KR102233128B1 - Manufacturing method of active material for lead acid battery containing bimetallic structured fiber - Google Patents

Abstract

The present invention relates to a method of manufacturing an active material for a lead acid battery containing a bimetallic structured fiber and, more specifically, to a method of manufacturing an active material for a lead acid battery containing a bimetallic structured fiber, comprising the following steps of: applying a composite fiber that expresses a bimetallic structure due to difference in shrinkage force between polymers during a heat treatment process by composite spinning of two types of polymers with different viscosities and shrinkage characteristics, and manufacturing a fiber having a spring structure; manufacturing an active material mixture by adding a manufactured bimetallic structured fiber to an additive mixture; and applying the manufactured active material mixture to a substrate made of lead. Therefore, it is possible to improve mechanical strength and fiber electrolyte moisture content of a lead acid battery to increase a surface area between an active material and sulfuric acid that is an electrolyte solution, thereby improving durability and basic performance.

Description

Manufacturing method of active material for lead acid battery containing bimetallic structured fiber

The present invention relates to a method of manufacturing an active material for a lead acid battery to which a bimetallic fiber is added, and more particularly, a bimetallic structure due to a difference in shrinkage force between each polymer during a heat treatment process by complex spinning two types of polymers having different viscosity and shrinkage properties. The mechanical strength of lead acid battery is applied to a substrate made of lead by applying a composite fiber expressing A and preparing a fiber having a spring structure, and then adding the prepared bimetal structure fiber to an additive mixture to prepare an active material mixture and apply it to a substrate made of lead. And a method of manufacturing an active material for a lead-acid battery in which a bimetallic fiber capable of improving durability and basic performance by increasing a surface area between an active material and sulfuric acid, which is an electrolyte, by improving a fiber electrolyte moisture content.

The current lead acid battery active material mechanism is adding polyester-based fibers to the active material to secure physical strength and a reaction surface area with sulfuric acid.

Typically, polyester-based fibers having a fineness of 2 to 5 denier and a length of 1 to 10 mm are added to the lead acid battery active material, and these fibers (fibers) have excellent acid resistance and oxidation resistance.

At this time, the added short organic synthetic fibers generally have a circular cross-sectional shape, and the length is about 2 to 10 mm.

The components of organic synthetic staple fibers are mainly made of polypropylene, polyester, and modacrylic, which have excellent acid resistance and oxidation resistance.

In the related art of Korean Patent Registration No. 10-0603908, "electrode plate for storage battery and its manufacturing method", the electrode plate is manufactured by attaching fiber-reinforced paper by applying pressure so that the fiber filaments are stuck on the surface of the active material and filling the active material in the irregularities of the surface. Initiate the method.

The above-described conventional Korean registered patent relates to "electrode plate for storage battery and its manufacturing method". The electrode plate of the storage battery is coated with an active material having an electrochemical activity on a substrate serving as a passage through which electricity flows, and fiber-reinforced paper is applied to the surface of the active material. In the step of attaching or pressing, pressure is applied so that the fibrous filaments of the fibrous reinforced paper are stuck to a certain depth, and the active material is filled in the surface irregularities of the fibrous reinforced paper to increase the binding surface area, thereby preventing the active material from detaching from the substrate. In addition, technology that improves the initial high rate discharge characteristics of the electrode plate due to the porosity of the fiber-reinforced paper, and also extends the life of the battery by holding and supporting the active material due to the stable support and acid resistance of the fibrous filament structure of the fiber-reinforced paper. It is about.

Until now, lead (Pb)-calcium (Ca)-tin (Sn)-based alloys have been used as grid alloys for lead-acid batteries, but this alloy composition alone cannot adequately cope with the harsh environment (high temperature and overcharging phenomenon), so the grid is corroded or corroded. It has been pointed out as a problem that the life of the lead acid battery is shortened due to deformation caused by the growth of the battery.

Accordingly, it is required to improve the corrosion resistance and mechanical strength of the grid and to suppress the growth deformation.

