Battery protection structure

Abstract

A battery protection structure includes: a battery pack that houses a battery in an interior of a battery case; and a vehicle body that includes a main frame disposed in left and right directions of a vehicle, a floor pan supported to the main frame, and a rear apron connected to a rear end portion of the floor pan and extending upward from the rear end portion, wherein the battery pack is coupled to a space surrounded by the main frame portion. A length in a vertical direction of the rear apron is longer than a length from a joint portion of the rear apron and the floor pan to a position on the battery pack above an upper surface of the main frame and closest to the joint portion.

Description

Technical Field

[0001] This invention relates to battery protection structures. Background Technology

[0002] In vehicles such as hybrid electric vehicles and electric vehicles, a battery pack for supplying power to an electric motor that serves as a drive source is located in the lower part of the trunk behind the rear seats (for example, see Patent Document 1).

[0003] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2018-167640 Summary of the Invention

[0004] The problem that the invention aims to solve In the event of a rear-end collision, the aforementioned vehicles need to protect components such as the batteries and high-voltage units housed within the battery pack.

[0005] Therefore, the object of the present invention is to properly protect the components disposed inside the battery pack.

[0006] Technical solutions for solving technical problems A battery protection structure according to one embodiment of the present invention includes: a battery pack housing batteries inside a battery box; and a vehicle body including a main frame spaced apart in the left-right direction of the vehicle, a floor chassis supported by the main frame, and a rear skirt connected to the rear end of the floor chassis and extending upward from the rear end. The battery pack is connected to the space enclosed by the main frame. The vertical length of the rear skirt is longer than the length from the joint between the rear skirt and the floor chassis to the position on the battery pack above the upper surface of the main frame and closest to the joint.

[0007] Invention Effects According to the present invention, components disposed inside the battery pack can be properly protected. Attached Figure Description

[0008] Figure 1 It is a diagram showing the general structure of a vehicle.

[0009] Figure 2 This is a diagram illustrating an example of a battery pack being installed.

[0010] Figure 3 This is a diagram showing the composition of a battery pack.

[0011] Figure 4 This is a top view of the lower box.

[0012] Figure 5 This is a picture showing the battery and high-voltage unit housed inside the lower box.

[0013] Figure 6 This is a bottom view of the lower part of the box.

[0014] Figure 7 This is an exploded view of the battery cover.

[0015] Figure 8 yes Figure 3 Section VIII-VIII in the diagram.

[0016] Figure 9 yes Figure 3 IX-IX section view.

[0017] Figure 10 It is a diagram showing the structure of the vehicle body.

[0018] Figure 11 This is a diagram showing a vehicle body equipped with a battery pack.

[0019] Figure 12 This is a diagram showing a vehicle body equipped with a battery pack whose cover has been removed.

[0020] Figure 13 This is a diagram showing the positional relationship between the battery pack and the rear apron.

[0021] Figure 14 This diagram shows the positional relationship between the battery pack and the rear apron during a rear-end collision. Detailed Implementation

[0022] <1. Overview of Vehicle Structure> Figure 1 This is a diagram showing the general structure of vehicle 1. (For example...) Figure 1 As shown, vehicle 1 is an electric vehicle or hybrid vehicle that uses an electric generator 2 (denoted as "M / G" in the figure) as its power source. Vehicle 1 includes the electric generator 2, battery pack 3, inverter 4, and power transmission cables 5. Battery pack 3 includes batteries 11 and high-voltage units 12.

[0023] The electric generator 2 is the power source that drives the vehicle 1, such as a three-phase AC motor. The electric generator 2 uses electricity supplied from the battery 11 through the high-voltage unit 12, inverter 4, and power transmission cable 5 to generate driving force, and transmits this driving force to the drive wheels, thereby moving the vehicle 1. It should be noted that when the vehicle 1 is a hybrid vehicle, it may also have an engine as a power source.

[0024] The electric generator 2 can operate regeneratively to generate electricity. The electricity generated by the regenerative operation of the electric generator 2 is supplied to the battery 11 through the inverter 4, the transmission cable 5 and the high-voltage unit 12.

[0025] Inverter 4 converts the DC current supplied by battery 11 into three-phase AC current, which is then supplied to generator 2 via transmission cable 5. Additionally, when generator 2 is in regenerative operation, inverter 4 converts the AC current supplied by generator 2 into DC current, which is then supplied to battery 11 via transmission cable 5.

[0026] Battery 11 is a so-called high-voltage secondary battery that can store electricity for supplying to the electric generator 2. Battery 11 can be charged through the regenerative operation of the electric generator 2. Alternatively, battery 11 can also be charged by power from an external device (not shown).

[0027] The high-voltage unit 12 comprises a junction box and a monitoring unit. The junction box contains electronic components such as relays, fuses, and connectors. The monitoring unit contains electronic components such as sensors for monitoring the status of the battery 11.

