High-performance agm separator for lead-acid battery and preparation method and application thereof

Abstract

The application provides a high-performance lead-acid battery AGM separator and a preparation method and application thereof, and is composed of 25-30SR glass fibers accounting for 40-50% of the total fiber mass, 30-40% of 30-35SR glass fibers, 3-18% of two-component organic fibers, 5-10% of 40-45SR glass fibers, 3-8% of 14-24SR centrifugal cotton and 1-3% of additive fumed silica; in the application, the chemical stability of the 25-30SR glass fibers is improved, corrosion is prevented and the service life of the separator is prolonged; the mechanical properties are guaranteed by the interpenetrating network structure formed by the two-component organic fibers and the buffering network formed by the 40-45SR glass fibers, so that the battery structure is stable and the performance deterioration is reduced; the pore structure is optimized by the specific glass fiber interweaving and the glass fiber, so that the electrolyte storage, ion transmission and active material migration are promoted; the fumed silica makes the fibers not easy to be mutually adhered and aggregated in the beating process, and the cycle life of the battery in the electric vehicle can be prolonged and the endurance attenuation can be reduced.

Description

Technical Field

[0001] This invention relates to the field of lead-acid battery separator manufacturing technology, specifically to a high-performance lead-acid battery AGM separator, its preparation method, and its application. Background Technology

[0002] In the field of lead-acid batteries, the performance of AGM separators has a significant impact on the overall battery performance. Traditional AGM separators for lead-acid batteries have many problems in practical applications.

[0003] On the one hand, the materials and structure of traditional AGM separators limit their ability to resist electrolyte corrosion. In the complex and corrosive chemical environment of lead-acid batteries, AGM separators are easily corroded by the electrolyte, exhibiting poor long-term stability. This can lead to structural damage to the AGM separator, affecting normal battery operation and reducing battery life. On the other hand, traditional AGM separators have shortcomings in mechanical properties. Under the pressure of battery assembly and the impact and vibration during use, AGM separators are prone to cracking or deformation. This not only affects the stability of the battery's internal structure but may also cause battery failure, reducing battery safety and reliability. Furthermore, the pore structure of traditional AGM separators is often suboptimal, with limited electrolyte storage space and insufficient ion conduction channels. This results in uneven electrolyte distribution within the AGM separator, low ion transport efficiency, and limitations on battery charge and discharge efficiency, failing to meet the rapid charge and discharge requirements of modern high-performance batteries.

[0004] In applications with high battery performance requirements, such as backup power for electric vehicles and communication base stations, batteries need frequent charging and discharging and must operate stably under complex conditions (such as vibration and temperature changes). These performance defects of traditional AGM separators severely affect battery performance and reliability in these scenarios, leading to reduced battery range and unstable backup power supply. Therefore, there is an urgent need for a high-performance AGM separator for lead-acid batteries that can overcome these problems, improving battery performance, stability, and durability under complex operating conditions to meet the pressing needs of practical applications.

[0005] In view of this, a high-performance lead-acid battery AGM separator, its preparation method and application are provided to overcome the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a high-performance lead-acid battery AGM separator, its preparation method, and its application, so as to solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides a high-performance lead-acid battery AGM separator, which is composed of 25-30°SR glass fiber (SR is Schöber degree, calculated based on drainage time, with a measurement range of 0-100 SR, the same below), 30-35°SR glass fiber, bicomponent organic fiber, 40-45°SR glass fiber, 14-24°SR centrifugal cotton, and additives such as fumed silica. Among them, 25-30°SR glass fiber accounts for 40%-50% of the total fiber mass, 30-35°SR glass fiber accounts for 30%-40% of the total fiber mass, 40-45°SR glass fiber accounts for 5%-10% of the total fiber mass, 14-24°SR centrifugal cotton accounts for 3%-8% of the total fiber mass, additives such as fumed silica account for 1%-3% of the total fiber mass, and bicomponent organic fiber accounts for 3%-18% of the total fiber mass. The bicomponent organic fiber is a combination of polyester fiber and polyacrylonitrile fiber in equal mass ratio, and the two work together to form a synergistic effect.

[0008] Furthermore, 30-35°SR glass fibers are combined with 25-30°SR glass fibers to form diverse pore structures.

[0009] Furthermore, the bicomponent organic fibers composed of polyester and polyacrylonitrile fibers form an interpenetrating network structure through a synergistic effect.

[0010] Furthermore, the porosity of the AGM partition is not less than 92%, and the liquid absorption rate is not less than 4.8 g / m².

[0011] A method for preparing a high-performance lead-acid battery AGM separator includes the following steps:

[0012] Pulping process: Using a pulper, add sulfuric acid solution to adjust the pH value of the pulping environment; weigh 25-30°SR glass fiber, 30-35°SR glass fiber, bicomponent organic fiber, 40-45°SR glass fiber and 14-24°SR centrifugal cotton according to the proportion, and slowly add them to the pulper. Add fumed silica during the pulping process. Fumed silica accounts for 1%-3% of the total fiber mass. It is used to prevent the fibers from sticking together and agglomerating during the pulping process, thereby improving the stability of the separator structure, corrosion resistance and reducing the short circuit failure rate inside the battery. Pulping is carried out at a speed of 1500 rpm for 60 minutes.

[0013] Water addition and subsequent treatment: Stir for 30 minutes when pulping has been completed; pour the fiber pulp into a special mold, apply 5MPa pressure to form, and dry at 80℃ for 24 hours; cut the dried AGM partition to a cutting accuracy of ±0.5mm, and perform appearance inspection and physical property testing.

[0014] Furthermore, the pH value of the pulping environment is controlled at 3.5.

[0015] Furthermore, during the water mixing process, the amount of deionized water is 5 times the total fiber mass, and the mixture is stirred at 1000 rpm.

[0016] The application of a high-performance lead-acid battery AGM separator in electric vehicle batteries and communication base station backup power supplies can significantly improve the battery's performance and durability under frequent charging and discharging, temperature changes and complex operating conditions, and ensure stable power supply.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] 1. In terms of chemical stability, the specific ratio of 25-30°SR glass fiber in the AGM separator of this high-performance lead-acid battery enables the separator to resist electrolyte corrosion, extend its life, overcome the problem of poor stability of traditional separators, and enhance the battery's durability and reliability.

[0019] 2. In terms of mechanical properties, a variety of fibers are reasonably combined, including bicomponent organic fibers forming an interpenetrating network structure, which gives the separator high strength and toughness, disperses and absorbs external stress, ensures the stability of the battery structure, and avoids short circuit failure; the 40-45°SR glass fiber woven network can buffer the stress changes of the plates and reduce separator damage and performance degradation.

[0020] 3. The optimization of pore structure is reflected in the fact that a specific ratio of 25-30°SR and 30-35°SR glass fibers interweave to form diverse pores, which is conducive to electrolyte storage and ion transport, improves charging and discharging efficiency, and meets the needs of rapid charging and discharging; 40-45°SR glass fibers can also refine the pores, block the migration of active substances, and improve safety and stability.

[0021] 4. Fumed silica has a high specific surface area and good dispersibility. It can adsorb onto the fiber surface, acting as a kind of "isolation" and "lubricant," making it less likely for the fibers to stick together or agglomerate during pulping. This significantly improves the structural integrity of the separator, enhances tensile and compressive strength, extends battery cycle life, effectively slows down electrolyte erosion of the separator, reduces corrosion rate, minimizes corrosion pits and fiber breakage, lowers the rate of internal short-circuit failures caused by separator corrosion, ensures separator performance stability, improves battery reliability and lifespan, and enables the battery to perform better in different application scenarios.

[0022] 5. In terms of application performance, in electric vehicle batteries, its high porosity, high liquid absorption rate, and excellent mechanical properties ensure electrolyte supply and ion transport, extend cycle life, reduce range decay, and improve efficiency and economy. In communication base station backup power supplies, its high stability and long cycle life can provide stable power supply during mains power failures with minimal performance degradation. It ensures normal operation through fiber synergy, overcomes the problems of unstable power supply from traditional separators, improves reliability and stability, ensures the operation of communication networks, reduces failures, and has a positive driving effect on the development of the lead-acid battery field. It comprehensively solves the problems of traditional AGM separators, improves battery performance, stability, and durability under complex operating conditions, and meets practical application needs. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating the principle of a high-performance lead-acid battery AGM separator, its preparation method, and its application according to the present invention. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Please see Figure 1 The present invention provides a technical solution: Example 1

[0026] Synergistic benefits of material composition and structure:

[0027] Synergistic effects of various fiber components:

[0028] 25-30°SR glass fiber and 30-35°SR glass fiber are not only well-matched in proportion (accounting for 45% and 35% of the total fiber mass, respectively, within their respective reasonable ranges of 40%-50% and 30%-40%), but their chemical stability and mechanical strength properties also complement each other. The former exhibits a structural integrity retention rate of up to 98.5% in highly corrosive electrolytes, laying the foundation for the overall separator's corrosion resistance and structural stability; the latter focuses on constructing diverse pore structures (porosity of 48% and pore size of 0.8-45 micrometers). Together, they ensure the performance balance of the separator under different operating conditions. For example, under long-term high-load charge and discharge conditions and with fluctuations in electrolyte impurities, this combination can effectively prevent the separator from failing due to corrosion or structural deformation, extending the battery cycle life by 32%, a significant advantage compared to ordinary separators.

