Battery production system and battery production method

Abstract

The invention relates to the technical field of battery production, and discloses a battery production system and a battery production method.The battery production method comprises the steps that a raw material pretreatment module is used for conducting pretreatment preparation on positive and negative electrode active materials, electrolyte and a battery shell; the method specifically comprises the steps of mixing, coating, drying, rolling and slitting of a positive electrode material and a negative electrode material, accurate preparation and water and oxygen removal treatment of an electrolyte, and cleaning and drying of a battery shell. And revolutionary improvement of the battery production process is realized. The method has the core beneficial effects that a battery product with ultrahigh consistency, excellent reliability, ultra-long cycle life and top safety performance is produced, meanwhile, the production efficiency is greatly improved, the comprehensive cost is reduced, a perfect quality tracing system is established, and a powerful technical guarantee is provided for large-scale and high-quality battery manufacturing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery production, more particularly to a battery production system and a battery production method. BACKGROUND

[0002] With the rapid development of electric vehicles, portable electronic devices and energy storage power stations, the demand for high-performance secondary batteries such as lithium-ion batteries has surged, and the requirements for their energy density, cycle life, safety and consistency have become increasingly stringent. Battery manufacturing is a complex process involving multiple precision processes, and the performance of the final product is highly dependent on the quality of raw materials, the accuracy of process control, and the stability of the production environment.

[0003] Currently, mainstream battery production lines are typically composed of multiple relatively independent process units, such as slurry preparation, coating, rolling, slitting, winding / stacking, liquid injection, packaging, formation, and capacity detection. However, this segmented production mode has the following significant problems: 1. Due to large fluctuations in process parameters, the equipment of each process unit is independently controlled, making it difficult to achieve precise linkage and stable control throughout the entire process, resulting in low consistency and yield.

[0004] 2. Electrode sheets and electrolytes are extremely sensitive to moisture and oxygen. The existing production line is difficult to achieve effective ultra-low humidity or inert atmosphere protection throughout the entire process, such as after drying the electrode sheet, assembling the battery cell, and injecting liquid. The invasion of moisture (>100 ppm) and oxygen can cause side reactions, consume active lithium, and result in low first coulomb efficiency, gas production, increased internal resistance, shortened cycle life, and even safety hazards.

[0005] 3. Injection precision and infiltration: traditional injection methods have limitations in precision, temperature control, and vacuum degree, resulting in inaccurate injection volume, uneven electrolyte distribution, and insufficient infiltration, affecting battery performance and consistency. Therefore, the present application provides a battery production system and a battery production method. SUMMARY

[0006] In order to overcome the above-mentioned defects of the prior art, the present application provides a battery production system and a battery production method to solve the problems existing in the background art.

[0007] The present application provides the following technical solution: a battery production system composed of five modules, namely a raw material pretreatment module, a battery assembly module, an electrolyte injection module, a finished product detection module, and a central control unit, comprising the following contents: Raw material pretreatment module: used for pretreatment of positive and negative active materials, electrolyte and battery shell; including mixing, coating, drying, rolling and slitting of positive and negative materials, accurate preparation and water / oxygen removal of electrolyte, and cleaning and drying of battery shell; Battery assembly module: used for assembling the pretreated positive and negative sheets and diaphragm into electrode assembly, and completing the process of entering the shell and pre-packaging; Electrolyte injection module: used for accurately and quantitatively injecting the pretreated electrolyte into the battery shell with assembled electrode assembly under dry environment or inert atmosphere protection; Finished product detection module: used for detecting the performance of the battery after injection and final packaging; including open circuit voltage, internal resistance, capacity, self-discharge rate test, appearance inspection, air tightness test and safety performance sampling; Central control unit: used for centralized monitoring and coordination of the operation of the above four modules; receiving sensor data of each module, real-time analysis, feedback and control according to preset process parameters, realizing automatic and intelligent scheduling of production process, ensuring the continuity of production process and the consistency of product quality, and recording production data for traceability analysis.