[0028] It should be noted that in vehicle 1, the computer (BCU) used to control the operation of battery 11 is set separately from battery pack 3, but BCU may also be included in high voltage unit 12.

[0029] The high-voltage unit 12 is connected to the battery 11 via a cable (not shown). Therefore, a high voltage from the battery 11 is applied to the high-voltage unit 12.

[0030] Figure 2 This diagram illustrates an example of battery pack 3 being installed. (For example...) Figure 2 As shown, vehicle 1 has a trunk 7 located behind the rear seats 6. The trunk 7 can be opened and closed via the rear door 8.

[0031] Below the trunk 7, the battery pack 3 is installed. Above the battery pack 3, there is a trunk panel 9, on which luggage and other items can be placed.

[0032] <2. Battery Pack Composition> Figure 3 This is a diagram showing the composition of battery pack 3. Figure 4 This is a top view of the lower box 14. Figure 5 The diagram shows the lower box 14 containing the battery 11 and the high-voltage unit 12. Figure 6 This is a bottom view of the lower box 14. Figure 7 This is an exploded view of the battery compartment cover 15. Figure 8 yes Figure 3 Section VIII-VIII in the diagram. Figure 9 yes Figure 3 IX-IX section view.

[0033] It should be noted that in the following description, the forward direction of vehicle 1 is referred to as the forward direction, the reverse direction of vehicle 1 is referred to as the rear direction, the direction to the right relative to the forward direction of vehicle 1 is referred to as the right direction, the direction to the left relative to the forward direction of vehicle 1 is referred to as the left direction, vertically upward is referred to as the upward direction, and vertically downward is referred to as the downward direction. In addition, the left and right directions are sometimes referred to as the width direction of vehicle 1 or simply as the width direction.

[0034] like Figure 3 As shown, the battery pack 3 includes a battery case 13. The battery case 13 houses the battery 11 and the high-voltage unit 12. The battery case 13 is composed of a lower box body 14 with an opening at the top forming a concave shape and a battery case cover 15 that blocks the opening of the lower box body 14.

[0035] like Figures 3 to 6 As shown, the lower box 14 includes a front frame 21, a rear frame 22, a left frame 23, a right frame 24, a battery box chassis 25, a center frame 26, a support rod 27, a left front bracket 28, a right front bracket 29, a left side bracket 30, a right side bracket 31, a center base frame 32, a left side base frame 33, a right side base frame 34, a collision energy absorption box 35, a front base frame 36, and a rear base frame 37.

[0036] The front frame 21 extends in the left-right direction. For example... Figure 8 As shown, the front frame 21 is formed with a downward opening and a cross-section orthogonal to the length direction, which is approximately inverted U-shaped. In other words, the cross-section of the front frame 21 is formed in the shape of a hat.

[0037] The front frame 21 has connection holes 38a, 38b, 38c, and 38d for fixing the battery pack 3 to the vehicle body.

[0038] A front bracket 17 is attached to the front side plane of the front frame 21. The front bracket 17 is mounted to extend downward and forward from the front side wall of the front frame 21. Two through holes are formed on the front side of the front bracket 17, and the battery pack 3 is mounted on the vehicle body 100 (reference). Figure 10 When the time is right, it is connected to the front crossbeam 103 through the through hole using connecting parts (such as bolts and nuts).

[0039] The rear frame 22 is located behind the front frame 21 and is arranged side-by-side with the front frame 21 at intervals in the front-rear direction. It should be noted that "side-by-side" does not only mean completely side-by-side, but also includes roughly side-by-side, and the same applies below.

[0040] The rear frame 22 extends in the same left-right direction as the front frame 21, forming a roughly inverted U-shaped (hat-shaped) cross section orthogonal to the length direction.

[0041] The rear frame 22 has connection holes 38e, 38f, 38g, and 38h for fixing the battery pack 3 to the vehicle body.

[0042] The left frame 23 extends along the front-to-back direction. (Example) Figure 9 As shown, the left frame 23 is formed with a downward opening and a cross-section orthogonal to the length direction, which is approximately inverted U-shaped. In other words, the cross-section of the left frame 23 is formed in the shape of a hat.

[0043] A connecting hole 39a is formed on the rear side of the center of the left frame 23 in the front-rear direction. The connecting hole 39a is formed at a position opposite to the connecting hole 45a of the left bracket 45 described later, and the connecting hole 39a and the connecting hole 45a are connected by a connecting part 47a.

[0044] The right frame 24 is located to the right of the left frame 23, and is arranged side by side with the left frame 23 at intervals in the left-right direction. The right frame 24 and the left frame 23 also extend in the front-back direction, and the cross-section is roughly inverted U-shaped (cap-shaped).

