Composition for positive electrode lead paste, positive electrode lead paste and preparation method and application of positive electrode lead paste

Abstract

The invention provides a composition for positive electrode lead paste, the positive electrode lead paste and a preparation method and application of the positive electrode lead paste, and particularly relates to the technical field of battery energy storage. The composition for the positive lead paste is prepared from the following components in parts by weight: 0.02 to 0.04 part of binder, 0.1 to 0.3 part of pore forming agent, 0.01 to 0.03 part of first conductive agent and 0.2 to 0.3 part of second conductive agent, wherein the first conductive agent is a linear conductive agent; and the second conductive agent is a sheet-shaped conductive agent. The composition for the positive electrode lead paste significantly improves the cycle life and the charge-discharge performance of the battery. According to the composition, through the synergistic effect of all the components, the energy density is improved, meanwhile, the long cycle stability is considered, and the technical problem that the utilization rate and the cycle life of active substances in a traditional lead-acid battery are difficult to consider at the same time is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery energy storage, in particular to a positive lead paste composition, a positive lead paste and a preparation method and application thereof. BACKGROUND

[0002] Owing to the advantages of low cost, high safety and mature technology, lead-acid batteries have long dominated the two-wheeled electric vehicle battery market and are the battery type with the highest application proportion in the industry.

[0003] In the two-wheeled electric vehicle manufacturing process, alloy materials are widely used to replace traditional plastic parts, which increases the proportion of the overall vehicle structure weight, indirectly compressing the redundant space for increasing the weight of the battery, which limits the traditional path of simply increasing the weight of the battery to improve the capacity, and thus puts forward higher requirements for the energy density of lead-acid batteries.

[0004] In the performance improvement research of lead-acid batteries, the further improvement of energy density faces key technical bottlenecks: the utilization rate of positive active material is a core factor affecting the energy density of the battery, and in the existing technology, if the utilization rate of the positive active material is improved by conventional means, the cycle life of the battery will be significantly reduced, and there is a technical contradiction between the two that is difficult to balance.

[0005] Therefore, the present application is proposed. SUMMARY

[0006] The present application aims to provide a positive lead paste composition, a positive lead paste and a preparation method and application thereof, to solve at least one of the above technical problems.

[0007] To solve the above technical problems, the present application adopts the following technical solutions: The first aspect of the present application provides a positive lead paste composition, which comprises, in terms of weight fraction, 0.02-0.04 parts of a binder, 0.1-0.3 parts of a pore former, 0.01-0.03 parts of a first conductive agent and 0.2-0.3 parts of a second conductive agent; wherein the first conductive agent is a linear conductive agent; and the second conductive agent is a sheet-shaped conductive agent.

[0008] Further, the binder comprises at least one of carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), hydroxyethyl cellulose (HEC) and polyethylene oxide (PEO).

[0009] Preferably, the pore former comprises at least one of fumed silica, hollow glass microbeads, hollow silica microspheres, zeolite molecular sieves and mesoporous silica.

[0010] Further, the linear conductive agent comprises at least one of carbon fibers and carbon nanotubes.

[0011] Preferably, the sheet-like conductive agent comprises graphene.

[0012] Furthermore, the positive electrode lead paste composition comprises, by weight, 0.02-0.04 parts of carboxymethyl cellulose, 0.1-0.3 parts of fumed silica, 0.01-0.03 parts of carbon fiber, and 0.2-0.3 parts of graphene.

[0013] A second aspect of the present invention provides a positive electrode lead paste, comprising a lead paste base formulation and the positive electrode lead paste composition described in the first aspect; wherein the positive electrode lead paste composition is added to the positive electrode lead paste in an amount of 0.7 to 1.0 wt%.

[0014] Furthermore, the amount of the positive electrode lead paste composition added to the positive electrode lead paste is 0.8~0.9wt%.

[0015] Furthermore, the basic formula of the lead paste, by weight, includes 100 parts lead powder, 8-10 parts sulfuric acid, 10-12 parts pure water, 0.09-0.15 parts short fiber, 0.1-0.12 parts antimony trioxide, and 0.15-0.3 parts stannous sulfate.

[0016] The third aspect of the present invention provides a method for preparing the positive electrode lead paste, wherein the raw materials in the lead paste base formula and the positive electrode lead paste are mixed evenly with the composition, and the paste is extracted at a temperature below 45°C to obtain the positive electrode lead paste.

