JPH0362452A - Preparation of lead-acid secondary battery - Google Patents

Abstract

PURPOSE:To suppress an anode plate from deteriorating at high temperature use without deteriorating workability of paste packing process by depleting a liquid after injection of an aqueous lignin solution in a prescribed concentration to a lead-acid battery which is prepared by assembling electrode plates not yet chemically converted and injecting a diluted sulfuric acid. CONSTITUTION:An aqueous lignin solution is once injected to a lead-acid battery which is prepared by assembling electrode plates not yet chemically converted and then depleted. After then, a diluted sulfuric acid in a prescribed concentration is injected for chemical conversion of the electrodes. When the lignin is injected to the battery as an aqueous solution, it adheres to the finely porous and not yet chemically converted electrode plates. The specific surface area of an anode active mass depends on the amount of the lignin in the active mass and controls the function of the anode plate. As a result, by this preparation, the anode plate is prevented from deteriorating its functions at high temperature use without lowering workability of paste packing process.

Description

[Detailed description of the invention] Industrial applications The present invention relates to lead acid batteries.

Conventional technology In conventional lead-acid batteries, the cathode plate is made of active material at the paste stage (obtained by kneading lead powder with water and dilute sulfuric acid), which becomes the active material after drying, drying, and chemical formation. Lignin has been added as an antishrink agent for materials.

Problems to be Solved by the Invention However, in recent years, the environment in which lead-acid batteries are used has become hotter, and deterioration in the performance of the cathode plate due to decomposition and reduction of lignin has become apparent.

As a solution to this problem, in order to ensure the absolute amount of lignin,
When the amount added in the conventional method was increased, the following problems occurred. That is, as shown in the drawing, from 0.2% to 0
．． At 4%, the penetration (paste properties) varies greatly due to slight variations in the water content, resulting in a drawback that workability when filling the lead alloy grid with paste is significantly reduced. In the drawings, A indicates a region where the paste is smoothly filled into the grid.

Means for Solving the Problems An object of the present invention is to add a large amount of lignin to a cathode plate without reducing workability during paste filling.

In order to achieve the above object, a lignin aqueous solution of a predetermined concentration is injected into a lead-acid battery assembled with unformed electrode plates.

It is believed that functional lignin, when injected into the battery as an aqueous solution, adsorbs to the microporous unformed plates.

Example 0.2% of the total weight of the lead powder used in the battery was added to an unformed electrode plate battery consisting of a cathode plate prepared using a paste kneaded with 0.2% of lignin added to the weight of lead powder. % of lignin was once injected and then deliquified, and then diluted sulfuric acid was injected to form a container.

The battery according to the present invention (55D23 type) was subjected to a life test at 80°C (JIS pattern, lOO
cycle).

Table 1 shows the specific surface area of the cathode active material before and after the life test.

(n=3) The specific surface area depends on the amount of lignin in the active material and is considered to control the performance of the electrode plate. However, as can be seen from Table 1, in the present invention, even after 100 cycles of the JIS life test, the lignin It is thought that this is secured more than in the previous initial period.

In addition, the results of a life test according to the SAE standard at high temperature (80°C) are shown.

Table 2 (n=3) It seems that the number of life cycles increased due to the increase in the amount of lignin in the life test according to the high temperature SAE standard.

Effects of the Invention As described above, according to the present invention, it is possible to suppress the performance deterioration of the cathode plate during high-temperature use without impairing workability during paste filling.

Further, according to the present invention, since the concentration of sulfuric acid in the vicinity of the electrode plate is low in the early stage of battery cell formation, formation can proceed efficiently.

[Brief explanation of drawings]

The drawing is a relationship curve diagram between paste moisture content, paste penetration, and lignin addition amount.

Claims (1)

[Claims] Manufacture of a lead-acid battery, characterized in that a lignin aqueous solution of a predetermined concentration is once injected into a lead-acid battery assembled with unformed electrode plates, the liquid is removed, and then dilute sulfuric acid of a predetermined concentration is injected to form a battery. Method.