JP2018101495A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack capable of mitigating a shock from the outside.SOLUTION: A battery pack 100 includes: a battery cell 150; a cell holder 120 holding the battery cell 150; and a lower case 110 housing the battery cell 150 therein and engaged to the cell holder 120. At least one of the cell holder 120 and the lower case 110 includes a shock-absorbing structure on a side to which a shock is applied to the battery cell 150.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an assembled battery.

  Conventionally, an assembled battery in which a plurality of batteries are housed in a member such as a housing is known. For example, Patent Document 1 discloses an assembled battery mounted on a vehicle such as an automobile.

JP 2014-013726 A

  When the assembled battery is mounted on a vehicle, it may receive an impact according to the vehicle condition from the outside. Excessive impact can damage the battery pack. In particular, it is desirable that the battery be made difficult to break.

  The objective of this invention made | formed in view of this viewpoint is providing the assembled battery which can relieve the impact from the outside.

In order to solve the above problem, the assembled battery according to the first aspect is:
A battery cell;
A cell holder for holding the battery cell;
A lower case that houses the battery cell and engages the cell holder;
At least one of the cell holder and the lower case includes an impact absorbing structure on a side on which an impact is applied to the battery cell.

  According to the assembled battery according to the first aspect, an external impact can be reduced.

It is an external appearance perspective view of the assembled battery which concerns on one Embodiment. It is a functional block diagram which shows the outline of the power supply system containing the assembled battery of FIG. It is a figure which shows arrangement | positioning of the battery cell accommodated in the assembled battery of FIG. It is a figure which shows the state in which the battery cell of FIG. 3 was accommodated in the lower case and the cell holder. It is a figure which shows the structure of the bus bar between cells. It is AA sectional drawing of FIG. It is a front view of the assembled battery with which the sensor board | substrate was attached. It is a figure which shows the assembled battery with which the BAT case and the auxiliary machine base 200 were attached. It is a figure which shows the assembled battery with which the relay, the MOS substrate, and the BMS board were attached. It is a figure which shows the structure of a BMS board | substrate. It is a disassembled perspective view of the assembled battery of FIG. It is a perspective view which shows the structural example of the back side of a lower case. It is the figure which looked at the example of FIG. 12 from the back side. It is sectional drawing which shows the example of schematic structure of the vehicle carrying the assembled battery which concerns on one Embodiment. It is sectional drawing which shows the schematic structural example of the vehicle which concerns on a comparative example.

  Hereinafter, an embodiment according to the present disclosure will be described with reference to the drawings. The drawings are schematic. The dimensions or ratios on the drawings do not necessarily match the actual ones. The depiction of each component in each drawing may be partially simplified.

  FIG. 1 is an external perspective view of an assembled battery 100 according to an embodiment. The assembled battery 100 includes an upper case 300, a lower case 110, a cell holder 120, a BAT case 500, and a gas exhaust pipe 600. The lower case 110 is also referred to as a storage case. The cell holder 120 is also called a holder. The assembled battery 100 has a substantially rectangular parallelepiped shape. The surface facing the positive direction of the X axis is also referred to as the first side surface of the battery pack 100. The surface facing the negative direction of the X axis is also referred to as the second side surface of the battery pack 100. The surface facing the positive direction of the Z axis is also referred to as the upper surface of the assembled battery 100. The surface facing the negative direction of the Z axis corresponding to the opposite side of the upper surface is also referred to as the bottom surface of the battery pack 100. The surface facing the negative direction of the Y axis is also referred to as the front surface of the battery pack 100. The surface facing the positive direction of the Y axis corresponding to the opposite side of the front surface is also referred to as the back surface of the battery pack 100. The names of the surfaces of the assembled battery 100 can be applied as names indicating the surfaces of the lower case 110, the cell holder 120, and the BAT case 500.

  The lower case 110, the cell holder 120, and the BAT case 500 are engaged with each other on the first side surface side by the engaging member 180. The lower case 110, the cell holder 120, and the BAT case 500 are engaged with each other also on the second side surface by the engaging member 180. A member in which the lower case 110, the cell holder 120, and the BAT case 500 are engaged is also referred to as a battery case. A battery cell 150 (see FIG. 3) described later is accommodated in the battery case.

  The lower case 110, the cell holder 120, and the BAT case 500 may be made of a resin such as PBT (Poly-Butylene Terephthalate).

  The upper case 300 has a recess 301 and a recess 302 in a part of the side where the upper surface and the first side face are connected. The upper case 300 has a recess 303 in a part of the side where the front surface and the upper surface are connected. The assembled battery 100 includes an SSG terminal 250, a LOAD terminal 260, and a GND terminal 270 in the recess 301, the recess 302, and the recess 303, respectively.

  The upper case 300 has an opening 304 on the first side surface. The assembled battery 100 includes a connector 310 in the opening 304.

  The upper case 300 may be made of a resin such as PBT (Poly-Butylene Terephthalate).

  The gas discharge pipe 600 allows the gas discharged from the battery cell 150 to pass through and discharges the gas to the outside of the battery case. The gas exhaust pipe 600 may be a metal tube, for example.

  In this embodiment, it is assumed that the assembled battery 100 is mounted and used in a vehicle such as a vehicle equipped with an internal combustion engine or a hybrid vehicle capable of traveling with the power of both the internal combustion engine and the electric motor. The assembled battery 100 may be mounted under a vehicle seat, for example. The assembled battery 100 may be mounted on a center console of a vehicle, for example. The assembled battery 100 is not limited to a vehicle, and may be used for other purposes.

  FIG. 2 is a functional block diagram showing an outline of a power supply system 400 including the assembled battery 100 shown in FIG. The power supply system 400 includes an assembled battery 100, an alternator 410, a starter 420, a second secondary battery 430, a load 440, a switch 450, and a control unit 460. The assembled battery 100 includes a first secondary battery 130 housed in the lower case 110. The first secondary battery 130, the alternator 410, the starter 420, the second secondary battery 430, and the load 440 are connected in parallel.