[0045] A connecting hole 39b is formed on the rear side of the center of the right frame 24 in the front-rear direction. The connecting hole 39b is formed at a position opposite to the connecting hole 46a of the right bracket 46 described later, and the connecting hole 39b and the connecting hole 46a are connected by a connecting part 48a.

[0046] It should be noted that the connecting parts 47a and 48a are, for example, bolts and nuts.

[0047] The upper end of the left frame 23 is joined to the left end of the front frame 21. The upper end of the right frame 24 is joined to the right end of the front frame 21.

[0048] The lower end of the left frame 23 is joined to the left end of the rear frame 22. The lower end of the right frame 24 is joined to the right end of the rear frame 22.

[0049] Therefore, the front frame 21, rear frame 22, left frame 23, and right frame 24 are collectively formed into a roughly quadrilateral frame shape. In addition, the cross-sections of the front frame 21, rear frame 22, left frame 23, and right frame 24 are formed into a hat shape, thereby improving rigidity.

[0050] Battery box chassis 25 Figure 8 and Figure 9 As shown, a bottom surface 25a is continuously formed by bending a single sheet of material, along with a front sidewall 25b, a rear sidewall 25c, a left sidewall 25d, and a right sidewall 25e surrounding the bottom surface 25a. Furthermore, the battery box base 25 is formed into a concave shape with an opening at the top by means of the bottom surface 25a, the front sidewall 25b, the rear sidewall 25c, the left sidewall 25d, and the right sidewall 25e.

[0051] The bottom part 25a is formed as a roughly rectangular shape that extends horizontally (front-to-back and left-to-right).

[0052] A front sidewall 25b is continuously formed at the upper end of the bottom part 25a. The front sidewall 25b is formed to extend in the vertical and horizontal directions.

[0053] The lower end of the bottom part 25a is continuously formed with a rear sidewall 25c. The rear sidewall 25c is formed to extend in the vertical direction and the horizontal direction.

[0054] A left side wall 25d is continuously formed at the left end of the bottom part 25a. The left side wall 25d is formed to extend in the vertical direction and the front-back direction.

[0055] A right side wall 25e is continuously formed at the right end of the bottom surface 25a. The right side wall 25e is formed to extend in the vertical and horizontal directions and the front-back direction.

[0056] It should be noted that the battery box chassis 25 can also be formed by combining the bottom part 25a, front side wall 25b, rear side wall 25c, left side wall 25d and right side wall 25e, which are composed of different plates, through welding or other means.

[0057] The upper ends of the front sidewall 25b, rear sidewall 25c, left sidewall 25d, and right sidewall 25e are continuously formed with flanges 25f in a manner that extends outwards. That is, the battery box base 25 has flanges 25f formed at its outer edge. The flanges 25f are formed to extend in the horizontal direction (front-back direction and left-right direction).

[0058] The front frame 21, rear frame 22, left frame 23 and right frame 24 are joined from above to flange 25f.

[0059] The center frame 26 is engaged with the upper surface of the bottom part 25a of the battery box base 25 in a manner that is centered in the left-right direction and along the front-back direction. The center frame 26 is as follows... Figure 8 As shown, the rear end abuts against the rear sidewall 25c, and the front end extends to the front side of the center of the bottom surface 25a in the front-rear direction.

[0060] Central frame 26 Figure 9 As shown, the cross-section orthogonal to the length direction is formed into an inverted U-shape (hat shape), thereby improving rigidity.

[0061] The strut 27 engages with the upper surface of the bottom part 25a in a manner that is centered in the left-right direction of the battery box chassis 25 and coincides with the front end of the center frame 26. The front end of the strut 27 abuts against the front sidewall 25b and extends obliquely upward from the rear to the front. The strut 27 is formed into a cap shape by means of an inverted U-shape (cap shape) orthogonal to the length direction, thereby improving rigidity.

[0062] The left front bracket 28 engages with the upper surface of the bottom portion 25a at its left front. The plate of the left front bracket 28 is curved such that its central portion is approximately horizontal above the upper surface of the bottom portion 25a. Furthermore, as... Figure 5 As shown, a high-voltage unit 12 is installed in the center of the left front bracket 28.

[0063] The right front bracket 29 engages with the upper surface of the bottom portion 25a at its right front. The plate of the right front bracket 29 is curved such that its central portion is approximately horizontal above the upper surface of the bottom portion 25a. Furthermore, as... Figure 5 As shown, a high-voltage unit 12 is installed in the center of the right front bracket 29.

[0064] Thus, the high-voltage unit 12 is installed on the left front bracket 28 and the right front bracket 29 respectively. However, the high-voltage unit 12 can also be installed on only one of the left front bracket 28 and the right front bracket 29.

[0065] The left bracket 30 engages with the upper surface of the bottom part 25a at the left rear. The left bracket 30 is configured to extend in the front-rear direction, and the plate is curved such that the central part is approximately horizontal at a position higher than the upper surface of the bottom part 25a.

