Electrolyte residual amount measurement method and device, battery management system and cloud platform

Abstract

The application discloses an electrolyte residual amount measurement method and device, a battery management system and a cloud platform. Applied to the technical field of lithium batteries, the method comprises the following steps: obtaining the squeezed electrolyte quality of a to-be-measured battery cell and the quality of reference electrolyte which is homologous to the electrolyte in the to-be-measured battery cell; performing the same weight loss treatment operation on the reference electrolyte and the to-be-measured battery cell after the electrolyte is squeezed, and determining the quality after the treatment; determining the quality of the electrolyte attached to the to-be-measured battery cell based on the quality change ratio of the reference electrolyte before and after the weight loss treatment and the quality change of the to-be-measured battery cell; and determining the electrolyte residual amount according to the squeezed electrolyte quality and the attached electrolyte quality. The scheme reverses the attached electrolyte quality by taking the homologous reference electrolyte as a reference, solves the problem that the electrolyte residue is difficult to directly measure, and thus improves the accuracy of the electrolyte residual amount measurement.

Description

Technical Field

[0001] This invention relates to the field of lithium battery technology, specifically to a method, apparatus, battery management system, and cloud platform for measuring electrolyte remaining amount. Background Technology

[0002] During battery cycling, the internal electrolyte is gradually consumed due to side reactions. Therefore, the amount of electrolyte remaining directly affects the lithium-ion conductivity and the overall electrical performance of the battery. Thus, accurately measuring the remaining electrolyte level is crucial for analyzing battery degradation mechanisms and assessing its health and remaining lifespan.

[0003] In existing technologies, physical or chemical methods involving external solvents are typically used to detect the remaining amount of electrolyte inside a battery. For example, the cleaning method involves flushing the inside of the battery with a large amount of organic solvent, attempting to completely wash out the electrolyte and then calculating the difference in mass.

[0004] However, the internal structure of batteries is porous and complex, making it difficult to completely remove the electrolyte through cleaning methods, resulting in significant errors in measurement results. Therefore, how to accurately measure the remaining electrolyte level has become an urgent problem to be solved. Summary of the Invention

[0005] In view of this, the embodiments of the present invention aim to provide a method, apparatus, battery management system and cloud platform for measuring electrolyte remaining amount, so as to solve the problems in the prior art.

[0006] A first aspect of the present invention provides a method for measuring the remaining amount of electrolyte in a battery cell, comprising: Obtain the mass of the extruded electrolyte of the battery cell under test, and the mass of the reference electrolyte which is of the same origin as the electrolyte in the battery cell under test; The reference electrolyte and the cell under test after squeezing were subjected to the same weight loss treatment operation, and the mass of the reference electrolyte and the cell under test after undergoing the weight loss treatment operation were determined. Based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the cell under test before and after the weight loss treatment operation, the mass of electrolyte attached to the cell under test is determined. The remaining amount of electrolyte in the battery cell under test is determined based on the mass of the extruded electrolyte and the mass of electrolyte adhering to the battery cell under test.

[0007] A second aspect of the present invention provides a method for measuring the remaining amount of electrolyte in a battery, the battery comprising at least one cell, the method comprising: The battery is disassembled to obtain at least one bare cell; For each of the bare cells, perform the following steps: The bare battery cell is subjected to an extrusion process to obtain the mass of extrudable electrolyte corresponding to the bare battery cell; A portion of the electrolyte extruded from the bare battery cell is used as a reference electrolyte that is of the same origin as the electrolyte inside the bare battery cell. The reference electrolyte and the bare battery cell after extrusion are subjected to the same weight loss treatment operation. Based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the bare cell before and after the weight loss treatment operation, the mass of electrolyte attached to the bare cell is determined. Based on the mass of the extrudable electrolyte and the mass of the electrolyte attached to the bare cell, the remaining amount of electrolyte in the bare cell is determined. The remaining electrolyte amount of the battery is determined based on the remaining electrolyte amount corresponding to each bare cell.

[0008] A third aspect of the present invention provides a cloud platform on which a trained electrolyte remaining quantity measurement model is deployed, wherein: The cloud platform is used to acquire the operating parameters of the battery or cell in real time, and input the operating parameters into the electrolyte remaining amount measurement model to estimate the electrolyte remaining amount of the battery or cell output by the electrolyte remaining amount measurement model.

[0009] A fourth aspect of the present invention provides a battery management system, the battery management system being electrically connected to a battery or a battery cell, wherein a trained electrolyte remaining quantity measurement model is deployed on the battery management system, wherein: The battery management system is used to acquire the operating parameters of the battery or cell in real time, and input the operating parameters into the electrolyte remaining amount measurement model to estimate the electrolyte remaining amount of the battery or cell output by the electrolyte remaining amount measurement model.

[0010] A fifth aspect of the present invention provides a battery cell electrolyte remaining quantity measuring device, comprising: The acquisition module is used to acquire the mass of the extruded electrolyte of the battery cell under test, and the mass of the reference electrolyte which is of the same origin as the electrolyte in the battery cell under test; The processing module is used to perform the same weight loss treatment operation on the reference electrolyte and the cell under test after squeezing, and to determine the mass of the reference electrolyte and the cell under test after undergoing the weight loss treatment operation respectively; The measurement module is used to determine the mass of electrolyte attached to the battery cell under test based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the battery cell under test before and after the weight loss treatment operation. The calculation module is used to determine the remaining amount of electrolyte in the battery cell under test based on the mass of the extruded electrolyte and the mass of electrolyte adhering to the battery cell under test.

