JPH09190835A - Lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead-acid battery equipped with a connection part, embodied in a small size, and assuring easiness in executing works, with which it is possible to perform connections certainly while the structure remains simple. SOLUTION: Electrode plate tabs 1, 2 are protruded at the top of a bulkhead 3, and an inter-cell connecting piece 4 made of a metal having a melting point higher than the electrode plate tabs 1, 2 is covered with a lead alloy. The tops of all negative electrode tabs 2 of one of two adjoining cells are joined with the tops of all positive electrode tabs 1 of the other cell, wherein the upper part of the electrode tabs 1, 2, the upper part of bulkhead 3, and connective conductor 4 are embedded in filler adhesives 10, 11, and the lid rear cavity bounded by a weir 7 dangling from a lid is filled with the adhesives 10, 11. That is, the connective conductor 4 also has a function of a strap.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a negative electrode absorption type sealed lead acid battery, and more particularly to a strap and a cell connecting portion thereof.

[0002]

2. Description of the Related Art In a negative electrode absorption type sealed lead-acid battery, a strap for connecting and joining the ears of a plurality of electrode plates and an inter-cell connection for connecting different polarity electrode plate groups of adjacent cells. Regarding connection conductors, many structures and manufacturing methods have been proposed and implemented for batteries of various sizes and applications.

In a lead-acid battery for an automobile using a polyolefin-based polypropylene-polyethylene copolymer (EPP) for a battery case or a lid, a molten lead alloy is poured into a mold, and the electrode ears of an inverted electrode plate group are immersed therein. The most common is the strap forming method (COS welding) for solidifying by means of the above. With this method, it is not possible to use an adhesive to maintain the air-tightness of the connection between cells, so the protrusions of the lead alloy band integrated with the strap are inserted into the perforations of the partition wall from the left and right, and mechanically applied from the outside. In many cases, the protrusions that come into contact with each other in the perforated portion of the partition wall are resistance-welded to form electricity while pushing the metal strip. In this case, the inter-cell connecting conductor is placed above the electrode ears.

In a small battery using a copolymer of acrylonitrile, styrene and butadiene (ABS) for the battery case and lid, the electrode ears are projected onto the inner lid and the molten lead alloy is added on the inner lid to weld the ears. , There is also one in which the electrode plate group is inverted to perform C0S welding, and one in which COS welding is improved and a thin plate container of copper or aluminum is used instead of the mold, and the container is used as a strap or an inter-cell connecting conductor. . In these small batteries, the straps and cell-to-cell connections are filled with acid-resistant thermosetting resin such as epoxy resin.

Further, the electrode ears are inserted into and projected from the inner lid, and the lead alloy is impregnated into a base material made of a porous body or a linear bundle using a conductive material having a higher melting point than the lead alloy. There is also a proposal to connect the strap and the cell with a conductor.

The structure or manufacturing method of the strap or the inter-cell connecting conductor as described above has the following drawbacks.

That is, in COS welding or a similar method, it is necessary to invert the electrode plate group placed in the battery case. At this time, the electrode plate may drop due to gravity, and the vertical position of each electrode plate may shift. That the volume of the strap is large in order to satisfactorily bond the electrode plate ear and the strap, and
When connecting the cells with the perforated part of the partition wall, a large amount of lead alloy and a large upper space are required to maintain the airtightness of the part, and when the connection part between the cells is embedded in epoxy resin, etc., it is sealed. This is because the EPP resin which is preferable for the shaped battery cannot be used because of poor adhesion.

Further, in the method of projecting the electrode plate ears on the inner lid and welding on the inner lid, the size and position of the holes provided in the inner lid,
It is difficult to match the size and position of the electrode plate ears, and workability is poor.

[0009]

