A pole group head of a single lead-acid battery

Abstract

The present invention discloses a terminal block for a single lead-acid battery, belonging to the technical field of lead-acid battery manufacturing. The terminal block is formed by tightly combining a main body made of a non-polar polymer material (such as polypropylene) and an insert made of a polar polymer material (such as ABS). The surface of the main body is provided with a raised texture (depth 0.5-1mm) and reinforcing ribs to enhance the heat-sealing bonding strength and deformation resistance with the sealing bag; the insert is designed with a multi-level sealing structure of an annular outer cavity and a cylindrical inner cavity, the lead pole is fixed by a polar adhesive, and a pH-responsive adhesive and an acid-resistant modified epoxy adhesive are used to achieve sealing and bonding. This structure solves the problem of traditional mechanical seal failure caused by space limitations in high-width-to-thickness ratio batteries, significantly improving the sealing reliability and life of the battery during long-term use.

Description

Technical Field

[0001] The invention belongs to the technical field of lead-acid battery manufacturing, and in particular relates to a pole group head of a single lead-acid battery. Background Art

[0002] The terminal block of a lead-acid battery is a key component of the cell packaging, and its structural sealing directly affects the battery life and safety. Traditional solutions mostly use single-polarity material integral injection molding, and achieve sealing through mechanical extrusion force between the lead terminal and the plastic. However, as battery design develops towards a high aspect ratio (L / W ≥ 8), the battery cell tends to be thinner to improve the heat dissipation efficiency of the formation, and the bottleneck of the traditional structure is becoming increasingly prominent: on the one hand, mechanical extrusion sealing requires a large assembly space to be reserved, which cannot be implemented in thin batteries with limited terminal block width; on the other hand, a single material cannot simultaneously meet the requirements of heat sealing with non-polar polymer sealing bags and high-strength bonding with the lead terminal (polar material is required). The conflict in material properties leads to a sharp increase in the risk of interface sealing failure.

[0003] In addition, the strong acid environment (pH=0-4) inside the lead-acid battery causes continuous corrosion to the sealing interface. Traditional epoxy adhesives are prone to brittle cracking under long-term acid corrosion, causing microcracks on the interface and gradually expanding, eventually leading to electrolyte leakage. However, the structural rigidity of the wide and thin pole group head is insufficient, and the heat sealing process is prone to warping and deformation due to stress concentration. In addition, the smooth surface leads to a limited sealing contact area. The leakage-free pressure resistance value of the traditional structure is usually less than 40kPa, which is difficult to meet the requirements of high-reliability applications. Existing improvement technologies such as composite sealing covers or acid-resistant rubber coatings can partially improve the tolerance of materials, but they have not been able to solve systemic problems such as polar / non-polar material interface synergy, dynamic acid etching self-repair, and wide and thin structure deformation resistance.

[0004] Therefore, there is an urgent need for a breakthrough pole group head structure that can be compatible with the spatial constraints of high aspect ratio battery cells, achieve efficient sealing of multi-material interfaces, and have self-healing capabilities in strong acid environments, thereby fundamentally improving the long-term sealing reliability of lead-acid batteries. Summary of the Invention

[0005] The purpose of the present invention is to provide a modular, sealed and self-repairing soft-pack battery cell packaging structure, which realizes an easy-to-maintain and corrosion-resistant pole group head and battery cell assembly solution through a non-polar / polar polymer material composite structure and a special adhesive design.

[0006] A pole cluster head for a single lead-acid battery includes a main body and an embedded part. The main body is made of a non-polar polymer material, and the embedded part is made of a polar polymer material. The main body and the embedded part are tightly bonded, and the pole cluster head is installed on a battery cell. The outside of the battery cell is covered with a sealing bag, which is also made of a non-polar polymer material. Based on the requirements of the heat sealing process, the main body needs to be made of a non-polar polymer material for heat-sealing with the sealing bag. Since the pole cluster head of the present invention has a structural feature with a relatively high width-to-thickness ratio, traditional mechanical extrusion sealing (using the compression force between the lead pole and the non-polar polymer material to achieve sealing) cannot be applied due to insufficient space, so a polar adhesive needs to be used to fix the lead pole. To this end, the embedded part (polar polymer material) is provided to provide a bonding interface with the lead pole and ensure that the embedded part and the main body are tightly bonded.

