JP2007242548A - Method of manufacturing film-armored electric device, heater, and film-armored electric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a film-armored electric device capable of surely executing thermal adhesion in the vicinity of an electrode terminal, to provide a heater, and to provide a film-armored electric device. <P>SOLUTION: This method of manufacturing the film-armored electric device includes processes of: coating a lead terminal 4 with sealants 11 each having an extension part 11c having a surface pressingly extending a thermally-adhesive resin layer by jointing the sealants 11 to each other and pressing them; and executing thermal adhesion by using heaters 50a and 50b having a peripheral heating part 52 for thermally welding laminate films 5 and 6 in a peripheral part of a battery element 2, a lead heating part 51 for thermally welding the sealant 11 corresponding to the lead terminal 4 and formed into a recessed shape with respect to the peripheral heating part 52 to the laminate films 5 and 6, and an intermediate heating part 53 connecting the peripheral heating part 52 to the lead heating part 51 in a step-like form for thermally welding the extension part 11c of the sealant 11 to the laminate films 5 and 6. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a film-clad electrical device in which an electrical device element is accommodated in an exterior film, represented by a battery or a capacitor, a heater used for heat fusion of the film-clad electrical device, and a film-clad electrical device.

  In recent years, batteries as power sources for portable devices and the like are strongly required to be light and thin. Therefore, the battery exterior material can be further reduced in weight and thickness in place of conventional metal cans that are limited in weight and thickness, and can have a free shape compared to metal cans. As the exterior material, a metal thin film or a laminate film obtained by laminating a metal thin film and a heat-fusible resin film has been used.

  A typical example of a laminate film used as a battery exterior material is to laminate a heat-sealable resin film as a heat seal layer on one side of an aluminum thin film as a metal thin film and a protective film on the other side. Three-layer laminated film.

  In a film-clad battery using a laminate film as an exterior material, a battery element in which a positive electrode and a negative electrode are laminated via a separator is surrounded by a laminate film with a heat-fusible resin film facing each other, The battery element is hermetically sealed (hereinafter simply referred to as sealing) by heat-sealing the laminate film. In order to extract the current from the positive electrode and the negative electrode of the battery element to the outside, current collecting tabs are provided to protrude from the positive electrode and the negative electrode, respectively. These current collecting tabs are connected to lead terminals, and the lead terminals are removed from the laminate film. Protrusively connected. Moreover, as a separator, the porous film etc. which were formed using thermoplastic resins, such as polyolefin, are used.

  FIG. 5 shows a lead terminal portion of a conventional battery using a laminate film as an outer package. FIG. 6 shows a state where the lead terminal portion is heat-sealed by a conventional heater.

  The film-clad battery 100 has a configuration in which a battery element 103 is accommodated in two outer package films 101 and lead terminals 104 connected to the battery element 103 are drawn to the outside.

  The exterior body film 101 is a laminate film including a metal layer 101b and an inner surface resin layer 101a, and is bonded by thermally fusing the periphery of the inner surface resin layer 101a (the protective film is omitted in FIG. 6). ) Of these sealing sides, two opposing sides serve as lead sealing sides of the lead terminals 104, and the lead terminals 104 are drawn out from these sides. A sealant 105 made of a heat-resistant resin layer 105a and a metal adhesive resin layer 105b is provided on the surface of the lead terminal 104 made of a flat metal. The heat-resistant resin layer 105 a is intended to prevent a short circuit between the metal layer 101 b and the lead terminal 104, and the metal adhesive resin layer 105 b is intended to improve the adhesion between the lead terminal 104 and the sealant 105.

  The outline of sealing of the battery element 103 by the exterior body film 101 is as follows.

  As shown in FIG. 6, heaters 200 a and 200 b each having a recess 201 corresponding to the shape of the lead terminal sealing portion are used for heat-sealing the exterior body films 101.

