JP2009259970A - Electrochemical cell and surface mount electrochemical cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrochemical cell and a surface mount electrochemical cell that are airtight, reduce the diameter of a cap without reducing the amount of built-in active material and are miniaturized by that amount. <P>SOLUTION: In a base 11, a soft metal layer is formed on the outer periphery surface of a metal ring 14, and one lead 13 is passed and fixed to a pellet 12 stuck into the metal ring 14. A sheet-like active material 20 is connected to an inner lead 13b of the lead 13 and is electrically connected to a positive electrode active material sheet in the active material 20. An outer periphery surface in which the soft metal layer of the metal ring 14 is formed is forced into the open edge of a cap 30 to which an electrolyte has been injected so that the periphery of the active material 20 is surrounded. Also, a protruded electrode 35 is provided on the outer periphery surface of the cap 30 and is electrically connected to a negative electrode active material sheet of the active substance 20 via the cap 30, the metal ring 14, and the connection ring. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrochemical cell and a surface-mount electrochemical cell.

Electrochemical cells such as electric double layer capacitors are used in portable devices for memory backup. As a small package, a coin type is commonly used (see Patent Document 1).
JP 2002-190427 A

By the way, with the high functionality and miniaturization of portable devices, this type of electrochemical cell is also required to be further miniaturized.
However, even the smallest coin package has a size of about 4 mm. Furthermore, a package having a small diameter, for example, a size as small as about 1 mm has not been proposed. This is because the structure of the coin-type capacitor uses an insulating gasket to electrically insulate the positive electrode and the negative electrode.

  In addition, the external electrode terminal of the conventional conic type package has the external terminal attached to the positive electrode can and the negative electrode can with a laser or the like (see also Patent Document 1), which is caused by variations in the bending angle of the external terminal. Since it is inferior in coplanarity (coplanarity), there has been a problem that the cell can be mounted in a slanted state when mounted on a substrate.

  The present invention has been made to solve the above-described problems, and its purpose is to have a very high airtightness and to reduce the diameter of the cap without reducing the amount of the built-in active material. It is an object of the present invention to provide an electrochemical cell and a surface-mount electrochemical cell that can be formed.

  The electrochemical cell of the present invention includes a base having a metal lead penetrated and fixed to an insulating filler fixed in an annular metal ring having a soft metal layer formed on the outer peripheral surface thereof, and penetrating the insulating filler. A sheet-like electrode active material connected to the inner lead portion of the fixed lead, the inner lead portion and the metal ring being electrically connected to each other, and an electrode connected to the inner lead portion of the lead The outer peripheral surface of the ring is press-fitted so as to cover the periphery, and is tightly fixed to the base and has a covered cylindrical cap provided with an electrode on the outer peripheral surface, and an electrolyte filled in the cap. Have

  According to the electrochemical cell of the present invention, since the base (metal ring) is press-fitted into the cap, that is, the connection between the base and the cap is press-fitting between metals, the connecting operation becomes very simple.

  In addition, the cap fits a soft metal layer formed on the outer peripheral surface of the metal ring by press fitting. Therefore, the airtightness is very high as compared with a conventionally used resin gasket. Moreover, deterioration of quality can be suppressed even in a severe environment of high temperature and humidity. Furthermore, since the resin gasket used conventionally is not used, the diameter of the cap can be shortened without reducing the amount of the active material incorporated, and the electrochemical cell can be miniaturized accordingly.

  The base having such a structure can be manufactured with high productivity even if the outer diameter is reduced from about 0.5 mm to about 2 mm. Moreover, the cap which becomes a pair can also be manufactured with high mass productivity by deep drawing of a thin plate, for example, as will be described later.

  And an electrochemical cell is mounted in a printed circuit board by connecting the outer lead part of a lead, and the electrode of a cap, for example to the corresponding wiring formed in the printed circuit board, respectively.

  In this electrochemical cell, the soft metal layer formed on the outer peripheral surface of the metal ring may be a single metal of tin or silver, or tin / silver (SnAg) after forming a copper layer or a nickel layer as a base. , A metal film made of an alloy of gold / tin (AuSn) or tin / copper (SnCu) may be formed.

