Lead-acid battery production process

Abstract

The invention discloses a lead-acid battery production process, and relates to the technical field of lead-acid battery production, and the lead-acid battery production process comprises the following steps: S1, lead powder preparation: carrying out grain cutting and closed Balton ball milling on an electrolytic lead ingot to obtain lead powder with BET0.65-0.75 m / g and apparent density 1.10-1.20 g / cm < 3 >, and the nitrogen-sealed oxygen content of a lead powder bin is less than or equal to 5vol%; s2, grid casting: heating the lead-calcium-tin-aluminum alloy to 480 + / -10 DEG C in a lead smelting furnace, and casting the lead-calcium-tin-aluminum alloy into a grid with the thickness tolerance of + / -0.05 mm through a continuous casting machine; s3, performing paste mixing; the device has the advantages that through side insertion of the inverted dovetail groove, isolation of the hydrophilic PET thin sheet and blocking of the top air curtain, condensate is guided to the collecting tank along the thin sheet and is pumped out in real time, no PbSO4 white ring is left on the surface of the polar plate, and the powder falling rate of the follow-up slicing and vibration procedures is remarkably reduced.

Description

Technical Field

[0001] This invention relates to the field of lead-acid battery production, and in particular to a lead-acid battery production process. Background Technology

[0002] In the curing process of lead-acid battery green plates, the industry has long used a high-temperature and high-humidity static curing method: the coated green plates are vertically inserted into a high-temperature resistant plastic tray, and the entire tray is pushed into a sealed curing chamber. The chamber temperature is maintained at approximately 50°C and the relative humidity at ≥95% by external steam and electric heating for 48 to 72 hours. This process aims to promote the full oxidation of free lead (Pb°) in the lead paste to PbO and form a tetrabasic lead sulfate (4BS) crystal network, thereby giving the plate the required mechanical strength and electrochemical activity.

[0003] However, two common and interconnected defects exist in actual production: 1. Surface "watermark" and powder shedding: Vapor on the top and side walls of the curing chamber condenses into droplets upon cooling. Due to the vertically close arrangement of the electrode plates, with a spacing of only 2–4 mm between adjacent plates, the condensate is drawn into the gaps between the plates by capillary action. After the moisture evaporates during the subsequent drying stage, a ring of white PbSO4 residue remains on the surface of the electrode plate, commonly known as a "watermark." The stress difference between the watermark area and the main body easily induces microcracks in the active material, leading to 1–2 wt% powder shedding during subsequent vibration, sheet separation, and assembly processes. This problem not only wastes lead materials but may also cause micro-short circuits inside the battery. 2. Insufficient oxidation of free lead in the core: The vertically packed structure creates a thermal resistance zone at the center of the electrode stack. External heat must be conducted to the core through the interface between the electrode and the air. The high humidity further inhibits local temperature increases, resulting in core temperatures generally falling below the set value. Under these low-temperature conditions, the oxidation rate constant of free lead decreases exponentially, causing the residual free lead at the end of curing to be lower than the target value. Excessive residual free lead not only weakens the initial capacity of the electrode but also increases heat release during the formation stage, posing a potential quality hazard. Summary of the Invention

[0004] The purpose of this invention is to solve the problems mentioned in the background art by proposing a lead-acid battery production process.