[0029] The bicomponent organic fiber, composed of polyester and polyacrylonitrile fibers in a 50%:50 ratio (a reasonable range of 3%-18% of the total fiber mass), forms an interpenetrating network structure through synergistic effects. The polyester fibers provide a tensile strength of 4.5 MPa and an elongation at break of 28%, ensuring the mechanical integrity of the separator; it remained unbroken and undeformed after 120 impacts with a 22g acceleration. The polyacrylonitrile fibers achieve an electrolyte adsorption rate of up to 96% and control the electrolyte concentration deviation within ±2.5%, optimizing the ion transport environment, improving battery charge-discharge performance, and increasing energy conversion efficiency by 15%. After 1200 temperature cycles (-15℃-65℃), the separator maintained good integrity and stability, effectively adapting to the battery's requirements at different operating temperatures and reducing performance fluctuations caused by temperature changes.

[0030] 40-45°SR glass fiber accounts for 7% of the total fiber mass (within the range of 5%-10%), and its high strength (tensile strength up to 5.2MPa, compressive strength of 4.0MPa) complements the high toughness and good adsorption properties of 14-24°SR centrifugal cotton (accounting for 3% of the total fiber mass, within the range of 3%-8%). In the battery positive and negative electrode plate expansion and contraction simulation test, after withstanding 120 cycles of 6% volume change stress, the separator did not crack or deform, and the pore structure was optimized, improving the pore uniformity by 48%, effectively blocking the migration of active materials in the positive and negative electrode plates, reducing the migration rate by 85%. After withstanding 250 cycles of 18g acceleration impact test, the separator maintained good toughness and no structural damage, and the amount of electrolyte adsorbed could reach 8.5 times its own mass. The two work together to ensure the structural stability of the separator and the reasonable distribution of the electrolyte under different environmental conditions, thereby improving the battery's capacity retention rate by 22% at low temperatures (-12℃) and by 18% at high temperatures (55℃), and expanding the battery's applicable temperature range to -32℃ to 68℃.

[0031] Structural characteristics and related benefits:

[0032] The diverse pore structure formed by combining 30-35°SR glass fibers and 25-30°SR glass fibers (48% porosity and pore size 0.8-45 micrometers) provides ample and suitable storage space for the electrolyte, ensuring that the electrolyte can fully wet every corner of the separator throughout the entire battery charge-discharge cycle, providing a stable and favorable dielectric environment for ion transport. Simultaneously, this diverse pore structure significantly reduces the resistance to ion transport within the separator, increasing ion migration rate by 55% and battery charge-discharge efficiency by 22%. In high-rate charge-discharge scenarios, such as the fast-charging requirements of electric vehicles, this structure effectively reduces charging time (28% shorter than ordinary separators) and provides stronger and longer-lasting power output during discharge (20% higher discharge power output).

[0033] The bicomponent organic fibers, composed of polyester and polyacrylonitrile fibers, form an interpenetrating network structure through a synergistic effect, enhancing the integrity and stability of the separator. In simulated battery transportation collision and vibration tests, the separator showed no cracking or deformation after 120 impacts with an acceleration of 22g, effectively ensuring the integrity and stability of the battery's internal structure, guaranteeing continuous normal operation, reducing the risk of battery failure due to separator damage, and improving the reliability of the battery system.

[0034] Performance parameter advantages:

[0035] The AGM separator boasts a porosity of up to 93% (not less than 92%) and a liquid absorption rate of 5.0 g / m² (not less than 4.8 g / m²). High porosity means the separator has ample internal space for electrolyte storage and ion transport, acting like a spacious highway network that provides convenient channels for electrolyte flow and ion migration, significantly improving battery charge and discharge efficiency. High liquid absorption rate indicates the separator's strong adsorption capacity for electrolyte, acting like a highly efficient sponge that can quickly and massively absorb and store electrolyte. This ensures that even under complex operating conditions, such as acceleration, deceleration, and turning in electric vehicles, the electrolyte remains stably distributed within the separator, providing a stable environment for ion transport and thus improving overall battery performance. For example, during rapid acceleration and deceleration of electric vehicles, electrolyte distribution stability is improved by 38%, effectively avoiding problems such as localized overheating or insufficient reaction caused by uneven electrolyte distribution, ensuring consistent and stable battery performance.

[0036] Key role of preparation method:

[0037] Optimization of the pulping process:

[0038] Using a pulper, sulfuric acid solution was added to adjust the pulping pH to 3.5. At this pH, the surface hydrolysis of the fibers increased roughness by 65%, increasing friction and facilitating fiber dispersion. Fiber was added proportionally, along with 2% fumed silica by weight of the total fiber mass during pulping. Fiber was added slowly to prevent aggregation. The fumed silica adsorbed onto the fiber surface. At a high-speed stirring speed of 1500 rpm, the average diameter of fiber agglomerates decreased from approximately 150.23 micrometers to approximately 60.15 micrometers, a reduction of 60.0%; the standard deviation of fiber distribution per unit area decreased from approximately 35.42 to 21.25, an improvement in uniformity of approximately 40.0%. After 60 minutes of pulping, the fibers formed a uniform network structure, ensuring the uniformity of the AGM separator porosity, with the deviation reduced from ±15.32% to within ±9.85%, an improvement of approximately 35.7%. This uniform structure is fundamental to ensuring the good performance of the AGM separator. A more uniform porosity further improves electrolyte storage and ion conduction, ultimately increasing the battery's charge and discharge efficiency. In battery charge and discharge efficiency tests, comparing lead-acid batteries of the same specifications but using AGM separators with and without added fumed silica, the battery with added fumed silica showed an increase in charge and discharge efficiency from 80.12% to approximately 92.35% under 1C charge and discharge conditions, an improvement precisely calculated to be 15.3%.

[0039] Precise control of water mixing and subsequent treatment:

[0040] During the 30-minute pulping process, deionized water, five times the total fiber mass, is slowly added. Water serves as both a diluent and lubricant, and the mixture is stirred at 1000 rpm for 30 minutes to ensure uniform fiber dispersion into a stable slurry. The slurry is then poured into a mold and molded under 5 MPa pressure, resulting in tightly interwoven fibers and a fixed pore structure. Drying at 80℃ for 24 hours yields a water evaporation rate of 0.48 g / h, preserving both structure and efficiency. Cutting precision is controlled within ±0.5 mm, and post-cutting appearance and physical performance are inspected to ensure no damage, uniform pore size, and satisfactory performance. Precise water mixing and subsequent processing steps guarantee the physical structural integrity and performance consistency of the separator, preventing performance degradation due to defects during processing and providing a reliable foundation for high-performance battery operation.

[0041] Performance in application areas:

[0042] Advantages of battery applications in electric vehicles:

[0043] In electric vehicle batteries, the AGM separator, due to its high porosity, high electrolyte absorption rate, and excellent mechanical properties, ensures a stable supply of electrolyte and smooth ion transport even under frequent charging and discharging and complex vibration environments. Its cycle life is extended by 32% compared to ordinary separators, effectively reducing battery replacement frequency and lowering operating costs. The range degradation rate is reduced by 22%. In daily use of electric vehicles, whether it's frequent start-stop driving in urban areas or long-distance highway driving, this AGM separator ensures stable battery performance, improving the efficiency and economy of electric vehicles. For example, during a long trip, an electric vehicle using an AGM separator experiences less range fluctuation compared to a vehicle using an ordinary separator, allowing for more precise trip planning and reducing extra charging time and costs caused by range anxiety.

[0044] Benefits of backup power supply for communication base stations:

[0045] In backup power supplies for communication base stations, its high stability and long cycle life ensure that the battery can quickly and stably power communication equipment during mains power failures, with minimal performance degradation during long-term backup. The power supply response time during mains power failures is reduced by 18%, enabling faster resumption of normal operation of communication equipment and reducing the risk of communication interruptions due to power outages. The performance degradation rate during long-term backup (one year) is controlled within 4%, and the battery's operational stability is improved by 32% when exposed to varying ambient temperatures (-18℃ to 55℃), effectively reducing the risk of communication failures due to power supply issues, ensuring the stable operation of communication base stations, and guaranteeing the reliability and continuity of communication networks. Under extreme weather conditions, such as extreme heat or severe cold, the AGM separator maintains the battery's optimal performance, providing continuous and stable power support to communication base stations.

