JP4089581B2 - Laminated battery - Google Patents

Description

  The present invention relates to a laminated battery, and in particular, a combination of a plurality of sealed batteries in which an electrode group in which a separator is interposed between a positive electrode and a negative electrode and an electrolytic solution are sealed with a composite film in which a metal foil is coated with a multilayer resin layer. The present invention relates to a laminated battery.

  2. Description of the Related Art In recent years, electronic devices such as notebook personal computers and mobile phones have been reduced in size and increased in functionality in combination with higher density and higher performance of CPUs and the like. A secondary battery such as a lithium ion battery is generally used as a power source for electronic devices. For this reason, with the miniaturization of electronic devices, there is an increasing demand for smaller and lighter secondary batteries.

  In order to meet such demands, a multilayer film in which both surfaces of a metal layer are coated with a resin layer is used as an exterior material, and an electrode group in which a separator is interposed between a positive electrode and a negative electrode and a power generation element such as an electrolyte solution are sealed. The technology of the sealed battery is disclosed (for example, refer to Patent Document 1).

JP 2001-256937 A

  However, since a sealed battery sealed with a multilayer film is generally vulnerable to dropping and impact, many inspections are included in assembly and manufacturing when assembling a sealed battery or when producing an assembled battery in which sealed batteries are combined in series or in parallel. Attention was paid. In addition, such a sealed battery generally requires a structure in which a tab (output terminal) having polarity is derived from the same side and the distance between the tabs is close, so that a short circuit is prevented.

  An object of the present invention is to provide a laminated battery that is easy to assemble and that is resistant to dropping and impact and does not cause a short circuit accident.

  In order to solve the above problems, the present invention provides a plurality of sealed batteries in which an electrode group in which a separator is interposed between a positive electrode and a negative electrode and an electrolytic solution are sealed with a composite film in which a metal foil is covered with a multilayer resin layer. In the combined battery, the sealed battery is held by two sandwiching frames that sandwich a seal portion around the composite membrane, and output terminals respectively derived from the positive and negative electrodes are located in the sandwiching frames. A groove is formed in the portion, and any one of the output terminals is in contact with a conductive member that is provided at one location of each holding frame and defines the bottom surface of the groove.

  In the present invention, since the sealed battery is held by sandwiching the seal portion around the composite membrane between the two holding frames, the periphery of the sealed battery is strengthened, impact resistance is improved, and handling during assembly is simple. And the sealing battery stacking operation can be performed safely. Since each holding frame has a groove formed in the part where the output terminal led out from the positive and negative electrodes is located, the output output from the positive and negative electrodes respectively. Since the terminals are held in the groove by two holding frames and the distance between the output terminals can be secured, it is possible to prevent a short circuit of the sealed battery, and either one of the output terminals is provided at one position of the holding frame. Since it is in contact with the conductive member that defines the bottom surface of the groove, the power of the sealed battery can be input and output through the conductive members provided on the two holding frames.

  In the present invention, in order to reduce the number of parts, the two holding frames have the same shape, and are arranged in the up and down direction so as to sandwich the output terminals respectively derived from the positive and negative electrodes by the grooves. preferable. In addition, if the sealed batteries are stacked in the vertical direction, and the conductive members of the two holding frames of the sealed batteries adjacent in the vertical direction are arranged in a symmetrical position, the sealed batteries adjacent in the vertical direction are Since the output terminals are symmetrically located by the conductive member, it is possible to prevent short-circuiting between the output terminals respectively derived from the positive and negative electrodes of the adjacent sealed batteries, and it is possible to connect the output terminals in series. That is, between the adjacent sealed batteries, the conductive members provided on the sandwiching frames adjacent in the vertical direction come into contact with each other, and the sealed batteries are connected in series. Furthermore, in order to reduce the size of the assembled battery, it is preferable that the positive and negative output terminals are led out to the same side of the holding frame. And if a some groove part is formed in 2 sides which a holding frame opposes, a sealed battery can be maintained in arbitrary temperature ranges by distribute | circulating a cooling medium to these groove parts.

  According to the present invention, since the sealed battery is held by sandwiching the seal portion around the composite membrane with the two holding frames, the periphery of the sealed battery is strengthened, impact resistance is improved, and handling during assembly is performed. Can be performed safely and can be safely stacked, and each holding frame has a groove formed in the part where the output terminal led out from the positive and negative electrodes is located. Since the output terminal is held in the groove by two holding frames and the separation distance between the output terminals can be secured, it is possible to prevent a short circuit of the sealed battery, and either one of the output terminals is located at one place of the holding frame. Since it is in contact with the conductive member provided to demarcate the bottom surface of the groove, it is possible to obtain an effect that the power of the sealed battery can be input / output via the conductive member provided on the two holding frames. Can do.

