JP2014110129A - Electrode terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode terminal by which a fastening torque of a nut can be set high.SOLUTION: An electrode terminal used for a battery having a pair of output ends formed of metals different from each other, comprises: a first connector 10 having a male screw 2 screwed into a nut 200, and a shaft part 4 having a diameter smaller than that of the male screw 2; and a second connector 20 having a foundation part 21 always contacted with a flange 3 of the first connector 10. A material for the first connector 10 is set to carbon steel having a mechanical strength higher than that of the second connector 20, and the first connector 10 and the second connector 20 are unified. Thereby, because the material for the male screw 2 is wholly carbon steel, a fastening torque of the nut 200 can be set higher compared with the conventional art, and there is an advantage that the nut 200 is less likely to be loosened.

Description

  The present invention relates to an electrode terminal of a battery in which a positive electrode and a negative electrode are formed of different kinds of metals.

  A battery mounted in an electric vehicle or hybrid car has a plurality of battery cells connected, and the positive and negative electrodes of each battery cell are connected in series by a plate-shaped bus bar, enabling high-capacity power output. It is configured. In addition, the battery cell is a lithium ion battery, and the electrode terminals are generally made of aluminum with a positive electrode and copper with a negative electrode.

  Patent Document 1 is known as an electrode terminal of a battery cell composed of such a lithium ion battery. This conventional electrode terminal is composed of a mandrel part made of a solid shaft and an outer cylinder part inserted through the mandrel part, and the mandrel part and the outer cylinder part are each made of a different metal and They are joined and formed integrally. The mandrel part is arranged so as to project from the end surface of the outer cylinder part, and the projecting part is accommodated in the battery cell, while the outer cylinder part is arranged on the projecting side of the mandrel part. And a screw part into which a nut (not shown) can be screwed. That is, the battery is connected by the bus bar arranged on the negative electrode of the battery cell adjacent to the positive electrode of the battery cell, and since the bus bar is fixed by the nut and is in contact with the base portion, The battery cells are connected in series.

  According to Patent Document 1, in the case of a positive electrode, aluminum is used for the material of the mandrel part, and copper is used for the material of the screw part. On the other hand, in the case of the negative electrode, copper is used for the material of the mandrel part, and aluminum is used for the material of the screw part.

JP 2011-210481

  However, the conventional electrode terminal has a problem that the screw portion is easily broken when the nut is tightened because the material of the screw portion is set to copper or aluminum whose mechanical strength is lower than that of carbon steel. . Further, since it is necessary to increase the mechanical strength of the screw portion in order to eliminate the breakage of the screw portion, it is conceivable that the diameter of the screw portion is set to be large so as to cope with a high tightening torque. However, in this case, since the screw size of the screw portion cannot be reduced, there is a problem that the electrode terminal and the battery cannot be reduced in size.

  The present invention has been made in view of the above problems, and the present invention provides a male screw that is screwed to a nut and an electrode that is used for a battery in which a pair of output ends are formed of different metals. A first connection portion having a shaft portion having a smaller diameter than a screw; and a second connection portion having a base portion that is always in contact with the first connection portion, wherein the first connection portion is connected to the second connection. The material is set to a metal higher than the mechanical strength of the part, and the first connection part and the second connection part are integrated. In addition, it is preferable to set the said 1st connection part to carbon steel. The second connection part is preferably set to aluminum or copper. Furthermore, it is preferable that the first connecting portion and the second connecting portion are integrated by applying pressure to one end of the shaft portion of the first connecting portion by plastic deformation of the first connecting portion.

