Ferrophosphorus bare cell recovery processing method and system based on intelligent sorting

Abstract

The invention belongs to the technical field of waste lithium ion battery recycling and processing, and particularly relates to a ferrophosphorus bare battery cell recycling and processing method and system based on intelligent sorting, and the recycling and processing system comprises a feeding and crushing unit which is used for carrying out regular crushing on ferrophosphorus bare battery cells; the diaphragm sorting unit is used for separating a diaphragm from a pole piece material; the AI sorting unit is used for separating the positive plate and the negative plate based on visual identification; the positive plate processing unit is used for processing a positive plate and recycling aluminum foil and pole plate powder; the negative plate processing unit is used for processing a negative plate and recycling copper foil and graphite; the feeding and crushing unit, the diaphragm sorting unit and the AI sorting unit are sequentially connected, and the positive plate processing unit and the negative plate processing unit are respectively connected with the AI sorting unit.

Description

Technical Field

[0001] This invention belongs to the field of waste lithium-ion battery recycling technology, and specifically relates to a method and system for recycling bare phosphorus iron cells based on intelligent sorting. Background Technology

[0002] With the explosive growth of the global new energy industry (new energy vehicles, energy storage power stations), lithium iron phosphate batteries have captured over 60% of the power battery market due to their advantages such as low cost, high safety, and long cycle life. As of 2024, the cumulative amount of retired lithium iron phosphate batteries in my country exceeded 120 GWh, with an average annual growth rate of over 35%. Bare cells are defective products discarded during the manufacturing process of lithium batteries. As core components of batteries (including key materials such as positive electrode lithium iron phosphate, negative electrode graphite, aluminum / copper current collector, and separator), their recycling and disposal have become a core requirement for ensuring resource recycling and reducing environmental pollution.

[0003] The current bare cell recycling process has the following key technical pain points: (1) Traditional sorting efficiency is low and accuracy is poor: Existing technologies mostly rely on manual sorting (identifying positive and negative electrode sheets) or mechanical sorting (such as density sorting and air sorting). The efficiency of manual sorting is only 200-300 kg / day·person, and it is easily affected by visual fatigue, resulting in a mixing rate of more than 5%. Mechanical sorting has a small density difference between lithium iron phosphate positive electrode (density 2.5-3.0 g / cm³) and graphite negative electrode (density 2.2-2.4 g / cm³), and the sorting accuracy is less than 90%. The purity of the black powder is difficult to meet the regeneration requirements (purity > 95%). (2) Low material recovery rate and serious waste: Traditional processes often use incineration or direct disposal to treat the separator, which not only wastes PP / PE separator resources (the separator accounts for about 8-12% of the bare cell mass), but also generates VOCs pollution due to incineration; at the same time, during the stripping process of positive and negative electrode sheets, the electrode powder (positive electrode lithium iron phosphate, negative electrode graphite) is easily lost with dust, and the recovery rate is less than 85%. (3) High energy consumption and large pollution: The high temperature roasting method (traditional mainstream process) requires the cell to be processed at 500-800℃, with energy consumption reaching 800-1000kWh / ton, and a large amount of waste gas will be generated; the hydrometallurgical method requires the use of strong acids (sulfuric acid, hydrochloric acid) to dissolve metals, the subsequent wastewater treatment cost is high, and it is easy to cause the loss of lithium elements in the black powder (loss rate exceeds 10%). (4) Lack of process control and high environmental risks: Dust (including lithium iron phosphate and graphite particles) generated during crushing and sorting is not effectively collected, and the dust concentration in the workshop often exceeds 5mg / m³ (the national standard limit is 2mg / m³), posing occupational health risks; and there is no full-process exhaust gas treatment system, and direct emission of exhaust gas is likely to cause environmental complaints.

