JP2006351822A - Coin type electrochemical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable coin type electrochemical element of which the negative electrode and the positive electrode lead terminals are surely and precisely attached to an upper lid and a lower lid of the element, with a mounting area of a printed board reduced to a minimum. <P>SOLUTION: In the coin type electrochemical element, triangular positive and negative electrode lead terminals 12 and 13 are connected to outer surfaces of a lower lid 21 and an upper lid 20 with the side surface of the negative electrode lead terminal 13 connected to the upper lid 20 formed with a notch. Therefore, the mounting area of the printed board is minimum for precision high density mounting, even with the coin type electrochemical element of a small size, resulting in providing a coin type electrochemical element of high reliability. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coin-type electrochemical element having an external lead terminal used for surface mounting among electrochemical elements such as capacitors and batteries.

  Examples of this type of coin-type electrochemical element include an electric double layer capacitor and a button battery. FIG. 3 is a partially cutaway side view showing the configuration of the electric double layer capacitor 31 used for surface mounting. As shown in the figure, an anode-side polarizable electrode 34 made of an activated carbon electrode and a cathode-side polarizable electrode 35 are arranged to face each other with a separator 36 interposed therebetween. The cathode 37 is provided on the cathode-side polarizable electrode 35, and the lower lid 41 and the upper lid 40 are hermetically sealed with an insulating ring packing 42 interposed therebetween. The non-aqueous electrolyte 39 is filled in the container so that the pair of polarizable electrodes 34 and 35 and the separator 36 are satisfied. Next, the cathode lead terminal 33 is connected to the upper lid 40 and the anode lead terminal 32 is welded to the lower lid 41, so that the legs 43 mounted on the printed circuit board of the cathode lead terminal 33 face the anode lead terminal 32. It is bent.

  Further, in the button battery, the electrode with the separator interposed between the positive electrode and the negative electrode is accommodated in the two metal containers, and the external structure has the same configuration as the electric double layer capacitor. Yes.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2004-165537 A

  However, in the electric double layer capacitor, the space between the lower lid and the cathode lead terminal is wide open in order to avoid contact. Further, since the legs of the anode lead terminal and the cathode lead terminal are opposed to each other, a large mounting area of the printed circuit board has to be taken.

  In addition, the material used for the lower and upper lids of the coin-type electric double layer capacitor has been aluminum, stainless steel, or austenitic / ferrite duplex stainless steel having an aluminum layer on the inner surface. However, when a high voltage charge of about 2.8 V is performed, corrosion such as pitting corrosion occurs on the lower lid side, and there is a problem that a reliable coin-type electrochemical device cannot be obtained.

  The present invention solves such a conventional problem, and can accurately and reliably attach the cathode and anode lead terminals to the upper and lower lids of the coin-type electrochemical element and minimize the mounting area of the printed circuit board. An object of the present invention is to provide a coin-type electrochemical device that can be used and has excellent reliability.

  In order to solve the above-described problems, the present invention particularly has a substantially triangular shape on the outer surface of the lower lid (anode portion) and the upper lid (cathode portion), and is partially on the side surface of the cathode lead terminal connected to the upper lid. It is a coin-type electrochemical element provided with a notch.

  The cathode lead terminal is a coin-shaped electrochemical element in which the cathode lead terminal has a U-shape and a portion of the cathode lead terminal to be mounted on the printed board is notched.

  In the present invention, the outer surfaces of the anode and the cathode lead terminal have a substantially triangular shape, and a part of the cathode lead terminal connected to the upper lid is provided with a notch, so that the cathode lead has a U shape. Thus, contact between the side surface of the lower lid and the cathode lead terminal can be avoided, and the mounting area on the printed circuit board can be minimized, so that high-density mounting is also possible. Further, the pitch between the anode lead terminal and the cathode lead terminal can be reduced.

  In addition, since the notch is provided in the portion of the cathode lead terminal that is to be mounted on the printed board, solder fillet cannot be formed, so that the coin-type electrochemical element body and the cathode terminal are not short-circuited.

  Further, since the material constituting the lower lid and the upper lid contains more Ni, Cr and Mo contained in the stainless material than the upper lid, the coin-type electrochemical device has a high voltage charging environment exceeding 2.8V. It has sufficient corrosion resistance.

  Hereinafter, an embodiment of the present invention will be described in detail.

