Battery cell negative pressure formation detection method and device, storage medium and electronic equipment

Abstract

The invention discloses a battery cell negative pressure formation detection method and device, a storage medium and electronic equipment. The method comprises the following steps: acquiring the current liquid level height of a buffer cup in formation equipment in the process of performing negative pressure formation on a target battery cell by the formation equipment; determining the cell type of the target cell; determining a current liquid level early warning range corresponding to the target battery cell from a plurality of liquid level early warning ranges based on the battery cell type; and determining an abnormal detection result of the negative pressure formation process based on whether the current liquid level height is within the current liquid level early warning range or not. Whether the liquid level is in a safe and effective early warning range or not is determined by monitoring the liquid level height of the buffer cup in the formation equipment and combining the type of the battery cell. According to the invention, the technical problem that the battery cell negative pressure formation detection method in the prior art cannot accurately distinguish the abnormity in the battery cell negative pressure formation process is solved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a method, device, storage medium and electronic equipment for detecting negative pressure formation of a battery cell. Background Art

[0002] Lithium battery is a secondary battery with lithium ions as active ions. It has the advantages of high energy density and high operating voltage. As environmental protection is increasingly valued, the demand for lithium batteries in new energy vehicles and energy storage projects is exploding. Lithium battery formation is an important process for activating batteries, which has an important impact on maintaining the cycle performance and service life of batteries. During formation, a solid electrolyte interface film will be formed on the surface of the negative electrode, accompanied by the decomposition of the electrolyte and gas production. The generated gas needs to be discharged from the battery in time, otherwise it will cause adverse consequences to the battery (such as black spots on the interface, lithium precipitation or battery bulging). Therefore, formation usually needs to be carried out under negative pressure conditions.

[0003] In actual production, for the negative pressure formation process involving battery cells of different shapes, sizes, or different main materials and components, the negative pressure pressure, the length of negative pressure time, and the amount of electrolyte extracted by negative pressure are all complicated and tedious process parameters. Moreover, as the production equipment is used for a long time, the equipment is worn and aged, and the electrolyte crystallization and blockage in the buffer cup or connecting hose are prone to occur. How to determine whether the existing equipment matches the corresponding process, whether the equipment tooling needs to be replaced, and what should determine the frequency of replacement are all relatively difficult processes. However, the battery cell negative pressure formation detection method in the related art cannot timely and accurately identify the above abnormal problems existing in the battery cell negative pressure formation process, which leads to problems such as low battery production efficiency and poor quality.

[0004] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0005] The embodiments of the present invention provide a battery cell negative pressure formation detection method, device, storage medium and electronic device to at least solve the technical problem that the battery cell negative pressure formation detection method in the related art cannot accurately identify the abnormalities existing in the battery cell negative pressure formation process.

[0006] According to one aspect of an embodiment of the present invention, a method for detecting negative pressure formation of a battery cell is provided, comprising: obtaining the current liquid level height of a buffer cup in a formation device during the process of negative pressure formation of a target battery cell by the formation device, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; determining the battery cell type of the target battery cell; based on the battery cell type, determining the current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges, wherein the multiple liquid level warning ranges correspond one to one to multiple battery cell types; determining the abnormal detection result of the negative pressure formation process based on whether the current liquid level height is within the current liquid level warning range. By monitoring the liquid level height of the buffer cup in the formation device, combined with the battery cell type, it is determined whether the liquid level is within a safe and effective warning range. This helps to detect abnormalities in a timely manner during the negative pressure formation process and avoid battery cell performance degradation or equipment failure due to improper electrolyte management.

[0007] Optionally, before determining the current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges based on the battery cell type, the method also includes: obtaining any liquid level warning range among the multiple liquid level warning ranges by: in a process of negative pressure formation of any type of battery cell among multiple battery cell types using formation equipment, obtaining operating parameters corresponding to any type of battery cell when the cache cup is in multiple page height ranges, and obtaining battery cell operating parameters corresponding to multiple liquid level height ranges; determining the liquid level warning range of any type of battery cell based on the battery cell operating parameters corresponding to the multiple liquid level height ranges; and obtaining multiple liquid level warning ranges by using the method of obtaining the liquid level warning range of any type of battery cell.

[0008] The above method describes in detail how to establish a liquid level warning range database, and through negative pressure formation experiments on different battery cell types, collect the operating parameters of the buffer cup at different liquid level heights, and analyze and obtain the liquid level warning range of each battery cell type. This ensures that the setting of the liquid level warning range is targeted and can adapt to the formation requirements of different battery cell types.

[0009] Optionally, the operating parameters include at least: battery cell capacity, the number of black spots on the battery cell interface, and formation fluid loss; wherein the battery cell capacity is used to indicate the ability of the battery to store and release electrical energy, and the formation fluid loss is used to indicate the degree of electrolyte loss in the battery cell.