[0046] Regarding the structural stability of the separator, the structural integrity was monitored in real-time and with precision during accelerated aging experiments simulating battery charge-discharge cycles. Without added fumed silica, after 500 cycles, approximately 30.15% of the separators showed significant structural deformation and localized damage, as detected by X-ray imaging and image analysis. With added fumed silica (4%), this proportion was only about 5.23% under the same experimental conditions, representing an 82.7% improvement in structural integrity retention. The tensile and compressive strengths of the separators were tested using specialized materials mechanics testing equipment. Without added fumed silica, the average tensile strength was approximately 1.23 MPa, and the compressive strength was approximately 2.52 MPa. After adding fumed silica, the tensile strength increased to 1.64 MPa (an increase of 33.3%), and the compressive strength increased to 3.23 MPa (an increase of approximately 28.2%). Based on this improved structural stability, in specific application scenarios (such as a temperature range of 25℃-40℃ and a depth of discharge of 60%-80%), the average lifespan of batteries without added fumed silica is 400-500 cycles, based on a large sample size analysis. However, the average lifespan of batteries with added fumed silica is extended to approximately 600-800 cycles, representing a 50%-60% increase compared to batteries without added silica.

[0047] Regarding the corrosion resistance of the separator, in a simulated corrosive environment experiment, the AGM separator was immersed in a highly corrosive solution with a composition similar to that of lead-acid battery electrolyte (sulfuric acid concentration of 30%-35%, containing small amounts of impurity ions such as iron and copper ions, with concentrations of 10ppm-20ppm). The mass loss rate of the separator was precisely measured every 24 hours. The mass loss rate of the separator without added fumed silica after 100 hours of immersion averaged approximately 10.25% after multiple measurements. The mass loss rate of the separator with added fumed silica (5%) was only about 6.53%, and the corrosion rate was reduced by 36.3%. After a long-term immersion experiment (500 hours), the microstructure of the separator was carefully observed using a high-resolution scanning electron microscope. The surface of the separator without added fumed silica showed a large number of corrosion pits, approximately 50-60 per square millimeter, and severe fiber breakage, with an average reduction in fiber diameter of about 20.35%. The separator surface with added fumed silica is relatively smooth, with only 10-15 corrosion pits per square millimeter, and the fiber diameter is reduced by an average of about 12.12%, while the fiber structure remains relatively intact. This indicates that fumed silica effectively slows down the electrolyte's erosion of the separator, significantly ensuring the separator's performance stability during long-term use, greatly reducing the probability of internal short circuits and other failures caused by separator corrosion, resulting in smaller performance fluctuations and higher reliability throughout the battery's lifespan. For example, in a batch of 100 comparative test batteries, the failure rate of internal short circuits due to separator corrosion in batteries without added fumed silica was approximately 15%, while this failure rate in batteries with added fumed silica was reduced to less than 5%. Example 2

[0048] Material composition:

[0049] 25-30°SR glass fiber: accounting for 42% of the total fiber mass. Although it possesses a certain degree of chemical stability, it can withstand 1000 hours of immersion in the highly corrosive electrolyte of lead-acid batteries (sulfuric acid concentration of approximately 30%-35%, containing trace amounts of iron ions, copper ions, and other impurities at a concentration of approximately 5-15 ppm), maintaining a 95% structural integrity rate. However, compared to Example 1, its corrosion resistance is somewhat weakened under long-term high-load use. Its tensile strength reaches 3.5 MPa, but under extreme conditions, its support strength for the separator structure is slightly inferior. For example, after withstanding 800 impacts with a 15g acceleration, the separator structure deforms by approximately 5%, which is higher than in Example 1.

[0050] 30-35°SR glass fiber: accounting for 38% of the total fiber mass. The pore structure constructed in combination with 25-30°SR glass fiber is relatively good, with a porosity of 46% and a pore size distribution of 1-40 micrometers; however, the diversity is less than that of Example 1. This results in a reduction in the abundance of electrolyte storage space and ion conduction channels. In battery charge-discharge cycle tests, the electrolyte wetting time increased by 20%, the ion transport resistance increased by 30%, and the battery charge-discharge efficiency was affected to some extent. The charging time was 15% longer than in Example 1, and the discharge energy output decreased by 12%.

[0051] The bicomponent organic fiber accounts for 13% of the total fiber mass, with polyester fiber making up 60% and polyacrylonitrile fiber making up 40%. The relatively higher proportion of polyester fiber results in a tensile strength of up to 4.2 MPa and an elongation at break of 25%, leading to good mechanical properties of the separator and its ability to withstand a certain degree of external impact. After 100 impacts with a 20g acceleration, the separator showed no cracking or deformation. However, the lower proportion of polyacrylonitrile fiber results in a 92% electrolyte adsorption rate, leading to decreased electrolyte adsorption and distribution uniformity, poorer ion transport stability, and relatively larger voltage fluctuations during battery charging and discharging, ranging from approximately ±5%, compared to within ±2.5% in Example 1.

[0052] 40-45°SR glass fiber: accounting for 6% of the total fiber mass. The strength of the resulting fiber network and its effect on optimizing the pore structure are not as good as in Example 1. In the battery positive and negative electrode plate expansion and contraction simulation test, after being subjected to 100 cycles of 5% volume change stress, although the separator did not crack or deform, the structural deformation reached 8%, which is higher than in Example 1. Its improvement in pore uniformity is only 35%, the migration rate of the active material effectively blocking the migration of the positive and negative electrode plates is reduced to 75%, and the short-circuit resistance is also reduced, increasing the risk of internal short circuits in the battery.

[0053] 14-24°SR centrifugal cotton: accounting for 1% of the total fiber mass. Although its toughness and adsorption properties can play a certain role, adsorbing up to 7 times its own mass of electrolyte, its effect on improving overall durability and ensuring electrolyte supply is not as significant as in Example 1 due to its low content. Under long-term use or complex operating conditions, such as temperature cycling (-10°C to 60°C) testing, after 1000 cycles, the battery performance degrades relatively quickly, with a 15% decrease in capacity retention, while Example 1 only shows an 8% decrease.

[0054] Performance parameters: Porosity 92%, liquid absorption rate 4.9 g / m². The porosity and liquid absorption rate are slightly lower than in Example 1, resulting in relatively limited electrolyte storage and ion transport channels. In ion migration rate testing, it decreased by 18% compared to Example 1, leading to a decline in battery charge / discharge performance, a relatively high reduction in driving range, and a shortened cycle life. In specific application scenarios (e.g., temperature range 25℃-40℃, depth of discharge 60%-80%), the average lifespan of batteries without added fumed silica, based on a large sample size analysis, is 400-450 cycles, while Example 1's is approximately 600-800 cycles.

[0055] Preparation method:

[0056] Pulping process: The pH of the pulping environment was adjusted to 3.5. Fibers were weighed according to the specified ratio and slowly added to the pulper. Fumed silica, accounting for 1.5% of the total fiber mass, was added during the pulping process. Due to the low content of fumed silica, its effects on fiber dispersion, mechanical property improvement, electrolyte adsorption distribution optimization, and enhanced chemical stability were not as significant as in Example 1. At a high-speed stirring speed of 1500 rpm, the average diameter of the fiber aggregates decreased from approximately 120 micrometers to approximately 70 micrometers, a reduction of 41.7%; the standard deviation of fiber distribution per unit area decreased from approximately 32 to 25, and the uniformity improved by approximately 21.9%, both lower than in Example 1. The resulting fiber dispersion system exhibited slightly poor uniformity, leading to less than ideal structure and performance after the separator was formed.

[0057] Water addition and subsequent processing: Add 5 times the weight of the fiber in deionized water after 30 minutes of pulping, then stir at 1000 rpm for 30 minutes. Pour into a mold and pressurize at 5 MPa. Dry at 80℃ for 24 hours. Cut to a precision of ±0.5 mm and inspect. The steps are the same as in Example 1, but due to the difference in fiber raw materials, the final separator performance is not as good as in Example 1, and the stability and reliability exhibited in battery applications are relatively low.

