JP2014229457A - Power storage device and working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device mounting a voltage equalization device applicable even when the terminals of a power storage cell are arranged on both sides of the cell array of a power storage module.SOLUTION: A plurality of power storage cells are housed in a lower housing opening upward, and a housing having a lid closing the open part of the lower housing. At least one mounting board is housed in the housing. A plurality of voltage equalization circuits prepared corresponding to the plurality of power storage cells, and equalizing the voltage across the terminals of the plurality of power storage cells is mounted on the mounting board. A board side connector having an insertion port directed in the same direction as the open part of the lower housing, and connected with the voltage equalization circuit is mounted on the mounting board. A current path connects the power storage cell with the board side connector.

Description

  The present invention relates to a power storage device equipped with a voltage equalizing device that equalizes voltages between terminals of a plurality of power storage cells connected in series, and a work machine equipped with the power storage device.

  A power storage module configured by connecting a plurality of power storage cells in series is mounted on a hybrid work machine. For example, an electric double layer capacitor, a lithium ion capacitor, a lithium ion secondary battery, or the like is used for the storage cell. A voltage equalization circuit (balance circuit) that limits the inter-terminal voltage to a predetermined value or less is connected to the plurality of storage cells connected in series (Patent Document 1).

  The electricity storage cell disclosed in Patent Document 1 has a positive electrode terminal and a negative electrode terminal protruding upward. The plurality of power storage cells are arranged in a line. One board | substrate with which the wiring pattern was formed is arrange | positioned on a some electrical storage cell, and is attached to a positive electrode terminal and a negative electrode terminal. A plurality of power storage cells are connected in series by a wiring pattern formed on the substrate. A voltage equalization circuit is disposed between the positive terminal and the negative terminal of each storage cell.

  The discharge current flowing through the voltage equalization circuit increases as the voltage between the terminals of the storage cell increases. Furthermore, the discharge current increases as the temperature of the storage cell increases. Thereby, appropriate discharge according to the temperature of the electricity storage cell is possible, and the life of the electricity storage cell can be extended.

JP 202-42903 A

  In some cases, the positive electrode terminal and the negative electrode terminal are led out in opposite directions from positions opposite to each other on the edge of the plate-shaped storage cell. When this power storage cell is stacked in the thickness direction, a pair of terminals of each power storage cell are arranged on both sides with the cell row as the center. For this reason, one board | substrate cannot be connected to the positive electrode terminal and negative electrode terminal of a some electrical storage cell.

  The objective of this invention is providing the electrical storage apparatus which mounts the voltage equalization apparatus applicable also when the terminal of an electrical storage cell is arrange | positioned at the both sides of the cell row | line | column of an electrical storage module. Another object of the present invention is to provide a work machine equipped with this power storage device.

According to one aspect of the invention,
A lower housing that houses a plurality of storage cells and is opened upward; and a housing having a lid that closes an open portion of the lower housing;
At least one mounting substrate housed in the housing;
A plurality of voltage equalization circuits mounted on the mounting substrate, prepared corresponding to the plurality of storage cells, and equalizing voltages between terminals of the plurality of storage cells;
A board-side connector that is mounted on the mounting board, the insertion port faces in the same direction as the opening of the lower housing, and is connected to the voltage equalization circuit;
There is provided a power storage device having a current path connecting the power storage cell to the board-side connector.

According to another aspect of the invention,
A lower traveling body,
An upper revolving unit mounted on the lower traveling unit so as to be able to swivel;
A turning electric motor for turning the upper turning body;
A work machine having a power storage device for supplying electric power to the swing motor,
The power storage device
A lower housing that houses a plurality of storage cells and is opened upward; and a housing having a lid that closes an open portion of the lower housing;
At least one mounting substrate housed in the housing;
A plurality of voltage equalization circuits mounted on the mounting substrate, prepared corresponding to the plurality of storage cells, and equalizing voltages between terminals of the plurality of storage cells;
A board-side connector that is mounted on the mounting board, the insertion port faces in the same direction as the opening of the lower housing, and is connected to the voltage equalization circuit;
A work machine having a current path connecting the power storage cell to the board-side connector is provided.

