Search

EP-3744621-B1 - ELECTRIC VEHICLE AND USE OF BATTERY UNIT

EP3744621B1EP 3744621 B1EP3744621 B1EP 3744621B1EP-3744621-B1

Inventors

  • Yamada, Morihide
  • HATANO, KAZUHISA
  • AKUNE, Hisashi
  • TAKAHASHI, MUNENARI

Dates

Publication Date
20260506
Application Date
20200520

Claims (13)

  1. An electric vehicle (V), comprising: a floor panel (2); a pair of right-and-left floor frames (3) provided below the floor panel (2), each of which forms a closed-cross section extending longitudinally cooperatively with the floor panel (2); and a battery unit (10) configured to support plural battery modules (11) and mounted at the pair of floor frames (3), wherein the battery unit (10) comprises a pair of right-and-left side frames (21) attached to the pair of floor frames (3), a cross frame (31, 32, 33) extending in a vehicle width direction and interconnecting the pair of side frames (21), and the plural battery modules (11), the plural battery modules (11) are respectively formed substantially in a rectangular shape in a plan view and have substantially the same size comprising a longitudinal dimension, a lateral dimension, and a height dimension, and the plural battery modules (11) are respectively mounted at the side frames (21) and/or the cross frame (31, 32, 33) and arranged in plural rows (S1, S2, S3) adjacently to each other in the vehicle width direction and/or a vehicle longitudinal direction such that a direction of the longitudinal dimension of the rectangular shape is substantially parallel to the vehicle longitudinal direction or the vehicle width direction, characterized in that the plural battery modules (11) are mounted at the side frames (21) and/or the cross frame (31, 32, 33) by mounting brackets (52, 53), the number of mounting points (52s, 52t, 52u) of the mounting brackets (52) configured to mount the battery modules (11) positioned at a part (S1) of the plural rows (S1, S2, S3) is set to be larger than the number of mounting points (53s, 53t) of the mounting brackets (53) configured to mount the battery modules (11) positioned at another part (S2, S3) of the plural rows (S1, S2, S3), and mounting rigidity of the battery modules (11) positioned at the part (S1) of the plural rows (S1, S2, S3) is different from that of the battery modules (11) positioned at the other part (S2, S3) of the plural rows (S1, S2, S3).
  2. The electric vehicle (V) of claim 1, wherein the plural battery modules (11) are arranged in three or more rows (S1, S2, S3) extending in the vehicle width direction.
  3. The electric vehicle (V) of claim 2, wherein the mounting rigidity of the battery modules (11) positioned at any one-end-side row (S1) of the three or more rows (S1, S2, S3) is set to be different from that of the battery modules (11) positioned at the other row (S2, S3) of the three or more rows (S1, S2, S3).
  4. The electric vehicle (V) of claim 2 or 3, wherein the plural battery modules (11) are arranged in the longitudinal direction in three or more rows (S1, S2, S3).
  5. The electric vehicle (V) of claim 4, wherein the battery modules (11) positioned at a foremost row (S1) of the three or more rows (S1, S2, S3) are arranged in a single-layer state, and the battery modules (11) positioned at a rearmost row (S3) of the three or more rows (S1, S2, S3) are arranged below a kick-up portion of the floor panel (2) in a two-layer state of upper-and-lower two stages.
  6. The electric vehicle (V) of claim 5, wherein the mounting rigidity of the battery modules (11) positioned at the foremost row (S1) is set to be different from that of the battery modules (11) positioned at the other row (S2, S3).
  7. The electric vehicle (V) of claim 4, wherein the battery modules (11) positioned at a foremost row (S1) and a second row (S2) behind the foremost row (S1) of the three or more rows (S1, S2, S3) are arranged in a single-layer state, and the battery modules (11) positioned at another row (S3) behind the second row (S2) are arranged in the two-layer state of the upper-and-lower two stages.
  8. The electric vehicle (V) of claim 7, wherein the mounting rigidity of the battery modules (11) positioned at the foremost row (S1) is set to be different from that of the battery modules (11) positioned at the second row (S2).
  9. The electric vehicle (V) of any of the preceding claims, wherein the mounting rigidity of the battery modules (11) positioned at the part (S1) of the plural rows (S1, S2, S3) is set to be higher than the mounting rigidity of the battery modules (11) positioned at the other part (S2, S3) of the plural rows (S1, S2, S3).
  10. The electric vehicle (V) of any one of the preceding claims, wherein the longitudinal dimension corresponds to a dimension in a longitudinal direction of the rectangular shape, the lateral dimension corresponds to a dimension in a direction perpendicular to the longitudinal direction of the rectangular shape, and/or the height dimension corresponds to a dimension in a vehicle vertical direction perpendicular to the longitudinal direction and the direction perpendicular to the longitudinal direction of the rectangular shape.
  11. The electric vehicle (V) of any one of the preceding claims, wherein the height dimension is perpendicular to the longitudinal dimension and the lateral dimension.
  12. The electric vehicle (V) of any one of the preceding claims, wherein the plural battery modules (11) are respectively mounted at the side frames (21) and/or the cross frame (31, 32, 33) in a same position or in a same posture.
  13. Use of a battery unit (10) for a vehicle (V), wherein the vehicle (V) comprises a floor panel (2), and a pair of right-and-left floor frames (3) provided below the floor panel (2), each of which forms a closed-cross section extending longitudinally cooperatively with the floor panel (2), the battery unit (10) comprising: a pair of right-and-left side frames (21) to be attached to the pair of floor frames (3); a cross frame (31, 32, 33) extending in a vehicle width direction and interconnecting the pair of side frames (21); and plural battery modules (11), wherein the plural battery modules (11) are respectively formed substantially in a rectangular shape in a plan view and have substantially the same size comprising a longitudinal dimension, a lateral dimension, and a height dimension, and the plural battery modules (11) are respectively mounted at the side frames (21) and/or the cross frame (31, 32, 33) and arranged in plural rows (S1, S2, S3) adjacently to each other in the vehicle width direction and/or a vehicle longitudinal direction such that a direction of the longitudinal dimension of the rectangular shape is to be substantially parallel to the vehicle longitudinal direction or the vehicle width direction, characterized in that the plural battery modules (11) are mounted at the side frames (21) and/or the cross frame (31, 32, 33) by mounting brackets (52, 53), the number of mounting points (52s, 52t, 52u) of the mounting brackets (52) configured to mount the battery modules (11) positioned at a part (S1) of the plural rows (S1, S2, S3) is set to be larger than the number of mounting points (53s, 53t) of the mounting brackets (53) configured to mount the battery modules (11) positioned at another part (S2, S3) of the plural rows (S1, S2, S3), and mounting rigidity of the battery modules (11) positioned at the part (S1) of the plural rows (S1, S2, S3) is different from that of the battery modules (11) positioned at the other part (S2, S3) of the plural rows (S1, S2, S3).

