DESC:
Field of Invention
The present invention relates to a lead antimony alloy composition for use in the manufacture of lead-acid battery grids. It also relates to a continuous Lead Antimony alloy grid production method by casting, rolling and punching.

Background
Traditional methods for producing lead-acid battery grids, especially those utilizing gravity casting, are hindered by drawbacks such as low levels of automation, high labor intensity, and inefficiencies. The field of lead-acid battery grid production often encounters limitations, as evidenced by prior art:

US11522190B2 describes a lead-based alloy containing bismuth, antimony, arsenic, and tin as alloying additions. This alloy is used in the production of doped lead oxides, lead-acid battery active materials, electrodes, and batteries.

US5352549A discloses a co-doped lead oxide for manufacturing storage battery plates, designed to enhance the efficiency of lead-acid batteries. The lead oxide is doped with copper in amounts ranging from 0.01% to 0.1%, along with either tin (0.008% to 0.1%) or antimony (0.005% to 0.08%), based on the total weight of the lead oxide.

CN103050710A outlines a method for preparing lead-antimony alloy grids for lead-acid cells. The process involves melting pure lead and adding pure gadolinium to form a lead-gadolinium master alloy, followed by the addition of pure yttrium to form a lead-yttrium master alloy. Pure antimony is added to the molten lead, which is then heated to 800-900°C for 20-30 minutes, further heated to 1,200-1,300°C for 20-30 minutes, and finally cooled to 600-700°C under nitrogen protection for 30-40 minutes. The lead-gadolinium and lead-yttrium master alloys are then blended into the molten lead-antimony liquid, maintaining the temperature for 1-2 hours to form lead-antimony-gadolinium-yttrium alloy grids.

CN213483776U discloses a lead-antimony alloy grid for a battery, featuring a busbar with an internal fixed block. The lower end of the fixed block connects to a fixed connecting pipe, which extends to a connecting rib. The main grid structure is attached to the lower end of the connecting rib. One end of the grid's main body is equipped with positive and negative plates, while the busbar's outer surface features a solid fixed sleeving. The upper end of the solid fixed sleeving includes an utmost point ear, and the lower end of the grid's main body is provided with a base connecting pipe.

US8404382B2 provides positive active material pastes for flooded deep discharge lead-acid batteries, along with methods for making the same and the batteries themselves.

CN111525195B describes a maintenance-free lead-acid accumulator with excellent deep cycle life and its production method. The positive pole lead plaster comprises 0.05-0.12% short fibers, 0.05-0.3% antimony trioxide additive, 0.4-1.5% 4BS seeds, 8-14% pure water, 8-12% sulfuric acid solution, and the balance of lead powder.

The aforementioned prior art does not address the challenges encountered during the rolling and subsequent punching processes in lead-acid battery grid manufacturing. Traditional methods, particularly gravity casting, are limited by low automation, high labor intensity, and inefficiencies.

The present invention seeks to overcome these challenges by developing a specialized lead-antimony alloy composition, specifically designed to enhance the grid production process, with a focus on antimonial lead alloy grids. Additionally, the invention leverages the inherent advantages of antimonial lead, particularly in enhancing the depth of discharge capability.

Objects of the invention
An object of the present invention is to overcome the challenges of the prior arts.

Another object of the present invention is to provide a meticulously formulated lead antimony alloy composition.

Yet another object of the present invention is to enable a continuous grid production method that significantly reduces manual labor.

Yet another object of the present invention is to address the challenges posed during rolling and subsequently during the process of punching.

Yet another object of the present invention is to achieve a continuous grid production process that not only streamlines manufacturing but also enhances the depth of discharge capability in lead-acid batteries.

Yet another object of the present invention is to improve the overall performance of the lead-acid battery grid, specifically in terms of achieving higher depth of discharge.
These and other advantages of the present invention will become readily apparent from the following detailed description read in conjunction with the accompanying drawings.

Summary
According to one aspect of the present invention it is provided a lead antimony alloy composition for use in manufacturing lead-acid battery grids, comprising lead, tin, antimony, arsenic, selenium, and copper.

Yet another aspect of the present invention is to provide a method for producing lead-acid battery grids, comprising the steps of providing a lead antimony alloy composition comprising lead, tin, antimony, arsenic, selenium, and copper; casting the alloy composition to form a raw strip; rolling the cast strip to reduce thickness; and punching the rolled strip to form battery grids, wherein the method is configured to enhance the performance characteristics of the lead-acid battery grids.

Brief description of drawings
FIG. 1 is a block diagram illustrating the continuous production process of lead-antimony alloy grids, including casting, rolling, and coiling stages.

