An ultrasonic detection method, system and related device for battery slurry solid content

Abstract

The application relates to an ultrasonic detection method and system for battery slurry solid content and related equipment, and belongs to the technical field of ultrasonic detection. The method comprises the following steps: performing first ultrasonic detection on battery slurry to be detected in a transmission pipeline to obtain ultrasonic transmission information, and obtaining a predicted solid content according to the ultrasonic transmission information and a preset standard working curve; when the battery slurry to be detected is standard battery slurry with unknown solid content, the predicted solid content is directly used as an actual solid content; otherwise, whether a solid content calibration mechanism is triggered is judged according to the predicted solid content; if the judgment result is yes, a calibration parameter is obtained through the solid content calibration mechanism, and an actual solid content is obtained according to the calibration parameter and the predicted solid content; and a detection result is obtained according to the change of the actual solid content. The application effectively improves the large detection deviation problem of a traditional method for non-standard slurry, and significantly improves the detection precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of slurry solid content measurement, in particular to an ultrasonic detection method and system for battery slurry solid content and related equipment. BACKGROUND

[0002] In the manufacturing process of lithium ion batteries, the solid content (solid matter mass ratio) of the positive and negative electrode slurries of the battery is a core parameter that determines the quality of the electrode coating, the energy density and the cycle life of the battery. The traditional solid content detection mainly relies on the drying and weighing method after offline sampling, which has high accuracy, but has problems such as long detection period, inability to provide real-time feedback on production status, and high operation difficulty. With the increasing demand for process consistency and intelligent manufacturing in the power battery industry, online detection methods based on optics (such as near-infrared spectroscopy), microwaves or electrochemical impedance have been proposed, but these detection methods also have their own significant defects:

[0003] Optical methods use spectral characteristics to infer solid content, but spectral characteristics are easily disturbed by factors such as slurry color, particle distribution and environmental humidity during actual detection, resulting in inaccurate detection results; microwave methods use dielectric property differences to measure solid content, but this method is not suitable for negative electrode slurries with high conductive agent content, and is significantly affected by conductivity fluctuations; electrochemical impedance methods calculate solid content based on changes in slurry conductivity, but it is difficult to distinguish the contributions of multiple components (such as active materials, conductive agents and binders) in the slurry, and there is an unavoidable measurement error.

[0004] Therefore, in recent years, ultrasonic detection technology has become a potential solution due to its non-invasive, high penetration and real-time nature. The principle is to measure by analyzing the correlation between ultrasonic propagation characteristics (sound speed and attenuation coefficient) and solid content in the slurry, however, the current ultrasonic detection technology overcomes the defects of strong lag and sample destruction of traditional offline methods, but in the ultrasonic detection process, the ultrasonic propagation characteristics are easily affected by the coupling of multiple factors such as the solid content, agglomeration and bubbles of the battery slurry; existing detection models usually assume a monotonic linear relationship between ultrasonic transmission attenuation coefficient and solid content, but in actual working conditions, different factors (such as agglomeration and bubbles) can cause uneven distribution of ultrasonic transmission attenuation coefficient in the slurry, resulting in low accuracy of the solid content detection results. SUMMARY

[0005] To improve the problem of low accuracy of the above solid content detection results, the present application provides an ultrasonic detection method and system for battery slurry solid content and related equipment.

[0006] In a first aspect, the present application provides an ultrasonic detection method for battery slurry solid content, which adopts the following technical solution:

[0007] An ultrasonic detection method for battery slurry solid content, comprising:

[0008] performing first ultrasonic detection on the battery slurry to be detected in a transmission pipeline to obtain ultrasonic transmission information, and obtaining a predicted solid content according to the ultrasonic transmission information and a preset standard working curve;

[0009] when the battery slurry to be detected is a standard battery slurry with unknown solid content, directly taking the predicted solid content as the actual solid content;

[0010] otherwise, judging whether to trigger a solid content calibration mechanism according to the predicted solid content;

[0011] if yes, calibrating the predicted solid content through the solid content calibration mechanism to obtain the actual solid content;

[0012] obtaining a detection result according to the change of the actual solid content;

[0013] the solid content calibration mechanism comprises:

[0014] dividing the cross section of the ultrasonic detection part corresponding to the transmission pipeline into a plurality of detection regions;

[0015] performing third ultrasonic detection on the battery slurry to be detected to obtain a regional attenuation coefficient corresponding to each detection region;

[0016] generating a two-dimensional attenuation distribution matrix based on all the regional attenuation coefficients and the corresponding detection regions;

[0017] stacking the two-dimensional attenuation distribution matrices in the time dimension to form a three-dimensional attenuation distribution matrix according to the two-dimensional attenuation distribution matrices in a plurality of continuous second detection periods;

[0018] obtaining a calibration parameter based on the three-dimensional attenuation distribution matrix, the calibration parameter being used for fitting correction of the deviation of the predicted solid content.

[0019] By adopting the above technical solution, the present application directly obtains the solid content of the standard battery slurry by using the standard working curve, thereby ensuring the detection efficiency; and for non-standard battery slurry, the calibration mechanism is triggered, the deviation caused by possible local defects in the slurry is corrected through multi-dimensional attenuation field analysis, thereby greatly improving the accuracy of detecting the solid content of the slurry by ultrasonic technology;

[0020] In one specific implementation, the first ultrasonic detection is achieved by two transceiving probes symmetrically distributed along the circumference of the transmission pipeline by 180° in any one annular probe unit sleeved on the transmission pipeline, wherein one transceiving probe serves as a transmitting end to emit ultrasonic waves to the battery slurry to be detected, and the other transceiving probe serves as a receiving end to receive ultrasonic waves transmitted through the battery slurry to obtain ultrasonic transmission information.

[0021] In one specific implementation, the third ultrasonic detection is achieved by a plurality of transceiving probes uniformly distributed along the circumference of the transmission pipeline in at least one annular probe unit sleeved on the transmission pipeline, wherein one transceiving probe of every two transceiving probes among all the transceiving probes serves as a transmitting end to emit ultrasonic waves to the battery slurry to be detected, and the other transceiving probe serves as a receiving end to receive ultrasonic waves transmitted through the battery slurry, and an ultrasonic transmission path is formed between every two transceiving probes.

[0022] The third ultrasonic detection of the battery slurry to be detected includes:

[0023] According to a preset path rotation rule, the battery slurry to be detected is subjected to ultrasonic detection to obtain a received signal amplitude corresponding to each ultrasonic transmission path, and the path rotation rule is used to form different ultrasonic transmission paths by sequentially switching a combination of every two transceiving probes as a transmitting end or a receiving end.

[0024] According to all the received signal amplitudes, a regional attenuation coefficient corresponding to each detection region is obtained.

[0025] In one specific implementation, the ultrasonic detection of the battery slurry to be detected according to the preset path rotation rule to obtain a received signal amplitude corresponding to each ultrasonic transmission path specifically includes:

[0026] One transceiving probe is sequentially selected as a transmitting end, and a corresponding ultrasonic transceiving round is generated after the selection of each transmitting end, and in each ultrasonic transceiving round, each transceiving probe has only one opportunity to serve as a transmitting end.

[0027] After each ultrasonic transceiving round is obtained, one transceiving probe other than the current transmitting end is sequentially selected as a receiving end, and after the selection of each receiving end, a sub-round in the current ultrasonic transceiving round is generated.

[0028] In each sub-round, an ultrasonic transmission detection is performed based on an ultrasonic transmission path corresponding to the current transmitting end and the current receiving end to obtain a received signal amplitude corresponding to each ultrasonic transmission path.

[0029] In one specific implementation, each of the ultrasound transmission paths passes through one or more of the detection regions, and each of the ultrasound transmission paths corresponds to a region attenuation coefficient corresponding to each of the detection regions passed through; and the obtaining of the region attenuation coefficient corresponding to each of the detection regions according to all of the received signal amplitudes comprises:

[0030] determining a target function formula corresponding to each of the ultrasound transmission paths to obtain a plurality of linear equations, the target function formula being used to reflect a quantitative relationship between a preset transmitted signal amplitude, the received signal amplitude and all of the region attenuation coefficients corresponding thereto in the ultrasound transmission path, and each of the linear equations comprising one or more of the region attenuation coefficients;

[0031] determining an effective transmission path according to a ratio of each of the received signal amplitudes to the transmitted signal amplitude, the effective transmission path referring to an ultrasound transmission path corresponding to a ratio of the received signal amplitude to the transmitted signal amplitude within a preset ratio range;

[0032] substituting the received signal amplitude corresponding to each of the effective transmission paths and the preset transmitted signal amplitude into the corresponding linear equation to obtain a multivariate equation set composed of all of the linear equations;

[0033] calculating the region attenuation coefficient corresponding to each of the detection regions according to the multivariate equation set.

[0034] In one specific implementation, in each of the ultrasound transmission paths, an attenuation law of an ultrasonic transmission signal satisfies the target function formula, and the target function formula is an ultrasonic attenuation equation as follows:

[0035] ;

[0036] wherein, is a transmitted signal amplitude, and is a preset value; is the received signal amplitude; is a set of the detection regions corresponding to the kth ultrasound transmission path, is a region attenuation coefficient corresponding to the detection region (i, j), is a propagation distance of the ultrasonic transmission signal within the detection region (i, j).

[0037] In one specific implementation, the calculating of the region attenuation coefficient corresponding to each of the detection regions according to the multivariate equation set comprises:

[0038] obtaining a corresponding path-region propagation matrix according to the multivariate equation set, the path-region propagation matrix being in a matrix form of the multivariate equation set;

[0039] When the effective transmission paths satisfy preset direct solving conditions, the multi-equation system is solved by a least square method to obtain a region attenuation coefficient corresponding to each detection region, wherein the direct solving conditions include a minimum path number condition and a path distribution condition;

[0040] When the effective transmission paths do not satisfy the direct solving conditions, the multi-equation system is solved by an iterative regularization method to obtain a region attenuation coefficient corresponding to each detection region.

