JP2019162908A - Electric vehicle - Google Patents

Abstract

To provide an electric vehicle that easily absorbs the energy generated when it collides with an obstacle or the like.SOLUTION: An electric vehicle 10 includes an air bag 40 that is provided on a battery pack 30 and is configured to be deployable, a fixing member 50 that fixes the battery pack 30 to a vehicle body 20 in a detachable manner, and a control device 60 that controls the air bag 40 and the fixing member 50. The control device 60 includes an air bag control part 64 that deploys the airbag 40 when a collision with an obstacle is estimated, and a fixing member control part 70 that separates the battery pack 30 from the vehicle body 20 by releasing fixation of the battery pack 30 when energy F due to the collision with the obstacle is estimated to be a predetermined value or more.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an electric vehicle.

  In recent years, secondary batteries such as lithium ion secondary batteries are used for driving portable power sources such as personal computers and portable terminals, and electric vehicles such as electric vehicles (EV), hybrid vehicles (HV), and plug-in hybrid vehicles (PHV). It is suitably used for a power supply or the like.

  2. Description of the Related Art Secondary power batteries generally have a battery stack in which a plurality of single cells (battery cells) are connected and a case for accommodating the battery stack in order to increase output in the use of a power source for driving an electric vehicle. Used in the form of a battery pack. For example, Patent Document 1 discloses an electric vehicle in which a battery pack having a plurality of batteries and a battery box that accommodates a battery is detachably supported by a pair of left and right side frames.

JP-A-11-180172 JP 2010-153117 A Japanese Patent Laid-Open No. 10-016689 JP 2004-338558 A

  By the way, the battery pack generally has a property that it is difficult to absorb energy generated when the electric vehicle collides with an obstacle or the like. For this reason, for example, when the battery pack is disposed under the floor, it is difficult to absorb the energy at the time of the collision with respect to the collision from the side of the electric vehicle. For example, when the battery pack is disposed at the rear part of the vehicle body, it is difficult to absorb the energy at the time of the collision with respect to the collision from behind the electric vehicle. Furthermore, since the energy generated when the electric vehicle collides with an obstacle or the like is easily input to the battery pack, the battery pack can be crushed. If the rigidity of the case is increased in order to prevent the battery pack from being crushed, the weight of the battery pack increases and the fuel consumption may decrease. Patent Documents 2 to 4 disclose technologies relating to airbags.

  This invention is made | formed in view of this point, The objective is to provide the electric vehicle which is easy to absorb the energy produced when it collides with an obstruction.

  An electric vehicle according to the present invention includes a vehicle body, a battery stack arranged in a predetermined direction in a state where a plurality of chargeable / dischargeable cells are electrically connected, and a case for housing the battery stack. A battery pack disposed on the vehicle body, an airbag provided on the battery pack and configured to be deployable, a fixing member that removably fixes the battery pack to the vehicle body, the airbag, and A control device that controls the fixing member, and the control device deploys the airbag to protect the battery pack when a collision with an obstacle is estimated, and an obstacle. A fixing member control unit for separating the battery pack from the vehicle body by releasing the fixing of the battery pack when the energy due to the collision with the object is estimated to be equal to or higher than a predetermined value. That.

  According to the electric vehicle of the present invention, the fixing member control unit separates the battery pack from the vehicle body by releasing the fixing of the battery pack when the energy due to the collision with the obstacle is estimated to be equal to or higher than a predetermined value. Thereby, the space in which the battery pack is disposed can be effectively used as a crushable zone, and energy transmitted to the electric vehicle can be effectively absorbed at the time of collision with an obstacle. The airbag control unit deploys the airbag to protect the battery pack when a collision with an obstacle is estimated. Thereby, the energy input into the battery pack can be reduced, and the collapse of the battery pack can be suppressed.

1 is a side view schematically showing an electric vehicle according to an embodiment. It is a block diagram of the electric vehicle which concerns on one Embodiment. It is a side view which shows typically the state by which the battery pack is being fixed with respect to the vehicle body. It is a side view which shows typically the state which the airbag is expand | deployed. It is a side view which shows typically the state by which the battery pack was cut away from the vehicle body. It is the flowchart which showed the procedure of operation | movement of the electric vehicle when the collision with an obstacle is estimated.

  Hereinafter, preferred embodiments of the present invention will be described. Note that matters other than matters specifically mentioned in the present specification and necessary for the implementation of the present invention can be grasped as design matters of those skilled in the art based on the prior art in this field. The present invention can be carried out based on the contents disclosed in this specification and common technical knowledge in the field. In addition, each drawing is drawn typically and does not necessarily reflect a real thing. Each drawing shows only an example, and each drawing does not limit the present invention unless otherwise specified.

  As shown in FIG. 1, the electric vehicle 10 includes a vehicle body 20, a battery pack 30, an airbag 40, a fixing member 50, and a control device 60 (see FIG. 2). Reference numerals F, Rr, U, and D in the drawings mean front, rear, upper, and lower, respectively. However, the above direction is only a direction determined for convenience of description, and does not limit the installation mode of the battery pack 30 or the like, and does not limit the present invention.

  As shown in FIG. 1, the battery pack 30 is disposed below the rear seat of the vehicle body 20, and is fixed to the floor panel 22 (see FIG. 3A). The battery pack 30 is disposed so as to close the opening 24 (see FIG. 3A) formed in the floor panel 22. Battery pack 30 is arranged outside the passenger compartment. The battery pack 30 may be disposed at a position other than the lower side of the rear seat.

  As shown in FIG. 2, the battery pack 30 includes a battery stack 32 and a case 33. The battery stack 32 includes a plurality of single cells (not shown). The unit cells have, for example, square outer shapes, and are arranged in a line in the left-right direction in FIG. 1 so that a pair of flat surfaces face each other. The cells are electrically connected to each other in series by a bus bar. The unit cells are integrally held by a restraining band or the like. However, the shape, number, arrangement, etc. of the cells may be changed as appropriate. The cell is typically a chargeable / dischargeable secondary battery, such as a lithium ion secondary battery. The unit cell typically includes a positive electrode, a negative electrode, an electrolytic solution, and a unit cell case that houses these. The electrolytic solution includes, for example, a nonaqueous solvent such as carbonates and a supporting salt such as a lithium salt. The unit cell may be an all-solid battery (for example, an all-solid lithium secondary battery), a fuel cell, a nickel metal hydride battery, or another secondary battery. Control of charging / discharging of the unit cell is performed by the control device 60.

  The case 33 is a housing that houses the battery stack 32. The material of the case 33 is, for example, metal or resin. The shape and size of the case 33 may be appropriately changed according to the size and number of the battery stack 32, for example.

  The airbag 40 is provided in the battery pack 30. In the present embodiment, the airbag 40 is provided on the lower surface of the battery pack 30. The airbag 40 may be provided on the upper surface or side surface of the battery pack 30. The airbag 40 is configured to be deployable. The airbag 40 is connected to a gas suction device (not shown) that sucks gas into the airbag 40. As shown in FIG. 3B, when gas is sucked into the airbag 40 from the gas suction device, the airbag 40 is deployed and covers the battery pack 30. The airbag 40 covers, for example, the lower surface and side surfaces of the battery pack 30. That is, the airbag 40 has a function of protecting the battery pack 30. The airbag 40 is controlled by the control device 60. That is, the control device 60 controls the deployment of the airbag 40 by controlling the gas suction device. In the present embodiment, since the airbag 40 is provided outside the passenger compartment, a protective member that protects the airbag 40 from mud, stone, or the like may be provided on the surface of the airbag 40.

