BATTERY PACK

Abstract

A battery pack comprises a battery module, a lower housing to which the battery module is fixed, an upper frame located on the top of the vehicle relative to the lower housing, and a support element located on both sides of the battery module in the vehicle width direction. The support element is fixed to the lower and upper housings in a position where it extends in the upward / downward direction between the lower housing and the upper frame, supporting the upper frame from below. A first deformation start point section is provided on the side of a section of the support element that is fixed to the lower housing. This first deformation start point section serves as a deformation start point where deformation begins when the support element falls in one direction in the vehicle width direction.

Description

BACKGROUND OF THE INVENTION 1. Field of the invention

[0001] The present invention relates to a battery pack. 2. Description of the related prior art

[0002] The unexamined Japanese patent application disclosure no. 2013-134809 (JP 2013-134809 A) discloses a battery pack that can be installed in a vehicle, a house, etc. The battery pack contains multiple battery modules. A frame with an outer peripheral frame section that surrounds the outer perimeter of the battery modules is attached to the battery modules. The frame includes a section to be fixed to the battery modules, a mounting section that accommodates another frame, and a mounting section to be fixed to another element. The frame allows the battery modules to be stacked. The outer peripheral section of the frame has high rigidity to resist deformation of the battery modules. This makes it possible to create a structure in which the battery modules are stacked while suppressing deformation of the battery modules. BRIEF SUMMARY OF THE INVENTION

[0003] When the battery pack is installed in a vehicle, it may be desirable to reduce the displacement of the battery pack towards the top of the vehicle in the event of a side impact, depending on the position of the battery pack and the devices around the battery pack.

[0004] In light of the above, an objective of the present invention is to provide a battery pack that is less likely to be displaced towards the top of the vehicle in the event of a side impact.

[0005] One initial consideration envisions a battery pack comprising the following: a battery module configured to contain a plurality of battery cells; a lower floor element to which the battery module is attached; an upper floor element positioned on the upper surface of the vehicle relative to the lower floor element; a support element positioned on both sides in a vehicle width direction relative to the battery module and fixed to the lower floor element and the upper floor element in a state where it extends in an up / down direction between the lower floor element and the upper floor element, with the support element supporting the upper floor element from below;and a first deformation start point section provided on one side of a section of the support element that is fixed to the lower floor element, wherein the first deformation start point section serves as a deformation start point at which the deformation begins when the support element falls to one side in the vehicle width direction.

[0006] In the battery pack described in the first section, the battery module is fixed to the lower floor element. The upper floor element is located on the vehicle's upper surface, above the battery module fixed to the lower floor element. Furthermore, a support element extending between the lower and upper floor elements, in the vehicle's width direction, is provided on both sides of the battery module fixed to the lower floor element. If, in the event of a side impact, a load acts on the upper floor element in one direction, in the vehicle's width direction, the upper floor element is displaced in that direction, and the first deformation starting point section, located on the side of the section of the support element fixed to the lower floor element, is deformed, causing the support element to collapse in that direction.This prevents separation or breakage in the section of the support element that is fixed to the lower floor element, thereby preventing the upper floor element from shifting towards the top of the vehicle. In other words, it is possible to prevent the battery pack from shifting towards the top of the vehicle.

[0007] A second aspect provides the battery pack according to the first aspect, wherein: a load-bearing section is provided on an outer side in the vehicle width direction with respect to the upper floor element, the load-bearing section being contacted by the upper floor element, which is displaced to one side in the vehicle width direction; and a second deformation start point section is provided on an intermediate section in the vehicle up / down direction of the support element between the first deformation start point section and the upper floor element, the second deformation start point section serving as a deformation start point at which the deformation begins when the support element falls to another side in the vehicle width direction after it has contacted the load-bearing section.

[0008] If, according to the second aspect, a load is applied to the battery pack in a lateral direction (across the width of the vehicle) to displace the upper floor element in that direction, the upper floor element comes into contact with the load-bearing section, deforming the second deformation start point section of the support element. In this way, by deforming the support element with the second deformation start point section, which serves as a deformation start point in addition to the first, it is possible to further suppress displacement of the upper floor element towards the top of the vehicle. That is, it is possible to further suppress displacement of the battery pack towards the top of the vehicle.

[0009] A third viewpoint provides for the battery pack according to the second viewpoint, in which: the battery modules are coupled in the vehicle's up / down direction in a state in which they are stacked in the vehicle's up / down direction; and a position of the second deformation start point section in the vehicle's up / down direction is set to the same position as a position of a coupling section between one of the battery modules and another of the battery modules in the vehicle's up / down direction.

