JPH11273744A - Nonaqueous system secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rectangular nonaqueous system secondary battery with high mechanical strength. SOLUTION: A layered product 1 formed by stacking a plurality of unit cells formed by laminating a positive electrode plate and a negative electrode plate through a separator, or a wound body formed by spirally winding the unit cell or the layered product of the unit cells is housed in a box-shaped can 11 having an opening part at one end and a rib on at least one wall surface of a pair of wall surfaces facing each other having the maximum area, and the opening part of the can 11 is sealed with a cover 17 in an insulated state, and the layered product 1 or the wound body is interposed between the cover 17 and a bottom wall rib 16 of the can 11, or between a pair of facing wall surfaces whose at least one has the wall surface rib.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rectangular non-aqueous secondary battery having a large mechanical strength and being hardly deformed, and particularly to a thin battery.

[0002]

2. Description of the Related Art In recent years, cordless and portable electronic devices have been desired, and as electronic devices have become smaller and lighter, the ratio of batteries, which are energy sources, to the entire electronic devices has increased. There is an increasing demand for non-aqueous secondary batteries that can be expected to have a high density. For example, lithium ion secondary batteries having a positive electrode and a negative electrode containing an active material capable of inserting and releasing lithium ions have been widely used as power sources for mobile phones, video cameras, and the like. Conventionally, cylindrical or square metal containers are often used as battery cases.

[0003]

However, with the demand for smaller and lighter batteries, when mounting batteries in electronic devices, the space occupied by the batteries is reduced. There is a problem that the strength is reduced and the battery is easily deformed. Further, in addition to the space for the battery body, a wiring space for electric wires for connection between the battery terminals and the electronic device is required, so that there is a problem that miniaturization is difficult. Furthermore, when a mechanical shock or vibration is applied during manufacturing or use of the product, the stacked body or wound body of the electrodes in the battery case moves or vibrates, and thus the electrical connection between the positive electrode or the negative electrode and the terminal is made. There is also a problem that the battery may be defective and the performance of the battery may be reduced.

Therefore, the present invention solves the above-mentioned problems, is easy to manufacture, is not easily deformed even when thin, can reduce wiring space, and has a low performance even when subjected to mechanical shock or vibration. It is an object of the present invention to provide a thin, rectangular, non-aqueous secondary battery with high reliability without a drop.

[0005]

SUMMARY OF THE INVENTION The present invention uses a box having one end opened and having a wall rib as a can into which an internal battery structure is inserted, wherein the lid and the wall rib or at least one has at least one wall rib. The present invention has been completed by finding that the above-described problem can be achieved by sandwiching the internal battery configuration between the pair of opposed wall surfaces, and has a positive electrode and a negative electrode including an active material capable of inserting and releasing lithium ions. In a non-aqueous secondary battery, a stacked body obtained by stacking a plurality of unit cells each formed by stacking a positive electrode plate and a negative electrode plate with a separator interposed therebetween or a wound body obtained by spirally winding the above-described single cell or the stacked body thereof is used. An opening is provided at one end, and further protrudes inward of at least one of a pair of opposing wall surfaces having a maximum area to form an outwardly exposed groove portion, preferably in a vertical and / or horizontal direction of the wall surface. One or more wall ribs extending from the end of one side to the end of the other side in the direction are provided in a box-shaped can with increased toughness, and the opening of the can is covered with a lid. The lid and the wall ribs or at least one of them has a wall rib.
The laminated body or the wound body is sandwiched between opposed wall surfaces. By providing the ribs on the wall surface of the can, the battery is less likely to be deformed even when thinned, and the laminate or the wound body is held at a predetermined position in the battery by sandwiching the laminate or the wound body. You.

[0006] Further, the wall rib is provided on the bottom wall of the can to serve as a bottom wall rib.
Forming a plurality of ribs extending outwardly from the end of one side to the end of the other side, preferably in the longitudinal and / or lateral direction, to form an outwardly exposed groove; And the laminated body or the wound body may be sandwiched between the lid rib and the bottom wall rib. By providing the lid with the ribs, the battery is less likely to be deformed, and the stacked body or the wound body is securely held.

The electric wire may be accommodated in a groove exposed outside the wall rib or the rib of the lid, and the groove may be used as a wiring space for the electric wire. By accommodating an electric wire in the groove, an extra space for wiring can be reduced.