  A mounting board on which a voltage equalization circuit is mounted is housed in a housing in which the storage cells are housed. For this reason, the freedom degree of arrangement | positioning with an electrical storage cell and a mounting board increases. In addition, since the insertion port of the board-side connector faces the same direction as the opening of the lower housing, the current path can be easily inserted into the board-side connector with the lid of the lower housing removed. High workability can be ensured.

1A is a perspective view of a voltage equalizing apparatus for a power storage module according to a first embodiment, and FIG. 1B is an exploded perspective view of a storage container. FIG. 2 is a plan view of the mounting substrate. FIG. 3 is a diagram showing a connection configuration of a plurality of power storage cells and thermistors connected in series and a cable-side connector. 4A is a plan cross-sectional view of a voltage equalizing apparatus for a power storage module according to the first embodiment, and FIG. 4B is a plan cross-sectional view of a voltage equalizing apparatus for a power storage module according to a modification of the first embodiment. 5A and 5B are perspective views of a lid and a lower housing of the power storage device according to the second embodiment, respectively. FIG. 6 is a plan view of the lower housing and the components mounted on the lower housing. 7A is a plan view of the power storage module, and FIG. 7B is a cross-sectional view taken along one-dot chain line L9B-L9B in FIG. 7A. 8 is a cross-sectional view taken along one-dot chain line L10-L10 in FIG. FIG. 9 is a side view of the shovel according to the third embodiment. FIG. 10 is a block diagram of an excavator according to the third embodiment.

[Example 1]
With reference to FIG. 1A-FIG. 4B, the voltage equalization apparatus for electrical storage modules by Example 1 is demonstrated.

FIG. 1A is a perspective view of a voltage equalizing apparatus for a storage module according to the first embodiment. The voltage equalization apparatus includes a plurality of mounting substrates 13 and a storage container 20 that stores the mounting substrates 13. A plurality of mounting boards 13 are stacked in the thickness direction. A plurality of board-side connectors 15 are mounted on each of the mounting boards 13. The storage container 20 has a cylindrical shape with square openings on the top and bottom. The two openings face the direction orthogonal to the stacking direction of the mounting substrate 13. Hereinafter, the stacking direction of the mounting substrate 13 may be simply referred to as “stacking direction”.

  The board-side connector 15 is attached at a position accessible through one opening. Specifically, the mounting board 13 is attached in the vicinity of an edge that faces the same direction (upward in FIG. 1A) as the direction in which one opening portion faces. The insertion port of the board-side connector 15 faces upward, and the cable-side connector is inserted into the board-side connector 15 from above.

  FIG. 1B shows an exploded perspective view of the storage container 20. The storage container 20 includes a first side member 21 and a second side member 22. One side surface 21 </ b> A orthogonal to the stacking direction and a pair of side surfaces 21 </ b> B parallel to the stacking direction are configured by the first side surface member 21. Another side surface 22 </ b> A perpendicular to the stacking direction is configured by the second side surface member 22.

  A pair of attachment portions 21C protrudes outward from the edge of the opening portion of the storage container 20 facing upward. Specifically, the attachment portion 21C is formed by bending the upper ends of a pair of side surfaces 21B parallel to the stacking direction by 90 ° outward.

  The overlapping portion 22 </ b> B is formed by bending both ends of the second side member 22 in the direction of the first side member 21. The overlapping portion 22 </ b> B overlaps a part of the side surface 21 </ b> B of the first side surface member 21. The second side member 22 is fixed to the first side member 21 by overlapping the through hole 23 formed in the side surface 21B and the through hole 24 formed in the overlapping portion 22B and tightening with a fastener. The

  One of the through hole 23 and the through hole 24 is a long hole that is long in the stacking direction. That is, one of the through hole 23 and the through hole 24 has a planar shape that is long in the stacking direction. Thereby, the space | interval of a pair of side surface 21A and 22A perpendicular | vertical with respect to a stacking direction can be finely adjusted.

