Coupling structure of battery case

Abstract

To prevent a blade edge of a cutter from entering a battery case when a high-voltage part is arranged close to a flange.SOLUTION: The lower flange 50 is disposed at the peripheral edge of the tray portion 42. The upper flange 30 is disposed on the peripheral edge of the cover portion 22. The lower flange 50 and the upper flange 30 are sealed with an adhesive 70. In the tray portion 42, a terminal 82, which is a high-voltage portion, is disposed in the vicinity of the lower flange 50 and the upper flange 30. A rib 60 for separating the adhesive 70 from the terminal 82 is formed on the upper flange 30 or the lower flange 50.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] This specification discloses a connection structure for a battery case mounted on a vehicle. [Background technology]

[0002] An electric vehicle (BEV) is equipped with a battery pack. The battery pack includes a plurality of batteries and a battery case. The plurality of batteries are housed in the battery case.

[0003] For example, in Patent Document 1, the battery case is composed of a cover and a tray. The cover is also called the upper case, and the tray is also called the lower case.

[0004] Flanges are provided on the periphery of each of the upper and lower cases. In Patent Document 2, the gap between the flanges of the upper and lower cases is sealed with a sealant. The sealant is, for example, an adhesive. In other words, the upper and lower cases are joined together by the adhesive. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-57563 [Patent Document 2] Japanese Patent Publication No. 2022-165836 Summary of the Invention [Problem to be solved by the invention]

[0006] When a battery in a battery pack deteriorates, the battery case is opened for replacement, and during the opening process, the adhesive is cut with a cutter.

[0007] If high-voltage parts inside the battery case, such as battery terminals or parts of the power circuit, are close to the flange, the worker must be careful not to insert the cutter blade too far into the case. For example, the worker must insert the cutter so as not to exceed a predetermined upper limit of insertion depth. This can make the opening process complicated.

[0008] Therefore, this specification discloses a battery case connection structure that can prevent the cutting edge of a cutter from entering the battery case when a high-voltage section is disposed close to a flange. [Means for solving the problem]

[0009] This specification discloses a battery case connection structure. This connection structure includes a lower case and an upper case. The lower case includes a tray portion and a lower flange. A plurality of batteries are disposed in the tray portion. The lower flange is disposed on the periphery of the tray portion. The upper case includes a cover portion and an upper flange. The cover portion is placed over the tray portion. The upper flange is disposed on the periphery of the cover portion. The lower flange and the upper flange are sealed with an adhesive. A high-voltage portion is disposed in the tray portion near the lower flange and the upper flange. A rib is formed on the upper flange or the lower flange to separate the adhesive from the high-voltage portion.

[0010] According to the above configuration, the cutting edge of the cutter inserted into the gap between the upper flange and the lower flange abuts against the rib, thereby preventing the cutting edge from entering the interior of the case.

[0011] In the above configuration, a rib may be formed on the lower flange. In this case, the rib is disposed closer to the high-voltage section than the adhesive surface of the lower flange. An adhesive is applied to the adhesive surface. The rib protrudes toward the upper case than the adhesive surface. The lower flange surrounds the entire periphery of the tray portion. The rib is formed on the entire periphery of the lower flange. The adhesive is a liquid adhesive.

[0012] According to the above structure, the ribs prevent the liquid adhesive from entering the inside of the case.

[0013] In the above configuration, a rib may be formed on the lower flange. In this case, the rib is positioned closer to the high-voltage section than the adhesive surface of the lower flange. An adhesive is applied to the adhesive surface. The upper flange and the lower flange have fastening surfaces on the outer edges of the adhesive surfaces. Fastening holes are drilled in the fastening surfaces of the upper flange and the lower flange. A step structure is formed on the upper flange by the fastening surface and the adhesive surface. The fastening surface is positioned closer to the lower flange than the adhesive surface. The protruding height of the rib is less than the step height in the step structure of the upper flange.

