JP5978970B2 - battery - Google Patents

Description

  The present invention relates to a battery such as a secondary battery, and more particularly to a structure around a connection portion of an external connection terminal.

  In patent document 1, the secondary battery provided with a current interruption part is shown. The current interrupting part is a pressure-sensitive deformation element (diaphragm) that deforms when the internal pressure of the housing reaches a predetermined value or more, and part of the current path from the current collector to the external connection terminal as the pressure-sensitive deformation element is deformed It is comprised from the shielding foil etc. which interrupt | block.

JP 2008-66255 A (refer to FIGS. 1 to 3 and 5)

  When providing the current interrupting part as described above, high airtightness around the connection part of the external connection terminal and high positioning accuracy with respect to the pressure-sensitive deformation element, interrupting foil, etc. are required to accurately detect the internal pressure. Is done.

  FIG. 12 illustrates the problems of the conventional structure with respect to the above-described requirements. In the battery 101 according to this example, a sealing body 103 and an external connection terminal 104 are disposed in the opening of the housing 102. A space between the sealing body 103 and the external connection terminal 104 is sealed with an upper sealing material 105.

  A current collector 108 is disposed inside the housing 102. Between the current collector 108 and the sealing body 103, a current interrupting part 110 and a sealing body lead 111 are arranged. The current interruption unit 110 includes a pressure-sensitive deformation element 115 and an interruption foil 116. The sealing body lead 111 is in contact with the blocking foil 116 and the external connection terminal 104. The current held by the current collector 108 is transmitted to the external connection terminal 104 via the blocking foil 116, the pressure-sensitive deformation element 115, and the sealing body lead 111.

  Between the sealing body 103 and the sealing body lead 111 is sealed with an intermediate sealing material 120. A current collector holder 121 is disposed between the sealing body 103, the current collector 108, the pressure-sensitive deformation element 115, and the shielding foil 116. The sealing body 103 is formed with convex portions 125 and 126 for improving the sealing performance. The upper sealing material 105 and the intermediate sealing material 120 are in contact with each other, and the intermediate sealing material 120 and the current collector holder 121 are in contact with each other.

  At the time of assembly, the sealing body 103 is pressed against the sealing body lead 111 side. Thereby, the intermediate sealing material 120 receives a large pressure from the lower surface portion of the sealing body 103 including the convex portion 126, and is compressed in the vertical direction and expanded in the horizontal direction. Therefore, the current collector holder 121 receives pressure so as to be deformed or displaced outward as indicated by a two-dot chain line in FIG. Due to the deformation or displacement of the current collector holder 121, the pressure-sensitive deformation element 115 and the blocking foil 116 are displaced. In particular, the barrier foil 116 is easily broken due to its function, and thus is easily affected by such a displacement.

  Therefore, an object of the present invention is to achieve both sufficient airtightness and high positioning accuracy with respect to a current interrupting portion and the like.

  One aspect of the present invention is an external connection terminal that is connected to a current collector housed in a housing and the current collector through a current path formed in the housing, and a part of the external connection terminal is exposed to the outside of the housing. A sealing body that seals the opening of the casing, a sealing body lead that is disposed on the inner side of the casing with respect to the sealing body, and forms a part of the current path, and a part of the current path. And a pressure-sensitive deformation element that deforms according to the internal pressure of the housing, and normally forms a part of the current path, and the current path is broken by breaking when the pressure-sensitive deformation element is deformed by a predetermined amount or more. A sealing portion configured to include a first sealing material and a second sealing material in which a portion disposed between the sealing foil to be blocked and the sealing body and the sealing body lead is disposed at a predetermined interval. A battery comprising:

  According to the said aspect, the expansion | extension to the horizontal direction of the 1st sealing material at the time of an assembly | attachment is absorbed by a predetermined space | interval. As a result, even if the first sealing material is strongly compressed to improve the sealing performance, the extension is not transmitted to the second sealing material, which adversely affects the positioning of the pressure-sensitive deformation element, the shielding foil, etc. Never give.

