Lithium battery code scanning, weighing and liquid injection method and system

Abstract

The invention discloses a lithium battery code scanning, weighing and liquid injection method and system, belongs to the technical field of lithium ion batteries, and solves the problems that existing lithium battery liquid injection operation steps are tedious, and battery cell production data are difficult to track according to battery bar codes. Comprising the following steps: initializing a liquid injection system, carrying out first-time code scanning on a single battery cell before primary liquid injection, weighing, storing data before primary liquid injection into a database, executing primary liquid injection, weighing after carrying out primary liquid injection on the single battery cell, associating the data after primary liquid injection with a battery cell code, storing into the database, and executing a formation process. According to the method, the battery cell is subjected to first-time code scanning and weighing before primary liquid injection, and the battery cell code and the primary pre-weighing are stored in the database for inquiring the primary pre-weighing data in the subsequent secondary variable liquid injection process, so that the problem of failure of secondary liquid injection caused by loss of the battery cell code data due to other factors in the actual production process of the battery cell can be effectively avoided; the yield of battery cell production is improved, and the production cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium-ion batteries and relates to a lithium battery scanning, weighing and liquid filling method and system. Background Art

[0002] In the battery production process, the amount of electrolyte injected into the battery is an important indicator of battery performance. Different amounts of electrolyte in each battery will lead to inconsistent battery capacity, affecting battery cycle performance and battery safety. Therefore, during the injection process, it is necessary to calculate the injection volume of each battery and bind it to the battery barcode for easy query and traceability.

[0003] The electrolyte injection process in lithium battery injection systems is typically divided into two steps: primary and secondary injection. The primary injection is a constant injection of 90% of the total injection volume, while the secondary injection is a constant injection of 10% of the total injection volume. However, due to factors in the production process, the actual quantitative injection method can lead to a discrepancy between the actual electrolyte volume of the battery cell and the standard electrolyte volume, affecting the long-term stability and reliability of the battery. Insufficient electrolyte volume can lead to insufficient wetting of some active particles, increased interfacial impedance, and deterioration of capacity and cycle life. Excessive electrolyte volume can cause excessive gas production, resulting in interfacial problems, and increased side reactions, leading to low initial efficiency of the entire battery.

[0004] Variable injection can ensure the long-term stability and reliability of the battery by precisely controlling the secondary injection volume, while effectively reducing electrolyte loss and achieving the purpose of cost saving. Prior art, such as the invention patent with application publication number CN109326764A, discloses a method for accurately controlling the electrolyte content of lithium-ion batteries, including a variable injection method for primary injection and secondary injection. The primary injection is specifically performed by injecting the battery cell, setting the injection volume to m4, weighing the battery cell after the injection is completed, recording the weight as M3, and then calculating the primary variable injection volume to m5 and injecting the liquid. The above barcode Ln, injection weighing, and injection volume data: M1, M2, M3, m1, m3, m4, and m5 are saved in the database; the secondary injection is specifically performed by scanning and weighing the battery cell after the battery cell is formed and left to stand, recording the weight as M4, and retrieving the data saved in the primary injection according to the battery cell barcode Ln, calculating the secondary injection volume to m6, and completing the secondary variable injection for each battery cell one by one. While this method achieves extreme precision in cell injection volume through a second variable refill, while also reducing overall electrolyte usage and lowering production costs, its operation is cumbersome and requires multiple calculations of cell weight and injection volume. This method has low injection efficiency when dealing with production lines with large production capacity and a large number of cells. Furthermore, because it is not integrated with digital control methods, multiple data entries exist in a single cell code database, making it impossible to accurately track individual cell production data. When the number of cells is large, traditional battery barcode control can lead to duplicate codes, resulting in data errors. Summary of the Invention

[0005] The technical solution of the present invention is used to solve the problems that the existing lithium battery filling operation steps are cumbersome and it is difficult to track the battery cell production data according to the battery barcode.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] A lithium battery scanning, weighing and filling method comprises the following steps:

[0008] S1. Initialize the injection system, scan and weigh a single battery cell for the first time before injection, save the data before injection to the database, and perform injection once;

[0009] S2. Weigh a single battery cell after filling it once, associate the data after filling it once with the battery cell code, save it to the database, and execute the formation process;

[0010] S3. Scan and weigh a group of battery cells twice before the second injection. Generate a bracket number corresponding to the battery cell code of each battery cell, associate it with the data before the first injection, and save it to a local temporary table. Remove redundant data and execute the second injection process.

