JP2006210275A - Cylindrical alkaline battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylindrical alkaline battery having a self-restoration type explosion-proof structure which can be repeatedly used, capable of surely preventing leakage of alkaline electrolyte when the explosion-proof structure is operated. <P>SOLUTION: A bottom part of a positive electrode can 11 having a vent hole 14 is covered by a positive electrode terminal plate 12. A reciprocal pressure operation valve is formed by closing the vent hole 14 by a rubber valve 13 arranged between the bottom part of the positive electrode can 11 and the positive electrode terminal plate 12 in compressed state. A gas permeable and non-liquid permeable film 16 is arranged on an exhaust passage extending from inside of the positive electrode can to the outside of the battery 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cylindrical alkaline battery having an explosion-proof function, and particularly to a battery having a self-recovery type explosion-proof mechanism that can be used repeatedly.

  As shown in FIG. 4A, the alkaline battery (dry battery) accommodates the power generation element 20 in a bottomed cylindrical metal battery can 11 and the opening of the positive electrode can 11 through a gasket 26. The negative electrode terminal plate 25 is closed and sealed.

  The power generation element 20 includes an annular positive electrode mixture 21 inserted in the positive electrode can 11 in a press-fitted state, a cylindrical separator 22 impregnated with an alkaline electrolyte, and a gel-like zinc negative electrode filled inside the separator 22. It is comprised by the agent 23. A rod-shaped negative electrode current collector 24 is inserted into the negative electrode mixture 23. The negative electrode current collector 24 is connected to the inner surface of the negative electrode terminal plate 25 by spot welding or the like.

  The positive electrode can 11 also serves as a positive electrode current collector by press-fitting an annular solid positive electrode mixture 21 on the inner surface thereof. Here, in the illustrated battery 10 ′, the positive electrode terminal is formed by the positive electrode terminal plate 12 that covers the outer bottom surface of the positive electrode can 11 as shown in a partially enlarged view in FIG. An exhaust hole 14 is formed at the bottom of the positive electrode can 11. The exhaust hole 14 is closed between the bottom of the positive electrode can 11 and the positive electrode terminal plate 12 by a rubber valve 13 provided in a compressed state.

  The space between the positive electrode terminal plate 12 and the rubber valve 13 is opened to atmospheric pressure by a vent hole 15 provided in the positive electrode terminal plate 12. When the internal pressure of the positive electrode can 11 exceeds a certain limit due to the generation of gas in the battery 10 ', the internal pressure causes the rubber valve 13 closing the exhaust hole 14 to be compressed and retreated, thereby opening the exhaust hole 14. An exhaust path (practical arrow) through which the generated gas inside the battery escapes is formed. That is, an explosion-proof function that prevents the battery from rupturing or breaking is activated.

  The above-described explosion-proof mechanism is not an irreversible explosion-proof operation that is activated when the gasket 26 is broken by the battery internal pressure, but after the explosion-proof operation, if the battery internal pressure returns to the normal range, the rubber valve 13 is elastically restored and exhausted. By closing the hole 14 again, it is possible to automatically return to the state before the operation. That is, it is a reversible explosion-proof mechanism that can be used repeatedly. This self-recovery type explosion-proof mechanism is disclosed in Patent Document 1, for example.

The cylindrical alkaline battery having the above-described self-recovery explosion-proof function can continue to be used as long as the battery can generate power even after the gas is released. Gas generation often occurs due to temporary causes such as misuse, and in this case, even if gas is generated, the function of the battery is continued if it can be appropriately released.
JP 2001-76701 A

However, the present inventors have revealed that the conventional cylindrical alkaline battery described above has the following problems.
That is, when the explosion-proof mechanism is activated, an exhaust path is formed by compression / retraction of the rubber valve 13 due to the battery internal pressure. At this time, not only the gas in the battery but also the alkali in the battery accompanying the gas. It has been found that the electrolyte is also discharged out of the battery, resulting in so-called leakage. The leakage in this case is not as large as when the battery seal is broken, but the alkaline electrolyte, which is a strong alkaline solution, stains the equipment and surroundings even with a small amount of leakage, causing corrosion, etc. It causes various obstacles.

  The present invention has been made in view of the above problems, and its purpose is to provide a self-returning explosion-proof mechanism that can be used repeatedly, and to prevent leakage of alkaline electrolyte when the explosion-proof mechanism is activated. It is an object of the present invention to provide a cylindrical alkaline battery that can be surely prevented.

  Other objects and configurations of the present invention will become apparent from the description of the present specification and the accompanying drawings.

Means provided by the present invention are as follows.
(1) It has a bottomed cylindrical positive electrode can that houses a power generation element, a negative electrode terminal plate that seals the opening of the positive electrode can through a gasket, and a positive electrode terminal plate that covers the outer bottom surface of the positive electrode can An exhaust hole is formed in the bottom of the positive electrode can, and a reversible pressure-actuated valve is formed by closing the exhaust hole with a rubber valve provided in a compressed state between the bottom of the positive electrode can and the positive electrode terminal plate. A cylindrical alkaline battery characterized in that a non-liquid permeable film having gas permeability is interposed in an exhaust path from the inside of the positive electrode can to the outside of the battery.