[0014] According to the above configuration, the fastening holes of the upper flange and the lower flange are aligned with each other, and when the lower case and the upper case are moved relative to each other for the alignment, the rib of the lower case is prevented from getting caught on the upper case.

[0015] In the above configuration, a rib may be formed on the upper flange. In this case, the rib is disposed closer to the high-voltage section than the adhesive portion of the upper flange. An adhesive is applied to the adhesive portion. The upper flange and the lower flange are provided with fastening portions on the outer edges of the adhesive portion. The fastening portions of the upper flange and the lower flange are fastened to the vehicle frame. The rib has a U-shaped cross section.

[0016] According to the above configuration, the fastening portions of the upper flange and lower flange serve as fastening points to the vehicle body frame. If a rib with a U-shaped cross section were provided on the lower flange, the rib might deform and open due to the weight of the battery. By forming a rib with a U-shaped cross section on the upper flange, the opening deformation of the rib is suppressed. [Effects of the Invention]

[0017] The battery case connection structure disclosed in this specification makes it possible to prevent the cutting edge of the cutter from entering the battery case when the high-voltage section is disposed close to the flange. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 2 is a perspective view illustrating a battery case according to the embodiment and a frame serving as a vehicle skeleton. [Figure 2] FIG. 2 is a perspective view illustrating an example of a battery case according to the present embodiment. [Figure 3] FIG. 2 is a perspective view illustrating a lower case. [Figure 4] 2 is a cross-sectional view taken along the line AA in FIG. 1, illustrating the peripheral structure of an upper flange and a lower flange. [Figure 5] FIG. 5 is a cross-sectional view showing a first modification (small protruding rib) of FIG. 4. [Figure 6] FIG. 5 is a cross-sectional view showing a second modification of FIG. 4 (a rib on the upper flange). DETAILED DESCRIPTION OF THE INVENTION

[0019] 1 to 6 show an example of a connection structure of a battery pack according to this embodiment. A battery case 15 according to this embodiment is mounted on an electric vehicle (BEV).

[0020] In Figures 1 to 6, the front-to-rear direction of the vehicle is indicated by the FR axis. The width direction of the vehicle is indicated by the RW axis. The vertical direction is indicated by the UP axis. The positive direction of the FR axis is the front. The positive direction of the RW axis is the right direction. The positive direction of the UP axis is the height direction.

[0021] FIG. 1 illustrates a frame 90 and a battery case 15 according to this embodiment. The frame 90 is part of the vehicle framework. The frame 90 has a frame shape in plan view. Note that in FIG. 1, the frame 90 is depicted as a single component. Alternatively, the frame 90 may be composed of multiple components. For example, a pair of sub-parts extending in the longitudinal direction of the vehicle and a pair of sub-parts extending in the width direction of the vehicle may be joined by welding or the like.

[0022] For example, the frame 90 is disposed on the floor surface of the vehicle compartment. For example, the frame 90 is disposed at the front end, both side ends, and rear end of the floor surface of the vehicle compartment.

[0023] 4 illustrates an example of a cross-sectional view taken along line AA in FIG. 1. The frame 90 has, for example, a hollow structure. For example, the cross section of the frame 90 is rectangular. That is, the frame 90 has an upper wall 92, a bottom wall 96, and a pair of side walls 94, 94. A fastening hole 96A is drilled in the bottom wall 96 of the frame 90. The fastening hole 96A penetrates the bottom wall 96 in the thickness direction.

[0024] A weld nut 98 is provided inside the frame 90. The weld nut 98 is coaxial with the fastening hole 96A. As will be described later, the fastening holes 34B and 54B of the battery pack 10 are aligned with the fastening hole 96A. Then, bolts 95 (fasteners) are threaded into these fastening holes 34B, 54B, and 96A. This fastens the battery pack 10 to the frame 90.

[0025] 1, battery pack 10 is a large box-shaped component. For example, battery pack 10 is placed on the floor of a vehicle compartment. Battery pack 10 supplies power to a rotating electric machine (not shown) that is a drive source for the vehicle.

