Manufacturing method of high-specific-energy lead-carbon battery

Abstract

The invention relates to the technical field of lead-carbon battery manufacturing, in particular to a high-specific-energy lead-carbon battery manufacturing method which comprises the following steps: S1, screening and pretreating a carbon material; s2, preparing lead carbon negative electrode paste; s3, preparing and casting a grid alloy; s4, plate coating and curing; s5, assembling a plate group; s6, packaging and welding a battery shell; s7, electrolyte filling and container formation are carried out; and S8, performing performance detection and aging. According to the scheme, when the lead-carbon negative electrode paste is prepared, firstly, strict pickling purification and high-strength ultrasonic dispersion treatment are carried out on a carbon material with a high specific surface area, so that impurities on the surface of carbon are thoroughly removed, a uniform and stable dispersion liquid is formed in water, and a solid foundation is laid for full combination of the carbon material and lead powder; then, a step-by-step gradient mixing strategy is adopted, the carbon dispersion liquid, dry powder and sulfuric acid are mixed in stages under the condition of multiple rotating speeds, precise temperature control is supplemented, it is ensured that active substances, carbon additives and fibers are evenly distributed, and agglomeration is effectively prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lead-carbon battery manufacturing, in particular to a high specific energy lead-carbon battery manufacturing method. BACKGROUND

[0002] As an advanced chemical power source combining the characteristics of traditional lead-acid batteries and supercapacitors, lead-carbon batteries have a broad application prospect in the fields of new energy vehicle start-stop systems, hybrid electric vehicles, energy storage and backup power sources due to their excellent partial state of charge cycle life, high power output capability and good low temperature performance.

[0003] Currently, carbon materials are difficult to disperse uniformly in the lead paste system due to their extremely high specific surface area and strong hydrophobicity, and are prone to agglomeration, which not only reduces the utilization rate of carbon materials, but also leads to uneven distribution of active materials and discontinuous conductive network in the negative plate, thereby causing problems such as increased internal resistance, low active material utilization rate, decreased rate performance and shortened cycle life.

[0004] At the same time, the preparation of lead-carbon negative paste is a complex physicochemical process involving lead powder oxidation, lead sulfate crystallization, paste thickening, etc. The introduction of carbon materials changes the rheological properties and reaction kinetics of the system. If the process is not properly controlled, it is easy to cause problems such as unstable paste apparent density, severe heat generation during paste mixing, poor paste coatability, poor consistency of the cured plate, etc. The existing process lacks fine and coordinated control of key parameters such as carbon material pretreatment, feeding sequence, mixing gradient, temperature and vacuum degree.

[0005] Secondly, in order to match the high conductivity, lightweight and strong corrosion resistance requirements of the grid for high specific energy lead-carbon batteries, traditional high-antimony alloy grids are no longer suitable due to their low hydrogen and oxygen evolution potential, large water loss and other shortcomings, while low-antimony or antimony-free lead-calcium-tin-aluminum alloys are a better choice. However, the calcium and other elements in this type of alloy are prone to oxidation and burning during smelting, resulting in composition fluctuations. The fluidity of the alloy during casting is different from that of traditional alloys, which is prone to casting defects. Moreover, the interface bonding state between the alloy and the active material directly affects the battery performance, and the existing grid manufacturing process still has deficiencies in alloy smelting protection, process composition accurate control, defect automatic detection and surface pretreatment to optimize the interface bonding. SUMMARY

[0006] In order to overcome the above technical problems or at least partially solve the above problems, the present application provides a high specific energy lead-carbon battery manufacturing method.

