy vehicle power battery power supply detection method according to claim 2 is characterized in that: The S23 comprises the following sub-steps: S231, arranging all dynamic ratios in chronological order to obtain a dynamic ratio sequence; S232, extracting the LOF sequence of the dynamic ratio sequence; S233. Generate internal mobility for the power battery according to the LOF sequence.

6. The new energy vehicle power battery power supply detection method according to claim 5 is characterized in that: In S233, the internal mobility The calculation formula is: ； In the formula, Indicates the LOF sequence elements, Indicates the number of elements in the LOF sequence, Indicates the LOF sequence elements less than or equal to the set threshold, Indicates the number of elements in the LOF sequence that are less than or equal to the set threshold. Indicates generating a random number between 0 and 1.

7. The new energy vehicle power battery power supply detection method according to claim 1 is characterized in that: The S3 comprises the following sub-steps: S31, calculating the time difference between sending and receiving according to the transmitting time of the transmitted sound wave and the receiving time of the received sound wave; S32, using the internal mobility to correct the time difference between sending and receiving to obtain the accurate time difference; S33: When the precise time difference is less than the set time threshold, determine that the power supply condition of the power battery is abnormal.

8. The new energy vehicle power battery power supply detection method according to claim 7 is characterized in that: The S32, precise time difference The calculation formula is: ； In the formula, represents the internal mobility, Indicates the time difference between sending and receiving.

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