JPH0437546B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a cylindrical alkaline battery such as an alkaline manganese battery. Conventionally, in cylindrical alkaline batteries, the positive terminal plate was formed separately from the positive electrode can and attached to the bottom of the positive electrode can during assembly, but recently, from the perspective of reducing the number of parts, some batteries In this method, the center of the bottom of the positive electrode can is made to protrude to provide a terminal function. By the way, in cylindrical alkaline batteries, in order to make close contact between the positive electrode mixture and the positive electrode can, the positive electrode mixture is temporarily formed into a ring shape, and multiple pieces of this are stacked along the inner wall of the positive electrode can. A core rod is inserted into the hollow part of the positive electrode mixture, and pressure is applied from above the positive electrode mixture with an upper rod slidably attached to the outer periphery of the core rod to compress the positive electrode mixture between the positive electrode can and the core rod. Although the positive electrode terminal is placed in close contact with the inner wall of the positive electrode can, when the positive electrode terminal is provided at the bottom of the positive electrode can as described above, as shown in FIG.
Since the positive electrode mixture 3c is compressed with the tip of the core rod 21 in contact with the periphery of the positive electrode terminal 2, all the pressure applied to the core rod 21 is concentrated on the periphery of the positive electrode terminal 2, so that the periphery If a crack occurs in the positive electrode terminal part 2, or
may be deformed and cause dimensional defects. The present invention has been made in light of such circumstances, and by filling the positive electrode terminal portion formed by protruding the center portion of the bottom of the positive electrode can, the positive electrode mixture is compressed. In addition to preventing damage to the periphery of the positive electrode terminal and dimensional changes in the positive electrode terminal, it also increases the strength of the positive electrode terminal against external pressure and impact, and increases the filling amount of the positive electrode mixture and current collection area. This is an attempt to increase the number of people. To fill the positive electrode terminal with the positive electrode mixture, fill the positive electrode can with granular or powdered positive electrode mixture in an amount sufficient to fill the positive electrode terminal, pressurize it with a pressure member, and then press the positive electrode mixture into the positive electrode can.
As shown in the figure, it is possible to literally fill only the positive electrode terminal portion 2 with the positive electrode mixture, but it is difficult in practice to fill only the positive electrode terminal portion with the positive electrode mixture, so in the present invention, the positive electrode mixture is filled with the positive electrode terminal portion 2. Fill the positive electrode can with approximately 1,000 more positive electrode mixture than can be used, pressurize the positive electrode mixture, and as shown in FIG.
Make sure that the positive electrode mixture 3b is spread over the entire bottom of the tube. The above-mentioned effect can also be achieved by filling only the positive electrode terminal with the positive electrode mixture as in the former case, but it is difficult in practice to fill only the positive electrode terminal with the positive electrode mixture. In the present invention, as in the latter case, the entire bottom of the positive electrode can, including the positive electrode terminal portion, is filled with the positive electrode mixture. After filling the positive electrode terminal with the positive electrode mixture, as in the past, the temporarily formed ring-shaped positive electrode mixture is stacked along the inner wall of the positive electrode can, and the hollow part of the ring-shaped positive electrode mixture is stacked. The core rod is inserted into the positive electrode can, and pressure is applied from above the positive electrode mixture with an upper punch to compress the positive electrode mixture between the positive electrode can and the core rod, so that the positive electrode mixture is brought into close contact with the inner wall of the positive electrode can. Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial sectional view showing an example of a cylindrical alkaline battery manufactured according to the present invention. In the drawing, 1 is a positive electrode can, and 2 is a positive electrode terminal formed by protruding the bottom center of the positive electrode can 1. Department. Reference numeral 3 denotes a positive electrode mixture containing manganese dioxide as a main ingredient, and this positive electrode mixture 3 is also filled in the positive electrode terminal portion 2 . 4 is a negative electrode material made of amalgamated zinc as an active material and kneaded with an electrolyte, and 5 is a positive electrode mixture 3.
A separator made of vinylon-rayon mixed paper or the like is placed between the negative electrode material 4 and the negative electrode material 4. 6 is a negative electrode lead rod, 7 is a sealing body for sealing the opening of the positive electrode can 1, and this sealing body 7 has a thick part formed around the through hole through which the negative electrode lead rod 6 is inserted; It is composed of an outer peripheral edge that contacts the inner periphery of the opening peripheral wall of the positive electrode can 1, and a connecting part that has a V-shaped part and a thin wall part and connects the thick wall part and the outer peripheral edge. A negative electrode lead rod 6 is inserted, and an annular iron support 8 having a ventilation hole is fitted between the thick wall portion and the outer peripheral edge. And positive electrode can 1
A groove for receiving the sealing body 7 is provided near the open end of the groove, one end of the outer peripheral edge of the sealing body 7 abuts against the bottom wall of the groove, and the portion of the positive electrode can 1 beyond the groove is directed inward. It is tightened and bent so that its inner circumferential surface comes into pressure contact with the outer circumferential edge of the sealing body 7, and the positive electrode can 1 is sealed. Reference numeral 9 denotes a leaf spring disposed between the negative electrode lead rod 6 and the negative electrode terminal plate 10. This leaf spring 9 presses the head of the negative electrode lead rod 6 at its center, and presses the negative electrode terminal at its periphery. It is in contact with the plate 10. 11 is an insulating ring between the positive electrode can 1 and the negative electrode terminal plate 10; 12, 13;
14 is a resin tube, 14 is a metal exterior can, and 15 is a resin tube.
is a resin ring. This battery is manufactured, for example, as shown below. First, as shown in FIG. 2, the positive electrode can 1 is placed in a mold 2.
3, and in positive electrode can 1 85 parts of manganese dioxide (parts by weight, the same applies hereinafter), 12 parts of phosphorous graphite, and a concentration of 30%.
Filled with 0.4 g of granular positive electrode mixture 3a made by mixing 3 parts of alkaline electrolyte (wt%, same hereinafter),
Pressure is applied from above using the pressure member 24 to form a layer of the pressurized positive electrode mixture 3b on the bottom of the positive electrode can 1, including the positive electrode terminal portion 2, as shown in FIG. Next, as shown in FIG. 4, four cathode mixtures 3c having the same composition as above and temporarily formed into a ring shape are stacked along the inner wall of the cathode can 2, and the hollow part of the ring-shaped cathode mixture 3c is stacked. The core rod 21 is inserted into the positive electrode can 1, and the tip of the core rod 21 is brought into contact with the positive electrode mixture 3b layer formed on the bottom of the positive electrode can 1.
A pressure of 10 t/cm ² is applied from the top of the ring-shaped positive electrode mixture 3c by an upper punch 22 that is slidably attached to the outer circumference of the ring-shaped positive electrode mixture 3c, and the positive electrode mixture 3c is pushed between the positive electrode can 1 and the core rod 21. to make it tightly adhere to the inner wall of the positive electrode can 1. Next, after removing the upper punch 22 and the core rod 21 from the positive electrode can 1, the separator 5 and the negative electrode material 4 are loaded into the hollow part of the positive electrode mixture 3 (see FIG. 1) which has been integrated by the above-mentioned pressurization. Thereafter, a battery as shown in FIG. 1 is assembled according to a conventional method. The periphery of the positive terminal part of the positive electrode can of the LRO3 type battery of the present invention obtained as described above and a conventional battery of the same type manufactured without filling the positive terminal part with a positive electrode mixture were magnified 50 times with a microscope. The presence or absence of defects due to cracks, tears, etc. was observed. The results are shown in Table 1 below.