[0004] Therefore, the industry urgently needs a new process for recycling bare lithium iron phosphate cells to address the core pain points of traditional technologies and promote the industrialization and green development of waste lithium iron phosphate battery recycling. Summary of the Invention

[0005] This invention aims to solve at least one of the technical problems existing in related technologies. To this end, this invention proposes a method and system for recycling and processing bare phosphorus iron battery cells based on intelligent sorting. The recycling and processing method using this system has the characteristics of low energy consumption, high precision, high recycling rate, and environmental protection.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A phosphorus-iron bare battery cell recycling and processing system based on intelligent sorting includes a feeding and crushing unit for regularizing and crushing the phosphorus-iron bare battery cells; a separator sorting unit for separating separator and electrode materials; an AI sorting unit for separating positive and negative electrode sheets based on visual recognition; a positive electrode sheet processing unit for processing positive electrode sheets and recovering aluminum foil and electrode powder; and a negative electrode sheet processing unit for processing negative electrode sheets and recovering copper foil and graphite. The feeding and crushing unit, the separator sorting unit, and the AI ​​sorting unit are connected in sequence, and the positive electrode sheet processing unit and the negative electrode sheet processing unit are respectively connected to the AI ​​sorting unit.

[0007] In one embodiment, the feeding and crushing unit includes a feeding belt conveyor, a shear, and a crusher connected in sequence.

[0008] In one embodiment, the shearing machine is a biaxial shearing machine, the rotation speed of the shearing machine is 150-200 rpm, and the shearing gap of the shearing machine is 5-10 mm.

[0009] In one embodiment, the crusher is a single-shaft slicing crusher, the crusher rotates at a speed of 800-1000 rpm, and the slicing gap of the crusher is 0.5-1 mm.

[0010] In one embodiment, the diaphragm sorting unit includes a first-stage sorting unit and a second-stage sorting unit connected in sequence. Both the first-stage sorting unit and the second-stage sorting unit include a conveyor, a diaphragm sorter, and a vibrating screen connected in sequence.

[0011] In one embodiment, the conveyor is a negative pressure conveyor, and the air pressure of the conveyor is -500 to -800 Pa.

[0012] In one embodiment, the diaphragm sorter is used to sort out diaphragms. The diaphragm sorter sorts the diaphragms by airflow, and the airflow speed of the diaphragm sorter is 12–15 m / s.

[0013] In one embodiment, the vibrating screen is used to separate black powder, and the inclination angle of the vibrating screen is 20°-40°, the amplitude is 5-8mm, and the frequency is 20-50Hz.

[0014] In one embodiment, the AI ​​sorting unit includes a camera, an image processing module based on a CNN algorithm, and a pneumatic control system connected in sequence by electrical signals. The camera acquires images of the positive and negative electrode sheets obtained after sorting by the diaphragm sorting unit. The images acquired by the camera are input into the image processing module for processing to identify the positive and negative electrode sheets. The pneumatic control system sends the positive electrode sheets to the positive electrode sheet processing unit and the negative electrode sheets to the negative electrode sheet processing unit according to the identification results.

[0015] In one embodiment, the camera is a CCD camera with a shooting frame rate of 30fps.

[0016] In one embodiment, the pneumatic control system includes two pneumatic nozzles, the airflow pressure of which is 0.3–0.5 MPa and the response time of which is <0.1 s.

[0017] In one embodiment, the AI ​​sorting unit further includes a batch adaptive calibration module for adapting to battery cells from different manufacturers / batches. When replacing bare battery cells from different manufacturers / batches (with slight differences in color values), 100-200 sample images are automatically collected to update the algorithm parameters, eliminating the need for manual adjustments.

[0018] In one embodiment, the positive electrode processing unit includes a positive electrode conveyor, a positive electrode crusher, a positive electrode pneumatic stripper, and a positive electrode vibrating screen.

[0019] In one embodiment, the positive electrode conveyor includes at least one of a belt conveyor, a negative pressure conveyor, and a screw conveyor.

[0020] In one embodiment, the positive electrode sheet crusher is a single-shaft crusher, the rotation speed of the positive electrode sheet crusher is 1200–1500 rpm, and the crushing gap of the positive electrode sheet crusher is 1–2 mm.

[0021] In one embodiment, the wind speed of the positive electrode pneumatic stripper is 18–22 m / s, and the pressure of the stripping chamber of the positive electrode pneumatic stripper is -300 to -500 Pa.

[0022] In one embodiment, the screen mesh size of the positive electrode vibrating screen is 150 to 500 mesh.

[0023] In one embodiment, the negative electrode processing unit includes a negative electrode conveyor, a negative electrode crusher, a negative electrode pneumatic stripper, and a negative electrode vibrating screen.

[0024] In one embodiment, the negative electrode conveyor includes at least one of a belt conveyor, a negative pressure conveyor, and a screw conveyor.

