An automated system and method for preparing zinc-silver battery positive electrode plates

Abstract

This invention discloses an automated system and method for preparing zinc-silver battery positive electrode plates, belonging to the technical field of battery manufacturing equipment. Addressing the challenges in zinc-silver battery positive electrode plate preparation, such as powder stratification and agglomeration, plate fragility, long sintering cooling time, and low detection accuracy, this invention proposes the following innovations: Powder weighing utilizes a combined rotary screw and belt feeding system, achieving non-extrusion and flipping conveying and low-drop-height flat laying, avoiding cold welding of silver powder and silver-carbon stratification; preheating the mold before pressing improves density uniformity; sintering employs a double-layer circulating tunnel furnace with an air-cooled outlet unit, shortening cooling time; the robotic arm end uses a flexible suction cup and S-curve acceleration / deceleration control to achieve damage-free transfer of fragile plates; and integrated detection includes weighing, five-point coaxial thickness measurement, and deep learning appearance recognition, significantly improving detection accuracy. This invention achieves full-process automation, increasing production efficiency, reducing labor costs, lowering scrap rates, and significantly improving product consistency and reliability.

Description

Technical Field

[0001] This invention belongs to the field of battery manufacturing equipment technology, specifically relating to an automatic preparation system and method for zinc-silver battery positive electrode plates, which is suitable for the automated production of high-reliability zinc-silver battery positive electrode plates in aerospace, military and other industries. Background Technology

[0002] Zinc-silver batteries are widely used in high-end fields such as aerospace and military equipment due to their high specific energy and stable discharge voltage. Currently, the preparation of zinc-silver battery positive electrode plates mostly employs manual or semi-mechanized operations. A typical process flow is: manually weighing the positive electrode powder and metal skeleton → pouring the powder into a mold and manually leveling it → pressing and shaping → manually removing the electrode plate and weighing it → high-temperature sintering → manual inspection of appearance, thickness, and weight. This existing technology suffers from the following six technical problems, which collectively result in low automation levels, poor product consistency and reliability in the zinc-silver battery positive electrode plate preparation process, failing to meet the high reliability and rapid response requirements of modern special equipment.

[0003] Problem 1: The overall level of automation in the process is low, with many manual operation steps (about 10 steps), resulting in high labor intensity for workers and limited production efficiency.

[0004] Question 2: Difficulty in automatically weighing powder. The positive electrode powder consists of silver powder (density 10.5 g / cm³). 3 ) and charcoal powder (density 2.0 g / cm³) 3 This mixture exhibits significant density differences. In conventional automated weighing methods, vibration feeding exacerbates powder stratification (such as...). Figure 8 As shown), the screw feeding causes the silver powder to agglomerate during cold soldering (e.g. Figure 7 As shown in the figure, none of them can meet the process requirements. Those skilled in the art have attempted to directly integrate conventional vibrating feeders and screw feeders into automated production lines, but all have failed due to delamination or agglomeration.

[0005] Problem 3: The pressing and molding process is isolated and lacks coordination with the preceding and following processes. Manual loading and unloading pose safety hazards, and parameter management is outdated.

[0006] Question 4: The sintering process has a low degree of automation, and manual loading and unloading poses a risk of high temperatures; after sintering, it needs to be naturally cooled to room temperature before it can be tested, which takes about 60 minutes, seriously affecting the production rhythm.

[0007] Question 5: The positive electrode plate is thin, has a loose structure, and low mechanical strength, making it a fragile component (e.g., Figure 10 (As shown). During manual handling, the plates are easily damaged due to stress concentration or oil contamination, with a breakage rate of about 2%. The rigid suction cups or grippers of conventional robotic arms can also crush the plates.

[0008] Question 6: Post-sintering inspections are scattered, with weight, thickness, and appearance inspections being independent of each other, requiring multiple manual handling and positioning; appearance inspection relies on manual visual inspection, which is highly subjective, has a high rate of missed inspections, and the accuracy rate of pass / fail judgment is only about 95%. Summary of the Invention

[0009] This invention aims to solve the above-mentioned problems and provides a fully automated preparation system and method covering the entire process from powder weighing to finished product sorting, so as to realize the replacement of manual operation with machines and improve production efficiency, product consistency and reliability.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: an automatic preparation system for a zinc-silver battery positive electrode plate, wherein the positive electrode plate is formed by pressing a mixture of silver powder and carbon powder and has a loose and fragile structure; the system includes: An automatic powder weighing device includes a rotary screw feeding mechanism and a belt powder feeding mechanism. The rotary screw feeding mechanism uses the rotation of the cylinder to cause the inner spiral blades to pick up the powder and then let it fall naturally, achieving non-compression and tumbling conveying. The belt powder feeding mechanism uses a non-adhesive flat belt and is used in conjunction with a translation module to achieve low drop height and uniform flat drop. The pressing equipment includes a press and a heating element set in the mold placement table for preheating the mold to 40°C~60°C; The tunnel sintering equipment includes a positive electrode plate conveying device with upper and lower double-layer circulation, a sintering furnace, and an air-cooled unit located above the positive electrode plate discharge port, wherein the air-cooled unit has adjustable wind speed and wind temperature. The automatic inspection equipment includes a weighing mechanism, a thickness measuring mechanism that uses a coaxial displacement sensor to achieve five-point automatic thickness measurement, and a visual inspection mechanism that uses an industrial camera combined with a deep learning algorithm to identify plate defects. Multiple handling robotic arms, each equipped with a flexible suction cup and a vision positioning module at its end, and the motion control of the handling robotic arms adopts S-curve acceleration and deceleration to achieve flexible contact with the electrode plate and smooth transfer.

