JPS5832740B2 - Connection method between storage battery cells - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method for connecting cells in a storage battery, in which connecting bodies for adjacent cells are respectively located on both sides of a through hole provided in a battery case partition, and a connecting body is provided in one connecting body. The protrusion
A substantially wedge-shaped self-heating pressure piece that also serves as an energizer is inserted from the outside of the other connection body by penetrating the partition wall through-hole and facing the other connection body, and applying pressure to this opposing portion with a pair of pressure pieces. It is an object of the present invention to weld opposing portions on the outside of the through hole by pressurizing and heating with an electrode, thereby making it possible to obtain a highly reliable intercell connection structure with improved workability.

Conventionally, this type of cell-to-cell connection method involves inserting protrusions provided on the connection bodies of adjacent cells into the partition wall through-holes, abutting them, and applying current while applying pressure to melt the abutted portions due to resistance heat generation. Connection can be made by welding by welding, or by passing a protrusion provided on one cell connection body through the partition wall through-hole and the through-hole provided on the other connection body, and caulking the tip of the protrusion to the periphery of the through-hole of the other connection body. Methods were taken to do so.

However, the former method is electric resistance welding that uses Joule heat, and as this Joule heat is generated inside the partition wall through-holes, the partition wall through-holes are damaged by heating, worsening the airtightness of the connection part, and the partition wall It has the disadvantage of deteriorating the mechanical strength of the through-hole part, and the quality of the welding condition cannot be determined by visual inspection.

- Although the latter method does not cause damage to the partition wall through-holes, it has the disadvantage that it requires a hot wire during the caulking process and the work is complicated because it is fixed by caulking.

The present invention is a connection method capable of eliminating such conventional drawbacks and providing an intercell connection structure with good workability and excellent reliability, and examples thereof will be described below.

In FIG. 1, 1 is a battery case, 2 is a partition wall thereof, and a through hole 3 is provided for connection between cells.

Reference numerals 4 and 5 denote inter-cell connectors provided between two adjacent cells 6 via a partition wall, and the width thereof is larger than the diameter of the through hole 3 of the partition wall.

One of the connecting bodies 4 is provided with a projection 7 having a smaller diameter than the through hole 3 in the partition wall and tapered so that the tip becomes slightly thinner. and faces the other connecting body 5.

Reference numerals 8 and 9 denote a pair of pressurizing pieces that pressurize the connecting bodies 4 and 5 toward the partition wall, and one pressurizing piece 9 substantially serves as a pressurizing piece that pressurizes the connecting body 5 and also serves as a substantially wedge for energization. It has a shaped electrode 10.

This abbreviation (rust-shaped electrode 10) is made of a heat-resistant material that can withstand self-heating. It is made of a material that meets these requirements, such as chromium plated with copper, tungsten, or super hard graphite.

Therefore, in the substantially wedge-shaped self-heating pressurizing piece/current-carrying electrode 10, the internal resistance of the electrode itself is greater than the contact resistance with the connecting body 5, and the contact resistance between the connecting body 5 and the electrode 10 is larger. Heat generation begins at the contact portion of the connecting body 5, and when the connecting body 5 melts and softens, an arc is generated and the molten lead is prevented from being blown away.

By the way, the contact resistance between the connecting body 5 and the electrode 10 is 0.007.
Ω, whereas the internal resistance of the electrode is 0.05Ω.

Reference numeral 11 denotes a ring-shaped protrusion that is concentric with the protrusion 7 and the protrusion provided on the other connecting body 5 facing the protrusion 7, has a larger diameter than the through hole 3, and is formed on one side facing the partition wall 2. has been done.

Reference numeral 12 denotes a conductor piece provided on the approximately wedge-shaped pressure piece/current-carrying electrode 10, which is connected to a low voltage, high current power source 13, and during welding, a voltage of 6 cm and a current of 9,000 to 10,000 A are applied for a short time.

14 is a heat-resistant insulator that protects the electrode 13 from the pressing jig 9.

In the state shown in FIG. 1, pressurizing jigs 8 and 9 are lightly pressed in the direction of the partition wall 2 to bring the connecting bodies 4 and 5 into close contact with the partition wall 2,
By pressurizing the approximately wedge-shaped electrode 1o to the connecting body 5,
The pressure applied to the pressure jigs 8 and 9 increases.

Fluctuations in the electrode due to this pressure increase are detected by, for example, a pressure detector, and when a specified pressure value due to this fluctuation is reached, the power supply switch of the power source 13 is turned on.

When the switch of the power source 13 is turned on, a voltage of 6 cm and a voltage of R9ooo to 1oooA are applied to the electrode 10.

As a result, the electrode 10 itself generates heat, and the electrode 10 of the connecting body 5
The pressurized portion is heated and melted, and the protrusion T is also heated by the entrance of the electrode 10, and the molten lead melts together to form welding.

At this time, the current flows through the path of the conductor piece 12 → wedge-shaped electrode 10 → connection body 5 → pressurizing piece 9 as shown by the arrow, and the current flow time can be as short as about 3 seconds, due to heat generation. After that, even if the electricity is turned off, both the connecting bodies 4 and 5 are pressed toward the partition wall 2 by heating and melting and by the pressure applied by the pressure piece 89, and the state in which the ring-shaped protrusion 11 is bitten into the partition wall 2 is maintained. Therefore, liquid tightness can be sufficiently ensured.

FIG. 2 shows the inter-cell connection portion which has been welded in this way, and a substantially wedge-shaped recess 15 is formed in one of the connecting bodies 5 as a residue left by the substantially wedge-shaped electrode 10 biting into it.

As described above, the cell-to-cell connection of the present invention is achieved by generating heat from the substantially wedge-shaped self-heating pressure piece and current-carrying electrode outside the through-hole of the partition while a pair of connecting bodies is pressed against the partition. Since welding is carried out by heating and melting the body, it is easy to determine whether the weld is good or bad by visual inspection, and there is little chance that heating will have an adverse effect on the partition wall during welding.

Therefore, one of the intercell connectors needs a protrusion that penetrates the partition wall hole and projects to the other, but the part of the other connector that faces the protrusion may be flat or recessed. Welding can be performed without any problems.

Further, by heating and melting the connecting body after the connecting body is pressurized against the partition wall, the connection can be completed while reliably maintaining the liquid tightness of the inter-cell connecting portion.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an inter-cell connection of a storage battery according to an embodiment of the present invention, and FIG. 2 is a sectional view of the inter-cell connection after welding has been completed. 1...Battery case, 2...Bulkhead, 3...
...Through hole, 4,5...Connection body, 6...
Cell, 7... Protrusion, 8, 9... Pressure piece, 10... Approximately wedge-shaped self-heating pressure piece/current-carrying electrode, 11... ...Ring-shaped protrusion.

Claims (1)

[Claims] 1. Positioning the connecting bodies of adjacent cells on both sides of the through-hole provided in the battery case partition wall, making the protrusion provided on one connecting body pass through the through-hole of the partition wall and facing the other connecting body, In the method of welding the opposing portions outside the through hole by heating the opposing portions with electricity from the outside of the other connecting body while the opposing portions are pressurized by a pair of pressurizing pieces, one of the opposing portions that is in contact with the other connecting body The pressurizing piece is equipped with a substantially wedge-shaped self-heating pressurizing piece and energizing electrode separated by a heat-resistant insulator, and is configured to start energizing when the electrode changes due to pressurization. A method for connecting cells in a storage battery.