JP2003077447A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery in which steady insulation can be obtained by winding a sheet of outer insulation sheet 8 at least covering only the outside of the lead part 4c and slippage that happens between the conventional two sheets of outer insulation sheets 9, 10 can be eliminated. SOLUTION: The battery comprises a winding type generating element 2 and the negative electrode is connected to the negative electrode terminal 5 through a negative electrode current-collector connecting plate 3 on the upper end side of this generating element 2, and the positive electrode is connected to a positive electrode current-collector connecting plate 4 on the lower end side of this generating element 2, and the lead part 4c of this positive electrode current-collector connecting plate 4 is drawn out along the outer periphery side of the generating element 2 up to the upper top end side and connected to the positive electrode terminal 6. An outer insulation sheet 8 is wound only one and a half round on the outer periphery of the generating element 2 and the outer periphery of the outside of the lead part 4c of the positive electrode current-collector connecting plate 4, and the outside of this lead part 4c is covered folding twofold by this outer insulation sheet 8, and the winding finishing part is fastened by an adhesive tape 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery insulating structure having a winding type power generating element.

[0002]

2. Description of the Related Art FIG. 2 shows an example of a conventional structure of a long cylindrical wound type non-aqueous electrolyte secondary battery. In this non-aqueous electrolyte secondary battery, a long cylindrical winding-type power generation element 2 is housed inside a long cylindrical container-shaped battery can 1. The power generation element 2 is formed by winding a positive electrode and a negative electrode into a long cylindrical shape via a separator, and a separator is provided on the outermost circumference so as to further cover the winding end portion of the negative electrode wound so as to cover the positive electrode. It is wound extra. Further, in the power generating element 2, the positive electrode and the negative electrode are vertically displaced during winding, so that the upper end edge portion of the wound negative electrode projects on the upper end surface and the lower end of the wound positive electrode on the lower end surface. The negative electrode is connected to the negative electrode current collecting and connecting plate 3 arranged on the upper end surface side of the power generating element 2, and the positive electrode is connected to the lower end surface side of the power generating element 2 so that the edge portion protrudes. It is connected to the positive electrode current collector connection plate 4. In the figure, in order to make the configuration of the power generation element 2 easy to understand, the number of windings of the electrodes is reduced. This also applies to the following drawings.

The negative electrode current collecting and connecting plate 3 has a corrugated plate-like negative electrode connecting portion 3a arranged on one side of a central straight line portion on the elliptical upper end surface of the power generating element 2 and one of the elliptical upper end surface. A negative electrode terminal connecting portion 3b in the shape of a semi-circular flat plate disposed above the curved portion, and a negative electrode terminal connecting portion 3b via a plate piece that is obliquely drawn upward from one end of the negative electrode connecting portion 3a toward the curved portion. It is integrally connected with. The negative electrode collector connection plate 3 is fixed by ultrasonic welding, laser welding, caulking, or the like by sandwiching the upper edge of the negative electrode protruding from the upper end surface of the power generation element 2 in the corrugated plate-shaped recess of the negative electrode connecting portion 3a. By doing so, the connection is fixed. Further, the lower end portion of the negative electrode terminal 5 is connected and fixed by caulking or the like to the flat center portion of the negative electrode terminal connecting portion 3b.

The positive electrode current collecting and connecting plate 4 has a corrugated plate-like positive electrode connecting portion 4a arranged on one side of a central straight line portion on the lower end surface of the elliptical shape of the power generating element 2 and the elliptic shape of the power generating element 2. A semi-circular flat plate-shaped positive electrode terminal connecting portion 4b arranged above the other curved portion of the end surface, and a positive electrode terminal connecting portion that is pulled out from one end side of the positive electrode connecting portion 4a to the upper end surface along the outer peripheral side surface of the power generating element 2. 4b and the lead portion 4c integrally connected to the 4b. The positive electrode current collector / connector plate 4 has a positive electrode connecting portion 4a formed by connecting the lower end edge portion of the positive electrode protruding to the lower end surface of the power generating element 2.
It is connected and fixed by being sandwiched in the corrugated plate-shaped recess and fixed by ultrasonic welding, laser welding, caulking, or the like. Further, the lower end portion of the positive electrode terminal 6 is connected and fixed to the central portion of the positive electrode terminal connecting portion 4b having a flat plate shape by caulking or the like. The positive electrode current collector / connection plate 4 is thus the power generation element 2
The positive electrode connecting portion 4a connected to the positive electrode on the lower end surface of the lead portion 4
The positive electrode terminal 6 and the negative electrode terminal 5 can be arranged side by side on the upper end surface side of the power generating element 2 by drawing out to the positive electrode terminal connecting portion 4b on the upper end surface via c.

