JP3287127B2 - Manufacturing method of lead storage 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 for producing a lead-acid battery having improved high-rate discharge characteristics immediately after chemical formation, particularly, improved characteristic deterioration at extremely low temperatures.

[0002]

2. Description of the Related Art A lead-acid battery using a lead-tin-calcium alloy for a positive electrode and / or a negative electrode grid has characteristics such as low self-discharge and excellent storage characteristics, and is easy to maintain. Therefore, it is used for various purposes. In such a battery, a method of manufacturing an electrode plate using an expanded lattice obtained by rolling a lead-tin-calcium alloy into a sheet and then expanding the sheet is widely used.

On the other hand, in the process of manufacturing an electrode plate using the expanded grid, when the grid is filled with an active material paste, the grid is made of a very thin cellulose-based material called paste paper (0.03 to 0.05 mm). A degree) thickness of paper is placed on both sides of the electrode plate. This is because, after filling the paste, a plurality of electrode plates cut to a predetermined size are stacked and aged and dried, so that at that time, the electrode plates are prevented from adhering to each other, and in order to hold the active material. It is.

[0004]

Conventionally, paste paper has been
Those wet strength exceeds 0.7 kg / mm ² are commonly used, structure using an electrode plate which it was placed on both sides
Immediately after injection chemical conversion within the battery container with dilute sulfuric acid for forming the battery,
The paste paper simply adheres to the electrode plate surface in a swollen state and remains. This is because by adding a polymer resin called a wet strength agent to the raw pulp, the strength becomes stronger than the original strength due to the entanglement of the fibers.
After that, when the battery is left or charged / discharged, the wet strength agent as a polymer resin and the cellulose of the fiber are gradually oxidized and decomposed in sulfuric acid, and finally dissolved in the electrolytic solution. However, it takes about 6 months to 1 year to completely dissolve. For this reason, in a state immediately after the formation, the supply of sulfuric acid to the active material is hindered by the paste paper remaining on the surface of the electrode plate, and the high-rate discharge characteristics are reduced. In particular, under the condition of extremely low temperature (−30 ° C.), since the viscosity of sulfuric acid is high, the adverse effect of the paste paper inhibiting the supply of sulfuric acid appears more remarkably.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a method for producing a lead-acid battery which is excellent in high-rate discharge characteristics and whose characteristics are not significantly deteriorated even at an extremely low temperature.

[0006]

In order to achieve the above object, the present invention provides a method for producing a lead-acid battery using an expanded grid made of a lead-tin-calcium alloy for a positive electrode and / or a negative electrode. The wet strength of the paste paper used in the step of filling the expanded lattice with the paste is 0.5 kg / mm ² or less.

When paste paper having a fiber length of the raw pulp of 1 to 3 mm is used, or when a polyamidoamine / epichlorohydrin resin is used as a wet strength agent, the amount of the pulp added is 0.2% by weight relative to the pulp. The use of the following paste paper is particularly effective.

[0008]

According to the present invention, the degree of entanglement between fibers is suppressed by the above-described structure, and the fibers are easily dispersed in sulfuric acid as an electrolyte. This bond is easily broken by oxidative degradation of the resin. For this reason, although the paste paper remains on the electrode plate immediately after the formation in the battery case, the fibers are loosened and dispersed, which substantially inhibits the supply of sulfuric acid to the active material of the electrode plate. Nothing. As a result, it is possible to improve the high-rate discharge characteristics, and in particular, suppress the characteristic deterioration at cryogenic temperatures.

[0009]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a grid 1 which is obtained by expanding a lead alloy sheet made of a lead-tin-calcium alloy and expanding it in a mesh form. FIG. 4 is a partial cross-sectional view of an electrode plate disposed on both sides, and shows a positive electrode using two types of paste papers A and B;
Two types of each negative electrode were prepared. Here, the paste paper A is
The wet strength is about 0.3 kg / mm ² , and a polyamidoamine / epichlorohydrin resin is added as a wet strength agent in an amount of 0.1% by weight relative to the raw material pulp, and the average fiber length is about 2 m.
The paper is made using pulp of m as a raw material, and has a basis weight of about 15 g / m ² and a thickness of about 0.03 mm. on the other hand,
Paste paper B has a wet strength of about 1.0 kg / mm ² , is made by adding 0.4% by weight of the same wet strength agent as A, and using pulp having an average fiber length of about 3 mm as a raw material. The basis weight and thickness are almost the same as A.