[0011] This application provides a method for measuring the remaining electrolyte in a battery cell. By acquiring a reference electrolyte from the same source as the electrolyte in the battery cell under test, and subjecting this reference electrolyte to the same weight loss treatment as the cell after electrolyte removal, the mass of the electrolyte adhering to the cell is inferred from the clearly defined mass change ratio of the reference electrolyte under these conditions. This method indirectly measures the mass of the difficult-to-separate adhering electrolyte in the battery cell, overcoming the measurement errors caused by the inability to separately weigh the adhering electrolyte in traditional methods. It effectively improves the overall accuracy of measuring the remaining electrolyte in the battery cell, providing a more reliable data foundation for assessing battery health. Attached Figure Description

[0012] Figure 1 This is a flowchart illustrating a method for measuring the remaining amount of electrolyte in a battery cell, provided in an embodiment of this application.

[0013] Figure 2 This is a flowchart illustrating a method for measuring the remaining amount of battery electrolyte provided in an embodiment of this application.

[0014] Figure 3 This is a schematic diagram illustrating a measurement accuracy provided in this application specification.

[0015] Figure 4 This is a schematic diagram of a battery cell electrolyte remaining quantity measuring device provided in this specification.

[0016] Figure 5 This application provides a battery electrolyte remaining amount measuring device.

[0017] Figure 6 This is a schematic diagram of the architecture of an electronic device provided in an embodiment of this application. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0020] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0021] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0022] During battery cycling, the internal electrolyte is gradually consumed due to side reactions. When the electrolyte consumption reaches a certain level, insufficient remaining electrolyte leads to decreased lithium-ion conductivity, increased internal resistance, and a significant decline in battery performance. Therefore, it is necessary to analyze the remaining electrolyte level to assess the battery's health and avoid performance degradation caused by insufficient electrolyte. Thus, accurate measurement of the remaining electrolyte level is crucial for analyzing battery degradation mechanisms and assessing its health and remaining lifespan.

[0023] Existing testing methods mostly use organic solvents as cleaning or extraction solvents, and are primarily applied to soft-pack testing. However, for large-capacity batteries with porous and complex cell structures, some electrolyte remains in the pores, and the solvent and electrolyte cannot mix uniformly, resulting in significant errors in the results.

[0024] For example, a common method for measuring the remaining electrolyte is the cleaning method. This involves using a solvent to clean the battery and remove the remaining electrolyte. After drying, the difference between the battery's weight before and after cleaning is used to determine the remaining electrolyte. However, this method consumes a large amount of organic solvent, and the complex material structure inside the large battery cell makes it difficult to completely remove the electrolyte, resulting in significant measurement errors.

[0025] Another method for measuring the remaining electrolyte amount involves using the internal standard method. This involves adding a known mass of internal standard solution to the electrolyte of the battery under test, mixing the internal standard solution with the electrolyte, and then measuring the concentration of the internal standard in the electrolyte. The remaining electrolyte amount can then be calculated using a formula. However, this method cannot achieve a perfectly uniform mixture between the internal standard solution and the electrolyte, and for large battery systems, achieving a uniform mixture is even more challenging, leading to significant measurement errors.

[0026] Alternatively, current methods also employ extraction to measure the remaining electrolyte amount. This involves adding an extractant to the battery under test to extract the electrolyte, and then measuring the remaining amount. However, the extractant suffers from drawbacks such as uneven distribution within the battery and a tendency to react with the electrolyte, leading to significant measurement errors. Therefore, this application proposes a method for measuring the remaining electrolyte amount in a battery cell. By utilizing a reference electrolyte of the same origin as the electrolyte within the battery, this reference electrolyte undergoes the same weight loss process as the component containing the electrolyte to be tested. By measuring the weight loss ratio of the reference electrolyte, the mass of the attached electrolyte can be inferred. This allows for accurate calibration of the mass of the difficult-to-separate attached electrolyte without introducing external solvents or addressing the problem of mixing uniformity. In other words, it provides a mass calibration method based on a homologous reference and synchronous weight loss, solving the technical problem of large measurement errors caused by the inability to directly and accurately weigh the electrolyte adhering to a porous solid framework.

[0027] like Figure 1 As shown, Figure 1 This is a flowchart illustrating a method for measuring the remaining electrolyte level in a battery cell, provided in an embodiment of this application. Specifically, it includes the following steps: Step S100: Obtain the mass of the extruded electrolyte of the battery cell under test, and the mass of the reference electrolyte which is from the same source as the electrolyte in the battery cell under test.

[0028] Since the electrolyte inside the battery cell exists in the pores of the electrode material and the separator and is tightly bonded to the solid skeleton, it is extremely difficult to directly separate and weigh it. Therefore, this application needs to obtain some key initial data first, namely: the mass of the extruded electrolyte squeezed out of the battery cell by physical methods, and the mass of the reference electrolyte as a reference benchmark for weight loss behavior, so as to obtain the mass of the attached electrolyte through indirect calculation later.

[0029] In one or more embodiments of this application, the entity executing the measurement method can be a laboratory technician, automated testing equipment, or a combination of both. That is, it supports both purely manual operation and fully automated execution, as well as a combination of semi-manual and semi-automatic methods. The specific method can be flexibly configured according to the actual application scenario, and this application does not impose any limitations on it. For ease of description, the execution end of the method will be used as the entity executing the operation in the following description. The execution end can be an operator, automated equipment, or a combination of both. This application does not impose any limitations on this.