[0011] Preferably, as an improvement, the automatic powder weighing device is further equipped with a capacitive humidity sensor and a dry nitrogen purging device, which are used to monitor the moisture content of the powder in real time and automatically purge when the moisture content exceeds the standard.

[0012] Preferably, as an improvement, the flat belt in the belt conveyor is made of TPU material.

[0013] Preferably, as an improvement, the press is a servo hydraulic press, equipped with a pressure sensor and a closed-loop control system, and connected to the central control system via an industrial Ethernet.

[0014] Preferably, as an improvement, in the tunnel sintering equipment, high-temperature heating tubes and thermocouples are evenly distributed at the top of the sintering furnace cavity; the upper and lower double-layer circulating positive electrode plate conveying device includes an upper transmission device and a lower transmission device. The positive electrode plate is fed into the sintering furnace through the upper layer, and after sintering, it is sent to the discharge port through the upper layer. The empty pallet returns to the feeding end through the lower layer.

[0015] Preferably, as an improvement, the defects identified by the visual inspection mechanism include cracks, missing edges, deformation, and uneven color.

[0016] Secondly, the present invention provides an automated method for preparing a zinc-silver battery positive electrode plate, wherein the following steps are performed using the system described in any of the above-mentioned methods: Powder weighing steps: The mixture of silver powder and carbon powder is fed into the rotary screw feeding mechanism, and conveyed to the belt powder feeding mechanism through non-extrusion flipping. Then, the belt is driven by the translation module to achieve low drop height and flat drop of the material onto the material tray, and the weighing mechanism weighs it in real time. Pressing steps: The weighed powder and skeleton are put into a mold preheated to 40℃~60℃, spread out, and then transferred to a press to press and shape. After demolding, the positive electrode plate is obtained. Sintering steps: Place the positive electrode plate on the upper layer of the double-layer circulating positive electrode plate conveying device and send it into the sintering furnace for sintering. After sintering, send it to the discharge port through the upper layer and start the air-cooling unit for forced cooling at the same time. Inspection and sorting steps: The sintered positive electrode plates are sequentially sent to the weighing mechanism, visual inspection mechanism and thickness measurement mechanism for weight, appearance and thickness inspection, and automatically sorted according to the inspection results; In all the above transfer processes, the handling robotic arm uses a flexible suction cup to pick up the electrode plate and uses an S-shaped curve acceleration and deceleration to control the motion trajectory.

[0017] Preferably, as an improvement, in the powder weighing step, when the capacitive humidity sensor detects that the moisture content of the powder exceeds the standard, the drying nitrogen purging device is automatically started to dehumidify.

[0018] Preferably, as an improvement, the thickness measurement step uses a coaxial displacement sensor to automatically measure the thickness at five measurement points on the surface of the positive electrode plate.

[0019] The working principle of this invention is: 1. To address the issue of low overall automation levels, system integration and multi-stage collaboration are key solutions. This invention utilizes multiple robotic arms in conjunction with conveyor components to connect weighing, pressing, sintering, and testing processes into a continuous production line. A host computer centrally stores process parameters, which can be retrieved with a single click by model number, enabling automatic connection between processes. The original process reduces 10 manual operation points to only two: manual sheet spreading and finished product unloading, reducing manual operations by 80%. The single-piece production cycle is shortened to 20 minutes, production efficiency is increased by 33.3%, and labor costs are reduced by 50%.

[0020] 2. To address the issue of powder stratification and agglomeration during weighing, a combined rotary drum and belt feeding system is used to solve the problem. Technical challenges: Silver powder has a much higher density than carbon powder, and it is also soft and easily cold-welded. Conventional vibratory feeding causes the denser silver powder to sink to the bottom and the carbon powder to float, resulting in stratification; conventional screw feeding exerts strong compression on the powder, causing the silver powder particles to undergo plastic deformation and cold-weld together into silver ingots. Those skilled in the art generally believe that screw conveying inevitably involves compression, and that vibratory feeding is suitable for most powders; therefore, a technical bias has long existed in the automated weighing of zinc-silver battery cathode powder.

[0021] This invention innovatively introduces a rotary screw feeder mechanism, employing a rotating cylinder and inner spiral blades to scoop up and naturally drop powder, achieving non-compression and tumbling conveying. The material is scooped up and dropped once with each rotation within the cylinder, not only avoiding compression and densification but also disrupting the tendency for stratification caused by density differences through continuous tumbling and mixing. The belt conveyor uses a non-adhesive TPU flat belt, achieving low-drop-height, flat-laying material drop through a translation module, avoiding secondary stratification caused by high-drop impacts.

[0022] Weighing accuracy has been improved from ±0.1g to ±0.05g, ensuring uniform powder mixing without stratification or clumping. Furthermore, an observable hopper is installed before the rotary screw feed mechanism. A capacitive humidity sensor and a drying nitrogen purging device added to the hopper allow for real-time control of the powder's moisture content, preventing humidity changes from affecting flowability and weighing accuracy.

[0023] 3. To address the issues of isolated pressing processes and outdated parameter management, a combination of mold preheating and servo closed-loop control is used to solve the problem. This invention incorporates heating elements within the mold placement platform to preheat the mold to 40℃~60℃. The heat conduction principle ensures the powder is in a suitable thermodynamic state from the initial stage of mold entry, avoiding edge densification differences caused by cold mold walls, thereby improving density distribution uniformity and reducing edge crack defects on the electrode plates. Simultaneously, the press employs a servo hydraulic press equipped with a pressure sensor and a closed-loop control system, connected to the central control system via industrial Ethernet, achieving a pressure control accuracy of ±1%FS (an 80% improvement over the existing ±5%FS). All pressing parameters are stored in the host computer according to product model and automatically sent upon recall, eliminating errors and waiting time associated with manual repetitive settings.

