JP2000048782A - Cylindrical cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cylindrical cell to be surely held so as not to be detached even when a corner part of the cell is subjected to a strong impact while an insulation ring is fitted without using any adhesive. SOLUTION: A folded and caulked part 1a in which an opening part in a cylindrical cell case 1 is folded inwardly and caulked is pressed against a negative terminal plate 4 with a return part of an insulation sealing body interposed therebetween to tightly seal the opening part, and an insulation ring 14 abutted on an outer surface of the folded and caulked part 1a is held by the covering of a folded part 8a inward of an opening end of an external label 8 to cover an outer circumferential surface of the cell case 1. The outside diameter (r) of the insulation ring 14 is set to be smaller than the outside diameter of the cell case 1, i.e., the inside diameter R of the external label 8. The angle θ to be formed between a tangent in common contact with the outer circumferential end of the insulation ring 14 and the outer surface of the cell case 1 and the axis of the cell is set to be not less than 30 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical battery such as an alkaline dry battery, and more particularly, to a cylindrical battery case which is formed by crimping to seal an opening of a cylindrical battery case. The present invention relates to a cylindrical battery provided with an insulating ring.

[0002]

2. Description of the Related Art Cylindrical alkaline batteries, for example, alkaline dry batteries, are resistant to load and have low-temperature characteristics by using a strong alkaline solution such as a high-concentration potassium hydroxide aqueous solution having high ionic conductivity even at a low temperature as an electrolytic solution. Has good characteristics, and is therefore particularly awarded to devices requiring power such as motor driving. On the other hand, a strong alkaline solution used as an electrolytic solution is rich in permeability, so that it is likely to leak by so-called creeping, which penetrates even a small gap. Therefore, the alkaline dry battery has a sealing structure with high hermeticity, which will be described below.

FIG. 4 is a half vertical sectional view showing a sealing structure of a conventional alkaline battery. In FIG. 4, a rod-shaped negative electrode current collector 2 is provided at an opening of a bottomed cylindrical battery case (positive electrode) 1.
A resin sealing body (gasket) 3 is inserted into the insertion hole 3a by press-fitting, and a central portion of the negative electrode terminal plate 4 is electrically connected to the electrode portion 2a at the head of the negative electrode current collector 2 by welding. Connected to the state. The bent and swaged portion 1a formed by bending the bottom open end of the battery case 1 inward and crimping it strongly presses the folded portion 3b formed in the resin sealing body 3 against the negative electrode terminal plate 4. Then, the opening of the battery case 1 is sealed in a sealed state.

For example, in a device using a plurality of alkaline dry batteries connected in series, if one of the alkaline dry batteries is erroneously connected to the opposite polarity, the battery connected to the opposite polarity becomes adjacent. Being charged by the battery
A strong gas generating reaction occurs inside the battery. Since the alkaline dry battery has a sealing structure with high sealing properties as described above, the internal pressure of the battery increases, and when the internal pressure of the battery increases to a certain pressure or more, the explosion-proof thin portion 3c of the sealing body 3 becomes The gas in the battery case 1 is ruptured, and is discharged to the outside through the gas discharge hole 4a of the negative electrode terminal plate 4 from the hole generated by the rupture of the thin portion 3c. As a result, the battery is prevented from being ruptured due to an increase in battery internal pressure that exceeds the pressure resistance of the sealing structure.

Although the explosion-proof structure using only the thin portion 3c of the sealing body 3 and the gas discharge hole 4a of the negative electrode terminal plate 4 can prevent the battery from being ruptured, the strong alkaline electrolytic solution is used together with the gas. It cannot be prevented that the used equipment is damaged by spouting from the discharge hole 4a and scattering over a wide area, and the adhesion of the electrolytic solution. Therefore, conventionally, as shown in FIG. 4, an insulating ring 7 for preventing the electrolytic solution from escaping from the gas discharge hole 4a to the outside is disposed at a position where the gas discharge hole 4a can be shielded. 1
Is in contact with the outside of the crimped crimped portion 1a. The outer label 8 attached to the outer peripheral surface of the battery case 1 and then thermally shrunk to cover the battery case 1 is bent inward at the opening peripheral end thereof so as to cover the outer side of the insulating ring 7. The insulating ring 7 is attached to the side surface, and is covered and held by the bent portion 8 a of the outer label 8.