[0008] Further, the battery assembly module includes an electrode assembly forming unit, which uses a winding or laminating process to assemble the positive and negative sheets and diaphragm into a bare battery cell, and realizes the connection of the tab and current collector through laser welding.

[0009] Further, the electrolyte injection module is equipped with a vacuum injection system, i.e. a constant temperature liquid storage tank for maintaining the electrolyte temperature at 25±2℃; a high-precision metering pump for controlling the injection amount error ≤±0.5%; the battery interior is vacuumed to ≤10Pa before injection.

[0010] Further, the finished product detection module includes a cycle life test unit, which is qualified at 25℃ constant temperature environment with 1C charge and discharge rate cycle ≥500 times, and capacity retention rate ≥80%.

[0011] Further, the central control unit integrates the MES system, real-time collects the process parameters (temperature / pressure / vacuum degree) of each module, dynamically adjusts the production rhythm and generates a unique traceability code.

[0012] Further, the drying process of the raw material pretreatment module uses dehumidified air with dew point ≤-40℃, and the water content of the positive and negative sheets is controlled to ≤100ppm.

[0013] A battery production method of a battery production system, implemented in the battery production system of claim 6, characterized in that it includes the following contents: S1, first mix the positive and negative active materials with conductive agent and binder into a slurry, continuously mix with a twin-screw extruder, control the viscosity at 3000-5000 mPa·s, verify the dispersion uniformity with a doctor blade fineness meter, confirm that it meets the standard, then evenly coat the slurry on the metal foil current collector, dry with dehumidified air with a dew point of ≤-40℃, roll the electrode sheet, set five progressive rolling passes, roll the electrode sheet to the standard thickness, then cut into the specified size, at the same time, mix lithium salt with organic solvent in a glove box in an inert atmosphere, dehydrate and deoxygenate to a moisture content of ≤10 ppm, clean the battery case with ultrasonic waves, then blow dry nitrogen to remove residual moisture from the surface; S2, assemble the positive electrode sheet, separator and negative electrode sheet into a bare cell according to the winding or stacking process, ensure that the positive and negative electrode sheets are edge-aligned during assembly, connect the tabs and current collectors by laser welding, load the bare cell into a dry housing, weld the cover plate and reserve the liquid injection port, complete the pre-sealing, transfer the pre-packaged battery to an inert atmosphere chamber, vacuum to ≤10 Pa; the electrolyte is maintained at 25±2℃ in a constant temperature storage tank, a high-precision metering pump (error ≤±0.5%) is used to inject a pre-set amount of electrolyte into the battery, stand for 10 minutes after injection to allow the electrolyte to fully soak, seal the liquid injection port, and complete the airtight packaging by laser welding; S3, perform the first charge and discharge on the battery to form a stable SEI film, detect the open circuit voltage, internal resistance and capacity (0.2C discharge), screen out voltage abnormal products, detect the leakage rate with a helium detector (≤0.01 Pa·m³ / s), manually check for appearance defects, and at 25℃ in a constant temperature environment, the capacity retention rate is ≥80% after 1C charge and discharge cycles ≥500 times, sample 5% of each batch for overcharge, needle puncture and extrusion tests, and require no fire or explosion; S4, real-time collection of sensor data from each module, dynamic adjustment of equipment parameters, generation of a unique traceability code, binding of production data, triggering of alarms and isolation of problem batteries for abnormal data, and ensuring product consistency Technical effects and advantages of the application: The application controls the slurry dispersion uniformity, has low moisture / oxygen content, accurately controls the thickness of the electrode sheet, and forms a stable SEI film, which lays a foundation for the long service life of the battery, and the mandatory life verification requires that each battery has a capacity retention rate of ≥80% after 500 cycles at 25℃ and 1C rate, which directly ensures that the batteries meet the basic life requirements, is beneficial to the consistency of the product, and can predict the actual use state of the product, and can provide more stable performance.

[0014] The application contains mandatory safety performance sampling (≥5% batches are sampled for overcharge, needle puncture, and extrusion test) through a finished product detection module, requires "no fire and explosion", directly verifies the safety bottom line of the battery, and effectively suppresses the root causes of safety hazards such as gas production and thermal runaway through extremely low water and oxygen content (pole piece ≤100ppm, electrolyte ≤10ppm, inert atmosphere assembly / liquid injection).