According to the present invention, the ears of the positive and negative electrode plates are projected above the upper end of the partition wall, and the connecting conductor between the cells is made of a metal having a melting point higher than that of the electrode ears, and the surface thereof. Is coated with a lead alloy, and the lead alloy coating both end portions of the connection conductor is respectively joined to all the top edges of the negative electrode plate of one cell and all the top edges of the positive electrode plate of an adjacent cell. The upper part of the ear, the upper part of the partition wall, and the connecting conductor are all buried in the inside of the filling adhesive, and the filling adhesive is filled in the space behind the lid separated by the weir hanging from the lid, It also has the function of a strap, and the container and lid are made of polyolefin resin and the filling adhesive is made of a thermoplastic resin having a lower softening point than the container and lid, or at least the partition wall. On the upper end of A surface treatment that imparts a functional group is applied to make it adhesive, and the filling adhesive is a thermosetting resin. Furthermore, the filling adhesive has two layers, and the temperature is higher than the melting temperature of the electrode ears. By mounting the connection conductor on the electrode plate ears, and by fusion bonding the lead alloy covering the connection conductor and the electrode plate ears, the drawback of the negative electrode absorption type lead-acid battery is solved. is there.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The lead-acid battery according to the present invention uses an inter-cell connection conductor in which the electrode plate ears protrude beyond the upper end of the partition wall and which is made of a metal having a melting point higher than that of the electrode plate ears and whose surface is coated with a lead alloy. Then, all of the negative electrode plate top edges of one of the two adjacent cells and all the positive electrode plate top edges of the other cell are joined together, and the upper part of the plate plate ear, the upper part of the partition wall, and the connecting conductor are all filled. The filling adhesive is filled in the inside of the adhesive, and the filling adhesive is filled in the space behind the lid separated by the weir hanging from the lid, that is, the connecting conductor also has the function of the strap. By doing so, the conventional problems can be solved, the structure is simple, the workability is good, and reliable connection is made, and the battery can be made compact and without weight.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment.

FIG. 1 is a longitudinal sectional view of an essential part showing an inter-cell connecting portion of the lead storage battery of the present invention, and FIG. 2 is a top view showing an example of the arrangement of electrode plates of the lead storage battery of the present invention and the shape of the inter-cell connecting conductor. 3 is a top view showing another example of the arrangement of the electrode plates and the shape of the inter-cell connection conductor of the lead acid battery of the present invention. In the figure, 1 is a positive electrode plate ear,
Reference numeral 2 is a negative electrode plate ear, 3 is a partition wall between cells, and the positive and negative electrode plate ears 1 and 2 project above the upper end of the partition wall 3. Four
Is a connecting conductor between cells, which is a molded product of metal such as iron, copper, nickel, and aluminum, and its melting point is higher than the melting point of the electrode plate ear. The surface is covered with a lead alloy 5 such as a lead-tin alloy or a lead-antimony alloy.

The lead alloy coating one end of this connecting conductor is
All the positive electrode tabs of one cell of two adjacent cells are joined, and the lead alloy coating the other end is joined to all the negative electrode tabs of the other cell. The typical joining method is to heat the connection conductor and form a lead alloy molten metal coating on the surface thereof, and then place the coating on the positive electrode plate ear 1 and the negative electrode plate ear 2 to form the electrode plate ears 1 and 2 Is melted at the upper end, and the lead alloy covering the connection conductor and the electrode plate ear are welded and solidified. At this time, the lead alloy coating the surface of the connection conductor may move to the low temperature portion, and a part of the connection conductor may be exposed. It should be noted that it is preferable to apply a flux in advance to the upper end of the electrode plate to improve the bonding. Further, when the metal used as the connection conductor is dissolved and saturated in the lead alloy molten metal in which the connection conductor is dipped, it is possible to prevent the connection conductor itself from being dissolved in the lead alloy molten metal.

Reference numeral 6 denotes a lid, 7 and 7'denotes coughs hanging from the lid, 8 denotes a cylindrical valve seat projecting from the lid 6'outside the weir 7 ', and 9 is made of an elastic material such as rubber. It is a valve.
The material of the battery case having the partition wall 3 as its part and the lids 6, 6'having the weirs 7, 7'as part thereof is preferably a polyolefin resin such as a copolymer of polyethylene and polypropylene (EPP), but acrylonitrile. ·styrene·
It may be a butadiene copolymer (ABS) resin. 10 and 11 are filling adhesives, which are filled in a space which is divided into at least two sides by a weir 7, 7 '. The upper part of the plate ears 1 and 2, the upper part of the partition wall 3, the connecting conductor 4 and All of the lead alloy 5 to be coated is buried inside the upper layer 10, but the upper portion of the partition wall 3 is buried inside the lower layer 11.

Filling adhesives 10 and 11 are epoxy-based,
It is a hot-melt resin mainly composed of a thermosetting resin such as polyester or phenol, or a thermoplastic resin such as polyolefin, vinyl acetate or polyester, which must have excellent acid resistance.

When the material of the battery case and the lid is a resin having poor adhesiveness such as a polyolefin-based material, at least the upper end of the partition wall is subjected to plasma treatment, chlorinated polyolefin coating, or flame treatment. By
When a functional group is provided on the surface of the resin, a filling adhesive made of a general thermoplastic resin can be used. In addition, when a hot-melt resin having a low molecular weight and a softening point lower than those of the battery case and the lid is heated to have a low viscosity, and when the resin is filled, curing is quick and workability becomes excellent.