[0011] S4. Weigh the battery cell after secondary injection, and save the data after secondary injection into the database.

[0012] The present invention performs an initial barcode scanning and weighing of the battery cell before primary liquid injection, and saves the battery cell code and the primary weight to a database for querying the primary weight data in a subsequent secondary variable liquid injection process. This can effectively avoid the problem of secondary liquid injection failure caused by cell code data loss due to other factors in the actual production process of the battery cell, thereby improving the battery cell production qualification rate and reducing production costs. At the same time, the data before and after the primary liquid injection and before and after the secondary liquid injection are directly written into the database, and the database is updated in real time according to the progress of the liquid injection process, providing accurate data support for subsequent processes and reducing errors caused by manual intervention.

[0013] Furthermore, the step of saving the data before the injection into the database in S1 is as follows:

[0014] When the register address value of the previous heavy interaction signal is 0, it is determined that the battery cell scanning is abnormal and the battery cell with abnormal scanning is automatically removed;

[0015] When the register address value of the pre-recharge interaction signal is 1, the pre-filling data of a single battery cell is read and saved in the local database. The register address value of the pre-recharge interaction signal is restored to 0, and the injection mechanism is controlled to perform a single injection on the battery cell transported to the injection station.

[0016] Furthermore, the data before the first injection includes the first weight, the bracket number, the battery core code and the electronic scale number.

[0017] The present invention eliminates battery cells with abnormal code scanning before and after the liquid injection process based on judgment logic, thereby ensuring the production quality of battery cells, improving the code scanning environment, and significantly improving the success rate of equipment code scanning.

[0018] Furthermore, the step S2 of associating the data after one injection with the cell code and saving it to the database is as follows:

[0019] When the register address value of the first post-reaction signal is 1, the data after the first injection of a single battery cell is read, the battery cell code is associated with the bracket number, and saved to the local database. After the reading is completed, the register address value of the first post-reaction signal is restored to 0, and the battery cell is transported to the formation process.

[0020] Furthermore, the data after one injection includes injection result, one pre-weight, one post-weight, injection volume, injection deviation, bracket number, common field row number and common field station number.

[0021] Furthermore, a bracket number is generated corresponding to the battery cell code of each battery cell in S3, and is associated with the data before injection and saved in a local temporary table. Specifically:

[0022] When the storage address of the cell code is 1, read the cell code information and secondary front weight data of the current serial cell. If the cell code information is normal, generate the bracket number, query the primary front weight according to the cell code, insert the data into the temporary table, and restore the storage address of the cell code to 0;

[0023] If the cell code information is abnormal, generate a virtual cell code and a bracket number, continue to generate the bracket number, query the previous weight according to the cell code, insert data into the temporary table, and restore the storage address of the cell code to 0.

[0024] Furthermore, the removal of redundant data in S3 is specifically as follows:

[0025] The time data of the first front weight, second front weight, battery cell code, bracket number, electronic scale number, and second front weight are saved in a temporary table; when the storage address value of the second front weight interaction signal is 1, the bracket number is generated cyclically and incrementally. If the data volume of the temporary table exceeds the threshold, it is sorted in descending order by the scanning time, and the scanning time passTime of the threshold data is obtained and recorded. The data in the temporary table that is less than passTime is deleted, and the bracket number and first front weight data are imported into the PLC; if the data volume of the temporary table does not exceed the threshold, the bracket number is directly imported into the PLC.

[0026] The present invention designs a loop algorithm to cyclically write the bracket number of the PLC specified address to avoid bracket number overflow and retain only the latest data, effectively solving the problem of battery cell bracket number overflow caused by the maximum value of the register's 16-bit storage capacity, reducing storage redundancy and improving query efficiency.

[0027] Furthermore, the step of saving the data after the second injection to the database in S4 is as follows:

[0028] When the register address value of the bracket number semaphore is 1, read the bracket number of the current battery cell to determine whether the bracket number is valid. If valid, read the secondary injection data of the current battery cell and save it to the local database. After the reading is completed, loop to the next battery cell until all battery cells are cycled and the register address value of the bracket number semaphore is restored to 0. If invalid, directly restore the register address value of the bracket number semaphore to 0.

[0029] Furthermore, the data after the second injection includes the second post-weight, bracket number, injection result, common field row number, common field station number, first front weight, second front weight, secondary variable injection volume, total injection volume and injection deviation value.