[0058] Application Areas: Used in batteries for electric vehicles and backup power supplies for communication base stations. In electric vehicles, the reduction in driving range is slightly greater than in Example 1, approximately 25%, and the battery cycle life is slightly shorter. Under complex operating conditions such as frequent start-stop or high-speed driving, battery performance fluctuations are more pronounced. For example, in a 200km driving test, the battery voltage fluctuated 8 times, while Example 1 only fluctuated 3 times. In backup power supplies for communication base stations, the power supply stability is slightly worse during mains power failures, and the performance degradation rate of the backup separator is relatively high over long-term backup periods, reaching 8% within a one-year backup period, which may affect the normal operation of the communication base station during mains power outages. Example 3

[0059] Material composition:

[0060] 25-30°SR glass fiber: accounting for 48% of the total fiber mass. It exhibits high chemical stability; after 1200 hours of immersion in the aforementioned corrosive electrolyte environment, the structural integrity retention rate reaches 99%. However, due to its high content, the fibers are relatively tightly packed. This somewhat limits the effectiveness of other fibers; for example, the formation of the pore structure is not ideal, the electrolyte storage space is relatively reduced, and the adsorption and distribution of electrolyte by the bicomponent organic fibers are also somewhat hindered, affecting the improvement of battery charge and discharge efficiency.

[0061] 30-35°SR glass fiber: accounts for 32% of the total fiber mass. The pore structure formed in conjunction with 25-30°SR glass fiber is not sufficiently diverse, with a porosity of 45% and pore sizes ranging from 2-38 micrometers, resulting in relatively few ion conduction channels. During battery charging and discharging, ion transport speed slows down, charging time is extended by 25%, depth of discharge is limited, discharge energy output is reduced by 15%, and overall battery performance deteriorates.

[0062] Bicomponent organic fibers comprise 10% of the total fiber mass, with polyester fibers accounting for 40% and polyacrylonitrile fibers for 60%. The higher proportion of polyacrylonitrile fibers results in better electrolyte adsorption and distribution, achieving an adsorption rate of 97%. However, the lower proportion of polyester fibers leads to insufficient mechanical strength of the separator, with a tensile strength of only 3.0 MPa. During battery assembly and use, there is a risk of breakage or deformation, especially under significant external impacts. For example, after 150 impacts with a 25g acceleration, the separator has a 10% probability of breakage, which may damage the internal structure of the battery, affecting its normal operation and lifespan.

[0063] 40-45°SR glass fiber: accounting for 8% of the total fiber mass. It has a certain improvement effect on the strength and pore structure of the separator, with a tensile strength of 4.8MPa and a compressive strength of 3.5MPa. However, due to the overall unbalanced fiber ratio, it cannot fully exert its advantages. Its effect on enhancing tensile and compressive strength and optimizing electrolyte penetration and diffusion is limited, and it cannot effectively reduce the risk of internal short circuits in the battery, which has a certain impact on the long-term stability of the battery.

[0064] 14-24°SR centrifugal cotton: accounts for 2% of the total fiber mass. Its toughness and adsorption properties have limited effect on improving overall performance. It adsorbs 7.5 times its own mass of electrolyte. In terms of ensuring battery durability and electrolyte supply under complex working conditions, it is not as good as Example 1. In low-temperature environments or long-term use, the battery capacity retention rate decreases faster. In an environment of -10°C, after 800 charge-discharge cycles, the capacity retention rate decreases by 20%, while in Example 1 it only decreases by 12%.

[0065] Performance parameters: Porosity 92.5%, liquid absorption rate 4.85 g / m². These parameters differ from those of Example 1, affecting the interaction between the electrolyte and ions during battery charging and discharging, leading to a decline in overall battery performance. In electric vehicle applications, the reduction in driving range is significant, approximately 30%, and cycle life is shortened. In communication base station backup power applications, the decline in power supply stability and long-term backup performance is less ideal than in Example 1.

[0066] Preparation method:

[0067] Pulping process: Adjust the pulping pH to 3.5, weigh the fibers and slowly add them to the pulper along with fumed silica (2.5% of the total fiber mass), and pulp at 1500 rpm for 60 minutes. A slightly higher fumed silica content, while helpful for fiber dispersion (reducing the average diameter of fiber aggregates from approximately 130 micrometers to about 65 micrometers, a 50% decrease), may lead to excessive covering of the fiber surface. This affects the interaction between fibers, resulting in uneven structure after separator formation, impacting porosity and liquid absorption, and consequently affecting battery performance.

[0068] Water addition and subsequent processing: Pulping for 30 minutes, adding 5 times the fiber weight of deionized water, then stirring at 1000 rpm for 30 minutes, molding under 5 MPa pressure, drying at 80℃ for 24 hours, cutting accuracy ±0.5 mm and inspection. The process is similar to Example 1, but due to the ratio of fiber raw materials and additives, the final separator performance is not as good as Example 1, and performance instability is prone to occur during battery use.

[0069] Application areas: It has some application performance in electric vehicle batteries and communication base station backup power supplies. However, compared with Example 1, in electric vehicles, the battery performance deteriorates significantly under complex operating conditions, such as a large reduction in driving range and a shortened cycle life. In communication base station backup power supplies, the power supply stability and long-term backup performance deteriorate less than in Example 1, which may lead to insufficient power supply or power interruption for communication base stations when the mains power fails, affecting communication quality and reliability. Example 4

[0070] Material composition:

[0071] 25-30°SR glass fiber: accounting for 40% of the total fiber mass. It exhibits good chemical stability, maintaining 97% structural integrity after 1100 hours of immersion testing. However, compared to Example 1, its long-term corrosion resistance is slightly weaker, and its support for the partition structure may be insufficient under extreme conditions. Its tensile strength is 3.3 MPa, and after withstanding 700 impacts with an 18g acceleration, the partition structure deforms by approximately 6%.

[0072] 30-35°SR glass fiber: accounting for 40% of the total fiber mass. It forms a relatively good pore structure with a porosity of 47% and a pore size distribution of 1.2-42 micrometers. However, due to the change in proportion, its synergistic effect with 25-30°SR glass fiber is not as good as in Example 1, which has a certain impact on electrolyte storage and ion conduction efficiency. In battery charge-discharge cycle tests, the electrolyte wetting time increased by 18%, and the ion transport resistance increased by 28%.

[0073] Bicomponent organic fiber: accounting for 13% of the total fiber mass, with polyester fiber and polyacrylonitrile fiber each accounting for half. It exhibits good mechanical properties and electrolyte adsorption and distribution performance. The tensile strength of polyester fiber is 4.0 MPa, and the elongation at break is 26%. The electrolyte adsorption rate of polyacrylonitrile fiber is 95%. However, due to the change in the overall fiber ratio, its effect on improving the integrity and stability of the separator is not as significant as in Example 1. In simulated temperature cycling tests (-12℃-62℃), after 1100 cycles, the separator structure deformation was 10%, while in Example 1 it was 5%.

[0074] 40-45°SR glass fiber: accounting for 5% of the total fiber mass. The formed fiber network has limited effect on optimizing the separator strength and pore structure, with a tensile strength of 4.5 MPa and a compressive strength of 3.2 MPa. It lacks sufficient buffering capacity under varying battery plate stress and has weak short-circuit resistance. In a simulated expansion and contraction test of the battery's positive and negative plates, after withstanding 110 cycles of 4% volumetric stress change, the separator structure deformed by 10%, higher than in Example 1.

[0075] 14-24°SR centrifugal cotton: accounting for 2% of the total fiber mass. Its toughness and adsorption properties contribute relatively little to the overall battery performance improvement, adsorbing 7.2 times its own mass of electrolyte. Its effectiveness in ensuring battery durability and electrolyte supply under complex operating conditions is limited. Under long-term use or complex operating conditions, such as in environments with large humidity variations (30%-90%), after 900 charge-discharge cycles, the battery performance degradation rate reaches 18%, compared to 10% in Example 1.

[0076] Performance parameters: Porosity 92%, liquid absorption rate 4.82 g / m². Compared with Example 1, these parameters lead to a decrease in electrolyte storage and ion transport efficiency during charge and discharge, affecting the overall performance improvement of the battery. In the ion migration rate test, it decreased by 20% compared to Example 1, resulting in a decline in battery charge and discharge performance.

[0077] Preparation method:

[0078] Pulping process: The pH of the pulping environment was adjusted to 3.5. Fiber was slowly added to the pulper according to a specified ratio, with fumed silica added at 1% of the total fiber mass. The low fumed silica content had limited effect on fiber dispersion, mechanical property improvement, electrolyte adsorption distribution optimization, and enhanced chemical stability during the pulping process. At a high-speed stirring speed of 1500 rpm, the average diameter of fiber agglomerates decreased from approximately 140 micrometers to approximately 80 micrometers, a reduction of 42.9%; the standard deviation of fiber distribution per unit area decreased from approximately 34 to 28, and uniformity improved by approximately 17.6%, but this did not effectively improve the overall performance of the separator.

[0079] Water addition and subsequent treatment: Add 5 times the fiber weight of deionized water after 30 minutes of pulping, then stir at 1000 rpm for 30 minutes, mold under 5 MPa pressure, dry at 80℃ for 24 hours, and cut to an accuracy of ±0.5 mm and inspect. The steps are the same as in Example 1, but due to the ratio of fiber raw materials and additives, the final partition performance is not as good as in Example 1.

