JPH1021923A - Negative electrode plate for lead-acid battery, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a negative electrode plate for a lead-acid battery which can prolong the battery life in the use for a trickle charging at high tempera ture. SOLUTION: Active matter paste is made, which contains lead powder, lignin compound (sodium lignosulfonic acid), barium sulfate, fiber-shaped active matter reinforcing material, and a fluorinated interface activator expressed by CF3 (CF2 )n SO3 X (n is an integer of 3 to 17, X is H or Na) of 0.01-0.5wt.% to lead powder. A collector such as a lattice or the like is charged with active matter paste. This is aged and dried to transform 8 transformed electrode plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a negative electrode plate for a lead storage battery and a method for producing the same.

[0002]

2. Description of the Related Art In general, a negative electrode plate for a lead storage battery is manufactured as follows. First, a current collector such as a lattice is filled with an active material paste obtained by kneading lead powder, an additive, diluted sulfuric acid, and water. Next, this is aged and dried to form an unformed electrode plate to complete it. By adding a lignin compound to the active material paste and adding the lignin compound to the negative electrode active material,
It is known to increase the discharge capacity of lead storage batteries. The lignin compound increases the specific surface area of the negative electrode active material,
The charge / discharge reaction of the negative electrode active material is promoted, and the discharge capacity of the lead storage battery increases.

[0003]

However, since the lignin compound decomposes and disappears in an oxidizing atmosphere during charging, it has the effect of maintaining a high discharge capacity of the lead storage battery over a long period of use. descend. In particular, when the lead storage battery is trickle-charged in a high-temperature atmosphere, the effect of maintaining a high discharge capacity of the lead storage battery is significantly reduced.
Therefore, in the conventional negative electrode plate for a lead-acid battery, the battery life in the case of using a trickle cannot be extended.

An object of the present invention is to provide a negative electrode plate for a lead-acid battery, which can extend the life of the battery.

Another object of the present invention is to provide a negative electrode plate for a lead-acid battery which can extend the battery life in trickle charge use at high temperatures.

Another object of the present invention is to provide a method for producing a negative electrode plate for a lead-acid battery, which can smooth the surface of an active material paste layer when the active material paste is filled in a current collector.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a negative electrode plate for a lead-acid battery containing a lignin compound in the active material layer, the decomposition of the lignin compound being suppressed in the negative electrode active material layer,
And an amount of CF ₃ (CF ₂ ) _n S that does not decrease the discharge capacity
A fluorine-based surfactant represented by O ₃ X (n is an integer of 3 to 17, X is H or Na) is included. Here, the amount that does not decrease the discharge capacity is an amount that does not decrease the discharge capacity as compared with the case where the fluorine-based surfactant is not used.

When the fluorine-based surfactant of the above formula is included in the negative electrode active material as in the present invention, the decomposition of the lignin compound can be suppressed. The reason is that the lignin compound and the fluorine-based surfactant represented by the above formula attract each other, and dissolution of the lignin compound in the electrolytic solution is suppressed.
It is considered that decomposition is suppressed. for that reason,
ADVANTAGE OF THE INVENTION According to this invention, the capacity | capacitance of a battery can be maintained high over a long term use of a battery, and the battery life especially in trickle charge use under high temperature can be extended.

The lignin compounds include lignin sulfonic acid, lignin sulfonic acid sodium salt, thiolignin sulfonic acid, thiolignin sulfonic acid sodium salt, β
-Naphthalenesulfonic acid, β-naphthalenesulfonic acid sodium salt, or a modified type in which the number of sulfone groups, carboxyl groups, and hydroxyl groups thereof are changed can be used. In the use of a trickle, when lignin sulfonic acid is used, lignin sulfonic acid may be contained in an amount of 0.2 to 0.4% by weight based on lead powder, which is a main raw material of the active material layer, and thiolignin sulfonic acid may be used. When used, thioligninsulfonic acid is used in an amount of 0.1 to 0.2% by weight based on lead powder.
What is necessary is just to make it contain.