  The assembled battery 100 includes a MOSFET 210 (Metal Oxide Semiconductor Field Effect Transistor), a relay 220, and a sensor 230. The assembled battery 100 further includes a fusible link 240, a first secondary battery 130, and a BMS 140 (Battery Management System). The BMS 140 is also called a battery controller. The assembled battery 100 further includes an SSG terminal 250, a LOAD terminal 260, and a GND terminal 270.

  Relay 220, first secondary battery 130, fusible link 240, and GND terminal 270 are connected in series in this order. Relay 220 is electrically connected to MOSFET 210 and SSG terminal 250. The SSG terminal 250 is electrically connected to the alternator 410. MOSFET 210 is connected in series to second secondary battery 430 and load 440 through LOAD terminal 260. The GND terminal 270 is grounded.

  The sensor 230 is electrically connected to the first secondary battery 130. The BMS 140 is communicably connected to the sensor 230. The BMS 140 is communicably connected to the control unit 460 of the power supply system 400. The BMS 140 is communicably connected to the MOSFET 210, the relay 220, and the sensor 230. A circuit for executing the function of the sensor 230 is mounted on the sensor substrate 231 (see FIG. 7).

  The relay 220 functions as a switching element that connects or disconnects the first secondary battery 130 in parallel with each component outside the assembled battery 100 in the power supply system 400. Each component of the power supply system 400 outside the assembled battery 100 is also referred to as an external circuit.

  The sensor 230 has an appropriate structure, and measures the current flowing through the circuit including the first secondary battery 130 or the voltage applied to the circuit including the first secondary battery 130 by an appropriate method.

  The fusible link 240 includes a fuse body, a housing made of an insulating resin that accommodates and holds the fuse body, and a cover made of an insulating resin that covers the housing, and is blown when an overcurrent occurs.

  The first secondary battery 130 is configured by an assembly of battery cells 150 (see FIG. 3). The battery cell 150 constituting the first secondary battery 130 may be a secondary battery such as a lithium ion battery or a nickel metal hydride battery. The first secondary battery 130 is electrically connected to the relay 220 on the positive electrode side. The first secondary battery 130 is electrically connected to the fusible link 240 on the negative electrode side. The fusible link 240 is grounded via the GND terminal 270.

  The MOSFET 210 functions as a switching element that connects or disconnects the second secondary battery 430 and the load 440 in parallel with other components in the power supply system 400. The assembled battery 100 may not include the MOSFET 210. The MOSFET 210 is mounted on the MOS substrate 212 (see FIG. 9).

  The BMS 140 acquires measurement results such as the current or voltage of the first secondary battery 130 from the sensor 230. The BMS 140 estimates the state of the first secondary battery 130 based on the measurement result. The BMS 140 estimates the charging rate of the first secondary battery 130, for example. The charging rate is also referred to as SOC (State Of Charge). A circuit for executing the function of the BMS 140 is mounted on the BMS substrate 141 (see FIGS. 9 and 10).

  Alternator 410 is a generator and is mechanically connected to the engine of the vehicle. Alternator 410 generates power by driving the engine. The electric power generated by the alternator 410 by driving the engine can be supplied to the first secondary battery 130, the second secondary battery 430, and the load 440 after the output voltage is adjusted by a regulator. The alternator 410 can generate power by regeneration when the vehicle is decelerated or the like. The electric power regenerated by the alternator 410 can be used for charging the first secondary battery 130 and the second secondary battery 430.

  The starter 420 can be configured to include a cell motor, for example. The starter 420 receives power supply from at least one of the first secondary battery 130 and the second secondary battery 430 and starts the engine of the vehicle.

  The second secondary battery 430 can be composed of, for example, a lead storage battery. The second secondary battery 430 supplies power to the load 440.

  The load 440 can include, for example, an audio, an air conditioner, and a navigation system provided in the vehicle. The load 440 operates by consuming the supplied power. The load 440 operates by receiving power supply from the first secondary battery 130 while the engine driving is stopped, and operates by receiving power supply from the alternator 410 and the second secondary battery 430 while driving the engine.

  Switch 450 is connected in series with starter 420. The switch 450 functions as a switching element that connects or disconnects the starter 420 in parallel with other components.

  The control unit 460 controls the overall operation of the power supply system 400. The control unit 460 may be configured by, for example, an ECU (Electric Control Unit or Engine Control Unit) of the vehicle. The control unit 460 is communicably connected to the switch 450 and the BMS 140. The control unit 460 is communicably connected to the MOSFET 210 and the relay 220 via the BMS 140. The control unit 460 controls operations of the switch 450, the MOSFET 210, and the relay 220, respectively. The control unit 460 controls each component to supply power by the alternator 410, the first secondary battery 130 and the second secondary battery 430, and the first secondary battery 130 and the second secondary battery 430. The battery 430 is charged.

  FIG. 3 is a perspective view showing the arrangement of the battery cells 150 housed in the assembled battery 100. The assembled battery 100 according to the present embodiment accommodates five battery cells 150-1 to 150-5. The number of battery cells 150 accommodated in the assembled battery 100 is not limited to five. The number of battery cells 150 accommodated in the assembled battery 100 can be appropriately determined according to the maximum output of the battery cells 150 and the power consumed by a driven device such as a vehicle.

  The battery cell 150 has a substantially rectangular parallelepiped shape having six surfaces. Two of the six surfaces of the battery cell 150 have a larger area than the other four surfaces. Two surfaces having a relatively large area among the surfaces of the battery cell 150 are also referred to as flat surfaces. The battery cell 150 is disposed such that the flat surface is directed in the positive direction and the negative direction of the Z axis. In other words, the battery cell 150 is disposed such that the flat surface is substantially parallel to the upper surface and the bottom surface of the assembled battery 100.

  In the assembled battery 100 according to this embodiment, the battery cells 150 are stacked in the Z-axis direction in two stages and three stages. The battery cells 150 stacked in two stages are arranged on the positive side of the X axis. The battery cells 150 stacked in three stages are arranged on the negative side of the X axis. The number of battery cells 150 stacked may be appropriately changed according to the number of battery cells 150 accommodated in the assembled battery 100. Between the battery cells 150 to be stacked, an insulating sheet 155 (see FIG. 11) for insulating the battery cells 150 is disposed.