[0030] Specifically, the execution terminal acquires the mass of the extruded electrolyte from the cell under test and the mass of the reference electrolyte, which originates from the same source as the electrolyte inside the cell under test. In one or more embodiments of this application, the specific method by which the execution terminal acquires the mass of the extruded electrolyte and the reference electrolyte is not limited. It can be determined based on manually input data, or by accessing specific storage, or by determining the mass of the bare cell under test, then performing an extrusion operation on the cell under test, and determining the mass of the cell under test after extrusion. Based on the mass of the bare cell and the mass after extrusion, the mass of the extruded electrolyte from the cell under test is determined. The cell under test can be a complete cell removed separately from a battery pack or battery assembly, or it can refer to a bare cell removed from the battery casing after preliminary disassembly. This application does not impose any restrictions and can be set according to actual needs.

[0031] Furthermore, the reference electrolyte refers to any electrolyte sample that is the same as or highly consistent in composition with the electrolyte in the battery under test, and is used to calibrate the proportion of mass loss under the same weight loss conditions. Specifically, it can refer to a portion of the electrolyte squeezed out from the battery under test itself, or it can cover the use of a spare electrolyte prepared in the same batch as when the battery was filled.

[0032] Furthermore, when determining the reference electrolyte, in order to make subsequent measurement results more accurate, the reference electrolyte is generally a portion of the extruded electrolyte.

[0033] Step S102: Perform the same weight loss treatment on the reference electrolyte and the cell under test after squeezing, and determine the mass of the reference electrolyte and the cell under test after the weight loss treatment.

[0034] Since the evaporation weight loss rate of electrolyte under conditions such as heating or depressurization is closely related to its composition and external environment, after obtaining the mass of extruded electrolyte and reference electrolyte, the same weight loss operation can be performed on the reference electrolyte and the cell under test after extrusion to establish the weight loss correlation between the two under the same conditions, so as to subsequently infer the mass of electrolyte adhering to the cell under test.

[0035] It should be noted that, in one or more embodiments of this application, the weight loss treatment operation generally refers to a physical or chemical process that can cause volatile components in the electrolyte, such as carbonate solvents, to escape, thereby resulting in a reduction in total mass. For example, it may include, but is not limited to, drying treatment under constant or programmed constant temperature, vacuum evaporation treatment under negative pressure, evaporation treatment under inert gas purging, or a combination of these conditions.

[0036] Specifically, the weight loss treatment operation can be carried out by placing a weighing dish containing the reference electrolyte and the cell to be tested after squeezing the electrolyte into a pre-set oven, for example, the oven temperature is set to 80°C, and drying is continued until the mass change between two consecutive weighing intervals is less than 0.001g, which is considered to have reached constant weight. Then, both are taken out and cooled to room temperature in a dry environment. After that, the mass of the reference electrolyte and the mass of the cell to be tested are weighed separately using a precision electronic balance after the weight loss treatment operation.

[0037] Furthermore, weight loss treatment operations can also include vacuum evaporation, such as vacuum drying at a low temperature, such as 50°C, with the aid of a vacuum pump, or evaporation by purging with dry nitrogen or argon gas, thereby achieving weight loss treatment of the electrolyte.

[0038] Step S104: Based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the cell under test before and after the weight loss treatment operation, determine the mass of the electrolyte attached to the cell under test.

[0039] To address the issue of not being able to directly measure the initial mass of the electrolyte adhering to the battery cell, the mass of the solid portion of the battery cell originally adhering to the electrolyte lost during the same process can be determined by using the ratio of the mass change of the reference electrolyte before and after the weight loss treatment. Specifically, by comparing the mass difference of the reference electrolyte before and after weight loss to its initial mass, a weight loss ratio coefficient can be obtained. Applying this coefficient to the mass difference of the battery cell before and after the weight loss treatment after liquid extrusion, the initial mass of the electrolyte adhering to that mass difference can be deduced.

[0040] Specifically, the mass change ratio of the reference electrolyte before and after the weight loss treatment is: ( - ) / This ratio represents the rate of evaporation and weight loss of this electrolyte under specific weight loss conditions. The mass change of the test cell after liquid extrusion before and after the weight loss treatment is: ( - It is important to understand that the battery cell loses mass during the drying process after liquid extraction. - This is entirely due to the evaporation of the adhering electrolyte that remains inside and cannot be squeezed out. Assume the initial mass of this adhering electrolyte is... Then, the mass loss after undergoing the same weightlessness treatment should be: ×[( - ) / This mass loss value is exactly equal to the measured decrease in cell mass. - Therefore, an equation can be established: ×[( - ) / ] = ( - Therefore, the mass of electrolyte adhering to the battery cell under test can be determined. = ( - ) / [( - ) / ] = ( - )× / ( - ).

[0041] Step S106: Determine the remaining amount of electrolyte in the battery cell under test based on the mass of the extruded electrolyte and the mass of electrolyte adhering to the battery cell under test.

[0042] Finally, after determining the mass of electrolyte adhering to the cell under test, the remaining amount of electrolyte in the cell can be determined based on the mass of extruded electrolyte, which is the sum of the mass of extruded electrolyte and the mass of electrolyte adhering to the cell under test. = + .

