Cover Structure

Abstract

To inhibit a liquid from directly spilling on a gas discharge part and enable smooth emission of a gas discharged from the gas discharge part.SOLUTION: A cover structure includes: a gas discharge part which discharges a gas generated in a housing of a vehicular battery pack; and a cover member which is provided so as to cover the gas discharge part. A first opening which is open upward is formed between an upper edge part of the cover member and an upper area, extending at the upper side of the gas discharge part, of a side surface of the housing.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a cover structure. [Background technology]

[0002] Patent Document 1 below discloses a secondary battery case having a case body that seals a positive electrode, a negative electrode, and an electrolyte therein, and a safety valve that is provided in the case body and ruptures when the internal pressure of the case body reaches a predetermined pressure, thereby releasing the internal pressure of the case body to the outside. The safety valve is configured with a thin-walled portion that is thinner than the case body and has a dome shape that bulges inward from the case body. In addition, a rupture groove that ruptures when the internal pressure of the case body reaches a predetermined pressure is provided on only one surface in the thickness direction of the thin-walled portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5990064 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a vehicle battery pack equipped with a gas exhaust section for exhausting gas generated within the housing and releasing the gas outside the vehicle, when the vehicle is washed with a high-pressure car washer or when the vehicle is driven on a wet road, there is a risk that water with high dynamic water pressure or liquid such as cleaning fluid will be sprayed toward the gas exhaust section, and the liquid may come into direct contact with the gas exhaust section.

[0005] An object of the present invention is to prevent liquid from directly splashing on the gas discharge portion and to enable smooth release of gas discharged from the gas discharge portion. [Means for solving the problem]

[0006] A cover structure according to one aspect of the present invention includes a gas exhaust section that exhausts gas generated inside a housing of a vehicle battery pack, and a cover member that is provided to cover the gas exhaust section. A first opening that opens upward is formed between an upper edge of the cover member and an upper region of a side surface of the housing that extends above the gas exhaust section. [Effects of the Invention]

[0007] According to the present invention, it is possible to prevent liquid from directly splashing on the gas discharge portion, and also to enable smooth release of gas discharged from the gas discharge portion. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram for explaining the cover structure according to the embodiment, and is a schematic partial rear view showing the arrangement relationship of the vehicle battery pack, the gas exhaust portion, and the cover member in the vehicle. [Figure 2] FIG. 10 is a diagram for explaining the cover structure according to the embodiment, and is a schematic partial rear view showing the arrangement of the gas discharge portion and the cover member on the left side in the vehicle width direction at the rear side of the vehicle battery pack. [Figure 3] 1 is a partial plan view showing the structure of a lower case of a vehicle battery pack in a cover structure according to an embodiment; [Figure 4] FIG. 2 is a partial perspective view showing the structure of a lower case of a vehicle battery pack in a cover structure according to an embodiment. [Figure 5] 1 is a partial perspective view showing the arrangement of a lower case and a gas discharge portion in a cover structure according to an embodiment; [Figure 6] 5 is a partial perspective view showing the arrangement of the lower case, the gas exhaust section, and the cover member on the left side in the vehicle width direction at the rear of the vehicle battery pack in the cover structure according to the embodiment, and shows the state in which the gas exhaust section in FIG. 5 is covered with the cover member. [Figure 7]7 is a partial cross-sectional view taken along line AA in FIG. 6, showing the arrangement of the lower case, the gas discharge portion, and the cover member in a normal state on the left side in the vehicle width direction at the rear side of the vehicle battery pack of the cover structure according to the embodiment. [Figure 8] 8 is a partial cross-sectional view corresponding to FIG. 7, showing the arrangement of the lower case, gas discharge portion, and cover member in a high-pressure state on the left side in the vehicle width direction of the vehicle rear side of the vehicle battery pack in the cover structure according to the embodiment. [Figure 9] 10 is a partial rear view of the cover structure according to the embodiment, showing the arrangement of the lower case and the gas discharge portion on the left side in the vehicle width direction on the vehicle rear side of the vehicle battery pack. FIG. [Figure 10] 10 is a partial rear view showing the arrangement of the lower case, the gas exhaust section, and the cover member on the left side in the vehicle width direction at the rear of the vehicle battery pack of the cover structure according to the embodiment, and shows the state in which the gas exhaust section according to FIG. 9 is covered with the cover member. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a cover structure according to an embodiment will be described with reference to the drawings. In each drawing, FR and RR indicate the front and rear in the longitudinal direction of the vehicle, LH and RH indicate the left and right in the width direction of the vehicle, and UP and DN indicate the upper and lower in the vertical direction of the vehicle. The center of the vehicle in the width direction is referred to as the inner side in the vehicle width direction, and the opposite side to the inner side in the width direction is referred to as the outer side in the vehicle width direction. In each drawing, the inner side in the vehicle width direction is indicated by IS, and the outer side in the width direction is indicated by OS. In the following description, the front and rear in the longitudinal direction of the vehicle, and the upper and lower sides in the vertical direction of the vehicle will be simply referred to as the "front of the vehicle," "rear of the vehicle," "upper," and "lower," respectively. Elements having the same function will be assigned the same symbols, and duplicate explanations will be omitted.