[0041] In one specific implementation, the determining whether to trigger the solid content calibration mechanism according to the predicted solid content includes:

[0042] The second ultrasonic detection is performed on the battery slurry to be detected, wherein the second ultrasonic detection corresponds to a plurality of annular probe units arranged at intervals along the transmission direction of the transmission pipeline, and the second ultrasonic detection is implemented by two transceiving probes symmetrically distributed at 180° along the circumferential direction of the transmission pipeline in different annular probe units in different first detection periods in succession, wherein one transceiving probe serves as a transmitting end to transmit ultrasonic waves to the battery slurry to be detected, and the other transceiving probe serves as a receiving end to receive ultrasonic waves transmitted through the battery slurry, one first detection period corresponds to one detection subunit, and ultrasonic transmission information corresponding to each detection subunit is obtained.

[0043] An ultrasonic transmission attenuation coefficient corresponding to each detection subunit is obtained according to the ultrasonic transmission information corresponding to each detection subunit.

[0044] A plurality of comparative solid contents of the battery slurry to be detected are obtained according to all the ultrasonic transmission attenuation coefficients and the standard working curve.

[0045] It is determined whether to trigger the solid content calibration mechanism according to the plurality of comparative solid contents of the battery slurry to be detected.

[0046] In a second aspect, the application provides an ultrasonic detection processing device, which adopts the following technical solution:

[0047] An ultrasonic detection processing device, characterized by comprising a memory and a processor, the memory stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to realize the ultrasonic detection method of the battery slurry solid content according to the first aspect.

[0048] In a third aspect, the application provides a computer readable storage medium, which adopts the following technical solution:

[0049] A computer-readable storage medium, the readable storage medium storing at least one instruction, at least one program, a code set or an instruction set, the at least one instruction, at least one program, code set or instruction set loaded and executed by a processor to implement the method for ultrasonic detection of battery slurry solid content according to the first aspect.

[0050] In summary, the present application includes at least one of the following beneficial technical effects:

[0051] 1. Unlike the conventional ultrasonic detection method which needs to consider additional interference factors such as bubbles, the present application directly inverts the regional attenuation coefficient corresponding to each detection region through the ultrasonic transmission information of multiple ultrasonic transmission paths, avoiding the preset assumption of the physical and chemical properties of the slurry from the source, without the need for pre-established interference factor compensation models or complex offline calibration mathematical models. The method can automatically identify the solid content detection deviation caused by interference factors and other reasons through the spatio-temporal evolution of the three-dimensional attenuation matrix, greatly improving the self-adaptability of the detection method to environmental changes and the accuracy of the solid content detection of the battery slurry to be detected.

[0052] 2. In the case of knowing the characteristics of the battery slurry to be detected in advance, the present application can achieve rapid prediction through the standard working curve for standard battery slurry with unknown solid content. For non-standard battery slurry with unknown solid content, the present application can correct the deviation in the detection of the solid content of non-standard slurry after rapid prediction through the solid content calibration mechanism. In the case of not knowing the characteristics of the battery slurry to be detected, the present application can still determine whether to trigger the solid content calibration mechanism by judging the characteristics of the battery slurry to be detected based on the predicted solid content obtained through rapid prediction. The detection mechanism of the present application breaks the dependence on the "known" premise of the slurry characteristics in traditional detection methods. Whether it is rapid screening of standard slurry or deep calibration of non-standard slurry, the "prediction-judgment-calibration" closed loop can automatically and seamlessly switch, significantly improving the engineering practicability of ultrasonic detection technology in battery slurry detection and providing higher possibility for real-time detection of slurry solid content. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 FIG. 1 shows a structural schematic diagram of an ultrasonic detection system for battery slurry solid content provided by an embodiment of the present application.

[0054] Figure 2 FIG. 3 shows the positional connection relationship between the annular probe unit and the transmission pipeline provided by an embodiment of the present application.

[0055] Figure 3 FIG. 4 shows a structural schematic diagram of the detection region on the cross section of the transmission pipeline corresponding to the ultrasonic detection part provided by an embodiment of the present application.

[0056] Figure 4 A method flow chart of the battery slurry solid content ultrasonic detection method provided by Embodiment 2 of the present application is shown.

[0057] Figure 5 is a waveform diagram of the ultrasonic transmission information shown by Embodiment 2 of the present application.

[0058] Figure 6 is a schematic diagram of the standard relationship curve between the ultrasonic transmission attenuation coefficient and the solid content shown by Embodiment 2 of the present application.

[0059] Figure 7 is a schematic diagram for embodying the second ultrasonic detection process shown by Embodiment 2 of the present application. DETAILED DESCRIPTION

[0060] The present application will be further described below in combination with the embodiments of the present application and the accompanying drawings. Embodiment 1

[0061] Embodiment 1 of the present application discloses an ultrasonic detection system for battery slurry solid content.

[0062] Referring to Figures 1-2 , the ultrasonic detection system for battery slurry solid content comprises an ultrasonic probe device and an ultrasonic detection processing device;

[0063] The ultrasonic probe device is configured to emit and receive ultrasonic transmission signals penetrating the battery slurry to be detected in the transmission pipeline to obtain ultrasonic transmission information, wherein the ultrasonic transmission information is the signal intensity of the ultrasonic transmission signals; the ultrasonic detection processing device is configured to acquire the ultrasonic transmission information in the ultrasonic probe device to calculate the actual solid content of the battery slurry to be detected, and then obtain a detection result according to the actual solid content.

[0064] Referring to Figures 1-3 In the present embodiment, the ultrasonic probe device is located at the detection section of the transmission pipeline, specifically, a ring-shaped ultrasonic detection device, one ultrasonic probe device comprises a plurality of ring-shaped probe units, the plurality of ring-shaped probe units are sequentially sleeved on the transmission pipeline along the transmission direction of the transmission pipeline, and exemplarily, in combination with Figure 2 The ultrasonic probe device of the present embodiment can comprise three ring-shaped probe units, wherein the ring-shaped probe unit 1 corresponds to the detection subunit 1, the ring-shaped probe unit 2 corresponds to the detection subunit 2, and the ring-shaped probe unit 3 corresponds to the detection subunit 3. Each ring-shaped probe unit comprises a plurality of groups (equal to or greater than 3 groups) of transceiver probe pairs, and the two transceiver probes in each group of transceiver probe pairs are distributed in a 180° symmetrical manner along the circumference of the transmission pipeline, i.e., the two transceiver probes in the transceiver probe pair are located on the cross-sectional diameter of the transmission pipeline; all the transceiver probes are directed towards the lumen of the transmission pipeline and are uniformly distributed along the circumference of the transmission pipeline; exemplarily, as shown in Figure 3As shown, the transceiving probe R1 and the transceiving probe R4, the transceiving probe R2 and the transceiving probe R5, and the transceiving probe R3 and the transceiving probe R6 are a group of transceiving probe pairs defined above.

[0065] Each transceiving probe has the function of transmitting and receiving ultrasonic waves: when the transceiving probe is the transmitting end, the transceiving probe is used to transmit ultrasonic transmission signals penetrating the slurry to one transceiving probe as the receiving end; when the transceiving probe is the receiving end, the transceiving probe is used to receive the ultrasonic transmission signals emitted by the transceiving probe as the transmitting end.

[0066] The ultrasonic detection processing device comprises a host computer, a PCIE card, an FPGA unit, a switching device, and a control device.

[0067] The host computer can be a commonly used computer, and the host computer is used to control the ultrasonic probe device to complete the entire ultrasonic detection through control instructions; the host computer is also used to obtain ultrasonic transmission information according to the corresponding ultrasonic transmission signals of each group of transmitting end and receiving end during the ultrasonic detection process, and to realize the detection of the battery slurry solid content through all the ultrasonic transmission information; specifically, the control instructions of the host computer will be described in detail in a battery slurry solid content ultrasonic detection method corresponding to the embodiment.

[0068] In the embodiment, the host computer is connected with the FPGA unit through the PCIE card, the FPGA unit is used to collect ultrasonic transmission signals at high speed and accurately control the working time sequence of the plurality of transceiving probes, the PCIE card is a high-speed data transmission interface, supports bidirectional data flow, the control instructions issued by the host computer are sent to the FPGA unit through the PCIE card, and then sent to the switching device by the FPGA unit to realize the control of the transceiving probes; the FPGA unit collects the ultrasonic transmission signals of the transceiving probes when receiving ultrasonic waves, and sends the ultrasonic transmission signals to the host computer through the PCIE card for processing and analysis by the host computer.

[0069] In specific implementation, the FPGA unit and the PCIE card can also adopt other commonly used forms in the technical field, such as the FPGA unit can also adopt other micro processing chips, and the form of the micro processing chip used can be selected as needed to meet the ultrasonic detection of the battery slurry solid content to be detected, which will not be illustrated one by one here.

[0070] The switching device is mainly used to realize the switching control of the ultrasonic wave transmitting state and the ultrasonic wave receiving state of the transceiving probes, and can adopt a commonly used switching control circuit and the like, and the switching device is adaptively connected with the transmitting circuit of the transceiving probe and the receiving circuit of the transceiving probe to realize the switching control of the ultrasonic wave transmitting state and the ultrasonic wave receiving state.

[0071] The control device can control the form of operation of the ultrasonic probe device, such as power supply to the annular probe unit; the control device is connected to the upper computer, and the upper computer is connected to the FPGA unit and the switching device, so as to cooperate with the ultrasonic probe device to realize the detection of the solid content of the battery slurry to be detected.

[0072] As can be known from the above description, the ultrasonic probe device is used to obtain the ultrasonic transmission signal of the battery slurry, and then the ultrasonic detection processing device is used to process and analyze the ultrasonic transmission signal of the battery slurry to obtain the solid content detection result of the battery slurry to be detected. The solid content detection method and process of the battery slurry to be detected can refer to the description of the method in Embodiment 2 below.

[0073] The upper computer includes a processor and a memory for storing at least one instruction, at least one program, a code set or an instruction set; the processor executes the steps of the ultrasonic detection method of the solid content of the battery slurry in Embodiment 2 below when running at least one instruction, at least one program, a code set or an instruction set.

