Battery tray made of one-piece molded fiber-reinforced plastic

Abstract

A battery tray for mounting a battery for driving a vehicle includes: a bottom; a peripheral wall erected on the outer periphery of the bottom; a flange connected to the top of the peripheral wall and extending to the outer side of the peripheral wall; a first inner wall connected to the bottom, the first inner wall having a bending angle between the bottom and the bottom being between 90 degrees and 135 degrees; a second inner wall connected to the bottom, the second inner wall having a bending angle between the bottom and the bottom being between 90 degrees and 135 degrees; and a double-ended bolt base connected to the first inner wall and the second inner wall and disposed above the bottom. The bottom, peripheral wall, flange, first inner wall, second inner wall, and double-ended bolt base are integrally molded from fiber-reinforced plastic containing discontinuous fibers.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 047791, filed July 3, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to a battery tray made of one-piece molded fiber-reinforced plastic. Background Technology

[0004] Because onboard batteries occupy a considerable amount of weight and installation space in electric vehicles, their structure has been the subject of various studies.

[0005] For example, JP-UM-B-7-43950 discloses a battery tray made of fiber-reinforced plastic that includes a locking mechanism for clamping bolts used to mount batteries.

[0006] In JP-A-2013-201112, the casing used to house the battery is made of fiber-reinforced plastic to reduce the weight of the battery tray.

[0007] JP-A-2018-156825 discloses a battery pack that houses multiple batteries and the batteries are connected together and fixed to a battery tray.

[0008] JP-A-2011-124101 discloses a battery box that improves the strength and rigidity of the battery tray through a frame-like frame made of metal.

[0009] Technical issues

[0010] However, according to the battery tray disclosed in JP-UM-B-7-43950, it is difficult to lock the battery using only a locking mechanism set around the battery tray when the battery is large or when multiple batteries are installed.

[0011] Because the battery tray disclosed in JP-A-2013-201112 requires large battery brackets on both sides, the size of the battery tray increases. If such large battery brackets are installed, the width of the vehicle itself needs to be increased in order to install the same amount and number of batteries (and therefore, the design freedom of the vehicle is degraded).

[0012] In the case of the battery tray disclosed in JP-A-2018-156825, cross members, which serve as reinforcing components, are disposed between the batteries and the batteries are fixed thereto. Although the batteries do not move relative to the battery tray, the cross members need to be disposed separately, and the weight of the battery tray increases. Furthermore, the process of installing the cross members as separate components is required, thus complicating the manufacturing process.

[0013] In the case of the battery tray disclosed in JP-A-2011-124101, since it is not reinforced with fiber, a frame made of metal is required to reinforce the battery tray, and therefore the weight of the battery box cannot be reduced.

[0014] Therefore, in view of the problems in the prior art, this disclosure provides a battery tray made of integrally molded fiber-reinforced plastic, which does not require separate cross parts or the like to fix the battery and can easily fix the battery. Summary of the Invention

[0015] A battery tray is provided for mounting a battery for driving a vehicle. The battery tray includes: a bottom; a peripheral wall erected on the outer periphery of the bottom; a flange connected to the top of the peripheral wall and extending to the outer side of the peripheral wall; and a first inner wall connected to the bottom, the first inner wall having a bending angle of 90 degrees or more and 135 degrees or less with respect to the bottom. The battery tray has a second inner wall connected to the bottom, the second inner wall having a bending angle of 90 degrees or more and 135 degrees or less with respect to the bottom. A double-ended bolt base is connected to both the first inner wall and the second inner wall and disposed above the bottom. The bottom, the peripheral wall, the flange, the first inner wall, the second inner wall, and the double-ended bolt base are integrally molded from fiber-reinforced plastic comprising discontinuous fibers. Attached Figure Description

[0016] The invention is described in further detail with reference to the following drawings, which are intended to illustrate certain aspects of the invention but should not be construed as limiting the implementation of the invention.

[0017] Figure 1 This is an exploded perspective view of a battery box using a battery tray according to an embodiment of the present disclosure;

[0018] Figure 2 This is a perspective view of a battery tray provided with an energy absorption component according to an embodiment of the present disclosure;

[0019] Figure 3 This is a perspective view of a battery tray according to an embodiment of the present disclosure;

[0020] Figure 4 This is a cross-sectional view of the battery tray according to an embodiment of the present disclosure (along...). Figure 3 (The cross section taken at line IV-IV at the base of the double-ended bolt);

[0021] Figure 5 This is a cross-sectional view of a battery tray according to an embodiment of the present disclosure;

[0022] Figure 6This is a cross-sectional view of the battery tray according to an embodiment of the present disclosure (along...). Figure 3 (The section cut by line VI-VI at the non-existent double-headed bolt base);

[0023] Figure 7A This is a perspective view of an energy absorption component disposed in a battery tray according to an embodiment of the present disclosure;

[0024] Figure 7B This is a perspective view of an energy absorption component disposed in a battery tray according to an embodiment of the present disclosure;

[0025] Figure 7C This is a perspective view of an energy absorption component disposed in a battery tray according to an embodiment of the present disclosure;

[0026] Figure 8A It is a cap-shaped energy absorption component located in the battery tray when viewed from above in the width direction of the vehicle. Figure 2 A schematic diagram of an instance of reference mark 202;

