JPS58123666A - Cylindrical alkaline battery - Google Patents

Abstract

PURPOSE:To prevent any breakage and deformation of a positive terminal part, which might be caused when positive mixtures are packed into a positive can, by packing a positive mixture into the positive terminal part which is provided by protruding the center of the base of the positive can. CONSTITUTION:After the central part of the bottom of a positive can 1 is protruded so as to make a positive terminal part 2, an appropriate amount of a positive mixture is packed into the positive terminal part 2, and pressed so as to make a positive mixture layer 3b. Then, temporarily-molded ring-like positive mixtures 3c are stacked in the positive can 1. Next, a core rod 21 is fitted into the hollow center of the positive mixtures 3c, and the mixtures 3c are pressed from above with an upper pounder 22 so as to make the positive can 1 and the positive mixtures 3c in close contact with each other. After that, a separator 5 and a negative agent 4 are packed in the hollow center so as to constitute a cylindrical alkaline battery. Consequently, since the positive mixture 3b exists in the positive terminal part 2, the strength of the terminal part 2 is increased, and any breakage and deformation of the battery can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to cylindrical alkaline batteries, such as alkaline manganese batteries.

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 center of the positive electrode mixture, and an upper punch slidably attached to the outer circumference of the core rod applies pressure from the top of the positive electrode mixture to compress the IE version mixture between the positive electrode can and the core rod. However, when the positive electrode terminal is provided at the bottom of the positive electrode can as described above, the tip of the core rod (21) is attached to the inner wall of the positive electrode can as shown in FIG. Since the positive electrode mixture (8c) is compressed while in contact with the periphery of the positive electrode terminal (2), all the pressure applied to the core rod 12I) is transferred to the positive electrode terminal (2).
As a result, the positive electrode terminal portion (2) may be deformed, resulting in 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 reduces the current collection area. This is an attempt to increase the number of people.

In the present invention, filling the positive electrode mixture into the positive electrode terminal section is carried out by filling the positive electrode can with granular or powdered positive electrode mixture in an amount sufficient to fill the positive electrode terminal section [7. As shown in Figure 5, it is possible to literally fill only the positive electrode terminal section (2), or fill the positive electrode can with a slightly larger amount of positive electrode mixture than can be filled into the positive terminal section, pressurize it, and then fill the positive electrode mixture into the positive electrode can. As shown in FIG. 8, the positive electrode mixture (8b) may be spread over the entire bottom of the positive electrode can (1) including the positive electrode terminal portion (2). The above-mentioned effect can be sufficiently exhibited by filling the positive electrode mixture only in the positive electrode terminal part as in the former case, but it is difficult in practice to fill the positive electrode mixture only in the positive electrode terminal part. As in the latter case, it is preferable to fill the entire bottom of the positive electrode can, including the positive electrode terminal, with the positive electrode mixture. Then, after filling the positive electrode mixture into the positive electrode terminal, fill it in a ring shape as in the conventional case. The temporarily formed positive electrode mixture is stacked along the inner wall of the positive electrode can, a core rod is inserted into the hollow part of the ring-shaped positive electrode mixture, and pressure is applied from the top of the positive N mixture with an upper punch to form the positive electrode mixture. This can be done by compressing it between the positive electrode can and the core rod and bringing it 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.

(2) is a positive terminal portion formed by protruding the center portion of the bottom of the positive electrode can (1). (3) is 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 vinylon-rayon mixture placed between the positive electrode mixture (3) and the negative electrode material (4). A separator made of paper, etc. (6) is a negative electrode lead rod, (7) is a sealing body that seals the opening of the positive electrode can (1), and this sealing body (
7) is the thick part formed around the through hole through which the negative i 1J rod (6) is inserted, and the opening of the positive electrode can (1).
One part is composed of an outer peripheral edge that is in contact with the inner peripheral surface of the peripheral wall, 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, and the through hole has a negative electrode lead. A rod (6) is inserted, and an annular support (8) made of iron having a ventilation hole is fitted between the thick part and the outer peripheral edge. A groove for receiving the sealing body (7) is provided near the open end of the positive electrode can (1), and one end of the outer peripheral edge of the sealing body (7) is in contact with the bottom wall of the groove, and the positive electrode The portion of the can (1) beyond the groove is tightened inward and curved so that its inner peripheral surface is pressed against the outer peripheral edge of the sealing body (7), thereby sealing the positive electrode can (1).

(9) is a leaf spring disposed between the negative 4 lead rod (6) and the negative terminal plate (10), and this leaf spring (9) has its central part connected to the head of the negative electrode lead rod (6). is pressed, and its peripheral edge is in contact with the negative electrode terminal plate 01. (l is the positive electrode can (1
) and the negative terminal plate 01, an insulating ring (
1 is a resin tube, 04) is a metal exterior can, and αQ is a resin ring.

This battery is manufactured, for example, as shown below.

First, as shown in Figure 2, the positive electrode can (1) is placed in the mold (A).
Mix 85 parts of manganese dioxide (by weight, the same applies below), 12 parts of phosphorous graphite, and 3 parts of alkaline electrolyte with a concentration of 30% (by weight, the same applies below) in the positive electrode can (1). A granular positive electrode mix (8a) 0.49 g of the positive electrode mixture (8a) is filled with the positive electrode can (1), and the positive electrode can (1 ) A layer of pressurized positive electrode mixture (3b) is formed on the bottom of the electrode.

Next, as shown in FIG. 4, four cathode mixtures (3c) temporarily formed into a ring shape with the same composition as above are stacked along the inner wall of the cathode can (2), and the ring-shaped cathode mixture (3c) is stacked along the inner wall of the cathode can (2). (3c) The core rod el) f is inserted into the hollow part, and the tip of the core rod a is brought into contact with the positive electrode mixture (3b) layer formed at the bottom of the positive electrode can (1), and is slid onto the outer periphery of the core rod [F]η. A ring-shaped positive electrode mixture (
3c) is pressurized from above at a pressure of l Q t /z2 to compress the positive electrode mixture between the positive electrode can (1) and the core rod f2 and bring it into close contact with the inner wall of the positive electrode can (1).

Next, after extracting the upper punch (A) and core rod e2Dk from the positive electrode can (1), the separator (5) and negative electrode material (4) are loaded into the hollow part of the positive electrode mixture, and thereafter, the Assemble the battery as shown in Figure 1.

The periphery of the positive electrode terminal of the positive electrode can of a conventional battery of the same type, which was manufactured without filling the LROB type battery type electrode terminal of the present invention with the positive electrode mixture obtained as described above, was 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.

As shown in Table 1, the battery of the present invention has fewer defects due to cracking, tearing, etc. than conventional batteries.

-11 According to the present invention, by filling the positive electrode terminal with a 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 becomes dented during use. It also has the effect of preventing such problems.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the cylindrical alkaline battery of the present invention, and FIGS. 2 to 4 are partial cross-sectional views during the main steps of manufacturing the battery shown in FIG. FIG. 5 is a partial sectional view during the manufacturing process of another embodiment of the cylindrical alkaline battery of the present invention, and FIG. 6 is a partial sectional view during the manufacturing process of a conventional battery. (1)...Positive electrode can, (2)...Positive electrode terminal, (3)
---Cathode mixture patent applicant Hitachi Maxell, Ltd.

Claims (1)

[Claims] 1. A cylindrical alkaline battery characterized in that a positive electrode terminal portion formed by protruding the bottom center of a positive electrode can is filled with a positive electrode mixture.