KR20050022269A - Sealing plate and gastight battery - Google Patents

Abstract

PURPOSE: Provided are a sealing plate to prevent the generation of deviation of internal pressure and a sealed battery using the sealing plate. CONSTITUTION: The sealing plate(3) comprises a plate part(4) which seals the open part(2a) of a container(2) to form the outer angle of a sealed battery(1) together with the container; a valve(5) which is formed at the some part of the plate part, is thinner than the plate of the plate part, and has a bent part(5b) which is bent to the thickness direction of the plate; and a groove(6) which is continuously extended at the position having at least one bent part from the outer circumference part(5a) of the valve. Preferably the sealing plate comprises further at least one auxiliary groove(9) which extends from the short part of the groove to the outer circumference part(5a) of the valve to the direction crossing the groove.

Description

SEALING PLATE AND GASTIGHT BATTERY}

The present invention relates to a sealed plate and a sealed battery having a valve for regulating the pressure inside the container.

There is a sealed battery in which a sealing plate is provided with a valve (pressure regulating valve) function for releasing internal gas when the pressure inside the container becomes excessive. This sealed battery is disclosed in, for example, Japanese Patent Laid-Open No. 2002-367583. The valve is composed of a recess, a bulge and a groove. The recess is provided in a part of the sealing plate to reduce the plate thickness. Two bulging parts are arranged symmetrically from the center on the bottom face of the recess. The groove extends from the center of the bottom face of the recess to the vicinity of the boundary (near the edge) and further surrounds two bulging portions, respectively.

When the internal pressure of the sealed battery rises and exceeds the set breaking pressure, the valve starts to break sequentially from the groove located at the center of the recess. The valve is opened by the grooves breaking toward the boundary near each other. That is, the valve works.

However, the plate | board thickness of a sealing plate changes rapidly in the boundary part of a recessed part and another part, and stress is easy to concentrate. The groove has a smaller plate thickness than the bottom portion, and is provided at the edge portion of the bottom surface that is near the boundary portion. Therefore, when the deformation is applied to the sealing plate due to an impact such as dropping the sealed battery, stress is concentrated in the groove. As a result, the bottom surface of the recess ruptures along the groove even at an internal pressure lower than the set operating pressure. That is, a valve may operate by the impact of a fall.

Therefore, the strength of the valve must be set higher than the set operating pressure. In addition, since the allowable amount of the stress due to the internal pressure applied to the groove is changed by the stress due to the deformation applied from the outside, it causes a deviation in the operating pressure of the valve.

Accordingly, an object of the present invention is to provide a sealing plate and a sealed battery having a valve that operates with high accuracy with respect to a set operating pressure.

The sealing plate which concerns on this invention is equipped with a plate part, a valve, and a groove. The plate portion seals the opening of the container to form the outer shell of the sealed battery together with the container. The valve has a curved portion formed in a portion of the plate portion that is thinner than the plate thickness of the plate portion and is bent in the plate thickness direction. The groove extends continuously at a position between at least one curved portion from the outer peripheral edge of the valve.

In addition, in order to facilitate opening the valve, at least one auxiliary groove is formed extending from the end of the groove toward the outer periphery of the valve in the direction crossing the groove. Alternatively, at least two auxiliary grooves branching from the ends of the grooves are provided. In this case, the auxiliary groove extends from the end of the groove toward the outer circumference and stops in the middle of the curved portion, or extends from the end of the groove to the outer circumference across the curved portion.

In order to prevent contact with the valve and breakage when handling the sealing plate, the valve is stored inside the plate thickness of the plate portion.

In the case of a sealed battery in combination with a container, in order to prevent stress from concentrating on the inner surface side of the boundary portion of the valve and the plate portion due to internal pressure, the outer peripheral portion of the valve is separated from the inner surface of the plate portion facing the container. It is formed continuously in a plane. Alternatively, the outer periphery of the valve is formed by smoothly continuing the middle of the plate thickness of the plate portion.