  A plurality of through holes 25 are formed on the side surface 21A, and through holes 26 are formed at positions corresponding to the opposing side surface 22A. The through holes 25 and 26 are for attaching a support for supporting the mounting substrate 13. A through hole 27 is formed in the attachment portion 21C. The through hole 27 is for attaching the storage container 20 to the housing of the power storage device.

  FIG. 2 shows a plan view of the mounting substrate 13. A board-side connector 15 is attached in the vicinity of one edge of the mounting board 13. The board-side connectors 15 are fitted into the cable-side connectors 31, respectively. A plurality of voltage equalization circuits 14 are mounted on the mounting substrate 13. The voltage equalization circuit 14 is connected to each terminal of the board-side connector 15 via a wiring pattern 36 formed on the mounting board 13.

  A plurality of through holes 18 are formed in the mounting substrate 13. The through hole 18 is disposed at a position corresponding to the through holes 25 and 26 of the side surfaces 21A and 22A shown in FIG. 1B.

  FIG. 3 shows a connection configuration between the plurality of power storage cells 10 connected in series and the cable-side connector 31. A plurality of power storage cells 10 are connected in series. A pair of terminals of the electricity storage cell 10 is connected to the cable-side connector 31 by a cable 33.

Each of the storage cells 10 is connected to the voltage equalization circuit 14 (FIG. 2) via the cable 33 (current path), the cable side connector 31, and the board side connector 15 (FIG. 2). The voltage equalization circuit 14 equalizes the voltage between the terminals of the plurality of storage cells 10.

  FIG. 4A is a plan cross-sectional view of the voltage equalizing apparatus for a power storage module according to the first embodiment. A plurality of mounting boards 13 stacked in the thickness direction are stored in the storage container 20. A voltage equalizing circuit 14 is mounted on the mounting substrate 13. The support 40 fixes the plurality of mounting boards 13 in the storage container 20. The support tool 40 passes from the outer surface of the one side surface 21A through the through hole 25 of the side surface 21A, the through hole 18 of the mounting substrate 13, and the through hole 26 of the opposite side surface 22A, and the outer surface of the side surface 22A. Reach up to.

  The support 40 is provided between the side surface 21A of the first side member 21 and the mounting substrate 13, between the two mounting substrates 13 adjacent to each other, and the side surface 22A of the second side member 22 and the mounting substrate 13. Male-female spacers 41 respectively disposed between the two. The mounting substrate 13 is fixed to the storage container 20 by a male / female spacer 41 and bolts 42 and nuts 43 attached to both ends.

  A fastener 48 passes through the through hole 23 of the side surface 21B and the through hole 24 of the overlapping portion 22B, and fixes the first side member 21 and the second side member 22 to each other. Due to the tolerance of the dimensions of the male-female spacer 41, the distance between the one side surface 21A and the side surface 22A facing it varies. Since one of the through holes 23 and 24 is a long hole that is long in the stacking direction, this variation can be absorbed.

  FIG. 4B shows another configuration example of the support 40. In the configuration example shown in FIG. 4B, the support tool 40 includes a hollow spacer 45, a bolt (tie rod) 46, and a nut 47. The tie rod 46 extends from the outer surface of the one side surface 21A to the outer surface of the other side surface 22A through the through hole 25, the hollow spacer 45, the through hole 18 of the mounting substrate 13, and the through hole 26.

[Example 2]
5A and 5B are perspective views of the lid 60 and the lower housing 50 of the power storage device according to the second embodiment, respectively. As shown in FIG. 5B, the lower housing 50 includes a bottom surface 51 and side surfaces 52, and the upper portion of the lower housing 50 is open. The side surface 52 is disposed over the entire outer peripheral line of the bottom surface 51. The lid 60 shown in FIG. 5A closes the open part above the lower housing 50.

