JP3427402B2 - Method for manufacturing electrode plate for lead-acid battery - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a paste type electrode plate for a lead storage battery.

[0002]

2. Description of the Related Art A conventional lead-acid battery electrode plate is manufactured as follows. First, lead oxide, water, and dilute sulfuric acid are kneaded to form an active material paste, and the active material paste is filled in a current collector such as a grid body made of lead or a lead alloy to form an undried electrode plate. Next, this undried electrode plate is aged and dried to integrate the current collector and the active material, and then chemical conversion is performed to complete the process.

[0003]

However, since the active material paste prepared by kneading lead oxide, water and dilute sulfuric acid has a high viscosity, the active material and the current collector will be sufficient even if the undried electrode plate is aged and dried. There is a problem of not sticking to. Particularly in recent years, since an expanded current collector formed by expanding a rolled sheet having a flat surface is used as the current collector, it is even more difficult to adhere the active material paste to the surface of the current collector. . Therefore, when the battery using the conventional electrode plate is repeatedly charged and discharged, the active material is softened and easily falls off from the surface of the current collector, which causes a problem that the charge and discharge cycle life of the battery is shortened.

In order to prevent the active material on the surface of the current collector from falling off, a highly elastic mat-like separator mainly made of glass fiber is used as a separator interposed between the electrode plates. It has been proposed to improve the performance of the charge / discharge cycle by increasing the applied pressure to improve the adhesion between the active material and the current collector. However, in this case, it is extremely difficult to increase the pressing force at the time of assembly, and further improvement is required in the case of industrial mass production.

Further, in the conventional manufacturing method, when the undried electrode plate is aged, Pb + H ₂ O + 1/2 is formed on the surface of the current collector.
Since the reaction of O ₂ → Pb (OH) ₂ → PbO + H ₂ O occurs, a large amount of oxygen is required for aging the undried electrode plate, and there is a problem that aging takes a long time.

An object of the present invention is to provide a method for manufacturing a lead storage battery electrode plate which can prevent the active material from falling off from the surface of the current collector and can shorten the aging time.

[0007]

According to a first aspect of the present invention , a high level lead oxide is formed on the surface of a current collector made of lead or a lead alloy .
(PbOx: 1.13 ≤ X ≤ 2.0) and a slurry kneaded with water
Then, apply and contact the surface of the current collector with a tetragonal system.
After forming the lead oxide layer, lead oxide is mainly added to the current collector.
Of a lead-acid battery electrode plate filled with an active material paste as a component
In the manufacturing method, red lead is used as the high order lead oxide.
It is characterized by being

The invention of claim 2 is made of lead or lead alloy.
In that current collector, _lead, from _{PbO 1.37} and PbO ₂
At least one selected higher lead oxide (PbOx:
1.13 ≦ X ≦ 2.0) as the main component and kneaded with water
After making the wet electrode plate by filling the strike,
The plate is dried and aged to form tetragonal lead acid on the surface of the current collector.
In the method of manufacturing a lead storage battery electrode plate for forming a compound layer,
Anionic surfactant is added to the active material paste
It is characterized by

[0009]

The tetragonal lead oxide layer has a dense crystal structure of lead oxide (t-PbO, where t is tetoragonal t).
Is an oxidative corrosion layer formed from. Therefore, claim 1
When a tetragonal lead oxide layer is formed on the surface portion of the current collector as in the invention of No. 1, the adhesion between the current collector and the active material can be enhanced. When the electrode plate of the present invention is a positive electrode plate, when chemical conversion is performed,
By the solid phase reaction, the tetragonal lead oxide layer on the surface of the current collector becomes a lead oxide layer containing α-PbO ₂ . This lead oxide layer improves the adhesion between the active material and the current collector.

If the electrode plate of the present invention is a negative electrode plate, the tetragonal lead oxide layer on the surface of the current collector becomes a porous sponge-like metallic lead layer by chemical conversion. This sea-surface-like metallic lead layer also improves the adhesion between the active material and the current collector.