The sealed battery according to the present invention is premised on having a container having an opening and a sealing plate which seals the opening to form a part of the outer shell together with the container. The sealing plate includes a plate portion, a valve, and a groove. The plate portion is joined at the container and the outer circumference. The valve has a curved portion formed in a portion of the plate portion that is thinner than the plate thickness of the plate portion and is bent in the plate thickness direction. The groove extends continuously from the outer periphery of the valve to a position sandwiching at least one curved portion.

According to the sealing plate according to the present invention and the sealed battery according to the present invention, the stress applied from the outside due to drop impact or deformation can be alleviated by the deformation of the curved portion of the valve, and the concentration of stress in the groove can be suppressed. In other words, the internal pressure at which the valve actually operates with respect to the set operating pressure is less likely to be affected by stresses applied from the outside, such as impact or deformation of drops. Therefore, a deviation can be prevented in the internal pressure at which the valve actually operates.

In addition, the stress applied to the groove is mainly caused by the internal pressure. For this reason, it is not necessary to increase the strength of the groove by adding stress applied from the outside such as deformation. Therefore, the valve has a small difference from the internal pressure actually operated with respect to the set working pressure, and the deviation of the working pressure becomes small.

A first embodiment according to the present invention will be described with reference to FIGS. 1 to 6. The sealed battery 1 provides a container 2 and a sealing plate 3 that form an outer shell as shown in FIG. 1. The sealing plate 3 is provided with the plate part 4, the valve 5, and the groove | channel 6 as shown in FIG.

The plate part 4 is provided in the outer peripheral part 4a with the level | step difference which fits with the opening part 2a of the container 2. As shown in FIG. The bevel in which the outer periphery 4a and the edge of the opening 2a butt together is seal welded W by laser welding or the like. In addition, as shown in FIG. 1, a gasket 7 is inserted into the center portion of the plate portion 4 so that the terminal 8 is mounted. The terminal 8 penetrates the plate part 4 in the plate thickness direction, and is connected with the electrode accommodated in the inside of the container 2.

As shown in FIG. 2, the valve 5 is formed in a portion of the plate portion 4 so as to be thinner than the plate thickness of the plate portion 4. The valve 5 is molded by pressing a part of the plate portion 4 by press molding to reduce the plate thickness. The outer peripheral part 5a of the valve 5 is continuous in one surface with the inner side surface 4b of the plate part 4 which faced the inside of the container 2. As shown in FIG. Moreover, the valve 5 has the curved part 5b bent in the plate | board thickness direction. In this case, the curved portion 5b is bent toward the outside of the container 2 from the outer circumferential edge 5a toward the center, and then bent toward the inside of the container 2 over the central portion of the valve 5. . The valve 5 is housed inward of the plate thickness of the plate portion 4.

The groove 6 extends continuously in the position which sandwiched the curved part 5b from the outer peripheral part 5a of the valve 5, as shown to FIG. The groove 6 is formed thinner than the plate thickness of the valve 5, as shown in FIG. 2 and FIG. Further, an auxiliary groove 9 is provided extending from the end 6a of the groove 6 toward the outer circumferential portion 5a of the valve 5 in the direction crossing the groove 6.

In the present embodiment, as shown in FIGS. 3 and 4, the valve 5 is provided in a rectangular shape, and the groove 6 is disposed along the longitudinal direction at the center of the valve 5. The auxiliary grooves 9 branch in two from the end portions 6a of the grooves 6 and extend across the curved portions 5b to the outer peripheral edge portions 5a that become the square near sides of the valve 5 installed in a rectangle. It is.

In addition, the groove 6 and the auxiliary groove 9 are formed in one surface with the inner surface 4b of the plate portion 4. Portions other than the groove 6 and the auxiliary groove 9 are expanded in the plate thickness direction of the plate portion 4 toward the outside of the container 2.