  Two power storage modules 53 are mounted on the bottom surface 51. An xyz orthogonal coordinate system in which a plane parallel to the bottom surface 51 is defined as an xy plane and a normal direction of the bottom surface 51 is defined as a z direction is defined. The direction in which the two power storage modules 53 are separated is the x direction. Each of the power storage modules 53 includes a plurality of power storage cells stacked in the y direction, and charges and discharges electrical energy. The detailed configuration of the power storage module 53 will be described later with reference to FIGS. 6, 7A, and 7B.

  A connector box 59 is provided on one side surface 52 perpendicular to the y direction. The space in the connector box 59 and the space in the lower housing 50 communicate with each other through the opening 58. The opening above the connector box 59 is closed with a connector plate on which connector terminals are arranged.

  A first rib 55, a second rib 56, and a third rib 57 for increasing rigidity are formed on the bottom surface 51. The first rib 55 is disposed between the two power storage modules 53 and extends in a direction intersecting the x direction (y direction). One end of the first rib 55 is continuous with the side surface 52 facing the connector box 59.

The second rib 56 is continuous with the first rib 55 at the end of the first rib 55 and extends in the x direction. The first rib 55 is connected to the center of the second rib 56. The third rib 57 extends in the y direction from both ends of the second rib 56 and reaches the side surface 52 where the connector box 59 is provided. The opening 58 is disposed between the locations where the two third ribs 57 are connected to the side surface 52.

  With reference to the bottom surface 51, the first rib 55, the second rib 56, and the third rib 57 are lower than the side surface 52. With the open portion of the lower housing 50 closed with the lid 60, between the first rib 55 and the lid 60, between the second rib 56 and the lid 60, and between the third rib 57 and the lid 60, A gap is formed between the two.

  The bottom surface 51, the side surface 52, the first rib 55, the second rib 56, the third rib 57, and the connector box 59 are integrally formed by a casting method. For example, aluminum is used as the material.

  The voltage equalizing device 70 is disposed between the third rib 57 and the side surface 52 parallel to the y direction. As the voltage equalizing apparatus 70, the voltage equalizing apparatus according to the first embodiment (FIGS. 1A to 4B) is used.

  FIG. 6 shows a plan view of the lower housing 50 and components mounted on the lower housing 50. Two power storage modules 53 are mounted apart in the x direction. The first rib 55 passes between the two power storage modules 53 in the y direction. One end of the first rib 55 is continuous with the side surface 52. The other end of the first rib 55 is located outside the end of the power storage module 53 in the y direction. From this end, the second rib 56 extends in the x direction. The second rib 56 partially overlaps each of the power storage modules 53 in the x direction. From both ends of the second rib 56, the third rib 57 extends in the y direction and reaches the side surface 52 on which the connector box 59 is provided.

  A pair of relay members 62 are arranged in a region surrounded by the second rib 56, the third rib 57, and the connector box 59. A relay circuit 63 is disposed in the connector box 59.

  Each of the power storage modules 53 includes a plurality of plate-shaped power storage cells 10. The plurality of power storage cells 10 are stacked in the thickness direction (y direction). Each of the energy storage cells 10 has a pair of terminals 11 led out in the x direction and in opposite directions. The plurality of power storage cells 10 are connected in series. The storage module 53 is charged and discharged through the terminals 11 at both ends of the series circuit of the plurality of storage cells 10. The terminals 11 at both ends far from the connector box 59 are electrically connected to each other. The pair of terminals 11 may be connected via a fuse.

  The terminals 11 at both ends closer to the connector box 59 are electrically connected to the relay member 62 by bus bars 65, respectively. The bus bar 65 intersects with the second rib 56. The relay member 62 is connected to the relay circuit 63 by the bus bar 66. The bus bar 66 passes through the opening 58 (FIG. 5B). A voltage equalizing device 70 is mounted between the third rib 57 and the side surface 52 parallel thereto. Each terminal 11 of the storage cell 10 is connected to the voltage equalizing apparatus 70 via the cable 33.