The insulating ring 7 has a function of preventing the battery case 1 serving as the positive electrode and the negative terminal plate 4 from being electrically short-circuited, in addition to the function of preventing the electrolyte solution from being ejected.

That is, in the battery of the type covered with the heat-shrinkable outer label 8 as described above, when friction or drop occurs during transportation of the battery, or when the used equipment is taken in and out of the battery storage box. In this case, peeling, cutting or breaking may occur at the bent portion 8a at the open end of the exterior label 8. In such a case, if the above-mentioned insulating ring 7 is not provided, the bent and swaged portion 1a of the battery case 1 and the negative electrode terminal plate 4, which are exposed due to breakage of the bent portion 8a of the outer label 8, are connected to the battery. At the time of loading and unloading, there is a possibility that the negative terminals formed of the coil springs of the used equipment come into contact with each other and are electrically connected through the negative terminals. If a short circuit occurs between the positive and negative sides of the battery in this way, the temperature of the battery will increase and the liquid will leak. Therefore,
Since the outer side surface of the bent and swaged portion 1a of the battery case 1 is shielded by the insulating ring 7, even if the bent portion 8a of the outer label 8 is broken or the like, the above-described short circuit between the positive and negative sides of the battery occurs. Can be prevented beforehand.

[0008]

However, the insulating ring 7 has an inner diameter of the outer label 8, that is, an outer diameter that is substantially equal to the outer diameter of the battery case 1, and is overlapped so as to cover the outer surface. Folded portion 8a of label 8
It is configured to be held only by adhesion and heat shrinkage. Therefore, for example, as shown in FIG. 4, when the battery falls in an inclined posture and its corner collides with some object 9, the insulating ring 7 receives a strong impact force directly and It may shift in the width direction, break through the outer label 8 and drop from the battery.

Further, the insulating ring 7 has a shape having an outer diameter substantially equal to the inner diameter of the outer label 8 as described above for the purpose of fixing the insulating ring 7 to the opening of the outer label 8 before forming the bent portion 8a by press-fitting means. Therefore, the step of press-fitting the exterior label 8 into the opening becomes difficult. For example, in the process of inserting the insulating ring 7 into the opening of the outer label 8, the insulating ring 7 may be inserted in a state of being in contact with and offset from the outer label 8, or may be deformed by pressing the outer label 8 from above. Failures such as poor appearance occur frequently, which lowers the yield.

[0010] Separately, by fixing the insulating ring 7 to the bent portion 1a of the battery case 1 with an adhesive,
A technique has been proposed for preventing the insulating ring 7 from falling off even when a strong impact force is received. However, this battery not only increases the material cost due to the use of an expensive adhesive, but also has a step of applying the adhesive to the bent portion 1a having a small area in the battery case 1, so that the productivity is increased. And the manufacturing cost increases, resulting in a considerable increase in cost. In addition, the adhesive may adhere to portions of the battery case 1 other than the crimped portion 1a. For example, when the adhesive adheres to the negative electrode terminal plate 4, Poor contact with the negative electrode terminal may occur, resulting in deterioration of the battery quality. Therefore, such a battery is difficult to put into practical use.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in consideration of the above-described problem. It is an object of the present invention to provide a cylindrical battery that can be securely held without falling off.

[0012]

In order to achieve the above object, the present invention provides a cylindrical battery case in which an opening in a cylindrical battery case is bent inward and swaged to form an insulative sealing body. By being pressed against the negative electrode terminal plate via the folded portion, the opening is hermetically sealed, and the insulating ring in contact with the outer surface of the bent-up portion covers the outer peripheral surface of the battery case. In the cylindrical battery held by covering the inwardly bent portion of the open end of the outer label, the outer diameter of the insulating ring is set smaller than the outer diameter of the battery case, and the outer peripheral end of the insulating ring and The angle between a tangent line commonly contacting the outer surface of the battery case and the axis of the battery is set to be 30 ° or more.

[0013] In this cylindrical battery, when it falls naturally and collides with a horizontal object in an inclined state in which the angle of the axis with respect to the vertical line is within 30 ° or less, the impact force received by the insulating ring increases the axial force of the battery. The component in the center direction, that is, the thickness direction of the insulating ring is almost the same, and the component in the width direction of the battery, that is, the radial direction of the insulating ring is small. On the other hand, when the axis falls at an angle of 30 ° or more and 90 ° or less with respect to the vertical line and collides with a horizontal object, the outer peripheral surface of the battery case collides with the object first, and the insulating ring Does not receive a large impact force. Therefore, without using an adhesive, the insulating ring has a structure in which a large impact force such as shifting in the width direction of the battery is not applied even if the insulating ring is held only by adhesion and heat shrinkage by the outer label, There is no danger of breaking through the outer label and falling off the battery.