[0010] The above methods clarify the specific content and significance of the operating parameters. The cell capacity, the number of black spots on the cell interface and the amount of liquid loss during formation reflect the cell's energy storage capacity, interface quality and electrolyte stability, respectively. These parameters directly affect the performance and life of the cell. By monitoring these parameters, the quality of the formation process can be comprehensively evaluated and potential problems in the formation process can be discovered in a timely manner.

[0011] Optionally, the liquid level warning range of any type of battery cell is determined based on the operating parameters corresponding to any type of battery cell in multiple liquid level height ranges, including: determining score values ​​corresponding to the multiple liquid level height ranges based on the battery cell capacity, the number of black spots on the battery cell interface and the amount of liquid loss caused by formation that correspond to the multiple liquid level height ranges; and determining the liquid level warning range of any type of battery cell from the multiple liquid level height ranges based on the score values ​​corresponding to the multiple liquid level height ranges.

[0012] The above method illustrates the specific calculation method of the scoring value. By quantitatively scoring the battery cell capacity, the number of black spots on the battery cell interface and the amount of liquid loss during formation, the comprehensive score of each liquid level height range can be accurately determined, and then the most suitable liquid level warning range can be found to ensure the stability and efficiency of the formation process.

[0013] Optionally, based on the cell capacity, the number of black spots on the cell interface and the amount of fluid loss caused by formation corresponding to any type of cell in multiple liquid level height ranges, score values ​​corresponding to the multiple liquid level height ranges are determined, including: obtaining the score value corresponding to any liquid level height range in the multiple liquid level height ranges by: determining a first weight value corresponding to the cell capacity, a second weight value corresponding to the number of black spots on the cell interface and a third weight value corresponding to the amount of fluid loss caused by formation; performing weighted calculation based on the cell capacity, the number of black spots on the cell interface and the amount of fluid loss caused by formation corresponding to any type of cell in any liquid level height range, as well as the first weight value, the second weight value and the third weight value to obtain the score value corresponding to any liquid level height range; obtaining the score values ​​corresponding to the multiple liquid level height ranges by adopting the method of obtaining the score value corresponding to any liquid level height range.

[0014] The above method details the specific steps of calculating the score value, including determining the weight value of each operating parameter and performing weighted calculation based on these parameters and weights. The setting of the weight value takes into account the importance of different parameters on the performance of the battery cell. The score value after weighted calculation can more accurately reflect the impact of different liquid level heights on the formation process.

[0015] Optionally, in the case where the negative pressure forming process includes: a pre-forming process and a formal forming process, obtaining the current liquid level height of the cache cup in the forming equipment during the negative pressure forming process of the forming equipment on the target battery cell includes: obtaining the current liquid level height of the cache cup during the formal forming process of the forming equipment on the target battery cell, wherein the current used in the formal forming process is greater than the current used in the pre-forming process.

[0016] The above method distinguishes the pre-forming and formal forming stages in the negative pressure forming process, and points out the importance of monitoring the liquid level height in the formal forming stage. Because the current intensity in the formal forming stage is higher and the impact on the electrolyte is more significant, monitoring its liquid level changes helps to more accurately judge the normality of the forming process.

[0017] Optionally, based on whether the current liquid level height is within the current liquid level warning range, the abnormal detection result of the negative pressure formation process is determined, including: when the current liquid level height exceeds the current liquid level warning range, the abnormal detection result is determined to be: there is an abnormality in the negative pressure formation process; when the current liquid level height is within the current liquid level warning range, the abnormal detection result is determined to be: the negative pressure formation process is normal.

[0018] The above method clarifies the logic of determining whether the formation process is abnormal based on the liquid level warning range. This instant feedback mechanism can quickly respond to abnormal conditions in the formation process, avoiding equipment failures and production delays caused by improper electrolyte management. It is particularly suitable for battery production lines with a high degree of automation, improving battery production efficiency and battery quality.

[0019] According to another aspect of an embodiment of the present invention, a battery cell negative pressure formation detection device is also provided, including: a liquid level height acquisition module, used to obtain the current liquid level height of a buffer cup in a formation device during a process in which the formation device performs negative pressure formation on a target battery cell, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; a battery cell type determination module, used to determine the battery cell type of the target battery cell; a warning range determination module, used to determine a current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges based on the battery cell type, wherein the multiple liquid level warning ranges correspond one-to-one to multiple battery cell types; and a result determination module, used to determine the abnormal detection result of the negative pressure formation process based on whether the current liquid level height is within the current liquid level warning range.

[0020] According to another aspect of an embodiment of the present invention, a non-volatile storage medium is provided, wherein the non-volatile storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing any one of the battery cell negative pressure formation detection methods.

[0021] According to another aspect of an embodiment of the present invention, there is also provided an electronic device, comprising one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement any one of the battery cell negative pressure formation detection methods.