[0080] Application areas: Used in batteries for electric vehicles and backup power supplies for communication base stations. In electric vehicles, battery performance deteriorates significantly under long-term use and complex operating conditions, such as a large reduction in driving range (approximately 28%) and a shortened cycle life. In backup power supplies for communication base stations, power supply stability is poor during mains power failures, and the performance of backup batteries deteriorates rapidly over long-term use, with a performance degradation rate of up to 10% within a one-year backup period, affecting the normal operation of communication base station equipment.

[0081] Comparative Example 1:

[0082] Performance parameters:

[0083] The lower porosity and liquid absorption rate limit the storage of electrolyte and ion transport within the separator, resulting in low energy conversion efficiency during charging and discharging. In ion migration rate tests, the efficiency was reduced by 35% compared to Example 1, significantly shortening the driving range and drastically reducing cycle life. In specific application scenarios (such as a temperature range of 25℃-40℃ and a depth of discharge of 60%-80%), the average lifespan of batteries without added fumed silica, based on a large sample size analysis, was only 300-400 cycles, far lower than the 600-800 cycles of Example 1.

[0084] Preparation method:

[0085] Pulping process: The pH value of the pulping environment was 3.5. Fibers were weighed according to the specified ratio and slowly added to the pulverizer. Fumed silica, accounting for 0.5% of the total fiber mass, was added during the pulverizing process. Due to the extremely low content of fumed silica, the fiber dispersion was poor, easily leading to fiber agglomeration. At a high-speed stirring speed of 1500 rpm, the average diameter of the fiber agglomerates only decreased from approximately 180 micrometers to about 150 micrometers, a reduction of 16.7%; the standard deviation of fiber distribution per unit area decreased from approximately 40 to 35, and the uniformity improved by approximately 12.5%. This resulted in an uneven separator structure, poor mechanical properties, and uneven electrolyte adsorption and distribution, affecting the overall battery performance.

[0086] Water addition and subsequent processing: Add 5 times the weight of fiber in deionized water after 30 minutes of pulping, then stir at 1000 rpm for 30 minutes. Pour into a mold and pressurize at 5 MPa. Dry at 80℃ for 24 hours, with a cutting accuracy of ±0.5 mm and inspect. Although the preparation steps are similar to those in Example 1, due to the unreasonable ratio of fiber raw materials and additives, the final separator performance is far inferior to that of Example 1. It cannot meet the normal use requirements in battery applications and is prone to various failures.

[0087] Application Areas: When applied to batteries for electric vehicles and backup power supplies for communication base stations, electric vehicles often suffer from poor battery performance, resulting in insufficient driving range and short cycle life, necessitating frequent battery replacements and increasing operating costs. For example, an electric vehicle using the separator in the comparative example may experience a more than 40% reduction in driving range compared to the same model using the separator in Example 1, and the battery may need replacement after only 1-2 years of use, while the separator in Example 1 can support a 3-5 year lifespan. In backup power supplies for communication base stations, unstable power supply during mains power failures can lead to unreliable power supply for extended periods, potentially causing communication base station equipment to cease operation and affecting the normal operation of the communication network. In the event of a mains power failure lasting more than 8 hours, the backup power supply for communication base stations using the separator in the comparative example may experience power outages or excessive voltage fluctuations leading to communication equipment restarts, while the separator in Example 1 can provide a stable power supply, ensuring the normal operation of the communication base station.

[0088] Comparative Example 2:

[0089] Material composition:

[0090] 25-30°SR glass fiber: accounting for 55% of the total fiber mass. Excessive 25-30°SR glass fiber makes the separator too rigid, reducing its flexibility and making it prone to breakage when the battery is subjected to external impact or vibration. Although its tensile strength reaches 4.2 MPa, its elongation at break is only 18%, and the probability of separator breakage reaches 20% after 100 impacts with a 30g acceleration. Simultaneously, the close arrangement of fibers restricts the pore structure, with a porosity of 44% and pore sizes distributed between 4-32 micrometers, which is detrimental to electrolyte permeation and ion transport, reducing battery charge and discharge efficiency.

[0091] 30-35°SR glass fiber: accounts for 25% of the total fiber mass. The pore structure formed by its combination with 25-30°SR glass fiber is not ideal, failing to provide sufficient storage space and good ion conduction channels for the electrolyte. This results in slow ion migration during charge and discharge, increased internal resistance, and significant heat generation, affecting battery performance and lifespan. In battery charge-discharge cycle tests, electrolyte wetting time increased by 40%, and ion transport resistance increased by 50%.

[0092] Bicomponent organic fibers account for 15% of the total fiber mass, of which polyester fibers account for 30% and polyacrylonitrile fibers account for 70%. Although the higher proportion of polyacrylonitrile fibers is beneficial for electrolyte adsorption, with an adsorption rate of up to 98%, the insufficient amount of polyester fibers results in insufficient mechanical strength of the separator, with a tensile strength of only 2.5 MPa. This makes it prone to damage during battery assembly and use. Moreover, the overall fiber ratio is unbalanced, affecting the synergistic effect of the bicomponent organic fibers and reducing the stability and reliability of the separator.

[0093] 40-45°SR glass fiber: accounts for 3% of the total fiber mass. Due to its insufficient content, it has a weak effect on improving the strength and pore structure of the separator. Its tensile strength is 4.0MPa and its compressive strength is 2.8MPa. It cannot effectively resist stress changes when the battery plates expand and contract, has low short-circuit resistance, and is prone to causing internal short circuits in the battery, threatening battery safety.

[0094] 14-24°SR centrifugal cotton: accounting for 2% of the total fiber mass. Its toughness and adsorption properties have limited effect on improving the overall battery performance. It adsorbs 6.5 times its own mass of electrolyte, making it difficult to ensure battery durability and a stable electrolyte supply under complex operating conditions, resulting in significant performance fluctuations under different environmental conditions. In an environment with varying humidity (20%-80%), after 700 charge-discharge cycles, the battery capacity retention rate decreased by 25%.

[0095] Performance parameters: Porosity is 91%, liquid absorption rate is 4.6 g / m². The relatively low porosity and liquid absorption rate limit the distribution of electrolyte within the separator and ion transport efficiency, resulting in significant energy loss during charging and discharging. This manifests as reduced driving range, increased charging time, and shortened cycle life. In electric vehicle applications, the driving range is reduced by approximately 35%, and the cycle life is shortened by approximately 40%. In communication base station backup power applications, power supply stability is insufficient, and long-term backup performance deteriorates significantly.

[0096] Preparation method:

[0097] Pulping process: Adjust the pulping pH to 3.5, weigh the fibers and slowly add them to the pulper along with fumed silica (3.5% of the total fiber mass), and pulp at 1500 rpm for 60 minutes. While excessive fumed silica content can help disperse fibers to some extent, reducing the average diameter of fiber aggregates from approximately 160 micrometers to around 60 micrometers (a reduction of 62.5%), it can also cause excessive coating on the fiber surface, affecting the interaction between fibers. This results in uneven structure after separator molding, negatively impacting porosity and liquid absorption, and ultimately reducing battery performance.

[0098] Water addition and subsequent processing: Pulping for 30 minutes, adding 5 times the fiber weight of deionized water, then stirring at 1000 rpm for 30 minutes, molding under 5 MPa pressure, drying at 80℃ for 24 hours, and cutting with a precision of ±0.5 mm and inspection. The preparation process is similar to Example 1, but due to the unreasonable ratio of fiber raw materials and additives, the final separator performance is poor, which can easily lead to performance instability and overheating during battery use, affecting the normal use and safety of the battery.

[0099] Application Areas: In electric vehicle batteries, poor battery performance often results in insufficient range and cycle life, causing inconvenience and increased operating costs for users. For example, electric motorcycles using the comparative separator may require charging after only 50-80 kilometers, and battery performance degrades significantly after about a year of use. In contrast, the separator in Example 1 can support a range of 150-200 kilometers and maintain stable performance for 3-5 years. In backup power supplies for communication base stations, low power supply reliability during mains power failures can lead to communication equipment malfunctions, affecting communication service quality and even causing communication outages. During a regional power grid failure, backup power supplies for communication base stations using the comparative separator may experience voltage drops and power outages, causing communication service interruptions in the surrounding area for several hours. The separator in Example 1, however, provides stable power, ensuring uninterrupted communication services.

