JP5099985B2 - Pack battery - Google Patents

Description

  The present invention relates to a battery pack that can accommodate a large number of secondary batteries, reduce the outer shape of the case, and make the structure stronger.

  In a battery pack that houses a plurality of secondary batteries in a case, it is important to increase the chargeable / dischargeable capacity while reducing the outer shape of the case. Furthermore, a battery pack that houses a large number of secondary batteries incorporates a control circuit that detects the remaining capacity and voltage of the battery and controls charging and discharging. In addition to improving safety, this battery pack can extend the life of the battery. This is because the battery can be controlled so as not to be charged / discharged under the condition of lowering the electrical characteristics. Thus, a battery pack for mounting a circuit board on a case has been developed. (See Patent Document 1)

In the battery pack of Patent Document 1, a control circuit that controls charging and discharging of a battery is mounted on a circuit board, and this is housed in a case together with a secondary battery. Since this battery pack houses a circuit board and a large number of secondary batteries in a case, it is difficult to efficiently dissipate heat generating electronic components provided on the circuit board. If a gap is provided in the case for heat dissipation, the outer shape of the case becomes large. Further, when the case is thinned, the strength is lowered. There are disadvantages such as failure of the electronic components that generate heat efficiently, failure at a high temperature, or shortened life.
JP 2005-56721 A

  The present invention has been developed for the purpose of solving such drawbacks of conventional battery packs. An important object of the present invention is to provide a battery pack capable of efficiently cooling electronic components while reducing the outer shape of the case.

The battery pack of the present invention has the following configuration in order to achieve the aforementioned object.
The battery pack includes an inner pack 4 that houses a plurality of secondary batteries 1 and a first circuit board 2 in a box-shaped inner case 3, an outer case 5 that houses the inner pack 4, and this outer battery And a second circuit board 6 disposed between the case 5 and the inner case 3. The plurality of secondary batteries 1 are arranged in parallel to each other in a plane parallel to the inner surface of the inner case 3, and the inner case is arranged in one or more rows so that both end faces are positioned on the same plane. 3 is stored. The first circuit board 2 is disposed between the inner surface of the inner case 3 and the secondary battery 1 in a posture parallel to the inner surface of the inner case 3. A second circuit board (6) is disposed to face the outer surface of the inner case in a posture orthogonal to the first circuit board (2) (3). Further, the inner case 3 is divided into a case unit 3A having a U-shaped cross section by dividing the top plate 3a and the bottom plate 3b in the middle and connecting the pair of case units 3A to the inside. The secondary battery 1 and the first circuit board 2 are accommodated.

  The battery pack of the present invention is a cylindrical battery in which a plurality of secondary batteries 1 are valleyd between adjacent secondary batteries 1, and the first circuit board 2 is interposed between the inner surface of the inner case 3. It can arrange | position between the secondary batteries 1 arrange | positioned in the state with a valley.

  In the battery pack of the present invention, a metal chassis 16 is provided inside the outer case 5 and outside the inner pack 4, and the outer case 5 can be reinforced by the metal chassis 16. The metal chassis 16 may be a metal plate bent in a U shape.

  In the battery pack of the present invention, the first circuit board 2 can be disposed inside the first substrate holder 11 having a peripheral wall and disposed in the inner case 3.

In the battery pack of the present invention, the case unit 3 A can have the inner surfaces of the top plate 3 a and the bottom plate 3 b as tapered surfaces that increase the inner width toward the edge.
In the battery pack of the present invention, the metal chassis 16 composed of two metal plates can be disposed on both sides of the inner pack 4.