[0007] A terminal block for a single lead-acid battery, with a main body having a width of L and a thickness of W, and a width-to-thickness ratio of L / W ≥ 8. This block is designed to accommodate battery cells with a width-to-thickness ratio greater than 8. In actual manufacturing, this ratio is typically ≤ 20. A larger width-to-thickness ratio results in a thinner cell, allowing the water bath to more effectively dissipate heat generated by charging and discharging during the formation process. Under appropriate width and thickness conditions, a larger width-to-thickness ratio results in a lower internal temperature during the formation process.

[0008] A pole cluster head of a single lead-acid battery has raised textures on both sides of the main body. The raised textures are parallel lines, there is at least one line, and the depth range is 0.5mm-1mm. The pole cluster head of the present invention is installed on the battery cell. A heat sealing process is used to combine the sealing bag and the pole cluster head to wrap the battery cell. By limiting the depth range of the raised texture, the contact area between the sealing bag and the pole cluster head is optimized to ensure that the raised texture can enhance the bonding force without causing a decrease in material strength due to excessive depth, thereby balancing the sealing performance and structural reliability. When there are one, two or three raised textures, the leakage-free pressure resistance values ​​between the sealing bag and the pole cluster head are 40kPa, 70kPa, and 90kPa, respectively. A single texture meets the basic sealing requirements, and multiple textures provide redundant sealing protection. Users can flexibly select design specifications according to the battery operating conditions.

[0009] A single-cell lead-acid battery terminal block features a surface-mounted reinforcing rib structure. This rib structure enhances the body's resistance to deformation and ensures the integrity of the sealing interface. The ribs also disperse stress generated during packaging, preventing warping and seal failure due to material fatigue over time.

[0010] A terminal block for a single lead-acid battery. The insert features an annular outer cavity with positioning ribs within it, and a cylindrical inner cavity running through the center. The insert creates a multi-level sealed cavity structure with an annular outer cavity and a cylindrical inner cavity, separating the conductive and sealing functions. The annular outer cavity serves as a glue reservoir, ensuring even distribution along the insert's surface, while the positioning ribs provide guidance and positioning.

[0011] A terminal block for a single lead-acid battery. The lead terminals are mounted on the battery cell and fit into a cylindrical inner cavity. This creates a conductive path and preserves the lead terminal's welding port. The tight fit between the lead terminals and the cylindrical inner cavity prevents acid from seeping into the terminal block. Before the terminal block is installed on the battery cell, a fixed amount of sealing glue is added to the cylindrical inner cavity and the annular outer cavity. The lead terminals of the battery cell then fit into the cylindrical inner cavity, squeezing the internal sealing glue into the annular outer cavity. Once the glue solidifies, the lead terminals are secured.

[0012] A terminal block for a single-cell lead-acid battery. The main body is made of polypropylene, and the inner insert is made of an acrylonitrile, butadiene, and styrene terpolymer (ABS). The contact area between the terminal block and the sealing bag is made of polypropylene (PP). Under certain temperature conditions, the heat-sealed connection with the sealing bag creates a strong bond, making it difficult for the two to separate, thus ensuring the seal within the battery cell. The PP material has a pH tolerance range of approximately 2-12 at 80°C, which is greater than the pH tolerance of ABS used in conventional lead-acid battery cell covers (approximately 4-10), and exhibits superior acid and corrosion resistance. A single-layer or multi-layer textured structure is designed on the contact surface between the terminal block and the sealing bag to increase the heat-seal contact surface area and enhance the bonding strength between the two. The inner insert's contact surface with the lead terminal is made of ABS plastic. ABS contains acrylonitrile polar groups, resulting in a higher surface energy of approximately 36-42 mN / m compared to non-polar plastics such as PE and PP. This allows for easier physical adsorption or chemical bonding with the lead element in lead-acid batteries. Other plastics, such as PP, are completely non-polar materials with low surface energy and inherently weak bonding with metal. Therefore, the contact area between the insert and the lead terminal is made of ABS, a polar material. Furthermore, ABS is stronger than PP, providing superior protection for the lead terminal. Compared to traditional integrated terminal cluster structures, assembling the main body and insert using two different materials, ABS and PP, fully leverages the advantages of both materials.