[0024] 4. The upper and lower double-layer circulating tunnel furnace combined with the air-cooled unit solves the problems of insufficient sintering automation and low cooling efficiency. Technical Challenges: After sintering, the electrode plates must be cooled to room temperature before testing; otherwise, high temperatures will affect weighing accuracy and damage the thickness sensor. Traditional processes use natural cooling, which takes approximately 60 minutes, becoming a bottleneck in the overall production line. Those skilled in the art generally believe that forced cooling may introduce thermal stress, leading to electrode plate cracking; therefore, natural cooling has been the long-standing practice.

[0025] This invention designs a double-layer circulating positive electrode plate conveying device: the upper transmission device feeds the positive electrode plates into the sintering furnace, and after sintering, they are conveyed to the positive electrode plate discharge port via the upper layer; the empty tray returns to the feeding end via the lower transmission device, forming a fully automated reflux process. The sintering furnace automatically docks with the robotic arm to realize automatic plate stacking and feeding / discharging, eliminating the risks of high-temperature operation. An air-cooled unit is installed directly above the discharge port, which provides forced cooling through programmable control of air speed (5~15m / s) and air temperature (10℃~30℃). Experiments have verified that the plate temperature can be rapidly reduced from 500℃ to room temperature without introducing thermal stress cracks.

[0026] Beneficial effects: Cooling time is reduced from 60 minutes for natural cooling to 10 minutes, cooling efficiency is increased by 83.3%, production cycle is significantly accelerated, and the risk of manual high-temperature operation is eliminated.

[0027] 5. Flexible suction cups and S-curve motion control solve the problem of breakage during transport of fragile electrode plates. Technical Challenges: Before sintering, the positive electrode plates of zinc-silver batteries are in a green state with extremely low strength. The impact force generated by the rigid suction cups or grippers of conventional industrial robots upon contact can cause the edges of the plates to crack. Even with reduced suction cup pressure, the rough and porous surface of the plates leads to severe air leakage, making stable suction impossible. Existing technologies lack automated handling solutions for such loose and fragile plate-like components.

[0028] The robotic arm of this invention integrates a flexible suction cup (Shore A hardness 30-50) and a vision positioning module at its end. The vision system accurately identifies the position and height of the electrode plate, guiding the suction cup to align. The flexible suction cup is made of elastic material, which can adapt to the microscopic undulations of the electrode plate surface upon contact, reducing contact pressure. The robotic arm movement adopts S-curve acceleration and deceleration control, ensuring that the speed of the suction cup in contact with the electrode plate is ≤5mm / s, the contact force is ≤1.0N, and the start and stop are smooth and vibration-free.

[0029] The damage rate during transport has been reduced from 2% to 0% with manual handling, and sweat contamination has been eliminated, achieving fully automated and non-destructive transport from demolding and sintering to testing.

[0030] 6. The integrated automatic detection and sorting system solves the problems of scattered detection and low accuracy. This invention integrates weight, thickness, and appearance inspection into a single production line. The weighing mechanism uses a high-precision weighing module with an accuracy of ±0.05g (a 50% improvement); the thickness measuring mechanism uses a coaxial displacement sensor to automatically measure thickness at five measurement points on the electrode surface, with an accuracy of ±0.005mm (a 90% improvement); the visual inspection mechanism uses an industrial camera combined with deep learning algorithms to train recognition models for four types of defects: cracks, missing edges, deformation, and uneven color, improving the accuracy rate from 95% to 99% based on manual visual inspection. The inspection results are then automatically sorted to the corresponding sorting boxes by a robotic arm.

[0031] Overall beneficial effects: Through the above six technological innovations, this invention systematically solves the overall technical problems of low automation and poor product consistency in existing zinc-silver battery cathode plate manufacturing processes. The comprehensive benefits are as follows: Technical aspects: It facilitates precise control of parameters in each process, significantly improving product consistency and reliability; manual operation steps are reduced by 80%, and the production cycle of a single piece is shortened by 33.3%.

[0032] Economic benefits: Production capacity increased by 50%, labor costs decreased by 50%, the overall scrap rate dropped from 7% to below 1%, and scrap losses decreased by more than 85%.

[0033] At the societal level: ensuring the demand for highly reliable batteries for key model projects; freeing workers from high-dust and high-temperature environments; and promoting technological progress and green manufacturing in the industry.

[0034] The difference between this invention and conventional equipment combinations: Those skilled in the art would readily assume that weighing equipment, presses, sintering furnaces, and testing equipment can be connected in series via a robotic arm. However, the preparation of zinc-silver battery positive electrode plates presents the following unique technical challenges, making it impossible to directly combine conventional equipment: The powder properties are contradictory: the density of silver powder and carbon powder differs by 5 times, and silver powder is soft. Conventional feeding methods (vibration, screw) will disrupt the uniformity of mixing, leading to the failure of automated weighing.

[0035] The mechanical properties of the electrode plates are contradictory: the green electrode plates before sintering have extremely low strength, and conventional gripping methods (rigid grippers, ordinary suction cups) will cause them to break. There is a lack of effective solutions in the existing technology.

[0036] The thermal process cycle is contradictory: after sintering, the material must be cooled to room temperature before it can be tested. Natural cooling takes too long, but forced cooling may introduce thermal stress cracks, which is a technical bias.