[0010] The cover structure according to the embodiment is used, for example, in a vehicle battery pack 1 shown in Fig. 1 that supplies driving power to a vehicle V, which is an electric vehicle driven by an electric motor (not shown). The vehicle battery pack 1 is disposed on the lower side of the vehicle V.

[0011] As shown in Fig. 2, a gas exhaust unit 10 that exhausts gas generated inside the housing 5 is disposed on one of the side surfaces 9 of the housing 5 of the vehicle battery pack 1, the side surface facing the rear of the vehicle. When gas is generated from the battery module built into the housing 5, the gas is exhausted from the gas exhaust unit 10 to the outside of the vehicle V.

[0012] The vehicle battery pack 1 has a housing 5 as an exterior member that houses a battery module (not shown). The housing 5 has a hollow rectangular box shape and houses a battery module with one or more built-in cells inside. The illustrated housing 5 has a flat shape in which the overall dimension in the vertical direction of the vehicle is smaller than the dimensions in the longitudinal direction or width direction of the vehicle. The shape of the housing 5 can be appropriately set depending on the shape and dimensions of the vehicle battery pack 1, the installation method in the vehicle, etc. The housing 5 may also house auxiliary equipment (not shown), such as a controller, switch, relay, etc., that manages the capacity, voltage, temperature, etc. of the battery module.

[0013] The housing 5 includes an upper case 6 and a lower case 7. The upper case 6 and the lower case 7 are fastened together at their peripheral edges via fasteners such as bolts (not shown). A sealing member (not shown) made of a rubber material or the like may be interposed at the contact area between the upper case 6 and the lower case 7. The vehicle battery pack 1 is fixed to the vehicle V by fastening the peripheral edges of the housing 5 to vehicle body frame members (not shown), such as side members and cross members, via fasteners such as bolts (not shown).

[0014] As shown in Figures 3 and 4, the lower case 7 is a box-shaped member with a bottom that is open at the top and has a substantially rectangular shape in a plan view. One or more battery modules are disposed on the bottom 70 of the lower case 7. Furthermore, in the area of ​​the lower case 7 toward the rear of the vehicle, the battery modules may be stacked two or more levels above and below. As illustrated in the figures, a partition 60 may be provided to separate the multiple battery modules, dividing the bottom 70. This can prevent the battery modules from coming into contact with each other when an external force is applied to the vehicle battery pack 1. Wiring members such as bus bars (not shown) are disposed between the multiple battery modules to electrically connect the battery modules to each other.

[0015] The upper case 6 is a plate-like member having a substantially rectangular shape in a plan view. The upper case 6 closes the upper opening of the lower case 7, thereby sealing the interior of the housing 5. Furthermore, a bulge portion that bulges out more toward the top of the vehicle than the front area of ​​the vehicle may be formed in the region of the upper case 6 on the vehicle rear side, depending on the number of battery modules arranged in the lower case 7. This allows more battery modules to be arranged on the vehicle rear side, making the vehicle battery pack 1 thinner overall and more space-saving, while ensuring greater battery capacity.

