Method and system for injecting electrolyte into battery cell

Abstract

The application discloses a kind of battery injection method and system, the battery injection method includes: the deviation of the actual injection amount and reference injection amount of the injection battery group is obtained;In the case where deviation is not in injection amount qualified interval, based on deviation, determine a plurality of candidate injection adjustment amount;For each candidate injection adjustment amount, at least one injection amount evaluation index is respectively evaluated according to candidate injection adjustment amount, and the score corresponding to the candidate injection adjustment amount is obtained;Based on the target injection adjustment amount corresponding to the score that meets the preset condition in multiple scores, control injection equipment to injection battery to be injected is injected.The scheme provided by the application can improve the performance of battery.

Description

Technical Field

[0001] This application relates to the field of batteries, and in particular to a method and system for injecting electrolyte into battery cells. Background Technology

[0002] Electrolyte is a crucial component of battery cells, and the amount of electrolyte injected into a cell is a key control parameter in battery processing and production. Too much or too little electrolyte directly affects battery lifespan and safety performance. Therefore, how to control the amount of electrolyte injected into a cell to improve its performance is a problem that the industry urgently needs to solve. Summary of the Invention

[0003] In view of the above problems, this application provides a method and system for injecting electrolyte into battery cells to improve battery cell performance.

[0004] In a first aspect, this application provides a method for injecting electrolyte into battery cells. The method includes: obtaining the deviation between the actual injected volume of an already injected battery cell assembly and a reference injected volume; if the deviation is not within the acceptable range of injected volume, determining multiple candidate injected volume adjustment amounts based on the deviation; for each candidate injected volume adjustment amount, evaluating the candidate injected volume adjustment amount according to at least one injected volume evaluation index to obtain a score corresponding to the candidate injected volume adjustment amount; and controlling an injection device to inject electrolyte into the battery cell to be injected based on the target injected volume corresponding to the score that meets preset conditions among the multiple scores.

[0005] As described above, in this embodiment, when determining the target liquid injection adjustment amount for the battery cell to be injected, the deviation between the actual liquid injection amount and the reference liquid injection amount of the already injected battery cell group is first obtained. If the deviation is not within the acceptable liquid injection amount range (which can be the CP (Control Point) range), multiple candidate liquid injection adjustment amounts can be determined based on the deviation. Then, the candidate liquid injection adjustment amounts are evaluated using a liquid injection amount evaluation index to obtain a score corresponding to each candidate liquid injection adjustment amount. The candidate liquid injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment amount. Thus, in this embodiment, when the liquid injection amount deviation is not within the acceptable liquid injection amount range, the liquid injection adjustment amount is no longer determined solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment amounts are determined based on the deviation, and then scores for these multiple candidate liquid injection adjustment amounts are obtained based on the liquid injection amount evaluation index. From these, the candidate liquid injection adjustment amount whose score meets the preset conditions is selected as the target liquid injection adjustment amount. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection amount evaluation index is also referenced, thereby overcoming the limitation that the liquid injection amount is only adjusted when the deviation is within the CPP (CONTROL PROCESS POINT) range; and enabling the cell with better cell performance indicators to be obtained when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0006] In some embodiments, determining a plurality of candidate injection adjustment amounts based on the deviation includes: determining a deviation allowable range based on the deviation; and determining a plurality of candidate injection adjustment amounts within the deviation allowable range.

[0007] Determining multiple candidate liquid injection adjustment amounts within the allowable deviation range allows for setting reasonable boundary ranges for the liquid injection adjustment amounts, ensuring that all candidate adjustment amounts are within the safe liquid injection range for the battery cell, and minimizing the negative impact of all candidate adjustment amounts on the battery cell performance.

[0008] In some embodiments, determining multiple candidate injection adjustment amounts within the allowable deviation range includes: obtaining multiple deviation adjustment coefficients corresponding to the deviation; and adjusting the deviation based on the multiple deviation adjustment coefficients within the allowable deviation range to obtain multiple candidate injection adjustment amounts.

[0009] By setting a deviation coefficient within the allowable deviation range, a dual constraint condition of "range boundary + coefficient ratio" is formed. On the one hand, it can ensure that all candidate adjustment amounts are within the range of safe electrolyte injection for the battery cell. On the other hand, it can ensure that the multiple candidate electrolyte injection adjustment amounts are always quantified around the core of the deviation, avoiding deviations that may be caused by random values ​​within the range. Moreover, it can make the multiple candidate adjustment amounts as evenly distributed as possible within the allowable deviation range, which is more conducive to screening out the candidate electrolyte injection adjustment amounts that maximize the battery cell performance, thereby making the candidate electrolyte injection adjustment amounts accurately matched with the battery cell.

[0010] In some embodiments, the step of evaluating each candidate injection adjustment volume according to at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume includes: for each candidate injection adjustment volume, determining a candidate injection volume based on the candidate injection adjustment volume and a baseline injection volume; and evaluating the candidate injection volume according to at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume.

[0011] In this way, by determining the candidate injection volume based on the candidate injection adjustment volume and the benchmark injection volume, the adjustment volume can be converted into the actual injection volume. This allows the subsequent calculation of the score corresponding to the candidate injection adjustment volume using the injection volume evaluation index to be based directly on the actual injection volume of the battery cell, rather than the adjustment range. This makes it easier to control the injection equipment to inject liquid into the battery cell.

[0012] In some embodiments, there are multiple injection volume evaluation indicators. The step of evaluating the candidate injection volume according to at least one injection volume evaluation indicator to obtain a score corresponding to the candidate injection adjustment volume includes: for each candidate injection volume, evaluating the candidate injection volume according to each injection volume evaluation indicator to obtain a sub-score for each injection volume evaluation indicator; and summing the multiple sub-scores to obtain a score corresponding to the candidate injection adjustment volume.

[0013] By evaluating each candidate injection volume using multiple injection volume evaluation indicators, the injection effect can be assessed from different dimensions, overcoming the limitations of a single indicator and ensuring a more comprehensive evaluation of cell quality that better meets actual production needs. The optimal solution can be directly determined by the comprehensive score obtained by summing multiple sub-scores, which can screen out the injection adjustment volume that has better overall cell performance, thereby helping to improve the overall performance of the cell.

[0014] In some embodiments, the injection volume evaluation indicators include: average injection volume, injection volume failure rate, and injection volume process capability index.

[0015] The average injection volume directly reflects the overall deviation between the candidate injection volume and the benchmark injection volume, serving as a fundamental indicator for measuring injection accuracy. Quantitative evaluation of this indicator can prevent overall cell performance deviations caused by systematic biases. The rejection rate (the percentage of cells exceeding the acceptable injection volume range) is directly related to production quality and cost. Assessing the rejection rate can prevent defective cells from entering subsequent processes, reducing rework rates and quality risks at the source. The process capability index, by quantifying the ratio of injection volume fluctuation to the acceptable range, reflects the stability and anti-interference capability of the production process. Evaluating this indicator ensures long-term consistency of cell quality. This application's embodiments use these three indicators to measure candidate injection adjustment volumes, enabling the selection of injection adjustment volumes with superior overall cell performance, thereby improving the overall performance of the cells.

[0016] In some embodiments, the liquid-filled cell group includes N cells, where N is a positive integer; obtaining the deviation between the actual liquid-filled volume and the reference liquid-filled volume of the liquid-filled cell group includes: for each cell, calculating the deviation between the actual liquid-filled volume and the reference liquid-filled volume of the cell; calculating the average of the N cell liquid-filled volume deviations to obtain the deviation between the actual liquid-filled volume and the reference liquid-filled volume of the liquid-filled cell group.

[0017] By calculating the electrolyte injection deviation for each cell in a cell group individually, the electrolyte injection fluctuation of a single cell can be accurately captured. By averaging the deviations of N cells, the dispersed individual deviations can be transformed into a group deviation index that represents the overall state of the group. This allows the determination of multiple candidate electrolyte injection adjustment amounts based on the deviations to match the characteristics of the entire group, reducing deviations caused by excessive differences in individual data. As a result, the deviation between the actual electrolyte injection amount and the reference electrolyte injection amount can be determined more accurately, which is beneficial for determining the target electrolyte injection adjustment amount more accurately, thereby improving cell performance.

[0018] In some embodiments, controlling the injection device to inject electrolyte into the battery cell to be injected based on the target injection adjustment amount includes: obtaining a relationship coefficient between the target injection adjustment amount and the injection adjustment amount set by the injection device from a coefficient library; correcting the target injection adjustment amount based on the relationship coefficient to obtain the target injection adjustment amount set by the injection device; and controlling the injection device to inject electrolyte into the battery cell to be injected based on the target injection adjustment amount set by the injection device.