  The surface of the battery cell 150 on the negative direction side of the Y axis is also referred to as a cap surface 151. The battery cell 150 is disposed so that the cap surface 151 faces the front side of the battery pack 100. The battery cell 150 includes a positive electrode terminal 152, a negative electrode terminal 153, and a safety valve 154 on the cap surface 151. The cap surface 151 has a substantially rectangular shape having a long side and a short side. The positive terminal 152 and the negative terminal 153 are provided near both ends of the cap surface 151 in the long side direction. The positive terminal 152 and the negative terminal 153 are electrodes that output power from the battery cell 150. The positive electrode terminal 152 and the negative electrode terminal 153 are collectively referred to as an electrode terminal.

  The safety valve 154 is provided between the positive terminal 152 and the negative terminal 153. The safety valve 154 is opened to discharge the gas to the outside when the pressure generated in the battery cell 150 causes the pressure inside the battery cell 150 to exceed a predetermined pressure. The pressure inside the battery cell 150 can be equal to or higher than a predetermined pressure when the battery cell 150 has deteriorated over time or has run out of heat. The predetermined pressure can be appropriately determined according to the specifications of the battery cell 150.

  FIG. 4 is a diagram illustrating a state in which the battery cell 150 is accommodated in the lower case 110 and the cell holder 120. The lower case 110 has an engagement hole 115 on the upper surface side. The lower case 110 also has an engagement hole 115 on the side of the bottom surface not shown. The cell holder 120 has an engaging claw 128 on the upper surface side. The cell holder 120 also has an engaging claw 128 on the side of the bottom surface not shown. The engagement hole 115 and the engagement claw 128 are engaged with each other on the upper surface side and the bottom surface side to engage the lower case 110 and the cell holder 120.

  In FIG. 4, the lower case 110 and the cell holder 120 are configured such that the engagement holes 115 are located outside the engagement claws 128. The lower case 110 and the cell holder 120 may be configured such that the engagement hole 115 is located inside the engagement claw 128. The engagement hole 115 and the engagement claw 128 may be exchanged. That is, the lower case 110 and the cell holder 120 may be configured such that the engagement hole 115 is provided in the cell holder 120 and the engagement claw 128 is provided in the lower case 110.

  The assembled battery 100 includes an engagement member 180 on the first side surface side. The assembled battery 100 also includes an engagement member 180 on the second side surface (not shown). The lower case 110 and the cell holder 120 each have a convex portion 112 and a convex portion 122 on the first side surface side. Each of the lower case 110 and the cell holder 120 has a convex portion 112 and a convex portion 122 on the second side surface (not shown). The engaging member 180 engages the lower case 110 and the cell holder 120 by sandwiching the convex 112 and the convex 122. The engaging member 180 may be an elastic member such as a clip.

  The cell holder 120 has an engagement hole 125 for engaging with the BAT case 500 on the upper surface side. The cell holder 120 also has an engagement hole 125 on the bottom surface (not shown).

  The assembled battery 100 includes inter-cell bus bars 160-1 to 160-4, a total positive terminal bus bar 164, and a total negative terminal bus bar 165 on the cell holder 120 side. The inter-cell bus bars 160-1 to 160-4 are collectively referred to as inter-cell bus bars 160. The inter-cell bus bar 160, the total plus terminal bus bar 164, and the total minus terminal bus bar 165 are collectively referred to as a bus bar. The bus bar is electrically connected to the electrode terminal of the battery cell 150. The bus bar may be welded to the electrode terminal of the battery cell 150. The bus bar may be electrically connected to the electrode terminal of the battery cell 150 by other methods such as crimping.

  The inter-cell bus bar 160 electrically connects the positive terminal 152 of the battery cell 150 and the negative terminal 153 of another battery cell 150. For example, the inter-cell bus bar 160-1 electrically connects the positive terminal 152 of the battery cell 150-1 and the negative terminal 153 of the battery cell 150-2. The inter-cell bus bar 160-4 electrically connects the positive terminal 152 of the battery cell 150-4 and the negative terminal 153 of the battery cell 150-5. The inter-cell bus bars 160-2 and 3 electrically connect the electrode terminals of the battery cells 150, similarly to the other inter-cell bus bars 160. The total positive terminal bus bar 164 is electrically connected to the positive terminal 152 of the battery cell 150-5. The total minus terminal bus bar 165 is electrically connected to the negative terminal 153 of the battery cell 150-1. The bus bar connects the battery cells 150 in series between the total positive terminal bus bar 164 and the total negative terminal bus bar 165.

  FIG. 5 is a diagram showing the structure of the inter-cell bus bar 160. The inter-cell bus bar 160 includes a convex portion 161, a terminal connection portion 162, and a sensor attachment terminal 163. The inter-cell bus bar 160 may be made of a conductive metal such as copper or aluminum.

  The convex portion 161 of the inter-cell bus bar 160 is provided in order to avoid contact with a structure such as a rib provided on the cell holder 120. The terminal connection part 162 is electrically connected to the electrode terminal of the battery cell 150. The convex portion 161 is located between the two terminal connection portions 162. For example, in FIG. 4, when the inter-cell bus bar 160-1 is viewed from the positive direction of the X axis, the convex portion 161 protrudes in the negative direction of the Y axis from the two terminal connection portions 162.

  The terminal connection part 162 has a welding opening 162a. The terminal connecting portion 162 is electrically connected to each electrode terminal of the battery cell 150 by welding such as bead welding at the peripheral edge of the welding opening 162a.

  The sensor attachment terminal 163 is a terminal to which the sensor substrate 231 (see FIG. 7) is attached. The sensor attachment terminal 163 has a nut 163a. The sensor substrate 231 is attached to the sensor attachment terminal 163 by, for example, a bolt that is screwed into the nut 163a. The sensor substrate 231 is electrically connected to the electrode terminal of each battery cell 150.