In the sealed battery 1 configured as described above, when the internal pressure of the container 2 is applied, the valve 5 is pressurized toward the outside of the container 2. Tensile stress acts on the groove 6 and the auxiliary groove 9. When the internal pressure is higher than the set operating pressure, cracks occur along the groove 6 and the auxiliary groove 9 starting from the end 6a of the groove 6. As shown in FIG. 6, the valve 5 is cracked open. In other words, the valve 5 operates as a pressure regulating valve. Since the outer periphery 5a is continuous with the plate 4, the valve 5 does not fall off from the plate 4 even after crack opening (operation).

Moreover, since the curved part 5b is provided in the valve 5 and the groove | channel 6 is provided in the position which sandwiched the curved part 5b from the outer peripheral part 5a of the valve 5, the sealed battery ( Even if the sealing plate 3 is impacted or deformed from the outside due to 1) falling down or the like, the curved portion 5b is deformed and stress concentration in the groove 6 is prevented. In other words, the internal pressure at which the valve 5 operates is less likely to be affected by the stress due to impact or deformation applied to the sealing plate 3 from the outside.

Therefore, since the stress due to the internal pressure is mainly the stress applied to the groove 6, the deviation of the internal pressure actually operating with respect to the set operating pressure becomes small. That is, the valve 5 operates with high precision with respect to the set operating pressure. In addition, since it is not necessary to increase the strength of the groove 6 by applying the impact or deformation applied to the sealing plate 3 from the outside, the operating pressure of the valve 5 can be set low.

A second embodiment according to the present invention will be described with reference to FIG. In addition, about the structure which has the same function as 1st Example, the same code | symbol is attached | subjected and the description is abbreviate | omitted. As shown in FIG. 7, the valve 5 provided in a part of the plate part 4 of the sealing plate 3 has the outer periphery part 5a smoothly with the middle 4c of the plate thickness of the plate part 4. As shown in FIG. It is continuous. Moreover, the groove 6 and the auxiliary groove 9 are provided from the side facing the inside of the container 2 in the position which sandwiched the curved part 5b from the outer peripheral part 5a of the valve 5. In addition, the top view which looked at the groove | channel 6 and the auxiliary groove | channel 9 from the outer side of a container is substantially the same state as FIG.

As for the sealing plate 3 of the sealed type battery 1 formed as mentioned above, the outer peripheral part 5a of the valve 5 is smoothly continued with the middle 4c of the plate | board thickness of the plate part 4. As shown in FIG. Therefore, it is possible to prevent the concentration of tensile stress due to internal pressure at the boundary between the outer periphery 5a and the plate 4. In addition, the groove 6 and the auxiliary groove 9 are provided on the side facing the inside of the container 2. Therefore, when the valve 5 is pushed outward by applying the internal pressure to the sealed battery 1, the compressive stress acts on the groove 6 and the auxiliary groove 9.

Thus, even when the valve 5 receives the internal pressure which does not satisfy an operating pressure repeatedly, fatigue does not accumulate. Therefore, when this sealing plate 3 is applied to a secondary battery in which charging and discharging are repeated, the following effects can be obtained. Since the valve 5 has the curved part 5b, it is not influenced by the deformation applied to the sealing plate 3 from the outside. Therefore, the valve 5 operates with high precision with respect to the set operating pressure. In addition, even when the internal pressure less than the operating pressure is repeatedly applied by repeated charging and discharging, fatigue is hardly accumulated in the groove 6 of the valve 5. As a result, the sealed battery 1 excellent in durability can be provided.

A third embodiment according to the present invention will be described with reference to FIG. In addition, about the structure which has the function similar to 1st and 2nd Example, the same code | symbol is attached | subjected and the description is abbreviate | omitted. As shown in FIG. 8, the outer peripheral part 5a of the valve 5 is provided continuously in one surface with the inner side surface 4b of the plate part 4. As shown in FIG. The shape of the valve 5 seen from the outside of the container 2 is elliptical. The valve 5 has the curved part 5b which curves toward the outer side of the container 2, and is formed so that the whole may be raised to a dome shape. The groove 6 is provided in the elliptical center part at the position which sandwiched the curved part 5b from the outer peripheral part 5a of the valve 5 in this embodiment. In addition, like the first and second embodiments, the valve 5 of the sealing plate 3 does not have an auxiliary groove.