[0019] During the liquid injection process, the actual output liquid injection volume differs from the theoretical setting value due to factors such as mechanical wear, pipeline pressure loss, and sensor sensitivity differences. By introducing a relationship coefficient (reflecting the mapping relationship between the target adjustment amount and the actual response of the equipment), the theoretically calculated target liquid injection adjustment amount can be specifically corrected. This reduces the deviation between the actual output liquid injection volume and the theoretical setting value caused by factors such as mechanical wear, pipeline pressure loss, and sensor sensitivity differences, thus making the actual liquid injection volume injected into the battery cell closer to the required liquid injection volume, which is beneficial to improving the battery cell performance.

[0020] In some embodiments, obtaining the relationship coefficient between the target injection adjustment amount and the injection adjustment amount set by the injection device includes: obtaining from a coefficient library the previous relationship coefficients between the target injection adjustment amount and the injection adjustment amount set by the injection device for Q previously injected cell groups that were injected before the injected cell group; the injection time of the Q previously injected cell groups is the Q cell groups closest to the injection time of the injected cell group; and determining the relationship coefficient between the target injection adjustment amount and the injection adjustment amount set by the injection device based on the Q previous relationship coefficients.

[0021] By selecting the previous coefficients of the Q nearest cell groups, the latest response pattern of the injection equipment can be captured. This allows for accurate determination of the difference between the actual injection volume and the theoretical setting value, caused by factors such as mechanical wear, pipeline pressure loss, and sensor sensitivity differences. Therefore, by using the coefficients of the Q most recent batches, the impact of random errors can be minimized, making the relationship coefficients more stable and providing a reliable basis for subsequent adjustment corrections.

[0022] In some embodiments, the method further includes storing the relationship coefficient between the target injection adjustment volume and the target set injection adjustment volume in a coefficient library.

[0023] By storing the latest relationship coefficients, the next adjustment of the liquid injection volume can be made based on the latest relationship coefficients. This makes the relationship between the set liquid injection adjustment volume and the actual liquid injection adjustment volume more consistent with the state of the liquid injection system. As a result, the actual liquid injection volume injected into the cell is as close as possible to the required liquid injection volume, which is beneficial to improving cell performance.

[0024] In some embodiments, when the deviation is within the acceptable range of the injection volume, the injection device is controlled to inject the battery cell to be injected with liquid according to the reference injection volume.

[0025] If the deviation is within the acceptable range for the amount of electrolyte injected, it means that the actual amount of electrolyte injected into the current electrolyte-injected cell group meets the requirements. Therefore, the electrolyte injection of the cells to be injected can be continued directly based on the benchmark amount of electrolyte injected.

[0026] Secondly, this application also provides a cell liquid injection system, including: a weighing device, a host computer, and a liquid injection device;

[0027] The weighing device is used to weigh each cell in the pre-filled battery cell group to obtain the actual amount of liquid injected into the pre-filled battery cell group, and send the actual amount of liquid injected into the pre-filled battery cell group to the host computer; the host computer is connected to the weighing device and is used to execute the method described in the first aspect; the liquid injection device is connected to the host computer and is used to inject liquid into the battery cell to be injected according to the control signal carrying the target liquid injection adjustment amount sent by the host computer.

[0028] As described above, after the weighing equipment sends the actual liquid injection volume of the liquid-filled battery cell assembly to the host computer, the host computer can determine the deviation between the actual liquid injection volume and the reference liquid injection volume. If the deviation is not within the acceptable liquid injection volume range (which can be the CP range), the host computer can determine multiple candidate liquid injection adjustment volumes based on the deviation. Then, it uses the liquid injection volume evaluation index to evaluate the candidate liquid injection adjustment volumes and obtains the scores corresponding to the candidate liquid injection adjustment volumes. The candidate liquid injection adjustment volume corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment volume. Thus, in this embodiment of the application, when the liquid injection volume deviation is not within the acceptable liquid injection volume range, the liquid injection adjustment volume is no longer determined solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment volumes are determined based on the deviation, and then scores are obtained for these multiple candidate liquid injection adjustment volumes based on the liquid injection volume evaluation index. The candidate liquid injection adjustment volume that meets the preset conditions is selected as the target liquid injection adjustment volume. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0029] Thirdly, this application provides a method for injecting electrolyte into battery cells, comprising: weighing the actual amount of electrolyte injected into the battery cell assembly using a weighing device; obtaining the deviation between the actual amount of electrolyte injected into the battery cell assembly and a reference amount of electrolyte injected via a host computer based on the actual amount of electrolyte injected into the battery cell assembly; if the deviation is not within the acceptable range of the amount of electrolyte injected, determining multiple candidate amount of electrolyte injection adjustment via the host computer based on the deviation; evaluating each candidate amount of electrolyte injection adjustment according to at least one amount of electrolyte injection evaluation index to obtain a score corresponding to the candidate amount of electrolyte injection adjustment; determining the target amount of electrolyte injection adjustment corresponding to the score that meets preset conditions among the multiple scores; and injecting electrolyte into the battery cell to be injected via an injection device according to a control signal carrying the target amount of electrolyte injection sent by the host computer.

[0030] As described above, after the weighing equipment sends the actual liquid injection volume of the liquid-filled battery cell assembly to the host computer, the host computer can determine the deviation between the actual liquid injection volume and the reference liquid injection volume. If the deviation is not within the acceptable liquid injection volume range (which can be the CP range), the host computer can determine multiple candidate liquid injection adjustment volumes based on the deviation. Then, it uses the liquid injection volume evaluation index to evaluate the candidate liquid injection adjustment volumes and obtains the scores corresponding to the candidate liquid injection adjustment volumes. The candidate liquid injection adjustment volume corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment volume. Thus, in this embodiment of the application, when the liquid injection volume deviation is not within the acceptable liquid injection volume range, the liquid injection adjustment volume is no longer determined solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment volumes are determined based on the deviation, and then scores are obtained for these multiple candidate liquid injection adjustment volumes based on the liquid injection volume evaluation index. The candidate liquid injection adjustment volume that meets the preset conditions is selected as the target liquid injection adjustment volume. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0031] Fourthly, this application provides a battery cell liquid injection device, the device comprising:

[0032] The acquisition module is used to obtain the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell assembly;

[0033] The determination module is used to determine multiple candidate injection adjustment amounts based on the deviation when the deviation is not within the acceptable range of injection volume.

[0034] The evaluation and determination module is used to evaluate each candidate injection adjustment volume according to at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume.

[0035] The control module is used to control the injection device to inject liquid into the battery cell to be injected, based on the target injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores.

[0036] Fifthly, this application provides an electronic device, the electronic device comprising: a processor and a memory storing computer program instructions;

[0037] When the processor executes the computer program instructions, it implements the cell liquid injection method as described in the first aspect above, or the cell liquid injection method as described in the third aspect above.

[0038] Sixthly, this application provides a computer-readable storage medium storing computer program instructions that, when executed by a processor, implement the cell electrolyte injection method as described in the first aspect above, or the cell electrolyte injection method as described in the third aspect above.

[0039] In a seventh aspect, this application provides a computer program product in which instructions, when executed by a processor of an electronic device, cause the electronic device to perform the cell liquid injection method as described in the first aspect above, or the cell liquid injection method as described in the third aspect above.

[0040] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0041] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0042] Figure 1 This is a flowchart of a cell electrolyte injection method according to an embodiment of this application;

[0043] Figure 2 This is a flowchart of S101 of one embodiment of this application;

[0044] Figure 3 This is a first flowchart of S103 of an embodiment of this application;

[0045] Figure 4 This is a second flowchart of S103 of an embodiment of this application;

[0046] Figure 5 This is a first flowchart of S104 of an embodiment of this application;

[0047] Figure 6 This is a second flowchart of S104 of an embodiment of this application;

[0048] Figure 7 This is a flowchart of S106 of one embodiment of this application;

[0049] Figure 8 This is a flowchart illustrating the determination of relationship coefficients according to one embodiment of this application;

[0050] Figure 9 This is a schematic diagram of a cell liquid injection system according to another embodiment of this application;

[0051] Figure 10This is a flowchart of a cell liquid injection method according to another embodiment of this application;

[0052] Figure 11 This is a schematic diagram of a cell liquid injection device according to an embodiment of this application;

[0053] Figure 12 This is a schematic diagram of an electronic device according to an embodiment of this application. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0056] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0057] In this application, the term "embodiment" is used to mean that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0058] In the description of the embodiments in this application, the term "and / or" 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 document generally indicates that the preceding and following related objects have an "or" relationship.

