JPS6028106B2 - Manufacturing method for electrode plates for lead-acid batteries - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a group of electrode plates for a lead-acid battery, in which terminals are formed by melting the edges of the electrode plates.

Conventionally, the welding or integral formation of the electrode plate ears and shelf parts of lead-acid batteries, including the terminals, has been carried out by burner welding or cast-on strap methods. Burner welding is a method of melting and integrating joints using the thermal energy of a so-called gas flame, and is currently the most commonly used method. However, when welding lead alloy grid ears and shelves or terminals by gas welding, especially when the lead alloy is a Pb-Ca alloy, the Pb-Ca alloy is removed by an oxidation reaction caused by an acid-hydrogen burner flame. An oxide film was formed on the surface of the weld, making it impossible to completely fuse and integrate the weld, resulting in poor connection during the welding process. In order to achieve good welding, the combustion mixture ratio of oxygen and hydrogen in the burner flame has a subtle effect, and its adjustment requires a high degree of skill.
In addition, reducing flux has been used during welding, but even with flux, the oxide film could not be completely removed, and a good welded joint could not be obtained. In addition, as a characteristic of the thermal energy of the burner flame, the surfaces of the ears, shelves, etc. that are in contact with the burner flame melt well, but the inside of the shelves and pole-shaped terminals cannot be sufficiently heated. Therefore, the fusion zone was shallow, and sufficient mechanical strength required for the weld zone could not be obtained. In addition, in the case of the cast-on strap method, while the fusion zone is formed wide and deep, the amount of lead required to form the shelf and pole-shaped terminals increases, which increases the weight of the plate group and The fundamental drawback was that it took time for the molten lead to solidify, reducing productivity. Furthermore, in this cast-on strap method, the ears of the electrode plate are pushed into the molten lead, so the surface of the ears of the electrode plate must be kept clean and free of oxide films and deposits. However, if foreign matter adheres to the weld, it will not be possible to reliably fuse and integrate the weld, resulting in a reduction in welding strength. The present invention provides a method for manufacturing an electrode plate group that solves these various problems all at once.

The first characteristic required of the shelf portion and terminal as a current collector of a lead-acid battery is corrosion resistance.

This is because when a lead-acid battery is charged, an oxidation reaction occurs at the anode and a reduction reaction occurs at the cathode, but the anode in particular must be stable over a long period of time against corrosion due to oxidation reactions. It is. In addition, the ears of the multiple electrode plates and the shelf are integrated, and the shelf plays an important role as a current collector for each plate and extracts the electromotive force generated when the battery discharges to the outside. It is desirable that the electrical resistance of the material be as low as possible. This is to keep the so-called internal resistance of the battery low. Furthermore, the terminal and this shelf are required to have sufficient mechanical strength at the welded portion as a holder for the electrode plate group. Therefore, the properties required for the electrode plate ear, the shelf, and the weld between the shelf and the terminal are sufficient resistance to corrosion due to oxidation reactions, low conductive resistance, and high mechanical strength. Examples include. The present invention provides an effective method to satisfy these demands. Among the many types of general lead alloys, Pb-Sb
Welding of alloys is relatively free from the adverse effects of oxide films, but with Pb-Ca alloys, oxide films tend to form on the welding surfaces, making it difficult to perform good welding.

Therefore, no matter what welding method is employed, how to remove this oxide film is an important point in forming a good weld.

In the present invention, sufficient consideration is given to processing for removing the influence of this oxide film.

It is based on the fact that, in general, when metals are pretreated by pounding or heating the part to be welded, and then welded, a relatively good weld is formed.
This applies external energy to the molecules existing inside the metallographic structure of the weld zone, distorts the aligned molecular structure, and makes it easy to destroy the molecular structure within the metallographic structure, causing mixing with dissimilar metals. The purpose is to activate the so-called weld zone so that it is easier to form a structure.

External energy that activates the welded portion includes impact energy, thermal energy, and vibration energy caused by ultrasonic oscillation. In the present invention, pressurization and preheating were used as the pretreatment.

This is done by applying a smaller amount of heat than actual welding to activate the welding area, removing deposits and dirt from the welding area surface and making it clean, and instantly removing the oxide film on the lead or lead alloy surface. This enables welding on clean metal surfaces. The device is characterized in that the shelf portion for connection and the pole-shaped terminal are integrally formed at the same time by heat-welding the ear portions. In conventional general electric resistance welding, the pretreatment described above is not performed, so it is not possible to form a group of electrode plates with a good welded area.Also, with the method of pressurizing the electrode group in the stacking direction and applying current, it is difficult to stack a large number of electrode plates. Welding
The contact resistance values were unbalanced, and some parts generated heat and others did not, resulting in extremely unstable welding, but the present invention can solve these problems.