According to this, the cap can make the electrochemical cell very high airtightness by tightly fitting the soft metal layer formed on the outer peripheral surface of the metal ring.
In this electrochemical cell, the insulating filler fixed in the metal ring may be borosilicate glass or soda glass.

According to this, the lead is supported and fixed while being hermetically sealed with glass.
In this electrochemical cell, the metal ring and the lead may be FeNiCo alloy, iron-nickel alloy, or stainless steel.

  According to this, in the case of FeNiCo alloy and iron-nickel alloy, the thermal expansion coefficient of the lead, metal ring, and pellet constituting the base can be approximated. In addition, when stainless steel is selected, an airtight structure with excellent reliability can be achieved by designing the dimensions so that compressive stress of glass is applied.

In this electrochemical cell, the cap may be white and the surface thereof may be nickel (Ni) plated.
According to this, since white and white are excellent in spreadability, a covered cylindrical cap can be formed by deep drawing. Moreover, since the surface of the white cap with excellent corrosion resistance is plated with nickel, it is possible to prevent corrosion of the cap.

In this electrochemical cell, the inner lead portion of the lead in contact with the electrolytic solution may be coated with an aluminum film on the surface thereof.
According to this, corrosion can be prevented by coating the surface of the inner lead portion with aluminum.

In this electrochemical cell, the portion of the ring that contacts the electrolyte may be coated with an aluminum film.
According to this, corrosion can be prevented by coating aluminum on the surface of the metal ring in contact with the electrolyte.

  The surface mount type electrochemical cell of the present invention includes the above-described electrochemical cell, a first external electrode terminal connected to the outer lead portion of the lead protruding from the base that is closely fixed to the cap, and a base that is firmly fixed to the base. A second external electrode terminal connected to the electrode provided on the cap, covering the tightly fixed base and cap, and exposing the first external electrode terminal and a part of the second electrode terminal. Molded with resin.

  According to the surface mount type electrochemical cell of the present invention, the electrochemical cell is resin-molded so that a part of the external electrode terminal is exposed to the outside. High implementation becomes easy.

Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings.
FIG. 1 is an overall perspective view of a resin-molded surface-mounted electrochemical cell 1, and FIG. 2 is a cross-sectional view of the resin-molded surface-mounted electrochemical cell 1.

  The surface mount type electrochemical cell 1 is formed by molding the electrochemical cell 1 with a resin J such as an epoxy resin by insert molding. The surface mount type electrochemical cell 1 includes a positive external electrode terminal 2 as a first external electrode terminal electrically connected to an outer lead portion 13a of an electric double layer capacitor 10 as an electrochemical cell, and an electric double layer The negative external electrode terminal 3 as the second external electrode terminal is electrically connected to the protruding electrode 35 of the capacitor 10.

  The positive external electrode terminal 2 and the negative external electrode terminal 3 are resin-molded together with the electric double layer capacitor 10, and are molded so that a part thereof is exposed from the bottom surface 1a of the resin J of the surface-mounted electrochemical cell 1 that is resin-molded. Has been.

  In other words, the positive external electrode terminal 2 is formed in a U-shaped cross section, the upper piece 2a is electrically connected to the outer lead portion 13a by welding, and the lower piece 2b is exposed from the bottom surface 1a of the resin J. Further, the negative external electrode terminal 3 is formed in an L-shaped cross section, and is electrically connected by welding to the protruding electrode 35 fitted in the fitting recess 3a formed on the upper side, and the lower piece 3b is made of the resin J. It is exposed from the bottom surface 1a. At this time, the lower surface of the lower piece 2b of the positive external electrode terminal 2 and the lower surface of the lower piece 3b of the negative external electrode terminal 3 are flush with each other.

  In the surface mount type electrochemical cell 1, the lower piece 2b of the positive external electrode terminal 2 and the lower piece 3b of the negative external electrode terminal 3 exposed from the bottom surface 1a of the resin J are connected to the wiring formed on the printed circuit board P. As a result, the surface mount type electrochemical cell 1 is mounted on the printed circuit board P with high positional accuracy.

Next, the resin-molded electric double layer capacitor 10 will be described.
FIG. 3 is an overall perspective view showing the external appearance of the electric double layer capacitor 10, and FIG. 4 is an exploded perspective view of the electric double layer capacitor 10.