[0007] The present application provides a high specific energy lead-carbon battery manufacturing method, which is as follows: S1, selection and pretreatment of carbon materials, selecting carbon materials with high specific surface area such as activated carbon, graphene and carbon nanotubes; S2, preparation of lead-carbon negative electrode paste, pretreated carbon material is mixed with lead powder, sulfuric acid, short fibers, expanding agent and deionized water by high-speed stirring to form a uniform lead-carbon paste; S3, preparation and casting of grid alloy, low-antimony or antimony-free alloy such as lead-calcium-tin-aluminum is melted in a furnace, and then cast into light grids by gravity casting or stretching grid process; S4, coating and curing, the coated wet plate is placed in a high-temperature and high-humidity curing room; S5, assembly of the group, the positive plate, negative plate and AGM separator after drying and curing are stacked alternately, and then welded together by busbars to form a group; S6, battery shell packaging and welding, the assembled group is placed in a battery tank, and the battery cover is covered, and the sealing is ensured by heat sealing or epoxy adhesive, and the pole is welded and connected with the terminal on the cover; S7, electrolyte filling and internal formation, the accurately measured dilute sulfuric acid electrolyte is injected into the battery by a vacuum liquid filling machine; S8, performance detection and aging, the formed battery is detected for open circuit voltage, internal resistance, capacity and large current discharge characteristics, and the qualified products are selected, then the battery voltage and performance are stabilized by standing aging, and finally the battery is cleaned, labeled and packaged.

[0008] Preferably, the preparation of the lead-carbon negative electrode paste in S2 further comprises step-by-step pretreatment, gradient mixing and process precision control, and the step-by-step pretreatment is the pretreatment and activation of carbon fibers, specifically: S2.1.1, the selected high specific surface area activated carbon or carbon nanomaterial is placed in a dilute nitric acid or dilute sulfuric acid solution, and stirred at 60-80 degrees for 2-4 hours; S2.1.2, the acid-washed carbon material is repeatedly washed with a large amount of deionized water until it is neutral, and then placed in a vacuum drying oven at 120 degrees for thorough drying to ensure no water residue; S2.1.3, the pretreated and dried carbon material is mixed with part of the deionized water in the formula and an appropriate amount of dispersant, and high-intensity ultrasonic treatment is carried out by using an ultrasonic cell disruptor to form a uniform and stable carbon material aqueous dispersion.

[0009] Preferably, the gradient mixing is step-by-step gradient mixing and paste reaction control, specifically: S2.2.1, all the required lead powder, short fibers and expanding agent are first put into a double-shaft vacuum and paste machine; S2.2.2, the carbon material dispersion prepared in the first step is mixed with the remaining deionized water, and slowly added to the dry mixture being stirred at low speed; S2.2.3, the sulfuric acid of a specified concentration is added to the slurry in multiple times and slowly, and the cooling system of the paste machine is started at the same time.

[0010] Preferably, the process is precisely controlled for vacuum degassing and paste performance regulation, specifically: S2.3.1, immediately after high-speed stirring, turn on the vacuum system of the mixing machine, and run for 5-8 minutes at medium-low speed; S2.3.2, take out a small amount of paste and use a paste visual density meter to detect its visual density, and use hands or a scraper to check the consistency of the paste; S2.3.3, take out the prepared lead-carbon paste from the mixing machine and place it in a sealed container for at least 2 hours of aging before coating the plate.

[0011] Preferably, the preparation and casting of the grid alloy in S3 also includes smelting optimization, quality detection and surface treatment, and the smelting optimization specifically includes: S3.1.1, introduce inert gas or cover special protective salt above the furnace to form a protective atmosphere, which can minimize the oxidation loss of alloy elements; S3.1.2, use a closed continuous feeding system to automatically add pure lead ingots, master alloy and aluminum wire to the furnace according to the proportion; S3.1.3, use an online spectral analyzer to detect the composition of the molten alloy at regular intervals, and automatically adjust the feeding ratio based on the feedback data.

[0012] Preferably, the quality detection specifically includes: S3.2.1, install a high-speed camera on the production line to detect the appearance of each cast grid or continuous grid, automatically identify and remove products with defects such as burrs, cracks and flash; S3.2.2, 100% online weighing and key point laser thickness measurement of finished grid to ensure that its weight and size tolerance meet the strict requirements of lightweight design, and the data is recorded simultaneously for traceability.

[0013] Preferably, the surface treatment specifically includes: S3.3.1, remove grease and dirt from the surface of the grid by alkaline solution, and then slightly etch it by dilute acetic acid or citric acid solution to remove the thin oxide layer and expose the fresh metal surface; S3.3.2, electrochemical treatment of the grid to form a thin and dense PbO2 or specific oxide film on its surface.

[0014] Preferably, in S2.1.3, the deionized water accounts for one-third of the total weight, the dispersing agent is polyethylene glycol PEG, the power of ultrasonic treatment is set to 800W, and the duration is 30 minutes.