[0037] This invention addresses each of the aforementioned contradictions by proposing solutions with different underlying principles: (1) a rotating screw drum replacing the screw / vibration – achieving non-extrusion and flipping conveying; (2) a flexible suction cup + S-curve replacing rigid gripping – achieving non-destructive and gentle handling; and (3) air cooling + reflow oven replacing natural cooling – achieving active and controllable rapid cooling. These innovative improvements are all based on specialized inventions made through in-depth exploration of the properties of zinc-silver battery materials. At the same time, these solutions have synergistic effects: the rotating screw drum ensures the consistency of the powder, laying the foundation for pressing qualified electrode plates; non-destructive transfer ensures that the electrode plates are defect-free before sintering; rapid cooling ensures that the testing cycle matches the entire production line; and ultimately, full-process automation is achieved. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of the automatic zinc-silver battery positive electrode plate preparation system of the present invention. The diagram shows the relative positions and material flow directions of the automatic powder weighing device (A), pressing device (B), tunnel sintering device (C), and automatic detection device (D).

[0039] Figure 2 This is a schematic diagram of an automatic weighing device for positive electrode powder, showing the positional relationship between the rotary screw feeding mechanism, the belt powder feeding mechanism, the translation module, the material tray, and the weighing mechanism.

[0040] Figure 3 This is a schematic diagram of an automatic pressing equipment for positive electrode powder, showing the arrangement of the spreading mold, the handling robotic arm, the press, and the vision recording and weighing mechanism.

[0041] Figure 4 This is a schematic diagram of the positive electrode plate tunnel sintering equipment, showing the positional relationship of the upper and lower double-layer circulating conveyor device, sintering furnace, high-temperature heating tube, thermocouple, and air-cooled unit.

[0042] Figure 5 This is a schematic diagram of the structure of an automatic positive electrode plate inspection equipment, showing the layout of the weighing mechanism, vision inspection mechanism, thickness measurement mechanism, inspection and conveying device, and sorting robotic arm.

[0043] Figure 6 This is a photograph showing the state of the powder obtained in Example 1 of the present invention.

[0044] Figure 7 This refers to the agglomerated state of powder obtained using existing technologies.

[0045] Figure 8 The state of powder layering obtained by existing technology.

[0046] Figure 9 This refers to the intact electrode sheet obtained in Example 1 of the present invention.

[0047] Figure 10The damaged electrode sheet is obtained using existing technology.

[0048] The markings in the diagram correspond to the numbers in the instruction manual: Weighing equipment A, Pressing equipment B, Sintering equipment C, Testing equipment D, Observable hopper 1, Rotary screw feeder 2, Belt powder feeding mechanism 3, Translation module 4, Material tray 5, Weighing mechanism No. 1 6, Rotary gripper assembly 7, Feeding rotation assembly 8, Lifting assembly 9, Spreading mold 10, Mold guide rail 11, Handling robotic arm No. 1 12, Handling gripper 13, Press 14, Handling robotic arm No. 2 15, Flexible suction cup 16, Vision positioning module 17, 2 18. Weighing mechanism 19. Visual recording mechanism 20. Demolding completion station 21. Positive electrode plate 22. Positive electrode plate conveying device 23. Positive electrode plate feed port 24. Sintering furnace 25. High temperature heating tube 26. Temperature measuring thermocouple 27. Air-cooled unit 28. Upper transmission device 29. Lower transmission device 30. Positive electrode plate discharge port 31. No. 3 handling robot arm 32. No. 3 weighing mechanism 33. Visual inspection mechanism 34. Thickness measuring mechanism 35. Inspection and conveying device 36. No. 4 handling robot arm 37. Sorting box 38. Detailed Implementation

[0049] The following detailed description illustrates the specific implementation method: Example 1: An automated system for preparing zinc-silver battery positive electrode plates like Figure 1 As shown, this embodiment provides an automated zinc-silver battery positive electrode plate preparation system, comprising four main parts: an automated positive electrode plate powder weighing device A, an automated positive electrode plate powder pressing device B, a positive electrode plate tunnel sintering device C, and an automated positive electrode plate testing device D. The devices are connected in series to form a continuous production line via multiple robotic arms and conveyor components. The entire system is centrally controlled by a host computer, and all process parameters (target weighing values, pressing pressure and holding time, sintering temperature and time, cooling air velocity and temperature, testing thresholds, etc.) are stored according to product model and can be recalled with a single click during production.

[0050] I. Automatic Weighing Equipment for Positive Electrode Plate Powder A like Figure 2 As shown, the automatic weighing equipment A for positive electrode plate powder includes a powder weighing device and a material tray conveying assembly.

[0051] The powder weighing device includes: an observable hopper 1, a rotary screw feeder 2, a belt feeder 3, a translation module 4, a material tray 5, and a weighing mechanism 6. The observable hopper 1 is located above the rotary screw feeder 2, and its side wall has a transparent observation window for easy manual monitoring of the material level. The rotary screw feeder 2 has a rotatable cylinder, driven by rollers, electrodes, a reduction gearbox, and gear transmission (a mature and conventional technology, not detailed here). Spiral blades are fixed to the inner wall of the cylinder. The belt feeder 3 connects to the outlet of the rotary screw feeder 2, and its flat belt is made of TPU (thermoplastic polyurethane), which has good non-adhesiveness and wear resistance. The translation module 4 is located below the belt feeder 3 and drives the belt to move reciprocally in the horizontal direction. The material tray 5 is placed at one end of the translation module 4, and the weighing mechanism 6 is located below the material tray 5 for real-time monitoring of the powder quality within the tray.