On the other hand, the active material of a conventional lead acid battery is generally based on lead powder and an aqueous sulfuric acid solution, and other additives are mixed according to the characteristics of the positive electrode and the negative electrode, and then mixed to make an active material.

The active material thus made is applied to the substrate, undergoes a aging process and a drying process according to the characteristics of the positive and negative electrodes, and then alternately overlaps the prepared positive and negative plates, and at this time, to prevent an electrical short between the electrode plates. For this purpose, a non-conductive separator is installed, and a positive electrode plate, a negative electrode plate, and a separator are configured to form an electrode plate group.

According to the capacity of the storage battery, several electrode plate groups are connected in series and are accommodated in the roll box.

The accommodated electrode plate group undergoes a conversion process, which is supercharged so as to have electrical properties.At this time, lead dioxide (PbO2) is formed as the active material of the positive electrode plate, and due to its characteristics, numerous particles of oxidized lead are combined and the porosity is abundant. The electrolyte is freely diffused and penetrated into the liver.

In addition, the active material of the negative electrode plate is sea surface lead (Pb), which is also rich in porosity and reactivity, so that the electrolyte can freely diffuse and penetrate.

The product made in this way can be used in the market.

In addition, in order to facilitate the supercharge process and improve the durability of the product, separate aging and drying processes are performed for each polarity.

The aging process of the positive electrode plate is an important process to increase the durability of the product, and lead (Pb), a constituent of the active material, is converted into lead (Pb) as a component of the active material at the hot temperature (about 70 ~ 100℃) and moisture (humidity 99%) of PbO), but also changes the crystal structure of the active material.

The negative electrode plate can be aged and dried at the same time if it is left in its natural state without any separate process.

However, if sufficient aging and drying are not performed, the electrode plate and the electrode plate adhere to each other in the assembly process of forming the electrode plate group, and the durability of the active material decreases due to the presence of moisture, so that the active material embedded between the substrates easily falls even under a small impact.

As the number of times of charge and discharge increases, the active material falls more easily from the substrate by the reaction of lead and sulfuric acid, and the fallen active materials can no longer participate in the reaction. By degrading the performance, the life of the lead acid battery is usually only 1 to 2 years.

Accordingly, there is a demand for a manufacturing process capable of improving the durability and performance of the lead storage battery.

As a conventional technique, the'cathode active material and its manufacturing method and lead acid battery' has disclosed a technique related to a negative electrode active material, characterized in that lignin is added to lead powder.

However, it was difficult to expect the above technology to have an effect of improving the life of the active material.

Meanwhile, the recent lead acid battery industry is striving to develop a battery for a micro-hybrid or mild-hybrid vehicle in an environment with a high depth of charge and discharge. In order to improve durability, the development of an active material having a higher reaction area with sulfuric acid has been required, and the present invention has been proposed to solve this problem.

Korean Patent Registration No. 10-0483246

Therefore, the present invention was devised to solve the above conventional problems,

A composite fiber that expresses a bimetallic structure due to the difference in contraction force between each polymer during the heat treatment process by composite spinning two kinds of polymers with different viscosity and shrinkage characteristics, and after manufacturing a fiber having a spring structure, the manufactured bimetallic structure By adding fiber to the additive mixture to prepare an active material mixture and applying it to a substrate made of lead, the mechanical strength of the lead acid battery and the moisture content of the fiber electrolyte are improved, thereby increasing the surface area between the active material and the electrolyte, sulfuric acid, to increase durability and basic performance. An object of the present invention is to provide a method of manufacturing an active material for a lead acid battery to which an improved bimetallic fiber is added.

In order to achieve the problem to be solved by the present invention, a method of manufacturing an active material for a lead acid battery to which a bimetallic fiber is added according to an embodiment of the present invention,

Bimetal structured fiber manufacturing step of producing a fiber having a spring structure by applying a composite fiber that expresses a bimetal structure due to the difference in contraction force between each polymer during the heat treatment process by compound spinning two types of polymers with different viscosity and shrinkage properties ( S100); and

The bimetallic structured fiber additive active material mixture manufacturing step (S200) for preparing an active material mixture by adding the prepared bimetallic structured fiber to the additive mixture; And

After applying the prepared mixture to a substrate made of lead, the active material application step (S300) of naturally aging and drying in the air for 2 to 3 days; by including, solving the problem for improving the durability and basic performance of the lead storage battery It is done.

