JP2003017032A - Battery pack manufacturing method and interconnecting terminal for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack manufacturing method capable of securely welding interconnecting terminals and electrode surfaces of the battery to each other without generating reactive current, and provide interconnecting terminal for the same. SOLUTION: The interconnecting terminal 2 is divided into several terminal pieces 2a, 2b, 2c and 2d. In the condition that a clearance 4 is interposed between the terminal pieces, a lower end of each terminal piece 2a, 2b, 2c and 2d is arranged in a seal body 1b of one unit cell 2. Each welding electrode 6 and 7 are made to abut on the terminal pieces adjacent to each other through the gap 4, and the current D is made to flow between the welding electrodes 6 and 7 to weld the battery interconnecting terminal 2 and the seal body 1b to each other. An upper part of each terminal piece 2a, 2b, 2c and 2d is fitted on a negative electrode can 1a of the other unit cell 1, and each welding electrode 6 and 7 are made to abut on the adjacent terminal pieces, and the current D is made to flow between the welding electrodes 6 and 7 to weld the battery interconnecting terminal 2 and the negative electrode can 1a to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an assembled battery manufactured by connecting a single cylindrical battery or the like in series using a battery connecting terminal, and a battery connecting terminal used therefor.

[0002]

2. Description of the Related Art As shown in FIG. 9, a conventional assembled battery includes an outer metal sealing body 1b which is a positive electrode terminal of a single battery 1 and an outer metal negative electrode can 1a which is a negative electrode terminal of another single battery 1. The metal inter-battery connection terminal 10 is interposed between and. Then, the inter-battery connection terminal 10 is series-spot welded to the sealing body 1b and the negative electrode can 1a, respectively,
The unit cells 1 are connected to each other and connected in series (for example, JP-A-59-224056).

That is, the inter-battery connection terminal 10 and the sealing body 1b
As an example of series spot welding between and,
, A pair of welding electrode rods 6 and 7 is pressed against the inter-battery connection terminal 10 from the same direction (upper side in FIG. 10), and a current D is passed between these welding electrode rods 6 and 7 to connect the batteries. The terminal 10 and the sealing body 1b are welded.

In this case, of the current D flowing from the welding electrode rod 6 to the inter-battery connecting terminal 10, the current (effective current) flowing out to the welding electrode rod 7 through the inter-battery connecting terminal 10 after flowing through the sealing body 1b. The inter-battery connection terminal 10 by D1
However, a part D2 of the current D flowing into the inter-battery connecting terminal 10 flows out to the welding electrode rod 7 without flowing into the sealing body 1b. This current (reactive current)
D2 does not contribute to welding between the inter-battery connection terminal 10 and the sealing body 1b, and the effective current D1 is equal to the existence of the reactive current D2.
And the inter-battery connection terminal 10 and the sealing body 1b cannot be welded sufficiently.

As a countermeasure against this, if the plate thickness of the inter-battery connection terminal 10 is reduced, the electric resistance of the inter-battery connection terminal 10 increases and the reactive current D2 decreases, and the effective current D1 increases correspondingly, and the battery current increases. Connection terminal 10 and sealing body 1b
However, the strength of the inter-battery connecting terminal 10 is reduced due to the reduced plate thickness.

On the other hand, the inter-battery connection terminal 10 and the sealing body 1b are secured by increasing the current D and relatively increasing the effective current D1 without reducing the plate thickness of the inter-battery connection terminal 10. However, the reactive current D2 is increased by the amount of the increased current D, resulting in a large amount of unnecessary power consumption. Moreover, the Joule heat also increases with the increase of the current D, and the battery connection terminal 1
There is a risk that the molten metal such as 0 or the sealing body 1b will be scattered, causing damage to the inter-battery connection terminals 10 and the sealing body 1b, or causing thermal deterioration of the unit cell 1.

Therefore, in order to reduce the reactive current D2 without reducing the plate thickness of the battery connecting terminal 10, the slit 11 is formed in the battery connecting terminal 10 as shown in FIGS. 11 and 12.
Is provided, and the pair of welding electrode rods 6 and 7 are pressed against the inter-battery connection terminal 10 so as to sandwich the slit 11,
Welding can be considered. In this case, as shown in FIG. 12, the reactive current D2 flows through the inter-battery connection terminal 10 so as to bypass the slit 11, so that the longer the current path, the larger the electric resistance and the smaller the amount of the reactive current D2. Become. As a result, the effective current D1 becomes relatively large, and the inter-battery connection terminal 10 and the sealing body 1b can be reliably welded.

[0008]

Even if the inter-battery connecting terminal 10 is provided with the slit 11, a certain amount of reactive current D2 will flow. Moreover, the effective current D1 and the reactive current D2 are
Since the ratio of V depends on the contact state between the welding electrode rods 6 and 7 and the inter-battery connecting terminal 10, the welding electrode rod 6 and the inter-battery connecting terminal can be reliably welded even when the reactive current D2 becomes large. The current D to 10 must be increased to some extent.