[0043] based on Figure 1 A method for measuring the remaining electrolyte in a battery cell is proposed. This method obtains a reference electrolyte from the same source as the electrolyte in the cell under test, and subjectes this reference electrolyte to the same weight loss treatment as the cell after electrolyte removal. Based on the clearly defined mass change ratio of the reference electrolyte under these conditions, the mass of the electrolyte adhering to the cell is inferred. This method achieves indirect measurement of the mass of the difficult-to-separate adhering electrolyte in the cell, overcoming the measurement errors caused by the inability to separately weigh the adhering electrolyte in traditional methods. It effectively improves the overall accuracy of measuring the remaining electrolyte in the cell, providing a more reliable data foundation for assessing battery health.

[0044] Furthermore, since the electrolyte remaining amount measurement method disclosed in this application is also applicable to complete battery systems, this application also provides a battery electrolyte remaining amount measurement method, such as... Figure 2 As shown,Figure 2 This is a flowchart illustrating a method for measuring the remaining amount of battery electrolyte provided in an embodiment of this application.

[0045] Step S200: Disassemble the battery to obtain at least one bare cell. For each bare cell, perform the following steps: It should be noted that the battery includes at least one cell. Therefore, when measuring the remaining electrolyte in the battery, the battery can be disassembled to obtain at least one bare cell, thereby dividing the complete battery system into multiple independently measurable units.

[0046] Specifically, for square aluminum or plastic-cased batteries, the casing can be cut open using a special tool in an argon-filled glove box to remove the internal wound or stacked cell assembly.

[0047] Step S202: Perform a liquid extrusion process on the bare battery cell to obtain the mass of extrudable electrolyte corresponding to the bare battery cell.

[0048] Step S204: Obtain a portion of the electrolyte extruded from the bare cell as a reference electrolyte that is homologous to the electrolyte inside the bare cell.

[0049] Step S206: The reference electrolyte and the bare battery cell after squeezing are subjected to the same weight loss treatment operation.

[0050] Step S208: Based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the bare cell before and after the weight loss treatment operation, determine the mass of the electrolyte attached to the bare cell.

[0051] Step S210: Based on the mass of the extrudable electrolyte and the mass of the electrolyte attached to the bare cell, determine the remaining amount of electrolyte in the bare cell.

[0052] Steps S202 to S210 can be referred to the description of steps S100 to S106 above, and will not be repeated here. It should be noted that if free electrolyte is obtained during the battery disassembly process, the reference electrolyte can also be extracted from the free electrolyte when determining the reference electrolyte.

[0053] Step S212: Determine the remaining electrolyte amount of the battery based on the remaining electrolyte amount corresponding to each bare cell.

[0054] After determining the remaining electrolyte amount for each bare cell in the battery, the remaining electrolyte amounts for all bare cells are added together to obtain the total remaining electrolyte amount for the battery. Additionally, when there is more than one battery, the remaining electrolyte amount for the battery pack can be determined based on the connection relationships between the cells. For example, for series-connected batteries, the remaining electrolyte amount for the battery pack can be the sum of the remaining electrolyte amounts for each cell; for parallel-connected batteries, if the cell characteristics are consistent, an average value or a weighted sum can be used.

[0055] Furthermore, if unabsorbed free electrolyte is found inside the battery during disassembly, the free electrolyte can be collected first to determine its mass in order to ensure that the measurement results cover all forms of electrolyte present in the battery.

[0056] Specifically, when disassembling the battery, first open the battery casing in a safe environment. Collect the free electrolyte that has been poured out or drawn from the casing but has not yet penetrated the battery cells, and weigh it using a precision balance. Record its mass as follows: Then, when calculating the remaining electrolyte level of the battery, after determining the remaining electrolyte level for each cell, this is added to the remaining electrolyte level. More accurate measurements of the remaining electrolyte level have been obtained.

[0057] In addition, because the shell itself also has structures such as gaps, the measurements obtained... The amount of electrolyte remaining is relatively small compared to the true value, and some free electrolyte remains. Therefore, to obtain a more accurate measurement of the remaining electrolyte, the obvious electrolyte droplets on the surface of the battery casing after removing each bare cell can be removed, but the portion wetted on the microscopic rough surface inside the casing can be retained. This portion can be weighed and recorded as the first casing mass. Perform the same weightlessness treatment on the shell. For example, weigh... The casing was placed in an oven and dried together with the reference electrolyte and the squeezed-out battery cell. After drying, the mass of the casing after the weightlessness treatment was obtained. Next, based on the mass change ratio of the reference electrolyte and the mass change between the first and second casings, the mass of the electrolyte adhering to the casing is determined. The calculation principle is the same as that for electrolyte adhering to the battery cell: the mass reduction of the casing during the drying process (… - The amount of electrolyte adhering to the casing was determined to be entirely due to evaporation from the electrolyte on its surface. Therefore, the mass of the electrolyte adhering to the casing... = ( - ) / [( - ) / ] = ( - )× / ( - ).

[0058] Then, calculate , The remaining electrolyte amount of the battery is determined by summing the remaining electrolyte amounts of each cell.

[0059] Since the above-mentioned measurement method involves measuring the remaining electrolyte after damaging the battery or cell, to improve measurement efficiency and meet the requirement of non-destructive testing, in one or more embodiments of this application, the operating parameters of the cell or battery under test can be determined before the step of obtaining the mass of the extruded electrolyte. These operating parameters may include at least two of the following: charge / discharge cycle count, state of health, voltage, current, and internal resistance. For example, before disassembling the battery, it can be placed on a standard charge / discharge testing device, its discharge capacity at rated capacity can be recorded to calculate its state of health, its cycle count log can be recorded, and its AC internal resistance at 50% charge can be measured. The measured remaining electrolyte amount can be used as a label for the operating parameters to construct a training sample.

