JP2008016368A - Film armored battery and battery pack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily, surely connect and disconnect a plurality of film armored batteries. <P>SOLUTION: The film armored battery keeps the inside of an armor film in which an electrode group is housed in a pressure reduction state, and is equipped with a positive electrode conductive plate arranged between the electrode group and the armor film and electrically connected to a positive electrode of the electrode group; a negative electrode conductive plate arranged between the electrode group and the armor film and electrically connected to a negative electrode of the electrode group; a positive electrode connection terminal arranged in a position overlaping on the electrode group on the positive electrode conductive plate; and a negative electrode connection terminal arranged in a position overlaping on the electrode group on the negative electrode conductive plate, and at least one of the positive/negative electrode connection terminals passes through the armor film and projects to the outside. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a film-clad battery in which a battery element is accommodated in an exterior film.

  2. Description of the Related Art Today, a battery in which a battery element in which a positive electrode plate and a negative electrode plate are wound or alternately stacked via a separator is surrounded by an outer package together with an electrolyte is used as a power source for portable devices and electric vehicles. However, in this type of battery, individual outputs are not so large, and a usage form in which a necessary output is obtained by connecting a plurality of batteries in series is common. In the following description, individual batteries connected in series are referred to as “unit cells”, and a battery in which a plurality of unit cells are electrically connected is referred to as an “assembled battery” or an “assembled battery”.

  As a technique for electrically connecting the cells, Patent Document 1 discloses the following technique. That is, two or more unit cells are inserted by inserting the convex part of the convex terminal penetrating the side wall of the battery case of one unit cell into the concave part of the concave terminal penetrating the side wall of the battery case of the other unit cell. A technique for connecting the devices in series is disclosed.

In Patent Document 2, a basic cell in which a positive electrode layer and a negative electrode layer are laminated via a separator is disposed between a pair of metal terminal plates, and the metal terminal plate and the basic cells are packaged with a laminate film. At the same time, it is disclosed that a part of the metal terminal plate is exposed from a window provided in the laminate film, and the exposed surface of the metal terminal plate is used as an external connection terminal.
JP 2001-126706 A JP 2003-123832 A

  However, when the unit cell constituting the assembled battery is a film-clad battery, there is the following problem in applying the conventional technique disclosed in Patent Document 1. That is, the single battery disclosed in Patent Document 1 is a prismatic storage battery in which an electrode group and an electrolytic solution are housed in a container made of a resin battery case and a lid. That is, the exterior (battery) of each unit cell itself has sufficient rigidity. Therefore, as shown in FIG. 1 and FIG. 5 of Patent Document 1, even if a convex terminal or a concave terminal is provided through the side wall of the battery case hollow portion not facing the accommodated electrode group. These terminals are firmly held by the battery case side wall and can be inserted and removed.

  However, in the case of a film exterior battery, the exterior is an aluminum laminate film or other flexible film. Therefore, even if a terminal penetrating the exterior is provided, it is difficult to hold the terminal using the rigidity of the exterior. In addition, when the terminals are inserted and removed, the exterior film is deformed, and if the deformation exceeds the limit, there is a possibility that a crack or the like may occur.

  On the other hand, the prior art disclosed in Patent Document 2 exposes a part of a metal terminal plate from a window provided in a laminate film, and uses the exposed surface as an external connection terminal. And the metal terminal board is laminated | stacked on the basic cell, and is not necessarily held by the laminate film. Therefore, it is thought that the problem like the prior art currently disclosed by the said patent document 1 does not generate | occur | produce.

  However, the prior art disclosed in Patent Document 2 has another problem as follows. That is, when a plurality of laminate film-covered electricity storage devices (unit cells) disclosed in Patent Document 2 are arranged to form an assembled battery, adjacent unit cells are in close contact with each other and cooling performance is inferior. Further, it becomes impossible to forcibly cool the assembled battery by supplying cooling air between the single cells. In order to avoid such a problem, it is necessary to interpose a separate spacer between adjacent unit cells, which causes inconveniences such as an increase in the number of parts and an increase in the assembly process.

  An object of the present invention is to provide a single battery and an assembled battery that can solve at least one of the above problems.

