Battery device

Abstract

The invention provides a battery device. This battery device is provided with: a plurality of unit cells each provided with a unit cell case provided with a relief valve that opens when the internal pressure reaches a prescribed value; a case housing the plurality of unit cells; the non-combustible paper is arranged on at least one part of the inner surface of the shell; the middle piece is arranged on the side, opposite to the inner surface of the shell, of the non-combustible paper and has the mechanical strength higher than that of the non-combustible paper; and an insulating plate that is provided on the surface of the intermediate material on the opposite side from the non-combustible paper, faces the relief valve, and has electrical insulating properties and higher mechanical strength than the non-combustible paper, and the heat insulating properties of the non-combustible paper and the intermediate material are higher than the insulating plate.

Description

Technical Field

[0001] This disclosure relates to battery devices. Background Technology

[0002] Japanese Patent No. 7087648 discloses a battery device in which multiple individual cells are disposed inside a casing. The casing comprises a lower casing made of metal and an upper casing made of resin. An iron plate is fixed to the top of the inner surface of the upper casing, opposite to the release valve disposed on the upper part of each individual cell.

[0003] When the internal pressure of a single cell rises, the release valve opens, and high-temperature gas is rapidly discharged from the release valve to the outside of the single cell, impacting the iron plate. Therefore, the iron plate suppresses the phenomenon of the upper casing becoming hot due to the high-temperature gas discharged from the single cell.

[0004] In Japanese Patent No. 7087648, when the iron plate falls from the upper casing due to the influence of gas, the upper casing may become hot. Thus, Japanese Patent No. 7087648 still has room for improvement in suppressing the phenomenon of the casing becoming hot due to the influence of hot substances emitted from the single cell. Summary of the Invention

[0005] This disclosure takes into account the above facts in order to obtain a battery device capable of suppressing the phenomenon that the casing becomes hot due to the influence of substances discharged from the single cell.

[0006] The battery device of the first method is as follows. That is:

[0007] A battery device comprising:

[0008] Multiple individual cells, each individual cell having a cell housing equipped with a release valve that opens when the internal pressure reaches a specified value;

[0009] A housing that contains multiple of the aforementioned individual batteries;

[0010] Non-combustible paper, which is disposed on at least a portion of the inner surface of the aforementioned housing;

[0011] An intermediate component, disposed on the side of the non-combustible paper opposite to the inner surface, has higher mechanical strength than the non-combustible paper; and

[0012] An insulating plate is disposed on the side of the intermediate component opposite to the non-combustible paper, opposite the release valve, and has electrical insulation properties and higher mechanical strength than the non-combustible paper.

[0013] The heat insulation properties of the aforementioned non-combustible paper and the aforementioned intermediate component are higher than those of the aforementioned insulating board.

[0014] In the battery device of the first type, when the internal pressure of a single cell reaches a predetermined value, the release valve opens, discharging the material inside the single cell to the outside of the single cell casing. Therefore, the high-temperature material sometimes violently impacts the insulating plate opposite the release valve. However, the mechanical strength of the insulating plate and the intermediate piece located between the insulating plate and the non-combustible paper is higher than that of the non-combustible paper. Therefore, even if the material violently impacts the insulating plate, the possibility of the non-combustible paper peeling off from the inner surface of the casing is small. Therefore, the phenomenon of heat transfer from the material to the casing can be suppressed by the non-combustible paper.

[0015] Furthermore, if the insulating plate of the battery device of the first embodiment detaches from the casing, the insulating plate may sometimes come into contact with the terminals of two adjacent individual cells simultaneously. However, since the insulating plate is electrically insulating, a short circuit will not occur between two adjacent individual cells via the insulating plate. Therefore, the possibility of the individual cells becoming hot due to a short circuit is small.

[0016] In this way, when material is discharged from a single cell, the heat of that material is difficult to transfer to the casing, and no short circuit occurs between two adjacent single cells via the insulating plate. Therefore, the battery device of the first embodiment can suppress the phenomenon that the casing becomes hot due to the influence of material discharged from the single cell.

[0017] The second type of battery device is that, in the first type, the casing is made of an iron-containing material, and the inner surface of the casing is coated with a cationic coating.

[0018] Although the casing of the battery device of the second type is made of an iron-containing material, it is difficult for the casing to rust due to the cationic coating applied to its surface. Furthermore, the cationic-coated areas are prone to spontaneous combustion when exposed to high temperatures. However, because the casing is unlikely to reach high temperatures, the likelihood of spontaneous combustion in the cationic-coated areas is low when high-temperature substances are discharged from the single cell.