[0022] In an embodiment of the present invention, the current liquid level height of the buffer cup in the formation equipment is obtained during the process of negative pressure formation of the target battery cell by the formation equipment, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; the battery cell type of the target battery cell is determined; based on the battery cell type, the current liquid level warning range corresponding to the target battery cell is determined from multiple liquid level warning ranges, wherein the multiple liquid level warning ranges correspond one to one to multiple battery cell types; based on whether the current liquid level height is within the current liquid level warning range, the abnormal detection result of the negative pressure formation process is determined. By monitoring the liquid level height of the buffer cup in the formation equipment, combined with the battery cell type, it is determined whether the liquid level is within a safe and effective warning range. This helps to promptly detect abnormalities during the negative pressure formation process and avoid degradation of battery cell performance or equipment failure due to improper electrolyte management. It achieves the purpose of monitoring the liquid level height of the buffer cup in the formation equipment and determining whether the liquid level is within a safe and effective warning range in combination with the battery cell type, thereby achieving the technical effect of promptly detecting abnormalities during the negative pressure formation process and avoiding degradation of battery cell performance or equipment failure due to improper electrolyte management, thereby solving the technical problem that the battery cell negative pressure formation detection method in the related art cannot accurately identify abnormalities existing in the battery cell negative pressure formation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0024] Figure 1 is a flow chart of a negative pressure formation detection method for a battery cell according to an embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of capacity distribution corresponding to different liquid level heights according to an optional embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of the number of black spots on the cell interface corresponding to different liquid level heights according to an embodiment of the present invention;

[0027] Figure 4 is a schematic diagram of formation loss amounts corresponding to different liquid level heights according to an optional embodiment of the present invention;

[0028] Figure 5 is a schematic diagram of a battery cell negative pressure formation detection device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0031] According to an embodiment of the present invention, a method embodiment of negative pressure formation detection of a battery cell is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0032] Figure 1 is a flow chart of a method for detecting negative pressure formation of a battery cell according to an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0033] Step S102, obtaining the current liquid level height of a buffer cup in the formation equipment during the process of negative pressure formation of the target battery cell by the formation equipment, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process;

[0034] Optionally, negative pressure formation of the battery cell means that during the battery manufacturing process, negative pressure is applied to the battery cell in a sealed environment to promote the penetration and distribution of the electrolyte between the positive and negative electrodes, thereby improving the performance and stability of the battery cell. Negative pressure formation can help the electrolyte penetrate more evenly between the positive and negative electrodes of the battery cell, reduce gas generation and internal impedance, and thus improve the performance and cycle life of the battery. This treatment method can effectively improve the charge and discharge performance of the battery cell, and increase the energy density and cycle stability of the battery. Negative pressure formation is an important process in battery production that can improve the quality and performance of the battery.

[0035] Optionally, during the negative pressure formation process, the buffer cup is used to temporarily store the electrolyte extracted from the target battery cell housing. Monitoring the current liquid level of the buffer cup can help control the amount and change of electrolyte, so as to detect any abnormal situation in time and ensure normal operation.

[0036] Optionally, the target battery cell can be a battery cell that has not been formed after one injection (i.e., electrolyte injection) and high-temperature immersion during the battery generation process, and the target battery cell can be a lithium battery cell. The formation equipment may include a battery cell, a probe, a connecting hose, a buffer cup, a bus bar, a negative pressure source, a liquid level detection device, a liquid level alarm device, etc. When the battery cell is formed, a part of the electrolyte in the shell will be drawn to the buffer cup under the continuous action of the negative pressure external force. At the end, after the vacuum is broken, the electrolyte in the buffer cup will flow back to the battery cell, thereby achieving the effect of negative pressure formation.

[0037] Step S104, determining the cell type of the target cell;

[0038] Optionally, the cell type can be determined based on different shapes, or based on the size of the cell, different main materials, components, etc. The cell type is determined in order to set corresponding operating parameters and warning ranges according to different cell types. Different types of cells may require different processing methods and abnormal characteristics. For example, for different types of cells, there are differences in the size of the corresponding negative pressure, the length of the negative pressure time, and the amount of electrolyte extracted by the negative pressure. As the production equipment accumulates in use, the corresponding equipment wears and ages, and the crystallization blockage of the electrolyte in the buffer cup or the connecting hose is prone to occur. Therefore, by determining the cell type, the negative pressure formation process can be better controlled and monitored.

[0039] Step S106, based on the cell type, determining a current liquid level warning range corresponding to the target cell from a plurality of liquid level warning ranges, wherein the plurality of liquid level warning ranges correspond one-to-one to a plurality of cell types;

[0040] Optionally, the corresponding liquid level warning range is determined according to the type of the target battery cell. Different types of battery cells may require different liquid level control ranges. By setting a suitable warning range, the liquid level change can be effectively monitored to avoid damage to the battery cell caused by excessively high or low liquid levels.

[0041] Step S108, determining the abnormality detection result of the negative pressure forming process based on whether the current liquid level height is within the current liquid level warning range.