[0027] Figure 8B It is viewed from an angle above in the width direction of the vehicle. Figure 8A A three-dimensional view of the cap-shaped energy absorption component;

[0028] Figure 8C It is viewed in the width direction of the vehicle. Figure 8A Front view of the cap-shaped energy absorption component;

[0029] Figure 8D It is viewed from above. Figure 8A A top view of the cap-shaped energy-absorbing component;

[0030] Figure 9A This is a schematic diagram of a cap-shaped energy absorption component viewed from above in the width direction of the vehicle;

[0031] Figure 9B It is viewed from an angle above in the width direction of the vehicle. Figure 9A A three-dimensional view of the cap-shaped energy absorption component;

[0032] Figure 9C It is viewed in the width direction of the vehicle. Figure 9A Front view of the cap-shaped energy absorption component;

[0033] Figure 9D It is viewed from above. Figure 9A A top view of the cap-shaped energy-absorbing component; and

[0034] Figure 10 It is viewed from above. Figures 9A-9D The top view of the cap-shaped energy absorption component shown.

[0035] Explanation of reference numerals in the attached figures

[0036] 10 Battery Box

[0037] 20 Battery Tray

[0038] 22. Bottom of the battery tray

[0039] 24' 24' battery tray sidewall

[0040] 26, 26' battery tray end wall

[0041] 28 chambers

[0042] 29. The inner partition wall formed by the first inner wall and the second inner wall

[0043] 30, 30', 201 energy absorption components

[0044] 32 Fasteners (for securing energy absorption components and battery trays)

[0045] 40 Battery Cover

[0046] 50 batteries

[0047] 52 Voltage Line

[0048] 60 Enhanced Framework

[0049] 70 Temperature control system (cooling mechanism)

[0050] Top of 304 internal partition wall

[0051] 401 Battery Tray

[0052] 402 flange

[0053] 403 Bottom

[0054] 404, 301 Zhou Bi

[0055] 405 First Inner Wall

[0056] 406 Second Inner Wall

[0057] 407 Double-ended bolt base

[0058] The upper surface of the 408 double-ended bolt base

[0059] 409 double-ended bolt

[0060] 410 battery

[0061] 411 Battery holder

[0062] 412 Insertion Hole

[0063] 413 The space area surrounded by the first inner wall, the second inner wall, and the double-ended bolt base

[0064] 414 Cooling Mechanism

[0065] The angle formed between the bottom of α and the first inner wall

[0066] The angle formed between the bottom of β and the second inner wall

[0067] h1 Height from bottom to flange

[0068] h2 is the height from the bottom to the upper surface of the double-ended bolt base.

[0069] h3 is the height h1 from the bottom to the flange and h3 is the height from the bottom to the second bottom.

[0070] 601 Second Bottom

[0071] 602 Metal Cap

[0072] The inner corner of the boundary area between the bottom and the peripheral wall of R501

[0073] The outer corner of the boundary area between the bottom and the peripheral wall of R502

[0074] The inner corner of the boundary area between the bottom of R520 and the first inner wall

[0075] The outer corner of the boundary area between the bottom of R521 and the first inner wall

[0076] The inner corner of the boundary area between the bottom and the second inner wall of R530

[0077] The outer corner of the boundary area between the bottom and the second inner wall of R531

[0078] The angle at which the top surface of the γ-cap-shaped energy-absorbing component narrows towards the side where energy absorption begins.

[0079] The end of the top surface of the L1 cap-shaped energy absorption component on the energy absorption initiation side.

[0080] length

[0081] The length of the end of the battery tray side on the top surface of the L2 cap-shaped energy absorption component. Detailed Implementation

[0082] This invention can be used as a battery tray for mounting a battery that provides energy to a vehicle. The battery tray includes: a bottom; a peripheral wall erected on the outer periphery of the bottom; a flange connected to the top of the peripheral wall and extending to the outer side of the peripheral wall; and a first inner wall connected to the bottom, the first inner wall having a bending angle of 90 degrees or more and 135 degrees or less with respect to the bottom. The battery tray has a second inner wall connected to the bottom, the second inner wall having a bending angle of 90 degrees or more and 135 degrees or less with respect to the bottom. A double-ended bolt base is connected to both the first inner wall and the second inner wall and disposed above the bottom. The bottom, the peripheral wall, the flange, the first inner wall, the second inner wall, and the double-ended bolt base are integrally molded from fiber-reinforced plastic containing discontinuous fibers.

[0083] One advantage of this invention is that, since the battery tray is made of one-piece molded fiber-reinforced plastic, double-ended bolts for securing the batteries are already provided when the fiber-reinforced plastic is molded. Therefore, when securing multiple batteries, it is not necessary to separately provide double-ended bolt bases and separators.

[0084] It should be understood that when a range of values ​​is set, the range includes not only the endpoint values ​​of the range, but also the intermediate values ​​of the range that are explicitly included in the range and vary through the last significant digit of the range. For example, mentioning a range from 1 to 4 is intended to include 1-2, 1-3, 2-4, 3-4, and 1-4.

[0085] Unless otherwise specified, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0086] Unless otherwise expressly stated or indicated by context, the following terms are used herein as described below.

[0087] As used in the description of the invention and the appended claims, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0088] Embodiments of this disclosure will now be described. However, this disclosure is not limited thereto.

