JPH07161345A - Lead-acid battery - Google Patents

Abstract

PURPOSE:To restrict the corrosion of a lug part so as to improve safety, and to minimize increase in the amount of lead by providing a protruded part wider than the lug part in the width direction of a strap part, and by containing the lug part in the protruded part. CONSTITUTION:A strap 1 is provided with a protruded part 2, and the front end of a lug part 3 of a plate is contained in the part 2, and they are wedded to each other. The width of the strap other than the part 2 is almost equal to the width of the lug. Since the part 3 is completely contained in the part 2 wider than the part 3, both ends of the part 3 are completely fixed within the strap 1 without being exposed, and the gap of the connected part between the strap 1 and the part 3 can be eliminated. Corrosion of the connected part between the strap 1 and the part 3 is restricted, and disconnection is restricted. Since the width of the strap part other than the part 2 is the same as or narrower than the width of the lug, the amount of lead necessary for the device can be reduced to a lower level compared with the case of a strap whose width is uniformly wider than the lug width.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a lead storage battery, and more particularly, in a lead storage battery having a structure in which the ears of the electrode plate are welded to form a strap portion, the strap and the ears are joined. It is intended to prevent corrosion breakage at the part.

[0002]

2. Description of the Related Art In a lead-acid battery, generally, a strap portion is formed by welding the ears of a plurality of homopolar plates. As the method of collective welding, there is a cast-on method in which the ears of the electrode plate group are inverted and inserted into the molten alloy in the mold to solidify, or the ears of the electrode plate are clamped in a comb-shaped mold and projected above it. A burning method is used in which a concave portion is formed and a lead alloy is melted and poured into the concave portion, or the lead alloy supplied in the form of additional lead is melted and flamed together with a part of the ear portion by a flame.

In recent years, efforts have been made to make calcium batteries and hybrid batteries maintenance-free, and sheet-like lead alloys such as rolled sheets of calcium alloys such as lead-calcium-tin are machined and adopted for the negative electrode grid. It started to come. However, even in these maintenance-free batteries, it is unavoidable in principle that the electrolyte solution decreases. Further, it has been pointed out that there is a problem that the liquid reduction is accelerated due to the deterioration of the use condition of the battery such as the temperature increase in the engine room in recent years.

For this reason, in the lead acid battery in which the ear portion is welded to form the strap portion, if the strap portion of the negative electrode is exposed from the electrolyte to the upper gas phase during use due to a decrease in the electrolyte, the strap and the grid are removed. It was observed that there was a phenomenon in which corrosion progressed at the joints with the ears and the wires were broken. This phenomenon is prominent when both ends of the ear are exposed without being included in the strap and a gap is seen at the joint between the strap and the ear.

Therefore, as one of the methods of eliminating the gap between the joint portion of the strap and the ear portion and including both ends of the ear portion in the strap, there is a method of making the strap width wider than the ear width.

[0006]

However, when this method is used, both ends of the ears of the electrode plate are included in the strap, and the gap between the strap and the ears can be eliminated. Since the amount of lead to be used increases as the amount of lead increases, the cost of the battery increases.

The present invention solves such a problem by suppressing the corrosion at the joint between the strap and the ear, improving the safety of the maintenance-free lead-acid battery, and minimizing the amount of lead increase accompanying it. It is intended to provide a lead storage battery that is kept to a minimum.

[0008]

In order to solve these problems, in the lead storage battery of the present invention, a strap is formed by welding the ears of a plurality of homopolar plates to form a strap portion. The protrusion has a wider width than the ear in the width direction of the portion, and the protrusion includes the ear.

[0009]

In the strap of the present invention, since the protrusion is wider than the ear and completely includes the ear, both ends of the ear are sufficiently fixed in the strap without being exposed, and the strap and the ear are joined together. The gap between the parts can be eliminated. For this reason,
Corrosion at the joint between the strap and the ear is suppressed, and disconnection is suppressed. In addition, since the strap width can be made equal to or smaller than the width of the selvages in portions other than the protrusions, the amount of lead required is smaller than that in a strap in which the width of the straps is uniformly wider than the width of the selvages.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a strap portion of the lead acid battery of the present invention. The strap 1 has a protrusion 2, and the protrusion includes the tip of the ear 3 of the electrode plate and is welded. The width of the strap other than the protrusion is almost the same as the width of the ear.

Flux treatment is applied to the ears of the electrode plate, as shown in FIG.
The lead-acid battery A of the present invention including the strap portion of the present invention shown in FIG. 4, a conventional lead-acid battery B having the same strap width as the width of the ear, and the entire strap width having the same width as the protrusion of the strap of the present invention. The conventional lead-acid battery C which is The batteries A to C are set so that the electrolyte surface is below the strap and the strap is kept exposed from the electrolyte.
A constant voltage charging test was performed at 13.8 V at 4 ° C. for 4 weeks to examine the probability of corrosion breakage of the ears. The results are shown in (Table 1).

[0013]

[Table 1]

As is apparent from (Table 1), the conventional battery B
In the case of 79.2%, most of the ears are open, whereas
Both the battery A of the present invention and the conventional battery C are 10.4.
%, Almost no disconnection was observed, and the battery A of the present invention showed corrosion resistance equivalent to that of the conventional battery C. This is because both ends of the ear portion of the battery A of the present invention are included in the protrusions and are sufficiently fixed, and corrosion breakage between the strap and the ear portion is suppressed. Needless to say, the amount of lead required for producing the battery is smaller in the A battery than in the C battery.

[0015]

As described above, in the lead acid battery of the present invention, corrosion breakage at the joint between the strap and the ear is suppressed, the safety of the maintenance-free battery is improved, and the increase amount of lead accompanying it is minimized. It can be suppressed to the limit.

[Brief description of drawings]

FIG. 1 is a diagram showing a method of configuring a strap portion according to an embodiment of the present invention.

[Explanation of symbols]

 1 strap 2 protrusion of strap 3 ear of electrode plate

Claims (2)

[Claims] 1. A lead-acid battery in which the ears of a plurality of same-polarity electrode plates are welded to form a strap portion of the electrode plate group, wherein the strap portion has a protrusion portion wider in width direction than the ears portion. ,
A lead-acid battery whose projections include the ears of the electrode plate. 2. The strap portion has a protrusion having a width wider than that of the ear, and portions other than the protrusion have a width equal to or smaller than the width of the ear. Lead acid battery.