An oblong plate-like cover plate (not shown) is fitted into the upper end opening of the battery can 1 accommodating the power generating element 2 and fixed by welding. In addition, the lid plate penetrates through the upper ends of the negative electrode terminal 5 and the positive electrode terminal 6 in both elliptic curved portions and is fixed by insulation and sealing.

However, since the lead portion 4c of the positive electrode current collecting and connecting plate 4 is arranged between the outer peripheral side surface of the power generating element 2 and the inner peripheral side surface of the battery can 1, the electrode of the power generating element 2 and the battery can are formed. It is necessary to surely insulate between 1 and 1. Therefore, in the conventional non-aqueous electrolyte secondary battery, as shown in FIG. 3, the inner insulating sheet 7 is arranged at the outermost periphery of the power generating element 2, and the positive electrode current collector / connector plate 4 is provided outside the inner insulating sheet 7. Lead portion 4c is arranged, and the first outer insulating sheet 9 and the second outer insulating sheet 10 are overlapped by one or more turns so as to cover the outer peripheral surface of the inner insulating sheet 7 and the outer surface of the lead portion 4c. It was wound around. Note that, in FIG. 3, the inner and outer insulating sheets 7, 9, 10 and the positive electrode current collector / connection plate 4 are virtually shown in a state immediately before attachment in order to clarify the positional relationship between them.

These inner and outer insulating sheets 7, 9 and 10 are
All are hard and durable resin sheets made of polyimide. Then, the inner insulating sheet 7 is wound around the outermost circumference of the power generation element 2 so as to slightly exceed one turn, and then the adhesive tape 11 that sticks out and is attached to the winding terminal end is applied to the outer peripheral surface of the winding start end. It is fixed by adhesion. Further, the winding start end of the inner insulating sheet 7 is the power generation element 2
It is also possible to adhere it to the winding end of the outermost separator by using an adhesive tape. Therefore, the inner insulating sheet 7 can prevent the electrode from coming into contact with the lead portion 4c through the soft and weak separator wound around the outermost periphery of the power generating element 2. The first outer insulating sheet 9 is wound so as to cover the entire outer peripheral side surface of the power generating element 2 including the outer side surface of the lead portion 4c to slightly exceed one turn, and then is attached to the winding terminal end portion by sticking out. The tape 11 is fixed by adhering it to the outer peripheral surface of the winding start end. Therefore, the first outer insulating sheet 9 can prevent the lead portion 4c from coming into contact with the inner peripheral side surface of the battery can 1.

However, with only the first outer insulating sheet 9, there is some anxiety about the insulation between the lead portion 4c and the inner peripheral side surface of the battery can 1. Because the lead portion 4c is a pressed metal plate, there is an edge at the end,
If this is covered with the first outer insulating sheet 9 only once,
This is because when the edge damages the resin sheet, the risk of contacting the inner peripheral side surface of the battery can 1 through the damage cannot be eliminated without fail. For this reason, in the conventional nonaqueous electrolyte secondary battery, the second outer insulating sheet 10 is doubly wound so as to overlap the first outer insulating sheet 9 as described above. The second outer insulating sheet 10 is
The entire outer circumference of the first outer insulating sheet 9 is wound to slightly exceed one round, and then the adhesive tape 11 protruding and attached to the winding end is adhered to the outer peripheral surface of the winding start to fix it. ing. Therefore, the first outer insulating sheet 9 and the second outer insulating sheet 10 doubly cover the outer surface of the lead portion 4c, so that the lead portion 4c is attached to the battery can 1
It is possible to reliably prevent contact with the inner peripheral side surface of the.

