JP4128457B2 - battery - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery, and more particularly to a battery in which an electrode plate group in which a positive electrode plate and a negative electrode plate are laminated via a separator is housed in an outer case together with an electrolytic solution.
[0002]
[Prior art]
In recent years, expectations for electric vehicles and hybrid vehicles that use fuel cells and secondary batteries have increased due to global environmental problems, and secondary batteries used for their power sources are desired to be smaller, lighter and have higher capacity and higher output. Yes. As secondary batteries satisfying such demands, lithium ion secondary batteries and nickel metal hydride batteries have been put into practical use.
[0003]
As this type of battery having a light and inexpensive configuration, for example, a battery shown in FIG. 4 is known. Referring to FIG. 4, a rectangular cup-shaped case body 22 is formed from a laminate sheet in which a synthetic resin film is bonded to an aluminum foil, and the opening of the case body 22 is formed by a lid sheet 23 made of a laminate sheet. An outer case 21 is formed so as to cover the battery 20 by accommodating and arranging an electrode plate group 24 in which a plurality of rectangular positive electrode plates and negative electrode plates are laminated via a separator in the outer case 21 together with an electrolyte. Has been. The connection tabs 25a and 25b extending from the positive and negative plates of the electrode plate group 24 are connected to the positive and negative strip-like electrode terminals 26a and 26b, respectively, and the electrode terminals 26a and 26b are connected to the case body 22. A portion between the outer peripheral flange 22 a and the outer peripheral portion of the lid sheet 23 is inserted through a sealing material 27 so as to protrude outside the outer case 21.
[0004]
[Problems to be solved by the invention]
However, in the battery 20 configured as shown in FIG. 4, the electrode terminals 26a and 26b are thin, so that there is a problem that the resistance is large and the output voltage is lowered at the time of high output. In order to cope with this problem, the electrode terminals When the thickness dimension of 26a, 26b is increased, there is a problem that sealing between the case main body 21 and the lid sheet 22 becomes difficult, and the battery 20 having such a configuration is a low-cost configuration, but the output is increased. There was a limit.
[0005]
Further, since the case body 21 is formed into a rectangular cup shape using a flat laminate sheet, there is a limit to the depth thereof, and there is a limit to increasing the thickness and increasing the output. There is also a problem in that the yield of the laminate sheet is poor and the cost is high because a large wrinkle holding margin is required at the time of cup molding.
[0006]
In view of the above-described conventional problems, an object of the present invention is to provide a battery that does not cause a voltage drop due to the resistance of an electrode terminal even at a high output and can be configured with a lightweight and inexpensive outer case.
[0007]
[Means for Solving the Problems]
The battery according to the present invention is a battery in which an electrode plate group in which a positive electrode plate and a negative electrode plate are laminated via a separator is accommodated in an outer case together with an electrolytic solution. The outer case includes a frame and a peripheral portion of the frame. Ri consists the laminate sheet are welded to form a closed space for accommodating the electrode plate group, wherein the frame body, the connecting frame for connecting one ends of the end frame and across frames of a pair of supporting both ends of the electrode plate group The laminate sheet is wound between both end frames, both side edges thereof are welded to the outer periphery of the both end frames, both ends thereof are welded to the connecting frame, and the electrode terminals are attached to the end frame. Since the electrode terminals are attached to the frame, columnar terminals with low resistance can be used, so that the output voltage does not decrease even at high output, and the frame and laminate sheet The exterior case is configured by combining Therefore, it can be made lighter and cheaper than the case where the entire exterior case is made of a metal or synthetic resin rigid case, and the peripheral edge of the laminate sheet is used as a frame. Since it is welded, the yield of the laminate sheet is good and the cost can be further reduced. Further, since the frame body is composed of both end frames supporting both ends of the electrode plate group and a connecting frame connecting the both end frames, both ends of the electrode plate group can be stably supported by the frame body, and both ends By laminating a laminate sheet between frames, welding both side edges to the outer periphery of both end frames, and welding both ends to the connecting frame, a sealed space can be easily and reliably formed using a flat laminate sheet It can be manufactured inexpensively with a simple manufacturing process.
[0008]
If the laminate sheet is composed of a metal foil and a synthetic resin film, the metal foil can reliably prevent leakage of internal gas and ensure the required strength with a thin sheet thickness. This is preferable.
[0010]
In addition, when the frame is formed of a band-shaped laminate sheet formed in a shallow groove shape in which reinforcing ends are erected on the periphery, the frame is formed into a U shape in which one end of each end frame is connected by a connecting frame. Can be constructed at a low cost since it is formed of a laminate sheet, and can be manufactured at a lower cost because it does not require cup molding.
[0011]
Also, if at least the connecting frame is made of an insulating member and the electrode terminals are respectively attached to the both end frames, the electrode terminals of the respective polarities may be simply attached to the both end frames of the same configuration, and the manufacturing is further reduced. be able to.
[0012]
Further, the frame body may be formed of a metal plate press-molded product, in which case the electrode terminal of either polarity is mounted via an insulating material, so that the electrode terminal is disposed at an arbitrary position. can do.