First, the sealant 105 is heat-sealed to both surfaces of the portion to be sealed of the lead terminal 104 with the metal adhesive resin layer 105 b facing the lead terminal 104. With the lead terminals 104 pulled out, the lead terminals 104 are sandwiched between the edges of the upper and lower exterior body films 101, and the exterior body films 101 are heat-sealed. In the lead terminal sealing portion, the sealant 105 and the exterior body film 101 are heat-sealed.
JP 2004-111303 A

  However, when the lead terminal sealing portion including the conventional shape sealant 105 is heat-sealed by the conventional shape heaters 200a and 200b shown in FIG. 6, the following problems may occur.

As shown in FIG. 7, in the case of the conventional heaters 200 a and 200 b, there is a large step between the lead heating unit 251 and the peripheral heating unit 252. Further, in the conventional sealant 105, the end portion 105c where the sealants 105 are joined is provided with a minimum width necessary for joining. For this reason, in the combination of the conventional heaters 200 a and 200 b and the conventional sealant 105, a large space is formed at the corner C ₃ at the boundary between the lead heating unit 251 and the peripheral heating unit 252. The corner C _3, and the resin was crushed by the read heating unit 251, although crushed resin by the peripheral heating portion 252 is supplied, as the fill corners C ₃ at a desired heat Chakuhaba This resin is not supplied. Therefore, as shown in FIG. 8, which is an enlarged view of the portion A in FIG. 5, a constriction 150 narrower than the desired heat fusion width is formed in the fusion region 102 a of the exterior body film 101 at the end portion 105 c of the sealant 105. It might happen.

Since the fusion region 102a other than the vicinity of the end portion 105c of the sealant 105 is flat, a uniform pressure can be applied by the heaters 200a and 200b. As a result, the width of the resin region to be melted and integrated (hereinafter referred to as heat fusion) can be heat-sealed with the desired width a. . In contrast, the vicinity of the end portion 105c is a portion corresponding to the corner portion C ₃ to supply the resin becomes insufficient. For this reason, the constriction 150 is formed in which the width of the thermal fusion becomes a width b narrower than the width a.

  In a constriction where the width of heat fusion is narrow, it becomes a region where the amount of moisture permeated into the battery from the outside is partially increased. This is because when there is a difference in the concentration of water molecules on both sides of the resin, the amount of water molecules that permeate in the resin per unit time is inversely proportional to the length of the resin path in the permeation direction according to Fick's law. As a result, the formation of the constriction becomes an acceleration factor of moisture intrusion into the inside of the battery, leading to acceleration of deterioration of battery characteristics in which moisture has an adverse effect in the battery. This is a problem peculiar to a film-clad battery, particularly a film-clad non-electrolyte battery, and it is not just a problem that it is necessary to avoid the formation of a leak path by dividing the heat-sealed region. A landing area is required.

  Further, in mass production, since the variation of the initial thickness of the seal resin for each workpiece and the variation of the mutual positions of the heater and the workpiece are more or less inevitably caused, the resin embedding property of the seal also varies for each workpiece. Therefore, conventionally, at the design level, it has been difficult to completely prevent the formation of constriction in all manufactured products even if it is intended to satisfy a predetermined width in all fusion regions of one workpiece.

  Then, an object of this invention is to provide the manufacturing method of a film-clad electrical device, a heater, and a film-clad electrical device which can perform the heat fusion | melting of electrode terminal vicinity reliably.