Further, the wall ribs or the ribs of the lid are perpendicular to each other in the vertical and horizontal directions of the wall or the lid so as to extend from the end of one side to the end of the other side. May be provided.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> In a first embodiment according to the present invention, first, as shown in FIG. 1, a positive electrode plate 2 in which an electrode material layer is formed on the front and back surfaces of a rectangular metal foil having a predetermined width, respectively. The negative electrode plate 4 is
The positive electrode current collector 3 is laminated on the positive electrode plate 2, and the rearwardly extending positive electrode current collector 3 is laminated on the positive electrode plate 2. On the other hand, the belt-like piece 5 protrudes forward from the negative electrode plate 4 as a current collector. Then, each unit cell is formed (see FIG. 1A).

[0010] An insulating sheet 8 is wound around the stacked body 1 in which a plurality of unit cells are stacked except for the front and rear ends, and a plurality of strips 5 protruding from the front end are taken out through the insulating plate 7 while the rear. The positive electrode current collector 3 is taken out from the end, and a laminate A is manufactured (see FIG. 1B).

[0011] The laminate A is moved from the openings 12 to 11 on the upper surface.
The negative electrode current collector is bundled together and welded to the negative electrode terminal 18 provided on the lid 17 via the negative electrode connection conductor 9, and the positive electrode current collector is also bundled together via the positive electrode connection conductor 10. Can 11
(See FIG. 1C).

After storing the laminate A (see FIG. 1D), the can 1
The opening 12 on the upper surface of the container 1 is sealed with a lid 17, and the laminated body A is sandwiched between the lid 17 and the vertical ribs 15 and the horizontal ribs 16 on the bottom wall of the can 11, and then welded by laser (see FIG. 1E). ). FIG. 2 is a detailed cross-sectional view of the can 11 at a position closer to the side than the center of the can 11 at this time. Then, after injecting the non-aqueous electrolyte into the can 11 in a non-aqueous environment, the container is sealed and sealed (FIG. 1).
(Refer to FIG. 1F) and a completed product (see FIG. 1G).

Here, as the positive electrode material used as the positive electrode active material of the nonaqueous secondary battery of the first embodiment, any conventionally known materials can be used. For example, LixCoO ₂ , Lix
NiO ₂ , MnO ₂ , LiMnO ₂ , Li _x Mn ₂ O, Li _x
Mn _2-y O ₄ , α-V ₂ O ₅ , TiS _{2 and the} like.

As the negative electrode active material of the non-aqueous secondary battery of the first embodiment, graphite, calcined carbonaceous material, silicon, silicon compound and the like can be used.

As the non-aqueous electrolyte used in the non-aqueous secondary battery of the first embodiment, a non-aqueous electrolyte obtained by dissolving a lithium compound in an organic solvent can be used. The non-aqueous electrolyte is prepared by appropriately combining an organic solvent and an electrolyte, and any of these organic solvents and electrolytes can be used as long as they are used for this type of battery. Examples of the organic solvent include propylene carbonate, ethylene carbonate, vinylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, 1,2-dimethoxyethane, 1,2-diethoxyethane methylformate, butyrolactone, tetrahydrofuran and 2-methyl Tetrahydrofuran, 1-3 dioxofuran, 4-methyl-1,3-dioxofuran, diethyl ether, sulfolane, methylsulfolane, acetonitrile, propionitrile, butyronitrile, valeronitrile, benzonitrile, 1,2-dichloroethane, 4-methyl-2 -Pentanone, 1,4-dioxane, anisole, diglyme, dimethylformamide,
Dimethyl sulfoxide and the like. These solvents are
The species can be used alone or two or more can be used in combination. As the electrolyte, for example, LiCl
O ₄ , LiAsF ₆ , LiPF ₆ , LiBF ₄ , LiB (C
_{6 H 5) 4, LiCl,} LiBr, LiI, LiCH 3 SO
₃ , LiCF ₃ SO ₃ , LiAlCl _{4, and the} like. One of these can be used alone, or two or more can be used in combination.

Further, for the insulating packing in the non-aqueous secondary battery of the first embodiment, a fluorine resin material such as polytetrafluoroethylene can be used.

Further, as the separator in the nonaqueous secondary battery of the first embodiment, a porous insulating sheet such as porous polyethylene can be used.

In the non-aqueous secondary battery of the first embodiment, a metal such as aluminum, an aluminum alloy, and a stainless alloy can be used for the can and the lid.

The non-aqueous secondary battery of the first embodiment configured as described above uses a box-shaped can having an opening on the top and a rib on the bottom wall. Is not easily deformed, and the laminate is sandwiched between the lid and the bottom wall rib of the can, so that the laminate does not move and is held at a predetermined position in the battery even when subjected to a mechanical shock. Further, since the electric wires can be stored in the grooves exposed to the outside of the bottom wall ribs, it is possible to reduce an extra space for battery wiring.