  3 and 4, the electric double layer capacitor 10 includes a base 11. The base 11 includes a pellet 12 as an insulating filler, a lead 13 made of a conductive material, and a metal ring 14.

  As shown in FIG. 5, the pellet 12 has a cylindrical shape, and its main body is closely fixed to the metal ring 14, and the outer peripheral surface of the pellet 12 is closely fixed to the inner peripheral surface of the metal ring 14 in an airtight state. Has been. A soft metal layer 15 made of soft metal is formed on the outer peripheral surface 14a of the metal ring 14 as shown in FIG. In this embodiment, the soft metal layer 15 is formed with a thickness of about 10 μm to 50 μm.

  The pellet 12 is formed with a through hole 12a penetrating through the center positions of the left and right side surfaces. The lead 13 is passed through the through hole 12a, and the lead 13 is tightly fixed to the through hole 12a in an airtight state.

  For convenience of explanation, in FIG. 4, the left side surface of the pellet 12 is referred to as an outer side surface 12b, and the right side surface of the pellet 12 is referred to as an inner side surface 12c. And about the lead 13 tightly fixed to the through hole 12a of the pellet 12, the part protruding from the outer side surface 12b of the pellet 12 is called the outer lead part 13a, and the part protruding from the inner side face 12c of the pellet 12 is called the inner lead part 13b. .

  An active material 20 is wound around the inner lead portion 13b. As shown in FIG. 7, the active material 20 includes a first separator 21, a second separator 22, a positive electrode active material sheet 23, and a negative electrode active material sheet 24. The first separator 21, the second separator 22, the positive electrode active material sheet 23, and the negative electrode active material sheet 24 are formed in a sheet shape. And the 1st separator 21, the negative electrode active material sheet 24, the 2nd separator 22, and the positive electrode active material sheet 23 are laminated | stacked in order.

  In addition, the vertical width and the horizontal width of the first separator 21 are formed longer than the vertical width and the horizontal width of the negative electrode active material sheet 24. The vertical width of the second separator 22 is formed between the vertical width of the first separator 21 and the vertical width of the negative electrode active material sheet 24, and the horizontal width of the second separator 22 is negative electrode active material sheet 24. And a length between the lateral width of the positive electrode active material sheet 23. Further, the vertical width of the positive electrode active material sheet 23 is formed to be the same length as the vertical width of the negative electrode active material sheet 24, and the horizontal width of the positive electrode active material sheet 23 is shorter than the horizontal width of the second separator 22. .

  At this time, as shown in FIG. 7, the negative electrode active material sheet 24 disposed between the first separator 21 and the second separator 22 is completely covered with the first separator 21, whereas the second separator It arrange | positions so that a part may be exposed from the both ends side of 22. FIG. One end of a strip-shaped connection electrode 25 is electrically connected to a position exposed from the second separator 22 on the right side of the negative electrode active material sheet 24.

Further, the positive electrode active material sheet 23 disposed on the surface of the second separator 22 opposite to the negative electrode active material sheet 24 side is disposed so as to be completely covered by the second separator 22.
Then, the active material 20 in which the first separator 21, the positive electrode active material sheet 23, the second separator 22, and the negative electrode active material sheet 24 are stacked in this order is wound around the inner lead portion 13 b provided on the base 11.

  More specifically, as shown in FIG. 7, the inner lead portion 13 b is brought into contact with the left end portion of the positive electrode active material sheet 23. From this state, the active material 20 composed of the first separator 21, the second separator 22, the positive electrode active material sheet 23, and the negative electrode active material sheet 24 is placed on the inner lead portion 13 b so as not to contact the metal ring 14 of the base 11. Wind and wrap.

  In the active material 20 wound around the inner lead portion 13b, the positive electrode active material sheet 23 and the negative electrode active material sheet 24 are completely covered by the first separator 21 and the second separator 22 and are in direct contact with each other. There is nothing.

  After winding, the other end of the strip-like connection electrode 25 having one end electrically connected to the negative electrode active material sheet 24 is electrically connected to the surface 14b of the metal ring 14 by spot welding. Therefore, the inner lead portion 13 b is electrically connected to the positive electrode active material sheet 23 of the active material 20, and the metal ring 14 is electrically connected to the negative electrode active material sheet 24 of the active material 20.