[0025] In one embodiment, the negative electrode sheet crusher is a single-shaft crusher, and the rotational speed of the negative electrode sheet crusher is 800–1000 rpm.

[0026] In one embodiment, the wind speed of the negative electrode pneumatic stripper is 8–10 m / s.

[0027] In one embodiment, the mesh size of the negative electrode vibrating screen is 100 to 300 mesh.

[0028] In one embodiment, the system further includes an exhaust gas treatment unit for purifying dust and waste gas generated during the treatment process.

[0029] In one embodiment, the exhaust gas treatment unit includes a dust collector and an activated carbon adsorption tower.

[0030] In one embodiment, the filter area of ​​the bag filter is ≥50m², and the filter efficiency of the bag filter is ≥99.9%.

[0031] In one embodiment, the adsorption wind speed of the activated carbon adsorption tower is 0.8–1.2 m / s.

[0032] In one embodiment, a data monitoring unit is also included, which is used to monitor system operating parameters in real time and store data.

[0033] In one embodiment, the data monitoring unit includes an integrated PLC control system and online detection equipment, which can monitor material flow rate, purity, equipment operating status and environmental parameters in real time, and the data storage period is ≥1 year.

[0034] A method for recycling and processing bare phosphorus iron battery cells using the intelligent sorting-based phosphorus iron battery cell recycling and processing system described above includes the following steps: (1) The bare phosphorus iron battery cells are crushed by the feeding and crushing unit; (2) The material obtained from the crushing in step (1) is separated by a diaphragm sorting unit and the black powder is recovered; (3) The material processed in step (2) is identified and sorted by the AI ​​sorting unit to obtain positive electrode sheets and negative electrode sheets; (4) The positive electrode and the negative electrode are processed by the positive electrode processing unit and the negative electrode processing unit respectively to recover aluminum foil, copper foil, electrode powder and graphite.

[0035] In one embodiment, the particle size of the material obtained by crushing in step (1) is 5-10 mm.

[0036] In one embodiment, the AI ​​sorting step in step (3) uses a CNN algorithm for image recognition, with a recognition accuracy of ≥99%, a sorting precision of ≥98%, and a sorting efficiency of ≥1000 kg / hour.

[0037] The beneficial effects of this invention are: (1) Significant economic benefits: The material recovery rate is significantly improved, with the positive electrode powder recovery rate ≥92% (85% in traditional process), copper recovery rate ≥95% (90% in traditional process), and diaphragm recovery rate ≥92% (<60% in traditional process); energy consumption costs are significantly reduced. The mechanical and physical method consumes 300-400 kWh / ton, saving about RMB2-3 million in electricity costs per year compared to the traditional high-temperature roasting method (800-1000 kWh / ton) (calculated based on a processing capacity of 10,000 tons and an electricity cost of RMB0.6 / kWh).

[0038] (2) Outstanding environmental benefits: No high-temperature incineration throughout the process (no large amount of waste gas is generated) and no strong acid is used (avoiding wastewater pollution). The dust concentration in the exhaust gas is ≤8mg / m³ and VOCs is ≤20mg / m³, both of which are better than the national standards. Solid waste is significantly reduced, and membranes, black powder, etc. are all recycled. The solid waste emission is ≤5% (the solid waste emission of traditional processes is ≥15%).

[0039] (3) Strong industrial applicability: The entire process is automated, requiring only 2-3 people to monitor the equipment, reducing labor costs by more than 70% (traditional processes require 8-10 people); it can handle bare cells of different thicknesses and from different manufacturers without significantly adjusting process parameters, adapting to the diverse needs of the industry. Attached Figure Description

[0040] Figure 1 This is a process flow diagram of the phosphorus iron bare battery cell recycling and processing system based on intelligent sorting, according to an embodiment of the present invention. Detailed Implementation

[0041] The present invention will be further described below with reference to specific embodiments.

[0042] A recycling and processing system for bare phosphorus iron battery cells based on intelligent sorting, such as Figure 1 As shown, the system includes a feeding and crushing unit, a diaphragm sorting unit, an AI sorting unit, a positive electrode processing unit, a negative electrode processing unit, and a data monitoring unit. The feeding and crushing unit is used to standardize and crush the bare phosphorus-iron battery cells. The diaphragm sorting unit is used to separate the diaphragm and electrode materials. The AI ​​sorting unit is used to separate the positive electrode and negative electrode based on visual recognition. The positive electrode processing unit is used to process the positive electrode and recover aluminum foil and electrode powder. The negative electrode processing unit is used to process the negative electrode and recover copper foil and graphite. The exhaust gas treatment unit is used to purify the dust and exhaust gas generated during the process. The data monitoring unit is used to monitor the system operating parameters in real time and store the data. The feeding and crushing unit, the diaphragm sorting unit, and the AI ​​sorting unit are connected in sequence, and the positive electrode processing unit and the negative electrode processing unit are respectively connected to the AI ​​sorting unit.

