JP4878890B2 - Pack battery - Google Patents

Description

  The present invention relates to a battery pack in which a plurality of batteries are connected linearly in series.

The battery pack can increase the output voltage by increasing the number of batteries connected in series. For this reason, battery packs used in applications requiring high output voltage, such as electric motorcycles and electric bicycles, have a plurality of batteries connected in series to increase output. In addition, a battery pack that has many batteries connected in series detects the voltage of each battery and improves safety by charging and discharging the battery while preventing overcharge and overdischarge of the battery from the detected voltage. In addition, the battery can be prevented from being deteriorated during charging and discharging, thereby extending the life. The battery pack that realizes this is connected to the positive and negative electrodes of each battery connected in series to the circuit board, and each battery voltage is detected by a protection circuit mounted on the circuit board to generate a charge / discharge current. Controlling. A battery pack has been developed in which the electrodes of batteries connected in series are connected to a circuit board. (See Patent Document 1)
JP-A-10-308205

  In Patent Document 1, a plurality of batteries are connected in parallel with a connection metal plate welded to an end face electrode of the battery, and the batteries connected in parallel are further connected in a straight line while being connected in series. The battery pack having this structure has a drawback that when the number of batteries connected in parallel is reduced and the number of batteries connected in series is increased, the whole becomes an elongated rod shape and the strength is lowered. In particular, there is a drawback that the bending strength is weakened. The disadvantage that the bending strength is lowered due to the elongated shape can be prevented by increasing the number of batteries connected in parallel to increase the thickness. However, since the thickness and length of the battery pack are limited depending on the application to be used, there is an adverse effect that the application is limited if the battery pack is thickened to improve the strength. Also, the elongated battery pack can improve the bending strength by fixing the reinforcing material in parallel. However, the battery pack for fixing the reinforcing material has a drawback that it is heavy and large in addition to the high component cost and manufacturing cost.

  The present invention has been developed for the purpose of solving such drawbacks. An important object of the present invention is to provide a battery pack capable of improving bending strength without using a special member while connecting a large number of batteries in a straight line in series.

The battery pack of the present invention has the following configuration in order to achieve the aforementioned object.
The battery pack is connected to a plurality of battery blocks 3, 33, and 53 that store the battery 1 in the cell holders 2, 32, and 52, and to an end face electrode of the battery 1 that is stored in the cell holders 2, 32, and 52. A plurality of battery blocks 3, 33, 53 are connected in a straight line to form battery rods 4, 34, 54, and a connecting metal plate 5 for connecting the batteries 1 stored in the cell holders 2, 32, 52 in series. A circuit board 6 arranged in parallel with the battery rods 4, 34, 54 connected in a straight line with the connection metal plate 5 and connecting the connection metal plate 5, and the circuit board 6 And a substrate holder 7 that is disposed in parallel with the battery rods 4, 34, 54 and connects the cell holders 2, 32, 52 of the battery blocks 3, 33, 53.

  The battery pack according to claim 2 of the present invention has the storage cylinders 8, 38, 58 in which the cell holders 2, 32, 52 of the battery blocks 3, 33, 53 store a plurality of batteries 1 in a parallel posture. A plurality of batteries 1 stored in the storage cylinders 8, 38, 58 are connected in parallel by a connection metal plate 5. In particular, in the battery pack according to claim 3 of the present invention, the cell holders 2, 32, 52 of the battery blocks 3, 33, 53 have the storage cylinders 8, 38, 58 for storing the three batteries 1 in a stacked state. The substrate holder 7 is connected to the valleys of the batteries 1 that are arranged in a stacked state.

  Further, in the battery pack of claim 4 of the present invention, the reinforcing metals 45 and 65 are fixed to the side surfaces of the battery rods 34 and 54, and the connecting portions of the battery blocks 33 and 53 are reinforced by the reinforcing metals 45 and 65, The battery rods 34 and 54 have a stronger structure.