FIG. 7A shows a plan view of the power storage module 53. The plate-shaped storage cells 10 and the heat transfer plates 67 are alternately stacked in the thickness direction (y direction). One heat transfer plate 67 may be arranged for a plurality of, for example, two storage cells 10. A pair of terminals 11 are drawn from each of the storage cells 10. The terminal 11 passes through the outside of the heat transfer plate 67 and is connected to the terminal 11 of the adjacent storage cell 10.

  The pressurizing mechanism 80 applies a compressive force in the stacking direction to the stacked structure in which the storage cell 10 and the heat transfer plate 67 are stacked. The pressure mechanism 80 includes a pressure plate 81 disposed at both ends of the laminated structure and a plurality of tie rods 82 extending from one pressure plate 81 to the other pressure plate 81. By tightening the tie rod 82 with a nut, a compressive force in the stacking direction can be applied to the stacked structure of the storage cell 10 and the heat transfer plate 67.

  7B is a cross-sectional view taken along one-dot chain line L9B-L9B in FIG. 7A. A pressure plate 81 is screwed to the bottom surface 51 of the lower housing 50. The lower end of the heat transfer plate 67 is in contact with the bottom surface 51, and the upper end is in contact with the lid 60. The lid 60 is fastened and fixed to the lower housing 50 with a bolt or the like, and a compressive force in the z direction is applied to the heat transfer plate 67. Due to this compressive force, the power storage module 53 is firmly and non-slidably fixed in the housing composed of the lower housing 50 (FIG. 5B) and the lid 60 (FIG. 5A). Thereby, the reliability with respect to an impact or a vibration can be improved.

  A cooling medium channel 69 is formed in the bottom surface 51, and a cooling medium channel 64 is also formed in the lid 60. The storage medium 10 can be cooled via the heat transfer plate 67 by circulating a cooling medium, for example, water through the flow paths 64 and 69.

  FIG. 8 is a cross-sectional view taken along one-dot chain line L10-L10 in FIG. A third rib 57 rises upward from the bottom surface 51 of the lower housing 50. A step 83 is formed on the inner surface of the side surface 52. The step 83 is arranged at the same height as the upper end of the third rib 57. A voltage equalizing device 70 is disposed between the third rib 57 and the side surface 52. As the voltage equalizing apparatus 70, the voltage equalizing apparatus according to the first embodiment shown in FIGS. 1A to 4B is used.

  The mounting substrate 13 is supported between the two side surfaces 21B. The voltage equalizing device 70 is in a position where the opening of the storage container 20 (FIG. 1A) and the insertion port of the board-side connector 15 face the same direction (upward) as the opening of the lower housing 50 faces. Arranged in the housing 50. Two attachment portions 21 </ b> C are supported by the step 83 and the upper surface of the third rib 57, respectively. The storage container 20 (FIGS. 1A and 1B) is fixed to the lower housing 50 by a fastener 85 (for example, a bolt) that passes through the through hole 27 (FIGS. 1A and 1B) formed in the attachment portion 21 </ b> C. The mounting substrate 13 is perpendicular to the stacking direction (y direction) of the storage cells 10.

  Since the opening of the storage container 20 (FIG. 1A) and the insertion openings of the board-side connectors 15 of all the mounting boards 13 face upward, the cable equalizing device 70 is fixed to the lower housing 50 and the cable The side connector 31 (FIG. 2) can be easily inserted into the board side connector 15. Thereby, the maintenance property is improved.