Through the method of manufacturing an active material for a lead acid battery with bimetallic structure fiber added according to the present invention, two kinds of polymers having different viscosity and shrinkage properties are combined and spun to develop a composite fiber that expresses a bimetallic structure due to the difference in shrinkage force between each polymer during the heat treatment process. After applying and manufacturing a fiber having a spring structure, an active material mixture is prepared by adding the prepared bimetallic fiber to the additive mixture, and then applied to a substrate made of lead, thereby improving the mechanical strength and moisture content of the fiber electrolyte. By improving the surface area between the active material and sulfuric acid, which is an electrolyte, it provides an effect of improving durability and basic performance.

1 is a flowchart of a method of manufacturing an active material for a lead acid battery to which a bimetallic fiber is added according to an embodiment of the present invention.
Figure 2 shows the difference in shrinkage between polytrimethylene terephthalate (PTT) and polyethylene terephthalate (PET) when performing the heat treatment process of the method for manufacturing an active material for a lead-acid battery in which bimetallic fiber is added according to an embodiment of the present invention. It is an exemplary diagram shown.
3 is a photograph showing a bimetallic fiber before and after heat shrinkage in a method of manufacturing an active material for a lead acid battery to which a bimetallic fiber is added according to an embodiment of the present invention.
4 is a graph comparing the improved product and the conventional product manufactured in the method for manufacturing an active material for a lead acid battery containing bimetallic fiber according to an embodiment according to an embodiment of the present invention, in a high-temperature environment according to the standards of the American Automobile Engineers Association It is a graph drawing verifying the service life in.
FIG. 5 is a graph comparing an improved product and a conventional product manufactured in the method for manufacturing an active material for a lead-acid battery in which a bimetal structure fiber is added according to an exemplary embodiment according to an exemplary embodiment of the present invention. FIG.

A method of manufacturing an active material for a lead acid battery to which a bimetallic fiber is added according to an embodiment of the present invention,

Bimetal structured fiber manufacturing step of producing a fiber having a spring structure by applying a composite fiber that expresses a bimetal structure due to the difference in contraction force between each polymer during the heat treatment process by compound spinning two types of polymers with different viscosity and shrinkage properties ( S100); and

The bimetallic structured fiber additive active material mixture manufacturing step (S200) for preparing an active material mixture by adding the prepared bimetallic structured fiber to the additive mixture; And

And applying the prepared mixture to a substrate made of lead, and then applying an active material (S300) of naturally aging and drying in the air for 2 to 3 days.

At this time, the two kinds of polymers,

It is characterized in that it is polytrimethylene terephthalate (PTT) and polyethylene terephthalate (PET).

At this time, the bimetallic structure fiber,

It is characterized in that it increases the surface area between the active material and sulfuric acid, which is an electrolyte, by improving the moisture content of the fiber electrolyte.

At this time, by the method of manufacturing an active material for a lead acid battery to which the bimetallic fiber is added,

When the manufactured lead acid battery has a capacity of 80Ah ~ 87Ah,

The lifetime is characterized by being able to provide durability improvement within the range of 20% to 25% from 2,304 to 2,400 cycles at 1,920 cycles.

At this time, by providing a lead-acid battery containing an active material for a lead-acid battery to which bimetallic fiber is added by the manufacturing method of the present invention, the mechanical strength of the lead-acid battery and the moisture content of the fiber electrolyte are improved, and thus the active material and the electrolyte are mixed with sulfuric acid. By increasing the surface area, it provides the effect of improving durability and basic performance.

Hereinafter, it will be described in detail through examples of a method for manufacturing an active material for a lead acid battery to which a bimetallic fiber is added according to the present invention.

1 is a flowchart of a method of manufacturing an active material for a lead acid battery to which a bimetallic fiber is added according to an embodiment of the present invention.