[0030] The present invention also provides a lithium battery scanning, weighing and filling system, including a primary filling, scanning and weighing module and a secondary variable filling, scanning and weighing module;

[0031] The one-time liquid injection scanning weighing module includes:

[0032] The pre-filling unit is used to initialize the filling system, scan and weigh a single battery cell for the first time before the first filling, save the pre-filling data to the database, and perform the first filling;

[0033] The post-primary injection unit is used to weigh a single battery cell after the first injection, associate the post-primary injection data with the battery cell code, save it to the database, and execute the formation process;

[0034] The secondary variable liquid injection scanning weighing module includes:

[0035] The pre-secondary filling unit is used to scan and weigh a group of battery cells twice before the secondary filling. A bracket number is generated corresponding to the cell code of each battery cell, which is associated with the pre-primary filling data and saved in a local temporary table. Redundant data is removed and the secondary filling process is executed.

[0036] The post-secondary filling unit is used to weigh the battery cell after the secondary filling and save the post-secondary filling data to the database.

[0037] The advantages of the present invention are:

[0038] (1) The present invention scans and weighs the battery cell for the first time before the first injection, and saves the battery cell code and the weight before the first injection into the database for the subsequent second variable injection process to query the weight before the first injection data. This can effectively avoid the problem of the battery cell code data being lost due to other factors during the actual production process, resulting in the failure of the second injection, thereby improving the qualified rate of battery cell production and reducing production costs. At the same time, the data before and after the first injection and before and after the second injection are directly written into the database. The database is updated in real time according to the injection process, providing accurate data support for subsequent processes and reducing errors caused by manual intervention.

[0039] (2) The present invention designs a loop algorithm to cyclically write the bracket number of the PLC specified address to avoid bracket number overflow and retain only the latest data. It effectively solves the problem of battery cell bracket number overflow caused by the maximum value of the register's 16-bit storage capacity being 32767, reduces storage redundancy, and improves query efficiency.

[0040] (3) Based on the judgment logic, the present invention eliminates battery cells with abnormal code scanning before and after the liquid injection process, thereby ensuring the production quality of the battery cells, improving the code scanning environment, and significantly improving the success rate of equipment code scanning. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a flow chart of a lithium battery scanning, weighing and filling method according to the first embodiment of the present invention;

[0042] Figure 2 This is a flow chart of scanning and weighing before liquid injection in Example 1 of the present invention;

[0043] Figure 3 This is a flow chart of weighing after a single injection in Example 1 of the present invention;

[0044] Figure 4 This is a flow chart of generating bracket number information before secondary liquid injection according to the first embodiment of the present invention;

[0045] Figure 5 This is a flowchart of removing redundant data according to the first embodiment of the present invention;

[0046] Figure 6 This is a flow chart of weighing after secondary liquid injection according to the first embodiment of the present invention. DETAILED DESCRIPTION

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0048] The technical solution of the present invention is further described below with reference to the accompanying drawings and specific embodiments:

[0049] Example 1

[0050] like Figure 1 Specifically, a lithium battery scanning, weighing and filling method is disclosed, comprising the following steps:

[0051] S1. Initialize the injection system, scan and weigh a single battery cell for the first time before injection, save the data before injection to the database, and perform injection.

[0052] After baking, standard battery cells undergo a primary injection process. The injection system launches the primary injection host computer software. The system checks the host computer's connection to the PLC, local database, and production MES status. If the connection is abnormal, a prompt message appears. After the software is launched, the threads for pre-injection weighing, primary injection, and post-injection weighing are initiated.

[0053] In response to the battery cell to be filled with liquid arriving at the scanning and weighing station, the scanning device and the weighing device receive the scanning and weighing signal sent by the controller, scan and weigh the single battery cell for the first time respectively, and record the data before liquid filling, which includes the weight before filling, the bracket number, the battery cell code and the electronic scale number; wherein the weight before filling is the weighing data before filling, the bracket number is the bracket number of the pallet for transporting the battery cell, and the battery cell code serves as the unique identification code of the battery cell in subsequent production processes.

[0054] Before the first injection, the first front weight, bracket number, battery core code, electronic scale number and the first front weight interaction signal are respectively stored in the data block of the PLC specified address. Specifically, the storage address of the first front weight is DB3.434, the storage address of the bracket number is DB3.438, the storage address of the battery core code is DB3.452, the storage address of the electronic scale number is DB3.440, and the storage address of the first front weight interaction signal is DB3.0; wherein, the first front weight interaction signal is an interaction signal in response to the upper computer before the first injection.