[0005] In view of the above problems, the present invention provides a lead-acid battery manufacturing process, comprising the following steps: S1. Lead powder preparation: Electrolytic lead ingots are granulated and ball-milled in a closed Barton mill to obtain lead powder with a BET of 0.65-0.75 m² / g and an apparent density of 1.10-1.20 g / cm³. The nitrogen-sealed oxygen content in the lead powder storage silo is ≤5 vol%. S2, Plate Grid Casting: The lead-calcium-tin-aluminum alloy is heated to 480±10℃ in a lead melting furnace and cast into a plate grid with a thickness tolerance of ±0.05mm by a continuous casting machine; S3, Paste Preparation: Add deionized water and sulfuric acid with a density of 1.40 g / cm³ to the lead powder. The ratio of lead powder to water to acid for the positive electrode is 100:10:8. For the negative electrode, add 0.3 wt% lignin, 0.2 wt% barium sulfate, and 0.15 wt% carbon black. The paste discharge temperature is ≤55℃. The apparent density is 3.90-4.10 g / cm³ for the positive electrode and 4.20-4.40 g / cm³ for the negative electrode. S4. Coating and Surface Drying: Apply lead paste to the grid and surface dry at 60℃ for 3 minutes, with a plate moisture content of 8-10 wt%. S5, Plate Curing: 5a Lateral stacking: Insert the green electrode plates laterally into the tray in an inverted dovetail groove at a 15° angle to the vertical, and insert 0.08-0.12mm hydrophilic PET sheets between adjacent electrode plates; 5b Core heat conduction: Insert 1mm aluminum foil-carbon fiber composite heat conduction partitions every 40-50mm in the electrode stack. The two ends of the partitions extend out of the curing chamber and contact the surface of the 50±2℃ constant temperature water plate, so that the core temperature of the stack rises to 48-52℃ within 6h and is maintained. 5c Top Air Curtain: Slit nozzles are arranged along the length of the top of the curing chamber to spray a compressed air curtain at 40-45℃ and 0.10-0.20m / s, forming a horizontal air cover of 5-10mm thickness; 5-day segmented humidity control: First maintain 50±2℃ and relative humidity ≥95%, then dry at 60℃ and relative humidity <30% for 8-12 hours, with free lead <1wt% and moisture <0.5wt%. S6. Separate and weigh the plates to obtain the cured electrode plates; S7. Battery Assembly: Employs a positive-to-negative structure, using an AGM separator to encase the positive electrode. Busbar casting temperature is 460±5℃. Heat-sealed tank cover. Helium mass spectrometry leak rate < ; S8, Battery formation: Injection of sulfuric acid with a density of 1.28 g / cm³, three-stage charging total capacity of 2.0-2.2 times the rated capacity; S9. Post-processing: Capacity, airtightness, and appearance inspection to obtain the finished lead-acid battery.

[0006] In the aforementioned lead-acid battery manufacturing process, the thermally conductive separator described in step 5b has a three-layer structure: a 1mm aluminum foil in the middle, and 0.2mm carbon fiber felt on each side, for a total thickness of 1.4mm. The aluminum foil and carbon fiber felt are bonded together with acid-resistant conductive adhesive, and the thermal conductivity is ≥200. Furthermore, the surface of the partition is coated with a 30-50µm acid-resistant silicone layer, with a thermal conductivity ≥1.2. .

[0007] In the aforementioned lead-acid battery manufacturing process, the acid-resistant conductive adhesive is composed of modified phenolic resin and silver-coated copper powder, with a volume resistivity of <0.01 Ω·cm and a 90-day acid-resistant weight loss of <0.5%. .

[0008] In the aforementioned lead-acid battery manufacturing process, the constant-temperature water plate in step 5b is a closed-loop circulating hot water system with a hot water temperature of 50±0.5℃ and a flow rate of 0.5-1. The contact area between the water plate and the heat-conducting partition is ≥200cm² / plate, and the contact pressure is 0.2-0.3MPa to ensure a thermal resistance <0.01. .

[0009] In the lead-acid battery production process described above, the slit nozzles in step 5c are 2-4 mm wide and symmetrically arranged on both sides of the top of the curing chamber. The nozzle outlet air velocity is 0.10-0.20 m / s. The compressed air is electrically heated to 40-45°C. A flow equalization plate is installed in front of the nozzles to ensure that the uniformity deviation of the air curtain thickness is <1 mm.

[0010] In the aforementioned lead-acid battery manufacturing process, the outer wall of the compressed air curtain's air supply duct in step 5c is covered with a 10mm thick aerogel insulation layer.

[0011] In the aforementioned lead-acid battery production process, the PET sheet surface described in step 5a is plasma-modified to achieve a water contact angle of <40°. The lower end of the sheet extends to the condensate collection tank at the bottom of the tray, and the sheet and the thermally conductive partition are arranged alternately to form a dual-channel structure for thermal and water conduction.

[0012] In the aforementioned lead-acid battery production process, during the initial 0-6 hours of the high humidity stage in step 5d, an additional 2.45GHz, 1.5-2.5kW microwave is applied. The microwave feed port is located on the side wall of the curing chamber, and the energy feeding time accounts for 20-25% of the total high humidity stage time. After the microwave is turned off, only hot air is running.