As shown in Fig. 1, the method of manufacturing an active material for a lead acid battery to which a bimetallic fiber of the present invention is added,

Bimetal structured fiber manufacturing step of producing a fiber having a spring structure by applying a composite fiber that expresses a bimetal structure due to the difference in contraction force between each polymer during the heat treatment process by compound spinning two types of polymers with different viscosity and shrinkage properties ( S100); and

The bimetallic structured fiber additive active material mixture manufacturing step (S200) for preparing an active material mixture by adding the prepared bimetallic structured fiber to the additive mixture; And

After applying the prepared mixture to a substrate made of lead, the active material application step (S300) of naturally aging and drying in the air for 2 to 3 days.

The present invention applies a composite fiber that expresses a bimetal structure due to a difference in contraction force between each polymer during a heat treatment process by composite spinning two types of polymers having different viscosity and shrinkage properties, and then manufacturing a fiber having a spring structure. The resulting bimetallic fiber is added to the additive mixture to prepare an active material mixture and applied to a substrate made of lead, thereby improving the mechanical strength of the lead acid battery and the moisture content of the fiber electrolyte, increasing the surface area of the active material and the electrolyte, sulfuric acid, for durability and durability. It is to provide an effect of improving basic performance.

Conventional lithium ion batteries have used a binder such as PVdF (organic) centered on pre-bonding or CMC (aqueous system) centered on point binding due to high molecular weight in order to increase the bonding force between active materials.

However, manufacturers of lead-acid batteries are currently using polyester-based fiber rather than a powder-type material to increase the bonding strength between active materials.

In the case of polyester-based fiber, it was difficult to expect improved durability and performance because it does not have conductivity.

On the other hand, the present invention not only improves the mechanical strength of the active material, but also provides a fiber that exhibits a bimetallic structure instead of improving the conductivity, thereby further increasing the moisture content of the fiber electrolyte, thereby increasing the surface area of the active material and the electrolyte, sulfuric acid. It is to improve the basic performance of the storage battery.

As a result, it was confirmed through an experiment that the efficiency of the negative electrode active material can be improved and the charging acceptance can be improved.

Specifically, a composite fiber that expresses a bimetal structure due to the difference in shrinkage force between each polymer during the heat treatment process by composite spinning two kinds of polymers having different viscosity and shrinkage characteristics, and manufacturing a fiber having a spring structure After that, by adding the prepared bimetallic fiber to the additive mixture to prepare an active material mixture and applying it to a substrate made of lead, it is possible to improve basic performance by more than 5% and improve durability by 25% compared to a conventional lead acid battery. After discovery, verification tests, and completion of the present invention.

Next, the manufacturing steps will be described in detail.

In the bimetallic structured fiber manufacturing step (S100), a composite fiber expressing a bimetallic structure due to a difference in contraction force between each polymer during a heat treatment process by composite spinning two kinds of polymers having different viscosity and shrinkage properties, and having a spring structure This is the process of manufacturing fibers.

Specifically, when the difference in viscosity between the two polymers is large, the reason for exhibiting excellent elasticity is that it exhibits elasticity based on the crimp expressed by the difference in thermal properties such as thermal stress and thermal contraction rate of the two polymers. The more the difference in the thermal properties of the type of polymer is maximized, the better the fiber produced has excellent elasticity.

At this time, the two kinds of polymers are characterized in that polytrimethylene terephthalate (PTT) and polyethylene terephthalate (PET).

In other words, when a fiber is manufactured using polytrimethylene terephthalate having excellent elasticity and polyethylene terephthalate having a low viscosity due to its high viscosity and a helical molecular chain shape than the case of using only polyethylene terephthalate as two types of polymers. It is advantageous for expressing a high degree of elasticity, and when the heat treatment process is performed, a bimetallic structure is expressed by the difference in contraction force between each polymer, so that a spring structure can be made (see Fig. 2).

At this time, the preferred viscosity of each polymer is 0.40 to 0.65 dl/g for polyethylene terephthalate, 10 to 15 dl/g for polytrimethylene terephthalate, and the viscosity difference between the two polymers is maintained at a level of 0.5 to 1.1 dl/g. It is preferable in the stretch characteristics and the complex spinning process.

