KR102483444B1 - method for manufacturing a negative electrode plate of a lead acid battery that increases the surface area between the electrolyte and the active material by applying expanded perlite - Google Patents

Abstract

The present invention relates to a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite, and more particularly, by adding expanded perlite to an active material added to a conventional lead-acid battery negative electrode to improve electrolyte permeability in the electrode plate. And a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite, which can improve the basic performance and charging efficiency of a lead-acid battery by increasing the internal electrical conductivity of the negative electrode active material by increasing the binding force of the active material and expanding the reaction area. It relates to a method for manufacturing a negative electrode plate.
Through the present invention, the addition of expanded perlite provides an effect of increasing the basic performance and charging efficiency of a lead-acid battery by increasing the pore activation and reaction area with sulfuric acid and increasing the internal electrical conductivity of the negative electrode active material.

Description

Method for manufacturing a negative electrode plate of a lead acid battery that increases the surface area between the electrolyte and the active material by applying expanded perlite}

The present invention relates to a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite, and more particularly, by adding expanded perlite to an active material added to a conventional lead-acid battery negative electrode to improve electrolyte permeability in the electrode plate. And a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite, which can improve the basic performance and charging efficiency of a lead-acid battery by increasing the internal electrical conductivity of the negative electrode active material by increasing the binding force of the active material and expanding the reaction area. It relates to a method for manufacturing a negative electrode plate.

Currently, lead-acid battery active material mechanisms are adding polyester-based fibers to the active material to secure physical strength and surface area for reaction with sulfuric acid.

Typically, polyester-based fibers having a fineness of 0.8 to 5 denier and a length of 1 to 10 mm are added to lead-acid battery active materials, and these fibers (fibers) have excellent acid resistance and oxidation resistance.

At this time, the added organic synthetic short fibers usually have a circular cross-section and have a length of about 2 to 10 mm.

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

Prior art, Korean Patent Registration No. 10-0603908, “Electric plate for storage battery and its manufacturing method” is an electrode plate manufactured by attaching fiber-reinforced paper by applying pressure so that fiber filaments are embedded on the surface of the active material and filling the concave-convex part of the surface with active material start the way

The above-mentioned prior Korean registered patent relates to "a electrode plate for a storage battery and a method for manufacturing the same," wherein an active material having electrochemical activity is applied to 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 compressing, the fiber filaments of the fiber-reinforced paper are attached by applying pressure so that the fiber filaments of the fiber-reinforced paper are embedded to a certain depth, and the active material is filled in the surface irregularities of the fiber-reinforced paper to increase the binding surface area, thereby preventing the active material from being detached from the substrate technology to extend the life of the storage battery by improving the initial high-rate discharge characteristics of the electrode plate due to the porosity of the fiber-reinforced paper and by holding and supporting the active material due to the stable bearing capacity and acid resistance of the fiber-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. It has been pointed out as a problem that deformation due to the growth of the lead-acid battery is shortened.

Accordingly, corrosion resistance of the grid, improvement in mechanical strength, and suppression of growth deformation are required.

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

The active material thus prepared goes through a coating operation, which is a work of applying it to a substrate, and then undergoes an aging process and a drying process according to the characteristics of the anode/cathode, and then several sheets of the prepared positive and negative plates are alternately overlapped. In order to do this, a non-conductive separator is installed, and the positive electrode plate, the negative electrode plate, and the separator plate are configured to form a group of electrode plates.

A number of electrode plate groups are connected in series according to the capacity of the storage battery and accommodated in the electric battery.

The accommodated electrode group undergoes a supercharged chemical formation process so that it can 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 fine particles of oxidized lead are combined, and the porosity is rich, so that the particles The electrolyte is designed to freely diffuse and permeate the liver.

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

Products made in this way are finally available on the market.

In addition, in order to facilitate the supercharging 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 component of the active material, is converted into lead oxide ( PbO), as well as changing the crystal structure of the active material.

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

However, if sufficient aging and drying are not performed, electrode plates stick to each other during 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 with a small impact.

In a lead-acid battery made through this process, as the number of charge and discharge increases, the active material is more easily separated from the substrate by the reaction between lead and sulfuric acid, and the fallen active material can no longer participate in the reaction. By degrading the performance, the lifespan of lead-acid batteries is usually only 1 to 2 years.

Accordingly, there is a demand for a manufacturing process capable of improving durability and performance of lead-acid batteries in line with the current demand for high-performance lead-acid batteries.

