Automotive battery case and method for manufacturing the same

Abstract

To utilize an upper cover to secure high battery protection performance.SOLUTION: A battery case 100 for a motor vehicle includes: an upper cover 120 which is a tray shaped press molding item functioning as a lid, has a housing part 121 for housing a battery 10, and includes upper surface protruding parts 123 provided on an upper surface 122 of the housing part 121, extending from a left end to a right end in a vehicle width direction, and protruding upward; an under cover 150 which closes the upper cover 120 from below to house the battery 10: and an upper surface outer lateral reinforcement material 110 disposed on the upper cover 120 and extending from a lert end to a right end of the housing part 121 in the vehicle width direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an automotive battery case and a method for manufacturing the same.

Background Art

[0002] In an automobile equipped with a large-capacity battery like an electric vehicle, the battery is stored in a battery case and arranged below the passenger compartment. In such an automotive battery case, high sealing performance to prevent water ingress from the road surface and high battery protection performance during an automobile collision are required.

[0003] Patent Documents 1 to 3 disclose automotive battery cases that store a battery in a tray-shaped case to ensure high sealing performance and ensure high battery protection performance by the shape of the tray and reinforcing members.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the automotive battery cases of Patent Documents 1 to 3, the battery is stored in a tray-shaped case and closed from above by a substantially flat upper cover. That is, the lid functions merely as a lid and does not contribute significantly to the battery protection performance.

[0006] The present invention aims to ensure high battery protection performance by utilizing an upper cover in an automobile battery case and a method for manufacturing the same. [Means for solving the problem]

[0007] The first aspect of the present invention provides an automobile battery case comprising: an upper cover which is a tray-shaped press-formed product that functions as a lid and has a storage portion for housing a battery, and an upper surface overhang which extends upward in the vehicle width direction from the left end to the right end of the storage portion; an under cover which closes the upper cover from below to house the battery; and an upper surface outer lateral reinforcing member which is positioned on the upper cover and extends in the vehicle width direction from the left end to the right end of the storage portion.

[0008] This configuration allows for a load transmission path in the vehicle width direction through the upper overhang, ensuring high battery protection against impacts in the vehicle width direction with a simple structure. Specifically, by providing the upper overhang, the load-bearing capacity can be improved compared to a simple flat plate, allowing for the transmission of larger loads. Furthermore, since the upper cover, which is a press-formed product made by press-forming a single metal plate, does not have seams like joints, it can prevent water from entering from the outside and ensure high sealing performance.

[0009] The upper cover and the upper outer lateral reinforcing member may be joined to each other.

[0010] With this configuration, the under cover and the upper outer lateral reinforcement can bear the load as a single unit, thus ensuring even higher battery protection against impacts in the vehicle width direction.

[0011] At least one of the upper cover and the upper outer lateral reinforcing member may constitute a floor panel that forms the floor surface of the vehicle interior.

[0012] This configuration eliminates the need for a separate floor panel, reducing the number of parts and making the vehicle lighter.

[0013] The aforementioned automotive battery case may further include an upper inner lateral reinforcing member that extends in the vehicle width direction from the left end to the right end of the housing along the upper protrusion and is disposed within the upper cover so as to be at least partially housed in the upper protrusion.

[0014] With this configuration, the load can also be supported by the lateral reinforcement material on the upper surface, thus ensuring even higher battery protection against impacts in the vehicle width direction.

[0015] The material of the upper cover may be steel with a tensile strength of 590 MPa or more.

[0016] This configuration ensures even greater battery protection through an upper cover made of high-strength steel.

[0017] Only the central portion of the upper cover in the vehicle's longitudinal direction may have a tailored webbed blank structure.

[0018] These configurations allow for increased strength in the central part of the upper cover in the vehicle's longitudinal direction compared to other parts. For example, the tailored webbed blank structure allows for the use of high-strength materials or increased thickness in this central part. This central part is subjected to high loads during a side collision and requires high load-bearing capacity. Therefore, increasing the strength of this central part is effective.

[0019] The battery may be suspended from the upper cover and positioned so as to float above the under cover.