[0089] Battery tray

[0090] like Figure 1 As shown, the battery box includes a battery tray 20 and a battery cover 40. The battery box houses a battery 50 used to power and drive the vehicle. In this disclosure, the battery tray 20 is made of fiber-reinforced plastic comprising reinforcing fibers and resin.

[0091] like Figure 4 As shown, the battery tray 401 according to this disclosure includes a flange 402, a bottom 403, a peripheral wall 404 erected on the outer periphery of the bottom 403, a first inner wall 405 connected to the bottom 403, a second inner wall 406 connected to the bottom 403, and a double-ended bolt base 407 connected to both the first inner wall 405 and the second inner wall 406. The double-ended bolt base 407 rises from the bottom 403.

[0092] bottom

[0093] like Figure 4 As shown, the bottom 403 has a lower surface, which is the lowest surface of the battery tray 401. The battery 50 can be placed on the upper surface of the bottom 403. The battery 50 can be spaced apart from the bottom 403 to provide a cooling mechanism between the battery 50 and the bottom 403. Figure 1 Reference mark 70 and Figure 4 (Referencing reference 414). The bottom 403 does not need to be a complete flat plate and may have a corrugated or curved shape.

[0094] Zhou Bi

[0095] like Figure 3 and Figure 4 As shown, the peripheral wall 404 stands upright on the outer periphery of the bottom 403. Preferably, the peripheral wall 404 and the bottom 403 are formed continuously.

[0096] flange

[0097] like Figure 4 As shown, flange 402 is attached to the top of peripheral wall 404 and extends to the outside of peripheral wall 404. Flange 402 of battery tray 401 is used when fastening battery tray 401 to battery tray using bolts or adhesive.

[0098] First inner wall and second inner wall

[0099] Figure 4 The first inner wall 405 shown is connected to the bottom 403. The bottom 403 and the first inner wall 405 are integrally and seamlessly formed. The inner surface of the bottom 403 is continuously connected to the surface of the first inner wall 405. The battery tray 401 is bent at the connection between the bottom 403 and the first inner wall 405.

[0100] Similarly, Figure 4 The second inner wall 406 shown is connected to the bottom 403. The bottom 403 and the second inner wall 405 are integrally and seamlessly formed. The inner surface of the bottom 403 is continuously connected to the surface of the second inner wall 406. The battery tray 401 is bent at the connection between the bottom 403 and the second inner wall 406.

[0101] Preferably, the first inner wall 405 is connected to the bottom 403 in a state of intersecting with the bottom 403. Similarly, preferably, the second inner wall 406 is connected to the bottom 403 in a state of intersecting with the bottom 403. Here, "intersecting" means that a two-dimensional cross-section of the battery tray 401 shows the state in which the bottom 403 intersects with the first inner wall 405 and the second inner wall 406.

[0102] Internal partition wall

[0103] like Figure 1 As shown, the first inner wall 405 and the second inner wall 406 form an inner partition wall 29, which divides the interior of the battery tray 401. There may be two or more inner partition walls 29. Figure 3 In this configuration, four inner partition walls extend along the Y-axis. Preferably, Figure 3 The X-axis direction is the axle direction (vehicle travel direction), and the Y-axis direction is the vehicle width direction.

[0104] Double-ended bolt base

[0105] Figure 4 The double-ended bolt base 407 shown is connected to both the first inner wall 405 and the second inner wall 406, and the bottom of the double-ended bolt base 407 is located above the bottom 403. That is, the first inner wall 405 and the second inner wall 406 are connected to each other by the double-ended bolt base 407.

[0106] One-piece molding

[0107] Flange 402, bottom 403, peripheral wall 404, first inner wall 405, second inner wall 406, and double-ended bolt base 407 are integrally molded from fiber-reinforced plastic. Here, integral molding refers to the continuous and seamless molding of these components. The integrally molded fiber-reinforced plastic is not formed by connecting individual components to each other. This integral molding enables the manufacture of a single piece of fiber-reinforced plastic through a one-time molding process, and can preferably be achieved through compression molding. Integral fiber-reinforced plastic can also be manufactured by integral molding using sheet molding compound (also known as SMC).

[0108] This one-piece manufacturing process allows separate components to be processed as single parts, thus reducing the unit price of the components. Furthermore, it reduces the number of assembly processes, and the reduced number of components lowers inventory-related costs. Specifically, in this disclosure, the double-ended bolt base 407 for securing the battery 50 can be one-piece molded.

[0109] angle

[0110] The angle formed between the bottom 403 and the first inner wall 405 is Figure 4 The middle part is identified by reference mark α. The angle formed between the bottom 403 and the second inner wall 406 is... Figure 4 It is identified by β.

[0111] The angle α formed between the bottom 403 and the first inner wall 405, and the angle β formed between the bottom 403 and the second inner wall 406, are both greater than 90 degrees and less than 135 degrees. If these angles α and β are less than 90 degrees, it is difficult to remove the molded battery tray 401 from the mold after molding. Conversely, if these angles α and β are greater than 135 degrees, it becomes difficult to match the shape of the battery 410, which may have, for example, a cuboid or cubic shape. In other words, within the aforementioned angle range, it is possible to increase the size of the battery 50 per unit area of ​​the battery tray 401.

[0112] The angle α formed between the bottom 403 and the first inner wall 405 and the angle β formed between the bottom 403 and the second inner wall 406 are preferably 90 degrees or more and 120 degrees or less, and more preferably 90 degrees or more and 100 degrees or less.