  The fixing member 50 is configured to detachably fix the battery pack 30 to the vehicle body 20. As shown in FIG. 3A, in this embodiment, the fixing member 50 includes a first fixing member 51 that fixes the front side of the battery pack 30 and a second fixing member 52 that fixes the rear side of the battery pack 30. ing. The first fixing member 51 and the second fixing member 52 are provided on the floor panel 22. The first fixing member 51 and the second fixing member 52 are, for example, solenoids, and include a plunger 54 and a case body 55 having a coil (not shown) inside. The plunger 54 is configured to be engageable with an engagement hole (not shown) formed in the battery pack 30. Normally, the plunger 54 is engaged with the engagement hole, so that the battery pack 30 is fixed to the vehicle body 20. On the other hand, as shown in FIG. 3C, when the power sources of the first fixing member 51 and the second fixing member 52 are turned on, the plunger 54 moves in a direction away from the battery pack 30. That is, at least a part of the plunger 54 is drawn into the case main body 55. Thereby, the engagement between the plunger 54 and the engagement hole formed in the battery pack 30 is released, and the battery pack 30 is detached from the vehicle body 20. That is, the battery pack 30 falls from the vehicle body 20 together with the airbag 40 as shown by the arrow X in FIG. 3C. The first fixing member 51 and the second fixing member 52 are controlled by the control device 60. That is, the control device 60 controls the power ON and OFF of the first fixing member 51 and the second fixing member 52. The fixing member 50 is not limited to a solenoid. Examples of the fixing member 50 include an electrically controllable mechanism such as an electromagnetic lock mechanism.

  As shown in FIG. 2, the electric vehicle 10 includes a front camera 26 and a rear camera 28. Images (moving images) taken by the front camera 26 and the rear camera 28 are always transmitted to the control device 60. The electric vehicle 10 may further include various sensors that can detect a collision with an obstacle. As the sensor, for example, ultrasonic waves, radio waves, laser light, or the like is emitted forward and backward of the electric vehicle 10 and the reflected wave or reflected light is received, so that the sensor is positioned in front of or behind the electric vehicle 10. Examples include those that can detect the distance, size, moving speed, and the like with an obstacle.

  The control device 60 includes a central processing unit (CPU) that executes instructions of the control program, a ROM that stores a program that is executed by the CPU, a RAM that is used as a working area for developing the program, the program and various data And a storage device such as a memory for storing. As shown in FIG. 2, the control device 60 includes a collision estimation unit 62, an airbag control unit 64, a load input estimation unit 66, a determination unit 68, and a fixed member control unit 70. Each of these units is realized by a program. This program can be downloaded through the Internet. Each of these units may be realized by a processor and / or a circuit. The specific control of each unit described above will be described later.

  Next, an operation procedure of the electric vehicle 10 when a collision with an obstacle is estimated will be described. FIG. 4 is a flowchart according to an embodiment. The estimation of the collision with the obstacle is performed when the electric vehicle 10 is driven (that is, when the electric vehicle 10 can travel, including when the vehicle is stopped and when traveling).

  First, in step S10, the collision estimation unit 62 estimates whether the electric vehicle 10 may collide with an obstacle. The collision estimation unit 62 performs image analysis on the images transmitted from the front camera 26 and the rear camera 28. Thereby, the collision estimation unit 62 calculates a distance, a size, a moving speed, and the like with an obstacle positioned in front of or behind the electric vehicle 10. As a result of the image analysis, when it is estimated that the electric vehicle 10 collides with an obstacle, the process proceeds to step S20. On the other hand, as a result of the image analysis, when it is not estimated that the electric vehicle 10 collides with an obstacle, Step S10 is repeatedly executed until the driving of the electric vehicle 10 is finished (that is, until the vehicle stops). Note that a conventionally known method can be adopted as a method of performing image analysis, and thus description thereof is omitted here.

  When the collision between the electric vehicle 10 and the obstacle is estimated by the collision estimation unit 62, the airbag control unit 64 deploys the airbag 40 in step S20. That is, the airbag control unit 64 controls a gas suction device (not shown) to suck gas into the airbag 40 and deploy the airbag 40. Thereby, the battery pack 30 is protected by the airbag 40.