Further, in this battery, since the outer diameter of the insulating ring is set smaller than the outer diameter of the battery case, that is, the inner diameter of the outer label, the insulating ring is inserted into the opening of the outer label during manufacture. The mounting process of contacting the bent and crimped portion of the case can be performed easily and promptly, and the appearance of the opening of the outer label is not deformed by the inserted insulating ring, and the appearance does not deteriorate.

In the above invention, the terminal surface on the outer side of the negative electrode terminal plate may be configured to be recessed inward from the outer surface of the bent portion of the outer label. With this, in a device that uses a plurality of batteries connected in series, if the battery is incorrectly set in the battery storage box in a reverse polarity arrangement,
The bent portions of the outer labels of the two adjacent batteries are in contact with each other, and the respective terminal surfaces of the respective negative electrode terminal plates cannot be in contact with each other. Therefore, the battery connected in reverse polarity is not charged by the adjacent battery, so even if the battery is left in the reverse connection state for a long time, the explosion-proof mechanism operates and the electrolyte leaks out of the battery case. And the expected life of the battery can be ensured.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a half longitudinal sectional view showing a cylindrical battery according to an embodiment of the present invention. In FIG. 1, the same reference numerals as those in FIG. Has the following configuration. That is, the headed cylindrical battery case 1 has a positive electrode terminal 10 protruding from an upper end surface thereof and an outer peripheral surface covered with a heat-shrinkable outer label 8 fixed by sticking and heat-shrinking means. I have. A positive electrode mixture 11 formed into a cylindrical shape with manganese dioxide and graphite added as a conductive material is inserted into the battery case 1. Inside the positive electrode mixture 11, a gelled zinc negative electrode 12 in which a zinc alloy powder is uniformly dispersed together with a gelling agent in an alkaline electrolyte in which potassium hydroxide is dissolved is injected via a separator 13. .

An opening at the bottom of the battery case 1 is closed by inserting a resin sealing body 3 in which a rod-shaped negative electrode current collector 2 made of brass is press-fitted into an insertion hole 3a.
Further, a negative electrode terminal plate 4 is fixed to the negative electrode current collector 2 in an electrically connected state by welding to the electrode portion 2a on the head thereof. The bottom opening end of the battery case 1 is bent inward and caulked, so that the bent caulked portion 1 is formed.
The folded portion 3b formed in the resin sealing body 3 is strongly pressed by the negative electrode terminal plate 4 in a, and the opening of the battery case 1 is sealed in a sealed state.

Further, the insulating ring 14 is brought into contact with the outer surface of the bent portion 1a of the battery case 1 in such a manner that the negative electrode terminal plate 4 is inserted into its inner hole, and the open end of the outer label 8 is inward. A bent portion 8a is adhered to the outer surface of the insulating ring 14, and the insulating ring 14 is fixed by the heat-shrinked bent portion 8a.
That is, the insulating ring 14 is held only by adhesion and heat shrinkage by the heat shrinkable outer label 8 without using an adhesive.

FIG. 2 is an explanatory view of the battery of the above embodiment. The outer diameter r of the insulating ring 14 is smaller than the outer diameter of the battery case 1, that is, the inner diameter R of the outer label 8, and is indicated by a broken line in FIG. The angle θ formed between a tangent line commonly contacting the outer peripheral end of the insulating ring 14 and the outer surface of the bent portion 1a of the battery case 1 with the axis of the battery (a straight line in the axial direction of the battery), that is, the axis of the battery Is set so that the elevation angle θ of the tangent to the angle is 30 ° or more.

In this battery, when the negative electrode terminal plate 4 falls downward and collides with a horizontal object by naturally falling in an inclined state in which the angle of the axis with respect to the vertical line is within 30 ° or less, Except when the angle is 0 °, the insulating ring 14
Corner of the outer peripheral end face first collides with the object, but since the angle θ at this time, that is, the angle θ between the radial direction of the insulating ring 14 and the horizontal collision surface is as small as 30 ° or less, the insulating ring 14 Most of the impact force applied to the battery is in the axial direction of the battery, that is, in the thickness direction of the insulating ring 14, and the component in the width direction of the battery, that is, the component in the radial direction of the insulating ring 14 is small. Therefore, despite the fact that the insulating ring 14 is only held by the adhesive and heat shrinkage of the exterior label 8 but does not receive a large impact force that shifts in the width direction of the battery, the exterior label 8 is There is no danger of breaking through and falling off the battery.