[0013] A lead-acid battery terminal block has a pH-responsive adhesive added to the interface between the main body and the embedded components. The pH-responsive adhesive contains acid-responsive microcapsules. The pH-responsive adhesive includes a borate bond prepolymer, and may also contain epoxy acrylic hybrid resin, TPO-L (ethyl 2,4,6-trimethylbenzoylphenylphosphonate), and diisopropylbenzene peroxide. The shell material of the acid-responsive microcapsules is polymethyl methacrylate-co-maleic anhydride, and the core material is pentaerythritol triacrylate. The dynamic borate bonds in the dynamic borate bond prepolymer trigger recombination when etched by electrolyte (pH ≤ 3), and the microcapsule shell regenerates under the influence of H + At concentrations above 0.15mmol / L, it selectively breaks, releasing repair monomers to rapidly fill interfacial microcracks. Simultaneously, the borate network dynamically restructures to enhance molecular entanglement at the non-polar polymer / polar polymer interface, achieving both self-repair and mechanical reinforcement in acid-etching environments. The epoxy-acrylic hybrid resin provides a rigid framework for the adhesive, while also forming a dense protective layer that slows electrolyte erosion. TPO-L, a UV-triggered curing agent, and dicumyl peroxide, a heat-triggered curing agent, work together in a gradient curing process to fully cure the adhesive, ultimately ensuring a tight seal between the embedded component and the main body, and ensuring the internal sealing of the cell after the terminal group and sealed bag are encapsulated.

[0014] A lead-acid battery terminal block seals the contact surface between the lead terminal and the internal insert with epoxy adhesive. The epoxy adhesive contains an acid-resistant modified component composed of a long-chain alkyl organosilicon compound and tetraethoxysilane. The internal insert is made of ABS. Epoxy adhesive typically exhibits a high bond strength (approximately 5-20 MPa) with ABS. The polar surface of ABS (containing acrylonitrile and styrene) forms hydrogen bonds or dipole interactions with the polar groups of the epoxy adhesive (such as hydroxyl and epoxy groups). Due to its low surface energy and inert oxide layer, lead has a moderate bond strength (approximately 2-10 MPa). Modified epoxy adhesive (such as by adding a toughening agent) is required to improve the bonding properties, ensuring a tight seal between the lead terminal block and the internal insert, and ensuring the internal sealing of the battery cell after the terminal block and the sealed bag are encapsulated. The epoxy adhesive sealant addresses the interfacial sealing issue between the ABS internal insert and the lead terminal block. The epoxy adhesive chemically bonds to the polar surface of the ABS, forming a stable seal. The modified adhesive adapts to the low surface energy of lead, preventing debonding. The bonding strength of epoxy adhesives to ABS and lead, and the underlying mechanism, primarily depends on the surface properties of the materials and interfacial interactions. For ABS, epoxy adhesives typically exhibit moderate to high bonding strength, making them difficult to peel from after curing. This is due to hydrogen bonding or dipole interactions between the polar surface of ABS (containing acrylonitrile and styrene) and the polar groups of the epoxy adhesive (such as hydroxyl and epoxy groups). Lead, on the other hand, has low to moderate bonding strength due to its low surface energy and inert oxide layer, necessitating the addition of toughening agents to improve adhesion. The addition of silicone and silane compounds to epoxy adhesives enhances acid resistance and flexibility. Silicones enhance the elasticity of the colloid and adapt to temperature deformation, while silane compounds react with acidic environments to form an inert layer, which slows corrosion and effectively extends the life of lead-acid batteries.

[0015] A terminal block for a single lead-acid battery features rounded edges on both sides of the main body. This rounding prevents the soft packaging material from being pierced by the sharp edges of the main body during heat sealing, which could lead to damage and leakage of the electrolyte package.