[0013] In the aforementioned lead-acid battery production process, step 5d employs an online NIR probe to monitor free lead and moisture on the electrode plates. The NIR probe has dual channels with wavelengths of 940nm and 1450nm, and a detection accuracy of ±0.1wt%. When free lead is <1wt% and moisture content is 7-9wt%, the process automatically switches to the drying stage, with a switching response time of <2min.

[0014] Compared with existing technologies, the technical solution provided in this application has at least the following technical effects or advantages: 1: This invention uses an inverted dovetail groove side insertion, hydrophilic PET sheet isolation, and top air curtain blocking to guide the condensate along the sheet to the collection tank and pump it out in real time. The surface of the electrode plate no longer has a white PbSO4 ring, and the powder loss rate in subsequent sheeting and vibration processes is significantly reduced, completely eliminating the watermark-microcrack-powder loss chain defect.

[0015] 2: This invention uses aluminum foil-carbon fiber thermally conductive separators to directly introduce constant temperature water into the stack center, supplemented by targeted microwaves. When NIR online determination shows free lead <1wt%, drying is switched on, allowing the core to rise to 48-52℃ within 6 hours and maintain it continuously. This significantly increases the free lead oxidation rate and shortens the curing cycle. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the architecture of a lead-acid battery manufacturing process according to an embodiment of the present invention. Detailed Implementation

[0017] The above technical solutions will now be described in detail with reference to the accompanying drawings and specific embodiments to provide a better understanding of them. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. It should be understood that the present invention is not limited to the exemplary embodiments used only to explain the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the drawings, not all of them.

[0018] Please see Figure 1 A lead-acid battery manufacturing process includes the following steps: S1. Lead Powder Preparation: Electrolytic lead ingots are first fed into a multi-blade rotary pelletizer. The blade spacing of the multi-blade rotary pelletizer is set to 2.00±0.05mm, which can cut the lead ingots into small lead pellets with a single weight of 0.20±0.01g and a particle weight difference coefficient Cv<2%. The pelletizing outlet is equipped with a high-speed camera and an AI edge recognition system to calculate the projected area of ​​each lead pellet in real time and convert it into mass. Once Cv>2%, the system fine-tunes the blade roller gap within 200ms to ensure that the subsequent lead pellets have consistent quality. The entire pelletizing process takes about 0.3s per pellet, forming a continuous and uniform flow of lead pellets. The lead pellets fall into a closed Barton ball mill by gravity. The drum speed is 28.0rpm, and oxygen oxidation is carried out inside. The oxygen flow rate is set to 15Nm. 3 / h, exhaust gas oxygen content is sampled every 60s to form a closed-loop control – when oxygen content <8 vol%, flow rate +0.5 Nm 3 / h, flow rate >12vol% -0.5Nm 3 The algorithm stabilizes the oxidation rate constant k at 0.90 ± 0.05 h / h.-1 To ensure consistent lead powder oxidation, the heat generated by the ball mill is carried away by a spiral cooling pipe and a variable frequency fan. The powder outlet temperature is controlled at 115±2℃. If the cooling water return temperature deviates from the set value by more than 1℃, the equipment will immediately alarm and shut down to prevent overheating. Simultaneously, the ground lead powder is temporarily stored in a powder silo. A laser TDLAS oxygen sensor on the silo top detects the oxygen content every second—if the oxygen content is >5 vol%, the nitrogen valve opening increases by 10%; if it is <3 vol%, the opening decreases by 5%. The steady-state oxygen content fluctuation is ±0.3 vol%, forming a slight positive pressure nitrogen protection to prevent secondary oxidation or spontaneous combustion of the lead powder. The final lead powder specification is: BET 0.70±0.02m. 2 / g, apparent density 1.15±0.02g / cm³ 3 .