[0074] The implementation of the method of the application will be described in detail below in combination with the above system: Embodiment 2

[0075] Embodiment 2 of the application discloses an ultrasonic detection method of the solid content of a battery slurry, before the ultrasonic detection method is applied to the solid content detection of the battery slurry to be detected, the following preparatory steps are included:

[0076] S10, constructing a standard working curve of the ultrasonic transmission characteristic value and the solid content of the standard battery slurry;

[0077] The ultrasonic transmission characteristic value refers to the propagation characteristic of the ultrasonic wave in the slurry medium when the ultrasonic wave passes through the battery slurry, which can be used to characterize the physical characteristic of the battery slurry. The ultrasonic transmission characteristic value includes but is not limited to the ultrasonic transmission attenuation coefficient. The standard working curve of the ultrasonic transmission characteristic value and the solid content of the battery slurry is used to reflect the quantitative mapping relationship between the solid content and the ultrasonic transmission characteristic value of the standard battery slurry. The standard working curve can be constructed by a series of ultrasonic transmission characteristic values of the standard battery slurry with known solid content.

[0078] Specifically, the ultrasonic transmission attenuation coefficient is taken as the ultrasonic transmission characteristic value below, and how to construct the standard working curve of the ultrasonic transmission attenuation coefficient and the solid content of the standard battery slurry is described in detail. Step S10 includes:

[0079] S11, performing first ultrasonic detection on the standard battery slurries with different solid contents respectively to obtain the ultrasonic transmission information corresponding to each solid content of the standard battery slurry;

[0080] The preset standard battery slurry with different solid contents refers to a series of standard battery slurries with known solid contents prepared in advance, and the series of known solid contents can be 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, and 60wt% respectively. The standard battery slurry refers to a battery slurry that is uniform, has no agglomeration, and has no bubbles. The standard battery slurry can be a standard battery negative electrode slurry or a standard battery positive electrode slurry, and the preparation method of the standard battery slurry is a prior art, which will not be described here. It should be noted that the series of standard battery slurries with known solid contents and the battery slurry to be measured are battery slurries of the same type, that is, the series of standard battery slurries with known solid contents and the battery slurry to be measured have the same type of solid components;

[0081] The ultrasonic transmission information is a change curve of the received signal intensity of the transceiving probe as the receiving end when receiving the ultrasonic transmission signal in the first ultrasonic detection process. In the prior art, the ultrasonic transmission information is generally converted into an electrical signal or further converted into a digital signal by devices such as an oscilloscope and a data acquisition card for output and presentation. Common output forms include voltage sequences and time-domain waveforms. The specific form of the ultrasonic transmission information can refer to Figure 5 .

[0082] The first ultrasonic detection is mainly realized by a group of transceiving probe pairs in a certain annular probe unit. Specifically, one of the transceiving probe pairs is used as the transmitting end of the ultrasonic wave, and the other is used as the receiving end of the ultrasonic transmission signal penetrating the battery slurry, and the ultrasonic wave is emitted from the transmitting end to the receiving end.

[0083] It should be particularly noted that since the standard battery slurry is a uniform, non-agglomerated, and bubble-free standard battery slurry, only one detection subunit can be used for the first ultrasonic detection of the standard battery slurry, and any two transceiving probes in the corresponding annular probe unit are selected for detection. Preferably, one transceiving probe pair in one annular probe unit is selected.

[0084] This embodiment takes the detection of the standard battery slurry with a solid content of 30wt% by the detection subunit 1 as an example. The transceiving probe R1 in the annular probe unit 1 is used as the transmitting end, and the transceiving probe R4 is used as the receiving end. At this time, the transceiving probe R1 emits ultrasonic waves along the ultrasonic wave transmission path direction of R1→R4, the standard battery slurry is subjected to the first ultrasonic detection, and the transceiving probe R4 is responsible for receiving the ultrasonic transmission signal. The host computer is responsible for collecting the changes in the intensity attenuation of the ultrasonic transmission signal received by the receiving end due to the penetration of the slurry, and obtaining the ultrasonic transmission information.

[0085] S12, obtaining an ultrasonic transmission attenuation coefficient according to the ultrasonic transmission information;

[0086] Specifically, S12 includes the following steps Sa1-Sa2:

[0087] Sa1, obtaining the received signal amplitude corresponding to each standard battery slurry with known solid content according to the ultrasonic transmission information;

[0088] Among them, reference Figure 5 The received signal amplitude is the maximum instantaneous intensity value of the ultrasound transmission signal in the ultrasound transmission information. In this embodiment, t a The signal strength value V corresponding to the point a is the received signal amplitude.

[0089] Sa2, calculates the ultrasonic transmission attenuation coefficient of standard battery slurries with different known solid contents according to the received signal amplitude;

[0090] Among them, the calculation formula of ultrasound transmission attenuation coefficient is:

[0091] ;

[0092] in, is the ultrasound transmission attenuation coefficient, A 接 is the received signal amplitude, A 发 The transmitted signal amplitude is the set signal transmission intensity, L is the transmission distance of the ultrasonic transmission signal, and the transmission distance of the ultrasonic transmission signal is the distance between the transceiver probe as the transmitting end and the transceiver probe as the receiving end.

[0093] S13, constructing a standard relationship curve between the ultrasonic transmission attenuation coefficient and the solid content of the standard battery slurry;

[0094] Specifically, S13 mainly fits the ultrasonic transmission attenuation coefficient of the standard battery slurry with a solid content of 30wt%, 35wt%, 40wt%, 50wt%, 55wt% and 60wt% respectively obtained in step S12 with the data of the corresponding solid content, and constructs a standard relationship curve between the ultrasonic transmission attenuation coefficient and the solid content of the standard battery slurry; wherein, the curve fitting can adopt the fitting method commonly used in this technical field, such as the least squares fitting method, and the specific fitting method and fitting process can be consistent with the existing technology and will not be repeated here.

[0095] For example, the standard relationship curve after least square fitting is as follows: Figure 6 As shown in FIG, the equation of the standard relationship curve between the ultrasonic transmission attenuation coefficient and the solid content of the standard battery slurry after fitting in this embodiment is:

[0096] ;

[0097] Where x is the solid content and y is the ultrasonic transmission attenuation coefficient.

[0098] S14, correcting the standard relationship curve of the standard battery slurry;

[0099] Specifically, in order to ensure the accuracy and reliability of the standard relationship curve, a series of standard battery slurries with known solid content can be selected, for example, a lithium ion battery negative standard slurry with a solid content of 45%, and the first ultrasonic detection is performed under the same experimental conditions as step S12 to calculate the corresponding ultrasonic transmission attenuation coefficient. The obtained ultrasonic transmission attenuation coefficient is input into the standard relationship curve in step S13 to calculate the predicted solid content, and compared with the actual solid content to calculate the deviation of the predicted solid content from the actual solid content.

[0100] If the deviation exceeds the preset deviation threshold, the quantitative relationship curve of the ultrasonic transmission attenuation coefficient and the solid content of the standard battery slurry is corrected and optimized, and the corrected and optimized quantitative relationship curve is used as the new standard working curve.

[0101] If the deviation does not exceed the preset deviation threshold, the standard working curve obtained in step S13 remains unchanged.

[0102] Specifically, when the deviation exceeds the preset deviation threshold, the quantitative relationship curve obtained in step S13 is corrected and optimized; wherein the correction and optimization method can be:

[0103] A new fitting method is used to re-fit to obtain a new fitted quantitative relationship curve equation. The ultrasonic transmission attenuation coefficient is input into the new fitted quantitative relationship curve equation, and the new predicted solid content is output and compared with the actual solid content to calculate the new deviation of the new predicted solid content from the actual solid content. If the new deviation does not exceed the preset deviation threshold, the correction and optimization are completed, and the new fitted quantitative relationship curve equation is used as the standard working curve. If the new deviation exceeds the preset deviation threshold, a series of ultrasonic transmission signals of standard battery slurries with known solid content need to be collected again, and steps S11-S14 are repeated until the deviation of the predicted solid content from the actual solid content does not exceed the preset deviation threshold.

[0104] It should be noted that the deviation of the predicted solid content from the actual solid content mentioned in step S14 can be the absolute value of the difference between the two, and the preset deviation threshold can be selected as needed, such as the preset deviation threshold can be 0.5%. The specific accuracy requirement of the ultrasonic detection of the battery slurry solid content is related.

[0105] After the above steps S11-S14, the standard working curve is obtained, and the method further comprises: Figure 4 The ultrasonic detection method for the solid content of the battery slurry of the embodiment further comprises:

[0106] S100, performing first ultrasonic detection on the battery slurry to be measured in the transmission pipeline to obtain ultrasonic transmission information, and obtaining a predicted solid content according to the ultrasonic transmission information and a standard working curve.

[0107] Wherein, the first ultrasonic detection and the definition of ultrasonic transmission information are the same as in S11; Specifically, obtaining the predicted solid content according to the ultrasonic transmission information in S100 mainly includes:

[0108] S110, obtaining an ultrasonic transmission attenuation coefficient according to the ultrasonic transmission information;

[0109] Wherein, the steps of S110 are the same as S12 described above, and will not be repeated here.

[0110] S120, substituting the ultrasonic transmission attenuation coefficient into the standard working curve to obtain the predicted solid content.

[0111] It needs to be particularly pointed out that in S100, the battery slurry to be measured can be a standard battery slurry with unknown solid content, or a non-standard battery slurry with unknown solid content, wherein the standard battery slurry with unknown solid content refers to the battery slurry with unknown solid content but uniform, no agglomeration, no bubbles in the transmission process, and the non-standard battery slurry with unknown solid content refers to the battery slurry with unknown solid content but possibly uneven, agglomeration or bubbles in the transmission process.