In order to achieve the above object, a method for producing a film-clad electrical device of the present invention includes an electrical device element, a covering member that covers an electrode terminal connected to the electrical device element, and a heat-sealable resin layer. Film-covered electrical device having a body film, wherein the exterior device films in the periphery of the electrical device element, and the exterior device film and the covering member are heat-sealed to seal the electrical device element with the exterior body film In the manufacturing method, a step of preparing an electrode terminal on which a covering member having an extension part having a flat surface is formed, a peripheral heating part that heat-seals the exterior body films in the peripheral part of the electric device element, and Corresponding to the electrode terminals, the terminal heating part is formed in a concave shape with respect to the peripheral heating part, and the covering member and the exterior body film are heat-sealed, and the peripheral heating part and the terminal heating part are A step of preparing a heater having an intermediate heating portion that heat-bonds the extending portion of the covering member and the exterior body film connected to each other, and pressurizes the flat surface through the exterior body film by the intermediate heating portion of the heater A method of manufacturing a film-covered electrical device according to the present invention, comprising: a step of heat-sealing while stretching a heat-fusible resin layer in a region overlapping with a flat surface. The electrode terminal is covered with a member, and the extension portion is heat-pressed by a heater having an intermediate superheated portion, so that the portion of the heat-fusible resin layer corresponding to the extension portion is extruded and heat-sealed. . Thereby, the width | variety of the heat-sealed area | region in an extension part can be formed wider than the width | variety of the heat-sealed area | region in the peripheral part of an electric device element. That is, according to the present invention, it is possible to heat-bond the vicinity of the side end face of the covering member, which has been narrowed and narrowed conventionally, widely, or to prevent the occurrence of constriction even in the worst case due to manufacturing variations. Therefore, it is possible to prevent moisture from entering from the outside.

  The heater of the present invention may be made of metal. By making the heater metal, it is easy to predict the cross-sectional shape of the finished product, and it is easy to calculate the amount of resin required to fill the corners of the heater, and the simulation and actual consistency are good, so the design The street resin is stretched to fill a desired site.

  The film-clad electrical device of the present invention includes an electrical device element, a covering member that covers an electrode terminal connected to the electrical device element, and a peripheral portion of the electrical device element and a covering member that are heat-sealed to seal the electrical device element. In the film-clad electrical device having an exterior body film provided with a heat-fusible resin layer, the covering member has an extending portion having a flat surface, and the electrode terminal, the covering member, and the exterior body film A first bonding region having a first thickness including a region where the film is bonded, a second bonding region having a second thickness smaller than the first thickness, in which the exterior body films are bonded to each other, and It includes a region where the projecting portion and the exterior body film are joined, and is thinner than the first thickness and thicker than the second thickness, and is formed so as to connect the first joining region and the second joining region. A flat third bonding region And is characterized in that the heat sealing resin in the region overlapping with the flat surface of the extending portion in the third joint region is extended press.

  In the film-covered electrical device of the present invention, the width of the heat-sealed region in the extending portion may be wider than the width of the heat-sealed region in the peripheral portion of the electric device element.

  Further, in the film-clad electrical device of the present invention, the length of the extending portion in the direction extending from the electrode terminal is 1.5 mm or more and not more than the width of the heat fusion of the second bonding region. Also good.

  According to the present invention, heat sealing can be performed without causing constriction in the vicinity of the side end face of the covering member, so that moisture can be prevented from entering from the outside and the battery can have a long life.

  Next, an example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows an exploded perspective view of the film-clad battery. In addition, FIG. 1 shows the film-clad battery with the current collector protecting member of the present embodiment removed.

  The film-clad battery 1 includes a battery element 2, a positive and negative current collector 3 provided on the battery element 2, and two laminate films 5 and 6 that store the battery element 2 together with an electrolytic solution. It has an exterior body and lead terminals 4 connected to the current collector 3.

  The battery element 2 is configured by alternately laminating a plurality of positive plates and a plurality of negative plates via separators.

  Each positive plate has a positive electrode applied to an aluminum foil, a negative electrode has a negative electrode applied to a copper foil, and a current collecting tab not coated with an electrode material extending from a laminated region is a positive plate The current collecting tabs and the current collecting tabs of the negative electrode plate are collectively ultrasonically welded to form the current collecting portion 3 as a relay portion. At the same time, the lead terminal 4 is connected to the current collector 3 by ultrasonic welding.