[0060] Specifically, multiple battery samples of the same model but at different cycle stages, such as 0, 100, and 500 cycles, can be collected. The aforementioned complete destructive measurement method is performed on each sample to obtain its precise remaining electrolyte level. Simultaneously, a set of operating parameters measured before disassembly of each sample is recorded, such as the number of cycles N, state of health (SOH), and internal resistance R. Each battery sample constitutes a training sample, with a feature vector of [N, SOH, R] and a label of the precisely measured remaining electrolyte level. These training samples are used to train the electrolyte remaining level measurement model. This model can be a linear regression model, support vector machine, neural network, or other machine learning model (this application does not limit this). Through training, the model learns the complex mapping relationship between operating parameters and the remaining electrolyte level.

[0061] Furthermore, based on the trained model described above, this disclosure also provides two specific application system embodiments. Specifically, this application also provides a cloud platform on which the trained electrolyte remaining quantity measurement model is deployed. This cloud platform can connect to a remote battery management system or data acquisition device via an IoT interface to acquire the operating parameters of the battery or cell in real time. The operating parameters are then input into the electrolyte remaining quantity measurement model, which outputs a predicted result of the remaining electrolyte quantity of the battery or cell. This result can be returned to the user terminal for display or used for subsequent health status analysis.

[0062] Furthermore, this electrolyte remaining quantity measurement model can also be deployed on a battery management system (BMS) electrically connected to the battery or cell. The BMS has the trained electrolyte remaining quantity measurement model deployed on its internal memory or processor. The BMS can acquire real-time operating parameters of the managed batteries or cells, such as real-time current and voltage, estimated internal resistance, and recorded cycle count, through its sensors and communication modules. Then, the BMS locally inputs these operating parameters into the electrolyte remaining quantity measurement model to directly estimate the remaining electrolyte quantity. This result can be used locally for battery status alerts, optimizing charging strategies, or reporting to the upper-level controller. Edge computing improves the speed of electrolyte remaining quantity measurement without relying on a continuous network connection.

[0063] like Figure 3 As shown, Figure 3 This diagram illustrates a measurement accuracy method provided in this application. In a verification experiment, for a pouch battery sample with a known electrolyte injection volume of 11.806 grams, the electrolyte volume calculated using this method was 11.546 grams, with an error of 2.2%. For another pouch sample with an injection volume of 13.591 grams, the measured volume was 13.425 grams, with an error of 1.2%. For a large prismatic battery with an injection volume of 476.40 grams, the measured volume was 472.56 grams, with an error of only 0.81%; for another sample with an injection volume of 477.60 grams, the measured volume was 474.72 grams, with an error of 0.60%. The electrolyte remaining amount measurement method provided in this application uses a direct drying method, which calculates the remaining electrolyte amount based on the principle that the reference electrolyte and the cell electrolyte have the same evaporation rate during drying. This method has a smaller experimental error, does not use solvents, and avoids the experimental errors caused by large solvent usage and incomplete cleaning in washing methods, as well as uneven solvent distribution in internal standard and extraction methods. It can be used to test the remaining electrolyte amount of different types of batteries, including both pouch and hard-shell large batteries. Furthermore, the experimental error does not increase when applied to large battery systems, solving the problem that internal standard and extraction methods are only suitable for pouch batteries and have larger results in large batteries. Moreover, the method provided in this application can obtain the remaining electrolyte amount of batteries in different states, such as fresh batteries and batteries with different cycle counts. This provides a rich training sample for determining the remaining electrolyte amount of batteries without disassembling them.

[0064] Furthermore, the application scenarios of the above-described method for measuring the remaining electrolyte amount are not limited in one or more embodiments of this application. For example, in the root cause analysis of battery failure, during battery research and development or quality assurance analysis, when a batch of batteries exhibits abnormal capacity decay or a sudden increase in internal resistance, it is necessary to determine the main cause of failure. Related technologies typically analyze this by disassembling and observing or detecting changes in electrode materials, but it is difficult to quantify the role played by electrolyte consumption. Using this method, the remaining electrolyte amount of failed batteries and normal control batteries can be accurately measured. By comparing the data of the two, if it can be clearly measured that the remaining electrolyte amount of the failed battery is significantly lower than that of the normal battery, while the loss of electrode active material is comparable, then the performance degradation can be directly attributed to excessive electrolyte consumption, avoiding the misallocation of resources to ineffective optimization of electrode materials.

[0065] Alternatively, real-time monitoring of the remaining electrolyte level in operating batteries can be used to achieve online health monitoring and early warning of the battery system. In battery systems operating for extended periods, such as electric vehicles and energy storage power stations, the gradual consumption of electrolyte is one of the key intrinsic factors contributing to performance degradation, but existing battery management systems typically cannot directly monitor this parameter. When electrolyte consumption accumulates to a critical level, the battery may face a tipping point where its power capacity drops sharply or the risk of thermal runaway increases. To issue early warnings before irreversible performance degradation occurs, an online monitoring and evaluation system can be built based on this method. When the estimated value falls below a safety threshold set based on experimental data, or when the consumption rate accelerates abnormally, the system can issue a maintenance or replacement warning in advance, thereby avoiding sudden failures caused by electrolyte depletion.