FIG. 2 is a schematic block diagram illustrating the continuous grid production process involving the rolling, punching, and coiling stages.

Detailed description
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known structure and method are omitted for clarity and conciseness.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

It should be emphasized that the term “comprises/comprising” if used in this specification is taken to specify the presence of stated features, integers, steps or component but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

The present invention provides a lead antimony alloy composition, specifically designed to address the challenges posed during rolling and subsequently during the process of punching. While antimonial lead does not improve mechanical properties after rolling, the present inventors have optimized the alloy for enhanced casting of low thickness raw strip (lower than 7mm), rolling with reduced number of stages (lower than 5 stages) and then in punching. Said method enables a continuous grid production method that significantly reduces manual labor.

In one embodiment, the lead antimony alloy composition is tailored to include varying proportions of tin, antimony, arsenic, selenium, and copper, allowing for customization based on specific performance requirements of the lead-acid battery grids.

The lead antimony alloy composition described in claim 1 is specifically formulated to enhance the manufacturing process of lead-acid battery grids. By incorporating elements such as tin, antimony, arsenic, selenium, and copper, the composition optimizes the mechanical and electrochemical properties of the battery grids. Tin and antimony contribute to the alloy's strength and corrosion resistance, while arsenic and selenium improve the alloy's casting characteristics and enhance the depth of discharge capabilities. Copper aids in increasing the conductivity of the grids, thereby improving the overall performance of the battery. This composition allows for a more efficient production process, reducing the need for manual intervention and enabling continuous grid production. The strategic combination of these elements results in a battery grid that offers improved cyclic performance and longevity, addressing the limitations of traditional gravity-cast grids.

In various embodiments of the lead antimony alloy composition, the proportions of the constituent elements can be adjusted to improve specific performance characteristics of the lead-acid battery grids. For instance, in one embodiment, the lead content is increased to about 98.91 weight percent to enhance the conductivity and structural integrity of the grids, while maintaining the alloy's malleability for efficient processing. The content of the lead can be kept within range of 94.55 – 98.91 weight percent. In another embodiment, the tin content is kept within the range of 0.02 to 2.0 weight percent, which can improve the corrosion resistance and mechanical strength of the grids, making them suitable for applications requiring extended battery life. Similarly, the antimony content can be varied up to 1.0 to 3.0 weight percent to enhance the cyclic performance and depth of discharge capabilities, particularly in high-demand applications such as automotive batteries. The arsenic content, ranging from 0.05 to 0.25 weight percent, can be adjusted to improve the alloy's resistance to oxidation, thereby prolonging the grid's lifespan. Selenium, present in amounts from 0.01 to 0.1 weight percent, can be tailored to enhance the alloy's grain structure, contributing to improved mechanical properties and ease of processing during the rolling and punching stages. Copper, also ranging from 0.01 to 0.1 weight percent, can be incorporated to increase the alloy's tensile strength and thermal conductivity, which are important for maintaining grid performance under varying environmental conditions. These embodiments demonstrate the adaptability of the alloy composition to meet diverse functional requirements.

The Alloy Composition of the Antimonial Lead according to the present invention is provided below:

The Alloy Composition of the Antimonial Lead:
Elements Alloy Composition (Wt. %)
Lead (Pb) 94.55 – 98.91
Tin (Sn) 0.02 – 2.0
Antimony (Sb) 1.0 – 3.0
Arsenic (As) 0.05 – 0.25
Selenium (Se) 0.01 – 0.1
Copper (Cu) 0.01 – 0.1

In another embodiment, the method for producing lead-acid battery grids involves using a twin roll caster to form a raw strip with a thickness ranging from about 6 to about 12 millimeters, which is then subjected to a rolling process comprising fewer than five stages to achieve a strip thickness between about 0.5 and about 1.5 millimeters. This rolling process can be adapted to include different configurations of rolling mills, such as a combination of cold and hot rolling stages, to optimize the mechanical properties of the strip.

In another embodiment, the punching step is performed using a continuous punching machine, which may be equipped with advanced automation features to enhance the efficiency and precision of grid production. This machine can be configured to accommodate various grid designs and dimensions, allowing for flexibility in the manufacturing process. Additionally, the method may include a step of trimming the edges of the rolled strip prior to punching to ensure uniform grid dimensions, which can be achieved using laser cutting or mechanical shearing techniques. Furthermore, the lead antimony alloy composition can be specifically formulated to improve the depth of discharge capability and cyclic performance of the resulting battery grids, with variations in the alloying elements' concentrations to tailor the grids for specific battery applications. The method may also incorporate a step of coiling the punched grids for subsequent processing in a pasting operation, where the coiling mechanism can be designed to handle different grid sizes and shapes, ensuring seamless integration into the battery assembly line.