  Further, the battery pack of claim 5 of the present invention is provided with a connection hook 47 that opens the connection hole 46 in the reinforcing metal 45 and is inserted into the connection hole 46 and connected to the cell holder 32 of the battery block 33. Since the connecting hook 47 of the cell holder 32 is inserted into the connecting hole 46 of the reinforcing metal 45 and the reinforcing metal 45 is connected to the cell holder 32, the cell holder 32 is connected to the reinforcing metal 45 easily and easily. it can.

  The battery pack of the present invention is characterized in that the bending strength can be improved without using a special member while connecting a large number of batteries in a straight line in series. The battery is housed in a cell holder to form a battery block, which is connected in a straight line with a connecting metal plate connected to the end electrode of the battery to connect the batteries in series to form a battery rod. This is because a substrate holder that accommodates the circuit board is fixed in parallel, and the battery rod that linearly connects the plurality of battery blocks is reinforced with the substrate holder. In particular, the present invention has a feature that the battery rod can be reinforced without using a special member because the substrate holder for storing the circuit board connected to each battery block is also used for reinforcing the battery rod. .

  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.

  1 to 4 show a battery pack used in an electric motorcycle that runs on an engine and a motor. However, the present invention does not specify the use of the battery pack for an electric motorcycle. It can be used for all applications in which a plurality of batteries are connected in series to increase the output voltage.

  2 shows a state in which the upper cover 9A of the outer case 9 of the battery pack of FIG. 1 is removed, and FIGS. 3 and 4 show a state in which the entire outer case 9 is removed. The battery pack from which the outer case 9 shown in FIGS. 3 and 4 is removed is a battery rod 4 in which a plurality of battery blocks 3 are linearly connected. A substrate holder 7 that accommodates the circuit substrate 6 is fixed in parallel with the battery rod 4.

  As shown in FIG. 5, the battery block 3 stores the battery 1 in the cell holder 2. In the illustrated battery block 3, three cylindrical batteries are arranged in a stacked state and stored in the cell holder 2. In this battery block 3, the battery 1 is a cylindrical battery, but the battery is not specified as a cylindrical battery. The battery can also be a square battery. Further, the battery 1 is a lithium ion secondary battery. The lithium ion secondary battery has a large charge capacity with respect to weight and volume, and can increase the output capacity of the battery pack. However, a nickel metal hydride battery or a nickel cadmium battery can also be used as the battery.

  The cell holder 2 is entirely formed of an insulating plastic. In the illustrated battery block 3, a storage cylinder 8 that stores a plurality of batteries 1 in a parallel posture is provided in the cell holder 2, and the plurality of batteries 1 are stored in the storage cylinder 8. The storage cylinder 8 has a cylindrical shape whose inner diameter is substantially equal to the outer diameter of the cylindrical battery 1 so that the cylindrical battery 1 can be inserted. The cell holder 2 is made of plastic in a shape that is divided into two in the middle of the cylinder. The cell holder 2 molded in two parts is joined by ultrasonic welding of the contact edges to each other, or by bonding, or by a fitting structure, and further by screwing and joining. Structure. The cell holder 2 can be connected so as not to be displaced easily as an attachment structure in which the contact edge can be connected to a fixed position. The cell holder 2 having this structure can reduce the difference due to the draft of the inner diameter of the storage cylinder 8. However, the entire cell holder can be integrally formed of plastic.

  Further, the battery block 3 shown in the figure is provided with a storage cylinder 8 in the cell holder 2 for storing three batteries 1 in a stacked state. The storage of the batteries 1 in a stacked state is an arrangement in which the three batteries 1 are stacked in a parallel posture so that the third battery 1 is positioned in the valley between the two adjacent batteries 1. The arrangement is such that the centers of the three batteries 1 are located at the vertices of a triangle in a cross section perpendicular to the axial direction of 1. Therefore, the cell holder 2 is connected so that the three storage cylinders 8 are parallel to each other and the central axis thereof is positioned at the apex of the triangle. The cell holder 2 that connects the batteries 1 in a stacked state can securely store the batteries 1 with excellent space efficiency. The storage cylinder 8 is open at both ends so that the connection metal plate 5 can be connected to the end of the battery 1 to be inserted.