As a prior art, 'negative electrode active material and its manufacturing method and lead-acid battery' has disclosed a technology related to an anode active material characterized in that lignin is added to lead powder.

However, it is difficult to expect an effect of improving the lifespan of the active material in the above technique.

Korean Patent Registration No. 10-0483246

Therefore, the present invention has been made to solve the above conventional problems,

An object of the present invention is to add expanded perlite to the active material added to the conventional lead-acid battery negative electrode to improve electrolyte permeability in the electrode plate, increase the active material binding force, and expand the reaction area, thereby increasing the internal electrical conductivity of the negative electrode active material to lead-acid battery It is intended to provide a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between an electrolyte and an active material is increased by applying expanded perlite capable of improving basic performance and charging efficiency.

In order to achieve the problem to be solved by the present invention, a method for manufacturing a negative electrode plate of a lead acid battery in which the surface area between the electrolyte and the active material is increased by applying the expanded perlite according to an embodiment of the present invention,

In the process of mixing negative electrode active materials of lead-acid batteries,

When mixing lead, sulfuric acid, and additives according to the negative electrode, expanded perlite mixing step (S100) to add and mix expanded perlite powder to distribute in the negative electrode active material; and

A natural aging and drying step (S200) for applying the negative electrode active material containing expanded perlite to a substrate made of lead and then naturally aging and drying it in the air (S200), thereby solving the problem of the present invention.

Through the method of manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying the expanded perlite of the present invention, the expanded perlite is added to the active material added to the negative electrode of the lead-acid battery to improve the permeability of the electrolyte solution in the electrode plate, increase the binding force of the active material, and increase the reaction area By being able to expand, it is provided to improve the basic performance and charging efficiency of the lead-acid battery by increasing the internal electrical conductivity of the negative electrode active material.

Specifically, by adding expanded perlite, pores are activated, the reaction area with sulfuric acid is increased, and the internal electrical conductivity of the negative electrode active material is increased, thereby providing effects of increasing basic performance and charging efficiency of the lead-acid battery.

1 is a process diagram of a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between an electrolyte and an active material is increased by applying expanded perlite according to an embodiment of the present invention.
2 is a photograph showing the expanded perlite included in the present invention.

A method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite according to an embodiment of the present invention,

In the process of mixing negative electrode active materials of lead-acid batteries,

When mixing lead, sulfuric acid, and additives according to the negative electrode, expanded perlite mixing step (S100) to add and mix expanded perlite powder to distribute in the negative electrode active material; and

A natural aging and drying step (S200) for applying the negative electrode active material containing expanded perlite to a substrate made of lead and then naturally aging and drying it in the air (S200).

At this time, the content of the expanded perlite in the negative electrode active material,

It is characterized by adding 3 to 10 parts by weight based on 100 parts by weight of the negative electrode active material excluding expanded perlite.

And, the powder size of the expanded perlite is characterized in that 1 ~ 300um.

At this time, in the expanded perlite mixing step (S100),

It is characterized in that the basic performance and charging efficiency of the lead-acid battery are increased by adding expanded perlite powder to increase the pore activation, reaction area with sulfuric acid, and internal electrical conductivity of the negative electrode active material.

At this time, by the method of manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying the expanded perlite,

It is characterized in that it can provide a lifespan improvement of 28.5% from 238 cycles without adding expanded perlite powder to 306 cycles when expanded perlite powder is added.

At this time, by the manufacturing method of the present invention,

By providing a lead-acid battery including a negative plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite, expanded perlite is added to the active material added to the negative electrode of the lead-acid battery to improve the permeability of the electrolyte in the electrode plate and increase the binding force of the active material, By being able to expand the reaction area, it is possible to improve the basic performance and charging efficiency of the lead-acid battery by increasing the internal electrical conductivity of the negative electrode active material.

Hereinafter, a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying the expanded perlite according to the present invention will be described in detail through an embodiment.

1 is a process diagram of a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between an electrolyte and an active material is increased by applying expanded perlite according to an embodiment of the present invention.

As shown in FIG. 1, a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying the expanded perlite of the present invention,

In the process of mixing negative electrode active materials of lead-acid batteries,

When mixing lead, sulfuric acid, and additives according to the negative electrode, expanded perlite mixing step (S100) to add and mix expanded perlite powder to distribute in the negative electrode active material; and

A natural aging and drying step (S200) for applying the anode active material containing expanded perlite to a substrate made of lead and then naturally aging and drying it in the air.