If the difference in viscosity is less than 0.5 dl/g, it is difficult to expect a high elasticity property, and if it exceeds 1.1 dl/g, there is a problem that the spinning performance is deteriorated.

In addition, the melting temperature of the polymer is preferably about 285 to 300°C for PET and 255 to 275°C for PTT, and about 250 to 290°C for the spinning temperature, but considering the complex spinning process and the thermal decomposition of PTT, it is preferable. It should be in the range of 270 ~ 290℃.

In this case, since the composite spinning device and the operating principle are generally used composite spinning devices, it may be sufficiently implemented at the level of a person skilled in the art without having to describe them in detail.

Further, the fiber of the present invention is directly spin-drawn to obtain a fiber having a spring structure to which a spring-shaped crimp is applied.

The spin-draw of the present invention is performed using a conventional direct spinning device, and does not require a special device such as a heater.

In addition to the first step of spinning direct drawing, a two step process of spinning-drawing is also possible, but considering the simplification of the process, manufacturing cost, and changes in physical properties over time of PTT fiber, it is preferable to use the first step of spinning direct drawing.

In the case of spinning direct stretching, a cold air temperature of 20℃ and a cold air speed of about 0.4 to 0.5m/sec are appropriate, and the first godet controller is set at a speed of 800 to 1,200m/min, and a temperature of 60 to 90℃, and the second godet controller It is preferable to set the speed at a speed of 3,000 to 4,500 m/min, and a temperature of 120 to 180°C.

In general, polyethylene terephthalate is also commonly referred to as PET.

To obtain PET, dimethyl terephthalate and ethylene glycol are heated at 150 to 230°C to obtain Bis(β-hydroxyethyl) terephthalate through transesterification.

When Bis(β-hydroxyethyl) terephthalate is heated to 270 ~ 300℃ under 1 torr, polycondensation occurs and ethylene glycol is released to obtain PET.

Another way to obtain Bis(β-hydroxyethyl) terephthalate is to react with high purity terephthalic acid and ethylene glycol at about 230°C while applying pressure.

It is excellent in heat resistance, rigidity, and electrical properties, and the ultimate strength decreases only slightly even at high temperatures for a long time.

Because it belongs to crystalline plastic, it has good resistance to oil such as diesel oil.

However, since there is an ester bond in the molecular chain, it is easy to change when the molded product is immersed in an acid or alkali over a long period of time at a high temperature.

Since crystallization is slow, it is not suitable for injection molding.

Therefore, a method such as adding a nucleating agent or making crystals is used. In order to use it as an engineering plastic, the use of glass fiber reinforced PET improves mechanical strength and dimensional stability.

Reinforced PET has excellent heat resistance among thermoplastic resins, has excellent fatigue strength and electrical properties, and is less affected by temperature and humidity. It is widely used as a raw material for synthetic fibers and films.

Polyethylene terephthalate (PET) having the above characteristics is combined with polytrimethylene terephthalate (PTT) during a heat treatment process to express a bimetallic structure by a difference in shrinkage force between each polymer.

Therefore, when this is added to the active material and applied to the substrate, it is used to further increase the moisture content of the fiber electrolyte and increase the surface area between the active material and sulfuric acid, which is an electrolyte.

Thereafter, the bimetallic structured fiber-added active material mixture manufacturing step (S200) is a process for preparing an active material mixture by adding the prepared bimetallic structured fiber to the additive mixture.

In general, an active material mixture is prepared by additionally adding the bimetallic fiber prepared in the above step to an additive mixture added when preparing a negative active material.

At this time, preferably the content of the bimetallic structure fiber,

It is characterized in that the addition of 2 ~ 10 wt% compared to the content of the lead.

As the content of the bimetallic fiber increases, the modulus of elasticity and the tensile modulus increase, and when additionally added to the negative electrode plate, the moisture content of the electrolyte solution can be improved.

However, when the content exceeds the set amount, it is difficult to form the product due to the high tensile modulus, and when the content is less than the set content, it is preferable to add it within the above-described content range because it has the same level of elasticity and tensile modulus as the non-added content. will be.

