A curing process for battery plates

Abstract

The present invention relates to the field of battery manufacturing technology and specifically discloses a curing process for battery plates. The specific steps include: using humidity above 95% and a temperature of 42-50°C to reduce the free lead content of the lead paste to below 14%, thereby promoting the conversion of lead oxide into a tribasic lead sulfate crystalline phase; raising the curing temperature to 65°C and maintaining a humidity of 95% to promote the formation of a tetrabasic lead sulfate crystalline phase; employing a ventilation control strategy to accelerate water evaporation and reduce drying time; and employing a temperature-controlled drying technique to reduce the moisture content to below 0.1%. The present invention shortens the curing time of lead-acid battery plates and enhances the mechanical strength and cycle life of the plates.

Description

Technical Field

[0001] The present invention relates to the technical field of battery manufacturing, and more particularly to a curing process for battery plates. Background Art

[0002] During lead-acid battery manufacturing, the plate curing process is a key step influencing battery performance. The curing process involves oxidation reactions, crystal phase transformation, and plate drying to ensure the adhesion, porosity, and electrochemical stability of the active material.

[0003] Publicly available document 1 (Research on High-Temperature Curing Process for Lead-Acid Battery Positive Plates, 2016) discloses a high-temperature curing process for lead-acid battery positive plates. The process involves preparing samples by varying the curing temperature (80°C, 100°C, 120°C) and curing time (2-10 hours), and then testing the plate and battery performance using a variety of testing methods. The performance of the plates after curing under different conditions, including appearance, composition, structure, and micromorphology, was studied. Internalization experiments, capacity testing, and batch verification were also conducted. The authors analyzed the poor capacity uniformity of batteries cured at high temperatures (80°C for 6 hours) and proposed adding "4BS seed crystals." The effect of this addition on plate and battery performance was experimentally studied. However, when the curing temperature exceeds 100°C, the plate surface may develop bulging, affecting plate stability.

[0004] Publicly available document 2 (Study on the Preparation Process and Battery Performance of Bipolar Plates for Lead-Acid Batteries, 2016) discloses a process for preparing bipolar plates for lead-acid batteries. This process begins by preparing various base materials to create bipolar substrates with varying structures. For example, pure titanium plates are degreased and washed to remove oxide films, while other metal plates are electroplated. Next, a paste is mixed. Short fibers, water, lead powder, and additives are added to the paste mixing vessel, stirred evenly, and the temperature and acid addition rate are controlled to adjust the paste density and consistency. The mixed paste is then applied to the substrate to ensure uniform weight and thickness, followed by an acid treatment. Finally, a low-temperature or high-temperature curing process is used, and the acid-treated plates are placed in a programmable constant temperature and humidity chamber for curing. However, this process involves multiple materials and complex steps, which increases the curing time and makes it unsuitable for large-scale industrial production.

[0005] Therefore, there is an urgent need for a curing process that can shorten the curing time of lead-acid battery plates and improve the stability of lead-acid battery plates. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides a curing process for battery plates, which accelerates the conversion of lead oxide into tribasic lead sulfate crystalline phase through specific temperature and humidity conditions, accelerates water evaporation and reduces drying time by optimizing ventilation control strategy, and adopts temperature-controlled drying technology to avoid cracks caused by excessive drying of the plates, thereby solving the problems raised in the above-mentioned background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A curing process for battery plates comprises the following steps:

[0009] Step S1, using humidity above 95% and temperature of 42-50° C. to reduce the free lead content of the lead paste to below 14%, thereby promoting the conversion of lead oxide into a tribasic lead sulfate crystal phase;

[0010] Step S2: raising the curing temperature to 65° C. and maintaining a humidity of 95% to promote the formation of a tetrabasic lead sulfate crystal phase; and adopting a ventilation control strategy to accelerate water evaporation and reduce drying time.