[0059] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0060] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0061] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0062] Electrolyte is an important component of battery cells. The amount of electrolyte injected into a battery cell is a key control parameter in battery processing and production. Too much or too little electrolyte will directly affect the battery's lifespan and safety performance.

[0063] Therefore, the amount of electrolyte injected into the battery cell is crucial to the battery's lifespan and safety. Controlling the injection of the appropriate amount of electrolyte into the battery cell to improve its performance is of great significance.

[0064] In related technologies, when adjusting the electrolyte injection volume of a battery cell, a process control range, namely the CPP (Control Process Point) range, is usually set. The CPP range is wider than the CP (Control Point) range. The CP range is the acceptable range or control limit, which refers to the allowable fluctuation range within which the electrolyte injection volume of the battery cell is judged to be acceptable. This range is centered on the target center value (for example, specifying that the optimal electrolyte injection volume is Wg), with a tolerance range (for example, ±1g) above and below it. The corresponding CP range is [W-1, W+1]. As long as the electrolyte injection volume of the battery cell falls within this range, it is a qualified product. Similarly, the CPP range is centered on the target center value (for example, specifying that the optimal electrolyte injection volume is Wg), with a tolerance range (for example, ±2g) above and below it. The corresponding CPP range is [W-2, W+2]. Although the injection volume in this range exceeds the acceptable range (CP range) and is considered non-compliant (NG), the system considers the deviation to be acceptable and can intervene and correct it through the automatic adjustment system.

[0065] In related technologies, the electrolyte injection volume is only adjusted when it falls within the CPP range, and this adjustment is primarily based on the volume deviation. Adjusting the volume in real-time solely based on deviation may miss the optimal adjustment amount that ensures the best cell performance. This is because adjusting the volume based on deviation does not utilize evaluation indicators for assessing the volume. These indicators include: average volume, volume failure rate, and volume process capability index. Adjusting the volume solely based on deviation cannot identify the optimal volume adjustment amount for the best overall cell performance. Furthermore, in related technologies, when the volume fluctuation is significant and the deviation exceeds the CPP range, the lack of scientific prediction and evaluation of the volume adjustment score prevents adjustments from being made.

[0066] Therefore, to solve the above problems and improve cell performance, this application provides a cell liquid injection method and system. In the solution provided in this application, when determining the target liquid injection adjustment amount for the cell to be injected, the deviation between the actual liquid injection amount and the reference liquid injection amount of the already injected cell group is first obtained. If the deviation is not within the acceptable liquid injection amount range (which can be the CP range), multiple candidate liquid injection adjustment amounts can be determined based on the deviation. Then, the candidate liquid injection adjustment amounts are evaluated using a liquid injection amount evaluation index to obtain a score corresponding to the candidate liquid injection adjustment amount. The candidate liquid injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment amount. Thus, in this application embodiment, when the liquid injection amount deviation is not within the acceptable liquid injection amount range, the liquid injection adjustment amount is no longer determined solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment amounts are determined based on the deviation, and then scores for these multiple candidate liquid injection adjustment amounts are obtained based on the liquid injection amount evaluation index. From these, the candidate liquid injection adjustment amount whose score meets the preset conditions is selected as the target liquid injection adjustment amount. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0067] The following describes the cell electrolyte injection method provided in the embodiments of this application. The host computer configured in the cell electrolyte injection process can serve as the execution entity for the method provided in the embodiments of this application.

[0068] In one embodiment, Figure 1 A flowchart of the cell electrolyte injection method is shown, such as... Figure 1 As shown, the method may include the following steps: S101 to S106:

[0069] S101, obtain the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell assembly.

[0070] In S101, the pre-filled cell group can be multiple cells that have already been filled with electrolyte, such as 10 cells, and the reference electrolyte filling amount can be the median value of CP, such as Wg.

[0071] When obtaining the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled cell assembly, the deviation between the actual liquid injection volume and the reference liquid injection volume of each cell in the liquid-filled cell assembly can be calculated separately. By calculating the average value of the liquid injection volume deviations of all cells, the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled cell assembly can be obtained.

[0072] It should be noted that the reason for obtaining the liquid-filled battery cell assembly is to eliminate the problem of large deviations in the liquid-filling volume data of individual cells, thereby improving accuracy.

[0073] S102, determine whether the deviation is within the acceptable range of injection volume.

[0074] In practical applications, the target liquid injection volume of the battery cell can be set as the CP median value. The acceptable range above and below the median value is the CP range. The CP range is the acceptable range or control limit, which refers to the allowable fluctuation range within which the liquid injection volume of the battery cell is judged to be acceptable. This range is centered on the target median value (for example, specifying that liquid injection Wg is optimal), with a tolerance range (for example, ±1g) above and below it. The corresponding CP range is [W-1, W+1]. As long as the liquid injection volume of the battery cell falls within this range, it is a qualified product.

[0075] In this embodiment, the acceptable range for the injection volume can be a CP range, for example, [W-1, W+1]. If the deviation is within the acceptable range, it proves that the actual injection volume meets the acceptable conditions, and no adjustment of the injection volume is needed. Therefore, S106 can be executed: control the injection device to inject the battery cell to be injected according to the reference injection volume. If the deviation is not within the acceptable range, it proves that the actual injection volume does not meet the acceptable conditions, and the injection volume needs to be adjusted. Therefore, S103 is executed.

[0076] S103, based on the deviation, determines multiple candidate injection adjustment amounts.

[0077] If the deviation is not within a preset range, multiple candidate injection adjustment volumes can be determined based on the deviation. For example, this step can determine an allowable deviation range based on the deviation, and then determine multiple candidate injection adjustment volumes within the allowable deviation range.

[0078] It should be noted that in related technologies, when determining the compensation range for the electrolyte injection volume of the battery cell, adjustments are only made when the deviation range is within the CPP range. Adjustments cannot be made for cases with large data fluctuations (e.g., exceeding the CPP range). The CPP range is a process control range or process control limit, which is wider than the CP range. This range is centered on the target center value (e.g., specifying Wg of electrolyte injection as optimal), with a tolerance range (e.g., ±2g) above and below it. The corresponding CPP range is [W-2, W+2]. Although the electrolyte injection volume within this range exceeds the acceptable range (CP range) and is considered non-conforming (NG), the system considers the deviation acceptable and can intervene and correct it through the automatic adjustment system.

[0079] In this embodiment of the application, when the deviation is not within the preset range, multiple candidate liquid injection adjustment amounts can be determined based on the deviation, thereby overcoming the limitation that the liquid injection amount is only adjusted when the deviation is within the CPP range. Furthermore, determining multiple candidate liquid injection adjustment amounts within the allowable deviation range can set a reasonable boundary range for the liquid injection adjustment amount, ensuring that all candidate adjustment amounts are within the range of safe liquid injection for the battery cell, and enabling all candidate adjustment amounts to minimize the negative impact on the battery cell performance.

[0080] S104. For each candidate injection adjustment volume, evaluate the candidate injection adjustment volume according to at least one injection volume evaluation index to obtain the score corresponding to the candidate injection adjustment volume.

[0081] In S104, the evaluation index for liquid injection volume can be at least one of the following: average liquid injection volume, liquid injection volume failure rate, and liquid injection volume process capability index. As an example, to more comprehensively evaluate the overall performance of the battery cell, all three can be included.

[0082] The average injection volume directly reflects the overall deviation between the candidate injection volume and the benchmark injection volume, and is a fundamental indicator for measuring injection accuracy. Quantitative evaluation of this indicator can prevent overall cell performance deviations caused by systematic biases.

[0083] The non-compliance rate of electrolyte injection volume (the percentage of cells exceeding the acceptable electrolyte injection volume range) is directly related to production quality and cost. By assessing the non-compliance rate, defective cells can be prevented from flowing into subsequent processes, reducing rework rate and quality risks from the source.

[0084] The liquid injection volume process capability index reflects the stability and anti-interference ability of the production process by quantifying the ratio of the fluctuation range of liquid injection volume to the qualified range. By evaluating this index, the long-term consistency of cell quality can be ensured.

[0085] In S104, after determining the injection volume evaluation index, the candidate injection adjustment volume can be evaluated based on at least one injection volume evaluation index to obtain the score corresponding to the candidate injection adjustment volume.

[0086] This application embodiment scores the candidate liquid injection adjustment amount according to at least one liquid injection volume evaluation index, which can evaluate the liquid injection effect from different dimensions, break through the limitations of a single index, and ensure that the evaluation of cell quality is more comprehensive and more in line with actual production needs.