  In the electrode terminal 1 of the present invention, even when a nut is tightened on the male screw, the male screw is made of a material having high mechanical strength. There is an advantage to reduce. In addition, since the material of the second connection portion is set to aluminum if it is a positive electrode and copper if it is a negative electrode, the electrons in the battery move efficiently due to the characteristics of these materials and can output high power. There are also advantages. Furthermore, the first member and the second member are integrated by plastically deforming one end of the shaft portion by a press machine, so that the first member and the second member are compared with, for example, joining such as welding or spin caulking. The joining time of the member and the second member is shortened. Therefore, the electrode terminal 1 of the present invention has an advantage that productivity can be improved as compared with the conventional case.

It is a perspective view which shows one Example of this invention. It is sectional drawing which shows the use condition of FIG. It is explanatory drawing which shows the assembly process of FIG. Moreover, (a) is explanatory drawing which shows the process at the time of assembling FIG. 1, (b) is explanatory drawing which shows the process at the time of integrating (a), (c) is the process of (b). It is explanatory drawing which shows the state which completed.

  Hereinafter, the electrode terminal of the present invention will be described with reference to FIGS. The electrode terminal 1 of the present invention includes a first connecting portion 10 having a male screw 2 that can be screwed into a nut 200, and a second connecting portion 20 that holds the male screw 2 of the first connecting portion 10 so as to protrude. These are joined together and configured integrally.

  As shown in FIG. 3A, the first connection portion 10 has the male screw 2 disposed at one end thereof, and a shaft portion 4 having a diameter smaller than the diameter of the male screw 2 at the other end. It is arranged. Further, adjacent flanges 3 are arranged between the male screw 2 and the shaft portion 4, and the first connecting portion 10 integrally forms the male screw 2, the flange 3, and the shaft portion 4. Do it. Moreover, while the said flange 3 is formed in the square which is an example of polygonal shape as shown in FIG.1 and FIG.2, the said axial part 4 is formed in the column shape.

  The first connecting part 10 is made of carbon steel, which is a material with high mechanical strength. In this embodiment, carbon steel for cold heading (SWCH material) that is often used for thread rolling. Is set to That is, each of the first connecting portions 10 is integrally formed by cold forging, and the male screw 2 in this embodiment is formed by rolling, which is a general processing of male thread forming. Yes. In addition, although the process of the said external thread 2 was rolled, it is good also as a cutting process.

  On the other hand, the second connection portion 20 includes a base portion 21 formed so as to be able to fit the flange 3 and a cylindrical portion 22 protruding from the base portion 21. In addition, a flange fitting hole 23 that fits into the flange 3 is disposed on the end surface of the base portion 21, while the end surface of the cylindrical portion 22 is illustrated in FIGS. 3B and 3C. A tool insertion hole 25 into which the illustrated press tool 300 can be inserted is arranged. Further, the flange fitting hole 23 and the tool insertion hole 25 are connected by a shaft portion insertion hole 24 into which the shaft portion 4 can be inserted, and the second connection portion 20 is connected to the first connection portion 10. It is configured to be hollow so that it can be inserted.

  In the present embodiment, the material of the second connecting portion 20 is set to either aluminum or copper. This is because the electrode terminal 1 of the present invention is used as an electrode of a battery cell which is a lithium ion battery as described above. For example, the material of the second connection portion 20 is set to aluminum when it is arranged on the positive electrode side, and is set to copper when it is arranged on the negative electrode side.

  That is, if the electrode terminal 1 of the present invention is a positive electrode, the material of the second connection part 20 is aluminum, and the material of the first connection part 10 is set to carbon steel, while the material of the first connection part 10 is second if it is a negative electrode. The material of the connection part 20 is copper, the material of the 1st connection part 10 is set to carbon steel, and two types exist.

  Thus, since the said 1st connection part 10 and the 2nd connection part 20 consist of a respectively different metal, each is shape | molded through a separate processing process. After passing through these separate processing steps, the first connection portion 10 and the second connection portion 20 are joined and integrated, respectively. This joining will be described below with reference to FIGS. 3 (a) to 3 (c).