High-level lead oxide (PbO ) is formed on the surface of the current collector.
x: by contacting a 1.13 ≦ X ≦ 2.0), the electrochemical action of the current collector (local battery), it is possible to form the tetragonal lead oxide layer on the surface of the current collector. That is, the corrosion reaction of the current collector proceeds due to the diffusion of OH ⁻ . The movement and generation of ions are accelerated in the presence of water at higher temperatures, so contact with high-level lead oxides should be performed at high temperatures (below the softening point of the current collector) and in the presence of water. It is preferable. Therefore, the corrosion reaction (aging) proceeds in a short time even under the condition that oxygen diffusion is hindered as in the battery case. In addition, the range of X of PbOx is 1.13 ≦ X
By setting ≦ 2.0, the electromotive force of the reaction formula that corrodes (ages) the surface part of the current collector can be increased as shown in Table 1 and FIG. 1, so if X is in this range, corrosion is effectively promoted. can do.

[0012]

[Table 1] Further, the high lead oxide to make a slurry obtained by kneading with water, by applying this slurry on the surface of the current collector, can be easily brought into contact with high-order oxide on the surface of the current collector.

[0013] Especially as in the present invention, by using the red lead as high lead oxide, red lead, since relatively readily available, can be easily carried out the production method of the present invention.

According to a second aspect of the present invention, the current collector is coated with an active material paste containing high-grade lead oxide (PbOx: 1.13≤X≤2.0) as a main component and kneaded with water to form a undried electrode plate. create
As a result, due to the electrochemical action of the current collector and lead oxide (local battery), a tetragonal lead oxide layer is formed on the surface of the current collector when the undried electrode plate is aged and dried. It Therefore, an electrode plate having high adhesion between the current collector and the active material can be produced in a short time by a simple operation of simply applying the active material paste.

As described above, in the conventional case, the surface portion of the current collector is Pb + H ₂ O + 1 / 2O when the undried electrode plate is aged.
It is oxidized by the reaction formula of ₂ → Pb (OH) ₂ → PbO + H ₂ O, and its electromotive force is about 0.8 V in consideration of the oxygen concentration which can be dissolved in H ₂ O in the paste. And <br/> pairs thereto, minium as high lead _oxide, to use at least one selected from _{PbO 1.37} and PbO ₂
As a result , each high-ranking lead oxide reacts with lead on the surface portion of the current collector, and the electromotive force for generating PbO can be made higher than 0.8V. Therefore, aging of the current collector can be greatly promoted as compared with the conventional case. For example, when lead oxide (Pb ₃ O ₄ ) is used as the high-order lead oxide, the surface portion of the current collector is Pb ₃ O ₄ + Pb → 4PbO (Pb ₃ O).
₄ + 4H ₂ O + 2e- → 3Pb (OH) ₂ + 2O
H−, Pb + 2OH− → PbO + H ₂ O), and the electromotive force is 0.835V. When PbO ₂ is used as the high-order lead oxide, the surface portion of the current collector is PbO ₂ + Pb → 2PbO (PbO ₂ + 2e−
→ PbO + O ² −, Pb + O ² − → PbO + 2e
Aged with the reaction formula of −), and its electromotive force is 0.834V
Becomes When PbO _1.37 is used as the high-ranking lead oxide, PbO _1.37 becomes α-PbO by the reaction with dilute sulfuric acid.
₂ , and a denser corrosion layer than the case where lead oxide (Pb ₃ O ₄ ) is used is formed at the interface between the current collector and the active material.

[0016] Especially as in the present invention, active in material paste by adding an anionic surfactant, because the particles of the paste OH- is exposed on the surface repel each other by anionic (negatively charged particles) particles Comrades will roll each other. Therefore, the wettability of the active material paste to the current collector is improved, and the active material paste is easily leveled (flattened). Therefore, according to the present invention, the adhesion of the active material to the current collector can be made substantially uniform over the entire electrode plate.

[0017]

EXAMPLES Examples will be shown below to more specifically describe the present invention, but the present invention is not limited to these examples.