  The base 11 around which the active material 20 is wound is attached with a covered cylindrical cap 30 containing an electrolytic solution 31 (see FIG. 9). The cap 30 has a covered cylindrical shape made of a metal material rich in elasticity. The covered cylindrical cap 30 is tightly fixed to the base 11 without leaking the electrolytic solution 31 contained in the cap 30 by press-fitting the outer peripheral surface 14a of the ring 14 of the base 11 into the open end 30a.

  More specifically, as shown in FIG. 6, when the active material 20 is wound around the base 11 and pressed into the cap 30 containing the electrolytic solution 31, the cap 30 has an opening end 30 a of the ring 14. The soft metal layer 15 formed on the outer peripheral surface 14a is press-fitted while being fitted. Therefore, the space formed by the base 11 and the cap 30 is kept airtight, so that the electrolytic solution 31 does not leak.

Further, the center position of the tip of the cap 30 is electrically connected by welding a cylindrical protruding electrode 35 with a laser or the like.
Next, the manufacturing method of the surface mount type electrochemical cell 1 will be described.

(Base 11)
For example, a borosilicate glass powder is put into a mold to form a precursor of pellets 12 having through holes 12a. Also, a lead 13 is prepared to be inserted into the through hole 12a. Further, a metal ring 14 is prepared that is tightly fixed to the outer peripheral surface of the pellet 12. It is preferable that the lead 13 and the metal ring 14 approximate the pellet 12 in a wide range of thermal expansion coefficient. For example, Kovar (FeNiCo alloy) or iron-nickel alloy is a candidate.

The glass is not limited to borosilicate glass, and may be soda glass. Here, soda glass can be selected from soda lime glass and soda barium glass.
Furthermore, stainless steel can be used for the material of the metal ring 14 and the lead 13. In this case, it is preferable to adopt a structure in which compressive stress is applied to the glass depending on the dimension design of the member. Thereby, the long-term reliability of glass is securable.

  The precursor of the pellet 12, the lead 13, and the metal ring 14 are assembled into a predetermined shape using a jig, and then fired to form an integrated object (base 11). Thereby, between the lead 13 and the pellet 12 and between the pellet 12 and the metal ring 14 are hermetically sealed and fixed.

  Next, after removing the jig, the soft metal layer 15 is formed on the outer peripheral surface 14a of the metal ring 14 by plating. For plating, after forming a film such as a copper layer or a nickel layer on the base with a thickness of about 5 μm, any of tin, tin copper alloy, tin bismuth alloy, tin silver alloy, gold-tin alloy, etc. is about 5 μm to 50 μm. The thickness is formed. If the thickness is 5 μm or less, the film thickness is insufficient and airtightness cannot be maintained. If it is 50 μm or more, press-fitting becomes difficult. The thickness is preferably 10 μm to 20 μm. And after washing | cleaning, the base 11 is completed by aging.

  The surface of the inner lead portion 13b is preferably coated with an aluminum film of several tens of μm. The purpose is to prevent corrosion. Similarly, the surface 14b of the metal ring 14 in contact with the electrolytic solution 31 is preferably coated with an aluminum film of about several μm. This is because the metal ring 14 forms one pole when the outer lead portion 13a makes a false contact with the metal ring 14. In this case, corrosion can be prevented by covering the surface 14 a of the metal ring 14 in contact with the electrolytic solution 31 with an aluminum film.

(Cap 30)
The covered cylindrical cap 30 is formed by deep drawing. As the material of the cap 30, a white having excellent spreadability, easy to deeply draw into a cylindrical shape, and excellent in corrosion resistance was selected. The cap 30 was formed by pressing a white plate material (thickness: about 0.1 mm) with a press. Thereafter, the cap 30 is completed by applying nickel plating to the inner and outer surfaces with a thickness of about 3 to 5 μm.

Further, the protruding electrode 35 is welded to the center position of the tip of the cap 30 with a laser or the like.
(Assembly of capacitor)
First, the active material 20 is wound around the inner lead portion 13 b of the base 11. After winding, the other end of the strip-like connection electrode 25 extending from the terminal negative electrode active material sheet 24 is electrically connected to the surface 14b of the ring 14 by spot welding.