[0019] S2. Plate Casting: The smelting process of lead-calcium-tin-aluminum alloy in the lead melting furnace employs precise control of temperature, liquid level, and composition. First, the alloy is heated to 480±10℃. An S-type thermocouple is inserted into the furnace chamber, and a solid-state relay (SSR) continuously samples the melt at a 1-second interval. The PID parameters are set to Kp=12, Ki=0.8, and Kd=3, limiting the temperature overshoot to within 0.5℃ to ensure the melt temperature remains stable within the target range. Simultaneously, a PE powder reducing agent is applied to the liquid surface, and a laser level gauge is used on the furnace top. The liquid level is read every 10 minutes. If the liquid level drops by more than 5 mm, the system automatically starts the feeding screw for 5 seconds, precisely adding 20 grams of PE powder to maintain the slag layer thickness between 10-15 mm and the lead content in the slag below 0.8 wt%, thereby maintaining the mirror-like stability of the alloy liquid surface and reducing oxidation loss. The melt then flows into the continuous casting machine, where the copper crystallizing wheel is pulled at a constant linear speed of 8.5 m / min. The cooling water flow rate inside the wheel is linked to the casting speed in real time, calculated using the formula Q_water = 1.2 × V_wheel + 2 (unit: ...). The system automatically adjusts the water volume to keep the temperature of the grid exit wheel below 80℃, preventing coarse grains. During the casting process, an online X-ray thickness gauge detects the grid thickness in real time at a frequency of 50 milliseconds and feeds the data back to the crystallizing wheel gap motor. Once the thickness deviation exceeds ±0.02 mm, the system immediately makes a fine adjustment, and the final finished grid thickness tolerance is locked within ±0.05 mm.

[0020] S3. Paste Preparation: Add deionized water and sulfuric acid with a density of 1.40 g / cm³ to the lead powder. The ratio of lead powder to water to acid for the positive electrode is 100:10:8. For the negative electrode, add an additional 0.3 wt% lignin, 0.2 wt% barium sulfate, and 0.15 wt% carbon black. The paste exit temperature should be ≤55℃. The apparent density is 3.90-4.10 g / cm³ for the positive electrode and 4.20-4.40 g / cm³ for the negative electrode. The process begins with a fixed material feeding ratio: During the water addition stage, a temperature braking algorithm is used. First, add 70% of the water. If the paste temperature rises >1℃ / min after 30 seconds, stop adding water and open the cooling jacket. If the rise is <0.5℃ / min, continue adding water. Throughout the process, ensure the temperature remains within a certain range. The temperature exceeds 55℃; concentrated acid is injected at a rate of 8kg / 100kg of lead powder in three stages: 0.8kg / min for 0-60 seconds, 1.5kg / min for 60-120 seconds, and 1.0kg / min after 120 seconds, to avoid local over-acidification; finally, the real-time torque second derivative "0 point" determination (the paste is immediately dispensed after a 10-second transition from positive to negative) is used to lock the apparent density of the positive electrode at 4.00±0.02g / cm³ and the negative electrode at 4.30±0.02g / cm³. If it deviates from ±0.02g / cm³, the amount of acid is automatically adjusted by 0.5kg. This ensures that the initial static formula is fully, accurately, and reproducibly implemented in every batch of lead paste.

[0021] S4. Coating and Surface Drying: Lead paste is coated onto the grid. Under the framework of "60℃, 3min, and 8-10wt% moisture content", a dual closed-loop system of laser thickness measurement and microwave moisture measurement is used on-site. During the coating process, the laser displacement sensor samples at a high speed of 2kHz. If the deviation is >±0.02mm, the servo motor is immediately directed to fine-tune the scraper gap (response <200ms) to ensure the thickness of the paste layer. Then, the electrode plate enters the 60℃ surface drying section, and the outlet infrared provides real-time feedback. If the temperature is >62℃, the PID automatically decrements by 1℃, and if it is <58℃, it increases by 1℃. At the same time, the online microwave moisture meter (RMSEP=0.1wt%) is calibrated every second, so that the hot air uniformly locks the surface moisture to the 8-10wt% required by the initial draft within a full 3 minutes, thus completing the seamless connection between dynamic control and static indicators.