  The film-clad battery of the present invention is a film-clad battery in which the inside of the exterior film in which the electrode group is accommodated is maintained in a reduced pressure state, and is disposed between the electrode group and the exterior film, and the positive electrode of the electrode group A positive electrode conductive plate electrically connected to the negative electrode conductive plate disposed between the electrode group and the exterior film and electrically connected to a negative electrode of the electrode group; and on the positive electrode conductive plate. And a positive electrode connection terminal disposed at a position overlapping with the electrode group, and a negative electrode connection terminal disposed on the negative electrode conductive plate and disposed at a position overlapping with the electrode group. At least one of the terminal and the negative electrode connection terminal protrudes outside through the exterior film.

  The electrode group includes a plurality of electrode plates stacked via separators, and the positive electrode conductive plate is parallel to the electrode plate between the electrode plate at one end in the stacking direction and the inner surface of the exterior film facing the electrode plate. The negative electrode conductive plate is preferably disposed in parallel with the electrode plate between the electrode plate at the other end in the laminating direction and the inner surface of the exterior film facing the electrode plate.

  One assembled battery of the present invention includes a plurality of film-covered batteries of the present invention having the above-described features arranged adjacent to each other, and one of the adjacent film-covered batteries has a positive electrode connection terminal or a negative electrode connection terminal, and the other has a negative electrode It is connected to a connection terminal or a positive electrode connection terminal, and a clearance is formed between adjacent film-clad batteries by the connected positive / negative electrode connection terminals.

  Another one of the assembled batteries of the present invention includes an electrode group, a positive electrode conductive plate electrically connected to the positive electrode of the electrode group, a negative electrode conductive plate electrically connected to the negative electrode of the electrode group, A plurality of film-clad batteries in which a part of the positive / negative electrode conductive plate is exposed to the outside are disposed adjacent to each other, and the adjacent film-clad The batteries are disposed between the exposed surface of the positive electrode conductive plate or the negative electrode conductive plate provided in one film-covered battery and the exposed surface of the negative electrode conductive plate or the positive electrode conductive plate provided in the other film-covered battery. The conductors are connected via a conductor, and the conductor is disposed in a recess formed in at least one of the two exposed surfaces. In this case, it is preferable that a clearance is formed between the adjacent film-clad batteries by the conductor. Moreover, it is preferable that a plurality of the recesses are formed in a lattice shape, and the conductor is disposed in each recess.

  According to the present invention, a plurality of film-clad batteries can be easily and reliably connected / disconnected. Furthermore, a predetermined clearance can be formed between the connected film-clad batteries without using a separate member such as a spacer.

(Embodiment 1)
Hereinafter, an example of the embodiment of the film-clad battery of the present invention will be described. In the film-clad battery of this example, the battery element is surrounded by the exterior film.

  FIG. 1 is a schematic cross-sectional view showing a schematic structure of a film-clad battery 1A of this example. 1 A of film-clad batteries of this example are the battery element 2, the exterior film 3 which accommodates the battery element 2 with electrolyte solution not shown, the positive electrode electrically conductive board 4a laminated | stacked on one main surface of the battery element 2, and the other The exterior film 3 is made up of two laminated films 5 and 6.

  The two laminated films 5 and 6 constituting the exterior film 3 are composed of three layers of a heat-sealing layer, a metal layer, and a protective layer. In this example, the heat fusion layer is formed of PP (polypropylene), the metal layer is formed of aluminum, and the protective layer is formed of nylon or PET (polyethylene terephthalate). Both laminate films 5 and 6 surround the positive and negative electrode conductive plates 4a and 4b and the battery element 2 inside thereof in such a direction that the heat-sealing layer is inside, and the peripheral edges of the opposing heat-sealing layers are airtight. It is heat-sealed. Further, the inside of the laminate films 5 and 6 (inside the exterior film 3) is decompressed to a substantially vacuum state.

  The battery element 2 includes a separator 10 and a plurality of positive plates 11 and negative plates 12 that are alternately stacked via the separator 10. More specifically, each positive electrode plate 11 is obtained by applying a positive electrode material to a substantially rectangular aluminum foil, and each negative electrode plate 12 is obtained by applying a negative electrode material to a substantially rectangular copper foil. An uncoated portion to which no electrode material is applied is provided on both outer sides in the longitudinal direction of the respective foils, and the uncoated portion extends to the outside of the laminated region, and the positive / negative electrode extending portion 11a. , 12a are formed. In other words, a plurality of positive electrode extending portions 11a are drawn from one short side of the battery element 2, and a plurality of negative electrode extending portions 12a are drawn from the other short side. Furthermore, each positive electrode extension part 11a is ultrasonically welded to the positive electrode conductive plate 4a, and each negative electrode extension part 12a is ultrasonically welded to the negative electrode conductive plate 4b.

