JPH09219186A - Equipment for connecting batteries - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an equipment for connecting batteries in order to constitute a combination battery having a large capacity and generating a predetermined output voltage by connecting several batteries together, and to reduce the contact resistance between a contact terminal plate and a collecting terminal without changing the size of an electrode pole of a battery. SOLUTION: A screw hole 32 and annular support grooves 31 are formed on a vertex surface of an electrode pole 16 of a battery, whereas a connection terminal plate 20 having projections 29 of shapes corresponding to that of the support grooves 31 in both end parts is equipped. After respectively fitting the projections 29 into the support grooves 29 of the electrode pole 16 of a battery, a fixing bolt is screwed into the screw hole 32 through the connection terminal plate 20, which is fixed to the electrode pole 16 so as to constitute an equipment for connecting between batteries.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery connecting device for connecting a plurality of unit cells (cells) having a limited terminal voltage or a limited capacity to obtain a predetermined voltage.

[0002]

2. Description of the Related Art Conventionally, a lead storage battery has been put into practical use as a large storage battery used in electric vehicles and the like. However, since the so-called energy storage density and cycle life are insufficient, in recent years, large nickel-hydrogen storage batteries having about twice the energy storage density and cycle life of lead storage batteries have been developed.

When this nickel-hydrogen storage battery is used as a power source for an electric vehicle, for example, 10 unit cells (cells) each having a voltage output of 1.2 V are connected in series to form one unit.
The module is configured to obtain an output voltage of 12V. In addition, a plurality of these modules are connected in series to serve as a drive power source for a traveling motor of an electric vehicle. In this case, for example,
24 modules are connected in series to obtain a driving voltage of 288V, or 11 modules are connected in series to obtain a driving voltage of 132V, and this driving voltage is output to a driving motor to drive an electric vehicle. .

Therefore, when the nickel-hydrogen storage battery is used as a power source for, for example, an electric vehicle, it is necessary to connect the unit cells in series and connect the modules in series. FIG. 4 is a schematic side view for explaining a connection state between the single cells in the conventional nickel-hydrogen storage battery, and FIG. 5 is an enlarged view of the right side terminal portion of FIG. As shown in both figures, the cells 1 and 2 are connected to each other on a current collecting terminal (for example, a positive electrode (+)) 1a of the cell 1 and a current collecting terminal (for example, a negative electrode (−)) 2a of the cell 2. The terminal board 3 is bridged, and the connection terminal board 3 is tightened and connected using bolts 4 and 5. That is, the two holes formed in the connection terminal plate 3 are placed on the upper surface of the current collector terminal 1a, which is the positive electrode of the unit cell 1, and the upper surface of the current collector terminal 2a, which is the negative electrode of the unit cell 2, so that they are aligned with each other. , The corresponding bolts 4 and 5 are tightened through the holes to electrically connect the collector terminals 1a and 2a with the connection terminal plate 3.
In both figures, the hexagon nuts 6 and 7 are nuts for attaching the respective collector terminals 1a and 2a to the unit cells 1 and 2. A washer 8 interposed between the bolts 4 and 5 and the connection terminal plate 3 is a washer with a claw having a rotation stopping function.

In order to show this state in more detail, FIG. 6 is a sectional view showing a connection relationship between the collector terminal 2a and the connection terminal plate 3. As shown in the figure, the holes 9 provided in the connection terminal plate 3
A bolt 5 is inserted in the bolt 5 and the upper surface 2a ′ of the pole 2a and the lower surface of the connection terminal plate 3 are pressed by the bolt 5 to electrically connect the unit cell 2 and the connection terminal plate 3. Therefore, the collector terminal 2a
An electric current flows through the pressure contact portion 10 between the upper surface 2a ′ of the above and the connection terminal plate 3.

Although not shown, the modules are connected to each other in substantially the same structure, and the modules are connected via a connection terminal plate (not shown).

[0007]

In the conventional inter-battery connecting device, when electric power is taken out from the unit cells 1 and 2, between the current collecting terminal 1a and the connecting terminal plate 3, and between the current collecting terminal 2a and the connecting terminal plate 3.
A voltage drop occurs due to the connection resistance. For this reason, the required output voltage cannot be obtained, and unnecessary energy is consumed due to the power consumption due to the connection resistance, and in addition, heat is generated and the function of the unit cell itself is impaired. Therefore, it is necessary to keep the connection resistance as small as possible.