[0112] When the battery slurry to be measured is a standard battery slurry with unknown solid content, the solid content detection of the battery slurry to be measured can be directly calculated by the ultrasonic transmission information obtained by the first ultrasonic detection and the standard working curve obtained by step S10;

[0113] When the battery slurry to be measured is a non-standard battery slurry with unknown solid content, due to the possible unevenness, agglomeration or bubbles, the attenuation of the ultrasonic transmission path will present spatial difference, at this time, only relying on the mapping relationship between the ultrasonic transmission attenuation coefficient and the solid content in the above standard working curve, the calculation of the solid content of the battery slurry to be measured will cause an unavoidable measurement deviation, which is specifically:

[0114] The agglomeration area will enhance the ultrasonic scattering, and the bubble area will produce strong reflection, resulting in abnormal increase of the ultrasonic transmission attenuation coefficient, which will cause large deviation between the predicted solid content obtained by S100 and the actual solid content of the battery slurry to be measured, seriously affecting the detection precision and accuracy of the solid content of the non-standard battery slurry. Therefore, the detection of the solid content of the non-standard slurry needs to introduce the solid content calibration mechanism of subsequent steps S200-S300 to improve the detection precision of the solid content of the slurry and promote the application and optimization of ultrasonic detection technology in the real-time monitoring of the continuous production process of the battery slurry.

[0115] S200, when the battery slurry to be measured is a standard battery slurry with unknown solid content, the predicted solid content is directly taken as the actual solid content.

[0116] S300, otherwise, whether to trigger the solid content calibration mechanism is judged according to the predicted solid content.

[0117] S400, if yes, the calibration parameter is obtained through the solid content calibration mechanism, and the actual solid content is obtained according to the calibration parameter and the predicted solid content.

[0118] S500, if no, the predicted solid content is directly taken as the actual solid content.

[0119] Specifically, step S300 includes:

[0120] S310, the second ultrasonic detection is performed on the battery slurry to be measured to obtain ultrasonic transmission information corresponding to each detection subunit;

[0121] Among them, the second ultrasonic detection is mainly realized by transmitting and receiving ultrasonic waves by a group of transceiving probe pairs in different detection subunits in continuous different first detection periods. For example, refer to Figure 7 The second ultrasonic detection of the battery slurry to be measured uses three detection subunits in time sequence, and each first detection period corresponds to a detection subunit. In each detection subunit, one transceiving probe of a group of transceiving probe pairs is taken as the transmitting end, and the other transceiving probe is taken as the receiving end. The detection subunit 1 starts the second ultrasonic detection at t1, the detection subunit 2 starts the second ultrasonic detection at t2, and the detection subunit 3 starts the second ultrasonic detection at t3. The ultrasonic transmission information corresponding to each detection subunit is obtained.

[0122] It should be noted that t1, t2 and t3 are preset transmission times. When the distance between adjacent detection subunits is the same, the transmission time of each detection subunit can be accurately preset. That is, when the battery slurry to be measured flows in the transmission pipeline at a specific flow rate v, the interval Δt (i.e. t2-t1, t3-t2) between adjacent transmission times needs to satisfy the following relationship:

[0123] Δt=s / (v・k),

[0124] Where Δt is the interval between adjacent transmission times, v is the flow rate of the battery slurry to be measured, s is the distance between adjacent detection subunits, and k is a time compensation coefficient greater than 1. The time compensation coefficient k can be determined by fluid Reynolds number correlation method, and the calculation formula is:

[0125] k=1.05+0.00005・Re;

[0126] Wherein, Re is the Reynolds number corresponding to the battery slurry to be measured.

[0127] In addition, the time compensation coefficient k can also be determined by other methods commonly used in the art, which can be selected as needed, and other methods commonly used in the art will not be repeated here.

[0128] The setting of the interval Δt between the adjacent two emission times can ensure that after the slurry in a certain area flows through the annular probe unit 1, it moves to the detection area of the annular probe unit 2 after Δt, and then reaches the detection area of the annular probe unit 3 after another Δt.

[0129] S320, obtaining the ultrasonic transmission attenuation coefficient corresponding to each detection subunit according to the ultrasonic transmission information;

[0130] Wherein, S320 is the same as S110 and S12 described above, which will not be repeated here.

[0131] S330, obtaining the multiple comparative solid contents of the battery slurry to be measured according to all ultrasonic transmission attenuation coefficients and the standard working curve;

[0132] Wherein, the comparative solid content is mainly obtained by inputting the ultrasonic transmission attenuation coefficients of multiple battery slurries to be measured into the standard working curve, and the comparative solid content corresponds to each detection subunit one by one.

[0133] It should be particularly pointed out that the first comparative solid content is actually the predicted solid content in S100; in the case that the type of the battery slurry to be measured is known in advance, the calculation of the predicted solid content in step S100 will be included in the second ultrasonic detection in step S300, that is, the starting time of the first ultrasonic detection in S100 is taken as the first time of the start of the second ultrasonic detection, and the predicted solid content calculated by the first ultrasonic detection is directly taken as the comparative solid content at the first time of the second ultrasonic detection; in the case that the type of the battery slurry to be measured cannot be determined in advance, the first ultrasonic detection in step S100 and the second ultrasonic detection in step S300 are performed separately.

[0134] S340, judging whether to trigger the solid content calibration mechanism according to all comparative solid contents;

[0135] Specifically, S340 includes:

[0136] S341, calculating the first deviation between adjacent two comparative solid contents;

[0137] Wherein, the first deviation refers to the absolute difference between adjacent two comparative solid contents, that is, the absolute value of the difference between the two comparative solid contents accounts for the proportion of the previous comparative solid content, which is used to represent the short-term fluctuation amplitude of the solid content in the adjacent first detection period.

[0138] S342, calculate a second deviation between a first contrast solid content and a last contrast solid content arranged in a time sequence;

[0139] The second deviation refers to a cumulative difference between the first contrast solid content and the last contrast solid content arranged in a time sequence, i.e. a proportion of an absolute value of the difference to the first contrast solid content, for reflecting an overall drift degree of the solid content in a continuous detection time period.

[0140] S343, determine whether to trigger a solid content calibration mechanism according to the first deviation, the second deviation, and a preset trigger condition;

[0141] Specifically, the preset trigger condition includes one or more of the following situations:

[0142] Any first deviation exceeds a preset first threshold value;

[0143] The second deviation exceeds a preset second threshold value;

[0144] The first threshold value and the second threshold value can be selected as needed, and are specifically related to the accuracy requirement of the ultrasonic detection of the battery slurry solid content to be detected; the first threshold value can be 0.2%, and the second threshold value can be 0.8%.

[0145] From the above description, it can be seen that when the first deviation exceeds the first threshold value and / or the second deviation exceeds the second threshold value, it is determined that the determination result is yes; otherwise, it is determined that the determination result is no.

[0146] Specifically, the solid content calibration mechanism in S400 includes:

[0147] S410, dividing a cross section of the ultrasonic detection part corresponding to the transmission pipeline into a plurality of detection regions;

[0148] In this embodiment, the cross section of the ultrasonic detection part corresponding to the transmission pipeline is mainly divided by an equidistant grid division method to obtain a plurality of detection regions, taking the first region at the lower left corner as the starting point, and the positions of the divided detection regions in the coordinate system Naming each detection region , representing that the detection region is located in the row and the column, increasing from left to right, increasing from bottom to top, and in this embodiment, 1 .

[0149] S420, performing a third ultrasonic detection on the battery slurry to be detected to obtain a region attenuation coefficient corresponding to each detection region;

[0150] The third ultrasonic detection is mainly realized by all the transceiving probes in the detection subunit, and an example is shown with reference to Figure 3 The third ultrasonic detection of the battery slurry to be detected is mainly realized by the detection subunit 1; during the detection, an ultrasonic transmission path is formed between every two transceiving probes in the annular probe unit 1; specifically, S420 comprises:

[0151] S421, performing the third ultrasonic detection on the battery slurry to be detected according to a preset path rotation rule to obtain a received signal amplitude corresponding to each ultrasonic transmission path;

[0152] The path rotation rule is used to form different ultrasonic transmission paths by sequentially switching every two transceiving probes as a combination of a transmitting end or a receiving end in the annular probe unit to cover all possible ultrasonic transmission paths in the detection area; specifically, S421 comprises:

[0153] S4211, sequentially selecting one transceiving probe as a transmitting end and generating a corresponding ultrasonic transmission cycle after the selection of the transmitting end each time;

[0154] The total number of the ultrasonic transmission cycles is the total number of the transceiving probes in the annular probe unit, and each transceiving probe has only one opportunity to serve as a transmitting end in all the ultrasonic transmission cycles.

[0155] S4212, after obtaining each ultrasonic transmission cycle, sequentially selecting one transceiving probe other than the current transmitting end as a receiving end and generating a sub-cycle in the current ultrasonic transmission cycle after the selection of the receiving end each time.

[0156] S4213, in each sub-cycle, performing an ultrasonic transmission detection based on the ultrasonic transmission path corresponding to the current transmitting end and the current receiving end to obtain a received signal amplitude corresponding to each ultrasonic transmission path;

[0157] The determination principle of the received signal amplitude is the same as that of Sa1, which is not described herein again; the transmitting end corresponding to each ultrasonic transmission cycle and the receiving end corresponding to each sub-cycle form an ultrasonic transmission path; if the annular probe unit 1 includes three transceiving probe pairs, the transceiving probe pairs are R1-R4, R2-R5 and R3-R6, and a maximum of 30 ultrasonic transmission paths can be formed between all the transceiving probes, including R1→R2, R1→R3,..., and R6→R5; specifically, the ultrasonic transmission detection based on the ultrasonic transmission path corresponding to the current transmitting end and the current receiving end means that the current transmitting end transmits an ultrasonic transmission signal to the current receiving end through the ultrasonic transmission path corresponding to the sub-cycle.