[0055] like Figure 2 As shown, after the first scan and weighing of a single battery cell is completed, it is necessary to determine whether the interactive signal of the host computer before the first injection is responded to by the host computer, and then determine whether to save the data before the first injection of the single battery cell to the database and whether to perform the first injection process, specifically:

[0056] When the value of the register address DB3.0 of the pre-heavy interaction signal is 0, the PLC determines that the battery cell code scanning is abnormal and automatically removes the battery cell with abnormal code scanning to ensure the battery cell production quality.

[0057] When the value of the register address DB3.0 of the pre-primary recharge interaction signal is 1, the host computer software reads the pre-primary recharge data of a single battery cell from the PLC and saves it to the local database. After reading, it restores the register address DB3.0 of the pre-primary recharge interaction signal to 0. Based on the pre-primary recharge data of a single battery cell, the PLC controls the recharge mechanism deployed at the recharge station to perform the primary recharge on the battery cell transported to the recharge station.

[0058] In this embodiment, based on the above judgment logic, the battery cells with abnormal code scanning can be initially eliminated before the first liquid filling process to ensure the quality of battery cell production, and the data before the first liquid filling of the current battery cell is saved in the first battery cell production table BeforWeight_First in the local database.

[0059] S2. Weigh a single battery cell after filling it once, associate the data after the filling with the battery cell code, save it to the database, and execute the formation process.

[0060] After the primary filling process, the weighing equipment performs a post-filling weighing on the individual battery cells transported to the weighing station and records the post-filling data. This post-filling data includes the filling result, pre-filling weight, post-filling weight, refilling volume, refilling deviation, bracket number, common field row number, and common field station number. The post-filling weight specifically refers to the post-filling weighing data. The filling result, pre-filling weight, post-filling weight, refilling volume, refilling deviation, bracket number, common field row number, common field station number, and post-filling interaction signal are stored in a data block designated by the PLC. Specifically, taking a single battery cell as an example, the storage address of the liquid injection result of the battery cell is DB3.168.3, the storage address of the first weight is DB3.170, the storage address of the second weight is DB3.174, the storage address of the liquid replenishment amount is DB3.178, the storage address of the liquid replenishment deviation amount is DB3.182, the storage address of the bracket number is DB3.186, the row number storage address of the public field storage location is DB3.44, the station number storage address is DB3.46, and the storage address of the second weight interaction signal is DB3.4. Among them, the second weight interaction signal is the interaction signal of the upper computer after the first injection. Before and after the first injection, some data are re-stored in the addresses of different DB blocks (such as the first weight data and the bracket number data), but it does not affect the production process and data processing.

[0061] like Figure 3 As shown, it is necessary to determine whether the interactive signal of the host computer responds to the host computer after one injection, and then determine whether to associate the data after one injection of a single battery cell with the battery cell code and whether to save it to the database, specifically:

[0062] When the value of the register address DB3.4 of the post-primary recharge interaction signal is 1, the host computer software reads the post-primary recharge data of a single cell from the PLC's DB block, associates the cell code with the bracket number, and saves it to the local database. After reading, it restores the register address DB3.4 of the post-primary recharge interaction signal to 0. The cell leaves the current weighing station and the PLC equipment controlling the primary recharge process and is transported to the next formation process.

[0063] In this embodiment, when the value of the register address DB3.4 of the post-weighing interactive signal is 1, it means that the battery cell has been weighed once, and the post-weighing data is saved to the specified DB block. The host computer can read the data and associate the battery cell code according to the bracket number, and save the data after the first injection to the second battery cell production table AfterWeight_First in the local database; when the value of the register address DB3.4 of the post-weighing interactive signal is 0, the host computer does not read the data; in this embodiment, the signal quantity is read cyclically by the host computer software at intervals of 100 milliseconds; in this embodiment, if there are multiple identical bracket number data when the bracket number is associated with the battery cell code, the bracket number data with the latest production date is associated with the battery cell code. The data in the second battery cell production table AfterWeight_First is used to query, count, export, and upload battery cell data to the MES system after the first injection process. The above processes all require interactive operations with this production table.