<Second Embodiment> A non-aqueous secondary battery according to a second embodiment of the present invention is the same as the first embodiment except that a lid 17 is provided with a rib in the first embodiment, as shown in FIG. The configuration is the same as that of the first embodiment except for using. Even with the above configuration, the same effects as in the first embodiment can be obtained.

<Third Embodiment> A non-aqueous secondary battery according to a third embodiment of the present invention is, as shown in FIG.
A pair of side walls 33 and 34 are provided with side wall ribs 35 and 36, respectively, and the stacked body A is housed in the can 31 and then sealed with a lid 37. 36. A detailed cross-sectional view of the can 31 at a position closer to the side surface than the can 31 at this time is shown in FIG. 4B.

The non-aqueous secondary battery of the third embodiment configured as described above is provided with a box-shaped can having an opening at one end and a rib on the side wall, thereby providing the same configuration as that of the first embodiment. The effect is obtained.

In the first, second and third embodiments described above, the box-shaped can is configured as a positive electrode can. However, the present invention is not limited to this, and the box-shaped can is configured as a negative electrode can. May be.
Even with the above configuration, the same effects as those of the first, second, and third embodiments can be obtained.

[0024]

As described above, according to the embodiment of the present invention, an opening is provided at one end, and a rib is provided on at least one of a pair of opposed wall surfaces having a maximum area. By using a box-shaped can, toughness is imparted to the battery case, and the battery case is hardly deformed even when thinned.

Further, since the laminated body or the wound body is sandwiched between the lid and the bottom wall rib of the can or a pair of side wall ribs of the can facing each other, the laminated body inside the battery can be subjected to a mechanical shock. Alternatively, the wound body does not move, the possibility of poor electrical connection is reduced, and the reliability of the battery is increased.

Further, since the electric wire can be accommodated in the groove exposed to the outside of the rib, the wiring space can be reduced, and the size of the battery can be reduced.

[Brief description of the drawings]

FIG. 1 is a process chart showing the manufacture of a non-aqueous secondary battery according to first and second embodiments of the present invention.

FIG. 2 is a schematic longitudinal sectional view showing the internal structure of the non-aqueous secondary battery according to the first embodiment of the present invention.

FIG. 3 is a schematic longitudinal sectional view illustrating a configuration of a nonaqueous secondary battery according to a second embodiment of the present invention.

FIGS. 4A and 4B are a schematic perspective view and a schematic longitudinal sectional view showing a configuration of a non-aqueous secondary battery according to a third embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 1 laminated body, 2 positive electrode, 3 positive electrode current collector, 4 negative electrode, 5 negative electrode current collector, 6 separator, 7 insulating plate, 8 insulating sheet, 9 negative electrode current collector connection conductor, 10 positive electrode current collector connection conductor, 11 , 31 can, 12 can opening, 13, 33 can side wall, 14, 34 can bottom wall, 15 bottom wall vertical rib, 16 bottom wall horizontal rib, 17, 37 lid, 18, 38 negative electrode terminal, 19 , 39 insulating packing, 20 electrolyte injection port, 21, 41 safety valve, 35 side wall vertical rib, 36 side wall horizontal rib, A laminate 1 having insulating sheet 8 and insulating plate 7.

Claims (3)

[Claims] 1. A non-aqueous secondary battery having a positive electrode and a negative electrode containing an active material capable of inserting and releasing lithium ions, wherein a plurality of unit cells each comprising a positive electrode plate and a negative electrode plate laminated via a separator are laminated. The laminated body or the unit cell or the wound body obtained by spirally winding the laminated body is provided with an opening at one end, and further has a maximum area inside at least one of a pair of opposed wall surfaces. A box-like shape that has increased toughness by providing one or more wall ribs that protrude to form an outwardly exposed groove and extend from one side end to the other side end of the wall. It is stored in a can, and the opening of the can is sealed with a lid body in an insulated state.
A non-aqueous secondary battery characterized in that the laminated body or the wound body is sandwiched between the lid and a pair of opposed walls having at least one wall rib. 2. The lid according to claim 1, wherein the wall rib is a bottom wall rib, and the lid has a groove protruding inwardly and outwardly formed in the lid and extending from one end of the lid to the other. A plurality of ribs extending so as to reach an end of the side surface of the slab are provided to enhance toughness, and the laminated body or the wound body is sandwiched between the lid rib and the bottom wall rib. 2. The non-aqueous secondary battery according to 1. 3. The wire according to claim 1, wherein an electric wire is accommodated in a groove exposed outside the wall rib or the lid rib, and the groove is used as a wiring space for the electric wire. Non-aqueous secondary battery.