[0066] Specifically, after determining the remaining electrolyte level of the battery, the battery's health status can be determined based on the remaining electrolyte level. Then, when the battery's health status exceeds the threshold, a safety warning is issued to provide early warning for maintenance or replacement, thereby avoiding sudden failures caused by electrolyte depletion.

[0067] Of course, in one or more embodiments of this application, the specific method used to determine the battery's health status is not limited. For example, multiple electrolyte balance ranges can be preset, each range corresponding to a health level. The battery's health level is determined based on the range into which the battery's electrolyte balance falls. Alternatively, the battery's operating data can be acquired, and the battery's health status can be evaluated based on the operating data and the battery's electrolyte balance. Since there are many methods for determining battery health status, this application does not list them all; the method can be set according to actual needs.

[0068] Of course, the methods described above in this application can also be applied to other fields, which are not listed here. They can be set according to actual needs, and this application does not impose any restrictions on them.

[0069] Figure 4 This is a schematic diagram of a battery cell electrolyte remaining quantity measuring device provided in this specification, wherein: The acquisition module 400 is used to acquire the mass of the extruded electrolyte of the battery cell under test, and the mass of the reference electrolyte which is of the same origin as the electrolyte in the battery cell under test; The processing module 401 is used to perform the same weight loss treatment operation on the reference electrolyte and the cell under test after squeezing, and to determine the mass of the reference electrolyte and the cell under test after undergoing the weight loss treatment operation respectively. Measurement module 402 is used to determine the mass of electrolyte attached to the battery cell under test based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the battery cell under test before and after the weight loss treatment operation. The calculation module 403 is used to determine the remaining amount of electrolyte in the battery cell under test based on the mass of the extruded electrolyte and the mass of electrolyte adhering to the battery cell under test.

[0070] Optionally, the acquisition module 400 is used to determine the bare cell mass of the cell under test; perform a liquid extraction operation on the cell under test and determine the mass of the cell under test after liquid extraction; and determine the mass of the extruded electrolyte of the cell under test based on the bare cell mass and the mass after liquid extraction.

[0071] Optionally, the measurement module 402 is configured to: determine a cell mass difference based on the mass of the cell under test before the weight loss treatment operation and the mass of the cell under test after the weight loss treatment operation; determine a reference mass difference based on the mass of the reference electrolyte before the weight loss treatment operation and the mass of the reference electrolyte after the weight loss treatment operation; determine a weight loss ratio coefficient based on the ratio of the reference mass difference to the mass of the reference electrolyte before the weight loss treatment operation; and determine the mass of electrolyte adhering to the cell under test based on the ratio of the cell mass difference to the weight loss ratio coefficient.

[0072] Optionally, the acquisition module 400 is used to determine the operating parameters of the cell under test, wherein the operating parameters include at least two of the cell's charge-discharge cycle count, health status, voltage, current, and internal resistance; after the step of determining the remaining electrolyte amount of the cell under test, the method further includes: using the remaining electrolyte amount as a label for the operating parameters to construct training samples, wherein the training samples are used to train an electrolyte remaining amount measurement model.

[0073] like Figure 5 As shown, Figure 5 A battery electrolyte remaining amount measuring device provided in this application embodiment, the battery including at least one cell, comprising: The disassembly module 500 is used to disassemble the battery to obtain at least one bare cell; The battery cell electrolyte measurement module 501 is used to perform the following steps for each bare battery cell: extruding the bare battery cell to obtain the extrudable electrolyte mass corresponding to the bare battery cell; obtaining a portion of the extruded electrolyte from the bare battery cell as a reference electrolyte of the same origin as the electrolyte inside the bare battery cell; subjecting the reference electrolyte and the extruded bare battery cell to the same weight loss treatment operation; determining the electrolyte mass attached to the bare battery cell based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the bare battery cell before and after the weight loss treatment operation; and determining the remaining electrolyte amount of the bare battery cell based on the extrudable electrolyte mass and the electrolyte mass attached to the bare battery cell. The determining module 502 is used to determine the remaining electrolyte of the battery based on the remaining electrolyte of each bare cell.

[0074] Optionally, during the disassembly process, the battery contains free electrolyte; the disassembly module 500 is used to disassemble the battery to obtain at least one bare cell and the mass of the free electrolyte.

[0075] Optionally, the device further includes a casing electrolyte measurement module 503, used to determine a first casing mass of the casing, perform the weightlessness treatment operation on the casing; obtain a second casing mass of the casing after undergoing the weightlessness treatment operation; determine the mass of the attached electrolyte on the casing based on the mass difference between the first casing mass and the second casing mass, and the mass change ratio of the reference electrolyte before and after the weightlessness treatment operation; the determining module 502 is used to determine the remaining electrolyte of the battery based on the sum of the remaining electrolyte amount corresponding to each bare cell, the mass of the free electrolyte, and the mass of the attached electrolyte on the casing.

[0076] Optionally, the casing electrolyte measurement module 503 is configured to: determine a casing mass difference based on the difference between the mass of the first casing and the mass of the second casing; determine a reference mass difference based on the mass of the reference electrolyte before the weight loss treatment operation and the mass of the reference electrolyte after the weight loss treatment operation; determine a weight loss ratio coefficient based on the ratio of the reference mass difference to the mass of the reference electrolyte before the weight loss treatment operation; and determine the mass of the electrolyte adhering to the casing based on the ratio of the casing mass difference to the weight loss ratio coefficient.