[0016] The lower case 7 includes a peripheral wall 8 that horizontally separates the interior and exterior of the housing 5. At least a portion of the peripheral wall 8 has a hollow cross-section and a substantially rectangular cross-sectional shape. More specifically, as shown in FIGS. 3, 4, 7, and 8, the peripheral wall 8 includes an outer wall 8a that extends from the bottom 70 of the lower case 7 and constitutes the side surface 9 of the housing 5, and an inner wall 8b that extends toward the interior of the housing relative to the outer wall 8a. A gap is formed between the outer wall 8a and the inner wall 8b, and this gap extends from the front side of the vehicle to the rear side of the vehicle, forming a gas exhaust channel 8c. For example, when gas is generated from the battery module, the gas flows into the gas exhaust channel 8c from a gas exhaust channel inlet 8d located on the front side of the vehicle inside the housing 5, as indicated by arrow B in FIG. 3. The gas flows through the gas exhaust channel 8c and is discharged to the rear of the vehicle battery pack 1 via a gas exhaust unit 10 (described later).

[0017] 5 to 10, in the cover structure according to the embodiment, the vehicle battery pack 1 includes a gas discharge portion 10, a cover member 20, and a first opening 30. In FIGS. 5 to 10, the left side in the vehicle width direction corresponds to the outer side in the vehicle width direction, and the right side in the vehicle width direction corresponds to the inner side in the vehicle width direction.

[0018] The gas exhaust unit 10 is disposed on a side surface 9 of the housing 5 of the vehicle battery pack 1 and exhausts gas generated inside the housing 5. As shown in FIG. 2, the gas exhaust unit 10 is disposed on one of the side surfaces 9 of the housing 5 that is located on the vehicle rear side, below the extending wall portion 5a. The extending wall portion 5a is a wall portion that extends horizontally from the peripheral edge of the housing 5, and is, for example, a flange that extends horizontally from the peripheral edge of the upper case 6 or the lower case 7. Also, as shown in FIG. 1, the gas exhaust unit 10 is disposed on each of the left and right sides in the vehicle width direction of the side surface 9 that is located on the vehicle rear side. Furthermore, the rear wheels W of the vehicle V are disposed near the outer sides of each of the gas exhaust units 10 in the vehicle width direction.

[0019] 7 and 8, the gas discharge section 10 includes an opening 11 and a valve body 12. The opening 11 is provided on the vehicle rear side of the outer wall portion 8a of the housing 5. The opening 11 opens toward the vehicle rear and has a substantially circular cross section. The valve body 12 is inserted into the opening 11 from the vehicle rear and closes the opening 11. The valve body 12 has a substantially circular shape that is larger than the opening 11 when viewed in the vehicle front-rear direction.

[0020] 5 and 9, the valve body 12 may have a seal portion 14 on its outer peripheral edge portion 12a. The seal portion 14 is made of an elastic material such as rubber, and in one embodiment may be made of EPDM (ethylene propylene diene rubber). By providing the seal portion 14, the opening 11 can be closed more reliably by the valve body 12.

[0021] 7, in the normal state, the opening 11 is closed by the valve body 12. In other words, the gas exhaust unit 10 is in a closed state, i.e., a closed valve state, and the inside and outside of the housing 5 are separated by the gas exhaust unit 10. The normal state is a state in which no gas is generated inside the housing 5 and the internal pressure is lower than a specified value.

[0022] When the pressure is increased, the valve element 12 moves outward from the housing as shown in Figure 8, forming a gap between the periphery of the opening 11 and the valve element 12. At this time, the gas discharge part 10 is in an open state, that is, an open valve state. The high pressure state is a state in which gas is generated inside the housing 5 and the internal pressure of the housing 5 rises to a specified value or higher. The horizontal direction from the outside of the housing 5 to the inside is referred to as the inside of the housing, and the direction opposite to the inside of the housing is referred to as the outside of the housing.

[0023] In the open valve state, the inside and outside of the housing 5 are connected via the gas exhaust unit 10, and therefore, as shown by arrows C and D in Fig. 8, gas generated inside the housing is exhausted from the gas exhaust unit 10 to the outside of the vehicle. As the gas is exhausted, the internal pressure of the housing 5 decreases and returns to the normal state. Then, the valve element 12 moves inward of the housing, and the housing returns to the closed valve state shown in Fig. 7.