[0013]
Further, the frame body may be formed of a synthetic resin molded product, so that the frame body can be manufactured with high productivity and at low cost, and the electrode terminals of each polarity may be simply attached to both end frames. It can be manufactured at low cost.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the configuration of the battery according to the first embodiment of the present invention will be described with reference to FIG.
[0015]
In FIG. 1, reference numeral 1 denotes a battery, which is configured by housing an electrode group 3 in which a positive electrode plate and a negative electrode plate are wound via a separator in an outer case 2 together with an electrolytic solution.
[0016]
The outer case 2 includes both end frames 5a and 5b in which a joint portion with the laminate or the whole is coated with a resin such as PP on a conductive material such as iron, SUS, Al, or Ni that supports both ends of the electrode plate group 3. And a frame 4 having a U-shape comprising a connecting frame 6 for connecting one ends of both end frames 5a and 5b, and a laminate formed by bonding a synthetic resin film such as PP to aluminum foil on the frame 4. The peripheral edge of the sheet 7 is welded to form a sealed space for accommodating the electrode plate group 3. In the example of illustration, the frame 4 is comprised by the strip | belt-shaped laminate sheet | seat 8 shape | molded in the shallow groove shape which erected the reinforcement collar 8a on the periphery, and the peripheral part of the laminate sheet 7 is welded to the reinforcement collar 8a. . In addition, the welding method of an exterior case and a laminate sheet etc. is made to melt | dissolve a thermoplastic resin with heat | fever by ultrasonic welding, heat welding, high frequency welding, etc., and it is made to adhere by pressurizing and cooling. The heating temperature is a temperature at which the resin is heated up to the melting point of the resin.
[0017]
Columnar positive and negative electrode terminals 9 a and 9 b are attached to one end frame 5 a of the frame body 4. One electrode terminal 9a is supported by penetrating through the insulating mechanism 11 in the holding cylinder portion 10 attached to the end frame 5a by caulking, and the other electrode terminal 9b is directly attached to the end frame 5a by caulking. ing. Further, a connection member 12a to which one current collector 13a of the electrode plate group 3 is welded is fixed to one electrode terminal 9a by caulking, and the other current collector of the electrode plate group 3 is fixed to the other end frame 5b. A connection member 12b to which the electric body 13b is connected by welding is fixed by welding. Here, the electrode terminal of the positive electrode is made of iron, SUS, Al, and Ni, and the electrode terminal of the negative electrode is made of Cu or Cu plated with Ni. In addition to caulking, the electrode terminal is secured by screw fastening, welding, or the like.
[0018]
The electrode plate group 3 is formed by winding a flat core 3a made of a synthetic resin molded product with the core material of the positive electrode plate exposed at one end and the core material of the negative electrode plate exposed at the other end. The current collectors 13a and 13b are welded to the core material of the positive electrode plate or negative electrode plate exposed at both ends of the electrode plate group 3 by laser beam welding, electron beam welding, or the like. Here, a resin having an electrolytic solution resistance such as PP or PE is used for the core.
[0019]
According to the battery 1 having the above configuration, since the columnar electrode terminals 9a and 9b having low resistance are mounted on the frame body 4, the output voltage does not decrease even at high output. Further, since the exterior case 2 is configured by combining the frame body 4 and the laminate sheet 7, it is configured to be lighter and cheaper than the case where the whole is configured by a metal or synthetic resin rigid case. Further, since the peripheral edge of the laminate sheet 7 is welded to the frame body 4, the yield of the laminate sheet 7 is good, and the cost can be further reduced. In addition, since the laminate sheet 7 is formed by bonding a synthetic resin film to a metal foil such as an aluminum foil, it is possible to reliably prevent leakage of internal gas with the metal foil and a thin sheet thickness. The required strength can be ensured.
[0020]
Further, since the frame body 4 is composed of both end frames 5a and 5b that support both ends of the electrode plate group 3 and a connecting frame 6 that connects the both end frames 5a and 5b, both ends of the electrode plate group 3 are connected to each other. By wrapping the laminate sheet 7 between the both end frames 5a, 5b and welding the both side edges to the outer periphery of the both end frames 5a, 5b and welding both ends to the connecting frame 6, A sealed space can be easily and reliably formed using the flat laminate sheet 7, and can be manufactured at low cost by a simple manufacturing process.
[0021]
Further, since the frame body 4 is composed of a strip-shaped laminate sheet 8 formed in a shallow groove shape with a reinforcing rod 8a standing on the periphery, the frame body 4 can be constructed with a laminate sheet at a low cost, and a cup Since there is no need for molding, the yield can be improved and it can be manufactured at a lower cost.
[0022]
Next, a second embodiment of the battery of the present invention will be described with reference to FIG.