[0026] The battery pack 10 is supported by a frame 90. Referring to Figures 1 and 4, for example, a plurality of fastening holes 34B, 54B are drilled in the upper flange 30 and the lower flange 50 of the battery pack 10. The upper flange 30 and the lower flange 50 are formed around the entire periphery of the battery pack 10. The fastening holes 34B, 54B are also formed around the entire periphery of the upper flange 30 and the lower flange 50. Therefore, the battery pack 10 is fastened and supported to the frame 90 around the entire periphery.

[0027] 1 and 4, battery pack 10 includes a battery case 15 and a plurality of batteries 80. Battery case 15 houses batteries 80. Battery 80 is formed of, for example, a nickel-metal hydride secondary battery, a lithium-ion secondary battery, or an all-solid-state battery.

[0028] The battery 80 has, for example, a terminal 82 (high voltage portion) protruding in the vehicle width direction. Within the battery pack 10, for example, the terminal 82, which is the high voltage portion of the battery 80, is disposed near the upper flange 30 and the lower flange 50 of the battery pack 10.

[0029] As will be described later, the upper flange 30 and the lower flange 50 are sealed (bonded) with an adhesive 70. For example, as illustrated in Fig. 4, the terminal 82 and the adhesive 70 are disposed at the same height. The terminal 82 and the adhesive 70 are adjacent to each other in the vehicle width direction, for example, within a range of 5 cm to 20 cm.

[0030] Therefore, as will be described later, the terminal 82 and the adhesive 70 are separated by the rib 60. In other words, the rib 60 serves as a wall that separates the terminal 82 and the adhesive 70. As a result, the cutting edge of the blade 101 of the cutter 100 (see FIG. 2) abuts against the rib 60. In other words, the rib 60 prevents the blade 101 from entering the battery case 15.

[0031] 2, the battery case 15 includes an upper case 20 and a lower case 40. The upper case 20 is a lid portion of the battery case 15. For example, the upper case 20 is made of a metal panel such as an aluminum panel. For example, the upper case 20 is formed by press working.

[0032] The upper case 20 includes a cover portion 22 and an upper flange 30. The cover portion 22 is placed over the tray portion 42 of the lower case 40. The cover portion 22 includes a top wall 24 and a side wall 26. The top wall 24 extends horizontally. The side wall 26 surrounds the entire periphery of the top wall 24. Referring to FIG. 4 , the side wall 26 stands upright relative to the top wall 24.

[0033] An upper flange 30 is disposed on the periphery of the cover portion 22. Referring to Fig. 4, the upper flange 30 is provided at the end (the lower end in Fig. 4) of the side wall 26. The upper flange 30 is provided around the entire periphery of the side wall 26. The upper flange 30 extends horizontally, for example, parallel to the top wall 24.

[0034] The upper flange 30 includes an adhesive portion 32 and a fastening portion 34. The adhesive portion 32 is provided with an adhesive surface 32A. The adhesive surface 32A faces an adhesive surface 52A of the lower flange 50. An adhesive 70 is applied to the adhesive surfaces 32A, 52A.

[0035] The fastening portion 34 is formed on the outer edge of the adhesive portion 32. The fastening portion 34 is provided with a fastening surface 34A. The fastening surface 34A faces the fastening surface 54A of the lower flange 50. The fastening hole 34B is drilled in the fastening surface 34A. The fastening hole 34B penetrates the fastening portion 34 in the thickness direction.

[0036] A step structure is formed by the adhesive portion 32 and the fastening portion 34. That is, the fastening surface 34A is positioned closer to the lower flange 50 than the adhesive surface 32A. When fastened with a bolt 95 (fastener), the fastening surfaces 34A and 54A abut against each other. Meanwhile, the step structure formed by the adhesive portion 32 and the fastening portion 34 separates the adhesive surface 32A from the adhesive surface 52A. This separated space becomes a filling space for the adhesive 70.

[0037] A collar 97 is disposed between the fastening portion 34 and the bottom wall 96 of the frame 90 so that the step structure formed by the adhesive portion 32 and the fastening portion 34 does not interfere with bolt fastening.

[0038] 3 and 4, the lower case 40 includes a tray portion 42 and a lower flange 50. The lower case 40 is made of a metal panel, such as an aluminum panel. For example, the lower case 40 is formed by press working. A plurality of batteries 80 are disposed in the tray portion 42. As described above, the terminals 82 (high-voltage portions) of the batteries 80 are disposed near the lower flange 50.

[0039] The tray portion 42 includes a side wall 44 and a bottom wall 46. The bottom wall 46 extends horizontally. The side wall 44 is provided on the periphery of the bottom wall 46. The side wall 44 stands upright relative to the bottom wall 46. As will be described later, a rib 60 is formed on the upper end of the side wall 44.

[0040] A lower flange 50 is connected to the side wall 44. The lower flange 50 is disposed on the periphery of the tray portion 42. For example, the lower flange 50 surrounds the entire periphery of the tray portion 42. The lower flange 50 extends horizontally from the upper end of the side wall 44 in parallel with the bottom wall 46.

[0041] The lower flange 50 includes an adhesive portion 52, a fastening portion 54, and a rib 60. The fastening portion 54 is formed on the outer edge of the adhesive portion 52. The adhesive portion 52 and the fastening portion 54 may be formed on the same plane. By arranging the adhesive portion 52 and the fastening portion 54 on the same plane, a blade 101 (see FIG. 2), which will be described later, can smoothly reach the adhesive 70.

[0042] The adhesive portion 52 has an adhesive surface 52A. An adhesive 70 is applied to the adhesive surface 52A. For example, as illustrated in FIG. 3, the adhesive surface 52A may be colored. When the adhesive portion 52 and the fastening portion 54 are formed on the same plane, the adhesive surface 52A can be easily identified by making the adhesive surface 52A a colored region.

[0043] The fastening portion 54 is provided with a fastening surface 54A. The fastening surface 54A faces the fastening surface 34A of the upper flange 30. A fastening hole 54B is drilled in the fastening surface 54A. The fastening hole 54B penetrates the fastening portion 54 in the thickness direction.

[0044] When sealing (joining) the upper case 20 and the lower case 40, adhesive 70 is applied to the adhesive surface 52A. The adhesive 70 is, for example, a liquid adhesive. That is, the liquid adhesive 70 is applied to the adhesive surface 52A. The upper case 20 is then placed over the lower case 40. At this time, the adhesive surface 32A of the upper case 20 faces the adhesive surface 52A, squeezing the adhesive 70. In this state, the adhesive 70 hardens. Note that in the process of placing the upper case 20 over the lower case 40, the axes of the fastening holes 34B and 54B are aligned.

[0045] The upper case 20 and the lower case 40 are joined together by hardening of the adhesive 70. The adhesive 70 also seals the gap between the upper flange 30 and the lower flange 50 around the entire periphery. In other words, the battery 80 is enclosed within the battery case 15.

[0046] 3 and 4, a rib 60 is formed on the lower flange 50. The rib 60 is formed around the entire periphery of the lower flange 50. As illustrated in FIG. 4, for example, the rib 60 is a protrusion with a U-shaped cross section. The rib 60 is formed by, for example, press molding. By forming the rib 60 on the lower flange 50, the strength of the lower flange 50 is improved.

[0047] The rib 60 separates the adhesive 70 from the terminal 82 (high voltage portion). For example, the rib 60 is disposed closer to the terminal 82 (high voltage portion) than the adhesive surface 52A. With reference to Fig. 4, for example, the rib 60 is formed at the connection (boundary) between the lower flange 50 and the side wall 44.