The present invention relates to a method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite. It is intended to improve the basic performance and charging efficiency of lead-acid batteries.

As shown in FIG. 2, the expanded perlite described in the present invention, as magma flows into a lake or sea on the surface and is rapidly cooled, pulverizes amorphous minerals generated by concentrating volatile components to an appropriate particle size to obtain a temperature of 1,100 degrees or more. It is an ultra-light pure inorganic material rapidly heated and expanded at a high temperature. It is harmless to the human body as 70 ~ 75% of the content is SiO2. .

In the present invention, this is used as an anode active material, which is a technology that has not been applied in the lead-acid battery manufacturing field.

Therefore, since the expanded perlite has a porous property during plastic expansion, it facilitates the penetration of electrolyte into the inside of the electrode plate, thereby expanding the electrical reaction area, and improving the bonding strength of the active material compared to conventional fibers, thereby improving high power and life expectancy be able to do

That is, when the expanded perlite is added, the contact area with the electrolyte is enlarged compared to the conventional fiber according to the porous shape of the expanded perlite, and the electrolyte permeability in the electrode plate is improved and the binding force of the active material is increased. It is possible to improve the ionic conductivity and the ability to accept electrons.

As a result, it was confirmed through experiments that the efficiency of the active material can be improved and the charge acceptance can be improved.

In addition, the cause of failure of a lead-acid battery depends on the type of load and management method during use.

The main causes of failure include active material sulfation, electrode plate active material omission, anode lattice corrosion, separator breakage, and complex factors.

In particular, in the case of a product installed in a vehicle, active material sulphation is accelerated depending on operating conditions and usage load in the battlefield, and electrode plate active material is dropped, resulting in premature end of life.

Therefore, it is important to increase the reaction area of the active material of the electrode, and it is important to increase the adhesive force between the active materials by increasing the elongation rate.

In conclusion, by introducing expanded perlite, the adhesion between active materials is increased by improving ionic conductivity and elongation, thereby improving the problem of delay in sulfate formation and deactivation of active materials, which are major causes of end of life.

In order to provide the above functions, the expanded perlite mixing step (S100) of the present invention is a step for adding and mixing expanded perlite powder to distribute it in the negative electrode active material when mixing lead, sulfuric acid, and additives according to the negative electrode. to be.

In order to provide the effect of the present invention, the content of expanded perlite in the negative electrode active material,

3 to 10 parts by weight is added based on 100 parts by weight of the negative electrode active material excluding expanded perlite.

The powder size of the expanded perlite is characterized in that 1 ~ 300um.

Specifically, the expanded perlite mixing step (S100),

A basic anode active material mixing step of mixing 80 to 83 parts by weight of lead powder, 5 to 10 parts by weight of sulfuric acid, 10 to 15 parts by weight of water, and 1 to 3 parts by weight of negative electrode additives based on the total weight of the negative electrode active material; and

3 to 10 parts by weight of expanded perlite powder based on the total weight of the mixture was added to the mixture formulated in the basic anode active material mixing step, and stirred at a temperature of 55 to 75 degrees to obtain a negative electrode active material with a density of 75 to 80 g/in3. It will include; anode active material acquisition step.

When the weight of the expanded perlite powder added is less than 3 parts by weight, the ionic conductivity of the electrode plate is similar to that of the prior art, so it corresponds to a small amount from which it is difficult to expect performance improvement, and when it exceeds 10 parts by weight, as proven in the accelerated life test, It is difficult to expect more than 10 parts by weight cycle of the life cycle, and only provides a cause for price increase.

Therefore, it would be preferable to add the expanded perlite powder within the above range.

Active material sulphation described in the present invention refers to a phenomenon in which an electrode plate is crystallized with lead sulfate (PbSO ₄ ), and the electrode plate is covered with an inactive material when a lead-acid battery repeatedly charges and discharges.

The main causes include repeated use of charge and discharge for a long period of time, over-discharge, long-term discharging, too low specific gravity of the electrolyte, exposure of electrode plates due to lack of electrolyte, and impurities in the electrolyte. is mixed, when insufficient filling is repeated, and the like.

In particular, the specific surface area of the cathode active material is 3.5 to 4.0 m ² /g, whereas the specific surface area of the anode active material is 0.5 to 0.6 m ² /g, which limits contact with sulfuric acid.