  The cell holders 2 are linearly connected to each other in a state in which the battery 1 is housed to form a battery rod 4. The battery rod 4 is connected to the substrate holder 7 and reinforced by the substrate holder 7. Each cell holder 2 is connected to the substrate holder 7, and the battery rod 4 is connected to the substrate holder 7. The cell holder 2 shown in FIG. 5 is provided with a fixed boss 10 connected to the substrate holder 7 which is integrally molded with plastic. The fixed boss 10 is a columnar shape protruding from the storage cylinder 8 to the outside, and has a female screw hole (not shown) at the center. A set screw 11 penetrating the substrate holder 7 is screwed into the female screw hole of the fixed boss 10 to connect the cell holder 2 to the substrate holder 7.

  The cell holder 2 connecting the plurality of storage cylinders 8 has a valley space 12 between the adjacent storage cylinders 8. The cell holder 2 connecting the three storage cylinders 8 has three valley spaces 12. In the cell holder 2 of FIGS. 4 to 6, the substrate holder 7 is disposed in one valley space 12, and a connecting rod 13 is provided in another valley space 12. The cell holder 2 is provided with a connecting rod 13 connected to the adjacent cell holder 2 by integrally molding with plastic. The connecting rods 13 are provided in the valley space 12 of the cylindrical storage cylinder 8 at both ends of the cell holder 2. In this cell holder 2, the connecting rods 13 of the adjacent cell holders 2 are stacked, and the cell holders 2 are arranged in a straight line. 2 can be connected and fixed. The set screw 14 passes through one connecting rod 13 and is screwed into the other connecting rod 13, or passes through the pair of connecting rods 13 and screws a nut at the tip to connect the pair of connecting rods 13.

  Further, the battery rod 34 shown in FIGS. 7 and 8 has a reinforcing metal 45 fixed to the side surface and is reinforced by both the substrate holder 7 and the reinforcing metal 45. The reinforcing metal 45 is connected to each cell holder 32 to reinforce the connecting portion of the battery block 33. The reinforcing metal 45 is disposed in the valley space 42 of the cell holder 32. The reinforcing metal 45 opens a connection hole 46 for connecting the cell holder 32. The reinforcing metal 45 has connecting holes 46 at positions where all the cell holders 32 are connected. Each cell holder 32 is integrally formed with a connection hook 47 that is inserted into the connection hole 46 and connected to the reinforcing metal 45. All cell holders 32 are provided with connecting hooks 47 so as to face the same direction. The reinforcing metal 45 is connected to the connecting hook 47 by inserting the connecting hook 47 of the cell holder 32 into the connecting hole 46 and shifting it in the longitudinal direction. In this state, a set screw 48 penetrating the reinforcing metal 45 is screwed into the cell holder 32 to fix the reinforcing metal 45 so as not to be displaced. In this structure, all the cell holders 32 can be connected in a straight line with one reinforcing metal 45. Further, the reinforcing metal 45 can be easily connected to all the cell holders 32 by shifting in the longitudinal direction.

  Further, the battery rod 54 of FIGS. 9 and 10 reinforces the connecting portion of the battery block 53 by screwing the reinforcing metal 65. In the cell holder 52 shown in these drawings, as shown in FIG. 11, a valley space 62 of the storage cylinder 58 is formed thick, and a female screw hole 69 into which a set screw 68 is screwed is provided. The cell holder 52 reinforces the connecting portion of the battery block 53 by screwing a set screw 68 penetrating the reinforcing metal 65 into the female screw hole 69. The reinforcing metal 65 shown in the figure is disposed between the adjacent cell holders 52 and both ends thereof are fixed to the adjacent cell holders 52 with set screws 68. The total number of reinforcing metals can be fixed to the battery rod by screwing a set screw penetrating the reinforcing metal into each cell holder.

  The cell holders 32 and 52 that connect the three storage cylinders 38 and 58 in a stacked state form three valley spaces 42 and 62. The cell holders 32 and 52 are reinforced by fixing the substrate holders 7 and 7 to one valley space 42 and 62 and fixing reinforcing metals 45 and 65 to the other one or two valley spaces 42 and 62. be able to.

