JP3015663U - Spiral lithium battery - Google Patents

Abstract

(57) [Summary] [Purpose] By increasing the output of spiral lithium batteries,
Enables compatibility with high current load applications. [Structure] On one end side of the strip-shaped positive electrode 3 in the width direction, the positive electrode 3
Two or three positive electrode lead plates 7 are attached at positions corresponding to approximately equal points in the length direction of the positive electrode 3 at the same phase. The strip-shaped negative electrode 5 is separated from the positive electrode 3 via the separator 6 and spirally wound to form the electrode group 2. The electrode group 2 is inserted into the negative electrode can, and the tip of each positive electrode lead plate 7 is fixed to the positive electrode terminal. The positive electrode terminal portion is fitted into the opening portion of the negative electrode can via a sealing gasket to form a spiral lithium battery. [Effect] Since each positive electrode lead plate 7 is attached at a position corresponding to an approximately equal point in the length direction of the positive electrode 3, the positive electrode 3 is lengthened to increase the distance to the positive electrode lead plate 7. Instead, the current density per unit area can be reduced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a high output spiral lithium battery that can be used for a large current load.

[0002]

[Prior art]

 FIG. 4 is a diagram showing an example of an electrode group constituting a conventional spiral lithium battery, (a) is a perspective view and (b) is a developed view of its positive electrode.

As shown in FIG. 4A, a conventional spiral lithium battery has an electrode group 2 in which a strip-shaped positive electrode 3 and a strip-shaped negative electrode 5 are spirally wound via a separator 6. As shown in FIG. 4 (b), the positive electrode lead attached to the positive electrode lead 3 attached to the positive electrode 3 at a substantially central position in the longitudinal direction (left / right direction of FIG. 4 (b)) is taken out from the electrode group 2. This is done through the plate 7.

Here, in order to increase the output of the spiral lithium battery, usually, the area of the electrodes (the positive electrode 3 and the negative electrode 5) is increased to reduce the current density per unit area. Since the dimension in the height direction, that is, the width direction of the electrode is limited by product standards, etc., in actuality, the length of the electrode is increased to achieve higher output. At this time, in order to keep the volume of the electrode group 2 constant, the thickness of the electrode becomes thin corresponding to its length.

[0005]

[Problems to be solved by the device]

 However, in addition to the electric resistance of the positive electrode 3 being larger than that of the negative electrode 5 at a certain constant interval of the electrodes, if the positive electrode 3 is lengthened in order to increase the output, the theoretical current density per unit area is reduced. Since the distance to the positive electrode lead plate 7 becomes large (that is, the electric resistance becomes large), the effect of increasing the area of the electrode is offset, so that the effect of increasing the output does not reach the limit even if the electrode is made too long. Becomes For example, according to the experiments by the present inventors, the length 30 cm of the positive electrode 3 of the AA battery is taken as a reference, and this is 1.5 times (45 cm), 2.0 times (60 cm), 2.5 times ( Higher output could be realized by increasing the size to 75 cm), but the effect was almost unchanged at 2.0 times or more.

In view of the above circumstances, an object of the present invention is to provide a spiral lithium battery that realizes a significantly high output.

[0007]

[Means for Solving the Problems]

 That is, the spiral lithium battery (1) according to the present invention is located on one end side in the width direction of the strip-shaped positive electrode (3) at a position corresponding to a substantially equal point in the longitudinal direction of the positive electrode (3). Attach two or three positive electrode lead plates (7) at the same phase position, separate the strip-shaped negative electrode (5) from the above positive electrode through the separator (6), and wind these positive electrode, negative electrode and separator in a spiral shape. The electrode group (2) by winding the electrode group into the negative electrode can (9), fixing the tip of each positive electrode lead plate to the positive electrode terminal portion (12), and sealing the positive electrode terminal portion. The negative electrode can is fitted in the opening through a gasket (10).

The numbers in parentheses are for convenience of showing corresponding elements in the drawings, and the present invention is not limited to the description in the drawings. The same applies to the "Claims for utility model registration" and "Action" columns.

[0009]

[Action]

 With the above-described structure, in the present invention, since each positive electrode lead plate (7) is attached to the positive electrode (3) at a position corresponding to an approximately equal point in the longitudinal direction, the positive electrode is lengthened to increase the positive electrode. It works so that the current density per unit area can be reduced without increasing the distance to the lead plate.

Further, in the present invention, since all the positive electrode lead plates (7) are attached at the same phase position on the positive electrode (3), the tips of the positive electrode lead plates can be easily attached to the positive electrode terminal portion (12). It acts so as to be fixed to the.

[0011]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. 1 is a sectional view showing an embodiment of a spiral lithium battery according to the present invention, FIG. 2 is a view showing an electrode group constituting the spiral lithium battery shown in FIG. 1, (a) is a perspective view, b) is a development view of the positive electrode, and FIG. 3 is a graph showing discharge characteristics of the spiral lithium battery.

As shown in FIG. 1, the spiral lithium battery 1 according to the present invention has a cylindrical negative electrode can 9 to which an exterior film 8 is attached. An electrode group 2 composed of the negative electrode 5 and the separator 6 is inserted via an insulating bottom plate 11. Further, the negative electrode can 9 is impregnated with an electrolytic solution, and the positive electrode terminal portion 12 is fitted into the opening of the negative electrode can 9 through an insulating sealing gasket 10. Further, two positive electrode lead plates 7 are provided between the positive electrode 3 of the electrode group 2 and the positive electrode terminal portion 12 so as to electrically connect the two, and the negative electrode 5 of the electrode group 2 is the negative electrode lead. It is electrically connected to the negative electrode can 9 through a plate (not shown).

When manufacturing the spiral lithium battery 1 according to the present invention, the following procedure is performed.

That is, first, the electrode group 2 with the two positive electrode lead plates 7 is manufactured. To this end, as shown in FIG. 2B, first, on one end side in the width direction of the strip-shaped positive electrode 3 (upper side in FIG. 2B), the lengthwise direction of the positive electrode 3 (left-right direction in FIG. 2B) is set. 2) The two positive electrode lead plates 7 are attached at the positions corresponding to the approximate trisecting points in the above) and the same phase position on the positive electrode 3. Here, the “in-phase position” means that, after winding the positive electrode 3 and the like, which will be described later, as shown in FIG. 2A, two positive electrode lead plates 7 extend from the center of the spiral positive electrode 3 to the outer peripheral side. It means a position where they are arranged substantially on the same line in the radial direction. Next, as shown in FIG. 2A, the strip-shaped positive electrode 3 is separated from the strip-shaped negative electrode 5 via a separator 6, and the positive electrode 3, the negative electrode 5 and the separator 6 are spirally wound to form an electrode group 2. And

In this way, when the electrode group 2 with the two positive electrode lead plates 7 is produced, the bottom plate 11 is fitted to the bottom of the electrode group 2 and inserted into the negative electrode can 9, and then the two positive electrodes are inserted. The leading end portions of the lead plates 7 are overlapped with each other and spot-welded and fixed to the positive electrode terminal portion 12. Next, after injecting the electrolytic solution into the negative electrode can 9, the positive electrode terminal portion 12 is placed on the beading portion of the negative electrode can 9 through the sealing gasket 10, and the opening of the negative electrode can 9 is caulked in this state. Seal. Finally, the exterior film 8 is attached to the outer peripheral surface of the negative electrode can 9 to complete the spiral lithium battery 1.

In the spiral lithium battery 1 manufactured in this way, as described above, the two positive electrode lead plates 7 are attached to the positive electrode 3 at positions corresponding to approximately three equal points in the longitudinal direction. By lengthening the positive electrode 3 (with this, the negative electrode 5 and the separator 6 are also lengthened), the current density per unit area can be reduced without increasing the distance to the positive electrode lead plate 7. As a result, it is possible to significantly increase the output.

In order to confirm the above effect, the discharge performance of the present invention product and the conventional product (spiral type lithium battery having an electrode group in which one positive electrode lead plate is attached at substantially the center in the length direction of the positive electrode) The test was conducted. The test was conducted under the temperature condition of -20 ° C. Repeated load of 9A, 0.44s / 0.14A, 49.56s was applied. The results are shown graphically in FIG. The graph of FIG. 3 shows a voltage curve under a load of 1.9A. In FIG. 3, ~ is a conventional product and ~ is a product of the present invention, and the lengths of the positive electrode are and are 30 cm, 45 cm, 60 cm, and 75 cm. As is clear from FIG. 3, as the positive electrode becomes longer, the conventional product has reached the limit of high output at about 60 cm, whereas the product of the present invention exceeds 60 cm to 75 cm. It can be seen that the output is even higher.

