JPS63195959A - Manufacture of lead acid battery - Google Patents

Abstract

PURPOSE:To increase the discharge capacity by making adhere slurry prepared by mixing lead oxide or lead powder with ethyl alcohol or water in which KOH or NaOH is dissolved and glycerin or ethylene glycol on an antimony-free alloy grid, and drying to form a film on the grid. CONSTITUTION:Slurry prepared by mixing lead oxide or lead powder with ethyl alcohol or water in which KOH or NaOH is dissolved and glycerin or ethylene glycol is made to adhere on an antimony-free alloy grid, then dried to form a film. The active material paste is filled in the grid to form a positive plate. Low specific gravity sulfuric acid is poured in a lead-acid battery using the positive plate and the in-container formation is conducted, then the sulfuric acid is replaced with high specific gravity sulfuric acid. Thereby, the cycle performance of the lead-acid battery in which an antimony free alloy grid is used can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a lead-acid battery using a lead alloy grid that does not contain antimony (hereinafter referred to as antimony-free).

Traditional technology and its problems currently lead? The lead alloy of the grid used in B batteries is lead-
Lead-acid batteries can be broadly divided into antimony-based and antimony-free types, and the characteristics of lead-acid batteries vary significantly depending on these lattice alloys. That is, when a lead-antimony alloy lattice is used, it exhibits excellent characteristics in deep charge/discharge cycles, but has the disadvantage of large self-discharge.

On the other hand, lead-acid batteries that use antimony-free alloy lattices have advantages such as less self-discharge, less loss of electrolyte during use, and no need for water replenishment, but they do not require deep charging and discharging. If this is repeated, the battery capacity will decrease prematurely, resulting in poor cycle performance, which is a fatal drawback. This is caused by the positive electrode plate, and when a battery whose capacity has decreased prematurely is disassembled and the positive electrode plate is observed, there is no apparent abnormality, but upon closer inspection, a nonconductor is found at the interface between the lattice and the active material. It can be seen that layers are formed. Since this nonconductor layer is generated at the beginning of discharge, the polarization of the positive electrode plate becomes large and sufficient discharge capacity cannot be obtained.

Means for Solving the Problems The present invention applies a slurry prepared from lead oxide or lead powder, ethyl alcohol or water in which KOH or OOH is dissolved, and glycerin or ethylene glycol to the surface of an antimony-free alloy lattice. , which is characterized by forming a coating vA on the surface of the grating through drying treatment, thereby making it possible to eliminate the above-mentioned drawbacks.

Example An embodiment of the present invention will be described below.

In this example, R+-C is used as the antimony-free alloy lattice.
An extended band lattice made of an a-Sn alloy was used. Since this lattice is more prone to early capacity reduction than a cast lattice made of Pb--Ca--Sn alloy, it is possible to quickly determine whether or not it is effective. The surface pattern of the grid was formed as follows. First, 0)-1 seaweed per 100cc of ethyl alcohol.
Alternatively, 59% of KOI-1 was dissolved, a mixed solution of 1 part of this solution and 1 part of glycerin was prepared, and then 500 cc of the above mixed solution was added to 1 g of lead oxide with stirring to prepare a slurry. The slurry thus prepared is somewhat viscous and has the property of hardening in a short time when left in the air. Therefore, the above-mentioned expanded grid was immersed in the slurry for a short time, taken out, and then left in the air for several hours.

As a result, the surface of the grating has a thickness of 0.2~0.5+nm.
The battery was covered with a hard film, and the film did not peel off even after filling with storage battery paste. The filled electrode plate was aged by a conventional method, and then combined with a negative electrode plate of a Pb-Ca-Sn alloy lattice to produce an automobile battery with a nominal capacity of ff128Δh (5hR), and the electrolyte specific gravity was 1.28. (20° C.), and then the following charge/discharge test was conducted.

Discharge: Discharge to 1.75 V/cell at 5 hR current (5,6△) Charge: Charge 130% of the discharge amount at 3.6 A Temperature: 25°C The contents of the batteries used in the test are shown in Table 1, and The results of the test are shown in Figure 1.