[0158] It should be particularly pointed out that in step S4212, in order to improve the detection efficiency, the number of ultrasonic transmission paths is limited in this embodiment, only one of the two ultrasonic transmission paths formed by the same two transceiving probes is reserved, that is, when the first ultrasonic transceiving round composed of the transmitting end R1 obtains the ultrasonic transmission path R1→R2, the second ultrasonic transceiving round composed of the transmitting end R2 will exclude R1 which has been used as the transmitting end in the selection of the receiving end, at this time, the second ultrasonic transceiving round will not obtain the ultrasonic transmission path R2→R1 again. Specifically, assuming that there are transceiving probe pairs R1-R3 and R2-R4 at present, the following Table 1 clearly shows the association relationship among the ultrasonic transceiving rounds, sub-rounds and ultrasonic transmission paths of R1-R4:

[0159] Table 1:

[0160]

[0161] It should be noted that the conventional ultrasonic detection process can accurately collect the overall attenuation of the ultrasonic transmission signal in the entire propagation process, but it cannot obtain the specific attenuation of the ultrasonic transmission signal in the actual propagation process; while in this embodiment, each ultrasonic transmission path passes through a specific one or more detection areas.

[0162] Through the setting of this embodiment, the ultrasonic detection processing device can decouple and analyze the attenuation process of the ultrasonic transmission signal in each detection area; specifically, when the ultrasonic transmission signal passes through multiple detection areas in turn, its overall attenuation coefficient can be calculated by segmenting each detection area.

[0163] Next, the relationship between the ultrasonic propagation path and the detection area will be described, which is illustrated as follows:

[0164] Referring to Figure 3 , if R1 is the transmitting end and R2 is the receiving end, the ultrasonic wave emitted by R1 passes through the detection area and the detection area in turn, and is received by R2, then the ultrasonic propagation path R1→R2 is considered to be associated with the detection area When the transceiving probe R1 is the transmitting end, the corresponding relationship between each ultrasonic propagation path and the detection area is shown in Table 2:

[0165] Table 2:

[0166]

[0167] It should be noted that in S421, the third ultrasonic detection of the battery slurry to be detected can be implemented by using one annular probe unit or multiple annular probe units, and each annular probe unit needs to perform the above-mentioned step S420 to obtain the area attenuation coefficient of all detection areas in the detection subunit corresponding to the current annular probe unit; in order to simplify the solid content calibration mechanism, the application preferably uses one annular probe unit.

[0168] In addition, it should be particularly pointed out that the first detection period mentioned in step S310 and the second detection period mentioned in step S420 in the embodiment both represent an ultrasonic detection period, but the detection steps actually performed by the transceiving probes in the corresponding detection period are different.

[0169] Regarding the first detection period, in combination with Figure 7 , the detection logic of the second ultrasonic detection is cross-unit segmented detection: in the process of moving a certain segment of the battery slurry to be detected along the slurry transmission direction from the first detection subunit to the third detection subunit, when the target slurry at t1 is in the first detection unit, the first ultrasonic detection of the battery slurry to be detected is completed by the annular probe unit 1 corresponding to the first detection unit through the transmitting end and the receiving end, when the target slurry at t2 is in the second detection unit, the second ultrasonic detection of the battery slurry to be detected is completed by the annular probe unit 2 corresponding to the second detection unit through the transmitting end and the receiving end, and so on. Different first detection periods actually correspond to the same segment of the battery slurry to be detected, and the ultrasonic transmission information of the battery slurry to be detected in the corresponding detection subunit can be obtained during the period, so as to obtain the corresponding ultrasonic transmission attenuation coefficient. Figure 7 For example, the embodiment completes three second ultrasonic detections in three first detection periods.

[0170] Regarding the second detection period, in combination with Table 1 above, in the process of moving the battery slurry to be detected along the slurry transmission direction through a certain detection subunit, in one second detection period, all transceiving probes in the annular probe unit corresponding to the detection subunit complete the ultrasonic detection of all ultrasonic transmission paths according to the above-mentioned path rotation rule. The second detection period of the embodiment includes the reception and transmission of the ultrasonic signals corresponding to a plurality of ultrasonic transmission paths, for example, if there are 20 ultrasonic transmission paths corresponding to the detection subunit, the reception and transmission of the ultrasonic signals need to be performed 20 times in the second detection period. Different second detection periods actually correspond to the ultrasonic transmission information of the same detection subunit segment, and the area attenuation coefficient of each detection area in the cross section corresponding to the detection subunit can be obtained during the period.

[0171] It should be noted that the total time of one second detection cycle must be less than or much less than the first detection cycle, which can reduce the data misalignment caused by the significant displacement of the battery slurry to be detected within the cycle.

[0172] S422, obtaining a region attenuation coefficient corresponding to each detection region according to all received signal amplitudes;

[0173] Specifically, S422 mainly includes the following steps:

[0174] S4221, determining a target function formula to obtain a plurality of linear equations corresponding to each ultrasonic transmission path;

[0175] The target function formula is used to reflect the quantitative relationship between the preset transmission signal amplitude, the received signal amplitude, and the region attenuation coefficient in all corresponding detection regions in the ultrasonic transmission path. Through this relationship, the actual attenuation of the battery slurry to be detected corresponding to one or more detection regions through which the ultrasonic wave is transmitted under different ultrasonic transmission paths can be calculated to obtain the region attenuation coefficient corresponding to each detection region, thereby reflecting the solid content distribution characteristics of the battery slurry to be detected at different spatial positions. Each linear equation includes one or more unknown region attenuation coefficients. The target function formula of the present embodiment is an ultrasonic attenuation equation. In each ultrasonic transmission path, the attenuation of the ultrasonic transmission signal satisfies the following ultrasonic attenuation equation:

[0176] ;

[0177] wherein, is the transmission signal amplitude; is the received signal amplitude; is the detection region set corresponding to the kth ultrasonic transmission path, is the region attenuation coefficient corresponding to the detection region (i, j), is the propagation distance of the ultrasonic transmission signal in the detection region (i, j), which can be calculated by geometric coordinates, for example, when the path passes through the diagonal of the grid, = * the length of the detection region.

[0178] S4222, determining an effective transmission path according to the ratio of the received signal amplitude to the transmission signal amplitude;

[0179] The effective transmission path refers to the ultrasonic transmission path corresponding to the ratio of the received signal amplitude to the transmission signal amplitude within the preset ratio range, which can be selected as needed. Exemplarily, the preset ratio range can be 30%~90% to exclude as much as possible the data of the transmission signal attenuation distortion caused by large agglomerates or large bubbles.

[0180] S4223, substituting the received signal amplitude corresponding to each effective transmission path and the preset transmission signal amplitude into the corresponding linear equation to obtain a multi-equation set composed of all linear equations;

[0181] After all the received signal amplitudes and the transmission signal amplitudes are filled into the corresponding linear equations, the multi-equation set composed of all the linear equations is an equation set for solving multiple unknowns, i.e., the region attenuation coefficients corresponding to each detection region.

[0182] S4224, calculating the region attenuation coefficients corresponding to each detection region according to the multi-equation set;

[0183] Specifically, S4224 includes:

[0184] S42241, obtaining a path-region propagation matrix corresponding to the multi-equation set;

[0185] The path-region propagation matrix is in the form of a matrix of the multi-equation set. Specifically, S42241 includes the following steps:

[0186] S422411, converting the multi-equation set into an attenuation matrix expression;

[0187] In this embodiment, the natural logarithm of each linear equation in the multi-equation set is first taken on both sides to convert it into a linear equation , and then The final attenuation matrix expression is as follows: .

[0188] S422412, constructing the path-region propagation matrix according to the attenuation matrix expression;

[0189] This step mainly combines the attenuation matrix expressions of all effective transmission paths, i.e., the linear equations, into a matrix form , y is the dependent variable vector, with a dimension of Mx1, M is the total number of effective transmission paths, and y specifically refers to the logarithmic amplitude difference y k , i.e. ; X is the independent variable matrix, with a dimension of MxN 2 , N represents the total number of detection regions, each row of X corresponds to an effective transmission path, and each column corresponds to a detection region, The value rule of X is as follows:

[0190] ;

[0191] is the vector of the region attenuation coefficients to be solved, with a dimension of N 2Xi, the element is the attenuation coefficient of each detection region , all attenuation coefficients are arranged in the order of coordinates of the detection region, ; is a noise vector, including measurement noise and model error, is a preset value, subject to normal distribution , wherein is a noise variance, which can be preset through historical data of ultrasonic detection, which is a prior art in ultrasonic detection and will not be described here.

[0192] S42242, according to the path-region propagation matrix, the attenuation matrix expression is solved, and the region attenuation coefficient corresponding to each detection region is obtained;

[0193] (1) when the effective transmission path meets the preset direct solving condition, the multiple equation set can be solved by least square method to obtain the region attenuation coefficient corresponding to each detection region;

[0194] Wherein, the direct solving condition includes the minimum path number condition and the path distribution condition, wherein the minimum path number can be set as several multiples of the number of detection regions (the multiple must be greater than or equal to 1), which is mainly used to preliminarily ensure the solvability of the multiple equation set; the path distribution condition is mainly used to further maintain the stability of the solution of the multiple equation set, and the path distribution condition needs to be set according to the number of transceiving probes and the number of detection regions. For example, the path distribution condition can be set to at least pass through 2 effective transmission paths for each detection region. The minimum path number condition and the path distribution condition help to ensure the least square solution of the multiple equation set, reduce the parameter estimation error, avoid the solution sensitive to noise, and thus greatly improve the accuracy of the region attenuation coefficient.

[0195] Specifically, the multiple equation set is solved by least square method, including the following steps:

[0196] Sb1, set up the first objective function, wherein the expression of the first objective function is:

[0197] ,

[0198] Wherein, represents the error term, which is specifically the residual sum of squares between the predicted attenuation value Xα of all effective transmission paths and the actual measured value y, that is, represents .

[0199] Sb2, based on the first objective function, the partial derivative of α is solved and the derivative is zero, and the first partial derivative expression is obtained;

[0200] Wherein, the first partial derivative expression is:

[0201] ,

[0202] Sb3, obtaining a first normal linear equation set based on the first partial derivative expression;

[0203] wherein the expression of the first normal linear equation set is:

[0204] .

[0205] Sb4, obtaining a plurality of regional attenuation coefficients corresponding to each detection region based on the first normal linear equation set;

[0206] wherein the expression of the least square estimation is:

[0207] wherein, is a vector of the regional attenuation coefficients of the detection regions, and each element corresponds to an attenuation coefficient of a detection region .