Further, since the two positive electrode lead plates 7 are attached at the same phase position on the positive electrode 3, as described above, the tips of the positive electrode lead plates 7 are overlapped and spotted on the positive electrode terminal portion 12. Since it can be welded, the productivity will not be lower than that of the conventional spiral lithium battery that uses only one positive electrode lead plate.

Although the spiral lithium battery 1 having the electrode group 2 in which the two positive electrode lead plates 7 are attached to the strip-shaped positive electrode 3 has been described in the above embodiment, the positive electrode lead plate 7 has The number is not limited to two, and may be any number as long as it is two or more. However, if the number of the positive electrode lead plates 7 is too large, it becomes difficult to determine the in-phase position on the positive electrode 3 so that all the positive electrode lead plates 7 are arranged substantially in the same line. A suitable number of the plates 7 is 2-3. In addition, when the three positive electrode lead plates 7 are attached to the strip-shaped positive electrode 3, the attachment positions thereof are positions corresponding to approximately quadrants in the length direction of the positive electrode 3 on the positive electrode 3. It goes without saying that they are in the same phase position of.

[0020]

[Effect of device]

 As described above, according to the present invention, on one end side in the width direction of the strip-shaped positive electrode 3, the same phase on the positive electrode 3 is located at a position corresponding to a substantially equal point in the length direction of the positive electrode 3. Two or three positive electrode lead plates 7 are attached at the positions, the strip-shaped negative electrode 5 is isolated from the positive electrode 3 via the separator 6, and the positive electrode 3, the negative electrode 5 and the separator 6 are spirally wound to form an electrode group 2. Then, the electrode group 2 is inserted into the negative electrode can 9, the tip of each positive electrode lead plate 7 is fixed to the positive electrode terminal portion 12, and the positive electrode terminal portion 12 is inserted through the sealing gasket 10. Since the positive electrode lead plates 7 are attached to the openings of the positive electrode 3, the positive electrode lead plates 7 are attached to the positive electrode 3 at positions corresponding to substantially equal dividing points in the longitudinal direction. , Without increasing the distance to the positive electrode lead plate 7, Since it is possible to reduce the current density per area, it is possible to considerably higher output spa Iraru type lithium battery 1, it is possible to respond to a large current load applications.

Further, since all the positive electrode lead plates 7 are attached at the same phase position on the positive electrode 3, the tips of the positive electrode lead plates 7 are easily fixed to the positive electrode terminal portion 12, so Even if the number of plates 7 increases, the productivity does not decrease.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a spiral lithium battery according to the present invention.

2A and 2B are diagrams showing an electrode group constituting the spiral lithium battery shown in FIG. 1, in which FIG. 2A is a perspective view and FIG. 2B is a development view of the positive electrode.

FIG. 3 is a graph showing discharge characteristics of a spiral lithium battery.

4A and 4B are diagrams showing an example of an electrode group constituting a conventional spiral lithium battery, in which FIG. 4A is a perspective view and FIG. 4B is a developed view of the positive electrode.

[Explanation of symbols]

 2 ... Electrode group 3 ... Positive electrode 5 ... Negative electrode 6 ... Separator 7 ... Positive electrode lead plate 9 ... Negative electrode can 10 ... Seal gasket 12 ... Positive electrode terminal portion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroyuki Nakata 5 36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Chemical Co., Ltd. (72) Inventor Shuichi Arae 5 36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Kagaku Co., Ltd. (72) Inventor Masatake Nishio 5-36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Kagaku Co., Ltd. (72) Akihide Izumi 5-36-11 Shinbashi, Minato-ku, Tokyo Fuji Electrochemical Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A strip-shaped positive electrode (3) is provided on one end side in the width direction,
Two or three positive electrode lead plates (7) are attached at positions corresponding to approximately equal points in the length direction of the positive electrode and in the same phase position on the positive electrode, and the strip-shaped negative electrode (5) is attached to the positive electrode. The positive electrode, the negative electrode, and the separator are separated by a separator (6), and the positive electrode, the negative electrode, and the separator are spirally wound to form an electrode group (2), and the electrode group is inserted into a negative electrode can (9). A spiral lithium battery having a tip portion fixed to a positive electrode terminal portion (12), and the positive electrode terminal portion being fitted into an opening portion of the negative electrode can via a sealing gasket (10).