JPH1173987A - Sealed lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the expansion of a battery jar, and uniformize a pole plate group expansion coefficient of each cell and the compression force for each cell so as to prolong the life of a battery by inserting a reinforced glass plated having hardness higher than that of a battery jar material to both the end parts of the partitioning plate and/or battery jar of a monoblock battery jar. SOLUTION: A battery jar 1 made of PP is divided into each cell chamber by a partitioning plate 3, and a pole plate group 4 consisting of a positive pole plate, a negative pole plate, and a retainer mat is inserted to each cell chamber. Reinforced glasses (SiO2 ) 10a about 1.5 mm thickness are inserted to both the end parts in the pole plate group 4 laminating direction of the battery jar 1. A reinforced glass 10b about 0.75 mm thickness is inserted to each partitioning part. The inner dimension of each cell chamber after the insertion of these reinforced glasses 10a, 10b is made equal to each other. The reinforced glasses may be interposed in the expanding direction of the battery bar 1 regardless of the partitioning part and both the end parts, depending on the structure and dimension of the battery jar. According to such a structure, noncomformities such as battery jar crack can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a contact surface between a battery case of a lead storage battery and an electrode plate group.

[0002]

2. Description of the Related Art As shown in FIG. 1, a sealed lead-acid battery generally uses a monoblock battery case in which the inside of an outer peripheral wall 2 of a battery case 1 is divided into a plurality of cell chambers by a partition plate 3. The electrode group 4 and the electrolytic solution are accommodated in the cell chamber,
The shelf 6 to which the ears 5 of the electrode group are connected is connected in series between the positive electrode and the negative electrode by the inter-cell connector 7. A lid 8 is placed on the top of the battery case 1.
The outer peripheral wall 2 of the battery case 1 and the respective partition plates 3 are brought into contact with a convex portion provided on the lid 8 so as to be opposed to the outer peripheral wall 2 and are welded to each other.

[0003] The inter-cell connector 7 in the cell chambers at both ends in the battery case 1
The positive and negative electrode poles 9 provided vertically are passed through the terminal pole insertion holes provided in the lid, and the positive and negative electrode poles 9 are disposed above the top surface of the lid 8.
It is configured by projecting the negative pole 9. As a material of the monoblock battery case, a polymer material such as ABS (acryl-butadiene-styrene), PP (polypropylene), and PE (polyethylene) is used.

[0004]

It is generally known that a lead storage battery changes the thickness of an electrode group by charging and discharging. When this change in thickness occurs in the lead storage battery having the above-described configuration, the pressure applied to the electrode group differs depending on the position in the battery case. The electrode group on the inner side in the battery case is more likely to apply pressure than the electrode groups located at both ends, and the reaction heat is more likely to be trapped inside, so the retained amount of the electrolyte (sulfuric acid component) in the retainer mat is small. State.

On the other hand, the electrode groups located at both ends of the battery case are subjected to pressure by the adjacent electrode group and the battery case.
Normally, the battery case expands toward the outside of the battery case, and the pressure is not applied much to the electrode plate group. Therefore, the compressive force applied to the electrode group located inside the battery case and the electrode group located at both ends are different. Due to this compressive force, the degree of electrode plate deterioration (active material utilization rate difference) and the amount of water evaporation (sulfuric acid utilization rate difference) differ, and the electrode group having a high compression force tends to deteriorate. Deterioration of the electrode plate (active material) places a burden on other electrode plates, and eventually all of the electrode plate group deteriorates. Therefore, the electrode groups located at both ends of the battery case tend to have a longer life than the electrode groups located inside.

Further, when the electrode case expands or the pressure inside the battery increases, the battery case expands in the direction of the outside of the battery case (lamination), so that the appearance is very poor and the expansion is extremely severe. , Cracks occur in the battery case, sulfuric acid inside the battery leaks,
There was also a possibility of sulfuric acid corrosion and sulfuric acid short circuit of the battery peripheral equipment.

An object of the present invention is to solve such a problem, and it is an object of the present invention to suppress expansion of a battery case and extend the life of a sealed lead-acid battery.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a structure in which a partition plate of a monoblock battery case and / or a plate having hardness higher than the material of the battery case are provided at both ends of the battery case. It is assumed that.

With this configuration, even if expansion due to a change in the thickness of the electrode group due to charge and discharge occurs, the partition of the battery case and / or
Alternatively, by interposing plate-like materials having higher hardness than the material of the battery container at both ends of the battery container, the electrode plate group expansion coefficient of each cell and the compressive force of each cell can be made uniform, and the positive electrode plate and the negative electrode The distance between the electrode and the plate and the degree of compression of the retainer mat interposed therebetween are made uniform, and the utilization rates of the active material and sulfuric acid can be made substantially uniform. This equalizes the degree of electrode plate deterioration,
Since the capacity and the life of each cell can be made equal, the life of the unit cell can be extended.