[0016] The advantages of this invention lie in its composite structure of a non-polar PP main component and a polar ABS insert. The PP main component is compatible with heat sealing in sealing bags, while the ABS insert is highly bonded to the lead terminal via a polar adhesive, addressing the problem of high-aspect-ratio battery cells that cannot be sealed using traditional mechanical extrusion due to insufficient space. The combination of a pH-responsive adhesive automatically releases repair monomers to fill cracks during electrolyte etching (pH ≤ 3), reconstructing the borate network and achieving self-healing of the interface. The raised surface texture (depth 0.5-1mm) of the main component provides a gradient pressure resistance of 40-90kPa, while the annular cavity glue storage structure ensures uniform glue distribution and curing, forming a triple sealing barrier of "heat sealing interface + bonding interface + dynamic repair." The aspect ratio design improves heat dissipation efficiency during the formation process, reducing internal cell temperatures. The PP material has a better acid resistance range than traditional ABS. Combined with a modified epoxy adhesive (containing silicone / silane), it delays lead terminal corrosion and extends battery cycle life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0018] Figure 1 This is a schematic diagram of the pole group head of the present invention being installed on the battery cell.

[0019] Figure 2 Schematic diagram of the battery cell structure of the present invention.

[0020] Figure 3 This is a schematic diagram of the bottom of the pole group head of the present invention.

[0021] Figure 4 This is a graph showing the impact resistance test data of the ABS sample of Example 2 of the present invention.

[0022] Figure 5 This is the cell width-to-thickness ratio-forming temperature difference curve of Example 2 of the present invention.

[0023] Description of the accompanying drawings: 1-main body, 2-embedded part, 3-battery cell, 4-sealing bag, 11-raised texture, 12-reinforcement rib, 21-annular outer cavity, 22-cylindrical inner cavity, 23-positioning rib, 31-lead pole. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] The following first describes the concepts involved in this application with reference to the accompanying drawings. It should be noted that the following description of each concept is intended only to make the content of this application easier to understand and does not limit the scope of protection of this application. At the same time, the embodiments and features in the embodiments of this application can be combined with each other unless there is a conflict. The following detailed description of this application will be made with reference to the accompanying drawings and in conjunction with the embodiments.

[0026] Example 1:

[0027] Refer to the attached Figure 1 As shown, a terminal block for a single-cell lead-acid battery comprises a main body 1 and an insert 2. The main body 1 is made of a non-polar polymer material, while the insert 2 is made of a polar polymer material. The main body 1 and the insert 2 are tightly bonded, and the terminal block is mounted on a battery cell 3. The battery cell 3 is covered with a sealing bag 4, also made of a non-polar polymer material. Due to the heat sealing process requirements, the main body 1 must be made of a non-polar polymer material to achieve a heat-sealable bond with the sealing bag 4. Due to the high width-to-thickness ratio of the terminal block of the present invention, traditional mechanical extrusion sealing (which utilizes the compressive force between the lead terminal 31 and the non-polar polymer material to achieve a seal) is not applicable due to insufficient space. Therefore, a polar adhesive is required to secure the lead terminal 31. To this end, the insert 2 (made of a polar polymer) is provided to provide a bonding interface with the lead terminal 31 and ensure a tight bond between the insert 2 and the main body 1.

[0028] Refer to the attached Figure 1 As shown, a terminal block for a single lead-acid battery has a main body 1 with a width L and a thickness W, and a width-to-thickness ratio L / W ≥ 8. This is used to accommodate and install battery cells 3 with a width-to-thickness ratio greater than 8. A larger width-to-thickness ratio makes the battery cell 3 relatively thinner, allowing the water bath to more effectively remove heat generated by charging and discharging during the formation process. Under appropriate width and thickness conditions, a larger width-to-thickness ratio results in a lower internal temperature during the formation process.

