JPH079801B2 - Lead-acid battery inter-cell connection method - Google Patents

Description

Description: [Industrial application] The present invention relates to a method for connecting cells of a lead storage battery.

[Prior Art] As a method for connecting cells of a lead storage battery, there is a method as disclosed in, for example, JP-A-62-26146. In the conventional method as shown in the publication, first, a connecting through hole is formed by forming an inter-cell connecting portion of a pair of cells adjacent to each other with a non-conductive partition wall partitioning the inside of the battery case formed in the non-conductive partition wall. Place them so that they face each other. Then, by a clamp device having a pair of electrodes, the pair of electrodes are pushed out into the through hole for connection from the both sides of the pair of electrodes so that parts of the pair of inter-cell connecting portions are brought into contact with each other. Next, while the clamping force (pushing force) of the clamping device is kept constant, the pair of electrodes are energized to melt the contact portions of the pair of inter-cell connecting portions. Then, after filling the connection through hole with the molten lead alloy, the energization of the pair of electrodes is stopped to solidify the molten lead alloy, thereby connecting the cells of the lead storage battery.

[Problems to be Solved by the Invention] In the conventional method, the clamping force is kept constant even after the power supply to the electrodes is stopped. When the molten lead alloy solidifies, volume contraction always occurs. When volume contraction occurs, solidification cracking easily occurs in the solidified molten lead alloy, and this solidification crack causes liquid leakage and has a problem of adversely affecting the electrical connection between both cells.

An object of the present invention is to provide a method capable of connecting cells of a lead storage battery so that solidification cracking does not occur as much as possible when the molten lead alloy is solidified.

[Means for Solving the Problem] In the method of the present invention, the clamping force of the clamping device is increased after the energization of the pair of electrodes is stopped and before the molten lead alloy is solidified.

[Operation] It was also considered to increase the clamping force when energizing a pair of electrodes, but the clamping force (extrusion pressure) during welding is the electrode follow-through (following property) that accompanies the melting of the lead alloy during welding. ), There is a proper clamping force.
Therefore, the clamp cannot be increased unnecessarily when the electrodes are energized. On the other hand, after the energization is stopped, it is not affected by the welding condition. Therefore, in the present invention, after the energization of the pair of electrodes is stopped and before the molten lead alloy is solidified, the clamping force of the clamping device is increased to further push a part of the inter-cell connecting portion into the connecting through hole. By inserting
It compensates for the volume shrinkage that occurs during solidification. This allows
The rate of solidification cracking is significantly reduced.

Embodiment An embodiment of the method of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic structure of an example of an apparatus for carrying out the method of the present invention. In this figure, in the clamp device 1 including the pair of electrodes 2a and 2b, only the conductive electrode holders 3a and 3b holding the pair of electrodes 2a and 2b and the diaphragm cylinder 4 used as a driving means thereof are provided. It is shown. A welding power source 5 is provided on the pair of electrode holders 3a and 3b.
The secondary output of is connected. Although details of the power transmission mechanism 6 between the diaphragm cylinder 4 and the electrode holders 3a and 3b are omitted, the power transmission mechanism 6 is formed by the movement of the piston rod 4a of the diaphragm cylinder 4 and the electrode holder.
The tips of the electrodes 3a and 3b to which the electrodes 2a and 2b are attached are configured to move toward and away from each other. The diaphragm cylinder 4 has a well-known structure, and the piston rod 4a moves in one direction along with the movement of the diaphragm 4b by the air pressure, and when the air pressure is lost, the piston rod 4a returns to its original position by the spring 4c. Have

In FIG. 1, 7 is a drive air supply control device for supplying drive air to the diaphragm cylinder 4. This device is provided with a service tank 8, a regulator 9 and a reverse drive device via an air supply pipe line. The stop valve 10 and the solenoid valves 11 and 12 are connected as shown in the figure.
The service tank 8 has a constant pressure (5.5 kg / cm in this embodiment).
² ) Air is supplied, and the regulator 9 reduces the air pressure from the service tank 8 to a predetermined pressure (4.0 kg / cm ² in this embodiment). Solenoid valve 11
Is provided in order to control the supply of air to the diaphragm cylinder 4 by disposing a valve element in the air supply conduit. In this embodiment, the solenoid valve 11 has a function of releasing air from the cylinder chamber of the diaphragm cylinder 4 when the supply of air to the diaphragm cylinder 4 is stopped. The air can be discharged from the cylinder chamber of the diaphragm cylinder 4 by using other valve means which is interlocked with the driving of the solenoid valve 11. The solenoid valve 12 is a valve that is opened when the air pressure of the service tank 8 is supplied to the diaphragm cylinder 4, and the check valve 10 is for preventing backflow of air when the solenoid valve 12 is opened. It is provided.

The structure of the connecting portion between the cells is as shown in the enlarged sectional view of FIG. In FIG. 2, reference numeral 13 is a hard insulating pad, and the pair of electrodes 2 a and 2 b extend so as to penetrate the insulating pad 13. Reference numeral 14 is a non-conductive partition wall for partitioning a battery case (not shown), 14a is a through hole for connection, and 15 and 16 are inter-cell connection portions of a pair of cells arranged with the partition wall 14 interposed therebetween.