  Further, the pair of positive electrode conductive plate 4a and negative electrode conductive plate 4b are arranged so as to sandwich the battery element 2 from both sides of the electrode plate in the stacking direction. That is, the positive electrode conductive plate 4 a faces the outermost positive electrode plate 11, and the negative electrode conductive plate 4 b faces the outermost negative electrode plate 12. Further, one side of the positive / negative electrode conductive plates 4a, 4b is bent toward the other conductive plate 4b, 4a, and the positive / negative electrode extending portions 11a, 12a are welded to the inner surfaces of the bent portions, respectively. When the outermost layers on both sides of the battery element 2 are negative electrodes, it is necessary to provide an insulator such as a resin sheet between the battery element 2 and the positive electrode conductive plate 4a. The same applies to the opposite pole.

  Here, as described above, the inside of the exterior film 3 is decompressed to a substantially vacuum state. In the drawing, the exterior film 3 and the positive / negative electrode conductive plates 4a and 4b are drawn so as to be separated from each other, but since the inside is decompressed, the outer film 3 is actually a positive / negative electrode conductive plate. 4a and 4b are in close contact. Therefore, the positive / negative electrode conductive plates 4 a and 4 b laminated on the main surface of the battery element 2 are strongly pressed in a direction to be pressed against the battery element 2 directly by atmospheric pressure or through the exterior film 3. Thereby, the separator 10, the positive electrode plate 11, and the negative electrode plate 12 which comprise the battery element 2 are also pressed strongly toward the lamination direction inner side. As a result, the positive / negative electrode conductive plates 4a and 4b, the separator, and the positive / negative electrode plates 11 and 12 are strongly fixed and substantially integrated. Furthermore, each of the positive / negative electrode plates 11 and 12 is only a thin metal foil, but a plurality of positive / negative electrode plates 11 and 12 are laminated and pressed strongly toward the inner side in the lamination direction by atmospheric pressure. As a result, sufficient rigidity that does not easily bend and deform as a whole has been achieved. This is one of the major features of a film-clad battery in which the exterior is made of a flexible film and the inside is maintained in a reduced pressure state.

  On the surface of the positive electrode conductive plate 4a, the positive electrode connection terminal 20a is provided in an electrically conductive and mechanically fixed manner. This positive electrode connection terminal 20a is provided on the positive electrode conductive plate 4a and in an area overlapping with the separator 10 and the positive / negative electrode plates 11 and 12, and is formed in the exterior film 3 (aluminum laminate film 5). It protrudes to the outside through the part 13. On the other hand, on the surface of the negative electrode conductive plate 4b, a negative electrode connection terminal 20b into which the positive electrode connection terminal 20a can be inserted and removed is electrically connected and mechanically fixed. This negative electrode connection terminal 20b is also provided on the negative electrode conductive plate 4b and is projected in a region overlapping with the separator 10 and the positive / negative electrode plates 11 and 12, and is formed in the exterior film 3 (aluminum laminate film 6). It protrudes to the outside through the part 13.

  Examples of a method for fixing the positive / negative electrode conductive plates 4a, 4b and the positive / negative electrode connection terminals 20a, 20b include screwing, welding, fitting, and the like, among which welding is preferable. However, the positive / negative electrode conductive plates 4a, 4b and the positive / negative electrode connection terminals 20a, 20b can be integrally formed.

  Here, regardless of the fixing method between the positive / negative electrode conductive plates 4a, 4b and the positive / negative electrode connection terminals 20a, 20b, the conductive plates 4a, 4b and the outer film 3 A sealing material 13a bonded to each other is provided, thereby separating a space and maintaining airtightness inside and outside the battery.