On the other hand, when the negative electrode terminal plate 4 faces downward and the angle of the axis with respect to the vertical
When the battery falls naturally and collides with a horizontal object in an inclined state of less than or equal to an angle of less than or equal to the angle, the outer peripheral surface of the battery case 1 collides with the object first, and a large impact force is not applied to the insulating ring 14. Therefore, the insulating ring 14 does not receive an impact force that shifts in the width direction of the battery, so that there is no possibility that the insulating ring 14 may break through the outer label 8 and fall off the battery. That is, even if the battery is dropped in any posture and collides with an object despite the fact that the insulating ring 14 is held only by adhesion and heat shrinkage by the outer label 8 without using an adhesive, In this structure, a large impact force such as breaking through the outer label 8 and falling off the insulating ring 14 is not applied.

In this battery, since the outer diameter r of the insulating ring 14 is set smaller than the outer diameter of the battery case 1, that is, the inner diameter of the outer label 8, the insulating ring 14 is connected to the opening of the outer label 8 during manufacturing. Attaching to the bent portion of the battery case 1 to make contact with the bent portion 1a of the battery case 1 can be performed easily and quickly, and the inserted insulating ring 14 is deformed into the opening of the exterior label 8 to cause poor appearance. There is no.

The following test was conducted to confirm the above effects. As a test battery according to the present invention,
The angle θ shown in FIG. 2, that is, the angle between the tangent line that is in contact with the outer peripheral end of the insulating ring 14 and the outer surface of the bent portion 1 a of the battery case 1 and the axis of the battery is 0 °, 10 °, respectively.
Using five types of insulating rings 14 having different outer diameters of 20 °, 30 °, and 45 °, these insulating rings 14
Without using an adhesive, 100 batteries each of five types of batteries each of which was fixed only by sticking with the outer label 8 and heat shrinkage were produced. The insertion of the insulating ring 14 into the opening of the exterior label 8 was performed using an automatic insertion machine developed for this operation. For each of these batteries, the occurrence of appearance defects due to deformation such as breakage of the opening of the exterior label 8 due to contact when the insulating ring 14 was inserted was examined. Of 100
And 390 out of 100 batteries with an angle θ of 30 ° had defective appearance, respectively, but all batteries with an angle θ of 20 ° or more did not have any defective appearance in 100 cells. Was.

Further, as shown in FIG. 3, a drop test was performed using an angle adjusting plate 18 capable of arbitrarily setting an angle α with respect to a horizontal installation floor surface 17. That is, the angle α of the angle adjusting plate 18 is set in a range of 0 to 90 °, specifically, 0.
°, 30 °, 45 °, 60 °, 90 ° in order,
Each time the angle is set, each of the above five types of batteries Ba is
The battery Ba is naturally dropped from the installation floor surface 17 onto the angle adjusting plate 18 from a fixed height H, for example, a height H of 1 m, while maintaining a posture in which its axis coincides with the vertical line. The presence or absence of the ring 14 was confirmed.

As a result, a battery Ba having an angle θ of 10 ° between a tangent line which is in contact with the outer peripheral end of the insulating ring 14 and the outer surface of the bent portion 1a of the battery case 1 and the axis of the battery Ba is 10 °.
Is dropped on the angle adjusting plate 18 in which the angle α is set to 45 ° and 60 °, and the battery Ba having the angle θ of 20 ° is placed in the angle adjusting plate 18 in which the angle α is set to 45 °. In the case where the insulating ring 14 was dropped, the insulating ring 14 was found to be dropped. However, in each battery Ba having the angle θ of 30 ° or more, regardless of the angle α,
No detachment of the insulating ring 14 was observed at all.

Therefore, from the results of this test, the battery of the above-described embodiment is characterized in that the outer diameter r of the insulating ring 14 is changed to a tangential line which makes contact with the outer peripheral end of the insulating ring 14 and the outer surface of the bent portion 1 a of the battery case 1. Angle between the battery and the axis of the battery is 3
The angle is set to 0 ° or more, so that the insulating ring 14
Does not break through the exterior label 8 and fall off, and since the angle θ is 20 ° or more, deformation such as breakage of the opening of the exterior label 8 due to the insertion operation of the insulating ring 14 during manufacturing. It was found that there was no appearance defect caused by the above.