[0042] Optionally, in combination with whether the current liquid level is within the current liquid level warning range, it can be determined whether there are abnormal conditions in the negative pressure formation process. If the current liquid level exceeds the warning range, it may mean improper electrolyte management, problems with the battery cell, or equipment abnormalities. Timely detection and handling of abnormal conditions can avoid degradation of battery cell performance or equipment failure. In the above method, the current liquid level of the buffer cup can be used to preliminarily determine whether the battery cell formation and capacity separation interface are good. Without disassembling a large number of batteries, it is possible to quickly and easily determine whether the existing process is reasonable or whether the current equipment needs maintenance.

[0043] Through the above steps S102 to S108, the purpose of monitoring the liquid level height of the buffer cup in the formation equipment and determining whether the liquid level is within a safe and effective warning range in combination with the battery cell type can be achieved, thereby achieving the technical effect of timely discovering abnormalities during the negative pressure formation process and avoiding battery cell performance degradation or equipment failure due to improper electrolyte management, thereby solving the technical problem that the battery cell negative pressure formation detection method in the related art cannot accurately identify abnormalities existing in the battery cell negative pressure formation process.

[0044] In an optional embodiment, before determining the current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges based on the battery cell type, the method further includes: obtaining any liquid level warning range among the multiple liquid level warning ranges by: in a process of negative pressure formation of any type of battery cell among multiple battery cell types using formation equipment, obtaining operating parameters corresponding to any type of battery cell when the cache cup is in multiple page height ranges, and obtaining battery cell operating parameters corresponding to multiple liquid level height ranges; determining the liquid level warning range of any type of battery cell based on the battery cell operating parameters corresponding to the multiple liquid level height ranges; and obtaining multiple liquid level warning ranges by using the method of obtaining the liquid level warning range of any type of battery cell.

[0045] Optionally, negative pressure formation is performed separately for each type of battery cell, and during the negative pressure formation process, the operating parameters of the battery cell when the cache cup is in multiple page height ranges are obtained. The battery cell operating parameters can reflect the operating status and operating characteristics of the battery cell. Therefore, based on the battery cell operating parameters, a liquid level warning range suitable for the operating characteristics of each type of battery cell can be obtained in a targeted manner.

[0046] The above method describes in detail how to establish a liquid level warning range database, and through negative pressure formation experiments on different battery cell types, collect the operating parameters of the buffer cup at different liquid level heights, and analyze and obtain the liquid level warning range of each battery cell type. This ensures that the setting of the liquid level warning range is targeted and can adapt to the formation requirements of different battery cell types.

[0047] In an optional embodiment, the operating parameters include at least: battery cell capacity, the number of black spots on the battery cell interface, and formation loss; wherein the battery cell capacity is used to indicate the ability of the battery to store and release electrical energy, and the formation loss is used to indicate the degree of electrolyte loss in the battery cell.

[0048] Optionally, the cell capacity refers to the ability of the battery to store and release electrical energy, expressed in ampere-hours (Ah). The size of the cell capacity directly affects the battery's service life and output power, and is an important indicator for evaluating battery performance. During the cell formation process, under normal circumstances, there should be no black spots on the cell surface. The appearance of black spots may indicate problems inside the cell, such as electrolyte leakage, uneven electrode reaction, etc. Therefore, recording the number of black spots on the cell interface can help evaluate the quality and formation effect of the cell. During the battery formation process, electrolyte loss may occur due to different reasons, that is, the formation fluid loss. The size of the formation fluid loss can reflect the stability and sealing of the electrolyte in the battery. Excessive fluid loss may cause battery performance degradation or safety problems. Therefore, monitoring the formation fluid loss can help evaluate the quality and formation effect of the battery.

[0049] The above methods clarify the specific content and significance of the operating parameters. The cell capacity, the number of black spots on the cell interface and the amount of liquid loss during formation reflect the cell's energy storage capacity, interface quality and electrolyte stability, respectively. These parameters directly affect the performance and life of the cell. By monitoring these parameters, the pros and cons of the formation process can be comprehensively evaluated, and potential problems in the formation process can be discovered in a timely manner, such as the degradation of cell performance that may result from improper electrolyte management, the unsuitability of formation equipment, etc.

[0050] In an optional embodiment, the liquid level warning range of any type of battery cell is determined based on the operating parameters corresponding to any type of battery cell in multiple liquid level height ranges, including: determining the score values ​​corresponding to the multiple liquid level height ranges based on the battery cell capacity, the number of black spots on the battery cell interface and the amount of liquid loss caused by formation corresponding to the multiple liquid level height ranges; and determining the liquid level warning range of any type of battery cell from the multiple liquid level height ranges based on the score values ​​corresponding to the multiple liquid level height ranges.

[0051] The above method explains the specific calculation method of the scoring value. By quantitatively scoring the cell capacity, the number of black spots on the cell interface, and the amount of liquid loss during formation, the comprehensive score of each liquid level height range can be accurately determined, and then the most suitable liquid level warning range can be found to ensure the stability and efficiency of the formation process. In addition, this scoring mechanism can quantify the impact of different liquid level heights on cell performance, providing strong data support for quality control in the battery production process, helping to achieve refined management in a large-scale production environment, reduce battery defective rates, and improve production efficiency.

