JP2008251213A - Sealed battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed battery capable of preventing certainly liquid leakage. <P>SOLUTION: In the sealed battery, a pillar-shape insertion part of the electrode external terminal is inserted and connected to a through hole and fixed to a sealing plate 3 through an insulating gasket 2. A first annular projection part 1c of non-perfect circle shape which surrounds the pillar-shape insertion part is formed at the face in contact with the insulating gasket at the flange part of the pillar-shape insertion part, and a second annular projection part 3b of non-perfect circle shape which surrounds the through hole is formed at the face opposed to the flange part at the sealing plate. When seen through the sealed battery from perpendicular direction to the sealed part, the first annular projection part 1c and the second annular projection part 3b are not overlapped. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealed battery, and more particularly to a technique for suppressing the occurrence of liquid leakage in a sealed battery.

  In recent years, non-aqueous electrolyte secondary batteries have come to be used as drive power sources not only for small devices such as mobile phones, notebook computers, and digital cameras, but also for electric vehicles and hybrid vehicles.

  In a battery used for such an application, since a high output is required, a plurality of batteries are connected in series as shown in FIG. 12, but the nonaqueous solvent of the nonaqueous electrolyte secondary battery is a nonaqueous solvent. Since flammable materials are used, high reliability against liquid leakage is required. Moreover, it is requested | required that it is excellent in impact resistance and vibration resistance from the characteristic of the use.

  Conventionally, since the electrode external terminal 1 of such a nonaqueous electrolyte secondary battery is easy to manufacture and process, a cross section perpendicular to the battery height direction has a perfect circle shape. However, the electrode external terminal rotates due to the position shift of the electrode external terminal of each battery or the impact received after series connection, etc., and a gap is generated between the electrode external terminal and the gasket for fixing the electrode, resulting in liquid leakage There was a problem that it was easy to do.

  The following patent documents 1-6 are mentioned as a technique regarding a nonaqueous electrolyte secondary battery.

Japanese Utility Model Publication No. 60-130561 Japanese Utility Model Publication No. 2-54162 JP 2003-132873 A JP2003-173767 Japanese Patent Laid-Open No. 10-340709 JP-A-9-153351

  Patent Document 1 discloses a columnar portion of an electrode external terminal having a columnar portion, a hook-shaped portion provided at one end of the columnar portion, and an annular convex portion provided so as to surround the columnar portion on the hook-shaped portion. This is a technique for inserting into a through hole provided in an electrode external terminal mounting portion of a resin body, deforming a columnar portion, and press-fitting an annular convex portion into the resin body. According to this technique, the sealing performance of the electrode external terminal portion is improved.

  However, this technique has a problem that when the electrode external terminal rotates due to vibration or impact, a gap is generated between the resin body and the electrode external terminal, resulting in liquid leakage.

  Patent Document 2 includes an outer can, a metal lid that is bonded and fixed to an opening edge of the outer can, and a terminal that is fixed to a through hole provided in the metal lid via an insulating packing, and the upper and lower surfaces of the metal lid. This is a technique in which a non-circular recess is formed on the periphery of the through-hole on at least one surface, and the extension portion of the insulating packing located in the recess cannot be rotated in the recess. According to this technique, it is said that a battery having excellent sealing properties between the insulating packing and the metal lid can be obtained.

  However, this technique has a problem that when the electrode external terminal rotates due to vibration or impact, a gap is generated between the resin body and the electrode external terminal, resulting in liquid leakage.

  Patent Document 3 is a technique related to an assembled battery in which a connection plate connected to positive and negative terminals of a secondary battery cell and a bypass switch are coupled by two or more coupling members. According to this technology, even if an open failure occurs in the positive and negative electrode terminal portions, it is possible to prevent the open failure of the entire assembled battery.

  However, in this technique, no consideration is given to liquid leakage when the electrode external terminal rotates due to vibration or impact.

  Patent Document 4 is a technique for forming a convex portion on the contact surface of the flange portion of the electrode lead-out pin with the insulating member surface. According to this technique, it is said that a battery excellent in hermeticity can be obtained.