[0087] S105, based on the target injection adjustment amount corresponding to the score that meets the preset conditions among multiple scores, controls the injection device to inject liquid into the battery cell to be injected.

[0088] As an example, when controlling the injection device to inject liquid into the battery cell to be injected based on the target liquid injection adjustment amount corresponding to the score that meets the preset conditions among multiple scores, the liquid injection adjustment amount corresponding to the score that meets the preset conditions among multiple scores can be used as the target liquid injection adjustment amount, and then the liquid injection device can be used to control the injection device to inject liquid into the battery cell to be injected.

[0089] For example, the preset condition can be the largest data value; for instance, the candidate injection volume with the highest score can be determined as the target injection volume. The preset condition can also be any one of the top X values; for instance, any one of the X candidate injection volumes with the highest score can be determined as the target injection volume.

[0090] This application embodiment determines the candidate liquid injection adjustment amount that meets the preset conditions as the target liquid injection adjustment amount, which can screen out the liquid injection adjustment amount that has better overall performance of the battery cell, thereby helping to improve the overall performance of the battery cell.

[0091] Based on the scheme defined in S101 to S106 above, it can be understood that in this embodiment, when determining the target liquid injection adjustment amount for the cell to be injected, the deviation between the actual liquid injection amount and the reference liquid injection amount of the already injected cell group is first obtained. If the deviation is not within the acceptable liquid injection amount range (which can be the CP range), multiple candidate liquid injection adjustment amounts can be determined based on the deviation. Then, the candidate liquid injection adjustment amounts are evaluated using the liquid injection amount evaluation index to obtain a score corresponding to the candidate liquid injection adjustment amount. The candidate liquid injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment amount. Thus, in this embodiment, when the liquid injection amount deviation is not within the acceptable liquid injection amount range, the liquid injection adjustment amount is no longer adjusted solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment amounts are determined based on the deviation, and then scores for these multiple candidate liquid injection adjustment amounts are obtained based on the liquid injection amount evaluation index. The candidate liquid injection adjustment amount whose score meets the preset conditions is selected as the target liquid injection adjustment amount. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0092] In one embodiment, the pre-filled battery cell assembly includes N cells, where N is a positive integer. The deviation between the actual liquid filling volume and the reference liquid filling volume of the pre-filled battery cell assembly is obtained based on the average deviation of the liquid filling volume deviations of the N cells and the deviation of the reference liquid filling volume. Figure 2 The process of S101 is shown, as follows: Figure 2 As shown, the process includes the following steps:

[0093] S201, for each cell, calculate the deviation between the actual electrolyte injection volume and the reference electrolyte injection volume. By calculating the electrolyte injection volume deviation for each cell in a cell group individually, the electrolyte injection fluctuation of a single cell can be accurately captured.

[0094] In S201, N cells that have recently completed electrolyte injection can be selected as a group. Taking 10 cells as a group as an example, the actual electrolyte injection volumes of the 10 cells are W1, W2, W3, W4, W5, W6, W7, W8, W9, and W10. The electrolyte injection volume deviation of each cell from the reference electrolyte injection volume W is calculated, resulting in 10 deviations M1, M2, M3, M4, M5, M6, M7, M8, M9, and M10, where M1 = W1 - W, M2 = W2 - W, M3 = W3 - W, M4 = W4 - W, M5 = W5 - W, M6 = W6 - W, M7 = W7 - W, M8 = W8 - W, M9 = W9 - W, and M10 = W10 - W.

[0095] S202, calculate the average value of the electrolyte injection volume deviation of N cells to obtain the deviation between the actual electrolyte injection volume of the injected cell group and the reference electrolyte injection volume. That is, the deviation M = (M1 + M2 + M3 + M4 + M5 + M6 + M7 + M8 + M9 + M10) / 10.

[0096] By averaging the deviations of N cells, the dispersed individual deviations can be transformed into a group deviation index that represents the overall state of the group. This allows the determination of multiple candidate liquid injection adjustment amounts based on the deviations to match the characteristics of the entire group, reducing deviations caused by excessive differences in individual data. As a result, the deviation between the actual liquid injection amount and the reference liquid injection amount can be determined more accurately, which is beneficial for determining the target liquid injection adjustment amount more accurately, thereby improving cell performance.

[0097] In one embodiment, when determining multiple candidate injection adjustment amounts based on deviation, a deviation tolerance range is first determined, and then multiple candidate injection adjustment amounts are determined within the deviation tolerance range. Figure 3 An example of determining multiple candidate injection adjustment volumes is shown, such as Figure 3 As shown, the process includes the following steps:

[0098] S301, Based on the deviation, determine the allowable deviation range.

[0099] In S301, the allowable deviation range is a reasonable boundary range defined based on the requirements of the cell filling process, safety standards, and quality objectives. It represents the deviation between the actual amount of electrolyte injected into the cell assembly and the reference amount of electrolyte injected. The amount of electrolyte adjustment within the allowable deviation range will not negatively affect the performance of the cell. For example, the allowable deviation range can be α1M-α5M.

[0100] S302, within the allowable deviation range, determine multiple candidate injection adjustment amounts.

[0101] Determining multiple candidate liquid injection adjustment amounts within the allowable deviation range allows for setting reasonable boundary ranges for the liquid injection adjustment amounts, ensuring that all candidate adjustment amounts are within the safe liquid injection range for the battery cell, and minimizing the negative impact of all candidate adjustment amounts on the battery cell performance.

[0102] In one embodiment, when determining multiple candidate injection adjustment amounts based on deviation, the multiple candidate injection adjustment amounts can be obtained through a deviation adjustment coefficient. Wherein, Figure 4 Another example of determining multiple candidate injection adjustment volumes is shown, such as Figure 4 As shown, this example may include the following steps:

[0103] S401, obtain multiple deviation adjustment coefficients corresponding to the deviation.

[0104] In S401, multiple deviation adjustment factors can be α1, α2, α3, α4, and α5. As a more specific example, these deviation adjustment factors can be: α1 is 0.5, α2 is 0.75, α3 is 1, α4 is 1.25, and α5 is 1.5.

[0105] S402, within the allowable deviation range, the deviation is adjusted based on multiple deviation adjustment coefficients to obtain multiple candidate injection adjustment amounts.

[0106] Based on multiple deviation adjustment coefficients, the corresponding candidate injection adjustment amounts can be α1M, α2M, α3M, α4M, and α5M.

[0107] By setting a deviation coefficient within the allowable deviation range, a dual constraint condition of "range boundary + coefficient ratio" is formed. On the one hand, it can ensure that all candidate adjustment amounts are within the range of safe electrolyte injection for the battery cell. On the other hand, it can ensure that the multiple candidate electrolyte injection adjustment amounts are always quantified around the core of the deviation, avoiding deviations that may be caused by random values ​​within the range. Moreover, it can make the multiple candidate adjustment amounts as evenly distributed as possible within the allowable deviation range, which is more conducive to screening out the candidate electrolyte injection adjustment amounts that maximize the battery cell performance, thereby making the candidate electrolyte injection adjustment amounts accurately matched with the battery cell.

[0108] In one embodiment, the score corresponding to each candidate injection adjustment volume can be obtained through... Figure 5 The process shown determines, specifically, the process includes the following steps S501 to S502:

[0109] S501, for each candidate injection adjustment volume, determine the candidate injection volume based on the candidate injection adjustment volume and the baseline injection volume.

[0110] In S501, the candidate injection adjustment volumes are α1, α2, α3, α4, and α5, and the baseline injection volume is W. When the candidate injection adjustment volume is α1M, the candidate injection volumes are A1, A2, A3, A4, A5, A6, A7, A8, A9, and A10; when the candidate injection adjustment volume is α2M, the candidate injection volumes are B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10; when the candidate injection adjustment volume is... When the injection volume is α3M, the candidate injection volumes are C1, C2, C3, C4, C5, C6, C7, C8, C9, and C10; when the candidate injection volume is adjusted to α4M, the candidate injection volumes are D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10; when the candidate injection volume is adjusted to α5M, the candidate injection volumes are E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10, as shown in Table 1.

[0111] Table 1

[0112]

[0113] S502, evaluate the candidate injection volume according to at least one injection volume evaluation index, and obtain the score corresponding to the candidate injection adjustment volume.

[0114] In S502, after determining multiple candidate injection volumes, at least one injection volume evaluation index is used to evaluate the multiple candidate injection volumes to obtain a score corresponding to the candidate injection adjustment volume, so as to select the optimal injection volume based on the score.