  As described above, in the film-clad battery 1 </ b> A of this example, the pair of connection terminals protrudes from the region overlapping the main surface of the battery element 2. As described above, the battery element 2 has sufficient rigidity as a whole, and the positive / negative electrode connection terminals 20a protruding from the positive / negative electrode conductive plates 4a, 4b that are integrated with the battery element 2, 20b is equivalent to projecting on a solid foundation. Therefore, the force in the direction of pushing the positive / negative electrode connection terminals 20a, 20b is supported by the rigidity of the battery element 2, and the force in the direction of pulling out the positive / negative electrode connection terminals 20a, 20b is applied to the positive / negative electrode conductive plates 4a, 4b. Since the atmospheric pressure counters this, the positive / negative electrode conductive plates 4a, 4b and the battery element 2 are not separated. An adhesive layer or an adhesive layer may be provided between the positive / negative electrode conductive plates 4a, 4b and the battery element 2, but even without these, only the pressing force by atmospheric pressure is sufficient as described above. .

  Here, the state which inserted the positive electrode connection terminal 20a with which the same film-clad battery 1B is equipped in the negative electrode connection terminal 20b with which the film-clad battery 1A shown in FIG. 1 is equipped is shown in FIG. As shown in the drawing, by connecting both terminals 20a and 20b, the film-clad batteries 1A and 1B are electrically and mechanically connected, and the assembled battery of the present invention is configured. Furthermore, if the inner diameter dimension of the negative electrode connection terminal 20b is the same as or slightly smaller than the outer diameter dimension of the positive electrode connection terminal 20a, and the positive electrode connection terminal 20a is press-fitted into the negative electrode connection terminal 20b, the terminals can be connected to each other. It can also be prevented from being inadvertently released. In any case, the positive / negative electrode connection terminals 20a and 20b are firmly held by the solid base as described above, and there is no occurrence of displacement or deformation due to the stress generated during insertion and removal. . Further, the positive / negative electrode conductive plates 4a, 4b are not separated from the battery element 2, and the terminal installation portion is not deformed outward, and the battery outer shape is not deformed.

  Further, as is apparent from FIG. 2, when the positive electrode connection terminal 20a of one film-clad battery 1B is inserted into the negative electrode connection terminal 20b of the other film-clad battery 1A, both batteries are connected by the positive / negative electrode connection terminals 20a and 20b. A predetermined clearance (gap) is formed between 1A and 1B. In other words, both the height and / or the depth of the positive / negative electrode connection terminals 20a, 20b are defined so that a predetermined gap is formed between the connected film-clad batteries 1A, 1B. With such a configuration, when a plurality of film-clad batteries are arranged adjacent to each other and electrically connected to each other, a gap is formed between the adjacent batteries, and the cooling performance is improved. Further, if necessary, cooling air can be supplied to the gap to perform forced cooling.

  As described above, the positive / negative electrode connection terminals 20a and 20b form a gap between the role of electrically connecting adjacent film-covered batteries, the role of mechanically connecting, and the connected film-covered batteries. It can be understood that the three roles are the role of the spacer.

  Up to this point, an example of an embodiment of the present invention has been described by taking as an example a film-clad battery in which one positive and one negative connection terminal is provided. However, it is obvious that the positive and negative electrode connection terminals are firmly held by the above principle as long as they are provided in a region overlapping the main surface of the battery element. Therefore, for example, as shown in FIG. 3, it is also possible to provide a plurality of positive / negative electrode connection terminals 20a and 20b in one film-covered battery 1A (although the negative electrode connection terminal 20b is not shown in FIG. 3). Of course, a negative electrode connection terminal 20b corresponding to the illustrated positive electrode connection terminal 20a is provided). Further, when a plurality of positive / negative electrode connection terminals are provided, it is only necessary that the corresponding terminals can be inserted and removed, and it is not necessary to make the shapes and dimensions of all the terminals the same. For example, as shown in FIG. 4, larger positive / negative electrode connection terminals 20a and 20b than the others can be provided at the center of the film-clad battery 1A shown in FIG. 3 (the illustration of the negative electrode connection terminal 20b is also omitted in FIG. 4). To do).