[0009]

However, in the conventional non-aqueous electrolyte secondary battery described above, the two first non-aqueous electrolyte secondary batteries are provided outside the power generation element 2.
Since the outer insulating sheet 9 and the second outer insulating sheet 10 are wound, not only the number of work steps for winding them increases but also it is necessary to prepare many outer insulating sheets 9 and 10 and adhesive tape 11 as parts. There was a problem that there was. Further, when the outer side of the power generation element 2 is covered with the two first outer insulating sheets 9 and the second outer insulating sheet 10 in this way, these outer insulating sheets 9 and 10 are slippery, When the outer peripheral side surface of the power generation element 2 is gripped and lifted, the heavy weight of the power generation element 2 causes a gap between the second outer insulating sheet 10 and the first outer insulating sheet 9, and When inserting into the battery can 1,
There is also a problem that the second outer insulating sheet 10 may be caught in the edge of the upper end opening of the battery can 1 and may be stored in a state in which the second outer insulating sheet 9 is displaced from the first outer insulating sheet 9.

The present invention has been made in order to cope with such a circumstance, and a single insulating sheet is overlapped and wound only at least on the outer side of the lead portion to obtain reliable insulation and the insulating sheet. It is an object of the present invention to provide a battery that can eliminate the deviation.

[0011]

According to a first aspect of the present invention, there is provided a wound-type power generating element, and one of positive and negative electrodes is provided on one end surface side of the power generating element through a first current collector connector. In addition to connecting to the terminal, the other electrode is connected to the second current collecting connector on the other end face side of the power generating element, and the lead portion of the second current collecting connector is connected to the one end face along the outer peripheral side surface of the power generating element. In the battery connected to the second terminal by being pulled out to the side, an insulating sheet is wound around the outer peripheral side surface of the power generating element and the outer peripheral surface of the outer side surface of the lead portion of the second current collector connector, and at least the outer side of the lead portion is covered with this insulating sheet. It is characterized in that it is overlapped with two or more layers to cover the end of the winding.

According to the first aspect of the present invention, since the insulating sheet is wound around the outer periphery of the lead portion of the second current collector in a double or more layered manner, the edge of the lead portion is the most part of the insulating sheet. Even if the inner peripheral side is damaged, the insulating sheet on the outer peripheral side covers the inner peripheral side, so that the inner peripheral surface of the battery container accommodating the power generating element can be reliably insulated. Moreover,
Since only one insulating sheet is wound around the outer periphery of the power generation element, the number of parts such as this insulating sheet and adhesive tape is increased or the work process is increased as in the conventional example in which two insulating sheets are wound. There is nothing to do. In addition, when the outer peripheral side surface of the power generating element is gripped, or when the power generating element is housed in a battery container, it is possible to eliminate the gap between the insulating sheets as in the conventional example in which two insulating sheets are wound. become able to.

According to a second aspect of the present invention, the number of the insulating sheets is one, and the outer peripheral surface of the power generation element and the outer peripheral surface of the outer surface of the lead portion of the second current collector are wound more than one turn and less than two turns. Characterized by turning.

According to the second aspect of the present invention, since one insulating sheet is wound for about one and a half turns, the outer circumference of the lead portion is surely double-wound, but the outer circumference of the power generating element. Most of the other part of the outer circumference of the side surface is wound only once, and the insulating sheets are not unnecessarily overlapped and wound. Moreover, if the insulating sheet is wound more than two times, there is a possibility that misalignment may occur between the windings, but since it is the minimum necessary winding, there is a concern that such misalignment may occur. Disappear.

According to a third aspect of the present invention, an inner insulating sheet having a size larger than at least an area in which they are in contact is disposed between the outermost periphery of the power generating element and the second current collecting connector, and the outer peripheral surface of the inner insulating sheet is arranged. It is characterized in that the lead portion of the second current collector connector is arranged along the line.

According to the third aspect of the invention, since the inner insulating sheet is arranged between the power generating element and the lead portion, the insulation between the electrode of the power generating element and the lead portion can be ensured. be able to. The inner insulating sheet is made of, for example, the same material as the insulating sheet wound around the outer periphery, and is formed directly on the outer periphery of the separator by using a dense and durable resin sheet different from the separator of the power generation element. Insulation can be enhanced more than when the lead portion is arranged.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, and FIG. 1 is an assembled perspective view of a power generation element in which an outer insulating sheet is wound around an outer periphery. The constituent elements having the same functions as those of the conventional example shown in FIGS.

In this embodiment, as in the conventional example shown in FIG. 2, a long cylindrical wound type non-aqueous electrolyte secondary battery will be described. The power generation element 2 of this non-aqueous electrolyte secondary battery is shown in FIG.
As shown in FIG. 5, the negative electrode connecting portion 3a of the negative electrode current collector / connector plate 3 is connected and fixed to the upper edge portion of the negative electrode protruding from the upper end surface of the oblong cylinder. Further, in FIG. 1, the inner insulating sheet 7
The positive electrode current collector connection plate 4 is virtually shown in a state immediately before attachment in order to clarify the positional relationship between them.

In the power generating element 2, the separator is additionally wound so as to further cover the winding end portion of the negative electrode wound so as to cover the positive electrode on the outermost circumference, and the outer peripheral side surface is completely covered. The inner insulating sheet 7 is wound about one round so as to cover the outermost separator of the power generating element 2. Similar to the conventional example, the inner insulating sheet 7 is fixed by adhering an adhesive tape 11 protruding and attached to the winding end portion to the outer peripheral surface of the winding start end portion. When the negative electrode current collector connection plate 3 and the positive electrode current collector connection plate 4 are connected and fixed to the negative electrode and the positive electrode of the power generation element 2 whose outermost periphery is covered with the inner insulating sheet 7 as described above, the positive electrode current collector connection plate 4 is used. Lead part 4c
Are arranged along the outer peripheral surface of the inner insulating sheet 7. In addition,
Since the inner insulating sheet 7 may insulate the power generating element 2 and the positive electrode current collector / connector plate 4 from each other, it is sufficient to dispose a sheet having an area larger than at least the area where they are in contact with each other, and the winding is not limited to one or more turns. No need.

In the power generating element 2 to which the current collecting and connecting plates 3 and 4 are connected and fixed as described above, the outer insulating sheet 8 is wound around the outer peripheral side surface and the outer peripheral surface of the outer surface of the lead portion 4c. The outer insulating sheet 8 is wound around the outer peripheral side surface of the power generation element 2 once and a half. At this time, the outer insulating sheet 8 is a positive electrode in which a winding start end portion and a winding end portion in one and a half turns are double overlapped over a half circumference and are arranged along the outer peripheral side surface of the power generation element 2. It is wound so as to completely cover the outside of the lead portion 4c of the collector connection plate 4. After winding, the outer insulating sheet 8 is fixed by sticking an adhesive tape 11 that sticks out to the winding end portion and is attached to the outer peripheral surface of the winding start end portion. The outer insulating sheet 8 is adhered to the outer peripheral surface of the outermost inner insulating sheet 7 of the power generating element 2 by attaching another adhesive tape that sticks out to the winding start end portion and is attached thereto. It is possible to prevent misalignment between the insulating sheet 7 and the outer insulating sheet 8. In addition, in FIG. 1, the outer insulating sheet 8 is also shown in a virtual state immediately before attachment in order to clarify the positional relationship.