  In addition, in the portion of the sealing body lead that sandwiches the first sealing material and the second sealing material together with the sealing body, the outer portion is inclined toward the sealing body with respect to the central portion before assembly. Also good.

  The sealing body includes a convex portion projecting toward the sealing body lead, the first sealing material abuts on the convex portion, and the second sealing material includes a current collector holder and It may be in contact or integrated.

  The first sealing material may be in contact with or integrated with an upper sealing material disposed between the external connection terminal and the sealing body.

  According to the present invention, it is possible to achieve both sufficient airtightness and high positioning accuracy with respect to the current interrupting portion and the like.

4 is a partial cross-sectional view showing a structure around a connection portion of an external connection terminal of the battery according to Embodiment 1. FIG. 3 is a partial cross-sectional view for illustrating a method for calculating a predetermined interval of the battery according to Embodiment 1. FIG. FIG. 3 is a cross-sectional view schematically showing a sealing body lead according to the first embodiment. It is sectional drawing which shows schematically the electric current interruption part immediately after assembling an electric current interruption part using the sealing body lead shown in FIG. It is sectional drawing which shows schematically the electric current interruption part after assembling a electric current interruption part using the sealing body lead shown in FIG. 3, and predetermined time passed. FIG. 6 is a cross-sectional view schematically showing a sealing body lead of a second embodiment. It is a figure for demonstrating the process at the time of assembling an electric current interruption | blocking part using the sealing body lead shown in FIG. It is a figure for demonstrating the process at the time of assembling an electric current interruption | blocking part using the sealing body lead shown in FIG. It is a figure for demonstrating the process at the time of assembling an electric current interruption | blocking part using the sealing body lead shown in FIG. It is sectional drawing which shows the other sealing body lead roughly. It is sectional drawing which shows the other sealing body lead roughly. It is a partial cross section figure of the battery for demonstrating the conventional problem.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a structure around the connection portion of the external connection terminal 4 of the battery 1 according to Embodiment 1 of the present invention. The battery 1 is a secondary battery, and includes a housing 2, a current collector 3, an external connection terminal 4, a sealing body 5, a sealing body lead 6, a pressure-sensitive deformation element 7, a shielding foil 8, and a plurality of sealing materials 11 and 12. , 13 and a current collector holder 14.

  The housing 2 is a hollow container made of an aluminum alloy or the like that constitutes the outer shell of the battery 1. The current collector 3 is housed in the housing 2 and is connected to an electrode that contacts the electrolytic solution.

  The external connection terminal 4 is electrically connected to the current collector 3 via a current path, which will be described later, in the housing 2, and a part of the external connection terminal 4 is exposed to the outside of the housing 2.

  The sealing body 5 is a member that seals the opening of the housing 2. Protrusions 9 and 10 for improving the sealing performance are formed at the end of the sealing body 5.

  The sealing body lead 6 is a member disposed below the sealing body 5 (inside the housing 2), and is made of a conductive material. The sealing body lead 6 constitutes a part of a current path that electrically connects the current collector 3 to the external connection terminal 4.

  The pressure-sensitive deformation element 7 is a diaphragm or the like and deforms according to the internal pressure of the housing 2. Specifically, when the pressure in the portion below the pressure-sensitive deformation element 7 in the housing 2 (inside the housing 2) exceeds a predetermined value, as shown by the two-dot chain line in FIG. Transforms into The pressure-sensitive deformation element 7 is made of a conductive material and constitutes a part of the current path.

  The shielding foil 8 is in contact with and fixed to the current collector 3 and the pressure-sensitive deformation element 7. The shielding foil 8 is made of a conductive material, and normally forms part of the current path. However, as described above, when the internal pressure of the housing 2 becomes a predetermined value or more and the pressure-sensitive deformation element 7 is deformed upward, the blocking foil 8 is broken and the current path is blocked. That is, the current path is blocked by the action of the pressure-sensitive deformation element 7 and the blocking foil 8.