[0077] Optionally, the device further includes a training module 504 for determining the operating parameters of the battery, wherein the operating parameters include at least two of the following: the number of charge-discharge cycles, health status, voltage, current, and internal resistance of the battery; and constructing training samples by using the remaining electrolyte level of the battery as a label for the operating parameters of the battery, wherein the training samples are used to train the electrolyte remaining level measurement model.

[0078] Optionally, the device further includes an early warning module 505, used to determine the health status of the battery based on the determined remaining electrolyte level; and to issue a safety warning when the health status of the battery exceeds a threshold.

[0079] It should be noted that the above-described embodiments are merely illustrative. For example, the division of the units is only a logical functional division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0080] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for apparatus or device embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The professional and apparatus embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0081] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0082] This application also provides a computer storage medium for storing a computer program that, when executed by a processor, implements the steps of any one of the methods described in the foregoing method embodiments.

[0083] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in any of the foregoing method embodiments.

[0084] in, Figure 6 An exemplary architecture of an electronic device is illustrated. This electronic device is used to perform the aforementioned method for measuring the remaining amount of a battery cell or electrolyte. The electronic device can be installed in a battery management system or a cloud platform to perform this method. Specifically, it may include a processor 610, a video display adapter 611, a disk drive 612, an input / output interface 613, a network interface 614, and a memory 620. The processor 610, video display adapter 611, disk drive 612, input / output interface 613, network interface 614, and memory 620 can communicate with each other via a communication bus 630.

[0085] The processor 610 can be implemented using a general-purpose CPU, microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits to execute relevant programs and implement the technical solution provided in this application.

[0086] The memory 620 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 620 can store the operating system 5621 for controlling the operation of the electronic device 600, and the basic input / output system (BIOS) 622 for controlling the low-level operations of the electronic device 600. Additionally, it can store a web browser 623, a data storage management system 624, and a media file playback device 700, etc. The aforementioned media file playback device 700 can be the application program that specifically implements the aforementioned steps in this embodiment. In summary, when implementing the technical solution provided in this application through software or firmware, the relevant program code is stored in the memory 620 and is called and executed by the processor 610.

[0087] Input / output interface 613 is used to connect input / output modules to realize information input and output. Input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, speakers, vibrators, indicator lights, etc.

[0088] Network interface 614 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0089] Bus 630 includes a pathway for transmitting information between various components of the device, such as processor 610, video display adapter 611, disk drive 612, input / output interface 613, network interface 614, and memory 620.

[0090] It should be noted that although the above-described device only shows the processor 610, video display adapter 611, disk drive 612, input / output interface 613, network interface 614, memory 620, bus 630, etc., in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the solution of this application, and does not necessarily include all the components shown in the figures.

[0091] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer program product. This computer program product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for measuring the remaining electrolyte in a battery cell, characterized in that, include: Obtain the mass of the extruded electrolyte of the battery cell under test, and the mass of the reference electrolyte which is of the same origin as the electrolyte in the battery cell under test; The reference electrolyte and the cell under test after squeezing were subjected to the same weight loss treatment operation, and the mass of the reference electrolyte and the cell under test after undergoing the weight loss treatment operation were determined. Based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the cell under test before and after the weight loss treatment operation, the mass of electrolyte attached to the cell under test is determined. The remaining amount of electrolyte in the battery cell under test is determined based on the mass of the extruded electrolyte and the mass of electrolyte adhering to the battery cell under test.

2. The method for measuring the remaining electrolyte in a battery cell as described in claim 1, characterized in that, The step of obtaining the mass of the extruded electrolyte of the battery cell under test specifically includes: Determine the bare cell quality of the battery cell under test; Perform a liquid extraction operation on the battery cell under test, and determine the mass of the battery cell under test after liquid extraction; The mass of the extruded electrolyte in the battery cell to be tested is determined based on the mass of the bare battery cell and the mass after extrusion.

3. The method for measuring the remaining electrolyte in a battery cell as described in claim 1, characterized in that, The reference electrolyte is a portion of the extruded electrolyte.

4. The method for measuring the remaining electrolyte in a battery cell as described in claim 1, characterized in that, The weight loss treatment operation includes drying or vacuum evaporating the reference electrolyte and the cell under test after squeezing.

5. The method for measuring the remaining electrolyte in a battery cell as described in claim 1, characterized in that, The step of determining the mass of electrolyte adhering to the battery cell under test based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the battery cell under test before and after the weight loss treatment operation, specifically includes: The mass difference of the battery cell is determined based on the mass of the battery cell before the weightlessness treatment operation and the mass of the battery cell after the weightlessness treatment operation. The reference mass difference is determined based on the mass of the reference electrolyte before the weight loss treatment operation and the mass of the reference electrolyte after the weight loss treatment operation. The weight loss ratio coefficient is determined based on the ratio of the reference mass difference to the mass of the reference electrolyte before the weight loss treatment operation. The mass of electrolyte adhering to the battery cell under test is determined based on the ratio of the cell mass difference to the weight loss ratio coefficient.

6. The method for measuring the remaining electrolyte in a battery cell as described in claim 1, characterized in that, The method further includes the following steps prior to obtaining the mass of the extruded electrolyte from the battery cell under test: Determine the operating parameters of the battery cell under test, wherein the operating parameters include at least two of the following: the number of charge-discharge cycles, health status, voltage, current, and internal resistance of the battery cell; After the step of determining the remaining electrolyte amount of the battery cell under test, the method further includes: The remaining electrolyte level is used as a label for the operating parameter to construct a training sample, which is then used to train the electrolyte level measurement model.