[0113] To measure the angle α formed between the bottom 403 and the first inner wall 405, and the angle β formed between the bottom 403 and the second inner wall 406, a cross-section of the battery tray 401 can be observed. Preferably, the cross-section is observed in a direction perpendicular to the bottom 403 and the first inner wall 405, or perpendicular to the bottom 403 and the second inner wall 406. The cross-section to be observed could be, for example, a... Figure 4 .

[0114] If the bottom 403, the first inner wall 405, or the second inner wall 406 has a curved shape in the cross section, the angle is measured by drawing the tangent to the curve, and the maximum and minimum angles among the measured angles are averaged to calculate angle α or angle β.

[0115] Double-ended bolts and double-ended bolt bases

[0116] like Figure 4 As shown, preferably, the battery tray 401 according to this disclosure is provided with a double-ended bolt 409 for mounting the battery holder 411 to the double-ended bolt base 407. Furthermore, the double-ended bolt base 407 may include a non-through insertion hole 412, and the double-ended bolt 409 can be inserted into the insertion hole 412.

[0117] The stud bolt 409 is a bolt with threads at both ends, and one end of the stud bolt 409 is screwed into the insertion hole 412 of the stud bolt base 407. The battery holder 411 for fixing the battery is fastened to the other end of the stud bolt.

[0118] The shape of the double-ended bolt 409 is not particularly limited.

[0119] Through holes for fixing the battery tray

[0120] In the case of a conventional battery tray, in order to fix the battery to the battery tray, through holes for fixing the battery tray in the battery tray need to be provided.

[0121] In the present disclosure, since the flange 402, the bottom 403, the peripheral wall 404, the first inner wall 405, the second inner wall 406, and the stud base 407 are integrally formed of fiber-reinforced plastic, the through holes for fixing the battery tray can be omitted from the first inner wall 405, the second inner wall 406, the bottom 403, and the stud base 407. Since such through holes are not provided, the sealing performance of the battery case 20 is improved, the humidity inside the battery case 10 is stabilized, and the battery life is extended.

[0122] It is also preferable that the peripheral wall 404 does not include through holes for fixing the battery tray.

[0123] Height of the stud base

[0124] Preferably, the height H1 from the bottom 403 to the flange 402 and the height H2 from the bottom 403 to the upper surface of the stud base 407 satisfy the relationship of H1*0.3 < H2 < H1*2.0.

[0125] Since the bottom 403 has a certain thickness, the height H1 is measured based on the center of the bottom 403 in the vertical direction. If the bottom has a corrugated shape or a curved shape, the maximum height is measured as the heights Hl and H2.

[0126] In Figure 4 the heights H1 and H2 are illustrated.

[0127] If the relationship of Hl*0.3 < H2 is satisfied, since the position of the stud base 407 is sufficiently high from the bottom 403, the position of the stud 409 can be set sufficiently high to mount the battery tray 411 on the stud base 407. Therefore, the fixing position of the battery tray 411 for fixing the battery is set higher, and the height of the battery tray 411 can be reduced. Since the battery tray 411 is usually made of a metal such as aluminum, this lower height helps to reduce the weight.

[0128] The lower limit of the height H2 is preferably greater than H1*0.5, more preferably greater than H1*0.6, and further preferably greater than H1*0.7. That is, the heights H1 and H2 preferably satisfy the relationship of H1*0.5 < H2, more preferably satisfy the relationship of H1*0.6 < H2, and further preferably satisfy the relationship of H1*0.7 < H2.

[0129] The upper limit value of the height H2 is preferably less than H1 * 1.8, more preferably less than H1 * 1.5, further preferably less than H1 * 1.2, and most preferably less than H1 * 1.0. That is, the heights H1 and H2 preferably satisfy the relationship H2 < H1 * 1.8, more preferably satisfy the relationship H2 < H1 * 1.5, further preferably satisfy the relationship H2 < H1 * 1.2, and most preferably satisfy the relationship H2 < H1 * 1.0.

[0130] If the relationship H1 * 0.3 < H2 < H1 * 2.0 is satisfied, then as Figure 4 shown, the space region 413 surrounded by the first inner wall 405, the second inner wall 406, and the double-headed bolt base 407 becomes larger.

[0131] Another aspect of the present disclosure

[0132] According to another aspect of the present disclosure, a battery tray 401 according to the following aspects can be adopted, wherein the structure in which the angles α and β are 90 degrees or more and 135 degrees or less as described above is omitted.

[0133] That is, another aspect of the present disclosure provides a battery tray for mounting a battery for driving a vehicle, including:

[0134] A bottom;

[0135] A peripheral wall erected on the outer periphery of the bottom;

[0136] A flange connected to the top of the peripheral wall and extending to the outside of the peripheral wall;

[0137] A first inner wall connected to the bottom, and the connecting portion between the first inner wall and the bottom is bent; and

[0138] A second inner wall connected to the bottom, and the connecting portion between the second inner wall and the bottom is bent; and

[0139] A double-headed bolt base connected to both the first inner wall and the second inner wall and provided above the bottom,

[0140] The bottom, the peripheral wall, the flange, the first inner wall, the second inner wall, and the double-headed bolt base are integrally formed of a fiber-reinforced plastic containing discontinuous fibers,

[0141] The height H1 from the bottom to the flange and the height H2 from the bottom to the upper surface of the double-headed bolt base satisfy the relationship H1 * 0.3 < H2 < H1 * 2.0.