  Each sealing material 11, 12, and 13 is a member for ensuring the airtightness between each said component. Specifically, the upper sealing material 11 disposed between the external connection terminal 4 and the sealing body 5, the first intermediate sealing material 12 disposed between the sealing body 5 and the sealing body lead 6, and the second intermediate material. There is a sealing material 13. A current collector holder 14 is disposed between the sealing body 5, the current collector 3, the pressure-sensitive deformation element 7, and the blocking foil 8.

  As described above, in the present embodiment, the portion that seals between the sealing body 5 and the sealing body lead 6 is divided into the first intermediate sealing material 12 and the second intermediate sealing material 13. . A predetermined distance A is secured between the first intermediate sealing material 12 and the second intermediate sealing material 13.

  Further, the convex portion 9 formed on the sealing body 5 and projecting downward is in contact with the first intermediate sealing material 12. The first intermediate sealing material 12 is in contact with the upper sealing material 11. The second intermediate sealing material 13 is in contact with the current collector holder 14. The current collector holder 14 is in contact with the pressure-sensitive deformation element 7 and the shielding foil 8 and directly affects the positioning thereof.

  Further, through holes 21 and 22 are formed in the current collector 3 and the current collector holder 14 so that the internal pressure of the housing 2 is transmitted to the pressure-sensitive deformation element 7.

  With the above configuration, the horizontal extension (see arrow D in FIG. 1) of the first intermediate seal material 12 during assembly is absorbed by the predetermined interval A. Thus, the extension of the first intermediate sealing material 12 does not change the second intermediate sealing material 13, and the current collector holder 14 that directly affects the positioning of the pressure-sensitive deformation element 7, the shielding foil 8, and the like. Does not fluctuate. As a result, it is possible to achieve both sufficient airtightness and high positioning accuracy with respect to the pressure-sensitive deformation element 7, the shielding foil 8, and the like. In the present embodiment, the second intermediate sealing material 13 and the current collector holder 14 are separate from each other, but similar effects can be obtained even if they are integrated.

  FIG. 2 is a diagram for illustrating a method of calculating the predetermined interval A. In the figure, X is the width of the portion corresponding to the convex portion 9 of the first intermediate seal material 12 before assembly (compression), and X ′ is X of the first intermediate seal material 12 after assembly. , Y is the thickness of the portion corresponding to the convex portion 9 of the first intermediate sealing material 12 before assembly, and Y ′ is the thickness of the first intermediate sealing material 12 after assembly. The thickness Z corresponding to Y indicates the length from the end of the first intermediate sealing material 12 to the end of the sealing body 5 (convex portion 9) before assembly.

  From the above definition, the following expressions (1) to (3) are satisfied.

  (Poisson's ratio) = (lateral strain) / (longitudinal strain) = ((X′−X) / X) / ((Y−Y ′) / Y) (1)

  X′−X (length extending in the lateral direction) = (Poisson's ratio) × X × ((Y−Y ′) / Y) (2)

  Predetermined interval A ≧ (X′−X) = (Poisson's ratio) × X × ((Y−Y ′) / Y) (3)

  By setting the predetermined interval A based on the above formula (3), the extension of the first intermediate seal material 12 during assembly is used to position the current collector 3, the pressure-sensitive deformation element 7, the shielding foil 8, and the like. A structure that does not adversely affect the structure can be reliably constructed.

Embodiment 2. FIG.
FIG. 3 is a cross-sectional view schematically showing the sealing body lead 6 of the first embodiment. FIG. 4 schematically shows the current interrupting part immediately after assembling the current interrupting part using the sealing body lead 6. FIG. 5 schematically shows the current interrupting unit after a predetermined time has elapsed since the current interrupting unit was assembled using the sealing body lead 6.

