JPH0869788A - Lead-acid battery - Google Patents

Abstract

PURPOSE: To prevent the break through by the corrosive elongation of a lattice body by shaping a bag-shaped separator such that it forms a curved arc, with its starting point as the rear of the rib part of a base contacting with a negative electrode, wrapping the negative electrode. CONSTITUTION: For this lead-acid battery, lead-calcium-tin alloy is used for both lattices of a positive electrode 1 and a negative electrode 2, and a bag- shaped separator 3 wraps the negative electrode 2. The base part 5 of the separator 3 in contact with the negative electrode 2 draws an arc in the shape of a curve, with its starting point as the rear of the rib part 4 projecting on the side of the positive electrode 1. This prevents the break through of the separator 3 by the use at high temperature, and also improves the charge acceptability by the use with high load. Moreover, shaping it in the said curve will produce a gap between the separate 3 and the negative electrode 2, and improve the diffusion property in the vicinity of the negative electrode 2, and suppress the sharp rise of the concentration of electrolyte. So, the potential of the negative electrode during charge is optimized, and charge shortage ceases to occur.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead storage battery, particularly a lead storage battery for automobiles, in which a lead-calcium-tin alloy is used for both the anode and cathode grids, and a cathode plate is wrapped in a bag separator. Related to the improvement of.

[0002]

2. Description of the Related Art In a lead-acid battery for an automobile, an electrode plate in which a grid is filled with a predetermined active material paste, particularly an anode plate, is generally used by being housed in a bag-shaped separator made of microporous polyethylene. It is becoming a reality.

With this structure, the positive and negative plates are separated from each other, and the active material dropped from the grid when the battery is used is stored in a bag to prevent an electrical short circuit between the positive and negative plates due to the dropped active material. .

In addition, as the performance of automobile engines has increased in recent years, the ambient temperature of the batteries installed in the engine room has become extremely high. If the batteries are used at such high temperatures, the anode plate will be corroded. There is a case in which the lattice body is accelerated and deformed due to a large extension, and it breaks through the bag-shaped separator and comes into contact with the cathode plate to cause an internal short circuit.

In order to prevent this phenomenon, there is also a battery having a structure in which instead of the anode plate, a cathode plate having a small elongation is wrapped in a bag-shaped separator to prevent the separator from breaking through.

[0006]

However, in recent automobiles, the number of electric components inside the automobile has increased remarkably as the engine performance has increased, and the battery for automobiles has a high ambient temperature and a very deep load, resulting in a very deep discharge depth. It is getting deeper.

When the battery is used under such a high temperature and high load condition, a battery having a structure in which a cathode plate is wrapped with a bag-like separator in place of the conventional anode plate, particularly a positive battery,
In a battery that uses a lead-calcium-tin alloy for the cathode grid, it is effective in suppressing the cracking of the separator, but the charge receptivity is low due to deterioration of the diffusion of the electrolyte near the cathode plate. Therefore, there is a problem in that the anode plate is not sufficiently charged, and the battery as a whole has a short life due to insufficient charging at an early stage.

In order to solve the above problem, there is a separator in which a small rib having a height of about 0.1 mm is provided on the entire surface of the separator in contact with the cathode plate, but the sufficient effect has not been obtained.

The present invention solves these problems, and prevents the separator from breaking through due to the corrosion extension of the grid of the anode plate, and improves the short life due to insufficient charging due to a decrease in charge acceptability. It provides a lead storage battery.

[0010]

In order to solve the above-mentioned problems, the lead-acid battery of the present invention has a bag-shaped separator that encloses a cathode plate, and a base portion of the separator that is in contact with the cathode plate is a rib portion protruding toward the anode plate side. It is characterized in that it has a curved arcuate shape with the back side as the starting point.