[0022] S5. Electrode Curing: The green electrode is laterally inserted into the high-temperature resistant PP tray using an inverted dovetail groove at a 15° angle to the vertical. The dovetail groove has an opening of 60°, a depth of 12mm, and a surface Ra≤1.6µm to avoid scratching the electrode edge. A laser displacement sensor monitors the insertion depth in real time. If the deviation is >±0.5mm, the robot immediately performs a secondary correction with a repeatability of <0.2mm, providing a zero-error reference spacing for the subsequent alternating arrangement of thin sheets and separators. A 0.08-0.12mm hydrophilic PET sheet is inserted between adjacent electrodes, with a width equal to electrode width + 2mm and a length equal to electrode height + 5mm, the excess forming a liquid seal lip. The sheet is modified by 300W plasma (Ar / O2 = 9:1, 15s), reducing the contact angle from 78° to 34°, with an aging time ≥168h. The lower end of the sheet extends to a 1.5° inclined collection groove at the bottom of the tray, with 0.5mm × 2mm notches spaced 10mm apart, forming a micro-weir drip structure. This is alternated with 1.4mm aluminum foil-carbon fiber composite thermally conductive separators (spaced 40mm, each separator extending 3mm beyond the electrode on both sides). The separator surface is coated with a 30-50µm acid-resistant silicone layer (thermal conductivity ≥1.2). A 0.5mm air gap is left between the PET and the partition to achieve dual channels for heat conduction on one side and water conduction on the other side, without interference between them; The six-axis robot performs an insertion-photographing-AI recognition cycle at a rate of 3 seconds per sheet. The end-effector camera instantly detects wrinkles, gaps, or misalignments in the sheets; if an anomaly exceeds 1%, the robot automatically stops. A capacitive liquid level sensor at the bottom of the tray reads the condensate level every 30 seconds; if it exceeds 20mm, a diaphragm pump is activated to drain the condensate to the lead brick bed for processing; if it exceeds 5mm, the pump stops. The conductivity must be >500. The alarm prompts the replacement of the thin film, forming a five-loop system of insertion, detection, water conduction, heat conduction, and liquid drainage, ensuring that the electrode plate has a microscopic environment with watermark <0.3% and powder shedding <0.25% before entering the curing stage.

[0023] 5b core thermal conductivity: A 1 mm aluminum foil-carbon fiber composite thermally conductive separator is inserted every 40-50 mm, with a total thickness of 1.4 mm; the middle part is a 1 mm 1060 aluminum foil (thermal conductivity 237). ), 0.2 mm PAN-based carbon fiber felt on each side (thermal conductivity 50). An acid-resistant conductive adhesive (modified phenolic resin + silver-coated copper powder, volume resistivity <0.01Ω·cm, 90-day acid weight loss <0.5 mg / cm) is coated between the aluminum foil and the felt. -2 After roll curing, it forms an integrated metal-fiber core material with an in-plane thermal conductivity ≥200. The partition is then coated with a 30-50 µm layer of acid-resistant silicone (thermal conductivity ≥1.2). It is resistant to acid corrosion and ensures lateral thermal diffusion, with a surface roughness Ra≤1.0 µm and a contact thermal resistance with the electrode plate<0.002 K·cm² / W; The two ends of the partition extend out of the curing chamber and come into contact with the surface of the constant-temperature water plate at 50±0.5℃. The contact area is ≥200 cm² / plate, the contact pressure is 0.2-0.3 MPa (loaded by a disc spring), and the measured thermal resistance is <0.01 K / W. The water plate is a closed-loop hot water system with a flow rate of 0.5-1 The water pump uses frequency conversion and PID temperature control, with water temperature fluctuations within ±0.3 ℃; a platinum resistance thermometer (Pt100) is installed at the return water end, which feeds back to the PLC every 1 second. If the temperature drift is >0.1 ℃, the heating power is immediately corrected to ensure that the surface temperature of the partition plate is constant at 50±0.5℃. A T-type thermocouple is embedded in the geometric center of the stack. The data is uploaded to the PLC every 30 seconds: 0-2 h water plate set to 50℃ → 2-4 h gradually increased to 51℃ → 4-6 h increased to 52℃, with a heating slope ≤0.5℃ / 15 min to avoid thermal shock; after 6 h, it is maintained at 52±0.8℃ until curing is complete. This algorithm enables the electrode core to rise to 48-52℃ within 6 h and maintain it continuously, which shortens the heating time by 50% compared to traditional hot air heating, and the core-surface temperature difference is ≤2℃. The temperature difference ΔT between the inlet and outlet of the water plate is recorded every 10 seconds. If ΔT > 1.5 ℃ (increased thermal resistance indicates poor contact), the system automatically increases the contact pressure to 0.35 MPa and issues a maintenance prompt. If ΔT is still > 2 ℃, the robot removes the partition, automatically sprays thermal grease, and then inserts it again to ensure that the thermal resistance is always < 0.01 K / W. The water plate system is equipped with over-temperature protection: heating is immediately cut off and the cooling bypass is activated when the water temperature exceeds 55℃; the silicone layer on the baffle surface is subjected to 1000 hours, 60℃, and 1.28... Sulfuric acid immersion, weight loss <0.1%. .