[0011] Step S3, using temperature-controlled drying technology to reduce the moisture content to below 0.1%, ensuring that the plate is completely dry without cracks;

[0012] The ventilation control strategy includes the following specific steps:

[0013] Step Z1: Deploy humidity sensors in the curing room. Assume that the curing room is divided into N areas. The humidity value of each area is measured by the humidity sensor to obtain the humidity value of each area at time t. : ,in, represents the humidity value at time t in the first area, represents the humidity value at time t in the second area, Represents the humidity value at time t in the Nth region; and calculates the global average humidity value : , Indicates the first regions, For the The humidity value at time t in the area; then the humidity gradient value The calculation formula is: ,like , it means that the humidity in the curing room has reached a balanced state and there is no need to adjust the wind speed and direction. To set the threshold; if , then go to the next step to adjust the wind speed and direction.

[0014] Preferably, in step Z2, a wind speed adjustment model is constructed to control the wind speed adjustment amount so that it can dynamically respond to changes in humidity in the curing chamber to avoid uneven curing effects caused by overly fast or slow adjustments. The calculation formula of the wind speed adjustment model is: ,in, For the The wind speed adjustment amount in the region at time t; For the Time in the region Wind speed adjustment at each moment; It is a proportional control item, reflecting the impact of the current humidity deviation on the wind speed; is the integral control term; Indicates that from the initial moment All historical time steps between now and the current time t; Describe the first Regions in historical time Humidity measurement value at the moment; Indicates historical time The average humidity value in the curing room at the moment; T represents the sampling interval; is the differential control term; It is an adaptive adjustment factor used to adjust the dynamic changes of wind speed. In addition, the wind speed limit is increased to ensure that the wind speed does not exceed the physical safety range: , is the preset minimum allowable wind speed value, It is the preset maximum allowed wind speed value.

[0015] Preferably, in step Z3, in order to optimize the air flow path and reduce the local humidity DC, the wind direction angle adjustment rule is defined: ,in, is the wind direction angle, representing the direction of air flow; Indicates the first The wind direction angle of a region at time t; Indicates the first Regions in time The wind direction at the moment; Adjust the gain for wind direction and control the sensitivity of wind direction changes; when Beyond 0°-180°, adjust the limit: .

[0016] Preferably, the step Z4 adopts closed loop control, recalculates the wind speed and wind direction at each time interval T, and performs the following iterations: 1. Calculates the humidity gradient ; 2. Calculate wind speed adjustment And update the wind speed; 3. Calculate the wind direction adjustment And update the wind direction; 4. Enter the next time step , and continue the cycle.

[0017] Preferably, in step S1, humidity above 95% and temperature conditions of 42-50°C are employed to reduce the free lead content of the lead paste to below 14%, while promoting the conversion of lead oxide to a tribasic lead sulfate crystalline phase. Specifically, the process involves ensuring the humidity of the lead paste is between 10-14% to ensure uniform coating of the active material. Freshly coated lead paste plates are neatly arranged on a metal bracket or dedicated curing rack to ensure even airflow distribution across all plates, thereby avoiding localized under- or over-curing. The plates are then placed in a curing chamber, where the temperature is set between 42-50°C to prevent excessive dehydration of the lead paste due to high temperatures or a decrease in the hydration reaction rate of lead oxide (PbO) due to low temperatures. Simultaneously, the humidity of the curing chamber is maintained above 95% using a water spray humidification system to prevent rapid evaporation of moisture from the lead paste, instead gradually participating in the hydration and sulfation reactions of the PbO.

[0018] Preferably, in the initial stage of the curing process, PbO in the lead paste first combines with moisture to form lead hydroxide (Pb(OH)2), and then, under the action of sulfuric acid vapor, Pb(OH)2 is gradually converted into tribasic lead sulfate (3BS).