The inner insulating sheet 7 used here is a hard and durable resin sheet made of the same polyimide as shown in the conventional example, and the outer insulating sheet 8 can also be made of the same material. However, the inner insulating sheet 7 and the outer insulating sheet 8 may be made of other materials as long as they have sufficient insulating properties and strength and have corrosion resistance and heat resistance to the electrolytic solution. . Further, as the adhesive tape 11, a sheet of the same material having a pressure-sensitive adhesive applied to one surface is used. However, in addition to using such an adhesive tape 11, the inner insulating sheet 7 and the outer insulating sheet 8 are coated with an adhesive on the inner side surface of the end portion of the outer insulating sheet 8 to be adhered, or by heat welding. It can be fixed by any means such as welding the parts together.

The power generating element 2 wound with the outer insulating sheet 8 as described above is inserted from the upper end opening of the battery can 1 shown in FIG. When the power generating element 2 is housed in the battery can 1, the lid plate is fitted into the upper end opening of the battery can 1 and welded.

According to the non-aqueous electrolyte secondary battery having the above structure,
Since the inner insulating sheet 7 is arranged on the inner peripheral side of the lead portion 4c of the positive electrode current collector / connector plate 4 as in the conventional case, the power generating element 2
It is possible to ensure the insulation between the electrodes.

Further, the lead portion 4 of the positive electrode current collector connection plate 4
Since the outer insulating sheet 8 is wound around the outer periphery of c so as to be doubled, the insulation between the outer peripheral surface of the battery can 1 and the inner peripheral side surface of the battery can 1 can be ensured. Since the lead portion 4c is a metal plate made of aluminum or the like formed by sheet metal working, the edge or the like may damage the outer insulating sheet 8. However, according to the present embodiment, the lead portion 4c
Even if the winding start end of the outer insulating sheet 8 that is directly in contact with the edge is damaged by the edge, the winding end of the outer insulating sheet 8 that is arranged so as to overlap the outer periphery of the outer insulating sheet 8 is between the inner peripheral side surface of the battery can 1. Since it is interposed, it is possible to reliably prevent the lead portion 4c from coming into contact with the inner peripheral side surface of the battery can 1.

Moreover, since only one outer insulating sheet 8 is wound around the outer periphery of the power generating element 2, two outer insulating sheets 9 and 10 are wound and fixed with the adhesive tape 11 as in the conventional case. The labor of such work is reduced, and the use of the outer second outer insulating sheet 10 and the adhesive tape 11 for fixing the second outer insulating sheet 10 can be omitted.
Furthermore, when two outer insulating sheets 9 and 10 are wound around the outer periphery of the power generating element 2 as in the conventional case, the power generating element 2
When the outer peripheral side surface is gripped by a hand or a transport jig to store the battery in the battery can 1, only the heavy power generating element 2 tries to fall downward, resulting in displacement between the outer insulating sheets 9 and 10. However, when the power generating element 2 is stored in the battery can 1, the second outer insulating sheet 10 may be caught at the edge of the upper end opening portion and may be displaced from the first outer insulating sheet 9. One outer insulation sheet 8 like
If only is wound, it becomes possible to eliminate such a deviation. Further, if the winding start end portion of the outer insulating sheet 8 is adhered to the outermost inner insulating sheet 7 of the power generating element 2 with an adhesive tape or the like, it is possible to almost eliminate a gap between them.

Further, in this embodiment, the outer insulating sheet 8 is used.
Since only one and a half rounds are wound around the lead portion 4c, the outer circumference of the lead portion 4c is surely double-wound, but most of the other portion is only wound once. It is also possible to prevent winding deviation of 8 due to redundant winding.

In the above embodiment, the case where the outer insulating sheet 8 is wound around the outer periphery of the power generating element 2 for one and a half rounds has been described, but the number of windings exceeds one round and the winding start end and the winding end end. It is not always necessary to wind up to one and a half rounds as long as the overlapped portion of (1) surely covers the outside of the lead portion 4c. However, since it is sufficient that at least the outer side of the lead portion 4c is double-overlapped and covered, it is possible to wind any number of times exceeding one and a half turns. That is, for example, by winding two and a half turns, the outer insulating sheet 8 can be triple-layered on the outer side of the lead portion 4c.