Accordingly, by adding porous expanded perlite, the surface area between the electrolyte and the active material is increased.

As a result, the present invention improves the battery capacity and DoD durability of a lead-acid battery by adding porous expanded perlite to the lead-acid battery negative plate active material to improve ionic conductivity, thereby expanding the pore activation, reaction area with sulfuric acid, and ionic conductivity.

In addition, the natural aging and drying step (S200) is a step for naturally aging and drying in the air after applying the anode active material containing expanded perlite to a substrate made of lead.

That is, after a predetermined amount of the negative electrode active material including the highly conductive expanded perlite is evenly spread on a substrate made of lead, it is naturally aged and dried in the air for 2 to 3 days.

As described above, in order to grasp the effect of the present invention, when mixing the active material, the previously introduced organic synthetic short fibers were replaced with highly conductive expanded perlite, added in the same weight ratio to manufacture electrode plates, aged through an aging process, and then Performance and life tests were conducted.

The conventional product described later refers to a product manufactured by using a negative electrode plate applied after including organic synthetic short fibers in the active material used in the lead acid battery (BX80) manufactured by the applicant, and the improved product is manufactured through the manufacturing method of the present invention. It refers to a product that includes electrode plates for lead-acid batteries to which high-conductivity expanded perlite is applied.

In addition, conventional products (including organic synthetic short fibers) and improved products (including high-conductivity expanded perlite) having a final capacity of 70 Ah (20 hour rate capacity) through processes such as assembly and chemical formation that impart electrical conductivity to the substrate, which are subsequent processes, included) was produced, and a charge acceptance test and 50% DoD durability test were conducted to prove the effect of the highly conductive expanded perlite.

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

The fully charged sample is discharged for 2.5 hours at room temperature (25±2℃) with a 5-hour rate current (17.5A based on 70Ah), and then left at 0±2℃ for more than 12 hours.

Afterwards, charge with a constant voltage of 14.4V±0.1V and measure the current after 10 minutes of charging.

As a result of the test, it was found that the current of the improved product increased by 21% in about 10 minutes compared to the conventional product due to high battery conductivity and charging efficiency.

division time conventional products improvement




charging acceptance 1 minute 27.25 28.17 2 minutes 24.21 25.38 3 minutes 22.14 23.83 4 minutes 21.25 22.92 5 minutes 20.11 21.83 6 minutes 19.35 21.54 7 minutes 18.74 20.86 8 minutes 17.68 20.19 9 minutes 17.04 19.67 10 minutes 16.43 19.93

Organic synthetic short fibers are added to the active material for the purpose of increasing the mechanical strength of the battery active material.

Polypropylene, polyester, and modacrylic series are used as materials in consideration of acid resistance to an aqueous solution of sulfuric acid, which is an electrolyte.

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

The amount added during mixing is 0.1 to 0.5 wt%, which improves the mechanical strength of the final electrode active material and suppresses the destruction of the active material structure due to contraction and expansion of the active material due to vibration and charging and discharging.

However, in the case of the organic synthetic short fibers, a problem occurred in providing performance in an environment requiring increasingly higher basic performance.

Therefore, in the present invention, in order to improve this, highly conductive expanded perlite having excellent electrical conductivity is used.

As shown in FIG. 2, this highly conductive expanded perlite facilitates penetration of electrolyte into the inside of the electrode plate due to its hollow shape, thereby increasing the electrical reaction area, and increasing the reaction area between pore activation and sulfuric acid than conventional fibers, resulting in high output and It is possible to bring about an improvement in life expectancy, and finally improve the basic performance and lifespan of the battery.

Therefore, the highly conductive expanded perlite having the above characteristics is introduced in the present invention, and by using the expanded perlite as an additive to the negative electrode active material, the effect of maximizing the reaction area of the active material and increasing electrical conductivity is provided.

The experimental data for this will be described later.

2) Accelerated life test (SAE J2801)

The lead-acid battery is subjected to 34 charge/discharge cycles in a water bath at 75°C for about a week, similar to general vehicle conditions.

After 34 cycles, discharge at 200A for 10 seconds, and if it is maintained at 7.2V or more, cycle 34 times again to conduct the life test.

In addition, the test is stopped if the charging current rises more than 15A or the discharge voltage falls below 12.0V during the cycle.