[0043] The feeding and crushing unit includes a hydraulic feeding platform, a feeding belt conveyor, a shear, and a crusher connected in sequence; the shear is a twin-shaft shear with a rotation speed of 150-200 rpm and a shearing gap of 5-10 mm; the crusher is a single-shaft slicing crusher with a rotation speed of 800-1000 rpm and a slicing gap of 0.5-1 mm.

[0044] The diaphragm sorting unit includes two parallel diaphragm sorting lines, both of which are connected to the crusher in the feeding and crushing unit. Each diaphragm sorting line includes a first-stage sorting unit and a second-stage sorting unit connected in sequence. Both the first-stage and second-stage sorting units include a conveyor, a diaphragm sorter, and a vibrating screen connected in sequence. The second-stage sorting units of the two diaphragm sorting lines share a single vibrating screen. The conveyor is a negative pressure conveyor with an air pressure of -500 to -800 Pa. The diaphragm sorter is used to separate the diaphragms. The diaphragm sorter separates the diaphragms by airflow, with an air velocity of 12–15 m / s. The vibrating screen is used to separate the black powder. The inclination angle of the vibrating screen is 20°–40°, the amplitude is 5–8 mm, and the frequency is 20–50 Hz.

[0045] The AI ​​sorting unit is connected to the diaphragm sorting unit. The AI ​​sorting unit includes a camera, an image processing module based on a CNN algorithm, and a pneumatic control system connected in sequence by electrical signals. The camera captures images of the positive and negative electrode sheets after sorting by the diaphragm sorting unit. The images captured by the camera are input into the image processing module for processing to identify the positive and negative electrode sheets. The pneumatic control system sends the positive electrode sheets to the positive electrode sheet processing unit and the negative electrode sheets to the negative electrode sheet processing unit according to the identification results. The camera is a CCD camera with a shooting frame rate of 30fps. The pneumatic control system includes two pneumatic nozzles with an airflow pressure of 0.3–0.5MPa and a response time of <0.1s. The AI ​​sorting unit also includes a batch adaptive calibration module to adapt to cells from different manufacturers / batches. When replacing bare cells from different manufacturers / batches (with slight differences in color values), it automatically collects 100-200 sample images to update the algorithm parameters without manual adjustment.

[0046] The positive electrode processing unit is connected to the AI ​​sorting unit. The positive electrode processing unit includes, in sequence, a positive electrode belt conveyor, a positive electrode crusher, a negative pressure conveyor, a fully sealed box-type drum screen, a screw conveyor under the drum screen, a positive electrode pneumatic stripper, a screw conveyor, a positive electrode vibrating screen, a positive electrode black powder collection system, and a positive electrode black powder buffer bin. The positive electrode crusher is a single-shaft crusher with a rotational speed of 1200–1500 rpm and a crushing gap of 1–2 mm. The positive electrode pneumatic stripper has an air velocity of 18–22 m / s and a stripping chamber pressure of -300 to -500 Pa. The positive electrode vibrating screen is a rotary vibrating screen with a screen mesh size of 150 to 500 mesh.

[0047] The negative electrode processing unit is connected to the AI ​​sorting unit. The negative electrode processing unit includes, in sequence, a negative electrode belt conveyor, a negative electrode crusher, a negative pressure conveyor, a fully sealed box-type drum screen, a screw conveyor under the drum screen, a negative electrode pneumatic stripper, a screw conveyor, a negative electrode vibrating screen, a negative electrode black powder collection system, and a negative electrode black powder buffer bin. The negative electrode crusher is a single-shaft crusher with a rotation speed of 800–1000 rpm, and the pneumatic stripper has an air velocity of 8–10 m / s. The negative electrode vibrating screen is a rotary vibrating screen with a screen mesh size of 100 to 300 mesh.