[0115] Determining the candidate injection volume based on the candidate injection adjustment volume and the baseline injection volume can convert the adjustment volume into the actual injection volume. This allows the subsequent calculation of the score corresponding to the candidate injection adjustment volume based on the injection evaluation index to be directly based on the actual injection volume of the cell, rather than the adjustment range. This facilitates more convenient control of the injection equipment to inject liquid into the cell.

[0116] In one embodiment, the following can be used: Figure 6 The method shown is used to determine the score, such as Figure 6 As shown, Figure 6 An example is shown for calculating the score corresponding to the candidate injection adjustment volume based on the injection evaluation index. This example may include the following steps S601 to S602:

[0117] S601, for each candidate injection volume, evaluate the candidate injection volume according to each injection volume evaluation index to obtain a sub-score for each injection volume evaluation index.

[0118] In S601, there can be multiple evaluation indicators for the liquid injection volume. For example, the evaluation indicators for the liquid injection volume can include at least one of the following: average liquid injection volume (AVG), liquid injection volume non-compliance rate (NG), and liquid injection volume process capability index (CPK). As an example, to more comprehensively evaluate the overall performance of the battery cell, all three can be included.

[0119] The average injection volume (AVG) directly reflects the overall deviation between the candidate injection volume and the baseline injection volume, serving as a fundamental indicator for measuring injection accuracy. Quantitative evaluation using this indicator can prevent overall cell performance deviations caused by systematic biases. In this embodiment, AVG can be the average injection volume deviation M, where M = (M1 + M2 + M3 + M4 + M5 + M6 + M7 + M8 + M9 + M10) / 10. The closer AVG is to 0 (i.e., closer to the CP median), the higher the score, indicating higher overall accuracy of the entire injection volume group.

[0120] The NG (Not Good Rate) rate refers to the percentage of battery cells that exceed the acceptable electrolyte filling range. The NG rate directly impacts production quality and cost. By assessing the NG rate, defective cells can be prevented from entering subsequent processes, reducing rework rates and quality risks at the source. NG rate = (Number of cells exceeding the acceptable range / Total number of cells in the battery pack) × 100%. The acceptable range can be the CP range, for example, [W-1, W+1]. A lower NG rate results in a higher score, indicating more stable electrolyte filling accuracy for that battery pack and a lower risk of defective products in mass production.

[0121] The injection volume CPK (Process Capability Index) is a quantitative indicator used to measure the stability and resistance to fluctuations in the injection production process. Its core is the ratio of the actual injection volume fluctuation range to the preset acceptable range, which determines whether the process can consistently and stably produce qualified battery cells. The calculation formula is as follows:

[0122] CPK = min[(Upper limit of CP - Mean injection volume) / (3 × Standard deviation of injection volume), (Mean injection volume - Lower limit of CP) / (3 × Standard deviation of injection volume)]

[0123] Among them, "CP upper / lower limit" is the upper and lower boundaries of the qualified range, and "injection volume standard deviation" reflects the degree of dispersion of the injection volume fluctuation (the smaller the standard deviation, the weaker the fluctuation).

[0124] The injection volume (CPK) is used to assess the long-term stability of the injection process. The higher the CPK, the higher the score. For example, CPK=1.33 indicates that the process fluctuates less and can stably meet the qualification requirements. The higher the CPK (usually ≥1.33), the better the process resistance to interference, even if there are slight fluctuations in the environment (such as temperature, equipment wear).

[0125] By quantifying the ratio of the fluctuation range of the electrolyte injection volume to the acceptable range, the stability and anti-interference ability of the production process are reflected. By evaluating this indicator, the long-term consistency of cell quality can be ensured. This application uses these three indicators to measure candidate electrolyte injection adjustment volumes, enabling the selection of electrolyte injection adjustment volumes that have a better overall effect on cell performance, thereby improving the overall performance of the cells.

[0126] In this embodiment, for each candidate injection volume, the candidate injection volume is evaluated according to each injection volume evaluation index to obtain a sub-score for each injection volume evaluation index. For example, please refer to Table 1. After calculation, for the groups with candidate injection volumes of A1, A2, A3, A4, A5, A6, A7, A8, A9, and A10, the corresponding sub-scores are AVG1, NG1, and CPK1; for the groups with candidate injection volumes of B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10, the corresponding scores are AVG2 and NG2. The sub-scores are AVG3, NG3, and CPK3 for groups with candidate injection volumes of C1, C2, C3, C4, C5, C6, C7, C8, C9, and C10; AVG4, NG4, and CPK4 for groups with candidate injection volumes of D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10; and AVG5, NG5, and CPK5 for groups with candidate injection volumes of E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10.

[0127] S602 sums up multiple sub-scores to obtain the score corresponding to the candidate injection adjustment volume.

[0128] In S602, the score corresponding to the candidate injection volume is obtained by summing AVG, NG rate, and CPK.

[0129] After obtaining the scores corresponding to the candidate injection volumes, the candidate injection adjustment volumes whose scores meet preset conditions are determined as the target injection adjustment volumes. In this embodiment, the scores can be sorted. As one example, the candidate injection adjustment volume with the highest score is determined as the target injection adjustment volume. As another example, any candidate injection adjustment volume in the TOPX scores can be determined as the target injection adjustment volume.

[0130] For example, please continue to refer to Table 1. For groups with candidate injection volumes of A1, A2, A3, A4, A5, A6, A7, A8, A9, and A10, score 1 = AVG1 + NG1 + CPK1; for groups with candidate injection volumes of B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10, score 2 = AVG2 + NG2 + CPK2; for groups with candidate injection volumes of C1, C2, C3, C4, and C5, ... For groups C6, C7, C8, C9, and C10, score 3 = AVG3 + NG3 + CPK3; for groups with candidate injection volumes D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10, score 4 = AVG4 + NG4 + CPK4; for groups with candidate injection volumes E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10, score 5 = AVG5 + NG5 + CPK5.

[0131] In this embodiment of the application, the candidate injection adjustment amount corresponding to the candidate injection volume with the highest score among scores 1, 2, 3, 4, and 5 can be determined as the optimal injection adjustment amount. For example, if score 4 is the highest, then the candidate injection adjustment amount α4M corresponding to the group with candidate injection volumes of D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10 can be determined as the optimal injection adjustment amount M0.

[0132] It should be noted that when determining the score for candidate injection adjustment amounts, a data range for each indicator can be pre-constructed, and different scores can be assigned to different data ranges according to preset standards. For example, when assigning scores to data ranges, the impact of each indicator on cell performance is considered. Based on the impact of each indicator on cell performance, the data range for each indicator and the corresponding score for each data range are determined. For instance, for AVG, when AVG is less than ±a, the corresponding score is 10 points; when the AVG data range is ±a to ±b, the corresponding score is 9 points…; when AVG is greater than c5, the corresponding score is 0 points. For NG rate, when the NG rate is 0, the corresponding score is 10 points; when the NG rate is 0-d, the corresponding score is 9 points…; when the NG rate is greater than e, the corresponding score is 0 points. For CPK, when CPK is greater than f, the corresponding score is 10 points; when CPK is at fg, the corresponding score is 9 points…; when CPK is less than h, the corresponding score is 0 points, as shown in Table 2.

[0133] Table 2

[0134]

[0135] For example, when scoring the candidate injection adjustment volume, the AVG score, NG rate and CPK score of each candidate injection volume are first determined. The data range to which each indicator score belongs is determined based on the above scores. Then, based on the correspondence between the data range and the score, the score of each indicator is obtained. Finally, the scores of all indicators are summed to obtain the score of each candidate injection volume.

[0136] By evaluating each candidate injection volume using multiple injection volume evaluation indicators, the injection effect can be assessed from different dimensions, overcoming the limitations of a single indicator and ensuring a more comprehensive evaluation of cell quality that better meets actual production needs. The optimal solution can be directly determined by the comprehensive score obtained by summing multiple scores, which can screen out the injection adjustment volume that has better overall cell performance, thereby helping to improve the overall performance of the cell.

[0137] In some embodiments, when controlling the injection device to inject electrolyte into the cell to be injected based on the target injection adjustment amount, the target injection adjustment amount can be corrected using a relationship coefficient, wherein... Figure 7 The process of controlling the liquid injection device to inject liquid into the battery cell to be injected is shown, such as... Figure 7 As shown, the process includes the following steps:

[0138] S701, Obtain the relationship coefficient between the target injection adjustment amount and the injection adjustment amount set in the injection equipment from the coefficient library;

[0139] It should be noted that the reason for introducing the relationship coefficient in this embodiment is that the actual output injection volume of the injection equipment may deviate from the theoretical injection equipment setting value due to factors such as mechanical wear, pipeline pressure loss, and differences in sensor sensitivity. The relationship coefficient is used to represent the correlation between the actual output injection volume of the injection equipment and the injection equipment setting value. The change in the K value represents the change in the environment, that is, the adjustment coefficient adapts to the environment.