．． Hereinafter, details of the present invention will be explained with reference to embodiments shown in the drawings.

FIG. 1 is a sectional view of a lead-acid battery. In the figure, 1 is an externally protruding terminal, 2 is a lead, and 3 is a pole-shaped terminal, which are provided integrally with a shelf 4. 5 is the torpedo tank, 6 and 6' are the pole plates, 7 is the middle cut of the tank, 8 is the connector, 9 is the ear part of the pole plate, 10 is the upper lid, and 11 is the completed pole plate group. .

FIG. 2 shows the electrode plate before welding, and the tab 9 is provided with a rib-like or dowel-like projection 9a. FIG. 3 is a side view showing the positional relationship between a pair of heating and pressing jigs and a group of electrode plates. In the figure, 13 and 12 are heating and pressing jigs, and 14 is a welding power supply device. FIG. 4 is a top view of the same, and a heat generating chip 15 made of graphite is provided at the tip of each of the pair of jigs 12 and 13, and each chip has a desired shape of the electrode plate group, for example, a pole-shaped terminal. A semicircular recess 16 having a two-part cross-sectional shape is formed. In FIG. 3, the ears 9
They are brought into contact with each other and pressurized from the left and right by the shells 12 and 13.

If this pressure is 9k9/force, it will be 2000~3000
A current is applied, and due to the electric resistance value, the abutting portion of the protrusion 9a provided on the ear and the graphite electrode 15 instantaneously generate heat, thereby removing the deposits and oxide film on the surface of the welded portion as described above. Then, as this pressurization and energization continue, the portion of the ear portion 9 in contact with the graphite electrode 15 melts.
The jigs 12 and 13 gradually push forward so as to bite into the ears, and the pair of odor control tools 12 and 13 come into contact with each other as shown in FIG. 5, with the graphite electrodes holding the molten lead.

In this state, the electricity is turned off and the odor curing is maintained for a certain period of time, whereby the molten lead is cooled within the jig and a pole-shaped terminal 17 can be formed as shown in FIG. This series of pole-shaped terminal formation can be accomplished within about 3 seconds, the current value is 2000~300M, and the pressing force is 9~10k9/
The enemy was suitable.

Furthermore, since the pre-heating treatment before welding starts mainly involves heating the ears, the length of the protrusion does not really matter, and it is better to increase the amount of heat generated by reducing the abutting area.

With this method, there is no need to separately prepare the shelf part or the pole-shaped terminal as a group of electrode plates, and it is only necessary to adjust the length and thickness of the ear part and weld it, so no Zenichi parts are required. It is possible to form an electrode plate group in a state where it is not necessary, reducing weight and improving workability. In addition, although graphite was used as the heat generating chip for heating in the above example, the same effect can be obtained by forming the chip using Hastelloy, a metal with a higher electrical resistance value than the ears of the part to be externally welded. I was able to get it.

As described in detail above, the present invention facilitates welding of the electrode plate ears to each other, allows connection between the electrode plate ears without requiring any separate parts such as shelves or terminals, and makes it possible to weld the electrode plate ears to each other without requiring any separate parts such as shelves or terminals. The amount of welding can be reduced, welding can be performed in an extremely short time, and the reliability is also high.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main parts of a lead-acid battery incorporating the electrode plate group obtained in the example of the present invention, Figure 2 is a layout diagram showing the electrode plates before welding, and Figure 3 is heating at the start of welding. A diagram showing the relationship between the pressure jig and the electrode plate ears. Figure 4 is a top view before welding starts. Figure 5 is a top view when welding is completed. Figure 6 is a diagram showing the electrode plate group after welding is completed. FIG. 6, 6'... Pole plate, 9... Plate ear, 9a...
・・・Protrusion, 12, 13... Heating pressure jig, 15
... Heat generating chip, 16 ... Concavity, 17 ...
...Polar column terminal. Figure 1 Figure 2 Figure 4 Figure 5 Figure 3 Figure 6

Claims (1)

[Scope of Claims] 1. Preheat the ears of each electrode plate, and then heat the ears using a pair of heating and pressing jigs whose tips have the desired two-part cross-sectional shape of the electrode plate group terminal. A method for manufacturing a plate group for a lead-acid battery, which comprises applying pressure to melt the entire ear portion, and cooling the melted material in a pair of heating and pressing jigs that are butted together to form a plate group terminal. . 2. The method of manufacturing an electrode plate group for a lead-acid battery according to claim 1, wherein the heat generating chips at the tips of the pair of heating and pressing jigs are made of graphite or Hastelloy.