  As shown in FIG. 4, the total positive terminal bus bar 164 and the total negative terminal bus bar 165 include an external connection unit 166 and a terminal connection unit 162 similar to the inter-cell bus bar 160. Similar to the inter-cell bus bar 160, the total plus terminal bus bar 164 and the total minus terminal bus bar 165 may be made of a conductive metal such as copper or aluminum. The total plus terminal bus bar 164 and the total minus terminal bus bar 165 are electrically connected to the electrode terminals of the battery cell 150 by welding or the like at the peripheral edge portion of the welding opening 162a of the terminal connection portion 162.

  The total plus terminal bus bar 164 and the total minus terminal bus bar 165 are electrically connected to the total plus copper bus bar 285 and the total minus copper bus bar 286 (see FIGS. 8 and 9), respectively, by the external connection portion 166. The total plus copper bus bar 285 and the total minus copper bus bar 286 are also referred to as copper bus bars. The external connection part 166 has a screw hole 166a. The external connection portion 166 is electrically connected to the copper bus bar by a bolt or the like inserted into the screw hole 166a. The terminal connection portions 162 of the total plus terminal bus bar 164 and the total minus terminal bus bar 165 have sensor mounting terminals 163, similar to the inter-cell bus bar 160. The sensor board 231 is electrically connected to the total plus terminal bus bar 164 and the total minus terminal bus bar 165 via the sensor mounting terminal 163.

  As shown in FIG. 4, the assembled battery 100 includes a fastening portion 370 in the lower case 110. The fastening portion 370 is used to attach the auxiliary machine base 200 (see FIG. 8).

  As shown in FIG. 4, the assembled battery 100 includes safety valve covers 610 and 611 and a gas tube 620 on the front side. The safety valve covers 610 and 611 may be made of a resin such as PBT, for example. The safety valve covers 610 and 611 are attached to the cap surface 151 so as to cover the safety valve 154 with a seal 630 (see FIG. 11) sandwiched between the cap surface 151 of the battery cell 150. The seal 630 may be made of rubber such as EPDM (Ethylene-Propylene-Diene Monomer). The safety valve covers 610 and 611 may be attached to the cell holder 120 by screwing or the like.

  The safety valve cover 610 is attached in common to the safety valves 154 of the battery cells 150-1 to 150-3 stacked in three stages. The safety valve cover 611 is attached in common to the safety valves 154 of the battery cells 150-4 to 5 stacked in two stages. The safety valve covers 610 and 611 can hold the gas discharged from the safety valve 154 of the battery cell 150 inside.

  The safety valve cover 610 has a gas duct 612 that allows the gas discharged from the safety valve 154 to pass therethrough. The gas duct 612 protrudes from the safety valve cover 610 to the front side of the assembled battery 100. The safety valve cover 611 includes gas ducts 613 and 614 that allow the gas discharged from the safety valve 154 to pass therethrough. The gas ducts 613 and 614 protrude from the safety valve cover 611 to the front side of the assembled battery 100.

  The gas duct 612 of the safety valve cover 610 and the gas duct 613 of the safety valve cover 611 are connected by a gas tube 620 so that gas does not leak. In this case, the gas discharged from the battery cells 150-1 to 150-3 to the safety valve cover 610 can move to the safety valve cover 611.

  The gas duct 614 of the safety valve cover 611 is connected to the gas exhaust pipe 600 so that the gas does not leak. In this case, the gas moved from the safety valve cover 610 to the safety valve cover 611 and the gas discharged from the battery cells 150-4 to 5 to the safety valve cover 611 can be discharged to the gas discharge pipe 600. When the assembled battery 100 is mounted on a vehicle, the gas discharge pipe 600 discharges gas to an external space below the vehicle body, for example.

  By connecting the safety valve covers 610 and 611 to the gas exhaust pipe 600 so that the gas does not leak, it becomes difficult for the gas to leak around the assembled battery 100. When the assembled battery 100 is mounted on a vehicle, the gas is discharged outside the vehicle and is difficult to leak into the vehicle. Since the gas ducts 612 and 614 protrude toward the front side of the assembled battery 100, the gas discharged from the battery cell 150 is easily guided toward the gas ducts 612 and 614.

  6 is a cross-sectional view taken along the line AA in FIG. In FIG. 6, the safety valve cover 610 and the bus bar are omitted. The battery cells 150-1 to 150-3 are stacked in three stages with the insulating sheet 155 interposed therebetween, and are accommodated between the lower case 110 and the cell holder 120. The lower case 110 includes a crushable zone 113 having ribs 114 on the positive direction side of the Y axis. The battery zone 150 is not accommodated in the crashable zone 113. The rigidity of the crushable zone 113 can be increased by the rib 114. The crushable zone 113 has a space in a portion other than the rib 114. By doing so, the crushable zone 113 is easily deformed so as to absorb the impact when, for example, an impact is applied to the lower case 110 in the negative direction of the Y axis. As a result, the impact on the battery cell 150 can be reduced. Further, the lower case 110 can be reduced in weight.

  FIG. 7 is a front view of the assembled battery 100 to which the sensor substrate 231 is attached. A description of the configuration shown in FIG. 4 is omitted. The assembled battery 100 includes sensor substrates 231-1 and 2 and FPCs 232-1 and 2 (Flexible Print Circuit) on the front side. The sensor substrates 231-1 and 231-2 are also referred to as sensor substrates 231. The FPC 232-1 and 2 are also referred to as FPC232.

  The sensor board 231-1 is attached to the sensor mounting terminals 163 of the inter-cell bus bars 160-1 to 160-3 and the total minus terminal bus bar 165 that are electrically connected to the battery cells 150-1 to 3-3 stacked in three stages. 233 is attached. The sensor substrate 231-2 is electrically connected to the sensor mounting terminals 163 of the inter-cell bus bars 160-3 to 4-4 and the total plus terminal bus bar 164 which are electrically connected to the battery cells 150-4 to 5 stacked in two stages. It attaches with the attachment member 233 so that it may connect. The attachment member 233 may be, for example, a screw or a screw. The FPC 232-1 electrically connects the sensor substrate 231-1 and the BMS substrate 141 (see FIGS. 9 and 10). The BMS substrate 141 includes a circuit that performs the function of the BMS 140 of FIG. The FPC 232-2 electrically connects the sensor board 231-1 and the sensor board 231-2.