  Each of the battery blocks 3, 33, and 53 connects the batteries 1 to be stored side by side in parallel with a connection metal plate 5. In the battery blocks 3, 33, 53, the connection metal plate 5A is disposed at both ends of the cell holders 2, 32, 52, and the battery 1 inserted into the storage cylinders 8, 38, 58 by the connection metal plate 5A is used. Connect in parallel. In the illustrated battery blocks 3, 33, 53, three batteries 1 are connected in parallel by a connecting metal plate 5A. The connecting metal plates 5A at both ends of the battery blocks 3, 33, 53 are welded to the end face electrodes of the battery 1 placed in the storage cylinders 8, 38, 58, and connect the batteries 1 in parallel.

  A connection metal plate 5B disposed between adjacent battery blocks 3, 33, 53 is shown in FIG. The connecting metal plate 5B connects the batteries 1 accommodated in parallel to the battery blocks 3, 33, 53 in parallel, and the batteries 1 accommodated in the adjacent battery blocks 3, 33, 53 and arranged linearly. Are connected in series. The connecting metal plate 5B is between the battery blocks 3, 33, 53 and connects the batteries 1 of the adjacent battery blocks 3, 33, 53 in series. The connection metal plate 5B is cut into a shape in which two connection metal plates 5B are connected by a bending line 5X. One connecting metal plate 5B is connected to the battery 1 of one battery block 3, 33, 53 arranged adjacent to the other, and the other connecting metal plate 5B is connected to the other battery block 3, The batteries 1 and 33 are connected to the battery 1. After the two connecting metal plates 5B are welded to the end face electrodes of the battery 1 of the battery blocks 3, 33, 53 arranged adjacent to each other, as shown in FIG. Two connecting metal plates 5B are stacked. Bending the two connection metal plates 5B into a stacked state, the two adjacent battery blocks 3, 33, 53 are linearly connected by the connection metal plate 5B and connected in series. The two connecting metal plates 5B to be laminated can be firmly fixed to each other by welding them.

  Furthermore, the connection metal plate 5 is provided with a connection portion 5 a that connects the end face electrode of the battery 1 to the circuit board 6 so as to protrude from the outer periphery. The connecting portion 5 a is connected to the circuit board 6, and the battery voltage of the battery block 3 is input to the circuit board 6.

  The circuit board 6 detects the voltage of the battery 1 housed in the battery block 3 to prevent the battery 1 from being overcharged or overdischarged. The battery pack shown in the figure detects the voltages of all the battery blocks 3 and prevents overcharge and overdischarge of the batteries 1 of the battery block 3. Since the battery block 3 connects the plurality of batteries 1 in parallel, the voltage of the battery block 3 is the battery voltage to be connected in parallel. The battery voltage of the battery block 3 varies with the remaining capacity of the battery 1. When the battery 1 is discharged and the remaining capacity decreases, and when the battery 1 is further discharged and overdischarged, the voltage of the battery block 3 decreases to the lowest voltage. For this reason, when the protection circuit mounted on the circuit board 6 detects that the voltage of any one of the battery blocks 3 is lowered to the minimum voltage, the discharge of the battery pack is stopped and the overdischarge of the battery 1 is prevented. Further, when the battery 1 is charged to increase the remaining capacity and further charged and overcharged, the voltage of the battery block 3 rises to the maximum voltage. For this reason, when the voltage of any one of the battery blocks 3 rises to the maximum voltage, the protection circuit of the circuit board 6 stops discharging the battery pack, and the battery 1 can be prevented from being overcharged.

  A protection circuit that detects the voltage of the battery block 3 and controls charging / discharging of the battery 1 is mounted on the circuit board 6. The circuit board 6 is housed in the board holder 7 and is disposed at a fixed position of the battery rod 4. As shown in FIGS. 4, 5, and 7 to 9, the substrate holder 7 is formed of a hard plastic in an elongated shape along the battery rods 4, 34, 54 and a shape having a peripheral wall around the battery rod 4. . The substrate holder 7 is fixed to the battery rods 4, 34, 54 that linearly connect the battery blocks 3, 33, 53 to reinforce them. Therefore, the substrate holder 7 has such a length that both ends can be connected to the battery blocks 3, 33, 53 located at both ends connected linearly. The illustrated substrate holder 7 is substantially equal to the total length of the battery rods 4, 34 and 54. However, if the substrate holder 7 protrudes from both ends of the battery rods 4, 34, 54, it is necessary to enlarge the outer case 9, so that the overall length of the substrate holder 7 is shorter than the battery rods 4, 34, 54.