By the way, the connection terminal plate 3 is the collector terminal 1
The contact terminals 1a, 2a and the connection terminal plate 3 are pressure-contacted with each other, and the contact is at the connection portion 10, and the connection area is extremely narrow as shown in FIG. That is, a hole 9 through which the bolt 5 penetrates is formed in the connection terminal plate 3, and moreover, the bolt 5 can penetrate the hole 9 with a margin.
Since the diameter of the hole 9 is made large to some extent, the collector terminal 1
The connection portion 10 between the upper surfaces of the a and 2a and the connection terminal plate 3 has an extremely narrow area. Therefore, the connection resistance at the connection portion 10 also becomes large, and when it is mounted on an electric vehicle, a module is constructed by connecting 10 unit cells (cells) in series, and further, for example, 24 modules are connected in series. Must be connected and used. For this reason, the above-described connection structure is used at a large number of locations, and the electrical resistance is as large as several tens of times or several hundred times the connection resistance at one location. Therefore, the voltage drop becomes large due to the increase in the connection resistance, and there arises a problem such as a decrease in the battery voltage at the time of high rate discharge.

In the above case, it is conceivable that the current collecting terminals 1a, 2a have a large diameter to increase the contact area with the connection terminal plate 3, but in this case, the hexagon nuts 6, 7 etc. are made large. It is also necessary and cannot be done freely due to dimensional constraints. Further, since the alkaline solution is enclosed in the battery, the pH of the alkaline solution is about 16, that is,
Since an electrolytic solution having a basicity close to 100% is used, it is necessary to use nickel or an equivalent metal material that is not easily corroded by the above-described electrolytic solution as a material for the current collecting terminals 1a and 2a.
For this reason, the metal material for the current collecting terminal becomes a relatively expensive material, and it is required to keep the diameter and the length of the current collecting terminal to the necessary minimum size, which is also subject to dimensional restrictions.

The present invention is a battery capable of reducing the connection resistance between a connection terminal plate and a current collecting terminal without changing the diameter or length of the current collecting terminal, that is, without changing the outer dimensions of the current collecting terminal. An inter-connection device is provided.

[0011]

According to the present invention, the above-mentioned problems correspond to a current collecting terminal connected to an electrode plate of a battery and having a screw hole and a receiving groove formed on the top surface of the battery, and the shape of the receiving groove. A protrusion formed in a shape, a connection terminal plate having a hole, and a screw hole of the current collector terminal screwed through the hole of the connection terminal plate, and the protrusion of the connection terminal plate is received by the current collector terminal. This can be achieved by providing an inter-battery connecting device having a fixing bolt fitted in the groove.

The receiving groove formed in the current collecting terminal is, for example, an annular shape, and the projection formed on the connection terminal plate is an annular shape corresponding to the receiving groove.

With this structure, for example, a protrusion having the same shape formed on the connection terminal plate is fitted in the annular receiving groove formed on the top surface of the current collecting terminal of the unit cell or the module battery. Then, since the connection terminal plate is fixed to the current collecting terminal of the battery with the fixing bolt, the annular groove formed on the top of the current collecting terminal and the annular protrusion formed on the connection terminal plate are securely pressed against each other. At the same time, the electrical contact area between the collector terminal and the connection terminal plate can be increased.

That is, since the projection is closely fitted in the receiving groove, the contact portion between the side surface of the projection and the side surface of the receiving groove has a terminal portion of the battery as compared with the case where the projection is not provided. Contributes to an increase in the contact area at
A reduction in contact resistance can be realized. Therefore, the connection resistance between the contact terminal plate and the current collecting terminal can be reduced without changing the dimensions of the current collecting terminal or the like that comes into contact with the contact terminal plate.

Therefore, the connection resistance when the batteries are connected in series becomes small, and even when a large number of unit cells or module batteries are connected in series, the electric resistance of the entire power supply device can be kept small.

The battery is, for example, a nickel-hydrogen storage battery, and a predetermined number (for example, 10) of nickel-hydrogen storage batteries are connected in series to form a module battery. ) By connecting in series, it can be used as a drive source for a motor or the like, for example, as a battery for driving an electric vehicle.

Further, the current collecting terminal is made of, for example, nickel or a nickel alloy, and is constructed so as not to corrode the alkaline solution filled in the nickel-hydrogen storage battery.