In the above means (1), it is particularly effective to provide the following means together.
(2) A cylindrical alkaline battery characterized in that, in the means (1), a gas-permeable non-liquid permeable film is interposed in an exhaust path from the inside of the positive electrode can to the rubber valve. .

(3) The cylindrical alkaline battery according to the means (1) or (2), wherein the film closes the exhaust hole in a state of being interposed between an outer bottom surface of the positive electrode can and the rubber valve. .

(4) In any one of the above means (1) to (3), the film is bonded to the positive electrode can bottom at an annular portion surrounding the exhaust hole of the positive electrode can bottom. battery.

(5) The cylindrical alkaline battery according to the above means (1) or (2), wherein the film closes the exhaust hole while being attached to the inner bottom surface of the positive electrode can.

  A self-returning explosion-proof mechanism that can be used repeatedly and a cylindrical alkaline battery that reliably prevents leakage of alkaline electrolyte when the explosion-proof mechanism is activated can be provided.

  Operations / effects other than those described above will be apparent from the description of the present specification and the accompanying drawings.

  FIG. 1 shows an embodiment of a cylindrical alkaline battery 10 to which the technology of the present invention is applied. First, as shown to (a) of the figure, the alkaline battery (dry battery) 10 which concerns on this invention accommodates the electric power generation element 20 in the bottomed cylindrical metal battery can 11, and opening of the positive electrode can 11 is carried out. The portion is configured to be closed and sealed with the negative electrode terminal plate 25 via the gasket 26.

  The power generation element 20 includes an annular positive electrode mixture 21 inserted in the positive electrode can 11 in a press-fitted state, a cylindrical separator 22 impregnated with an alkaline electrolyte, and a gel-like zinc negative electrode filled inside the separator 22. It is comprised by the agent 23. A rod-shaped negative electrode current collector 24 is inserted into the negative electrode mixture 23. The negative electrode current collector 24 is connected to the inner surface of the negative electrode terminal plate 25 by spot welding or the like.

  The positive electrode can 11 also serves as a positive electrode current collector by press-fitting an annular solid positive electrode mixture 21 on the inner surface thereof. Further, as shown in a partially enlarged view in (b) of the figure, the positive electrode terminal is formed by a positive electrode terminal plate 12 that covers the outer bottom surface of the positive electrode can 11. An exhaust hole 14 is formed at the bottom of the positive electrode can 11. The exhaust hole 14 is closed between the bottom of the positive electrode can 11 and the positive electrode terminal plate 12 by a rubber valve 13 provided in a compressed state.

  The rubber valve 13 is configured using rubber or a rubber-like elastic material, and has a substantially disk shape or a column shape.

  The space between the positive electrode terminal plate 12 and the rubber valve 13 is opened to atmospheric pressure by a vent hole 15 provided in the positive electrode terminal plate 12. When the internal pressure of the positive electrode can 11 exceeds a certain limit due to gas generation in the battery 10, the internal pressure compresses the rubber valve 13 that has closed the exhaust hole 14 and retreats, and the exhaust hole 14 opens to open the inside of the battery. An exhaust path (dotted arrow) through which the generated gas escapes to the outside is formed. That is, an explosion-proof function that prevents the battery from rupturing or breaking is activated.

  Further, in the battery 10 of this embodiment, in addition to the above configuration, a gas-permeable non-liquid permeable film 16 is interposed in the exhaust path from the positive electrode can 11 to the rubber valve 13. The film 16 is made of a film material that allows gas to pass but is non-permeable (waterproof) to a liquid such as an alkaline electrolyte, and the outer bottom surface of the positive electrode can 11 and a rubber valve. The exhaust hole 14 is blocked while being interposed between the two.

  As the film 16, for example, a visual field selective film described in Patent Document 2 can be used. This visual field selective film is provided with a striped craze region substantially parallel to the molecular orientation direction of the polymer resin film, and this craze is air-permeable but impervious to liquid permeation. Indicates. In this embodiment, a monotran film (trade name) provided on the market was used as the film having the craze.

  Even if the film 16 is present, the high-pressure gas generated in the battery 10 permeates the film 16 and presses the rubber valve 13 due to the gas permeability of the film 16. As a result, the rubber valve 13 is compressed and retracted, and the exhaust hole 14 is opened to form an exhaust path (dotted line arrow) through which the generated gas inside the battery 10 is discharged to the outside. That is, the explosion-proof function for preventing the battery from rupturing or breaking can operate normally. At this time, the alkaline electrolyte in the battery is blocked by the film 16 due to the non-liquid permeability of the film 16 and is prevented from leaking to the outside.