Thereafter, the active material application step (S300) is a process of applying the prepared mixture to a substrate made of lead, and then naturally aging and drying in the air for 2 to 3 days.

That is, after a certain amount of the negative active material including the bimetallic fiber is spread evenly on a substrate made of lead, it is naturally aged and dried in the air for 2 to 3 days, specifically, the anode active material including the bimetallic fiber After going through the application work, which is a work applied to the silver substrate, and after going through the aging process and drying process according to the characteristics of the positive and negative electrodes, the prepared positive and negative plates are alternately overlapped, and at this time, in order to prevent an electrical short between the electrode plates, non-conductive By installing a separator, a positive electrode plate, a negative electrode plate, and a separator are configured to form an electrode plate group, and several electrode plate groups are connected in series according to the capacity of the storage battery to be accommodated in the roll tank.

In general, short organic synthetic fibers added to the negative electrode active material are added to the active material for the purpose of increasing the mechanical strength of the battery active material.

As the material, polypropylene, polyester, and modacrylic are used in consideration of acid resistance to an aqueous sulfuric acid solution, which is an electrolyte.

The organic synthetic short fiber used has a circular cross section, which is the specification of a conventional synthetic short fiber manufactured by direct spinning, has a fineness of 2 to 5 denier (diameter is about 12 to 20 micrometers), and the length is 2 to It is 10 millimeters.

The amount added during mixing is 0.1 ~ 0.5 wt%, thereby improving the mechanical strength of the final electrode active material, thereby suppressing the destruction of the active material structure due to contraction and expansion of the active material due to vibration and charge/discharge.

However, in order to improve the basic performance and durability of the battery in the micro-hybrid or mild-hybrid vehicle currently being manufactured in an environment with a high depth of charge and discharge, the bimetallic fiber is used in the present invention. In addition to improving the mechanical strength of the active material through this, as well as providing a spring structure, it provides superior elasticity, elasticity, and surface area than before, thereby further increasing the moisture content of the fiber electrolyte. It is to improve the basic performance of lead acid batteries by increasing the surface area of phosphorus sulfuric acid.

That is, by providing the expansion of the reaction area with sulfuric acid, the basic performance and durability of the battery are improved.

As described above, in order to understand the effects of the present invention, in general, after applying the negative electrode active material, the lead acid battery combined with the electrode plate and the strap and the negative electrode active material containing 10 wt% of the bimetallic fiber of the present invention were applied, and then the electrode plate and the strip were applied. The basic performance and life test of the lead-acid battery combined with rab was conducted, but a product with a final capacity of 80Ah was produced through subsequent processes such as assembling and hwaseong, and according to SAE J240 standard to verify the lifespan at high temperatures. The life test was carried out accordingly.

The conventional product to be described later refers to a lead acid battery in which an electrode plate and a strap are combined after applying the active material used in the lead acid battery manufactured by the applicant, and the improved product is the electrode plate and the electrode plate after applying the negative electrode active material to which the bimetal structure fiber is added. It refers to a lead acid battery combined with a strap.

As a result of the test, the capacity and lifespan of 87Ah in the holding capacity ended at 2,400 cycles, which was improved by 6% in the holding capacity and 25% in the lifespan compared to the conventional product.

Experimental data on this will be described later.

4 is a graph comparing the improved product and the conventional product manufactured in the method for manufacturing an active material for a lead acid battery containing bimetallic fiber according to an embodiment according to an embodiment of the present invention, in a high-temperature environment according to the standards of the American Automobile Engineers Association It is a graph drawing verifying the service life in.

The test standard is a test method for measuring the cycle until the end of the life of the lead acid battery by repeating charging/discharging at a high temperature (75°C).

(1 cycle: 25A 4 minutes discharge, 14.8V [max 25A] constant voltage 10 minutes charge)

This test is repeated 480 times for 1 week, and then after standing for 56 hours, the state of the lead acid battery is determined by discharging at a high rate of 630A and measuring the voltage at the time point of 30 seconds.