  Subsequently, the end of the wound active material 20 is covered with a separator sheet so as not to be short-circuited. And it winds with insulating tapes, such as a polyimide resin, from the outer side so that the active material 20 of the wound state may be clamped. Thereafter, the entire outside of the wound active material 20 is covered with a separator sheet, or covered with an insulating film.

Next, as shown in FIG. 8, the wound active material 20 is immersed in an electrolytic solution 31 stored in a tank 32 to promote gas generation and the like.
Subsequently, a predetermined amount of electrolytic solution 31 is injected into the cap 30. Then, as shown in FIG. 9, after aligning the base 11 around which the active material 20 is wound and the cap 30 into which the electrolytic solution 31 is injected, the base 11 is press-fitted into the open end 30 a of the cap 30, The electrolytic solution 31 is sealed. The press-fitting at this time is cold press-fitting. Note that this operation may be performed in the electrolytic solution 31.

And after washing | cleaning, after testing the electrical property of a capacitor, the electric double layer capacitor 10 is completed.
(Molding of electric double layer capacitor 10 with resin)
First, as shown in FIG. 10, a lead frame 41 in which a positive electrode terminal portion 42 that becomes the positive electrode external electrode terminal 2 and a negative electrode terminal portion 43 that becomes the negative electrode external electrode terminal 3 form a plurality of pairs. Prepare. The plate thickness of the lead frame 41 is preferably about 100 μm to 150 μm, and the material is preferably similar in thermal expansion coefficient to the lead 13 of the electric double layer capacitor 10. When the lead material is Kovar, the material of the lead frame 41 is suitably 42 alloy.

  The positive electrode terminal portion 42 is formed in a U shape so as to form the upper piece 2 a and the lower piece 2 b of the positive electrode external electrode terminal 2. The negative terminal portion 43 is notched and bent in an L shape to form the fitting recess 3a and the lower piece 3b of the negative external electrode terminal 3.

  Next, the electric double layer capacitor 10 is transferred to the paired positive electrode terminal portion 42 and negative electrode terminal portion 43. Specifically, the outer lead portion 13a of the electric double layer capacitor 10 is placed on the upper piece 2a of the positive electrode terminal portion 42, and the protruding electrode 35 of the electric double layer capacitor 10 is placed on the fitting recess 3a of the negative electrode terminal portion 43. The electric double layer capacitor 10 is disposed between the positive terminal portion 42 and the negative terminal portion 43.

  When the electric double layer capacitor 10 is arranged for each pair of the positive electrode terminal portion 42 and the negative electrode terminal portion 43, the outer lead portion 13a and the protruding electrode 35 of each electric double layer capacitor 10 are connected to each corresponding pair. The terminal portions 42 and 43 are welded and fixed by laser. Thus, in each electric double layer capacitor 10, the outer lead portion 13 a is electrically connected to the positive terminal portion 42 and the protruding electrode 35 is electrically connected to the negative terminal portion 43.

  When the electric double layer capacitor 10 is completely welded to the lead frame 41, the lead frame 41 is sandwiched between upper and lower molds for resin molding and molded with resin J such as epoxy resin. Here, the resin mold conditions are such that the mold temperature is set to about 160 ° C. to 180 ° C., and the holding time in the mold is about 60 seconds to 120 seconds. Accordingly, even a unit in which the electrolytic solution 31 is filled has a sealing structure with excellent airtightness, and there is no problem even if such a resin molding step is provided. Even halogen-free and antimony-free epoxy resins can be molded at a mold temperature of about 180 ° C.

  When the resin molding is completed, the resin J is deburred and the portions of the terminal portions 42 and 43 exposed from the resin are plated. The plating is preferably lead-free plating such as Sn plating or SnBi (tin bismuth alloy) plating.

After plating, the individual elements are cut from the lead frame 41 using a die (punch and die) to take out the surface mount type electrochemical cell 1.
Then, after the electrical characteristics of the separated surface mount electrochemical cell 1 are inspected, the surface mount electrochemical cell 1 is completed.

Next, effects of the present embodiment configured as described above will be described below.
(1) According to the electric double layer capacitor 10 of the present embodiment, the base 11 having the lead 13 around which the active material 20 is wound press-fits the metal ring 14 into the cap 30 filled with the electrolytic solution 31. Thus, the electric double layer capacitor 10 was assembled. Therefore, the assembly work is very simple because it is assembled by simply press-fitting.