  Hereinafter, an embodiment of a laminated battery according to the present invention will be described with reference to the drawings.

(Constitution)
As shown in FIGS. 1 and 2, the laminated battery 14 of the present embodiment is composed of two types of frame batteries, a frame battery A <b> 11 having a flat sealed battery 9 and a frame battery B <b> 12.

  The sealed battery 9 is a composite film (multilayer film) in which a metal foil is coated with a multilayer resin layer, in which an electrode group in which a separator is interposed between a positive electrode and a negative electrode and an electrolytic solution are sealed. If it states, what was produced as follows can be used, for example.

(Preparation of positive electrode)
100 parts by weight of lithium manganate (LiMn ₂ O ₄ ) powder as an active material, 10 parts by weight of flaky graphite (average particle size: 20 μm) as a conductive material, and 10 parts by weight of polyvinylidene fluoride (PVDF) as a binder Then, N-methylpyrrolidone (NMP) as a dispersion solvent is added thereto, and the kneaded slurry is applied to both surfaces of an aluminum foil serving as a current collector. After drying the slurry and fixing the active material mixture on both sides of the aluminum foil, the slurry is cut into a predetermined strip shape, and an aluminum electrode terminal is connected to the aluminum foil.

(Preparation of negative electrode)
Apply 100 parts by weight of graphite powder as an active material, 10 parts by weight of PVDF as a binder, add NMP as a dispersion solvent to this, and coat the kneaded slurry on both sides of the rolled copper foil as a current collector To do. After drying the slurry and fixing the active material mixture layer on both sides of the rolled copper foil, the strip is cut into a predetermined size and a copper electrode terminal is connected to the rolled copper foil.

(Production of sealed battery)
It superposes | stacks alternately so that the polyethylene-made separator in which the microporous which accept | permits the movement of lithium ion was located may be located between the produced positive electrode and negative electrode. After the stacked electrode group is fixed with an adhesive tape, the electrode terminal derived from the positive electrode is connected to the positive electrode output terminal 7 made of aluminum, and the electrode terminal derived from the negative electrode is connected to the negative electrode output terminal 8 made of copper (FIG. 3).

  Next, the electrode group provided with the output terminal is covered with a multilayer film composed of a polyamide resin layer, an aluminum foil layer, and a polyethylene resin layer, and after injecting the electrolytic solution, around the entire multilayer film where the electrode group is located. The sealing part 10 is formed by applying thermal energy and sealing. At this time, the sealed battery 9 is formed by bringing the arrangement space of the electrode group in the multilayer film into a reduced pressure state and bringing the electrodes into close contact with each other at atmospheric pressure. For this reason, the sealed battery 9 has a flat shape in which the central portion where the electrode group and the electrolytic solution are disposed protrudes on both sides in a rectangular shape with respect to the seal portion 10 (see FIG. 3).

  As shown in FIGS. 2A and 3, the frame battery A <b> 11 includes two rectangular holding frames A <b> 1 having an opening at the center and a sealed battery 9. The central portion of the sealed battery 9 is inserted into the opening of the holding frame A1. For example, a polyamide resin can be used as the material of the holding frame A1.

  As shown in FIGS. 3 and 4A, the positive electrode output terminal 7 of the sealed battery 9 is provided on one side (hereinafter referred to as an output terminal side) that intersects the longitudinal direction of the holding frame A1 and is wider than the other side. A negative output terminal 8 is disposed. In the portion where the positive output terminal 7 and the negative output terminal 8 are located on the output terminal side, terminal grooves 5 that are slightly larger in width than these terminals and are continuously drilled in the length direction to both end surfaces of the output terminal side are formed. Yes. One of the terminal grooves 5 is made of nickel, and the bottom surface of the terminal groove 5 is formed (defined) by one surface of the block-shaped conductive portion 3. The surface of the conductive portion 3 opposite to the surface forming the bottom surface of the terminal groove 5 is the same surface as the surface of the output terminal side opposite to the surface where the terminal groove 5 is formed. That is, the portion of the output terminal side where the conductive portion 3 is disposed is notched, and the conductive portion 3 forms a terminal groove 5 so that the output terminal side is cut so that it is flush with the opposite surface of the terminal groove 5. It is fixed to the notch end surface with an adhesive.

  Two holding frames A1 having the same shape are used for the frame battery A11, and the positive output terminal 7 and the negative output terminal 8 are sandwiched between the terminal grooves 5 by reversing one holding frame A1 in the assembly process. Are disposed in the opposite direction in the vertical direction. At this time, the conductive part 3 contacts either the positive electrode output terminal 7 or the negative electrode output terminal 8 (in the frame battery A11, it contacts the negative electrode output terminal 8). Further, the sealing portion 10 of the sealed battery 9 is sandwiched by four sides including the output terminal sides of the two holding frames A1. During the superposition, the seal portion 10 and the holding frame A11 in contact with the seal portion 10 are bonded with an adhesive.