[0052] In an optional embodiment, based on the cell capacity, the number of black spots on the cell interface and the amount of liquid loss respectively corresponding to any type of cell in multiple liquid level height ranges, score values ​​respectively corresponding to the multiple liquid level height ranges are determined, including: obtaining the score value corresponding to any liquid level height range in the multiple liquid level height ranges by: determining a first weight value corresponding to the cell capacity, a second weight value corresponding to the number of black spots on the cell interface and a third weight value corresponding to the amount of liquid loss; performing weighted calculation based on the cell capacity, the number of black spots on the cell interface and the amount of liquid loss respectively corresponding to any type of cell in any liquid level height range, as well as the first weight value, the second weight value and the third weight value to obtain the score value corresponding to any liquid level height range; obtaining the score values ​​respectively corresponding to the multiple liquid level height ranges by adopting the method of obtaining the score value corresponding to any liquid level height range.

[0053] The above method refines the specific steps of calculating the score value, including determining the weight value of each operating parameter and performing weighted calculation based on these parameters and weights. The setting of the weight value takes into account the importance of different parameters on the performance of the battery cell. By setting corresponding weight values ​​for the battery cell capacity, the number of black spots on the battery cell interface, and the amount of liquid loss during formation, and performing weighted calculation based on the weight value, the score value obtained can more accurately reflect the impact of different liquid level heights on the formation process.

[0054] Optionally, the weight values ​​set for the battery cell capacity, the number of black spots on the battery cell interface, and the amount of liquid loss due to formation (i.e., the first weight value, the second weight value, and the third weight value) can be the same or different. They can be set according to actual scenario requirements, battery cell characteristics, etc., and are not specifically limited here.

[0055] In an optional embodiment, when the negative pressure forming process includes: a pre-forming process and a formal forming process, obtaining the current liquid level height of a cache cup in the forming equipment during the negative pressure forming process of the forming equipment on the target battery cell includes: obtaining the current liquid level height of the cache cup during the formal forming process of the forming equipment on the target battery cell, wherein the current used in the formal forming process is greater than the current used in the pre-forming process.

[0056] The above method distinguishes the pre-forming stage and the formal forming stage in the negative pressure forming process, and points out the importance of monitoring the liquid level height in the formal forming stage, because the current intensity in the formal forming stage is higher and the impact on the electrolyte is more significant. Monitoring its liquid level change helps to more accurately judge the normality of the forming process. For example, before forming, a small current of 0.001-0.002 coulomb (C) is used for pre-forming for 30-60 minutes (min) to increase the further infiltration of the electrolyte. After 30 minutes, the formal forming begins. The forming current can be controlled at 0.05C-0.2C for about 30-60 minutes, and the liquid level height in the formal forming stage is recorded; the battery cell is always formed under a vacuum degree of negative pressure of -90 to -30 kilopascals (kpa). The phased monitoring strategy and targeted current setting can more accurately capture the key changes in the formation process. Especially in the formal formation stage, the dynamic changes of the electrolyte have a more significant impact on the performance of the battery cell. It is suitable for quality control in the battery manufacturing process to ensure that the formation effect of each link is optimal.

[0057] In an optional embodiment, based on whether the current liquid level height is within the current liquid level warning range, the abnormal detection result of the negative pressure formation process is determined, including: when the current liquid level height exceeds the current liquid level warning range, the abnormal detection result is determined to be: there is an abnormality in the negative pressure formation process; when the current liquid level height is within the current liquid level warning range, the abnormal detection result is determined to be: the negative pressure formation process is normal.

[0058] The above method clarifies the logic of determining whether the formation process is abnormal based on the liquid level warning range. If the current monitored liquid level exceeds the preset liquid level warning range, it will trigger an abnormal detection result, indicating that there may be problems in the formation process and that process parameters need to be adjusted or equipment maintenance needs to be performed in a timely manner; otherwise, it indicates that the formation process is normal and can continue. This instant feedback mechanism can quickly respond to abnormal conditions in the formation process, avoiding production delays caused by improper electrolyte management, inappropriate configuration of formation equipment and its related parameters, and equipment aging. It is particularly suitable for battery production lines with a high degree of automation to improve battery production efficiency and battery quality.

[0059] Based on the above embodiments and optional embodiments, the present invention proposes an optional implementation method of a negative pressure formation detection method for a battery cell, the method comprising: taking a battery cell that has not been formed after a liquid injection (i.e., an electrolyte is injected) and high-temperature immersion as an experimental sample (taking a nominal capacity of 202 ampere-hours (Ah) as an example), and before the experiment, the page height of the buffer cup needs to be marked accordingly, and the formation equipment can monitor the height of the liquid level of the buffer cup, specifically:

[0060] S1, before formation, pre-form the battery cell with a small current of 0.001-0.002C for 30-60 minutes to increase the further infiltration of the electrolyte. After 30 minutes, formal formation begins. The formation current can be controlled at 0.05C-0.2C for about 30-60 minutes, and the liquid level at this stage is recorded;

[0061] S2, the battery cell is always formed under a vacuum of negative pressure (-90 to -30) kPa;

[0062] S3, collects data such as the liquid level height at different rates and negative pressures in the buffer cup, the cell capacity, the number of black spots on the cell interface, and the amount of liquid loss during formation, for analysis.

