Battery pack shell, battery pack and vehicle

Abstract

The utility model provides a battery pack shell, a battery pack and a vehicle, and relates to the technical field of power batteries. The battery pack shell comprises a shell main body; the shell main body comprises a first laying layer, a second laying layer and a third laying layer which are arranged in a laminated manner, and the shell main body is a fiber composite material shell; the fiber extension direction of the first paving layer is along a first direction, the fiber extension direction of the second paving layer is along a second direction, the extension direction of the third paving layer is along a third direction, the third direction is intersected with the first direction and the second direction, the first direction is along the length direction of the battery pack, and the second direction is along the width direction of the battery pack. The weight of the battery pack shell is effectively reduced, and the bending resistance, the impact resistance, the extrusion resistance, the load-bearing performance and the torsional rigidity of the battery pack shell are improved through the arrangement of the laying layers in the three different fiber extension directions.

Description

Technical Field

[0001] The utility model belongs to the technical field of power batteries, and specifically relates to a battery pack shell, a battery pack and a vehicle. Background Art

[0002] With the development trend of low-carbon economy, new energy vehicles are gradually emerging. As the core power supply component of new energy vehicles, the high strength and lightness of the battery pack shell have received special attention. Achieving high strength of the battery pack shell plays an important role in the safety performance of the battery pack.

[0003] The steel battery pack shell is a low-carbon steel stamping shell or a hot-rolled plate roll-welded shell, which has the advantage of high structural strength, but the material density is high, making the shell heavier. When an aluminum alloy shell is used, its density is low and its weight is light, but most aluminum alloy shells are formed by welding, which makes the shell's strength and bending and torsion resistance poor. Utility Model Content

[0004] In view of this, the utility model aims to provide a battery pack shell, a battery pack and a vehicle, which can solve the problem in the traditional technology that the high strength and low density of the battery pack shell cannot be taken into account at the same time.

[0005] In order to solve the above technical problems, the utility model is achieved as follows:

[0006] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0007] A battery pack shell includes a shell body;

[0008] The shell body comprises a first layer, a second layer and a third layer which are stacked, and the shell body is a fiber composite material shell;

[0009] The fibers of the first layer extend in a first direction, the fibers of the second layer extend in a second direction, the fibers of the third layer extend in a third direction, the third direction intersects the first direction and the second direction, the first direction is along a length direction of the battery pack, and the second direction is along a width direction of the battery pack.

[0010] Furthermore, the shell body includes a bottom plate and a flange;

[0011] The flange is arranged around the outer periphery of the base plate. Both the base plate and the flange include a first ply, a second ply and a third ply which are stacked. The ply thickness of the flange is greater than the ply thickness of the base plate.

[0012] Furthermore, the sum of the number of layers of the first layer of the bottom plate and the second layer of the bottom plate is N1, the number of layers of the third layer of the bottom plate is N2, and 0.8≤N1 / N2≤1.2.

[0013] Furthermore, the sum of the number of layers of the first layer of the flange and the second layer of the bottom plate is N3, the number of layers of the third layer of the flange is N4, and N3>N4.

[0014] Furthermore, an angle formed between the third direction and the first direction, and an angle formed between the third direction and the second direction is 45°.

[0015] Furthermore, the shell body also includes at least two fourth layers;

[0016] The fourth ply is a twill fabric ply, and is stacked with the first ply, the second ply, and the third ply. The fourth ply is disposed on two opposite outer surfaces of the shell body.

[0017] Furthermore, the shell body is a carbon fiber composite material shell.

[0018] Further, the fourth ply includes a first fiber line and a second fiber line that are obliquely connected;

[0019] The first fiber line extends in the first direction, and the second fiber line extends in the second direction; or,

[0020] The included angles between the extending direction of the first fiber line and the first direction and the second direction are both 45°, and the extending direction of the second fiber line is orthogonal to the extending direction of the first fiber line.

[0021] Furthermore, the battery pack housing further includes a protective member;

[0022] The protective member is connected to the first surface of the shell body, the second surface of the shell body is used to connect the battery pack, the first surface and the second surface are opposite to each other, and the protective member is an aramid fiber composite material protective member.