[0010] In the battery pack according to the third aspect, the position of the second deformation start point section of the support element in the vehicle's up / down direction is set to the same position as the position of the coupling section between one of the battery modules and another in the vehicle's up / down direction. With this configuration, it is possible, if the second deformation start point section is deformed, to suppress the second deformation start point section that is deformed to the side of the battery module and contacts both the first and second battery modules.

[0011] A fourth consideration provides for the battery pack according to the second or third consideration, wherein a third deformation start point section is provided on one side of a section of the support element that is fixed to the upper bottom element, the third deformation start point section serving as a deformation start point at which the deformation begins after the upper bottom element touches the load-bearing section.

[0012] In the battery pack, according to the fourth aspect, when a load is applied to one side in the vehicle width direction to displace the upper floor element to that side in the vehicle width direction, the upper floor element comes into contact with the load-bearing section to deform the third deformation start point section of the support element. In this way, by deforming the support element with the third deformation start point section, which serves as the deformation start point in addition to the first and second deformation start point sections, it is possible to further suppress displacement of the upper floor element towards the top of the vehicle. That is, it is possible to further suppress displacement of the battery pack towards the top of the vehicle.

[0013] A fifth aspect provides the battery pack according to one of the first to fourth aspects, wherein: the battery cells are solid-state batteries and are arranged in a state in which they are positioned in a vehicle forward / reverse direction; an end plate is fixed to a section on a vehicle front and a section on a vehicle top of the battery module; and the end plate is fixed to each of the lower bottom element and the upper bottom element.

[0014] In the battery pack described in the fifth aspect, the end plate is fixed to both the front and rear sections of the battery module. Furthermore, the end plate is fixed to both the lower and upper bottom elements. This configuration, where the upper bottom element is fixed to the battery module's end plate and the lower bottom element, further suppresses upward displacement of the upper bottom element. Solid-state batteries, in particular, have a very rigid structure to withstand high restraining pressure, thus further suppressing upward displacement of the upper bottom element towards the top of the vehicle. In other words, it further suppresses upward displacement of the battery pack.

[0015] The battery pack according to the present invention has the excellent effect that, in the event of a side impact of a vehicle, it is less likely to be displaced towards the top of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Features, advantages and technical and industrial significance of embodiments of the invention are described below with reference to the accompanying drawings, in which the same symbols denote the same elements and in which: Fig. Figure 1 is a perspective view showing a battery pack with the top cover removed; Fig. Figure 2 is a cross-sectional view of the battery pack in the vehicle width direction and upward / downward direction; Fig. Figure 3 is a cross-sectional view accordingly Fig. 2, which schematically shows a state in which a load is applied due to a side impact; and Fig. Figure 4 is a cross-sectional view, which Fig. 3 corresponds to and illustrates a state in which first deformation start point sections, second deformation start point sections and third deformation start point sections are deformed. DETAILED DESCRIPTION OF THE EXECUTION EXAMPLES

[0017] A battery pack 10 according to an embodiment of the present invention is described below with reference to the drawings. Of the arrows indicated in the drawings, arrow FR denotes the front of the vehicle, arrow UP the top of the vehicle, arrow LH the left side in the direction of the vehicle's width (right / left direction), and arrow RH the right side in the direction of the vehicle's width (right / left direction). When the directions forward / backward, up / downward, and right / left are indicated in the following description, these directions refer to forward / backward in the direction of the vehicle's forward / backward movement, up / downward in the direction of the vehicle's upward movement, and right / left in the direction of the vehicle's right / left movement, unless otherwise specified.

[0018] As in Fig. 1 and Fig. As shown in Figure 2, a battery pack 10 comprises: a battery module 12 configured to contain a plurality of battery cells; a lower housing 14 serving as the lower base element to which the battery module 12 is fixed; and an upper frame 16 serving as the upper base element and positioned above the lower housing 14. The battery pack 10 also comprises: a pair of right and left support elements 18 supporting the upper frame 16 from below; a device 20 fixed to the upper frame 16; and an upper cover 22 covering the battery module 12, the device 20, etc., from above.

[0019] The battery module 12 is configured such that a plurality of battery cells are arranged as solid-state batteries in a forward / reverse direction and has an overall shape of a rectangular parallelepiped. An end plate 24 is fixed to each of the front and rear sections of the battery module 12. The end plate 24 is fixed to the lower housing 14 and the upper frame 16, respectively, as described later. Fig. The end plate 24 is not shown in Figure 2. In the present embodiment, two battery modules 12 are stacked and coupled in an upward / downward orientation. In the following description, the lower battery module 12 is occasionally referred to as the first-layer battery module 12, and the upper battery module 12 is occasionally referred to as the second-layer battery module 12.