Example 1 Various positive electrode plates (size 86 × 56 × 2.4 mm) a to i including the examples of the present invention were prepared by using an expanded grid made of a lead-tin-calcium alloy as a current collector. The characteristics of each electrode plate were examined. If the positive electrode plate a is made of lead monoxide for the current collector, lead oxide 8
It is a conventional electrode plate made by filling a conventional active material paste prepared from 0% by weight, 30% by weight sulfuric acid 13% by weight, and water 7% by weight. The positive electrode plate b has a collector of 80% by weight of lead tin and 30
% Of sulfuric acid and 7% by weight of water are kneaded, and the conventional electrode plate is made by filling the active material paste.

The positive electrode plate c has a collector of 70% by weight of lead tin and 3 parts of water.
After applying a slurry prepared by kneading 0% by weight and standing for 16 hours to form a tetragonal lead oxide layer on the surface of the current collector, the conventional active material paste used in the positive electrode plate a was applied. It is the electrode plate of the Example of this invention produced by filling. The positive electrode plate d has a current collector of 50 wt% α-PbO ₂ , 15 wt% of red lead and 35 wt.
After applying a slurry prepared by kneading with the composition of the present invention and leaving it for 16 hours, the active material paste prepared by kneading 89% by weight of red lead and 11% by weight of water was filled. It is a polar plate. The positive electrode plate e was applied with the slurry used for forming the positive electrode plate c on the current collector and then heat-treated at 180 ° C. for 5 minutes, and then 80% by weight of lead tin, 13% by weight of sulfuric acid and 7% by weight of water.
It is an electrode plate of an embodiment of the present invention, which is prepared by filling an active material paste prepared by kneading and.

The positive electrode plate f has a collector of 89% by weight of lead tin and 1 part of water.
1 is an electrode plate of an example of the present invention, which is prepared by filling an active material paste prepared by kneading 1% by weight. The positive electrode plate g is an electrode plate of an embodiment of the present invention, which is made by filling a current collector with an active material paste made of 89% by weight of PbO ₂ and 11% by weight of water. The positive electrode plate h is an electrode plate of an embodiment of the present invention made by filling an active material paste prepared by kneading 89% by weight of PbO _1.37 and 11% by weight of water in a current collector. The positive electrode plate i has a collector of PbO _1.37 89% by weight and water 11% by weight.
It is an electrode plate of an example of the present invention made by filling an active material paste prepared by kneading and 0.05% by weight of an anionic surfactant composed of benzene sulfonate.

The amount of the active material paste filled in each of the positive electrode plates a to i was 30 g, and each of the positive electrode plates was left to stand at 40 ° C. for 16 hours to be aged and then formed under the same conditions. went. Then, each positive electrode plate a to i is laminated with the same type of negative electrode plate (dimensions 86 × 56 × 1.6 mm) via the electrolytic solution holder made of a non-woven fabric of glass fiber to make sealed lead acid batteries A to I. A battery capacity test and a cycle test were performed. The test condition of the capacity test is 1A discharge (cutoff voltage 1.75
V), and the test condition of the cycle test is 1A discharge (end voltage 1.75V) ← → 2.45V constant voltage charge 3 hours (limit current 1.
4 A).

The result of the capacity test is shown in FIG. 2, and the result of the cycle test is shown in FIG. As shown in FIG. 2, in the batteries C to I using the electrode plate of this example, the initial capacity increased by 5 to 15%.
Further, as shown in FIG. 3, the cycle characteristics of the batteries C to I using the electrode plate of this embodiment tend to be longer than those of the batteries A and B using the conventional electrode plate.