  The exterior body is composed of two laminated films 5 and 6 that surround and surround the battery element 2 from both sides in the thickness direction. Each of the laminate films 5 and 6 is formed by laminating a heat-fusible resin layer having heat-fusibility, a metal layer, and a protective layer, and the heat-fusible resin layer made of PP (polypropylene) is a battery. The battery element 2 is sealed by heat-sealing the heat-sealing part 7 of the laminate films 5 and 6 so as to be the inner layer of the film.

  As the laminate films 5 and 6, as long as the battery element 2 can be sealed so that the electrolytic solution does not leak, a film used for this type of film-clad battery can be used. A laminate film in which a layer and a heat-fusible resin layer are laminated is used. As this type of laminate film, for example, a film obtained by attaching a heat-fusible resin having a thickness of 3 μm to 200 μm to a metal foil having a thickness of 10 μm to 100 μm can be used. As the material of the metal foil, that is, the metal layer, Al, Ti, Ti-based alloy, Fe, stainless steel, Mg-based alloy and the like can be used. As the heat-fusible resin, that is, the heat-fusible resin layer, polypropylene, polyethylene, acid-modified products thereof, polyester such as polyphenylene sulfide, polyethylene terephthalate, polyamide, ethylene-vinyl acetate copolymer, etc. can be used. . Moreover, nylon etc. are suitable as a protective layer.

  The lead terminal 4 is covered with a sealant 11 composed of a heat resistant resin layer 11a and a metal adhesive resin layer 11b. The heat-resistant resin layer 11a is intended to prevent a short circuit between the metal thin film layers of the laminate films 5 and 6 and the lead terminals 4, and has a melting point higher than that of the metal adhesive resin layer 11b or the heat-bonded resin layer of the laminate film. It is made of a resin having a high viscosity, or made of a resin cross-linked by electron beam irradiation or the like, and as the material, the same material as that used for the heat-sealed resin layer can be used. The metal adhesive resin layer 11b is intended to improve the adhesion between the lead terminal 104 and the sealant 11, and is an acid-modified product of polyolefin such as polyethylene or polypropylene, ethylene-vinyl acetate copolymer, ionomer, Polyester, acrylic resin, one-pack or two-pack adhesive, epoxy adhesive, ABS resin, and the like can be used. The sealant 11 has an extending portion 11 c that extends so as to protrude from the side end portion 4 c of the lead terminal 4. In the extending part 11c, the sealants are joined to each other.

  The sealant 11 is coated on the lead terminals 4 in advance, and then the laminate films 5 and 6 are heat-sealed. In addition, the heat sealing of the laminate films 5 and 6 where the lead terminals 4 extend was not directly heat-sealed to the lead terminals 4 but the sealant 11 was provided. The part is heat-sealed. The extension part 11c functions to extrude the heat-fusible resin layer of the laminate films 5 and 6 on the extrusion surface 11d of the extension part 11c to the outside of the extension part 11c by performing the heat fusion. To do.

  Next, FIG. 2 schematically shows the arrangement relationship of the heater, the laminate film, and the lead terminals when performing heat fusion. 2 shows the lead terminal 4 as viewed from the direction of arrow B shown in FIG. FIG. 3 is a partially enlarged view schematically showing the vicinity of the lead terminal 4 of the film-clad battery 1 in a state of being heat-pressed with a heater. FIG. 4 is a partially enlarged perspective view of the side end portion of the lead terminal.

  The laminate films 5 and 6 are sandwiched between the heaters 50a and 50b, and the lead terminals 4 covered with the sealant 11 are disposed between the laminate films 5 and 6, and the heaters 50a and 50b are shown in FIG. The laminate films 5 and 6 are heat-pressed by moving in the direction of arrow C, and the laminate films 5 and 6 are heat-sealed, and the laminate films 5 and 6 and the sealant 11 are heat-sealed.