[0066] The right bracket 31 engages with the rear right side of the upper surface of the bottom part 25a. The right bracket 31 is configured to extend in the front-rear direction, with the sheet metal curved so that the central part is approximately horizontal at a position higher than the upper surface of the battery box chassis 25.

[0067] Moreover, such as Figure 9 As shown, a battery 11 is mounted on the central part of the left bracket 30 and the right bracket 31.

[0068] It should be noted that battery 11 shown in the figure is an example of a stack consisting of two cells.

[0069] Center base frame 32 Figure 6 As shown, the battery box base 25 extends from the center in the left-right direction and along the front-back direction, engaging with the lower surface of the bottom part 25a. The left base frame 33 and the right base frame 34 are respectively arranged side by side on the left and right sides of the central base frame 32, extending along the front-back direction, and engaging with the lower surface of the bottom part 25a.

[0070] The center base frame 32, the left base frame 33, and the right base frame 34 are as follows: Figure 9 As shown, the rigidity is improved by forming a U-shape (inverted hat shape) by using a cross-section orthogonal to the length direction.

[0071] Thus, the lower box 14 enhances the rigidity of the upper part through the front frame 21, rear frame 22, left frame 23, and right frame 24. Similarly, the lower box 14 enhances the rigidity of the lower part through the central frame 26, strut 27, central base frame 32, left base frame 33, and right base frame 34.

[0072] In addition, the lower housing 14 is protected from damage to the battery box chassis 25 by external forces from the left and right directions via the front frame 21 and the rear frame 22. Furthermore, the lower housing 14 is protected from damage to the battery box chassis 25 by external forces from the front and rear directions via the left frame 23, the right frame 24, the center frame 26, the support rod 27, the center base frame 32, the left base frame 33, and the right base frame 34.

[0073] The impact energy-absorbing box 35 is joined from below to the central rear end of the bottom surface 25a in the form of covering the rear ends of the central base frame 32, the left base frame 33 and the right base frame 34.

[0074] Collision energy absorption box 35 Figure 8 As shown, it is composed of two plates 35a and 35b and a partition member 35c. The front end of plate 35a is joined to the rear sidewall 25c near the center in the vertical direction, and extends downward and rearward from the front end to the rear end.

[0075] The front end of the plate 35b joins the rear end of the bottom surface 25a and the central base frame 32, extending upward and backward from the front end to the rear end.

[0076] The partition member 35c has a structure that connects two partitions that separate the plates 35a and 35b in the vertical direction.

[0077] Furthermore, the impact energy absorption box 35 is formed by plates 35a and 35b such that the cross section orthogonal to the left and right directions becomes a closed cross section (approximately quadrilateral), and its interior is reinforced by partition members 35c, thereby increasing its strength.

[0078] Front chassis 36 Figure 8 As shown, it engages with the front flange 25f of the battery box chassis 25 from below. Thus, the front flange 25f is sandwiched in the middle by the front frame 21 and the front base frame 36 in the battery box chassis 25, and the front rigidity of the lower box body 14 is further improved.

[0079] The rear base frame 37 engages with the rear flange 25f of the battery box chassis 25 from below. Thus, the rear flange 25f is sandwiched in the middle by the rear frame 22 and the rear base frame 37 in the battery box chassis 25, further improving the rear rigidity of the lower box body 14.

[0080] like Figure 3 and Figure 7 As shown, the battery box cover 15 is composed of a main cover 41, a left front cover 42, a service plug cover 43, a right front cover 44, a left bracket 45, and a right bracket 46.

[0081] The main cover 41 is composed of a lower cover 51, a central top frame 52, a first cover beam 53, and a second cover beam 54.

[0082] The lower cover 51 is formed by cutting out approximately rectangular shapes from the left and right front sides of a generally rectangular plate. The front-to-back length of the lower cover 51 is formed to the same extent as the distance between the front frame 21 and the rear frame 22 of the lower box body 14, and the left-to-right length is formed to the same extent as the distance between the left frame 23 and the right frame 24 of the lower box body 14.

[0083] A through hole 51a is formed further below the second cover beam 54 of the lower cover 51. A cooling pipe (not shown) is connected to the through hole 51a. The cooling pipe is used to deliver air from the vehicle compartment to the battery box 13, and the air is delivered to the battery box 13 by a fan (not shown).

[0084] A through hole 51b is formed between the first cover beam 53 and the second cover beam 54 of the lower cover 51. An exhaust pipe 16 is connected to the through hole 51b. One end of the exhaust pipe 16 is connected to the through hole 51b, and the other end opens to the outside of the vehicle. The exhaust pipe 16 is configured to exhaust smoke to the outside of the vehicle when the battery 11 emits smoke.

[0085] The central top frame 52 is located at the center of the lower cover 51 in the left-right direction and extends in the front-back direction to engage with the upper surface of the lower cover 51.