[0048] The exhaust gas treatment unit includes a dust collector connected to the pneumatic stripping machine for positive and negative electrodes; it also includes an environmental dust removal system, which comprises a bag filter and an activated carbon adsorption tower. Dust is introduced into the bag filter through a negative pressure pipeline via a sealed hood for dust removal. The treated exhaust gas then enters the activated carbon adsorption tower for further adsorption. The bag filter has a filtration area ≥50m² and a filtration efficiency ≥99.9%. The adsorption velocity of the activated carbon adsorption tower is 0.8–1.2m / s.

[0049] The data monitoring unit includes an integrated PLC control system and online detection equipment, which can monitor material flow, purity, equipment operating status and environmental parameters in real time, with a data storage period of ≥1 year.

[0050] A method for recycling and processing bare phosphorus iron battery cells using the above-mentioned intelligent sorting-based phosphorus iron battery cell recycling and processing system includes the following steps: (1) The bare iron-phosphorus battery cells are crushed by the feeding and crushing unit to obtain materials with a particle size of 5-10 mm; (2) The material obtained from the crushing in step (1) is separated by a diaphragm sorting unit and the black powder is recovered; (3) The material processed in step (2) is identified and sorted by the AI ​​sorting unit to obtain positive electrode and negative electrode. In the AI ​​sorting step, the CNN algorithm is used for image recognition, with an identification accuracy of ≥99%, a sorting accuracy of ≥98%, and a sorting efficiency of ≥1000kg / hour. (4) The positive electrode and the negative electrode are processed by the positive electrode processing unit and the negative electrode processing unit respectively to recover aluminum foil, copper foil, electrode powder and graphite; (5) The dust and waste gas generated during the treatment process are purified and recycled through the exhaust gas treatment unit; (6) Data is recorded and processed in real time through the data monitoring unit.

[0051] Specifically, taking the processing of bare lithium iron phosphate cells (positive electrode: lithium iron phosphate; negative electrode: artificial graphite; aluminum foil thickness: 12μm; copper foil thickness: 8μm; separator: PP / PE composite membrane) as an example, the processing capacity is set at 1000 kg / hour, and the implementation steps are as follows: (1) Operation of the feeding and crushing unit Feeding: The bare battery cells are conveyed to the feeding belt via a hydraulic feeding platform. The belt speed is set to 0.8m / s, and the feeding rate is kept stable at 1000kg / hour. Dual-axis shearing: The battery cell enters a dual-axis shearing machine (180 rpm, shearing gap 8 mm) and is shredded into 30-40 mm fragments; Single-axis slicing: The fragments are conveyed to the single-axis slicer (900 rpm, 0.8 mm gap) by a negative pressure conveyor (air pressure -600 Pa, pipe diameter 150 mm). The slices are 6-8 mm regular crushed material with a crushing qualification rate ≥98% (fragment size deviation ≤±1 mm).

[0052] (2) Diaphragm sorting unit operation Primary airflow separation: The structured crushed material enters the first diaphragm separator (airflow velocity 14m / s, separation chamber pressure -700Pa), where coarse diaphragms are initially separated (output approximately 100kg / hour, containing approximately 6kg / hour of black powder); the coarse diaphragms then enter a vibrating screen (100-mesh screen, amplitude 6mm, frequency 30Hz), and after sieving, 5.8kg / hour of black powder is obtained (pass rate 96.7%), which is then sent to the black powder temporary storage silo; Secondary vibration separation: The remaining material (approximately 900 kg / hour, including positive electrode plates, negative electrode plates, and a small amount of residual diaphragm) enters the second diaphragm separator (vibrating screen inclination angle 30°, amplitude 7 mm, frequency 30 Hz), separating the residual diaphragm, broken positive electrode plate material, and broken negative electrode plate material.

[0053] (3) AI sorting unit operation System calibration: When processing the battery cell for the first time, 200 positive electrode and 200 negative electrode sample images were collected and input into the CNN algorithm module (trained based on the TensorFlow framework) to calibrate the Lab color value recognition threshold. The color difference values ​​of the positive and negative electrodes are shown in Table 1 below. Table 1.