  On the pressure surface side of the heaters 50a and 50b, the peripheral heating part 52 for heat-sealing the peripheral part of the battery element 2, the lead heating part 51 having a concave shape with respect to the peripheral heating part 52, and the lead heating part 51 and the periphery An intermediate heating unit 53 that connects the heating unit 52 in a staircase shape is formed. The heaters 50a and 50b are arranged so that the heating parts 51, 53 and 52 face each other. In the conventional heater configuration, there is no portion corresponding to the intermediate heating portion 53 or the shape is not suitable, so that the step between the portion corresponding to the lead heating portion 51 and the portion corresponding to the peripheral heating portion 52 is steep. It was the aspect which changes to. On the other hand, in this embodiment, a new flat part is provided as the intermediate heating part 53, and the step between the lead heating part 51 and the peripheral heating part 52 is changed stepwise.

The peripheral heating part 52 heat-presses the peripheral part of the battery element 2 of the laminate films 5 and 6 to form the peripheral part 52h. Peripheral portion 52h is an area in which is what laminate film 5, 6 are joined, the cross-sectional thickness of t _3. The peripheral portion 52h is heat-sealed with a width a (see FIG. 4).

The lead heating part 51 heat-presses the lead terminal 4 covered with the sealant 11 and a part of the extension part 11c to form a lead part 51h. The lead portion 51h includes a region where the lead terminal 4 and the sealant 11 and the laminate film 5, 6 are stacked, the cross-sectional thickness of t _1. More specifically, as shown in FIG. 3, the lead heating part 51 is formed wide by a distance L ₁ from the side end part 4 c of the lead terminal 4. That is, the lead heating part 51 is formed to be wide by 2L _{1 with} respect to the width of the lead terminal 4. By providing the distance L ₁ to the lead-side end surface 53a of the intermediate heating part 53, the intermediate heating part 53 applies a predetermined pressure to the extension part 11c without applying excessive pressure to the lead terminal 4 during heat press. Can do. The distance L ₁ is preferably in the range of 0.5 to 1.5 mm. If it is 0.5 mm or less, pressure may be applied to the end of the lead terminal 4 due to the movement of the mutual position of the heater and the workpiece, and the lead terminal 4 may be damaged. If it is 1.5 mm or more, it is necessary to fill the corner C _1. The resin becomes too much, and the concern about the occurrence of constriction increases, making it difficult to achieve the object of the present invention.

The intermediate heating part 53 heat-presses the part of the extension part 11c to form the intermediate flat part 53h. Intermediate flat portion 53h includes a region in which the extending portion 11c sealant 11 What happened was bonded and laminated films 5 and 6 are stacked (region of L ₃ shown in FIG. 3), in its cross-sectional thickness is t ₂ is there. The intermediate flat portion 53h has a length of L ₂ + L ₃ shown in FIG. 3, and is formed so as to connect the lead portion 51h and the peripheral portion 53h. Here, L ₃ is the distance from the lead-side end surface 53a, which is the boundary between the lead heating unit 51 and the intermediate heating unit 53, to the end surface of the extending portion 11c. L ₂ is the distance from the end face of the extending part 11 c to the peripheral side end face 53 _b that becomes the boundary between the intermediate heating part 53 and the peripheral heating part 52. Further, the intermediate heating unit 53 is configured such that the amount of crushing of the laminate films 5 and 6 is larger than the amount of crushing of the lead heating unit 51 and the peripheral heating unit 52. In other words, in the intermediate heating unit 53, the thickness A ₃ of the laminate films 5 and 6 in the intermediate heating unit 53 is changed to the thicknesses A ₁ and A ₂ of the laminate films 5 and 6 in the lead heating unit 51 and the peripheral heating unit 52. It is formed so as to be thinner in comparison.

The heat fusion part 7 formed by the heat press of the lead heating part 51, the intermediate heating part 53 and the peripheral heating part 52 includes a lead part 51h, an intermediate flat part 53h and a peripheral part 52h, and the relationship between the thicknesses of the respective parts. Has a relationship of t ₁ > t ₂ > t ₃ .