[0086] The front-to-back length of the central top frame 52 is formed to the same extent as the lower cover 51.

[0087] Central top frame 52 Figure 8 As shown, it is mounted on the front frame 21 and the rear frame 22.

[0088] The first cover beam 53 engages with the upper surface of the lower cover 51 in a manner that is near the center in the front-rear direction and extends in the left-right direction. The length of the first cover beam 53 in the left-right direction is formed to the same extent as that of the lower cover 51.

[0089] The second cover beam 54 is joined to the upper surface of the lower cover 51 in a manner that is arranged side-by-side with the first cover beam 53 at a distance in the front-rear direction. The second cover beam 54 is located on the rear side of the first cover beam 53.

[0090] The second cover beam 54 is the same as the first cover beam 53, and its length in the left and right directions is formed to the same extent as the lower cover 51.

[0091] First cover beam 53 and second cover beam 54 as follows Figure 9 As shown, it is mounted on the left frame 23 and the right frame 24.

[0092] In addition, the first cover beam 53 and the second cover beam 54 are as follows Figure 8 As shown, it is positioned directly above battery 11.

[0093] The cross sections of the central top frame 52, the first cover beam 53, and the second cover beam 54, which are orthogonal to the length direction, are formed into an approximately inverted U-shape (hat shape), thereby improving rigidity.

[0094] The thickness of the first cover beam 53 and the second cover beam 54 in the vertical direction is greater than that of the central top frame 52. Therefore, the first cover beam 53 and the second cover beam 54 are engaged with the lower cover 51 in a manner that passes over the central top frame 52.

[0095] The left front cover 42 is formed into a roughly rectangular shape from sheet metal by inserting into the upper left notch of the lower cover 51.

[0096] The left front cover 42 has a through hole 42a located opposite the service plug of the high-voltage unit 12 located inside the battery compartment 13. A service plug cover 43 is installed in the through hole 42a in a manner that covers it from above.

[0097] The service plug cover 43 is formed of sheet metal and can be removed and installed relative to the left front cover 42.

[0098] The right front cover 44 is formed into a roughly rectangular shape from sheet metal by being embedded into the upper right notch of the lower cover 51.

[0099] The left front cover 42 and the right front cover 44 are connected to the lower cover 51 and the central top bracket 52 by means of connecting parts (e.g., bolts and nuts). Thus, the battery box cover 15 is generally rectangular.

[0100] Furthermore, the battery box cover 15 is connected to the front frame 21, rear frame 22, left frame 23, and right frame 24 of the lower box body 14 via a connecting part.

[0101] Viewed from above, the left bracket 45 and the right bracket 46 are formed into a roughly triangular shape from the sheet metal. The left bracket 45 has connecting holes 45a, 45b, and 45c at positions corresponding to the corners of the roughly triangular shape. The right bracket 46 has connecting holes 46a, 46b, and 46c at positions corresponding to the corners of the roughly triangular shape.

[0102] The main cover 41 has a connecting hole 41a at a position opposite to the connecting hole 45b, and a connecting hole 41b at a position opposite to the connecting hole 46b.

[0103] Furthermore, the connecting hole 45a of the left bracket 45 is connected to the connecting hole 39a of the left bracket 23 via the connecting part 47a, and the connecting hole 45b is connected to the connecting hole 41a of the main cover 41 via the connecting part 47b. Thus, the left bracket 45 is fixed to the left bracket 23 and the main cover 41.

[0104] The connecting hole 46a of the right bracket 46 is connected to the connecting hole 39b of the right bracket 24 via the connecting part 48a, and the connecting hole 46b is connected to the connecting hole 41b of the main cover 41 via the connecting part 48b. Thus, the right bracket 46 is fixed to the right bracket 24 and the main cover 41.

[0105] It should be noted that the left bracket 45 and the right bracket 46 are not mandatory configurations and can be omitted.

[0106] <3. Composition of the vehicle body> The following describes the structure of the vehicle body equipped with battery pack 3. Battery pack 3 is envisioned to be installed in multiple different vehicle bodies. Therefore, an example of a vehicle body equipped with battery pack 3 will be described below.

[0107] Figure 10 This is a diagram showing the composition of the vehicle body 100. Figure 11 This is a diagram showing the vehicle body 100 equipped with battery pack 3. Figure 12 This is a diagram showing a vehicle body 100 equipped with a battery pack 3 with the battery box cover 15 removed.

[0108] like Figure 10 , Figure 11 and Figure 12 As shown, the vehicle body 100 includes a left main frame 101 and a right main frame 102. The left main frame 101 and the right main frame 102 are spaced apart in the left-right direction and extend in the front-back direction.