[0020] With this configuration, even when a load is applied to the underbody cover, the load is not directly transmitted from the underbody cover to the battery, thus ensuring even higher battery protection performance.

[0021] The automotive battery case may further include a longitudinal reinforcing member on the lower surface that is disposed under the under cover, extends in the vehicle longitudinal direction, and is joined to the under cover.

[0022] According to this configuration, since the under cover and the longitudinal reinforcing member on the lower surface can receive the load integrally, high battery protection performance against impacts in the vehicle longitudinal direction can be ensured.

[0023] A second aspect of the present invention provides a method for manufacturing an automotive battery case, which includes preparing an upper cover that is a tray-shaped press-molded product functioning as a lid, having a housing portion for housing the battery, and provided with an upper protruding portion extending in the vehicle width direction from the left end to the right end and protruding upward on the upper surface of the housing portion; an under cover for closing the upper cover from below to house the battery; an upper outer horizontal reinforcing member disposed on the upper cover so as to extend in the vehicle width direction from the left end to the right end of the housing portion; a battery mount installed on the under cover for receiving the battery; and a side sill extending in the vehicle longitudinal direction outside the vehicle width direction of the upper cover, attaching the upper portion of the battery to a base material, placing the battery attached to the base material on the battery mount, fastening the under cover and the side sill from below, and fastening the base material, the upper cover, and the upper outer horizontal reinforcing member, thereby suspending the battery from the upper cover and disposing it floating from the battery mount.

[0024] According to this manufacturing method, high battery protection performance can be ensured by using the upper cover as described above. Further, even when a load is applied to the under cover as described above, since the load is not directly transmitted from the under cover to the battery, higher battery protection performance can be ensured.

Advantages of the Invention

[0025] According to the present invention, in an automotive battery case and its mounting method, high battery protection performance can be ensured by using an upper cover.

Brief Description of the Drawings

[0026] [Figure 1] Side view of an automobile. [Figure 2] Perspective view of an automotive battery case according to the first embodiment of the present invention. [Figure 3] Exploded perspective view of the automotive battery case in FIG. 2. [Figure 4] Perspective view showing an upper cover, an outer upper horizontal reinforcing member, and an inner upper horizontal reinforcing member. [Figure 5] Cross-sectional view of the automotive battery case along the V-V line in FIG. 2. [Figure 6] Perspective view of the vehicle body lower structure equipped with the automotive battery case in FIG. 2. [Figure 7] Perspective view of an upper cover in an automotive battery case according to the second embodiment of the present invention.

Modes for Carrying Out the Invention

[0027] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0028] (First Embodiment) Referring to FIG. 1, an automobile 1 drives a motor by power supplied from a battery 10 to run. For example, the automobile 1 can be an electric vehicle such as an electric car or a plug-in hybrid vehicle. The type of the automobile 1 is not particularly limited and can be a passenger car, a truck, a work vehicle, or other mobility. Hereinafter, the case of a normal passenger car type electric vehicle as the automobile 1 will be described as an example.

[0029] Automobile 1 has a motor and high-voltage equipment mounted in the front part 20 of the vehicle body. Furthermore, Automobile 1 has an automobile battery case 100 (hereinafter simply referred to as battery case 100) housing a battery 10, which serves as the power source for the vehicle, mounted on approximately the entire surface below the passenger compartment R in the central part 30 of the vehicle body. In Figure 1, the longitudinal direction of Automobile 1 is indicated by the X direction (arrows indicate forward), and the vertical direction of the vehicle is indicated by the Z direction (arrows indicate upward). The same notation is used in subsequent figures, and from Figure 2 onwards, the vehicle width direction of Automobile 1 is indicated by the Y direction (arrows indicate right).

[0030] Referring to Figures 2-5, the battery case 100 of this embodiment includes an upper outer lateral reinforcing member 110, an upper cover 120, an upper inner lateral reinforcing member 130, a base material 140, an under cover 150, a battery mount 160, a frame 170, a lower vertical reinforcing member 180, and a bottom plate 190. The battery 10 is not shown in Figure 3, but is shown in Figure 5. The battery 10 has a cylindrical shape that is long in the vertical direction of the vehicle and is densely arranged in the front-rear direction and the width direction of the vehicle. In Figure 5, the area enclosed by the dashed circle is shown in an enlarged view.