[0011]

The lead-acid battery of the present invention has a structure in which a lead-calcium-tin alloy is used for both grids of the anode and the cathode, and the cathode plate is wrapped with a bag-shaped separator, and the base portion of the separator in contact with the cathode plate is the anode. Since it has a curved arc shape starting from the back side of the rib protruding to the plate side, it prevents the separator from breaking through due to use at high temperatures, and improves charge acceptance by use under high load, It is intended to improve the life.

That is, in the conventional configuration, the concentration of the electrolyte solution near the cathode plate rises early during charging due to the deterioration of the diffusion of the electrolyte solution near the cathode plate, and the appearance of charging progresses and the cathode potential changes. The polarity was swiftly changed, and the charging current decreased before the anode plate was sufficiently charged, resulting in insufficient charging.

On the other hand, according to the present invention, the base portion of the separator which is in contact with the cathode plate is formed into a curved arc shape, thereby creating a space between the separator and the cathode plate, and thereby the vicinity of the cathode plate. The diffusivity of the electrolytic solution is improved, and a sharp increase in the electrolytic solution concentration near the cathode plate can be suppressed.

With the above operation, the reversal speed of the cathode potential during charging is optimized, and the decrease in charging current is suppressed until the anode is sufficiently charged, thereby improving insufficient charging.

[0015]

Embodiments of the present invention will be described below.

FIG. 1 shows an outline of a state in which a cathode plate is housed in the separator of the present invention and superposed on the anode plate.

In the drawing, 1 is an anode plate, 2 is a cathode plate, 3 is a separator made of microporous polyethylene resin, 4 is a rib protruding toward the anode plate side of the separator, and 5 is a separator base portion which is an arc. Shows the shape.

Next, using this bag-shaped separator, a battery having a nominal specification of 12V55Ah was prepared, which was designated as Battery A of the present invention.

For comparison, a battery using a separator having a small rib formed on the entire surface of the separator in contact with the cathode plate was prepared as a conventional battery B.

Then, these batteries were discharged in a 75 ° C. atmosphere at 14.0 V (maximum charging current 25 A) for 10 minutes and discharged at 25 A for 4 minutes as one cycle, and discharged at 582 A for 30 seconds every 480 cycles. Then, a test was conducted to determine the end of life at the time when the terminal voltage at 30 seconds became 7.2 V or less.

The results are shown in FIG. As shown in FIG. 2, in the conventional battery B, the terminal voltage drastically dropped and the life was early, whereas in the battery A of the present invention, the terminal voltage drop was gentle and the life was long and good results were obtained. there were.

When the batteries after these tests were disassembled and the electrode plate group was observed, almost no deterioration was observed in both the anode plate and the cathode plate of battery B, but the state of the active material of the anode plate showed a discharge tendency. It is considered that there was insufficient charge during the cycle.

On the other hand, in the battery A, both the anode plate and the cathode plate were in a deteriorated state corresponding to the number of cycles, showing that the charge / discharge balance during the cycle was favorable.

[0024]

As described above, the lead-acid battery of the present invention uses the lead-calcium-tin alloy in both the anode and cathode grids, and the cathode plate is wrapped with the bag-shaped separator. The base part has a curved arc shape starting from the back side of the rib part protruding toward the anode plate side, and prevents the separator from breaking through due to the expansion of the anode plate due to corrosion when using the battery. The short life due to insufficient charging due to deterioration of charge acceptability in the conventional structure in which the cathode plate is wrapped in the bag-shaped separator is improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing a state where a cathode plate is housed in a separator of the present invention and is superposed on an anode plate.

FIG. 2 is a diagram showing the results of a life test of the present invention and a conventional battery.

[Explanation of symbols]

 1 Anode plate 2 Cathode plate 3 Bag-shaped polyethylene separator 4 Separator rib part 5 Separator base part

Claims (1)

[Claims] 1. A lead-calcium-containing material for both the anode and cathode grids.
Using a tin-based alloy, a bag-shaped microporous resin separator is wrapped around the cathode plate, and the bag-shaped separator has its base portion in contact with the cathode plate, with the backside of the rib protruding toward the anode plate as the starting point. A lead storage battery having a curved arc shape.