[0048] The rib 60 protrudes toward the upper case 20 beyond the adhesive surface 52A. Furthermore, the rib 60 may protrude toward the top wall 24 beyond the adhesive surface 32A of the upper case 20. For example, as illustrated in FIG. 4, the side wall 44 of the lower case 40 is disposed more inward in the vehicle width direction than the side wall 26 of the upper case 20. The rib 60 is formed in the gap between the side walls 26, 44.

[0049] 2 and 4, when the battery 80 in the battery pack 10 deteriorates, the battery case 15 is opened and the battery 80 is replaced. During this opening operation, the adhesive 70 is cut by a cutter 100.

[0050] Cutter 100 is also called a windshield remover. Cutter 100 includes blade 101, lever 102, and handle 103. When bolt 95 is removed from battery pack 10, a gap is created between fastening surface 34A and fastening surface 54A. Blade 101 is inserted into this gap. With blade 101 piercing adhesive 70, lever 102 is pulled along upper flange 30 and lower flange 50. This cuts adhesive 70.

[0051] When the blade 101 pierces the adhesive 70 and is inserted further, the cutting edge of the blade 101 abuts against the rib 60. In other words, the rib 60 is used as a guide for the insertion depth of the blade 101.

[0052] Furthermore, the rib 60 separates the adhesive 70 from the high-voltage portion (terminal 82) inside the battery case 15. In other words, the rib 60 prevents the cutting edge of the blade 101 from entering the battery case 15.

[0053] The rib 60 also functions as a blocking plate for the adhesive 70. Referring to FIG. 3, the rib 60 is formed around the entire periphery of the lower flange 50. For example, the height of the rib 60 is uniform around the entire periphery. If the adhesive 70 is a liquid adhesive, when the upper case 20 is placed over the lower case 40, the liquid (i.e., pre-hardened) adhesive 70 is crushed. At this time, the rib 60 stops the movement of the adhesive 70. As a result, the adhesive 70 is prevented from entering the battery case 15.

[0054] <Small protruding rib> Figure 5 shows a first alternative example of the joining structure of the battery case 15 according to this embodiment. In this example, the side wall 26 of the upper case 20 and the side wall 44 of the lower case 40 are arranged on a vertical line. Furthermore, the rib 60 is formed to have a small protrusion compared to the embodiment in Figure 4. The other configurations are the same as those in Figure 4, and therefore will not be described below as appropriate.

[0055] Furthermore, a rib 60 is formed on the lower flange 50. The rib 60 separates the adhesive 70 from the terminal 82 (high voltage portion). That is, the rib 60 is disposed closer to the terminal 82 (high voltage portion) than the adhesive surface 52A. For example, the rib 60 is formed at the connection portion between the side wall 44 and the lower flange 50.

[0056] An enlarged view is shown in the lower right of Figure 5. The rib 60 protrudes toward the upper case 20 beyond the bonding surface 52A. Meanwhile, the rib 60 terminates just before the bonding surface 32A of the upper case 20. In other words, the protruding height H2 of the rib 60 is less than the height H1 of the step between the bonding surface 32A and the fastening surface 34A of the upper flange 30.

[0057] By forming the ribs 60 as small protrusions in this manner, interference between the ribs 60 and the upper case 20 can be avoided. For example, contact between the ribs 60 and the side walls 26 of the upper case 20 can be avoided.

[0058] As described above, the upper case 20 and the lower case 40 are moved relative to each other to align the axes of the fastening holes 34B, 54B. At this time, interference between the rib 60 and the upper case 20 is avoided, allowing the upper case 20 and the lower case 40 to move smoothly relative to each other.

[0059] <Ribs on the upper case> 6 shows a second example of the joining structure of the battery case 15 according to this embodiment. In this example, a rib 60 is formed on the upper flange 30 instead of the lower flange 50. The rest of the configuration is the same as in FIG. 4, and therefore, the description below will be omitted as appropriate.