Moreover, the external shape of the positive / negative electrode connection terminal is not limited to a columnar shape or a cylindrical shape. 5A to 5C show examples of variations of the positive / negative electrode connection terminals. The positive electrode connection terminal 21a shown in FIG. 5 (a) is obtained by forming a spherical locking portion 31 at the tip of a rod-like base body 30 protruding from the positive electrode conductive plate 4a. On the other hand, the negative electrode connection terminal 21 b protrudes from the negative electrode conductive plate 4 b, has moderate elasticity, and has an opening 32 having a slightly smaller diameter than the locking portion 31. Therefore, when the locking part 31 is pushed into the opening part 32, the diameter of the opening part 32 slightly increases due to elastic deformation, and the locking part 31 fits inside the negative electrode connection terminal 21b. Thereby, the positive electrode connection terminal 21a and the negative electrode connection terminal 21b are electrically and mechanically connected. Moreover, after the latching | locking part 31 fits, the diameter of the opening part 32 is restored to the original magnitude | size, and the careless removal of the latching | locking part 31 is controlled. Here, the total length (H ₁ ) of the positive electrode connection terminal 21b is longer than the depth (D ₁ ) of the negative electrode connection terminal 21b, and the locking portion 31 contacts the bottom surface (negative electrode conductive plate 4b) of the negative electrode connection terminal 21b. In this state, a gap is formed between the film-clad batteries connected by the positive / negative electrode connection terminals 21a and 21b. The size of the gap can be adjusted by changing the total length (H ₁ ) of the positive electrode connection terminal 21b or the depth (D ₁ ) of the negative electrode connection terminal 21b. In FIG. 5A, illustration of the exterior film is omitted, and the positive and negative electrode conductive plates 4a and 4b are depicted as being exposed, but are actually covered with the exterior film.

The positive electrode connection terminal 22a shown in FIG. 5B is a wire having one end connected to the positive electrode conductive plate 4a and the other end folded back to the positive electrode conductive plate 4a side. On the other hand, the negative electrode connection terminal 22b is a loop-shaped wire connected to the negative electrode conductive plate 4b. Accordingly, the terminals 22a and 22b are electrically and mechanically connected by hooking the folded portion 40 of the positive electrode connection terminal 22a to the negative electrode connection terminal 22b. The total length (H ₂ ) of the positive electrode connection terminal 21b is connected by the positive / negative electrode connection terminals 21a and 21b with the apex 41 of the folded portion 40 hooked to the negative electrode connection terminal 22b in contact with the negative electrode conductive plate 4b. The length is such that a gap is formed between the film-clad batteries. The gap can be adjusted by changing the total length (H ₂ ) of the positive electrode connection terminal 21b. In addition, the point which illustration of the exterior film is abbreviate | omitted is the same as that of Fig.5 (a). The positive / negative electrode connection terminals 22a and 22b made of the folded wire and the loop wire are preferably as small and large as possible. It is preferable to provide one or more per 1.0 mm ² . Thereby, not only the mechanical fixability per unit area is improved, but also the conductivity between terminals is improved.

  The positive electrode connection terminal 23a shown in FIG. 5 (c) has a wedge shape that tapers from the base side to the front end side that are connected to the positive electrode conductive plate 4a. On the other hand, the negative electrode connection terminal 23b has a cylindrical shape provided with an insertion port 50 capable of receiving the positive electrode connection terminal 23a. Therefore, by inserting the positive electrode connection terminal 23a inside the negative electrode connection terminal 23b, both the terminals 23a and 23b are electrically and mechanically connected. Here, the outer diameter at a position closer to the root by a predetermined distance from the tip of the positive electrode connection terminal 23a is thicker than the inner diameter of the insertion port 50 of the negative electrode connection terminal 23b, and the positive electrode to the negative electrode connection terminal 23b depends on the position of the larger diameter portion. The insertion length of the connection terminal 23a is defined. Therefore, when the positive electrode connection terminal 23a is inserted into the negative electrode connection terminal 23b to a predetermined position, a gap is formed between the film-clad batteries connected by the positive and negative electrode connection terminals 23a and 23b. Further, the size of the gap can be adjusted by changing the position of the large diameter portion in the positive electrode connection terminal 23a or the inner diameter of the negative electrode connection terminal 23b. In addition, the point which illustration of the exterior film is abbreviate | omitted is the same as that of Fig.5 (a).