  However, this technique has a problem that when the electrode external terminal rotates due to vibration or impact, a gap is generated between the resin body and the electrode external terminal, resulting in liquid leakage.

  In Patent Document 5, a prismatic battery in which a power generation element is housed in a prismatic battery can and sealed by an electrode header, a through hole of a conductive connection terminal is provided in a recess formed on the upper surface of a metal plate in the electrode header. An electrode header is formed by providing an insulating plate for insulating between the metal plate and the conductive connection terminal on the upper and lower surfaces of the metal plate and caulking the conductive connection terminal to firmly fix the conductive connection terminal and the metal plate. This is a technique in which the terminal is conductively connected to one electrode plate of the power generation element, and the electrode header is fixed and sealed to the battery can at a position where the upper surface of the electrode header is flush with the upper end of the battery can. According to this technique, it is said that a battery having high volumetric efficiency and excellent sealing properties can be obtained.

  However, this technique has a problem that when the electrode external terminal rotates due to vibration or impact, a gap is generated between the resin body and the electrode external terminal, resulting in liquid leakage.

  Patent Document 6 discloses an annular first protrusion that presses an insulating gasket against a flange or a metal washer of an other-polar terminal pin corresponding to at least one of the outer insulating gasket and the inner insulating gasket, and the first protrusion. And a second protrusion that presses the outer peripheral edge of the insulating gasket. According to this technique, it is said that a battery capable of suppressing the leakage of the electrolytic solution can be obtained.

  However, this technique has a problem that when the electrode external terminal rotates due to vibration or impact, a gap is generated between the resin body and the electrode external terminal, resulting in liquid leakage.

  The present invention has been made in view of the above, and it is an object of the present invention to provide a sealed battery that does not cause liquid leakage even when vibration or impact is applied.

  In order to solve the above problems, the present invention provides an electrode external terminal (1) having at least a flange portion (1b) and a columnar insertion portion (1a), and a through hole (2a) into which the columnar insertion portion (1a) is inserted. ) Provided with an insulating gasket (2), and a sealing plate (3) provided with a through hole (3a) into which the columnar insertion portion (1a) is inserted, and columnar insertion of the electrode external terminal A part (1a) communicates with the two through holes (2a, 3a), and is a sealed battery fixed to the sealing plate (3) via an insulating gasket (2). The part (1b) is formed with a non-round circular first protrusion (1c) surrounding the columnar insertion part (1a) on the surface in contact with the insulating gasket (2), and is formed on the sealing plate (3). Is a non-round circle surrounding the through hole (3a) on the surface facing the flange (1b) When the sealed battery is seen through from a direction perpendicular to the sealing plate (3), the annular first projection (1c) and the annular second projection (3b) are formed. The protrusion (3b) is not overlapped.

  According to this configuration, since the insulating gasket is compressed by the annular first projecting portion 1c and the annular second projecting portion 3b, the sealing performance between the electrode external terminal and the insulating gasket is enhanced. Moreover, since both the annular first protrusion 1c and the annular second protrusion 3b are non-circular, the electrode external terminal 1 cannot rotate along these annular protrusions. Further, when the sealed battery is seen through from a direction perpendicular to the sealing plate 3, the annular first protrusion 1c and the annular second protrusion 3b do not overlap with each other, and therefore the annular first protrusion 1c and the annular second protrusion 3b independently acts to suppress the rotation of the electrode external terminal. Therefore, a battery capable of preventing liquid leakage due to rotation of the electrode external terminal 1 is obtained.

  The said structure WHEREIN: The said cyclic | annular 1st projection part (1c) can be set as the structure currently formed in the ellipse shape, the track shape, or the rounded rectangle shape.

  The said structure WHEREIN: The said cyclic | annular 2nd projection part (3b) can be set as the structure currently formed in the ellipse shape, the track shape, or the rounded rectangle shape.

  According to these configurations, the annular first protrusion 1 c and the annular second protrusion 3 b can more effectively suppress the rotation of the electrode external terminal 1.