  Furthermore, as shown in FIG. 1A, the attachment portion 21C is provided at the edge of the upper opening. When an attachment portion is provided at the edge of the lower opening, and the storage container is screwed to the bottom surface 51 (FIG. 8) of the lower housing 50, it is screwed by avoiding the components housed in the lower housing 50. Must. For this reason, workability | operativity is bad. On the other hand, in Example 2, since the attaching part 21C is provided at the upper end of the side surface 21B, workability when attaching the storage container 20 (FIG. 1A, FIG. 1B) to the lower housing 50 can be improved. it can.

[Example 3]
FIG. 9 shows a side view of an excavator as an example of the work machine according to the third embodiment. An upper swing body 101 is mounted on the lower traveling body 100. A boom 103 is connected to the upper swing body 101, an arm 105 is connected to the boom 103, and a bucket 107 is connected to the arm 105. As the boom cylinder 104 expands and contracts, the posture of the boom 103 changes. As the arm cylinder 106 expands and contracts, the posture of the arm 105 changes. Due to the expansion and contraction of the bucket cylinder 108, the posture of the bucket 107 changes. The boom cylinder 104, the arm cylinder 106, and the bucket cylinder 108 are hydraulically driven. A swing motor 102, an engine 110, a motor generator 111, and a power storage device 115 are mounted on the upper swing body 101.

  FIG. 10 is a block diagram of a work machine according to the third embodiment. In FIG. 10, the mechanical power system is represented by a double line, the high-pressure hydraulic line is represented by a thick solid line, the electric control system is represented by a thin solid line, and the pilot line is represented by a broken line.

  The drive shaft of engine 110 is connected to the input shaft of torque transmission mechanism 121. The engine 110 is an engine that generates a driving force using fuel other than electricity, for example, an internal combustion engine such as a diesel engine.

  The drive shaft of the motor generator 111 is connected to the other input shaft of the torque transmission mechanism 121. The motor generator 111 can perform both the electric (assist) operation and the power generation operation. For the motor generator 111, for example, an internal magnet embedded (IPM) motor in which a magnet is embedded in the rotor is used.

  The torque transmission mechanism 121 has two input shafts and one output shaft. A drive shaft of the main pump 122 is connected to the output shaft.

  When the load applied to the main pump 122 is large, the motor generator 111 performs an assist operation, and the driving force of the motor generator 111 is transmitted to the main pump 122 via the torque transmission mechanism 121. Thereby, the load applied to the engine 110 is reduced. On the other hand, when the load applied to the main pump 122 is small, the driving force of the engine 110 is transmitted to the motor generator 111 via the torque transmission mechanism 121, so that the motor generator 111 is operated for power generation.

  The main pump 122 supplies hydraulic pressure to the control valve 124 via the high pressure hydraulic line 123. The control valve 124 distributes hydraulic pressure to the hydraulic motors 109 </ b> A and 109 </ b> B, the boom cylinder 104, the arm cylinder 106, and the bucket cylinder 108 according to a command from the driver. The hydraulic motors 109A and 109B drive two left and right crawlers provided in the lower traveling body 100 (FIG. 9), respectively.

  Motor generator 111 is connected to power storage circuit 112 via inverter 113A. The turning electric motor 102 is connected to the power storage circuit 112 via the inverter 113B. Inverters 113 </ b> A and 113 </ b> B and power storage circuit 112 are controlled by control device 135.

  Inverter 113 </ b> A controls operation of motor generator 111 based on a command from control device 135. Switching between the assist operation and the power generation operation of the motor generator 111 is performed by the inverter 113A.

  During the period in which the motor generator 111 is assisted, necessary power is supplied from the power storage circuit 112 to the motor generator 111 through the inverter 113A. During the period in which the motor generator 111 is generating, the electric power generated by the motor generator 111 is supplied to the power storage circuit 112 through the inverter 113A. Thereby, power storage device 115 in power storage circuit 112 is charged. The power storage device according to the second embodiment is used for the power storage device 115 in the power storage circuit 112.