[0017] In one embodiment of the present invention, a portion of lead powder, a positive electrode lead paste composition, short fibers, antimony trioxide, and stannous sulfate are added to a paste mixing machine and mixed evenly. Then, the remaining lead powder is added and stirred for 8-10 minutes. Next, pure water is added and mixed for 4-5 minutes. Finally, sulfuric acid is added within 12-15 minutes. After the lead paste temperature rises above 73°C, the temperature is lowered and the paste is discharged at a temperature below 45°C to obtain the positive electrode lead paste.

[0018] The fourth aspect of this invention provides the application of the aforementioned positive electrode paste in lead-acid batteries or lead-carbon batteries.

[0019] Compared with the prior art, the present invention has at least the following beneficial effects: The positive electrode lead paste composition provided by this invention introduces a pore-forming agent to construct a porous structure in the positive electrode lead paste, effectively increasing the contact area between the active material and the electrolyte, and significantly improving the utilization rate of the positive electrode active material. Simultaneously, the use of a first conductive agent and a second conductive agent forms a three-dimensional synergistic conductive network, which not only compensates for the poor conductivity of the pore-forming agent but also significantly improves the electronic conduction capacity within the lead paste, reducing the battery's internal resistance. Combined with the use of a binder, the structural stability of the lead paste is enhanced, effectively suppressing the softening and shedding of the positive electrode material during charging and discharging, thereby significantly improving the battery's cycle life and charge-discharge performance. Through the synergistic effect of its components, this composition improves energy density while maintaining long-term cycle stability, solving the technical challenge of balancing active material utilization and cycle life in traditional lead-acid batteries.

[0020] The positive electrode paste provided by the present invention, in view of the advantages of the above-mentioned positive electrode paste composition, achieves synergistic optimization of high energy density and long cycle life without increasing battery weight.

[0021] The preparation method provided by this invention is simple in process, can handle large batch sizes, and is suitable for large-scale industrial production.

[0022] The positive electrode lead paste provided by this invention, given its advantages, has good prospects for industrial application in lead-acid batteries and lead-carbon batteries. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 The lifetime curves obtained from testing sample 1 in Example 6, Comparative Example 17, and Example 6′ are shown. Figure 2 This is a SEM image of the positive plate prepared in Example 6 after the cycling process is completed; Figure 3 This is a SEM image of the positive plate prepared in Comparative Example 17 after the cycling process. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown herein can generally be arranged and designed in various different configurations.

[0026] The first aspect of the present invention provides a composition for positive electrode lead paste, comprising, by weight, 0.02 to 0.04 parts of binder, 0.1 to 0.3 parts of pore-forming agent, 0.01 to 0.03 parts of first conductive agent and 0.2 to 0.3 parts of second conductive agent; wherein the first conductive agent is a linear conductive agent and the second conductive agent is a sheet-like conductive agent.

[0027] The positive electrode lead paste composition provided by this invention introduces a pore-forming agent to construct a porous structure in the positive electrode lead paste, effectively increasing the contact area between the active material and the electrolyte, and significantly improving the utilization rate of the positive electrode active material. Simultaneously, the use of a first conductive agent and a second conductive agent forms a three-dimensional synergistic conductive network, which not only compensates for the poor conductivity of the pore-forming agent but also significantly improves the electronic conduction capacity within the lead paste, reducing the battery's internal resistance. Combined with the use of a binder, the structural stability of the lead paste is enhanced, effectively suppressing the softening and shedding of the positive electrode material during charging and discharging, thereby significantly improving the battery's cycle life and charge-discharge performance. Through the synergistic effect of its components, this composition improves energy density while maintaining long-term cycle stability, solving the technical challenge of balancing active material utilization and cycle life in traditional lead-acid batteries.

[0028] Typical, but not limiting, the positive electrode lead paste composition comprises, by weight, 0.02 parts, 0.03 parts, or 0.04 parts of binder, or any value in the range of 0.02 to 0.04 parts; 0.1 parts, 0.2 parts, or 0.3 parts of pore-forming agent, or any value in the range of 0.1 to 0.3 parts; 0.01 parts, 0.02 parts, or 0.03 parts of first conductive agent, or any value in the range of 0.01 to 0.03 parts; and 0.2 parts, 0.25 parts, or 0.3 parts of second conductive agent, or any value in the range of 0.2 to 0.3 parts.

[0029] Furthermore, the adhesive comprises at least one of carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), hydroxyethyl cellulose (HEC), and polyethylene oxide (PEO).

[0030] Preferably, the pore-forming agent includes at least one of fumed silica, glass microspheres, hollow silica microspheres, zeolite molecular sieves, and mesoporous silica.