[0015] Preferably, in S2.2.1, the low-speed stirring speed is 100-200 rpm, and dry mixing is performed for 5-10 minutes; The stirring in S2.2.2 is 300-400 rpm from low speed to medium speed, and wet mixing for 10-15 minutes.

[0016] Preferably, the sulfuric acid in S2.2.3 is added in batches, and the batch is subdivided as follows: First batch of sulfuric acid: a small amount of sulfuric acid is added, stirred at medium speed, and the temperature of the paste is observed to slowly rise to a preset value, controlled at 40 degrees; Subsequent batches: control the acid addition rate to keep the paste temperature between 45-55 degrees; After all the sulfuric acid is added, switch to high-speed stirring at 500-600 rpm for homogenization, and the duration is 3-5 minutes.

[0017] The targeted scheme provided by the present application has the following beneficial effects: 1. In the preparation of the lead-carbon negative paste, the high specific surface area carbon material is first subjected to strict acid washing purification and high-strength ultrasonic dispersion treatment, which completely removes the impurities on the surface of the carbon and forms a uniform and stable dispersion in water, laying a solid foundation for the full combination of the carbon material and lead powder. Then, a step-by-step gradient mixing strategy is adopted to mix the carbon dispersion, dry powder, and sulfuric acid in multiple rotation speeds, and precise temperature control is applied to ensure the uniform distribution of active materials, carbon additives, and fibers, effectively preventing agglomeration. 2. As described in 1, by using low-antimony or antimony-free lead-calcium-tin-aluminum alloy and passing a protective atmosphere during smelting and online spectral monitoring, the accuracy and stability of the alloy composition are ensured, the mechanical strength and corrosion resistance of the grid are improved from the source, and the cast grid is subjected to 100% automatic visual detection and size control to ensure the accurate realization of the lightweight design. 3. As described in 2, a thin and dense pre-formed oxide film is generated on the surface of the grid skeleton through subsequent chemical cleaning and electrochemical surface treatment, which significantly enhances the interfacial bonding force between the grid and the active material paste, reduces the interfacial contact resistance, and enables the battery to withstand higher-rate large current discharge while achieving weight reduction, exhibiting excellent high-power output characteristics. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0019] Fig. 1 is the flow chart of the high specific energy lead-carbon battery provided by the embodiments of the present application; Fig. 2 The gradient mixing provided for the embodiments of the present application is stepwise gradient mixing and and paste reaction control schematic diagram; Fig. 3 The smelting optimization schematic diagram of preparation and casting of the grid alloy provided for the embodiments of the present application. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application. EMBODIMENT

[0021] REFERENCE Figs. 1-3 The present application provides a technical solution: a high specific energy lead-carbon battery manufacturing method, the high specific energy lead-carbon battery manufacturing method is as follows: S1, selection and pretreatment of carbon materials, selecting activated carbon, graphene, carbon nanotubes and other carbon materials with high specific surface area; S2, preparation of lead-carbon negative electrode paste, pretreated carbon materials, lead powder, sulfuric acid, short fibers, expanding agent and deionized water are mixed by high-speed stirring to form a uniform lead-carbon paste; S3, preparation and casting of grid alloy, using low-antimony or antimony-free alloys such as lead-calcium-tin-aluminum, after melting in a furnace, through gravity casting or stretching grid process, cast into light grid; S4, coating and curing, placing the coated wet plate in a high-temperature and high-humidity curing room; S5, assembly of the group, interlacing and stacking the positive plate, negative plate and AGM separator after curing and drying, and welding them together through busbars to assemble into a group; S6, battery shell packaging and welding, placing the assembled group into a battery tank, covering the battery cover, ensuring its sealing through heat sealing or epoxy adhesion, and welding the pole to the terminal on the cover; S7, electrolyte filling and internal formation, using a vacuum liquid filling machine to inject precisely measured dilute sulfuric acid concentration (37%-38%) electrolyte (0.1%-0.3% zinc borate is added to the electrolyte as a high-temperature stabilizer to inhibit electrode corrosion in an environment above 60℃) into the battery; S8, performance detection and aging, the battery after formation is detected by open circuit voltage, internal resistance, capacity, large current discharge characteristics, and the qualified products are screened out, then the battery voltage and performance are stabilized by standing aging, finally the battery is cleaned, labeled and packaged.