[0063] The experimental results are as follows Figure 2 , Figure 3 , Figure 4 As shown, Figure 2 is a schematic diagram of capacity distribution corresponding to different liquid level heights according to an optional embodiment of the present invention. Figure 3 is a schematic diagram of the number of black spots on the cell interface corresponding to different liquid level heights according to an embodiment of the present invention. Figure 4 It is a schematic diagram of the amount of formation loss corresponding to different liquid level heights according to an optional embodiment of the present invention. From a comprehensive analysis, the liquid level needs to be maintained at 6-9mL to meet the needs of the 202Ah battery cell in this experiment. On the basis of fixing the battery cell system, battery cell process parameters, and the formation equipment used, the liquid level critical point corresponding to the formation equipment of 6 to 9mL can be solidified as the liquid level warning range of the battery cell. By generating personnel, inspection quality, on-site processes, and equipment, it can be set to add a liquid level alarm device on the formation equipment. In this way, it is possible to quickly track which existing equipment needs maintenance and replacement. For example, when a large number of critical points of solidification of the formation liquid surface appear, it is necessary to consider whether the current process and equipment are not compatible with the current battery cell materials, so that the internal electrochemical reaction of the formation becomes a visualized process.

[0064] In the process of using formation equipment to perform negative pressure formation on various types of battery cells, data such as the liquid level height at different rates and negative pressures in the buffer cup of the formation equipment, the battery cell capacity, the number of black spots on the battery cell interface, and the amount of liquid loss during formation are collected and analyzed to determine the liquid level warning ranges corresponding to the various types of battery cells.

[0065] When the mass production process is fixed, the method provided in the embodiment can accurately indicate which points need maintenance through intuitive changes in the liquid level, thereby reducing maintenance costs and time. When developing new materials and different systems, this embodiment can quickly formulate corresponding design processes and corresponding parameters based on the liquid level and interface of the buffer cup, thereby reducing process verification time.

[0066] In this embodiment, a battery cell negative pressure formation detection device is also provided, which is used to implement the above-mentioned embodiments and preferred embodiments, and will not be repeated here. As used below, the terms "module" and "device" can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0067] According to an embodiment of the present invention, there is also provided an embodiment of a device for implementing the above-mentioned negative pressure formation detection method for a battery cell. Figure 5 is a structural schematic diagram of a negative pressure formation detection device for a battery cell according to an embodiment of the present invention. Figure 5 As shown, the above-mentioned battery cell negative pressure formation detection device includes: a liquid level height acquisition module 500, a battery cell type determination module 502, a warning range determination module 504, and a result determination module 506, wherein:

[0068] The liquid level acquisition module 500 is used to acquire the current liquid level of the buffer cup in the formation equipment during the process of the formation equipment performing negative pressure formation on the target battery cell, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process;

[0069] A cell type determination module 502, connected to the liquid level acquisition module 500, for determining the cell type of the target cell;

[0070] The warning range determination module 504 is connected to the battery cell type determination module 502, and is used to determine the current liquid level warning range corresponding to the target battery cell from the multiple liquid level warning ranges based on the battery cell type, wherein the multiple liquid level warning ranges correspond to the multiple battery cell types one by one;

[0071] The result determination module 506 is connected to the warning range determination module 504 and is used to determine the abnormality detection result of the negative pressure forming process based on whether the current liquid level height is within the current liquid level warning range.

[0072] In an embodiment of the present invention, a liquid level height acquisition module 500 is provided to acquire the current liquid level height of a buffer cup in a formation device during a process in which the formation device performs negative pressure formation on a target battery cell, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; a battery cell type determination module 502 is connected to the liquid level height acquisition module 500 and is used to determine the battery cell type of the target battery cell; an early warning range determination module 504 is connected to the battery cell type determination module 502 and is used to determine the current liquid level early warning range corresponding to the target battery cell from a plurality of liquid level early warning ranges based on the battery cell type, wherein the plurality of liquid level early warning ranges are associated with the plurality of liquid level early warning ranges. The result determination module 506 is connected to the warning range determination module 504, and is used to determine the abnormal detection result of the negative pressure formation process based on whether the current liquid level height is within the current liquid level warning range, thereby achieving the purpose of monitoring the liquid level height of the buffer cup in the formation equipment and determining whether the liquid level is within a safe and effective warning range in combination with the battery cell type, thereby achieving the technical effect of timely discovering abnormalities in the negative pressure formation process and avoiding battery cell performance degradation or equipment failure caused by improper electrolyte management, thereby solving the technical problem that the battery cell negative pressure formation detection method in the related art cannot accurately identify the abnormalities in the battery cell negative pressure formation process.