If the voltage at the time of 30 seconds is more than 7.2V, the lead acid battery is judged as intact and the above cycle is repeated. If it is less than 7.2V, the lead acid battery is judged as the end of its life and the test is stopped.

<Test Example>

The conventional product to be described later refers to a lead acid battery in which an electrode plate and a strap are combined after applying the active material used in the lead acid battery manufactured by the applicant. It refers to a lead acid battery combined with a strap.

division Conventional product Improvement RC 118min 125min CCA 622A 640A C20 82Ah 87Ah Durability (SAE J240) 1,920 Cycle) 2,400 Cycle

Table 1 is a performance test result of a conventional lead acid battery and a lead acid battery manufactured using the manufacturing method of the present invention, showing 1,920 cycles in the case of the conventional product with durability, and 2,400 cycles in the case of the improved product. See Fig. 4)

Therefore, it was confirmed through an experiment that the improved product has 25% improvement in durability than the conventional product.

1) Reserve Capacity (RC)

Retention capacity RC measures the duration of discharge possible until the discharge end voltage reaches 10.5V with a discharge current of 25A at 25℃ after leaving for 1 hour or more after completion of full charge. It is a measure of how long the minimum function can be exerted to operate the load in a stopped state, etc.

As a result of the test, as shown in Table 1, when prepared by applying the negative electrode active material to which the bimetallic fiber according to the present invention is added, the holding capacity (RC) is 126 to 130 minutes, and is precisely 125 minutes, compared to the existing conventional products. In contrast, by showing a 6% performance improvement effect, it was found that the anode active material for lead-acid batteries to which the bimetallic fiber was applied had a positive effect on the holding capacity.

2) Low temperature starting current (CCA: Cold Cranking Ampere)

In general, the rapid discharge characteristics of a storage battery rapidly deteriorate below -10℃. The low-temperature starting current (CCA) is a high-rate discharge test for evaluating the starting ability of a vehicle at low temperatures. Measure the voltage at the time of super discharge.

In this test, the voltage at 30 seconds is required to be more than 7.2V, and the higher it is, the better the performance is evaluated.

In the present invention, the CCA was calculated using a correction formula of (30 second voltage ÷ 6-0.2) × 630.

As a result of the test, as shown in Table 1, the voltage for 30 seconds is 7.15V ~ 7.22V, and the converted CCA is 650A ~ 660A, and it is precisely 640A, showing a 4% performance improvement effect compared to the conventional product. It was found that the negative active material for lead-acid batteries to which is applied had a positive effect on the low-temperature starting current.

3) 20 hour rate capacity (AH)

This is to find out the low rate discharge characteristics, by continuously discharging at 3.75A, which is a relatively small current relative to the capacity of the lead acid battery, and measuring the discharge capacity (AH) until the voltage reaches 10.5V.

As a result of the test, 85AH ~ 89AH, precisely 87AH, showed a 6% performance improvement effect compared to the existing products, so that the active material for lead-acid batteries applied with bimetallic fiber had a positive effect on the 20-hour rate capacity (AH). I could see that I gave it.

4) Life verification test (SAE J240, Cycle)

As a graph (SAE J240) that verified the lifespan in a 75°C environment according to the standards of the American Association of Automobile Engineers, the test standard indicates the cycle until the end of the life of the lead acid battery by repeating charging/discharging at high temperature (75°C) It is a test method to measure.

(1 cycle: 25A 4 minutes discharge, 14.8V [max 25A] constant voltage 10 minutes charge)

This test is repeated 480 times for 1 week. After that, after standing for 56 hours, discharge at a high rate of 630A and measure the voltage at the time point of 30 seconds to determine the state of the lead acid battery.

If the voltage at the time of 30 seconds is more than 7.2V, the lead acid battery is judged as intact and the above cycle is repeated. If it is less than 7.2V, the lead acid battery is judged as the end of its life and the test is stopped.

As a result of the test, as shown in FIG. 2, it was found that the active material for a lead-acid battery to which the bimetallic fiber was applied had a positive effect on the lifespan by showing a 25% improvement in the lifespan compared to the conventional product.