Further, in the battery of this embodiment, as shown in FIG. 1, the outer terminal surface 4b of the negative electrode terminal plate 4 is positioned outside the bent portion 8a attached to the outer surface of the insulating ring 14 of the outer label 8. The terminal surface 4b is slightly recessed from the surface, and the depth d of the bent portion 8a of the terminal surface 4b with respect to the outer surface is set to an extremely small value of about 1 mm.

In a device using a plurality of batteries connected in series, this battery is erroneously set in a battery storage box with an opposite polarity to an adjacent battery shown by a two-dot chain line in FIG. The bent portions 8a of the exterior label 8 on the respective negative electrode sides facing each other of both batteries are in contact with each other, and the respective terminal surfaces 4b of the respective negative electrode terminal plates 4 have a dent depth d.
Are not electrically connected because they cannot face each other with a gap twice as large as. Therefore, the battery connected in the opposite polarity is not charged by the adjacent battery, so that even if the battery is left in the reverse connection state for a long time, the sealing member 3 is not charged.
The explosion-proof mechanism including the thin portion 3c does not operate, and the electrolyte does not leak out of the battery case 1 from the gap between the insulating ring 14 and the negative electrode terminal plate 4.
The expected life of the battery can be secured.

[0029]

As described above, according to the cylindrical battery of the present invention, the outer diameter of the insulating ring is set smaller than the outer diameter of the battery case, and the outer diameter of the insulating ring and the outer surface of the battery case are common. Angle between the tangent to the battery and the axis of the battery,
Since the angle of the axis with respect to the vertical line falls within 30 ° or less and collides with a horizontal object, the impact force received by the insulating ring is The component in the axial direction of the battery, that is, in the thickness direction of the insulating ring is almost the same, and the component in the width direction of the battery, that is, the component in the radial direction of the insulating ring is small, while the angle of the axial center with respect to the vertical line is 30 °. When the battery case falls below 90 ° and collides with a horizontal object, the outer peripheral surface of the battery case collides with the object first, and a large impact force is not applied to the insulating ring. For this reason, the insulating ring has a structure in which a large impact force such as shifting in the width direction of the battery is not applied, even when the insulating ring is configured to be held only by adhesion and heat shrinkage by the external label without using an adhesive, There is no danger of breaking through the outer label and falling off the battery.

In addition, since the outer diameter of the insulating ring is set smaller than the outer diameter of the battery case, that is, the inner diameter of the outer label, at the time of manufacturing, the insulating ring is inserted into the opening of the outer label to bend the battery case. The mounting step of contacting the caulked portion can be performed easily and quickly, and the appearance of the opening of the outer label is not deformed by the inserted insulating ring, and the appearance defect does not occur.

[Brief description of the drawings]

FIG. 1 is a half longitudinal sectional view showing a cylindrical battery according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the cylindrical battery.

FIG. 3 is an explanatory view of a cylindrical battery test apparatus.

FIG. 4 is a half vertical sectional view of a sealing portion of a conventional cylindrical battery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery case 1a Bent crimping part 3 Sealing body 3b Folding part 4 Negative terminal plate 4b Terminal surface 8 Exterior label 8a Bending part 14 Insulation ring r Outside diameter of insulation ring R Inner diameter of exterior case θ angle

Continued on the front page (72) Inventor Takeshi Okubo 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. ) 5H011 AA01 AA13 DD15 FF03 GG02 HH02 JJ11 KK03

Claims (2)

[Claims] 1. A bent crimped portion obtained by bending an opening of a cylindrical battery case inward and crimping it is pressed against a negative electrode terminal plate via a folded portion of an insulating sealing body. The opening is hermetically sealed, and an insulating ring abutting on the outer surface of the bent and swaged portion is held by covering the inwardly bent portion of the open end of the outer label covering the outer peripheral surface of the battery case. In the cylindrical battery, the outer diameter of the insulating ring is set to be smaller than the outer diameter of the battery case, and a tangent line commonly in contact with an outer peripheral end of the insulating ring and an outer surface of the battery case, and an axis of the battery. A cylindrical battery whose angle is set to be 30 ° or more. 2. The cylindrical battery according to claim 1, wherein the outer terminal surface of the negative electrode terminal plate is recessed inward from the outer surface of the bent portion of the outer label.