[0140] In S701, the coefficient library pre-stores multiple relationship coefficients that represent the correlation between historical injection adjustment volume and injection equipment setting adjustment volume.

[0141] For example, the relationship coefficient is determined based on the ratio between the injection adjustment amount Mn and the injection adjustment amount Sn set by the injection equipment, that is, the injection adjustment amount Kn = Mn / Sn, as shown in Table 3.

[0142] Table 3

[0143]

[0144] It should be noted that in the relevant technologies, when compensating for the liquid injection volume of the battery cells, after determining the deviation between the average liquid injection volume of the already injected battery cell group and the median CP, the battery cell to be injected is injected based on the deviation value. However, the deviation between the actual output liquid injection volume and the theoretical set value caused by factors such as mechanical wear of the injection equipment, pipeline pressure loss, and sensor sensitivity differences is not taken into account. This results in the actual liquid injection volume of the battery cell being inaccurate, which further affects the performance of the battery cell.

[0145] To address the aforementioned issues, a correlation coefficient was introduced to correct the theoretically calculated target injection adjustment amount. This coefficient is stored in a coefficient database, whose data is collected during the actual injection process and then stored in the host computer of the injection procedure.

[0146] Specifically, after a set of battery cells has been injected with electrolyte, the electrolyte injection adjustment amount Sn and the electrolyte injection adjustment amount Mn set by the electrolyte injection equipment can be obtained, and the coefficient can be obtained by calculating the ratio between the two.

[0147] During storage, the host computer records the storage time or injection time, facilitating the subsequent retrieval of the latest stored relationship coefficients from the coefficient library. These coefficients are then used to adjust the injection adjustment amount Mn, resulting in the injection equipment's set injection adjustment amount Sn. This ensures the actual injection amount closely matches the required injection amount, thereby improving cell performance. S702: Based on the relationship coefficients, the target injection adjustment amount is corrected to obtain the target set injection adjustment amount for the injection equipment.

[0148] In step S702, after obtaining the relationship coefficient K between the target injection adjustment amount and the injection equipment setting adjustment amount from the coefficient library, the target injection adjustment amount M0 is corrected using the relationship coefficient K to obtain the target setting injection adjustment amount S0, i.e., S0 = M0 / K. The target setting injection adjustment amount S0 is the actual injection adjustment amount that the injection equipment needs to be set to.

[0149] S703 controls the injection equipment to inject electrolyte into the battery cells to be injected, based on the target setting of the injection adjustment amount.

[0150] In S703, the liquid injection adjustment amount S0 is set based on the corrected target setting, and the liquid injection device is controlled to inject liquid into the battery cell to be injected.

[0151] During the liquid injection process, the actual output liquid injection volume differs from the theoretical setting value due to factors such as mechanical wear, pipeline pressure loss, and sensor sensitivity differences. By introducing a relationship coefficient (reflecting the mapping relationship between the target adjustment amount and the actual response of the equipment), the theoretically calculated target liquid injection adjustment amount can be specifically corrected. This reduces the deviation between the actual output liquid injection volume and the theoretical setting value caused by factors such as mechanical wear, pipeline pressure loss, and sensor sensitivity differences, thus making the actual liquid injection volume injected into the battery cell closer to the required liquid injection volume, which is beneficial to improving the battery cell performance.

[0152] In some embodiments, the process of determining the relationship coefficients, such as Figure 8 As shown, the process includes the following steps:

[0153] S801, retrieve from the coefficient library the previous relationship coefficients between the target liquid injection adjustment amount and the liquid injection adjustment amount set in the liquid injection equipment for the Q previously liquid-injected cell groups that were injected before the liquid-injected cell groups.

[0154] In S801, the injection time of the Q previously injected cell groups is the Q cell groups whose injection time is closest to that of the previously injected cell groups.

[0155] Please refer to Table 3. Taking the three most recent cell groups as examples, the previous relationship coefficients between the target liquid injection adjustment amount of the previously injected cell groups and the liquid injection adjustment amount set in the liquid injection equipment can be K1, K2, and K3.

[0156] S802, based on Q prior relationship coefficients, determines the relationship coefficient between the target injection adjustment amount and the injection equipment setting injection adjustment amount.

[0157] In S802, the relationship coefficient K between the target injection adjustment amount and the injection equipment setting adjustment amount can be determined based on the average of Q previous relationship coefficients, i.e., K = (K1 + K2 + K3) / 3.

[0158] By selecting the previous coefficients of the Q nearest cell groups, the latest response pattern of the injection equipment can be captured. This allows for accurate determination of the difference between the actual injection volume and the theoretical setting value, caused by factors such as mechanical wear, pipeline pressure loss, and sensor sensitivity differences. Therefore, by using the coefficients of the Q most recent batches, the impact of random errors can be minimized, making the relationship coefficients more stable and providing a reliable basis for subsequent adjustment corrections.

[0159] In some embodiments, after obtaining the relationship coefficient between the target injection adjustment amount and the target set injection adjustment amount, the relationship coefficient between the target injection adjustment amount and the target set injection adjustment amount can be stored in a coefficient library.

[0160] By storing the latest relationship coefficients, the next adjustment of the liquid injection volume can be made based on the latest relationship coefficients. This makes the relationship between the set liquid injection adjustment volume and the actual liquid injection adjustment volume more consistent with the state of the liquid injection system. As a result, the actual liquid injection volume injected into the cell is as close as possible to the required liquid injection volume, which is beneficial to improving cell performance.

[0161] The above is a complete description of the cell liquid injection method provided in this application embodiment. In this application embodiment, when determining the target liquid injection adjustment amount of the cell to be injected, the deviation between the actual liquid injection amount and the reference liquid injection amount of the already injected cell group is first obtained. If the deviation is not within the qualified liquid injection amount range (which can be the CP range), multiple candidate liquid injection adjustment amounts can be determined based on the deviation. Then, the candidate liquid injection adjustment amounts are evaluated using the liquid injection amount evaluation index to obtain the score corresponding to the candidate liquid injection adjustment amount. The candidate liquid injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment amount. Thus, in this application embodiment, when the liquid injection amount deviation is not within the qualified liquid injection amount range, when determining the liquid injection adjustment amount, the adjustment is no longer based solely on the deviation, but rather multiple selectable candidate liquid injection adjustment amounts are determined based on the deviation. Then, the scores of these multiple candidate liquid injection adjustment amounts are obtained based on the liquid injection amount evaluation index, and the candidate liquid injection adjustment amount whose score meets the preset conditions is selected as the target liquid injection adjustment amount. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0162] This concludes the explanation of the methods provided in the embodiments of this application.

[0163] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0164] Based on the above-described injection method embodiments, such as Figure 9As shown, this application also provides a cell liquid injection system, including: a weighing device 901, a host computer 902 and a liquid injection device 903;

[0165] Weighing device 901 is used to weigh each cell in the liquid-filled cell group to obtain the actual liquid-filled cell group and send the actual liquid-filled cell group to the host computer 902.

[0166] The host computer 902 is connected to the weighing device 901 and is used to perform the cell liquid injection method described above.

[0167] The liquid injection device 903 is connected to the host computer 902 and is used to inject liquid into the battery cell to be injected according to the control signal sent by the host computer 902 carrying the target liquid injection adjustment amount.

[0168] In one embodiment, the cell liquid injection system further includes: a lower-level machine;

[0169] The lower-level machine is used to control the transmission of each cell in the liquid-filled cell group to the weighing device 901 for weighing.

[0170] In the electrolyte injection process, after a group of cells completes electrolyte injection and leaves the station, the lower-level computer controls each cell to be transferred to the weighing device 901 for weighing. After weighing, the upper-level computer 902 stores the weighing result and calculates the average value of the actual electrolyte injection amount for that group of cells. Taking 10 cells as a group as an example, after calculating the average value, the upper-level computer 902 determines whether the average value is NG (Not Acceptable). If NG, the upper-level computer 902 sends a control signal to the lower-level computer to wait for triggering. If the average value is acceptable, the upper-level computer 902 executes the cell electrolyte injection method described above. After electrolyte injection is completed, the upper-level computer 902 stores the current electrolyte injection adjustment amount, the electrolyte injection equipment setting adjustment amount, and the relationship coefficient between the two into the coefficient library. The electrolyte injection ends. At the same time, the upper-level computer 902 sends a trigger signal to the lower-level computer to continue production of the next group of cells.