[0031] The upper cover 120 is a tray-shaped member that functions as a lid, and is formed by press-forming a single metal plate. That is, the upper cover 120 is a press-formed single-piece product that does not have seams such as joints. The upper cover 120 has a housing section 121 for housing the battery 10, and the upper surface 122 of the housing section 121 is provided with an upper surface overhang 123 that extends upward in the vehicle width direction from the left end to the right end. There may be one or more upper surface overhangs 123. A flange section 124 extends horizontally outward from the lower end of the housing section 121.

[0032] The upper cover 120 is made of, for example, steel. Specifically, the material of the upper cover 120 may be steel with a tensile strength of 590 MPa or more. A high-strength steel upper cover 120 ensures high battery protection performance. Alternatively, the material of the upper cover 120 may be other metal materials such as aluminum alloy.

[0033] The upper outer lateral reinforcing member 110 is a member that reinforces the upper cover 120. In this embodiment, the upper outer lateral reinforcing member 110 is a corrugated sheet having a continuous hat shape in a cross section perpendicular to the vehicle width direction. The upper outer lateral reinforcing member 110 is positioned on top of the upper cover 120 (outside the upper cover 120) and extends in the vehicle width direction from the left end to the right end of the housing portion 121 of the upper cover 120. When viewed from the top or bottom direction of the vehicle, the upper outer lateral reinforcing member 110 has a rectangular shape that is approximately the same size as the housing portion 121 of the upper cover 120. However, the shape, size, or number of the upper outer lateral reinforcing members 110 may be arbitrary.

[0034] The upper outer lateral reinforcing member 110 is joined to the upper cover 120, forming multiple outer reinforcing spaces So between it and the upper cover 120 (see Figure 5). That is, when viewed from the vehicle width direction, the upper outer lateral reinforcing member 110, together with the upper cover 120, forms multiple closed cross-sectional shapes that define multiple outer reinforcing spaces So. This improves the load-bearing capacity in the vehicle width direction.

[0035] The upper outer transverse reinforcing member 110 is made of, for example, steel. Specifically, the material of the upper outer transverse reinforcing member 110 may be steel with a tensile strength of 980 to 1470 MPa or higher. Alternatively, the material of the upper outer transverse reinforcing member 110 may be other metallic materials such as aluminum alloy.

[0036] The upper inner lateral reinforcing member 130 is a member that reinforces the upper cover 120. In this embodiment, the upper inner lateral reinforcing member 130 is a corrugated sheet having a continuous hat shape in a cross section perpendicular to the vehicle width direction. The upper inner lateral reinforcing member 130 is positioned below the upper cover 120 (inside the upper cover 120) so as to be at least partially housed in the upper overhang 123, and extends in the vehicle width direction from the left end to the right end of the housing portion 121 along the upper overhang 123 of the upper cover 120. Also, when viewed from the vertical direction of the vehicle, the upper inner lateral reinforcing member 130 has a rectangular shape that is approximately the same size as the housing portion 121 of the upper cover 120. However, the shape, size, or number of the upper outer lateral reinforcing members 110 may be arbitrary.

[0037] The upper inner lateral reinforcing member 130 is joined to the upper cover 120, forming multiple closed inner reinforcing spaces Si between it and the upper cover 120 (see Figure 5). That is, when viewed from the vehicle width direction, the upper inner lateral reinforcing member 130, together with the upper cover 120, forms multiple closed cross-sectional shapes that define multiple inner reinforcing spaces Si. This improves the load-bearing capacity in the vehicle width direction.

[0038] The upper inner transverse reinforcing member 130 is made of, for example, steel. Specifically, the upper inner transverse reinforcing member 130 may be made of steel with a tensile strength of 980 to 1470 MPa or higher. Alternatively, the upper inner transverse reinforcing member 130 may be made of other metallic materials such as aluminum alloy. The upper inner transverse reinforcing member 130 may be omitted if necessary.