In particular, the olefin-based hot-melt resin mainly composed of low-molecular-weight atactic polypropylene has similar physical properties to the battery case and lid made of the polyolefin-based resin, and therefore has good adhesiveness. In FIG. 1, the filling adhesive is divided into two layers, 10 and 11, but in this case, the upper layer 10 is a thermosetting resin having good adhesion to a lead alloy or a metal, and the lower layer 11 is a battery case. Further, it is desirable to use a thermoplastic resin having good adhesion to the lid. However, the filling adhesive layer may be a single layer.

For filling the filling adhesive layer, the lid is inverted and a predetermined amount is poured into the weirs 7, 7'which hang down from the lid, while the electrode ears 1, 2 are connected to the connecting conductor 4 in the battery case. This is performed by welding, fixing and holding the electrode plate group upside down, and burying the upper part of the electrode plate ear, the upper part of the partition wall, and the connection conductor in the uncured filling adhesive 10. When the filling adhesive layer has two layers, it is injected from the opening of the valve seat 8 after the above.

Unlike the normal liquid type battery, the negative electrode absorption type sealed lead acid battery has a limited electrolyte so that there is almost no flowing electrolytic solution, so that the airtightness of the partition wall and the back of the lid is slightly increased. Then, even if it is bad, the leak between cells can be ignored. However, since the high melting point metal used as the connecting conductor has poor acid resistance, it may be cut even if it comes into contact with a small amount of electrolytic solution. Thus with positive and negative plate ears,
It must be airtightly bonded to the filling adhesive. 12 is an upper lid.

The shape of the connecting conductor 4 differs depending on the arrangement of the electrode plates in the cell. When a plurality of electrode plates are arranged in the cell so that they are perpendicular to the partition wall 3 as shown in FIG. 2, the shape of the connecting conductor is H-shaped, but as shown in FIG. On the other hand, when the electrode plates are arranged in parallel, the shape becomes a single letter. In addition, the width and thickness of the connecting conductor are selected in consideration of the dimensions of the electrode plate ears and the electric resistance. Furthermore, it may be a porous body or a stranded wire. 13 is a battery case.

[0021]

Since the lead acid battery of the present invention has the above structure, it has the following advantages. (1) Since the electrode plate group in which the electrode plate ears are fixed by connecting conductors is inverted, the electrode plates do not fall and move due to the gravity of the electrode plates, and thus the electrode plates do not become irregular. (2) Since a metal having good conductivity such as copper or aluminum can be used as the connecting conductor, the size and weight can be reduced. (3) The connection between cells can be structurally downsized. (4) Since a polyolefin-based resin can be used, it is possible to reduce the amount of water that is lost by permeating the wall surface of the battery case as compared with a battery using a conventional ABS resin battery case. (5) Since the filling adhesive can be a hot melt resin, curing can be performed in a short time. (6) The strap and the cell-to-cell connecting portion can be formed by a simple process of placing a high-temperature connecting conductor on the ear.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an essential part showing an inter-cell connecting portion of a lead storage battery of the present invention.

FIG. 2 is a top view showing an example of the arrangement of electrode plates and the shapes of inter-cell connection conductors.

FIG. 3 is a top view showing another example of the arrangement of electrode plates and the shapes of inter-cell connection conductors.

[Explanation of symbols]

 1 Positive Plate Ear 2 Negative Plate Ear 3 Partition 4 Inter-Cell Connecting Conductor 5 Lead Alloy 6,6 'Lid 7,7' Cough Hanging from Lid 10 Filling Adhesive 11 Filling Adhesive 12 Upper Lid 13 Battery Case

Claims (4)

[Claims] 1. The ears of the positive and negative electrode plates project above the upper ends of the partition walls, the connecting conductors between cells are made of a metal having a melting point higher than that of the ears of the plate, and the surfaces thereof are coated with a lead alloy. , A lead alloy covering both ends of the connection conductor is respectively joined to all the negative electrode plate ear tops of a certain cell and all the positive electrode plate ear tops of adjacent cells, and the upper part of the electrode plate ear and the upper part of the partition wall. The connecting conductor is embedded in the filling adhesive, and the filling adhesive is filled in the space behind the lid separated by the weir hanging from the lid. Negative electrode absorption type sealed lead-acid battery that also has the function of. 2. The negative electrode absorption type seal according to claim 1, wherein the battery case and the lid are made of polyolefin resin, and the filling adhesive is made of a thermoplastic resin having a softening point lower than that of the battery case and the lid. Type lead acid battery. 3. The surface treatment for imparting a functional group to at least the upper end portion of the partition wall so as to have adhesiveness, and the filling adhesive is a thermosetting resin.
Negative electrode absorption-type sealed lead-acid battery according to. 4. The negative electrode absorption type seal lead acid battery according to claim 1, 2 or 3, wherein the filling adhesive has two layers.