[0064] S3. Before the second injection, a group of battery cells are scanned and weighed for the second time. A bracket number is generated corresponding to the battery cell code of each battery cell. After being associated with the data before the first injection, it is saved in a local temporary table, and redundant data is removed to execute the second injection process.

[0065] In this embodiment, the liquid injection system includes a primary liquid injection scanning and weighing system and a secondary variable liquid injection scanning and weighing system, which are respectively deployed on the host computers of the primary liquid injection process and the secondary liquid injection process to complete the automatic control functions of their respective processes.

[0066] After the primary injection process, the battery cell is continuously filled with approximately 90% of the total injection volume. After the primary injection process is complete, the formation process is carried out. This process passes through a high-temperature aging chamber, allowing the electrolyte to penetrate the electrodes, participating in chemical reactions and converting chemical energy into electrical energy. After the formation process is complete, the battery cell undergoes a secondary injection process, with a constant injection volume of approximately 10% of the total injection volume. The injection system activates the secondary variable injection host computer software, which sequentially checks the connection status of the control device PLC, the local database, and the production MES host computer. If any connection is abnormal, the host computer software interface displays a prompt message. After the software is launched, the pre-secondary injection weighing, secondary injection, and post-secondary injection weighing threads are initiated.

[0067] In the first injection process, after associating the battery cell code according to the bracket number, the complete first-time post-weight data is saved to the database, and the bracket number of the first injection process is automatically generated by the PLC program; in the second injection process, the bracket number needs to be generated by the host computer program and written into the PLC program DB block, and the bracket number of the first injection process and the bracket number of the second injection process are not associated.

[0068] In this embodiment, 12 battery cells are taken as a group of battery cells, and the battery code storage addresses of the 12 battery cells are DB37.58, DB37.88, DB37.118, DB37.148, DB37.178, DB37.208, DB37.238, DB37.268, DB37.298, DB37.328, DB37.358, and DB37.388, respectively. The secondary pre-registration addresses of the 12 battery cells are DB38.50, DB38.60, DB38.70, DB38.80, DB38.90, DB38.100, DB38.110, DB38.120, DB38.130, DB38.140, DB38.150, and DB38.160, respectively.

[0069] Further, if Figure 4 As shown, it is necessary to determine whether the interactive signal of the host computer before the second injection responds to the host computer, and then determine whether to generate a bracket number corresponding to the cell code of a single cell and whether to associate the data before the first injection and save it to the local temporary table. The battery cell with serial number 1 is used as an example for explanation:

[0070] When the value of the cell code's storage address DB37.782 is 1, read the cell code information and secondary front weight data of the current serial cell. If the cell code information is normal, generate a bracket number, query the front weight once according to the cell code, insert data into the temporary table (TrymRecord table), and restore the cell code's storage address DB37.782 value to 0; if the cell code information is abnormal, generate a virtual cell code and generate a bracket number, continue to generate the bracket number, query the front weight once according to the cell code, insert data into the temporary table (TrymRecord table), and restore the cell code's storage address DB37.782 value to 0.

[0071] In this embodiment, a normal cell code is 24 bits. When the cell code information is abnormal, the cell code is read as ERROR, and a 24-bit virtual cell code is generated for the abnormal cell code for querying and counting abnormal cell data.

[0072] In this embodiment, the cell code of each cell in a group of cells is read one by one, the local database associated with the cell code is queried for the pre-weight data (m), and the bracket number (t) is generated according to the bracket number generation algorithm. The data is then written to the PLC designated addresses in sequence according to the cell sequence number. For example, the pre-weight data (m1) and bracket number (t1) of cell sequence number 1 are stored in the PLC at the following addresses: DB37.9012 and DB37.9032. Each cell is read and imported into the PLC in a loop. After all the data for a group of cells is processed, the host computer writes 0 to the PLC register address DB37.782 to restore the cell code scanning completion signal.

[0073] Further, if Figure 5 As shown, the time data of the primary front weight, secondary front weight, battery cell code, bracket number, electronic scale number, and secondary front weight are saved in a temporary table (TrymRecord table). Since the maximum storage value of a 16-bit register in a PLC is an integer of 32767, the bracket number generated by the design of this embodiment is cyclically changed between 1 and 30,000. By saving the latest 10,000 battery cell data and eliminating redundant data in the register, the uniqueness of the bracket number in the temporary table is guaranteed, specifically:

[0074] When the storage address value of the secondary pre-repeated interaction signal is 1, the bracket number is generated cyclically and incrementally between 1 and 30,000. If the data volume of the temporary table (TrymRecord table) exceeds 10,000, it is sorted in descending order by the scanning time, and the scanning time passTime of the 10,000th data is obtained and recorded. The data in the temporary table (TrymRecord table) that is less than passTime is deleted, and the bracket number and the primary pre-repeated data are imported into the PLC; if the data volume of the temporary table (TrymRecord table) does not exceed 10,000, the bracket number is directly imported into the PLC.