[0039] The base material 140 is a member that holds the battery 10 in a suspended manner. In the example shown in Figure 5, multiple cylindrical batteries 10 are arranged to be suspended from the base material 140. The base material 140 is roughly rectangular when viewed from the vertical direction of the vehicle and has a shape complementary to the upper inner lateral reinforcing member 130 when viewed from the vehicle width direction. The base material 140 is joined to the lower surface of the upper inner lateral reinforcing member 130 and is located at the top of the housing section 121 (see Figure 4).

[0040] The under cover 150 houses the battery 10 by closing the upper cover 120 from below (at least partially). In this embodiment, the under cover 150 is generally flat in shape, with both outer sides of the housing section 121 in the vehicle width direction being lowered by one step.

[0041] The under cover 150 is made of, for example, steel. Specifically, the material of the under cover 150 may be steel with a tensile strength of 590 MPa or higher. This ensures high battery protection performance through the under cover 150 made of high-strength steel. Alternatively, the material of the under cover 150 may be other metal materials such as aluminum alloy.

[0042] The battery mount 160 is installed on the under cover 150 (on the top surface) and is a component that temporarily supports the batteries 10 during the manufacturing process of the battery case 100. The battery mount 160 has multiple bottomed cylindrical shapes complementary to the multiple batteries 10, and supports the multiple batteries 10 to fix their horizontal position. In the finished state of the battery case 100, as described above, the multiple batteries 10 are arranged to be suspended from the base material 140 and are therefore not supported by the battery mount 160. The battery mount 160 may be omitted if necessary.

[0043] The frame 170 is positioned on the outer side of the upper cover 120 in the vehicle width direction. In this embodiment, the frame 170 includes side frames 171 and 172 that extend along the entire length of the upper cover 120 in the vehicle longitudinal direction. However, the frame 170 is not limited to this embodiment and may be positioned, for example, around the entire outer circumference of the upper cover 120 when viewed from the vehicle vertical direction.

[0044] The side frames 171 and 172 are formed, for example, by bending steel plates. Specifically, the material of the side frames 171 and 172 may be steel with a tensile strength of 980 to 1470 MPa or higher. Alternatively, these materials may be other metallic materials such as aluminum alloys. Frame 170 may be omitted if necessary.

[0045] The lower vertical reinforcing members 180 are members that reinforce the under cover 150. The lower vertical reinforcing members 180 are positioned below the under cover 150, extending in the longitudinal direction of the vehicle from the front end to the rear end of the housing section 121, and are joined to the under cover 150. In the illustrated example, three lower vertical reinforcing members 180 with a hat-shaped cross-section are provided.

[0046] The lower vertical reinforcing member 180 is made of, for example, steel. Specifically, the material of the lower vertical reinforcing member 180 may be steel with a tensile strength of 980 to 1470 MPa or higher. Alternatively, the material of the lower vertical reinforcing member 180 may be other metallic materials such as aluminum alloy. The lower vertical reinforcing member 180 may be omitted if necessary.

[0047] The bottom plate 190 is a metal plate positioned below the under cover 150 and the lower vertical reinforcement member 180. The bottom plate 190 is a rectangle approximately the same size as the upper cover 120 when viewed from the vertical direction of the vehicle. The bottom plate 190 is joined to the flange portion 124 of the upper cover 120. In this embodiment, the bottom plate 190 is a flat steel plate. For example, the bottom plate 190 is a 1.4 mm thick steel plate. However, the thickness and material of the bottom plate 190 are not particularly limited and can be arbitrary. The bottom plate 190 may be omitted if necessary.

[0048] Referring to Figure 6, the battery case 100 having the above configuration constitutes a part of the underbody structure of the automobile 1, as will be described below.

[0049] Side sills 200 are positioned on both outer sides of the battery case 100 in the vehicle width direction. The side sills 200 extend in the vehicle's longitudinal direction and are components that constitute the outer surface of the automobile 1 in the vehicle width direction. The side sills 200 are constructed by bonding together an inner panel 210 and an outer panel 220, which are metal plates, and by positioning a cushioning member 230 in the space between the inner panel 210 and the outer panel 220. The cushioning member 230 has a plurality of chambers r1 arranged in the vehicle width direction and has the function of cushioning impacts from the side of the automobile 1.