[0024] In this way, the valve element 12 is configured to be movable toward the rear of the vehicle, that is, outside the housing 5 relative to the side surface 9 of the housing 5. The gas discharge unit 10 is configured to be switchable between a closed valve state and an open valve state by the movement of the valve element 12.

[0025] In one embodiment, such a valve element 12 can be configured by providing a plurality of spring plates (not shown) extending radially outward from the end of the valve element 12 on the gas discharge passage 8c side. The spring plates are made of, for example, metal or resin and are elastically deformable. In a normal state, the spring plates abut against the area surrounding the opening 11 on the gas discharge passage 8c side, fixing the valve element 12 to the opening 11 and establishing a closed valve state. In a high-pressure state, the spring plates elastically deform, moving the valve element 12 toward the rear of the vehicle and establishing an open valve state. After discharging gas in the open valve state, the elastic restoring force of the spring plates moves the valve element 12 toward the front of the vehicle, and the valve is again established in a closed valve state.

[0026] The position of the gas discharge unit 10 is not limited to the example shown in the figure. For example, the gas discharge unit 10 may be provided on the left side surface of the housing 5 in the vehicle width direction or on the right side surface of the housing 5 in the vehicle width direction. In this case, the valve body 12 is movable to the left or right in the vehicle width direction, which is outward from the side surface 9 of the housing 5. In other words, the valve body 12 is configured to move outward from the side surface 9 of the housing 5 to discharge gas.

[0027] The shape or dimensions of the gas discharge section 10 can be set appropriately depending on the size and shape of the vehicle battery pack 1, the mounting position and mounting method of the vehicle battery pack 1 on the vehicle body V, etc. In one embodiment, the gas discharge section 10 may be configured by closing the opening 11 with a flat plate that is thinner than the outer wall section 8a of the housing 5. In that case, when the internal pressure of the housing 5 reaches or exceeds a specified value, the gas discharge section 10 ruptures, allowing the gas to be discharged.

[0028] As shown in FIG. 6 or 10 , the gas exhaust unit 10 is covered by a cover member 20 when viewed in the vehicle longitudinal direction. In other words, the cover member 20 is provided on the side surface 9 of the housing 5 so as to cover the gas exhaust unit 10. The cover member 20 is a plate member having a substantially rectangular shape when viewed in the vehicle longitudinal direction, and may be made of a metal such as iron or aluminum, or a resin. Note that the cover member 20 shown in FIG. 1 covers the gas exhaust units 10 disposed on the left and right sides of the side surface 9 that is located rearward of the vehicle, in the vehicle width direction. In the illustrated example, the cover members 20 have shapes that are line-symmetrical to each other with respect to the vertical axis.

[0029] A flange portion 22 extending from the peripheral edge along the side surface 9 may be formed on the peripheral edge of the cover member 20. In the illustrated example, the cover member 20 includes the flange portion 22 extending from the bottom wall portion 21b or the side wall portions 21c, 21d along the side surface 9, and the flange portion 22 abuts against the side surface 9. The cover member 20 is positioned relative to the side surface 9 via the flange portion 22 by a positioning member such as a positioning pin, and is fixed by a fastener such as a bolt. The cover member 20 may also be fixed to the side surface 9 by adhering the flange portion 22 to the side surface 9.

[0030] The cover member 20 has an opposing wall portion 21. The opposing wall portion 21 faces at least the gas discharge portion 10 of the side surface 9 in the vehicle longitudinal direction. The opposing wall portion 21 is an area surrounded by an upper edge portion 20a, a lower edge portion 20b, a side edge portion 20c, and a side edge portion 20d. As shown in FIGS. 7 and 8 , the opposing wall portion 21 and the gas discharge portion 10 are spaced apart so as to be out of contact with each other. Therefore, a space S is interposed between the opposing wall portion 21 and the gas discharge portion 10. In other words, the opposing wall portion 21 is a wall portion of the side surface 9 of the housing 5 that is spaced apart from the gas discharge portion 10 and faces at least the gas discharge portion 10.