[0019] The third type of battery device is one in which, in the first or second type, the area of ​​the non-flammable paper and the intermediate component, when viewed in the thickness direction of the non-flammable paper, is larger than the area of ​​the insulating plate.

[0020] In the battery device of the third type, the range of gas discharge from a single cell is wider than the range of gas discharge from a single cell caused by a material violently impacting the insulating plate. However, since the area of ​​the non-flammable paper and the intermediate component is larger than the area of ​​the insulating plate when viewed in the thickness direction of the non-flammable paper, the phenomenon that the casing becomes hot due to the high-temperature gas discharged over a wider range than the material violently impacting the insulating plate can be suppressed by the non-flammable paper and the intermediate component.

[0021] The battery device of the fourth method is, in any of the methods 1 to 3, the aforementioned intermediate component is glass cloth.

[0022] In the fourth type of battery device, the intermediate component is glass cloth. Therefore, it is easy to manufacture the intermediate component at low cost, as it has higher mechanical strength than non-combustible paper and higher thermal insulation than insulating board.

[0023] The battery device of the fifth type is wherein, in any of the first to fourth types, the insulating plate is a mica plate.

[0024] In the battery device of the fifth type, the insulating plate is a mica plate. Therefore, the insulating plate of the fifth type has high electrical insulation and mechanical strength.

[0025] The battery device of the sixth embodiment is that, in any one of the embodiments 1 to 5, the housing comprises: a lower housing; and an upper housing, wherein the upper housing is integrated with the lower housing to form the housing together, the release valve is provided on the upper surface of the single battery housing, and the non-flammable paper is provided on the top of the inner surface of the upper housing.

[0026] In the battery device of the sixth embodiment, material inside the single cell is discharged upwards from the single cell via a release valve located on the upper surface of the single cell casing. This material sometimes violently impacts an insulating plate located on the top of the inner surface of the upper casing. In this case, the insulating plate may detach from the upper casing and simultaneously come into contact with the terminals of two adjacent single cells. However, because the insulating plate is electrically insulating, no short circuit is generated between the two adjacent single cells via the insulating plate.

[0027] The battery device of the seventh embodiment is, in any one of the embodiments 1 to 6, a battery stack having a plurality of the above-mentioned single cells arranged in a predetermined straight line direction in a top view is disposed in the housing, the above-mentioned insulating plate is a plate extending in the above-mentioned straight line direction, and a single above-mentioned insulating plate is opposite to the above-mentioned release valve of the plurality of above-mentioned single cells.

[0028] In the battery device of the seventh embodiment, a single insulating plate is positioned opposite the release valves of multiple individual cells. Therefore, the number of components in the battery device of the seventh embodiment can be reduced.

[0029] The battery device of the eighth embodiment is that, in the seventh embodiment, in a top view, a plurality of the aforementioned battery stacks are arranged in a gap in a direction orthogonal to the aforementioned straight direction, and two of the aforementioned insulating plates are respectively opposite to the plurality of the aforementioned single cells arranged in the aforementioned straight direction. When viewed along the thickness direction of the aforementioned non-flammable paper, a single intermediate member that overlaps with the aforementioned gap is provided with two of the aforementioned insulating plates.

[0030] In the battery device of the eighth method, the number of components can be reduced compared to the case where two intermediate pieces are placed on the housing in a manner that does not overlap with the gap formed between two adjacent battery stacks.

[0031] The battery device of the ninth embodiment is that, in the eighth embodiment, a single intermediate member is provided on a single non-combustible paper. When the direction orthogonal to the straight line direction when viewed along the thickness direction of the non-combustible paper is defined as the orthogonal direction, the end of the non-combustible paper and the intermediate member on one side of the orthogonal direction is located closer to the other side than the two insulating plates, and the end of the non-combustible paper and the intermediate member on the other side of the orthogonal direction is located closer to the other side than the two insulating plates.

[0032] In the battery device of the ninth method, the phenomenon that a wide area of ​​the casing becomes hot due to the high-temperature gas discharged from the single cell can be suppressed by a single non-flammable paper and a single intermediate component.

[0033] The battery device of the 10th method is that, in any of the 1st to 9th methods, the battery device is mounted on an electric vehicle.

[0034] The battery device of the 10th type is capable of suppressing the phenomenon that the casing of the battery device mounted in an electric vehicle becomes hot due to the influence of substances discharged from the single cell.

[0035] As explained above, the battery device disclosed herein has the excellent effect of suppressing the phenomenon that the casing becomes hot due to the influence of substances discharged from the single cell. Attached Figure Description

[0036] Exemplary embodiments of this disclosure will be described in detail based on the following drawings. Wherein:

[0037] Figure 1 This is a schematic top view showing a portion of the battery device and the body frame component of an electric vehicle equipped with the battery device, according to the embodiment.

[0038] Figure 2 It is along Figure 1 A schematic cross-sectional view of arrow 2-2.

[0039] Figure 3 This is a schematic exploded perspective view of the battery device.

[0040] Figure 4 It is a schematic perspective view of the separate upper shell and cover unit.

[0041] Figure 5 This is a schematic exploded perspective view of the cover unit.

[0042] Figure 6 This is a schematic bottom view of the upper housing and cover unit.

[0043] Figure 7 It is a schematic cross-sectional view of the top plate of the upper casing, the cover unit, and the battery stack.

[0044] Figure 8 It is a schematic 3D diagram of a single battery.

[0045] Figure 9 This is a schematic top view of the lower casing and battery stack.

[0046] Figure 10 It is the mica plate that detaches from the top plate of the upper shell and... Figure 7 Same sectional view. Detailed Implementation

[0047] Hereinafter, the battery device according to the embodiment will be described with reference to the accompanying drawings. In addition, the arrows UP, FR and LH in each figure represent the upper side in the vertical direction of the vehicle, the front side in the longitudinal direction (orthogonal direction) of the vehicle, and the left side in the horizontal direction (straight direction) of the vehicle, respectively.

[0048] like Figure 1 and Figure 2 As shown, the battery device 20 of this embodiment is mounted on a vehicle (electric vehicle) 10. The vehicle 10 of this embodiment is an electric vehicle (BEV).

[0049] The vehicle 10 has a pair of front wheels 11F on the left and right, a pair of rear wheels 11R on the left and right, a pair of rocker arms 12 on the left and right that are part of the vehicle frame components and extend along the front-rear direction of the vehicle, and a pair of crossbeams 14 on the front and rear that are part of the vehicle frame components and extend along the width direction (left-right direction) of the vehicle and are fixed at both ends to the rocker arms 12 on the left and right.

[0050] The battery device 20 of this embodiment has a battery housing 22 and a battery stack 50. The power of the battery device 20 (single battery 52) is supplied, for example, to an electric motor (not shown) that applies driving force to the front wheel 11F and the rear wheel 11R.

[0051] like Figure 2 and Figure 3 As shown, the battery casing 22 has a lower casing 24 and an upper casing 35. The lower casing 24 and the upper casing 35 are integrally molded metal containing iron. Furthermore, the entire surface of the lower casing 24 is coated with a cationic coating 24A, and the entire surface of the upper casing 35 is coated with a cationic coating 35A.

[0052] The lower housing 24 is a hollow body with an opening 25 formed on its upper surface. The lower housing 24 has a base plate 26, a peripheral wall 27, and an outer peripheral flange 28. The peripheral wall 27 has an annular planar shape, and its lower end is connected to the outer peripheral edge of the base plate 26. The outer peripheral flange 28 has an annular planar shape, and its inner peripheral edge is connected to the upper end of the peripheral wall 27.

[0053] The upper shell 35 is a hollow body with an opening 36 formed on its lower surface. The upper shell 35 has a top plate portion 37, a peripheral wall portion 38, and an outer peripheral flange 39. The peripheral wall portion 38 has an annular planar shape, and its upper end is connected to the outer peripheral edge of the top plate portion 37. The outer peripheral flange 39 has an annular planar shape, and its inner peripheral edge is connected to the lower end of the peripheral wall portion 38.

[0054] like Figure 4 As shown, four cover units 42-1, 42-2, 42-3, and 42-4 are fixed on the inner surface (lower surface) of the top plate portion 37 of the upper housing 35. Furthermore, when there is no need to distinguish between the individual cover units, cover units 42-1, 42-2, 42-3, and 42-4 are sometimes collectively referred to as cover unit 42. For example... Figure 5 As shown, the cover unit 42 includes non-combustible paper 44, glass cloth (intermediate component) 46 with a planar shape approximately the same as the non-combustible paper 44, and two mica sheets (insulating boards) 48. The non-combustible paper 44 is a rectangle with a left-right dimension longer than its front-back dimension. The glass cloth 46 has a planar shape approximately the same as the non-combustible paper 44. The mica sheet 48 is a rectangle with a left-right dimension approximately the same as the non-combustible paper 44 and a front-back dimension shorter than the non-combustible paper 44. That is, the mica sheet 48 is a sheet material extending in the left-right direction. Figure 4 As shown, the left-right dimensions of the non-combustible paper 44, glass cloth 46, and mica board 48 are shorter than half the left-right dimensions of the top plate 37. The front-back dimensions of the non-combustible paper 44 and glass cloth 46 are also shorter than half the front-back dimensions of the top plate 37.

[0055] The non-combustible paper 44 is, for example, an inorganic paper with magnesium silicate as its main component, where magnesium silicate is a natural non-asbestos mineral. The non-combustible paper 44 has excellent thermal insulation properties. In other words, the thermal insulation properties of the non-combustible paper 44 are higher than those of the upper shell 35, the glass cloth 46, and the mica board 48. Furthermore, the non-combustible paper 44 has electrical insulation properties. For example, M-thermo thermal insulation material (I-30F) from Awa Paper Co., Ltd. can be used as the non-combustible paper 44. This M-thermo thermal insulation material (I-30F) has high heat resistance (600°C).

[0056] Fiberglass cloth 46 is a fabric woven from glass yarn. Fiberglass cloth 46 has excellent mechanical strength. In other words, the mechanical strength of fiberglass cloth 46 is higher than that of non-combustible paper 44. Furthermore, the thermal insulation properties of fiberglass cloth 46 are higher than those of mica board 48.

[0057] Mica sheet 48 is a sheet material made of mica. As is well known, mica has excellent electrical insulation and heat resistance. The electrical insulation of mica sheet 48 is higher than that of non-combustible paper 44 and glass cloth 46. Furthermore, mica sheet 48 has excellent mechanical strength. In other words, the mechanical strength of mica sheet 48 is higher than that of non-combustible paper 44 and glass cloth 46.

[0058] like Figure 4 , Figure 6 and Figure 7 As shown, the upper surface of glass cloth 46 is fixed to the lower surface of non-combustible paper 44 using heat-resistant double-sided tape (not shown). In a top view, the outer periphery of the non-combustible paper 44 overlaps the outer periphery of the glass cloth 46 vertically. Furthermore, the upper surfaces of two mica sheets 48 are fixed to the lower surface of the glass cloth 46 using multiple heat-resistant double-sided tapes (not shown). In a top view, the left edge of the glass cloth 46 overlaps the left edge of the two mica sheets 48 vertically, and the right edge of the glass cloth 46 overlaps the right edge of the two mica sheets 48 vertically.

[0059] like Figure 4 and Figure 6As shown, in the following description, the two mica plates 48 of the glass cloth 46 disposed in the cover unit 42-1 are sometimes referred to as mica plates 48A and 48B, respectively. Mica plate 48B is located behind mica plate 48A. The leading edge of the non-combustible paper 44 and the glass cloth 46 of the cover unit 42-1 is located further forward than the leading edge of mica plate 48A, and the trailing edge of the non-combustible paper 44 and the glass cloth 46 of the cover unit 42-1 is located further backward than the trailing edge of mica plate 48B. Alternatively, the two mica plates 48 of the glass cloth 46 disposed in the cover unit 42-2 are sometimes referred to as mica plates 48C and 48D, respectively. Mica plate 48D is located behind mica plate 48C. The leading edges of the non-combustible paper 44 and glass cloth 46 in cover unit 42-2 are positioned forward of the leading edge of mica plate 48C, and the trailing edges of the non-combustible paper 44 and glass cloth 46 in cover unit 42-2 are positioned rearward of the trailing edge of mica plate 48D. Additionally, the two mica plates 48 disposed on the glass cloth 46 in cover unit 42-3 are sometimes referred to as mica plates 48E and 48F, respectively. Mica plate 48F is located behind mica plate 48E. The leading edges of the non-combustible paper 44 and glass cloth 46 in cover unit 42-3 are positioned forward of the leading edge of mica plate 48E, and the trailing edges of the non-combustible paper 44 and glass cloth 46 in cover unit 42-3 are positioned rearward of the trailing edge of mica plate 48F. Additionally, the two mica plates 48 disposed on the glass cloth 46 in cover unit 42-4 are sometimes referred to as mica plates 48G and 48H, respectively. Mica plate 48H is located behind mica plate 48G. The leading edge of the non-combustible paper 44 and glass cloth 46 of cover unit 42-4 is located in front of the leading edge of mica plate 48G, and the trailing edge of the non-combustible paper 44 and glass cloth 46 of cover unit 42-4 is located behind the trailing edge of mica plate 48H.

[0060] And, as Figure 6 and Figure 7 As shown, on the inner surface (lower surface) of the top plate portion 37 of the upper housing 35, four pieces of non-combustible paper 44, consisting of cover units 42-1, 42-2, 42-3, and 42-4, are fixed to the upper surface using heat-resistant double-sided tape (not shown). More specifically, cover unit 42-1 is fixed to the left half of the front portion of the top plate portion 37, cover unit 42-2 is fixed to the right half of the front portion of the top plate portion 37, cover unit 42-3 is fixed to the left half of the rear portion of the top plate portion 37, and cover unit 42-4 is fixed to the right half of the rear portion of the top plate portion 37. Figure 6As shown, a gap GP1 is formed between the right edge of cover unit 42-1 and the left edge of cover unit 42-2, and a gap GP1 is formed between the right edge of cover unit 42-3 and the left edge of cover unit 42-4. Furthermore, a gap GP2 is formed between the rear edge of cover unit 42-1 and the front edge of cover unit 42-3, and a gap GP2 is formed between the rear edge of cover unit 42-2 and the front edge of cover unit 42-4.

[0061] like Figure 3 As shown, eight battery stacks 50A, 50B, 50C, 50D, 50E, 50F, 50G, and 50H are arranged inside the lower housing 24. Each battery stack 50A, 50B, 50C, 50D, 50E, 50F, 50G, and 50H has multiple individual cells 52 arranged in the left-right direction, multiple busbars (not shown in the figure), and a cooler (not shown in the figure). Furthermore, when there is no need to distinguish between the individual battery stacks, battery stacks 50A, 50B, 50C, 50D, 50E, 50F, 50G, and 50H are sometimes collectively referred to as battery stack 50. Figure 8 As shown, a release valve 54 and a pair of external electrodes 56 are provided on the upper surface of the metal single-cell housing 53, which forms the shape of the single-cell battery 52. ​​One external electrode 56 is the positive electrode, and the other external electrode 56 is the negative electrode. The release valve 54 opens when the pressure in the internal space of the single-cell battery 52 reaches a predetermined pressure, discharging the contents stored in the internal space of the single-cell housing 53 to the outside. In this embodiment, the release valve 54 is separate from the single-cell housing 53 and can move relative to the single-cell housing 53. However, the release valve 54 may also be formed in a vulnerable part of the single-cell housing 53. For example, a vulnerable part is formed in a portion of the single-cell housing 53 where the wall is thinner than the periphery.

[0062] like Figure 9As shown, battery stacks 50A, 50B, 50C, 50D, 50E, 50F, 50G, and 50H are housed inside the lower housing 24. More specifically, the lower surfaces of battery stacks 50A and 50B are fixed to the left half of the front portion of the bottom plate portion 26 of the lower housing 24, the lower surfaces of battery stacks 50C and 50D are fixed to the right half of the front portion of the bottom plate portion 26, the lower surfaces of battery stacks 50E and 50F are fixed to the left half of the rear portion of the bottom plate portion 26, and the lower surfaces of battery stacks 50G and 50H are fixed to the right half of the rear portion of the bottom plate portion 26. Gap GP3 is formed between battery stacks 50A and 50B, between battery stacks 50C and 50D, between battery stacks 50E and 50F, and between battery stacks 50G and 50H. Furthermore, gaps GP4 are formed between battery stacks 50A and 50C, between battery stacks 50B and 50D, between battery stacks 50E and 50G, and between battery stacks 50F and 50H.

[0063] A sealing element (not shown) is integrally provided on the upper surface of the outer peripheral flange 28 of the lower housing 24, which houses the battery stacks 50. The outer peripheral flange 39 of the upper housing 35 rests on the upper surface of the outer peripheral flange 28 and the sealing element. Furthermore, the outer peripheral flanges 28 and 39 are fixed to each other at multiple locations by multiple fixing components. These fixing components include, for example, bolts passing through the outer peripheral flanges 28 and 39 and nuts that can be threaded into the bolts. Thus, the battery assembly 20 is completed.

[0064] If battery device 20 is completed, then as follows Figure 9 As shown, mica plates 48A, 48B, 48C, 48D, 48E, 48F, 48G, and 48H are positioned directly above the release valves 54 of the battery stacks 50A, 50B, 50C, 50D, 50E, 50F, 50G, and 50H. Figure 7 As shown, gaps are formed between each release valve 54 and each mica plate 48.

[0065] The battery casing 22 of this battery device 20 is supported by the rocker arm 12 and the crossbeam 14. That is, as Figure 1 and Figure 2 As shown, with the top plate portion 37 and peripheral wall portion 38 of the upper housing 35 located in the space surrounded by the rocker arms 12 and crossbeams 14, the outer peripheral flanges 39 contact the lower surfaces of each rocker arm 12 and each crossbeam 14 from below. Furthermore, the lower surfaces of the rocker arms 12 and multiple locations of the outer peripheral flanges 28 and 39 are fixed to each other by multiple fixing components. These fixing components include, for example, bolts penetrating the base plate of the rocker arm 12, the outer peripheral flanges 28 and 39, and welded nuts that can be threaded into the bolts and fixed to the upper surface of the base plate of the rocker arm 12.

[0066] The upper surface of the top plate portion 37 of the upper housing 35 constitutes the floor panel of the vehicle 10. In addition, the upper surface of the top plate portion 37 is covered with a cloth-like padding material (not shown).

[0067] (Functions and Effects)

[0068] Next, the function and effects of the implementation method will be explained.

[0069] For example, if a short circuit occurs in one of the individual cells 52 of the battery device 20, the internal pressure of that cell 52 rises. If the internal pressure of the cell 52 reaches a predetermined value, the release valve 54 opens, violently expelling the hot internal component disposed within the cell 52 upwards through the release valve 54 towards the cell housing 53. This internal component includes, for example, internal electrodes 55 (current collector terminals) (see...). Figure 7 The electrolyte and gas. The internal electrode 55 and the electrode body (not shown) disposed within the single-cell housing 53, and the external electrode 56 disposed on the upper surface of the single-cell housing 53 (see reference). Figure 8 Electrical connection.

[0070] For example, if the high-temperature internal material is violently discharged upwards from the release valve 54 of one single cell 52 of the battery stack 50A, then as Figure 7 As shown, for example, the internal electrode 55, which is hot and heavier than other built-in components (e.g., gas GS), violently impacts the mica plate 48A of the cover unit 42-1, located directly above the release valve 54. However, the mechanical strength of the mica plate 48A and the glass cloth 46 of the cover unit 42-1 is higher than that of the non-combustible paper 44. That is, the mechanical strength of the mica plate 48A and the glass cloth 46 is high, especially that of the mica plate 48A. Therefore, even if the internal electrode 55 violently impacts the mica plate 48A, the possibility of the non-combustible paper 44 of the cover unit 42-1 peeling off from the inner surface of the top plate portion 37 of the upper housing 35 is small. Therefore, the heat transfer from the hot internal electrode 55 discharged upward from the single cell 52 to the upper housing 35 can be suppressed by the non-combustible paper 44 and the glass cloth 46. Therefore, for the battery device 20, it is possible to suppress the phenomenon that the battery housing 22 becomes hot due to the influence of the hot built-in components discharged from the single cell 52. Therefore, the floor panel of the top plate portion 37 of the upper housing 35 is less likely to become hot.

[0071] Furthermore, compared to lightweight built-in components (such as gas GS), heavier built-in components (such as internal electrode 55) tend to have a narrower diffusion range after being discharged from release valve 54. Therefore, the heavier built-in component, i.e., internal electrode 55, is less likely to violently impact glass cloth 46.

[0072] Furthermore, the inventors discovered through experiments that when the cover unit 42 only contains non-combustible paper 44, the non-combustible paper 44 is likely to peel off from the top plate 37 when the high-temperature interior material violently impacts the non-combustible paper 44. Additionally, when the cover unit 42 only contains non-combustible paper 44 and glass cloth 46, or when the cover unit 42 only contains non-combustible paper 44 and mica plates 48A and 48B, the non-combustible paper 44 is also likely to peel off from the top plate 37 when the interior material violently impacts the cover unit 42.

[0073] Furthermore, when the built-in components of the single battery 52 violently impact the mica plate 48, such as Figure 10 As shown, the cover unit 42 sometimes detaches downwards from the top plate portion 37. In this case, the mica plate 48 sometimes comes into contact with the multiple individual cells 52 located directly below (in... Figure 10 The diagram only shows the external electrode 56 of a single cell 52 located on the upper surface of the single cell housing 53. That is, the mica plate 48 may simultaneously contact the external electrodes 56 of multiple single cells 52 when the release valve 54 is not open. However, because the mica plate 48 is electrically insulating, no short circuit will occur between two adjacent single cells 52 via the mica plate 48. Therefore, the possibility of a single cell 52 with the release valve 54 not open becoming hot due to the mica plate 48 is small.

[0074] In this way, a cover unit 42 with excellent heat insulation, mechanical strength and electrical insulation is formed by combining non-combustible paper 44, glass cloth 46 and mica board 48 with different properties. Moreover, since the cover unit 42 is provided on the top plate portion 37 of the upper housing 35 in a manner opposite to the single battery 52 (release valve 54), the battery device 20 can perform the above-mentioned functions and effects.

[0075] Furthermore, since the battery unit 20 is located in the vehicle 10, moisture such as rainwater can easily adhere to the lower housing 24 and the upper housing 35. Although the lower housing 24 and the upper housing 35 are made of iron-containing metal materials, the entire surface of the lower housing 24 and the upper housing 35 is coated with cationic coating 24A and 35A. Therefore, although moisture can easily adhere to the surface of the lower housing 24 and the upper housing 35, the lower housing 24 and the upper housing 35 are less prone to rust.

[0076] Furthermore, the cationic coated portion of the battery casing 22 is prone to spontaneous combustion when it reaches high temperatures. However, when the hot interior material is discharged towards the top plate portion 37 from the release valve 54 of any single cell 52 as described above, the top plate portion 37 is unlikely to reach high temperatures. Therefore, the possibility of the top plate portion 37 of the upper casing 35 spontaneously combusting due to the hot interior material discharged upward from the release valve 54 is small.

[0077] In addition, such as Figure 7As shown, compared to the discharge range of the internal electrode 55 from the single cell 52 that is discharged and violently impacts the mica plate 48, the discharge range of the high-temperature gas GS contained in the built-in, which is lighter than the internal electrode 55, is more easily widened. However, when viewed in the thickness direction (vertical direction) of the non-combustible paper 44, the area of ​​the non-combustible paper 44 and the glass cloth 46 is larger than the area of ​​the mica plate 48. Therefore, the phenomenon of the top plate portion 37 becoming hot due to the high-temperature gas GS discharged from the release valve 54 over a wider range can be suppressed by the non-combustible paper 44 and the glass cloth 46. Furthermore, even if the gas GS violently contacts the mica plate 48 or the glass cloth 46, the possibility of the non-combustible paper 44 peeling off from the inner surface of the top plate portion 37 is small.

[0078] Furthermore, each mica plate 48 of each cover unit 42 is positioned vertically opposite the release valve 54 of each individual cell 52 contained in the battery stack 50 located directly below. Therefore, compared to the case where each cover unit 42 has the same number of mica plates as the release valve 54 of each individual cell 52 contained in the battery stack 50 located directly below, the battery device 20 has fewer components.

[0079] And, as Figure 6 and Figure 9 As shown, each cover unit 42 has a portion 42P located directly above the gap GP3 of the non-combustible paper 44 and glass cloth 46, which is formed between two battery stacks 50 arranged directly below each other in the front-back direction. That is, when the battery device 20 is viewed vertically, the gap GP3 overlaps with a portion (portion 42P) of each individual non-combustible paper 44 and glass cloth 46. Each portion 42P is separated from the release valve 54 of the individual battery 52 of the battery stack 50 in the front-back direction from a top view. Therefore, the possibility of the high-temperature contents discharged from the release valve 54 of the individual battery 52 coming into contact with each portion 42P is small. Therefore, each cover unit 42 can also be separated into two portions located before and after each portion 42P. However, in this case, eight cover units need to be provided on the top plate portion 37, increasing the number of components in the battery device 20. In contrast, in the case where each cover unit 42 has a portion 42P, as in the battery device 20 of this embodiment, the number of cover units 42 provided on the top plate portion 37 is four. Therefore, for the battery device 20, compared to the case where each cover unit 42 does not have a portion 42P, the number of components can be reduced. Therefore, compared to the case where each cover unit 42 does not have a portion 42P, the assembly operation of the battery device 20 is easier.

[0080] The battery device according to the embodiments has been described above, but the battery device can be appropriately modified without departing from the spirit of this disclosure.

[0081] For example, each enclosure unit 42 may also have an intermediate component different from the glass cloth 46. This intermediate component has higher mechanical strength than the non-combustible paper 44. Furthermore, this intermediate component preferably has higher thermal insulation properties than the mica board 48. Additionally, this intermediate component preferably has electrical insulation properties. Such an intermediate component may include, for example, a silica fabric or a ceramic sheet.

[0082] Additionally, each enclosure unit 42 may also have an insulating plate different from the mica plate 48. This insulating plate has higher electrical insulation properties than the non-combustible paper 44. Furthermore, the electrical insulation properties of the insulating plate may also be higher than those of the intermediate component. Additionally, this insulating plate has higher mechanical strength than the non-combustible paper 44. Furthermore, this insulating plate may also have higher mechanical strength than the intermediate component. Such an insulating plate may, for example, comprise a plate made of a thermosetting resin. Specific examples of thermosetting resins include, for instance, unsaturated polyester.

[0083] The cover unit 42 may also be located at a location different from the inner surface of the top plate portion 37 of the battery housing 22. For example, if the battery device 20 has only four battery stacks 50A, 50C, 50F, and 50H, and a release valve 54 is provided on the front surface of each individual cell 52 of battery stacks 50A and 50C and on the rear surface of each individual cell 52 of battery stacks 50F and 50H, the cover unit 42 may be provided on at least one of the front and rear portions of the peripheral wall portion 27 of the lower housing 24 and the front and rear portions of the peripheral wall portion 38 of the upper housing 35.

[0084] Alternatively, a heat-resistant adhesive can be used to fix the non-combustible paper 44 of the cover unit 42 to the inner surface of the battery casing 22. Similarly, the non-combustible paper 44 of the cover unit 42 can be fixed to the intermediate component with a heat-resistant adhesive, and the intermediate component can be fixed to the insulating plate with a heat-resistant adhesive.

[0085] The number of battery stacks 50 stored in the battery casing 22 can also be different from 8.

[0086] The battery stack 50 housed in the battery casing 22 may also have multiple individual cells 52 arranged in a direction different from the left-right direction. In this case, the insulating plate of the cover unit 42 extends in a direction parallel to the arrangement direction of the individual cells 52 in a top view, and the insulating plate and the release valves 54 of the multiple individual cells 52 are opposite each other in the thickness direction of the insulating plate.

[0087] Alternatively, non-flammable paper 44 may be provided on the entire inner surface of the top plate portion 37 of the upper housing 35, or on the entire inner surface of the upper housing 35, or on the entire inner surface of the battery housing 22.

[0088] The cover unit 42 may also have the same number of insulating plates as the opposing release valves 54 and each release valve 54 is opposite to it.

[0089] The vehicle may also be an electric vehicle, different from an electric vehicle, and equipped with an electric motor that utilizes the power of the battery device 20. For example, the vehicle may also be a hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHEV).

Claims

1. A battery device, wherein, have: Multiple individual cells, each individual cell having a cell housing equipped with a release valve that opens when the internal pressure reaches a predetermined value; The casing houses multiple individual batteries. Non-flammable paper is disposed on at least a portion of the inner surface of the housing; An intermediate component, disposed on the side of the non-combustible paper opposite to the inner surface, has higher mechanical strength than the non-combustible paper; as well as An insulating plate, disposed on the side of the intermediate member opposite to the non-combustible paper, opposite the release valve, and possessing electrical insulation and higher mechanical strength than the non-combustible paper, is also provided. The non-combustible paper and the intermediate component have higher thermal insulation properties than the insulating board.

2. The battery device according to claim 1, wherein, The shell is made of a material containing iron. The inner surface of the housing was coated with a cationic coating.

3. The battery device according to claim 1 or 2, wherein, When viewed along the thickness direction of the non-combustible paper, the area of ​​the non-combustible paper and the intermediate component is larger than the area of ​​the insulating board.

4. The battery device according to claim 1 or 2, wherein, The intermediate component is glass cloth.

5. The battery device according to claim 1 or 2, wherein, The insulating board is a mica board.

6. The battery device according to claim 1 or 2, wherein, The housing includes: Lower shell; and The upper housing is integrated with the lower housing to form the housing together. The release valve is provided on the upper surface of the single battery casing. The non-flammable paper is provided on the top of the inner surface of the upper housing.

7. The battery device according to claim 1 or 2, wherein, A battery stack having a plurality of said individual cells arranged in a prescribed straight line direction in a top view is disposed within the housing. The insulating board is a sheet material extending along the straight line direction. Each of the insulating plates is opposite the release valves of the plurality of individual cells.

8. The battery device according to claim 7, wherein, From a top-down view, the multiple battery stacks are arranged in a gap-like pattern in a direction orthogonal to the straight line direction. The two insulating plates are respectively positioned opposite to the plurality of individual cells arranged in the straight direction. When viewed along the thickness direction of the non-flammable paper, the single intermediate piece overlapping the gap is provided with two insulating plates.

9. The battery device according to claim 8, wherein, Each of the aforementioned non-combustible paper pieces is provided with a single intermediate component. When the direction orthogonal to the straight line direction when viewed along the thickness direction of the non-combustible paper is defined as the orthogonal direction, The end of the non-combustible paper and the intermediate component on one side of the orthogonal direction is located closer to one side than the two insulating boards, and the end of the non-combustible paper and the intermediate component on the other side of the orthogonal direction is located closer to the other side than the two insulating boards.

10. The battery device according to claim 1 or 2, wherein, The battery device is mounted on an electric vehicle.

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