JP3475803B2 - Alkaline batteries - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkaline dry battery, and more particularly to an alkaline dry battery having a feature in a base paper for separators. 2. Description of the Related Art Normally, AA or other alkaline batteries 1
For example, as shown in FIG. 1, a conductive film (not shown) made of carbon or the like is formed on an inner surface of a bottomed cylindrical positive electrode can 2, and three cylindrically formed positive electrode cans 2 are formed in the positive electrode can 2. The positive electrode mixture 3 is accommodated, a bottomed cylindrical separator 4 is inserted inside the positive electrode mixture 3, and an electrolytic solution is infiltrated into the separator 4 and the positive electrode mixture 3, and a gel is formed in a hollow portion of the separator 4. The zinc anode 5 is filled. [0003] A sealing body 6 is attached to the opening of the positive electrode can 2. That is, in the sealing body 6, the current collector 8 is fixed to the inner central portion of the negative electrode terminal 7 by spot welding or the like, and the gasket 9 is fitted into the current collector 8 with the sealant 10 interposed therebetween and fastened by the sealing cap 11. It is configured. Then, while the current collector 8 is inserted into the gelled zinc negative electrode 5 and the tip 4A of the separator 4 is pressed by the gasket 9 and bent inward, the opening-side end of the positive electrode can 2 is Gasket 9 caulked inside
Is clamped between the outer peripheral portion of the negative electrode terminal 7 and the end of the positive electrode can 2 so that the sealing body 6
Opening is sealed. [0004] A label 12 is wound around the outside of the positive electrode can 2. Outer periphery of negative electrode terminal 7 and label 12
And an annular negative-side washer 13 is interposed therebetween. Conventionally, as shown in FIG. 2, a separator base paper 21 wound in a roll is rotated in the vertical direction and drawn out in a longitudinal direction to cut the separator base paper 21 into a predetermined size. , And wound in a cylindrical shape by rotating in the horizontal direction, and then the body and the bottom are heat-sealed to form a bottomed cylindrical shape. The manufacturing method of such a separator 4 is such that the moving direction of the separator base paper 2 is set to 90 when the process is shifted from the cutting process to the cylindrical winding process.
Since it was necessary to change the direction, it took a long time, and it was possible to manufacture only at a manufacturing speed of about 100 pieces per minute. For this reason, the separator 4 is set at 600
In the case of manufacturing about pieces, as shown in FIG. 3, the separator base paper 21 wound in a roll is rotated in the horizontal direction and drawn out in the longitudinal direction, cut into a predetermined size, and then the separator base paper 21 is cut with a mandrel. Similarly, it is rotated in the horizontal direction and wound into a cylindrical shape, and then the body and the bottom are heat-sealed to form a bottomed cylindrical shape. In this way, it is not necessary to change the moving direction of the separator base paper 21 when moving from the cutting step to the cylindrical winding step, so that the production speed can be increased. However, when the separator base paper 21 is rotated in the horizontal direction, drawn out in the longitudinal direction, cut into a predetermined size, and then similarly horizontally rotated and wound into a cylindrical shape, a cylindrical shape is obtained. Since the axial direction of the separator 4 coincides with the width direction of the separator base paper 21, when the gasket 9 of the sealing body 6 presses the distal end portion 4A of the separator 4 and bends inward in the radial direction, buckling may occur. there were. When such buckling occurs, the alkaline dry battery 1
However, when vibration or impact is applied, the gelled zinc negative electrode 5 moves from the space between the separator 4 and the gasket 9 to the positive electrode mixture 3 side, and there is a problem that an internal short circuit is easily caused. The present invention has been made in view of the above circumstances, and is configured to rotate a separator base paper wound in a roll shape in a horizontal direction, draw out the separator base paper to a predetermined size, and then rotate the separator base paper in a horizontal direction. Even when the tip of the separator having the formed cylindrical portion is bent inward in the radial direction by the gasket of the sealing body, buckling of the tip of the separator can be prevented, and vibration or impact is applied. It is an object of the present invention to provide an alkaline dry battery capable of preventing an internal short circuit from occurring. [0009] In order to achieve the above object, an alkaline dry battery according to the present invention according to claim 1 comprises:
A positive electrode mixture formed into a cylindrical shape is stored in a bottomed cylindrical positive electrode can, and the tensile strength in the longitudinal direction is placed inside the positive electrode mixture.