[0023] Furthermore, the battery pack housing further includes a fastener;

[0024] The flange is provided with a first mounting hole, the fastener is embedded in the first mounting hole, and the fastener is used to connect the battery pack.

[0025] Furthermore, the battery pack housing further includes a bushing;

[0026] The flange is provided with a second mounting hole, the bushing is embedded in the second mounting hole, and the bushing is penetrated through the first ply, the second ply, the third ply and the fourth ply, and the bushing is used to connect the vehicle body.

[0027] Compared with the prior art, the battery pack housing described in the present invention has the following advantages:

[0028] The battery pack shell body described in the utility model is formed by stacking and laying at least one first layer, at least one second layer and at least one third layer in the thickness direction. The different layers of the shell body are all fiber composite layers, which are a material formed by collectively compounding fibers or fiber fabrics as reinforcements with resins, metals or ceramics, including carbon fiber composites, glass fiber composites, aramid fiber composites or basalt fiber composites. Such materials have the excellent characteristics of low density, high specific strength and high modulus, which effectively reduce the weight of the battery pack shell while improving the strength and impact resistance of the battery pack shell. The fiber extension direction of the first layer is along the length direction of the battery pack, that is, the front and rear direction of the vehicle, which can improve the bending resistance, impact resistance, extrusion resistance and load-bearing performance of the battery pack shell. The fiber extension direction of the first layer is along the width direction of the battery pack, that is, the left and right direction of the vehicle, which can improve the side column collision resistance of the battery pack shell. The fiber extension direction of the third layer intersects with the fiber extension direction of the first layer and the second layer, which can improve the torsional stiffness of the battery pack shell. Therefore, by setting up three layers with different fiber extension directions, the bending resistance, impact resistance, extrusion resistance, load-bearing performance and torsional stiffness of the battery pack shell are improved.

[0029] Another object of the present invention is to provide a battery pack to reduce the density of the battery pack while improving the strength.

[0030] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0031] A battery pack, comprising a battery group and the battery pack housing as described in any one of the above items;

[0032] The battery pack is fixed in the battery pack housing.

[0033] Another object of the present invention is to provide a vehicle so as to achieve lightweighting of the vehicle and improve the safety of the vehicle's electricity use.

[0034] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0035] A vehicle comprises a battery pack as described in any one of the above items.

[0036] Compared with the prior art, the battery pack and the vehicle described in the present invention have the same advantages as the above-mentioned battery pack housing, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0038] Figure 1 It is a schematic diagram of the main structure of the housing provided by the embodiment of the utility model;

[0039] Figure 2 This utility model embodiment Figure 1 Schematic diagram along direction A;

[0040] Figure 3 Schematic diagram of the extension direction of fibers in different layers in the embodiment of the utility model;

[0041] Figure 4 It is a schematic diagram of the battery pack shell structure provided by an embodiment of the utility model.

[0042] Reference numerals:

[0043] 1-shell body, 101-first ply, 102-second ply, 103-third ply, 104-fourth ply, 11-bottom plate, 12-flange, 121-first mounting hole, 122-second mounting hole, 2-protective member, 3-fastener, 4-bushing, X-first direction, Y-second direction. DETAILED DESCRIPTION

[0044] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0045] The battery pack housing, battery pack and vehicle provided by the embodiments of the present utility model will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0046] The utility model embodiment provides a battery pack housing, referring to Figure 1 and Figure 2The battery pack shell includes a shell body 1; the shell body 1 includes a first ply 101, a second ply 102 and a third ply 103 which are stacked, and the shell body 1 is a fiber composite material shell; the fiber extension direction of the first ply 101 is along a first direction, the fiber extension direction of the second ply 102 is along a second direction, and the extension direction of the third ply 103 is along a third direction, the third direction intersects with the first direction and the second direction, the first direction is along the length direction of the battery pack, and the second direction is along the side direction of the battery pack.