  As mentioned above, although the example of the variation of a positive electrode connection terminal and a negative electrode connection terminal was demonstrated, it is self-evident that the relationship between a positive electrode connection terminal and a negative electrode connection terminal can be reversed. For example, the positive electrode connection terminals 21a to 23a shown in FIGS. 5A to 5C can be used as the negative electrode connection terminals 21b to 23b, and the negative electrode connection terminals 21b to 23b can be used as the positive electrode connection terminals 21a to 23a. .

  In addition, as described above, when connecting the batteries with the positive and negative electrode connection terminals, it is also preferable to obtain more reliable conductivity by performing soldering, laser welding, resistance welding, etc. instead of simple contact or clamping. . The current used for resistance welding may be taken from the battery itself. Further, a gasket may be used or the resin may be molded so that the connection portion becomes airtight. The metal used for the positive / negative electrode connection terminal may be the same as or different from the conductive plate. However, when the metal of the connection terminal is different between the positive electrode side and the negative electrode side, the resin mold is preferably applied. On the other hand, when the metal of the connection terminal is the same on the positive electrode side and the negative electrode side, the conductive plate and the terminal are inevitably different metals on at least one of the electrodes. In such a case, for example, as shown in FIG. 6A, the boundary portion between the positive / negative electrode connecting terminal 20a (20b) and the positive / negative electrode conductive plate 4a (4b) may be covered with a sealing material 13a. preferable. This is because if the dew condensation water from the outside air adheres to the interface of the different metal or the electrolyte inside the battery comes into contact, corrosion by the local battery may occur.

If there is no concern about the corrosion problem as described above, for example, the configuration shown in FIG. The configuration shown in the figure is such that a base portion 20c (20d) is provided on the positive / negative electrode connection terminal 20a (20b), and a sealing material 13a is interposed between the base portion 20c (20d) and the exterior film 3. is there.
(Embodiment 2)
Hereinafter, other examples of the embodiment of the assembled battery of the present invention will be described. The basic configuration of the unit cell constituting the assembled battery of this example is the same as the film-clad battery described in the first embodiment. The difference is that, as shown in FIG. 6 (a), a plurality of concave portions 60 are formed in a lattice shape (array shape) in a part of the positive electrode conductive plate 4a and the negative electrode conductive plate 4b exposed from the exterior film (not shown). It is a point that has been. In the assembled battery of this example constituted by the film-clad battery having such a feature, the positive electrode conductive plate 4a of one film-clad battery 1C and the negative electrode conductive plate 4b of the other film-clad battery 1D opposite to this are spherical. Electrical connection is made via solder (ball grid). More specifically, as shown in FIG. 6 (b), each recess 60 formed on the exposed surface of the positive electrode conductive plate 4a and each formed on the exposed surface of the negative electrode conductive plate 4b opposed thereto. The positive and negative electrode conductive plates 4a and 4b are electrically connected to each other by forming and positioning a ball grid 61 between the concave portions 60. Here, the relationship between the depth of the recess 60 and the diameter of the ball grid 61 is defined by a dimension in which a predetermined gap is formed between the film-clad batteries 1C and 1D to be connected.

  However, from the viewpoint of positioning of the ball grid 61, it is sufficient that the concave portion 60 is formed on either the exposed surface of the positive electrode conductive plate 4a or the exposed surface of the negative electrode conductive plate 4b to be connected. There is no need to form. That is, when viewed as a single film-clad battery, it is only necessary that a concave portion is formed on either the positive electrode conductive plate or the negative electrode conductive plate provided in the battery.

  In the case of this example as well, it is preferable to obtain more reliable conductivity by performing soldering, laser welding, resistance welding or the like when connecting the batteries with the connection terminals. Moreover, you may take out the electric current used for resistance welding from battery itself. Further, a gasket may be used or the resin may be molded so that the connection portion is airtight. The metal used for the connection terminal may be the same as or different from the conductive plate. However, when the metal of the connection terminal is different between the positive electrode side and the negative electrode side, it is preferable to apply the resin mold. In addition, when the metal of the connection terminal is the same on the positive electrode side and the negative electrode side, it is preferable to cover the boundary portion between the connection terminal and the conductive plate with a sealing material as in the first embodiment.

  As mentioned above, although typical embodiment of this invention was described, it supplements about the structure of each part of a film-clad battery below.