[0031] Furthermore, the linear conductive agent includes at least one of carbon fiber and carbon nanotubes.

[0032] Preferably, the sheet-like conductive agent comprises graphene.

[0033] Furthermore, the positive electrode lead paste composition comprises, by weight, 0.02-0.04 parts of carboxymethyl cellulose, 0.1-0.3 parts of fumed silica, 0.01-0.03 parts of carbon fiber, and 0.2-0.3 parts of graphene.

[0034] Typical, but not limiting, the positive electrode lead paste composition comprises, by weight, 0.02 parts, 0.03 parts, or 0.04 parts of carboxymethyl cellulose, or any value in the range of 0.02 to 0.04 parts; 0.1 parts, 0.2 parts, or 0.3 parts of fumed silica, or any value in the range of 0.1 to 0.3 parts; 0.01 parts, 0.02 parts, or 0.03 parts of carbon fiber, or any value in the range of 0.01 to 0.03 parts; and 0.2 parts, 0.25 parts, or 0.3 parts of graphene, or any value in the range of 0.2 to 0.3 parts.

[0035] A second aspect of the present invention provides a positive electrode lead paste, comprising a lead paste base formulation and the positive electrode lead paste composition described in the first aspect; wherein the positive electrode lead paste composition is added to the positive electrode lead paste in an amount of 0.5 to 1.0 wt%.

[0036] The positive electrode paste provided by the present invention, in view of the advantages of the above-mentioned positive electrode paste composition, achieves synergistic optimization of high energy density and long cycle life without increasing battery weight.

[0037] By controlling the above-mentioned addition amount within the range of 0.7~1.0wt%, a good balance between process stability and economy can be achieved while ensuring a significant improvement in battery performance. This addition amount is sufficient to allow the binder, pore-forming agent, and dual-conductive agent (linear and sheet-like) in the composition to fully exert their synergistic effects. Within this dosage range, the synergistic optimization of high energy density and long cycle life can be fully realized without excessive addition leading to excessive viscosity, dispersion difficulties, or significant increases in cost during the paste-making process.

[0038] The amount of the composition for positive electrode lead paste added to the positive electrode lead paste is typically, but not limitingly, for example, 0.7 wt%, 0.8 wt%, 0.9 wt%, or 1.0 wt%, or any value in the range of 0.7 to 1.0 wt%.

[0039] Furthermore, the amount of the positive electrode lead paste composition added to the positive electrode lead paste is 0.8~0.9wt%.

[0040] The amount of the composition for positive electrode lead paste added to the positive electrode lead paste is typically, but not limitingly, for example, 0.8 wt%, 0.85 wt%, or 0.9 wt%, or any value in the range of 0.8 to 0.9 wt%.

[0041] Furthermore, the basic formula of the lead paste, by weight, includes 100 parts lead powder, 8-10 parts sulfuric acid, 10-12 parts pure water, 0.09-0.15 parts short fiber, 0.1-0.12 parts antimony trioxide, and 0.15-0.3 parts stannous sulfate.

[0042] The lead paste base formula, by weight, typically but not limited to, includes 100 parts lead powder; 8, 9, or 10 parts sulfuric acid, or any value within the range of 8 to 10 parts; 10, 11, or 12 parts pure water, or any value within the range of 10 to 12 parts; 0.09, 0.10, 0.12, 0.14, or 0.15 parts short fiber, or any value within the range of 0.09 to 0.15 parts; 0.1, 0.11, or 0.12 parts antimony trioxide, or any value within the range of 0.1 to 0.12 parts; and 0.15, 0.2, 0.25, or 0.3 parts stannous sulfate, or any value within the range of 0.15 to 0.3 parts.

[0043] The third aspect of the present invention provides a method for preparing the positive electrode lead paste, wherein the raw materials in the lead paste base formula and the positive electrode lead paste are mixed evenly with the composition, and the paste is extracted at a temperature below 45°C to obtain the positive electrode lead paste.

[0044] The preparation method provided by this invention is simple in process, can handle large batch sizes, and is suitable for large-scale industrial production.

[0045] In one embodiment of the present invention, a portion of lead powder, a positive electrode lead paste composition, short fibers, antimony trioxide, and stannous sulfate are added to a paste mixing machine and mixed evenly. Then, the remaining lead powder is added and stirred for 8-10 minutes. Next, pure water is added and mixed for 4-5 minutes. Finally, sulfuric acid is added within 12-15 minutes. After the lead paste temperature rises above 73°C, the temperature is lowered and the paste is discharged at a temperature below 45°C to obtain the positive electrode lead paste.