[0047] Specifically, if Figure 1 and Figure 2 As shown, the battery pack shell is formed by the upper shell and the lower shell being buckled and connected, and a cavity for accommodating the battery pack is formed between the upper shell and the lower shell. This embodiment is directed to the lower shell structure, including a shell body 1. The shell body 1 includes multiple layers of plies stacked in the thickness direction, and the multiple layers are all fiber composite plies, which are a material formed by collectively compounding fibers or fiber fabrics as reinforcements with resins, metals or ceramics, including but not limited to carbon fiber composite materials, glass fiber composite materials, aramid fiber composite materials, basalt fiber composite materials, asbestos fiber composite materials or boron fiber composite materials. In this embodiment, carbon fiber composite materials are used to lay the shell body 1. Carbon fiber composite materials are formed by a series of heat treatments of organic carbon fibers, and have both the inherent characteristics of carbon materials and the soft and processable properties of textiles. They have the excellent characteristics of low density, high specific strength, high modulus, no creep, corrosion resistance and good electromagnetic shielding performance. Compared with the aluminum alloy battery pack shell, the weight of the battery pack shell in this embodiment can be reduced by 47%, and carbon is reduced in the raw material stage and throughout the life cycle, and power consumption is reduced in the vehicle use stage. In addition, the strength, impact resistance, bending resistance and torsional stiffness of the battery pack shell are improved.

[0048] Specifically, if Figure 2 and Figure 3As shown, the shell body 1 is formed by stacking and laying at least one first ply 101, at least one second ply 102 and at least one third ply 103 in the thickness direction. The number of each ply can be set to one, two or more layers, and each ply is laid alternately to form the shell body 1, that is, there are other plies between any two identical plies. The first ply 101, the second ply 102 and the third ply 103, all the fibers in each of these three plies have the same extension direction, that is, the three plies all use fiber unidirectional tapes, but the fiber extension directions of different plies are different. Exemplarily, this embodiment uses a 0.2 mm unidirectional tape. The fiber extension direction of the first ply 101 is along the length direction X of the battery pack, that is, the front and rear direction of the vehicle, and the fiber extension direction of the second ply 102 is along the width direction Y of the battery pack, that is, the lateral direction of the vehicle. The first layer 101 and the second layer 102 can enhance the load-bearing, compression resistance, collision resistance and bending performance of the battery pack shell, wherein the first layer 101 especially enhances the bending performance of the battery pack shell and the impact resistance in the front and rear directions of the vehicle, and the second layer 102 especially enhances the side column collision resistance of the battery pack shell. The fiber extension direction of the third layer 103 and the first layer 101 and the second layer 102 all have a certain angle. Let the angle between the fiber extension direction of the third layer 103 and the first layer 101 be α, and the value of the angle α can be 20°, 30°, 45° or 60°. In this embodiment, the value of the angle α is 45°, that is, the angle between the fiber extension direction of the third layer 103 and the second layer 102 is also 45°, and the best torsional stiffness can be obtained at this time.

[0049] The different layers of the battery pack shell provided in this embodiment are all fiber composite material layers, which have the excellent characteristics of low density, high specific strength and high modulus, effectively reducing the weight of the battery pack shell while improving the strength and impact resistance of the battery pack shell. And through the arrangement of three layers with different fiber extension directions, the bending resistance, impact resistance, extrusion resistance, load-bearing performance and torsional stiffness of the battery pack shell are improved.

[0050] Further, see Figure 1 The shell body 1 includes a bottom plate 11 and a flange 12; the flange 12 is arranged around the outer periphery of the bottom plate 11, and the bottom plate 11 and the flange 12 both include a first laminate 101, a second laminate 102 and a third laminate 103, and the laminate thickness of the flange 12 is greater than the laminate thickness of the bottom plate 11.

[0051] Specifically, if Figure 1As shown, the shell body 1 includes a bottom plate 11 and a flange 12. The flange 12 is arranged around the periphery of the bottom plate 11, and the height of the flange 12 is higher than the bottom plate 11. The flange 12 is used to install and fix the battery pack and seal the vehicle body, and the bottom plate 11 bears the weight of the battery pack. The surface of the bottom plate 11 is the large surface of the battery pack shell, and the surface of the flange 12 is the sealing surface. The flange 12 and the bottom plate 11 are both formed by plying of fiber composite materials. The ply thickness of the flange 12 is greater than the ply thickness of the bottom plate 11. In this embodiment, the ply thickness of the flange 12 is 14.62 mm, and the ply thickness of the bottom plate 11 is 5.12 mm.

[0052] Furthermore, the sum of the number of layers of the first ply 101 of the bottom plate 11 and the second ply 102 of the bottom plate 11 is N1, the number of layers of the third ply 103 of the bottom plate 11 is N2, and 0.8≤N1 / N2≤1.2.

[0053] Furthermore, the sum of the number of layers of the first layer 101 of the flange 12 and the second layer 102 of the bottom plate 11 is N3, and the number of layers of the third layer 103 of the flange 12 is N4, where N3>N4.

[0054] Specifically, the bottom plate 11 mainly bears the weight of the battery pack, and its torsion resistance is required to be relatively high, while the anti-collision performance and bending performance of the flange 12 are required to be relatively high. Therefore, in order to improve the torsion resistance of the bottom plate 11 and the anti-collision performance and bending performance of the flange 12, the proportion of the number of layers of the third layer 103 in the bottom plate 11 is set to be higher than the proportion of the number of layers of the third layer 103 in the flange 12. The sum of the number of layers of the first layer 101 of the bottom plate 11 and the second layer 102 of the bottom plate 11 is N1, and the number of layers of the third layer 103 of the bottom plate 11 is N2, 0.8≤N1 / N2≤1.2, and this embodiment sets N1 / N2=1. The sum of the number of layers of the first layer 101 of the flange 12 and the second layer 102 of the bottom plate 11 is N3, and the number of layers of the third layer 103 of the flange 12 is N4, N3>N4, and this embodiment sets N3 / N4=8 / 3.

[0055] Further, see Figure 3 The shell body 1 also includes at least two fourth plies 104; the fourth ply 104 is a twill fabric ply, the fourth ply 104 is stacked with the first ply 101, the second ply 102 and the third ply 103, and the fourth ply 104 is provided on two opposite outer surfaces of the shell body 1.

[0056] Specifically, if Figure 3As shown, the shell body 1 is formed by four layers, namely the first layer 101, the second layer 102, the third layer 103 and the fourth layer 104, which are stacked and laid along the thickness direction. Among them, the first layer 101, the second layer 102, and the third layer 103 are unidirectional tapes, and the fourth layer 104 is a twill fabric. In this embodiment, the fourth layer with a thickness of 0.43 mm is selected. In comparison, the mechanical properties of the unidirectional tape include strong tensile strength and bending properties, while the twill fabric has strong surface bonding properties, which can be beneficial for combining different layers to form a tight whole, and the twill fabric has good aesthetics. A layer of the fourth layer 104 is laid on the upper and lower surfaces of the shell body 1, which improves the surface aesthetics while meeting the mechanical properties of the battery pack shell.

[0057] Furthermore, the fourth ply 104 includes a first fiber line and a second fiber line that are obliquely connected; the extension direction of the first fiber line is along the first direction, and the extension direction of the second fiber line is along the second direction; or, the angles between the extension direction of the first fiber line and the first direction and the second direction are both 45°, and the extension direction of the second fiber line is orthogonal to the extension direction of the first fiber line.