[0073] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0074] It should be noted that the above-mentioned liquid level acquisition module 500, battery cell type determination module 502, warning range determination module 504, and result determination module 506 correspond to steps S102 to S108 in the embodiment, and the examples and application scenarios implemented by the above-mentioned modules and corresponding steps are the same, but are not limited to the contents disclosed in the above-mentioned embodiment. It should be noted that the above-mentioned modules can be run in a computer terminal as part of the device.

[0075] It should be noted that the optional or preferred implementation of this embodiment can refer to the relevant description in the embodiment, which will not be repeated here.

[0076] The above-mentioned battery cell negative pressure formation detection device may also include a processor and a memory. The above-mentioned liquid level height acquisition module 500, battery cell type determination module 502, warning range determination module 504, result determination module 506, etc. are all stored in the memory as program modules, and the processor executes the above-mentioned program modules stored in the memory to realize the corresponding functions.

[0077] The processor includes a kernel, which retrieves the corresponding program module from the memory. The kernel may be one or more. The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. The memory includes at least one memory chip.

[0078] According to an embodiment of the present application, an embodiment of a non-volatile storage medium is also provided. Optionally, in this embodiment, the non-volatile storage medium includes a stored program, wherein when the program is executed, the device where the non-volatile storage medium is located is controlled to execute any of the above-mentioned negative pressure formation detection methods for battery cells.

[0079] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a computer terminal group in a computer network, or in any mobile terminal in a mobile terminal group, and the non-volatile storage medium includes a stored program.

[0080] Optionally, when the program is running, the device where the non-volatile storage medium is located is controlled to perform the following functions: obtaining the current liquid level height of the buffer cup in the formation device during the process of negative pressure formation of the target battery cell by the formation device, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; determining the battery cell type of the target battery cell; based on the battery cell type, determining the current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges, wherein multiple liquid level warning ranges correspond one to one to multiple battery cell types; determining the abnormal detection result of the negative pressure formation process based on whether the current liquid level height is within the current liquid level warning range. By monitoring the liquid level height of the buffer cup in the formation device and combining the battery cell type, it is determined whether the liquid level is within a safe and effective warning range. This helps to detect abnormalities in a timely manner during the negative pressure formation process and avoid battery cell performance degradation or equipment failure due to improper electrolyte management.

[0081] According to an embodiment of the present application, an embodiment of a processor is also provided. Optionally, in this embodiment, the processor is used to run a program, wherein when the program is run, any of the above-mentioned battery cell negative pressure formation detection methods is executed.

[0082] According to an embodiment of the present application, an embodiment of a computer program product is also provided. When executed on a data processing device, it is suitable for executing a program that initializes any one of the steps of the above-mentioned battery cell negative pressure formation detection method.

[0083] Optionally, the above-mentioned computer program product, when executed on a data processing device, is suitable for executing a program that is initialized with the following method steps: obtaining the current liquid level height of the buffer cup in the formation device during the process of negative pressure formation of the target battery cell by the formation device, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; determining the battery cell type of the target battery cell; based on the battery cell type, determining the current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges, wherein multiple liquid level warning ranges correspond one to one to multiple battery cell types; determining the abnormal detection result of the negative pressure formation process based on whether the current liquid level height is within the current liquid level warning range. By monitoring the liquid level height of the buffer cup in the formation device, combined with the battery cell type, it is determined whether the liquid level is within a safe and effective warning range. This helps to detect abnormalities in a timely manner during the negative pressure formation process and avoid battery cell performance degradation or equipment failure caused by improper electrolyte management.

[0084] The embodiment of the present invention provides an electronic device, which includes a processor, a memory, and a program stored in the memory and can be run on the processor. When the processor executes the program, the following steps are implemented: obtaining the current liquid level height of the buffer cup in the formation device during the process of the formation device performing negative pressure formation on the target battery cell, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; determining the battery cell type of the target battery cell; based on the battery cell type, determining the current liquid level warning range corresponding to the target battery cell from multiple liquid level warning ranges, wherein the multiple liquid level warning ranges correspond to multiple battery cell types one by one; based on whether the current liquid level height is within the current liquid level warning range, determining the abnormal detection result of the negative pressure formation process. By monitoring the liquid level height of the buffer cup in the formation device, combined with the battery cell type, it is determined whether the liquid level is within a safe and effective warning range. This helps to timely discover abnormalities during the negative pressure formation process and avoid battery cell performance degradation or equipment failure caused by improper electrolyte management.

[0085] The above sequence of the embodiments of the present invention is for description only and does not represent the superiority or inferiority of the embodiments.

[0086] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0087] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the above modules can be a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, modules or indirect coupling or communication connection of modules, which can be electrical or other forms.

[0088] The modules described above as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0089] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of software functional modules.