[0046] In one embodiment of the present invention, a portion of lead powder, the above-mentioned positive electrode lead paste composition, short fibers, antimony trioxide, and stannous sulfate are added to a paste mixer and mixed evenly. Then, the remaining lead powder is added and stirred. The stirring time is typically, but not limitingly, 8 min, 9 min, or 10 min, or any value within the range of 8 to 10 min. Next, pure water is added and mixed. The mixing time is typically, but not limitingly, 4 min or 5 min, or any value within the range of 4 to 5 min. Finally, sulfuric acid is added within 12 min, 13 min, 14 min, or 15 min. After the lead paste temperature rises above 73°C, the temperature is lowered and the paste is discharged at a temperature below 45°C (typically, but not limitingly, 30°C, 35°C, 40°C, or 44°C, etc.) to obtain the positive electrode lead paste.

[0047] The fourth aspect of the present invention provides the application of the aforementioned positive electrode paste in lead-acid batteries or lead-carbon batteries.

[0048] The positive electrode lead paste provided by this invention, given its advantages, has good prospects for industrial application in lead-acid batteries and lead-carbon batteries.

[0049] The following detailed description of some embodiments of the present invention is provided in conjunction with examples. Unless otherwise specified, the following embodiments and features can be combined with each other. Unless otherwise specified, the raw materials used in the present invention are commercially available.

[0050] Example 1 This embodiment provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of carboxymethyl cellulose, 0.2 kg of fumed silica, 0.02 kg of carbon fiber, and 0.25 kg of graphene.

[0051] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0052] Example 2 This embodiment provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of polyvinyl alcohol, 0.2 kg of mesoporous silica, 0.02 kg of carbon nanotubes, and 0.25 kg of graphene.

[0053] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0054] Example 3 This embodiment provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of hydroxyethyl cellulose, 0.2 kg of hollow silica microspheres, 0.02 kg of carbon fiber, and 0.25 kg of graphene.

[0055] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0056] Example 4 This embodiment provides a composition for positive electrode lead paste, specifically comprising 0.02 kg of carboxymethyl cellulose, 0.3 kg of fumed silica, 0.01 kg of carbon fiber, and 0.3 kg of graphene.

[0057] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0058] Example 5 This embodiment provides a composition for positive electrode lead paste, specifically comprising 0.04 kg of carboxymethyl cellulose, 0.1 kg of fumed silica, 0.03 kg of carbon fiber, and 0.2 kg of graphene.

[0059] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0060] Comparative Example 1 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.2 kg of fumed silica, 0.02 kg of carbon fiber, and 0.25 kg of graphene.

[0061] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0062] Comparative Example 2 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of carboxymethyl cellulose, 0.02 kg of carbon fiber, and 0.25 kg of graphene.

[0063] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0064] Comparative Example 3 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of carboxymethyl cellulose, 0.2 kg of fumed silica, and 0.25 kg of graphene.

[0065] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0066] Comparative Example 4 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of carboxymethyl cellulose, 0.2 kg of fumed silica, and 0.02 kg of carbon fiber.

[0067] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0068] Comparative Example 5 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.02 kg of carbon fiber and 0.25 kg of graphene.

[0069] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0070] Comparative Example 6 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of carboxymethyl cellulose and 0.25 kg of graphene.

[0071] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0072] Comparative Example 7 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.03 kg of carboxymethyl cellulose and 0.2 kg of fumed silica.

[0073] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0074] Comparative Example 8 This comparative example provides a composition for positive electrode lead paste, specifically comprising 0.2 kg of fumed silica and 0.02 kg of carbon fiber.

[0075] The above raw materials are mixed evenly to obtain the composition for positive electrode lead paste.

[0076] Examples 6-10 These embodiments provide a positive electrode lead paste, specifically comprising 100 kg of lead powder and 9 kg of sulfuric acid (density 1.4 g / cm³). 2 The following ingredients were used: 10 kg of pure water, 0.12 kg of short fibers, 0.12 kg of antimony trioxide, 0.15 kg of stannous sulfate, and 1 kg of the corresponding positive electrode lead paste composition provided in Examples 1-5 (apparent density 4.5 ± 0.03 g / cm³). 3 ).

[0077] The preparation methods for these embodiments are as follows: 1. First, add half of the lead powder to the paste mixer, then add the positive electrode lead paste composition, short fibers, antimony trioxide, and stannous sulfate. Finally, add the remaining half of the lead powder to the paste mixer and stir for 8-10 minutes.