[0075] In this embodiment, a temporary table is created to store the first-time weight data (m), the carriage number (t), the cell code, the scan time, and other elements, with the carriage number as the primary key. Because the PLC stores integers up to 16 bits, to maintain the uniqueness of the carriage number, the above program design ensures that the carriage number is generated cyclically between 1 and 30,000 and deletes redundant data.

[0076] In this embodiment, the cell codes in a group of battery cells are cyclically extracted in sequence of serial numbers in S3, the primary front weight data of the corresponding cell code is queried from the production table according to the cell code, the primary front weight and the bracket number are written into the PLC specified address, the control device calculates the secondary liquid injection volume, and the liquid injection device completes the secondary liquid injection process.

[0077] The secondary variable injection process is as follows: the primary pre-weight data is recorded as M1, and the secondary pre-weight data is recorded as M2. At this time, the actual primary injection volume m1 = M2-M1, and the estimated secondary injection volume m2 = Mg-m1, where Mg is the total liquid retention volume for a single battery cell. Data such as M1, m2, and the bracket number are written into the control system's PLC. The PLC calculates the secondary injection volume, and the injection system completes the secondary variable injection process, achieving precise control of the injection volume.

[0078] S4. Weigh the battery cell after secondary injection and save the secondary injection data to the database. Specifically:

[0079] After the secondary variable injection process is completed, a weighing device is used to perform post-secondary injection weighing to obtain post-secondary injection data. This post-secondary injection data includes the post-secondary weight, bracket number, injection result, common field row number, common field station number, pre-primary weight, pre-secondary weight, secondary variable injection volume, total injection volume, and injection deviation value. Specifically, the post-secondary weight refers to the post-secondary injection weighing data. The bracket number, injection result, row number, station number, pre-primary weight, pre-secondary weight, post-secondary weight, secondary variable injection volume, total injection volume, injection deviation value, and bracket number signal are stored in a data block at a designated address on the PLC. Specifically, taking the battery cell with serial number 1 in a group of battery cells as an example, the storage address of the bracket number is DB47.3388, the storage address of the injection result is DB47.3360.4, the storage address of the row number is DB47.3362, the storage address of the station number is DB47.3366, the storage address of the first front weight is DB47.3368, the storage address of the second front weight is DB47.3372, the storage address of the second rear weight is DB47.3376, the storage address of the secondary variable injection amount is DB47.3380, the storage address of the total injection amount is DB3.178, the storage address of the injection deviation value is DB3.182, and the storage address of the bracket number signal is DB3.6.

[0080] Further, if Figure 6 As shown, it is necessary to determine whether the interactive signal of the host computer responds to the host computer after the second injection, and then determine whether to save the data after the second injection to the battery production table in the database, specifically:

[0081] When the register address DB3.6 value of the bracket number semaphore is 1, the upper computer software reads the bracket number of the current serial cell from the DB block of the PLC to determine whether the bracket number is valid. If valid, the secondary injection data of the current serial cell is read and saved to the local database. After the reading is completed, the battery cell with the next serial number is cycled until all serial cells are cycled and the register address DB3.6 value of the bracket number semaphore is restored to 0; if invalid, the register address DB3.6 value of the bracket number semaphore is directly restored to 0.

[0082] Based on the lithium battery scanning weighing and filling method provided by the present invention, the battery cell production filling data is stored in the third battery cell production table (AW_Second table) of the local database, and the battery cell production filling data is quickly queried and quickly exported in batches. The battery cell production filling result data is uploaded to the production MES in real time to realize the visualization and controllability of the production process. This embodiment provides a group of 12 battery cells for comparison with the required quantitative filling volume of 46g±3g to check the difference between the filling volume and the battery cell specifications. After the variable filling, the battery fluctuates at 46g±1, and the battery consistency is significantly improved. The results are shown in Table 1 below:

[0083] Table 1: Filling data of a group of batteries

[0084]

[0085]

[0086] This embodiment scans and weighs the battery cell before the first injection, and saves the battery cell code and pre-first weight data to the battery cell production table in the database, allowing the pre-first weight data to be queried before the second injection in the subsequent secondary variable injection process. This method effectively avoids the problem of secondary injection failure caused by the loss of battery cell code data due to other factors during the actual production process, significantly improving production efficiency. The design of a tray bracket number algorithm and the use of secondary variable injection enable the system to accurately control the secondary injection volume, reduce electrolyte loss, effectively save costs, and effectively play a role in improving the long-term stability and reliability of the battery.