[0019] Preferably, in step S2, the curing temperature is raised to 65°C and the humidity is maintained at 95% to promote the formation of the tetrabasic lead sulfate crystalline phase. An optimized ventilation control strategy is adopted to accelerate water evaporation and reduce drying time. The steps include gradually increasing the temperature of the curing chamber from 42-50°C to 65°C within 4-6 hours to ensure that the temperature increase does not cause rapid water loss on the plate surface, thereby affecting the uniformity of curing. At the same time, the humidity must still be maintained above 95% to ensure that the hydration reaction within the lead paste proceeds smoothly, and that the bonding strength between the lead paste particles is not reduced due to excessive water evaporation, thereby affecting the structural stability of the plate.

[0020] Preferably, in order to accelerate the evaporation of water while preventing the plate surface from drying out too quickly and causing cracking that affects the curing quality, a ventilation control strategy is adopted.

[0021] Preferably, in step S3, temperature-controlled drying technology is used to reduce the moisture content to below 0.1%, ensuring that the plates are completely dry and crack-free. The temperature-controlled drying technology comprises three stages: a pre-drying stage, a medium-temperature diffusion drying stage, and a uniform drying stage. This ensures uniform moisture removal from the plates during the drying process and prevents structural damage caused by rapid temperature increases. During the pre-drying stage (0-8 hours), the plates are placed in a drying chamber with high humidity (>35% RH) and low temperature (40-50°C). The primary purpose of this stage is to promote moisture diffusion from the interior of the plates to the outside through capillary action, while reducing the moisture gradient within the plates to prevent rapid evaporation of surface moisture, which could lead to surface hardening. During the medium-temperature diffusion drying stage (8-24 hours), the drying temperature is gradually increased to 60-70°C, and the humidity is reduced to 15-25% RH. The goal of this stage is to accelerate moisture diffusion and the dehydration process. To further optimize the moisture diffusion rate, an intermittent heating strategy was implemented: increasing the temperature by 5°C every 2-4 hours while simultaneously reducing the humidity by 5% to keep the dehydration rate consistent with the moisture diffusion rate. During the uniform drying phase (24-32 hours), the drying temperature was maintained at 75-80°C, the humidity was reduced to 5-10% RH, and a convection air system was used to accelerate moisture evaporation. At this point, the moisture content of the plates dropped to approximately 1.0%, but further drying was required to ensure the moisture content dropped below 0.1%. During this phase, the wind speed was initially increased to 1.5-2.0 m / s to accelerate moisture evaporation, then gradually reduced to 0.8 m / s over the final four hours to prevent surface cracking caused by excessive wind. Furthermore, to ensure temperature uniformity, infrared thermal imaging technology was used throughout the drying process to monitor the temperature distribution on the plate surface in real time. If local temperature deviations exceeding ±2°C were detected, the heating element position or air flow direction was adjusted to ensure uniform heating across the plates, further reducing thermal stress and preventing microcracks.

[0022] The technical effects and advantages of the curing process of a battery plate of the present invention are as follows:

[0023] In the initial stage, specific temperature and humidity conditions (above 95% humidity and 42-50°C) accelerate the conversion of lead oxide to a tribasic lead sulfate crystalline phase, reduce the free lead content, and improve curing efficiency, completing this curing phase in a shorter time than conventional processes. Raising the temperature to 65°C and maintaining high humidity not only promotes the formation of a tetrabasic lead sulfate crystalline phase, improving the conductivity and mechanical strength of the plates, but also optimizes the ventilation control strategy by dynamically adjusting wind speed and direction based on the humidity gradient, accelerating water evaporation and reducing drying time, increasing the water evaporation rate by approximately 30%. The final temperature-controlled drying technology utilizes three stages: pre-drying, medium-temperature diffusion drying, and uniform drying. Controlling temperature, humidity, and air flow prevents cracking caused by excessive drying of the plates and ensures uniform water removal. This invention significantly shortens the curing time of lead-acid battery plates, improves plate stability, and enhances their mechanical strength and cycle life, thereby extending the battery's service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a flow chart of a method for curing a battery plate.

