Battery pack

Abstract

To provide a battery pack with improved component placement efficiency.SOLUTION: A battery pack 10 includes: a plurality of cell modules 12; and one or more battery-related devices. The plurality of cell modules 12 are arranged side by side in a longitudinal direction via an intermediate space 16, and the one or more battery-related devices are arranged inside the intermediate space 16 or above the intermediate space 16.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present specification discloses a battery pack for use in a vehicle. [Background technology]

[0002] An electric vehicle is powered by a motor. An electric vehicle is equipped with a battery pack for charging and discharging power. A battery pack typically has multiple cell modules and one or more battery-related devices. A cell module is a component that integrates multiple battery cells. Battery-related devices include, for example, an ECU, connectors, and ducts.

[0003] Patent Document 1 discloses a battery pack in which multiple cell modules are arranged in the longitudinal direction of a vehicle. In Patent Document 1, the cell modules are generally rectangular parallelepipeds that are elongated in the vehicle width direction. Also in Patent Document 1, battery-related equipment is arranged adjacent to the cell modules in the vehicle width direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-234870 Summary of the Invention [Problem to be solved by the invention]

[0005] In order to reduce the width of the battery pack, multiple cell modules may be arranged in the length direction of the cell modules. In this case, depending on the arrangement of battery-related devices, the length direction of the battery pack may become excessively large.

[0006] Therefore, this specification discloses a battery pack with improved component layout efficiency. [Means for solving the problem]

[0007] The battery pack disclosed in this specification comprises a plurality of cell modules and one or more battery-related devices, the plurality of cell modules being arranged side by side in their respective longitudinal directions with an intermediate space interposed therebetween, and the one or more battery-related devices being arranged inside or above the intermediate space.

[0008] In this case, the one or more battery-related devices may include an electronic device arranged above the intermediate space and a connector arranged below the electronic device and electrically connecting the electronic device to a wire harness, and the longitudinal dimension of the intermediate space may be smaller than the longitudinal dimension of the electronic device.

[0009] The one or more battery-related devices may also include a fuse arranged inside the intermediate space, and a connector arranged inside or above the intermediate space to which wire harnesses drawn out from each of the plurality of cell modules are connected.

[0010] The connector may be arranged with an insertion port for the wire harness facing downward.

[0011] The one or more battery-related devices may also include a duct with a portion disposed inside the intermediate space. [Effects of the Invention]

[0012] According to the technology disclosed in this specification, component placement efficiency is improved. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a perspective view of the battery pack. [Figure 2] FIG. 2 is a schematic diagram showing the arrangement of a battery pack. [Figure 3]FIG. 2 is a schematic diagram showing a battery controller and the arrangement of the battery controller. [Figure 4] FIG. 2 is a schematic diagram showing the arrangement of fuses. [Figure 5] FIG. 2 is a schematic diagram showing the arrangement of ducts. [Figure 6] FIG. 10 is a diagram illustrating an example of another battery pack. DETAILED DESCRIPTION OF THE INVENTION

[0014] The configuration of the battery pack 10 will be described below with reference to the drawings. Fig. 1 is a schematic perspective view of the battery pack 10. In the following description, Fr, Up, and Rh respectively indicate the front, upper, and right side of the vehicle.

[0015] The battery pack 10 shown in FIG. 1 is mounted on an electric vehicle and supplies power to a traction motor. An electric vehicle is a vehicle that has a motor as one of its power sources, and examples of such vehicles include hybrid electric vehicles, battery electric vehicles, and fuel cell electric vehicles. The battery pack 10 is disposed in a location that will not be in the way of occupants, such as the luggage space or below a vehicle seat. In this example, the battery pack 10 is disposed below a rear seat 100, as shown in FIG. 2. In this example, the battery pack 10 is disposed in an orientation such that the longitudinal direction of a cell module 12, which will be described later, is parallel to the vehicle width direction. Therefore, the arrow Rh indicating the right side in FIGS. 1 to 6 is the same direction as the longitudinal direction of the cell module 12, and the arrow Fr indicating the forward direction is the same direction as the lateral direction of the cell module 12.