[0022] In S2, the preparation of the lead-carbon negative electrode paste further comprises step-by-step pretreatment, gradient mixing and process precision control, the step-by-step pretreatment is the pretreatment and activation of the carbon fiber, specifically: S2.1.1, the selected high specific surface area activated carbon or carbon nanomaterial is placed in a dilute nitric acid or dilute sulfuric acid solution (5%-10% nitric acid, 10%-15% sulfuric acid) and stirred at a constant temperature of 60-80 degrees for 2-4 hours; S2.1.2, the carbon material after acid washing is repeatedly washed with a large amount of deionized water until it is neutral, and then is placed in a vacuum drying box and dried at 120 degrees to ensure that there is no water residue; S2.1.3, the pretreated and dried carbon material is mixed with part of the deionized water in the formula and an appropriate amount of dispersant (0.5%-2% of the weight of the carbon material), and high-intensity ultrasonic treatment is performed using an ultrasonic cell disruptor to form a uniform and stable carbon material aqueous dispersion, and the pH of the dispersion is controlled at 6.5-7.5.

[0023] In S2, the gradient mixing is step-by-step gradient mixing and paste reaction control, specifically: S2.2.1, all the required lead powder, short fibers and expanding agent are first put into a double-shaft vacuum and paste machine; S2.2.2, the carbon material dispersion prepared in the first step is mixed with the remaining deionized water and slowly added to the dry mixture being stirred at low speed; S2.2.3, sulfuric acid of a specified concentration is added to the slurry in multiple and slow steps, and the cooling system of the paste machine is started at the same time.

[0024] In S2, the process precision control is vacuum degassing and paste performance regulation, specifically: S2.3.1, after high-speed stirring, the vacuum system of the paste machine is immediately started, and runs at medium-low speed for 5-8 minutes; S2.3.2, a small amount of paste is taken out, and the apparent density of the paste is detected using a paste apparent density meter, and the consistency of the paste is checked by hand or scraper; S2.3.3, the prepared lead-carbon paste is taken out of the paste machine and placed in a sealed container for aging for at least 2 hours before being coated on the plate.

[0025] In S3, the preparation and casting of the grid alloy further comprises smelting optimization, quality detection and surface treatment, and the smelting optimization specifically comprises: S3.1.1, inert gas or special protective salt is introduced above the furnace to form a protective atmosphere, which minimizes the loss of alloying elements due to oxidation; S3.1.2, a closed continuous feeding system is used to automatically add pure lead ingots, master alloys and aluminum wires into the furnace according to the proportion; S3.1.3, an online spectral analyzer is used to detect the composition of the molten alloy at regular intervals, and the feeding ratio is automatically adjusted based on the feedback data.

[0026] Specifically, the quality detection is: S3.2.1, a high-speed camera is installed on the production line to detect the appearance of each cast grid or continuous grid, and automatically identify and remove products with defects such as burrs, cracks and flash; S3.2.2, the finished grid is 100% online weighed and key point laser thickness measured to ensure that its weight and size tolerance meet the strict requirements of lightweight design, and the data is recorded synchronously for traceability.

[0027] Specifically, the surface treatment is: S3.3.1, the grease and dirt on the surface of the grid are removed by an alkaline solution, and then a weak acid solution such as dilute acetic acid or citric acid is used for slight etching to remove the extremely thin oxide layer and expose the fresh metal surface; S3.3.2, the grid is subjected to electrochemical treatment to form a thin and dense PbO2 or specific oxide film on its surface.

[0028] In S2.1.3, the deionized water accounts for one-third of the total weight, the dispersing agent is polyethylene glycol PEG, and the power of ultrasonic treatment is set to 800W with a duration of 30 minutes.

[0029] In S2.2.1, the low-speed stirring speed is 100-200rpm, and the dry mixing time is 5-10 minutes; In S2.2.2, the stirring speed is increased from low speed to medium speed of 300-400rpm, and the wet mixing time is 10-15 minutes.