In the sealed battery 1 thus formed, even if an impact or deformation is applied to the sealing plate 3 from the outside, the stress caused by the deformation is alleviated by the curved portion 5b. Therefore, concentration of stress in the groove 6 can be prevented. The stress acting on the valve 5 is not affected by the impact or deformation applied to the sealing plate 3 from the outside, and the stress due to the internal pressure is the main one. As a result, the variation in the internal pressure at which the valve 5 actually operates with respect to the set operating pressure becomes small. That is, the valve 5 operates precisely with respect to the set operating pressure. In addition, it is not necessary to increase the strength of the groove 6 in consideration of the influence of the impact or deformation applied to the sealing plate 3 from the outside. Thus, the valve 5 can be set to operate at a low internal pressure.

Moreover, the groove | channel 6 provided in the sealing plate 3 and the valve | bulb 5 of the sealed battery 1 of this invention has the curved part 5b between the outer periphery 5a of the valve 5 at least. It may be extended continuously to the position. In addition, the auxiliary groove 9 may be installed as follows. The auxiliary groove 9 has at least one extending from the end 6a of the groove 6 toward the outer periphery 5a of the valve 5 in the direction intersecting the groove 6, or in the first embodiment As shown in the drawing, at least two branches from the end 6a of the groove 6 are provided. In this case, the auxiliary groove 9 may extend from the end 6a of the groove 6 toward the outer periphery 5a of the valve 5 to stop in the middle of the curved portion 5b, or the groove 6 It may be formed so as to extend from the end 6a of the to the outer periphery 5a across the curved part 5b.

Therefore, what sorted about the various arrangement | positioning of the groove | channel 6 and the auxiliary groove | channel 9 is shown typically to FIG. 9A-9Z. In each figure, the outermost line shows the boundary of the plate part 4 and the valve 5. In addition, the range shown by hatching is the curved part 5b.

The valve 5 shown in FIGS. 9A to 9J is elliptical, and the valve 5 shown in FIGS. 9K to 9T and 9Z is rectangular. The valve 5 shown in FIG. 9U and FIG. 9V is circular, and the valve 5 shown in FIGS. 9W-9Y is square.

In the valve 5 shown in FIGS. 9A to 9E, 9K to 9O, and 9U, it is common that the auxiliary groove 9 crosses the curved portion 5b. In the valve 5 shown in FIGS. 9F to 9J, 9P to 9T, and 9Y, it is common that the end of the auxiliary groove 9 is stopped in the middle of the curved portion 5b. In the valve 5 shown in FIG. 9V, two auxiliary grooves 9 extend from one end 6a of one groove 6 and do not intersect the curved portion 5b. In addition, the valve 5 shown to FIG. 9W, FIG. 9X, and FIG. 9Z does not have the auxiliary groove 9. As shown in FIG.

9A, 9C to 9F, 9H to 9K, 9M to 9P, and 9R to 9T, the valve 5 has an auxiliary groove 9 from both ends 6a of the groove 6; Each extends two. 9b, 9g, 9l, 9q, 9u, and 9y, one auxiliary groove 9 extends from the both ends 6a of the groove 6, respectively.

9A, 9B, 9E, 9F, 9G, 9J, 9K, 9L, 9O, 9P, 9Q, 9T, 9U, 9V, and 9Y, and the valve 5 shown in Figs. ), The auxiliary groove 9 is formed in a straight shape, and the valve 5 shown in FIGS. 9C, 9D, 9H, 9I, 9M, 9N, 9R, and 9S is an auxiliary groove 9. It is formed in the shape of an arc. 9E, 9J, 9O, and 9T, the valve 5 is arrange | positioned in the direction orthogonal to the auxiliary groove 9 with respect to the groove | channel 6. As shown in FIG.