  As described above, the central portion of the sealed battery 9 is inserted into the opening of the holding frame A1, but the holding frame A1 protrudes slightly outward (vertical direction) from the surface of the central portion of the sealed battery 9 ( (See FIG. 2A). Further, as shown in FIG. 3, the outer size of the holding frame A1 other than the output terminal side is slightly larger than the sealed battery 10, and when the frame battery A11 is assembled, a space is formed around the seal portion 10 (hereinafter referred to as “this”). The space is referred to as a filling portion 13 (see FIG. 1). The filling portion 13 is preferably filled with an adhesive, a sealing material, a molten resin, or the like.

  As shown in FIG. 2 (B), the frame battery B12 includes two rectangular holding frames B2 having an opening at the center and the sealed battery 9, similarly to the frame battery A11. Yes. The two holding frames B2 have the same shape. 4A and 4B, the holding frame B2 is different from the holding frame A1 in that the conductive portion 4 and the terminal groove 6 on the output terminal side are the conductive portion 3 and the terminal groove 5 of the holding frame A1. It is arranged in a symmetrical position. Therefore, when the positive output terminal 7 and the negative output terminal 8 are sandwiched between the terminal grooves 5 by reversing one holding frame B2 in the assembly process, the conductive portion 4 comes into contact with the positive output terminal 7.

  As shown in FIG. 1, the stacked battery 14 is formed by stacking frame batteries A <b> 11 and frame batteries B <b> 12 alternately. By alternately laminating the frame battery A11 and the frame battery B12, the conductive part 3 of the frame battery A11 and the conductive part 4 of the frame battery B12 are in contact with each other, and the sealed battery 9 of the frame battery A11 and the frame battery B12 is in series. Connected.

(Action etc.)
Next, the operation and the like of the laminated battery 14 of the present embodiment will be described.

  The frame batteries A11 and B12 constituting the laminated battery 14 of this embodiment are sealed with a small number of parts because the sealed battery 9 is held by sandwiching the seal portion 10 between the two holding frames A1 and B2, respectively. The periphery of the battery 9 is strengthened, impact resistance is improved, and handling during assembly is simplified. In addition, terminal grooves 5 and 6 are formed in the portions where the positive electrode output terminal 7 and the negative electrode output terminal 8 of the sealed battery 9 are located on the output terminal sides of the frame batteries A11 and B12. Since the terminal 8 is sandwiched between the terminal grooves 5 and 6 by two holding frames A1 and B2, respectively, and a separation distance between the positive electrode output terminal 7 and the negative electrode output terminal 8 can be secured, the sealed battery 9 of the frame batteries A11 and B12 can be secured. A short circuit (internal short circuit) of the output terminal can be prevented. Further, the negative electrode output terminal 8 and the positive electrode output terminal 7 of the frame batteries A11 and B12 are provided at one location of the holding frames A1 and B2, respectively, define the bottom surfaces of the terminal grooves 5 and 6, and continue to both end surfaces of the output terminal side. Since the conductive parts 3 and 4 are in contact with each other, the power of the sealed battery 9 can be input and output through the conductive parts 3 and 4.

  In addition, the frame batteries A11 and B12 constituting the laminated battery 14 of the present embodiment are held so that the sealed battery 9 is sandwiched between the two holding frames A1 and B2, respectively, so that the frame batteries A11 and B12 are manufactured. In addition to the sealed battery 9, only two types of holding frames A1 and B2 having the same shape need be prepared. Accordingly, the number of parts for producing the frame batteries A11, B12 and the laminated battery 14 can be reduced, and the number of work steps required for producing the laminated battery 14 can be reduced. As a result, the cost of the laminated battery 14 can be reduced. Can do. In addition, since the polyamide material or the like that is easily available can be used as the material of the holding frames A1 and B2, a reduction in the cost of the holding frames A1 and B2 itself can be expected.

  Furthermore, since the conductive parts 3 and 4 of the frame batteries A11 and B12 are symmetrical on the output terminal side, the laminated battery 14 of the present embodiment has a holding frame A1 between the frame batteries A11 and B12 adjacent in the vertical direction. Since the conductive portions 3 and 4 provided in B2 are arranged at symmetrical positions (see FIG. 1), it is possible to prevent a short circuit (external short circuit) between the output terminals of the frame batteries A11 and B12 and to prevent the frame battery A11. By alternately laminating B12, the conductive portions 3 and 4 are connected, so that the series connection of the sealed batteries 9 can be performed very simply.