More specifically, for a negative electrode plate for a lead-acid battery containing a lignin compound, barium sulfate, and a fibrous active material reinforcing material in the active material layer, the negative electrode active material layer contains CF.
₃ (CF ₂ ) _n SO ₃ X (n is an integer of 3 to 17, X is H
Alternatively, a fluorine-based surfactant represented by Na) is contained in an amount of 0.01 to 0.5% by weight based on lead powder which is a main raw material of the active material layer. When such an amount is contained, the decomposition of the lignin compound is suppressed, and the discharge capacity does not significantly decrease. Also,
Barium sulfate can prevent lead sulfate particles from being coarsened and can suppress a decrease in discharge capacity. The active material reinforcing material can prevent the active material from falling off and extend the life of the electrode plate. Even if the content of the fluorinated surfactant changes the amounts of the lignin compound, barium sulfate and the fibrous active material reinforcing material, the effect is obtained in an amount of 0.01 to 0.5% by weight based on the lead powder. be able to. If the amount of the fluorine-based surfactant is less than 0.01% by weight based on the lead powder, the effect cannot be sufficiently obtained, and the battery life in trickle charge use at a high temperature cannot be extended. When the amount of the fluorine-based surfactant exceeds 0.5% by weight based on the lead powder, the capacity of the lead storage battery decreases. It is considered that this is because the movement of the electrolytic solution into the active material is inhibited by the fluorine-based surfactant, and the reaction area between the active material and the electrolytic solution is reduced. Note that the fluorine-based surfactant represented by the above formula has acid resistance and is hardly decomposed even under a strong acid. It is stable even in a high-temperature atmosphere.

When the current collector is filled with an active material paste containing the fluorine-based surfactant represented by the above formula, the surface of the active material paste layer can be smoothed. When a negative electrode plate for a lead-acid battery is manufactured using the agent, it is possible to prevent gas accumulation on the surface of the negative electrode plate, and it is possible to suppress variations in the charge amount of the battery.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A lead storage battery used in the test was manufactured as follows. First, lead powder, 0.2% by weight of sodium lignin sulfonate with respect to lead powder, 0.5% by weight of barium sulfate with respect to lead powder, and 0.1% by weight of polyester resin with respect to lead powder Active material reinforcing material consisting of short fibers and CF ₃ (CF ₂ ) in the amount shown in Table 1 (based on lead powder)
_{5 A} fluorine-based surfactant composed of SO ₃ Na (sodium perfluorohexylsulfonate) and 9.9% by weight of dilute sulfuric acid (specific gravity 1.260: 20 ° C.) based on lead powder are kneaded to obtain a density of 4 0.8 g / cc of each active material paste was prepared.

[0013]

[Table 1] Next, 15 g of each active material paste was filled in a 2 mm-thick current collector made of a lattice of a Pb-Ca-Sn-based alloy to prepare undried electrode plates. Next, each undried electrode plate was heated at 35 ° C., 9
Aged for 3 days in an atmosphere of 8% RH,
It is left to dry in an atmosphere of 0 ° C. and 20% RH for 1 day, and dried.
An unformed negative electrode plate was produced. Next, each unformed negative electrode plate and each known unformed positive electrode plate were subjected to a specific gravity of 1.050,
250% of the theoretical charge of the positive electrode plate
For 40 hours to form an unformed negative electrode plate, thereby completing each negative electrode plate.

Next, the positive electrode plate after formation is washed with running water for 30 minutes, dried at 50 ° C. for 16 hours, and the negative electrode plate after formation is washed with running water for 30 minutes, and then placed at 80 ° C. for 16 hours in a nitrogen gas atmosphere. And dried. Then, six cells were made by using a group of electrode plates made by combining three positive electrode plates, four negative electrode plates, and a retainer made of glass fiber in a battery case as one cell. Next, an electrolytic solution composed of dilute sulfuric acid having a specific gravity of 1.260 (20 ° C.) was injected into the battery case to complete sealed lead-acid batteries of 12 V-3 Ah used for the test.

