Technical Field

The invention relates to the intercellular connection cables used in the batteries and providing the serial or parallel connection of the battery cells with each other.

Particularly, the invention is related to a method for producing the monotype flexible connection cable which provides the serial or parallel connection of the battery cells with each other by using the cable itself, without attaching the terminals or additional parts to both ends thereof, and also prevents the oxidation by sealing.

State of the Art

The traction batteries are the energy storage systems used in the mobile vehicles. The forklifts, carrying or lifting platforms, underground mining locomotives, airport vehicles, ground cleaning machines and electric vehicles are the most common areas where the traction batteries are used.

The traction batteries are generally obtained by placing the 2-volt cells in an open-top steel case with the acid-resistant coating and connecting the poles of these cells with each other via the conductive connection cables. A battery is obtained by connecting the 2-volt cells in series with the connection cables according to the desired voltage level. The traction batteries are generally produced in the range of 12 volts-96 volts and 150Ah-1500Ah.

In the state of the art, the cells of the traction batteries which can be designed according to the desired voltage and ampere values are connected with each other by using the flexible and non-flexible conductive connection elements.

The non-flexible connection elements are generally made of copper or lead bars. However, due to the non-flexible nature of said connection elements, the problems occur in adjusting the lengths of the cells in the installation, as well as the fractures due to the vibrations in the rough places during use. Due to these problems, the flexible connection elements produced from the multiple-wire copper cables have been started to be used instead of the non-flexible connection elements.

The flexible connection elements with the multiple-wire copper cables used in the traction batteries are manufactured in two ways.

In the first production method of the flexible connection cables, the cable is first cut to the appropriate length, and the cable insulation layer at the ends is stripped at the predetermined dimensions, revealing a multiple-wire structure at both ends. The terminals are connected to the ends of the multiple-wire structure by using various welding methods and the mounting holes are drilled. Afterwards, a flexible connection cable is obtained by covering the insulation layer onto this structure by means of the plastic injection method. In the flexible connection cables produced by using the welding method, the terminals attached by the welding method may break off from the welding points in time. This break causes a fire as a result of the short circuit of the cable end. In addition, there is an additional cost in terms of labor and raw materials due to the use of the terminal and the welding process applied.

Some of the welding methods used in the production method of the flexible connection cables are the ultrasonic metal welding technology and resistance welding method.

The non-ferrous metals are joined by the ultrasonic metal welding technology. In the ultrasonic metal welding technology, with the horn made depending on the design of the product, the friction is created by creating 20.000 or 40.000 ultrasonic vibrations per second on the product, and by melting the metals, they are adhered to each other under pressure.

In another method, the resistance welding method, the MFDC (medium frequency DC) welding method is used, which is a new technology different from the classical resistance welding technique in the copper cable welding. The thermal deformation and welding corrosion are at a minimum level in the direct current (DC) welding by converting the 50-Hz city electricity to the 1000-Hz medium frequency with the help of an inverter and rectifying it with a diode group. In this way, the deformation of the cables and burns on the weld are prevented. The resistance welding method is carried out in two steps and the first step is ironing the material and the second step is boiling it. In fact, the so-called ironing process is preliminary for a standard welding process. At the beginning of the welding, the part is made ready for the welding process with the pre-current and the ironing is carried out, and the part structure is integrated and becomes a flat structure. Afterwards, in order to carry out the welding step by supplying the main current, the welding process is carried out by keeping the electrodes closed for a while, keeping the part under pressure for a short time after welding and then opening it.

In the second production method of the flexible connection cables, the cable is cut to the appropriate length and the cable insulation layer at the ends is stripped at the predetermined dimensions and a multiple-wire structure is revealed at both ends. The additional pieces of the suitable dimensions are engaged onto the said multiple-wire structure and the additional pieces are crushed to the appropriate thickness under the press. The mounting holes are drilled on the additional parts on the multiple-wire structure obtained by crushing under the press, and a flexible connection cable is obtained as a result of coating the insulation layer on this structure by using the plastic injection method. Although no welding method is used in the aforementioned production method, it increases the cost due to the high cost of the additional parts and labor in the production method.

In the research in the literature, the document no. CN209249566 can be shown as an example of the state of the art. The aforementioned document is related to the battery connection cable. In the present invention, both ends of the connection wire are covered with a rubber sleeve and a hole is formed thereon. There is a groove in the inner wall of the hole and a connection part in the groove. The cost of the battery connection cable is high due to the aforementioned connection part.