[0109] A front crossbeam 103 and a rear crossbeam 104 are mounted on the left main frame 101 and the right main frame 102. The front crossbeam 103 and the rear crossbeam 104 are connected to the left main frame 101 and the right main frame 102 in a manner that is spaced apart in the front-rear direction and extends in the left-right direction.

[0110] The front crossbeam 103 is positioned in the longitudinal direction near the boundary between the rear seat 6 and the trunk 7. The rear crossbeam 104 is positioned in the longitudinal direction approximately at the center of the trunk 7.

[0111] The front crossbeam 103 has a hollow, approximately quadrilateral closed section orthogonal to its length, thereby improving rigidity. The rear crossbeam 104 also has a hollow, approximately quadrilateral closed section orthogonal to its length, thereby improving rigidity.

[0112] Additionally, a floor base 105 is mounted on the left main frame 101 and the right main frame 102. The floor base 105 is made of bent material, forming a concave shape with an opening at the top. A flange is formed on the outer edge of the floor base 105, and the left main frame 101, the right main frame 102, and the front crossbeam 103 are joined to the flange. It should be noted that the rear crossbeam 104 is joined to the lower surface of the floor base 105.

[0113] A left corner brace 106 is joined at the joint between the left main frame 101 and the front crossbeam 103, thereby strengthening the joint between the left main frame 101 and the front crossbeam 103. Similarly, a right corner brace 107 is joined at the joint between the right main frame 102 and the front crossbeam 103, thereby strengthening the joint between the right main frame 102 and the front crossbeam 103.

[0114] A suspension support member 108, which abuts against the suspension, is joined to the left main frame 101 in the longitudinal direction, further forward than the rear crossbeam 104. The suspension support member 108 is configured to protrude to the left from the left main frame 101. In addition, the suspension support member 108 is configured to tilt upward as it moves toward the left.

[0115] A suspension support member 109, which abuts against the suspension, is joined to the right main frame 102 in the longitudinal direction, further forward than the rear crossbeam 104. The suspension support member 109 is configured to protrude to the right from the right main frame 102. In addition, the suspension support member 109 is configured to tilt upward as it moves toward the right.

[0116] A rear skirt 110 is attached to the rear end of the floor chassis 105. The rear skirt 110 is configured to extend upward from the floor chassis 105. A striker is installed at the center of the left and right sides of the rear skirt 110, which engages with the rear door 8 to close the trunk 7.

[0117] The rear ends of the left main frame 101 and the right main frame 102 are joined by a rear bumper 111. The rear bumper 111 is configured to extend in the left-right direction, with its two ends joining the left main frame 101 and the right main frame 102 respectively. Most of the rear bumper 111 is spaced apart from the left main frame 101, the right main frame 102, the floor chassis 105 and the rear skirt 110 on the rear side.

[0118] The rear bumper 111 is stronger than other components that make up the vehicle body 100, which can reduce the damage to the vehicle body 100 from rear-end collisions (including offset collisions).

[0119] In the vehicle body 100, the battery pack 3 is connected to the left main frame 101, the right main frame 102, and the front crossbeam 103. It should be noted that when the battery pack 3 is connected to the vehicle body 100, the left bracket 45 and the right bracket 46 are not installed on the battery pack 3 (they have been removed).

[0120] The front crossbeam 103 (left corner brace 106, right corner brace 107) has connecting holes 112a and 112b spaced apart on the left side in the left-right direction, and connecting holes 112c and 112d spaced apart on the right side in the left-right direction.

[0121] The left main frame 101 has connecting holes 112e and 112f spaced apart on its rear side in the front-to-back direction. Additionally, the right main frame 102 has connecting holes 112g and 112h spaced apart on its rear side in the front-to-back direction.

[0122] Connection holes 112a to 112h are positioned at positions corresponding to connection holes 38a to 38h formed on the battery pack 3, respectively.

[0123] Furthermore, connecting holes 112a and 38a are connected by connecting portion 113a. Similarly, connecting holes 112b to 112h and connecting holes 38b to 38h are connected by connecting portions 113b to 113h respectively.

[0124] The connecting parts 113e and 113g are composed of screws and nuts welded in the form of extending upward from the upper surfaces of the left main frame 101 and the right main frame 102. The connecting parts 113a, 113b, 113c, 113d, 113f, and 113h are, for example, composed of bolts and nuts.

[0125] It should be noted that, in the following description without distinguishing between connecting parts 113a to 113h, they will be referred to as connecting parts 113.

[0126] <4. Battery Protection Structure> Figure 13 This is a diagram showing the positional relationship between battery pack 3 and rear skirt 110. Figure 14 This diagram shows the positional relationship between battery pack 3 and rear apron 110 during a rear-end collision. It should be noted that... Figure 13 and Figure 14 The upper surfaces 119 of the left main frame 101 and the right main frame 102 are represented by a single-dot dashed line.