[0171] In one embodiment, such as Figure 10 As shown, this application also provides a method for injecting electrolyte into a battery cell, comprising:

[0172] S1001, weigh the actual amount of liquid injected into the liquid-filled battery cell assembly using a weighing device;

[0173] S1002, based on the actual liquid injection volume of the liquid-filled battery cell group, the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell group is obtained through the host computer;

[0174] S1003: Determine whether the deviation is within the acceptable range for injection. If the deviation is not within the acceptable range, execute S1004: Based on the deviation, determine multiple candidate injection adjustment amounts via the host computer. For each candidate injection adjustment amount, evaluate it according to at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment amount. Determine the target injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores.

[0175] S1005, based on the control signal sent by the host computer carrying the target liquid injection adjustment amount, injects liquid into the battery cell to be injected through the liquid injection device.

[0176] If the deviation is within the acceptable range for liquid injection, execute S1006 to control the liquid injection equipment to inject the battery cell to be injected according to the reference liquid injection volume.

[0177] In this embodiment, after the weighing device sends the actual liquid injection volume of the liquid-filled battery cell assembly to the host computer, the host computer can determine the deviation between the actual liquid injection volume and the reference liquid injection volume. If the deviation is not within the acceptable liquid injection volume range (which can be the CP range), the host computer can determine multiple candidate liquid injection adjustment volumes based on the deviation. Then, it uses the liquid injection volume evaluation index to evaluate the candidate liquid injection adjustment volumes and obtains the scores corresponding to the candidate liquid injection adjustment volumes. The candidate liquid injection adjustment volume corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment volume. Thus, in this embodiment, when the liquid injection volume deviation is not within the acceptable liquid injection volume range, the liquid injection adjustment volume is no longer determined solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment volumes are determined based on the deviation, and then scores are obtained for these multiple candidate liquid injection adjustment volumes based on the liquid injection volume evaluation index. The candidate liquid injection adjustment volume that meets the preset conditions is selected as the target liquid injection adjustment volume. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0178] The following combination Figure 9 The overall process of the cell liquid injection system provided in the embodiments of this application is described.

[0179] First, after the battery cell is injected with electrolyte and leaves the station, the lower-level computer controls each battery cell in the injected battery cell group (which can be the N batteries that have recently completed the injection) to be sent to the weighing device 901 for weighing. The weighing device 901 weighs each battery cell in the injected battery cell group to obtain the actual amount of electrolyte injected into the injected battery cell group, and sends the actual amount of electrolyte injected into the injected battery cell group to the upper-level computer 902.

[0180] After calculating the average value of the actual liquid injection volume of the liquid-filled battery cell group, the host computer 902 determines whether the average value is NG. If NG, the host computer 902 sends a control signal waiting to be triggered to the slave computer. If the average value is qualified, the host computer 902 calculates the liquid injection volume deviation between the actual liquid injection volume and the reference liquid injection volume of each of the N cells, obtains the liquid injection volume deviation of the N cells, calculates the average value of the liquid injection volume deviation of the N cells, and obtains the deviation M between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell group.

[0181] After obtaining the deviation between the actual electrolyte injection volume and the reference electrolyte injection volume of the injected battery cell assembly, the host computer 902 determines the allowable deviation range based on the deviation. For example, the allowable deviation range could be α1M-α5M. Simultaneously, it obtains multiple deviation adjustment coefficients corresponding to the deviation, which can be α1, α2, α3, α4, and α5. Within the allowable deviation range, the deviation is adjusted based on these multiple adjustment coefficients to obtain multiple candidate electrolyte injection adjustment amounts, which can be α1M, α2M, α3M, α4M, and α5M.

[0182] After obtaining multiple candidate injection adjustment quantities, the host computer 902 can determine the candidate injection quantity based on each candidate injection adjustment quantity and the baseline injection quantity. The candidate injection adjustment quantities are α1M, α2M, α3M, α4M, and α5M, and the baseline injection quantity is W. When the candidate injection adjustment quantity is α1M, the candidate injection quantities are A1, A2, A3, A4, A5, A6, A7, A8, A9, and A10; when the candidate injection adjustment quantity is α2M, the candidate injection quantities are B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10; when the candidate injection adjustment quantity is α2M, the candidate injection quantities are B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10; when the candidate injection adjustment quantity is α1M, the baseline injection quantity is W. When the volume is α3M, the candidate injection volumes are C1, C2, C3, C4, C5, C6, C7, C8, C9, and C10; when the candidate injection volume adjustment is α4M, the candidate injection volumes are D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10; when the candidate injection volume adjustment is α5M, the candidate injection volumes are E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10.

[0183] For each group of candidate injection volumes, the host computer 902 evaluates multiple groups of candidate injection volumes using the injection volume evaluation indicators: average injection volume (AVG), injection volume failure rate (NG), and injection volume process capability index (CPK). For each group of candidate injection volumes, a score is determined for each candidate injection volume. For example, after calculation, for the groups with candidate injection volumes A1, A2, A3, A4, A5, A6, A7, A8, A9, and A10, the corresponding sub-scores are AVG1, NG1, and CPK1; for the groups with candidate injection volumes B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10, the corresponding sub-scores are AVG2, NG2, and CPK2; for the groups with candidate injection volumes C1, C2, and C... 3. For groups C4, C5, C6, C7, C8, C9, and C10, the corresponding sub-scores are AVG3, NG3, and CPK3; for groups with candidate injection volumes D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10, the corresponding sub-scores are AVG4, NG4, and CPK4; for groups with candidate injection volumes E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10, the corresponding sub-scores are AVG5, NG5, and CPK5.

[0184] Then, the host computer 902 sums the multiple sub-scores to obtain the score corresponding to each group of candidate injection volumes. For example, for groups with candidate injection volumes A1, A2, A3, A4, A5, A6, A7, A8, A9, and A10, score 1 = AVG1 + NG1 + CPK1; for groups with candidate injection volumes B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10, score 2 = AVG2 + NG2 + CPK2; for groups with candidate injection volumes C1, C2, C3, C4, C5, C6, and C... 7. For groups C8, C9, and C10, score 3 = AVG3 + NG3 + CPK3; for groups with candidate injection volumes D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10, score 4 = AVG4 + NG4 + CPK4; for groups with candidate injection volumes E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10, score 5 = AVG5 + NG5 + CPK5.

[0185] Subsequently, as an example, the host computer 902 determines the optimal injection adjustment amount as the candidate injection volume corresponding to the highest score among scores 1, 2, 3, 4, and 5. For instance, if score 4 is the highest, then the optimal injection adjustment amount M0 can be determined as the candidate injection adjustment amount α4M corresponding to the groups with candidate injection volumes D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10.

[0186] After determining the optimal injection adjustment amount M0, the host computer 902 obtains the relationship coefficient K between the target injection adjustment amount and the injection equipment setting adjustment amount from the coefficient library, and uses the relationship coefficient K to correct the target injection adjustment amount M0 to obtain the target setting injection adjustment amount S0, that is, S0=M0 / K.

[0187] Subsequently, the host computer 902 sends a control signal carrying the target liquid injection adjustment amount to the liquid injection device 903. Based on the control signal carrying the target liquid injection adjustment amount sent by the host computer 902, the liquid injection device 903 controls the liquid injection device to inject liquid into the battery cell to be injected.

[0188] After the liquid injection is completed, the host computer 902 stores the liquid injection adjustment amount, the liquid injection equipment setting adjustment amount, and the relationship coefficient between the two into the coefficient library. The liquid injection ends. At the same time, the host computer 902 sends the trigger signal for continued production to the slave computer to trigger the slave computer to continue producing the next set of battery cells.

[0189] The above is the overall process of the cell liquid injection system provided in the embodiments of this application.