Next, an electrode group is formed by using an unformed positive electrode plate and a negative electrode plate, which are housed in a battery case, and a lid is attached thereto. Two types of lead-acid batteries A and B were created for automotive vehicles with nominal specifications of 12V48Ah. Here, the battery A is composed of an unformed positive electrode plate and a negative electrode plate to which the paste paper A is applied, and the battery B is composed of a positive electrode plate and a negative electrode plate made of the paste paper B. Therefore, battery A is one embodiment of the present invention, and battery B
Is a conventional example. The results of measuring the high-rate discharge characteristics at −30 ° C. using these batteries are shown in (Table 1).

[0012]

[Table 1]

From the results shown in Table 1, it is clear that the battery A has twice or more the characteristics of the battery B in the high-rate discharge characteristics at a low temperature.

On the other hand, when the state of the electrode plate immediately after the formation of the batteries A and B was examined, the paste paper almost retained its original shape on the surface of the electrode plate of the battery B, and was merely swollen with sulfuric acid. However, in the battery A, a part of the paste paper was loosened and dispersed and dropped from the electrode plate, and the remaining part was also loosened and dispersed in the remaining part. Condition. This is the battery A of the present embodiment.
By setting the wet strength of the paste paper to 0.3 kg / mm ² as described above, the dispersion of the fibers of the paste paper or the dissolution in sulfuric acid, which is an electrolytic solution, has already progressed immediately after chemical formation, and the electrode Not hinder the supply of sulfuric acid to
High rate discharge characteristics at extremely low temperatures are improved.

Next, the average fiber length is 1 mm, 2 mm, 3 mm
And 4 types of paste paper made of 4 mm raw pulp were prepared, and batteries were prepared in the same manner as the batteries A and B.
High rate discharge characteristics at 30 ° C. were measured. The result is shown in FIG.

When the fiber length is 4 mm, the wet strength is 0.5
It is beyond the kg / mm ^2, also, as is clear from FIG. 2, the fiber length is seen that it is desirable to use a from to exceed 3mm when property deterioration increases following 3mm. However, if the fiber length is less than 1 mm, papermaking by a paper machine becomes difficult. Therefore, the fiber length is desirably 1 to 3 mm.

Next, a polyamidoamine / epichlorohydrin resin was used as a wet strength agent, and the added amount was 0.1% by weight, 0.2% by weight, 0.3% by weight, 0.4% by weight relative to the raw material pulp. A total of five kinds of four types of paste paper and a paste paper to which no wet strength agent was added were prepared, and a battery was prepared using these paste papers in the same manner as the batteries A and B. FIG. 3 shows the results of measuring the rate discharge characteristics.

From these results, it can be seen that it is desirable from the viewpoint of discharge characteristics that the addition amount of the wet strength agent be 0.2% by weight or less. The wet strength agent for the paste paper may be a melamine-formaldehyde resin, a urea-formaldehyde resin or the like in addition to the polyamidoamine / epichlorohydrin resin. Any amount can be used as long as the amount is not more than mm ² .

In the above embodiment, both the positive electrode plate and the negative electrode plate use an electrode plate on which paste paper is disposed. However, when the electrode plate is used for either the positive or negative electrode plate, for example, Even in the case of a hybrid type lead-acid storage battery composed of an electrode plate using an expanded lattice body in which paste paper is disposed on a negative electrode plate, The high rate discharge characteristics at such a very low temperature can be improved.

[0020]

As is apparent from the above description, according to the present invention, in the manufacturing process of a lead-acid battery comprising an electrode plate using an expanded grid, the wet strength is 0.5 kg / mm.
By using a paste paper that is ² or less, even immediately after the formation in the battery case, the dispersal of the paste paper remaining on the surface of the electrode plate is improved, especially at an extremely low temperature such as -30 ° C. In addition, a lead-acid battery having excellent high-rate discharge characteristics can be realized.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a state in which paste paper is arranged on the surface of an electrode plate using an expanded lattice according to an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between the average fiber length of paste paper and the high-rate discharge characteristics at −30 ° C.

FIG. 3 shows the amount of a wet strength agent added to paste paper and -30.
Diagram showing relationship with high-rate discharge characteristics at ℃

[Explanation of symbols]

 1 Expanded lattice 2 Paste 3 Paste paper

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-121252 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 4/14-4/20 D04H 1 / 00-18/00

Claims (2)

(57) [Claims] 1. A method for producing a lead-acid battery using an expanded grid made of a lead-tin-calcium alloy as a positive electrode and / or a negative electrode, wherein a paste paper used in a step of filling the expanded grid with a paste is used. Ri der wet strength 0.5kg / mm ² or less, the original of the paste paper
Preparation of lead battery an average fiber length of the fee pulp characterized 1mm~3mm der Rukoto 2. A paste paper to which a polyamidoamine / epichlorohydrin resin as a wet strength agent is added in an amount of 0.2% by weight or less based on the raw pulp.
Process for the preparation of 1 Symbol placement of lead-acid batteries.