[0054] CNN Network Structure (Based on TensorFlow Framework) This embodiment uses a classic feature extraction and classification structure of "multi-layer convolution + pooling + fully connected layers" for battery cell electrode color value recognition, as follows: Convolutional Layers: 3 convolutional layers in total, in the following order: Layer 1: 3×3 kernel size, 32 output channels, ReLU activation function; Layer 2: 3×3 kernel size, 64 output channels, ReLU activation function; Layer 3: 3×3 kernel size, 128 output channels, ReLU activation function. Pooling Layers: Corresponding to the 3 convolutional layers, each layer uses 2×2 max pooling to reduce dimensionality and retain key features. Fully Connected Layers: Contains 2 fully connected layers. Layer 1 has 256 nodes, and Layer 2 has 2 nodes (corresponding to positive and negative electrode classification). Finally, the classification probability is output through the Softmax function, providing a basis for color value threshold determination. Method for determining the universality threshold: To ensure that the threshold is universal for different battery cells, a strategy of "multi-batch sample training + feature distribution analysis + model adaptive optimization" is adopted. The steps are as follows: Multi-source sample coverage: Collect at least 10 battery cell samples from different manufacturers and batches, and collect 200 positive / negative electrode images for each batch to cover the natural fluctuations in Lab color values ​​caused by differences in materials and processes. Feature Learning and Distribution Analysis: Multiple batches of samples are input into the aforementioned CNN network to learn the color value differences between positive and negative electrodes; simultaneously, the intra-class variance (color value fluctuation within the same electrode) and inter-class distance (color value difference between positive and negative electrodes) of the L, a, and b channels are statistically analyzed. Dynamic Threshold Derivation: Based on the feature distribution output by the CNN model, combined with statistical methods (such as maximizing inter-class distance and minimizing intra-class variance), the model adaptively derives a Lab color value recognition threshold compatible with different batches. That is, the threshold is not a fixed value, but is dynamically optimized by the model based on the feature distribution of the input samples, ensuring accurate recognition even when new batches of cells are input. The Lab color value channel means: L-channel: Indicates brightness; the higher the value, the brighter the brightness. The L-value of the positive electrode is concentrated in the range of 25~28, while the L-value of the negative electrode is concentrated around 44, and the brightness difference between the two is significant.

[0055] Channel α: Represents the color change from green (negative) to red (positive). The α value of the positive electrode is negative (leaning towards green), and the α value of the negative electrode is positive (leaning towards red), showing a significant difference in color direction.

[0056] b channel: Represents the color change from blue (negative) to yellow (positive). The b value of the positive electrode is negative (leaning towards blue), and the b value of the negative electrode is positive (leaning towards yellow), showing a significant difference in color direction.

[0057] These data demonstrate the characteristic difference boundaries between positive and negative electrodes in the Lab color space. By learning the color value distribution of these samples, the CNN algorithm module can automatically calibrate the color value recognition threshold that can distinguish between positive and negative electrodes, ensuring universality for this batch and different batches of cells with similar processes (i.e., it can stably identify positive and negative electrodes from different sources).

[0058] Image acquisition: The mixture of positive and negative electrode sheets is conveyed to the sorting station via belt (speed 0.4m / s). A 5-megapixel CCD camera continuously takes pictures to acquire Lab color value images of each electrode sheet. The images are then input into a CNN algorithm module trained based on the TensorFlow framework. This module has been calibrated with the recognition threshold through multiple batches of samples (such as the color value data of positive and negative electrode sheets in Table 1 above). It can accurately determine whether each electrode sheet is a positive or negative electrode sheet based on the color value differences of the L (brightness), a (red-green direction), and b (yellow-blue direction) channels, with a recognition accuracy of 99.2%. Dynamic sorting: Based on the recognition results of the CNN algorithm, the system triggers the corresponding pneumatic sorting device. When a positive electrode sheet is identified, the No. 1 pneumatic nozzle (pressure 0.4MPa, response time 0.08s) is triggered to blow the material into the positive electrode channel; when a negative electrode sheet is identified, the No. 2 pneumatic nozzle (pressure 0.4MPa) is triggered to blow the material into the negative electrode channel. After sorting, the positive electrode sheet yield is 548kg / hour (purity 99.6%), the negative electrode sheet yield is 338kg / hour (purity 99.4%), the sorting accuracy is 99.5%, and the sorting efficiency is 1000kg / hour.