[0023]
In the said 1st Embodiment, the frame body 4 formed by shape | molding the strip | belt-shaped laminate sheet 8 in the U-shape which consists of both ends frame 5a, 5b and the connection frame 6, and a cross-sectional shallow groove shape is used, and the one end Although an example in which a pair of electrode terminals 9a and 9b are mounted in parallel on the frame 5a has been shown, in the present embodiment, as shown in FIG. 2, the electrode terminals 9a and 9b are disposed on both end frames 15a and 15b , respectively. ing. The frame body 4 is composed of a pair of shallow dish-shaped end frames 15a and 15b formed separately and a connecting frame 16 which is similarly shallow dish-shaped and has concave portions facing inward, and the end frames 15a and 15b. The both ends of the connecting frame 16 are joined to one end of the frame. The end frames 15a and 15b and the connecting frame 16 can be formed of a laminate sheet molded product or a metal plate press molded product.
[0024]
Also in this embodiment, the same operation effect as the above-mentioned embodiment can be produced, and the frame body 4 is composed of both end frames 15a and 15b having a simple shape and a connecting frame 16, and both end frames 15a and 15b have the same shape. Therefore, it can be manufactured at a low cost.
[0025]
Next, a third embodiment of the battery of the present invention will be described with reference to FIG.
[0026]
In the second embodiment, the end frames 15a and 15b and the connecting frame 16 constituting the frame body 4 are formed of conductive members while the electrode terminals 9a and 9b are disposed on the both end frames 5a and 5b, respectively. For this reason, the example in which one electrode terminal 9a is pierced and supported by the holding cylinder portion 10 through the insulating mechanism 11 as in the first embodiment is shown. However, in this embodiment, each of the both end frames 15a and 15b is directly The electrode terminals 9a and 9b are arranged, and both end frames 15a and 15b are connected by a connecting frame 17 made of an insulating member such as a synthetic resin to constitute the frame body 4. Note that not only the connecting frame 17 but also one or both of the end frames 15a and 15b may be formed of an insulating member.
[0027]
In the present embodiment, the same effects as the above-described embodiment are obtained, and both the end frames 15a and 15b are insulated, so that the connection terminals 9a and 9b and the connection members 12a and 12b are simply connected to the both end frames 15a and 15b, respectively. It is only necessary to mount the device, the configuration is simple, and the configuration can be made inexpensively. Moreover, if the whole frame 4 is comprised with a synthetic resin molded product, a frame can be produced with good productivity and low cost.
[0028]
The present invention is not limited to the one shown in the above embodiment, and for example, the entire frame 4 may be constituted by a press-formed product of a metal plate. In that case, as shown in the first embodiment. In addition, the electrode terminal can be disposed at an arbitrary position by mounting the electrode terminal of any one polarity via an insulating material. Further, the overall shape of the frame body 4 is not limited to the U-shape in which one ends of both end frames 5a and 5b are connected by the connection frame 6, and one or more arbitrary portions of the end frames 5a and 5b are connected to the connection frame. Needless to say, the configuration connected at 6 may be used.
[0029]
【The invention's effect】
According to the battery of the present invention, the outer case is constituted by the frame body on which the electrode terminals are mounted, and the laminate sheet that forms a sealed space in which the peripheral portion is welded to the frame body to accommodate the electrode plate group. Column terminals with low resistance can be used for the electrode terminals attached to the body, so that the output voltage does not decrease even at high output, and the frame and laminate sheet are combined, so the whole Compared to the case made of metal or synthetic resin with high rigidity, it can be made lighter and cheaper, and since the periphery of the laminate sheet is welded to the frame, the yield of the laminate sheet is also increased. It is advantageous that the cost can be further reduced.
[Brief description of the drawings]
1A and 1B show a battery according to a first embodiment of the present invention, in which FIG. 1A is a front view of a part of the battery, and FIG. 1B is a cross-sectional view taken along line AA in FIG.
FIGS. 2A and 2B show a battery according to a second embodiment of the present invention with a laminate sheet removed, wherein FIG. 2A is a front view and FIG. 2B is a cross-sectional view taken along line BB in FIG.
FIG. 3 is a partial cross-sectional front view showing a battery according to a third embodiment of the present invention with a laminate sheet removed.
FIG. 4 is a perspective view showing a battery of a conventional example with a part of an exterior case cut away.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Battery 2 Exterior case 3 Electrode group 4 Frame body 5a, 5b End frame 6 Connection frame 7 Laminate sheet 8 Band-shaped laminate sheet 8a Reinforcement rod 9a, 9b Electrode terminal 15a, 15b End frame 16 Connection frame 17 Connection frame which consists of an insulating member

Claims (3)

In a battery in which an electrode plate group in which a positive electrode plate and a negative electrode plate are laminated via a separator is accommodated in an outer case together with an electrolyte solution, the outer case has a frame body, and a peripheral portion is welded to the frame body. Ri consists a laminate sheet for forming an enclosed space for housing a, the frame is composed of a connecting frame for connecting one ends of the end frame and across frames of a pair of supporting both ends of the electrode plate group, wherein the laminate The battery is characterized in that the sheet is wound between both end frames, both side edges thereof are welded to the outer periphery of the both end frames, both ends thereof are welded to the connecting frame, and the electrode terminals are mounted to the end frame. . The battery according to claim 1, wherein the laminate sheet is formed by bonding a synthetic resin film to a metal foil. At least connecting frames are constituted by an insulating member, a battery of claim 1, wherein each end frame fitted with electrode terminals.

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