JPS6041758A - Manufacture of plate for alkaline storage battery - Google Patents

Abstract

PURPOSE:To increase impregnation efficiency by adding nitric acid to molten salt or concentrated solution of nickel nitrate or cadmium nitrate and immersing a porous substrate in the salt of solution with the small amount of nitric acid existed in it. CONSTITUTION:A porous sintered substrate is immersed in sp. gr. 1.73 molten nickel nitrate melted at, for example, 75 deg.C, and taken out, and dried by heating. The dried substrate is immersed in causitic soda solution, and washed to complete one impregnation cycle. Before the second impregnation process is performed, 1g/l or less of nitric acid is added to molten nickel nitrate, then the same impregnation process is carried out. By repeating several cycles of impregnation process, the desired amount of active material is filled in the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION Conventionally, a porous sintered substrate is immersed in a dilute aqueous solution of nickel nitrate or cadmium nitrate, followed by heat treatment, immersion treatment in an alkaline bath solution, washing with water, and drying for 8 to 10 days. Repeat step B "Fill the pre-prepared active material with Roku Alka IJ"
? J', 'Tunikegawa electrode plates had been manufactured, but this process was industrially disadvantageous because the process required many repetitions. It has been proposed to use a molten salt of cadmium or a highly concentrated aqueous solution to eliminate the disadvantage of It is possible, but the second time b #)>I
In the S L, the alkali content remaining in the substrate (-7) is the same as that of the 1tl salt or the water soluble water with a high E degree:
The impregnating liquid becomes a viscous liquid, which has the disadvantage of decreasing filling properties.

The present invention eliminates these drawbacks and improves the true efficiency of the i4j for alkaline synthesis ponds. This method provides a multi-hole f/l method.
'Jrm molten tk of nickel or cadmium nitrate';;J
'Akimata T', high lj5 water fr; * immersion, heat immersion
! 1! , alkaline water 7'? −i′? r′1. The filling process consists of edge τ, shi'+'+I↑ treatment, washing with water, and drying, ll
j to I r demon 1 same number shi・”1′・repeat alkaline storage 11
．． In the method for manufacturing holly boards for ponds, the molten salt or high +7''
The presence of (+i) nitric acid in the water bath solution (4ji) is considered to be porous 1'l: j+!: 9z immersion ↑). do.

Next, we will explain theory 1] for one example of non-inventive implementation.

Ratio L obtained by melting a porous sintered substrate (porosity 80%) made by sintering carbonyl niracle powder at approximately 900°C at 175°C.
[(1,73 immersed in molten salt of Niracle nitrate for 20 minutes,
Next, heat dry at 90"C (1) temperature and dry the dried substrate for 2
One filling process is completed by immersing in a 5% caustic soda aqueous solution for 30 minutes, washing with water, and drying. When performing the second filling process, nitric acid is added in advance to the nickel nitrate molten salt. Then, the substrate that has undergone one filling process described in B11 is immersed in a nickel nitrate molten salt that uniformly contains fl'I acid at a concentration of 19/l or less and contains a small amount of nitric acid. Soak for 20 minutes. In such cases, the caustic soda remaining in the substrate due to insufficient water washing is neutralized with a portion of the nitric acid, creating pores impregnated with molten salt in its wake, and the caustic soda reacts with the nitrate to cause hydroxide. This prevents the viscosity from increasing, and furthermore, the hydroxide is dissolved by the nitric acid and returned to nitrate, and as a whole, it helps to maintain the salt impregnation in a good manner. .

In this way, the process was repeated in the same way (11j L, 4 times, and the light filling of the active material of the required fence was completed in the filling process. For comparison,
? When filling was carried out using the conventional method of making V without adding itj acid, six optical filling operations were required to carry out illegal filling of R9. The results are shown in attached figure 1 “1”.
) not shown. In the drawing, it: 66 illegal lines,
11 is a conventional method of light Jj! Show the curve.

As a result of many U) experiments and (t) 1 investigation, 61JIi (
1)? i! Iku1b1( is its bath molten salt or 1(,
It is preferable that the water bath solution has a concentration of 5 to 1 to 19 degrees.

While repeating the above filling process, add nitric acid to the original 11. It is 16th to make sure that it holds. The above nitric acid CIJ2 nickel cloth hU; instead of salt,
The same effect can be obtained by applying the illegal method to the aqueous solution of the same concentration, and the nickel electrode plate is applied four times to the J1. th and i)・
I was able to build 14. Also, regarding the promotion of cadmium pole, f
In the case of impregnation with iam cadmium solution 1: salt or an aqueous solution of high concentration, a similar effect was observed when the method was applied.

As described above, according to the present invention, a melt of nitrate such as nickel nitrate or cadmium nitrate or a highly concentrated aqueous solution thereof is used to treat a nickel electrode plate or a cadmium electrode plate, and a small amount of nitric acid is added to the melt. Since the filling process is carried out in a state in which .

[Brief explanation of drawings]

The drawing shows a comparative diagram of the filling characteristics of illegal and conventional methods. I...Illegal filling curve ■・・・Conventional filling curve Special C′ [Applicant: Furukawa Battery Co., Ltd. Representative Kita '41] Kin - 712 people Full-scale Ususa Mekoku

Claims (1)

[Claims] 1. A porous substrate is prepared by immersion in a molten salt or high-temperature aqueous solution of nickel nitrate or cadmium nitrate, heat treatment, immersion in an alkaline water bath, washing with water, and drying. In the method of manufacturing electrode plates for alkaline storage batteries, which repeats the process a required number of times, nitric acid is added to the molten salt or highly concentrated water, and a porous substrate is formed in a state where a small amount of nitric acid is soaked. A method for manufacturing an electrode plate for an alkaline storage battery, characterized in that the nitric acid is added in an amount of about 0.1 to 1 per high-concentration aqueous solution. Special feature a' ``The manufacturing method described in item (1) for the scope of the front vehicle.