[0208] It should be noted that, in addition to the least square method, any method that can satisfy the direct solution of a multivariate equation set can be used as a direct solution method, and the embodiment is not limited.

[0209] (ii) when the effective transmission path does not satisfy the direct solution condition, the multivariate equation set is solved by iterative regularization to obtain a regional attenuation coefficient corresponding to each detection region.

[0210] It should be noted that the embodiment can use the iterative regularization method commonly used in the art, or any method that can accurately solve the regional attenuation coefficient, including but not limited to the Tikhonov regularization method.

[0211] Specifically, the steps of solving by using the Tikhonov regularization method include:

[0212] Sc1, establishing a second objective function;

[0213] wherein the expression of the second objective function is:

[0214] ,

[0215] wherein, represents a regularization term, which is used to constrain the smoothness of the solution; D is a two-dimensional first-order difference matrix with a dimension of KxN 2 (K is the total number of adjacent regions in the horizontal and vertical directions), and the calculation formula of K is K=2Nx(N-1); is a regularization parameter.

[0216] It should be noted that the construction rule of the two-dimensional first-order difference matrix is as follows:

[0217] Horizontal direction difference: if the detection region (i, j) is adjacent to its right detection region (i, j+1), then in the corresponding row of the two-dimensional first-order difference matrix D, D (i,j) = -1, D (i,j+1) = -1, and the rest of the elements are 0.

[0218] Vertical direction difference: if the detection region (i, j) is adjacent to its right detection region (i+1, j), then in the corresponding row of the two-dimensional first-order difference matrix D, D (i,j) = -1, D (i+1,j) = -1, and the rest of the elements are 0.

[0219] It should be noted that the cross section of the transmission pipeline in which the annular probe unit is sleeved is divided into an N×N grid, and there are a total of N 2 detection regions, each region corresponding to a column of the two-dimensional first-order difference matrix, there are N-1 pairs of adjacent regions in each row in the horizontal direction, a total of N rows, the number of pairs of adjacent regions in the horizontal direction is N×(N-1); there are N-1 pairs of adjacent regions in each column in the vertical direction, a total of N columns, the number of pairs of adjacent regions in the vertical direction is N×(N-1); the total number of pairs of adjacent regions in the horizontal and vertical directions is the sum of the number of pairs of adjacent regions in the horizontal direction and the number of pairs of adjacent regions in the vertical direction, that is, 2N×(N-1).

[0220] For example, as Figure 3 shown, the cross section of the transmission pipeline in which the annular probe unit is sleeved is divided into a 3×3 grid, that is, N is 3, the total number of detection regions N 2 is 9, and the total number of pairs of adjacent regions in the horizontal and vertical directions K is 12.

[0221] It should be noted that the two-dimensional first-order difference matrix can suppress high-frequency noise of the solution and enhance spatial continuity by constraining the difference (gradient) of the attenuation coefficient of adjacent regions.

[0222] Since the solid content distribution of the battery slurry usually has local uniformity (similar physical properties of adjacent regions), the two-dimensional first-order difference matrix can effectively capture the gradient changes in the horizontal and vertical directions, and avoid non-physical oscillations in the reconstruction results.

[0223] It should be noted that the regularization parameter , the initial value of the regularization parameter λ init may be set to 0.05 as the starting point of iterative optimization; the regularization parameter needs to be dynamically adjusted, and the dynamic adjustment method can be the L curve method.

[0224] Specifically, the method for dynamically adjusting the regularization parameter by the L curve method comprises the following steps:

[0225] calculating different regularization parameters The solution , record the residual norm Reconciliation norm ,draw and The curve with the maximum curvature corresponds to .

[0226] Sc2, based on the second objective function, find the partial derivative of α and set the derivative to zero, and get the second normal linear equation system, where the expression of the second normal linear equation system is:

[0227]

[0228] Sc3, based on the second normal linear equations, the conjugate gradient method is used to iterate and obtain the attenuation coefficients of all regions corresponding to each detection area;

[0229] It should be noted that since the matrix Symmetric positive definite, using conjugate gradient method iteration can avoid the high computational complexity of direct matrix inversion. Conjugate gradient method iteration is a commonly used conjugate gradient method iteration technique in this field; wherein, the conjugate gradient method iteration is used to obtain all regional attenuation coefficients corresponding to each detection area, including:

[0230] Sc31, initialization of conjugate gradient method;

[0231] Setting the initial solution , illustratively, ;

[0232] Calculate initial residuals , ;

[0233] Determine the initial search direction , ;

[0234] Sc32, iterative update solution and residual;

[0235] Loop through the following steps ( ), specifically:

[0236] Calculation step size , , where the numerator is the inner product of the current residual, and the denominator is the result of the interaction between the search direction and the system matrix;

[0237] Update the solution vector,

[0238] Update the residual,

[0239] Calculate the convergence coefficient ,

[0240] Generate a new search direction,

[0241] Termination condition judgment: the relative change of the solution of the adjacent two iterations is less than 0.5% or the number of iterations ;

[0242] If any condition is met, the loop is terminated, and the solution is output .

[0243] It should be noted that if the solution of the region attenuation coefficient per unit transmission distance of a certain detection region obtained in step S42242 is negative, i.e. , it needs to be corrected, and the specific correction method can be:

[0244] If the mean value of the adjacent detection region corresponding to the detection region , then ; otherwise .

[0245] It should be noted that in step S42242, the solution of the region attenuation coefficient per unit transmission distance corresponding to each detection region obtained can be one or more; when the solution of the region attenuation coefficient per unit transmission distance corresponding to a certain detection region is one, its value is directly taken as the region attenuation coefficient; when the solution of the region attenuation coefficient per unit transmission distance corresponding to a certain detection region is multiple, the average value thereof is taken as the region attenuation coefficient.

[0246] When all the detection regions passed by the effective transmission paths are not fully covered by the divided detection regions, i.e., there are uncovered detection regions, wherein the uncovered detection region is a detection region not passed by all the effective transmission paths; it should be noted that when there are uncovered detection regions, the above methods cannot obtain the region attenuation coefficient of the uncovered detection region, therefore, the region attenuation coefficient of the uncovered detection region needs to be assigned, and specifically, the method for assigning the region attenuation coefficient of the uncovered detection region is:

[0247] Determine the number of adjacent detection regions of the uncovered detection region;

[0248] If the number of adjacent detection regions is greater than or equal to 2, take the average value of the adjacent region attenuation coefficients as the region attenuation coefficient of the uncovered detection region;

[0249] If the number of adjacent detection regions is less than 2, the uncovered detection region is determined as a corner isolated detection region, and the stable value The region attenuation coefficient of the uncovered detection region; it should be noted that the adjacent detection region refers to the detection region directly contacting the current detection region horizontally (left / right) or vertically (up / down), and does not include the diagonally adjacent detection region.

[0250] Further, the determination method of the stable value is as follows:

[0251] The region attenuation coefficient of the detection region corresponding to the previous T-1 second detection periods is obtained.

[0252] If the standard deviation of the region attenuation coefficients of the detection regions corresponding to the previous T-1 second detection periods is less than the standard deviation threshold, the average value of the region attenuation coefficients of the detection regions corresponding to the previous T-1 second detection periods is taken as the stable value .

[0253] If the standard deviation of the region attenuation coefficients of the detection regions corresponding to the previous T-1 second detection periods is greater than or equal to the standard deviation threshold, the region attenuation coefficient of the detection region corresponding to the previous second detection period is taken as the stable value .

[0254] It should be noted that the standard deviation threshold can be selected as needed, such as the standard deviation threshold being 0.05.

[0255] It should be noted that when there is an uncovered detection region, the uncovered detection region can be marked as a low-confidence region, and based on the current low-confidence region position, subsequent effective transmission paths passing through the low-confidence region can be added, such as adjusting the definition of the effective transmission path or adjusting the installation position of the optimized transceiver probe or increasing the number of transceiver probes in the ring probe unit.

[0256] S430, based on the region attenuation coefficient corresponding to each detection region and the corresponding detection region, a two-dimensional attenuation distribution matrix is generated.

[0257] The expression of the two-dimensional attenuation distribution matrix is as follows:

[0258]

[0259] Each element in the two-dimensional attenuation distribution matrix is the region attenuation coefficient of the detection region (i, j).

[0260] It can be understood that the region attenuation coefficient of the detection region (i, j) represents the ultrasonic attenuation capability of the i-th row and j-th column detection region in the cross section, and the greater the value of the region attenuation coefficient, the greater the ultrasonic energy attenuation of the detection region; the two-dimensional attenuation distribution matrix is used to reflect the two-dimensional distribution of the region attenuation coefficients in each detection region in the current second detection period, that is, the attenuation coefficient distribution on a two-dimensional cross section of the battery slurry to be measured, thereby providing basic data for subsequent spatial distribution analysis and dynamic calibration of the solid content.

[0261] S440, according to the two-dimensional attenuation distribution matrix in the plurality of continuous second detection periods, stacking the matrix along the time dimension to form a three-dimensional attenuation distribution matrix ;

[0262] wherein the three-dimensional attenuation distribution matrix has a dimension of N x N x T (T is the number of second detection periods), and the element of the three-dimensional attenuation distribution matrix is ; the three-dimensional attenuation distribution matrix is used to reflect the three-dimensional distribution of all region attenuation coefficients in a detection subunit in the continuous T second detection periods; for example, when N is 3 and T is 5, the expression of the three-dimensional attenuation distribution matrix is:

[0263] .