[0030] In S2.2.3, the addition of sulfuric acid is divided into batches: First batch of sulfuric acid: add a small amount of sulfuric acid, stir at medium speed, and observe the slow rise of the paste temperature to the preset value, control at 40 degrees; Subsequent batches: control the acid addition rate to keep the paste temperature stable between 45-55 degrees; After all the sulfuric acid is added, switch to high-speed stirring at a speed of 500-600rpm for homogenization, with a duration of 3-5 minutes. Example

[0031] M1, first, the carbon material is screened and pretreated, the activated carbon material with high specific surface area is selected, and the activated carbon material is placed in a dilute nitric acid solution, stirred at 70 DEG C for 3 hours; after acid washing, it is repeatedly washed with a large amount of deionized water until it is neutral, then it is completely dried in a vacuum drying oven at 120 DEG C, the dried carbon material is mixed with one third of the total amount of deionized water (conductivity ≤ 5 μS / cm) and an appropriate amount of polyethylene glycol PEG dispersant, and an 800 W ultrasonic cell disrupter is used for treatment for 30 minutes, the particle size distribution detection result (D50 ≤ 100 nm) of the carbon material dispersion liquid after ultrasonic treatment, a uniform and stable carbon material aqueous dispersion liquid is formed; M2, in the preparation of the lead-carbon negative electrode paste, a double-shaft vacuum and paste machine is used, all the lead powder, short fibers and expanding agent are first put in, and dry mixing is carried out at a low speed of 100-200 rpm for 5-10 minutes; then the prepared carbon material dispersion liquid is mixed with the remaining deionized water, slowly added into the dry mixing material, and the stirring speed is increased to 300-400 rpm, wet mixing is carried out for 10-15 minutes, then sulfuric acid with a specified concentration is slowly added in batches: a small amount of sulfuric acid is first added, and the paste temperature is slowly increased to 40 DEG C by medium-speed stirring; the subsequent batches control the acid addition rate to make the temperature stable between 45-55 DEG C, after all the sulfuric acid is added, switch to high-speed stirring at 500-600 rpm for 3-5 minutes for homogenization, then open the vacuum system, and deaerate at medium-low speed for 5-8 minutes, after the paste visual density and consistency are detected to be qualified, the paste is placed in a sealed container for aging for 2 hours; M3, the grid alloy is prepared by using lead-calcium-tin-aluminum antimony-free alloy, inert gas protection is used during smelting, and a closed continuous feeding system is used to automatically add pure lead ingot, master alloy and aluminum wire, the composition is detected in real time by an online spectrum analyzer and the proportion is adjusted, the appearance is detected by a high-speed camera after casting, the defective products are automatically removed, and the grid is 100% online weighed and laser thickness measured, the surface treatment is first oil removal by an alkaline solution, then slight etching by dilute acetic acid, and finally electrochemical treatment to form a dense PbO2 film; M4, the subsequent processes include: the aged lead-carbon paste is coated on the treated grid, and after high temperature and high humidity curing, it is stacked with positive plates and AGM separators to form a group of plates, the busbars are welded, then sealed and welded in a battery shell, precise amount of dilute sulfuric acid electrolyte is injected by a vacuum liquid filling machine, internal formation is carried out, and finally the battery is detected for open circuit voltage, internal resistance, capacity and large current discharge, the qualified products are cleaned, labeled and packaged after standing and aging.