  The battery pack of the present invention is characterized in that the electronic components can be efficiently cooled while reducing the outer shape. The first circuit board includes a first circuit board and a second circuit board separated from a circuit board on which a circuit for controlling charge / discharge of a battery is mounted, and a case having a double structure of an inner case and an outer case. This is because the second circuit board is disposed between the inner case and the outer case. In particular, in the battery pack according to claim 2 of the present invention, the inner case is provided with a secondary battery made of a cylindrical battery to provide a valley between the batteries, and the secondary battery and the inner case between which the valley is formed are provided. Since the first circuit board is disposed in the first circuit board, the first circuit board can be disposed by effectively utilizing the valley formed by arranging the cylindrical batteries. In addition, since the first circuit board is disposed inside the inner case, the circuit board can be protected by a double case including an inner case and an outer case. For this reason, since a thin and low-strength circuit board can be used for the first circuit board, the inner pack for mounting the first circuit board can be made extremely small. Since the first circuit board is disposed close to the secondary battery whose temperature is increased by charging and discharging, the electronic component mounted thereon cannot be cooled effectively. However, since the battery pack according to the present invention separates the circuit board into the first circuit board and the second circuit board, the heat generating electronic component that controls a large current is not mounted on the first circuit board, It can be mounted on a circuit board. For this reason, an electronic component having a small current or a small power, for example, a circuit for detecting the voltage or temperature of the secondary battery can be mounted on the first circuit board to prevent adverse effects caused by the heat of the secondary battery. For this reason, the inner circuit pack can be made smaller by reducing the thickness of the first circuit board and placing it closer to the secondary battery. Furthermore, the battery pack of the present invention can effectively dissipate heat by mounting the heat generating component on the second circuit board disposed outside the inner pack. This is because the electronic component of the second circuit board can radiate heat to the outside through the outer case.

  Embodiments of the present invention will be described below with reference to the drawings. However, the example shown below illustrates the battery pack for embodying the technical idea of the present invention, and the present invention does not specify the battery pack as follows.

  Further, in this specification, in order to facilitate understanding of the scope of claims, numbers corresponding to the members shown in the examples are indicated in the “claims” and “means for solving problems” sections. It is added to the members. However, the members shown in the claims are not limited to the members in the embodiments.

  The battery pack shown in FIGS. 1 to 11 is used, for example, as a power source for electrical equipment installed outdoors, such as a telephone repeater. Therefore, it is used from a low temperature to a high temperature, for example, at an external temperature of -30C to 80C. In addition, the battery pack for outdoor use is required to have excellent durability and strength.

  1 to 7 show the battery pack of the first embodiment, and FIGS. 8 to 11 show the battery pack of the second embodiment. The battery pack shown in these figures includes an inner pack 4, an outer case 5 housing the inner pack 4, and a second circuit board 6 disposed between the inner pack 4 and the outer case 5. With.

  The inner pack 4 stores a plurality of secondary batteries 1 and a first circuit board 2 in a box-shaped inner case 3. The inner case 3 is made of plastic, and the top plate 3a and the bottom plate 3b are divided in the middle to divide the case unit 3A into a U-shaped cross section. In this specification, the top plate 3a and the bottom plate 3b are specified on the basis of the drawings. In the drawing, the plate above the inner case 3 is the top plate 3a, and the lower plate is the bottom plate 3b. The pair of case units 3 </ b> A that are divided and formed are connected to each other to form a box shape that houses the secondary battery 1 and the first circuit board 2. The inner case 3 shown in FIG. 2 to FIG. 7 is formed into a shape that is divided into left and right parts at substantially the center of the top plate 3a and the bottom plate 3b. In the inner case 3 shown in FIGS. 9 to 11, the top plate 3a and the bottom plate 3b are divided at positions that are omnipresent on one side instead of the center. In FIG. 10, the inner case 3 has a left case unit 3A having a wide top plate 3a and a bottom plate 3b, and a right case unit 3A having a narrow top plate 3a and a bottom plate 3b. The case unit 3A shown in these figures is integrally formed with a top plate 3a at the upper edge of the rectangular side plate 3d, a bottom plate 3b at the lower edge, and an end face plate 3c at both ends, and the side portions are opened. It is molded into a rectangular box shape. The case unit 3A having this shape has a shape in which a peripheral wall including a top plate 3a, a bottom plate 3b, and an end face plate 3c is integrally formed around the side plate 3d. The pair of case units 3A that are divided and molded of plastic are connected by screws 17 with the edges of the peripheral walls formed by the top plate 3a, the bottom plate 3b, and the end face plate 3c abutting each other.