[0020] The lower housing 14 has the shape of a rectangular plate extending in the forward / backward and right / left directions, and exhibiting an upward / downward thickness. A plurality of screw sections 14A for battery mounting bolts are provided in the central right / left direction of the lower housing 14. The battery mounting bolts 26 are screwed into the screw sections 14A. In the present embodiment, four battery mounting bolt screw sections 14A are provided on the central right / left direction of the front section of the lower housing 14, and four battery mounting bolt screw sections 14A are provided on the central right / left direction of the rear section of the lower housing 14.

[0021] Four battery mounting bolts 26 are inserted into the end plate 24, which is fixed to the front section of the first-level battery module 12. These four battery mounting bolts 26 are each screwed into the four screw sections 14A provided in the middle section, oriented clockwise / counterclockwise, of the front section of the lower housing 14. Similarly, four battery mounting bolts 26 are inserted into the end plate 24, which is fixed to the rear section of the first-level battery module 12. These four battery mounting bolts 26 are each screwed into the four screw sections 14A provided in the middle section, oriented clockwise / counterclockwise, of the rear section of the lower housing 14. This allows the first-level battery module 12 to be fixed to the lower housing 14.

[0022] Furthermore, four battery mounting bolts 26 are inserted into the end plate 24, which is fixed to the front section of the second-layer battery module 12. These four battery mounting bolts 26 are each screwed into the upper sections of the four battery mounting bolts 26 on the side of the first-layer battery module 12. Similarly, four battery mounting bolts 26 are inserted into the end plate 24, which is fixed to the rear section of the second-layer battery module 12. These four battery mounting bolts 26 are each screwed into the upper sections of the four battery mounting bolts 26 on the side of the first-layer battery module 12. This allows the second-layer battery module 12 to be fixed to the lower housing 14.

[0023] Furthermore, two first screw sections 14B are provided on the left section of the lower housing 14. First fastening bolts 34 are screwed into these first screw sections 14B as described later. These two first screw sections 14B are spaced apart in the forward / backward direction. Two further first screw sections 14B are provided on the right section of the lower housing 14. First fastening bolts 34 are screwed into these first screw sections 14B as described later. These two first screw sections 14B are spaced apart in the forward / backward direction.

[0024] The upper frame 16 has the form of a rectangular plate extending forward / backward and right / left, with an upward / downward thickness. Four frame mounting bolts 28 are inserted into the front section of the upper frame 16. These four frame mounting bolts 28 are each screwed into the upper sections of the four battery mounting bolts 26 on the side of the second-level battery module 12. Similarly, four frame mounting bolts 28 are inserted into the rear end section of the upper frame 16. These four frame mounting bolts 28 are each screwed into the upper sections of the four battery mounting bolts 26 on the side of the second-level battery module 12. In this way, the upper frame 16 can be fixed to the upper part of the second-level battery module 12. Furthermore, the device 20 is provided on the top of the upper frame 16.The device 20 is fixed to the upper part of the upper frame 16. The device 20 can be a device for charging and discharging the battery module 12 or a device with another function.

[0025] The right and left support elements 18 are arranged on both sides in the vehicle width direction with respect to the battery module 12 and are fixed to the lower housing 14 and the upper frame 16, extending in an upward / downward direction between the lower housing 14 and the upper frame 16. Each support element 18 is configured to include a first bracket 30, a second bracket 32, first fastening bolts 34, second fastening bolts 36, and third fastening bolts 38.

[0026] The first support 30 has the form of a rectangular plate extending in the forward / backward and upward / downward directions and exhibiting a thickness in the right / left direction. A first fastening bolt insertion hole 30A is formed on both the front and rear sections of the first support 30, into which the first fastening bolt 34 is inserted.

[0027] Like the first bracket 30, the second bracket 32 ​​also has the shape of a rectangular plate extending in the forward / backward and upward / downward directions and exhibiting a thickness in the right / left direction. A second mounting bolt insertion hole 32A, into which the second mounting bolt 36 is inserted, is formed on both the front and rear sections of the second bracket 32.

[0028] In the left support element 18, the first two fastening bolts 34, which are inserted into the front and rear insertion holes 30A of the first support 30 for the fastening bolts, are screwed into the two screw sections 14B for the first fastening bolts provided in the left section of the lower housing 14. Furthermore, the two second fastening bolts 36, which are inserted into the front and rear second fastening bolt insertion holes 32A of the second support 32, are screwed into the upper end sections of the two first fastening bolts 34. Finally, the two third fastening bolts 38, which are inserted into the left section of the upper frame 16, are screwed into the upper end sections of the two second fastening bolts 36.