Next, each of the above sealed lead-acid batteries was charged to an ambient temperature of 25.
At 150 ° C., discharge current 150 mA, end voltage 10.5 V
And the initial capacity of each sealed lead-acid battery (the relationship between the amount of the fluorine-based surfactant relative to the lead powder and the initial capacity) was examined. FIG. 1 shows the measurement results. From FIG. 1, it can be seen that the initial capacity of the sealed lead-acid battery increases with the addition of the fluorine-based surfactant (sodium perfluorohexylsulfonate). However, when the amount of the fluorine-based surfactant exceeds 0.5% by weight based on the lead powder, the initial capacity decreases. This is because if the amount of the fluorine-based surfactant increases more than necessary, the movement of the electrolyte into the active material is inhibited by the fluorine-based surfactant, and the reaction area between the active material and the electrolyte decreases. It is believed that there is.

Next, using the batteries of Examples 1, 3, 6 and Comparative Examples 1 to 3, at an ambient temperature of 45.degree.
Perform trickle charge at 3.5V and charge period (test period)
And the discharge capacity at 0.25 CA was examined.
FIG. 2 shows the measurement results. As shown in FIG. 2, a negative electrode plate to which no fluorine-based surfactant was added (Comparative Example 1) and a negative electrode plate in which the amount of the fluorine-based surfactant exceeded 0.5% by weight based on lead powder (Comparative Examples 2 and 3) were used. In the sealed lead-acid battery used,
It can be seen that the battery life in trickle charging can be extended.

In this embodiment, CF ₃ (CF ₂ ) ₅ S
Although an example using O ₃ Na (sodium perfluorohexylsulfonate) was shown, CF ₃ (CF ₂ ) _n SO _{3 was used.}
X (n is an integer of 3 to 17, X is H or Na) does not substantially change in action even when the value of n and the element of X are changed. In this example, sodium ligninsulfonate was used as the lignin compound. However, it was confirmed that the same effect as in this example can be obtained by using another lignin compound.

[0018]

According to the present invention, CF ₃ (CF ₂ ) _n S
Since the fluorinated surfactant represented by O ₃ X (n is an integer of 3 to 17, X is H or Na) is contained in the negative electrode active material, the decomposition of the lignin compound can be suppressed. Therefore, according to the present invention, the capacity of the battery can be maintained high over a long period of use of the battery, and the battery life can be prolonged, particularly in the case of trickle charging at high temperatures.

[Brief description of the drawings]

FIG. 1 is a diagram showing the initial capacity (the relationship between the amount of a fluorine-based surfactant with respect to lead powder and the initial capacity) of a sealed lead-acid battery used in a test.

FIG. 2 is a diagram showing a relationship between a charging period and a discharge capacity in trickle charging of the sealed lead-acid battery used for the test.

Claims (3)

[Claims] 1. A negative electrode plate for a lead storage battery containing a lignin compound in an active material layer, wherein the amount of CF ₃ (CF) in the negative electrode active material layer is such that the decomposition of the lignin compound is suppressed and the discharge capacity is not reduced. ₂ )
_n SO ₃ X (n is an integer of 3 to 17, X is H or Na)
A negative electrode plate for a lead storage battery, characterized by containing a fluorine-based surfactant represented by the formula: 2. A negative electrode plate for a lead-acid battery, comprising a lignin compound, barium sulfate and a fibrous active material reinforcing material in the active material layer, wherein the negative electrode active material layer comprises CF ₃ (CF ₂ ) _n SO ₃ X (N
Is an integer of 3 to 17, and X is H or Na). The fluorine-based surfactant is contained in an amount of 0.01 to 0.5% by weight based on lead powder, which is a main raw material of the active material layer. A negative electrode plate for a lead-acid battery, comprising: 3. A method for manufacturing a negative electrode plate for a lead storage battery by filling an active material paste containing lead powder and a lignin compound into a current collector, wherein the active material paste comprises CF ₃ (CF ₂ ) _n SO ₃ X
(N is an integer of 3 to 17, X is H or Na). A method for producing a negative electrode plate for a lead storage battery, characterized by containing a fluorine-based surfactant represented by the following formula: