JPH1186812A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery, in which damages, deformations or strains of a heat-insulating container or a battery module can be prevented, and which can be manufactured easily with a low cost and also disassembly work of the battery is easy. SOLUTION: This battery is composed of a battery module 7 by assembling and mutually connecting plural standing unit cells 6, a heat-insulating container 1 in which the battery module 7 is stored, and a granular fire-proof material 13 filled in the aperture between the heat-insulating container 1 and the unit cells 6. A wall 15 for reinforcing the heat-insulating container 1 is formed so as to be inscribed on at least the side of the heat-insulating container 1 out of the space formed between the inside surface of the heat-insulating container 1 and unit cells 6a located on the outermost circumference of the battery module 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembled battery in which a heat insulating container or a battery module is prevented from being damaged, deformed, or distorted by a granular fireproof material.

[0002]

2. Description of the Related Art Generally, an assembled battery has a structure in which a plurality of unit cells are erected and assembled in a heat insulating container and connected to each other to form a battery module. In such an assembled battery, the cells are approximately 300, such as sodium-sulfur cells.
For those that operate at a high temperature of ℃ and incorporate a highly reactive active material, the inside of the insulated container should be able to cope with situations such as breakage of cells, abnormal heating, or leakage of the active material. The gap between the placed unit cell and the heat insulating container and the gap between the unit cells are filled with, for example, a particulate fireproof material having heat resistance, corrosion resistance, and electric insulation such as selben. (Japanese Unexamined Patent Publication No. 3-283272,
No. 51-2733).

[0003] In the battery pack having the above configuration, the particulate fireproof material is in a flowable state, and a heat cycle of 280 to 360 ° C is repeated every 24 hours during long-term operation. . Therefore, as shown in FIG.
The granular fireproof material 3 filled in the upper part of the battery module 27
3 shows that each time the heat insulating container 21 thermally expands at a high temperature of the heat cycle, the heat insulating container 21 gradually enters the gap 38 formed between the inner surface of the heat insulating container 21 and the battery module 27 (FIG. 2 (b)).

In this case, the granular fireproof material 3
Due to 3, the heat insulating container 21 or the battery module 27 may be squeezed and deformed or deformed (FIG. 2C), and may be damaged in the worst case. Also, due to the reduction of the granular fireproof material on the upper part of the unit cell, the upper part of the unit cell is exposed, so that not only there is a problem from the viewpoint of disaster prevention, but also the electric connection member on the upper part of the battery module is damaged. There were problems such as a structural problem.

Therefore, as shown in FIG. 3, for example, a granular fixing material in which a thermosetting binder is mixed from the bottom of the heat insulating container 41 to the vicinity of the upper surface of the cell 46 is placed in the heat insulating container 41 on which the cells 46 are placed. There has been proposed an assembled battery in which the filling material 54 is filled and the remaining upper gap is filled with the conventional granular fireproof material 53 (Japanese Patent Publication No. 8-21427).

According to the battery pack, the granular fixing material 54
Then, by filling the particulate fireproof material 53 and then thermally curing the binder, the unit cells 46 and eventually the entire battery module 47 are fixed by the particulate fixing material 54. Therefore, the granular fireproof material 43 did not enter between the battery module 47 and the inner surface of the heat insulating container 41, and the situation where the heat insulating container or the battery module was squeezed to cause distortion, deformation, or breakage was reduced.

[0007]

However, in the above-mentioned assembled battery, although the particulate fireproof material does not enter between the battery module and the inner surface of the heat insulating container, two kinds of granular materials are precisely stacked and filled without variation. It is technically difficult to do so, the particulate fixing material is extremely expensive due to the mixing of a binder, etc., which increases the manufacturing cost of the entire assembled battery, and the disassembly work of the battery due to the solidified particulate fixing material There is also a problem such that it becomes difficult.

The present invention has been made in view of such problems of the related art, and an object of the present invention is to prevent breakage, deformation, or distortion of a heat insulating container or a battery module, and simplify manufacturing. Another object of the present invention is to provide an assembled battery which has a low production cost and can be easily disassembled.

[0009]

Means for Solving the Problems According to the present invention, a plurality of unit cells are erected and assembled and connected to each other, a battery module housing the battery module, the heat insulating container and the unit. A battery pack comprising: a particulate fireproof material filled in a gap between the battery and a battery; and a space formed by an inner surface of the heat-insulating container and a cell positioned at the outermost periphery of the battery module. Among them, there is provided an assembled battery, wherein a wall portion for reinforcing the heat insulating container is formed so as to be inscribed at least in the side surface of the heat insulating container.

In the battery assembly of the present invention, it is preferable that a corrugated sheet be interposed between the inner surface of the heat insulating container and the wall, and the unit cell located on the inner surface of the heat insulating container and the outermost periphery of the battery module. As filling the space formed by the battery,
It is preferable to form a wall formed by thermosetting the granular fixing material. Further, the battery pack of the present invention can be suitably used for a battery pack in which the unit cells are sodium-sulfur unit cells.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Since the present invention relates to a battery pack, first, the configuration of the whole battery pack will be described with reference to an example of a sodium-sulfur battery pack (hereinafter, referred to as a NAS battery pack).

As shown in FIG. 4, the NAS battery is usually formed in a box shape in which a heat insulating material 64 is interposed between an outer wall 62 and an inner wall 63, and an upper opening of the heat insulating container 61. Is sealed by a lid 65 in which a heat insulating material 64 is interposed between an outer wall 62 and an inner wall 63, similarly to the heat insulating container 61.

As shown in FIG. 5, a cushioning material 68, an electric heater 69, a reinforcing plate 7
0, a mica sheet 71 for electrical insulation is laminated and laid, and a mica sheet 72 is similarly arranged on the back surface of the lid 5. Further, the battery module 67 is provided in the heat insulating container 61.
Are formed upright, and a granular fireproof material 73 is provided in the gap between the inner surface of the heat insulating container 61 and the cell 66.
Is filled.

[0014] In the case of a NAS battery pack,
In the unit cell 66, metallic sodium and sulfur, which are active materials, are stored separately by a solid electrolyte tube, and an electric heater 69 laid on the inner bottom surface of the heat insulating container 61 is used.
By heating the inside of the heat insulating container 61 to 300 to 350 ° C., both the active materials are melted and ionized. A predetermined energy is obtained by an electrochemical reaction of the ionized active material.

Hereinafter, the assembled battery of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the illustrated example. The assembled battery of the present invention is, as shown in FIG.
A wall portion 15 for reinforcing the heat insulating container 1 is formed so as to be inscribed in the side surface. With such a configuration, the particulate fireproof material 13 does not enter between the battery module 7 and the inner surface of the heat insulating container 1 even if the entire battery module 7 is not fixed as in the conventional case. Can be prevented from being distorted, deformed or damaged by being pressed.

In the present invention, the wall portion 15 refers to a portion which is inscribed in a side surface of the heat insulating container 1 and is provided so as to surround the outer periphery of the battery module 7. The wall portion 15 reduces the difference in thermal expansion between the heat insulating container 1 and the granular fireproof material 13 and reinforces the side surface of the heat insulating container 1, so that the heat insulating container 1 is less likely to thermally expand.

The thickness of the wall 15 is not particularly limited as long as the above effects can be ensured, and should be appropriately selected depending on the size of the heat insulating container 1, the material of the wall 15, and the like. For example, width 1300mm, depth 1800mm, height 450mm,
In the case of a heat insulating container having a thickness of 40 to 50 mm on the side surface of the container, it is preferable that the thickness be at least 10 mm or more. Also, for the same reason, it is preferable that the height of the wall is equal to or higher than the upper surface of the battery module.

The material of the wall portion 15 is not particularly limited as long as the above effects can be ensured, but a granular fixing material mixed with a thermosetting binder can be suitably used as in the conventional case. The granular fixing material is preferable because it can be easily handled because it is granular at the time of filling, and can be hardened after heating to ensure strength.

In addition, there is a problem in that the granular fixing material is extremely expensive, but in the present invention, unlike the related art, the amount of the granular fixing material to be used is not fixed to the entire battery module but only to the periphery thereof. It can be reduced to about 1/3 of the conventional one. Further, since there are few solidified portions due to the granular fixing material, the disassembling operation at the time of disassembling the battery becomes easy.

In the case where the granular fixing material is used, as shown in FIG. 1, the space formed by the inner surface of the heat insulating container 1 and the cell 6 a located at the outermost periphery of the battery module 7 is filled. It is preferable from the viewpoint of manufacturing that the wall portion 15 be formed. Specifically, for example, as shown in FIG. 6, only the upper surface of the battery module 7 is covered with a pattern 16 or the like, and then the granular fixing material 14 is filled in the gap between the heat insulating container 1 and the battery module 7.

By doing so, the granular fixing material 14 is placed inside the battery module 7 in which the cells 6 are arranged in a close-packed manner.
The granular fixing material 14 is filled only in the space formed by the inner surface of the heat insulating container 1 and the unit cell 6a located on the outermost periphery of the battery module 7 without entering. After removing the pattern 16 and the like, the granular fireproof material 13 is filled from above, whereby the assembled battery having the wall portion 15 can be manufactured relatively easily.

It is further preferable that a corrugated sheet is interposed between the wall and the inner surface of the heat insulating container. By doing so, the difference in thermal expansion between the heat insulating container and the wall is further reduced, and damage to the wall due to repetition of the heat cycle can be prevented.

As the corrugated sheet, as shown in FIG. 9B, a corrugated sheet 17 in which a single plate is alternately bent as shown in FIG. A single-sided corrugated sheet 18 in which corrugated projections are continuously formed only on one surface of a single plate can also be used.

However, the single-sided corrugated sheet 18 is preferable in that a gap is not easily formed between the heat insulating container 1 and the corrugated sheet, and the granular fixing material or the like does not easily enter the gap when the granular fixing material or the granular fireproof material is filled. More preferred. Although the material of the corrugated sheet is not particularly limited, it is preferable that the corrugated sheet is made of light-weight mica having high electrical insulation and corrosion resistance.

[0025]

Hereinafter, an example in which the present invention is applied to a sodium-sulfur battery will be described. (Example 1) As shown in FIG. 8, a box-shaped heat-insulating container 1 in which a heat-insulating material is interposed between an outer wall and an inner wall is prepared. 9, a reinforcing plate 10, and a mica sheet 11 for electrical insulation are sequentially laminated and laid. Next, the plurality of unit cells 6 are erected on the upper surface of the mica sheet 11 and electrically connected to form the battery module 7.

Further, a mica-made corrugated sheet 17 is inscribed on the side surface of the heat insulating container 1, and only the upper surface of the battery module 7 is covered with a pattern, and then, between the corrugated sheet 17 and the outer peripheral portion of the battery module 7. The granular fixing material 14 is filled. After filling the granular fixing material 14, the pattern is removed and the battery module 7 is removed.
Are filled with the granular fireproof material 13 in the space between the unit cells 6 and other parts. The assembled battery thus manufactured is subjected to a high-temperature operation during a pre-shipment inspection to cure the thermosetting binder contained in the granular fixing material 14 and form the wall 15.

Example 2 As shown in FIG. 9, after the flat surface of a single-sided corrugated sheet 18 made of mica is installed in contact with the side surface of the heat insulating container 1, the granular fixing material 14 is formed in the same manner as in Example 1. May be filled and thermally cured to form the wall portion 16. In this embodiment, a gap is hardly formed between the heat insulating container and the corrugated sheet, and the granular fixing material and the like are hardly penetrated into the gap when the granular fixing material or the granular fireproof material is filled, compared to the first embodiment. preferable.

[0028]

As described above, according to the battery pack of the present invention, since the wall is formed in contact with the heat insulating container,
Breakage, deformation, or distortion of the heat insulating container or the battery module can be prevented. In addition, the amount of the extremely expensive granular fixing material used can be reduced, and the process of filling two technically difficult fillers, that is, the granular fixing material and the particulate fireproof material, is eliminated. It is possible to provide an assembled battery with low manufacturing cost and easy dismantling of the battery.

[Brief description of the drawings]

FIG. 1 is a side cross-sectional view (a) and an AA ′ top cross-sectional view (b) showing an embodiment of the battery assembly of the present invention.

FIG. 2 is a schematic explanatory view (a) showing an example of a conventional assembled battery;
(b) and (c).

FIG. 3 is a side sectional view showing one embodiment of a conventional collective battery.

FIG. 4 is a side cross-sectional view showing the configuration of the entire normal sodium-sulfur battery.

FIG. 5 is a schematic explanatory view of a side cross-sectional view in which a part of the assembled battery of FIG. 4 is enlarged.

6A and 6B are a schematic explanatory view showing a side cross section and a top view showing a method of filling a granular fixing material.

FIGS. 7 (a) and 7 (b) are schematic explanatory views showing side cross sections of the method for manufacturing a battery assembly of the present invention.

FIG. 8 is a schematic explanatory view showing a side cross section of one embodiment of the assembled battery of the present invention, and FIG.

FIG. 9 is a schematic explanatory view showing a side cross section of another embodiment of the collective battery of the present invention, and FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Insulated container, 2 ... Outer wall, 3 ... Inner wall, 4 ... Insulation material, 5 ...
Lid, 6 single cell, 6a outermost unit cell, 7 battery module, 8 cushioning material, 9 electric heater, 10 reinforcing plate,
11: Mica sheet for insulation (bottom of heat insulating container), 12: Mica sheet for insulation (back of lid), 13: Granular fireproof material, 1
4 ... granular fixing material, 15 ... wall, 16 ... paper pattern, 17 ... corrugated sheet, 18 ... single-side corrugated sheet, 21 ... heat insulating container, 22
... outer wall, 23 ... inner wall, 24 ... heat insulating material, 25 ... lid, 26
... cell, 27 ... battery module, 32 ... mica sheet for insulation (back side of lid), 33 ... granular fireproof material, 34 ... granular fixing material, 38 ... void, 41 ... heat insulating container, 42 ... outer wall, 4
3 ... inner wall, 44 ... heat insulating material, 45 ... lid, 46 ... unit cell,
47: Battery module, 53: Granular fireproof material, 54: Granular fixing material, 61: Insulated container, 62: Outer wall, 63: Inner wall, 6
DESCRIPTION OF SYMBOLS 4 ... Heat insulating material, 65 ... Lid, 66 ... Single cell, 67 ... Battery module, 68 ... Buffer material, 69 ... Electric heater, 70 ... Reinforcement plate, 71 ... Mica sheet for insulation (Bottom of heat insulating container), 7
2. Insulating mica sheet (back side of lid), 73: granular fireproof material.

Claims (4)

[Claims] 1. A battery module comprising a plurality of unit cells erected and assembled together and connected to each other, an insulating container for accommodating the battery module, and a granular material filled in a gap between the insulating container and the unit cell. An assembled battery including a fireproof material, wherein at least a space formed by an inner surface of the heat-insulating container and a cell positioned at an outermost periphery of the battery module is inscribed in at least the side surface of the heat-insulating container. As described above, the assembled battery has a wall for reinforcing the heat insulating container. 2. The battery pack according to claim 1, wherein a corrugated sheet is interposed between the inner surface of the heat insulating container and the wall. 3. A wall formed by thermosetting a granular fixing material so as to fill a space formed by an inner surface of the heat-insulating container and a unit cell positioned at the outermost periphery of the battery module. Or the collective battery according to 2. 4. The collective battery according to claim 1, wherein the unit cell is a sodium-sulfur unit cell.