  The sensor substrate 231 includes a circuit that performs the function of the sensor 230 of FIG. The sensor substrate 231 can measure at least one of a current flowing between the electrode terminals of each battery cell 150 and a voltage between the electrode terminals. The sensor substrate 231 may measure current or voltage in response to a measurement instruction from the BMS substrate 141. The sensor substrate 231 may output the measurement result to the BMS substrate 141.

  According to the assembled battery 100 according to the present embodiment, compared to a case where one sensor substrate 231 is attached across the battery cells 150 stacked in three stages and the battery cells 150 stacked in two stages, The stress applied to the sensor substrate 231 can be relaxed. According to the assembled battery 100 according to the present embodiment, the stress applied to the BMS substrate 141 can be relaxed compared to the case where the BMS substrate 141 is directly attached to the battery cell 150.

  FIG. 8 is a view showing the assembled battery 100 to which the BAT case 500 and the auxiliary machine base 200 are attached. The BAT case 500 is engaged with the cell holder 120. Each of the cell holder 120 and the BAT case 500 has a convex portion 122 and a convex portion 502 on the first side surface side. Each of the cell holder 120 and the BAT case 500 has a convex portion 122 and a convex portion 502 on the second side surface (not shown). The engaging member 180 engages the cell holder 120 and the BAT case 500 by sandwiching the convex portion 122 and the convex portion 502 between the first side surface and the second side surface.

  The BAT case 500 has claws that fit into the engagement holes 125 of the cell holder 120 shown in FIG. 4 on the upper surface side and the bottom surface side. The BAT case 500 and the cell holder 120 are also engaged when the engagement holes 125 of the cell holder 120 and the claws of the BAT case 500 are fitted on the upper surface and the bottom surface, respectively. The engagement hole 125 of the cell holder 120 may be located outside the claw of the BAT case 500 or may be located inside. The claw of the BAT case 500 and the engagement hole 125 of the cell holder 120 may be exchanged.

  By engaging the BAT case 500 with the cell holder 120, the configuration of the sensor substrate 231 provided on the cap surface 151 side of the battery cell 150 is covered by the BAT case 500. The BAT case 500 can mitigate the impact applied to the assembled battery 100 from the front side.

  A module configured by engaging the lower case 110, the cell holder 120, and the BAT case 500 is also referred to as a battery module. The battery module has a side where the battery cells 150 are stacked in three stages and a side where the battery cells 150 are stacked in two stages. The side where the battery cells 150 are stacked in three stages is also referred to as a three-stage side. The side where the battery cells 150 are stacked in two stages is also referred to as a two-stage side. In other words, the battery module has a two-stage side and a three-stage side. The lower case 110, the cell holder 120, and the BAT case 500 have a two-stage side and a three-stage side, similarly to the battery module.

  The BAT case 500 includes a fusible link 240 on the upper surface on the third stage side. The fusible link 240 is electrically connected at one end to the negative terminal 153 of the battery cell 150-1 via the total minus copper bus bar 286 and the total minus terminal bus bar 165. The fusible link 240 is electrically connected to the GND terminal 270 via the GND copper bus bar 280 at the other end.

  The lower case 110 has a nut hole 146 for attaching the BMS board 141 and a pin 147 for fitting into a fitting hole 144 (see FIG. 10) provided in the BMS board 141 on the upper surface of the battery module on the three-stage side. With. The lower case 110 includes a rib 114 on the back side of the assembled battery 100. The lower case 110 includes a fixing portion 116 on the back side of the assembled battery 100. The assembled battery 100 can be fixed to a vehicle body or the like by fixing the fixing portion 116 with a bolt or the like. The lower case 110 includes a pillar 117 extending from the fixed portion 116 to the upper surface side. The pillar 117 is thicker than other parts of the lower case 110 and may have high rigidity. The lower case 110 is less likely to be deformed by an external force applied to the fixing portion 116 because the pillar 117 has high rigidity.

  The auxiliary machine base 200 is fastened to the fastening portion 370 with bolts 340. Fastening portions 370 are provided at four locations on the upper surface of the battery module on the second stage side. The assembled battery 100 can be reduced in dimension in the Z-axis direction as compared with the case where the fastening portion 370 is provided on the upper surface of the battery module on the third stage side. The place where the fastening portion 370 of the auxiliary machine base 200 is provided is not limited to four places, and may be three places or less, or five places or more. The auxiliary machine base 200 can be more stably attached to the battery module by being fastened to the battery module by at least three fastening portions 370.

  The auxiliary machine base 200 illustrated in FIG. 8 includes a fastening portion 370 provided at at least one place on the upper surface of the second stage side of the BAT case 500 and a fastening provided at at least one place on the upper face of the second stage side of the lower case 110. Fastened to the part 370 with a bolt 340. In other words, the auxiliary machine base 200 illustrated in FIG. 8 is fastened over the entire battery module. When the auxiliary machine pedestal 200 is fastened over the entire battery module, for example, the rigidity of the battery module can be increased as compared with the case where the auxiliary machine pedestal 200 is fastened only to the lower case 110.

  The rigidity of the battery module can be increased by restricting relative displacement among the lower case 110, the cell holder 120, and the BAT case 500. When the auxiliary machine base 200 is fastened across the entire battery module, the relative displacement among the lower case 110, the cell holder 120, and the BAT case 500 can be restricted. Auxiliary machine base 200 is not only fastened across the entire battery module, but also fastened to the battery module so that relative displacement between lower case 110, cell holder 120, and BAT case 500 is restricted. Good. The auxiliary machine pedestal 200 may be fastened to at least one place of the upper case 300, for example. When the upper case 300 is assembled to the outside of the battery module, the relative displacement of each component of the battery module can be regulated by fastening at least one of the auxiliary machine base 200 and the upper case 300.