[Table] As shown in Table 1, the batteries manufactured according to the present invention (products of the present invention) have fewer defects due to cracking, tearing, etc. than batteries manufactured by the conventional method (conventional products). Further, according to the present invention, by filling the positive electrode terminal with the positive electrode mixture, the discharge capacity is improved, and the strength of the positive electrode terminal against external forces is improved, and the positive electrode terminal is not easily dented during use. It also has the effect of preventing such problems.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of a cylindrical alkaline battery manufactured according to the present invention, and FIGS. 2 to 4 are sections showing main steps in manufacturing the battery shown in FIG. FIG. 5 is a partial cross-sectional view during the manufacturing process of a cylindrical alkaline battery other than the present invention, and FIG. 6 is a partial cross-sectional view during the manufacturing process of a conventional battery. 1... Positive electrode can, 2... Positive electrode terminal section, 3... Positive electrode mixture,
3a... Granular positive electrode mixture, 3b... Pressurized positive electrode mixture, 3c... Ring-shaped positive electrode mixture, 4... Negative electrode material, 5
...Separator.

Claims (1)

[Claims] 1 In manufacturing a cylindrical alkaline battery having a positive electrode terminal portion 2 formed by protruding the center of the bottom of the positive electrode can 1, the positive electrode can 1 is filled with a granular or powdered positive electrode mixture 3a, and the positive electrode mixture 3a is applied from above. A layer of the pressurized positive electrode mixture 3b is formed on the bottom of the positive electrode can 1 including the positive electrode terminal portion 2, and then a positive electrode mixture 3c temporarily formed into a ring shape is laid on the inner wall of the positive electrode can 1. The core rod 21 is inserted into the hollow part of the ring-shaped positive electrode mixture 3c, and the tip of the core rod 21 is brought into contact with the layer of the pressurized positive electrode mixture 3b formed at the bottom of the positive electrode can 1. Pressure is applied from above the ring-shaped positive electrode mixture 3c with the upper rod 22 slidably attached to the outer periphery of the core rod 21.
c is compressed between the positive electrode can 1 and the core rod 21 so as to be brought into close contact with the inner wall of the positive electrode can 1, and the upper rod 22 and the core rod 21 are extracted from the positive electrode can 1.
A method for manufacturing a cylindrical alkaline battery, characterized in that the cylindrical alkaline battery is manufactured through the step of loading a separator 5 and a negative electrode material 4 into the hollow part of the positive electrode mixture 3 integrated by pressurization.