[0031] In the illustrated example, the upper edge 20a of the opposing wall 21 is located higher than the upper end 10a, which is the uppermost part of the gas discharge section 10. The lower edge 20b of the opposing wall 21 is located lower than the lower end 10b, which is the lowest part of the gas discharge section 10. The side edge 20c on the inner side in the vehicle width direction of the opposing wall 21 is located more inward in the vehicle width direction than the side end 10c of the gas discharge section 10, which is the most inward in the vehicle width direction. The side edge 20d on the outer side in the vehicle width direction of the opposing wall 21 is located more outward in the vehicle width direction than the side end 10d of the gas discharge section 10, which is the most outward in the vehicle width direction.

[0032] The cover member 20 has a lower wall portion 21b extending between a lower edge portion 20b and a lower region 9b of the side surface 9 of the housing 5 that extends below the gas discharge portion 10. In the illustrated example, the lower side of the cover member 20 is bent toward the side surface 9 to form the lower wall portion 21b.

[0033] The form of the lower wall portion 21b is not limited to the example shown in the drawings. For example, the lower wall portion 21b may be provided in a vertical position in the lower region 9b of the side surface 9 toward the lower edge portion 20b. In other words, the lower wall portion 21b is a wall portion provided between the lower edge portion 20b and the lower region 9b.

[0034] A second opening 40 that opens downward is formed between the lower edge portion 20b and the lower region 9b. The lower wall portion 21b is formed below the gas discharge portion 10 so as to be continuous with the second opening 40. In the illustrated example, a gap is formed between a portion of the lower edge portion 20b and the lower region 9b, so that the second opening 40, which is a downward opening that communicates with the space S, is formed adjacent to the lower wall portion 21b. The lower wall portion 21b may be disposed outward in the vehicle width direction, and the second opening 40 may be disposed inward in the vehicle width direction. The lower wall portion 21b may be configured to slope downward toward the second opening 40. The second opening 40 may be formed by opening a portion of the lower wall portion 21b downward.

[0035] A side wall portion 21c is interposed between the side edge portion 20c and the side region 9c, and a side wall portion 21d is interposed between the side edge portion 20d and the side region 9d. The side regions 9c and 9d are regions of the side surface 9 that extend laterally of the gas discharge portion 10. As in the illustrated example, the side wall portion 21c may be formed by bending the inner side of the cover member 20 in the vehicle width direction toward the side surface 9. Alternatively, the side wall portion 21d may be formed by bending the outer side of the cover member 20 in the vehicle width direction toward the side surface 9.

[0036] As shown in the figure, bottom wall portion 21b and side wall portion 21d may be connected by curved wall portion 21e that is curved at a predetermined radius of curvature. By providing curved wall portion 21e, bottom wall portion 21b and side wall portion 21d as a whole form a wall portion that includes a curved wall that is curved at a predetermined radius of curvature. In one embodiment, bottom wall portion 21b and side wall portion 21c may be connected by curved wall portion 21e.

[0037] 7 and 8, an inclined surface 16 that slopes downward toward the second opening 40 may be formed in the lower region 9b of the side surface 9. In the example shown, the inclined surface 16 slopes downward toward the lower wall portion 21b and the second opening 40.

[0038] A first opening 30 that opens upward is formed between the upper edge 20a and an upper region 9a of the side surface 9 of the housing 5 that extends above the gas exhaust portion 10. In the illustrated example, the first opening 30, which is an upward opening that communicates with the space S, is formed by separating the upper edge 20a and the upper region 9a to provide a gap. Furthermore, since the upper edge 20a faces the extending wall portion 5a of the housing 5 in the vehicle vertical direction, the opening cross section of the first opening 30 and the extending wall portion 5a of the housing 5 overlap when viewed in the vehicle vertical direction. Furthermore, the opening area of ​​the second opening 40 is configured to be smaller than the opening area of ​​the first opening 30.

[0039] An upper wall portion (not shown) may be interposed between the upper edge portion 20a and the upper region 9a. For example, an upper wall portion extending between the upper edge portion 20a and the upper region 9a may be provided by bending the upper side of the cover member 20 toward the upper region 9a of the side surface 9. In such a case, the first opening 30 is disposed between the upper edge portion 20a and the upper region 9a so as to be continuous with the upper wall portion.