In addition, it is preferable that the length of the extension part 11c shall be 1.5 mm or more. According to the study by the present inventors, in order to reliably obtain the effect of the present invention by extending the heat-sealing resin layer by the extending portion 11c, the width of the region to be extended (the length in the lateral direction in FIG. 3). ) That is, L ₃ needs to be 1 mm or more. This is combined with the fact that the distance L ₁ from the lead side end portion 4c to the lead side end surface 53a of the intermediate heating portion 53 is considered to be a manufacturing variation, and it is preferable to secure 0.5 mm or more as described above. The length of the extending part 11c is preferably 1.5 mm or more.

On the other hand, it is preferable that the length of the extension part 11c is shorter than the width of the heat fusion region. In the region (L ₃ ) where the extending portion 11c and the intermediate flat portion 53h overlap, the resin of the inner surface resin layer is extended toward the regions on both sides, and the amount of the resin depends on each dimension. It changes as follows. In other words, when L ₃ is smaller than the width a of the heat fusion region, the left resin moves to the left and the right resin moves to the right (left and right direction in FIG. 3) from the center of L ₃ . , as L ₃ becomes longer, the resin to be extended pushing the left and right L ₃ is increased, the increase stops upon reaching the L ₃ = a that. When L ₃ > a, the amount of resin pushed to the left and right does not increase even if L ₃ becomes longer. The reason for this is that when the area to be heat-pressed is rectangular when viewed from the direction of the press axis, the amount of resin that protrudes out of the area is greater on the long side than on the short side, so if L ₃ > a, the press area increases. This is because the increased amount of resin is extruded in the front-rear direction (the direction perpendicular to the paper surface in FIG. 3), not in the left-right direction. Therefore, in the case of L ₃ > a, even if the permeation area of the resin is increased, only the demerit of increasing the water permeation is obtained.

As shown in FIG. 7, in the case of the conventional heaters 200a and 200b, there is no intermediate heating part 53 of this embodiment, so there is a large step between the lead heating part 251 and the peripheral heating part 252. Further, the conventional sealant 105 has substantially no portion corresponding to the extending portion 11c of the present embodiment. For this reason, in the combination of the conventional heaters 200 a and 200 b and the conventional sealant 105, a large space is formed at the corner C ₃ at the boundary portion between the lead heating unit 251 and the peripheral heating unit 252. The corner C _3, and the resin was crushed by the read heating unit 251, although crushed resin by the peripheral heating portion 252 is supplied to supply sufficiently the extent of resin fills the corners C ₃ Because I couldn't do it, I was constricted.

On the other hand, in this embodiment, the heaters 50 a and 50 b are provided with the intermediate heating part 53 and the sealant 11 is provided with the extending part 11 c. In the present embodiment, a combination of these forms a corner C _{1 at} the boundary between the lead heating unit 51 and the intermediate heating unit 53, and a corner at the boundary between the intermediate heating unit 53 and the peripheral heating unit 52. Part C ₂ will be formed. In the present embodiment, two corners C ₁ and C ₂ are formed, but the spatial volumes of the corners C ₁ and C ₂ are smaller than the spatial volume of the conventional corner C _3. . The intermediate heating unit 53 crushes until a thickness of A ₃ and laminate film 5, 6 parts of the extending portion 11c. Resin that has been crushed by the lead heating unit 51 and resin that has been largely crushed by the intermediate heating unit 53 flow into the corner C ₁ . In addition, the resin crushed by the peripheral heating unit 52 and the resin crushed by the intermediate heating unit 53 flow into the corner C ₂ . In other words, in the present embodiment, the space volume of the corners C ₁ and C ₂ is reduced, and a sufficient amount of resin can be supplied to these small spaces, so that the constriction occurs near the end of the sealant 11. I am trying not to. As shown in FIG. 4, the width c of the heat fusion part 7 in the portion of the extension part 11 c heat-pressed by the intermediate heating part 53 is such that the resin is extruded, so the heat fusion part 7 by the peripheral heating part 52. It is formed wider than the width a.