[0018]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 2 is a configuration diagram of a single nickel-hydrogen storage battery (single battery) used in the description of the battery connecting device of the present embodiment. In the battery case of the unit cell 12, positive electrode plates 14 and negative electrode plates 15 are alternately arranged in the alkaline solution via the separators 13. The current collecting terminal 16 is attached to the lid 12 ′ of the unit cell 12, and the above-described many positive electrode plates 14 are attached to the lower portion of the current collecting terminal 16 by a method such as arc welding. Similarly, the current collecting terminal 17 is also attached to the lid 12 ′ of the unit cell 12, and the plurality of negative electrode plates 15 described above are provided below the current collecting terminal 17.
Is attached by a method such as arc welding. Therefore, the current collecting terminal 16 constitutes a positive electrode, the current collecting terminal 17 constitutes a negative electrode, and an output voltage of about 1.2 V of the unit cell 12 is generated between the both poles 16, 17.

The liquid port plug 18 provided upright on the lid 12 'of the unit cell 12 is a plug used for replenishing the alkaline solution in the battery case. FIG. 3 is a diagram illustrating a configuration in which the unit cells 12 having the above-described structure are connected in series.
2 and the unit cell 19 are connected in series by a connection terminal plate 20. The current collecting terminal 16 of the unit cell 12 is the positive electrode as described above, and is connected to the current collecting terminal 21 which is the negative electrode of the unit cell 19 via the connection terminal plate 20.

As described above, a large number of positive electrode plates 14 are attached to the collector terminal 16 below the collector terminal 16. The collector terminal (polar column) 16 is attached to the lid 12 ′ of the unit cell 12 by the hexagon nut 22. The attached alkaline solution is sealed by an O-ring (not shown). The unit cell 19 side also has the same configuration, and the current collecting terminal (pole column) 21 is a hexagon nut 2
It is attached to the lid 19 ′ of the unit cell 19 by 3, and the alkaline solution inside is sealed by an O-ring (not shown).

The connection terminal plate 20 is fastened on the collector terminals 16 and 21 by fixing bolts 24 and 25,
Between the collector terminal 16 and the fixing bolt 24, and the collector terminal 21
The connection terminal plate 20 is fixed between the fixing bolt 25 and the fixing bolt 25. Further, the fixing bolts 24, 25 are provided with pawl washers 26, 27 for preventing loosening.

FIG. 1 (a) is a partially cutaway side view of the above-mentioned connection terminal board 20, and FIG. 1 (b) is a schematic sectional view of an essential part of the current collector terminal 16. 1A and 1B, the connection terminal board 20 is made of a copper material and is formed in a rectangular shape or an elliptical shape, and annular projections 29 are formed on both sides in the longitudinal direction thereof. The protrusion 29 may be formed integrally with the connection terminal board 20, or may be formed separately from the protrusion 29 by brazing. The connection terminal plate 20 on which the protrusion 29 is located is substantially concentric with the inner circle of the protrusion 29, and
A hole 30 having a diameter slightly smaller than the diameter of the inner circle of the protrusion 29 is formed. However, this hole 30 is a protrusion 29.
When the connection terminal board 20 and the connection terminal board 20 are integrally formed,
The diameter may be the same as the inner diameter of the protrusion 29 to form a communication hole having no step.

On the other hand, the current collecting terminal 16 is formed into a short columnar projection made of, for example, pure nickel or monel metal, Hastelloy alloy, Inconel alloy, or other nickel alloy, and the lower portion of the current collecting terminal 16 is the positive electrode plate 14 as described above. Connect to.

The projection 29 is provided on the top surface of the collector terminal 16.
An annular receiving groove 31 (when viewed from the upper surface) is formed so as to fit the side surface of the protruding body 29 and the side surface of the receiving groove 31 by tightly fitting the protruding body 29 in the receiving groove 31. The contact portion of 2 plays a role of increasing the contact area between the two as compared with the case where the protrusion 29 is not provided.

A screw hole 32 into which the fixing bolt 24 is screwed is formed concentrically with the receiving groove 31 in the current collecting terminal 16, and the screw groove 1 is formed on the outer wall of the current collecting terminal 16.
6 'is formed.