[0025] Figure 2 This is a schematic diagram comparing the porosity of positive plates under different curing conditions in the high-temperature curing process of lead-acid battery positive plates in the prior art.

[0026] Figure 3 The present invention is a flow chart of the preparation process of a bipolar lead-acid battery in the prior art process of preparing bipolar plates for lead-acid batteries.

[0027] Figure 4 Schematic diagram showing the change of 3BS generation rate over time according to the present invention.

[0028] Figure 5 Schematic diagram of the effect of the ventilation control strategy of the present invention on the water evaporation rate. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] Example 1

[0031] See Figure 1 As shown in the flowchart, an embodiment of the present invention provides a curing process for a battery plate, which includes the following steps:

[0032] In step S1, a humidity of 95% or higher and a temperature of 42-50° C. are used to reduce the free lead content of the lead paste to below 14%, thereby promoting the conversion of lead oxide into a tribasic lead sulfate crystal phase.

[0033] In step S2, the curing temperature is increased to 65° C., and the humidity is maintained at 95% to promote the formation of a tetrabasic lead sulfate crystal phase. A ventilation control strategy is adopted to accelerate water evaporation and reduce drying time.

[0034] In step S3, temperature-controlled drying technology is used to reduce the moisture content to below 0.1%, ensuring that the plate is completely dry without cracks.

[0035] In this embodiment, see Figure 2 The schematic diagram shown is a prior art high-temperature curing process for lead-acid battery positive plates. The specific steps of this process are as follows: Samples were prepared by setting curing temperatures (80°C, 100°C, 120°C) and times (2-10 hours), and the plate and battery performance were tested using a variety of testing methods. The performance of the plates after curing under different conditions was studied, including appearance, composition, structure, and micromorphology. Internalization experiments, capacity testing, and batch verification were also conducted. To address the issue of poor capacity uniformity in batteries cured at high temperatures (80°C x 6 hours), the cause was analyzed and a solution of adding "4BS seed crystals" was proposed. Its effect on plate and battery performance was experimentally studied. However, when the curing temperature reaches above 100°C, the plate surface will develop a "bulging" phenomenon, affecting the plate's stability. Figure 3 The flowchart shown is a prior art process for preparing bipolar plates for lead-acid batteries. This process begins by preparing various base materials to create bipolar substrates with varying structures. For example, pure titanium plates are degreased and washed to remove oxide films, while other metal plates are electroplated. Next, a paste is prepared by sequentially adding short fibers, water, lead powder, and additives to a mixing vessel, stirring evenly. The temperature and acid addition rate are controlled to adjust the density and consistency of the lead paste. The prepared lead paste is then applied to the substrate to ensure uniform weight and thickness, followed by an acid treatment. Finally, a low- or high-temperature curing process is employed, with the acid-treated plates placed in a programmable constant temperature and humidity chamber for curing. However, this process involves multiple materials and complex steps, which increases curing time and is unsuitable for large-scale industrial production.

[0036] In step S1, humidity above 95% and temperature conditions of 42-50°C are used to reduce the free lead content of the lead paste to below 14%, while promoting the conversion of lead oxide to a tribasic lead sulfate crystalline phase. The process involves: first, ensuring the humidity of the lead paste is between 10-14% to ensure uniform coating of the active material and maintain good adhesion and porosity during the subsequent curing process. Freshly coated lead paste plates are neatly arranged on a metal bracket or dedicated curing rack to ensure even airflow distribution across all plates, thereby avoiding localized under- or over-curing. The plates are then transferred to a curing chamber, where the temperature is set between 42-50°C to prevent excessive dehydration of the lead paste due to high temperatures or a decrease in the hydration reaction rate of lead oxide (PbO) due to low temperatures. Simultaneously, the humidity in the curing chamber is maintained above 95% using a water spray humidification system to prevent rapid evaporation of moisture from the lead paste, instead gradually participating in the hydration and sulfation reactions of the PbO.