  Further, the substrate holder 7 is provided with a recess 7A for guiding the connection portion 5a of the connection metal plate 5 connected to the battery blocks 3, 33, 53. In the illustrated battery pack, five battery blocks 3, 33, 53 are connected, so that recesses 7A are provided at four locations. The substrate holder 7 has a peripheral wall along the recess 7A provided on the outer periphery.

  Furthermore, the substrate holder 7 is integrally formed with a fixing portion 15 that is connected to the fixing boss 10 of the cell holder 2. The substrate holder 7 shown in FIGS. 2 to 5 is provided with a fixing portion 15 formed in a plate shape at the corner of a recess 7A provided on the outer peripheral edge. The fixing portion 15 has a through hole of the set screw 11. A set screw 11 is passed through the through hole, and the set screw 11 is screwed into the fixing boss 10 to fix the substrate holder 7 to the cell holder 2. The substrate holder 7 is fixed to all the battery blocks 3. In the illustrated battery pack, five battery blocks 3 are connected to form a battery rod 4, so that fixed portions 15 are provided at five locations on the substrate holder 7. The substrate holder 7 fixes the fixing portions 15 to the cell holders 2 of all the battery blocks 3. The substrate holder 7 is fixed to the valley space 12 of the stacked cell holder 2 by fixing the fixing portion 15 to the fixing boss 10 of the cell holder 2.

The above battery pack is assembled as follows.
(1) Cell holders 2, 32, 52 molded in two parts are ultrasonically welded and connected to an integral structure, and battery 1 is inserted into storage cylinders 8, 38, 58 of cell holders 2, 32, 52 To do. In this process, the battery 1 is inserted into the cell holders 2, 32, 52 divided into two, and the battery holder 1 connects the pair of cell holders 2, 32, 52 in place, and ultrasonically welds or bonds them. Can be connected.
(2) The connecting metal plate 5 is spot welded to the end face electrode of the battery 1 to be inserted into the storage cylinder 8 of the cell holder 2, 32, 52. The connecting metal plate 5B connected to the facing surfaces of the battery blocks 3, 33, 53 arranged adjacent to each other is spot-welded to the end face electrode of the battery 1 in a flat shape or in a state where the bent line 5X is bent at a right angle. Then, the bent line 5X is bent, the adjacent battery blocks 3, 33, 53 are linearly connected by the connecting metal plate 5B, and the battery 1 is connected in series. The battery blocks that are connected in a straight line can be connected so as not to be displaced by providing fitting irregularities that are attached to each other and connected to a fixed position on the contact surfaces of both surfaces of the cell holder. As shown in FIG. 11, the cell holder 52 is provided with a plurality of convex portions 59 as shown in FIG. 11, and the other abutting surface is provided with a concave portion for guiding the convex portions 59, although not shown. The convex portion 59 is fitted in the concave portion so as to be connected to a fixed position.
(3) Battery blocks 3, 33, 53 arranged adjacent to each other are connected to each other. The battery block 3 is connected by a set screw 14 penetrating a connecting rod 13 provided in the valley space 12, or the reinforcing metals 45 and 65 are fixedly connected to the valley spaces 42 and 62. In this state, the plurality of battery blocks 3, 33, 53 are linearly connected to form battery rods 4, 34, 54.
(4) The substrate holder 7 is fixed to the valley spaces 12, 42, 62 of the battery rods 4, 34, 54. The substrate holder 7 is fixed to the battery rods 4, 34, and 54 by screwing a set screw 11 into the fixing boss 10 of the cell holders 2, 32, and 52 so as to penetrate the fixing portion 15.
(5) The circuit board 6 is housed in the board holder 7 and fixed in place. The connecting portions 5a of the connecting metal plate 5 connected to both ends of the battery blocks 3, 33, 53 are connected to the circuit board 6 by a method such as soldering to form a battery assembly. Thereafter, the substrate holder 7 is filled with an insulating resin, and the circuit board 6 is potted and embedded in the substrate holder 7. However, it is not always necessary to pot the insulating resin on the substrate holder.
(6) The battery assembly in which the substrate holder 7 is connected to the battery rods 4, 34, 54 is stored in the outer case 9, and the outer case 9 is closed.