[0142] Ribs and bosses for fixing the battery

[0143] Preferably, ribs or bosses for fixing the battery are provided on the upper surface of the bottom 403 of the battery tray 401. The upper surface of the bottom 403 is the surface for placing the battery on the battery tray 401. The lower surface is the surface opposite to the upper surface. Preferably, the ribs or bosses not only fix the battery 50, but also fix the wiring and the cooling mechanism 414.

[0144] Here, "fixing" means suppressing the movement of the battery, and does not mean complete anchoring.

[0145] The height Hr of the ribs or bosses and the height Hb of the battery preferably satisfy the relationship Hb * 0.3 < Hr, and more preferably satisfy the relationship Hb * 0.5 < Hr. More specifically, the height Hr is preferably 20 mm to 70 mm, more preferably 30 mm to 60 mm, and further preferably 40 mm to 50 mm. If the height Hr is within the above range, the ribs or bosses also help to improve the hardness of the battery tray 401.

[0146] Preferably, the ribs or bosses for fixing the battery are integrally formed of fiber reinforced plastic. The ribs or bosses integrally formed of fiber reinforced plastic can easily and firmly fix the battery 50 to the battery tray 401.

[0147] The shapes of the first inner wall and the second inner wall

[0148] 1. The mating shape of the battery

[0149] Preferably, at least one of the first inner wall 405 or the second inner wall 406 has a shape that mates with the shape of the battery 50. More preferably, both the first inner wall 405 and the second inner wall 406 have shapes that mate with the shape of the battery 50.

[0150] The "shape that mates with the battery shape" is designed to be a shape in which the first inner wall 405 or the second inner wall 配合电池50形状的形状,并且例如,如果电池形状为立方体或长方体,则第一内壁或第二内壁具有平坦的壁。

[0151] [[ID=2x]]2. Mounting the battery tray to the lower part of the vehicle body

[0152] Preferably, the battery tray 401 according to the present disclosure is mounted to the lower part of the vehicle body of an electric vehicle, and the first inner wall 405 and the second inner wall 406 of the battery tray 401 are provided along at least one of the lateral or longitudinal directions of the vehicle body.

[0153] Here, the lateral direction of the vehicle body is, for example, Figure 1 the Y-axis direction in Figure 1 and is the vehicle width direction. For example, in

[0154] It should be noted that there seems to be an incomplete expression in the translation of line . You may need to check and correct it according to the actual situation.Fiber reinforced plastics

[0155] 1. Reinforcing fibers

[0156] Although the reinforcing fibers used in this disclosure are not particularly limited, preferably, the reinforcing fibers are one or more selected from the group consisting of carbon fibers, glass fibers, aramid fibers, boron fibers, and basalt fibers. More preferably, the reinforcing fibers are glass fibers. When glass fibers are used as reinforcing fibers, the average fiber diameter of the glass fibers is preferably from 1 μm to 50 μm, more preferably from 5 μm to 20 μm. If the average fiber diameter is large, the resin's impregnation of the fibers is improved, and if the average fiber diameter is less than the upper limit, it has excellent moldability and processability.

[0157] 2. Discontinuous fibers

[0158] In this disclosure, the reinforcing fibers comprise discontinuous fibers. Using discontinuous fibers improves moldability and facilitates the fabrication of complex molded parts compared to fiber-reinforced plastics using only continuous fibers.

[0159] 3. Weight-average fiber length of reinforcing fibers

[0160] Preferably, the weight-average fiber length of the reinforcing fiber is 1 mm or more and 100 mm or less. More preferably, the weight-average fiber length of the reinforcing fiber is 1 mm to 70 mm, and even more preferably, 1 mm to 50 mm.

[0161] In recent years, the size of vehicle batteries has increased, with battery boxes having longitudinal and lateral dimensions of 1m×1m, 1.5m×1.5m, etc. If the weight-average fiber length is 1mm or more, the mechanical properties for storing large batteries can be easily ensured even when manufacturing such large battery boxes.

[0162] When fiber-reinforced plastics are manufactured by injection molding, the weight-average fiber length of the reinforcing fibers is typically about 0.1 mm to 0.3 mm. When fiber-reinforced plastics are manufactured by compression molding, the weight-average fiber length of the reinforcing fibers is not limited to the range of 0.1 mm to 0.3 mm. Therefore, it is preferable to manufacture fiber-reinforced plastics by compression molding when the weight-average fiber length of the reinforcing fibers is in the range of 1 mm or more and 100 mm or less.

[0163] Preferably, the weight-average fiber length of the reinforcing fiber is set to less than 100 mm because it has excellent flowability. In this disclosure, discontinuous reinforcing fibers with different fiber lengths can be used together. In other words, the discontinuous fibers used in this disclosure can have a single peak or multiple peaks in the weight-average fiber length distribution.

[0164] 4. Fiber volume fraction

[0165] While the fiber body fraction Vf of the reinforcing fiber is not particularly limited, it is preferably 20% to 70%, more preferably 25% to 60%, and even more preferably 30% to 55%.

[0166] Fiber volume fraction (Vf, unit: volume %) refers to the ratio of the volume of reinforcing fiber to the total volume including not only reinforcing fiber and matrix resin but also other additives.

