Battery unit

Abstract

To improve strength against an impact from above a battery unit.SOLUTION: A battery unit is disposed between two side members provided at a vehicle and two cross members provided at the vehicle. The battery unit includes: a battery pack configured to supply electric power to the vehicle; a protection cover covering the battery pack at the upper side of the battery pack; and skeleton frames which are located at the lower side of the protection cover, span the two cross members, and are welded to the protection cover and fastened to the two cross members.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a battery unit for a vehicle. [Background technology]

[0002] Vehicles such as hybrid vehicles (HVs) and electric vehicles (EVs) are equipped with a battery unit that supplies electricity to the vehicle. The battery unit has a battery pack. Known examples of this type of vehicle include one in which a protective cover is provided on the battery pack (see, for example, Patent Document 1) and one in which a framework member is provided across two cross members (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-84340 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-136909 Summary of the Invention [Problem to be solved by the invention]

[0004] In the prior art, the battery pack is simply covered with a cover, which has the problem of being weak in strength against impacts from above the battery unit.

[0005] The present invention has been made in view of the above, and one of its objects is to improve the strength of a battery unit against impacts from above. [Means for solving the problem]

[0006] The battery unit of the present invention is a battery unit arranged between two side members provided on a vehicle and two cross members provided on the vehicle, and comprises a battery pack that supplies electricity to the vehicle, a protective cover that covers the battery pack above the battery pack, and a skeletal frame that is located below the protective cover, spans the two cross members, is welded to the protective cover, and is fastened to the two cross members.

[0007] With this configuration, the skeleton frame is welded to the protective cover and fastened to the two cross members, improving the strength (proof strength) of the battery unit against impacts from above.

[0008] The battery unit is, for example, arranged in a direction intersecting the vertical direction with the battery pack and includes a control device that controls the battery pack, and the protective cover has a first cover member that covers the battery pack above the battery pack and a second cover member that covers the control device above the control device, and at least one of the skeletal frames is provided on each of the first cover member and the second cover member.

[0009] With this configuration, the protective cover is divided into at least a first cover member that covers the battery pack and a second cover member that covers the control device, so that when repairing the control device, only the second cover member can be removed, thereby improving workability on the battery unit.

[0010] In the battery unit, for example, a portion of the first cover member and a portion of the second cover member overlap each other to form a labyrinth structure.

[0011] With this configuration, it is possible to prevent liquids such as water from entering the battery unit from between the first cover member and the second cover member, thereby improving the waterproofing of the battery unit. [Effects of the Invention]

[0012] The battery unit according to the present invention has the effect of improving the strength of the battery unit against impacts from above. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing the general shape of a vehicle equipped with a battery unit according to an embodiment. [Figure 2] FIG. 2 is a plan view showing a floor and a battery unit of a vehicle according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view showing the labyrinth structure of the protective cover of the battery unit according to the embodiment. [Figure 5] FIG. 5 is a plan view showing the battery unit according to the embodiment, with a protective cover partially removed. [Figure 6] FIG. 6 is a cross-sectional view showing a portion including a protruding portion of a skeleton frame in a battery unit according to an embodiment. [Figure 7] FIG. 7 is a perspective view showing a portion including a blower in the battery unit according to the embodiment. [Figure 8] FIG. 8 is a plan view showing a portion including a blower in the battery unit according to the embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing a mounting structure of a blower in a battery unit according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] One embodiment will be described below. Note that the drawings are schematic, and the dimensional relationships and ratios of elements may differ from reality. Furthermore, the drawings may include portions with different dimensional relationships and ratios. Furthermore, in this specification, ordinal numbers are used only to distinguish between parts, members, portions, positions, directions, etc., and do not indicate order or priority.

[0015] FIG. 1 is a diagram showing the general shape of a vehicle 100 equipped with a battery unit 1 according to an embodiment. The vehicle is an electric vehicle such as a hybrid vehicle or an electric vehicle. The vehicle 100 has a front seat 103, a rear seat 104, and a battery unit 1 on a floor 102 of an interior 101. The battery unit 1 is installed under the front seat 103. The battery unit 1 is also referred to as a power supply unit.

[0016] Each drawing shows a three-dimensional coordinate system. In the three-dimensional coordinate system, the fore-and-aft direction of the vehicle 100 and the battery unit 1 is the X-axis direction, the width direction (left-right direction) is the Y-axis direction, and the up-and-down direction (height direction) is the Z-axis direction. The positive direction of the X-axis is the rear in the fore-and-aft direction, and the negative direction of the X-axis is the front in the fore-and-aft direction. The positive direction of the Y-axis is the right, and the negative direction of the Y-axis is the left. The positive direction of the axis is upward, and the negative direction of the Z-axis is downward. Furthermore, hereinafter, unless otherwise specified, the fore-and-aft direction is the fore-and-aft direction of the vehicle 100 and the battery unit 1, the width direction is the width direction of the vehicle 100 and the battery unit 1, and the up-and-down direction is the up-and-down direction of the vehicle 100 and the battery unit 1.

[0017] Fig. 2 is a plan view showing the floor 102 and battery unit 1 of the vehicle 100 according to the embodiment. As shown in Fig. 2, the floor 102 is part of the vehicle body and includes at least a left side member 5L, a right side member 5R, a front cross member 6F, and a rear cross member 6R. The floor 102 is also referred to as a floor panel.

[0018] The left side member 5L and the right side member 5R each extend in the front-to-rear direction and are arranged at a distance from each other in the width direction. The front cross member 6F and the rear cross member 6R each extend in the width direction and are arranged at a distance from each other in the front-to-rear direction. The front cross member 6F and the rear cross member 6R are provided across the left side member 5L and the right side member 5R, respectively. A plate-shaped panel portion is provided in the area of ​​the floor 102 surrounded by the left side member 5L, right side member 5R, front cross member 6F, and rear cross member 6R, and the battery unit 1 is disposed above this panel portion.

[0019] Figure 3 is a cross-sectional view taken along line III-III in Figure 2. As shown in Figures 2 and 3, the battery unit 1 includes a case 11, a battery pack 12, a blower 13 (Figure 2), a control device 14 (Figure 2), and a waterproof tray 15 (Figure 3). The case 11 houses the battery pack 12, the blower 13, and the control device 14. The battery pack 12, the blower 13, and the control device 14 are aligned in the width direction. The blower 13 is disposed on one side (for example, the right side) of the battery pack 12, and the control device 14 is disposed on the other side (for example, the left side) of the battery pack 12. The waterproof tray 15 houses the case 11, the battery pack 12, the blower 13, and the control device 14. The blower 13 is an example of an electrical component.

[0020] The battery pack 12 is a secondary battery (battery) that supplies electricity to the motor of the vehicle 100, and is, for example, a lithium-ion battery. The battery pack 12 is charged by regenerative power or power from a charger. The blower 3 blows air onto the battery pack 12 inside the protective cover 2 to cool the battery pack 12. The control device 14 controls the battery pack 12 and the blower 13. The control device 14 is, for example, a battery management system, and has multiple electronic components. The multiple electronic components include high-voltage components to which a high voltage is applied.

[0021] Each part will be explained in detail below.

[0022] 3, the waterproof tray 15 is open upward. The waterproof tray 15 is fastened to the front cross member 6F and the rear cross member 6R via a plurality of brackets 32, for example, by bolts 27 and 28. The brackets 32 are also referred to as waterproof tray brackets.

[0023] As shown in FIGS. 2 and 3, the case 11 has a lower case 21 (FIG. 3) and a protective cover 22.

[0024] The lower case 21 is open upward and houses the battery pack 12, blower 13, and control device 14 inside. The lower case 21 is fixed to the floor 102. For example, the lower case 21 is fastened to the front cross member 6F and the rear cross member 6R via brackets 32. As a result, the battery pack 12 is fastened to the front cross member 6F and the rear cross member 6R via the lower case 21 and brackets 32. In other words, the brackets 32 fasten the battery pack 12 (lower case 21) and the waterproof tray 15 to the front cross member 6F and the rear cross member 6R.

[0025] The protective cover 22 is provided above the lower case 21 and covers the opening of the lower case 21. The protective cover 22 is provided above the battery pack 12, the blower 13, and the control device 14 and covers the battery pack 12, the blower 13, and the control device 14.

[0026] The protective cover 22 is made up of a combination of multiple members. For example, as shown in Fig. 2, the protective cover 22 has a first cover member 23, a second cover member 24, and a third cover member 25. The protective cover 22 is fixed to the front cross member 6F and the rear cross member 6R by bolts 27 to 29, etc.

[0027] The first cover member 23 is positioned at least above the battery pack 12 and covers the battery pack 12. The second cover member 24 is positioned at least above the control device 14 and covers the control device 14. The third cover member 25 is positioned at least above the blower 13 and covers the blower 13.

[0028] 4 is a cross-sectional view showing the labyrinth structure 22a in the protective cover 22 of the battery unit 1 according to the embodiment. As shown in FIGS. 2 and 3, the first cover member 23 and the second cover member 24 are overlapped in the vertical direction at overlapping portions 23a, 24a, which are parts of each other. As an example, the overlapping portion 24a of the second cover member 24 is overlapped above the overlapping portion 23a of the first cover member 23 with a gap therebetween. Note that the overlapping portion 24a of the second cover member 24 may be overlapped below the overlapping portion 23a of the first cover member 23 with a gap therebetween. Furthermore, the overlapping portion 23a of the first cover member 23 and the overlapping portion 24a of the second cover member 24 may be in contact with each other.

[0029] As shown in FIG. 4, the two overlapping portions 23a, 24a form a labyrinth structure 22a. Specifically, the overlapping portion 23a of the first cover member 23 has a first portion 23aa, a second portion 23ab, and a third portion 23ac. The first portion 23aa extends in a direction perpendicular to the up-down direction. The second portion 23ab extends upward and leftward from the left end of the first portion 23aa (the negative direction of the Y-axis). In other words, the second portion 23ab extends diagonally upward and leftward from the first portion 23aa. The second portion 23ab is also referred to as an inclined portion. The third portion 23ac extends leftward from the left end of the second portion 23ab (the negative direction of the Y-axis).

[0030] The overlapping portion 24a of the second cover member 24 has a first portion 24aa, a second portion 24ab, and a third portion 24ac. The first portion 24aa extends in a direction perpendicular to the up-down direction. The second portion 24ab extends downward as it moves rightward from the right end (positive direction of the Y axis) of the first portion 24aa. In other words, the second portion 24ab extends diagonally downward to the right from the first portion 24aa. The second portion 24ab is also referred to as an inclined portion. The third portion 24ac extends rightward from the right end (positive direction of the Y axis) of the second portion 24ab.

[0031] A third portion 24ac of the overlapping portion 24a of the second cover member 24 is located above, and spaced from, a first portion 23aa of the overlapping portion 23a of the first cover member 23. A second portion 24ab of the overlapping portion 24a of the second cover member 24 is located above, and spaced from, a second portion 24ab of the overlapping portion 24a of the second cover member 24. A first portion 24aa of the overlapping portion 24a of the second cover member 24 is located above, and spaced from, a third portion 23ac of the overlapping portion 23a of the first cover member 23.

[0032] The labyrinth structure 22a configured as described above prevents liquids such as water from entering the inside of the protective cover 22 from between the overlapping portion 23a of the first cover member 23 and the overlapping portion 24a of the second cover member 24. The gap between the overlapping portion 23a of the first cover member 23 and the overlapping portion 24a of the second cover member 24 may be sealed with a sealing member.

[0033] 2, a plurality of (for example, two) skeletal frames 26A, 26B are fixed to the protective cover 22. The skeletal frame 26A is fixed to the first cover member 23, and the skeletal frame 26B is fixed to the second cover member 24. Hereinafter, the skeletal frame 26 will be used as a general term for the plurality of skeletal frames 26A, 26B. Although the following describes an example in which one skeletal frame 26 is provided for each of the first cover member 23 and the second cover member 24, the number of skeletal frames 26 is not limited to this. For example, a plurality of skeletal frames 26 may be provided for each of the first cover member 23 and the second cover member 24.

[0034] Fig. 5 is a plan view showing the battery unit 1 according to the embodiment, with part of the protective cover 22 removed. Specifically, Fig. 5 shows the battery unit 1 with the first cover member 23 and the second cover member 24 of the protective cover 22 removed.

[0035] 5, the multiple skeletal frames 26 each extend in the front-to-rear direction and are arranged at intervals in the width direction. Each skeletal frame 26 is provided across the front cross member 6F and the rear cross member 6R and fixed to the front cross member 6F and the rear cross member 6R. In other words, each skeletal frame 26 bridges the front cross member 6F and the rear cross member 6R.

[0036] The skeleton frame 26 is a plate member whose longitudinal direction is the front-to-rear direction. The skeleton frame 26 is made, for example, by processing a hat-shaped member, and at least a portion of the cross section has a hat-shaped cross section. The skeleton frame 26 is made, for example, from a metal material.

[0037] The skeletal frame 26 has a front end 26a, a rear end 26b opposite the front end 26a, a left end 26c, and a right end 26d opposite the left end 26c.

[0038] As shown in FIGS. 2 and 3, the front end 26a and rear end 26b of the skeletal frame 26 are fastened to the front cross member 6F and the rear cross member 6R by bolts 27. The bolts 27 are coupled with nuts (not shown) to secure the skeletal frame 26 to the front cross member 6F and the rear cross member 6R. More specifically, as shown in FIG. 3, the front end 26a and rear end 26b of the skeletal frame 26 overlap brackets 32 and are fastened together with the brackets 32 to the front cross member 6F and the rear cross member 6R by bolts 27. That is, the skeletal frame 26 is fastened together with the brackets 32 to the front cross member 6F and the rear cross member 6R. Here, the brackets 32 that secure the skeletal frame 26B to the front cross member 6F and the rear cross member 6R are fastened to the front cross member 6F and the rear cross member 6R by bolts 28 (FIG. 2) in addition to the bolts 27. However, the bolts 28 do not fasten the skeletal frame 26B to the front cross member 6F and the rear cross member 6R. In other words, the bolts 28 fasten the waterproof tray 15 to the front cross member 6F and the rear cross member 6R via the brackets 32, but do not fasten the skeletal frame 26B. Therefore, when performing maintenance on the control device 14, the bolts 27 can be removed and only the second cover member 24 can be removed. At this time, because the bolts 28 fasten the waterproof tray 15 to the front cross member 6F and the rear cross member 6R, there is no risk of the waterproof tray 15 (battery pack 12) coming off the front cross member 6F and the rear cross member 6R.

[0039] As shown in FIG. 5 , the left end 26c and the right end 26d of the skeletal frame 26 have concave-convex portions 26e. The concave-convex portions 26e have a plurality of convex portions 26ea arranged at intervals in the front-rear direction. Each convex portion 26ea is fixed to the protective cover 22. Specifically, each convex portion 26ea is welded to the protective cover 22. More specifically, the convex portion 26ea of ​​the skeletal frame 26A is welded to the first cover member 23, and the convex portion 26ea of ​​the skeletal frame 26B is welded to the second cover member 24. The welding between the skeletal frame 26 and the protective cover 22 is, for example, spot welding, but is not limited to this. In FIG. 5 , welded points 26g on the skeletal frame 26 are indicated by black circles. Note that the welded points 26g between the skeletal frame 26 and the protective cover 22 are not limited to the above.

[0040] FIG. 6 is a cross-sectional view showing a portion including a protrusion 26i of a skeletal frame 26A in a battery unit 1 according to an embodiment. As shown in FIGS. 5 and 6, the skeletal frame 26A is provided with a protrusion 26i. A plurality of (for example, two) protrusions 26i are provided on a left end portion 26c of the skeletal frame 26A. The plurality of protrusions 26i are provided at intervals in the front-rear direction. The plurality of protrusions 26i protrude leftward from the left end portion 26c, i.e., toward the opposite side from the blower 13. The protrusions 26i are integrally formed with the skeletal frame 26A. Note that the protrusions 26i may be provided as separate members from the skeletal frame 26A and fixed to the skeletal frame 26A by fastening or the like.

[0041] As shown in FIG. 6, the protrusion 26i is located on the upper side of the battery pack 12. The protrusion 26i has a first portion 26ia, a second portion 26ib, and a third portion 26ic. The first portion 26ia extends in a direction perpendicular to the up-down direction. The second portion 26ib extends downward and leftward from the left end (negative direction of the Y axis) of the first portion 26iaa. In other words, the second portion 26ib extends diagonally downward and leftward from the first portion 26ia. The second portion 26ib is also referred to as an inclined portion. The third portion 26ic extends leftward from the left end (negative direction of the Y axis) of the second portion 26ib.

[0042] When the battery pack 12 moves upward toward the skeletal frame 26A for some reason, the upper part of the battery pack 12 comes into contact with the third portion 26ic of the protrusion 26i configured as described above. In this state, the protrusion 26i restricts the upward movement of the battery pack 12.

[0043] As shown in FIG. 5, the skeletal frame 26A is provided with a fixing portion 26h. The blower 13 is fixed to the fixing portion 26h. In other words, the blower 13 is attached to the fixing portion 26h. The fixing portion 26h is also referred to as a blower attachment portion. A plurality of fixing portions 26h (for example, two) are provided at the right end portion 26d of the skeletal frame 26A. The fixing portions 26h are provided at intervals in the front-rear direction. The fixing portions 26h protrude rightward from the left end portion 26c, i.e., toward the opposite side from the battery pack 12. The fixing portions 26h are integrally formed with the skeletal frame 26A. Note that the fixing portions 26h may be provided as separate members from the skeletal frame 26A and fixed to the skeletal frame 26A by fastening or the like. The shape of the fixing portions 26h will be described in detail later.

[0044] 3, the battery pack 12 has a plurality of battery cells 31 and a bracket 32. The plurality of battery cells 31 stores electric power to be supplied to the motor of the vehicle 100. The bracket 32 ​​supports the plurality of battery cells 31. The bracket 32, together with the skeleton frame 26, is fastened to the front cross member 6F and the rear cross member 6R by bolts 27.

[0045] Fig. 7 is a perspective view showing a portion of the battery unit 1 according to the embodiment that includes the blower 13. Fig. 8 is a plan view showing a portion of the battery unit 1 according to the embodiment that includes the blower 13.

[0046] 7 and 8, the blower 13 has a case 41. The case 41 houses an impeller and a motor that rotates the impeller. The blower 13 rotates the impeller with the motor, thereby drawing in air from an air intake port of the case 41 and blowing the drawn-in air from an air outlet of the case 41 toward the battery pack 12, thereby cooling the battery pack 12 with the air flow. In other words, the blower 13 generates an air flow that cools the battery pack 12.

[0047] The case 41 has a case body 41a that houses the impeller and the motor, and a plurality of fixing portions 41b and 41c that protrude from the case body 41a.

[0048] Next, we will explain the fixing structure of blower 13. Blower 13 is fixed to skeleton frame 26A and lower case 21. In detail, fixing portion 41b of case 41 is fastened to fixing portion 26h of skeleton frame 26A with bolts 42, and fixing portion 41c is fastened to fixing portion 21b of lower case 21 with bolts 42.

[0049] Fig. 9 is a cross-sectional view showing the mounting structure of the blower 13 in the battery unit 1 according to the embodiment. As shown in Fig. 9, the fixing portion 41b is placed on top of the fixing portion 21h of the skeletal frame 26A and fastened to the fixing portion 21h of the skeletal frame 26A with a bolt 42. The bolt 42 is coupled with a nut 43 to fix the fixing portion 41b of the blower 13 to the fixing portion 26h of the skeletal frame 26A.

[0050] Here, the fixing portion 26h of the skeletal frame 26A has a first portion 26ha, a second portion 26hb, and a third portion 26hc. The first portion 26ha extends in a direction perpendicular to the up-down direction. The second portion 26hb extends downward as it moves rightward from the right end (positive direction of the Y axis) of the first portion 26aa. In other words, the second portion 26hb extends diagonally downward to the right from the first portion 26aa. The second portion 26hb is also referred to as an inclined portion. The third portion 26hc extends rightward from the right end (positive direction of the Y axis) of the second portion 26hab. The fixing portion 41b of the blower 13 is fastened to this third portion 26hc.

[0051] 8, fixing portion 21b of lower case 21 protrudes from the inner surface of lower case 21. Fixed portion 21b is provided with a female thread. Fixed portion 41c of case 41 is placed on top of fixed portion 21b of lower case 21 and fastened to fixed portion 21b with bolt 42. Bolt 42 engages with the female thread and fixes fixed portion 41c of blower 13 to fixed portion 21b of lower case 21.

[0052] In other words, blower 13 having the above-described configuration is fixed such that at least a portion of case body 41a is suspended from skeletal frame 26A and lower case 21 via fixing portions 41b and 41c.

[0053] As described above, the battery unit 1 of this embodiment is disposed between the right side member 5R and the left side member 5L (two side members) provided on the vehicle 100 and the front cross member 6F and the rear cross member 6R (two cross members) provided on the vehicle 100. The battery unit 1 includes a battery pack 12, a protective cover 22, and a skeletal frame 26. The battery pack 12 supplies electricity to the vehicle 100. The protective cover 22 covers the battery pack 12 from above. The skeletal frame 26 is located below the protective cover 22 and extends across the front cross member 6F and the rear cross member 6R. It is welded to the protective cover 22 and fastened to the front cross member 6F and the rear cross member 6R.

[0054] With this configuration, the skeletal frame 26 is welded to the protective cover 22 and fastened to the front cross member 6F and the rear cross member 6R, improving the strength (resistance) of the battery unit 1 against impacts from above. Therefore, even if an object inside the vehicle compartment falls onto the battery unit 1, it is possible to prevent the battery pack 12 and the control device 14 (high-voltage components, etc.) inside the battery unit 1 from receiving an impact. Furthermore, in the event of a longitudinal collision of the vehicle 100, the skeletal frame 26 can prevent the gap between the front cross member 6F and the rear cross member 6R on the floor 102 from being crushed and narrowed. Therefore, with the above configuration, the safety of the battery unit 1 can be improved.

[0055] The battery unit 1 also includes a control device 14 that is arranged, for example, with the battery pack 12 in a direction intersecting the vertical direction and that controls the battery pack 12. The protective cover 22 has a first cover member 23 that covers the battery pack 12 from above the battery pack 12, and a second cover member 24 that covers the control device 14 from above the battery pack 12. At least one skeletal frame 26 is provided on each of the first cover member 23 and the second cover member 24.

[0056] With this configuration, the protective cover 22 is divided into at least a first cover member 23 that covers the battery pack 12 and a second cover member 24 that covers the control device 14, so that when repairing the control device 14, only the second cover member 24 can be removed, thereby improving the ease of working on the battery unit 1.

[0057] In the battery unit 1, for example, the overlapping portion 23a (part) of the first cover member 23 and the overlapping portion 24a (part) of the second cover member 24 overlap each other to form the labyrinth structure 22a.

[0058] With this configuration, it is possible to prevent liquids such as water from entering the battery unit 1 between the first cover member 23 and the second cover member 24, thereby improving the waterproofness of the battery unit 1.

[0059] Although the embodiments of the present invention have been described, the above embodiments are presented as examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. The above embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions described in the claims and their equivalents. [Explanation of symbols]

[0060] 1...Battery unit, 5L...Left side member (side member), 5R...Right side member (side member), 6F...Front cross member (cross member), 6R...Rear cross member (cross member), 12...Battery pack, 13...Blower (Electrical parts) , 14...control device, 21...lower case, 22...protective cover, 22a...labyrinth structure, 23...first cover member, 23a...overlapping portion (part), 24...second cover member, 24a...overlapping portion (part), 26, 26A, 26B...skeletal frame, 26c...left end portion (other end portion), 26d...right end portion (one end portion), 26h...Fixed part, 26i...protrusion, 100...vehicle.

Claims

1. A battery unit disposed between two side members provided on a vehicle and two cross members provided on the vehicle, a battery pack that supplies electricity to the vehicle; Blower and a lower case that opens upward and accommodates the battery pack and the blower therein; a protective cover provided above the lower case to cover the opening of the lower case and above the battery pack; a plurality of skeletal frames located below the protective cover, spanning the two cross members, welded to the protective cover, and fastened to the two cross members; Equipped with The blower is disposed below the skeleton frame, At least one of the plurality of skeletal frames is provided with a plurality of fixing portions extending toward the blower, The battery unit has the plurality of fixing portions fixed to an upper portion of the blower, and a lower portion of the blower fixed to the lower case.

2. a control device arranged in a direction intersecting the vertical direction with the battery pack and controlling the battery pack; The protective cover is a first cover member that covers the battery pack from above; a second cover member that covers the control device from above the control device; and At least one skeletal frame is provided on each of the first cover member and the second cover member. The battery unit according to claim 1 .

3. A portion of the first cover member and a portion of the second cover member overlap each other to form a labyrinth structure. The battery unit according to claim 2 .

Images