[0264] S450, obtaining a calibration parameter based on the three-dimensional attenuation distribution matrix ;

[0265] wherein the calibration parameter is used to fit and correct the deviation of the predicted solid content, correct the influence of the system inherent error and the spatial and temporal fluctuation of the attenuation coefficient, so as to obtain the actual solid content of the battery slurry to be measured, realize accurate compensation of the detection deviation caused by real abnormalities such as bubbles, agglomeration, uneven dispersion, and to a certain extent, suppress random noise interference; specifically, the step S450 comprises:

[0266] S451, performing anomaly detection on the three-dimensional attenuation distribution matrix , identifying the abnormal region in the three-dimensional attenuation distribution matrix , and extracting the elements of the abnormal region;

[0267] wherein the anomaly detection of the embodiment is LOF outlier detection, and specifically, the steps of the LOF outlier detection comprise:

[0268] for each detection region (i, j), calculating the local outlier factor (LOF) of the time series by the LOF algorithm, that is, wherein the expression of the time series is:

[0269] .

[0270] Specifically, the abnormal region determination method comprises:

[0271] determining whether the local outlier factor is greater than a local outlier factor threshold value, and when the local outlier factor is greater than the local outlier factor threshold value, marking as a candidate abnormal region, wherein the local outlier factor threshold value can be selected as needed, and exemplarily, the local outlier factor threshold value can be 1.5;

[0272] For the candidate abnormal region, it is checked whether there are two consecutive second detection period attenuation coefficient mutations exceeding a mutation threshold value, wherein the mutation threshold value can be selected as needed, and exemplarily, the mutation threshold value can be 20%; when there are two consecutive second detection period attenuation coefficient mutations exceeding the mutation threshold value, the corresponding candidate abnormal region is marked as an abnormal region.

[0273] The specific steps of extracting the elements of the abnormal region are: recording the position of the abnormal region and the time sequence corresponding to the abnormal region.

[0274] S452, generating a to-be-verified feature matrix based on the elements of the abnormal region;

[0275] Based on the position of the abnormal region and the time sequence corresponding to the abnormal region, a to-be-verified feature matrix is generated, wherein the dimension of the to-be-verified feature matrix is m x (T+2), wherein m is the number of abnormal regions, and the structure of each row of the to-be-verified feature matrix is The expression is:

[0276] ,

[0277] Wherein, the first-2 columns are abnormal region coordinates (i, j), and the 3-(T+2) columns are the attenuation coefficient sequence of the abnormal region in T second detection periods.

[0278] S453, determining an abnormal connected domain based on the to-be-verified feature matrix;

[0279] Specifically, the abnormal connected domain is composed of one or several abnormal regions, and each abnormal connected domain includes at least one abnormal region or a plurality of spatially adjacent abnormal regions.

[0280] It should be noted that the spatially adjacent abnormal regions only consider the upper, lower, left and right adjacent abnormal regions, and do not include the diagonal adjacent abnormal regions.

[0281] When the abnormally connected domain is a single abnormal region, that is, the abnormally connected domain is an isolated point, it is necessary to use isolated point filtering to determine that it is random noise and not participate in the calibration. Isolated point filtering can suppress noise and avoid miscalibration.

[0282] When the abnormal connected domain is a continuous abnormal region formed by merging multiple spatially adjacent abnormal regions, the specific merging steps include:

[0283] Initialize the marking matrix: Create a marking matrix M of the same size as the detection grid, where the dimension of the marking matrix M is N×N, the initial value of the elements in the marking matrix M is 0, the coordinates (i, j) of the abnormal area in the marking matrix M are marked as 1, and the rest are 0.

[0284] Connected domain search and merging: traverse the marking matrix M, and for each unit (i, j) marked as 1 and not visited, start DFS to search its four neighbors, mark all the connected abnormal areas found as the same connected domain, and assign a unique label.

[0285] It should be noted that abnormally connected domains can identify true anomalies and distinguish random noise from true anomalies. For example, if anomalies in the solids content of a battery slurry (such as agglomeration or uneven stirring) are detected, they typically cover a continuous detection area. Analysis of abnormally connected domains can effectively identify solids content anomalies caused by agglomeration or uneven stirring.

[0286] S454, extracting the feature vector of each abnormal connected domain, and constructing an abnormal sub-feature matrix based on the feature vector of each abnormal connected domain and the corresponding abnormal connected domain;

[0287] Specifically, a corresponding feature vector is extracted from each abnormal connected domain, where the feature vector refers to the average attenuation deviation and the attenuation fluctuation coefficient.

[0288] The formula for calculating the average attenuation deviation is:

[0289]

[0290] in, represents the average attenuation deviation; represents the mean attenuation coefficient of the same detection area with the historical mean, calculated based on the data of T−1 second detection cycles, The calculation formula is:

[0291] ;

[0292] It represents the mean attenuation coefficient of all detection areas in the abnormal connected domain in the current period. The calculation formula is:

[0293] ,

[0294] wherein, is the number of detection regions constituting the abnormal connected domain.

[0295] The calculation formula of the attenuation fluctuation coefficient is:

[0296]

[0297] wherein, represents the attenuation fluctuation coefficient, and calculates the standard deviation of all detection regions in the abnormal connected domain in the time sequence in the current period.

[0298] An abnormal sub-feature matrix is constructed based on the feature vector of each abnormal connected domain and the corresponding abnormal connected domain. The dimension of the abnormal sub-feature matrix is n x 2, wherein n is the number of abnormal connected domains, and 2 is the number of feature vectors of each abnormal connected domain.

[0299] In the abnormal sub-feature matrix, each row corresponds to a feature vector of an abnormal connected domain, and the form is wherein k represents the kth abnormal connected domain, and k is a natural number from 1 to n; the first column corresponds to the average attenuation deviation of all abnormal connected domains, that is, ; the second column corresponds to the attenuation fluctuation coefficient of all abnormal connected domains, that is, .

[0300] S455, obtaining the calibration parameter of each abnormal connected domain based on the abnormal sub-feature matrix;

[0301] Specifically, the present application mainly adopts a multiple linear regression model or a machine learning regression model (such as a random forest regression) to fit the relationship between each abnormal connected domain and the initial measured solid content deviation in the abnormal feature matrix, and to obtain the calibration parameter of each abnormal connected domain.

[0302] Exemplarily, the method of fitting by using a multiple linear regression model includes:

[0303] The calibration parameter formula corresponding to each abnormal connected domain is established, wherein the expression of the calibration parameter formula is:

[0304]

[0305] wherein, represents the calibration parameter of the abnormal connected domain; represents the basic calibration offset, reflecting the inherent error of the system; represents the weight of the average attenuation deviation; represents the weight of the attenuation fluctuation coefficient.

[0306] It should be noted that, , , Calibrated by historical experimental data. Specifically, prepare slurry samples with different solid contents (known standard values), collect multi-period attenuation data; extract the historical data and Multi-element regression fitting with known solid content deviation, solving , , .

[0307] S456, based on the calibration parameters of each abnormal connected domain, correct the predicted solid content of the battery slurry to be measured to obtain the actual solid content of the battery slurry to be measured;

[0308] Wherein, the embodiment mainly corrects the predicted solid content of the battery slurry to be measured based on the calibration parameters of each abnormal connected domain to obtain the actual solid content of the battery slurry to be measured, and the corresponding correction formula is:

[0309]

[0310] Wherein, represents the actual solid content; represents the predicted solid content; represents the calibration parameter of the kth abnormal connected domain; represents the proportion of the kth abnormal connected domain.

[0311] It can be understood that, that is, the predicted solid content obtained in S120.

[0312] It should be noted that the application of the multiple linear regression model to fit the relationship between the data is prior art, which will not be described here.

[0313] S600, obtaining a detection result according to the change of the actual solid content;

[0314] Wherein, the detection result is used to combine the actual solid content in time and space distribution changes, and reflects whether the battery slurry to be measured has abnormal defects such as bubbles, agglomeration, uneven dispersion, etc. In the present embodiment, the detection result of the battery slurry to be measured can be achieved by the following analysis:

[0315] S610, time series analysis is performed on a plurality of actual solid contents obtained within a period of time to obtain the solid content change;

[0316] Wherein, the time series analysis includes:

[0317] S611, trend judgment;

[0318] If the actual solid content presents stable fluctuations, and the fluctuation range is within the error range allowed by the process (such as ±0.5%), it can be preliminarily judged that the solid content of the battery slurry to be measured is in a normal controllable state; if the solid content presents a sustained upward or downward trend, or the fluctuation amplitude exceeds the threshold value, it indicates that there may be abnormalities in the slurry production process, such as uneven stirring, improper addition of raw materials, etc.

[0319] S612, rate of change calculation;

[0320] By calculating the solid content change rate (such as wherein, is the actual solid content at time t, is the actual solid content at time t-1) of adjacent time points, the change of the solid content is quantified; too large change rate may mean that the battery slurry transmission pipeline is blocked or the ultrasonic probe device suddenly fails or the process parameters such as temperature and flow suddenly change.

[0321] S620, spatial sequence analysis is performed on the multiple two-dimensional attenuation distribution matrices obtained by multiple annular probe units at the same time to obtain the solid content distribution;

[0322] The spatial sequence analysis includes:

[0323] S621, extracting the features of each two-dimensional attenuation distribution matrix:

[0324] The regional attenuation coefficient mean μ and the regional attenuation coefficient variance σ of each two-dimensional attenuation distribution matrix are calculated respectively 2 and the regional attenuation coefficient distribution range; wherein, the regional attenuation coefficient mean is used to reflect the overall attenuation level of the slurry, and indirectly reflects the mean solid content; the regional attenuation coefficient variance is used to measure the dispersion degree of the attenuation coefficient, and the larger the variance, the more uneven the solid content distribution in the slurry; the regional attenuation coefficient distribution range reflects the local extreme situation;

[0325] S622, positioning the abnormal detection area in each two-dimensional attenuation distribution matrix:

[0326] An abnormal threshold is set, and exemplarily, μ+kσ (usually k is 2 or 3) is set as the regional attenuation coefficient threshold, and the detection area with a regional attenuation coefficient higher than the regional attenuation coefficient threshold is marked as an abnormal detection area. These abnormal detection areas may correspond to defects such as agglomeration and bubbles in the slurry, affecting the performance of the battery.