Note that the heaters 50a and 50b are preferably made of a metal block rather than rubber. The reason is that if the pressure is selectively and effectively applied to the portion where the resin is desired to be stretched, the flow of the resin can be realized as intended, which is convenient for controlling the filling properties of the corners C ₁ and C _2. Because. In other words, since the finished cross-sectional shape is easy to predict, it is easy to calculate the amount of resin necessary to fill the corners C ₁ and C ₂ , and the simulation and actual consistency are good. The resin can be stretched to fill the desired site. On the other hand, with a rubber heater, the surface shape changes depending on the pressure distribution, making it difficult to predict the finished cross-sectional shape, making it difficult to simulate the flow of the resin and reducing accuracy. .

  As described above, according to this embodiment, it is possible to widen the width of heat fusion by supplying sufficient resin to the heat fusion region that has been constricted in the past, thereby preventing moisture from entering from the outside. Battery life can be extended.

The step between the lead heating unit 51 and the intermediate heating unit 53 and the step between the intermediate heating unit 53 and the peripheral heating unit 52 do not have to be the same height. Further, FIG. 3 shows an example in which the shapes of the heaters 50a and 50b at the corners C ₁ and C ₂ are right angles, but the present invention is not limited to this. For example, the shape of the corner portion C ₁ of the heaters 50a and 50b may be provided with an inclined surface in combination with the slope of the sealant 11 (the portion corresponding to the corner portion C ₁ ), or may have an R shape.

  In the present embodiment, the step is increased by one step by the intermediate heating unit 53, but the step may be increased by two or more steps in order to further reduce the space volume at the corner.

In the present embodiment, the case where the amount of crushing of the intermediate heating unit 53 is larger than that of other regions has been described. However, if the occurrence of constriction can be prevented, the amount of crushing of the intermediate heating unit 53 is not necessarily limited to such a crushing amount. However, A ₁ <A ₃ <A ₂ may be satisfied (in this case, the place where the width of the fusion region is the largest is a place different from the extension portion). More specifically, the relationship between the thicknesses of the lead portion 51h, the intermediate flat portion 53h, and the peripheral portion 52h is t ₁ > t ₂ > t ₃ as described above, and the intermediate flat portion 53h and the extending portion 11c overlap each other. If so (the region of L ₃ shown in FIG. 3), the occurrence of constriction can be prevented depending on the sealing conditions, and the effect of the present invention can be obtained.

  Further, in the above-described embodiment, it has been described that the heat fusion part 7 of the intermediate flat part 53h has a width c wider than the width a of the peripheral part 52h by performing heat press with the intermediate heating part 53. However, the present invention is not limited to this, and the effect of the present invention can be obtained if the width is equal to or greater than the width a and no constriction occurs.

  In this embodiment, two sealants having a two-layer structure having a heat-resistant resin layer and a metal adhesive resin layer are used as the coating resin formed on the lead terminal, and are bonded to each other with the metal adhesive resin layer inside. However, other configurations may be used, for example, a sealant composed of only a metal-adhesive resin layer may be used, or two folded sheets may be joined without being joined, and a resin-formation scheduled part may be formed. Alternatively, a method may be used in which a lead terminal is sandwiched in a mold provided with a space, a resin is poured into a predetermined portion thereof, and the resin is coated on the lead terminal by solidification by cooling or reaction curing. Although the thickness of the extending portion is shown in FIG. 3 as being thinner than the portion overlapping the lead terminal, the same thickness may be used. In this case, when the cross section is viewed, the overall outer shape of the coating resin is rectangular.