  The said structure WHEREIN: The said cyclic | annular 1st projection part (1c) is located in an outer peripheral side rather than the said cyclic | annular 2nd projection part (3b), and the length of the major axis direction of the said cyclic | annular 2nd projection part (1c) is X2, short. When the axial length is Y2 and the distance between the annular first protrusion 1c and the annular second protrusion 3b is A, A <(X2-Y2) / 2 can be established.

  The said structure WHEREIN: The said cyclic | annular 2nd projection part (3b) is located in an outer peripheral side rather than the said 1st cyclic | annular projection part (1c), and the long-axis direction length of the said cyclic | annular 1st projection part (1c) is X1, short. When the axial length is Y1, and the distance between the annular first protrusion 1c and the annular second protrusion 3b is A, A <(X1-Y1) / 2 can be established.

  According to these configurations, even when the electrode external terminal rotates, the annular first protrusion 1c and the annular second protrusion 3b do not overlap. For this reason, the further rotation of the electrode external terminal 1 is suppressed.

  In the above configuration, when the thickness of the insulating gasket is W (mm), the height of the annular first protrusion (1c) and the annular second protrusion (3b) is 0.2 W to 0.7 W. There can be a certain configuration.

  In order to sufficiently obtain the effects of the annular first protrusion 1c and the annular second protrusion 3b, the height of these annular protrusions is preferably 0.2 W or more. On the other hand, if the height of the protrusions is too high, the force applied to the insulating gasket becomes too large and the terminal may be deformed. Therefore, the height of these annular protrusions should be 0.7 W or less. Is preferred.

  As described above, according to the present invention, it is possible to realize a sealed battery including a battery built-in type electrode external terminal that does not leak.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

[Embodiment 1]
FIG. 1 is a perspective view of a battery according to the present embodiment, FIG. 2 is a diagram illustrating a structure of an electrode external terminal used in the battery according to the present embodiment, and FIG. 3 is a diagram illustrating the battery according to the present embodiment. FIG. 4 is a perspective view of a main part of the battery according to the present embodiment, and FIG. 5 is an enlarged cross-sectional view of the main part of the battery according to the present embodiment. FIG. 6 is a plan perspective view of the terminal fixing portion of the battery according to the present embodiment.

  In the battery according to the present embodiment, as shown in FIG. 1, a spiral electrode body (not shown) in which positive and negative electrodes are wound in a spiral shape and a nonaqueous electrolyte are housed in an outer can 10. The opening of the outer can 10 is sealed by the sealing plate 3. Further, the positive and negative electrode external terminals 1 protrude from the sealing plate 3, respectively.

  As shown in FIG. 2, the electrode external terminal 1 includes a columnar insertion portion 1a and a flange portion 1b. An elliptical annular first protrusion 1c surrounding the columnar insertion portion 1a is formed on the lower surface of the flange portion 1b. When the thickness of the insulating gasket is W (mm), the height of the annular first protrusion 1c is 0.4W.

  As shown in FIG. 3, the sealing plate 3 is provided with a through hole 3a and a recess into which the insulating gasket is fitted. In addition, an elliptical annular second protrusion 3b surrounding the through hole 3a is provided on the upper surface of the recess. The height of the annular second protrusion 3b is 0.4W.

  As shown in FIGS. 4 and 5, the columnar insertion portion 1a of the electrode external terminal 1 has through holes 2a, 3a, 4a provided in the insulating gasket 2, the sealing plate 3, the insulating plate 4, and the current collecting plate 5, respectively. The columnar insertion portion 1 a of the electrode external terminal 1 is fixed to the sealing plate 3 by being inserted into 5 a and fixed by caulking.

  As shown in FIG. 6, the annular first protrusion 1c and the annular second protrusion 3b are arranged at positions that do not overlap each other (the annular first protrusion 1c is located on the outer periphery, 2 projections 3b are located on the inner periphery). In addition, the long axis direction length of the annular first protrusion 1c is X1, the short axis direction length is Y1, the long axis direction length of the annular second protrusion part 3b is X2, the short axis direction length is Y2, and the ring When the distance between the first protrusion 1c and the annular second protrusion 3b is A, A <(X2-Y2) / 2 is established.

