JPH0465500B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improvement in the manufacturing method of a cylindrical alkaline battery, and aims to shorten manufacturing time by promoting infiltration of an electrolytic solution into a positive electrode mixture, and to improve battery characteristics. In cylindrical alkaline batteries such as cylindrical alkaline and manganese batteries, a separator processed into a pot is inserted into the hollow part of the cylindrical positive electrode mixture, and an electrolyte is injected into the hollow part of the separator to separate the separator and the positive electrode. A method has been adopted in which the positive electrode mixture is infiltrated with an electrolytic solution while the mixture is made to adhere closely. By the way, when using such a method, the outer diameter of the separator is designed to be slightly smaller than the inner diameter of the positive electrode mixture in order to facilitate insertion of the separator into the hollow part of the positive electrode mixture, and the separator is designed to be shaped like a tap. Due to dimensional variations during processing, gaps tend to form between the positive electrode mixture and the separator, which slows down the electrolyte injected into the separator and infiltrates the positive electrode mixture, resulting in longer manufacturing times. There were problems such as longer battery life and deterioration of battery characteristics. The present invention solves the above-mentioned drawbacks of the prior art, and when press-bonding the positive electrode mixture to the positive electrode can, a porous body having a liquid retaining property is interposed between the positive electrode mixture and the core rod. Pressure is applied from above and the positive electrode mixture is crimped onto the positive electrode can, then the core rod is pulled out and the hollow separator of the cylindrical part formed by the porous body is inserted to prevent the electrolyte from infiltrating into the positive electrode mixture. The purpose was achieved by promoting the battery and improving battery characteristics. That is, according to the method of the present invention, the positive electrode mixture also comes into pressure contact with the porous body due to the pressurization, and the mixture particles enter the pores of the porous body, so that the adhesion with the porous body is sufficient. In addition, the adhesion between the separator and the porous body is very good because the electrolyte injected into the separator causes the separator and the porous body to swell and come into close contact with each other. As a result, the gap between the positive electrode mixture and the separator is eliminated, and as a result, the infiltration rate of the electrolyte becomes faster, and the ionic conduction between the positive electrode mixture and the separator improves, reducing internal resistance. and improves heavy load characteristics. Porous materials having liquid-retentive properties used in the present invention include, for example, vinylon-rayon mixed paper, vinylon non-woven fabric, rayon non-woven fabric, mercerized cotton non-woven fabric, polypropylene non-woven fabric, polyamide non-woven fabric, vinylon non-woven fabric, vinylon-mercerized cotton mixed paper, mercer. Non-woven fabric made from treated pulp, linter pulp rayon mixed paper, etc. are used. It is preferable that these porous bodies be made of the same material as the separator. In addition, those that do not have liquid retention properties require a longer time for electrolyte to infiltrate.
It is also undesirable because it causes an increase in internal resistance. Next, embodiments of the present invention will be described with reference to the drawings. Example: In a nickel-plated iron positive electrode can 1, four ring-shaped positive electrode mixture molded bodies made by pressure-molding positive electrode mixture powder made of manganese dioxide and graphite are stacked and stored along the inner wall of the positive electrode can 1. Then, a pot 2 having a cylindrical part made of vinylon-rayon mixed paper with a thickness of 0.10 mm as a porous body was inserted into the hollow part of the positive electrode mixture along the inner wall of the hollow part of the positive electrode mixture. Then, the core rod 21 is inserted along the inner wall of the hollow part of the tip 2, and the core rod 21 is
A punch 22 slidably attached to the outer periphery of the can was lowered to apply pressure to the positive electrode mixture from above, thereby pressurizing the positive electrode mixture 3 to the inner wall of the positive electrode can 1 (see FIG. 1). After crimping, pull up the punch 22, then pull out the core rod 21, bend the opening of the positive electrode can 1, form a groove near the opening end, and then insert the vinylon-rayon mixed paper as the porous body into a cylindrical part. A thickness of 0.15 mm is placed in the hollow part of the pot-like object 2 called 2a.
A cylindrical separator 4 made by wrapping vinylon-rayon mixed paper three times is inserted, and then excess electrolyte 17 is injected into the separator 4 (see Figure 2), and left for 30 minutes to dissolve the electrolyte. was infiltrated into the separator 4, positive electrode mixture 3, etc. Thereafter, excess electrolyte was removed from the separator 4 using a suction nozzle. The amount of electrolyte infiltrated in 30 minutes was 1.7 g. Next, the separator 4 of the positive electrode can 1 is filled with a negative electrode material 5 in which zinc chloride powder is dispersed in an electrolytic solution, and then the synthetic resin sealing body 8 to which the negative electrode lead rod 6 and washer 7 are attached is attached to the positive electrode can 1. insert it into the opening of
The opening of the positive electrode can 1 was sealed by tightening the portion of the positive electrode can 1 beyond the groove in the radial direction to bring it into close contact with the sealing body 8. Thereafter, the exterior was applied by a conventional method to produce an LR6 type alkaline manganese battery A as shown in Fig. 3. In Fig. 3, 9 is a leaf spring, 10 is a negative terminal plate, 11 is an insulating ring, 12 and 13 are resin tubes, 14 is a positive terminal plate, 15 is a metal exterior can,
16 is an insulating ring. Comparative Example In the same positive electrode can 1 as in the example, four ring-shaped positive electrode mixture molded bodies obtained by pressure-molding the positive electrode mixture powder with the same composition as in the example were stacked and stored in the same manner as in the example. A core rod 21 is inserted into the hollow part, and a punch 2 is slidably attached to the outer periphery of the core rod 21.
2 was lowered to pressurize the positive electrode mixture from above, and the positive electrode mixture 3 was pressed onto the inner wall of the positive electrode can 1 (see FIG. 4). After crimping, pull up the punch 22, then pull out the core rod 21, bend the opening of the positive electrode can 1, form a groove near the opening end, and then insert a cylindrical part into the hollow part of the positive electrode mixture 3. Insert a pot-shaped separator 4 formed by wrapping 0.15 mm vinylon-rayon mixed paper in three layers, inject excess electrolyte into the separator 4, and leave it for 45 minutes to distribute the electrolyte between the separator 4 and the positive electrode. Mixture 3 was infiltrated. Thereafter, excess electrolyte was removed from the separator 4 using a suction nozzle. The amount of electrolyte infiltrated in 45 minutes was 1.6 g. Thereafter, LR6 type alkaline manganese battery B was manufactured according to a conventional method. Table 1 shows the time required for infiltration and the amount of electrolyte infiltrated in Batteries A and B manufactured as described above. Also, the internal resistance of batteries A and B and -10℃, 2Ω intermittent discharge (5 seconds discharge/5 seconds rest)
Table 2 shows the results of measuring the discharge time (net discharge time) to the final voltage of 0.9V.

【table】

[Table] As shown in Tables 1 and 2, the battery A manufactured by the method of the present invention requires a short time for infiltration of the electrolyte and has excellent battery characteristics. In the example, vinylon-rayon mixed paper as a porous body was inserted into the hollow part of the positive electrode mixture, and then a core rod was inserted into the hollow part of the cylindrical part made of the vinylon-rayon mixed paper. Alternatively, the porous body may be attached to the core rod, and the porous body may be inserted into the hollow portion of the positive electrode mixture together with the core rod. In addition, in the example, the porous body was inserted into the hollow part of the positive electrode mixture in a pot-like state with a bottom provided at the bottom, but if a cylindrical separator with a bottom is used, the bottom may not necessarily be provided. Good too.

[Brief explanation of the drawing]

1 to 3 are views showing a cylindrical alkaline battery according to the present invention, FIGS. 1 and 2 are cross-sectional views showing the state during manufacture, and FIG. 3 is a partial cross-sectional view showing the state after manufacture. It is a diagram. 4 and 5 are views showing a conventional cylindrical alkaline battery, with FIG. 4 being a cross-sectional view showing the state during manufacture, and FIG. 5 being a partial cross-sectional view showing the state after manufacture. DESCRIPTION OF SYMBOLS 1... Positive electrode can, 2a... Cylindrical part made of vinylon-rayon mixed paper as a porous body, 3... Positive electrode mixture, 4... Separator, 21... Core rod.

Claims (1)

[Claims] 1. A plurality of ring-shaped positive electrode mixtures are stacked along the inner wall of a positive electrode can, a porous body and a core rod having liquid retention properties are inserted into the hollow part of the positive electrode mixture, and the positive electrode mixture is formed into a ring shape. Pressurizing the positive electrode mixture from above with the porous body interposed between the agent and the core rod,
A method for producing a cylindrical alkaline battery, which comprises pressing a positive electrode mixture onto the inner wall of a positive electrode can, pulling out the core rod, and inserting a separator into the hollow part of the cylindrical part formed by the porous body. 2 The material of the porous body and separator is vinylon.
A method for producing a cylindrical alkaline battery according to claim 1, which is made of rayon mixed paper.