According to the sealing plate according to the present invention and the sealed battery according to the present invention, the stress applied from the outside due to drop impact or deformation can be alleviated by the deformation of the curved portion of the valve, and the concentration of stress in the groove can be suppressed. In other words, the internal pressure at which the valve actually operates with respect to the set operating pressure is less likely to be affected by stresses applied from the outside, such as impact or deformation of drops. Therefore, a deviation can be prevented in the internal pressure at which the valve actually operates.

In addition, the stress applied to the groove is mainly caused by the internal pressure. For this reason, it is not necessary to increase the strength of the groove by adding stress applied from the outside such as deformation. Therefore, the valve has a small difference from the internal pressure actually operated with respect to the set working pressure, and the deviation of the working pressure becomes small.

1 is a perspective view showing a sealed battery of a first embodiment according to the present invention;

2 is a cross-sectional view taken along the line F2-F2 of the valve installed in the sealing plate shown in FIG. 1;

3 is a plan view of the valve shown in FIG. 1 seen from the outside of the sealed battery;

4 is a plan view of the valve shown in FIG. 1 as viewed from the inside of the sealed battery;

5 is a cross-sectional view taken along F5-F5 of the valve installed in the sealing plate shown in FIG. 3;

FIG. 6 is a perspective view in partial cross section in a state in which the valve shown in FIG. 1 is opened by an operating pressure; FIG.

7 is a cross-sectional view showing a valve provided in a sealing plate for the sealed battery of the second embodiment according to the present invention;

Fig. 8 is a perspective view showing, in partial cross section, a valve provided on a sealing plate of the sealed battery of the third embodiment according to the present invention;

9A to 9Z schematically show examples of arrangement of grooves and auxiliary grooves of a valve provided in the sealing plate of the present invention.

Explanation of symbols for the main parts of the drawings

1: sealed battery 2: container

2a: opening 3: sealing plate

4: plate portion 4a: outer peripheral portion

4b: inner side 5: valve

5a: outer periphery 5b: bend

6: groove 6a: end

9: auxiliary home

Claims (9)

In the sealing plate 3, A plate portion 4 which seals the opening 2a of the container 2 to form the outer shell of the sealed battery 1 together with the container 2, A valve 5 having a curved portion 5b formed in a portion of the plate portion 4 thinner than the plate thickness of the plate portion 4 and bent in the plate thickness direction; And a groove (6) extending continuously from the outer circumferential portion (5a) of the valve (5) to at least one of the curved portions (5b). Sealing plate. The method of claim 1, At least one auxiliary groove (9) extending from the end (6a) of the groove (6) toward the outer periphery (5a) of the valve (5) in a direction intersecting with the groove (6). doing Sealing plate. The method of claim 1, Characterized by having at least two auxiliary grooves 9 branching from the end 6a of the groove 6. Sealing plate. The method of claim 2 or 3, The auxiliary groove 9 is characterized in that it extends from the end 6a of the groove 6 toward the outer periphery 5a and stops in the middle of the curved portion 5b. Sealing plate. The method of claim 2 or 3, The auxiliary groove 9 is characterized in that it extends from the end 6a of the groove 6 to the outer circumferential portion 5a across the curved portion 5b. Sealing plate. The method of claim 1, The valve 5 is characterized in that it is housed inward than the plate thickness of the plate portion 4 Sealing plate. The method of claim 1, The outer periphery 5a of the valve 5 is characterized in that it is continuously formed in one surface from the inner surface 4b of the plate portion 4 facing the inside of the container 2. Sealing plate. The method of claim 1, The outer periphery 5a of the valve 5 is characterized in that it is formed continuously and smoothly in the middle of the plate thickness of the plate 4 Sealing plate. In the sealed battery 1 which forms an outer shell by the container 2 which has the opening part 2a, and the sealing plate 3 which seals the said opening part 2a, The sealing plate 3, A plate portion 4 joined to the container 2 and an outer circumferential portion 4a, A valve 5 having a curved portion 5b formed in a portion of the plate portion 4 thinner than the plate thickness of the plate portion 4 and bent in the plate thickness direction; And a groove (6) extending continuously from the outer circumferential portion (5a) of the valve (5) to at least one of the curved portions (5b). Hermetic battery.