[0078] 2. Add pure water to the paste mixer and stir for 4-5 minutes.

[0079] 3. Add sulfuric acid to the paste mixing machine. The acid addition time is 12-15 minutes. When the temperature of the lead paste reaches above 73℃, start the cooling process. After adding the acid, stir for 4-6 minutes to obtain the positive electrode lead paste. (The temperature of the paste should not exceed 45℃ when it is discharged).

[0080] Comparative Examples 9-16 These comparative examples provide a positive electrode lead paste, which differs from Example 6 in that the composition of the positive electrode lead paste used is provided by Comparative Examples 1 to 8, while the other raw materials and preparation methods are the same as those in Example 6, and will not be repeated here.

[0081] Comparative Example 17 This comparative example provides a positive electrode lead paste, which differs from Example 6 in that the positive electrode lead paste composition is not used in this example. The other raw materials and preparation methods are the same as in Example 6, and will not be repeated here.

[0082] Test Example 1 The positive electrode plates obtained from the examples and comparative examples were coated, cured, and dried to obtain positive electrode plates. These plates were then applied to lead-acid batteries (model 6-DZF-22 of the same specification).

[0083] The above-mentioned batteries were used for capacity and lifespan testing. Capacity was measured by discharging at 0.5C to 10.5V per cell; lifespan was measured by discharging at 1C to 10.5V per cell and cycling. The measured capacity was divided by 0.91 to convert to a 2-hour capacity. If the converted capacity was below 80%, the lifespan was considered terminated. During the implementation process, each embodiment and comparative example was assembled with three batteries for measurement, and the best performance was recorded in Table 1.

[0084] Table 1

[0085] As shown in Table 1, Examples 6-10, while maintaining a relatively constant battery weight, all achieved high capacities of 22.4-22.7 Ah and long cycle lives of 342-368 cycles, significantly outperforming all comparative examples. Comparative Examples 9 and 16, lacking a binder, suffered structural instability and a significant decrease in lifespan; Comparative Example 10, lacking a pore-forming agent, limited the utilization rate of active materials, causing capacity decay; Comparative Examples 11, 12, 13, and 15, lacking either linear or sheet-like conductive agents individually, all disrupted the three-dimensional synergistic conductive network, affecting electron conduction efficiency and reducing capacity; while Comparative Example 17, completely lacking the composition of this invention, exhibited the worst performance. It is evident that only when binders, pore-forming agents, linear conductive agents, and sheet-like conductive agents coexist and work synergistically can the porous structure and electron transport capacity of the positive electrode lead paste be improved while simultaneously enhancing its mechanical stability. This overcomes the technical bottleneck of balancing energy density and cycle life in traditional lead-acid batteries, achieving synergistic optimization of both.

[0086] Test Example 2 The positive electrode lead paste obtained in Example 6 was used to assemble a 6-DZF-22 battery with a higher design weight, which was recorded as Example 6′. The test was carried out in the same way as in Test Example 1, and the results were recorded in Table 2.

[0087] Table 2

[0088] The test results, as shown in Table 2, indicate that the lead-acid battery using the positive electrode lead paste prepared in this application achieves an energy density increase of over 5% while maintaining a lifespan without significant degradation.

[0089] Data from the testing process of sample 1 in Example 6, Comparative Example 17, and Example 6′ were recorded. Figure 1 The lifespan curve.

[0090] from Figure 1 As can be seen, compared with Comparative Example 17, the battery of Example 6 using the positive electrode lead paste composition of the present invention not only has a higher initial capacity, but also a significantly slower capacity decay rate, exhibiting excellent cycle stability. Crucially, even with a design that increases battery weight to improve capacity (Example 6'), its cycle life still far exceeds that of the standard weight control group (Comparative Example 17), and is comparable to the performance of the standard weight battery of the present invention (Example 6). This strongly demonstrates that the performance improvement brought about by the composition of the present invention is not a simple weight-increasing effect, but rather, through the synergistic effect of constructing a porous structure and a three-dimensional conductive network, it effectively improves the utilization rate of active materials and energy density without sacrificing cycle life, thereby achieving synergistic optimization of high energy density and long cycle life, solving the common technical problem that traditional lead-acid batteries struggle to achieve simultaneously.

[0091] The SEM image of the positive plate after 282 cycles of dissection of Sample 2 from Example 6 is shown below. Figure 2 As shown, the SEM image of the front plate of sample 2 in Comparative Example 17 after 279 cycles of dissection is as follows. Figure 3 As shown.