[0016] The battery pack 10 is configured by housing multiple cell modules 12 and one or more battery-related devices in a single case (not shown). The cell module 12 is configured by alternately stacking multiple battery cells 14 and multiple separators 15 in the thickness direction. The battery cells 14 are secondary batteries capable of charging and discharging. For example, the battery cells 14 are lithium-ion secondary batteries or sodium-ion secondary batteries. The battery cells 14 may also be all-solid-state batteries. The battery cells 14 are prismatic batteries with a flat, rectangular parallelepiped shape. The multiple battery cells 14 are electrically connected in series or in parallel by conductors called bus bars. The separators 15 are plates made of an insulating material. Grooves that function as flow paths for the flow of a cooling fluid are formed on the surface of the separators 15.

[0017] The cell module 12, which is made up of multiple stacked battery cells 14 and multiple separators 15, has a roughly rectangular parallelepiped shape that is long in the stacking direction. The battery pack 10 has two cell modules 12. In this example, the two cell modules 12 are arranged side by side in the longitudinal direction of the cell modules 12. This arrangement is intended to improve space efficiency, as will be described later. The battery pack 10 is arranged in an orientation in which the longitudinal direction of the cell modules 12 is roughly parallel to the vehicle width direction. Therefore, in this example, the longitudinal direction of the cell module 12 is roughly parallel to the vehicle width direction, and the short side direction of the cell module 12 is roughly parallel to the vehicle front-to-rear direction.

[0018] An intermediate space 16 is provided between two adjacent cell modules 12. The size of the intermediate space 16 is not particularly limited. However, if the intermediate space 16 is excessively large, the longitudinal dimension of the battery pack 10 will be large. On the other hand, if the intermediate space 16 is excessively small, it may be impossible to arrange the battery-related devices described below, or the work of connecting the wire harness 22 may be difficult. Therefore, the intermediate space 16 may be large enough, for example, to allow a worker's hand to enter. Therefore, the intermediate space 16 may be set, for example, in the range of 5 cm or more and less than 20 cm.

[0019] The battery pack 10 further includes one or more battery-related devices. The battery-related devices are devices necessary for safely operating the battery pack 10. For example, the battery controller 18, connector 20, fuse 24, duct 25, junction box 30, and service plug 32 correspond to the battery-related devices. The battery controller 18 is a computer that controls the charging and discharging of the cell modules 12, and is an electronic device generally called an ECU (Electronic Control Unit). The battery controller 18 has a flat rectangular shape and is disposed above the intermediate space 16.

[0020] A wire harness 22 drawn from the cell module 12 is electrically connected to the connector 20. For example, the connector 20 is a female connector into which a male connector attached to the end of the wire harness 22 is inserted. The connector 20 is also electrically connected to the battery controller 18. The connector 20 relays power or electrical signals between the battery controller 18 and the cell module 12. As shown in FIG. 1 , the connector 20 is disposed below the battery controller 18 with the insertion port for the wire harness 22 facing downward.

[0021] The fuse 24 is an electronic component that protects the cell module 12 from overcurrent. As shown in FIG. 1, the fuse 24 is disposed inside the intermediate space 16. The duct 25 is a flow path that connects the cooling flow path of the cell module 12 with a blower (not shown). As shown in FIG. 1, at least a portion of the duct 25 is disposed inside the intermediate space 16. Furthermore, the duct 25 and the fuse 24 are aligned in the short direction of the cell module 12 within the intermediate space 16.

[0022] The junction box 30 is an electronic component that unitizes relays that allow or block the flow of power. The junction box 30 is located above the cell module 12. The service plug 32 is a component that is installed at the midpoint of the power supply circuit and blocks high voltage when removed. When inspecting and servicing the battery pack 10, the worker removes the service plug 32 in advance. Then, after the inspection and servicing is completed, the worker reinserts the service plug 32. In this example, the service plug 32 is located above the cell module 12 and next to the junction box 30.

[0023] As is clear from the above explanation, in this example, the two cell modules 12 are arranged side by side in the longitudinal direction of the cell modules 12. The reason for this configuration will be explained. As described above, in this example, the battery pack 10 is arranged below the rear seat 100. The dimension of the underside of the rear seat 100 in the front-to-rear direction is smaller than the dimension in the vehicle width direction. Therefore, it is necessary to make the dimension of the battery pack 10 arranged below the rear seat 100 in the front-to-rear direction as small as possible.

[0024] Therefore, in this example, the two cell modules 12 are aligned in the longitudinal direction, and the battery pack 10 is placed below the rear seat 100 with this longitudinal direction approximately parallel to the vehicle width direction. By placing the battery pack 10 in this manner, the dimension of the battery pack 10 in the vehicle's fore-and-aft direction can be kept small.