5) Charge acceptance test (CA: Charge Acceptance test)

After discharging the fully charged sample for 2.5 hours at room temperature (25±2℃) with a 5-hour rate current (17.5A based on 70Ah), leave it for 12 hours or more at 0±2℃.

After that, it is charged with a constant voltage of 14.4V±0.1V and the current is measured for 10 minutes of charging.

As a result of the test, it was found that the electric conductivity and charging efficiency were high, and the current of the improved product increased by 32% in about 10 minutes compared to the conventional product (see FIG. 5).

division time Conventional product Improvement




Rechargeable income 1 min 27.25 28.17 2 minutes 24.21 26.98 3 minutes 22.14 26.22 4 minutes 21.25 25.52 5 minutes 20.11 24.83 6 minutes 19.35 23.94 7 minutes 18.74 23.46 8 minutes 17.68 22.79 9 minutes 17.04 22.37 10 minutes 16.43 21.78

Through the manufacturing method as described above, a composite fiber that expresses a bimetal structure due to the difference in contraction force between each polymer during the heat treatment process by compound spinning two types of polymers having different viscosity and shrinkage characteristics, and a fiber having a spring structure After manufacture, the prepared bimetallic fiber is added to the additive mixture to prepare an active material mixture and applied to a substrate made of lead, thereby improving the mechanical strength of the lead acid battery and the moisture content of the fiber electrolyte. By increasing the surface area, it provides the effect of improving durability and basic performance.

Those skilled in the art to which the present invention with the above contents pertains will be able to understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, the embodiments described above are exemplified in all respects and should be understood as non-limiting.

S100: Bimetal structured fiber manufacturing stage
S200: Bimetallic structured fiber additive active material mixture manufacturing step
S300: Active material application step

Claims (5)

In the method for producing an active material for a lead acid battery to which bimetallic fiber is added,
Bimetal structured fiber manufacturing step of producing a fiber having a spring structure by applying a composite fiber that expresses a bimetal structure due to the difference in contraction force between each polymer during the heat treatment process by compound spinning two types of polymers with different viscosity and shrinkage properties ( S100); and
A bimetallic structured fiber additive active material mixture manufacturing step (S200) for preparing an active material mixture by adding the prepared bimetallic structured fiber to the additive mixture; And
After applying the prepared mixture to a substrate made of lead, the active material application step (S300) of naturally aging and drying in the air for 2 to 3 days; including,
The two kinds of polymers,
It is characterized in that it is polytrimethylene terephthalate (PTT) and polyethylene terephthalate (PET),
The bimetallic structure fiber,
It is characterized by improving the moisture content of the fiber electrolyte to increase the surface area of the active material and the electrolyte, sulfuric acid.
In the case of polyethylene terephthalate, the viscosity is 0.40 to 0.65 dl/g, and in the case of polytrimethylene terephthalate, the viscosity is 10 to 15 dl/g, and the viscosity difference between the two polymers is maintained at a level of 0.5 to 1.1 dl/g. And
Polytrimethylene terephthalate (PTT) has a melting temperature of 255 to 275°C, polyethylene terephthalate (PET) has a melting temperature of 285 to 300°C, and a spinning temperature of 270 to 290°C.
The content of the bimetallic structure fiber,
It is characterized by adding 2 to 10 wt% relative to the content of lead,
By the method for producing an active material for a lead acid battery to which the bimetallic fiber is added,
When the manufactured lead acid battery has a capacity of 80Ah ~ 87Ah,
The lifetime is characterized by being able to provide durability improvement within the range of 20% to 25% from 2,304 to 2,400 cycles at 1,920 cycles,
The holding capacity (RC) is improved from 118 minutes to 126 ~ 130 minutes,
Low temperature starting current (CCA) is improved from 622A to 650A ~ 660A,
20 hour rate capacity (AH) improves from 82Ah to 85AH to 89AH,
A method of manufacturing an active material for a lead-acid battery with the addition of bimetallic fiber, characterized in that the rechargeable income (CA) is improved from 16.43 to 21.78. delete delete delete delete

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