  In FIG. 8, the cell holder 120 has a convex portion 122 engaged with the lower case 110 and a convex portion 122 engaged with the BAT case 500 on the first side surface side. The convex part 122 engaged with the convex part 112 of the lower case 110 and the convex part 122 engaged with the convex part 502 of the BAT case 500 may be integrally formed. Similarly, the convex portion 122 may be formed integrally on the second side surface side. When the convex portion 122 is integrally formed, one engaging member 180 collectively holds the convex portion 112, the convex portion 122, and the convex portion 502 on each of the first side surface and the second side surface. Then, each component of the battery module may be engaged. When each component of the battery module is engaged by one engaging member 180 on each of the first side surface and the second side surface, the relative displacement of each component of the battery module can be more strongly regulated. The rigidity of the battery module can be increased by restricting the relative displacement of each component of the battery module.

  The rigidity of the battery module can be increased by restricting the relative displacement of each component of the battery module. Moreover, the rigidity of a battery module can be improved by fastening the auxiliary machine base 200 over the whole battery module. When the auxiliary machine base 200 fastened to the battery module or the relay 220 is fastened to the battery module, the rigidity of the battery module is increased, so that vibration due to the operation of the relay 220 hardly propagates to the surroundings. In this case, noise due to the operation of the relay 220 can be reduced.

  The auxiliary machine base 200 includes a relay fastening portion 360 for attaching the relay 220. The number of relay fastening portions 360 is not limited to three illustrated in FIG. 8, and may be two or less, or may be four or more. The thickness of the portion including the relay fastening portion 360 of the auxiliary machine pedestal 200 may be made thicker than the thickness of other parts of the auxiliary machine pedestal 200. By doing in this way, the rigidity of the part in which the relay 220 is attached can be improved. Further, vibration due to the operation of the relay 220 is difficult to propagate to the surroundings.

  FIG. 9 is a diagram showing the assembled battery 100 to which the relay 220, the MOS substrate 212, and the BMS substrate 141 are attached. Description of the configuration shown in FIG. 8 is omitted.

  The MOSFET 210 is mounted on the MOS substrate 212. The MOS substrate 212 is attached to the auxiliary machine base 200. The MOS substrate 212 is electrically connected to the LOAD terminal 260 via the LOAD copper bus bar 282.

  The relay 220 is fastened by a bolt 350 to a relay fastening portion 360 (see FIG. 8) provided on the auxiliary machine base 200. The location where the relay 220 is fastened is not limited to 3 locations, and may be 2 locations or less, or 4 locations or more. The relay 220 can be more stably attached to the auxiliary machine base 200 when fastened to the auxiliary machine base 200 at at least three locations.

  The relay 220 is electrically connected at one end to the positive terminal 152 of the battery cell 150-5 via the total plus copper bus bar 285 and the total plus terminal bus bar 164. Relay 220 is electrically connected to SSG terminal 250 and MOS substrate 212 via SSG copper bus bar 281 at the other end.

  FIG. 10 is a diagram showing the configuration of the BMS substrate 141. The BMS substrate 141 includes a circuit component 142, a mounting hole 143, and a fitting hole 144. At least a part of the circuit component 142 corresponds to a circuit that executes the function of the BMS 140. A nut hole 146 and a pin 147 are provided on the upper surface of the lower case 110 on the three-stage side. The BMS substrate 141 is attached to the nut hole 146 by the attachment member 145 so that the pin 147 and the fitting hole 144 are fitted. The attachment member 145 may be, for example, a screw or a screw. By fitting the pins 147 and the fitting holes 144, the accuracy of attaching the BMS substrate 141 to the battery module can be improved. Further, the BMS substrate 141 can be easily attached to the battery module.

  The BMS board 141 is communicably connected to the sensor board 231 by the FPC 232-1. The BMS substrate 141 is communicably connected to the MOS substrate 212 by the MOS cable 312. The BMS board 141 is communicably connected to the connector 310 by a connector cable 314. The BMS board 141 can be communicably connected to the control unit 460 of the power supply system 400 via the connector 310. The BMS substrate 141 is not limited to the control unit 460, and may be connected to other devices so as to be communicable.

  A module constituted by the auxiliary machine base 200, the relay 220, the MOS board 212, and the BMS board 141 is also referred to as an auxiliary machine module.

  FIG. 11 is an exploded perspective view of the battery pack 100 shown in FIG. The battery module may be assembled as follows. The battery cells 150 are stacked in three and two stages with the insulating sheet 155 interposed therebetween, and are accommodated between the lower case 110 and the cell holder 120. Lower case 110 and cell holder 120 are engaged by engagement member 180. A bus bar is attached to the electrode terminal of the battery cell 150. Safety valve covers 610 and 611 are attached to the cap surface 151 side of the battery cell 150 with the seal 630 interposed therebetween. Safety valve covers 610 and 611 are connected by a gas tube 620. The sensor substrate 231 is attached to the sensor attachment terminal 163 of the bus bar. The BAT case 500 is engaged with the cell holder 120 by the engaging member 180 so as to cover the cap surface 151 side of the battery cell 150. A gas exhaust pipe 600 is attached to the gas duct 614 of the safety valve cover 611. On the upper surface of the BAT case 500, a GND copper bus bar 280, a total minus copper bus bar 286, and a fusible link 240 are attached.

  The accessory module may be assembled as follows. The auxiliary machine base 200 is attached to the upper surface of the battery module on the second stage side with bolts 340. On the auxiliary machine base 200, the SSG copper bus bar 281, the LOAD copper bus bar 282, the total plus copper bus bar 285, and the MOS substrate 212 are attached. The relay 220 is attached to the auxiliary machine base 200 with bolts 350. The BMS substrate 141 is attached to the upper surface on the third stage side of the battery module. The auxiliary machine base 200 may be attached to the battery module after the relay 220 or the like is attached. When the relay 220 or the MOS substrate 212 is attached to the auxiliary machine base 200 before the auxiliary machine base 200 is attached to the battery module, the assembled battery 100 can be assembled more easily.