  First, as shown in FIG. 3A, the shaft portion 4 of the first connecting portion 10 is set facing upward. Next, the shaft 4 is covered with the second connecting portion 20 and set so that the flange fitting hole 23 is fitted to the flange 3. Thereby, at least the end surface of the flange 3 and the bottom surface of the flange fitting hole 23 come into contact with each other, and the state shown in FIG. 3B is obtained, and one end of the shaft portion 4 projects from the shaft portion insertion hole 24. One end of the shaft portion 4 is pressed by a press tool 300 set in a press machine (not shown) and is plastically deformed to increase its diameter as shown in FIG. To spread. Thereby, the first connection part 10 and the second connection part 20 are joined together.

  The completed electrode terminal 1 of the present invention is attached so that the cylindrical portion 22 of the second connection portion 20 is positioned inside the battery cell, and the outer side of the first connection portion 10 is outside the battery cell. The screw 2 and the base portion 21 of the second connection portion 20 are attached so as to protrude.

  In addition, as shown in FIG. 2, the electrode terminal 1 is inserted through the male screw 2 and a bus bar 100 arranged so as to come into contact with the base portion 21 is fixed by a nut 200, and the electrode of the adjacent battery cell Connected to terminal 1. Therefore, since the positive electrode of the battery cell and the negative electrode of the adjacent battery cell are connected by one bus bar 100, a plurality of battery cells are connected in series by fastening the nut 200 to the bus bar 100. .

  As described above, the electrode terminal 1 of the present invention has an advantage that the nut 200 can be fastened with a tightening torque higher than that of the related art since the male screw 2 is set to carbon steel having high mechanical strength. For this reason, it becomes difficult to loosen the nut 200, and it is possible to reduce the breakage of the threaded portion as in the conventional case. In addition, since the flange 3 has a quadrangular shape and the flange 3 is fitted in the flange fitting hole 23, the first connection portion 10 is loaded with a high tightening torque. The connection part 10 also has an advantage that it does not idle. Furthermore, in the electrode terminal 1 of the present invention, since all the male screws 2 are the above-described carbon steel, the diameter of the screw portion that receives a high tightening torque as in the conventional case can be set smaller than in the conventional case. Thereby, the electrode terminal 1 of this invention also has the advantage which can be reduced in size and weight compared with the past. Further, since the first connecting portion 10 and the second connecting portion 20 are joined by the caulking tool 300, for example, it can be processed at a lower cost than joining such as welding or spin caulking, and productivity is higher than conventional. There is also an advantage to improve. The first connection part 10 may be subjected to a quenching process in order to further improve the mechanical strength. Further, as shown in FIGS. 2 and 3 (c), the end surface of the base portion 21 of the second connecting portion 20 projects from the boundary between the male screw 2 and the flange 3, but the male screw 2 and the boundary of the flange 3 do not have to protrude from the end surface of the base portion 21 and may be dimensioned on the same surface.

DESCRIPTION OF SYMBOLS 1 Electrode terminal 2 Male thread 3 Flange 4 Shaft part 10 1st connection part 20 2nd connection part 21 Base part 22 Tube part 23 Flange fitting hole 24 Shaft part insertion hole 25 Tool insertion hole 100 Busbar 200 Nut 300 Press tool

Claims (4)

In an electrode terminal used for a battery in which a pair of output ends are formed of different metals,
A first connection portion having a male screw to be screwed to the nut and a shaft portion having a smaller diameter than the male screw, and a second connection portion having a base portion that is always in contact with the first connection portion;
The material of the first connection part is set to a metal higher than the mechanical strength of the second connection part,
The electrode terminal, wherein the first connection portion and the second connection portion are integrated.   The electrode terminal according to claim 1, wherein the first connection part is set to carbon steel.   The electrode terminal according to claim 1, wherein the second connection portion is set to aluminum or copper.   The first connection part and the second connection part are integrated by applying pressure to one end of a shaft part of the first connection part by plastic deformation of the first connection part. The electrode terminal according to claim 3.

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