  The battery pack incorporates a first circuit board 2 and a second circuit board 6. The first circuit board 2 is disposed inside the inner case 3, and the second circuit board 6 is disposed outside the inner case 3 and inside the outer case 5. The first circuit board 2 does not mount an electronic circuit including a high-power electronic component that generates heat by flowing a large current. For example, the first circuit board 2 is mounted with a circuit that detects each battery voltage and battery temperature. A high-power electronic component that generates heat by flowing a large current and an electronic circuit including the high-power electronic component are mounted on the second circuit board 6. The first circuit board 2 is connected to the electrode of the secondary battery 1 via the lead wire 7 and the lead plate 8, and the second circuit board 6 is connected to the first circuit board 2 via the lead wire 9. Further, it is connected to the output of the secondary battery 1 through a thicker lead wire 10.

  The first circuit board 2 is disposed between the inner surface of the side plate 3d and the secondary battery 1 in a posture parallel to the inner surface of the inner case 3, that is, the side plate 3d. In the illustrated battery pack, the first circuit board 2 is placed in the first board holder 11 and stored in the inner case 3. The first substrate holder 11 is made of plastic and formed into a box shape with a peripheral wall. The first substrate holder 11 puts the first circuit board 2 inside the peripheral wall, fills the inside of the peripheral wall with an insulating resin (not shown), and covers the first circuit board 2 with the insulating resin. ing. With this structure, the first circuit board 2 can be insulated and disposed in the inner case 3. For this reason, even if electrolyte solution leaks from the secondary battery 1 in the inner case 3 or gas is released, the circuit board can be insulated and protected from the electrolyte solution and gas.

  The first circuit board 2 housed in the inner case 3 is protected by the inner case 3. Furthermore, the first circuit board 2 that is placed in the first substrate holder 11 and accommodated in the inner case 3 is protected by both the first substrate holder 11 and the inner case 3. With this structure, the first circuit board 2 and the first board holder 11 can be made thin and light. This is because they do not require strong strength.

  In the illustrated inner pack 4, the bottom surface side of the first substrate holder 11 is disposed on the secondary battery 1 side. In other words, the opening of the first substrate holder 11 is arranged on the side plate 3 d side of the inner case 3. In the inner pack 4, the bottom plate of the first substrate holder 11 is disposed between the first circuit board 2 and the secondary battery 1. In the inner pack, the bottom plate of the first substrate holder can be arranged opposite to the side plate of the inner case, contrary to this figure. In this inner pack, the electronic components fixed to the first circuit board are arranged so as to protrude in the valley formed between the secondary batteries, the first circuit board approaches the secondary battery, and the outer pack The outer shape of the case can be reduced. Moreover, the electronic component currently fixed to the surface can also be arrange | positioned in the trough made between secondary batteries, without accommodating a 1st circuit board in a 1st board | substrate holder. Furthermore, a through hole is provided in the bottom of the first substrate holder, and the electronic component fixed to the first circuit board is projected into the through hole, and the electronic component is disposed in the valley between the secondary batteries. You can also.

  The first circuit board 2 is connected to the secondary battery 1 via the lead wire 7 and the lead plate 8. In other words, the plurality of secondary batteries 1 are connected to each other by the lead plate 8, and the lead plate 8 is connected to the first circuit board 2 through the lead wires 7. Since the first circuit board 2 is fixed to the first board holder 11, both the first circuit board 2 and the first board holder 11 are connected to the secondary battery 1 via the lead wire 7 and the lead plate 8. Connected to

  The secondary battery 1 is a cylindrical lithium ion secondary battery. However, a square battery can be used as the secondary battery instead of the cylindrical battery. The secondary battery is not limited to a lithium ion secondary battery, and any other secondary battery such as a nickel metal hydride battery or a nickel cadmium battery can be used. As shown in FIGS. 6 and 10, the battery pack shown in FIG. 6 has a plurality of secondary batteries 1 arranged in parallel with each other and arranged in a plane parallel to the surface of the first circuit board 2. Are placed in the same plane and are stored in the inner case 3 in three rows. In the secondary batteries 1 arranged in three rows, the secondary batteries 1 in adjacent rows are arranged in the valley. Further, a spacer 12 made of an insulating material is disposed between the secondary batteries 1. In the illustrated inner pack 4, the secondary batteries 1 are arranged in three rows. However, in the inner pack, the secondary batteries can be arranged in one or two rows, or in four or more rows.