[0015] The application realizes revolutionary improvement of the battery production process through highly automated, intelligent, and integrated module design, combined with precise process parameter control and strict and comprehensive detection standards. The core beneficial effect is that the battery products with ultra-high consistency, excellent reliability, ultra-long cycle life, and top safety performance are produced, and the production efficiency is greatly improved, the comprehensive cost is reduced, and a perfect quality traceability system is established, which provides strong technical support for large-scale and high-quality battery manufacturing. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The figure is a process flow diagram of the application. DETAILED DESCRIPTION

[0017] The technical solutions in the application will be described clearly and completely in combination with the drawings in the application. In addition, the forms of each structure described in the following embodiments are only examples, and the battery production system and the battery production method involved in the application are not limited to each structure described in the following embodiments. All other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the application.

[0018] REFERENCE Figure 1 The application provides a battery production system composed of five modules of raw material pretreatment module, battery assembly module, electrolyte injection module, finished product detection module, and central control unit, including the following contents. The raw material pretreatment module is used for pretreatment of positive and negative active materials, electrolyte, and battery shell; specifically including mixing, coating, drying, rolling, and slitting of positive and negative materials, accurate preparation and water and oxygen removal treatment of electrolyte, and cleaning and drying of battery shell; The battery assembly module is used for assembling the pretreated positive and negative sheets and diaphragm into an electrode assembly, and completing the shell entering and pre-packaging process; The electrolyte injection module is used for accurately and quantitatively injecting the pretreated electrolyte into the battery shell with assembled electrode assembly in a dry environment or under inert atmosphere protection; Product detection module: for performance testing of the battery after liquid injection and final packaging; including open circuit voltage, internal resistance, capacity, self-discharge rate test, as well as appearance inspection, air tightness test and safety performance sampling; Central control unit: for centralized monitoring and coordination of the operation of the above four modules; receiving sensor data from each module, analyzing, feeding back and controlling in real time according to the preset process parameters, realizing automatic and intelligent scheduling of the production process, ensuring the continuity of the production process and the consistency of the product quality, and recording the production data for traceability analysis, the five core modules (preprocessing, assembly, liquid injection, detection, control) are highly integrated and automatically operated, the central control unit realizes intelligent scheduling, reduces the waiting and transfer time between processes, and automatic scheduling reduces manual intervention and improves efficiency.

[0019] Among them, the battery assembly module includes an electrode assembly forming unit, the forming unit adopts a winding type or a laminated type process to assemble the positive and negative electrode sheets and the separator into a bare battery cell, and realizes the connection of the tab and the current collector through laser welding.

[0020] Among them, the electrolyte injection module is equipped with a vacuum injection system, that is, a constant temperature liquid storage tank is used to maintain the electrolyte temperature at 25±2℃; a high-precision metering pump is used to control the injection amount error ≤±0.5%; the battery interior is vacuumed to ≤10Pa before injection.

[0021] Among them, the product detection module contains a cycle life test unit, which is qualified at 25℃ constant temperature environment with 1C charge-discharge rate cycle ≥500 times, capacity retention rate ≥80%.

[0022] Among them, the central control unit integrates the MES system, real-time collects the process parameters (temperature / pressure / vacuum degree) of each module, dynamically adjusts the production rhythm and generates a unique traceability code, the central control unit generates a unique traceability code for each battery or batch, binds all key production data (process parameters, test results, operation records, etc.), and the real-time collected massive data is used for process monitoring, quality analysis, process optimization and problem root tracing. Abnormal data triggers alarm and isolates problem battery to prevent defect diffusion and provide basis for continuous improvement: complete and traceable production data is a valuable asset for quality analysis, process optimization and product iteration and upgrading.

[0023] Among them, the drying process of the raw material preprocessing module uses dehumidified air with dew point ≤-40℃, and the water content of the positive and negative electrode sheets is controlled to ≤100ppm.