[0127] When vehicle 1 is rear-ended by a vehicle with a higher vehicle height or a large vehicle, the other vehicle's body (underbody) may sometimes impact the left main frame 101 and right main frame 102 of vehicle body 100. At this time, when at least one of battery 11 and high-voltage unit 12 is located above the upper surface 119 of the left main frame 101 and right main frame 102, the battery 11 or high-voltage unit 12 located above may be damaged by the other vehicle body.

[0128] Therefore, in the event of a rear-end collision with a vehicle with a high height or a large vehicle, the rear skirt 110 falls forward and acts as a ramp, causing the other vehicle to move to a position higher than the battery 11 and the high-voltage unit 12, thereby reducing the damage to the battery 11 and the high-voltage unit 12.

[0129] like Figure 13 As shown, battery 11 and high-voltage unit 12 are located above the upper surface 119 of left main frame 101 and right main frame 102.

[0130] The rear end of the floor chassis 105 is joined to a rear skirt 110. Here, the joint between the floor chassis 105 and the rear skirt 110 is referred to as joint 120.

[0131] The rear skirt 110 is configured to extend upward from the joint 120, and its upper end forms a box portion 110a with a closed cross-section that is approximately quadrilateral. The box portion 110a is formed by connecting multiple plates, thereby improving rigidity.

[0132] A striker 121 is installed on the upper part of the box section 110a. The striker 121 is made of metal and is hook-shaped. It engages with the latch of the rear door 8 to close the trunk 7.

[0133] When vehicle 1 rear-ends another vehicle or large vehicle (hereinafter referred to as collision vehicle 300), such as Figure 14 As shown, the rear skirt 110 is pushed forward by the collision vehicle 300, causing it to fall forward (rotate) with the joint 120 as the center of rotation (counterclockwise in the figure).

[0134] At this time, the position of the battery pack 3 and the height of the rear skirt 110 are set so that the box part 110a can contact the rear frame 22 of the battery pack 3.

[0135] Both the rear frame 22 and the box 110a are made to be rigid and high, so even if the box 110a comes into contact with the rear frame 22, the battery pack 3 will not be damaged and the box 110a will touch the rear frame 22.

[0136] In this way, the rear skirt 110 will tilt and fall from the joint 120 toward the rear frame 22.

[0137] Therefore, the collision vehicle 300 will use the rear skirt 110 as a ramp to move upward and forward. As a result, the collision vehicle 300 will hit (jump onto) the top of the battery pack 3, which can reduce the risk of the battery pack 3 being crushed by the collision vehicle 300.

[0138] In addition, the position of the battery pack 3, the height of the rear skirt 110, and the size and position of the impact pin 121 are set so that the impact pin 121 can contact the rear frame 22 when the rear skirt 110 falls forward.

[0139] Therefore, when the rear skirt 110 falls forward, the impact pin 121 contacts the rear frame 22, which can reduce the risk of the impact pin 121 damaging the battery pack 3.

[0140] <5. Variations> It should be noted that the above embodiments are one example of implementing the present invention, and the implementation of the present invention is not limited to the above examples; various modifications can be considered.

[0141] For example, the position of the battery pack 3 and the height of the rear skirt 110 are set such that the box portion 110a can contact the rear frame 22 of the battery pack 3. However, the vertical length of the rear skirt 110 can also be longer than the length from the joint 120 to the position on the battery pack 3 above the upper surface 119 of the left main frame 101 and the right main frame 102 and closest to the joint 120.

[0142] Here, the distance from the joint 120 to the position on the battery pack 3 above the upper surface 119 and closest to the joint 120, namely the rear end 22a of the rear frame 22, is defined as distance R1.

[0143] In addition, the distance from the joint 120 to the farthest point 110b of the box portion 110a on the rear skirt 110, which is the farthest point from the joint 120, is set as distance R2.

[0144] In this case, the components of vehicle 1 can be configured and arranged such that the distance R2 is longer than the distance R1.

[0145] Therefore, when the rear skirt 110 falls forward, the rear skirt 110 can come into contact with the battery pack 3, thus enabling the rear skirt 110 to be used as a ramp so that the collision vehicle 300 can hit it from above.

[0146] <6. Summary> As described above, the battery protection structure of the embodiment includes a battery pack 3 in which the battery 11 is housed inside the battery box 13, and a vehicle body 100. The vehicle body 100 includes a main frame (equivalent to a left main frame 101 and a right main frame 102) spaced apart in the left and right directions of the vehicle 1, a floor chassis 105 supported by the main frame, and a rear skirt 110 connected to the rear end of the floor chassis 105 and extending upward from the rear end. The battery pack 3 is connected in the space enclosed by the main frame.

[0147] The vertical length of the rear skirt 110 (equivalent to distance R2) is longer than the length from the joint 120 between the rear skirt 110 and the floor chassis 105 to the position above the upper surface 119 of the main frame on the battery pack 3 and closest to the joint 120 (equivalent to distance R1).