Next, when connecting the above-mentioned unit cells 12 and 19, with the above-mentioned structure, the projection 29 of the connection terminal plate 20 is fitted into the receiving groove 31 of each unit cell 12, 19 to be connected,
The fixing bolt 24 is screwed into the screw hole 32 through the hole 30 of the connection terminal plate 20 to firmly fix the connection terminal plate 20 to the current collector terminal 16. At this time, it is preferable to set the dimension of the protrusion 29 so that the protrusion 29 fits tightly into the receiving groove 31. That is, the protrusion 29 is closely fitted in the receiving groove 31. To this end, the protrusion 29 may be formed of a relatively soft metal material such as copper, and the protrusion 29 may be pressed into the groove 31. As a result, the side surface of the protrusion 29 and the receiving groove 3
The contact portion with the side surface of No. 1 contributes to an increase in the contact area at the terminal portions of the unit cells 12 and 19 as compared with the case where the protrusion 29 is not provided, and the contact resistance can be considerably reduced.

The shape of the protrusions 29 is not necessarily circular, but may be polygonal, such as square ring, triangular ring, star ring, and the like. That is, the protrusion 29,
The shape of the receiving groove 31 corresponds to the shape of the annular receiving groove 31 provided in the current collector terminal 16, and may be any shape that can be fitted into the receiving groove 31.

When the outer wall of the protrusion 29 is knurled, the side surface of the protrusion 29 and the side surface of the receiving groove 31 can be effectively brought into contact with each other. Further, when the protrusion 29 is fitted into the receiving groove 31, if the mercury is attached to the knurled portion of the protrusion 29 in advance and then fitted into the receiving groove 31, the contact resistance is reduced. There is an effect that can be done.

Further, in the above embodiment, the vertical cross section of the protrusion and the receiving groove is substantially rectangular, but the present invention is not limited to this, and other shapes such as an inverted triangle or a semicircle may be used. . In short, any shape may be used as long as it can increase the contact area and can be fitted.

Further, in the above description of the embodiment, the case where the unit cells are connected to each other has been described, but the same can be applied to the case where the modules are connected to each other. Alternatively, it can be applied to the connection from the battery to the outside.

[0031]

As described above in detail, according to the present invention, the contact terminal plate and the current collecting terminal can be connected to each other without changing the size of the current collecting terminal (pole) contacting the contact terminal plate. The contact area can be increased, and as a result, the connection resistance between the two can be reduced. Therefore, various characteristics such as the battery output voltage and the power supply capacity can be improved.

Further, since the receiving groove into which the projection is fitted is formed on the top surface of the current collecting terminal, the amount of nickel or nickel alloy used for the current collecting terminal can be saved accordingly.

[Brief description of drawings]

FIG. 1A is a partially cutaway side view of a connection terminal plate spanning between current collecting terminals of a single battery, and FIG. 1B is a schematic cross-sectional view of a main part of a current collecting terminal of a single battery.

FIG. 2 is a configuration diagram of a nickel-hydrogen storage battery unit (single battery) used in the description of the battery connecting device of the embodiment.

FIG. 3 is a diagram illustrating a configuration in which unit cells are connected in series.

FIG. 4 is a schematic side view illustrating a connection state between single cells in a conventional nickel-hydrogen storage battery.

5 is an enlarged side view of the right side terminal portion of FIG.

FIG. 6 is a diagram illustrating a narrow contact area between a current collector terminal and a connection terminal plate in the case of the conventional example.

[Explanation of symbols]

 12, 19 Unit cells 12 ', 19' Lid body 13 Separator 14 Positive electrode plate 15 Negative electrode plate 16, 17, 21 Current collecting terminal plate 18 Liquid port plug 20 Connection terminal plate 22, 23 Hexagon nut 24, 25 Fixing bolt 26, 27 Washer with claw 29 Projection body 30 Hole 31 Receiving groove

Claims (5)

[Claims] 1. A current collector terminal, which is connected to an electrode plate of a battery and has a screw hole and a receiving groove formed on the top surface thereof, a protrusion formed in a shape corresponding to the shape of the receiving groove, and a hole. A connection terminal plate; and a fixing bolt that is screwed into a screw hole of the current collecting terminal through a hole of the connection terminal plate to fit a protrusion of the connection terminal plate into a receiving groove of the current collecting terminal. An inter-battery connection device characterized by the above. 2. The inter-battery connecting device, wherein the receiving groove formed in the current collecting terminal is annular, and the protrusion formed in the connection terminal plate is annular corresponding to the receiving groove. 3. The battery connection device according to claim 1, wherein the battery is a nickel-hydrogen storage battery. 4. The battery connecting device according to claim 3, wherein the battery is a module battery in which a predetermined number of nickel-hydrogen storage batteries are connected in series. 5. The inter-battery connection device according to claim 3, wherein the pole column is made of nickel or a nickel alloy.