[0029] Refer to the attached Figure 1 , Attachment Figure 3As shown, a pole group head of a single lead-acid battery has a raised texture 11 on both sides of the main body 1. The raised texture 11 is a parallel texture, the number of the textures is at least one, and the texture depth ranges from 0.5mm to 1mm. The pole group head of the present invention is installed on the battery cell 3. The sealing bag 4 is combined with the pole group head by a heat sealing process to wrap the battery cell 3. By limiting the depth range of the raised texture 11, the contact area between the sealing bag 4 and the pole group head is optimized to ensure that the raised texture 11 can enhance the bonding force without causing a decrease in material strength due to excessive depth, thereby balancing the sealing performance and structural reliability. When the raised texture 11 is one, two or three, the leakage-proof pressure value between the sealing bag 4 and the pole group head is 40kPa, 70kPa, and 90kPa, respectively. A single texture meets the basic sealing requirements, and multiple textures provide redundant sealing protection. Users can flexibly select design specifications according to the battery operating conditions.

[0030] Refer to the attached Figure 1 The figure shows a terminal block for a single lead-acid battery. Ribs 12 are provided on the surface of the main body 1. These ribs enhance the main body 1's resistance to deformation and ensure the integrity of the sealing interface. Ribs 12 also disperse stress generated during packaging, preventing warping of the main body 1 and seal failure due to material fatigue after long-term use.

[0031] Refer to the attached Figure 3 As shown, a terminal block for a single lead-acid battery has an inner insert 2 with an annular outer cavity 21, which is equipped with positioning ribs 23. A cylindrical inner cavity 22 runs through the center of the insert 2. The insert 2 forms a multi-level sealed cavity structure with an annular outer cavity 21 and a cylindrical inner cavity 22, separating the conductive and sealing functions. The annular outer cavity 21 serves as a glue reservoir, ensuring even distribution of the glue along the surface of the insert 2, while the positioning ribs 23 provide guidance and positioning.

[0032] Refer to the attached Figure 1 , Attachment Figure 2 As shown, a terminal block for a single lead-acid battery has a lead post 31 mounted on the battery cell 3, which mates with the cylindrical inner cavity 22. The mate between the lead post 31 and the cylindrical inner cavity 22 establishes a conductive path and preserves the lead post 31's welding port. The lead post 31 and the cylindrical inner cavity 22 tightly mate to prevent acid from seeping into the terminal block. Before the terminal block is installed on the battery cell 3, a fixed amount of sealing glue is added to the cylindrical inner cavity 22 and the annular outer cavity 21. The lead post 31 of the battery cell 3 mates with the glue-added cylindrical inner cavity 22, squeezing the internal sealing glue into the annular outer cavity 21. After the glue solidifies, the lead post 31 is secured.

[0033] Refer to the attached Figure 1The figure shows a terminal block for a single-cell lead-acid battery. The main component 1 is made of polypropylene, and the inner insert 2 is made of ABS. The contact portion of the sealing bag 4 with the terminal block is made of polypropylene (PP). Under certain temperature conditions, the heat-sealed connection with the sealing bag 4 creates a strong bond, making it difficult for the two to separate, thus ensuring the seal within the battery cell 3. PP has a pH tolerance range of approximately 2-12 at 80°C, which is greater than the pH tolerance of ABS used in conventional lead-acid battery cell covers (approximately 4-10), and offers improved acid and corrosion resistance. A single or multi-layer raised texture 11 is designed on the contact surface between the terminal block and the sealing bag 4 to increase the heat-sealed contact surface area and enhance the bonding strength between the two. The contact surface of the inner insert 2 with the lead terminal 31 is made of ABS plastic. ABS contains acrylonitrile polar groups. Compared to non-polar plastics such as PE and PP, ABS has a higher surface energy of approximately 36-42 mN / m, making it more susceptible to physical adsorption or chemical bonding with the lead element in lead-acid batteries. Other plastics, such as PP, are completely non-polar materials with low surface energy and inherently weak bonding with metal. Therefore, the contact portion between the insert 2 and the lead terminal 31 is made of ABS polar material. Furthermore, ABS is stronger than PP, providing superior protection for the lead terminal 31. Compared to traditional integrated terminal cluster structures, assembling the main component 1 and insert 2 using two different materials, ABS and PP, fully leverages the advantages of both materials.