  The secondary battery 1 has a lead plate 8 connected to its end face. The lead plate 8 connects the secondary batteries 1 in parallel and connects them in series. The lead plate 8 shown in the figure is connected to the electrode surfaces of the six secondary batteries 1 by a method such as spot welding. In this inner pack 4, three secondary batteries 1 are connected in parallel to form one block, and 13 blocks connected in parallel are connected in series.

  The second circuit board 6 is disposed outside the inner pack 4 and inside the outer case 5. The second circuit board 6 is fixed inside the second board holder 13 made of plastic. The second substrate holder 13 is fixed to the upper surface of the inner pack 4. The second substrate holder 13 has a rectangular box shape that opens downward, is filled with an insulating resin 14, and covers the second circuit board 6 with the insulating resin 14. The inner case 3 shown in FIG. 2 is provided with connecting projections 15 that protrude from both sides of the upper surface to fix the second substrate holder 13 in place. A set screw (not shown) inserted through the connecting convex portion 15 fixes the second substrate holder 13 to the inner pack 4. The second circuit board 6 is connected to the first circuit board 2 and the secondary battery 1 through lead wires 9.

  In the illustrated battery pack, a metal chassis 16 is provided on the inner surface of the outer case 5. The metal chassis 16 is provided between the outer case 5 and the inner pack 4 to reinforce the case. The battery pack shown in FIG. 2 reinforces one side plate 5d, top plate 5a, and bottom plate 5b of the outer case 5 by bending one metal plate into a U-shaped cross section. The metal chassis 16 is bent into a shape that covers the outside of the inner pack 4 that fixes the second circuit board 6.

  The metal chassis 16 fixes the inner pack 4 that fixes the second substrate holder 13 on the inner side, and the outer case 5 on the outer side. The metal chassis 16 is provided with a screw hole 18 into which a set screw (not shown) for fixing the inner pack 4 and the outer case 5 is screwed. The set screw is screwed into the metal chassis 16 to fix the inner pack 4 and the outer case 5. ing. Further, a connector 19 and the like are also fixed to the metal chassis 16.

  In the battery pack shown in FIG. 8, the metal chassis 16 is composed of two metal plates. The two metal chassis 16 are disposed inside the outer case 5 and on both sides of the inner pack 4. The two metal chassis 16 are fixed to the inner pack 4 and the outer case 5 with screws. However, the metal chassis can be fixed to the inner pack and the second substrate holder. The illustrated metal chassis 16 is provided with an opening 16 </ b> A in order to insert the protruding portion 3 e of the inner pack 4. This structure can be reinforced by the metal chassis 16 without inserting the protrusion 3e of the inner pack 4 into the opening 16A of the metal chassis 16 and widening the width of the battery pack.

  Since the metal chassis 16 has a large area, a high power electronic component such as a diode or FET can be fixed and used together with a heat sink of the electronic component.

  The outer case 5 of the battery pack shown in FIGS. 1, 2 and 8 is formed of plastic into a shape in which the top plate 5a and the bottom plate 5b are divided into two at the center. Since this outer case 5 is divided into two on both sides, the dividing line is the longitudinal direction of the outer case 5. The pair of divided outer cases 5 are fixed to the metal chassis 16 and the inner pack 4 with screws that penetrate the side plate 5d. A pair of outer cases 5 connected to each other has a rubber-like elastic packing 20 sandwiched between contact surfaces. As shown in the enlarged sectional view of FIG. 5, the packing 20 is put in a connecting groove 21 provided on one abutting surface. In the connecting groove 21 into which the packing 20 is put, a convex strip 22 provided on the other contact surface is press-fitted. The packing 20 is sandwiched between the ridges 22 and the connecting grooves 21, and the outer case 5 connects the contact surface to the waterproof structure. An end face plate 5c of the outer case 5 is provided with an opening 5e of a connector 19 serving as an output terminal.

