JP2518093B2 - Battery manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICABILITY The present description is a method of manufacturing a battery for improving the current collecting property between the positive electrode and the positive electrode output terminal of the battery.

2. Description of the Related Art In a flat battery with a hermetic seal, a pin-shaped positive electrode output terminal 1 is inserted into the positive electrode as shown in FIG. 4 and a positive electrode current collector 2 made of stainless steel mesh is embedded in the positive electrode. As shown in FIG. 5, the bent contact portion 3 of the positive electrode output terminal 1 is brought into contact with the positive electrode current collector 2 to collect current, or the positive electrode output terminal 1 is dish-shaped as shown in FIG. A method is employed in which a contact portion 3 is provided and the positive electrode current collector 2 is brought into contact with the contact portion 3 to collect current.

 Reference numeral 4 is a hermetic seal part.

However, basically, in the contact current collection, contact failure occurs due to external vibration, expansion and contraction due to heat, and the like.
In a normal cylindrical battery, a part of the positive electrode current collector is welded to the positive electrode output terminal, but a small battery has a problem that a space required for welding cannot be provided inside the battery.

In the case of the conventional flat type battery, in the method of inserting the pin-shaped positive electrode output terminal 1 into the positive electrode as shown in FIG. 4, the positive electrode may collapse after the insertion, resulting in poor contact. When the positive electrode output terminal 1 does not contact the positive electrode current collector 2 embedded in the positive electrode, the active material and the positive electrode output terminal 1
Since the contact with the product was defective, poor current collection still occurred.

As shown in FIG. 5, the positive electrode output terminal 1 is bent and brought into contact with the positive electrode current collector 2 on the surface of the electrode, or as shown in FIG. 6, the dish-shaped contact portion 3 and the positive electrode current collector 2 are brought into contact with each other. When the current is collected by making the positive electrode and the positive electrode current collector 2 contact each other favorably, and the positive electrode current collector 2 and the positive electrode output terminal 1 favorably contact each other, poor contact is unlikely to occur. However, since the positive electrode output terminal 1 is arranged so as to be pressed against a part of the positive electrode current collector 2, the positive electrode current collector 2 is deformed by the pressure when the positive electrode is pushed, and the positive electrode current collector 2 is deformed. This may cause peeling between the body 2 and the positive electrode or a short circuit between the positive electrode current collector 2 and the battery lid.

Further, as the thickness of the electrode increases or decreases, contact failure occurs when the electrode is thin, and hermetic seal portion 4 when the electrode is thick.
A defect that damages the glass of occurs.

Means for Solving the Problem The present invention is directed to a completely sealed battery having a plurality of hermetically sealed positive electrode output terminals 1. The positive electrode current collector and the positive electrode output terminal are in complete contact with each other without breaking the positive electrode. Therefore, a positive electrode current collector having a fitting portion for the positive electrode output terminal is provided on the electrode so that the positive electrode output terminal can pierce the fitting portion even if there is an error in the electrode size, and the hermetically sealed battery lid is used. Make sure that no extra force is applied to the seal. Then, a large current is instantaneously passed between the two positive electrode output terminals to weld the positive electrode current collector and the positive electrode output terminal.

The electrical contact between the positive electrode current collector and the positive electrode output terminal is kept good, and stress is not applied to the positive electrode current collector and the hermetic seal, so that contact failure or damage to the hermetic seal portion does not occur.

Example An example of the present invention will be described.

As shown in FIG. 1, the battery has a structure in which the positive electrode active material 5 and the negative electrode active material 6 are arranged to face each other with the separator 7 interposed therebetween,
The negative electrode active material 6 is pressure-bonded to the negative electrode current collector 9 made of a metal mesh spot-welded to the battery container 8. The positive electrode active material 5 is closely attached to the positive electrode current collector 2, and the positive electrode current collector 2 is
A battery lid 10 is connected to a plurality of positive electrode output terminals 1 hermetically sealed by an electrically insulating material such as glass or ceramic.

In order to satisfactorily connect the positive electrode active material 5 and the positive electrode output terminal 1, the positive electrode current collector 2 having the fitting portion 11 as shown in FIG. 1 is arranged on the surface of the positive electrode output terminal side. Further, as shown in FIG. 2, the positive electrode current collector 2 can be embedded in the positive electrode active material 5. The positive electrode active material 5 on the embedded positive electrode current collector 2 is scraped off only at the positive electrode output terminal 1.

As the positive electrode current collector 2, a conductive material such as a metal mesh other than a metal plate can be used, but stainless steel is most suitable as a material that is resistant to corrosion by the battery contents and can be resistance-welded.

An example of the positive electrode current collector 2 is shown in A of FIG. A notch 12 is provided around the fitting portion 11 so that the circumference of the fitting portion 11 can be opened when the positive electrode output terminal is inserted.