[0037] In the initial stage of the curing process, PbO in the lead paste first combines with water to form lead hydroxide (Pb(OH)2), and then, under the action of sulfuric acid vapor, Pb(OH)2 is gradually converted into tribasic lead sulfate (3BS). Figure 4 The graph shows that the 3BS formation rate is optimized under conditions of humidity above 95% and temperatures between 42 and 50°C. As can be seen from the graph, at 95% humidity and 42-50°C, the 3BS crystal phase forms rapidly, reaching over 85% after approximately 8 hours. At 5% humidity and 35-40°C, the 3BS crystal phase forms more slowly, requiring 12 hours to reach 85%. Within the first 8 hours of curing, a high proportion of 3BS crystals forms on the plate surface and within the plate, while the free lead content (FLC%) in the lead paste rapidly decreases from an initial 22-25% to below 14%. Table 1 below provides the specific experimental data.

[0038] Table 1 Comparison of 3BS formation and free lead (FLC%) reduction rate during lead-acid battery plate curing process

[0039] Time (hours) 3BS formation ratio (%)-optimized process 3BS formation ratio (%) - traditional process Free Lead Content (FLC%)-Optimized Process Free Lead Content (FLC%)-Traditional Process 0 0 0 24 25 1 5 2 22 24 2 12 5 19 22 3 22 10 17 21 4 35 18 15 19 5 50 28 14 17 6 65 40 13.5 16 7 78 55 13 15 8 85 70 12.8 14.5

[0040] The optimized process in Table 1 operates at 95% humidity and a temperature of 42-50°C; the conventional process operates at 85% humidity and a temperature of 35-40°C. Experiments have shown that using humidity above 95% and a temperature of 42-50°C significantly accelerates the formation of the 3BS crystal phase and improves plate curing efficiency. Within 8 hours, the optimized process can reduce FLC% to below 14%, meeting the rapid curing target. The conventional process requires significantly longer to achieve the same effect.

[0041] In step S2, the curing temperature is raised to 65°C and the humidity is maintained at 95% to promote the formation of tetrabasic lead sulfate crystals. An optimized ventilation control strategy is used to accelerate water evaporation and reduce drying time. This includes gradually increasing the temperature of the curing chamber from 42-50°C to 65°C. This temperature increase process is completed within 4-6 hours to ensure that the temperature increase does not cause rapid water loss on the plate surface, which would affect the curing uniformity. At the same time, the humidity must still be maintained above 95% to ensure that the hydration reaction within the lead paste proceeds smoothly, and that the bonding strength between the lead paste particles is not reduced due to excessive water evaporation, which would affect the structural stability of the plate.

[0042] In this embodiment, research shows that maintaining a high humidity environment helps reduce the adverse reaction of PbO directly forming PbSO4, allowing it to be converted into more 4BS, thereby improving the conductivity and mechanical strength of the cured plate. Table 2 below shows experimental data on the effect of different humidity environments on the conversion of PbO to 4BS.

[0043] Table 2 Analysis of PbO conversion rate and PbSO4 generation

[0044] humidity(%) 4BS content (%) <![CDATA[PbSO4 content]]> PbO residue (%) 85 52.3 24.5 23.2 90 65.1 19.2 15.7 95 78.4 12.1 9.5 98 80.1 10.3 9.6

[0045] As shown in Table 2, at a humidity of 85%, the conversion rate of PbO is low and the amount of PbSO4 formed is high, reaching 24.5%. This indicates that low humidity easily causes PbO to react directly with sulfuric acid to form PbSO4 instead of 4BS. As the humidity increases to 95%, the conversion rate of PbO increases significantly to 78.4%, while the content of PbSO4 decreases to 12.1%, indicating that higher humidity helps inhibit the formation of PbSO4 and preferentially converts PbO to 4BS. At a humidity of 98%, the content of 4BS (80.1%) is basically stable, and the residual PbO is low (9.6%). This indicates that when the humidity is too high, the conversion efficiency is close to saturation, which will not significantly increase the proportion of 4BS, but is still beneficial to inhibit the formation of PbSO4.