  Incidentally, the current interrupting unit shown for explaining the present embodiment is slightly different in configuration from the current interrupting unit of the first embodiment, but the basic principle is the same. Specifically, a space R1 surrounded by the cap 15, the sealing body lead 6, and the pressure-sensitive deformation element 7 is formed. The space R2 surrounded by the pressure-sensitive deformation element 7, the current collector holder 14, and the shielding foil 8 communicates with the space inside the battery, although not specifically illustrated. The space inside the battery is maintained in an airtight state by the pressure-sensitive deformation element 7. When the pressure inside the battery rises, the pressure-sensitive deformation element 7 is pushed upward, and the connection state between the pressure-sensitive deformation element 7 and the shielding foil 8 is released.

  As shown in FIG. 1 and FIG. 3, a portion (a sandwiching portion) 6 a that sandwiches the first intermediate sealing material 12 and the second intermediate sealing material 13 together with the sealing body 5 in the sealing body lead 6 is formed substantially horizontally. . At this time, if the first intermediate sealing material 12 and the second intermediate sealing material 13 are formed of a member having a strong elastic force such as a resin, the current interrupting portion is assembled using the sealing body lead 6 as shown in FIG. In this case, the sandwiching portion 6a of the sealing body lead 6 is pushed down by the reaction force of the first intermediate sealing material 12 sandwiched between the sealing body 5 and the sealing body lead 6, and the second intermediate sealing material 13 is pressed down. And a sealing body lead 6. Then, as shown in FIG. 5, the second intermediate sealing material 13 is moved downward by an external force such as vibration, and the current collector holder 14 joined to the second intermediate sealing material 13 is moved downward. The load acts on the shielding foil 8 by moving.

  Therefore, in this embodiment, the shape of the sealing body lead is devised. FIG. 6 is a cross-sectional view schematically showing the sealing body lead 16 of the present embodiment. 7-9 is a figure for demonstrating the process at the time of assembling an electric current interruption | blocking part using the sealing body lead | read | reed 16 of this Embodiment.

  As shown in FIG. 6, a portion (sandwich portion) 16 a that sandwiches the first intermediate sealing material 12 and the second intermediate sealing material 13 together with the sealing body 5 in the sealing body lead 16 of the present embodiment is centered before assembly. It inclines to the sealing body 5 side toward an outward part from a part. That is, the sealing body lead 16 is sandwiched so as to resist the reaction force of the first intermediate sealing material 12 and to support the second intermediate sealing material 13 and the current collector holder 14 when assembled. The portion 16a is warped in advance.

  When assembling the current interrupting portion using such a sealing body lead 16, first, as shown in FIG. 7, the sealing body lead 16 is disposed on the first jig P <b> 1, and further, the first sealing body lead 16 is placed on the first sealing body lead 16. The intermediate sealing material 12 and the second intermediate sealing material 13 are arranged at a predetermined interval. Then, the sealing body 5 is disposed on the first intermediate sealing material 12 and the second intermediate sealing material 13, and the upper sealing material 11 is further disposed on the sealing body 5. In addition, an external terminal 17 is arranged on the upper sealing material 11.

  Next, as shown in FIG. 8, the upper part of the sealing body lead 16 is caulked with the second jig P2, and the first intermediate sealing material 12 and the second caulking part 16b are sandwiched between the caulking part 16b and the sandwiching part 16a. The intermediate sealing material 13, the sealing body 5, the upper sealing material 11, and the external terminal 17 are sandwiched.

  Thereafter, as shown in FIG. 9, the sealing body lead 16 and the pressure-sensitive deformation element 7 are joined, and the cap 15 is fitted into the upper opening of the sealing body lead 16, and the cap 15, the sealing body lead 16 and the pressure-sensitive deformation are formed. A space R1 surrounded by the element 7 is formed. Then, when the current collector holder 14 to which the shielding foil 8 is attached is joined to the second intermediate sealing material 13 and the pressure-sensitive deformation element 7 and the shielding foil 8 are joined, a current interrupting portion can be configured.

  Thus, the sealing body lead 16 resists the reaction force of the 1st intermediate | middle sealing material 12 by making the sandwiching part 16a of the sealing body lead 16 into the shape inclined in advance toward the sealing body 5 side beforehand. In addition, the second intermediate sealing material 13 and the current collector holder 14 can be supported. Therefore, it can suppress that a clearance gap produces between the insertion part 16a of the sealing body lead | read | reed 16, and the 1st intermediate | middle sealing material 12 and the 2nd intermediate | middle sealing material 13, and interrupts | blocks as a result as an unexpected timing. It is possible to suppress the load from acting on the foil 8.