  Next, in step S30, the load input estimation unit 66 performs image analysis on the images transmitted from the front camera 26 and the rear camera 28. For example, the load input estimation unit 66 calculates the moving speed of the obstacle per frame (one frame), and estimates the energy F due to the collision with the obstacle from the assumed weight of the obstacle. Then, the determination unit 68 compares the energy F estimated by the load input estimation unit 66 with the allowable impact load P that the airbag 40 can withstand. If the determination unit 68 determines that the energy F is greater than or equal to the allowable impact load P, the process proceeds to step S40. On the other hand, when the determination unit 68 determines that the energy F is smaller than the allowable impact load P, the impact applied to the battery pack 30 by the airbag 40 can be sufficiently mitigated. It will not be released. The allowable impact load P is calculated by performing a predetermined strength test (for example, a creep pressure test or a repeated compression test) in advance and is stored in the control device 60.

  When the determination unit 68 determines that the energy F is greater than or equal to the allowable impact load P, the fixing member control unit 70 controls the first fixing member 51 and the second fixing member 52 to control the battery pack 30 with respect to the vehicle body 20. Unpin. Thereby, the battery pack 30 is separated from the vehicle body 20. Here, when the battery pack 30 is separated from the vehicle body 20, a space corresponding to the presence of the battery pack 30 is formed inside the vehicle body 20. Since this space functions as a crushable zone, the energy F transmitted to the electric vehicle 10 can be effectively absorbed at the time of collision with an obstacle.

  As described above, according to the electric vehicle 10 according to the present embodiment, the fixing member control unit 70 fixes the battery pack 30 when the energy F due to the collision with the obstacle is estimated to be equal to or greater than the allowable impact load P. Is released, the battery pack 30 is separated from the vehicle body 20. Thereby, the space in which the battery pack 30 is disposed can be effectively used as a crushable zone, and the energy transmitted to the electric vehicle 10 can be effectively absorbed at the time of collision with an obstacle. Further, the airbag control unit 64 protects the battery pack 30 by deploying the airbag 40 when a collision with an obstacle is estimated. Thereby, the energy input into the battery pack 30 can be reduced, and the collapse of the battery pack 30 can be suppressed.

  As mentioned above, although the electric vehicle proposed here was demonstrated variously, unless it mentions especially, embodiment mentioned here does not limit this invention.

  In the embodiment described above, the first fixing member 51 and the second fixing member 52 are disposed on the front side and the rear side of the battery pack 30, but are not limited thereto. The first fixing member 51 and the second fixing member 52 may be arranged on the side of the battery pack 30, that is, on the left side and the right side.

  In the embodiment described above, the battery pack 30 is disposed outside the vehicle compartment, but a part of the battery pack 30 may be disposed in the vehicle interior.

DESCRIPTION OF SYMBOLS 10 Electric vehicle 20 Car body 30 Battery pack 32 Battery stack 33 Case 40 Airbag 50 Fixing member 51 First fixing member 52 Second fixing member 60 Control device 64 Airbag control part 70 Fixing member control part

Claims (1)

The car body,
A battery stack arranged in a predetermined direction in a state where a plurality of chargeable / dischargeable cells are electrically connected; and a case for housing the battery stack; and a battery pack disposed on the vehicle body,
An airbag provided in the battery pack and configured to be deployable;
A fixing member for detachably fixing the battery pack to the vehicle body;
A control device for controlling the airbag and the fixing member,
The controller is
An airbag control unit that deploys the airbag and protects the battery pack when a collision with an obstacle is estimated; and
An electric vehicle comprising: a fixing member control unit that releases the battery pack from the vehicle body by releasing the fixing of the battery pack when the energy due to the collision with the obstacle is estimated to be a predetermined value or more. .

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