[0058] Specifically, the fourth ply 104 is formed by a plurality of first fiber lines, i.e., warps, and a plurality of second fiber lines, i.e., wefts, being interwoven under a certain rule. According to the strength performance test results, when the continuous fibers are perpendicular to each other, i.e., the first fiber line and the second fiber line are cross-woven at 90°, the fiber structure strength is the highest. Exemplarily, in one embodiment, the extension direction of the first fiber line is set along the first direction X, and the extension direction of the second fiber line is set along the second direction Y, i.e., the fiber extension direction of the fourth ply 104 is 0° and 90°, which can improve the load-bearing, compression resistance, collision resistance and bending performance of the fourth ply 104. In another embodiment, the angles between the extension direction of the first fiber line and the first direction X and the second direction Y are all 45°, and the extension direction of the second fiber line is orthogonal to the extension direction of the first fiber line, i.e., the fiber extension direction of the fourth ply 104 is 45° and -45°, which can improve the torsional stiffness of the fourth ply 104. In some embodiments, a first ply 101 of unidirectional tape plies with a fiber direction of 0°, a second ply 102 of unidirectional tape plies with a fiber direction of 90°, a third ply 103 of unidirectional tape plies with a fiber direction of 45°, a third ply 103 of unidirectional tape plies with a fiber direction of -45°, a fourth ply 104 of twill fabric plies with fiber directions of 0° and 90°, and a fourth ply 104 of twill fabric plies with fiber directions of 45° and -45° are selected and laid at the bottom plate 11 and the flange 12, respectively.

[0059] Table 1 Layer distribution table of the bottom plate 11 position

[0060]

[0061]

[0062] Table 2 Distribution of plies at flange 12 position

[0063]

[0064]

[0065]

[0066] According to the distribution law of the fiber plies in Tables 1 and 2 above, two types of materials are used, namely unidirectional tape and twill fabric, wherein all the fiber lines in the unidirectional tape ply extend in the same direction, and a certain angle is formed between different fiber lines in the twill fabric. In order to improve the fiber strength, the same ply is avoided to be set continuously, and the middle ply is taken as the symmetry center, and the plies on both sides are symmetrically set. The ply thickness of the bottom plate 11 is 5.12mm, and the ply thickness of the flange 12 is 14.62mm. In Table 1, the sum of the number of layers of the first ply 101 and the second ply 102 of the bottom plate 11 is N1, and the number of layers of the third ply 103 is N2, and N1 / N2=9 / 8. In Table 2, the sum of the number of layers of the first ply 101 and the second ply 102 of the bottom plate 11 is N3, and the number of layers of the third ply 103 is N4, and N3 / N4=8 / 3.

[0067] Further, see Figure 4 The battery pack shell also includes a protective member 2; the protective member 2 is connected to the first surface of the shell body 1, and the second surface of the shell body 1 is used to connect the battery pack, the first surface and the second surface are opposite to each other, and the protective member 2 is an aramid fiber composite material protective member.

[0068] Specifically, if Figure 4 As shown, the protective member 2 is connected to the first surface of the shell body 1, that is, the lower surface of the shell body 1. The protective member 2 is made of aramid fiber composite material, which has excellent properties of low density, high strength, high modulus, high temperature resistance, corrosion resistance and insulation. The protective member 2 can improve the impact resistance of the lower part of the battery pack shell and the temperature resistance of the battery pack. This embodiment uses aramid fiber composite prepreg with a thickness of 1 mm, which can double the impact resistance of the bottom of the battery pack.

[0069] Further, see Figure 4 The battery pack shell also includes a fastener 3; the flange 12 is provided with a first mounting hole 121, and the fastener 3 is embedded in the first mounting hole 121, and the fastener 3 is used to connect the battery pack.

[0070] Specifically, if Figure 4As shown, the fastener 3 is embedded in the first mounting hole 121 of the flange 12 for connecting the battery pack. The fastener 3 of this embodiment adopts a cross-shaped anti-rotation nut to improve the reliability of the connection between the battery pack and the battery pack housing.

[0071] Further, see Figure 4 The battery pack shell also includes a bushing 4; the flange 12 is provided with a second mounting hole 122, the bushing 4 is embedded in the second mounting hole 122, and the bushing 4 is penetrated through the first ply 101, the second ply 102, the third ply 103 and the fourth ply 104, and the bushing 4 is used to connect the vehicle body.

[0072] Specifically, if Figure 4 As shown, a bushing 4 is installed in the second mounting hole 122 of the flange 12. The bushing 4 passes through each layer to prevent the fiber composite material from being delaminated, so that the anti-torque performance is attenuated. The bushing 4 is also used to connect the vehicle body. In this embodiment, a stainless steel bushing is used to improve the sealing between the battery pack housing and the vehicle body.

