阅读说明：本技术 蓄电池包的配置结构 (Configuration structure of storage battery pack ) 是由 大熊香苗 克里斯多弗·郎 于 2019-07-04 设计创作，主要内容包括：在蓄电池包的配置结构中,蓄电池壳体(20)的壳体主体(31)为金属压铸制,因此,通过使从壳体底壁(31a)向上方隆起并沿车宽方向延伸的横梁(31e)和从壳体侧壁(31d)向车宽方向外侧突出的第二固定部(31g)与壳体主体(31)一体地形成能够削减部件数量、重量,不仅如此,而且能够使具备横梁(31e)及第二固定部(31g)的壳体主体(31)的强度增加来提高耐侧面碰撞性能。另外,从壳体侧壁(31d)向车宽方向外侧突出的第二固定部(31g)固定于地板框架(15),因此,侧面碰撞的碰撞载荷从地板框架(15)向壳体主体(31)的横梁(31e)直接地传递并被支承,由此,即使通过使地板框架(15)的强度下降来实现轻量化,也能够确保耐侧面碰撞性能。(In the arrangement structure of the battery pack, a housing main body (31) of a battery housing (20) is made of metal by die casting, so that the number of components and the weight can be reduced by integrally forming a cross beam (31e) rising upward from a housing bottom wall (31a) and extending in the vehicle width direction and a second fixing portion (31g) protruding outward from a housing side wall (31d) in the vehicle width direction with the housing main body (31), and the strength of the housing main body (31) provided with the cross beam (31e) and the second fixing portion (31g) can be increased to improve the side collision resistance. Further, since the second fixing portion (31g) protruding outward in the vehicle width direction from the case side wall (31d) is fixed to the floor frame (15), the collision load of a side collision is directly transmitted from the floor frame (15) to the cross member (31e) of the case body (31) and supported, and therefore, even if the strength of the floor frame (15) is reduced to achieve weight reduction, the side collision resistance can be ensured.)

1. A battery pack placement structure in which a battery pack (21) is placed at a lower portion of a vehicle body, and the battery pack (21) houses a drive battery (34) for an electric vehicle inside a case body (31) and a cover (32), the battery pack placement structure being characterized in that,

the vehicle body is provided with: left and right floor frames (15) extending in the front-rear direction; and a first floor cross member (16) on the front side and a second floor cross member (17) on the rear side, which connect the left and right floor frames (15) in the vehicle width direction,

the case body (31) is made of metal by die casting, and is integrally formed with a cross member (31e) that rises upward from a case bottom wall (31a) and extends in the vehicle width direction, a first fixing portion (31f) provided on the cross member (31e) is fixed to the second floor cross member (17), and a second fixing portion (31g) that protrudes outward in the vehicle width direction from a case side wall (31d) is fixed to the floor frame (15),

the cover (32) is formed with a recess (32a) that is recessed toward the cross member (31e), and the recess (32a) and the second floor cross member (17) at least partially overlap when viewed in the vertical direction.

2. The battery pack arrangement structure according to claim 1,

protrusions (32d, 32e) that cover electrical components (35) disposed above the drive battery (34) protrude upward from the cover (32), and the protrusions (32d, 32e) are disposed between the first floor cross member (16) and the second floor cross member (17).

3. The battery pack arrangement structure according to claim 1 or 2,

the case rear wall (31c) is located forward of the front end of the fuel tank (23) or the front end of the rear subframe.

Technical Field

The present invention relates to a battery pack placement structure in which a battery pack is placed in a lower portion of a vehicle body, and the battery pack accommodates a drive battery of an electric vehicle in a case body and a cover.

Background

A battery case that houses a drive battery of an electric vehicle is provided with a recess that extends in a vehicle width direction and is recessed downward, and a floor cross member of a vehicle body is fitted into the recess from above, so that the battery case is disposed at a high position while avoiding interference with the floor cross member, and a minimum ground height is secured, and this proposal is widely known from patent document 1 below.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2017-226353

Disclosure of Invention

Problems to be solved by the invention

In the above-described conventional technique, the battery case is made of a steel plate that is over-press-formed, and the vertical frame that is fixed along the side wall of the battery case is fastened and coupled to the rocker of the vehicle body by bolts, and therefore, if the side impact resistance of the battery case is to be improved, it is necessary to reinforce the battery case with a reinforcing member or provide an impact absorbing portion inside the rocker, which causes a problem of an increase in the number of components and an increase in weight.

The present invention has been made in view of the above circumstances, and an object thereof is to improve the side impact resistance of a battery pack while avoiding an increase in the number of components and weight.

Means for solving the problems

In order to achieve the above object, according to the present invention, there is provided a battery pack placement structure for placing a battery pack in a lower portion of a vehicle body, the battery pack accommodating a drive battery of an electric vehicle in a case body and a cover, the vehicle body including: left and right floor frames (floor frames) extending in the front-rear direction; and a first floor cross member on the front side and a second floor cross member on the rear side, which connect the left and right floor frames in the vehicle width direction, wherein the housing body is made of metal die casting, and a cross member which is raised upward from a housing bottom wall and extends in the vehicle width direction is integrally formed, a first fixing portion provided on the cross member is fixed to the second floor cross member, a second fixing portion which protrudes outward in the vehicle width direction from a housing side wall is fixed to the floor frame, the cover is formed with a recessed portion which is recessed toward the cross member, and the recessed portion and the second floor cross member at least partially overlap each other when viewed in the vertical direction.

Further, according to a second aspect of the present invention, in addition to the first aspect, a raised portion that covers an electric component disposed above the driving battery protrudes upward from the cover, and the raised portion is disposed between the first floor cross member and the second floor cross member.

Further, according to a third aspect of the present invention, in addition to the first or second aspect, the battery pack placement structure is characterized in that the case rear wall is located forward of the front end portion of the fuel tank or the front end portion of the rear subframe.

The battery module 34 of the embodiment corresponds to a driving battery of the present invention.

Effects of the invention

According to the first aspect of the present invention, the battery pack, in which the drive battery for the electric vehicle is housed inside the case body and the cover, is disposed at the lower portion of the vehicle body.

Since the case body is made of metal by die casting, the number of components and the weight can be reduced by forming the cross member rising upward from the bottom wall of the case and extending in the vehicle width direction and the second fixing portion protruding outward from the side wall of the case in the vehicle width direction integrally with the case body, and the strength of the case body including the cross member and the second fixing portion can be increased to improve the side collision resistance.

Further, since the second fixing portion protruding outward in the vehicle width direction from the side wall of the housing is fixed to the floor frame, the collision load of the side collision is directly transmitted from the floor frame to the cross member of the housing body and is supported, whereby the side collision resistance can be ensured even if the floor frame is reduced in strength to achieve weight reduction, and the cover is formed with the recessed portion recessed toward the cross member, and the recessed portion and the second floor cross member at least partially overlap when viewed in the vertical direction, so that the battery pack can be arranged at a high position while avoiding interference with the second floor cross member, and the lowest ground height of the vehicle can be ensured.

Further, according to the second aspect of the present invention, since the raised portion that covers the electric component disposed above the driving battery protrudes upward from the cover, and the raised portion is disposed between the first floor cross member and the second floor cross member, it is possible to mount the battery pack having the raised portion on the vehicle body while avoiding interference with the first and second floor cross members.

Further, according to the third aspect of the present invention, since the case rear wall is located forward of the front end portion of the fuel tank or the front end portion of the rear subframe, the battery pack can be prevented from projecting rearward, and the seating performance of the rear seat can be ensured.

Drawings

Fig. 1 is a vehicle body side view of a plug-in hybrid vehicle. (first embodiment)

Fig. 2 is a view in the direction 2 of fig. 1. (first embodiment)

Fig. 3 is a sectional view taken along line 3-3 of fig. 2. (first embodiment)

Fig. 4 is a 4-4 line-up view of fig. 3. (first embodiment)

Fig. 5 is an exploded perspective view of the battery pack. (first embodiment)

Fig. 6 is a perspective view showing an attached state of the battery pack. (first embodiment)

Fig. 7 is a view from the direction of 7 in fig. 6. (first embodiment)

Description of the reference numerals

15 floor frame

16 first floor beam

17 second floor beam

21 accumulator bag

23 Fuel tank

31 main body of the shell

31a bottom wall of the case

31c rear wall of housing

31d side wall of the housing

31e Cross Member

31f first fixing part

31g second fixing part

32 cover

32a recess

32d bump

32e bump

34 accumulator module (drive accumulator)

35 electrical components.

Detailed Description

Embodiments of the present invention will be described below with reference to fig. 1 to 7. In the present specification, the front-rear direction, the left-right direction (vehicle width direction), and the up-down direction are defined with reference to an occupant seated in a driver's seat.

First embodiment

As shown in fig. 1, 2, and 4, a front-wheel-drive plug-in hybrid vehicle is mounted on a vehicle body front portion: an electric motor 11 that drives the front wheels; an engine 12 for driving a generator that charges a battery; and a power drive unit 13 including an inverter for controlling driving of the electric motor 11.

A pair of left and right rocker beams 14 extending in the front-rear direction are disposed on the left and right side portions of the vehicle body center, a pair of left and right floor frames 15 extending in the front-rear direction are disposed on the vehicle width direction inner sides of the left and right rocker beams 14, a first floor cross member 16 extending in the vehicle width direction connects between the left and right rocker beams 14 and the front portions of the left and right floor frames 15, and a second floor cross member 17 extending in the vehicle width direction connects between the left and right rocker beams 14 and the front-rear direction intermediate portions of the left and right floor frames 15. The first floor cross member 16 and the second floor cross member 17 are connected by a plurality of seat rails 18 extending in the front-rear direction, and the front seats 19 are supported by these seat rails 18.

A battery pack 21 that houses a battery that drives the electric motor 11 in a battery case 20 is supported by the lower surfaces of the left and right floor frames 15 and the second floor beam 17. A charger 22 (or a contactless charging pad) is disposed on the front side of the battery pack 21, the charger 22 is connected to an external power supply via a charging cable to charge the battery, a fuel tank 23 is disposed on the rear side of the battery pack 21, and the fuel tank 23 stores fuel for driving the engine 12.

As shown in fig. 2 to 7, the battery case 20 is configured by coupling a case main body 31 made of metal (aluminum) die-cast which is open upward and a cover 32 made of metal (aluminum) die-cast which is open downward at outer peripheral portions thereof in the vertical direction by a plurality of bolts 33. Eight battery modules 34 are mounted on the bottom of the case body 31, and electrical components 35 such as a battery control device, a terminal block, and a cell voltage sensor are disposed on the top of the eight battery modules 34.

The shallow container-shaped case body 31 includes: a substantially flat case bottom wall 31 a; a case front wall 31b, a case rear wall 31c, and left and right case side walls 31d rising from the outer periphery of the case bottom wall 31 a; and a cross member 31e connecting the left and right case side walls 31d in the vehicle width direction. The cross member 31e of the present embodiment is an assembly of a plurality of ribs rising from the case bottom wall 31a (see fig. 5), but the structure of the cross member 31e is arbitrary. A pair of left and right cylindrical first fixing portions 31f are formed on the cross member 31e of the housing body 31, and a pair of front and rear cylindrical second fixing portions 31g are formed on the outer surfaces of the left and right housing side walls 31d in the vehicle width direction. The pair of front and rear second fixing portions 31g are connected by a connecting wall 31h having an L-shaped cross section extending parallel to the case side wall 31 d. As a result, a space that is open downward is formed so as to be surrounded by the case side wall 31d, the pair of second fixing portions 31g, and the connecting wall 31h, and a plurality of ribs 31i that connect the case side wall 31d and the connecting wall 31h are formed in the space.

The lid 32 of the battery case 20 has a groove-like recess 32a recessed downward at a position corresponding to the cross member 31e of the case body 31, a pair of bolt holes 32b overlapping the pair of first fixing portions 31f of the case body 31 are formed in the recess 32a, and a pair of bolt holes 32c overlapping the pair of second fixing portions 31g of the case body 31 are formed in the right and left vehicle width direction outer walls of the lid 32. Raised portions 32d and 32e for accommodating the electric component 35 are provided in the front portion of the cover 32 so as to project upward.

The second floor cross member 17 fixed to the lower surface of the vehicle body floor 36 overlaps the cross member 31e of the housing main body 31 and the recess 32a of the cover 32 when viewed in the vertical direction (see fig. 3).

In the battery case 20 configured as described above, the two bolts 37 penetrating the two left and right first fixing portions 31f of the case body 31 and the two left and right bolt holes 32b of the cover 32 from below to above are screwed into the two nuts 38 provided on the upper surface of the first floor cross member 16, and the two bolts 39 penetrating the two left and right second fixing portions 31g of the case body 31 and the two left and right bolt holes 32c of the cover 32 from below to above are screwed into the two nuts 40 provided on the upper surface of the left and right floor frames 15, whereby the battery case 20 is fixed to the lower surface of the vehicle body floor 36.

Next, the operation of the embodiment of the present invention having the above-described configuration will be described.

Since the battery case 20 including the case body 31 and the cover 32 is made of metal, the first fixing portion 31f and the second fixing portion 31g are formed integrally with the case body 31, whereby the number of components and the weight can be reduced, and the cross member 31e is formed integrally with the case body 31, whereby the increase in the number of components and the weight can be minimized, the strength of the case body 31 can be increased, and the side collision resistance can be improved.

That is, since the two front and rear second fixing portions 31g and the connecting wall 31h that is formed in a surface shape facing the case side wall 31d and connects the two second fixing portions 31g in the front-rear direction are integrally formed in the case side wall 31d of the case body 31 of the battery case 20 facing the floor frame 15, when a collision load is input from the floor frame 15 to the case body 31 of the battery case 20 due to a side collision of the vehicle, the space surrounded by the two second fixing portions 31g, the connecting wall 31h, and the case side wall 31d is crushed, and collision energy is effectively absorbed.

At this time, since the vehicle-width-direction outer end of the second fixing portion 31g is positioned inward in the vehicle width direction from the vehicle-width-direction outer end of the floor frame 15, the collision load of the side collision can be supported preferentially by the floor frame 15, and the collision load that is not completely received can be received by the battery case 20, whereby damage to the battery case 20 can be minimized.

Further, since the second fixing portion 31g and the connecting wall 31h are formed integrally with the metal die-cast case body 31, the rigidity of the case body 31 can be improved by the second fixing portion 31g and the connecting wall 31h, while the number of components can be reduced. Further, since the case body 31 includes the rib 31i between the two second fixing portions 31g and the rib 31i connects the case side wall 31d and the connecting wall 31h in the vehicle width direction, the second fixing portions 31g and the connecting wall 31h can be reinforced by the rib 31i to further improve the side collision resistance.

Further, since the second fixing portion 31g protruding outward in the vehicle width direction from the case side wall 31d of the case body 31 is fixed to the floor frame 15 by the bolt 39 and the nut 40, the collision load of the side collision is directly transmitted from the floor frame 15 to the cross member 31e of the case body 31 and is supported, and therefore, even if the strength of the floor frame 15 is reduced to achieve weight reduction, the side collision resistance can be ensured, and further, the cover 32 of the battery case 20 is formed with the concave portion 32a recessed downward toward the cross member 31e of the case body 31, and the concave portion 32a overlaps with the second floor cross member 17 of the vehicle body when viewed in the vertical direction, so that the battery case 20 can be disposed at a high position while avoiding interference with the second floor cross member 17, and the lowest ground height of the vehicle can be ensured.

Further, the raised portions 32d, 32e that house the electrical components 35 such as the battery control device, the terminal block, and the cell voltage sensor are formed on the upper surface of the cover 32 of the battery case 20, but since the raised portions 32d, 32e are disposed between the first floor cross member 16 and the second floor cross member 17 when viewed in the vertical direction, the battery case 20 having the raised portions 32d, 32e can be mounted on the vehicle body while avoiding interference with the first floor cross member 16 and the second floor cross member 17.

Further, since the case rear wall 31c of the battery case 20 is located forward of the front end portion of the fuel tank 23, the battery case 20 can be prevented from projecting rearward, and the seating performance of the rear seat can be ensured.

While the embodiments of the present invention have been described above, the present invention may be variously modified in design without departing from the gist thereof.

For example, the rear subframe may be disposed at the position of the fuel tank 23, and the case rear wall 31c of the case main body 31 may be positioned forward of the front end portion of the rear subframe.

In the embodiment, both the case body 31 and the lid 32 of the battery case 20 are formed by metal die casting, but the lid 32 is not necessarily formed by metal die casting.