The swing electric motor 102 is AC driven by the inverter 113B and can perform both the power running operation and the regenerative operation. For the swing electric motor 102, for example, an IPM motor is used. During the power running operation of the swing motor 102, electric power is supplied from the power storage circuit 112 to the swing motor 102 via the inverter 113B. The turning electric motor 102 turns the upper turning body 101 (FIG. 9) via the speed reducer 131. During the regenerative operation, the rotational motion of the upper swing body 101 is transmitted to the swing motor 102 via the speed reducer 131, so that the swing motor 102 generates regenerative power. The generated regenerative power is supplied to the power storage circuit 112 via the inverter 113B. Thereby, power storage device 115 in power storage circuit 112 is charged.

  The resolver 132 detects the position of the rotating shaft of the turning electric motor 102 in the rotation direction. The detection result of the resolver 132 is input to the control device 135. By detecting the position of the rotating shaft in the rotational direction before and after the operation of the turning electric motor 102, the turning angle and the turning direction are derived.

  A mechanical brake 133 is connected to the rotating shaft of the turning electric motor 102 and generates a mechanical braking force. The braking state and the release state of the mechanical brake 133 are controlled by the control device 135 and are switched by an electromagnetic switch.

  The pilot pump 125 generates a pilot pressure necessary for the hydraulic operation system. The generated pilot pressure is supplied to the operating device 128 via the pilot line 126. The operation device 128 includes a lever and a pedal and is operated by a driver. The operating device 128 converts the primary side hydraulic pressure supplied from the pilot line 126 into a secondary side hydraulic pressure in accordance with the operation of the driver. The secondary hydraulic pressure is transmitted to the control valve 124 via the hydraulic line 129 and also to the pressure sensor 127 via the other hydraulic line 130.

  The pressure detection result detected by the pressure sensor 127 is input to the control device 135. Thereby, the control apparatus 135 can detect the operation state of the lower traveling body 100, the turning electric motor 102, the boom 103, the arm 105, and the bucket 107 (FIG. 9).

  The upper swing body 101 of the work machine is more likely to vibrate during work and travel compared to a general transport vehicle. For this reason, the power storage device 115 mounted on the upper swing body 101 also vibrates and receives an impact. In the third embodiment, since the power storage device according to the second embodiment is used as the power storage device 115, high reliability against vibration and impact can be ensured.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

DESCRIPTION OF SYMBOLS 10 Storage cell 11 Terminal 12 Thermistor 13 Mounting board 14 Voltage equalization circuit 15 Board side connector 18 Through-hole 20 Storage container 21 1st side surface member 21A Side surface 21B orthogonal to the stacking direction Side surface 21C parallel to the stacking direction Two side members 22A Side 22B perpendicular to the stacking direction Overlapping portions 23, 24, 25, 26, 27 Through hole 31 Cable side connector 33, 35 Cable 36, 37 Wiring pattern 40 Support tool 41 Male female spacer 42 Bolt 43 Nut 45 hollow spacer 46 tie rod 47 nut 50 lower housing 51 bottom surface 52 side surface 53 power storage module 55 first rib 56 second rib 57 third rib 58 opening 59 connector box 60 lid 62 relay member 63 relay circuit 64 flow path 65 , 66 Busbar 67 Heat transfer 69 Flow path 70 Voltage equalizing device 80 Pressurizing mechanism 81 Pressurizing plate 82 Tie rod 83 Step 85 Fastener 100 Lower traveling body 101 Upper turning body 102 Turning electric motor 103 Boom 104 Boom cylinder 105 Arm 106 Arm cylinder 107 Bucket 108 Bucket cylinder 109A, 109B Hydraulic motor 110 Engine 111 Motor generator 112 Power storage circuit 113A, 113B Inverter 115 Power storage device 121 Torque transmission mechanism 122 Main pump 123 High pressure hydraulic line 124 Control valve 125 Pilot pump 126 Pilot line 127 Pressure sensor 128 Operating device 129, 130 Pilot line 131 Reducer 132 Resolver 133 Mechanical brake 135 Control device