[0032] The innovation of the scheme is: Based on S2.1, the carbon material is pretreated by dilute acid under heating conditions, effectively removing the metal impurities and oxidizing the functional groups on the surface of the carbon material, significantly improving the electrochemical purity and reactivity of the carbon material, using high-intensity ultrasonic treatment combined with a dispersing agent to disperse the easily agglomerated nano-carbon material in the liquid phase, forming a uniform and stable aqueous dispersion, ensuring that the carbon material can be uniformly distributed at the nanoscale in the subsequent lead paste, maximizing its conductivity and capacitance effect, standardizing the pretreatment process to ensure the consistency of the performance of the carbon material between different batches, laying the foundation for the preparation of high-performance and high-consistency negative electrodes. Based on S2.2 and S2.3, the traditional one-time feeding method is changed, and a gradient mixing strategy of dry mixing-wet mixing-batch acid addition is adopted, which ensures the uniform mixing of each component in the high-density lead powder at the micro level, avoids agglomeration, and controls the temperature of the paste mixing process, which is a violent exothermic reaction, in the optimal range of 45-55 DEG C, the first batch of acid triggers the reaction and the temperature rises, the subsequent acid addition rate is controlled to maintain a constant temperature, and finally high-speed homogenization is ensured to ensure that the paste has an ideal crystal structure and pore structure. Based on S3, by covering with inert gas / protection salt and closed continuous automatic feeding system, the burning loss of easily oxidizable elements in low antimony / antimony-free alloy is greatly reduced, the composition of the molten alloy is ensured to be accurate and stable, combined with the real-time feedback and automatic fine adjustment of the online spectrum analyzer, the closed-loop control of the alloy composition is realized, the metallurgical grade precision is achieved, the machine vision automatic detection of appearance defects is introduced, combined with online weighing and laser thickness measurement, the weight and size of each grid are monitored with an error of millimeters, which is not only an innovation in quality control, but also realizes the full traceability of production data, meets the strict tolerance requirements of light weight grid, through chemical treatment of alkali washing + weak acid etching and electrochemical pre-generation of dense oxide film, the grid is thoroughly cleaned and has better surface properties, this layer of film can improve the adhesion between the grid and the active material, inhibit corrosion, and improve the initial performance and life of the battery. The above data shows that the contribution of the negative electrode to the energy density is significantly improved, the durability in long-term high-frequency charge and discharge scenarios is greatly enhanced, the utilization efficiency of raw materials is significantly improved, and the waste of active material is reduced.

[0033] The above description is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can make equivalent replacement or change according to the technical scheme and inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for manufacturing a high-energy-density lead-carbon battery, characterized in that: The method for manufacturing the high-energy-density lead-carbon battery is as follows: S1. Screening and pretreatment of carbon materials, selecting carbon materials with high specific surface area such as activated carbon, graphene, and carbon nanotubes. S2. Preparation of lead-carbon negative electrode paste: Pretreated carbon material is mixed with lead powder, sulfuric acid, short fiber, expansion agent and deionized water, and stirred at high speed to form a uniform lead-carbon paste. S3. Preparation and casting of grid alloy: Low-antimony or antimony-free alloys such as lead, calcium, tin, and aluminum are used. After melting in a furnace, lightweight grids are cast by gravity casting or stretch grid process. S4. Coating and curing: Place the coated wet electrode plate into a high-temperature and high-humidity curing chamber. S5. Electrode group assembly: After curing and drying, the positive electrode plate, negative electrode plate and AGM separator are stacked alternately and welded together by busbar to assemble the electrode group. S6. Battery casing encapsulation and welding: Place the assembled electrode group into the battery case, cover the battery cover, ensure its sealing by heat sealing or epoxy adhesive, and weld the electrode post to the terminal on the cover. S7. Electrolyte filling and internal formation: The precisely metered dilute sulfuric acid electrolyte is injected into the battery through a vacuum liquid filling machine; S8. Performance testing and aging: After formation, the open-circuit voltage, internal resistance, capacity, and high-current discharge characteristics of the battery are tested. After screening out qualified products, the battery is left to age in place to stabilize the battery voltage and performance. Finally, the battery is cleaned, labeled, and packaged.

2. The method for manufacturing a high-energy-density lead-carbon battery according to claim 1, characterized in that: The preparation of the lead-carbon negative electrode paste in S2 also includes stepwise pretreatment, gradient mixing, and precise process control. The stepwise pretreatment is the pretreatment and activation of carbon fibers, specifically: S2.1.1 Place the selected high specific surface area activated carbon or carbon nanomaterials in a dilute nitric acid or dilute sulfuric acid solution and stir at a constant temperature of 60-80 degrees for 2-4 hours. S2.1.2 Rinse the acid-washed carbon material repeatedly with plenty of deionized water until neutral, then place it in a vacuum drying oven at 120 degrees Celsius to dry it thoroughly, ensuring no moisture residue remains; S2.1.

3. The pretreated dried carbon material is mixed with a portion of the deionized water and an appropriate amount of dispersant in the formula, and then subjected to high-intensity ultrasonic treatment using an ultrasonic cell disruptor to form a uniform and stable aqueous dispersion of carbon material.