[0050] In this embodiment, the upper outer lateral reinforcing member 110 constitutes a floor panel that forms the floor surface of the vehicle compartment R. That is, the upper outer lateral reinforcing member 110 has the function of reinforcing the upper cover 120 and the function of a floor panel. If the upper outer lateral reinforcing member 110 is not positioned to cover the entire upper surface 122 of the upper cover 120, then at least one of the upper outer lateral reinforcing member 110 and the upper cover 120 constitutes a floor panel.

[0051] Next, the manufacturing method of the battery case 100 of this embodiment will be described.

[0052] First, prepare the aforementioned components (see Figures 3 and 6). Next, attach the top of the battery 10 to the base material 140. Then, place the battery 10, which is attached to the base material 140, onto the battery mount 160. Then, fasten the under cover 150 on which the battery 10 is mounted, the frame 170, and the side sill 200 from below via the battery mount 160 (for example, by bolt and nut fastening). After that, fasten the base material 140, the upper cover 120, the upper outer lateral reinforcement member 110, and the upper inner lateral reinforcement member 130 (for example, by fastening them together with bolts and nuts) to suspend the battery 10 from the upper cover 120 and position it floating above the battery mount 160 (see Figure 5). As mentioned above, the frame 170 and the upper inner lateral reinforcement member 130 may be omitted if necessary.

[0053] The automotive battery case 100 of this embodiment provides the following effects and advantages.

[0054] The upper protrusion 123 of the upper cover 120 provides a load transmission path in the vehicle width direction, ensuring high battery protection performance against impacts in the vehicle width direction with a simple structure. Specifically, by providing the upper protrusion 123, the load capacity can be improved compared to a simple flat plate, allowing for the transmission of larger loads. Furthermore, since the upper cover 120 is a press-formed product made by press-forming a single metal plate, it does not have seams like joints, thus preventing water from entering from the outside and ensuring high sealing performance.

[0055] Furthermore, since the upper cover 120 and the upper outer lateral reinforcing member 110 are joined to each other, the upper cover 120 and the upper outer lateral reinforcing member 110 can together bear the load. Therefore, even higher battery protection performance against impacts in the vehicle width direction can be ensured.

[0056] Furthermore, since at least one of the upper cover 120 and the upper outer lateral reinforcing member 110 functions as a floor panel, there is no need to provide a separate floor panel, which reduces the number of parts and makes the vehicle lighter.

[0057] Furthermore, since the load can also be supported by the upper inner lateral reinforcement member 130, even higher battery protection performance against impacts in the vehicle width direction can be ensured.

[0058] Furthermore, because the battery 10 is positioned so as to be suspended from the under cover 150, even if a load is applied to the under cover 150, the load is not directly transmitted from the under cover 150 to the battery 10, thus ensuring even higher battery protection performance.

[0059] Furthermore, since the under cover 150 and the lower vertical reinforcement member 180 are joined to each other, the under cover 150 and the lower vertical reinforcement member 180 can bear the load as a single unit. Therefore, high battery protection performance against impacts in the front-to-rear direction of the vehicle can be ensured.

[0060] (Second Embodiment) The automotive battery case of the second embodiment shown in Figure 7 differs from that of the first embodiment in the shape of the upper cover 120. Aside from this difference, it is substantially the same as the first embodiment. Therefore, explanations of parts shown in the first embodiment may be omitted. In Figure 7, only the upper cover 120 is shown, with the area enclosed by the dashed circle being shown in an enlarged view.

[0061] In this embodiment, only the central portion 125 of the upper cover 120 in the vehicle's longitudinal direction has a tailored webbed blank structure. The tailored webbed blank structure is formed by overlapping sheet metal in a specific area using press working. In the illustrated example, the central portion 125 is provided in an area from the center of the vehicle's longitudinal direction to about one-quarter of the way there. The central portion 125 in the vehicle's longitudinal direction may be, for example, an area from the center to about halfway there. Here, the area in front of or behind the central portion 125 in the vehicle's longitudinal direction is referred to as the outer portion 126.