Claims (12)

A lower housing that houses a plurality of storage cells and is opened upward; and a housing having a lid that closes an open portion of the lower housing;
At least one mounting substrate housed in the housing;
A plurality of voltage equalization circuits mounted on the mounting substrate, prepared corresponding to the plurality of storage cells, and equalizing voltages between terminals of the plurality of storage cells;
A board-side connector that is mounted on the mounting board, the insertion port faces in the same direction as the opening of the lower housing, and is connected to the voltage equalization circuit;
A power storage device having a current path connecting the power storage cell to the board-side connector. In the housing, a plurality of the mounting boards stacked in the thickness direction are stored,
The power storage device according to claim 1, further comprising a storage container that supports the plurality of mounting boards and is fixed to the lower housing.   The storage container has an opening portion that faces a direction orthogonal to a stacking direction in which a plurality of the mounting substrates are stacked, and the opening portion faces the same direction as the opening portion of the lower housing. Item 3. The power storage device according to Item 2. The storage container is
A side surface perpendicular to the stacking direction of the mounting substrate, and a first side member constituting a pair of side surfaces parallel to the stacking direction;
A second side member constituting another side surface orthogonal to the stacking direction of the mounting substrate;
The power storage device according to claim 2, further comprising a fastener that fixes the second side member to the first side member.   Each of the first side member and the second side member includes a through hole that is overlapped with each other and through which the fastener passes, and the through hole of the first side member and the second side surface The power storage device according to claim 4, wherein at least one of the through holes of the member has a planar shape that is long in a stacking direction of the mounting substrate. Furthermore, it has a support that penetrates the plurality of mounting substrates and fixes the mounting substrate to the storage container,
6. The power storage device according to claim 2, wherein the support includes a spacer that is disposed between the mounting boards adjacent to each other and fixes a distance between the mounting boards. A lower traveling body,
An upper revolving unit mounted on the lower traveling unit so as to be able to swivel;
A turning electric motor for turning the upper turning body;
A work machine having a power storage device for supplying electric power to the swing motor,
The power storage device
A lower housing that houses a plurality of storage cells and is opened upward; and a housing having a lid that closes an open portion of the lower housing;
At least one mounting substrate housed in the housing;
A plurality of voltage equalization circuits mounted on the mounting substrate, prepared corresponding to the plurality of storage cells, and equalizing voltages between terminals of the plurality of storage cells;
A board-side connector that is mounted on the mounting board, the insertion port faces in the same direction as the opening of the lower housing, and is connected to the voltage equalization circuit;
A work machine having a current path connecting the power storage cell to the board-side connector. In the housing, a plurality of the mounting boards stacked in the thickness direction are stored,
The work machine according to claim 7, wherein the power storage device further includes a storage container that supports the plurality of mounting substrates and is fixed to the lower housing.   The storage container has an opening portion that faces a direction orthogonal to a stacking direction in which a plurality of the mounting substrates are stacked, and the opening portion faces the same direction as the opening portion of the lower housing. Item 9. The work machine according to Item 8. The storage container is
A side surface perpendicular to the stacking direction of the mounting substrate, and a first side member constituting a pair of side surfaces parallel to the stacking direction;
A second side member constituting another side surface orthogonal to the stacking direction of the mounting substrate;
The work machine according to claim 8 or 9, comprising a fastener that fixes the second side member to the first side member.   Each of the first side member and the second side member includes a through hole that is overlapped with each other and through which the fastener passes, and the through hole of the first side member and the second side surface The work machine according to claim 10, wherein at least one of the through holes of the member has a planar shape that is long in a stacking direction of the mounting substrate. The power storage device further includes a support that passes through the plurality of mounting substrates and fixes the mounting substrate to the storage container.
The work machine according to claim 8, wherein the support includes a spacer that is disposed between the mounting boards adjacent to each other and fixes a distance between the mounting boards.

Images