[0024] A battery production method of a battery production system, implemented in the battery production system of claim 6, characterized in that it comprises the following contents: S1, first mix the positive and negative active materials with the conductive agent and the binder into a slurry, continuously mix using a double screw extruder, control the viscosity at 3000-5000 mPa·s, verify the uniformity of dispersion by a doctor blade fineness meter, after confirming that the standard is met, uniformly coat the slurry on the metal foil current collector, dry with dehumidified air with a dew point of ≤-40℃, roll the electrode sheet, set five progressive rolling passes, roll the electrode sheet to the standard thickness, and then cut it into electrode sheets of the specified size, at the same time, mix the lithium salt with the organic solvent in a glove box in an inert atmosphere, treat to remove water and oxygen until the moisture content is ≤10 ppm, clean the battery case with ultrasonic waves, and then blow dry nitrogen to remove residual moisture from the surface; S2, assemble the positive electrode sheet, the separator, and the negative electrode sheet into a bare battery cell according to the winding or stacking process, ensure that the positive and negative electrode sheets are edge-aligned during assembly, connect the tabs and the current collector by laser welding, place the bare battery cell into a dry housing, weld the cover plate and reserve a liquid injection port, complete the pre-sealing, transfer the pre-sealed battery to an inert atmosphere chamber, and vacuum to ≤10 Pa; maintain the electrolyte at 25±2℃ in a constant-temperature storage tank, inject a pre-set amount of electrolyte into the battery through a high-precision metering pump (error ≤±0.5%), let it stand for 10 minutes after injection to allow the electrolyte to fully soak, seal the liquid injection port, and complete the airtight packaging by laser welding; S3, perform the first charge and discharge on the battery to form a stable SEI film, detect the open circuit voltage, internal resistance, and capacity (0.2C discharge), screen out voltage abnormal products, detect the leakage rate (≤0.01 Pa·m³ / s) with a helium detector, manually check for appearance defects, and at 25℃ in a constant-temperature environment, the capacity retention rate ≥80% after 1C charge and discharge cycling for ≥500 times is considered to be qualified, sample 5% of each batch for overcharge, needle puncture, and extrusion tests, and no fire or explosion is required; S4, real-time collection of sensor data from each module, dynamic adjustment of equipment parameters, generation of a unique traceability code, binding of production data, triggering of alarms and isolation of problem batteries for abnormal data, and ensuring product consistency.

[0025] Finally, a few points should be noted: first, in the description of the present application, it should be noted that unless otherwise specified and limited, the terms "mounting", "connection", "connection" should be broadly understood, which can be mechanical connection or electrical connection, or the communication between two elements, or direct connection, "up", "down", "left", "right" and the like are only used to indicate the relative positional relationship, when the absolute position of the described object changes, the relative positional relationship may change; Secondly: the present application discloses only the structures involved in the embodiments of the present disclosure in the drawings, other structures can refer to the usual design, and in the case of no conflict, the same embodiment and different embodiments of the present application can be combined with each other; Finally: the above only for the preferred embodiments of the present application, and not for limiting the present application, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application, should be included in the scope of protection of the present application.

Claims

1. A battery production system, comprising five modules: a raw material pretreatment module, a battery assembly module, an electrolyte injection module, a finished product inspection module, and a central control unit, characterized in that: Includes the following: Raw material pretreatment module: used for pre-processing and preparing positive and negative electrode active materials, electrolyte and battery shell; specifically including mixing, coating, drying, rolling and slitting of positive and negative electrode materials, precise preparation and dehydration and deoxygenation treatment of electrolyte, and cleaning and drying of battery shell; Battery assembly module: used to assemble the pre-processed positive and negative electrode sheets and separators into electrode assemblies, and complete the shelling and pre-packaging processes; Electrolyte injection module: used to accurately and quantitatively inject pre-treated electrolyte into the battery housing of the assembled electrode assembly in a dry environment or under the protection of an inert atmosphere; Finished product testing module: used to perform performance testing on batteries after filling and final packaging; Including open circuit voltage, internal resistance, capacity, self-discharge rate test, as well as appearance inspection, air tightness test and safety performance spot check; Central Control Unit: Used to centrally monitor and coordinate the operation of the above four modules; receive sensor data from each module, perform real-time analysis, feedback and control according to preset process parameters, realize automation and intelligent scheduling of the production process, ensure the continuity of the production process and the consistency of product quality, and record production data for traceability analysis.