[0100] Comparative Example 3:

[0101] Material composition:

[0102] 25-30°SR glass fiber: accounting for 40% of the total fiber mass. Its chemical stability is acceptable, with a structural integrity retention rate of 96% after a 1000-hour immersion test. However, due to variations in the proportion of other fibers, the overall synergistic effect is poor. During long-term battery operation, its protection and support for the separator structure are limited, making it prone to structural degradation. Its tensile strength is 3.2 MPa, and after withstanding 600 impacts with a 20g acceleration, the separator structure deforms by approximately 8%.

[0103] 30-35°SR glass fiber: accounts for 30% of the total fiber mass. The pore structure formed with 25-30°SR glass fiber is relatively simple, with a porosity of 42% and a pore size distribution of 5-30 micrometers. Its electrolyte storage and ion conduction performance are generally poor. During battery charging and discharging, it cannot provide an efficient ion transport channel, resulting in a slow charging and discharging rate and low energy conversion efficiency. In battery charge-discharge cycle tests, the electrolyte wetting time increased by 35%, and the ion transport resistance increased by 45%.

[0104] Bicomponent organic fibers account for 25% of the total fiber mass, with polyester and polyacrylonitrile fibers each making up half. Although the content of bicomponent organic fibers is high, the overall fiber ratio is unbalanced, preventing the formation of an ideal interpenetrating network structure in the separator. This results in insufficient mechanical properties and electrolyte adsorption and distribution performance. The tensile strength of polyester fibers is 3.8 MPa, and the elongation at break is 24%. The electrolyte adsorption rate of polyacrylonitrile fibers is 93%, which leads to localized deformation of the separator or uneven electrolyte distribution during battery use, affecting battery performance stability, with voltage fluctuations ranging from ±6%.

[0105] 40-45°SR glass fiber: accounting for 3% of the total fiber mass. Its low content means it has little effect on optimizing the separator strength and pore structure. Its tensile strength is 4.2 MPa and compressive strength is 3.0 MPa. It is difficult to effectively buffer stress changes in the battery plates, resulting in weak short-circuit resistance and increasing the risk of internal short circuits, which is detrimental to the safe and stable operation of the battery.

[0106] 14-24°SR centrifugal cotton: accounting for 2% of the total fiber mass. Its toughness and adsorption properties have limited impact on the overall battery performance. It adsorbs 6.8 times its own mass of electrolyte, making it difficult to guarantee battery durability and a continuous electrolyte supply under complex operating conditions. This leads to significant performance fluctuations and reduced reliability under different environmental conditions. In temperature cycling tests (-8℃-58℃), after 800 cycles, the battery capacity retention decreased by 22%.

[0107] Performance parameters: Porosity 91.5%, liquid absorption rate 4.7 g / m². These performance parameters are worse than those of Example 1, limiting the effective interaction of electrolyte and ions during charging and discharging, leading to a decline in overall battery performance. In electric vehicle applications, this manifests as reduced driving range; in communication base station backup power applications, it manifests as insufficient power supply stability. In electric vehicle applications, the driving range reduction is approximately 32%; in communication base station backup power applications, power supply stability is poor during mains power failures, and the performance of the backup separator deteriorates rapidly over long periods.

[0108] Preparation method:

[0109] Pulping process: The pH of the pulping environment was adjusted to 3.5. Fiber was slowly added to the pulper according to the specified ratio, without adding fumed silica. Due to the lack of fumed silica, the fibers were difficult to disperse during pulping and easily formed agglomerates. At a high-speed stirring speed of 1500 rpm, the average diameter of the fiber agglomerates decreased only from approximately 200 micrometers to about 180 micrometers, a reduction of 10%; the standard deviation of fiber distribution per unit area remained almost unchanged from approximately 45, while uniformity improved by about 2%. This resulted in uneven separator structure, poor mechanical properties, and uneven electrolyte adsorption and distribution, severely affecting the battery's charge-discharge performance and cycle life.

[0110] Water addition and subsequent processing: Add 5 times the weight of the fiber in deionized water after 30 minutes of pulping, then stir at 1000 rpm for 30 minutes, press at 5 MPa, dry at 80℃ for 24 hours, and cut to a precision of ±0.5 mm and inspect. Although the water addition and subsequent processing steps are the same as in Example 1, because no fumed silica is added during fiber pulping, the final separator performance is far inferior to that of Example 1, and various performance problems are prone to occur during battery use, such as increased internal resistance and reduced charge and discharge efficiency.

[0111] Application Areas: When used in electric vehicle batteries and communication base station backup power supplies, battery performance in electric vehicles deteriorates significantly under long-term use and complex operating conditions, resulting in reduced driving range, shortened cycle life, and a poor user experience. For example, electric vehicles using this comparative separator experience decreased acceleration performance, longer charging times, and severe battery capacity degradation after 2-3 years of use. In contrast, the separator of Example 1 maintains better acceleration performance and charging efficiency, with minimal capacity degradation even after 3-5 years of use. In communication base station backup power supplies, power supply stability is poor during mains power failures, and the performance of the long-term backup separator deteriorates rapidly, potentially causing power outages during mains power interruptions and affecting the normal operation of the communication network. During prolonged mains power failures, this comparative separator may fail to provide stable power, leading to the shutdown of some equipment in the communication base station and affecting the continuity and stability of communication services. The separator of Example 1, however, ensures the normal operation of the communication base station.

[0112] Comparative Example 4:

[0113] Material composition:

[0114] 25-30°SR glass fiber: accounting for 45% of the total fiber mass. It exhibits good chemical stability, maintaining 97.5% structural integrity after 1100 hours of immersion testing. However, due to the unreasonable combination and proportion of other fiber components, its advantages are difficult to fully realize, resulting in limited improvement in the overall performance of the separator during battery operation. Its tensile strength is 3.6 MPa, and after withstanding 700 impacts with a 22g acceleration, the separator structure deforms by approximately 7%.

[0115] 30-35°SR glass fiber: accounts for 35% of the total fiber mass. Although the porosity formed by combining it with 25-30°SR glass fiber has a certain effect, with a porosity of 46.5% and a pore size distribution of 1.5-38 micrometers, it cannot reach the optimal state due to the influence of subsequent processing factors. It hinders the efficiency of electrolyte storage and ion conduction. In the battery charge-discharge cycle test, the electrolyte wetting time is extended by 25% and the ion transport resistance increases by 35%.

[0116] Bicomponent organic fibers: accounting for 10% of the total fiber mass, of which polyester fibers account for 60% and polyacrylonitrile fibers account for 40%. The relatively higher proportion of polyester fibers ensures a certain level of mechanical properties of the separator, with a tensile strength of 4.0 MPa and an elongation at break of 23%. However, the lower proportion of polyacrylonitrile fibers leads to insufficient uniformity of electrolyte adsorption and distribution, affecting ion transport stability. As a result, the battery experiences significant voltage fluctuations during charging and discharging, with a voltage fluctuation range of approximately ±7%.

[0117] 40-45°SR glass fiber: accounting for 7% of the total fiber mass. Its inherent strength and ability to optimize pore structure cannot be fully realized due to other problems in the preparation process. The tensile strength is 4.6MPa and the compressive strength is 3.3MPa. The buffering effect during the expansion and contraction of the battery plates is not good, the short-circuit resistance needs to be improved, and the risk of internal short circuits in the battery is increased.

[0118] 14-24°SR centrifugal cotton: accounting for 3% of the total fiber mass. Its toughness and adsorption properties are difficult to maximize within the overall uncoordinated fiber combination. It adsorbs 7.3 times its own mass of electrolyte, resulting in only average performance in ensuring battery durability and electrolyte supply. Under complex operating conditions or long-term use, battery performance degrades relatively quickly. In a comprehensive environmental test with varying humidity and temperature (30%-90% humidity, -5℃-60℃ temperature), after 900 charge-discharge cycles, the battery capacity retention decreased by 20%.

[0119] Performance parameters: Porosity 92%, liquid absorption rate 4.8 g / m². Compared with Example 1, the performance parameters are inferior, resulting in unsatisfactory electrolyte storage and ion transport during charging and discharging, leading to a decline in overall battery performance. In electric vehicle applications, this results in reduced driving range and shortened cycle life; in communication base station backup power applications, it leads to insufficient power supply stability and a significant decline in long-term backup performance. In electric vehicle applications, the driving range is reduced by approximately 26%, and the cycle life is shortened by approximately 30%; in communication base station backup power applications, power supply stability is poor during mains power failures, and the separator performance degrades rapidly during long-term backup.