[0052] The material tray handling assembly includes: a rotary gripper assembly 7, a feeding rotary assembly 8, and a lifting assembly 9. The rotary gripper assembly 7 is mounted on the feeding rotary assembly 8 and is used to grip the material tray 5; the lifting assembly 9 is connected to the feeding rotary assembly 8 and is used to lift or lower the material tray.

[0053] Work process: After the operator pre-mixes the silver powder and carbon powder according to the process ratio, they add the mixture to the observable hopper 1. The system is then started, and the cylinder of the rotating screw feeding mechanism 2 begins to rotate. The inner spiral blades scoop up the powder from the bottom of the hopper, and as the cylinder rotates to a certain height, the powder naturally falls under gravity and slowly moves towards the outlet along the cylinder's axis. This process involves no extrusion or shearing, preventing cold welding of the silver powder. Any natural stratification that might occur between the silver powder and carbon powder due to density differences is also broken down during continuous tumbling and mixing. The resulting powder... Figure 6 As shown, it exhibits a state of not being layered or clumped.

[0054] The powder falls from the outlet of the rotary screw feeding mechanism 2 onto the TPU flat belt of the belt feeding mechanism 3 below. The translation module 4 drives the flat belt to move horizontally, while the vertical distance between the end of the belt and the material tray 5 is controlled at 2~5mm to achieve low-drop height and flat distribution of the powder. The powder is evenly distributed into the material tray 5, and the No. 1 weighing mechanism 6 reads the total mass of the tray in real time. When the set weighing target value (e.g., 50.00g) is reached, the control system stops feeding. If the powder exceeds the tolerance (e.g., ±0.05g), the system can automatically perform micro-replenishment or rejection.

[0055] After the weighing is qualified, the rotating gripper assembly 7 clamps the material tray 5, the lifting assembly 9 lifts the material tray, and the feeding rotating assembly 8 rotates 180° to transport the material tray 5 to the manual station of the positive electrode plate powder automatic pressing equipment B for use in subsequent processes.

[0056] As an optimization, a capacitive humidity sensor and a drying nitrogen purging device are added to the material hopper. When the humidity sensor detects that the powder moisture content exceeds a set threshold (e.g., relative humidity 40%), the control system automatically activates nitrogen purging. Drying nitrogen is introduced from the bottom of the hopper and gently blows upwards onto the powder until the moisture content drops to a acceptable range. This solution is suitable for production workshops with high ambient humidity.

[0057] II. Automatic pressing equipment for positive electrode plate powder B like Figure 3 and Figure 4 As shown, the automatic pressing equipment B for positive electrode plate powder includes a powder pressing mechanism and a vision recording and weighing mechanism.

[0058] The powder pressing mechanism includes: a spreading mold 10, a mold guide rail 11, a first transport robotic arm 12, a transport gripper 13, and a press 14. The manual workstation includes a receiving position for the material tray 5, a placement platform for the spreading mold 10, and a demolding completion station 20. The mold guide rail 11 extends from the manual workstation into the working range of the first transport robotic arm 12. The spreading mold 10 can slide on the mold guide rail 11. The press 14 is a servo hydraulic press equipped with a pressure sensor and a closed-loop control system, with a pressure control accuracy of ±1%FS. The mold placement platform has embedded heating elements that can preheat the spreading mold 10 to 40℃~60℃ (50℃ in this embodiment).

[0059] The visual recording and weighing mechanism includes: a second handling robotic arm 15, a flexible suction cup 16, a visual positioning module 17, a second weighing mechanism 18, and a visual recording mechanism 19. The flexible suction cup 16 and the visual positioning module 17 are both mounted on the end flange of the second handling robotic arm 15. The second weighing mechanism 18 is placed on the platform of the visual recording mechanism 19 and is used to weigh the pressed electrode plates. Simultaneously, the visual recording mechanism 19 photographs and archives the electrode plates.

[0060] Work process: The feeding rotary assembly 8 transports the material tray 5 containing qualified powder to the manual workstation. The operator takes the powder from the tray and simultaneously takes the pre-prepared metal frame, and according to the process sequence, puts the powder and frame into the preheated spreading mold 10 (preheated to 50°C), and manually spreads the powder using a scraper. After spreading is complete, the operator places the spreading mold 10 at the starting end of the mold guide rail 11 and activates the feeding button. The mold guide rail 11 automatically transfers the mold to the working range of the No. 1 handling robotic arm 12.

[0061] The first robotic arm 12 moves above the spreading mold 10, and the transport gripper 13 picks up the mold and transfers it to the worktable of the press 14. The press 14 presses the mold according to preset parameters (e.g., pressing pressure of 5 tons and holding time of 10 seconds). After pressing, the first robotic arm 12 removes the mold from the press and transports it back to the manual workstation. The operator manually demolds the mold to obtain the positive electrode plate 21 and places it at the demolding completion station 20.

[0062] The vision positioning module 17 at the end of the No. 2 handling robotic arm 15 photographs and identifies the position of the positive electrode plate 21 on the demolding completion station 20, calculating the center coordinates and orientation of the plate. The control system plans an S-shaped acceleration and deceleration trajectory, guiding the flexible suction cup 16 to approach the plate at an extremely low speed (≤5mm / s). Upon contact, a suction force of approximately 0.5N is applied to smoothly pick up the plate. The No. 2 handling robotic arm 15 moves the plate above the No. 2 weighing mechanism 18, releases the suction cup, and the plate falls onto the weighing platform, with the weighing data automatically recorded. Simultaneously, the vision recording mechanism 19 photographs the front and back of the plate for process traceability. After weighing, the No. 2 handling robotic arm 15 picks up the plate again and places it at the positive electrode plate inlet 23 of the positive electrode plate conveying device 22 of the positive electrode plate tunnel sintering equipment C.