[0327] S623, spatial distribution pattern recognition:

[0328] By comparing the multiple two-dimensional attenuation distribution matrices, the spatial distribution law of the abnormal detection area is analyzed. If the abnormal detection area is concentrated in the same position in different two-dimensional attenuation distribution matrices, it indicates that there is a persistent defect at the position. If the abnormal detection area is randomly distributed, it indicates that it may be caused by temporary interference factors.

[0329] In S630, the solid content change and the solid content distribution are associated and analyzed to obtain a detection result.

[0330] If the solid content continuously increases in the time sequence, and the attenuation coefficients of multiple detection areas in the two-dimensional attenuation distribution matrix increase, it can be inferred that the local solid particle concentration in the slurry is too high, and there is a risk of agglomeration.

[0331] It should be particularly noted that the ultrasonic detection processing device can locate the problem occurrence link according to the position of the abnormal area in the two-dimensional attenuation distribution matrix combined with the solid content change trend. For example, in a pipeline slurry transmission system, if the attenuation abnormality of the edge detection area in the two-dimensional attenuation distribution matrix continuously occurs, and the solid content fluctuation increases, it may be that the slurry is deposited or blocked in the inner wall of the pipeline. If the solid content suddenly decreases, and the attenuation coefficient of the center area of the matrix suddenly decreases, it may be that the slurry ratio is unbalanced (the proportion of the solvent increases).

[0332] Based on the same inventive concept, the embodiment of the present application also discloses an ultrasonic detection processing device. The ultrasonic detection processing device comprises a memory and a processor. The memory stores at least one instruction, at least one program, a code set or an instruction set. The at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to realize the ultrasonic detection method of the battery slurry solid content provided by the above method embodiment.

[0333] Based on the same inventive concept, the embodiment of the present application also discloses a computer readable storage medium. The storage medium stores at least one instruction, at least one program, a code set or an instruction set. The at least one instruction, at least one program, code set or instruction set can be loaded and executed by a processor to realize the ultrasonic detection method of the battery slurry solid content provided by the above method embodiment.

[0334] A person of ordinary skill in the art can understand that all or part of the steps of the above-mentioned embodiments can be completed by hardware, or by a program instructing related hardware, and the program can be stored in a computer readable storage medium, such as a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various storage medium capable of storing program codes.

Claims

1. A method for ultrasonic detection of solid content of battery slurry, characterized in that: include: Performing a first ultrasonic test on the battery slurry to be tested in the transmission pipeline to obtain ultrasonic transmission information, and obtaining a predicted solid content based on the ultrasonic transmission information and a preset standard working curve; When the battery slurry to be tested is a standard battery slurry with an unknown solid content, the predicted solid content is directly used as the actual solid content; Otherwise, determining whether to trigger a solid content calibration mechanism according to the predicted solid content; If the judgment is yes, calibrating the predicted solid content by the solid content calibration mechanism to obtain the actual solid content; Obtaining a test result according to the change in the actual solid content; The solid content calibration mechanism includes: Dividing the cross section of the transmission pipeline corresponding to the ultrasonic detection portion into a plurality of detection areas; Performing a third ultrasonic test on the battery slurry to be tested to obtain a regional attenuation coefficient corresponding to each of the test areas; generating a two-dimensional attenuation distribution matrix based on all the regional attenuation coefficients and the corresponding detection areas; According to the two-dimensional attenuation distribution matrix under a plurality of consecutive second detection cycles, stacking matrices along the time dimension to form a three-dimensional attenuation distribution matrix; Calibration parameters are obtained based on the three-dimensional attenuation distribution matrix, and the calibration parameters are used to perform fitting correction on the deviation of the predicted solid content.

2. The ultrasonic detection method for solid content of battery slurry according to claim 1, characterized in that: The first ultrasonic detection is achieved by using two transceiver probes in any one of the annular probe units mounted on the transmission pipe and symmetrically distributed 180° along the circumference of the transmission pipe, wherein one transceiver probe serves as a transmitting end to transmit ultrasonic waves to the battery slurry to be tested, and the other transceiver probe serves as a receiving end to receive ultrasonic waves that pass through the battery slurry to obtain ultrasonic transmission information.

3. The ultrasonic detection method for solid content of battery slurry according to claim 2, characterized in that: The third ultrasonic detection is achieved by using a plurality of transceiver probes uniformly distributed along the circumference of the transmission pipe in at least one of the annular probe units sleeved on the transmission pipe, wherein one transceiver probe among every two transceiver probes in all the transceiver probes serves as a transmitting end to transmit ultrasonic waves to the battery slurry to be tested, and the other transceiver probe serves as a receiving end to receive ultrasonic waves that pass through the battery slurry, and an ultrasonic transmission path is formed between every two transceiver probes; The performing of the third ultrasonic test on the battery slurry to be tested to obtain the regional attenuation coefficient corresponding to each of the detection areas includes: Perform ultrasonic testing on the battery slurry to be tested according to a preset path rotation rule to obtain a received signal amplitude corresponding to each ultrasonic transmission path, wherein the path rotation rule is used to form different ultrasonic transmission paths by orderly switching every two transceiver probes as a combination of a transmitting end or a receiving end; A regional attenuation coefficient corresponding to each of the detection areas is obtained according to all the received signal amplitudes.

4. The ultrasonic detection method for solid content of battery slurry according to claim 3, characterized in that: The ultrasonic detection of the battery slurry to be tested is performed according to the preset path rotation rule, and obtaining the received signal amplitude corresponding to each ultrasonic transmission path specifically includes: Selecting a transceiver probe as a transmitter in sequence, and generating a corresponding ultrasonic transceiver round after each selection of the transmitter, wherein each transceiver probe has one and only one opportunity to serve as a transmitter in each ultrasonic transceiver round; After each ultrasonic transceiver round is obtained, a transceiver probe other than the current transmitting end is selected in sequence as a receiving end, and after each receiving end is selected, a sub-round of the current ultrasonic transceiver round is generated; In each of the sub-rounds, an ultrasonic transmission test is performed based on the ultrasonic transmission paths corresponding to the current transmitting end and the current receiving end to obtain the amplitude of the received signal corresponding to each of the ultrasonic transmission paths.

5. The ultrasonic detection method for solid content of battery slurry according to claim 3, characterized in that: Each of the ultrasonic transmission paths passes through one or more of the detection areas, and each of the ultrasonic transmission paths corresponds to a regional attenuation coefficient corresponding to each of the detection areas passed through; and obtaining the regional attenuation coefficient corresponding to each of the detection areas according to all of the received signal amplitudes includes: Determining an objective function formula corresponding to each of the ultrasonic transmission paths to obtain a plurality of linear equations, wherein the objective function formula is used to reflect a quantitative relationship between a preset transmit signal amplitude, a received signal amplitude, and all corresponding regional attenuation coefficients in the ultrasonic transmission path, and each of the linear equations includes one or more regional attenuation coefficients; Determine an effective transmission path according to the ratio of each of the received signal amplitudes to the transmitted signal amplitudes, wherein the effective transmission path refers to an ultrasonic transmission path corresponding to the ratio of the received signal amplitude to the transmitted signal amplitude being within a preset ratio range; Substituting the received signal amplitude corresponding to each of the effective transmission paths and the preset transmitted signal amplitude into the corresponding linear equation to obtain a multivariate equation system consisting of all the linear equations; The regional attenuation coefficient corresponding to each of the detection areas is calculated according to the multivariate equation group.

6. The ultrasonic detection method for solid content of battery slurry according to claim 5, characterized in that: In each of the ultrasonic transmission paths, the attenuation law of the ultrasonic transmission signal satisfies the objective function formula, which is the following ultrasonic attenuation equation: ； in, is the amplitude of the transmitted signal, which is the preset value; is the received signal amplitude; is the set of detection areas corresponding to the kth ultrasonic transmission path; (i, j) is the corresponding position of each divided detection area in the coordinate system; is the regional attenuation coefficient corresponding to the detection area (i, j); is the propagation distance of the ultrasonic transmission signal in the detection area (i, j).

7. The ultrasonic detection method for solid content of battery slurry according to claim 6, characterized in that: Calculating the regional attenuation coefficient corresponding to each detection area according to the multivariate equation group includes: Obtaining a corresponding path-region propagation matrix according to the multivariate equation group, wherein the path-region propagation matrix is ​​a matrix form of the multivariate equation group; When the effective transmission path meets the preset direct solution conditions, the multivariate equations are solved by the least squares method to obtain the regional attenuation coefficient corresponding to each detection area, wherein the direct solution conditions include the minimum number of paths condition and the path distribution condition; When the effective transmission path does not satisfy the direct solution condition, the multivariate equation group is solved by iterative regularization to obtain the regional attenuation coefficient corresponding to each detection area.

8. The ultrasonic detection method for solid content of battery slurry according to claim 2, characterized in that: The determining whether to trigger the solid content calibration mechanism according to the predicted solid content includes: Performing a second ultrasonic test on the battery slurry to be tested, wherein the second ultrasonic test corresponds to a plurality of annular probe units spaced apart along the transmission direction of the transmission pipeline. The second ultrasonic test is achieved by using two transceiver probes in different annular probe units, symmetrically distributed 180° along the circumference of the transmission pipeline, in consecutive different first test cycles. One transceiver probe serves as a transmitting end to transmit ultrasonic waves to the battery slurry to be tested, and the other transceiver probe serves as a receiving end to receive ultrasonic waves transmitted through the battery slurry. One first test cycle corresponds to one detection subunit, and ultrasonic transmission information corresponding to each detection subunit is obtained. Obtaining an ultrasound transmission attenuation coefficient corresponding to each detection subunit according to the ultrasound transmission information corresponding to each detection subunit; Obtaining multiple comparative solid contents of the battery slurry to be tested according to all the ultrasonic transmission attenuation coefficients and the standard working curve; Whether to trigger the solid content calibration mechanism is determined based on multiple comparative solid contents of the battery slurry to be tested.

9. An ultrasonic detection processing device, characterized in that: It includes a memory and a processor, wherein the memory stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement an ultrasonic detection method for the solid content of a battery slurry as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that The readable storage medium stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement an ultrasonic detection method for the solid content of a battery slurry as described in any one of claims 1 to 8.

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