[0148] When vehicle 1 collides with vehicle 300 from behind, the rear skirt 110 will fall forward around the joint 120 as the center of rotation. At this time, the rear skirt 110 will come into contact with the battery pack 3, thus the rear skirt 110 can be used as a ramp to cause vehicle 300 to hit the top of the battery pack 3.

[0149] In this way, the components located inside the battery pack 3 can be properly protected.

[0150] When the battery pack 3 is connected to the vehicle body 100, at least one of the electronic components (equivalent to the high-voltage unit 12) and the battery 11 housed in the battery box 13 is located above the upper surface 119 of the main frame.

[0151] In this situation, the rear skirt 110 can be used as a ramp to cause the crash vehicle 300 to hit the top of the battery pack 3, thereby reducing the damage to the battery 11 and the high-voltage unit 12.

[0152] The battery box 13 includes a first frame portion (equivalent to the front frame 21 and the rear frame 22) spaced apart in the front-rear direction and extending in the left-right direction of the vehicle 1, and a second frame portion (equivalent to the left frame 23 and the right frame 24) spaced apart in the left-right direction and extending in the front-rear direction of the vehicle 1, the first frame portion and the second frame portion forming a frame shape.

[0153] The first frame includes a front frame 21 positioned at the front and a rear frame 22 positioned at the rear.

[0154] The upper part of the rear skirt 110 is provided with a box part 110a with a closed cross section.

[0155] When the rear skirt 110 falls forward with the joint 120 as the center, the box part 110a contacts the rear frame 22.

[0156] Both the rear frame 22 and the box portion 110a are formed to increase rigidity, so even if the box portion 110a comes into contact with the rear frame 22, the battery pack 3 will not be damaged, and the box portion 110a can be in a state where it touches the rear frame 22.

[0157] The battery box 13 includes a first frame portion (equivalent to the front frame 21 and the rear frame 22) spaced apart in the front-rear direction and extending in the left-right direction of the vehicle 1, and a second frame portion (equivalent to the left frame 23 and the right frame 24) spaced apart in the left-right direction and extending in the front-rear direction of the vehicle 1, the first frame portion and the second frame portion forming a frame shape.

[0158] The first frame includes a front frame 21 positioned at the front and a rear frame 22 positioned at the rear.

[0159] The upper part of the rear skirt 110 is provided with a box part 110a with a closed cross section.

[0160] When the rear skirt 110 falls forward with the joint 120 as the center, the firing pin 121 located on the upper part of the rear skirt 110 comes into contact with the rear frame 22.

[0161] Because of the high rigidity of the rear frame 22, the risk of the impact pin 121 damaging the battery pack 3 can be reduced.

[0162] Symbol Explanation 1 vehicle 3 Battery Pack 11 batteries 12 High Voltage Units 22 rear frame 101 Left Main Frame 102 Right Main Frame 105 Floor Chassis 110 rear skirt board 121 Firing pin.

Claims

1. A battery protection structure, comprising: The battery pack contains batteries inside the battery compartment; as well as, The vehicle body includes a main frame spaced apart in the left-right direction, a floor chassis supported by the main frame, and a rear skirt connected to the rear end of the floor chassis and extending upward from the rear end, wherein the battery pack is connected in the space enclosed by the main frame. The length of the rear skirt in the vertical direction is longer than the length from the joint between the rear skirt and the floor chassis to the position on the upper surface of the battery pack above the main frame and closest to the joint.

2. The battery protection structure according to claim 1, wherein, When the battery pack is connected to the vehicle body, at least one of the electronic components housed in the battery box and the battery is located above the upper surface of the main frame.

3. The battery protection structure according to claim 1 or claim 2, wherein, The battery box includes a first frame portion spaced apart in the longitudinal direction of the vehicle and extending in the lateral direction, and a second frame portion spaced apart in the lateral direction of the vehicle and extending in the longitudinal direction, the first frame portion and the second frame portion forming a frame shape. The first frame includes: a front frame disposed at the front and a rear frame disposed at the rear. The upper part of the rear skirt panel is provided with a box section with a closed cross section. When the rear skirt panel falls forward with the joint as the center, the box part comes into contact with the rear frame.

4. The battery protection structure according to claim 1 or claim 2, wherein, The battery box includes: a first frame portion spaced apart in the longitudinal direction of the vehicle and extending in the lateral direction, and a second frame portion spaced apart in the lateral direction of the vehicle and extending in the longitudinal direction, wherein the first frame portion and the second frame portion form a frame shape. The first frame includes: a front frame disposed at the front and a rear frame disposed at the rear. The upper part of the rear skirt panel is provided with a box section with a closed cross section. When the rear skirt panel falls forward with the joint as the center, the firing pin located on the upper part of the rear skirt panel contacts the rear frame.

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