Next, the case where the method of the present invention is carried out using the apparatus shown in FIG. 1 will be described. First, the inter-cell connecting portions 15 and 16 of a pair of cells that are adjacent to each other with the partition wall 14 interposed therebetween are arranged so as to face each other on both sides of the connecting through hole 14a formed in the partition wall 14, and the connecting portion is shown in FIG. The electrodes 2a and 2b of the clamping device 1 as shown
Place between. Next, with the solenoid valve 12 closed, the solenoid valve 11 is opened, and the air in the service tank 8 whose air pressure has been reduced to 4.0 kg / cm ² by the regulator 9 is supplied to the cylinder chamber of the diaphragm cylinder 4. The diaphragm cylinder 4 is driven by the supplied air pressure, the piston rod 4a moves according to the air pressure, and the electrode holders 3a and 3b move toward each other. Along with the movement of the electrode holders 3a and 3b, the electrodes 2a and 2b are connected to the inter-cell connecting portions 15 and 16 by a force corresponding to the air pressure.
Are extruded into the connecting through hole 14a so that they are brought into contact with each other. FIG. 3 shows the state at this time.

As shown in FIG. 3, with a part of the inter-cell connecting portions 15 and 16 in contact with each other, a predetermined welding current is applied from the power source 5 to the electrodes 2a and 2b through the electrode holders 3a and 3b. Resistance welding. Since the solenoid valve 11 is still open at this time, the electrodes 2a and
2b presses the inter-cell connecting portions 15 and 16 with a constant force.
Therefore, the distance between the electrodes 2a and 2b becomes shorter than that in the state shown in FIG. By applying welding current, the cell connection parts 15 and 16
After melting the lead alloy in the vicinity of the contact portion to fill the through hole 14a with the molten lead alloy, the welding current is stopped. The solenoid valve 12 is opened at the same time as or slightly later than the stop of energization, and the high air pressure of the service tank 8 is supplied to the diaphragm cylinder 4. Air pressure in the cylinder chamber is 4.0kg / cm
^{When the} pressure is increased from ² to 5.5 kg / cm ² , the clamping force of the clamping device 1 is correspondingly increased and the pushing force of the electrodes 2a and 2b is increased, so that the electrodes 2a and 2b become A part of it will be pushed further into the connecting through hole 14a. As a result, it is possible to compensate for the volume shrinkage that occurs when the molten lead alloy solidifies.

The solenoid valves 11 and 12 are closed after a lapse of a predetermined time from the stop of energization to the solidification of the molten lead alloy. When the solenoid valve 11 is closed, air is released from the cylinder chamber of the diaphragm cylinder 4, and the clamp device 1
The clamp is released and the welding operation ends.

When welding was carried out by the method of this example, it was confirmed that solidification cracking of 0.6% in terms of melting volume ratio could be prevented by 90% or more.

In the above embodiment, the clamp pressure of the clamp device is changed by using the air pressure, but the method of the present invention is not limited to the case of using the air pressure, and the clamp used in the known clamp device is used. Of course, the variable pressure technique can be applied when implementing the method of the invention.
The method of the present invention is not limited to the case of using the clamp device of the illustrated embodiment, and any structure of clamp device can be used as long as the clamp pressure can be changed.

The amount of change in the clamp pressure may be determined in consideration of the material and thickness of the inter-cell connecting portion to be welded, the size of the connecting through hole, the welding current, etc., and is not limited to the embodiment.

EFFECTS OF THE INVENTION According to the present invention, after the energization of the pair of electrodes is stopped and before the molten lead alloy is solidified, the clamping force of the clamping device is increased to further connect a part of the inter-cell connecting portion. Since it is pushed into the through hole, the volume contraction that occurs during solidification can be compensated for, and solidification cracking can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an example of an apparatus for carrying out the method of the present invention, FIG. 2 is an enlarged sectional view showing a state of a connecting portion before extrusion, and FIG. 3 is a state of a connecting portion after extrusion. It is an expanded sectional view showing. 1 ... Clamping device, 2a, 2b ... Electrode, 3a, 3b ... Electrode holder, 4 ... Diaphragm cylinder, 5 ... Power supply, 6 ...
… Power transmission mechanism, 7 …… Drive air supply controller, 8
...... Service tank, 9 ...... Regulator, 10 ...... Check valve, 11,12 ...... Solenoid valve, 14 ...... Non-conductive partition wall, 14a ...... Connecting through hole, 15,16 ...... Cell connection section .

Claims (1)

[Claims] 1. An inter-cell connecting portion of a pair of cells that are adjacent to each other with a non-conductive partition wall interposed therebetween is disposed opposite to both sides of a connection through hole formed in the non-conductive partition wall, and a pair of electrodes is provided. A part of the pair of inter-cell connecting portions is pushed into the connecting through-hole by the pair of electrodes from both sides of the pair of inter-cell connecting portions by a clamp device, and the pair of inter-cell connecting portions are passed through the connecting through-hole. The pair of cell-to-cell connecting portions are clamped so as to partially contact in the holes, and the pair of electrodes are energized while the clamping force is kept constant to melt the contact portions of the pair of cell-to-cell connecting portions. Then, in the method of connecting between the cells of the lead acid battery by solidifying the molten lead alloy by stopping the energization to the pair of electrodes after filling the connection through hole by the molten lead alloy, the pair of electrodes After stopping the power supply to the A method for connecting cells of a lead storage battery, wherein the clamping force of the clamping device is increased before the molten lead alloy is solidified.