In addition, it is possible to prevent expansion of the battery case in the direction of the outside (lamination), without causing deterioration in appearance, cracking of the battery case, and leakage of sulfuric acid inside the battery. Can be prevented beforehand.

[0011]

FIG. 1 is a partially cutaway perspective view of a lead-acid battery according to the present invention. The battery case 1 made of PP is divided into each cell chamber by a partition plate 3, and an electrode group 4 made up of a positive electrode plate, a negative electrode plate, and a retainer mat is inserted into each cell room. Both ends of the battery case 1 in the electrode plate stacking direction have a thickness of 1.
A 5 mm tempered glass (SiO ₂ ) 10a is inserted. Further, a tempered glass 10b having a thickness of 0.75 mm is inserted into each partition. After inserting the tempered glass, the inner dimensions of each cell chamber are the same.

[0012]

FIG. 2 is a graph showing cycle life test characteristics in an embodiment of the present invention and a conventional example. Tables 1 and 2 show the capacity of each cell calculated from the cell voltage-discharge time characteristics at 100 cycles in the example of the present invention and the conventional example. The battery used was 12V 60Ah, the ambient temperature was 25 ° C, the discharge was 1 / 3C (9.9V cut), and the charge was 0.25C until the voltage reached 14.5V so that it reached 115% of the discharge amount at a two-stage constant current. , 0.05C and the remaining time (about 4 hours). The pause between discharge and charge is one hour, and 0.5 hour between charge and discharge.

[0013]

[Table 1]

[0014]

[Table 2]

From these comparative experiments, it can be said that in the embodiment of the present invention, the variation in capacitance between cells is small and the life is extended. In the conventional example, it can be considered that the cell expands in the outer direction of the battery container in the both-end cells, and the compressive force is reduced. On the other hand, in the internal cell, the compression state increases, the distance between the electrodes is not uniform, the life of the electrode plate is short, and it can be considered that this is a factor that promotes the deterioration of the cell. Therefore, the embodiment of the present invention has a longer life than the conventional embodiment.

[0016]

[Table 3]

FIG. 3 shows the expansion degree of the battery case in the embodiment of the present invention and the conventional example. The used batteries and conditions were the same as those in the above-described embodiment. The measurement part in the battery case is a surface portion of the outer wall of the battery case corresponding to the center part (the maximum expansion point) of the electrode plate. Compared with the conventional example, the battery case expansion was 1/3 or less at the time of 500 cycles, and it can be seen that the battery case hardly expanded in this embodiment.

In the structure of this embodiment, tempered glass is interposed at both the partition and both ends from the battery case.
Depending on the battery case structure (shape) and dimensions, it may be interposed in the direction in which the battery case expands, regardless of the partitions and both ends.

In addition, if the material used is an oxide such as glass, etc., it has high hardness and is resistant to an electrolytic solution.
The effects of the present invention can be achieved.

[0020]

As is apparent from the above description, even if expansion due to a change in the thickness of the electrode group due to charging and discharging occurs, the partition and / or both ends of the battery case have higher hardness than the battery case material. By interposing a plate such as an oxide material, the plate group expansion coefficient of each cell and the compressive force of each cell are made uniform, and the distance between the positive electrode plate and the negative electrode plate and the retainer mat interposed between them The degree of compression can be made uniform, and the utilization rates of the active material and sulfuric acid can be made substantially uniform. As a result, the degree of electrode plate deterioration can be made uniform, and the capacity and life of each cell can be made uniform, thereby extending the life of the unit cell.

Further, by arranging an oxide material having a higher hardness than the material of the battery case at both ends of the battery case, it is possible to prevent the battery case from expanding, and it is possible to prevent problems such as cracking of the battery case.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a storage battery of the present invention.

FIG. 2 is a diagram showing cycle life test characteristics in an example of the present invention and a conventional example.

FIG. 3 is a diagram showing expansion of a battery case in an embodiment of the present invention and a conventional example.

[Explanation of symbols]

 Reference Signs List 1 battery case 2 outer peripheral wall 3 partition plate 4 electrode plate group 10 tempered glass

Claims (2)

[Claims] An interior of a battery case is divided into a plurality of cell chambers by a partition plate, and an electrode plate group is inserted in the cell chamber in the stacking direction. A sealed lead-acid battery characterized by being provided with a plate having a higher hardness. 2. The inside of a battery case is divided into a plurality of cell chambers by a partition plate, and an electrode plate group is inserted into the cell room in the stacking direction. A sealed lead-acid battery characterized by having a plate with a high height.