[0167] 5. Resin

[0168] In this disclosure, the type of resin is not particularly limited, and thermosetting or thermoplastic resins are used. When using thermosetting resins, unsaturated polyester resins, vinyl ester resins, epoxy resins, or phenolic resins are preferred.

[0169] A single type of resin can be used alone, or two or more types of resin can be used in combination.

[0170] 6. Other reagents

[0171] Fiber-reinforced plastics used in this disclosure may include additives such as various fiber fillers made of organic or inorganic fibers or non-fiber fillers such as inorganic fillers, flame retardants, UV stabilizers, stabilizers, release agents, pigments, softeners, plasticizers or surfactants, provided that they do not prejudice the purpose of this disclosure.

[0172] In addition, when using thermosetting resins, thickeners, hardeners, polymerization initiators, or polymerization inhibitors may be included.

[0173] One additive can be used alone, or two or more additives can be used in combination.

[0174] 7. Sheet molding compound

[0175] Preferably, the fiber-reinforced plastic is made of sheet molding compound (also known as SMC) using discontinuous reinforcing fibers. When the battery case 10 is made of fiber-reinforced plastic made of SMC, it is possible to reduce weight compared to a battery case made of metal.

[0176] Due to the high moldability of sheet molding compounds, complex shapes such as battery trays or battery covers can be easily formed from SMC.

[0177] That is, fiber-reinforced plastics can be manufactured by molding sheet molding compounds to produce components for battery cases with recesses and protrusions. Because sheet molding compounds have superior flowability and moldability compared to fiber-reinforced plastics containing continuous fibers, ribs and bosses can be easily manufactured.

[0178] As a fiber-reinforced plastic that uses sheet molding compound (SMC), it is possible to use sheet molding compounds manufactured by Continental Structural Plastics (also known as CSP).

[0179] Comparison with JP-A-2011-124101

[0180] The battery tray made of thin-walled resin disclosed in JP-A-2011-124101 is manufactured by injection molding, and the partition wall is a rib protruding from the bottom of the battery tray. If the resin in JP-A-2011-124101 contains fibers, it is difficult to inject reinforcing fibers with a weight-average fiber length of 1 mm or more and 100 mm or less into the ends of the ribs. Even in the case of compression molding instead of injection molding, since the partition wall containing fibers protrudes from the bottom, the ends of the ribs contain more resin than the bottom ends of the ribs, and if the ribs of the partition wall are designed to be high, their physical properties will deteriorate.

[0181] Dispersion of discontinuous fibers in the boundary region

[0182] In this disclosure, preferably, discontinuous fibers are continuously dispersed in the boundary region between the bottom and the first inner wall, the boundary region between the bottom and the second inner wall, and the boundary region between the bottom and the peripheral wall.

[0183] Because the bottom, peripheral walls, first inner wall, and second inner wall are integrally molded fiber-reinforced plastic, discontinuous fibers can be easily and continuously dispersed in the boundary region.

[0184] Here, the term "continuously dispersed" refers to a state in which discontinuous fibers are continuously entangled with each other. For the reinforcing fibers to be continuously dispersed in the boundary region, it is sufficient that the reinforcing fibers are continuously entangled with each other at least in a portion of the boundary region; the reinforcing fibers do not need to be continuously entangled with each other throughout the entire boundary region. If the reinforcing fibers are continuously dispersed in the in-plane direction in the boundary region, the mechanical properties of the boundary region are improved compared to the prior art.

[0185] In the prior art, when the first and second inner walls (used to form the inner partition wall, so-called baffle) are installed as separate components, they need to be fastened to the bottom. However, when the inner partition wall is installed as a separate component, the fastening force between the inner partition wall and the bottom inevitably decreases, and the fastening force becomes unstable.

[0186] Tabletop

[0187] Figure 3 The first inner wall 405 and the second inner wall 406 form an inner partition wall 29. In the battery tray 401 according to this disclosure, the first inner wall 405 and the second inner wall 406 are connected by... Figure 4The stud bolt bases 407 therein are connected to each other. In other words, the stud bolt bases 407 are provided at the top of the inner partition wall 29.

[0188] If the inner partition wall 29 does not have to be provided with Figure 4 the insertion holes 412 for the stud bolts 409 therein, the inner partition wall 29 may have a platen 601 as shown in Figure 6 to replace the stud bolt bases 407. In other words, in the battery tray according to the present disclosure, preferably, the first inner wall 405 and the second inner wall 406 can be connected to each other by Figure 6 the platen 601 therein, and the platen 601 is raised from the bottom 403 by the first inner wall 405 and the second inner wall 406. Figure 6 is a cross-sectional view taken along the line VI-VI in Figure 3 wherein there is no stud bolt base 407 at the top of the inner partition wall 29 formed by the first inner wall 405 and the second inner wall 406.