The separator base paper wound in a roll shape at a ratio of tensile strength in the width direction of 2/1 to 1.1 / 1 is rotated in the horizontal direction, pulled out, and cut into a predetermined size. A separator having a cylindrical portion formed by rotating the separator base paper in the horizontal direction is inserted, an electrolytic solution is infiltrated into the separator and the positive electrode mixture, and the hollow portion of the separator is filled with a gelled zinc negative electrode. In an alkaline dry battery in which a sealing body is attached to the opening of the positive electrode can and the tip of the separator is bent inward in the radial direction by the gasket of the sealing body, the width in the width direction of the separator base paper is pulled.
The strength is not less than 2.2 kg . Here, the above-mentioned separator having a cylindrical portion is a concept including a cylindrical separator, a cylindrical separator having a bottom outer peripheral portion, and a bottomed cylindrical separator. That is, although the separator 4 is formed in a bottomed cylindrical shape, the separator 4 is formed in a cylindrical shape or a cylindrical shape having a bottom outer peripheral portion, and a bottom cup is used in the bottom portion or the bottom central portion. Alternatively, a separate separator may be used, or a hot melt resin or the like may be used. In the first aspect of the present invention, the separation
The raw paper has a fiber orientation, and its longitudinal tension
The ratio between the strength and the tensile strength in the width direction is 2/1 to 1.1 / 1.
At least 2.2kg of tensile strength in width direction
To ensure that the separator base paper wound in a roll shape is rotated in the horizontal direction, pulled out, cut into a predetermined size, and then the separator base paper is rotated in the horizontal direction. Even in a structure in which the sealing member is bent inward in the radial direction by the gasket, the tip portion of the separator does not buckle. Therefore, even when vibration or impact is applied, no internal short circuit occurs. As a result, the production speed of the separator and, consequently, the production speed of the alkaline dry battery can be improved without causing product defects. An embodiment performed to confirm the effects of the present invention will be described below. (Example 1) First, the AA alkaline battery 1 shown in FIG. 1 was manufactured as follows. Electrolytic manganese dioxide 9
2% by weight, 5% by weight of graphite and 2.5% of 40% potassium hydroxide
After sieving the positive electrode mixture powder obtained by mixing 0.5% by weight of the binder and 0.5% by weight of the binder, the mixture is molded into a cylindrical shape to produce a positive electrode mixture 3,
Three pieces were housed in the bottomed cylindrical positive electrode can 2. Next, the separator 4 was inserted into the positive electrode mixture 3. As shown in FIG. 3, the separator 4 is formed by rotating a separator base paper 21 formed of vinylon fiber / rayon fiber / vinylon binder and having a thickness of 120 μm and a width of 56 mm, in a horizontal direction. Then, it is pulled out in the longitudinal direction and cut into a square of 81 mm in length and 56 mm in width. Thereafter, the separator base paper 21 is similarly horizontally rotated by a mandrel and wound three times in a cylindrical shape.
Thereafter, the body and the bottom were heat-sealed to form a bottomed cylinder having an outer shape of 8.8 mm and a height of 48 mm. The separator base paper 21 was subjected to a tensile test of a rectangular piece having a longitudinal direction of 200 mm and a width of 15 mm. As a result, the tensile strength in the longitudinal direction and the tensile strength in the width direction were 4.5 kg and 3.0 kg, respectively.
The ratio was 1.5 / 1. Next, 1.1 ml of a 40% aqueous solution of potassium hydroxide was injected into the separator 4 and a predetermined aging time was allowed to elapse in order to wet the separator 4 and the positive electrode mixture 3. Next, zinc powder 68% by weight, polyacrylic acid 0.4% by weight, zinc oxide 1.1% by weight, 40%
A gel zinc negative electrode 5 prepared from 30.5% by weight of an aqueous potassium hydroxide solution was filled in the hollow portion of the separator. Next, the current collector 8 is inserted into the gelled zinc negative electrode 5, and the end 4 A 4 mm of the separator 4 is pressed by the gasket 9 and bent inward. The inside of the positive electrode can 2 was sealed by the sealing body 6 by tightening the inner side of the gasket 9 between the outer periphery of the negative electrode terminal 7 and the end of the positive electrode can 2. Next, a negative electrode terminal 7 is provided outside the positive electrode can 2.
The label 12 was wound with an annular negative-side washer 13 interposed between the outer peripheral portion of the outer side and the label 12. Next, the alkaline dry battery 1 manufactured in this manner is loaded with the negative electrode terminal 7 side downward at an acceleration of 500 G.