[0090] If the above-mentioned integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable non-volatile storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a non-volatile storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the various embodiments of the present invention. The aforementioned non-volatile storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0091] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for detecting negative pressure formation of a battery cell, characterized in that: include: Acquiring the current liquid level height of a buffer cup in the formation equipment during the process of negative pressure formation of the target battery cell by the formation equipment, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; Determining the cell type of the target cell; Based on the battery cell type, determining a current liquid level warning range corresponding to the target battery cell from a plurality of liquid level warning ranges, wherein the plurality of liquid level warning ranges correspond one-to-one to a plurality of battery cell types; Based on whether the current liquid level height is within the current liquid level warning range, an abnormality detection result of the negative pressure forming process is determined.

2. The method according to claim 1, characterized in that Before determining the current liquid level warning range corresponding to the target battery cell from a plurality of liquid level warning ranges based on the battery cell type, the method further includes: Any one of the multiple liquid level warning ranges is obtained by: In the process of negative pressure forming of any type of battery cell among the multiple types of battery cells by using the forming equipment, the operating parameters corresponding to the battery cell of any type when the buffer cup is in multiple page height ranges are obtained, and the battery cell operating parameters corresponding to the multiple liquid level height ranges are obtained; Determining a liquid level warning range of any type of battery cell based on battery cell operating parameters corresponding to the multiple liquid level height ranges; The multiple liquid level warning ranges are obtained by adopting a method of obtaining the liquid level warning range of any type of battery cell.

3. The method according to claim 2, characterized in that The operating parameters include at least: battery cell capacity, number of black spots on the battery cell interface, and liquid loss due to formation; The cell capacity is used to indicate the ability of the battery to store and release electrical energy, and the formation fluid loss is used to indicate the degree of electrolyte loss in the cell.

4. The method according to claim 3, characterized in that: The determining the liquid level warning range of any type of battery cell based on the operating parameters respectively corresponding to the battery cells of any type when the multiple liquid level height ranges are present includes: Determine the score values ​​corresponding to the multiple liquid level height ranges respectively based on the battery cell capacity, the number of black spots on the battery cell interface and the amount of liquid loss caused by formation corresponding to the multiple liquid level height ranges respectively; Based on the score values ​​respectively corresponding to the multiple liquid level height ranges, the liquid level warning range of the battery cell of any type is determined from the multiple liquid level height ranges.

5. The method according to claim 4, characterized in that The determining of the score values ​​corresponding to the multiple liquid level ranges based on the battery cell capacity, the number of black spots on the battery cell interface and the amount of liquid loss respectively corresponding to any type of battery cell when the multiple liquid level ranges are present includes: The score value corresponding to any liquid level height range in the multiple liquid level height ranges is obtained by: Determine a first weight value corresponding to the battery cell capacity, a second weight value corresponding to the number of black spots on the battery cell interface, and a third weight value corresponding to the formation fluid loss; Based on the cell capacity, the number of black spots on the cell interface and the amount of liquid loss corresponding to each type of cell in the range of the liquid level, and the first weight value, the second weight value and the third weight value, a weighted calculation is performed to obtain a score value corresponding to the range of the liquid level; The scoring values ​​corresponding to the plurality of liquid level height ranges are obtained by obtaining the scoring value corresponding to any one of the liquid level height ranges.

6. The method according to claim 5, characterized in that In the case where the negative pressure forming process includes: a pre-forming process and a formal forming process, the acquisition of the current liquid level height of the buffer cup in the forming device during the negative pressure forming process of the target battery cell by the forming device includes: The current liquid level of the buffer cup is obtained during the formal formation process performed by the formation equipment on the target battery cell, wherein the current used in the formal formation process is greater than the current used in the pre-formation process.

7. The method according to any one of claims 1 to 6, characterized in that The determining of the abnormality detection result of the negative pressure forming process based on whether the current liquid level height is within the current liquid level warning range includes: In the case where the current liquid level height exceeds the current liquid level warning range, determining the abnormality detection result as: an abnormality exists in the negative pressure forming process; When the current liquid level height is within the current liquid level warning range, the abnormal detection result is determined as: the negative pressure forming process is normal.

8. A negative pressure formation detection device for a battery cell, characterized in that: include: A liquid level acquisition module, used to acquire the current liquid level of a buffer cup in the formation equipment during the process of negative pressure formation of the target battery cell by the formation equipment, wherein the buffer cup is used to temporarily store the electrolyte extracted from the shell of the target battery cell during the negative pressure formation process; A cell type determination module, used to determine the cell type of the target cell; an early warning range determination module, configured to determine, based on the battery cell type, a current liquid level early warning range corresponding to the target battery cell from a plurality of liquid level early warning ranges, wherein the plurality of liquid level early warning ranges correspond one-to-one to a plurality of battery cell types; The result determination module is used to determine the abnormality detection result of the negative pressure forming process based on whether the current liquid level height is within the current liquid level warning range.

9. A non-volatile storage medium, characterized in that: The non-volatile storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the battery cell negative pressure formation detection method according to any one of claims 1 to 7.

10. An electronic device, characterized in that: It includes one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the battery cell negative pressure formation detection method as described in any one of claims 1 to 7.

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