(Exterior film)
The exterior film is not particularly limited as long as the battery element can be covered so that the electrolyte solution does not leak and has flexibility, but a metal layer and a heat fusion layer are laminated. A laminate film is particularly preferably used. As this type of laminate film, for example, a film obtained by forming a heat-sealing layer having a thickness of 3 μm to 200 μm on a metal foil having a thickness of 10 μm to 100 μm can be used. As the material of the metal foil, Al, Ti, Ti-based alloy, Fe, stainless steel, Mg-based alloy and the like can be used. As the material for the heat-sealing layer, polypropylene, polyethylene, these acid-modified products, polyphenylene sulfide, polyesters such as polyethylene terephthalate, polyamide, ethylene-vinyl acetate copolymer, and the like can be used. As the material for the protective layer, polyamide such as nylon, polyester such as PET, polyethylene naphthalate (PEN), polypropylene, and the like can be used.

(Battery element)
The positive electrode plate is not particularly limited as long as it absorbs positive ions or releases negative ions during discharge, and (i) a metal oxide such as LiMnO ₂ , LiMn ₂ O ₄ , LiCoO ₂ , LiNiO ₂ , ( ii) Conventionally known materials can be used as positive electrode materials for secondary batteries such as conductive polymers such as polyacetylene and polyaniline. Further, a positive electrode active material (not shown) can be mixed with an appropriate binder or functional material on the positive electrode plate. Examples of these binders include halogen-containing polymers such as polyvinylidene fluoride, and functional materials include conductive polymers such as acetylene black, polypyrrole, and polyaniline for ensuring electron conductivity, ion conductivity. For example, a polymer electrolyte, a complex thereof, and the like.

  The negative electrode plate is not particularly limited as long as it is a material capable of occluding and releasing cations. Natural graphite, crystalline carbon such as graphitized carbon obtained by heat treatment of coal / petroleum pitch at high temperature, coal, petroleum pitch coke Conventionally known negative electrode active materials for secondary batteries such as amorphous carbon obtained by heat treatment of acetylene pitch coke and the like, lithium alloys such as metallic lithium and AlLi can be used.

Examples of the electrolyte solution impregnated in the battery element include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, γ-butyrolactone, N, N′-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, m - a cresol, a highly basic solvent of available polar as an electrolyte of a secondary battery, Li or K, an alkali metal cation and ClO such as Na _{^{4 -, BF 4 -, PF}} 6 -, CF 3 SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , (C ₂ F ₅ SO ₂ ) ₃ C ^{− and the} like What melt | dissolved the salt which consists of the anion of the compound to contain is mentioned. Moreover, the solvent and electrolyte salt which consist of these basic solvents can also be used individually or in combination. Moreover, it is good also as a gel electrolyte made into the polymer gel containing electrolyte solution. Further, a solid electrolyte or a polymer electrolyte may be used.

  The above is a material system as a lithium ion secondary battery, but the present invention can also be applied to a lead battery, a nickel cadmium battery, and a nickel metal hydride battery. Furthermore, the present invention is also applicable to an electric device in which an electric device element such as a capacitor element exemplified by a capacitor such as an electric double layer capacitor or an electrolytic capacitor is sealed with an exterior film.

(Positive electrode conductive plate)
The positive electrode conductive plate is preferably a metal species that can be electrochemically used as the positive electrode side, and has a rigidity that can withstand the stress when the connection terminal is pulled. However, if it is too thick, space is wasted. Therefore, an Al plate having a thickness of 0.1 mm to 3.0 mm is preferable. Moreover, in order to improve the adhesiveness with the sealing material, it is preferable to perform a surface shape complicated treatment such as a roughening treatment or a corrosion-resistant coating surface treatment such as a chromate treatment. In addition to Al, Ti, Mg, and alloys thereof may be used.

(Negative electrode plate)
The negative electrode conductive plate is preferably a metal species that can be electrochemically used on the negative electrode side, and has a rigidity that can withstand the stress when the connection terminal is pulled. However, if it is too thick, space is wasted. Therefore, a Cu plate or Ni plate having a thickness of 0.1 mm to 3.0 mm is preferable. Moreover, in order to improve the adhesiveness with the sealing material, it is preferable to perform a surface shape complicated treatment such as a roughening treatment or a corrosion-resistant coating surface treatment such as a chromate treatment. In addition to Cu and Ni, iron, stainless steel, alloys thereof, or the like may be used, or a Cu and Ni clad material or Ni plated Cu may be used.