In the above embodiment, the case where the inner insulating sheet 7 is wound inside the lead portion 4c of the positive electrode current collector / connector plate 4 has been described. However, for example, a separator wound around the outermost periphery of the power generating element 2 may be used. If sufficient insulation can be obtained, the inner insulating sheet 7 may be omitted. However, the insulation between the negative electrode protruding on the upper end surface of the power generation element 2 and the positive electrode current collector connection plate 4 must be surely performed regardless of the presence or absence of the inner insulating sheet 7.

Further, in the above-described embodiment, the case where the lead portion 4c is provided on the positive electrode current collector connection plate 4 connected to the positive electrode of the power generation element 2 has been described. The same can be done when the element 2 is configured to be drawn out along the outer peripheral side surface. Furthermore, in the above-described embodiment, the case where the power generation element 2 has a long cylindrical shape has been described, but the same can be applied to a winding type power generation element 2 having another shape such as a cylindrical shape. For example, in the case of a cylindrical power generation element 2, the lead portion 4c of the positive electrode current collector / connection plate 4
Is a metal plate curved along the cylindrical outer peripheral side surface of the power generating element 2. Further, in the above-described embodiment, the non-aqueous electrolyte secondary battery in which the power generation element 2 is housed in the battery can 1 and covered with the lid plate has been described, but the configuration of the battery container housing the power generation element 2 is arbitrary. Furthermore, although the non-aqueous electrolyte secondary battery has been described in the above embodiment, other types of batteries can be similarly implemented.

[0031]

As is apparent from the above description, according to the battery of the present invention, since the insulating sheets are wound around the outer periphery of the lead portion of the second current collector in double or more layers, the power generation is improved. Insulation can be ensured from the inner surface of the battery container accommodating the element. Moreover, since only one insulating sheet is wound around the outer periphery of the power generation element, the number of parts and the work process do not increase. Further, it becomes possible to grasp the outer peripheral side surface of the power generation element and eliminate the displacement of the insulating sheet that occurs when the power generation element is housed in the battery container.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, and is an assembled perspective view of a power generation element in which an outer insulating sheet is wound around an outer periphery.

FIG. 2 is an assembled perspective view showing the internal structure of a non-aqueous electrolyte secondary battery.

FIG. 3 is a perspective view showing a conventional example and is an assembled perspective view of a power generation element in which a first outer insulating sheet and a second outer insulating sheet are wound around an outer periphery.

[Explanation of symbols]

2 power generation elements 3 Negative electrode current collector connection plate 3a Negative electrode connection part 3b Negative electrode terminal connection part 4 Positive current collector connection plate 4a Positive connection part 4b Positive terminal connection part 4c lead part 5 Negative electrode terminal 6 Positive terminal 7 Inside insulation sheet 8 Outside insulation sheet 11 Adhesive tape

Claims (3)

[Claims] 1. A winding type power generating element, wherein either positive or negative electrode is connected to a first terminal on one end face side of the power generating element via a first current collector connector, and the other electrode is used for power generation. A battery in which the other end face side of the element is connected to the second current collector connector, and the lead portion of the second current collector connector is pulled out to one end face side along the outer peripheral side surface of the power generating element and connected to the second terminal. In, an insulating sheet is wound around the outer peripheral side surface of the power generating element and the outer peripheral surface of the outer side surface of the lead portion of the second current collector connector, and at least the outer side of the lead portion is covered with the insulating sheet in a double or more overlapping manner.
A battery characterized in that the winding end portion is fixed. 2. The number of the insulating sheets is one, and the outer peripheral surface of the power generating element and the outer peripheral surface of the outer surface of the lead portion of the second current collector are wound more than one turn and less than two turns. The battery according to claim 1, wherein 3. An inner insulating sheet having a size larger than at least the area in which they are in contact is arranged between the outermost periphery of the power generating element and the second current collector / connector, and a second inner sheet is formed along the outer peripheral surface of the inner insulating sheet. The battery according to claim 1 or 2, wherein the lead portion of the current collector connector is arranged.