  Polypropylene, polyphenylene sulfide, polyether ether ketone, a copolymer of tetrafluoroethylene and perfluoroalkoxyethylene, or the like can be used as a constituent material for an insulating gasket or an insulating plate. Moreover, aluminum, aluminum alloy, iron, stainless steel, copper, copper alloy, nickel etc. can be used as a material of an electrode external terminal, a sealing board, and an exterior can.

  Next, a method for assembling the battery of the present invention will be described with reference to FIG. First, a spiral electrode body is produced by a known method. At this time, it arrange | positions so that a positive electrode current collecting plate may protrude from one edge part, and a negative electrode current collecting plate may protrude from the other edge part.

  Next, the insulating plate 2 made of polyetheretherketone and the electrode external terminal 1 made of aluminum are connected to the sealing plate 3 from the outer surface of the battery, and the insulating plate made of polyetheretherketone is formed from the inner surface of the battery. 4 and the sealing body lead 5 made of aluminum are overlapped. The insertion portion 1a of the electrode external terminal 1 passes through the through holes 2a, 3a, 4a, 5a of the insulating gasket 2, the sealing plate 3, the insulating plate 4, and the current collecting plate 5.

  The gasket 2 and the insulating plate 4 are compressed from the vertical direction (vertical direction) from both the tip end portion of the columnar insertion portion 1a of the electrode external terminal 1 and the flange portion 1b until a predetermined compression rate is obtained (caulking process) and fixed. (See FIG. 5).

  For the battery according to the present embodiment having this structure, a torque was applied to the electrode external terminal 1 to examine the torque necessary for the electrode external terminal 1 to start rotating. At the same time, an annular first protrusion and an annular second protrusion are not formed (Comparative Example 1), an annular first protrusion is not formed (Comparative Example 2), and an annular second protrusion. Is formed (Comparative Example 3), and the first annular protrusion and the second annular protrusion have a perfect circle shape (Comparative Example 4), and this is also tested in the same manner. Went. As a result, the battery of the present invention is 3.0 times or more compared to Comparative Example 1, 2.0 times or more compared to Comparative Example 2, 2.0 times or more compared to Comparative Example 3, and compared to Comparative Example 4. A torque of 1.5 times or more was required. From this, it can be seen that in the battery according to the present embodiment, the electrode external terminal 1 is more difficult to rotate than the conventional battery, and the risk of liquid leakage due to the rotation of the electrode external terminal is extremely low.

[Embodiment 2]
FIG. 7 is a diagram showing the structure of the electrode external terminal used in the battery according to the present embodiment, and FIG. 8 is a diagram showing the structure of the terminal fixing portion of the sealing plate used in the battery according to the present embodiment. 9 is an enlarged cross-sectional view of a main part of the battery according to the present embodiment, and FIG. 10 is a plan perspective view of a terminal fixing portion of the battery according to the present embodiment.

  In the present embodiment, as shown in FIG. 10, the annular first protrusion 1c is located on the inner periphery, the annular second protrusion 3b is located on the outer periphery, and the length of the annular first protrusion 1c in the major axis direction is shown. X1, the length in the short axis direction Y1, the length in the long axis direction of the annular second protrusion 3b is X2, the length in the short axis direction Y2, and the first ring protrusion 1c and the ring second protrusion 3b. Assuming that the distance is A, it is the same as in the first embodiment except that A <(X1-Y1) / 2 is satisfied.

  In the above embodiment, the elliptical annular first protrusion as shown in FIG. 2 is provided, but the rounded rectangle as shown in FIG. 11A and the track as shown in FIG. The shape, a polygon as shown in FIG. 11C, or an indefinite shape as shown in FIG. Similarly, the annular second protrusion can be a rounded rectangle, a track shape, a polygon, or an indeterminate shape.

  As described above, according to the present invention, it is possible to realize a sealed battery that is unlikely to cause liquid leakage, and therefore, the industrial significance is great.