The operational principle of this method for producing lead-acid battery grids lies in the strategic combination of material composition and manufacturing processes to optimize the production of lead-acid battery grids. By utilizing a lead antimony alloy composition that includes elements such as tin, antimony, arsenic, selenium, and copper, the method improves the mechanical and electrochemical properties of the grids. Tin and antimony contribute to the alloy's strength and corrosion resistance, while arsenic and selenium enhance casting characteristics and depth of discharge capabilities. Copper increases conductivity, thereby improving battery performance.

The casting step, responsible for forming a raw strip, plays a significant role in achieving a uniform and consistent base material that can be processed effectively in subsequent stages. The rolling step reduces the strip's thickness, which is necessary for achieving the desired grid dimensions and mechanical properties. This reduction in thickness is accomplished through fewer than five rolling stages, which streamlines the process and reduces labor intensity compared to traditional methods.

The punching step transforms the rolled strip into battery grids, facilitating precise and efficient production. This step is designed to improve the performance characteristics of the grids by ensuring uniformity and consistency in grid design, which is important for optimal battery function.

Overall, the method provides a continuous and automated approach to grid production, significantly reducing manual labor and improving productivity. The method addresses the limitations of traditional gravity casting methods by offering a more efficient and effective solution for manufacturing lead-acid battery grids with enhanced cyclic performance and depth of discharge capabilities.

The present invention will be better understood with reference to the accompanying figures.

FIG. 1 shows a block diagram illustrating the method of production for a lead antimony alloy composition, specifically designed for manufacturing lead-acid battery grids. This figure highlights the sequential steps involved in the continuous production process, emphasizing the integration of advanced techniques to enhance efficiency and performance, including the use of the Twin Roll Caster ?, the 6mm Cast Antimonial Strip ?, and the Rolling Mills ?-?, ultimately producing the 1mm Rolled Antimonial Strip ?, which is then processed by the Strip Coiler ?. Additionally, FIG. 2 introduces components such as the 1mm Rolled Antimonial Strip 7, the Punched Antimonial Grid 11, the Punching Die 10, the De-coiler 9, and the Grid Coiler 12, which are integral to the overall production process. The process begins with a Twin Roll Caster ?, which is responsible for casting the lead antimony alloy into a strip. This component plays an important role as it forms the initial 6mm Cast Antimonial Strip ?. The twin roll casting technique is significant because it allows for the rapid solidification of the alloy, resulting in a uniform and consistent strip that serves as the foundation for subsequent processing stages, including the 1mm Rolled Antimonial Strip 7. Following the casting, the 6mm Cast Antimonial Strip ? undergoes a series of rolling operations to reduce its thickness. This process is accomplished through multiple stages of rolling mills, specifically Rolling Mill – Stage I ?, ?, ?, and ?. Each stage progressively reduces the thickness of the strip, resulting in a final thickness of 1mm Rolled Antimonial Strip ?. The use of multiple rolling stages represents an innovative approach, as it ensures precise control over the strip's dimensions and mechanical properties, which are important for the performance of the final battery grids. Once the strip has been rolled to the desired thickness, the strip emerges as a 1mm Rolled Antimonial Strip ?. This component is then directed to a Strip Coiler ?, which winds the strip into coils for ease of handling and further processing. The coiling step plays a significant role in maintaining the integrity of the strip and facilitating the transport to the next phase of production, which involves punching the strip to form grids for battery electrodes, utilizing a Punched Antimonial Grid 11 and a Punching Die 10. The process begins with the De-coiler 9 and concludes with the Grid Coiler 12. The described method represents a significant advancement over traditional grid production techniques, offering a continuous and highly automated process that reduces manual labor and enhances the depth of discharge capabilities of the resulting lead-acid battery grids. The integration of twin roll casting ? and multi-stage rolling ?-? not only streamlines the manufacturing process but also improves the overall quality and performance of the battery grids, particularly with the use of the 1mm Rolled Antimonial Strip ? and the Punched Antimonial Grid 11.