[0034] Refer to the attached Figure 1 As shown, a terminal head for a single lead-acid battery has a pH-responsive adhesive added to the interface between the main body 1 and the embedded part 2. The pH-responsive adhesive contains acid-responsive microcapsules. The pH-responsive adhesive ingredients include borate bond prepolymer, epoxy acrylic hybrid resin, TPO-L, and dicumyl peroxide. The shell material of the acid-responsive microcapsules is polymethyl methacrylate-co-maleic anhydride, and the core material is pentaerythritol triacrylate. The dynamic borate bond in the dynamic borate bond prepolymer triggers recombination when etched by electrolyte (pH ≤ 3), and the microcapsule shell is reconstituted under the influence of H + At concentrations greater than 0.15 mmol / L, the adhesive selectively breaks down, releasing repair monomers to rapidly fill interfacial microcracks. Simultaneously, the borate network dynamically restructures to enhance molecular entanglement at the non-polar polymer / polar polymer interface, achieving both self-repair and mechanical reinforcement in acidic environments. The epoxy-acrylic hybrid resin provides a rigid framework for the adhesive, while also forming a dense protective layer that slows electrolyte erosion. TPO-L, a UV-triggered curing agent, and dicumyl peroxide, a heat-triggered curing agent, work together in a gradient curing process to fully cure the adhesive, ultimately ensuring a tight seal at the interface between the insert 2 and the main body 1, and ensuring the internal sealing of the cell 3 after encapsulation by the terminal block and sealing bag 4.

[0035] Refer to the attached Figure 1As shown, the contact surface between the lead terminal 31 and the inner insert 2 of a single-cell lead-acid battery is sealed with epoxy adhesive. The epoxy adhesive contains an acid-resistant modified component composed of a long-chain alkyl organosilicon compound and tetraethoxysilane. The inner insert 2 is made of ABS. Epoxy adhesive typically exhibits a high bonding strength (approximately 5-20 MPa) between ABS's polar surface (containing acrylonitrile and styrene) and the epoxy adhesive's polar groups (such as hydroxyl and epoxy groups) form hydrogen bonds or dipole interactions. Due to its low surface energy and inert oxide layer, lead has a moderate bonding strength (approximately 2-10 MPa). Modification of the epoxy adhesive (e.g., by adding a toughening agent) is required to improve the bonding properties. This ensures a tight seal between the lead terminal 31 and the inner insert 2, and ensures the internal sealing of the battery cell 3 after the terminal terminal and the sealing bag 4 are encapsulated. The epoxy adhesive sealant solves the interfacial sealing problem between the ABS insert 2 and the lead terminal 31. The epoxy adhesive chemically bonds to the polar surface of the ABS, forming a stable seal. The modified colloid adapts to the low surface energy of lead, preventing debonding. The bonding strength of epoxy adhesive to both ABS and lead, and the mechanism behind it, primarily depend on the surface properties of the materials and interfacial interactions. For ABS, epoxy adhesives typically exhibit moderate to high bonding strength, making them difficult to peel from after curing. This is due to hydrogen bonding or dipole interactions between the polar surface of ABS (containing acrylonitrile and styrene) and the polar groups of the epoxy adhesive (such as hydroxyl and epoxy groups). However, for lead, due to its low surface energy and inert oxide layer, the bonding strength is low to moderate, requiring the addition of a toughening agent to improve adhesion. The addition of silicone and silane compounds to epoxy adhesives improves acid resistance and flexibility. Silicone enhances the elasticity of the adhesive and allows it to adapt to temperature deformation. Silane compounds react with acidic environments to form an inert layer, which slows corrosion and effectively extends the life of lead-acid batteries.

[0036] Example 2:

[0037] Step 1: Preparation of the head structure

[0038] Refer to the attached Figure 1 As shown, a main body 1 and an insert 2 are prepared. The main body 1 is injection molded from PP, with a thickness of 2.5 mm and a single raised texture 11 on both sides with a depth of 0.8 mm. The insert 2 is made of ABS material, with an annular outer cavity 21 with a width of 2.0 mm for storing sealing glue.