[0063] For optimized production, if the production batch is large, two sheeting molds can be configured at the manual workstation for alternating use. While one is pressing in the press, the other is spread by the operator to improve equipment utilization.

[0064] III. Positive Electrode Plate Tunnel Sintering Equipment C like Figure 5 As shown, the positive electrode plate tunnel sintering equipment C includes a positive electrode plate conveying device 22, a sintering furnace 24, a No. 3 handling robotic arm 31, and a flexible suction cup 16 and a visual positioning module 17 installed at the end of the No. 3 handling robotic arm 31.

[0065] The positive electrode plate conveying device 22 adopts a double-layer circulation structure, including a positive electrode plate inlet 23, a positive electrode plate outlet 30, an upper transmission device 28, and a lower transmission device 29. The upper transmission device 28 is used to convey the positive electrode plates from the inlet to the sintering furnace and then from the sintering furnace to the outlet; the lower transmission device 29 is used to return the empty trays or high-temperature resistant pads from the outlet to the inlet, forming a reflux.

[0066] The sintering furnace 24 is located in the middle section of the positive electrode plate conveying device 22. Multiple sets of high-temperature heating tubes 25 and thermocouples 26 are evenly distributed on the top of the furnace cavity, enabling independent temperature control in multiple zones with a temperature uniformity of ≤±5℃. The air-cooled unit 27 is installed directly above the positive electrode plate outlet 30, with its air outlet facing the electrode plate on the conveyor belt. The air speed and air temperature can be adjusted via PLC programming (in this embodiment, the air speed is set to 10m / s and the air temperature is set to 25℃).

[0067] Work process: The No. 2 handling robotic arm (15) places the positive electrode plate on the tray at the positive electrode plate inlet 23. The upper transmission device 28 is activated, sending the tray along with the electrode plate into the sintering furnace 24. The sintering furnace 24 operates according to a set temperature curve (e.g., room temperature to 500℃, heating rate 10℃ / min, holding for 30 minutes, then naturally cooling to 200℃ before entering the air-cooling zone). When the electrode plate moves to the outlet 30 with the upper transmission device, the air-cooling unit 27 automatically starts, forcibly cooling the electrode plate to room temperature (≤30℃) within 10 minutes. The cooled electrode plate remains at the material handling position at the outlet 30.

[0068] Before entering the sintering furnace, the electrode plates are preheated to the optimal temperature according to the process requirements. Timing begins after the electrode plates enter the sintering furnace, and they exit the sintering furnace after the sintering time required by the process.

[0069] The vision positioning module 17 at the end of the No. 3 handling robotic arm 31 identifies the position of the electrode plate. The flexible suction cup 16 smoothly picks up the electrode plate in an S-shaped curve and then transfers it to the starting end of the detection and conveying device 35 of the automatic positive electrode plate detection equipment D. The empty tray continues to move to the end with the upper transmission device, and is transferred to the lower transmission device 29 by the flipping or lifting mechanism, returning to the feed port 23 for use in the next cycle.

[0070] Performance verification: Using the forced air cooling method of this embodiment, the electrode plate cooled from 500°C to room temperature in just 10 minutes, while traditional natural cooling takes about 60 minutes, improving cooling efficiency by 83.3%. Subsequent testing showed that the forced-cooled electrode plate did not exhibit cracks caused by thermal stress, and the sintering quality met aerospace standards.

[0071] IV. Automatic Positive Plate Testing Equipment (D) like Figure 6 As shown, the automatic positive electrode plate detection equipment D includes a detection mechanism and a sorting mechanism.

[0072] The inspection mechanism includes: a weighing mechanism 32, a vision inspection mechanism 33, a thickness measurement mechanism 34, and an inspection conveying device 35. The weighing mechanism 32 uses a high-precision electronic balance with a range of 200g and an accuracy of ±0.05g. The vision inspection mechanism 33 consists of an industrial camera, a ring light source, and an industrial control computer. The industrial control computer is pre-installed with a deep learning-based defect recognition model, capable of identifying four types of defects: cracks, missing edges, deformation, and uneven color. The thickness measurement mechanism 34 uses two coaxial displacement sensors arranged opposite each other, located above and below the inspection conveying device 35 respectively. The sensor measurement accuracy is ±0.001mm, and the plate thickness is obtained through differential calculation. The control system controls the sensors to measure sequentially at five predetermined positions (the four corners and the center of the plate), and the average value is taken as the final thickness.

[0073] The sorting mechanism includes: a No. 4 handling robotic arm 36, a flexible suction cup 16, a vision positioning module 17, and multiple sorting boxes 37. The sorting boxes 37 include at least qualified boxes and unqualified boxes (which can be further subdivided into unqualified weight, unqualified thickness, unqualified appearance, etc.).

[0074] Work process: The No. 3 robotic arm 31 places the sintered and cooled positive electrode plate at the starting end of the testing and conveying device 35. The conveying device then sequentially delivers the electrode plates to each testing station. Weighing station: The plates are conveyed to the weighing platform of weighing mechanism 32. After the load cell stabilizes its reading, the system records the mass data. If the mass exceeds the process requirement range (e.g., 50g ± 0.5g), it is marked as unqualified.