[0040] The opposing wall portion 21 may include a third opening 50. At least a portion of the third opening 50 may be disposed more inward than the outer peripheral edge 12a of the valve body 12 when viewed in the axial direction parallel to the movement direction of the valve body 12. In the illustrated example, since the valve body 12 is movable toward the rear of the vehicle, multiple third openings 50 that open toward the rear of the vehicle are formed so that at least a portion of them is located more inward than the outer peripheral edge 12a of the valve body 12 when viewed in the vehicle longitudinal direction. Note that there may be only one third opening 50.

[0041] The shape or dimensions of the cover member 20 can be set appropriately depending on the shape and dimensions of the gas discharge part 10 or the side surface 9 of the housing 5.

[0042] The following describes the effects of the cover structure according to the embodiment.

[0043] (1) The cover structure according to the embodiment includes a gas exhaust section 10 disposed on a side surface 9 of a housing 5 of a vehicle battery pack 1, which exhausts gas generated within the housing 5, and a cover member 20 provided on the side surface 9 of the housing 5 so as to cover the gas exhaust section 10. A first opening 30 that opens upward is formed between an upper edge portion 20a of the cover member 20 and an upper region 9a of the side surface 9 of the housing 5 that extends above the gas exhaust section 10.

[0044] Therefore, the gas discharge unit 10 is covered by the cover member 20, and even if liquid such as water with high hydrodynamic pressure or cleaning liquid is sprayed toward the gas discharge unit 10 when washing the vehicle V by spraying cleaning liquid onto it or when the vehicle V is running on a wet road, the liquid can be prevented from directly contacting the gas discharge unit 10. Furthermore, when gas is discharged from the gas discharge unit 10, the gas is released from the first opening 30, for example, as shown by arrow C in Fig. 8, so as to prevent an increase in pressure in the space S between the side surface 9 of the housing 5 of the vehicle battery pack 1 and the cover member 20. In other words, the cover structure according to the embodiment can prevent liquid from directly contacting the gas discharge unit 10 and enable smooth release of the gas discharged from the gas discharge unit 10.

[0045] The opening cross section of the first opening 30 and the extending wall portion 5a of the housing 5 may face each other when viewed in the vertical direction of the vehicle. This allows the extending wall portion 5a to block liquid flowing down from above toward the first opening 30. This makes it possible to prevent liquid from entering the space S through the first opening 30.

[0046] (2) In the cover structure according to the embodiment, a second opening 40 that opens downward is formed between the lower edge 20b of the cover member 20 and a lower region 9b of the side surface 9 of the housing 5 that extends below the gas exhaust section 10, and a lower wall portion 21b that is formed to be continuous with the second opening 40 is provided below the gas exhaust section 10.

[0047] Therefore, even if liquid with high hydrodynamic pressure is injected toward the gas discharge portion 10 from below the vehicle V, for example, when the vehicle V is lifted and a cleaning liquid is sprayed from below to wash the vehicle, or when the vehicle V is traveling on a wet road, the liquid is blocked by the lower wall portion 21b and prevented from directly spraying on the gas discharge portion 10. This more reliably prevents the liquid from directly spraying on the gas discharge portion 10. Furthermore, even if liquid enters the space S, the liquid can be released from the second opening 40 as shown by the arrow E in FIG.

[0048] The gas discharge unit 10 may be disposed on one of the side surfaces 9 of the housing 5 that is closer to the rear of the vehicle, and the lower wall portion 21b may be disposed outward in the vehicle width direction than the second opening 40. When the vehicle V runs on a wet road surface, liquid with high hydrodynamic pressure may be ejected from the rear wheels W toward the gas discharge unit 10. In such a case, even if liquid is ejected toward the gas discharge unit 10 from below and outward in the vehicle width direction, the liquid is blocked by the lower wall portion 21b. This more reliably prevents the liquid from directly splashing on the gas discharge unit 10.

[0049] (3) In the cover structure according to the embodiment, the opening area of ​​the second opening 40 is smaller than the opening area of ​​the first opening 30 .

[0050] This more reliably prevents liquid with high hydrodynamic pressure injected from below the vehicle V from directly hitting the gas discharge portion 10, and also more reliably discharges gas generated inside the housing 5 of the vehicle battery pack 1 from the first opening 30. Furthermore, even if liquid enters the space S, the liquid can be discharged from the second opening 40.

[0051] (4) In the cover structure according to the embodiment, the lower wall portion 21b is inclined downward toward the second opening 40.

[0052] Therefore, even if liquid enters the space S, the liquid flows along the slope of the lower wall portion 21b toward the second opening 40. Therefore, the liquid can be more reliably released from the second opening 40.

[0053] Note that side walls 21c, 21d may be interposed between side edge portions 20c, 20d and side regions 9c, 9d, and bottom wall portion 21b and side walls 21c, 21d may be connected by curved wall portion 21e. As a result, even if liquid enters space S, the liquid will flow via side walls 21c, 21d or curved wall portion 21e to bottom wall portion 21b, and further flow along bottom wall portion 21b to second opening 40. Therefore, the liquid can be more reliably released from second opening 40.

[0054] Note that an inclined surface 16 that slopes downward toward the second opening 40 may be formed in the lower region 9b of the side surface 9. This allows the liquid to flow along the inclined surface 16 toward the second opening 40 even if the liquid enters the space S. Therefore, the liquid can be more reliably released from the second opening 40.

[0055] (5) In the cover structure according to the embodiment, the gas discharge unit 10 includes a valve body 12 configured to move outward relative to a side surface 9 of the housing 5 to discharge gas. The opposing wall portion 21 of the cover member 20, which is spaced apart from the gas discharge unit 10 and faces at least the gas discharge unit 10 on the side surface 9 of the housing 5, includes a third opening 50. At least a portion of the third opening 50 is disposed inside an outer peripheral edge portion 12a of the valve body 12 when viewed in the axial direction parallel to the movement direction of the valve body 12.

[0056] Therefore, when gas is discharged from the gas discharge portion 10, the gas can be released from the third opening 50, as shown by arrow D in Fig. 8. This allows the gas to be released more smoothly. Furthermore, even if a liquid with high hydrodynamic pressure is injected toward the gas discharge portion 10, the liquid is blocked by the opposing wall portion 21 of the cover member 20. This more reliably prevents the liquid from directly contacting the outer peripheral edge portion 12a of the valve body 12.

[0057] In the above embodiment, an electric vehicle has been described as an example, but it goes without saying that the cover structure according to the embodiment can also be applied to a vehicle battery pack that supplies power for driving a hybrid vehicle. [Explanation of symbols]

[0058] 1. Vehicle battery pack 5. Cabinet 9 Side 9a Upper area 9b Lower area 10 Gas exhaust section 12 Valve body 12a Outer edge 20 Cover member 20a Shangyube 20b Lower part 21 facing the wall 21b Lower wall portion 30 First opening 40 Second opening 50 Third opening

Claims

1. a gas exhaust section disposed on a side surface of a housing of the vehicle battery pack, which exhausts gas generated within the housing; a cover member provided on a side surface of the housing so as to cover the gas exhaust portion; Equipped with a first opening that opens upward is formed between an upper edge portion of the cover member and an upper region of the side surface of the housing that extends above the gas exhaust portion; a second opening portion that opens downward is formed between a lower edge portion of the cover member and a lower region of the side surface of the housing that extends below the gas discharge portion, The opening area of ​​the second opening is smaller than the opening area of ​​the first opening. Cover structure for the gas exhaust section of a vehicle battery pack.

2. A cover structure as described in Claim 1, wherein a lower wall portion formed to connect with the second opening is provided below the gas exhaust portion.

3. The cover structure according to claim 2 , wherein the lower wall portion slopes downwardly toward the second opening.

4. A gas exhaust section disposed on a side surface of a housing of a vehicle battery pack for exhausting gas generated within the housing; a cover member provided on a side surface of the housing so as to cover the gas exhaust portion; Equipped with a first opening that opens upward is formed between an upper edge portion of the cover member and an upper region of the side surface of the housing that extends above the gas exhaust portion; the gas discharge unit includes a valve body configured to move outward relative to a side surface of the housing to discharge the gas; a wall portion of the cover member that is spaced apart from the gas exhaust portion and faces at least the gas exhaust portion among the side surfaces of the housing includes a third opening; A cover structure in which at least a portion of the third opening is disposed inside an outer peripheral edge portion of the valve body when viewed in an axial direction parallel to the movement direction of the valve body.

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