  Moreover, the cap 30 fits the soft metal layer 15 formed on the outer peripheral surface 14 a of the metal ring 14. Therefore, the airtightness can be made extremely higher than that of a resin gasket used conventionally. Moreover, deterioration of quality can be suppressed even in a severe environment of high temperature and humidity. Furthermore, since the resin gasket used conventionally is not used, the diameter of the cap 30 can be shortened without reducing the amount of the active material incorporated, and the electric double layer capacitor 10 can be downsized accordingly.

  (2) According to the electric double layer capacitor 10 of the present embodiment, the metal ring 14 and the lead 13 are made of Kovar (FeNiCo alloy) approximating the thermal expansion coefficient of the pellet. Accordingly, when the base 11 is formed by assembling the precursor of the pellet 12, the lead 13, and the metal ring 14 into a predetermined shape using a jig and then firing, the base 11 is not damaged due to a large difference in thermal expansion.

  (3) According to the electric double layer capacitor 10 of the present embodiment, the active material 20 wound around the lead 13 is wound from the outside so as to be tightened with an insulating tape such as polyimide resin, and then the wound active material 20 is wound. The entire outside of the substance 20 was covered with a separator sheet, or covered with an insulating film. Therefore, the active material 20 wound around the lead 13 does not short-circuit with the cap 30.

  (4) According to the electric double layer capacitor 10 of the present embodiment, since the cap 30 is formed of white and white having excellent spreadability, a covered cylindrical cap can be easily formed by deep drawing. . Moreover, since the nickel-plating excellent in corrosion resistance was plated on the surface of the white cap 30, corrosion of the cap 30 can be prevented.

  (5) According to the electric double layer capacitor 10 of the present embodiment, the surface of the inner lead portion 13b is coated with aluminum. Accordingly, it is possible to prevent the inner lead portion 13b from being corroded by the electrolytic solution 31.

(6) According to the electric double layer capacitor 10 of the present embodiment, the surface 14b of the metal ring 14 in contact with the electrolyte 31 is coated with aluminum. Accordingly, it is possible to prevent the surface 14b of the metal ring 14 in contact with the electrolytic solution 31 from being corroded by the electrolytic solution 31.
(7) According to the surface mount type electrochemical cell 1 of the present embodiment, the positive external electrode terminal 2 is electrically connected to the outer lead portion 13a by welding, and the negative external electrode terminal 3 is welded to the protruding electrode 35. Connected electrically. When the positive external electrode terminal 2 and the negative external electrode terminal 3 are resin-molded together with the electric double layer capacitor 10, a part of the resin-molded surface-mounting electrochemical cell 1 from the bottom surface 1 a of the resin J (surface with each other) The lower pieces 2b, 3b) are molded so as to be exposed.

  Therefore, when the printed circuit board P is mounted, since the lower pieces 2b and 3b which are flush with each other are connected to the wiring formed on the printed circuit board P, the surface-mounted electrochemical cell 1 is placed in a stable state. And can be mounted with high positional accuracy.

  (8) According to the surface mount electrochemical cell 1 of the present embodiment, the positive external electrode terminal 2 and the negative external electrode terminal 3 are formed by pressing and bending a single lead frame 41 on the lead frame 41. Since it is processed together, there is little variation in shape and dimensions. In addition, since the external electrode terminals 2 and 3 are embedded in the resin J, the external electrode terminals 2 and 3 are not deformed even by an externally applied force. As a result, the coplanarity is maintained until the printed circuit board P is mounted.

In addition, you may change the said embodiment as follows.
(1) In the above embodiment, the base 11 and the cap 30 are press-fitted after injecting the electrolytic solution 31 into the cap 30, but the present invention is not limited to this. A method may be used in which pores are provided on the bottom and side surfaces of the cap 30, the electrolyte solution 31 is injected after press-fitting, and then the pores are hermetically closed.

  (2) The protruding electrode 35 provided at the center of the tip of the cap 30 may be formed by processing so that the tip has a protruding shape when the cap 30 is manufactured by deep drawing. In this case, after the processing step for forming the protrusion at the tip is performed, the cap main body portion having a large diameter is continuously deep drawn.