  The upper case 300 is attached so as to cover the whole after the battery module and the auxiliary module are combined. The upper case 300 may be engaged with the battery case, for example, by fitting a claw and a hole. The assembled battery 100 can be assembled according to the procedure example described above.

  In the assembly of the battery module, the battery cell 150 may be bonded to the cell holder 120 with an adhesive. The adhesive may be any adhesive that can bond the battery cell 150 and the cell holder 120. The adhesive may be, for example, an acrylic adhesive or an epoxy adhesive. The adhesive may be applied to the cell holder 120. The adhesive may be applied to a portion of the cell holder 120 that faces the cap surface 151 of the battery cell 150. The battery cell 150 may be inserted into the cell holder 120 after an adhesive is applied to the cell holder 120.

  After the battery cell 150 and the cell holder 120 are bonded, a bus bar may be welded to the electrode terminal of the battery cell 150. When the electrode terminal and the bus bar are welded, a high accuracy may be required for the positional relationship between the electrode terminal and the bus bar. In this case, welding of the electrode terminal and the bus bar can be facilitated by increasing the accuracy of the application position of the adhesive that bonds the battery cell 150 and the cell holder 120. Further, the battery cell 150 and the cell holder 120 are bonded to each other before the bus bar is welded to the battery cell 150, so that the productivity of the battery module can be improved.

  In the present embodiment, the battery module and the auxiliary machine module can be assembled separately. By doing in this way, the productivity of a battery module, an auxiliary machine module, and the assembled battery 100 can be improved.

  In the present embodiment, the assembled battery 100 includes the SSG terminal 250 and the LOAD terminal 260 on the first side surface, and includes the GND terminal 270 on the front surface side. The GND terminal 270 is easily identified by being disposed on a surface different from the surface on which the SSG terminal 250 and the LOAD terminal 260 are disposed. The assembled battery 100 includes a connector 310 on the first side surface side. The GND terminal 270 is easily identified by being arranged on a different side from the connector 310. By doing in this way, it becomes easy to prevent the incorrect wiring at the time of mounting the assembled battery 100 in a vehicle.

  The length of the cable electrically connected to the GND terminal 270 may be different from the length of the cable electrically connected to the SSG terminal 250 and the LOAD terminal 260. By doing in this way, it becomes easy to prevent the incorrect wiring at the time of mounting the assembled battery 100 in a vehicle.

  FIG. 12 is a perspective view showing a structural example on the back side of the lower case 110. FIG. 13 is a view of the example of FIG. 12 as seen from the back side. The lower case 110 includes a crushable zone 113, a fixing portion 116, and a pillar 117 on the back side. The crushable zone 113 includes a rib 114. The ribs 114 may be provided so as to have a lattice shape when viewed from the back side. The lattice shape may include various lattice shapes such as a square lattice, a rectangular lattice, or an orthorhombic lattice.

  As described in the description of FIG. 6, the crushable zone 113 can be deformed when an impact is applied in the negative direction of the Y axis with respect to the back side of the lower case 110. As the crashable zone 113 is deformed, an impact can be absorbed. As a result, the impact on the battery cell 150 accommodated in the lower case 110 can be reduced. The crashable zone 113 is also referred to as an impact absorbing structure. The crushable zone 113 is not limited to the back side of the lower case 110, and may be provided on the first side surface or the second side surface. The crushable zone 113 may be provided on the first side surface or the second side surface of the cell holder 120. The crashable zone 113 may be provided on the first side surface or second side surface of the BAT case 500, or on the front side.

  The assembled battery 100 may be mounted on the vehicle 800 (see FIG. 14), for example, with the bottom face down. The vehicle 800 may receive an impact from the front, rear, left and right. Further, the vehicle 800 may receive an inertial force in the front / rear and left / right directions. When the assembled battery 100 is mounted on the vehicle 800 with the bottom face down, the assembled battery 100 may receive an impact according to the impact received by the vehicle 800 or an inertial force. The assembled battery 100 can receive an impact from the front side, the back side, or each direction of the first side surface or the second side surface. Even when the assembled battery 100 receives an impact from each direction, the impact on the battery cell 150 can be reduced by the deformation of the crushable zone 113.

  The rigidity of the crashable zone 113 may be lower than the rigidity of the battery cell 150. Further, the rigidity of the rib 114 may be lower than the rigidity of the battery cell 150. By doing in this way, the crushable zone 113 including the rib 114 can be deformed before the battery cell 150 when the assembled battery 100 receives an impact due to the impact on the assembled battery 100. Further, when the rib 114 has a lattice shape, the impact on the assembled battery 100 is easily dispersed in the X-axis direction and the Z-axis direction, and can be efficiently absorbed by the entire rib 114. As a result, the impact on the battery cell 150 can be reduced. A pillar 117 is provided on the back side of the lower case 110. The rigidity of the pillar 117 may be higher than the rigidity of the rib 114. The pillar 117 having relatively high rigidity can reduce deformation of the lower case 110 when a force in the Z-axis direction is applied to the lower case 110.

  For example, as shown in FIG. 7, the assembled battery 100 includes members such as an inter-cell bus bar 160 and a sensor substrate 231 on the front side. The members such as the inter-cell bus bar 160 or the sensor substrate 231 can be deformed when an impact is applied to the assembled battery 100 from the front side in the positive direction of the Y axis. The impact can be absorbed by deformation of members such as the inter-cell bus bar 160 or the sensor substrate 231. Further, the rigidity of the bus bar or the substrate may be lower than the rigidity of the battery cell 150. By doing so, the bus bar or the substrate can be deformed before the battery cell 150 when the assembled battery 100 receives an impact due to the impact on the assembled battery 100. As a result, the impact on the battery cell 150 held by the cell holder 120 can be reduced. Members such as the inter-cell bus bar 160 or the sensor substrate 231 may be included in the shock absorbing structure. The sensor substrate 231 is also simply referred to as a substrate.

  As described above, the assembled battery 100 may include an impact absorbing structure on the side on which the impact is applied to the battery cell 150. By doing in this way, the battery cell 150 can become difficult to be damaged.

