Battery structure for an electric vehicle
A vehicle structure includes a battery tray disposed at a lower portion of a center of a vehicle body, and a cross member extending in a vehicle width direction and inserted into the battery tray. The battery tray includes a first bottom portion, a peripheral wall erected on an outer periphery of the first bottom portion, a first inner wall connected to the first bottom portion, a second inner wall connected to the first bottom portion, and a second bottom portion connected to both the first inner wall and the second inner wall and raised from the first bottom portion, which are configured with an integrally molded fiber-reinforced plastic. A recessed portion extending in the vehicle width direction is formed by the first inner wall, the second inner wall, and the second bottom portion. The cross member is inserted into at least one location of the recessed portion.
1 . A battery structure comprising
a battery tray disposed at a lower portion of a center of a vehicle body, and a cross member extending in a vehicle width direction, which is inserted into the battery tray,
wherein
(1) the battery tray includes a first bottom portion, a peripheral wall erected on an outer periphery of the first bottom portion, a first inner wall connected to the first bottom portion, a second inner wall connected to the first bottom portion, and a second bottom portion connected to both the first inner wall and the second inner wall and raised from the first bottom portion,
(2) the first bottom portion, the peripheral wall, the first inner wall, the second inner wall, and the second bottom portion are configured with an integrally molded fiber-reinforced plastic,
(3) a recessed portion extending in the vehicle width direction is formed by the first inner wall, the second inner wall, and the second bottom portion, and the cross member is inserted into at least one location of the recessed portion, and
(4) wherein discontinuous fibers are continuously dispersed in a boundary area between the first bottom portion and the first inner wall, a boundary area between the first bottom portion and the second inner wall, and a boundary area between the first bottom portion and the peripheral wall.
2 . The battery structure according to claim 1 , wherein the cross member is bent in a protruding shape along the recessed portion.
3 . The battery structure according to claim 2 , wherein the cross member is formed by pressing and bending a flat metal plate to have a protruding shape along the recessed portion.
4 . The battery structure according to claim 1 , wherein the cross member has a thickness of 0.5 mm or more and 6.0 mm or less.
5 . The battery structure according to claim 1 , wherein a space is provided between the cross member and the second bottom portion.
6 . The battery structure according to claim 1 , wherein the cross member is fitted into the recessed portion.
7 . The battery structure according to claim 1 , wherein the structure includes a plurality of cross members.
8 . The battery structure according to claim 1 , wherein the cross member is made of metal or a continuous fiber-reinforced composite material.
9 . The battery structure according to claim 1 , wherein the battery tray is configured with a fiber-reinforced plastic integrally molded using a sheet molding compound.
10 . The battery structure according to claim 9 , wherein a weight average fiber length of the reinforcing fibers contained in the fiber-reinforced plastic is 1 mm or more.
11 . The battery structure according to claim 1 , wherein a closed cross section structure is formed by the first inner wall, the second inner wall portion, the second bottom portion, and the cross member when a cross section of the structure is observed from the vehicle width direction.
12 . The battery structure according to claim 1 , wherein a natural frequency of the battery tray in a primary mode is 25 Hz or more.
13 . The battery structure according to claim 1 , wherein a rib integrally molded with the battery tray is provided in at least one location of the recessed portion.
14 . The battery structure according to claim 1 , wherein an angle formed by the first bottom portion and the first inner wall and an angle formed by the first bottom portion and the second inner wall are 90 degrees or more and 135 degrees or less.
15 . The battery structure according to claim 1 , wherein a rib or a boss for fixing a battery is provided on an upper surface of the first bottom portion.
16 . The battery structure according to claim 1 , wherein at least one of the first inner wall and the second inner wall has a shape following a battery shape.
17 . The battery structure according to claim 1 , wherein the first inner wall and the second inner wall extend at least along the vehicle width direction.
18 . The battery structure according to claim 1 ,
wherein the battery tray includes a stud bolt base connected to both the first inner wall and the second inner wall and raised from a first bottom portion, and
the stud bolt base is configured with a fiber-reinforced plastic integrally molded with the first bottom portion, the peripheral wall, the first inner wall, the second inner wall, and the second bottom portion.
19 . The battery structure according to claim 18 , wherein a stud bolt for attaching a battery bracket is provided on the stud bolt base.
20 . The battery structure according to claim 19 , wherein the stud bolt base includes a non-penetrating insertion hole, and the stud bolt is inserted into the insertion hole.
21 . A battery tray disposed in a lower portion of a center of a vehicle body, wherein
(1) the battery tray comprises a first bottom portion, a peripheral wall erected on an outer periphery of the first bottom portion, a first inner wall connected to the first bottom portion, a second inner wall connected to the first bottom portion, and a second bottom portion connected to both the first inner wall and the second inner wall and raised from the first bottom portion,
(2) the first bottom portion, the peripheral wall, the first inner wall, the second inner wall, and the second bottom portion are configured with an integrally molded fiber-reinforced plastic,
(3) a recessed portion extending in a vehicle width direction is formed by the first inner wall, the second inner wall, and the second bottom portion,
(4) a rib integrally molded with the battery tray is provided in at least one location of the recessed portion, and
(5) wherein discontinuous fibers are continuously dispersed in a boundary area between the first bottom portion and the first inner wall, a boundary area between the first bottom portion and the second inner wall, and a boundary area between the first bottom portion and the peripheral wall.
22 . The battery tray according to claim 21 , wherein a natural frequency of the battery tray in a primary mode is 25 Hz or more.
23 . The battery structure according to claim 1 , further comprising an energy absorbing member on an outside of the peripheral wall of the battery tray,
wherein a lowermost part of the energy absorbing member is located at a lower position than a lowermost part of the battery tray.
24 . The battery structure according to claim 23 ,
wherein the lowermost part of the energy absorbing member is below the first bottom portion of the battery tray, and an uppermost portion of the energy absorbing member is above the first bottom portion of the battery tray.
25 . The battery structure according to claim 23 , further comprising a protective wall below the battery tray,
wherein the protective wall is connected to the energy absorbing member.