7. A method for measuring the remaining amount of battery electrolyte, characterized in that, The battery includes at least one cell, and the method includes: The battery is disassembled to obtain at least one bare cell; For each of the bare cells, perform the following steps: The bare battery cell is subjected to an extrusion process to obtain the mass of extrudable electrolyte corresponding to the bare battery cell; A portion of the electrolyte extruded from the bare battery cell is used as a reference electrolyte that is of the same origin as the electrolyte inside the bare battery cell. The reference electrolyte and the bare battery cell after extrusion are subjected to the same weight loss treatment operation. Based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the bare cell before and after the weight loss treatment operation, the mass of electrolyte attached to the bare cell is determined. Based on the mass of the extrudable electrolyte and the mass of the electrolyte attached to the bare battery cell, the remaining amount of electrolyte in the bare battery cell is determined. The remaining electrolyte amount of the battery is determined based on the remaining electrolyte amount corresponding to each bare cell.

8. The method for measuring the remaining amount of battery electrolyte as described in claim 7, characterized in that, During the disassembly process, the battery contains free electrolyte. The step of disassembling the battery to obtain at least one bare cell specifically includes: The battery is disassembled to obtain at least one bare cell and the mass of the free electrolyte.

9. The method for measuring the remaining amount of battery electrolyte as described in claim 8, characterized in that, The method further includes: Determine the first housing mass of the battery housing, and perform the weightlessness treatment operation on the housing; Obtain the second shell mass after the weightlessness treatment operation; The mass of the electrolyte adhering to the shell is determined based on the mass difference between the first shell mass and the second shell mass, and the mass change ratio of the reference electrolyte before and after the weightlessness treatment operation. The step of determining the remaining electrolyte amount of the battery based on the remaining electrolyte amount corresponding to each bare cell specifically includes: The remaining electrolyte amount of the battery is determined based on the sum of the remaining electrolyte amount corresponding to each bare cell, the mass of the free electrolyte, and the mass of the electrolyte adhering to the casing.

10. The method for measuring the remaining amount of battery electrolyte as described in claim 9, characterized in that, The step of determining the mass of the electrolyte adhering to the shell based on the mass difference between the first shell mass and the second shell mass, and the proportion of the mass change of the reference electrolyte before and after the weightlessness treatment operation, specifically includes: The difference in shell mass is determined based on the difference between the mass of the first shell and the mass of the second shell. The reference mass difference is determined based on the mass of the reference electrolyte before the weight loss treatment operation and the mass of the reference electrolyte after the weight loss treatment operation. The weight loss ratio coefficient is determined based on the ratio of the reference mass difference to the mass of the reference electrolyte before the weight loss treatment operation. The mass of the electrolyte adhering to the shell is determined based on the ratio of the difference in shell mass to the weight loss ratio coefficient.

11. The method for measuring the remaining amount of battery electrolyte as described in claim 7, characterized in that, The method further includes: Determine the operating parameters of the battery, wherein the operating parameters include at least two of the following: the number of charge-discharge cycles, state of health, voltage, current, and internal resistance of the battery; After the step of determining the remaining electrolyte level of the battery, the method further includes: The remaining electrolyte level of the battery is used as a label for the battery's operating parameters to construct training samples, which are then used to train the electrolyte remaining level measurement model.

12. The method for measuring the remaining amount of battery electrolyte as described in any one of claims 7 to 11, characterized in that, The method further includes: The health status of the battery is determined based on the determined remaining electrolyte level. A safety warning is issued when the battery's health status exceeds a threshold.

13. A cloud platform, characterized in that, The cloud platform is equipped with a trained electrolyte remaining quantity measurement model as described in claim 6 or 11, wherein: The cloud platform is used to acquire the operating parameters of the battery or cell in real time, and input the operating parameters into the electrolyte remaining amount measurement model to estimate the electrolyte remaining amount of the battery or cell output by the electrolyte remaining amount measurement model.

14. A battery management system, characterized in that, The battery management system is electrically connected to the battery or cell, and a trained electrolyte remaining quantity measurement model as described in claim 5 or 9 is deployed on the battery management system, wherein: The battery management system is used to acquire the operating parameters of the battery or cell in real time, and input the operating parameters into the electrolyte remaining amount measurement model to estimate the electrolyte remaining amount of the battery or cell output by the electrolyte remaining amount measurement model.

15. A device for measuring the remaining amount of electrolyte, characterized in that, include: The acquisition module is used to acquire the mass of the extruded electrolyte of the battery cell under test, and the mass of the reference electrolyte which is of the same origin as the electrolyte in the battery cell under test; The processing module is used to perform the same weight loss treatment operation on the reference electrolyte and the cell under test after squeezing, and to determine the mass of the reference electrolyte and the cell under test after undergoing the weight loss treatment operation respectively; The measurement module is used to determine the mass of electrolyte attached to the battery cell under test based on the mass change ratio of the reference electrolyte before and after the weight loss treatment operation, and the mass change of the battery cell under test before and after the weight loss treatment operation. The calculation module is used to determine the remaining amount of electrolyte in the battery cell under test based on the mass of the extruded electrolyte and the mass of electrolyte adhering to the battery cell under test.

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