FIG. 1 is a partially cutaway side view showing the configuration of a coin-type electrochemical element for surface mounting. In the figure, a coin-type electrochemical element 11 has an anode-side polarizable electrode 14 made of an activated carbon electrode and a cathode-side polarizable electrode 15 made of an activated carbon electrode facing each other with a separator 16 therebetween. The polarizable electrode 14 is provided with an anode current collector 17, and the cathode-side polarizable electrode 15 is provided with a cathode current collector 18. Then, a water-soluble binder solution (concentration: 50%) in which carbon black and carboxymethyl cellulose having an average particle size of 0.05 μm were dissolved as a conductivity-imparting agent was added 10: 2: 1. And then kneaded sufficiently with a kneader to form the kneaded product into pellets, which are then dried in the atmosphere at 100 ° C. for 1 hour, and then separated between the two pellets. A pair of polarizable electrodes is obtained by interposing the electrolyte solution 19 of propylene carbonate: 75% by weight, EMIBF ₄ : 20% by weight, 4 ethylaluminium tetrafluoride: 5% by weight with the pair of polarizable electrodes. The electrodes 14 and 15 and the separator 16 are impregnated, and these are accommodated in a storage space portion constituted by the upper lid 20 and the lower lid 21.

  The upper lid 20 is made of SUS304 stainless steel, and the lower lid 21 is made of 8.29 wt% Ni, 18.12 wt% Cr and 0.19 wt% Mo contained in the stainless steel SUS304. ing.

  Next, the ring packing 22 having electrical insulation is disposed between the bent portion 23 formed on the outer peripheral portion of the upper lid 20 and the outer peripheral portion of the lower lid 21 to curl the front end portion 24 of the outer peripheral portion of the lower lid 21. As a result, a coin-type electrochemical device was manufactured by wrapping the bent portion 23 of the upper lid 20 with the ring packing 22 from the outside so as to provide an air-sealing port in the storage space that stores the pair of polarizable electrodes 14 and 15. .

  Next, a substantially triangular 0.10 mm-thick anode and cathode lead terminals 12 and 13 are welded to the surface of the lower lid 21 and the surface of the upper lid 20, respectively.

  The cathode lead terminal 13 is attached in parallel with the anode lead terminal 12, and the cathode lead terminal 13 is bent so as to have a U-shape, and the anode lead terminal and the mounting surface are connected in the same direction. Is done. At this time, since the notch portion is provided in the side surface portion of the cathode lead terminal 13, it can be brought close to the side surface of the lower lid 21 and the overall dimensions can be reduced. In addition, it is preferable that the side surface of the lid 21 serving as the side surface portion of the cathode lead terminal 13 has a gap of 1.0 to 1.5 mm.

  In the above configuration, the anode lead terminal 12 and the cathode lead terminal 13 have a substantially triangular shape, and a part of the cathode lead terminal 13 connected to the upper lid 20 is provided with a notch. Thus, the lower lid 21 of the coin-type electrochemical element 11 for surface mounting can be reliably connected without contacting the cathode lead terminal 13, and the mounting area of the printed circuit board can be minimized. .

  In addition, since the material of the lower lid 21 is different from that of the upper lid 20, it does not corrode even if it is charged at a high voltage of 3.3V, so that a product with excellent reliability can be obtained. .

  In this embodiment, the coin-type electrochemical element has been described. However, the coin-type electrochemical element can also be used for a button battery or the like.

  The present invention particularly relates to a coin-type electrochemical device having an external lead terminal used for surface mounting. Since this method can minimize the mounting surface on a printed circuit board, it can be used for power supplies such as mobile phones and digital cameras. The circuit portion as a backup or auxiliary power source can be reduced in size.

The partially cutaway side view which shows the structure of the coin-type electrochemical element for surface mounting in one embodiment of this invention The perspective view which shows the structure of the coin-type electrochemical element for surface mounting in one embodiment of this invention Partially cutaway side view showing the configuration of a conventional coin-type electric double layer capacitor for surface mounting

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Coin type electrochemical element 12 Anode lead terminal 13 Cathode lead terminal 14, 15 Polarization electrode 16 Separator 17, 18 Current collector 19 Electrolyte 20 Upper lid 21 Lower lid 22 Ring packing 23 Bending part 24 Tip part

Claims (4)

An element in which a pair of electrodes are arranged to face each other via an insulating separator, a lower lid (anode side) in which the element is impregnated and stored, and an opening of the lower lid are insulated. An upper lid (cathode side) hermetically sealed via ring packing, and an anode and a cathode lead terminal connected to the lower lid and the upper lid, and the outer surfaces of the anode and the cathode lead terminal have a substantially triangular shape; and A coin-type electrochemical device, wherein a part of the cathode lead terminal connected to the upper lid is partially cut out. The coin-type electrochemical device according to claim 1, wherein the cathode lead terminal has a U shape, and a portion to be mounted on the printed board is notched. The material which comprises the said upper cover and a lower cover consists of stainless steel materials, Ni, Cr, and Mo contained in the stainless material of the said upper cover and a lower cover are contained more than an upper cover. Coin-type electrochemical element. The Mo contained in the stainless material of the upper lid and the lower lid is 5 to 10% by weight, and Cr: 20 to 30% by weight, Ni: 20 to 40% by weight is included. Coin-type electrochemical element.

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