[0189] Here, preferably, Figure 5 the thickness T1 of the stud bolt base 407 shown in Figure 6 and the thickness T2 of the platen 601 shown in Figure 3 satisfy the relationship of T2 < T1. In other words, preferably, for example, in Figure 3 the top of the inner partition wall 29 formed by the first inner wall 405 and the second inner wall 406 (the reference numeral 304 in Figure 3 ) has a non-uniform thickness in the Y-axis direction (vehicle width direction). Preferably, the top 304 of the inner partition wall 29 has a repetitive structure of the stud bolt base 407 and the platen 601. By designing the thickness (also referred to as wall thickness) T2 of the platen 601 to be smaller than the thickness T1 of the stud bolt base 407, the weight of the battery tray 401 can be reduced. The thicknesses T1 and T2 preferably satisfy the relationship of T2 * 0.8 < T1, and more preferably satisfy the relationship of T2 * 0.5 < T1.

[0190] Preferably, the platen 601 is integrally formed with the flange 402, the bottom 403, the peripheral wall 404, the first inner wall 405, the second inner wall 406, and the stud bolt base 407.

[0191] The platen 601 can be covered with a metal cover 602 to increase hardness.

[0192] Platen height

[0193] Preferably, the height H1 of the flange 402 from the bottom 403 and the height H3 of the platen 601 from the bottom 403 satisfy the relationship of H1 * 0.3 < H3 < H1 * 2.0. Figure 6 The heights H1 and H3 are illustrated in

[0194] If the relationship H1*0.3 < H3 is satisfied, the height of the inner partition wall 29 increases, and thus the battery (50) can be stably held. The lower limit of the height H3 is preferably greater than H1*0.5, more preferably greater than H1*0.6, and even more preferably greater than H1*0.7. That is, the heights H1 and H3 preferably satisfy the relationship H1*0.5 < H3, more preferably satisfy the relationship H1*0.6 < H3, and even more preferably satisfy the relationship H1*0.7 < H3.

[0195] The upper limit of height H3 is preferably less than H1*1.8, more preferably less than H1*1.5, further preferably less than H1*1.2, and most preferably less than H1*1.0. That is, heights H1 and H3 preferably satisfy H3

[0196] The height H2 of the upper surface of the double-ended bolt base 407 from the bottom 403 and the height H3 of the platform 601 from the bottom 403 preferably satisfy H2*0.8. <H3

[0197] Average thickness of fiber-reinforced plastics

[0198] In this disclosure, it is preferred that the average thickness (Tave) of the fiber-reinforced plastic is 1.5 mm or more and less than 5 mm. For the purpose of reducing the weight of the battery case 10, a thickness equal to or less than 5 mm is preferred.

[0199] The average thickness of the fiber-reinforced plastic, Tave, is preferably 2 to 5 mm, and more preferably 3 to 5 mm.

[0200] Radius of curvature of inner corner

[0201] The boundary region between the upper surface of the bottom 403 and the inner surface of the peripheral wall 404 preferably has an inner corner with a radius of curvature equal to or greater than 1 mm and equal to or less than 10 mm. More preferably, the radius of curvature is 1 mm or more and 7 mm or less, and even more preferably 2 mm or more and 4 mm or less.

[0202] For example, in Figure 5 The inner corner of the boundary region between the upper surface of the bottom 403 and the inner surface of the peripheral wall 404 is illustrated by reference numeral R501.

[0203] The boundary region between the upper surface of the bottom 403 and the inner surface of the first inner wall 405 preferably has an inner corner with a radius of curvature equal to or greater than 1 mm and equal to or less than 10 mm. For example, in​​ Figure 5 The inner corner portion in the boundary region between the upper surface of the bottom 403 and the inner surface of the first inner wall 405 is illustrated by reference numeral R520. The radius of curvature is more preferably 1 mm or more and 7 mm or less, and even more preferably 2 mm or more and 4 mm or less.

[0204] The boundary region between the upper surface of the bottom 403 and the inner surface of the second inner wall 406 preferably has an inner corner with a radius of curvature equal to or greater than 1 mm and equal to or less than 10 mm. For example, in Figure 5 The inner corner portion in the boundary region between the upper surface of the bottom 403 and the inner surface of the second inner wall 406 is illustrated by reference numeral R530. The radius of curvature is more preferably 1 mm or more and 7 mm or less, and even more preferably 2 mm or more and 4 mm or less.

[0205] Radius of curvature of outer corner

[0206] The boundary region between the lower surface of the bottom 403 and the outer surface of the peripheral wall 404 preferably has an outer corner with a radius of curvature equal to or greater than 2 mm and equal to or less than 11 mm. More preferably, the radius of curvature is 2 mm or more and 8 mm or less, and even more preferably 3 mm or more and 7 mm or less.

[0207] For example, in Figure 5 The outer corner of the boundary region between the lower surface of the bottom 403 and the outer surface of the peripheral wall 404 is illustrated by reference numeral R502.

[0208] The boundary region between the lower surface of the bottom 403 and the outer surface of the first inner wall 405 preferably has an outer corner with a radius of curvature equal to or greater than 2 mm and equal to or less than 11 mm. For example, in Figure 5 The outer corner of the boundary region between the lower surface of the bottom 403 and the outer surface of the first inner wall 405 is illustrated by reference numeral R521. The radius of curvature is more preferably 2 mm or more and 8 mm or less, and even more preferably 3 mm or more and 7 mm or less.

[0209] The boundary region between the lower surface of the bottom 403 and the outer surface of the second inner wall 406 preferably has an outer corner with a radius of curvature equal to or greater than 12 mm and equal to or less than 22 mm. For example, in Figure 5 The outer corner portion of the boundary region between the lower surface of the bottom 403 and the outer surface of the second inner wall 406 is illustrated by reference numeral R531. The radius of curvature is more preferably 2 mm or more and 8 mm or less, and even more preferably 3 mm or more and 7 mm or less.