2. A battery production system according to claim 1, characterized in that: The battery assembly module includes an electrode assembly forming unit, which uses a winding or lamination process to assemble positive and negative electrode sheets and separators into bare battery cells, and connects the tabs and current collectors through laser welding.

3. A battery production system according to claim 2, characterized in that: The electrolyte injection module is equipped with a vacuum injection system, that is, a constant temperature liquid storage tank is used to maintain the electrolyte temperature at 25±2°C; a high-precision metering pump is used to control the injection volume error to ≤±0.5%; before injection, the battery interior is vacuumed to ≤10Pa.

4. A battery production system according to claim 3, characterized in that: The finished product inspection module includes a cycle life test unit. It is qualified if the cycle is ≥500 times at a 1C charge and discharge rate under a constant temperature environment of 25°C and the capacity retention rate is ≥80%.

5. A battery production system according to claim 4, characterized in that: The central control unit is integrated with the MES system to collect the process parameters (temperature / pressure / vacuum degree) of each module in real time, dynamically adjust the production rhythm and generate a unique traceability code.

6. A battery production system according to claim 5, characterized in that: The drying process of the raw material pretreatment module uses dehumidified air with a dew point of ≤-40°C, and the moisture content of the positive and negative electrode sheets is controlled to ≤100ppm.

7. A battery production method of a battery production system, implemented in the battery production system according to claim 6, characterized in that: Includes the following: S1. First, the positive and negative electrode active materials are mixed with the conductive agent and the binder to form a slurry, and a twin-screw extruder is used for continuous mixing. The viscosity is controlled at 3000-5000mPa·s. The dispersion uniformity is verified by a scraper fineness meter. After confirming that it meets the standard, the slurry is evenly coated on the metal foil current collector, dried with dehumidified air with a dew point of ≤-40°C, and the pole piece is rolled. By setting five passes of progressive rolling, the pole piece is rolled to a thickness that meets the standard, and then cut into pole pieces of specified size. At the same time, in an inert atmosphere glove box, the lithium salt and the organic solvent are mixed in proportion, and the water content is ≤10ppm after dehydration and deoxygenation treatment. The battery shell is ultrasonically cleaned and then purged with dry nitrogen until there is no residual moisture on the surface; S2. Assemble the positive electrode sheet, diaphragm, and negative electrode sheet into a bare cell using a winding or stacking process. During assembly, ensure that the edges of the positive and negative electrode sheets are aligned. Connect the tabs and current collectors by laser welding, place the bare cell into a dry casing, weld the cover plate and reserve a liquid injection port to complete pre-sealing, transfer the pre-packaged battery to an inert atmosphere chamber, and evacuate to ≤10Pa. Maintain the electrolyte at 25±2°C in a constant temperature liquid storage tank, and inject a preset amount of electrolyte into the battery through a high-precision metering pump (error ≤±0.5%). After injection, let it stand for 10 minutes to allow the electrolyte to fully infiltrate, seal the liquid injection port, and complete the airtight packaging by laser welding. S3. Perform the first charge and discharge on the battery to form a stable SEI film. Test the open circuit voltage, internal resistance, and capacity (0.2C discharge). Screen out products with abnormal voltage. Use a helium detector to detect the leakage rate (≤0.01 Pa·m³ / s). Manually inspect for appearance defects. Under a constant temperature of 25°C, perform 1C charge and discharge cycles for ≥500 times with a capacity retention rate of ≥80% to qualify. 5% of the battery is sampled from each batch and subjected to overcharge / puncture / extrusion tests. No fire or explosion is required. S4. Real-time collection of sensor data from each module, dynamic adjustment of equipment parameters to generate a unique traceability code bound to production data, abnormal data triggers an alarm and isolates the problem battery to ensure product consistency.

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