[0059] (4) Operation of the positive electrode processing unit High-speed crushing: The positive electrode sheet crushed material enters the single-shaft crusher (speed 1300rpm, crushing gap 1.5mm) and is crushed into 2-3mm particles; Airflow stripping: Particles enter the pneumatic stripper (wind speed 20m / s, stripping chamber pressure -400Pa), and the high-speed airflow impacts the electrode powder to detach it from the aluminum foil; Two-stage sieving: The mixture enters a two-stage vibrating screen (first stage 200 mesh screen, second stage 300 mesh screen, amplitude 5mm, frequency 28Hz) to separate aluminum foil and positive electrode powder; the aluminum content of the electrode powder is sampled and tested, and the result is 235ppm, which is then sent to the positive electrode black powder buffer.

[0060] (5) Operation of negative electrode processing unit Low-speed crushing: The anode sheet crushed material enters the crusher (900 rpm, crushing gap 2 mm) and is crushed into 3-4 mm particles; Pneumatic stripping: Particles enter a low-speed pneumatic stripper (wind speed 9m / s, stripping chamber pressure -350Pa) to gently strip graphite and copper foil; Linear sieving: The mixture enters a linear vibrating screen (150 mesh screen for the first stage, 200 mesh screen for the second stage, amplitude 8mm, frequency 25Hz), separating out approximately 27.2kg / hour of copper foil (99.3% purity) and approximately 310kg / hour of graphite; the graphite ash content is sampled and tested, and the result is 0.72% (meeting the external sales standard), and then sent to the negative electrode black powder buffer bin.

[0061] (6) Operation of exhaust gas treatment unit Dust collection: Each equipment's sealed hood introduces dust into a bag filter (PTFE filter bag material, 50㎡ filtration area, 1.2m / min) through a negative pressure pipeline (total air pressure -1100Pa, total pipe diameter 200mm), collecting approximately 8kg / hour of dust (mainly black dust), which is then sent to a black dust temporary storage bin; after bag filter dust collection, the dust concentration drops to 12mg / m³. Waste gas purification: The dust-removed waste gas (air volume 10000m³ / h, VOCs concentration 80mg / m³) enters the activated carbon adsorption tower (activated carbon filling amount 100kg, adsorption air velocity 1.0m / s), and the VOCs concentration is reduced to 18mg / m³. Emissions meet standards: The treated exhaust gas is discharged through a 15m high exhaust stack. Online monitoring shows that the dust concentration is 7.2mg / m³ and the VOCs concentration is 18mg / m³, both of which meet national standards.

[0062] (7) Data monitoring and recording Real-time monitoring: The PLC control system monitors the parameters of each piece of equipment in real time (such as crusher speed, separator wind speed, and exhaust gas concentration), and automatically alarms when abnormalities occur (such as alarming and suspending separation when the air pressure is lower than 0.3MPa). Data recording: Material output is recorded every 10 minutes, and energy consumption and exhaust gas data are recorded every 30 minutes. The data storage period is ≥1 year and can be queried and traced through the enterprise ERP system.

[0063] The recycling method of the present invention has the following characteristics: 1. Adaptive optimization technology for AI visual sorting: Breaking through the limitations of traditional fixed parameter sorting, it achieves accurate identification of positive and negative electrode sheets of bare cells from different manufacturers / batch through CNN algorithm + batch adaptive calibration (identification accuracy ≥99%). The sorting accuracy is improved by 8-10 percentage points compared with traditional mechanical sorting, and the sorting efficiency is improved by 3-5 times.

[0064] 2. Differentiated Separation Design for Positive and Negative Electrodes: To address the differences in bonding strength and material properties between the positive electrode (lithium iron phosphate-aluminum foil) and the negative electrode (graphite-copper foil), "high-speed airflow separation" (positive electrode, to avoid electrode powder residue) and "low-speed airflow separation" (negative electrode, to protect the graphite structure) are adopted respectively, achieving efficient separation of aluminum foil / copper foil from black powder. The aluminum content is controlled at ≤250ppm and the copper purity is ≥99.2%, both of which are superior to the existing levels in the industry (the industry average aluminum content is 500-800ppm and the copper purity is 97-98%).

[0065] 3. Two-stage diaphragm separation + black powder recovery system: The first two-stage diaphragm separation process of "airflow separation + vibrating screening" is used to improve the diaphragm recovery rate to over 92% (the traditional process diaphragm recovery rate is <60%). At the same time, it realizes efficient screening of black powder in the diaphragm (pass rate ≥95%), avoids black powder waste, and improves the total black powder recovery rate to over 92%.