[0190] In this embodiment, after the weighing device sends the actual liquid injection volume of the liquid-filled battery cell assembly to the host computer, the host computer can determine the deviation between the actual liquid injection volume and the reference liquid injection volume. If the deviation is not within the acceptable liquid injection volume range (which can be the CP range), the host computer can determine multiple candidate liquid injection adjustment volumes based on the deviation. Then, it uses the liquid injection volume evaluation index to evaluate the candidate liquid injection adjustment volumes and obtains the scores corresponding to the candidate liquid injection adjustment volumes. The candidate liquid injection adjustment volume corresponding to the score that meets the preset conditions among the multiple scores is determined as the target liquid injection adjustment volume. Thus, in this embodiment, when the liquid injection volume deviation is not within the acceptable liquid injection volume range, the liquid injection adjustment volume is no longer determined solely based on the deviation. Instead, multiple selectable candidate liquid injection adjustment volumes are determined based on the deviation, and then scores are obtained for these multiple candidate liquid injection adjustment volumes based on the liquid injection volume evaluation index. The candidate liquid injection adjustment volume that meets the preset conditions is selected as the target liquid injection adjustment volume. Therefore, in this embodiment of the application, in determining the target liquid injection adjustment amount, in addition to the deviation, the score obtained based on the liquid injection volume evaluation index is also referenced, thereby breaking through the limitation that the liquid injection volume is only adjusted when the deviation is within the CPP range; and making it possible to obtain a battery cell with better performance indicators when liquid injection is finally performed based on the target liquid injection adjustment amount.

[0191] Based on the above-described injection method embodiments, such as Figure 11 As shown, this application also provides a battery cell liquid injection device. This battery cell liquid injection device can be installed in a host computer. The battery cell liquid injection device 1100 includes:

[0192] The acquisition module 1101 is used to acquire the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell assembly;

[0193] The determination module 1102 is used to determine multiple candidate injection adjustment amounts based on the deviation when the deviation is not within the acceptable range of injection volume.

[0194] The evaluation module 1103 is used to evaluate each candidate injection adjustment volume according to at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume.

[0195] The control module 1104 is used to control the injection device to inject liquid into the battery cell to be injected, based on the target injection adjustment amount corresponding to the score that meets the preset conditions among multiple scores.

[0196] Based on the above-described injection method embodiments, such as Figure 12 As shown, this application provides an electronic device, which includes: a processor 1201 and a memory 1202 storing computer program instructions;

[0197] When the processor 1201 executes computer program instructions, it implements the cell electrolyte injection method described above.

[0198] In one embodiment, this application provides a computer-readable storage medium storing computer program instructions, which, when executed by a processor, implement the cell electrolyte injection method described above.

[0199] Based on the above-described liquid injection method embodiments, this application provides a computer program product. When the instructions in the computer program product are executed by the processor of an electronic device, the electronic device performs the cell liquid injection method as described above.

[0200] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.

[0201] The functional blocks shown in the above block diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. Programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0202] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0203] The foregoing flowcharts and / or block diagrams describing the method for determining the open-circuit voltage of a battery, the battery management system, and the power-consuming device according to embodiments of this application have described various aspects of this application. It should be understood that each block in the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to create a machine such that these instructions, executable by the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowcharts and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by dedicated hardware performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0204] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for injecting electrolyte into a battery cell, characterized in that, include: Obtain the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell assembly; If the deviation is not within the acceptable range for injection volume, multiple candidate injection adjustment volumes are determined based on the deviation. For each candidate liquid injection adjustment amount, the candidate liquid injection adjustment amount is evaluated according to at least one liquid injection amount evaluation index to obtain a score corresponding to the candidate liquid injection adjustment amount. The liquid injection amount evaluation index is an index used to evaluate the degree of influence of liquid injection amount on cell performance. Based on the target injection adjustment amount corresponding to the score that meets the preset conditions among the multiple scores, the injection device is controlled to inject liquid into the battery cell to be injected. The determination of multiple candidate injection adjustment amounts based on the deviation includes: Based on the aforementioned deviation, the allowable deviation range is determined; Obtain multiple deviation adjustment coefficients corresponding to the deviation; Within the allowable deviation range, the deviation is adjusted based on multiple deviation adjustment coefficients to obtain multiple candidate injection adjustment amounts.

2. The method according to claim 1, characterized in that, For each candidate injection adjustment volume, the candidate injection adjustment volume is evaluated according to at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume, including: For each candidate injection adjustment volume, a candidate injection volume is determined based on the candidate injection adjustment volume and the baseline injection volume; The candidate injection volume is evaluated based on at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume.

3. The method according to claim 2, characterized in that, The injection volume evaluation index is multiple. The evaluation of the candidate injection volume based on at least one injection volume evaluation index to obtain a score corresponding to the candidate injection adjustment volume includes: For each candidate injection volume, the candidate injection volume is evaluated according to each injection volume evaluation index to obtain a sub-score for each injection volume evaluation index; The scores of the multiple sub-scores are summed to obtain the score corresponding to the candidate injection adjustment volume.

4. The method according to claim 3, characterized in that, The evaluation indicators for injection volume include: average injection volume, injection volume non-compliance rate, and injection volume process capability index.

5. The method according to claim 1, characterized in that, The pre-filled battery cell assembly comprises N cells, where N is a positive integer; obtaining the deviation between the actual liquid filling volume and the reference liquid filling volume of the pre-filled battery cell assembly includes: For each cell, calculate the deviation between the actual liquid injection volume and the reference liquid injection volume of the cell; Calculate the average value of the liquid injection volume deviations of the N cells to obtain the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-injected cell group.

6. The method according to claim 1, characterized in that, The step of controlling the injection device to inject electrolyte into the battery cell to be injected, based on the target injection adjustment amount corresponding to the score that meets the preset conditions among multiple scores, includes: Obtain the relationship coefficient between the target injection adjustment volume and the injection adjustment volume set in the injection equipment from the coefficient library; The target injection adjustment amount is corrected based on the relationship coefficient to obtain the target injection adjustment amount of the injection equipment; Based on the target, the liquid injection adjustment amount is set, and the liquid injection device is controlled to inject liquid into the battery cell to be injected.

7. The method according to claim 6, characterized in that, The relationship coefficient between obtaining the target injection adjustment volume and the injection adjustment volume set in the injection equipment includes: From the coefficient library, obtain the previous relationship coefficients between the target liquid injection adjustment amount and the liquid injection adjustment amount set in the liquid injection equipment for the Q previously liquid-injected cell groups that were injected before the liquid-injected cell group; the liquid injection time of the Q previously liquid-injected cell groups is the Q cell groups closest to the liquid injection time of the liquid-injected cell group. Based on Q of the aforementioned previous relationship coefficients, the relationship coefficient between the target injection adjustment amount and the injection adjustment amount set in the injection equipment is determined.

8. The method according to claim 6 or 7, characterized in that, The method further includes: Store the relationship coefficient between the target injection adjustment volume and the target set injection adjustment volume in the coefficient library.

9. The method according to any one of claims 1-7, characterized in that, The method further includes: If the deviation is within the acceptable range for the injection volume, the injection equipment is controlled to inject the battery cell to be injected with liquid according to the reference injection volume.

10. A cell electrolyte injection system, characterized in that, include: Weighing equipment, host computer, and liquid injection equipment; The weighing device is used to weigh each cell in the liquid-filled cell group to obtain the actual liquid-filled amount of the liquid-filled cell group, and send the actual liquid-filled amount of the liquid-filled cell group to the host computer. The host computer is connected to the weighing device and is used to execute the method according to any one of claims 1-9; The liquid injection device is connected to the host computer and is used to inject liquid into the battery cell to be injected according to the control signal sent by the host computer carrying the target liquid injection adjustment amount.

11. A method for injecting electrolyte into a battery cell, characterized in that, include: The actual amount of electrolyte injected into the electrolyte-filled battery cell assembly is determined by weighing using a weighing device. Based on the actual liquid injection volume of the liquid-filled battery cell group, the deviation between the actual liquid injection volume and the reference liquid injection volume of the liquid-filled battery cell group is obtained through the host computer. If the deviation is not within the acceptable range for the injected liquid volume, the host computer determines multiple candidate injected liquid adjustment amounts based on the deviation. For each candidate injected liquid adjustment amount, it is evaluated according to at least one injected liquid volume evaluation index to obtain a score corresponding to the candidate injected liquid adjustment amount. The injected liquid volume evaluation index is used to evaluate the degree of influence of the injected liquid volume on the cell performance. The target injected liquid adjustment amount corresponding to the score that meets the preset conditions among the multiple scores is determined. According to the control signal carrying the target liquid injection adjustment amount sent by the host computer, the liquid injection device injects liquid into the battery cell to be injected. The determination of multiple candidate injection adjustment amounts based on the deviation includes: Based on the aforementioned deviation, the allowable deviation range is determined; Obtain multiple deviation adjustment coefficients corresponding to the deviation; Within the allowable deviation range, the deviation is adjusted based on multiple deviation adjustment coefficients to obtain multiple candidate injection adjustment amounts.

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