In this case, similarly to the above, the power consumption becomes large, and the molten metal such as the inter-battery connecting terminal 10 and the sealing body 1b is also scattered to cause damage to the inter-battery connecting terminal 10 or the like. The battery 1 may be deteriorated due to heat. Further, it is necessary to reduce the labor of manufacturing and managing the components of the assembled battery.

An object of the present invention is to ensure that the inter-battery connecting terminal and the electrode surface of the battery can be welded without generating a reactive current. Another object of the present invention is to reduce the labor for manufacturing and managing the components of the assembled battery.

[0011]

According to the method of manufacturing an assembled battery to which the present invention is applied, one side of a battery connecting terminal 2 is welded to an electrode surface 1b of one battery 1, and the battery connecting terminal 2 is connected. By welding the other side portion to the electrode surface 1a of the other battery 1, the batteries 1 and 1 are connected by the inter-battery connection terminal 2 and connected in series.

The battery connection terminal 2 is composed of a plurality of terminal pieces 2a.2.
The terminal piece 2a is divided into b, 2c, and 2d and is adjacent to each other.
-A gap 4 is interposed between 2b, 2c, and 2d, and each terminal piece 2a, 2b, 2c, and 2d bridges the electrode surface 1b of one battery 1 and the electrode surface 1a of the other battery 1. , Each terminal piece 2a, 2b, 2c, 2d is a battery 1.
It is arranged on one of the electrode surfaces 1a and 1b. Then, with the welding electrode rods 6 and 7 of the pair of welding electrode rods 6 and 7 applied to the terminal pieces adjacent to each other across the gap 4, a current D is passed between these welding electrode rods 6 and 7. As a result, each terminal piece 2a, 2b, 2c, 2d is connected to the electrode surface 1a
1b is welded respectively.

More specifically, the terminal pieces 2a, 2b, 2c, 2d of the inter-battery connection terminal 2 have the same shape. By interposing the inter-battery connection terminals 2 between the batteries 1 and 1, it is possible to form an assembled battery including at least two batteries 1.

The inter-battery connecting terminal of the present invention has one side portion welded to the electrode surface 1b of one battery 1 and the other side portion welded to the electrode surface 1a of the other battery 1. Then, the adjacent batteries 1 and 1 are connected and connected in series. The inter-battery connection terminal 2 includes a plurality of terminal pieces 2a and 2b.
-Divided into 2c and 2d, 2a between adjacent terminal pieces
With a gap 4 interposed between 2b, 2c, and 2d, and the electrode piece 1a of one battery 1 and the electrode surface 1a of the other battery 1 are bridged by the terminal pieces 2a, 2b, 2c, and 2d, Each terminal piece 2a, 2b, 2c, 2d is a battery 1.1
Are arranged on the electrode surfaces 1a and 1b and welded.

Specifically, the inter-battery connection terminal 2
, The terminal pieces 2a, 2b, 2c, 2d have the same shape.

[0016]

According to the method of manufacturing the assembled battery of the present invention and the inter-battery connecting terminal used therefor, each welding electrode rod 6
7 are applied to the separate terminal pieces 2a and 2b, but since the terminal pieces are not in contact with each other due to the existence of the gap 4, the total current D from the welding electrode rod 6 is
It flows to the welding electrode rod 7 through the electrode surfaces 1a and 1b of 1 and the terminal piece in order. Therefore, no reactive current is generated, and the terminal piece and the electrode surfaces 1a and 1b of the battery 1.1 are reliably welded. Moreover, since no reactive current is generated, the current D flowing between the welding electrode rods 6 and 7 can be set to the necessary minimum.

As a result, the power consumption can be suppressed and the inter-battery connecting terminal 2 and the electrode surface 1a
The connection terminals between batteries 2 by suppressing the scattering of molten metal such as 1b
It is possible to reduce damage such as damage to the battery 1 and heat deterioration of the battery 1. As a result, stable welding strength can be obtained and the reliability of the assembled battery can be improved.

Each terminal piece 2a, 2b, of the battery connecting terminal 2
If 2c and 2d have the same shape, the terminal pieces 2a, 2b and 2
It is possible to reduce the time and effort required to manufacture the mold for manufacturing the c and 2d, and also to reduce the time and effort required to manage the parts of the inter-battery connection terminal 2.

[0019]

1 to 8 exemplify an assembled battery according to the present invention and a battery connecting terminal used for the assembled battery. As shown in FIG. 3, the assembled battery is assembled by connecting unit cells 1 such as a cylindrical battery with inter-cell connection terminals 2 and connecting them in series. In the unit cell 1, the metal conductor negative electrode can (electrode surface) 1a, which is the exterior, also serves as a negative electrode terminal, and the metal conductor sealing body (electrode surface) 1b that closes the upper opening of the negative electrode can 1a is a positive electrode terminal. Doubles as Negative electrode can 1a
The sealing body 1b is insulated from the sealing body 1b by the insulating ring 3.