[0039] Step 2: Adhesive Preparation and Application

[0040] Prepare a pH-responsive adhesive. Its ingredients include: dynamic borate prepolymer (60-65wt%), acid-responsive microcapsules (15wt%, shell material: polymethyl methacrylate-co-maleic anhydride), epoxy-acrylic hybrid resin (20-25wt%), TPO-L (2.5-3wt%), and dicumyl peroxide (1.5-2wt%). Apply the adhesive using a three-roll transfer mechanism to a thickness of 18-23μm. Add 0.8-1.2wt% of a benzotriazole derivative to enhance pH sensitivity. Inject the prepared adhesive into the interface between main component 1 and insert 2.

[0041] Step 3: Gradient curing process execution

[0042] First, a 385nm UV light source (115mW / cm²) was used to vertically irradiate the adhesive layer for 11 seconds, achieving a surface crosslinking degree of over 83%. Within 0.5 seconds, the system switched to mid-wave infrared radiation, controlling the peak temperature at 75±3°C for 30 seconds to complete deep cationic polymerization, ensuring a ≤8% difference in curing between the inner and outer layers.

[0043] Step 4: Assemble the pole group head and lead pole

[0044] Refer to the attached Figure 1 , Attachment Figure 3 As shown, the lead pole 31 is inserted into the cylindrical inner cavity 22 of the insert 2. The annular outer cavity 21 is pre-injected with 1.5 mL of epoxy sealant, and the gap is evenly filled with the glue by squeezing.

[0045] Step 5: Sealing and heat sealing

[0046] Refer to the attached Figure 1 As shown, a heat seal is performed on the contact surface between the main body 1 and the PP sealing bag 4. The heating plate temperature is set to 180°C and the pressure is 0.3 MPa for 5 seconds. The 0.8 mm deep raised texture 11 on the surface of the main body 1 increases the heat seal contact area by 40%, increasing the seal strength to 90 kPa. The sealing bag 4 and the main body 1 are sealed together, ultimately completely covering the battery cell 3.

[0047] Step 6: Performance Verification Test

[0048] ABS protection performance test for lead pole 31: ABS samples were tested with a width of 10mm, a thickness of 4.05mm, a gauge length of 50mm, and a tensile speed of 200mm / min. The tensile strength of the ABS samples was greater than 50MPa, and the impact strength was greater than 20KJ / m 2 , has good impact resistance and can better protect the lead pole 31. The test results are shown in Table 1 and Appendix Figure 4 shown.

[0049] Table 1. Strength test results

[0050]

[0051] Sealing test: when there are one, two or three raised textures 11 on both sides of the pole group head, it is guaranteed that there is no leakage between the sealing bag 4 and the pole group head under pressures of 40kPa, 70kPa and 90kPa;

[0052] Mechanical strength test: Apply 10N·m torque to the ABS support layer to verify that there is no deformation;

[0053] Environmental resistance test: The initial temperature is 25℃, dropped to -40℃, kept warm for 6 hours, then raised to 120℃, kept warm for 6 hours. The time from -40℃ to 120℃ is set to 90 minutes. After 100 cycles, there is no structural deformation and the integrity meets the protection requirements.

[0054] Acid resistance test: The electrode group head was immersed in a sulfuric acid solution with a pH of 1 for 200 cycles. The pH test paper dipped in pure water was used to detect the lead electrode 31 position and the interface between the main part 1 and the embedded part 2. It was found that the pH test paper did not change color, and there was no crack or electrolyte penetration on the interface.