[0066] 4. Full-process negative pressure closed-loop + multi-stage exhaust gas purification: The entire process from material feeding to exhaust gas emission is under negative pressure closed-loop (100% equipment sealing rate and 100% negative pressure pipeline coverage rate), and the dust concentration in the workshop is ≤2mg / m³ (meets occupational health standards); the combination process of "bag dust collection + activated carbon adsorption" achieves simultaneous purification of dust and VOCs, with an exhaust gas compliance rate of 100% and no secondary pollution.

[0067] 5. Modular + Data-Driven Management: Each unit (crushing, sorting, and recycling) adopts a modular design and can be flexibly combined according to production capacity (500-2000 kg / hour); it integrates an online detection and data traceability system to realize real-time monitoring of material status, equipment status, and environmental parameters, and product quality traceability, meeting the management and control needs of industrial production.

Claims

1. A smart sorting based phosphor-iron bare cell recycling system, characterized in that: Comprising a feeding and crushing unit for regularizing and crushing the phosphorus-iron bare battery cell; a separator sorting unit for separating the separator from the pole piece material; an AI sorting unit for separating the positive pole piece and the negative pole piece based on visual recognition; a positive pole piece processing unit for processing the positive pole piece and recovering the aluminum foil and the pole piece powder; a negative pole piece processing unit for processing the negative pole piece and recovering the copper foil and graphite; the feeding and crushing unit, the separator sorting unit and the AI sorting unit are connected in sequence, and the positive pole piece processing unit and the negative pole piece processing unit are connected with the AI sorting unit.

2. The phosphatic iron bare cell recycling system based on intelligent sorting according to claim 1, characterized in that: The feeding and crushing unit comprises a feeding belt conveyor, a shearing machine and a crusher connected in sequence.

3. The system for recycling phosphatic-iron bare cells based on intelligent sorting according to claim 1, characterized in that: The separator sorting unit comprises a first-stage sorting unit and a second-stage sorting unit connected in sequence, and the first-stage sorting unit and the second-stage sorting unit each comprise a conveyor, a separator sorting machine and a vibrating screen connected in sequence.

4. The system for recycling phosphatic-iron bare cells based on intelligent sorting according to claim 1, characterized in that: The AI sorting unit comprises a camera, an image processing module based on CNN algorithm and a pneumatic control system connected in sequence by electrical signals, the camera collects photos of the positive pole piece and the negative pole piece after sorting and processing by the separator sorting unit, the photos collected by the camera are input into the image processing module for processing, and the positive pole piece and the negative pole piece are identified, and the pneumatic control system sends the positive pole piece into the positive pole piece processing unit and the negative pole piece into the negative pole piece processing unit according to the identification result.

5. The smart sorting based phosphor-iron bare cell recycling system according to claim 1, characterized in that: The positive pole piece processing unit comprises a positive pole piece conveyor, a positive pole piece crusher, a positive pole piece pneumatic stripping machine and a positive pole piece vibrating screen.

6. The smart sorting based phosphor-iron bare cell recycling system according to claim 1, characterized in that: The negative pole piece processing unit comprises a negative pole piece conveyor, a negative pole piece crusher, a negative pole piece pneumatic stripping machine and a negative pole piece vibrating screen.

7. The smart sorting based phosphor-iron bare cell recycling system according to claim 1, characterized in that: It also comprises a tail gas treatment unit for purifying the dust and waste gas generated during the processing.

8. The smart sorting based phosphor-iron bare cell recycling system of claim 1, wherein: It also comprises a data monitoring unit for real-time monitoring of system operating parameters and data storage.

9. A method for recycling phosphor-iron bare battery cells using the smart sorting based phosphor-iron bare battery cell recycling system according to any one of claims 1-8, characterized in that: The method comprises the following steps: (1) crushing the phosphorus-iron bare battery cell by the feeding and crushing unit; (2) separating the separator and recovering the black powder by the separator sorting unit from the material crushed in step (1); (3) identifying and sorting the positive pole piece and the negative pole piece by the AI sorting unit from the material processed in step (2); (4) processing the positive pole piece and the negative pole piece by the positive pole piece processing unit and the negative pole piece processing unit respectively to recover the aluminum foil, the copper foil, the pole piece powder and the graphite.

10. A method as claimed in claim 9, characterised in that: The particle size of the material crushed in step (1) is 5-10 mm.

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