[0025] In this example, an intermediate space 16 is provided between the two cell modules 12, and battery-related equipment is provided inside or above this intermediate space 16. The reason for this arrangement will be explained with reference to Figures 3 to 5. Figure 3 is a schematic diagram of the battery pack 10 as seen from the front. In Figure 3, state S1 in the upper row shows the arrangement of this example, while state S2 in the middle row and state S3 in the lower row each show arrangements of a comparative example.

[0026] First, consider the case where two cell modules 12 are arranged side by side with no gap between them, with the battery controller 18 and connector 20 located on the outside in the longitudinal direction, as in state S2. In this case, the longitudinal dimension of the battery pack 10 increases by the width of the battery controller 18. Furthermore, in state S2, the distance from the cell module 12 on the right side of the page to the connector 20 increases, resulting in a longer wire harness 22. Furthermore, in state S2, the battery controller 18 and connector 20 are located within the height range of the cell module 12. In this case, it is difficult to secure sufficient working space below the connector 20. As a result, there is a problem with poor workability when connecting the wire harness 22. Note that while workability can be improved by orienting the connector 20 with its socket facing upward, this also introduces another problem: foreign matter is more likely to adhere to the socket.

[0027] Therefore, as shown in state S3, it is also possible to arrange the two cell modules 12 with no gap between them and provide the battery controller 18 and connector 20 above the cell modules 12. Such an arrangement can reduce the longitudinal dimension of the battery pack 10. However, in this case, the battery controller 18 and connector 20 must be arranged far away from the cell modules 12 to ensure working space for connecting the wire harness 22 to the connector 20. As a result, in state S3, the height dimension of the battery pack 10 becomes significantly larger, making it difficult to arrange the battery pack 10 below the rear seat 100.

[0028] On the other hand, in this example, as shown in state S1, an intermediate space 16 is provided between the two cell modules 12. The battery controller 18 and the connector 20 are arranged above this intermediate space 16. In this case, the longitudinal dimension of the battery pack 10 can be made smaller than in state S2. The length of the wire harness 22 can also be significantly shortened. Furthermore, in this case, the intermediate space 16 can be used as a working space for connecting the wire harness 22. As a result, in state S1, the battery controller 18 and the wire harness 22 can be arranged close to the cell modules 12. This allows the height dimension of the battery pack 10 to be kept small.

[0029] In this example, in order to sufficiently reduce the longitudinal dimension of the entire battery pack 10, the longitudinal dimension of the intermediate space 16 is set smaller than both the longitudinal dimension of the battery controller 18 and the longitudinal dimension of the connector 20. However, if the installation space for the battery pack 10 is sufficiently large, the longitudinal dimension of the intermediate space 16 may be larger than the longitudinal dimension of the battery controller 18 or the longitudinal dimension of the connector 20. Both the battery controller 18 and the connector 20, or only the connector 20, may be disposed inside the intermediate space 16. With this configuration, the height dimension of the battery pack 10 can be reduced. Furthermore, as long as sufficient dustproofing measures are taken, the connector 20 may be disposed with its receptacle facing upward.

[0030] Next, the arrangement of the fuse 24 will be described with reference to Figure 4. Figure 4 is a schematic diagram of the battery pack 10 as viewed from the front. In Figure 4, state S4 in the upper row shows the arrangement of this example, and state S5 in the lower row shows the arrangement of a comparative example. When two cell modules 12 are arranged with no gap between them and the fuse 24 is arranged on the outer side in the longitudinal direction, as in state S5, the longitudinal dimension of the battery pack 10 increases, and the wire length of the wire harness 22 also increases. Furthermore, when the fuse 24 is arranged above the cell module 12, the height dimension of the battery pack 10 increases.

[0031] On the other hand, in this example, as shown in state S4, the fuse 24 is arranged inside the intermediate space 16. This shortens the wire length of the wire harness 22. In this example, the longitudinal dimension of the fuse 24 is smaller than both the longitudinal dimension of the connector 20 and the longitudinal dimension of the intermediate space 16. However, this arrangement and size of the fuse 24 are merely an example, and the fuse 24 may also be arranged outside the intermediate space 16. For example, the fuse 24 may be arranged above the intermediate space 16 or above the cell module 12.

[0032] Next, the arrangement of the duct 25 will be described with reference to Fig. 5. Fig. 5 is a schematic diagram of the battery pack 10 viewed from above. In Fig. 5, state S6 in the upper part shows the arrangement of this example, and state S7 in the lower part shows the arrangement of a comparative example. As shown in Fig. 5, the duct 25 is broadly divided into sub-ducts 27 connected to each cell module 12, and a main duct 26 where multiple sub-ducts 27 converge.