Next, the positive electrode of the battery and the method of manufacturing the battery will be described. A gum-like positive electrode active material containing a Teflon binder is prepared in advance, and an amount of the positive electrode active material 5 corresponding to a desired thickness is prepared.
Is placed in a mold, the positive electrode current collector 2 is placed thereon, and then pressed while removing water at a predetermined pressure to form a resilient plate-shaped positive electrode. The positive electrode insulating frame 13 was housed, and the negative electrode active material 6 was pressure-bonded to the separator 7
It is placed in a battery container 8 in which the electrolyte is injected. After that, the battery container 10 is covered with the battery lid 10, and the welding portion 14 between the battery lid 10 and the battery container 8 is projection-welded while being pressurized by the resistance welding machine. In this work, the positive output terminal 1
Since there is a possibility that a positional deviation occurs between the fitting portion 11 and the fitting portion 11, the insertion guide 15 as shown in FIG. 3B is required.

Further, in the embodiment of the present invention, the diameter of the fitting portion 11 and the positive electrode current collector 2 are
It is impossible to make the diameters of the same exactly the same because there is a dimensional error due to manufacturing, and therefore, the fitting portion 11 having the same diameter as the positive electrode output terminal 1 cannot be provided. Even if the fitting portion 11 having the same diameter as the positive electrode output terminal 1 can be provided, a good fitting state cannot be expected and is not practical. Therefore, as shown in FIG. 3A, a radial notch 12 is formed in a fitting portion 11 that is smaller than 1/100 to 5/100 mm so that the positive output terminal 1 can be bent back when inserted. The positive output terminal 1
So that it is firmly fixed.

Further, in order to prevent the fitting portion 11 of the positive electrode current collector 2 and the positive electrode output terminal 1 from being unable to be fitted when they are misaligned, a guide formed with a taper as shown by B in FIG. By providing 15, the positive electrode output terminal 1 is arranged at a normal position along the guide 15 even when there is a positional deviation of about 0.5 mm.

Furthermore, in order to improve the reliability of the contact current collection, the one in which the existing socket 16 is provided in the positive electrode current collector 2 is shown in C in FIG. The original purpose of the ordinary socket is to insert the lead wire of the electronic component, and the function thereof is the same as intended by the present invention. However, the material used is stainless steel in order to stabilize the metal material in the electrolytic solution. When such a socket 16 is used, the stress applied to the hermetic seal portion 4 is almost eliminated, and the defects resulting from it are eliminated.

Further, as shown by D in FIG. 3, the positive electrode output terminal 1
For the purpose of instructing that, a material 17 having high electrolytic solution resistance and high elasticity, such as polypropylene, is provided in a part of the fitting portion 11,
When the positive electrode output terminal 1 is inserted into the fitting portion 11, the fitting portion 11
It is also possible to make contact on one side.

After the positive electrode current collector 2 and the positive electrode output terminal 1 are fitted as described above, a large current is instantaneously passed between the positive electrode output terminals so that the contact portion between the positive electrode current collector 2 and the positive electrode output terminal 1 is resistive. Weld.

After the positive electrode current collector 2 and the positive electrode output terminal 1 are fitted as described above, a large current is instantaneously passed between the positive electrode output terminals so that the contact portion between the positive electrode current collector 2 and the positive electrode output terminal 1 is resistive. Weld.

In addition, 18 and 18a are insulating plates and insulators that insulate the battery lid 10 from the positive electrode current collector 2 or the positive electrode active material 5, and 19 is a negative electrode output terminal, which is a negative electrode active material via the battery lid 10 and the battery container 8. Conducted to 6.

Battery defect rate before and after implementation of the present invention (n = 20)
Table 1 shows the transition of.

EFFECTS OF THE INVENTION As described above, according to the present invention, there is no contact failure between the positive electrode current collector and the positive electrode output terminal, and no failure due to damage to the electrically insulating material of the hermetically sealed portion. It is of great industrial value, such that there is no variation and stable battery charge / discharge performance is obtained.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the battery of the present invention, FIG.
FIG. 3 is a schematic sectional view showing another embodiment of the present invention, and FIG. 3 is a sectional view showing an embodiment of the positive electrode current collector used in the battery of the present invention.
A is a structure in which a notch is provided around the fitting portion, B is a structure in which a tapered guide is provided, C is a structure in which an existing socket is provided, and D is electrolytic solution resistant in a part of the fitting portion. The structures provided with a highly elastic material are shown respectively. FIG. 4 is a sectional view of a conventional flat type battery, FIG. 5 is a sectional view of another conventional flat type battery, and FIG. 6 is a sectional view of yet another conventional flat type battery. 1 is a positive electrode output terminal, 2 is a positive electrode current collector, 5 is a positive electrode active material,
8 is a battery container, 10 is a battery lid, 11 is a fitting part, 12 is a notch, 15 is a guide, 16 is a socket, 17 is a material

Claims (1)

(57) [Claims] 1. In a battery in which a plurality of positive electrode output terminals are sealed in a battery container via an electrically insulating material and the battery lid and the battery container are sealed by welding, the positive electrode output terminal is inserted in the positive electrode of the battery. After disposing the positive electrode current collector having a fitting portion for inserting the positive electrode output terminal in the fitting portion, a current is passed between the output terminals of the positive electrode to weld the positive electrode current collector and the positive electrode output terminal. A method of manufacturing a battery, comprising: