JP2012106558A - Support structure for battery unit for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely separate a tray loaded with a battery from a vehicle body only in the case of collision.SOLUTION: A fitting bracket 14 provided in a cross member 15 connected to a rear part of a dashboard lower panel 60 and extending in the vehicle cross direction is fastened to a front frame 31 of the tray 11, which is loaded with the battery 12, by a bolt 59 and a nut 58. Since a front wall 31a of the front frame 31 is formed with a step part 31c formed so that the fastening part is formed larger in thickness than other parts, the tray 11, in a front collision of the vehicle, is about to move forward from the vehicle body under its own inertia, and when the fitting bracket 14 is about to move upward with the dashboard lower panel 60 and the cross member 15 due to a shock in the collision, the bending moment M works to the fastening part and the stress concentrates to the step part 31c and breaks the step part 31c. With this structure, a front part of the tray 11 is separated from the cross member 15, and outbreaks of malfunction on electrical safety such as grounding to be caused by the battery 12 itself or a high-voltage distribution system near the battery 12 pushed to the vehicle body.

Description

  The present invention relates to a support structure for a vehicle battery unit in which a battery mounting member on which a battery is mounted and a mounting bracket provided on a vehicle frame are fastened by a fastening member.

  The following Patent Documents 1 to 3 disclose that a battery unit including a plurality of batteries collides to prevent destruction of the battery unit by separating the battery unit from the collision load transmission path. .

  In the invention described in Patent Document 1, an impact-breaking thin-walled portion is formed at the boundary between a battery storage box integrally formed of plastic and an impact-absorbing box, and the impact-breaking thin-walled portion is broken by the impact of a vehicle collision. The shock absorbing box is pushed under the battery storage box to absorb the shock.

  In the invention described in Patent Document 2, a case of a power supply device for a vehicle is constituted by a first case and a second case which are coupled to each other by an impact destruction rivet, and the impact destruction rivet is caused by an impact of a vehicle collision. Is broken, the second case is pushed under the first case to absorb the impact.

  In the invention described in Patent Document 3, the left and right side portions of a square frame-shaped battery frame on which a battery is mounted are fastened to the left and right side members of the vehicle body via bolts extending in the vehicle width direction. When the bolt is broken by a shearing force, the battery frame is moved forward by inertia with respect to the left and right side members to absorb the impact.

JP 2006-306249 A JP 2006-35925 A JP-A-6-108956

  By the way, in the inventions described in the above-mentioned patent documents 1 to 3, it is difficult to accurately break a fracture portion such as an impact fracture thin wall portion, an impact fracture rivet or a bolt at the time of a vehicle collision, and the fracture portion breaks at the time of a crash. Otherwise, the vehicle may break due to the inertial force generated by the acceleration / deceleration of the vehicle or the inertial force generated by road surface unevenness.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to ensure that a battery mounting frame on which a battery is mounted can be reliably separated from a vehicle body only at the time of a vehicle collision.

  In order to achieve the above object, according to the first aspect of the present invention, the support of the vehicle battery unit in which the battery mounting member mounting the battery and the mounting bracket provided on the vehicle frame are fastened by the fastening member. The vehicle is characterized in that a step portion is formed in at least one of the battery mounting member and the mounting bracket so that a portion fastened by the fastening member is thicker than other portions. A support structure for the battery unit is proposed.

  The battery module 12 and the battery cell 13 of the embodiment correspond to the battery of the present invention, the tray 11 of the embodiment corresponds to the battery mounting member of the present invention, and the cross member 15 of the embodiment of the present invention. Corresponding to the frame of the vehicle, the nut 58 and the bolt 59 of the embodiment correspond to the fastening member of the present invention.

  According to the configuration of the first aspect, at least one of the battery mounting member on which the battery is mounted and the mounting bracket provided on the frame of the vehicle, the portion where they are fastened to each other by the fastening member is thicker than the other portions. When the frontal collision of the vehicle, the battery mounting member tries to move forward due to inertia and the vehicle frame tries to move upward due to the impact of the collision. When the bending moment acts, stress concentrates on the stepped portion and breaks. Thereby, since the battery mounting member is separated from the frame of the vehicle, not only the deformation of the battery itself or the high-voltage distribution system in the vicinity of the battery due to the deformation of the vehicle body at the time of the collision can be prevented, but the battery mounting member is pressed against the vehicle body member. It is possible to prevent the occurrence of electrical safety malfunctions such as ground faults. In addition, a load in the front-rear direction is applied to the battery mounting member due to sudden braking or sudden start, or a load in the vertical direction is applied due to unevenness of the road surface. In this case, a large bending moment acts on the fastening portion by the fastening member. Therefore, it is possible to ensure sufficient fatigue strength against these input loads, and there is no possibility that the periphery of the battery mounting member is broken.

The perspective view of the battery unit of an electric vehicle. (First embodiment) The figure which shows the state which removed the battery module from FIG. (First embodiment) FIG. 3 is a three-direction arrow view of FIG. 2. (First embodiment) 4A-4A line sectional view and 4B-4B line sectional view of FIG. (First embodiment) FIG. 5 is a sectional view taken along line 5-5 of FIG. (First embodiment) FIG. 4 is an enlarged view of part 4 of FIG. 2. (First embodiment) The perspective view of a battery module support stand and a power switch support stand. (First embodiment) FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 2. (First embodiment) FIG. 9 is a sectional view taken along line 9-9 in FIG. 3. (First embodiment) FIG. 10 is a sectional view taken along line 10-10 in FIG. 3; (First embodiment) Action explanatory drawing corresponding to FIG. (First embodiment) The schematic diagram explaining the flow path of the air for cooling. (First embodiment) The figure which shows the relationship between the flow direction of cooling air, and the lamination direction of a battery cell. (First embodiment) The figure corresponding to FIG. (Second Embodiment)

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 3, a battery unit that supplies electric power to a motor / generator that is a driving power source for an electric vehicle includes a flat tray 11 and a plurality of trays 11 mounted on the floor surface of the tray 11. And battery modules 12. Each battery module 12 has a rectangular parallelepiped shape, and stores therein a plurality of battery cells 13 (see FIG. 2) electrically connected in series. Two brackets 12a and 12a for fixing the battery module 12 to the tray 11 are provided on both end faces in the longitudinal direction.

  The mounting bracket 14 provided at the front portion of the tray 11 is coupled to the cross member 15 of the vehicle body, and the two mounting brackets 16L and 17L provided at the left rear portion of the tray 11 are coupled to the left side frame 18L. By connecting the two mounting brackets 16R, 17R provided at the right rear part to the right side frame 18R, the battery unit is supported by being suspended from the vehicle body. A fan unit 19 that houses an electric fan (not shown) is provided at the rear end of the tray 11, and when the outside air sucked by the fan unit 19 flows inside the tray 11, the floor surface thereof is provided. The battery modules 12 are cooled by exchanging heat with the battery modules 12.

  The tray 11 includes a first vertical frame member 21, a second vertical frame member 22, a third vertical frame member 23, and a fourth vertical frame member 24 that extend in parallel with each other along the longitudinal direction of the vehicle body. The first vertical frame member 21 is disposed on the right side in the vehicle width direction, the second vertical frame member 22 is disposed on the left side in the vehicle width direction, and the third vertical frame member 23 is disposed on the inner side in the vehicle width direction of the first vertical frame member 21. The fourth vertical frame member 24 is disposed on the inner side in the vehicle width direction of the second vertical frame member 22.

  The tray 11 has a fifth vertical frame member 25, a sixth vertical frame member 26, and a seventh vertical frame member 27 that extend in parallel with each other along the vehicle body longitudinal direction behind the first to fourth vertical frame members 21-24. Is provided. The fifth vertical frame member 25 is disposed on the right side in the vehicle width direction, the sixth vertical frame member 26 is disposed on the left side in the vehicle width direction, and the seventh vertical frame member 27 is disposed in the center of the vehicle body. The eighth vertical frame member 28 is connected in parallel to the outer side of the fifth vertical frame member 25 in the vehicle width direction, and the ninth vertical frame member 29 is connected in parallel to the outer side of the seventh vertical frame member 27 in the vehicle width direction. .

  A first horizontal frame member 31 extending in the vehicle width direction is connected between the front ends of the third and fourth vertical frame members 23 and 24. The second horizontal frame members 32L, 32M, 32R that are divided into three and extend in the vehicle width direction are connected between the front ends of the first and second vertical frame members 21, 22. The fourth vertical frame member 24 is sandwiched between the left and center second horizontal frame members 32L and 32M, and the third vertical frame member 23 is sandwiched between the center and right second horizontal frame members 32M and 32R. The third horizontal frame members 33L, 33M, and 33R that are divided into three and extend in the vehicle width direction are connected between the front and rear intermediate portions of the first and second vertical frame members 21 and 22. The fourth vertical frame member 24 is sandwiched between the left and center third horizontal frame members 33L and 33M, and the third vertical frame member 23 is sandwiched between the center and right third horizontal frame members 33M and 33R.

  A fourth horizontal frame member 34 extending in the vehicle width direction is connected to the rear ends of the first to fourth vertical frame members 21 to 24. Front ends of fifth to seventh vertical frame members 25 to 27 are connected to the fourth horizontal frame member 34, and the front ends of the fifth to seventh vertical frame members 25 to 27 are divided into two and extend in the vehicle width direction. The fifth horizontal frame members 35L and 35R are connected.

  An inlet side leg 42i and an outlet side leg 42o are erected at the front ends of the eighth vertical frame member 28 and the ninth vertical frame member 29, respectively, and between the upper ends of the inlet side leg 42i and the outlet side leg 42o. A rectangular plate-shaped heat exchange panel 43 extending in the vehicle width direction is installed.

  The mounting bracket 14 is fixed to the front surface of the first horizontal frame member 31, the mounting brackets 16L and 16R are fixed to the outer surfaces of the first and second vertical frame members 21 and 22, respectively, and the mounting brackets 17L and 17R are respectively It is fixed to the upper surfaces of the eighth and ninth vertical frame members 28 and 29.

  An inlet duct 19a of the fan unit 19 is fixed to an opening 29c formed in the rear upper surface of the ninth vertical frame member 29, and the two outlets 19b and 19b of the fan unit 19 open toward the left and right rear of the vehicle body.

  Next, the flow path of air as the refrigerant flowing inside the tray 11 will be described. The overall configuration of the air flow path is schematically shown in FIG.

  As shown in FIGS. 3 and 12, the first vertical frame member 21, the second vertical frame member 22, the fifth vertical frame member 25, and the sixth vertical frame member 26 are all made of extruded materials having the same cross-sectional shape. Is done. As shown in FIG. 4A, the cross section of the first vertical frame member 21 is “L” -shaped, and the upper hollow frame F and the lower first duct D1 are integrally formed. The second vertical frame member 22, the fifth vertical frame member 25, and the sixth vertical frame member 26 having the same cross-sectional shape are disposed below the hollow frame F, respectively, with the second duct D2, the eighth duct D8, and the ninth duct. A duct D9 is provided. An eleventh duct D11 is formed inside the ninth vertical frame member 29.

  As shown in FIGS. 3 and 12, the third vertical frame member 23, the fourth vertical frame member 24, and the seventh vertical frame member 27 are all made of extruded materials having the same cross-sectional shape. As shown in FIG. 4B, the cross section of the third vertical frame member 23 has a “convex” shape, and a hollow frame F is provided on the upper side and a pair of second frames arranged in the vehicle width direction on the lower side. Three ducts D3 and D3 are integrally formed. The fourth vertical frame member 24 having the same cross-sectional shape is integrally provided with a fourth duct D4 on the left side in the vehicle width direction and a fifth duct D5 on the right side in the vehicle width direction below the hollow frame F. The seventh vertical frame member 27 having the same cross-sectional shape is integrally provided with a pair of left and right seventh ducts D7 and D7 below the hollow frame F.

  As shown in FIGS. 3, 5, and 12, the first horizontal frame member 31, the second horizontal frame members 32L, 32M, and 32R, the fourth horizontal frame member 34, and the fifth horizontal frame members 35L and 35R are all “ It is composed of an extruded material having a “mouth” -shaped cross section. The left second horizontal frame member 32L forms a bypass duct Db (see FIG. 6). The left end of the bypass duct Db is connected to the front end of the second duct D2, and the right end of the bypass duct Db is the fourth vertical length. The flow path forming member 44 that covers the upper surface of the frame member 24 is connected to the opening 24d (see FIG. 6) on the upper surface of the fifth duct D5.

  A heat insulating material such as a foam material may be provided between the flow path forming member 44 and the fourth duct D4, and the heat insulating material has a rectifying function such as unevenness extending from the upper surface opening 24d toward the bypass duct Db. May be given. Thereby, heat exchange between the low-temperature air flowing through the fourth duct D4 and the high-temperature air discharged to the bypass duct Db can be prevented.

  The inside of the fourth horizontal frame member 34 constitutes a sixth duct D6, in which the rear ends of the first and second ducts D1 and D2, the rear end of the fifth duct D5, the eighth and ninth ducts D8 and D9. Are connected to the front end of the eleventh duct D11. The central second horizontal frame member 32M, the right second horizontal frame member 32R, the third horizontal frame members 33L, 33M, 33R and the fifth horizontal frame members 35L, 35R do not function as air flow paths.

  The rear end of the first duct D1, the front end of the eighth duct D8, and the right end of the sixth duct D6 gather at the first gathering portion A (see FIG. 12) of the front portion of the eighth vertical frame member 28, and the second duct D2. The rear end, the front end of the ninth duct D9, the front end of the eleventh duct D11, and the left end of the sixth duct D6 gather at the second collecting portion B (see FIG. 12) at the front portion of the ninth vertical frame member 29. As shown in FIGS. 2 and 3, the inlet-side leg portion 42i of the battery module support base 41 is connected to the opening 29a above the first collecting portion A, and the battery module support is supported to the opening 28a above the second collecting portion B. The exit side leg part 42o of the base 41 is connected. A rectangular plate-shaped heat exchange panel 43 extending in the vehicle width direction is installed between the upper ends of the entrance leg 42i and the exit leg 42o, and a tenth duct D10... Is formed inside the heat exchange panel 43. The

  Suction ports 23a, 23a are formed at the front ends of the pair of third ducts D3, D3 of the third vertical frame member 23, and a suction port 24a is formed at the front end of the fourth duct D4 of the fourth vertical frame member 24. Suction ports 27 a and 27 a are formed at the rear ends of the pair of seventh ducts D 7 and D 7 of the vertical frame member 27.

  The third vertical frame member 23 and the first vertical frame member 21 are connected by two heat exchange panels 45, 45, and the fourth vertical frame member 24 and the second vertical frame member 22 are two heat exchange panels 45, 45. The third vertical frame member 23 and the fourth vertical frame member 24 are connected by three heat exchange panels 45... And the seventh vertical frame member 27 and the fifth vertical frame member 25 are connected by the heat exchange panel 45. Then, the seventh vertical frame member 27 and the sixth vertical frame member 26 are connected by the heat exchange panel 45.

  As shown in FIG. 5, a large number of connecting ducts Dc are formed in each heat exchange panel 45 by a large number of partition walls 45 a extending along the air flow direction. A large number of communication holes 21b to 27b are formed on the side surfaces of the first to seventh vertical frame members 21 to 27, and the internal spaces of the first to seventh vertical frame members 21 to 27 are connected to the communication holes 21b. It communicates with the internal space of the connecting duct Dc.

  As shown in FIGS. 1 and 4, two or four battery modules 12 are supported on the upper surface of each heat exchange panel 45, and four brackets 12a of each battery module 12 are bolts 46 and nuts. 47... Are fixed to the first to seventh vertical frame members 21 to 27 and the first and second horizontal frame members 31 and 32M. At this time, as shown in FIGS. 4 and 5, a silicon sheet 48 having high heat conductivity is sandwiched between the lower surface of the battery module 12 and the upper surface of the heat exchange panel 45, and the upper surface of the heat exchange panel 45 is mutually attached. A number of air vent grooves 45b extending in parallel are formed.

  As shown in FIGS. 1 and 12, the eight battery modules 12 arranged between the first and third vertical frame members 21 and 23 constitute the first battery group B1, and the second and fourth vertical frames. The eight battery modules 12 arranged between the members 22 and 24 constitute the second battery group B2, and the ten battery modules 12 arranged between the third and fourth vertical frame members 23 and 24 are The three battery modules 12 constituting the third battery group B3 and arranged between the fifth and seventh vertical frame members 25, 27 constitute the fourth battery group B4, and the sixth and seventh vertical frame members. The three battery modules 12 arranged between 26 and 27 constitute the fifth battery group B5, and the two battery modules 12 and 12 arranged on the battery module support base 41 constitute the sixth battery group B6. Constitute

  As shown in FIGS. 2, 7 and 8, the battery module support base 41 is formed between the inlet-side leg 42i and the outlet-side leg 42o that are hollow, and between the inlet-side leg 42i and the outlet-side leg 42o. And a plate-like heat exchange panel 43 erected. The entrance leg 42i is fixed with bolts 49 so as to cover the opening 28a (see FIG. 3) formed on the front upper surface of the eighth vertical frame member 28, and the exit leg 42o is the ninth vertical frame member 28. It fixes with the volt | bolt 50 ... so that the opening 29a (refer FIG. 3) formed in the front upper surface of the frame member 29 may be covered. In the heat exchange panel 43, a plurality of tenth ducts D10 are partitioned by a plurality of partition walls 43a extending in the air flow direction. Air vent grooves 43b are formed on the upper surface of the heat exchange panel 43, and the two battery modules 12 and 12 constituting the sixth battery group B6 are placed on the upper surface with the silicon sheet 48 interposed therebetween.

  A power switch support base 51 made of a metal pipe bent behind the battery module support base 41 is provided. The power switch support base 51 includes a rectangular support frame 51a that supports the power switch 52 and a pair of left and right support legs 51b and 51c extending downward from the left and right rear ends thereof. A plurality of brackets 51d provided on the front edge of the support frame 51a are fixed to the rear edge of the heat exchange panel 43 with bolts 53, and a mounting bracket 51e provided on the lower end of the left support leg 51b is provided with a bolt 54 in the ninth vertical direction. A mounting bracket 51f fixed to the upper surface of the frame member 29 and provided at the lower end of the right support leg 51c is fixed to the upper surface of the eighth vertical frame member 28 with bolts 55. The mounting bracket 51f may be fixed to the bolt 46 that holds the battery module 12 together with the battery module 12.

  A mounting bracket 51e at the lower end of the left support leg 51b extending linearly downward is bent at a right angle toward the rear of the vehicle body. On the other hand, the mounting bracket 51f at the lower end of the right support leg 51c that extends downward while curving toward the front of the vehicle body is bent at a right angle toward the front of the vehicle body.

  As shown in FIG. 9, drain holes 23c, 24c,... Facing the upper surface of the heat transfer panel 45 are formed on the left and right side surfaces of the hollow frames F, F of the third and fourth vertical frame members 23, 24. Is done. A plurality of drain holes 23c,..., 24c... Are formed at predetermined intervals along the longitudinal direction of the third and fourth vertical frame members 23, 24. The drain holes 23c,. The inside and outside of the hollow frames F, F of the fourth vertical frame members 23, 24 communicate with each other.

  Further, a drain pipe 57 is provided at the rear end portion of the third vertical frame member 23 so as to vertically penetrate the third duct D3, and the fourth duct D4 is provided vertically at the rear end portion of the fourth vertical frame member 24. A drain pipe 57 is provided therethrough. The upper ends of the drain pipes 57, 57 are press-fitted into the upper walls of the third and fourth ducts D3, D4, and the lower ends are welded to the lower walls of the third and fourth ducts D3, D4. By these drain pipes 57, 57, the internal spaces of the hollow frames F, F of the third and fourth vertical frame members 23, 24 communicate with the external space below the third and fourth ducts D3, D4.

  As shown in FIGS. 6 and 10, the first horizontal frame member 31 constituting the front edge of the tray 11 has a “mouth” -shaped cross section, and three openings 31b formed in the front wall 31a thereof. Three nuts 58 are fixed to. The lower flange portion 14a of the lower end of the mounting bracket 14 extending obliquely from the front upper side to the rear lower side contacts the front surface of the first horizontal frame member 31, and three bolts 59 penetrating the lower flange portion 14a are nuts 58. ... to be concluded. The dashboard lower panel 60 arranged at the front of the vehicle body extends from the front upper side to the rear lower side, and the cross member 15 extending in the vehicle width direction is coupled to the lower end thereof. The upper flange portion 14 b at the upper end of the mounting bracket 14 is in contact with the lower surface of the cross member 15 and is fastened by two bolts 61 and 61 and two nuts 62 and 62.

  The front wall 31a of the first horizontal frame member 31 is provided with a step portion 31c extending horizontally in the upper part of the opening 31b, and the thickness of the front wall 31a is thick below the step portion 31c and above the step portion 31c. It is getting thinner.

  As shown in FIGS. 1, 4B, and 10, the outer periphery of the battery cover 63 that covers the upper surface of the battery unit of the electric vehicle is fixed to the outer periphery of the tray 11 with bolts 64 and nuts 65. . The lower surface of the tray 11 is covered with an under cover 66.

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

  When the motor / generator, which is a driving source for driving the vehicle, is driven / regenerated, the battery modules 12 ... that are the power source generate heat. Therefore, the battery modules 12 ... are cooled by the air (outside air) flowing inside the tray 11. It is necessary to ensure durability. The battery cells 13 and the battery modules 12 do not directly contact the outside air for cooling and are indirectly cooled by the outside air flowing through the first to seventh ducts D1 to D7. The cells 13 and the battery modules 12 do not get dirty.

  When the fan unit 19 at the downstream end of the air flow path is driven, air is sucked from the suction ports 23a, 23a; 24a at the front ends of the third and fourth vertical frame members 23, 24 as shown in FIG. . The air sucked into the third duct D3 from the right suction port 23a of the third vertical frame member 23 is connected to the heat exchange panels 45, 45 below the first battery group B1 from the right side surface of the third duct D3. After flowing into Dc and flowing therethrough, the first battery group B1 is cooled by exchanging heat, and then flows into the first duct D1 of the first vertical frame member 21 and collects in the first collecting portion A behind.

  The air sucked into the fourth duct D4 from the suction port 24a of the fourth vertical frame member 24 enters the connection duct Dc of the heat exchange panels 45, 45 below the second battery group B2 from the left side surface of the fourth duct D4. After flowing in and flowing through it, the second battery group B2 is cooled by exchanging heat, and then flows into the second duct D2 of the second vertical frame member 22 and collects in the rear second collecting portion B.

  The air sucked into the third duct D3 from the left suction port 23a of the third vertical frame member 23 is connected to the heat exchange panel 45 ... below the third battery group B3 from the left side surface of the third duct D3. Then, heat is exchanged while flowing therethrough to cool the third battery group B3, and then flows into the fifth duct D5 of the fourth vertical frame member 24 to be branched back and forth. A part of the air in the fifth duct D5 passes through the opening 24d on the upper surface of the fifth duct D5 and the inside of the flow path forming member 44 and flows into the bypass duct Db inside the left second horizontal frame member 32L. To the front end of the second duct D2 of the second vertical frame member 22 and gather in the first collecting portion A behind. Further, the remaining air in the fifth duct D5 flows rearward and flows into the sixth duct D6 of the fourth horizontal frame member 34, where it is divided into left and right and gathers in the first collecting part A and the second collecting part B.

  The air sucked into the seventh ducts D7, D7 from the suction ports 27a, 27a at the rear end of the seventh vertical frame member 27 undergoes heat exchange below the fourth battery group B4 from the right side surface of the right seventh duct D7. After flowing into the connecting duct Dc of the panel 45 and heat exchange while flowing therethrough to cool the fourth battery group B4, it flows into the eighth duct D8 of the fifth vertical frame member 25 and flows forward, While gathering in the gathering part A, it flows into the connection duct Dc of the heat exchange panel 45 below the fifth battery group B5 from the left side surface of the seventh duct D7 on the left side, and heat exchange is performed while flowing there through the fifth battery. After the group B5 is cooled, it flows into the ninth duct D9 of the sixth vertical frame member 26, flows forward, and gathers in the second collecting portion B.

  The air gathered in the first gathering part A passes through the opening 28a on the upper surface of the eighth vertical frame member 28, flows upward in the inlet side leg part 42i, and enters the tenth duct D10 in the heat exchange panel 43. After flowing in and flowing through it to exchange heat and cool the sixth battery group B6, it flows downward through the outlet leg 42o and passes through the opening 29a on the upper surface of the ninth vertical frame member 29. , Gather in the second gathering part B. The air flowing through the tenth duct D10 in the heat exchange panel 43 has already undergone heat exchange with the first and fifth battery groups B1 to B5, and the temperature has risen to some extent. Since all the air gathered in the first gathering part A flows, the cooling performance of the sixth battery group B6 can be ensured with a sufficient flow rate of air.

  Since the silicon sheet 48 sandwiched between the battery module 12 and the heat exchange panel 45 is softer than the battery module 12 and the heat exchange panel 45, the silicon sheet 48 is deformed by the weight of the battery module 12 and the battery module 12 and the heat exchange panel 45 Adhering to both, the function of increasing the heat exchange efficiency from the battery module 12 to the heat exchange panel 45 is exhibited. In addition, a large number of air vent grooves 45b extending in parallel to each other are formed on the upper surface of the heat exchange panel 45, and air is sandwiched between the heat exchange panel 45 and the silicon sheet 48 by the air vent grooves 45b. It can prevent that heat exchange efficiency falls.

  Effects of the heat exchange panel 43 of the battery module support base 41 and the silicon sheet 48 sandwiched between the battery modules 12 and 12, and the effects of the air vent grooves 43b on the upper surface of the heat exchange panel 43 of the battery module support base 41 Is the same as described above.

  Incidentally, the air flowing inside the pair of third ducts D3 and D3 formed so as to be in contact with the third vertical frame member 23 is low-temperature before heat exchange. Of the fourth duct D4 and the fifth duct D5 formed so as to be in contact with each other, low-temperature air before heat exchange flows through the fourth duct D4, and high-temperature air after heat exchange flows through the fifth duct D5. Therefore, there is a possibility that heat exchange is performed between air having a temperature difference, and the cooling effect of the battery modules 12 of the second battery group B2 may be reduced.

  However, according to this embodiment, since the fifth duct D5 communicates with the second duct D2 via the bypass duct Db, the time during which the high-temperature air after heat exchange stays inside the fifth duct D5 is increased. By shortening and making it difficult to exchange heat with the low-temperature air in the fourth duct D4, the temperature rise of the air in the fourth duct D4 is minimized and the cooling effect of the second battery group B2 is reduced. Can be minimized.

  All of the battery modules 12 except the two battery modules 12, 12 of the third battery group supported at the front end of the tray 11 are arranged so that cooling air flows along the longitudinal direction thereof. The In other words, the cooling air is arranged in the battery cells 13 of each battery module 12 so as to flow in parallel with the stacking direction.

  FIG. 13A shows a comparative example, and corresponds to the case where the stacking direction of the battery cells 13 of each battery module 12 is orthogonal to the air flow direction, contrary to the above. In this case, the temperature of the air varies depending on the position where the air flows from the vertical frame member to the heat exchange panel, and the air A that changes direction on the upstream side and flows into the heat exchange panel is low temperature, but the direction on the downstream side Since the air C that is converted and flows into the heat exchange panel becomes high temperature, the battery cell 13 that exchanges heat with the air A, the battery cell 13 that exchanges heat with the air B, and the battery cell 13 that exchanges heat with the air C. However, the temperature of the cooling air differs and the temperature varies between the battery cells 13..., Which makes it difficult for the battery cells on the downstream side to be cooled with respect to the battery cells on the upstream side.

  On the other hand, FIG. 13B shows the present embodiment, and corresponds to the case where the stacking direction of the battery cells 13 of each battery module 12 is parallel to the air flow direction. In this case, each of the battery cells 13... Is in contact with each of the upstream low-temperature air A, the middle-stream medium-temperature air B, and the downstream-side high-temperature air C to exchange heat, so that the air A, B, C The temperature variation is made uniform in each battery cell 13... And the temperature difference is made uniform by uniformly cooling all the battery cells 13.

  Further, since the battery module support base 41 has the two heavy battery modules 12 mounted on the upper surface of the heat exchange panel 43 supported by the inlet side leg part 42i and the outlet side leg part 42o, the vehicle suddenly moves. A moment to cause the battery module support base 41 to fall is generated by an inertial force acting on the battery modules 12 when starting, sudden braking or sudden turning. In particular, since the entrance leg 42i and the exit leg 42o are spaced apart from each other in the vehicle width direction and have a small width in the front-rear direction, the battery module support base 41 when the vehicle suddenly starts and suddenly brakes. Tends to fall in the front-rear direction.

  However, according to the present embodiment, since the power switch support base 51 is connected to the rear part of the battery module support base 41, the power switch support base 51 increases the falling rigidity of the battery module support base 41 and makes a sudden start. In addition, stability during sudden braking can be increased. In particular, the power switch support base 51. Since the mounting bracket 51e of the left support leg 51b extends rearward of the vehicle body, the right support leg 51c bends forward of the vehicle body and the mounting bracket 51f extends forward of the vehicle body. The rigidity of the battery module support base 41 can be increased and thus the rigidity of the battery module support base 41 falling in the front-rear direction can be increased. Moreover, since the power module support base 51 is used to increase the falling rigidity of the battery module support base 41, a special reinforcing member is not required, and the number of parts and cost can be reduced.

  Further, the heat exchange panel 43 of the battery module support base 41 arranged above the lower fourth and fifth battery groups B4, B5 and supporting the upper sixth battery group B6 on the upper surface is configured to be hollow. Since the upper sixth battery group B6 is cooled by the air flowing through the inner tenth duct D10 ..., the heat exchange panel 43 has two functions of supporting the sixth battery group B6 and cooling the sixth battery group B6. By providing it, the number of parts can be reduced and the structure can be simplified.

  Moreover, since the inside of the heat exchange panel 43 is divided into a plurality of tenth ducts D10 by a plurality of partition walls 43a extending in the air flow direction, the heat exchange panel 43 is crushed by the weight of the sixth battery group B6. In addition to preventing the air flow path, the air flowing inside the heat exchange panel 43 can be rectified by the partition walls 43a to reduce the flow resistance. The heat exchange panels 45 that support the first to fifth battery groups B1 to B5 also achieve the above-described effects by the partition walls 45a as well as the heat exchange panel 43 that supports the sixth battery group B6. can do.

  Further, if water accumulates on the floor surface of the tray 11 due to dew condensation or water immersion, the battery module 12 may get wet with the water and the durability may be lowered. However, the heat exchange panel 45 constituting the floor surface of the tray 11. The water accumulated on the upper surface of the gas flows into the hollow frames F, F from the drain holes 23c ..., 24c ... (see Fig. 9) formed in the third and fourth vertical frame members 23, 24, and from there the third Further, since the water is discharged to the lower surface of the tray 11 through the drain pipes 57, 57 that vertically penetrate the fourth ducts D3, D4, it is possible to prevent deterioration of the battery modules 12 due to adhesion of moisture. Further, since the labyrinth is constituted by the drain pipes 57, 57, the hollow frames F, F, and the drain holes 23c, 24c, the water is prevented from entering the tray 11 side from the drain pipes 57, 57 side. In addition to the fact that the third and fourth vertical frame members 23 and 24 are used for drainage, an increase in the number of parts and a complicated structure can be prevented.

  In addition, since the third to fifth ducts D3 to D5 are integrally formed on the lower surfaces of the hollow frames F and F of the third and fourth vertical frame members 23 and 24, the hollow frame is formed by the third to fifth ducts D3 to D5. In addition to reinforcing the F and F to further increase the rigidity of the tray 11, the drain pipes 57 and 57 penetrate the third and fourth ducts D3 and D4 from the top to the bottom. 57 can increase the rigidity of the third and fourth ducts D3 and D4 with respect to the load in the vertical direction.

  Furthermore, since the drain pipes 57 and 57 are located at the downstream end of the third and fourth ducts D3 and D4 in the air flow direction, the air flow in the third and fourth ducts D3 and D4 is water. It is possible to minimize obstruction by the extraction pipes 57, 57. Even if the drain pipes 57 and 57 are provided only at the rear ends of the third and fourth ducts D3 and D4, the water in the third and fourth ducts D3 and D4 is inertial when the vehicle starts or accelerates. Because it flows backward, the discharge is performed without any problem.

  Furthermore, since the lower ends of the drainage pipes 57 and 57 are opened so as to face the upper surface of the under cover 66 that covers the lower surface of the tray 11, muddy water or the like that repels the wheels as the vehicle travels is It is possible to prevent intrusion into the third and fourth ducts D3 and D4 through the shielding and drainage pipes 57 and 57.

  The drainage structure provided on the third and fourth vertical frame members 23 and 24 in order to prevent the first to third battery groups B1 to B3 from getting wet has been described above, but the fourth and fifth battery groups B4 are described. , B5 may be provided with the same water draining structure of the seventh vertical frame member 27 in order to prevent water wetting.

  As shown in FIG. 11, when the vehicle collides with the front, the heavy battery unit moves forward with inertial force (see arrow A1), and the dashboard lower panel 60, the cross member 15 and the attachment are attached by crushing the front of the vehicle body. Since the bracket 14 is deformed so as to be pulled upward (see arrow A2), a large bending moment M is applied to the mounting bracket 14 whose upper end is fixed to the cross member 15 and whose lower end is fixed to the first horizontal frame member 31 of the tray 11. Works. At this time, the step wall 31c whose strength suddenly changes is formed on the front wall 31a of the first horizontal frame member 31 in which the lower flange portion 14a of the mounting bracket 14 is coupled by the bolt 59 and the nut 58. When the step portion 31 c is broken by the bending moment M, the nuts 58 are separated from the first horizontal frame member 31 and the front end of the tray 11 is separated from the mounting bracket 14.

  When the front end of the tray 11 is separated from the mounting bracket 14 in this manner, the rear portion of the tray 11 is suspended and supported on the side frames 18L and 18R by the mounting brackets 16L and 16R; 17L and 17R, and the body member is deformed. And can be separated. As a result, the battery unit and the surrounding high-voltage power distribution system are deformed by being pulled by the deformation of the front part of the vehicle body, or are pressed against the vehicle body member located above to cause electrical safety problems such as ground faults. An event can be prevented from occurring.

  Even during normal driving of the vehicle, the inertial force acts in the front / rear / left / right or up / down direction due to sudden start, sudden braking, sudden turn, overcoming road surface irregularities, etc. The bending moment M is not generated because the lower panel 60 is not deformed upward (see arrow A2), and therefore the step portion 31c is not broken.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  In the first embodiment, the stepped portion 31c is formed on the front wall 21a of the first horizontal frame member 31 where the stress concentrates and breaks at the time of a frontal collision of the vehicle. In the second embodiment, the stepped portion is provided. The portion 14c is provided at the base of the lower flange 14a of the mounting bracket 14, and the thickness of the lower flange 14a fastened by the bolts 59 and nuts 58 is made thicker than the other portions.

  Also according to the second embodiment, the bending moment M generated at the time of a frontal collision of the vehicle concentrates the stress on the stepped portion 14c of the mounting bracket 14 and breaks it securely, and the front portion of the tray 11 is separated from the cross member 15. be able to.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, the first horizontal frame member 31 and the mounting bracket 14 are fastened with bolts 59... And nuts 58... As fastening means, but any other arbitrary fastening means may be adopted. it can.

11 Tray (battery mounting member)
12 Battery module (battery)
13 Battery cell (battery)
14 Mounting bracket 14c Step 15 Cross member (vehicle frame)
31c Stepped portion 58 Nut (fastening member)
59 Bolt (fastening member)

Claims (1)

A vehicle battery unit support structure in which a battery mounting member on which a battery is mounted and a mounting bracket provided on a vehicle frame are fastened by a fastening member,
At least one of the battery mounting member and the mounting bracket is formed with a stepped portion so that a portion fastened by the fastening member is thicker than the other portion. .

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