[0046] Table 3 below shows the conductivity of lead-acid battery plates in different humidity environments.

[0047] Table 3 Electrode conductivity analysis

[0048] humidity(%) Conductivity (mS·cm⁻¹) 85 2.8 90 3.4 95 4.2 98 4.3

[0049] Table 3 shows that at 85% humidity, the conductivity of the plate is the lowest (2.8 mS·cm⁻¹), which may be because the formation of more PbSO4 hinders the transmission of electrons and ions; at 95% humidity, the conductivity reaches 4.2 mS·cm⁻¹, indicating that high humidity promotes the formation of 4BS and improves the conductivity of the plate; the conductivity at 98% humidity is not much different from that at 95%, indicating that after the humidity exceeds 95%, the improvement in conductivity tends to saturate.

[0050] Table 4 below shows the mechanical strength of lead-acid battery plates in different humidity environments.

[0051] Table 4 Mechanical strength analysis of electrode plates

[0052] humidity(%) Flexural strength (MPa) 85 4.5 90 5.8 95 7.3 98 7.4

[0053] Table 4 shows that at 85% humidity, the flexural strength of the plate is low (4.5 MPa), which may be due to the high proportion of PbSO4, resulting in a fragile plate structure; at 95% humidity, the flexural strength is the highest (7.3 MPa), which indicates that the formation of 4BS enhances the mechanical stability of the plate; at 98% humidity, the flexural strength does not change much (7.4 MPa), and further increasing the humidity has limited contribution to the mechanical strength of the plate.

[0054] In order to accelerate the evaporation of water while preventing the plate surface from drying out too quickly and causing cracks that affect the curing quality, a ventilation control strategy needs to be adopted, including the following specific steps:

[0055] Step Z1: Deploy humidity sensors in the curing room. Assume that the curing room is divided into N areas. The humidity value of each area is measured by the humidity sensor to obtain the humidity value of each area at time t. : ,in, represents the humidity value at time t in the first region, represents the humidity value at time t in the second area, Represents the humidity value at time t in the Nth region; and calculates the global average humidity value : , Indicates the first regions, For the The humidity value at time t in the area; then the humidity gradient value The calculation formula is: ,like , it means that the humidity in the curing room has reached a balanced state and there is no need to adjust the wind speed and direction. To set the threshold; if , then go to the next step to adjust the wind speed and direction.

[0056] Step Z2: Construct a wind speed adjustment model to control the wind speed adjustment amount so that it can dynamically respond to changes in humidity in the curing room and avoid the problem of uneven curing effect caused by adjusting too fast or too slow. The calculation formula of the wind speed adjustment model is: ,in, For the The wind speed adjustment amount in the region at time t; For the Time in the region Wind speed adjustment at each moment; It is a proportional control item, reflecting the impact of the current humidity deviation on the wind speed; is the integral control term; Indicates that from the initial moment All historical time steps between now and the current time t; Describe the first Regions in historical time Humidity measurement value at the moment; Indicates historical time The average humidity value in the curing room at the moment; T represents the sampling interval; is the differential control term; It is an adaptive adjustment factor used to adjust the dynamic changes of wind speed. In addition, the wind speed limit is increased to ensure that the wind speed does not exceed the physical safety range: , is the preset minimum allowable wind speed value, It is the preset maximum allowed wind speed value.

[0057] Step Z3: To optimize the air flow path and reduce local humidity DC, define the wind direction adjustment rules: ,in, is the wind direction angle, representing the direction of air flow; Indicates the first The wind direction angle of a region at time t; Indicates the first Regions in time The wind direction at the moment; Adjust the gain for wind direction and control the sensitivity of wind direction changes; when Beyond 0°-180°, adjust the limit: .