[0092] from Figure 2 It can be seen that the particle structure of the positive electrode active material on the positive plate remains relatively intact and dense, with uniform pore distribution and no large-area cracks, loosening, or peeling. This indicates that the mechanical strength and pore structure stability of the positive electrode lead paste have been significantly improved through pore-forming agents and the reinforcing effect of binders. Simultaneously, supported by the three-dimensional synergistic conductive network formed by the binder, linear conductive agent, and sheet conductive agent, the mechanical strength and structural stability of the positive electrode lead paste have been further enhanced. This conductive network not only effectively conducts electrons and reduces internal resistance but also acts as a "skeleton," suppressing material pulverization and softening caused by repeated changes in Pb / PbO2 volume during charging and discharging, thereby maintaining the integrity of the electrode. This is the key microscopic basis for achieving a long cycle life.

[0093] from Figure 3It can be seen that the positive electrode active material exhibits significant structural damage, manifested as surface cracking, weakened interparticle bonding, and loosening and shedding of the active material. This degradation is due to the lack of an effective pore-forming structure and a highly efficient conductive network. On the other hand, the stress generated by repeated charging and discharging cannot be effectively buffered, ultimately leading to electrode material fatigue, cracking, and pore collapse, resulting in irreversible capacity loss. Figure 3 This intuitively reveals the root cause of the limited cycle life of traditional lead-acid batteries—structural failure of the positive electrode—and highlights the technological advancement of this invention by introducing a specific composition to solve this core problem.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A composition for positive electrode lead paste, characterized in that, Based on parts by weight, it includes 0.02 to 0.04 parts of adhesive, 0.1 to 0.3 parts of pore-forming agent, 0.01 to 0.03 parts of first conductive agent, and 0.2 to 0.3 parts of second conductive agent; Wherein, the first conductive agent is a linear conductive agent; the second conductive agent is a sheet-like conductive agent.

2. The composition for positive electrode lead paste according to claim 1, characterized in that, The adhesive includes at least one of carboxymethyl cellulose, polyvinyl alcohol, hydroxyethyl cellulose, and polyethylene oxide; Preferably, the pore-forming agent includes at least one of fumed silica, hollow glass microspheres, hollow silica microspheres, zeolite molecular sieves, and mesoporous silica.

3. The composition for positive electrode lead paste according to claim 1, characterized in that, The linear conductive agent includes at least one of carbon fiber and carbon nanotubes; Preferably, the sheet-like conductive agent comprises graphene.

4. The composition for positive electrode lead paste according to any one of claims 1 to 3, characterized in that, Based on parts by weight, it includes 0.02 to 0.04 parts of carboxymethyl cellulose, 0.1 to 0.3 parts of fumed silica, 0.01 to 0.03 parts of carbon fiber, and 0.2 to 0.3 parts of graphene.

5. A positive electrode lead paste, characterized in that, Includes a basic formulation of lead paste and a composition for positive electrode lead paste as described in any one of claims 1 to 4; The amount of the positive electrode lead paste composition added to the positive electrode lead paste is 0.7~1.0 wt%.

6. The positive electrode lead paste according to claim 5, characterized in that, The amount of the composition for positive electrode lead paste added to the positive electrode lead paste is 0.8~0.9wt%.

7. The positive electrode lead paste according to claim 5, characterized in that, The basic formula of the lead paste, by weight, includes 100 parts lead powder, 8-10 parts sulfuric acid, 10-12 parts pure water, 0.09-0.15 parts short fiber, 0.1-0.12 parts antimony trioxide, and 0.15-0.3 parts stannous sulfate.

8. A method for preparing the positive electrode lead paste according to any one of claims 5 to 7, characterized in that, The raw materials in the lead paste base formula and the positive electrode lead paste are mixed evenly, and the paste is extracted at a temperature below 45°C to obtain the positive electrode lead paste.

9. The preparation method according to claim 8, characterized in that, Add some lead powder, positive electrode lead paste composition, short fiber, antimony trioxide, and stannous sulfate to the paste mixer and mix evenly. Then add the remaining lead powder and stir for 8-10 minutes. Next, add pure water and mix for 4-5 minutes. Finally, add sulfuric acid within 12-15 minutes. When the lead paste temperature rises above 73°C, start cooling down and discharge the paste at a temperature below 45°C to obtain the positive electrode lead paste.

10. The application of the positive electrode paste according to any one of claims 5 to 7 in a lead-acid battery or a lead-carbon battery.

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