In the present applications, a need for a flexible connection cable has occurred, which prevents the terminals of the flexible connection elements used in the traction batteries obtained by the aforementioned production methods from breaking off from the welding points, reduces the raw material and labor costs and also allows the battery cells to be flexibly connected with each other in parallel or in series.

As a result, the existence of the above problems and insufficiency of the existing solutions made it necessary to make an improvement in the related technical field. Object of the Invention

The present invention relates to a monotype flexible connection cable which eliminates the above-mentioned disadvantages and brings the new advantages to the related technical field.

The main object of the invention is to obtain a monotype flexible connection cable which provides the serial or parallel connection of the battery cells with each other by using the cable itself, without attaching the terminals or additional parts to both ends thereof, and also prevents the oxidation by sealing.

The object of the invention is to eliminate the need for the terminals connected to the ends of the flexible connection cable by the welding method and consequently the risk of fire caused by the short circuit as a result of the breakage of the terminals.

Another object of the invention is to eliminate the need for the additional parts connected to the ends of flexible connection cables by the pressing method.

Another object of the invention is to reduce the production costs arising from the production methods of the flexible connection cables.

Another object of the invention is to reduce the cost of the flexible connection cables.

The invention is related to a method for producing the monotype flexible connection cable which is used in batteries and provides the serial or parallel connection of the battery cells with each other, in order to fulfill all the above-mentioned objects resulting from the detailed description, and the method comprises the process steps of: a) obtaining a multiple-wire structure consisting of at least one wire by combining the wires of the appropriate cross-sections and covering the cable insulation layer onto the multiple-wire structure, b) stripping the cable insulation layer at least one end of the multiple-wire structure consisting of at least one wire at the defined dimensions, c) converting at least one end of the multiple-wire structure consisting of at least one wire into an ironed mono-structure by using the ironing process of the welding method, d) drilling the mounting hole on at least one of the ironed mono-structures.

The structural and characteristic features and all the advantages of the invention will be understood more clearly thanks to the figures given below and the detailed description referring to these figures. Therefore, the evaluation should be made by taking these figures and detailed description into consideration.

Brief Description of Drawings

Figure 1 is the view of the multiple-wire structure and insulation layer of the method for producing the monotype flexible connection cable according to the invention.

Figure 2 is the peeled view of the cable insulation layer at both ends of the multiple- wire structure of the method for producing the monotype flexible connection cable according to the invention.

Figure 3 is the ironed mono-structure view of both ends of the multiple-wire structure of the method for producing the monotype flexible connection cable according to the invention.

Figure 4 is the view of the ironed mono-structure, having the drilled holes and the cut edges, of the method for producing the monotype flexible connection cable according to the invention.

Figure 5 is the final view of the ironed mono-structure, which is covered by the sealing caps, of the method for producing the monotype flexible connection cable according to the invention.

Reference Numeral List

10. Monotype flexible connection cable

11. Multiple-wire structure

12. Insulation layer

13. Ironed mono-structure

14. Mounting hole

15. Sealing cap

Detailed Description of the Invention In this detailed description, the preferred alternatives of the method for producing the monotype flexible connection cable (10) according to the invention are explained only for a better understanding of the subject and without any restrictive effect.

The invention relates to a method for producing the mono-type flexible connection cable (10) which is used in batteries and provides the serial or parallel connection of the battery cells with each other.

The method for producing the monotype flexible connection cable (10) according to the invention is as follows:

As seen in Figure 1, the multiple-wire structure (11) is obtained by combining the wires of the appropriate cross-sections, and the cable insulation layer (12) is covered onto the multiple-wire structure (11) by the extrusion method. The multiple-wire structure (11) may consist of at least one wire.

As seen in Figure 2, the cable insulation layer (12) at least one end of the multiple-wire structure (11) is stripped at the defined dimensions.

As seen in Figure 3, at least one end of the multiple-wire structure (11) is converted into an ironed mono-structure (13) by using the ironing process of the resistance welding method.

As seen in Figure 4, the mounting hole (14) is drilled on at least one of the ironed mono-structures (13). In an alternative embodiment of the invention, the edges of the ironed mono-structure (13) can be cut into the oval or rectangular shape.

As seen in Figure 5, the sealing caps (15) are covered onto the ironed mono-structure (13) by the plastic injection method and the monotype flexible connection cable (10) is obtained.