[0058] Step Z4, using closed-loop control, recalculate the wind speed and direction at each time interval T and perform the following iterations: 1. Calculate the humidity gradient ; 2. Calculate wind speed adjustment And update the wind speed; 3. Calculate the wind direction adjustment And update the wind direction; 4. Enter the next time step , and continue the cycle.

[0059] See Figure 5As shown in the graph, after adopting the optimized ventilation strategy, the water evaporation rate increased by about 30%, allowing water to diffuse more evenly from the inside of the plate to the outside, accelerating water evaporation and reducing drying time.

[0060] In step S3, temperature-controlled drying technology is used to reduce the moisture content to below 0.1%, ensuring complete drying of the plates without cracking. This temperature-controlled drying technology comprises three stages: a pre-drying stage, a medium-temperature diffusion drying stage, and a uniform drying stage. This ensures uniform moisture removal from the plates during the drying process and prevents structural damage caused by rapid temperature increases. During the pre-drying stage (0-8 hours), the plates are placed in a drying chamber with high humidity (>35% RH) and low temperature (40-50°C). This stage primarily aims to promote moisture diffusion from the interior of the plates through capillary action, while also reducing the moisture gradient within the plates to prevent rapid evaporation of surface moisture and resulting in surface hardening. During the medium-temperature diffusion drying stage (8-24 hours), the drying temperature is gradually increased to 60-70°C, while the humidity is reduced to 15-25% RH. This stage aims to accelerate moisture diffusion and the dehydration process. To further optimize the moisture diffusion rate, an intermittent temperature increase strategy is employed: increasing the temperature by 5°C and simultaneously reducing the humidity by 5% every 2-4 hours to keep the dehydration rate consistent with the moisture diffusion rate. During the uniform drying stage (24-32 hours), the drying temperature is controlled at 75-80°C, the humidity is reduced to 5-10%RH, and the evaporation of water is accelerated by the air convection system. At this point, the moisture content of the plate has dropped to about 1.0%, but further drying is still required to ensure that the moisture content drops below 0.1%. During this stage, the wind speed is first increased to 1.5-2.0m / s to accelerate water evaporation, and then gradually reduced to 0.8m / s in the last 4 hours to avoid the formation of surface cracks due to excessive wind force. In addition, to ensure uniform temperature, infrared thermal imaging monitoring technology is also used in the drying process to monitor the temperature distribution on the surface of the plate in real time. When local temperature deviation exceeds ±2°C, the position of the heating element or the air flow direction is adjusted to ensure uniform heating of the plate, further reduce thermal stress, and prevent the formation of microcracks.

[0061] In the initial stage, the present invention utilizes specific temperature and humidity conditions (above 95% humidity and 42-50°C) to accelerate the conversion of lead oxide to a tribasic lead sulfate crystalline phase, reduce the free lead content, and improve curing efficiency, completing this curing phase in a shorter time than conventional processes. Raising the temperature to 65°C and maintaining high humidity not only promotes the formation of a tetrabasic lead sulfate crystalline phase, improving the conductivity and mechanical strength of the plate, but also optimizes the ventilation control strategy by dynamically adjusting wind speed and direction based on the humidity gradient, accelerating water evaporation and reducing drying time, increasing the water evaporation rate by approximately 30%. The final temperature-controlled drying technology utilizes three stages: pre-drying, medium-temperature diffusion drying, and uniform drying. This controls temperature, humidity, and air flow to prevent cracking caused by excessive drying of the plate and ensure uniform water removal. This invention significantly shortens the curing time of lead-acid battery plates, improves plate stability, and enhances the mechanical strength and cycle life of the plates, thereby extending the battery's service life.