According to the present invention, the test batteries A-D are Na0l-i or K
This battery uses a positive electrode grid in which the grid is treated with a lead oxide slurry prepared by vA with a mixed solution of OH in ethyl alcohol and glycerin, and a film is formed on the surface of the grid. Also,
E and F are control products in which a film was formed on the surface of the lattice using a slurry containing neither ff1ol-1 nor KOH, and G and H are conventional products. Here, each of the batteries A, C, E, and G was injected with am with a specific gravity of 1.05, and after 20 hours of battery cell formation with an amount of electricity of 200% of the theoretical capacity of the positive electrode,
The electrolyte was drained and mixed with high-density sulfuric acid to adjust the specific gravity of the electrolyte to 1.28. On the other hand, for B, D, F, and H, sulfuric acid having a specific gravity of 1.22 was injected, and battery cell formation was performed for 20 hours with an electricity amount of 300% of the theoretical capacity of the positive electrode. In this case, the specific gravity of the electrolyte becomes 1.28 when the chemical formation is completed, so there is no need for hind limbs.

The following can be seen from the test results shown in Table 1 and Figure 1. First, in a 10-cycle charge/discharge test, samples A and C according to the present invention showed the least decrease in capacity. In this case, the grating surface was treated with a slurry containing nOH or KOH, and low-density sulfuric acid was poured into the cell to form a cell. Compared to conventional product G, which was formed into a container under these conditions, the capacity drop is clearly smaller.

That is, the 5hR capacity of the products Δ and C of the present invention at the 10th cycle was 4 h prior, while that of the conventional product G was 211.

On the other hand, control product E, in which the lattice was treated with a slurry to which neither Na01-1 nor KOH was added, showed the same capacity change as conventional product G. Therefore, in order to prevent capacity reduction during charge/discharge cycles, it is necessary to take precautions when preparing slurry.
It can be seen that it is important to add an alkali such as 1 or KO).

However, test batteries A and C, which showed such excellent cycle performance, showed poor cycle performance like batteries B and D when the test batteries A and C were injected with sulfuric acid with a high specific gravity (1,22) in a Ti battery. become. The cycle performance of B and D was slightly better than that of control product F and conventional product L, but it was far inferior to A and C. Therefore, in order to improve the cycle performance of a lead-acid battery using a lead-calcium alloy lattice according to the present invention, the lattice can be made of Nao)-1 or KOH as described above.
It is necessary to form a film on the surface by treating it with a slurry containing an alkali such as the above slurry, and to form a battery case by injecting low specific gravity sulfuric acid.

In this example, the lead oxide slurry was mixed with nOH or K.
81 with a mixed solution of OH ethyl alcohol and glycerin
However, instead of lead oxide, ordinary lead powder (Pb070 ~
The same ght! was gotten.

The thickness and strength of the surface coating will vary depending on the blending ratio of these, but 200 to 400 cc of ethyl alcohol and 100 to 400 cc of glycerin per 1 kg of lead oxide.
, alkaline concentration of 1 to 10 g/100 cc of ethyl alcohol is sufficient.

Effects of the Invention As detailed above, the present invention makes it possible to improve the cycle performance of a lead-acid battery using an antimony-free alloy lattice, and has great industrial value.

[Brief explanation of the drawing]

FIG. 1 compares the charge/discharge cycle characteristics of a test battery based on the present invention and a conventional product.

Claims (1)

[Claims] 1. A slurry prepared by kneading lead oxide or lead powder with an ethyl alcohol solution of NaOH or KOH or a mixed solution of either of them and a mixed solution of glycerin or ethylene glycol is attached to the surface of a lead alloy grid that does not contain antimony. A lead-acid battery whose positive electrode is an electrode plate filled with storage battery paste in a lattice body subjected to drying treatment is formed into a battery by injecting sulfuric acid of low specific gravity, and then the liquid is replaced with sulfuric acid of high specific gravity. Manufacturing method for lead-acid batteries.