[0120] Preparation method:

[0121] Pulping Process: The pH of the pulping environment was adjusted to 4.5. Compared to the pH of 3.5 in Example 1, this pH is not conducive to the optimization of the fiber surface and the interaction between fibers. The degree of fiber hydrolysis reaction is different, resulting in poor fiber dispersion and poor uniformity of the formed fiber dispersion system, affecting the structure and performance of the separator. Fibers were weighed according to the ratio and slowly added to the pulper. During the pulping process, fumed silica was added at 2% of the total fiber mass. Although the content of fumed silica was the same as in Example 1, due to the unsuitable pH value, its effect on the fibers could not be fully utilized, and it could not effectively improve the separator performance. At a high-speed stirring speed of 1500 rpm, the average diameter of fiber agglomerates decreased from about 135 micrometers to about 75 micrometers, a decrease of 44.4%; the standard deviation of fiber distribution per unit area decreased from about 33 to 26, and the uniformity improved by about 21.2%, both lower than in Example 1. Pulping was carried out at a speed of 1500 rpm for 60 minutes.

[0122] Water addition and subsequent processing: Add 5 times the weight of the fiber in deionized water after 30 minutes of pulping, then stir at 1000 rpm for 30 minutes. Pour into a mold and pressurize at 5 MPa. Dry at 80℃ for 24 hours. Cut to a precision of ±0.5 mm and inspect. Due to pH issues during pulping, even with the same subsequent steps, the final separator performance was still inferior to Example 1, exhibiting poor stability and reliability in battery applications.

[0123] Application areas:

[0124] This technology is applied to batteries for electric vehicles and backup power supplies for communication base stations. In electric vehicles, batteries experience significant performance fluctuations under complex operating conditions, resulting in a marked reduction in driving range and a short cycle life, requiring more frequent maintenance and replacement. For example, in the operation of urban buses, battery packs using the comparative four-part separator may require in-depth maintenance and inspection every 3-4 months, and the battery range will decrease by about 30% when the vehicle is fully loaded. In contrast, the battery pack corresponding to Example 1 can maintain a stable operating cycle of 6-8 months, with a range reduction of less than 10%. In backup power supplies for communication base stations, power supply is unstable during mains power failures, and the separator performance degrades rapidly during long-term backup, potentially leading to abnormal operation of communication base station equipment and affecting the continuity and stability of communication services. For instance, in the event of a prolonged regional power outage, the backup power supply for communication base stations using the comparative four-part separator may experience unstable power supply voltage and current fluctuations after 2-3 days of power outage, affecting the normal operation of base station equipment. However, the separator in Example 1 can provide stable power supply for a week or even longer during power outages, ensuring the normal operation of communication base station equipment.

[0125] After detailed analysis and testing of the AGM separators in Examples 1, 2 to 4, and various comparative examples, the key data are compiled into the following table to more intuitively present the performance differences between them:

[0126] project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 25-30°SR glass fiber percentage (%) 45 42 48 40 / 55 40 45 30-35°SR glass fiber percentage (%) 35 38 32 40 / 25 30 35 Percentage of two-component organic fiber (%) 10 13 10 13 / 15 25 10 40-45°SR glass fiber percentage (%) 7 6 8 5 / 3 3 7 Percentage of 14-24°SR centrifugal cotton (%) 3 1 2 2 / 2 2 3 Porosity (%) 93 92 92.5 92 Not mentioned (below Example 1) 91 91.5 92 Liquid absorption rate (g / m²) 5.0 4.9 4.85 4.82 Not mentioned (below Example 1) 4.6 4.7 4.8 Ion migration rate (compared to Example 1) / 18% lower / Reduce by 20% Reduced by 35% / / 20% lower than Example 1 Percentage reduction in driving range (electric vehicle application, %) / Approximately 25% Approximately 30% Approximately 28% More than 40% Approximately 35% Approximately 32% Approximately 26% Cycle life (in cycles under specific scenarios) 600-800 400-450 / / 300-400 / / / Improvement in battery charging and discharging efficiency (compared to ordinary separators) / / / / / / / / Electrolyte wetting time (compared with Example 1) / Extend by 20% Extended by 25% Extended by 18% Extended by 30% (speculation) Extended by 40% Extended by 35% Extended by 25% Ion transport resistance (compared to Example 1) / Increase by 30% / Increased by 28% Increase by 40% (estimated) Increase by 50% Increase by 45% Increase by 35% Structural integrity retention rate (long-term immersion test, %) 98.5 95 99 97 90 / / / Tensile strength (MPa) / / / / / / / / Compressive strength (MPa) / / / / / / / / Performance in simulated battery transport collision and usage vibration tests No cracking or deformation after 120 impacts with an acceleration of 22g. No cracking or deformation after 100 impacts with a 20g acceleration. / / / / There is a risk of localized deformation or fracture after 100 impacts with 20g acceleration. / Performance in battery positive and negative electrode plate expansion and contraction simulation test The partition plate showed no cracking or deformation after withstanding 120 cycles of 6% volumetric stress. After withstanding 100 cycles of 5% volumetric stress, the diaphragm structure deformed by 8%. / After withstanding 110 cycles of 4% volumetric stress, the diaphragm structure deformed by 10%. / The probability of the partition breaking after withstanding 5% volumetric stress 100 times reaches 10%. / After withstanding 110 cycles of 4% volumetric stress, the diaphragm structure deformed by 10%. Power supply stability during mains power failure (backup power supply application for communication base stations) Stable power supply to ensure normal operation of communication base stations Power supply stability is slightly worse during mains power failures, and the performance degradation rate of long-term standby partitions is relatively high. The rate of decline in power supply stability and long-term standby performance is not as ideal as in Example 1. The power supply stability is poor during mains power failures, and the performance of the long-term standby partition degrades rapidly. Unstable power supply, unable to provide reliable power for extended periods. Low power supply reliability may lead to communication equipment failure. The power supply stability is poor during mains power failures, and the performance of the long-term standby partition degrades rapidly. Unstable power supply during mains power outages and rapid performance degradation of the partitions during long-term standby.

[0127] In summary, Example 1 is the optimal example.

[0128] Summarize:

[0129] I. Improved chemical stability:

[0130] Example 1 utilizes a specific proportion (45%) of 25-30°SR glass fiber. Its superior chemical stability allows the separator to maintain structural integrity for extended periods in the complex and highly corrosive electrolyte environment of lead-acid batteries, effectively preventing corrosion and significantly extending its lifespan. This provides a reliable guarantee for the long-term stable operation of the battery. In contrast, traditional AGM separators, due to material and structural limitations, have limited ability to resist electrolyte corrosion, exhibit poor long-term stability, and are prone to structural damage, thus affecting the normal operation and lifespan of the battery. This high-performance separator significantly overcomes this problem, reducing battery performance degradation and failure risks caused by corrosion, and improving the overall durability and reliability of the battery. In the long-term immersion test, the separator structure integrity retention rate of Example 1 was as high as 98.5%, while that of Comparative Example 1 was only 90%. Although Comparative Example 2 showed some chemical stability due to factors such as tight fiber arrangement and limited pore structure, its overall corrosion resistance was still inferior to that of Example 1. In actual battery operation, Comparative Example 1 may experience a significant performance decline due to corrosion after 1-2 years of use, while Example 1 can maintain stable operation for 3-5 years.

[0131] II. Enhanced mechanical properties:

[0132] Structural Stability: Example 1 utilizes a rational combination of various fibers, such as a 50 / 50 ratio of polyester and polyacrylonitrile fibers in a bicomponent organic fiber system. These fibers synergistically form an interpenetrating network structure, endowing the separator with excellent mechanical properties. Polyester fibers, with their unique molecular structure, contribute high strength and excellent toughness to the separator, effectively dispersing and absorbing external stresses generated during battery transportation and use due to bumps, collisions, frequent start-stop cycles, or driving on rough roads. This prevents damage such as breakage and deformation of the separator, strongly ensuring the integrity and stability of the battery's internal structure and guaranteeing continuous normal operation. This effectively solves the shortcomings of traditional AGM separators in terms of mechanical performance, avoiding internal short circuits and other malfunctions caused by separator damage, thus improving battery safety. For example, in simulated battery transportation collision and vibration tests, the separator in Example 1 showed no breakage or deformation after 120 impacts with a 22g acceleration, while Comparative Example 3, due to an imbalanced fiber ratio, could not fully utilize its mechanical properties and may show localized deformation or breakage risk after only 100 impacts with a 20g acceleration.

[0133] Anti-plate stress capability: 40-45°SR glass fiber accounts for 7% of the total fiber mass. Its high strength and good flexibility are perfectly combined, forming a dense and stable fiber network inside the separator. During battery charging and discharging, when the positive and negative plates expand and contract, this fiber network can effectively buffer and disperse stress changes with its excellent elasticity and toughness, preventing the separator from cracking or deforming due to stress. This further ensures that the normal operation of the battery is not affected, maintains the stability of the internal structure of the battery, and reduces separator damage and battery performance degradation caused by plate stress. In the battery positive and negative plate expansion and contraction simulation test, the separator of Example 1 did not crack or deform after 120 cycles of 6% volume change stress. However, due to insufficient 40-45°SR glass fiber content, the separator of Comparative Example 2 had a 10% probability of cracking after 100 cycles of 5% volume change stress. Comparative Example 4, due to pH value issues affecting the performance of glass fiber during the preparation process, had a 10% deformation of the separator structure after 110 cycles of 4% volume change stress. All of these are far inferior to Example 1.

[0134] III. Pore Structure Optimization:

[0135] Electrolyte Storage and Ion Transport: Example 1 utilizes a diverse porous structure constructed by interweaving 25-30°SR glass fiber (45%) and 30-35°SR glass fiber (35%). This provides ample and suitable storage space for the electrolyte, ensuring that the electrolyte fully wets every corner of the separator throughout the entire charge-discharge cycle, providing a stable and favorable medium environment for ion transport. Simultaneously, this diverse porous structure significantly reduces the resistance to ion transport within the separator, greatly improving the battery's charge-discharge efficiency. This allows the battery to complete the charging process in a shorter time and release more powerful and longer-lasting electrical energy during discharge. In contrast, traditional AGM separators have an unsatisfactory porous structure, limited electrolyte storage space, and insufficiently smooth ion conduction channels, resulting in uneven electrolyte distribution and low ion transport efficiency, thus limiting the battery's charge-discharge efficiency. This high-performance separator effectively improves this situation, meeting the requirements of modern high-performance batteries for rapid charge-discharge and improving the battery's power performance and efficiency. In the battery charge-discharge cycle test, the electrolyte wetting time of Example 1 was shortened by 35% and the ion transport resistance was reduced by 42%. In contrast, due to the simple and imperfect pore structure of Comparative Example 1, the electrolyte wetting time was extended by 30% and the ion transport resistance was increased by 40%. In Comparative Example 3, due to the simple pore structure, the electrolyte wetting time was extended by 35% and the ion transport resistance was increased by 45%. All of these results showed significant differences from Example 1.

[0136] Active material migration barrier: 40-45°SR glass fiber can further optimize the pore structure of the separator, making the pore distribution more uniform and dense. This not only facilitates the rapid penetration and uniform diffusion of electrolyte in the separator, creating better conditions for ion transport, but also effectively blocks the migration of active materials from the positive and negative plates, reducing the risk of internal short circuits in the battery. It acts like a safety barrier for the battery, further improving its safety and stability, and reducing the probability of battery performance degradation and failure caused by active material migration. In the active material migration test of the positive and negative plates, the migration rate of Example 1 decreased by 85%, while the migration rate of Comparative Example 2, due to insufficient 40-45°SR glass fiber content, decreased by only 75%. Comparative Example 4, due to poor fiber synergy, also showed an unsatisfactory migration rate reduction, increasing the risk of internal short circuits in the battery.

[0137] IV. Excellent application performance:

[0138] Applications in Electric Vehicle Batteries: In electric vehicle batteries, the high-performance AGM separator in Example 1, with its high porosity (93%), high liquid absorption rate (5.0 g / m²), and excellent mechanical properties, ensures a stable supply of electrolyte and smooth ion transport under frequent charging and discharging and complex vibration environments, effectively extending battery cycle life and reducing range degradation. For example, in the daily use of electric vehicles, whether it's frequent start-stop driving in urban areas or long-distance driving on highways, this AGM separator ensures stable battery performance, improving the efficiency and economy of electric vehicles. Compared to traditional AGM separators, it solves the problem of reduced battery range caused by poor separator performance, improves the overall performance and user experience of electric vehicles, and reduces operating costs, such as reducing the need for more frequent battery replacements due to battery performance degradation. In practical applications, the battery cycle life of Example 1 is 32% longer than that of ordinary separators, and the range degradation rate is reduced by 22%. In contrast, the range of Comparative Example 1 is seriously insufficient, the cycle life is short, and the battery needs to be replaced frequently. The range of Comparative Example 3 is reduced by about 32%, and the cycle life is shortened. None of them can meet the high performance requirements of electric vehicles.

[0139] Applications in Communication Base Station Backup Power Supplies: In communication base station backup power supplies, the high stability and long cycle life of the AGM separator in Example 1 ensure that the battery can quickly and stably power communication equipment during mains power failures, and that performance degradation is minimal during long-term backup. Even under conditions of significant environmental temperature variations, its excellent performance, particularly the synergistic effect of the bicomponent organic fibers, ensures normal battery operation, providing strong support for the stable operation of communication base stations and reducing the risk of communication failures due to power supply issues. Traditional AGM separators in communication base station backup power applications often suffer from performance defects, resulting in unstable power supply during mains power failures and rapid performance degradation during long-term backup, affecting communication service quality and continuity. This high-performance separator effectively overcomes these problems, improving the reliability and stability of communication base station backup power supplies, ensuring the normal operation of communication networks, and reducing communication interruptions and service quality degradation caused by power failures, thus possessing significant social and economic value. In the application of backup power for communication base stations, Example 1 shows that the power supply response time is shortened by 18% during mains power failure, the performance degradation rate during long-term backup (one year) is controlled within 4%, and the battery working stability is improved by 32% when the ambient temperature changes (-18℃-55℃). In contrast, Comparative Example 1 shows unstable power supply during mains power failure and cannot provide reliable power supply for a long time. Comparative Example 2 shows low power supply reliability during mains power failure, which may lead to communication equipment failure. Comparative Example 4 shows unstable power supply during mains power failure and rapid performance degradation of the separator during long-term backup. All of these make it difficult to ensure the stable operation of the communication base station.

[0140] In summary, this high-performance lead-acid battery AGM separator exhibits superior characteristics in terms of material composition, preparation method, and application performance. It comprehensively solves the problems existing in traditional AGM separators, significantly improving the battery's performance, stability, and durability under complex operating conditions. This meets the urgent needs of practical applications such as electric vehicles and communication base station backup power supplies for high-performance batteries, and plays a positive role in promoting the development of the lead-acid battery field. Through detailed comparative analysis of the examples and comparative examples, the advantages of Example 1 in various aspects and its key role in improving the overall battery performance are more clearly demonstrated, providing a strong reference for further research, production, and application of high-performance lead-acid battery AGM separators.

Claims

1. A high performance lead-acid battery AGM separator characterized in that, The AGM separator is composed of 25-30°SR glass fiber, 30-35°SR glass fiber and double-component organic fiber, and 40-45°SR glass fiber and 14-24°SR centrifugal cotton, additive fumed silica; The 25-30°SR glass fiber accounts for 40%-50% of the total fiber mass, the 30-35°SR glass fiber accounts for 30%-40% of the total fiber mass, the 40-45°SR glass fiber accounts for 5%-10% of the total fiber mass, the 14-24°SR centrifugal cotton accounts for 3%-8% of the total fiber mass, the additive fumed silica accounts for 1%-3% of the total fiber mass, and the double-component organic fiber accounts for 3%-18% of the total fiber mass. The 30-35°SR glass fiber and the 25-30°SR glass fiber cooperate to form a pore structure, and the synergistic effect of the polyester fiber and the polyacrylonitrile fiber group forms an interpenetrating network structure, and the porosity of the AGM separator is not less than 92%, and the liquid absorption rate is not less than 4.8 g / m².

2. A method of making a high performance lead-acid battery AGM separator based on the high performance lead-acid battery AGM separator of claim 1, characterized in that, The method comprises the following steps: A beating process is performed using a beater, and sulfuric acid solution is added to adjust the pH value; 25-30°SR glass fiber, 30-35°SR glass fiber, double-component organic fiber, 40-45°SR glass fiber and 14-24°SR centrifugal cotton are weighed according to the proportion, and are slowly added to the beater; additive fumed silica is added during the beating process, and the beating is performed at a speed of 1500 revolutions per minute for 60 minutes; Water is slowly added during the beating process, and after the water addition is completed, stirring is performed for 30 minutes; the fiber slurry is poured into a special mold, a pressure of 5 MPa is applied for molding, and drying is performed at 80°C for 24 hours; the dried AGM separator is cut according to a cutting accuracy of ±0.5 mm, and appearance inspection and physical property detection are performed.

3. A method of making a high performance lead acid battery AGM separator as defined in claim 2, characterized by: The pH value of the beating environment during the beating process is controlled to be 3.

5.

4. A method of making a high performance lead acid battery AGM separator as defined in claim 2, characterized by: During the water mixing process in the water mixing and subsequent treatment, the deionized water is 5 times the total fiber mass, and subsequent stirring is performed at 1000 revolutions per minute.

5. Use of a high performance AGM separator for lead-acid batteries, based on the method for the production of a high performance AGM separator for lead-acid batteries according to any one of claims 3 to 4, characterized in that: The separator is used in electric vehicle batteries and communication base station backup power supplies.

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