  FIG. 14 is a cross-sectional view illustrating a schematic configuration example of a vehicle 800 equipped with the assembled battery 100 according to the embodiment. It is assumed that the vehicle 800 shown in FIG. 14 travels with the direction facing the back side of the page as the front. The vehicle 800 includes a seat 801 on which an occupant such as a driver sits. The vehicle 800 includes a floor surface 803 and a center tunnel 802 that protrudes from the floor surface 803. The vehicle 800 includes the assembled battery 100 between the seat 801 and the floor surface 803. The position where the assembled battery 100 is provided in the vehicle 800 is not limited to the example of FIG. The assembled battery 100 may be provided at other positions such as a center console. The assembled battery 100 may be attached to the vehicle 800 by using a bolt or the like for the fixing portion 116.

  When an impact is applied to the vehicle 800, the assembled battery 100 can move in a direction along the floor surface 803 and collide with the center tunnel 802. When the assembled battery 100 collides with the center tunnel 802, it receives an impact from the center tunnel 802.

  In the example of FIG. 14, the assembled battery 100 is provided such that the crushable zone 113 faces the center tunnel 802. The assembled battery 100 may be provided such that an impact absorbing structure including members such as the inter-cell bus bar 160 or the sensor substrate 231 faces the center tunnel 802. By doing in this way, the impact which the assembled battery 100 receives from the center tunnel 802 can be absorbed. As a result, the impact on the battery cell 150 can be reduced. Even when the assembled battery 100 receives an impact from the center tunnel 802, the battery cell 150 is less likely to be damaged.

  FIG. 15 is a cross-sectional view showing a schematic configuration example of a vehicle 800 according to a comparative example. The example of FIG. 15 is different from the example of FIG. 14 in that the vehicle 800 includes a base 810.

  A vehicle 800 according to the comparative example includes a base 810. The assembled battery 100 is fixed to the base 810 by a fixing portion 116. When the assembled battery 100 is fixed to the base 810, movement in the direction along the floor surface 803 is restricted. The base 810 may be a flat plate-like member or a tray-like member having a flat bottom plate and a side plate protruding upward from the bottom plate. The base 810 has higher rigidity than the assembled battery 100. The rigidity of the base 810 is increased by including a metal material such as aluminum.

  The vehicle 800 according to the comparative example can make it difficult to receive an impact on the assembled battery 100 by fixing the assembled battery 100 to the base 810 regardless of whether the assembled battery 100 includes an impact absorbing structure. On the other hand, the base 810 increases the weight of the entire vehicle 800. When the base 810 includes a metal material, the assembled battery 100 easily receives heat from the vehicle 800. In this case, the assembled battery 100 is preferably provided at a position where the vehicle 800 generates relatively little heat. In other words, in the vehicle 800 according to the comparative example, the position where the assembled battery 100 is provided is restricted.

  In the vehicle 800 on which the assembled battery 100 including the shock absorbing structure is mounted, the overall weight can be reduced as compared with the vehicle 800 according to the comparative example. Further, the assembled battery 100 including the shock absorbing structure is attached to the vehicle 800 without using the base 810, so that the attachment position is not easily restricted.

  Although one embodiment according to the present disclosure has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various changes or modifications based on the present disclosure. Accordingly, it should be noted that these variations or modifications are included in the scope of the present disclosure. For example, the functions included in each means can be rearranged so as not to be logically contradictory, and a plurality of means can be combined into one or divided.

DESCRIPTION OF SYMBOLS 100 Battery assembly 110 Lower case 112 Convex part 113 Crushable zone 114 Rib 114a, 114b Intersection 115 Engagement hole 116 Fixing part 117 Pillar 118 Cell back plate 120 Cell holder 122 Protrusion part 125 Engagement hole 128 Engagement claw 130 First two Secondary battery 140 BMS (battery controller)
141 BMS board 142 Circuit component 143 Mounting hole 144 Fitting hole 145 Mounting member 146 Nut hole 147 Pin 150 Battery cell 151 Cap surface 152 Positive electrode terminal 153 Negative electrode terminal 154 Safety valve 155 Insulating sheet 160 Inter-cell bus bar 161 Protruding part 162a Terminal connecting part 162a Welding opening 163 Sensor mounting terminal 163a Nut 164 Total positive terminal bus bar 165 Total negative terminal bus bar 166 External connection 180 Engagement member 200 Auxiliary machine base 210 MOSFET
212 MOS substrate 220 Relay 230 Sensor 231 Sensor substrate 232 FPC
233 mounting member 240 fusible link 250 SSG terminal 260 LOAD terminal 270 GND terminal 280 GND copper bus bar 281 SSG copper bus bar 282 LOAD copper bus bar 285 total plus copper bus bar 286 total minus copper bus bar 300 upper case 301, 302, 303 recess 310 connector 312 MOS cable 314 Connector cable 340, 350 Volt 360 Relay fastening part 370 Fastening part (auxiliary machine base)
400 power supply system 410 alternator 420 starter 430 second secondary battery 440 load 450 switch 460 control unit 500 BAT case 502 convex portion 600 gas exhaust pipe 610, 611 safety valve cover 612, 613, 614 gas duct 620 gas tube 630 seal 800 vehicle 801 Seat 802 Center tunnel 803 Floor

Claims (5)

A battery cell;
A cell holder for holding the battery cell;
A lower case that houses the battery cell and engages the cell holder;
At least one of the cell holder and the lower case includes an impact absorbing structure on a side on which an impact is applied to the battery cell.
Assembled battery. The assembled battery according to claim 1,
An assembled battery that is mounted on a vehicle and includes the shock absorbing structure on a side facing the center tunnel of the vehicle. The assembled battery according to claim 1 or 2,
The battery pack includes a rib having a lower rigidity than the battery cell. The assembled battery according to any one of claims 1 to 3,
The shock absorbing structure is an assembled battery including lattice-shaped ribs. The assembled battery according to any one of claims 1 to 4,
An assembled battery comprising a bus bar or a substrate having lower rigidity than the battery cell as the shock absorbing structure on the cell holder side.