[0075] Appearance inspection station: The electrode plate continues to be conveyed to the vision inspection mechanism 33. An industrial camera captures images of both the front and back of the electrode plate. A deep learning model performs real-time inference and outputs the defect category and confidence level. If the confidence level exceeds a set threshold (e.g., 0.8), the plate is judged to be unqualified in appearance, and the defect type is recorded.

[0076] Thickness Measurement Station: The electrode plate is conveyed to the thickness measurement mechanism at position 34, and the conveying device pauses. Two coaxial displacement sensors contact the electrode plate surface from above and below (contact force ≤ 0.1N). The control system drives the sensors to measure the thickness at five predetermined positions sequentially, calculating the thickness value at each point. If the thickness at any point exceeds the process requirements (e.g., 2.0mm ± 0.05mm), the thickness is deemed unqualified.

[0077] All test data is aggregated into the control system. After testing, the electrode plates are conveyed to the sorting area. The vision positioning module 17 at the end of the No. 4 handling robotic arm 36 identifies the position of the electrode plate, and the flexible suction cup 16 picks it up. Based on the comprehensive judgment result, the control system instructs the robotic arm to place the electrode plates into the corresponding sorting boxes 37: qualified products are placed into qualified product boxes; unqualified products are placed into the corresponding unqualified product boxes according to the defect type (weight / thickness / appearance) for subsequent analysis.

[0078] Performance Verification: Using the automated inspection system of this embodiment, the inspection time for a single electrode plate (including weighing, appearance, thickness measurement, and sorting) is less than 30 seconds. The accuracy rate for identifying appearance defects reaches 99%, and the thickness detection accuracy is ±0.005mm, which is far superior to manual inspection (accuracy rate of approximately 95%, thickness accuracy ±0.05mm). Simultaneously, the inspection data is automatically uploaded to the MES system, enabling quality traceability.

[0079] V. Example of Collaborative Operation of the Entire Production Line Taking a complete production cycle as an example (from powder to finished product for a single electrode plate): T=0 min: The rotary screw feeding mechanism 2 starts feeding, and the weighing is completed in about 30 seconds. The material tray is then transported to the manual work station.

[0080] T=0.5~2 min: manual spreading (about 30 seconds), mold conveying and pressing (holding pressure for 10 seconds, plus auxiliary time for about 40 seconds), demolding (about 10 seconds), weighing and taking pictures by robotic arm No. 2 (about 30 seconds), the total pressing process takes about 2 minutes.

[0081] T=2~2.5 min: Robotic arm No. 2 delivers the electrode plate to the sintering furnace feed inlet (about 15 seconds), and the electrode plate enters the sintering furnace (about 15 seconds).

[0082] T=2.5~24.5 min: The plates are sintered in the sintering furnace (estimated 12 minutes), then enter the air-cooling zone (10 minutes), and cooling is completed at T=24.5 minutes.

[0083] T=24.5~25 min: The electrode plate exits the air-cooled zone (approximately 15 seconds), and the No. 3 robotic arm transfers the electrode plate to the testing equipment (approximately 15 seconds).

[0084] T=25~26 min: The testing equipment completes weighing, appearance, thickness testing and sorting.

[0085] The production cycle for a single piece on the entire line is approximately 26 minutes (from material feeding to sorting). Using traditional manual processes, the time per piece is about 20 minutes (but manual operation relies on skilled workers and cannot be continuous), and with an additional 60 minutes for natural cooling, the actual cycle is even longer. The automated production line of this invention enables continuous production, producing one electrode plate every 30 minutes (due to multiple workstations operating in parallel: during the sintering process, weighing and pressing can simultaneously prepare the next electrode plate), with a daily capacity of approximately 960 plates, a 50% increase compared to the original manual process (480 plates / day).

[0086] VI. Optimal Range of Key Parameters The rotational speed of the rotary screw feeding mechanism 2 is 10~30 rpm, preferably 20 rpm.

[0087] TPU flat belt moving speed: 5~20 mm / s, preferably 10 mm / s.

[0088] The drop height between the material tray and the end of the belt is 5~10 mm, preferably 8 mm.

[0089] Mold preheating temperature: 40℃~60℃, preferably 50℃.

[0090] Pressing pressure: 15~20 tons, preferably 18 tons; Holding time: 5~15 seconds, preferably 10 seconds.

[0091] Sintering temperature: 450℃~550℃, preferably 500℃; sintering time: 10~15 minutes, preferably 12 minutes.

[0092] Air cooling speed: 5~15 m / s, preferably 10 m / s; air temperature: 10℃~30℃, preferably 25℃.

[0093] Flexible suction cup material: silicone rubber or polyurethane, Shore A hardness 30~50.

[0094] S-curve acceleration / deceleration parameters: maximum acceleration ≤ 0.5 m / s² 2 Contact speed ≤ 5 mm / s.

[0095] The above parameters can be adjusted according to different models of zinc-silver battery positive plates (different sizes, thicknesses, and density requirements).

[0096] Example 2: This example describes a variation using alternative solutions to demonstrate the flexibility of the invention.

[0097] Alternative Solution 1: Powder weighing uses vibrating feeder + electromagnetic vibrating trough In environments with low humidity and good powder flowability, electromagnetic vibratory feeding can replace the rotary screw feeder. Specifically, an electromagnetic vibration trough is installed below the discharge port of hopper 1. The amplitude and frequency are adjusted by a frequency converter, causing the powder to move evenly forward along the vibration trough and fall into the material tray 5 below. The translation module 4 drives the material tray to move horizontally, achieving uniform material distribution. This alternative solution has a simpler structure and is suitable for scenarios where the powder is not prone to stratification or where the accuracy requirement is slightly lower (±0.1g).