[0210] The radius of curvature of the outer corner is preferably greater than that of the inner corner.

[0211] Batteries used to power vehicles

[0212] The battery according to this disclosure is a battery for providing power to a vehicle and for driving the vehicle, and preferably a battery for powering and driving an automobile.

[0213] Energy absorption components

[0214] Preferably, the battery trays 20 and 401 according to this disclosure include energy absorption components. Figure 1 and Figure 2 Reference mark 30 in the text.

[0215] As the number of automotive batteries installed increases, the size of battery packs has also increased year by year. In many cases, the length of the battery pack in the width direction of the vehicle is more than 70% of the vehicle's width, and can even be more than 80%. Therefore, when a large battery pack is installed in the lower part of the vehicle, a greater load is input to the battery pack than a conventional load during a collision. Therefore, it is preferable to install an energy absorption structure to absorb the impact energy of the collision to protect the battery.

[0216] Preferably, an energy-absorbing component 30 is provided to absorb impact energy from the lateral side of the vehicle body, and the energy-absorbing component 30 is provided along the outer side of the peripheral wall 404 in the longitudinal direction of the vehicle body. Figure 2 The Y-axis direction in the diagram represents the direction of the vehicle body.

[0217] Preferably, the shape of the energy absorption component 30 is as follows: Figure 2 The repeated cap shape shown. Energy-absorbing components 30 with a cap shape can be manufactured by compression molding.

[0218] In the shape of the energy-absorbing component having a repeating cap shape, it is preferable that the relationship between the length L1 of the end on the energy absorption initiation side of the top surface of the cap and the length L2 of the end on the battery tray side is L2>L1. Lengths L1 and L2 are measured in the axle direction. Figures 9A-9D ).

[0219] In other words, the top surface of the cap-shaped energy-absorbing component is positioned relative to the vehicle width direction ( Figure 2 The angle γ (in the Y-axis direction) narrows towards the side where energy absorption begins, and the angle γ is preferably 3 degrees or more, and more preferably 10 degrees or more. Figures 7A to 7C and Figure 10 The angle γ is illustrated in the example.

[0220] The patent documents and disclosures mentioned in the specification demonstrate the skill of a person skilled in the art to which this invention pertains. These documents and disclosures are incorporated herein by reference to the same extent that each individual document or disclosure is specifically and individually incorporated herein by reference.

[0221] The foregoing description is an illustration of specific embodiments of the present invention, but does not imply limitation thereof. The following claims, including all their equivalents, are intended to define the scope of the invention.

Claims

1. A battery tray for installing a battery that drives a vehicle, the battery tray comprising: A bottom; A peripheral wall that stands on the outer periphery of the bottom; A flange that is connected to the top of the peripheral wall and extends to the outside of the peripheral wall; A first inner wall that is connected to the bottom, and the bending angle between the first inner wall and the bottom is more than 90 degrees and less than 135 degrees; A second inner wall that is connected to the bottom, and the bending angle between the second inner wall and the bottom is more than 90 degrees and less than 135 degrees; A stud base that is connected to both the first inner wall and the second inner wall and is disposed above the bottom; And A platen that is connected to the first inner wall, the second inner wall, and the stud base, Wherein, the platen is higher than the bottom, and the thickness t1 of the stud base and the thickness t2 of the platen satisfy the relationship of t2 < t1, and Wherein, the bottom, the peripheral wall, the flange, the first inner wall, the second inner wall, the platen, and the stud base are integrally formed of a fiber-reinforced plastic containing discontinuous fibers.

2. The battery tray according to claim 1, further comprising ribs or bosses, the ribs or the bosses being located on the upper surface of the bottom to fix the battery.

3. The battery tray according to claim 1, wherein, At least one of the first inner wall or the second inner wall has a shape configured to fit the shape of the battery.

4. The battery tray according to claim 1, wherein, The boundary region between the bottom and the peripheral wall has an inner corner portion with a radius of curvature equal to or greater than 1 mm and equal to or less than 10 mm.

5. The battery tray according to any one of claims 1 to 4, wherein, The discontinuous fibers are continuously dispersed in the boundary region between the bottom and the first inner wall, the boundary region between the bottom and the second inner wall, and the boundary region between the bottom and the peripheral wall.

6. The battery tray according to any one of claims 1 to 4, configured to be installed on the lower part of the body of an electric vehicle, and in, The first inner wall and the second inner wall are arranged along one of the transverse or longitudinal directions of the vehicle body.

7. The battery tray according to claim 1, wherein, The height h1 from the bottom to the flange and the height h2 from the bottom to the upper surface of the stud base satisfy the relationship of h1 * 0.3 < h2 < h1 * 2.

0.

8. The battery tray according to claim 1, wherein, The first inner wall and the second inner wall are connected to each other via the stud base or the platen.

9. The battery tray according to claim 1, wherein, The stud base is provided with studs for installing a battery bracket.

10. The battery tray according to claim 9, wherein, The stud base includes a non-through insertion hole, and the stud is inserted into the insertion hole.

11. The battery tray according to claim 9, wherein, The first inner wall, the peripheral wall, the second inner wall, and the stud base do not include through holes for fixing the battery bracket.

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