Battery pack

Abstract

The utility model relates to a battery pack which is provided with a battery module and a bracket arranged on the battery module. The housing portion of the battery module has a first side portion and a second side portion that intersect at an intersection portion. The bracket is disposed so as to face the first side portion, and is connected to the intersection portion. The bracket is separated from the first side portion outside the intersection portion. Thus, in a vehicle in which the battery pack is mounted, the battery can be protected from impact even if the collision stroke is small.

Description

Technical Field

[0001] The present utility model relates to a battery pack mounted on a vehicle. Background Art

[0002] Patent Document 1 discloses a battery mounting structure for a vehicle. The battery mounting structure for a vehicle is configured such that a battery and a vehicle body are joined by a bracket, so that the battery does not interfere with the vehicle body when an impact occurs.

[0003] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-82818 Summary of the Utility Model

[0004] The inventors of the present application have first recognized the following technical problems in a battery pack mounted on a vehicle: If the battery mounting amount is increased, then as a price thereof, the remaining length during impact application, i.e., the collision stroke, becomes smaller, and as a result, the battery is liable to be damaged. In an electric vehicle, the cruising range can be extended by increasing the battery mounting amount. On the other hand, the fact that the space occupied by the battery becomes larger means that the collision stroke becomes smaller. A smaller collision stroke necessarily increases the risk of battery damage when an impact is applied.

[0005] An object of the present utility model is to provide a technique capable of protecting a battery from the influence of an impact even when the battery mounting amount is increased, i.e., when the collision stroke is small.

[0006] The first aspect of the present utility model relates to a battery pack mounted on a vehicle. The battery pack includes a battery module and a bracket mounted on the battery module. The outer shell portion of the battery module has a first side portion and a second side portion that cross at a crossing portion. The bracket is arranged to face the first side portion and is connected to the crossing portion, and the bracket is separated from the first side portion outside the crossing portion.

[0007] The second aspect of the present utility model is that, on the basis of the first aspect, the bracket has a leg portion and a fragile portion. The leg portion is adjacent to the crossing portion of the first side portion and the second side portion. The fragile portion is located at a position farther from the first side portion than the leg portion and has a lower rigidity than the leg portion.

[0008] The third aspect of the present utility model is that, on the basis of the second aspect, the fragile portion provided on the bracket is located at the position farthest from the first side portion in the bracket.

[0009] The fourth aspect of the present utility model is that, on the basis of any one of the first to third aspects, the surface of the bracket facing the first side portion is arched.

[0010] The fifth aspect of the present utility model is that, on the basis of any one of the first to third aspects, the first side portion is arranged to face the side surface of the vehicle.

[0011] According to the first method, the bracket installed on the outer shell of the battery module is connected to the first side of the outer shell at the intersection and separated outside the intersection. Therefore, the load input to the first side of the battery module is transmitted to the second side of the outer shell through the bracket and the intersection. Since the load transfer to the central part of the first side is suppressed, the battery main body in the battery module is protected from the impact. Since it is easy to protect the battery main body from the impact, the collision stroke can be reduced. This helps to increase the battery loading capacity.

[0012] According to the second method, a fragile part is provided locally on the bracket. The rigidity of the fragile part is set smaller than that of the leg of the bracket. The load input to the first side first deforms or breaks the fragile part. The impact energy is absorbed by the deformation or breakage of the fragile part. This also helps to protect the battery main body in the battery module.

[0013] According to the third method, the fragile part existing in the bracket is provided at the position farthest from the first side. Since this position is the position closest to the outside, it is the position that is likely to bear the load during impact. Therefore, setting the fragile part at the position farthest from the first side to absorb the impact energy helps to protect the battery during impact.

[0014] According to the fourth method, the surface of the bracket opposite to the first side is arched. By making it arched, the load can be efficiently transmitted from the top of the arch to the intersection.

[0015] According to the fifth method, the first side is arranged to face the side of the vehicle. The present utility model is particularly effective when there is an impact from the side of the vehicle where the collision stroke is likely to become smaller compared to the front-rear direction of the vehicle. Description of the Drawings

[0016] Figure 1 It is a schematic diagram showing an example of a vehicle equipped with a battery pack.

[0017] Figure 2A 、 Figure 2B It is a perspective view for explaining the comparative example.

[0018] Figure 3 It is a schematic diagram for explaining the technical problem.

[0019] Figure 4A 、 Figure 4B It is a schematic diagram showing a configuration example of the battery pack according to the embodiment of the present utility model and its effects.

[0020] Figure 5A 、 Figure 5B It is a perspective view showing a configuration example of the bracket according to the embodiment of the present utility model.

[0021] Figure 6A 、Figure 6B The figure is a schematic view showing another configuration example of the battery pack related to the embodiment of the present utility model. Detailed Embodiment

[0022] Embodiments of the present utility model will be described with reference to the accompanying drawings.

[0023] Figure 1 The figure is a schematic view of a vehicle 100 equipped with a battery pack 1. Figure 1 The x-axis direction shown corresponds to the front of the vehicle 100 equipped with the battery pack 1. Similarly, the y-axis direction corresponds to the left side when viewed from the front of the vehicle 100, and the z-axis direction corresponds to the direction toward the upper side of the vehicle 100. The battery pack 1 is used, for example, as a power source for electric vehicles such as BEV, PEV, and HEV.

[0024] The battery pack 1 includes one or more battery modules 30 and a battery housing 2. The one or more battery modules 30 are housed in the battery housing 2.

[0025] Figure 2A 、 Figure 2B The figure is a schematic view showing the configuration of the battery module 30 related to the comparative example.

[0026] As Figure 2A shown, the battery module 30 can house a battery stack 300 and has a housing portion 31 for resisting loads input from the outside of the vehicle. That is, the battery stack 300 is housed in the housing portion 31. The battery stack 300 is formed by integrating a plurality of battery cells. The battery cell is a secondary battery capable of charging and discharging, such as a lithium-ion secondary battery.

[0027] The housing portion 31 has a first side portion 10 and a second side portion 20. The first side portion 10 and the second side portion 20 intersect at an intersection portion 12. The first side portion 10 and the second side portion 20 may also be orthogonal at the intersection portion 12. In Figure 2A 、 Figure 2B the example shown, the first side portion 10 faces the side of the vehicle. The first side portion 10 is sometimes also referred to as an end plate. In addition, the housing portion 31 may be generally rectangular parallelepiped in shape and, in addition to the first side portion 10 and the second side portion 20, also has a bottom surface (a plane along the Figure 2A xy plane in

[0028] As Figure 2B shown, the battery module 30 is connected to the battery housing 2 via a bracket 32A mounted on the housing portion 31 using a joining member 2A.

[0029] The inventors of the present application have first recognized the following technical problem regarding the battery pack 1 as described above: If the battery loading amount is increased, as a price, the extra length during impact, that is, the collision stroke, becomes smaller. As a result, the battery main body in the battery module is easily damaged.

[0030] In an electric vehicle, increasing the battery capacity can extend the cruising range. On the other hand, the increased space occupied by the battery means a smaller collision stroke. A smaller collision stroke will inevitably increase the risk of damage to the battery body when an impact is applied. Therefore, a structure is needed that can protect the battery body from the impact even when the battery capacity is increased, i.e., when the collision stroke is small. In particular, such a structure is needed for impacts from the side direction of the vehicle where the distance between the battery body and the outside of the vehicle is short.

[0031] The following describes the case of load transfer during a side collision in the comparative example. As Figure 3 shown, in the comparative example, the bracket 32A is connected to the entire range of the first side portion 10. Therefore, when a load 200 is applied to the first side portion 10 from the outside, the load 200 is transmitted to the entire first side portion 10 through the bracket 32A along the load transfer path shown by the dashed arrow in the figure. Since the battery stack 300 is housed on the side of the first side portion 10 opposite to the bracket 32A, in this case, the load 200 is likely to be transmitted to the battery stack 300, and as a result, the battery stack 300 is likely to be damaged.

[0032] In the above description, the risk of battery damage during an impact caused by increasing the battery capacity was mentioned. Therefore, in the present embodiment, a structure is proposed in which the bracket 32 is separated from the first side portion 10 so that the load 200 is not transmitted to the first side portion 10 but is transmitted to the second side portion 20, thereby suppressing damage to the battery stack 300.

[0033] Figure 4A 、 Figure 4B is a schematic diagram showing a configuration example of the battery pack 1 according to the embodiment of the present invention and its effects.

[0034] Figure 4A is a perspective view showing the present embodiment. The bracket 32 is connected to the intersection portion 12 of the first side portion 10 and the second side portion 20, and the first side portion 10 and the bracket 32 are separated outside the intersection portion 12. Thus, as Figure 4B shown, the load 200 applied to the first side portion 10 is transmitted from the bracket 32 to the second side portion 20 through the intersection portion 12 along the load transfer path shown by the dashed arrow in the figure. Thus, the effect of protecting the battery stack 300 during an impact can be expected. Moreover, since it is easy to protect the battery stack 300 from the impact, the collision stroke can be reduced. This helps to increase the battery capacity.