After dropping 0 pieces, the presence or absence of an internal short circuit after dropping was examined. As a result, there was no internal short circuit in all 50 pieces. (Example 2) As a result of a tensile test of a square piece having a length of 200 mm and a width of 15 mm as the separator base paper 21, the tensile strength in the longitudinal direction and the tensile strength in the width direction were 4.5 kg, 2 kg, respectively. It was manufactured in the same manner as in Example 1 except that the weight was 0.2 kg and the ratio was 2.0 / 1, and a drop test was performed. As a result, there was no internal short circuit in all 50 pieces. (Example 3) As a result of a tensile test of a square piece having a length of 200 mm and a width of 15 mm as the separator base paper 21, the tensile strength in the longitudinal direction and the tensile strength in the width direction were 4.5 kg, 3 kg, respectively. It was manufactured in the same manner as in Example 1 except that a material having a ratio of 0.6 kg and a ratio of 1.1 / 1 was used, and a drop test was performed. As a result, there was no internal short circuit in all 50 pieces. (Comparative Example 1) As Comparative Example 1, as shown in FIG. 2, a separator base paper 21 wound in a roll is rotated in the vertical direction, drawn out in the longitudinal direction, cut, and then cut. The separator 4 is manufactured into a cylindrical shape with a bottom by rotating the mandrel in the horizontal direction and winding it into a cylindrical shape, and then by fusing the body and the bottom with heat, and the separator base paper 21 has a length of 200 mm and a width of 15 mm. As a result of the tensile test of the square piece, the tensile strength in the longitudinal direction and the tensile strength in the width direction were each 4.5.
kg, 1.7 kg, and a ratio of 2.7 / 1 was used in the same manner as in Example 1, except that a drop test was performed. As a result, there was no internal short circuit in all 50 pieces. (Comparative Example 2) The above separator base paper 2
As a result, as a result of a tensile test of a square piece having a length of 200 mm and a width of 15 mm, the tensile strength in the longitudinal direction and the tensile strength in the width direction were 4.5 kg and 1.7 kg, respectively.
A drop test was performed in the same manner as in Example 1, except that the ratio was 2.7 / 1. As a result, 5
An internal short circuit occurred in seven of the 0 pieces. As a result, when the separator 4 was manufactured by the method shown in FIG. 2 as in Comparative Example 1, the ratio of the tensile strength in the longitudinal direction to the tensile strength in the width direction of the separator base paper 21 was less than 2. Even if it is large, an internal short circuit does not occur, but when the separator 4 is manufactured by the method shown in FIG. 3 as in Comparative Example 2, the tensile strength in the longitudinal direction and the tensile strength in the width direction of the separator base paper 21 are reduced. It was confirmed that when the ratio was greater than 2, an internal short circuit occurred, whereas when the ratio was 2 or less, no internal short circuit occurred. As described above, in the alkaline dry battery according to the first aspect of the present invention, the separator
Paper has fiber orientation, its tensile strength in the longitudinal direction and
The ratio of the tensile strength in the width direction is 2/1 to 1.1 / 1,
Also ensure that the tensile strength in the width direction is at least 2.2 kg.
Is therefore, after cutting the drawer predetermined size by rotating the separator base paper is wound into a roll in the horizontal direction, the leading end portion of the separator having a cylindrical portion formed by rotating the separator sheet in the horizontal direction, the sealing Even in a structure that is bent inward in the radial direction by the body gasket, buckling of the separator tip can be prevented, so that an internal short circuit can be prevented even when vibration or shock is applied. it can. Therefore, the production speed of the separator, and hence the production speed of the alkaline dry battery, can be improved without causing product defects.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of an alkaline dry battery according to the present invention. FIG. 2 is a process chart for explaining a conventional separator manufacturing method. FIG. 3 is a process chart for explaining a method of manufacturing a separator according to the present invention. [Description of Signs] 1 Alkaline battery 2 Positive electrode can 3 Positive electrode mixture 4 Separator 4A Separator tip 5 Gelled zinc negative electrode 6 Sealing body 9 Gasket 21 Separator base paper

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-57-44974 (JP, A) JP-A-58-82465 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 6/00-6/12 H01M 2/14-2/18

Claims (1)

(57) [Claims 1] A positive electrode mixture formed into a cylindrical shape is housed in a cylindrical positive electrode can with a bottom, and a longitudinal direction is placed inside the positive electrode mixture.
The ratio of the tensile strength in the width direction to the tensile strength in the width direction is 2/1 to 1
After the separator base paper wound in a roll shape at 1.1 / 1 is horizontally rotated and pulled out and cut into a predetermined size, a separator having a cylindrical portion formed by rotating the separator base paper in the horizontal direction is inserted. An electrolyte is infiltrated into the separator and the positive electrode mixture, a gelled zinc negative electrode is filled in a hollow portion of the separator, a sealing body is attached to an opening of the positive electrode can, and the sealing body is In the alkaline dry battery in which the tip of the separator is bent inward in the radial direction by a gasket, the tensile strength of the separator base paper in the width direction is 2.2 kg.
Alkaline batteries, characterized in that at least.