[0062] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A curing process for battery plates, characterized in that: The steps include: Step S1, using humidity above 95% and temperature of 42-50° C. to reduce the free lead content of the lead paste to below 14%, thereby promoting the conversion of lead oxide into a tribasic lead sulfate crystal phase; Step S2: raising the curing temperature to 65° C. and maintaining a humidity of 95% to promote the formation of a tetrabasic lead sulfate crystal phase; and adopting a ventilation control strategy to accelerate water evaporation and reduce drying time. Step S3, using temperature-controlled drying technology to reduce the moisture content to below 0.1%, ensuring that the plate is completely dry without cracks; The ventilation control strategy includes the following specific steps: Step Z1: Deploy humidity sensors in the curing room to calculate the global average humidity value ; Step Z2: construct a wind speed adjustment model to control the wind speed adjustment amount. The calculation formula is: ,in, For the Time in the region Wind speed adjustment at each moment; For the Time in the region Wind speed adjustment at each moment; is the proportional control term; For the within the region Humidity value at the moment; is the integral control term; represents the historical time step; Describe the first Regions in historical time Humidity measurement value at the moment; Indicates historical time Average humidity value in the curing room at all times; Indicates the sampling interval; is the differential control term; is the adaptive adjustment factor; Step Z3: In order to optimize the air flow path and reduce the local humidity DC, define the wind direction angle adjustment rules.

2. A curing process for battery plates according to claim 1, characterized in that , the global average humidity value The calculation formula is: , Indicates the first regions, For the within the region The humidity value at the moment; the humidity gradient value The calculation formula is: 。 3. A curing process for battery plates according to claim 1, characterized in that , the adjustment rule of the wind direction angle is: ,in, is the wind direction angle, representing the direction of air flow; Indicates the first Regions in time The wind direction at the moment; Indicates the first Regions in time The wind direction at the moment; Adjust the gain for wind direction and control the sensitivity of wind direction changes; when Beyond 0°-180°, adjust the limit: .

4. A curing process for battery plates according to claim 1, characterized in that: In step S1, the humidity of the lead paste is between 10-14%, the freshly coated lead paste plates are arranged on a metal bracket, the temperature in the curing chamber is set at 42-50°C, and the humidity in the curing chamber is set to above 95% by a water spray humidification system.

5. The curing process of a battery plate according to claim 1, characterized in that: In step S1, under conditions of 95% humidity and 42-50° C., lead oxide first combines with water to form lead hydroxide, which is then converted into tribasic lead sulfate under the action of sulfuric acid vapor. Within 8 hours before curing, the proportion of tribasic lead sulfate crystal phase formation reaches more than 85%, and the free lead content is reduced from 22-25% to less than 14%.

6. The curing process of a battery plate according to claim 1, characterized in that: In step S2, the temperature of the curing chamber is gradually increased from 42-50°C to 65°C within 4-6 hours, and the humidity is maintained at 95%.

7. The curing process of a battery plate according to claim 1, characterized in that: In step S3, the temperature-controlled drying technology includes a pre-drying stage, a medium-temperature diffusion drying stage, and a uniform drying stage.

8. A curing process for battery plates according to claim 7, characterized in that: In the pre-drying stage, the electrode plates are placed in a drying chamber with a humidity greater than 35% RH and a temperature of 40-50°C, and capillary action is used to promote the diffusion of moisture from the inside of the electrode plates to the outside. In the medium-temperature diffusion drying stage, the drying temperature is gradually increased to 60-70°C, and the humidity is reduced to 15-25% RH. An intermittent heating strategy is adopted, increasing the temperature by 5°C and simultaneously reducing the humidity by 5% every 2-4 hours. In the uniform drying stage, the drying temperature is controlled at 75-80°C, and the humidity is reduced to 5-10% RH. The wind speed is first increased to 1.5-2.0m / s, and then gradually reduced to 0.8m / s within the last 4 hours.

9. The curing process of a battery plate according to claim 7, characterized in that: The uniform drying stage uses infrared thermal imaging monitoring technology to monitor the surface temperature distribution of the plate in real time. When the local temperature deviation exceeds ±2°C, the position of the heating element or the air flow direction is adjusted.

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