Example 2 Next, an example of manufacturing a negative electrode plate according to the present invention will be described. The negative electrode plate (size 86 × 56 × 1.6 mm) was prepared by using an expanded grid made of a lead-tin-calcium alloy as a current collector. The negative electrode plate j was 85% by weight of lead oxide and 9% of dilute sulfuric acid.
It is a conventional electrode plate prepared by using a conventional active material paste prepared by kneading 1% by weight and 6% by weight of water. The negative electrode plate k was prepared by kneading 40% by weight of β-PbO ₂ and 60% by weight of water. The slurry was applied to the current collector and left for 16 hours, and then the conventional active material paste used for the negative electrode plate j was used. 2 is an electrode plate of an example of the present invention obtained by filling Then, each of the negative electrode plates j and k is laminated with the positive electrode plate d of this embodiment used in the above-mentioned test through the electrolytic solution holder made of a non-woven fabric of glass fiber to form sealed lead-acid batteries J and K, A cycle test and a trickle test of each battery were performed. The test conditions of the cycle test were 1 A discharge (final voltage 1.75 V) ← → 2.45 V constant voltage charging for 3 hours (limit current 1.4 A), and the trickle test was 2.27 V constant voltage charging method.

FIG. 4 shows the result of the cycle test. When the electrode plate of the present invention is applied to the positive electrode plate and the negative electrode plate as shown in the figure, the cycle life of the battery can be further improved as compared with the case where the electrode plate of the present invention is used for the positive electrode plate.

FIG. 5 shows the results of comparison of the trickle currents of the conventional negative electrode plate and the negative electrode plate of this embodiment. From the figure, it can be seen that the trickle current of the battery can be reduced by using the electrode plate of this embodiment. Next, the relationship between the temperature applied after applying the slurry prepared by kneading lead tin and water to the current collector and the change with time in the thickness of the lead monoxide layer formed on the surface of the current collector during aging Examined. The electrode plate 1 is an electrode plate obtained by applying a slurry prepared by kneading 50% by weight of lead tin and 50% by weight of water to a current collector and then performing heat treatment at 180 ° C. for 3 minutes. The electrode plate m is an electrode plate that is not heat-treated, and was made in the same manner as the electrode plate 1 except for the heat treatment. And, 80% by weight and 30% by weight of lead oxide are applied to each electrode plate 1 and m.
A conventional active material paste prepared from 13% by weight of sulfuric acid and 7% by weight of water was filled, and the change in thickness of the lead monoxide layer during aging was measured. FIG. 6 shows the measurement result. In this figure, the conventional positive electrode plate a used in the above-mentioned test is shown.
The measurement results of are also shown. From this figure, it can be seen that the thickness of the lead monoxide layer can be increased in a short time by applying heat treatment after applying the slurry to the current collector.

Next, the above-mentioned conventional positive electrode plate a prepared by using the conventional active material paste, and a slurry prepared by kneading lead tin and water on the current collector are applied and heat-treated, and then lead tin The positive electrode plate e of the above-described embodiment made by filling the active material paste containing
Batteries A, E, and N were made from the positive electrode plates n prepared by replacing the conventional active material paste prepared from 13% by weight of sulfuric acid (0% by weight and 30% by weight) and 7% by weight of water. Was investigated for capacity recovery. The test conditions were that each battery was left for 24 hours at a constant resistance of 0.5 ohm, then left in a circuit condition for 3 months in an atmosphere of 25 ± 2 ° C., and then charged at 2.45 V (limit current 1.2 A) for 4 hours. Then, it was discharged at 0.25 CA and measured. FIG. 7 shows the measurement result. From this figure, it can be seen that a battery having excellent recovery performance can be obtained by using the electrode plates e and n of the embodiment.

[0027]

According to the invention of claim 1, since a tetragonal lead oxide layer having a dense crystal structure made of lead oxide (t-PbO) is formed on the surface of the current collector, Adhesion between the current collector and the active material can be improved. Therefore, according to the present invention, it is possible to obtain an electrode plate that can improve the cycle characteristics and trickle characteristics of the battery.

[0028] In addition, oxide of high-level on the surface of the current collector (Pb
Ox: 1.13 ≦ X ≦ 2.0), so that a tetragonal lead oxide layer can be formed on the surface portion of the current collector by an electrochemical action (local battery) with the current collector.