[0024] 5c Top Air Curtain: Two rows of slit nozzles are arranged along the length of the top of the curing chamber. The nozzles are 2-4 mm wide and the length is the same as the curing chamber. They are symmetrically installed on both sides of the top and tilted downwards at 15° so that the compressed air sprayed out forms a horizontal air cover. The nozzle outlet wind speed is 0.10-0.20 m / s, and the wind speed deviation along the path is <0.02 m / s, forming a uniform air curtain with a thickness of 5-10 mm, covering the entire electrode plate surface, blocking the direct contact between the top steam and the cold wall surface, and reducing the dripping of condensate. Compressed air is first heated to 40-45℃ by an electric heater. The temperature is controlled by a PID closed loop with thermocouple feedback accuracy of ±0.5℃. A honeycomb flow equalization plate (6 mm aperture, 40% opening rate) is installed in front of the nozzle to ensure that the uniformity of the air curtain thickness is <1 mm, ensuring that the electrode surface is heated evenly and avoiding local overcooling or overheating. The entire outer wall of the compressed air supply duct is covered with a 10 mm thick aerogel insulation layer (thermal conductivity ≤ 0.02 W). The outer layer is covered with an aluminum foil reflective film, with an outer surface temperature of <35℃, which reduces heat loss and prevents condensation on the outer wall of the pipe due to temperature differences; the joints of the insulation layer are sealed with high-temperature resistant silicone to ensure that it will not fall off or absorb water during long-term operation. A hot-wire anemometer and a Pt100 temperature sensor are installed at the nozzle outlet, providing feedback to the PLC every 1 second. Wind speed <0.10 m / s → Variable frequency fan speed up +2 Hz; >0.20 m / s → Speed ​​down -2 Hz, locked at 0.15±0.02m / s; Temperature <40℃ → Electric heating power +5%; >45℃ → -5%, maintain at 42.5±0.5℃; The dual closed-loop system ensures that the air curtain thickness, temperature, and wind speed remain within the set range, with fluctuations within ±5%. A capacitive liquid level probe is arranged along the lower edge of the air cover. The thickness of the top condensate is detected every 10 seconds. If it is >1 mm, the top micro-pressure nozzle (0.3 MPa compressed air) is activated to purge for 5 seconds, blowing the condensate to the collection tanks on both sides to prevent droplets from falling onto the electrode plates. The liquid level signal is synchronously uploaded to the MES to form a "detection-purge-collection" closed loop, ensuring that the impact of top condensation is zero. The aerogel is then covered with a 0.5 mm stainless steel sheet to prevent mechanical impact; stainless steel clamps are installed every 2 m to fix the pipes, and silicone rubber is placed between the clamps and the insulation layer to buffer the cold bridge; after 5 years of system operation, the thermal conductivity of the insulation layer decreases by less than 5%, and no replacement is required, achieving a long-life, low-energy top thermal shield effect.

[0025] 5-day segmented humidity control: First, maintain a high humidity section of 50±2℃, relative humidity ≥95%, and duration of 20-28 hours to allow tetrabasic lead sulfate to fully nucleate and grow; then, run in a dry section of 60℃ and relative humidity <30% for 8-12 hours to quickly remove residual moisture and stabilize the crystal structure, ultimately achieving free lead on the electrode plates <1 wt% and moisture <0.5 wt%, fully meeting the initial draft specifications; during the first 0-6 hours of the high humidity section, apply an additional 2.45 GHz, 1.5-2.5 kW microwave: the feed port is a WR340 rectangular waveguide symmetrically arranged on the side wall of the curing chamber, with a duty cycle of 20-25% (3 min on, 2 min off), only in the initial stage to take advantage of the high dielectric loss of the water-containing paste to preferentially increase the core temperature; after 6 hours, turn off the microwave and rely solely on hot air to complete the remaining curing, which is both energy-saving and avoids excessive surface drying; The fully online NIR probe (940 nm / 1450 nm dual-channel, detection accuracy ±0.1 wt%) scans every 10 seconds to invert free lead and moisture content in real time. When free lead <1 wt% and moisture 7-9 wt% are detected for 10 consecutive times, the PLC automatically switches to the drying stage within <2 minutes, with a heating rate ≤1 ℃ / min to prevent electrode cracking. Microwave power is linked to the NIR signal: if moisture <6 wt% and microwave is still running, the system automatically reduces power to 1.0 kW; if moisture <5 wt%, microwave is immediately cut off to avoid overheating; the sidewall microwave leakage meter monitors in real time, and stops immediately if >1 mW / cm² to ensure operational safety. During the drying stage, 60℃, RH<30% slightly positive pressure hot air (0.2 kPa) is used. The top return air and bottom supply air form a longitudinal vortex, with a dehydration rate of 0.8% / min. The online microwave moisture meter at the outlet is calibrated every 30 seconds, and the machine automatically stops when the moisture content is ≤0.5 wt%. Throughout the process, temperature, humidity, microwave power, and NIR signal are uploaded to the MES every 1 second to form big data on monopolar plate curing.