Table 2 below shows the results of the SAE J2801 test and shows the voltage when discharging at 200 A for 10 seconds every 34 charge/discharge cycles.

cycle Pangpangperite 0 parts by weight 1 part by weight of expanded perlite expanded perlite
2 parts by weight 10 parts by weight of expanded perlite 11 parts by weight of expanded perlite 34 11.82 11.83 11.85 11.87 11.89 68 11.76 11.77 11.80 11.83 11.87 102 11.72 11.73 11.78 11.80 11.84 136 11.69 11.71 11.76 11.79 11.82 170 11.65 11.68 11.74 11.77 11.80 204 11.55 11.61 11.69 11.70 11.76 238 11.43 11.45 11.60 11.63 11.70 272 7.2 and below 7.2 and below 11.49 11.55 11.65 306 7.2 and below 11.50 11.55 340 7.2 and below 7.2 and below

As shown in Table 2, as a result of the test, when high conductive expanded perlite is not added and when 1 part by weight is added, the life is 238 cycles, but when 2 parts by weight is added, the life is 272 cycles, and when 10 parts by weight is added, the life is 238 cycles. was able to provide a 28.5% lifespan improvement with 306 cycles.

However, it can be seen that the lifespan does not increase further at 306 cycles even when the highly conductive expanded perlite is added in an amount exceeding 10 parts by weight. Accordingly, the most optimal range is 3 to 10 parts by weight among 1 part by weight to 10 parts by weight. It is preferable to add within the above range.

This is seen as a result of the decrease in the sulphate content accumulated in the active material while the charging efficiency is increased because the electrical conductivity between the active materials is improved, the electrical resistance is lowered, and the reaction surface area is increased.

That is, by showing a 28.5% improvement in life compared to the conventional product, it was found that the addition of highly conductive expanded perlite had a positive effect on the increase in life.

Through the above manufacturing method, by adding expanded perlite to the active material added to the negative electrode of a lead-acid battery, it is possible to improve the permeability of the electrolyte solution in the electrode plate, increase the binding force of the active material, and expand the reaction area, thereby increasing the internal electrical conductivity of the negative electrode active material and lead to lead. It provides the ability to improve the basic performance and charging efficiency of the storage battery.

Those skilled in the art to which the present invention pertains as described above will understand that it can be implemented in other specific forms without changing the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above are illustrative in all respects and should be understood as not being limiting.

S100: Expanded perlite mixing step
S200: Natural aging and drying step

Claims (5)

In the method for manufacturing a negative electrode plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite,
In the process of mixing negative electrode active materials of lead-acid batteries,
When mixing lead, sulfuric acid, and additives according to the negative electrode, expanded perlite mixing step (S100) to add and mix expanded perlite powder to distribute in the negative electrode active material; and
A natural aging and drying step (S200) for applying the negative electrode active material containing expanded perlite to a substrate made of lead and then naturally aging and drying it in the air;
The powder size of the expanded perlite is characterized in that 1 ~ 300um,
In the expanded perlite mixing step (S100),
A basic anode active material mixing step of mixing 80 to 83 parts by weight of lead powder, 5 to 10 parts by weight of sulfuric acid, 10 to 15 parts by weight of water, and 1 to 3 parts by weight of negative electrode additives based on the total weight of the negative electrode active material; and
3 to 10 parts by weight of expanded perlite powder based on the total weight of the mixture was added to the mixture formulated in the basic anode active material mixing step, and stirred at a temperature of 55 to 75 degrees to obtain a negative electrode active material with a density of 75 to 80 g/in3. It is characterized in that it comprises a; negative electrode active material acquisition step,
It is characterized in that it can provide a lifespan improvement of 28.5% from 238 cycles without adding expanded perlite powder to 306 cycles when expanded perlite powder is added,
Charge acceptance is 16.43 to 19.93, characterized in that it can provide a current improvement of 21%, characterized in that the expanded perlite is applied to increase the surface area between the electrolyte and the active material negative plate manufacturing method of the lead-acid battery.
delete According to claim 1,
In the expanded perlite mixing step (S100),
Expanded perlite powder is added to increase the pore activation, reaction area with sulfuric acid, and internal electrical conductivity of the anode active material to increase the basic performance and charging efficiency of the lead-acid battery. By applying the expanded perlite, the surface area between the electrolyte and the active material A method for manufacturing a negative electrode plate of a lead-acid battery with increased
delete By the manufacturing method of claim 1,
A lead-acid battery including a negative plate of a lead-acid battery in which the surface area between the electrolyte and the active material is increased by applying expanded perlite.

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