  In the above-described embodiment, an example in which the extending portion 11c is formed at two places on both sides of the sealant 11 in FIG. 1 is shown, but the present invention is not limited to this, and the present invention is not limited to one side of the sealant 11. The case where the extending portion 11c is formed only in the case is also targeted.

It is a disassembled perspective view of an example of the film-clad battery of this invention. It is a schematic diagram which shows arrangement | positioning of the lead terminal provided with the heater of this invention, a laminate film, and the sealant of this invention. FIG. 4 is a partially enlarged view schematically showing the vicinity of a lead terminal in a state where heat pressing is performed with the heater of the present invention. It is a partially expanded perspective view of the side end portion of the lead terminal in the battery of the present invention. It is a figure which shows an example of the lead terminal part of the conventional battery which used the laminate film as an exterior body. It is a schematic diagram which shows arrangement | positioning of the lead terminal provided with the conventional heater, the laminate film, and the conventional sealant. It is a partial enlarged view which shows typically the lead terminal vicinity of the state heat-pressed with the conventional heater. It is a partially expanded perspective view of a side end portion of a lead terminal in a conventional battery.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Film exterior battery 2 Battery element 3 Current collection part 4 Lead terminal 4c Side edge part 5 Laminated film 7 Heat-fusion part 11 Sealant 11a Heat resistant resin layer 11b Metal-adhesive resin layer 11c Extension part 11d Extrusion surface 50a Heater 51 Lead Heating part 51h Lead part 52 Peripheral heating part 52h Peripheral part 53 Intermediate heating part 53a Lead side end face 53b Peripheral side end face 53h Intermediate flat part

Claims (5)

The exterior body having an electrical device element, a covering member that covers an electrode terminal connected to the electrical device element, and an exterior body film provided with a heat-fusible resin layer, the peripheral body of the peripheral portion of the electrical device element In the method for producing a film-covered electrical device in which the electrical device elements are sealed with the exterior body film by thermally fusing the films, and the exterior body film and the covering member,
Preparing the electrode terminal on which the covering member having an extending portion having a flat surface is formed;
Peripheral heating part for heat-sealing the exterior body films in the peripheral part of the electrical device element, and the covering member and the exterior body film corresponding to the electrode terminal and having a concave shape with respect to the peripheral heating part A terminal heating unit that thermally bonds the peripheral heating unit and the terminal heating unit in a step-like manner, and an intermediate heating unit that thermally bonds the extension portion of the covering member and the exterior body film. Preparing a heater having:
The intermediate heating part of the heater presses the flat surface through the exterior body film, thereby heat-sealing while stretching the heat-fusible resin layer in a region overlapping the flat surface. A method for producing a film-clad electrical device, comprising:   The method for manufacturing a film-covered electrical device according to claim 1, wherein the heater is made of metal. An electric device element, a covering member that covers an electrode terminal connected to the electric device element, and a thermal fusion that seals the electric device element by heat-sealing a peripheral portion of the electric device element and the covering member In a film-covered electrical device having an exterior body film provided with a conductive resin layer,
The covering member includes an extending portion having a flat surface,
A first bonding region having a first thickness including a region where the electrode terminal, the covering member, and the exterior body film are bonded;
A second bonding region having a second thickness smaller than the first thickness, wherein the exterior body films are bonded to each other;
Including a region where the extension part and the exterior body film are bonded, and is thinner than the first thickness and thicker than the second thickness, and the first bonding region and the second bonding region, And a flat third bonding region formed so as to connect the two,
The film-covered electrical device, wherein a heat-sealing resin in a region overlapping with the flat surface of the extension portion is extended in the third bonding region.   The film-clad electrical device according to claim 3, wherein a width of the heat-sealed region in the extension portion is wider than a width of the heat-sealed region in the peripheral portion of the electric device element.   5. The length of the extending portion in a direction extending from the electrode terminal is 1.5 mm or more and not more than a width of heat fusion of the second bonding region. 6. Film exterior electrical device.

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