[0026] S6. Segmentation and weighing yields cured electrode plates. On-site, a vacuum suction cup and weighing sensor integrated unit is used. Each 0.1 g resolution weighing sensor is integrated at the end of the suction cup. If the mass deviation of a single electrode plate is >±1 g, it is automatically diverted to the rework channel by a pneumatic lever. The Cv of the entire batch is <0.5%. The robot cycle is 3 seconds per piece, the vacuum degree is kept constant at -60 kPa, and the weighing signal is uploaded to MES every 100 ms to form a single electrode plate quality identification. This provides a mass symmetry basis for subsequent positive and negative packing and generates batch big data at the same time, which is used by AI to predict the capacity difference of the packing and remove potential outlier electrode plates in advance.

[0027] S7. Battery Assembly: Employs a positive-to-negative structure, using an AGM separator to encase the positive electrode. Busbar casting temperature is 460±5℃. Heat-sealed tank cover. Helium mass spectrometry leak rate < ; S8, Battery formation: Injection of sulfuric acid with a density of 1.28 g / cm³, three-stage charging total capacity of 2.0-2.2 times the rated capacity; S9. Post-processing: Capacity, airtightness, and appearance inspection to obtain the finished lead-acid battery.

[0028] This detailed embodiment elaborates on the internal operating logic of each major functional module, aiming to provide a detailed basis and explanation for those skilled in the art to understand and implement it. It should be emphasized that the above description constitutes a specific, preferred embodiment, but the concept of the present invention is not limited thereto. Any equivalent transformations, modifications, or improvements based on the core spirit of the present invention, without departing from the technical principles and scope disclosed in this specification, should be considered to fall within the scope of protection claimed by the present invention, as long as they achieve the same or similar technical effects.

Claims

1. A lead-acid battery manufacturing process, characterized in that, Includes the following steps: S1. Lead powder preparation: Electrolytic lead ingots are granulated and ball-milled in a closed Barton mill to obtain lead powder with a BET of 0.65-0.75 m² / g and an apparent density of 1.10-1.20 g / cm³. The nitrogen-sealed oxygen content in the lead powder storage silo is ≤5 vol%. S2, Plate Grid Casting: The lead-calcium-tin-aluminum alloy is heated to 480±10℃ in a lead melting furnace and cast into a plate grid with a thickness tolerance of ±0.05mm by a continuous casting machine; S3, Paste Preparation: Add deionized water and sulfuric acid with a density of 1.40 g / cm³ to the lead powder. The ratio of lead powder to water to acid for the positive electrode is 100:10:

8. For the negative electrode, add 0.3 wt% lignin, 0.2 wt% barium sulfate, and 0.15 wt% carbon black. The paste discharge temperature is ≤55℃. The apparent density is 3.90-4.10 g / cm³ for the positive electrode and 4.20-4.40 g / cm³ for the negative electrode. S4. Coating and Surface Drying: Apply lead paste to the grid and surface dry at 60℃ for 3 minutes, with a plate moisture content of 8-10 wt%. S5, Plate Curing: 5a Lateral stacking: Insert the green electrode plates laterally into the tray in an inverted dovetail groove at a 15° angle to the vertical, and insert 0.08-0.12mm hydrophilic PET sheets between adjacent electrode plates; 5b Core heat conduction: Insert 1mm aluminum foil-carbon fiber composite heat conduction partitions every 40-50mm in the electrode stack. The two ends of the partitions extend out of the curing chamber and contact the surface of the 50±2℃ constant temperature water plate, so that the core temperature of the stack rises to 48-52℃ within 6h and is maintained. 5c Top Air Curtain: Slit nozzles are arranged along the length of the top of the curing chamber to spray a compressed air curtain at 40-45℃ and 0.10-0.20m / s, forming a horizontal air cover of 5-10mm thickness; 5-day segmented humidity control: First maintain 50±2℃ and relative humidity ≥95%, then dry at 60℃ and relative humidity <30% for 8-12 hours, with free lead <1wt% and moisture <0.5wt%. S6. Separate and weigh the plates to obtain the cured electrode plates; S7. Battery Assembly: Employs a positive-to-negative structure, using an AGM separator to encase the positive electrode. Busbar casting temperature is 460±5℃. Heat-sealed tank cover. Helium mass spectrometry leak rate < ; S8, Battery formation: Injection of sulfuric acid with a density of 1.28 g / cm³, three-stage charging total capacity of 2.0-2.2 times the rated capacity; S9. Post-processing: Capacity, airtightness, and appearance inspection to obtain the finished lead-acid battery.

2. The lead-acid battery manufacturing process according to claim 1, characterized in that, The thermally conductive partition described in step 5b has a three-layer structure: a 1mm aluminum foil in the middle, and 0.2mm carbon fiber felt on each side, with a total thickness of 1.4mm. The aluminum foil and carbon fiber felt are bonded together with acid-resistant conductive adhesive, and the thermal conductivity is ≥200. Furthermore, the surface of the partition is coated with a 30-50µm acid-resistant silicone layer, with a thermal conductivity ≥1.

2. .

3. The lead-acid battery manufacturing process according to claim 2, characterized in that, The acid-resistant conductive adhesive is composed of modified phenolic resin and silver-coated copper powder, with a volume resistivity of <0.01 Ω·cm and a 90-day acid-resistant weight loss of <0.5%. .

4. The lead-acid battery manufacturing process according to claim 1, characterized in that, The constant temperature water plate mentioned in step 5b is a closed-loop hot water system with a hot water temperature of 50±0.5℃ and a flow rate of 0.5-1. The contact area between the water plate and the heat-conducting partition is ≥200cm² / plate, and the contact pressure is 0.2-0.3MPa to ensure a thermal resistance <0.

01. .

5. The lead-acid battery manufacturing process according to claim 1, characterized in that, The slit nozzles described in step 5c are 2-4 mm wide and symmetrically arranged on both sides of the top of the curing chamber. The nozzle outlet air velocity is 0.10-0.20 m / s. The compressed air is electrically heated to 40-45℃. A flow equalization plate is installed in front of the nozzles to ensure that the uniformity deviation of the air curtain thickness is <1 mm.

6. The lead-acid battery manufacturing process according to claim 1, characterized in that, The outer wall of the compressed air curtain's air supply duct in step 5c is covered with a 10mm thick aerogel insulation layer.

7. The lead-acid battery manufacturing process according to claim 1, characterized in that, In step 5a, the surface of the PET sheet is modified by plasma hydrophilicity, with a water contact angle of <40°. The lower end of the sheet extends to the condensate collection tank at the bottom of the tray, and the sheet and the heat-conducting partition are arranged alternately to form a heat-conducting and water-conducting dual-channel structure.

8. The lead-acid battery manufacturing process according to claim 1, characterized in that, During the first 0-6 hours of the high humidity stage in step 5d, an additional 2.45GHz, 1.5-2.5kW microwave is applied. The microwave feed port is located on the side wall of the curing chamber, and the energy feeding time accounts for 20-25% of the total time of the high humidity stage. After the microwave is turned off, only the hot air runs.

9. A lead-acid battery manufacturing process according to claim 1, characterized in that, In step 5d, an online NIR probe is used to monitor the free lead and moisture on the electrode plate. The NIR probe has dual channels with wavelengths of 940nm and 1450nm and a detection accuracy of ±0.1wt%. When the free lead is <1wt% and the moisture content is 7-9wt%, it automatically switches to the drying stage with a switching response time of <2min.

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