Further , since a high-level lead oxide slurry is prepared and applied to the surface of the current collector, the high-level oxide can be easily brought into contact with the surface of the current collector.

Particularly, in the present invention, since lead oxide is used as the high-ranking lead oxide, the production method of the present invention can be easily carried out.

According to the second aspect of the present invention, the current collector is coated with an active material paste containing high-grade lead oxide (PbOx: 1.13≤X≤2.0) as a main component and kneaded with water to form a undried electrode plate. Because of the electrochemical action of the current collector and lead oxide (local battery), a tetragonal lead oxide layer is formed on the surface of the current collector when the undried electrode plate is aged and dried. . Therefore, an electrode plate having high adhesion between the current collector and the active material can be manufactured in a short time by simply applying the active material paste.

Further , as high-ranking lead oxide, red lead and PbO
_Since at least one selected from _1.37 and PbO ₂ is used, each high-order lead oxide can react with lead on the surface portion of the current collector to increase the electromotive force that produces PbO. Therefore, aging of the current collector can be greatly promoted as compared with the conventional case.

Particularly in the present invention, since the anionic surfactant is added to the active material paste, the adhesion of the active material to the current collector can be made substantially uniform over the entire electrode plate.

[Brief description of drawings]

FIG. 1 is a diagram showing a limited range of X in a high-order oxide PbOx used for an electrode plate of the present invention.

FIG. 2 is a comparison diagram of initial capacities of a battery using a positive electrode plate of an example of the present invention and a battery using a conventional positive electrode plate.

FIG. 3 is a comparison diagram of discharge cycle tests of a battery using a positive electrode plate of an example of the present invention and a battery using a conventional positive electrode plate.

FIG. 4 is a cycle test comparison diagram of a battery using the negative electrode plate of the example of the present invention and a battery using the conventional negative electrode plate.

FIG. 5 is a trickle current comparison diagram of a battery using the negative electrode plate of the example of the present invention and a battery using the conventional negative electrode plate.

FIG. 6 is a diagram showing a relationship between a temperature at which a current collector is pre-coated with a red lead slurry layer and heating, and a change with time in the thickness of a lead monoxide layer formed on the surface of the current collector during aging. is there.

FIG. 7 is a diagram showing capacity recoverability of a battery using a positive electrode plate of an example of the present invention and a battery using a conventional positive electrode plate.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiko Inui 1-1-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Within Kobe Electric Co., Ltd. (72) Inventor Miura Asahiko 2-chome, Nishi-Shinjuku, Shinjuku-ku, Tokyo No. 1 in Shin-Kobe Electric Co., Ltd. (72) Inventor Shinji Saito No. 1-1-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Inside Shin-Kobe Electric Co., Ltd. (56) Reference JP-A-53-3631 (JP, A) JP-A-60-86757 (JP, A) JP-A-63-66852 (JP, A) JP-A-55-163769 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 4/64-4/84 H01M 4/14-4/23

Claims (2)

(57) [Claims] 1. A surface of a current collector made of lead or a lead alloy.
High lead oxide (PbOx: 1.13 ≦ X ≦ 2.0) in water
Is applied as a slurry kneaded with and brought into contact with the current collector.
After forming a tetragonal lead oxide layer on the surface of the
Fill an electric conductor with an active material paste containing lead oxide as the main component
A method of manufacturing a lead-acid battery electrode plate according to claim 1, wherein lead oxide is used as the high-order lead oxide.
A method for manufacturing a lead-acid battery electrode plate . 2. A current collector comprising lead or lead alloy, lead
Tan, PbO _1.37 and PbO ₂ selected less
Both are high-grade lead oxides (PbOx: 1.13 ≦ X ≦ 2.0
) As the main component and filled with an active material paste kneaded with water.
After making the undried electrode plate, dry and ripen the undried electrode plate.
Forming a tetragonal lead oxide layer on the surface of the current collector
In the method for producing a lead-acid battery electrode plate, a method for producing a lead-acid battery electrode plate, characterized in that an anionic surfactant is added to the active material paste .