1 is a perspective view of a battery pack according to an embodiment of the present invention. It is the perspective view which removed the upper cover of the battery pack shown in FIG. It is the perspective view which removed the exterior case of the battery pack shown in FIG. It is a perspective view of the battery assembly of the battery pack shown in FIG. It is a cross-sectional perspective view of the battery pack shown in FIG. It is a perspective view of the battery rod of the battery pack shown in FIG. It is a perspective view of the battery assembly of the pack battery concerning the other Example of this invention. It is a disassembled perspective view which shows the connection structure of the battery rod shown in FIG. It is a disassembled front view of the battery assembly of the pack battery concerning the other Example of this invention. It is a perspective view of the battery rod of the battery pack shown in FIG. It is a cross-sectional perspective view of the battery rod shown in FIG. It is a top view which shows an example of a connection metal plate. It is a side view which shows the state which connects a battery with the connection metal plate shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery 2 ... Cell holder 3 ... Battery block 4 ... Battery rod 5 ... Connection metal plate 5A ... Connection metal plate
5B ... Connection metal plate
5X ... tangent line
5a ... Connection 6 ... Circuit board 7 ... Substrate holder 7A ... Recess 8 ... Storage cylinder 9 ... Exterior case 9A ... Upper lid 10 ... Fixing boss 11 ... Set screw 12 ... Valley space 13 ... Connecting rod 14 ... Set screw 15 ... Fixing part 32 ... Cell holder 33 ... Battery block 34 ... Battery rod 38 ... Storage cylinder 42 ... Valley space 45 ... Reinforcing metal 46 ... Connection hole 47 ... Connection hook 48 ... Set screw 52 ... Cell holder 53 ... Battery block 54 ... Battery rod 58 ... Storage cylinder 59 ... Convex part 62 ... Valley space 65 ... Reinforcing metal 68 ... Set screw 69 ... Female screw hole

Claims (5)

  A plurality of battery blocks (3), (33), (53) storing the battery (1) in cell holders (2), (32), (52), and cell holders (2), (32), Battery rods (4), (34) connected to the end face electrode of the battery (1) housed in (52) and connected to a plurality of battery blocks (3), (33), (53) in a straight line , (54) and the connection metal plate (5) for connecting the batteries (1) stored in the cell holders (2), (32), (52) in series, and this connection metal plate (5) A circuit board (6) arranged in parallel with the battery rods (4), (34), (54) connected in a straight line and connected to the connection metal plate (5), and this circuit board (6) is housed and arranged parallel to the battery rods (4), (34), (54), and the cell holders (2), (53) of the battery blocks (3), (33), (53) 32) A battery pack comprising a substrate holder (7) connecting (52).   Cell holders (8), (38) in which the cell holders (2), (32), (52) of the battery blocks (3), (33), (53) store a plurality of batteries (1) in a parallel posture , (58), and a plurality of batteries (1) stored in the storage cylinders (8), (38), (58) are connected in parallel by a connecting metal plate (5). The battery pack described.   The cell holders (8), (38) in which the cell holders (2), (32), (52) of the battery blocks (3), (33), (53) store three batteries (1) in a stacked state 3) A battery pack according to claim 2, wherein a substrate holder (7) is connected between valleys of the battery (1) arranged in a stacked state.   Fix the reinforcing metal (45), (65) to the side of the battery rod (34), (54), and reinforce the connecting part of the battery block (33), (53) with this reinforcing metal (45), (65) The battery pack according to claim 1. A connection hole (46) is opened in the reinforcing metal (45), and the cell holder (32) of the battery block (33) has a connection hook (47) to be inserted and connected to the connection hole (46). The battery pack according to claim 4, wherein the connecting hook (47) of the cell holder (32) is connected by being inserted into the connecting hole (46) of the reinforcing metal (45).

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