  And in the laminated battery 14 of this embodiment, since the positive electrode output terminal 7 and the negative electrode output terminal 8 were collectively arrange | positioned at the output terminal side of frame battery A11, B12, size reduction of the laminated battery 14 can be achieved. it can.

  In this embodiment, an example in which a rectangular block shape is used as the shape of the conductive portions 3 and 4 has been described. However, in order to strengthen the fixing to the holding frames A1 and B2, the holding frames A1 and B2 are fitted. A shape that can be matched may be adopted. Moreover, although the example which used the block made from nickel for the conductive parts 3 and 4 was shown, this invention is not restricted to this, For example, it is made to make a conductive part by vapor-depositing conductive materials, such as nickel, on the resin-made rectangular block. May be.

  Further, in the present embodiment, an example in which the seal portion 10 of the sealed battery 9 is bonded to the holding frames A1 and B2 with an adhesive has been described. However, welding may be performed by applying energy such as ultrasonic waves or heat. Good.

  Further, in the present embodiment, an example in which the positive electrode output terminal 7 and the negative electrode output terminal 8 are led out to the same output terminal side is shown, but the present invention is not limited to this, and the positive electrode output terminal 7, the negative electrode output terminal 8, May be derived to different sides of the holding frames A1 and B2.

  Further, in the present embodiment, the frame batteries A11 and B12 in which the filling portion 13 is formed are illustrated. However, as shown in FIG. 5, the sealing portion 10 is simply accommodated in advance so that the filling portion 13 does not exist. The laminated battery 14 can also be configured by laminating the frame batteries C15 and D16 in which the grooves are formed. In this way, since it is not necessary to fill the filling portion 13 with an adhesive or the like, the number of assembling steps can be further reduced.

  Furthermore, as shown in FIG. 6, the laminated battery 14 can also be configured by using a frame battery E <b> 19 in which a plurality of grooves 17 are formed on two opposing sides of the holding frame C <b> 18 instead of the frame batteries A <b> 11 and B <b> 12. . By forming such a groove 17, a cooling medium such as cooling air can be passed. By adopting the air cooling structure by the groove 17, the sealed battery 9 can be maintained in an arbitrary temperature range.

  The laminated battery of the present invention is improved in assemblability and strong against dropping and impact, so that no short circuit accident occurs. Therefore, it contributes to manufacturing, sales, etc., and can be used industrially.

It is a front view of the laminated battery of embodiment to which this invention is applied. (A) is an external appearance perspective view of the frame battery A which comprises the laminated battery of embodiment, (B) is an external appearance perspective view of the frame battery B. FIG. It is a disassembled perspective view of the frame battery A which comprises the laminated battery of embodiment. (A) is an external appearance perspective view of holding frame A used for frame battery A which constitutes a laminated battery of an embodiment, and (B) is an external perspective view of holding frame B used for frame battery B. It is a front view of the laminated battery of other embodiment to which this invention is applied. It is an external appearance perspective view of the frame battery which comprises the laminated battery of another embodiment to which this invention is applied.

Explanation of symbols

1 Holding frame A (clamping frame)
2 Holding frame B (clamping frame)
3, 4 Conductive part (conductive member)
5, 6 Terminal groove (groove)
7 Positive output terminal 8 Negative output terminal 9 Sealed battery 10 Seal part 14 Stacked battery 17 Groove (groove part)
18 Holding frame C (clamping frame)

Claims (6)

  In a laminated battery in which a plurality of sealed batteries in which a group of electrodes in which a separator is interposed between a positive electrode and a negative electrode and an electrolytic solution are sealed with a composite film in which a metal foil is coated with a multilayer resin layer are combined, It is held by two holding frames that hold a seal portion around the composite membrane, and each holding frame is formed with a groove in a portion where an output terminal derived from each of the positive and negative electrodes is located, and the output terminal Any one of these is provided in one place of each said holding frame, and is contacting the electroconductive member which demarcates the bottom face of the said groove | channel, The laminated battery characterized by the above-mentioned.   2. The laminated battery according to claim 1, wherein the two holding frames have the same shape, and are disposed in the up and down direction so as to sandwich the output terminals respectively derived from the positive and negative electrodes. .   The sealed battery is stacked in a vertical direction, and the two holding frames between the sealed batteries adjacent in the vertical direction are arranged so that the conductive member is in a symmetrical position. 1. The laminated battery according to 1.   The laminated battery according to claim 3, wherein the sealed batteries are connected in series by contacting conductive members provided on the holding frames adjacent in the vertical direction between the adjacent sealed batteries.   The laminated battery according to claim 1, wherein the positive and negative output terminals are led out to the same side of the holding frame.   The multilayer battery according to claim 1, wherein a plurality of grooves are formed on two opposing sides of the holding frame.