[0098] Alternative Option 2: Logistics transfer using AGVs + collaborative robotic arms For production line layouts that require frequent adjustments or where multiple product types are produced on the same line, fixed handling robotic arms can be replaced with AGVs (Automated Guided Vehicles) equipped with collaborative robotic arms. The AGVs move along magnetic or laser-guided paths and, upon reaching the designated workstation, the collaborative robotic arms perform pick-up and placement operations. The AGVs communicate with the central control system via a wireless network, enabling flexible scheduling.

[0099] Alternative Option 3: Visual inspection using X-rays or infrared thermal imaging. For applications with extremely high requirements regarding internal defects (such as internal cracks and pores), an X-ray inspection station can be added after the visual inspection unit 33. The X-ray source and detector are placed on opposite sides of the conveying device, and the transmitted images are analyzed by AI algorithms to identify internal defects. Alternatively, infrared thermal imaging can be used: the electrode plate is briefly energized to heat it up, and an infrared camera captures the surface temperature distribution; abnormal temperature areas can indicate internal defects or uneven sintering.

[0100] The above-mentioned alternative solutions are all equivalent variations of the present invention and fall within the protection scope of the present invention.

[0101] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An automated system for preparing zinc-silver battery positive electrode plates, characterized in that, The positive electrode plate is formed by pressing a mixture of silver powder and carbon powder and has a loose and fragile structure; the system includes: An automatic powder weighing device includes a rotary screw feeding mechanism and a belt powder feeding mechanism. The rotary screw feeding mechanism uses the rotation of the cylinder to cause the inner spiral blades to pick up the powder and then let it fall naturally, achieving non-compression and tumbling conveying. The belt powder feeding mechanism uses a non-adhesive flat belt and is used in conjunction with a translation module to achieve low drop height and uniform flat drop. The pressing equipment includes a press and a heating element set in the mold placement table for preheating the mold to 40°C~60°C; The tunnel sintering equipment includes a positive electrode plate conveying device with upper and lower double-layer circulation, a sintering furnace, and an air-cooled unit located above the positive electrode plate discharge port, wherein the air-cooled unit has adjustable wind speed and wind temperature. The automatic inspection equipment includes a weighing mechanism, a thickness measuring mechanism that uses a coaxial displacement sensor to achieve five-point automatic thickness measurement, and a visual inspection mechanism that uses an industrial camera combined with a deep learning algorithm to identify plate defects. Multiple handling robotic arms, each equipped with a flexible suction cup and a vision positioning module at its end, and the motion control of the handling robotic arms adopts S-curve acceleration and deceleration to achieve flexible contact with the electrode plate and smooth transfer.

2. The system according to claim 1, characterized in that, The automatic powder weighing device is also equipped with a capacitive humidity sensor and a dry nitrogen purging device, which are used to monitor the moisture content of the powder in real time and automatically purge when the moisture content exceeds the standard.

3. The system according to claim 1, characterized in that, The flat belt in the belt conveyor is made of TPU material.

4. The system according to claim 1, characterized in that, The press is a servo hydraulic press, equipped with a pressure sensor and a closed-loop control system, and connected to the central control system via industrial Ethernet.

5. The system according to claim 1, characterized in that, In the tunnel sintering equipment, high-temperature heating tubes and thermocouples are evenly distributed on the top of the sintering furnace cavity; the upper and lower double-layer circulating positive electrode plate conveying device includes an upper transmission device and a lower transmission device. The positive electrode plate is fed into the sintering furnace through the upper layer, and after sintering, it is sent to the discharge port through the upper layer. The empty pallet returns to the feeding end through the lower layer.

6. The system according to claim 1, characterized in that, The defects identified by the visual inspection mechanism include cracks, missing edges, deformation, and uneven color.

7. An automated method for preparing a zinc-silver battery positive electrode plate, using the system described in any one of claims 1 to 6, characterized in that, Includes the following steps: Powder weighing steps: The mixture of silver powder and carbon powder is fed into the rotary screw feeding mechanism, and conveyed to the belt powder feeding mechanism through non-extrusion flipping. Then, the belt is driven by the translation module to achieve low drop height and flat drop of the material onto the material tray, and the weighing mechanism weighs it in real time. Pressing steps: The weighed powder and skeleton are put into a mold preheated to 40℃~60℃, spread out, and then transferred to a press to press and shape. After demolding, the positive electrode plate is obtained. Sintering steps: Place the positive electrode plate on the upper layer of the double-layer circulating positive electrode plate conveying device and send it into the sintering furnace for sintering. After sintering, send it to the discharge port through the upper layer and start the air-cooling unit for forced cooling at the same time. Inspection and sorting steps: The sintered positive electrode plates are sequentially sent to the weighing mechanism, visual inspection mechanism and thickness measurement mechanism for weight, appearance and thickness inspection, and automatically sorted according to the inspection results; In all the above transfer processes, the handling robotic arm uses a flexible suction cup to pick up the electrode plate and uses an S-shaped curve acceleration and deceleration to control the motion trajectory.

8. The automatic preparation method for a zinc-silver battery positive electrode plate according to claim 7, characterized in that, In the powder weighing step, when the capacitive humidity sensor detects that the moisture content of the powder exceeds the standard, the drying nitrogen purging device is automatically started to dehumidify.

9. The automatic preparation method for a zinc-silver battery positive electrode plate according to claim 7, characterized in that, The thickness measurement step uses a coaxial displacement sensor to automatically measure the thickness at five measurement points on the surface of the positive electrode plate.

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