[0033] When two cell modules 12 are arranged with no gap between them, as in state S7, the main duct 26 needs to be arranged on the front or rear side of the cell module 12. For example, consider the case where the main duct 26 is arranged on the front side of the two cell modules 12. In this case, the sub-duct 27 connecting the main duct 26 to the cell module 12 runs from the outside of the longitudinal direction of the cell module 12, passing the front side of the cell module 12 and connecting to the main duct 26. As a result, the path of the sub-duct 27 becomes longer, and a large curve occurs along the path of the sub-duct 27. This increases pressure loss, reducing the cooling efficiency of the cell module 12. Furthermore, in state S7, a space is required to route the sub-duct 27, which increases the transverse dimension of the battery pack 10.

[0034] On the other hand, in this example, as in state S6, an intermediate space 16 is provided between two cell modules 12, and a portion of the main duct 26 is disposed inside this intermediate space 16. In this case, the subduct 27 extends in a straight line from the inner longitudinal end of the cell module 12 toward the main duct 26. As is clear from FIG. 5 , in state S6, the subduct 27 is significantly shorter and less curved than in state S7. As a result, in state S6, pressure loss can be reduced, improving the cooling efficiency of the cell modules 12. Furthermore, in state S6, the subduct 27 can be disposed within the lateral range of the cell module 12, thereby reducing the lateral dimension of the battery pack 10.

[0035] This arrangement of the duct 25 is also an example, and the duct 25 may be arranged outside the intermediate space 16. For example, the duct 25 may be arranged outside the two cell modules 12 in the longitudinal direction or outside the lateral direction.

[0036] In addition, in the above description, an example has been given in which the battery pack 10 has two cell modules 12. However, the number of cell modules 12 is not particularly limited as long as it is two or more, and may be, for example, three. In this case, as shown in the upper part of Fig. 6 (state S8), the battery pack 10 may have two intermediate spaces 16. A portion of the duct 25 may be disposed in each of the two intermediate spaces 16.

[0037] Furthermore, the battery pack 10 may have cell modules 12 adjacent in the width direction, provided that the battery pack 10 has multiple cell modules 12 adjacent in the length direction. That is, as shown in the lower part of Fig. 6 (state S9), four or more cell modules 12 may be arranged in an array in the length direction and width direction.

[0038] Furthermore, in the above description, the battery pack 10 is arranged in a position where the longitudinal direction of the cell modules 12 is approximately parallel to the width direction of the vehicle. However, the arrangement position of the battery pack 10 in the vehicle may be changed as appropriate. For example, the battery pack 10 may be arranged in a position where the longitudinal direction of the cell modules 12 is approximately parallel to the front-rear direction of the vehicle. [Explanation of symbols]

[0039] 10 Battery pack, 12 Cell module, 14 Battery cell, 15 Separator, 16 Intermediate space, 18 Battery controller, 20 Connector, 22 Wire harness, 24 Fuse, 25 Duct, 26 Main duct, 27 Sub-duct, 30 Junction box, 32 Service plug, 100 Rear seat.

Claims

1. a plurality of cell modules; one or more battery-related devices; Equipped with The plurality of cell modules are arranged side by side in the longitudinal direction of each cell module with an intermediate space therebetween, The one or more battery-related devices are disposed inside the intermediate space or above the intermediate space. A battery pack characterized by:

2. 2. The battery pack according to claim 1, The one or more battery-related devices include: an electronic device disposed above the intermediate space; a connector disposed below the electronic device and electrically connecting the electronic device and a wire harness; Including, The longitudinal dimension of the intermediate space is smaller than the longitudinal dimension of the electronic device. A battery pack characterized by:

3. 2. The battery pack according to claim 1, The one or more battery-related devices include: a fuse disposed within the intermediate space; a connector disposed inside the intermediate space or above the intermediate space, to which wire harnesses drawn out from each of the plurality of cell modules are connected; Including, A battery pack characterized by:

4. 4. The battery pack according to claim 2 or 3, The battery pack is characterized in that the connector is arranged with an insertion port for the wire harness facing downward.

5. 2. The battery pack according to claim 1, The battery pack, wherein the one or more battery-related devices include a duct, a portion of which is disposed inside the intermediate space.

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