1 is a perspective view of a battery pack according to an embodiment of the present invention. It is a disassembled perspective view of the battery pack shown in FIG. It is a partially expanded horizontal sectional view of the battery pack shown in FIG. It is a vertical longitudinal cross-sectional view of the battery pack shown in FIG. It is a vertical cross-sectional view of the battery pack shown in FIG. It is a disassembled perspective view of the inner pack of the battery pack shown in FIG. It is a horizontal sectional view of the inner pack of the battery pack shown in FIG. It is a disassembled perspective view of the battery pack concerning the other Example of this invention. FIG. 9 is a partially enlarged vertical cross-sectional view of the battery pack shown in FIG. 8. It is a disassembled perspective view of the inner pack of the battery pack shown in FIG. It is a horizontal sectional view of the inner pack of the battery pack shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Secondary battery 2 ... 1st circuit board 3 ... Inner case 3A ... Case unit
3a ... top plate
3b ... Bottom plate
3c ... End plate
3d ... Side plate
3e ... protruding part 4 ... inner pack 5 ... outer case 5a ... top plate
5b ... Bottom plate
5c ... End plate
5d ... Side plate
5e ... opening 6 ... second circuit board 7 ... lead wire 8 ... lead plate 9 ... lead wire 10 ... thick lead wire 11 ... first substrate holder 12 ... spacer 13 ... second substrate holder 14 ... insulating resin 15 ... Connecting convex part 16 ... Metal chassis 16A ... Opening part 17 ... Screw 18 ... Screw hole 19 ... Connector 20 ... Packing 21 ... Connecting groove 22 ... Convex strip

Claims (7)

An inner pack (4) that houses a plurality of secondary batteries (1) and a first circuit board (2) in a box-shaped inner case (3), and an outer that houses the inner pack (4) A case (5) and a second circuit board (6) disposed between the outer case (5) and the inner case (3);
The plurality of secondary batteries (1) are arranged in parallel to each other and in a plane parallel to the inner surface of the inner case (3), and both the end faces are positioned on the same plane. Stored in the inner case (3)
The first circuit board (2) is disposed between the inner surface of the inner case (3) and the secondary battery (1) in a posture parallel to the inner surface of the inner case (3).
The second circuit board (6) is disposed opposite to the outer surface of the inner case (3) in a posture orthogonal to the first circuit board (2).
Further, the inner case (3) is divided into a case unit (3A) having a U-shaped cross-section by dividing the top plate (3a) and the bottom plate (3b) in the middle and a pair of case units. A battery pack in which (3A) is connected and the secondary battery (1) and the first circuit board (2) are accommodated therein.   The plurality of secondary batteries (1) are cylindrical batteries having a valley between adjacent secondary batteries (1), the first circuit board (2), the inner surface of the inner case (3), The battery pack according to claim 1, wherein the battery pack is disposed between the secondary battery (1) and the secondary battery (1) disposed in a state having a valley between the secondary batteries (1).   The metal chassis (16) is provided inside the outer case (5) and outside the inner pack (4), and the outer case (5) is reinforced by the metal chassis (16). The battery pack described.   The battery pack according to claim 3, wherein the metal chassis (16) is formed by bending a metal plate into a U-shape.   The battery pack according to claim 1, wherein the first circuit board (2) is arranged inside the first board holder (11) having a peripheral wall and arranged in the inner case (3).   The battery pack according to claim 1, wherein the case unit (3A) has inner surfaces of the top plate (3a) and the bottom plate (3b) as tapered surfaces that increase the inner width toward the edge. The battery pack according to claim 3, wherein a metal chassis (16) composed of two metal plates is disposed on both sides of the inner pack (4).

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