[0029] In the right-hand support element 18, the first two fastening bolts 34, which are inserted into the front and rear insertion holes 30A of the first support 30 for the fastening bolts, are screwed into the two screw sections 14B for the first fastening bolts provided in the right-hand section of the lower housing 14. Furthermore, the two second fastening bolts 36, which are inserted into the front and rear second fastening bolt insertion holes 32A of the second support 32, are screwed into the upper end sections of the two first fastening bolts 34. Additionally, the two third fastening bolts 38, which are inserted into the right-hand section of the upper frame 16, are screwed into the upper end sections of the two second fastening bolts 36.

[0030] Here, the section of the first fixing bolt 34, which is screwed into the screw section 14B of the first fixing bolt, serves as the first deformation start point section 18A, which acts as the deformation start point where deformation begins when a load is applied due to a side impact. Furthermore, the section of the second screw bolt 36, which is screwed into the first screw bolt 34, serves as a second deformation start point section 18B, which acts as a deformation start point where deformation begins when a load is applied due to a side impact and the support element falls to the other side in the vehicle width direction.The position of the second deformation start point section 18B in the upward / downward direction is the same as the position of the screw sections 26A of the upper and lower battery mounting bolts 26 as the coupling sections between the battery module 12 of the first layer and the battery module 12 of the second layer. Furthermore, the section of the third mounting bolt 38, which is screwed into the second mounting bolt 36, serves as the third deformation start point section 18C, which acts as the deformation start point at which deformation begins when a load is applied due to a side impact.

[0031] As in Fig. As shown in Figure 2, the upper cover 22 is shaped to have a hat-shaped cross-section with an open underside when viewed in cross-section along the upward / downward and right / left directions. The lower end sections of the upper cover 22 on both sides in the right / left direction are fixed to both end sections in the right / left direction of the lower housing 14. In this way, the battery modules 12, the upper frame 16, the device 20, and the right and left support elements 18 can be covered by the upper cover 22 from above and in the right / left direction. The sections of the upper cover 22 facing the right and left end sections of the upper frame 16 in the right / left direction each form a load-bearing section 22A. Functions and effects of the present embodiment

[0032] The following describes the functions and effects of the present embodiment.

[0033] When a load F1 acts on the upper frame 16 in the direction of the left side, as in Fig. As shown in Figure 3, for example, in the case of a lateral displacement of a vehicle equipped with the battery pack 10 according to the embodiment described above, the upper frame 16 is displaced to one side in the direction of the vehicle's width, while the right and left support elements 18 are tilted to the left. Then, the first deformation start point sections 18A of the right and left support elements 18 are plastically deformed, causing the support elements 18 to fall to the left. This prevents separation or breakage of the section of the support elements 18 that is fixed to the lower housing 14, thus preventing the upper frame 16 from displacing upwards. That is, it is possible to prevent the battery pack 10 from displacing upwards.Furthermore, by suppressing the upward displacement of the upper frame 16, it is possible to prevent contact between the device 20 fixed to the upper part of the upper frame 16 and the upper cover 22.

[0034] When the upper frame 16 is displaced to the left, the left end section of the upper frame 16 comes into contact with the load-bearing section 22A of the upper cover 22, and a reaction load F2 is transferred from the load-bearing section 22A to the upper frame 16. As a result, the second deformation start point sections 18B of the right and left support elements 18 are plastically deformed, as shown in Fig. Figure 4 illustrates this. In this way, further upward displacement of the upper frame 16 can be prevented by deforming the support elements 18 with the second deformation start point sections 18B, which serve as deformation start points in addition to the first deformation start point sections 18A. That is, it is possible to further suppress upward displacement of the battery pack 10. In this case, when the second deformation start point sections 18B are deformed, the second supports 32 are displaced so that they tilt to the right relative to the first supports 30.

[0035] Here, the position of the second deformation start point section 18B of the support element 18 in the upward / downward direction in the state before the side impact (which is shown in Fig. (2 state shown) is set to the same position as the position of the coupling section between the first layer battery module 12 and the second layer battery module 12 in the upward / downward direction. This configuration prevents the second deformation start point section 18B from coming into contact with the side faces of the first layer battery module 12 and the second layer battery module 12 when the second deformation start point section 18B is deformed.