The present invention offers several advantages in the production of lead-acid battery grids, primarily through the use of a specialized lead antimony alloy composition and a continuous manufacturing method. These advantages include:
1. Enhanced Depth of Discharge Capability: The inclusion of elements such as tin, antimony, arsenic, selenium, and copper in the alloy composition improves the electrochemical properties of the battery grids. This strategic combination enhances the depth of discharge capability, allowing batteries to deliver more energy during each cycle, which is particularly beneficial for applications requiring high energy output.
2. Improved Cyclic Performance: The optimized alloy composition contributes to the durability and longevity of the battery grids. By enhancing the mechanical strength and corrosion resistance, the grids can withstand repeated charge and discharge cycles without significant degradation, resulting in longer battery life and reduced maintenance costs.
3. Increased Automation and Efficiency: The continuous grid production method, which includes casting, rolling, and punching steps, results in higher automation and significantly reduces manual labor. This streamlined process allows for higher throughput and consistent quality in grid production, leading to improved productivity.
4. Reduced Manpower Requirements: The automated nature of the continuous production method minimizes the need for manual intervention, reducing manpower requirements and associated labor costs. This efficiency is achieved through the integration of advanced machinery and optimized processes.
5. Uniform Grid Dimensions: The method includes a step of trimming the edges of the rolled strip prior to punching, ensuring uniform grid dimensions. This precision in manufacturing results in grids that fit seamlessly into battery assemblies, improving overall battery performance and reliability.
6. Flexibility in Grid Design: The continuous punching machine can be configured to accommodate various grid designs and dimensions, providing flexibility in manufacturing. This adaptability allows manufacturers to tailor grid specifications to meet specific application requirements, such as automotive or industrial energy storage systems.
7. Reduced Material Waste: The efficient use of materials in the casting and rolling processes minimizes waste, contributing to cost savings and environmental sustainability. The precise control over alloy composition and grid dimensions ensures optimal use of resources.
8. Improved Thermal Stability: The alloy composition is designed to enhance the thermal stability of the battery grids, making them suitable for high-temperature applications. This characteristic is important for maintaining battery performance in challenging environmental conditions.

By leveraging these advantages, the present invention provides a comprehensive solution to the challenges faced in traditional lead-acid battery grid manufacturing, offering superior performance, reliability, and efficiency. The combination of the specialized alloy composition and continuous production method results in improved cyclic capabilities, further enhancing the overall effectiveness of the battery grids.
,CLAIMS:
1. A lead antimony alloy composition for use in manufacturing lead-acid battery grids, comprising: lead, tin, antimony, arsenic, selenium, and copper.

2. The lead antimony alloy composition as claimed in claim 1, wherein the lead is present in an amount ranging from about 94.55 to about 98.91 weight percent.

3. The lead antimony alloy composition as claimed in claim 1, wherein the tin is present in an amount ranging from about 0.02 to about 2.0 weight percent.

4. The lead antimony alloy composition as claimed in claim 1, wherein the antimony is present in an amount ranging from about 1.0 to about 3.0 weight percent.

5. The lead antimony alloy composition as claimed in claim 1, wherein the arsenic is present in an amount ranging from about 0.05 to about 0.25 weight percent.

6. The lead antimony alloy composition as claimed in claim 1, wherein the selenium is present in an amount ranging from about 0.01 to about 0.1 weight percent.

7. The lead antimony alloy composition as claimed in claim 1, wherein the copper is present in an amount ranging from about 0.01 to about 0.1 weight percent.

8. A method for producing lead-acid battery grids, comprising the steps of:
providing a lead antimony alloy composition comprising lead, tin, antimony, arsenic, selenium, and copper;
casting the alloy composition to form a raw strip;

rolling the cast strip to reduce its thickness; and
punching the rolled strip to form battery grids,
wherein the method is configured to enhance the performance characteristics of the lead-acid battery grids.

9. The method as claimed in claim 8, wherein the casting step involves using a twin roll caster to form the raw strip with a thickness ranging from about 6 to about 12 millimeters.

10. The method as claimed in claim 8, wherein the rolling step comprises fewer than five stages to achieve a final strip thickness between about 0.5 and about 1.5 millimeters.

11. The method as claimed in claim 8, wherein the punching step is performed using a continuous punching machine to enhance the efficiency of grid production.

12. The method as claimed in claim 8, further comprising the step of trimming the edges of the rolled strip prior to the punching step to ensure uniform grid dimensions.

13. The method as claimed in claim 8, wherein the lead antimony alloy composition is specifically formulated to improve the depth of discharge capability of the resulting battery grids.

14. The method as claimed in claim 8, wherein the lead antimony alloy composition is designed to enhance the cyclic performance of the resulting battery grids.

15. The method as claimed in claim 8, further comprising the step of coiling the punched grids for subsequent processing in a pasting operation.