  In particular, even if the first intermediate seal material 12 and the second intermediate seal 13 are separately disposed as the intermediate seal material, the present embodiment is not limited to the sealing performance by the first intermediate seal material 12 but the second Thus, the sealing performance by the intermediate sealing material 13 can be exhibited well, and the performance of the battery can be improved.

  Further, since the first intermediate sealing material 12 and the second intermediate sealing material 13 can be formed of resin or the like, the durability of the first intermediate sealing material 12 and the second intermediate sealing material 13 is improved. Can do.

  Further, for example, when the sealing body lead 16 is made of metal, it is possible to suppress a reduction in the reaction force that appears even in a high temperature environment.

  Note that the sealing body lead 16 shown in FIG. 6 and the like has a shape that inclines toward the sealing body 5 from the central portion toward the outer portion before assembly, but this is not restrictive. For example, like the sealing body lead 26 shown in FIG. 10, before the sandwiching portion 26a is assembled, it is warped toward the sealing body 5 from the central portion toward the outer portion, that is, the outer portion is more sealed than the central portion. The shape may be curved so as to be positioned on the body 5 side. Further, like the sealing body lead 36 shown in FIG. 11, the shape is substantially horizontal from the central portion to the middle portion toward the outer portion, and further inclined toward the sealing body 5 from the middle portion toward the outer portion. Good. In short, the sandwiched portion of the sealing body lead only needs to be arranged on the sealing body 5 side in the outer portion with respect to the central portion.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Battery 2 Housing | casing 3 Current collector 4 External connection terminal 5 Sealing body 6 Sealing body lead 6a Clamping part 7 Pressure-sensitive deformation element 8 Blocking foil 9, 10 Convex part 11 Upper sealing material 12 First intermediate sealing material 13 Second Intermediate sealing material 14 Current collector holder 15 Cap 16 Sealing body lead 16a Clamping portion 16b Caulking portion 17 External terminals 21, 22 Through hole 26 Sealing body lead 26a Clamping portion 36 Sealing body lead 36a Clamping portion A Predetermined interval P1 First interval Jig P2 Second jig R1, R2 space

Claims (4)

A housing,
An external connection terminal part is exposed to the outside of the housing,
And the sealing body to seal the opening of the housing, to have a open hole through which the external connection terminal is passed through,
A sealing body lead disposed on the inner side of the housing than the sealing body and electrically connected to the external connection terminal ;
A pressure-sensitive deformation element that is electrically connected to the sealing body lead and deforms according to the internal pressure of the housing;
Is electrically connected to the sensitive pressure deformable element during normal maintaining electrical connection with the previous SL sensitive pressure deformable element, before Symbol feeling and deformed by breaking when the sensitive and deformed element is deformed a predetermined amount or more A barrier foil for blocking electrical connection with the element ;
A current collector housed in the housing and electrically connected to the barrier foil;
Between the opposed surfaces of the central axis of the sealing member of the opening hole and the sealing member and the sealing member leads, first being spaced apart in a direction perpendicular to the central axis direction of the opening hole of the sealing body A sealing portion including one sealing material and a second sealing material;
A battery comprising: The part sandwiching the first sealing material and the second sealing material together with the sealing body in the sealing body lead is arranged such that the outer part is closer to the sealing body than the central part before assembly . The battery according to claim 1, wherein the battery is disposed in close contact with the first sealing material and the second sealing material after being assembled. The sealing body includes a convex portion protruding to the sealing body lead side,
The first sealing material is in contact with the convex portion,
The second sealing material is in contact with or integrated with the current collector holder;
The battery according to claim 1 or 2. The first sealing material is in contact with or integrated with an upper sealing material disposed between the external connection terminal and the sealing body.
The battery according to claim 3.

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