3. The method for manufacturing a high-energy-density lead-carbon battery according to claim 2, characterized in that: The gradient mixing is a stepwise gradient mixing and paste reaction control, specifically: S2.2.1 In the twin-shaft vacuum paste machine, first add all the required lead powder, short fibers and expanding agent; S2.2.

2. Mix the carbon material dispersion prepared in the first step with the remaining deionized water and slowly add it to the dry mixture that is being stirred at low speed. S2.2.

3. Add sulfuric acid of the specified concentration to the slurry slowly in multiple portions, while simultaneously starting the cooling system of the paste-making machine.

4. The method for manufacturing a high-energy-density lead-carbon battery according to claim 3, characterized in that: The process is precisely controlled through vacuum degassing and ointment performance regulation, specifically as follows: S2.3.1 After the high-speed mixing is completed, immediately turn on the vacuum system of the paste mixer and run it at medium-low speed for 5-8 minutes; S2.3.2 Take out a small amount of ointment, use an ointment densitometer to test its apparent density, and at the same time check the consistency of the ointment by hand or with a scraper; S2.3.

3. Take the prepared lead-carbon paste out of the paste mixing machine and place it in a sealed container to mature for at least 2 hours before coating the plate.

5. The method for manufacturing a high-energy-density lead-carbon battery according to claim 4, characterized in that: The preparation and casting of the grid alloy in S3 also includes smelting optimization, quality inspection, and surface treatment. Smelting optimization specifically includes: S3.1.

1. Inert gas is introduced above the furnace or a special protective salt is applied to create a protective atmosphere and minimize the oxidation loss of alloying elements. S3.1.

2. A closed continuous feeding system is adopted to automatically add pure lead ingots, master alloys and aluminum wires into the furnace in proportion. S3.1.3 Use an online spectrometer to periodically detect the composition of the molten alloy and automatically fine-tune the feeding ratio based on the feedback data.

6. The method for manufacturing a high-energy-density lead-carbon battery according to claim 5, characterized in that: The quality inspection specifically includes: S3.2.1 Install high-speed cameras on the production line to perform visual inspection on each cast grid or continuous grid, automatically identify and reject products with defects such as burrs, cracks, and flash. S3.2.

2. Perform 100% online weighing and key point laser thickness measurement on the finished grid panels to ensure that their weight and dimensional tolerances meet the strict requirements of lightweight design. The data is recorded synchronously for traceability.

7. A method for manufacturing a high-energy-density lead-carbon battery according to claim 6, characterized in that: The surface treatment specifically includes: S3.3.1 Remove grease and dirt from the grid surface with an alkaline solution, and then lightly etch with a weak acid solution such as dilute acetic acid or citric acid to remove the very thin oxide layer and expose the fresh metal surface. S3.3.

2. Electrochemical treatment is performed on the grid to pre-generate an extremely thin and dense PbO2 or specific oxide film on its surface.

8. The method for manufacturing a high-energy-density lead-carbon battery according to claim 7, characterized in that: In S2.1.3, deionized water accounts for one-third of the total weight, polyethylene glycol (PEG) is used as the dispersant, and the ultrasonic treatment power is set to 800W for 30 minutes.

9. A method for manufacturing a high-energy-density lead-carbon battery according to claim 8, characterized in that: The low-speed stirring speed in S2.2.1 is 100-200 rpm, and the dry mixing time is 5-10 minutes; In S2.2.2, the stirring speed should be increased from low to medium (300-400 rpm) for 10-15 minutes for wet mixing.

10. A method for manufacturing a high-energy-density lead-carbon battery according to claim 9, characterized in that: The sulfuric acid added in S2.2.3 is further subdivided into batches as follows: First batch of sulfuric acid: Add a small amount of sulfuric acid, stir at medium speed, and observe the temperature of the paste slowly rise to the preset value, which should be controlled at 40 degrees Celsius. Subsequent batches: Control the acid addition rate to keep the paste temperature stable between 45-55 degrees Celsius; After all the sulfuric acid has been added, switch to high-speed stirring at 500-600 rpm to homogenize for 3-5 minutes.

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