[0087] The production line of this embodiment has a full production capacity of 320,000 units per day. The original method of quantitative injection was to maintain a liquid volume of 46g for each battery cell, consuming 14.72 tons of electrolyte per day. After changing to secondary variable injection, the electrolyte loss is about 13.11 tons per day. Calculated based on the electrolyte price of RMB 25,000 per ton, the annual savings reach (14.72-13.11)*25,000*365=14,791,250. The liquid volume of the battery cell with quantitative injection fluctuates within 46g±3, and the battery after variable injection fluctuates within 46g±1, and the battery consistency is significantly improved. This method can automatically eliminate batteries with poor injection, effectively preventing defective products from entering the market, and ensuring product quality and customer satisfaction. Through the technical innovation and optimization of the above-mentioned injection method, not only the efficiency and accuracy of battery pack electrical performance detection and analysis are improved, but also important contributions are made to the improvement of the intelligence and automation level of the battery pack manufacturing industry.

[0088] The present invention also discloses a lithium battery scanning, weighing and filling system using the above method, comprising a primary filling, scanning and weighing module and a secondary variable filling, scanning and weighing module; the primary filling, scanning and weighing module and the secondary variable filling, scanning and weighing module are respectively deployed on the host computers of the primary filling process and the secondary filling process, for completing automatic control of their respective processes.

[0089] The one-time liquid injection scanning weighing module includes:

[0090] The pre-filling unit is used to initialize the filling system, scan and weigh a single battery cell for the first time before the first filling, save the pre-filling data to the database, and perform the first filling;

[0091] The post-primary injection unit is used to weigh a single battery cell after the first injection, associate the post-primary injection data with the battery cell code, save it to the database, and execute the formation process.

[0092] The secondary variable liquid injection scanning weighing module includes:

[0093] The pre-secondary filling unit is used to scan and weigh a group of battery cells twice before the secondary filling. A bracket number is generated corresponding to the cell code of each battery cell, which is associated with the pre-primary filling data and saved in a local temporary table. Redundant data is removed and the secondary filling process is executed.

[0094] The post-secondary filling unit is used to weigh the battery cell after the secondary filling and save the post-secondary filling data to the database.

[0095] In this embodiment, the single-filling scanning and weighing module interacts with the PLC signal quantity to read the data such as the front weight, battery cell code, rear weight, filling volume, filling results, etc. in real time and save them in the local database; the system module interface displays the above filling data in real time, and displays the qualified number, NG number, qualified rate, and total output of the single-filling products in real time.

[0096] In this embodiment, the secondary variable liquid injection scanning and weighing module interacts with the PLC in real time, reads the secondary front weight and battery cell code, and associates the primary front weight data according to the battery cell code; by calculating the secondary variable liquid injection volume, the bracket number is automatically generated according to the algorithm model, and the relevant data is imported into the PLC to complete the secondary variable liquid injection process; the system displays the qualified number, NG number, qualified rate, and total output of the secondary liquid injection products in real time.

[0097] In addition, the injection system is equipped with the query and export function of the first and second injection data, and is equipped with the real-time uploading of the battery cell production injection result data to the production MES, realizing the visualization and controllability of the battery cell injection production process.

[0098] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A lithium battery scanning, weighing and filling method, characterized in that: The following steps are involved: S1. Initialize the injection system, scan and weigh a single battery cell for the first time before injection, save the data before injection to the database, and perform injection once; S2. Weigh a single battery cell after filling it once, associate the data after filling it once with the battery cell code, save it to the database, and execute the formation process; S3. Scan and weigh a group of battery cells twice before the second injection. Generate a bracket number corresponding to the battery cell code of each battery cell, associate it with the data before the first injection, and save it to a local temporary table. Remove redundant data and execute the second injection process. S4. Weigh the battery cell after secondary injection, and save the data after secondary injection into the database.

2. A lithium battery scanning, weighing and filling method according to claim 1, characterized in that: The specific steps of saving the data before injection into the database in S1 are as follows: When the register address value of the previous heavy interaction signal is 0, it is determined that the battery cell scanning is abnormal and the battery cell with abnormal scanning is automatically removed; When the register address value of the pre-recharge interaction signal is 1, the pre-filling data of a single battery cell is read and saved in the local database. The register address value of the pre-recharge interaction signal is restored to 0, and the injection mechanism is controlled to perform a single injection on the battery cell transported to the injection station.

3. A lithium battery scanning, weighing and filling method according to claim 2, characterized in that: The data before the first injection includes the first weight, the bracket number, the battery core code and the electronic scale number.

4. A lithium battery scanning, weighing and filling method according to claim 1, characterized in that: The data after one injection is associated with the cell code and saved in the database as described in S2: When the register address value of the first post-reaction signal is 1, the data after the first injection of a single battery cell is read, the battery cell code is associated with the bracket number, and saved to the local database. After the reading is completed, the register address value of the first post-reaction signal is restored to 0, and the battery cell is transported to the formation process.

5. A lithium battery scanning, weighing and filling method according to claim 4, characterized in that: The data after one injection includes injection result, one pre-weight, one post-weight, injection amount, injection deviation, bracket number, common field row number and common field station number.

6. A lithium battery scanning, weighing and filling method according to claim 1, characterized in that: The cell code of each cell in S3 generates a corresponding bracket number, which is associated with the data before injection and saved in a local temporary table. Specifically: When the storage address of the cell code is 1, read the cell code information and secondary front weight data of the current serial cell. If the cell code information is normal, generate the bracket number, query the primary front weight according to the cell code, insert the data into the temporary table, and restore the storage address of the cell code to 0; If the cell code information is abnormal, generate a virtual cell code and a bracket number, continue to generate the bracket number, query the previous weight according to the cell code, insert data into the temporary table, and restore the storage address of the cell code to 0.

7. A lithium battery scanning, weighing and filling method according to claim 6, characterized in that: The removal of redundant data in S3 is specifically as follows: The time data of the first front weight, second front weight, battery cell code, bracket number, electronic scale number, and second front weight are saved in a temporary table; when the storage address value of the second front weight interaction signal is 1, the bracket number is generated cyclically and incrementally. If the data volume of the temporary table exceeds the threshold, it is sorted in descending order by the scanning time, and the scanning time passTime of the threshold data is obtained and recorded. The data in the temporary table that is less than passTime is deleted, and the bracket number and first front weight data are imported into the PLC; if the data volume of the temporary table does not exceed the threshold, the bracket number is directly imported into the PLC.

8. A lithium battery scanning, weighing and filling method according to claim 1, characterized in that: The specific steps of saving the data after the second injection to the database in S4 are as follows: When the register address value of the bracket number semaphore is 1, read the bracket number of the current battery cell to determine whether the bracket number is valid. If valid, read the secondary injection data of the current battery cell and save it to the local database. After the reading is completed, loop to the next battery cell until all battery cells are cycled and the register address value of the bracket number semaphore is restored to 0. If invalid, directly restore the register address value of the bracket number semaphore to 0.

9. A lithium battery scanning, weighing and filling method according to claim 8, characterized in that: The data after the secondary injection includes the secondary post-weight, bracket number, injection result, common field row number, common field station number, primary front weight, secondary front weight, secondary variable injection volume, total injection volume and injection deviation value.

10. A lithium battery scanning, weighing and filling system, characterized in that: It includes a primary liquid injection scanning and weighing module and a secondary variable liquid injection scanning and weighing module; The one-time liquid injection scanning weighing module includes: The pre-filling unit is used to initialize the filling system, scan and weigh a single battery cell for the first time before the first filling, save the pre-filling data to the database, and perform the first filling; The post-primary injection unit is used to weigh a single battery cell after the first injection, associate the post-primary injection data with the battery cell code, save it to the database, and execute the formation process; The secondary variable liquid injection scanning weighing module includes: The pre-secondary filling unit is used to scan and weigh a group of battery cells twice before the secondary filling. A bracket number is generated corresponding to the cell code of each battery cell, which is associated with the pre-primary filling data and saved in a local temporary table. Redundant data is removed and the secondary filling process is executed. The post-secondary filling unit is used to weigh the battery cell after the secondary filling and save the post-secondary filling data to the database.

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