KR20050081707A - The laminated cell with the outmost electrode and the lead of the opposite electrode thereof separated by the insulating material - Google Patents

Abstract

The present invention provides a stacked battery in which an insulating material is applied or taped to a bent portion of a lead of an opposite electrode that can be in physical contact with the outermost electrode, or an insulating material is inserted between the lead of the outermost electrode and the opposite electrode.

The present invention can prevent a short between the positive electrode and the negative electrode which may occur in a battery having a laminated structure.

Description

FIELD OF THE ELECTRODE AND THE LEAD OF THE OPPOSITE ELECTRODE THEREOF SEPARATED BY THE INSULATING MATERIAL}

The present invention relates to a stacked battery in which an insulating material is applied or taped to a bent portion of a lead of an opposite electrode which can be in physical contact with the outermost electrode, or an insulating material is inserted between the lead of the outermost electrode and the opposite electrode.

In general, a battery is composed of a positive electrode, a negative electrode and a separator positioned therebetween.

On the other hand, the laminated battery has a structure in which a positive electrode lead connecting one or more positive electrode plates and connecting them to the outside of the battery and a negative electrode lead connecting one or more negative electrode plates and connecting them to the outside of the battery are connected to a power source outside the battery packaging material. It is. In most cell designs, the opposing leads are offset from one another so that they do not touch each other.

However, when the outermost electrode of the battery having the laminated structure is the negative electrode during the manufacturing process or the product is used, a short may occur due to the physical contact between the outermost negative electrode and the positive electrode lead. Similarly, when the outermost electrode of the battery having the laminated structure is the positive electrode during the manufacturing process or during the use of the product, short may occur due to physical contact between the outermost positive electrode and the negative electrode lead. The occurrence rate of battery defects due to such a short is about 10%.

Accordingly, an object of the present invention is to prevent a short between the outermost electrode and the opposite electrode lead, which may occur during processing or during product use in a battery having a laminated structure.

In order to achieve the above object, the present invention provides at least one anode layer; At least one cathode layer laminated alternately with the anode layer; And a separator layer laminated between the anode layer and the cathode layer and on the surface of the outermost electrode layer, wherein the insulating material is applied to the bent portion of the lead of the opposite electrode that can be in physical contact with the outermost electrode. Or a stacked battery in which an insulating material is taped or an insulating material is inserted between the lead of the outermost electrode and the opposite electrode.

Hereinafter, the present invention will be described in detail.

Stacked batteries are manufactured by sequentially stacking a positive electrode and a negative electrode and inserting a separator between each electrode. At this time, the separator is placed on the outermost side, and the current collectors of the stacked electrodes are welded with ultrasonic waves to be integrated, and then different leads are connected to each electrode.

At this time, the separator 13 is present between all the electrodes to physically prevent the short by inhibiting contact between the other electrodes.

In addition, as shown in FIG. 1, the separator exists between the electrodes in a larger size than the electrodes, and when the electrode is folded in the V shape after the ultrasonic welding, the remaining separator part of the electrode is folded along the direction in which the lead is folded. All of the separators except the contacting membrane (13 of FIG. 1) are oriented and folded, and a separator exists between the electrode and the lead, thereby preventing contact between the opposite electrode and the lead to physically prevent the short.

However, two separators positioned on the upper and lower surfaces of the outermost electrode are not uniformly folded in battery manufacturing, and thus the outermost electrode may not be separated by the opposite electrode lead and the separator.

Therefore, when the welded battery is inserted into the aluminum packaging, when the welded portion is folded in the V-shape to secure space, a short may occur between the lead of the electrode located at the outermost side and the opposite electrode.

In addition, as shown in FIG. 1, when the height of the outermost electrode 11 is the same as the height of the opposite electrode lead 12, disturbances such as vibration that may occur during battery manufacturing or in a product state may occur. The outermost electrode 11 may be in physical contact with the bent portion of the lead 12 of the opposite electrode, which may cause a short between the anode and the cathode.

Therefore, as shown in FIG. 1, the present invention may apply or tape the bent portion of the lead of the opposite electrode, which may be in physical contact with the outermost electrode, with an insulating material or between the outermost electrode and the lead of the opposite electrode. It is characterized by inserting. Accordingly, the present invention may apply or tape the bent portion of the lead 12 of the opposite electrode, which may be in physical contact with the outermost electrode 11, or the insulating material 14 between the outermost electrode and the lead of the opposite electrode. By inserting N), short circuits can be prevented from occurring even when the lead of the electrode flows due to disturbance.

As the insulating material, a material such as plastic or tape can be secured and stable to the electrolyte. The material of the insulating material may be a material such as polyimide, teflon, polypropylene, polyethylene, polyvinylidene chloride, styrene butadiene rubber, bakelite, ethylene propylene terpolymers (EPDM), or a mixture or a combination of the above materials.

The bent portion of the lead of the opposite electrode, which may be in physical contact with the outermost electrode, may be coated with insulating material or wound with insulating tape. In addition, between the outermost electrode and the lead of the opposite electrode, a tape made of an insulating material and a structure having an arcuate or rectangular shape can be inserted.

Non-limiting examples of batteries in which the present invention can be used include lithium ion batteries, lithium ion polymer batteries, and lithium polymer batteries.

The present invention will be described in more detail with reference to the following examples. The present invention is not limited to the examples.

Example 1

Three positive electrodes, four negative electrodes, and five separators having a larger size than the electrodes were stacked. At this time, an insulating tape was attached to the positive electrode lead to form a battery and then packed.

Comparative Example 1

A battery was constructed in the same manner as in Example 1 except that no insulating tape was attached.

<Experiment>

After charging the batteries prepared in Example 1 and Comparative Example 1, the drop test was performed 10 times so that the lead direction collides at a height of 2 m to confirm the voltage drop degree, and the results are shown in Table 1 (Example 1) and Table. 2 (Comparative Example 1).

As shown in Tables 1 and 2, the stacked battery in which the insulating material was inserted between the outermost electrode and the lead of the opposite electrode was able to confirm the short prevention effect in the drop test. On the other hand, it was confirmed that the voltage drop phenomenon due to the short occurred in the drop test in the comparative example.

FIG. 1 is a schematic diagram illustrating a battery in which an insulating material is inserted between an outermost electrode and the lead in order to prevent a short circuit between a lead connected to the outermost electrode and the opposite electrode.

Claims (2)

At least one anode layer; At least one cathode layer laminated alternately with the anode layer; And a separator layer laminated between the anode layer and the cathode layer and on the surface of the outermost electrode layer, wherein the insulating material is applied to the bent portion of the lead of the opposite electrode that can be in physical contact with the outermost electrode. Or a stacked battery in which an insulating material is taped or inserted between a lead of the outermost electrode and the opposite electrode. The method of claim 1, wherein the insulating material is polyimide, Teflon, polypropylene, polyethylene, polyvinylidene chloride, styrene butadiene rubber, bakelite, EPDM (Ethylene Propylene Terpolymers), and a mixture or composite of each of the above 1 Laminated battery that is selected more than one species.