[0035] Figure 5A 、 Figure 5B is a perspective view showing a configuration example of the bracket 32 according to the embodiment of the present invention.

[0036] As Figure 5AAs shown, a vulnerable part 32a can also be provided locally on the bracket 32. The rigidity of the vulnerable part 32a is set to be smaller than that of the part (leg part 32b) adjacent to the bracket 32 and the first side part 10. The load input toward the first side part first deforms or breaks the vulnerable part 32a. By deforming or breaking the vulnerable part 32a, impact energy is absorbed, which helps protect the battery stack 300. In addition, as a method of implementing the vulnerable part 32a, the cross-sectional area can be locally reduced, or the material can be locally changed.

[0037] And, as Figure 5A shown, the vulnerable part 32a can also be provided at the position Y1 farthest from the first side part. The position Y1 is the position closest to the outside of the vehicle, so it is the position most likely to bear the load during impact. Therefore, setting the vulnerable part at the position Y1 to absorb impact energy helps protect the battery stack 300.

[0038] In addition, as the shape of the bracket 32, as Figure 5B shown, the surface 32c opposite to the first side part 10 can also be arched. By forming it into an arch shape, the load can be efficiently transmitted to the second side part 20 via the leg part 32b. In addition, in the way of making an arched cut in a rectangular plate as shown in this figure, a wide shoulder part 32d is formed on the bracket 32. Since the width of the shoulder part 32d is wide, holes 32e for joining the bracket 32 and the battery case 2 can be provided. This means that the joining of the bracket 32 and the battery case 2 can be simply carried out. And, since the cross-sectional area is the smallest at the top of the arch, the above-mentioned vulnerable part 32a is formed, and impact energy absorption can be expected, which helps protect the battery.

[0039] Figure 6A , Figure 6B It is a schematic diagram showing another structural example of the battery pack 1 according to the embodiment of the present utility model.

[0040] In Figure 6A a more specific embodiment is shown. The first side part 10 has a convex part 13 adjacent to the crossing part 12. As in the example shown in Figure 5B , the surface 32c opposite to the first side part 10 of the bracket 32 is arched, and the leg part 32b has a thickness in the z-axis direction. The upper surface of the leg part 32b and the upper surface of the convex part 13 are combined without a height difference to form a plane 33 along the xy plane. A joining plate 40 is provided on the plane 33 so as to straddle the boundary between the convex part 13 and the leg part 32b. The convex part 13 and the leg part 32b are connected by bolts 41 passing through the joining plate 40.

[0041] In addition, in the embodiments showing the present utility model Figure 4A , Figure 4B and Figure 6AIn [the figure], the bracket 32 contacts the first side portion 10, but as the form of the crossing portion 12, it may also be the form in which the bracket 32 contacts the second side portion 20 as shown in Figure 6B . That is, either the first side portion 10 or the second side portion 20 constituting the crossing portion 12 may contact the bracket 32. Even when the second side portion 20 contacts the bracket 32, the effects of the present utility model can be achieved.

[0042] The battery pack 1 proposed by the present utility model is particularly effective against an impact from the side of the vehicle 100 where the collision stroke is likely to be smaller than that in the front-rear direction of the vehicle 100. However, the arrangement direction of the battery pack 1 or the direction of the applied impact is not limited to this embodiment.

Claims

1. A battery pack mounted on a vehicle, characterized in that: A battery module and a bracket mounted on the battery module, The outer shell of the battery module has a first side portion and a second side portion intersecting at an intersection portion, The bracket is disposed so as to face the first side portion and is connected to the intersection portion, and the bracket is separated from the first side portion except for the intersection portion.

2. The battery pack according to claim 1, characterized in that: The bracket has a leg portion and a fragile portion, The leg portion is adjacent to the intersection portion, The fragile portion is located farther from the first side portion than the leg portion and has lower rigidity than the leg portion.

3. The battery pack according to claim 2, characterized in that: The fragile portion exists at a position of the bracket farthest from the first side portion.

4. The battery pack according to any one of claims 1 to 3, characterized in that: A surface of the bracket facing the first side portion is arched.

5. The battery pack according to any one of claims 1 to 3, characterized in that: The first side portion is provided to face a side surface of the vehicle.

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