FIG. 1 is a perspective view of the battery according to the first embodiment. 2A and 2B are diagrams showing an electrode external terminal according to the first embodiment, in which FIG. 2A is a front view and FIG. 2B is a bottom view. 3A and 3B are diagrams illustrating a terminal fixing portion of the sealing plate according to the first embodiment, in which FIG. 3A is a cross-sectional view and FIG. 3B is a plan view. FIG. 4 is a main part disassembly perspective view of the battery according to the first exemplary embodiment. FIG. 5 is an enlarged cross-sectional view of a main part of the battery according to the first embodiment. FIG. 6 is a plan perspective view of the terminal fixing portion of the battery according to the first embodiment. 7A and 7B are diagrams showing an electrode external terminal according to the second embodiment. FIG. 7A is a front view and FIG. 7B is a bottom view. 8A and 8B are diagrams showing a terminal fixing portion of the sealing plate according to the second embodiment, in which FIG. 8A is a cross-sectional view and FIG. 8B is a plan view. FIG. 9 is an enlarged cross-sectional view of a main part of the battery according to the second embodiment. FIG. 10 is a plan perspective view of the terminal fixing portion of the battery according to the second embodiment. FIG. 11 is a bottom view showing a modification of the electrode external terminal. FIG. 12 is a perspective view showing a state in which a plurality of (three) batteries are connected in series.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrode external terminal 1a Insertion part 1b Eaves part 1c Annular 1st projection part 2 Insulation gasket 3 Sealing plate 3a Through-hole 3b Annular second projection part 4 Insulation board 5 Current collecting board 10 Exterior can

Claims (6)

An electrode external terminal (1) having at least a flange portion (1b) and a columnar insertion portion (1a);
An insulating gasket (2) provided with a through hole (2a) into which the columnar insertion portion (1a) is inserted;
A sealing plate (3) provided with a through hole (3a) into which the columnar insertion portion (1a) is inserted;
A sealed battery in which a columnar insertion portion (1a) of the electrode external terminal is communicated with the two through holes (2a, 3a) and fixed to the sealing plate (3) via an insulating gasket (2). ,
The flange portion (1b) of the columnar insertion portion is formed with a non-round circular first protrusion (1c) surrounding the columnar insertion portion (1a) on the surface in contact with the insulating gasket (2),
The sealing plate (3) is formed with a non-circular circular second protrusion (3b) surrounding the through hole (3a) on the surface facing the flange (1b),
When the sealed battery is seen through from a direction perpendicular to the sealing plate (3), the annular first protrusion (1c) and the annular second protrusion (3b) do not overlap.
A sealed battery characterized by that. The sealed battery according to claim 1,
The annular first protrusion (1c) is formed in an elliptical shape, a track shape or a rounded rectangular shape,
A sealed battery characterized by that. The sealed battery according to claim 1,
The annular second protrusion (3b) is formed in an elliptical shape, a track shape, or a rounded rectangular shape,
A sealed battery characterized by that. The sealed battery according to claim 1,
The annular first protrusion (1c) is positioned on the outer peripheral side of the annular second protrusion (3b), and the distance between the annular first protrusion (1c) and the annular second protrusion (3b) is defined as A. ,
When the major axis direction length of the annular second protrusion (1c) is X2, and the minor axis direction length is Y2,
A <(X2-Y2) / 2 is established,
A sealed battery characterized by that. The sealed battery according to claim 1,
The annular second protrusion (3b) is positioned on the outer peripheral side of the annular first protrusion (1c), and the distance between the annular second protrusion (3b) and the annular first protrusion (1c) is A.
When the major axis direction length of the annular first protrusion (1c) is X1, and the minor axis direction length is Y1,
A <(X1-Y1) / 2 is established,
A sealed battery characterized by that. In the battery according to any one of claims 1 to 5, when the thickness of the insulating gasket is W (mm),
The height of the annular first protrusion (1c) and the annular second protrusion (3b) is 0.2W to 0.7W.
A sealed battery characterized by that.