  As a result, the explosion-proof mechanism can be automatically restored and used repeatedly when the battery internal pressure returns to the normal range, and can reliably prevent leakage of alkaline electrolyte when the explosion-proof mechanism is activated. it can.

  In the above configuration, in order for the film 16 to more reliably block the movement of the alkaline electrolyte, the film 16 is an exhaust of the bottom of the positive electrode can 11 as shown in a plan view of the film 16 in FIG. A structure in which the annular portion surrounding the hole is bonded to the bottom of the positive electrode can 11 is particularly effective. Reference numeral 161 in (c) of FIG. This adhesion can be performed by use of an adhesive or heat fusion. In the embodiment, bonding was performed using Mighty Ace G150 manufactured by Yasuhara Chemical Co., Ltd.

  Here, the alkaline battery (LR6 dry battery) of the present invention in which the film 16 is interposed and the alkaline battery (LR6 dry battery) having a conventional structure in which the film 16 is not interposed are experimentally manufactured. As shown in FIG. 2, it was confirmed that the leakage rate of the product of the present invention with respect to the number of storage days was remarkably improved as compared with the conventional product.

  As shown in FIG. 2, the conventional product gradually began to leak from the 15th day after storage, but the product of the present invention was able to suppress the leak rate to 0%. This indicates that the film 16 was able to reliably block leakage of the alkaline electrolyte.

  FIG. 3 shows a main part of a further preferred embodiment of the present invention. Focusing on the difference from the above embodiment, in the embodiment shown in the figure, the exhaust hole 14 is closed while the film 16 is mounted on the inner bottom surface of the positive electrode can 11. In this case, when the battery internal pressure becomes high, the film 16 is strongly pressed against the inner bottom surface side of the positive electrode can 11 by the internal pressure, thereby further increasing the degree of adhesion with the inner bottom surface.

  As a result, the film 16 can reliably prevent the alkaline electrolyte from moving to the outside even if the film 16 is not simply adhered to the inner bottom surface of the positive electrode can 11 using an adhesive or the like. A close contact state that can be obtained can be obtained.

  In this case, the film 16 may be bonded for the purpose of accurately positioning the film 16 on the inner bottom surface of the positive electrode can 11 in the battery manufacturing process, for example. If the positioning can be performed without any particular trouble without using an adhesive, the bonding can be made unnecessary.

As described above, the present invention has been described based on the representative embodiments, but the present invention can have various modes other than those described above. For example, the film 16 may be attached to the inner surface of the positive electrode terminal plate 12 so as to close the vent hole 15 of the positive electrode terminal plate 12. Moreover, although the rubber valve 13 can be comprised using natural or synthetic rubber, elastic materials other than rubber | gum can also be used.
Japanese Patent No. 3156058

  A self-returning explosion-proof mechanism that can be used repeatedly and a cylindrical alkaline battery that reliably prevents leakage of alkaline electrolyte when the explosion-proof mechanism is activated can be provided.

It is sectional drawing of the cylindrical alkaline battery by one Example of this invention, and the enlarged view of the principal part. It is a graph which shows the 90 degreeC storage test result of the cylindrical alkaline battery by this invention. It is a principal part expanded sectional view which shows another embodiment of this invention. It is sectional drawing of the conventional cylindrical alkaline battery, and the enlarged view of the principal part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cylindrical alkaline battery 11 Positive electrode can 12 Positive electrode terminal board 13 Rubber valve 14 Exhaust hole 15 Ventilation hole 16 Film 161 Adhesion part 20 Electric power generation element 21 Positive electrode mixture 22 Separator 23 Negative electrode mixture 24 Negative electrode current collector 25 Negative electrode terminal board 26 Gasket

Claims (5)

  A positive electrode can having a bottomed cylindrical shape that houses a power generation element; a negative electrode terminal plate that seals an opening of the positive electrode can through a gasket; and a positive electrode terminal plate that covers an outer bottom surface of the positive electrode can. An exhaust hole is formed in the bottom of the can, and the exhaust hole is closed with a rubber valve provided in a compressed state between the bottom of the positive electrode can and the positive terminal plate, thereby forming a cylindrical alkali in which a reversible pressure-actuated valve is formed. A cylindrical alkaline battery characterized in that a non-liquid permeable film having gas permeability is interposed in an exhaust path from the inside of the positive electrode can to the outside of the battery.   2. The cylindrical alkaline battery according to claim 1, wherein a non-liquid permeable film having gas permeability is interposed in an exhaust path from the inside of the positive electrode can to the rubber valve.   3. The cylindrical alkaline battery according to claim 1, wherein the film closes the exhaust hole in a state of being interposed between the outer bottom surface of the positive electrode can and the rubber valve.   4. The cylindrical alkaline battery according to claim 1, wherein the film is bonded to the bottom portion of the positive electrode can at an annular portion surrounding the exhaust hole of the bottom portion of the positive electrode can. 3. The cylindrical alkaline battery according to claim 1, wherein the film closes the exhaust hole in a state where the film is attached to the inner bottom surface of the positive electrode can.

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