[0060] The rib 60 separates the adhesive 70 from the terminal 82 (high voltage portion). That is, the rib 60 is disposed closer to the terminal 82 (high voltage portion) than the adhesive surface 32A. For example, the rib 60 is formed at the connection portion between the side wall 26 and the upper flange 30.

[0061] Rib 60 protrudes toward lower case 40 beyond adhesive surface 32A. Furthermore, rib 60 protrudes toward bottom wall 46 beyond adhesive surface 52A of lower flange 50. By having rib 60 protrude downward beyond adhesive surface 52A, blade 101 (see FIG. 2) can be reliably stopped.

[0062] Furthermore, the rib 60 may have a U-shaped cross section. When the fastening portions 34, 54 are fastened to the frame 90, the weight of the battery 80 or the like may cause the tray portion 42 and the lower flange 50 to bend. For example, if the lower case 40 is formed with a U-shaped cross section rib 60, the rib 60 may open due to the above-mentioned bending. By forming the rib 60 on the upper flange 30, the opening of the rib 60 is suppressed.

[0063] <Other variations> In the above-described embodiment, the rib 60 is formed on only one of the upper flange 30 and the lower flange 50. Alternatively, the rib 60 may be formed on both the upper flange 30 and the lower flange 50.

[0064] Moreover, the ribs 60 are provided around the entire periphery of the upper flange 30 or the lower flange 50. Alternatively, the ribs 60 may be formed only on a portion of the upper flange 30 or the lower flange 50. For example, the ribs 60 may be formed only in locations where high-voltage parts such as terminals 82 are located near the upper flange 30 and the lower flange 50. [Explanation of symbols]

[0065] 10 battery pack, 15 battery case, 20 upper case, 22 cover portion, 30 upper flange, 32, 52 adhesive portion, 32A, 52A adhesive surface, 34, 54 fastening portion, 34A, 54A fastening surface, 34B, 54B fastening hole, 40 lower case, 42 tray portion, 50 lower flange, 60 rib, 70 adhesive, 80 battery, 82 terminal (high voltage portion), 90 frame, 95 volts, 100 cutter.

Claims

1. a lower case including a tray portion in which a plurality of batteries are arranged and a lower flange arranged on the periphery of the tray portion; an upper case including a cover portion that covers the tray portion and an upper flange that is disposed on a periphery of the cover portion; wherein the lower flange and the upper flange are sealed with an adhesive. A battery case connection structure, a high-voltage unit is disposed in the tray unit near the lower flange and the upper flange; The upper flange or the lower flange is formed with a rib that separates the adhesive from the high-voltage portion. Battery case joining structure.

2. The battery case connection structure according to claim 1, The rib is formed on the lower flange, the rib is disposed closer to the high-voltage portion than the adhesive surface of the lower flange, to which the adhesive is applied; the rib protrudes toward the upper case beyond the adhesive surface, The lower flange surrounds the entire periphery of the tray portion, The rib is formed around the entire periphery of the lower flange, The adhesive is a liquid adhesive. Battery case joining structure.

3. The battery case connection structure according to claim 1, The rib is formed on the lower flange, the rib is disposed closer to the high-voltage portion than the adhesive surface of the lower flange, to which the adhesive is applied; the upper flange and the lower flange have fastening surfaces on outer edges of the adhesive surfaces, Fastening holes are drilled in the fastening surfaces of the upper flange and the lower flange, a step structure is formed on the upper flange by the fastening surface and the adhesive surface, and the fastening surface is disposed closer to the lower flange than the adhesive surface; The protruding height of the rib is less than the step height of the step structure of the upper flange. Battery case joining structure.

4. The battery case connection structure according to claim 1, The rib is formed on the upper flange, the rib is disposed closer to the high voltage portion than the adhesive portion of the upper flange, where the adhesive is applied; The upper flange and the lower flange have fastening portions at outer edges of the adhesive portions, the fastening portions of the upper flange and the lower flange are fastened to a vehicle frame, The rib has a U-shaped cross section. Battery case joining structure.

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