[0062] In the illustrated example of the tailored webbed blank structure, another metal plate 127 is superimposed in the central portion 125, making the thickness of the central portion 125 greater than that of the outer portion 126. That is, only the central portion 125 is composed of two metal plates. For example, if the upper cover 120 is made of steel, a steel plate with higher tensile strength may be superimposed and arranged in the central portion 125.

[0063] According to this embodiment, the strength of the central portion 125 of the upper cover 120 in the vehicle's longitudinal direction can be increased compared to other parts. The central portion 125 is a part that is subjected to high loads in a side collision of a vehicle, and therefore requires high load-bearing capacity. For this reason, increasing the strength of the central portion 125 is effective.

[0064] Although specific embodiments and variations of the present invention have been described above, the present invention is not limited to the above embodiments and can be implemented with various modifications within the scope of this invention. For example, a combination of the contents of individual embodiments may be considered as one embodiment of this invention. [Explanation of Symbols]

[0065] 1. Automobile 10 batteries 20 Front of the vehicle 30 Center of the vehicle 100 Battery Cases (Automotive Battery Cases) 110 Top outer horizontal reinforcement 120 Upper Cover 121 Storage Unit 122 Top 123 Top protrusion 124 Flange section 125 Central part 126 Outer part 127 Metal plate 130 Upper inner lateral reinforcement material 140 Base material 150 Undercover 160 Battery Mount 170 frames 171,172 Side Frame 180 Bottom vertical reinforcement material 190 Bottom Plate 200 Side Sill 210 Inner Panel 220 Outer Panel 230 Cushioning material

Claims

1. An upper cover is a tray-shaped press-formed product that functions as a lid, has a storage compartment for housing a battery, and has an upper surface projection that extends upward from the left end to the right end in the vehicle width direction from the top surface of the storage compartment, The upper cover is closed from below to house the battery, and the under cover is provided. An upper outer transverse reinforcing member is positioned on the upper cover and extends in the vehicle width direction from the left end to the right end of the housing section. A car battery case equipped with [feature / feature].

2. The automobile battery case according to claim 1, wherein the upper cover and the upper outer lateral reinforcing member are joined to each other.

3. The automobile battery case according to claim 1 or 2, wherein at least one of the upper cover and the upper outer lateral reinforcing member constitutes a floor panel that forms the floor surface of the vehicle interior.

4. The automotive battery case according to claim 1 or 2, further comprising an upper inner lateral reinforcing member that extends in the vehicle width direction from the left end to the right end of the housing portion along the upper protrusion and is disposed within the upper cover so as to be at least partially housed in the upper protrusion.

5. The automobile battery case according to claim 1 or 2, wherein the material of the upper cover is steel with a tensile strength of 590 MPa or more.

6. The automotive battery case according to claim 1 or 2, wherein only the central portion of the upper cover in the vehicle's front-rear direction has a tailored webbed blank structure.

7. An automobile battery case using the case according to claim 1 or 2, wherein the battery is suspended from the upper cover and positioned so as to float above the under cover.

8. The automobile battery case according to claim 1 or 2, further comprising a lower vertical reinforcing member positioned below the under cover, extending in the front-rear direction of the vehicle, and joined to the under cover.

9. The invention provides an upper cover which is a tray-shaped press-formed product that functions as a lid and has a storage compartment for housing a battery, and has an upper surface overhang that extends upward in the vehicle width direction from the left end to the right end of the storage compartment; an under cover which closes the upper cover from below to house the battery; an upper surface outer lateral reinforcing member which is positioned on the upper cover so as to extend in the vehicle width direction from the left end to the right end of the storage compartment; a battery mount which is installed on the under cover to support the battery; and a side sill which extends in the vehicle front-rear direction on the outside of the upper cover in the vehicle width direction. The upper part of the aforementioned battery is attached to the base material. The battery attached to the substrate is placed on the battery mount, The under cover and the side sill are fastened together from below. By fastening the base material, the upper cover, and the upper outer lateral reinforcing member together, the battery is suspended from the upper cover and positioned above the battery mount. A method for manufacturing an automobile battery case, including the following.

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