[0036] Furthermore, the third deformation start point sections 18C of the support elements 18 are deformed when the left end section of the upper frame 16 comes into contact with the load-bearing section 22A of the upper cover 22 and a reaction load F2 from the load-bearing section 22A acts on the upper frame 16. In this way, by deforming the support elements 18 with the third deformation start point sections 18C, which serve as deformation start points in addition to the first deformation start point sections 18A and the second deformation start point sections 18B, it is possible to further suppress upward displacement of the upper frame 16. That is, it is possible to further suppress upward displacement of the battery pack 10.

[0037] As in Fig.As shown in Figure 1, in the battery pack 10 according to the present embodiment, the end plate 24 is fixed to each of the front and rear sections of the battery module 12. Furthermore, the end plate 24 is fixed to each of the lower housings 14 and the upper frame 16. With this configuration, in which the upper frame 16 is fixed to the end plate 24 of the battery module 12 and the lower housing 14, it is possible to further suppress upward displacement of the upper frame 16. In particular, solid-state batteries have a very rigid structure to withstand the application of high restraining pressure, and therefore it is possible to further suppress upward displacement of the upper frame 16.

[0038] While the first deformation start point section 18A is the section of the first fastening bolt 34, which in the present embodiment is screwed into the screw section 14B of the first fastening bolt, the present invention is not limited to this. It is only necessary that the first deformation start point section 18A be formed as the start point of the deformation. For example, a structure with lower stiffness can be used, a groove or hole can be provided, or a different material can be used. This can also apply to the second deformation start point section 16B and the third deformation start point section 18C.

[0039] While the battery module 12 in the present embodiment contains a plurality of battery cells as solid-state batteries, the present invention is not limited thereto. For example, the battery module 12 can be configured to contain a plurality of battery cells containing an electrolyte.

[0040] While in the present embodiment the battery module 12 is fixed to the lower housing 14 and the upper frame 16 via the end plate 24, the present invention is not limited thereto. For example, the battery module 12 can be fixed to the lower housing 14 and the upper frame 16 by a fastening structure having a different configuration than that of the end plate 24.

[0041] While the support element 18 is deformed not only using the first deformation start point section 18A, but also the second deformation start point section 18B and the third deformation start point section 18C as deformation start points, the present invention is not limited thereto. It can be optionally specified whether the second deformation start point section 18B and the third deformation start point section 18C should be provided, taking into account the configuration around the battery pack 10, etc.

[0042] While one embodiment of the present invention has been described above, the present invention is not limited to it, and it is of course possible to implement the present invention in various other modified forms without deviating from the basic idea and scope of the present invention. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2013-134809

[0002] JP 2013-134809 A

[0002]

Claims

[1] Battery pack comprising the following: a battery module configured to include a large number of battery cells; a lower base element to which the battery module is attached; an upper floor element that is arranged on the upper surface of a vehicle in relation to the lower floor element; a support element arranged on both sides of the battery module in a vehicle width direction and fixed to the lower floor element and the upper floor element in a state in which it extends in a vehicle up / down direction between the lower floor element and the upper floor element, the support element supporting the upper floor element from a lower side; and a first deformation start point section provided on one side of a section of the support element fixed to the lower floor element, wherein the first deformation start point section serves as a deformation start point at which deformation starts when the support element falls in one direction in the vehicle width direction. [2] Battery pack according to claim 1, wherein: a load-bearing section is provided in relation to the upper floor element on an outer side in the vehicle width direction, wherein the load-bearing section is contacted by the upper floor element, which is displaced in the direction of one side in the vehicle width direction; and A second deformation start point section is provided at an intermediate section in the vehicle's upward / downward direction of the support element between the first deformation start point section and the upper floor element, wherein the second deformation start point section serves as a deformation start point at which deformation begins when the support element falls in a different direction in the vehicle's width direction after touching the load-bearing section. [3] Battery pack according to claim 2, wherein: a large number of battery modules in a state where they are stacked in the vehicle's up / down direction, coupled in the vehicle's up / down direction; and a position in the vehicle's upward / downward direction of the second deformation start point section is set to the same position as a position in the vehicle's upward / downward direction of a coupling section between one of the battery modules and another of the battery modules. [4] Battery pack according to claim 2 or 3, wherein a third deformation start point section is provided on one side of a section of the support element which is fixed to the upper bottom element, wherein the third deformation start point section serves as a deformation start point at which deformation starts after the upper bottom element touches the load-bearing section. [5] Battery pack according to claim 1, wherein: the battery cells are solid-state batteries and are arranged in a state where they are positioned in a vehicle forward / reverse direction; an end plate is fixed to each of an end section on a vehicle front and an end section on a vehicle rear of the battery module; and the end plate is fixed to each of the lower floor element and the upper floor element.

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