[0073] An embodiment of the utility model further provides a battery pack, which includes a battery group and a battery pack shell as described in any one of the aforementioned embodiments, wherein the battery group is fixed in the battery pack shell.

[0074] An embodiment of the utility model also provides a vehicle, comprising the battery pack described in any one of the aforementioned embodiments, and by improving the bending resistance, impact resistance, extrusion resistance and load-bearing performance of the battery pack, the vehicle is lightweighted and the safety of vehicle electricity use is improved.

[0075] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery pack housing, characterized in that: It comprises a housing body (1); The shell body (1) comprises a first ply (101), a second ply (102) and a third ply (103) which are stacked, and the shell body (1) is a fiber composite material shell; The fibers of the first ply (101) extend in a first direction, the fibers of the second ply (102) extend in a second direction, the fibers of the third ply (103) extend in a third direction, the third direction intersects with the first direction and the second direction, the first direction is along the length direction of the battery pack, and the second direction is along the width direction of the battery pack.

2. The battery pack housing according to claim 1, characterized in that: The shell body (1) comprises a bottom plate (11) and a flange (12); The flange (12) is arranged around the outer periphery of the base plate (11); the base plate (11) and the flange (12) both include a first ply (101), a second ply (102) and a third ply (103) which are stacked; and the ply thickness of the flange (12) is greater than the ply thickness of the base plate (11).

3. The battery pack housing according to claim 2, characterized in that: The sum of the number of layers of the first ply (101) of the bottom plate (11) and the second ply (102) of the bottom plate (11) is N1, the number of layers of the third ply (103) of the bottom plate (11) is N2, and 0.8≤N1 / N2≤1.

2.

4. The battery pack housing according to claim 2, characterized in that: The sum of the number of layers of the first layer (101) of the flange (12) and the second layer (102) of the bottom plate (11) is N3, and the number of layers of the third layer (103) of the flange (12) is N4, where N3>N4.

5. The battery pack housing according to claim 1 or 2, characterized in that: An angle formed between the third direction and the first direction, and an angle formed between the third direction and the second direction is 45°.

6. The battery pack casing according to claim 2, characterized in that: The shell body (1) further comprises at least two fourth layers (104); The fourth ply (104) is a twill fabric ply, and the fourth ply (104) is stacked with the first ply (101), the second ply (102) and the third ply (103), and the fourth ply (104) is provided on two opposite outer surfaces of the shell body (1).

7. The battery pack casing according to claim 6, characterized in that: The shell body (1) is a carbon fiber composite material shell.

8. The battery pack casing according to claim 6, characterized in that: The fourth ply (104) includes a first fiber line and a second fiber line connected obliquely; The first fiber line extends in the first direction, and the second fiber line extends in the second direction; or, The included angles between the extending direction of the first fiber line and the first direction and the second direction are both 45°, and the extending direction of the second fiber line is orthogonal to the extending direction of the first fiber line.

9. The battery pack housing according to claim 1 or 2, characterized in that: The battery pack housing further comprises a protective member (2); The protective member (2) is connected to the first surface of the shell body (1); the second surface of the shell body (1) is used to connect the battery pack; the first surface and the second surface are opposite to each other; and the protective member (2) is an aramid fiber composite material protective member.

10. The battery pack housing according to claim 2, characterized in that: The battery pack housing further comprises a fastener (3); The flange (12) is provided with a first mounting hole (121), the fastener (3) is embedded in the first mounting hole (121), and the fastener (3) is used to connect a battery pack.

11. The battery pack housing according to claim 7, characterized in that: The battery pack housing further comprises a bushing (4); The flange (12) is provided with a second mounting hole (122), the bushing (4) is embedded in the second mounting hole (122), and the bushing (4) is penetrated through the first ply (101), the second ply (102), the third ply (103) and the fourth ply (104), and the bushing (4) is used to connect the vehicle body.

12. A battery pack, characterized in that: The battery pack comprises a battery pack and a battery pack housing as claimed in any one of claims 1 to 11; The battery pack is fixed in the battery pack housing.

13. A vehicle, characterized in that: The vehicle includes the battery pack described in claim 12.

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