[0055] Cell 3 width-to-thickness ratio test: refer to the attached Figure 5 As shown, three cells assembled with three different electrode group heads with different aspect ratios were acid-filled using an acid filling machine. Each electrode group head had the same aspect ratio (L / W) as the corresponding electrode group head, with an acid density of 1.26 g / cm³ (25°C). The acid filling volume was 290 g. The three cell aspect ratios (L / W) were as follows: ① Soft-packed single cells of the present invention, aspect ratio = 12.25 (two groups); ② Soft-packed single cells of the present invention, aspect ratio = 8 (two groups); ③ Traditional single cells, aspect ratio = 2.4. Twelve cells of each type were acid-filled. After acid filling, each cell was placed in the same formation water bath set to 25°C. The cell temperature during formation was recorded using a paperless recorder. Two temperature probes were installed on each cell with three different aspect ratios, each attached to the center of the cell's side surface to ensure accurate temperature monitoring. All three cells were charged and discharged using a "modular 85h" formation process. While the charge and discharge process was running, a paperless recorder was used to record temperature data. The formation temperature difference curve shows that the larger the cell width-to-thickness ratio, the lower the maximum temperature during the formation process. When the cell width-to-thickness ratio was 12.25, the maximum temperature during the formation process was only 38.2°C; when the modular width-to-thickness ratio was 8, the maximum temperature during the formation process was 45.1°C; and when the cell width-to-thickness ratio was 2.4, the maximum temperature during the formation process was 52.3°C. The experimental results show that when the width-to-thickness ratio of cell 3 is larger, cell 3 becomes relatively thinner, allowing the water bath to more effectively remove the heat generated by the cell charge and discharge during the formation process. Under appropriate width and thickness conditions, a larger width-to-thickness ratio of cell 3 results in a lower internal temperature during the formation process.

[0056] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be a communication between the internal parts of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and do not impose any form of limitation on the implementation methods of the technology of the present invention. Any person skilled in the art may make slight changes to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0058] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of this application, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A pole group head of a single lead-acid battery, characterized by: The invention comprises a main body (1) and an embedded part (2), wherein the main body (1) is made of a non-polar polymer material, and the embedded part (2) is made of a polar polymer material. The main body (1) and the embedded part (2) are tightly bonded, and the pole group head is mounted on the battery core (3). A pH-responsive adhesive is added to the bonding interface of the main body (1) and the embedded part (2), and the pH-responsive adhesive contains acid-responsive microcapsules. The pH-responsive adhesive component includes a borate bond prepolymer, and the dynamic borate bond in the borate bond prepolymer triggers recombination when the electrolyte acid erodes. The shell of the acid-responsive microcapsule is in the presence of H + When the concentration is >0.15mmol / L, it selectively breaks and releases repair monomers to quickly fill the interface microcracks, achieving interface self-repair.

2. The pole group head of a single lead-acid battery according to claim 1, characterized in that: The main body (1) has a width of L and a thickness of W, and the width-to-thickness ratio L / W is ≥8.

3. The pole group head of a single lead-acid battery according to claim 1, characterized in that: The surfaces of both sides of the main body (1) are provided with raised textures (11), the raised textures (11) are parallel textures, the number of the textures is at least one, and the depth of the textures ranges from 0.5 mm to 1 mm.

4. The pole group head of a single lead-acid battery according to claim 1, characterized in that: A reinforcing rib (12) structure is provided on the surface of the main body (1).

5. The pole group head of a single lead-acid battery according to claim 1, characterized in that: An annular outer cavity (21) is provided inside the inner insert (2), a positioning rib (23) is provided inside the annular outer cavity (21), and a through cylindrical inner cavity (22) is provided in the middle of the inner insert (2).

6. The pole group head of a single lead-acid battery according to claim 5, characterized in that: A lead pole (31) is provided on the battery core (3), and the lead pole (31) and the cylindrical inner cavity (22) cooperate with each other.

7. The pole group head of a single lead-acid battery according to claim 6, characterized in that: The material of the main body (1) is polypropylene, and the material of the embedded part (2) is ABS.

8. The pole group head of a single lead-acid battery according to claim 7, characterized in that: The contact surface between the lead pole (31) and the embedded part (2) is sealed with epoxy glue, and the epoxy glue contains an acid-resistant modified component of a long-chain alkyl organic silicon compound and tetraethoxysilane.

9. The pole group head of a single lead-acid battery according to claim 1, characterized in that: The shell material of the acid-responsive microcapsule is polymethyl methacrylate-co-maleic anhydride, and the core material is pentaerythritol triacrylate.

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