Description

The present invention relates to an electric vehicle, particularly comprising a battery unit supporting a battery module and mounted at a pair of floor frames. The present invention also relates to use of a battery unit for a vechicle. The battery unit is arranged in a space below a vehicle-body floor in the electric vehicle, such as a hybrid vehicle or an electric automotive vehicle, because a battery as a driving source of an electric motor (e.g., a motor generator or a motor) for driving wheels has a large capacity. The battery unit generally comprises plural battery modules of combined battery cells, such as lithium ion, a battery case which stores the plural battery modules, frames of the battery case, and others. A battery mounting structure of an electric vehicle disclosed in Japanese Patent Laid-Open Publication No. 2011-251620 comprises a floor panel, a pair of right-and-left floor frames provided below the floor panel, each of which forms a closed-cross section extending longitudinally cooperatively with the floor panel, and a battery unit supporting battery modules and mounted at the pair of floor frames, wherein the battery unit comprises a lower-side cover member mounting the battery modules, an upper-side cover member covering over the lower-side cover member, and frames forming respective skeletons of the lower-side cover member and the upper-side cover member, and part of the plural battery modules are arranged in a front-side area of the frames in such a manner that their longitudinal direction extends in a vehicle width direction and the other part of the plural battery modules are arranged in a rear-side area of the frames in such a manner that their longitudinal direction extends in a vehicle longitudinal direction. Vibration energy caused by a wheel running on a road surface is transmitted to a vehicle-body strength member through a suspension member and then vibrates a panel member, such as a floor panel forming a cabin, in a vehicle steady traveling. Traveling noises, such as drumming noise or road noise, are generated by the above-described vibration of the panel member. The drumming noise is a low-frequency sound of 20 - 50Hz, and the road noise is a middle-frequency sound of 100 - 400Hz. The drumming noise is sometimes called the road noise. These traveling noises, including the drumming noise and the road noise, may be suppressed by adding a damping material or increasing rigidity of a lower vehicle-body (see Japanese Patent Laid-Open Publication No. H10-129369, for example). In the battery mounting structure of the electric vehicle disclosed in the above-described first patent document, since the plural battery modules are arranged such that a longitudinal direction of the battery modules provided at a front-side first mounting portion corresponds to (matches) the vehicle width direction and a longitudinal direction of the battery modules provided at a rear-side second mounting portion corresponds to (matches) the vehicle longitudinal direction, a size of the battery unit becomes so large that a large space for arranging the battery unit may be required. Herein, it may be possible to minimize its arrangement space by mounting the plural battery modules at the vehicle body, particularly below the floor panel, such that the battery modules are arranged in plural rows and in the same position in three directions of the vehicle width direction, the vehicle longitudinal direction, and the height direction. However, in a case where the plural battery modules are arranged in the same position and in the plural rows as described above, there is a concern that since each of the battery modules has substantially the same natural frequency, all of these battery modules so resonate with vehicle-body vibration at a specified frequency band that the vehicle-body vibration may be improperly amplified. In a case where they resonate with the vehicle-body vibration at a middle-frequency band of 100 - 400Hz, there is a concern that the road-noise performance may be deteriorated. That is, it may not be easy to reduce the traveling noises, securing compactness of the battery unit. US 2014/374180 A1 describes a structure for mounting a battery pack on a vehicle in which a battery case housing a plurality of batteries arranged along a fore-and-aft direction of the vehicle is disposed beneath a floor panel, and power of the plurality of batteries is supplied to a control device of an electric motor by connecting an internal cable disposed within the battery case and an external cable disposed outside the battery case in a cable lead out part provided on the battery case. EP 2 072 308 A2 describes that a battery unit mounted in an electric vehicle is provided with a battery case and a plurality of battery modules. The battery case includes a tray member on the lower side and a cover member on the upper side. The tray member is fixed to side members by a beam member extending in a width direction of a veh