  When a non-aqueous electrolyte battery is configured as a power generation element of an electrochemical cell, as the active material contained in the positive electrode, metal cargogenides such as TiS2, MoS2, NbSe3, MnO2, MoO3, V2O5, LixCoO2, LixNiO2, LixMn2O4, etc. Various materials capable of occluding and releasing lithium ions and anions such as metal oxides, polyaniline, polypyrrole, polyparaphenylene, polyacene, and the like, and graphite intercalation compounds can be used.

The active material contained in the negative electrode is not particularly limited, and various materials such as SiO, WO2, WO3, SnO, LiAl, Li, or a carbon material can be used.
When the electrochemical cell constitutes an electric double layer capacitor, activated carbon or activated carbon fiber can be used as the active material.

The whole perspective view of a surface mount type electrochemical cell. Sectional drawing of a surface mount type electrochemical cell. The whole perspective view which shows the external appearance of the electric double layer capacitor as an electrochemical cell. The exploded perspective view of an electric double layer capacitor. The exploded perspective view of a base. The principal part sectional drawing which shows the press-fit state of a base and a cap. Explanatory drawing for demonstrating the assembly of an active material. The figure explaining immersion of the electrolyte solution to an active material. The figure explaining the press injection to the cap of the base which wound the active material. The principal part perspective view of a lead frame.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Surface mount type electrochemical cell, 2 ... Positive electrode external electrode terminal, 3 ... Negative electrode external electrode terminal,
DESCRIPTION OF SYMBOLS 10 ... Electric double layer capacitor, 11 ... Base, 12 ... Pellet, 12a ... Through-hole, 13 ... Lead, 13a ... Outer lead part, 13b ... Inner lead part, 14 ... Ring, 15 ... Soft metal layer, 20 ... Active material , 21 ... 1st separator, 22 ... 2nd separator, 23 ... Positive electrode active material sheet, 24 ... Negative electrode active material sheet, 25 ... Connection electrode, 30 ... Cap, 30a ... Open end, 31 ... Electrolyte, 32 ... Tank 35 ... Projection electrode, J ... Resin, P ... Printed circuit board.

Claims (8)

A base having a metal lead penetrated and fixed to an insulating filler fixed in an annular metal ring having a soft metal layer formed on the outer peripheral surface;
A sheet-like electrode active material that is connected to the inner lead portion of the lead that is fixedly penetrated to the insulating filler, and the inner lead portion and the metal ring are electrically connected;
A lid-shaped cylindrical cap that is press-fitted on the outer peripheral surface of the ring so as to cover the periphery of the electrode connected to the inner lead portion of the lead, is tightly fixed to the base, and is provided with an electrode on the outer peripheral surface; ,
An electrochemical cell comprising an electrolytic solution filled in the cap. The electrochemical cell according to claim 1.
The soft metal layer formed on the outer peripheral surface of the metal ring may be a single metal of tin or silver, or tin / silver (SnAg), gold / tin (AuSn) after a copper layer or a nickel layer is formed as a base. ), A metal film made of an alloy of tin and copper (SnCu) is formed. The electrochemical cell according to claim 1 or 2,
The electrochemical cell, wherein the insulating filler fixed in the metal ring is borosilicate glass or soda glass. The electrochemical cell according to any one of claims 1 to 3,
The electrochemical cell, wherein the metal ring and the lead are made of FeNiCo alloy, iron-nickel alloy or stainless steel. The electrochemical cell according to any one of claims 1 to 4,
The electrochemical cell according to claim 1, wherein the cap is white and has a nickel (Ni) plating surface. The electrochemical cell according to any one of claims 1 to 5,
The electrochemical cell according to claim 1, wherein the inner lead portion of the lead in contact with the electrolytic solution has a surface coated with an aluminum film. The electrochemical cell according to any one of claims 1 to 6,
A portion of the ring that contacts the electrolyte solution is coated with an aluminum film. The electrochemical cell according to any one of claims 1 to 7,
A first external electrode terminal connected to an outer lead portion of the lead protruding from the base that is closely fixed to the cap;
A second external electrode terminal connected to an electrode provided on the cap that is closely fixed to the base;
A surface-mount type electrochemical cell characterized in that it is molded with resin so as to cover the closely fixed base and cap and to expose a part of the first external electrode terminal and the second external electrode terminal.

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