(Seal material)
It is necessary to select a sealing material that adheres to both the heat-sealing layer of the exterior film and the metal, and is selected from the group consisting of epoxy adhesive, acid-modified polypropylene, ionomer, polyester, and ethylene-vinyl acetate polymer. Are illustrated. These crosslinked bodies may be used, and a laminate of a crosslinked body and a non-crosslinked body may be used.

  So far, the embodiment of the present invention has been described by taking the case where the battery element is a laminated type as an example, but the battery element may be a wound type.

It is sectional drawing which shows an example of embodiment of the film-clad battery of this invention. FIG. 4 is a partially omitted cross-sectional view showing a connection state between a positive electrode connection terminal and a negative electrode connection terminal. It is a perspective view which shows an example of a positive / negative electrode connection terminal. It is a perspective view which shows the other example of a positive / negative electrode connection terminal. It is a fragmentary sectional view which shows the other example of the positive / negative electrode connection terminal. It is a fragmentary sectional view which shows an example of the seal structure in the opening part of an exterior film. It is a fragmentary sectional view which shows an example of the connection structure of the cell in the assembled battery of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1A, 1B, 1C, 1D Film exterior battery 2 Battery element 3 Exterior film 4a, 4b Positive / negative electrode conductive plate 5, 6 Laminate film 10 Separator 11 Positive electrode body 11a, 12a Positive / negative electrode extension part 12 Negative electrode plate 13 Opening part 13a Sealing material 20a to 23a Positive electrode connection terminal 20b to 23b Negative electrode connection terminal 30 Base 31 Locking portion 32 Opening portion 40 Folding portion 41 Vertex 50 Insertion port 60 Recess 61 Ball grid

Claims (6)

A film exterior battery in which the inside of the exterior film containing the electrode group is maintained in a reduced pressure state,
A positive electrode conductive plate disposed between the electrode group and the exterior film and electrically connected to a positive electrode of the electrode group;
A negative electrode conductive plate disposed between the electrode group and the exterior film and electrically connected to a negative electrode of the electrode group;
A positive electrode connection terminal disposed on the positive electrode conductive plate and at a position overlapping with the electrode group;
A negative electrode connection terminal on the negative electrode conductive plate and disposed at a position overlapping with the electrode group,
At least one of the positive electrode connecting terminal and the negative electrode connecting terminal penetrates the outer film and protrudes to the outside.   The electrode group includes a plurality of electrode plates stacked via separators, and the positive electrode conductive plate is parallel to the electrode plate between the electrode plate at one end in the stacking direction and the inner surface of the exterior film facing the electrode plate. The negative electrode conductive plate is arranged in parallel with the electrode plate between the electrode plate at the other end in the laminating direction and the inner surface of the exterior film facing the electrode plate. Film outer battery.   A plurality of film-clad batteries according to claim 1 or 2 are arranged adjacent to each other, and a positive electrode connection terminal or a negative electrode connection terminal provided in one of the adjacent film-clad batteries is a negative electrode connection terminal or a positive electrode connection terminal provided in the other. An assembled battery, wherein a clearance is formed between adjacent film-clad batteries by the connected positive and negative electrode connection terminals. The exterior film containing the electrode group, the positive electrode conductive plate electrically connected to the positive electrode of the electrode group, and the negative electrode conductive plate electrically connected to the negative electrode of the electrode group is maintained in a reduced pressure state. And a plurality of film-clad batteries in which a part of the positive / negative electrode conductive plate is exposed to the outside are arranged adjacently,
The adjacent film-clad batteries are exposed surfaces of the positive electrode conductive plate or the negative electrode conductive plate provided in one film-clad battery, and the exposed surface of the negative electrode conductive plate or the positive electrode conductive plate provided in the other film-clad battery. The battery is connected via a conductor disposed between the two, and the conductor is disposed in a recess formed in at least one of the two exposed surfaces.   The assembled battery according to claim 4, wherein a clearance is formed between the adjacent film-clad batteries by the conductor.   6. The assembled battery according to claim 4, wherein a plurality of the recesses are formed in a lattice shape, and the conductor is disposed in each recess.

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