The inter-battery connection terminal 2 is in the form of a stepped cylindrical shape with a downward constriction, and the lower end of the inter-battery connection terminal 2 is series spot welded to the upper surface of the sealing body 1b of the lower unit cell 1. It has become so. Also, the upper diameter side of the upper part of the inter-battery connecting terminal 2 is externally fitted to the lower end of the negative electrode can 1a of the upper unit cell 1 (state of FIG. 3) so that it is series spot welded to the negative electrode can 1a. It has become. The inter-battery connection terminal 2 is divided into four terminal pieces 2a, 2b, 2c, 2d in the circumferential direction as shown in FIGS. 1 and 2, and each terminal piece 2a, 2b, 2c, 2d is connected to the single cell 1. When attached, each terminal piece 2a, 2b, 2c, 2d serves as a sealing body 1b for one unit cell 1 and a negative electrode can 1a for the other unit cell 1.
And the terminal pieces 2a, 2b, 2c
-A gap 4 is formed between 2d. The terminal pieces 2a, 2b, 2c, 2d have the same shape.

Next, a method of manufacturing the assembled battery according to the present invention will be described. First, the four terminal pieces 2 of the inter-battery connection terminal 2
a, 2b, 2c, and 2d are sealing bodies 1b for the lower unit cells 1
On the other hand, they are arranged in concentric circles at equal intervals through the gap 4 (state of FIG. 5). Next, a pair of welding electrode rods 6
As shown in FIG. 4, welding points P1 and P2 are set at the end portions of the adjacent terminal pieces 2a and 2b in the circumferential direction.
Apply each to. At this time, the terminal piece 2a
A gap 4 is present between the welding points P1 and P2 of 2b.

In this state, a current D is passed between the welding electrode rods 6 and 7 as shown in FIG. At this time, each welding electrode rod 6, 7
Is pressed against separate terminal pieces 2a and 2b, and the terminal pieces 2a and 2b are not in contact with each other, the total current D
Flows from the welding electrode rod 6 to the welding electrode rod 7 through the terminal piece 2a, the sealing body 1b and the terminal piece 2b in order, and no reactive current is generated. Due to this current D, the terminal piece 2a and the sealing body 1
b and the sealing body 1b and the terminal piece 2b are welded to each other.

Similarly, the welding electrode rods 6 and 7 are applied to the respective welding points P3 and P4 of the terminal pieces 2b and 2c shown in FIG. 5 to weld between the terminal pieces 2b and 2c and the sealing body 1b, respectively. Also, by applying the welding electrode rods 6 and 7 to the welding points P5 and P6 of the terminal pieces 2c and 2d, respectively.
Weld between d and the sealing body 1b. Further, the welding electrode rods 6 and 7 are connected to the respective welding points P7 of the terminal pieces 2d and 2a.
-Apply to P8 and weld between the terminal pieces 2d and 2a and the sealing body 1b. As a result, the inter-battery connection terminal 2 and the sealing body 1b of the lower unit cell 1 are reliably connected and electrically connected. Note that four sets of welding electrode rods may be simultaneously applied to the welding points P1 to P8 and welded at the same time.

Next, the inter-battery connection terminal 2 and the negative electrode can 1a of the upper unit cell 1 are connected. That is, the upper unit cell 1
As shown in FIG. 7, the negative electrode can 1a of FIG.
It is fitted onto the upper portion of the cylindrical inter-battery connection terminal 2 formed by 2b, 2c and 2d. In this state, the welding electrode rod 6
7 is pressed against the welding points P11 and P12 set at the ends of the upper outer peripheral surfaces of the terminal pieces 2a and 2b, respectively, as shown in FIG. At this time, the terminal pieces 2a and 2b
The gap 4 is located between the welding points P11 and P12.

By passing a current between the welding electrode rods 6 and 7, this current flows from the welding electrode rod 6 to the welding electrode rod 7 through the terminal piece 2a, the negative electrode can 1a and the terminal piece 2b in this order. Due to this current, the terminal piece 2a and the negative electrode can 1a and the terminal piece 2b and the negative electrode can 1a are welded to each other.

Similarly, the welding electrode rods 6 and 7 are applied to the welding points P13 and P14 of the terminal pieces 2b and 2c shown in FIG. 8 to weld between the terminal pieces 2b and 2c and the negative electrode can 1a, respectively. In addition, the welding electrode rods 6 and 7 are connected to the terminal pieces 2c and 2d.
Then, the terminal pieces 2c and 2d and the negative electrode can 1a are welded to the welding points P15 and P16. Further, the welding electrode rods 6 and 7 are applied to the welding points P17 and P18 of the terminal pieces 2d and 2a to weld between the terminal pieces 2d and 2a and the negative electrode can 1a. As a result, the inter-battery connection terminal 2 and the negative electrode can 1a of the upper unit cell 1 are reliably connected, and the upper and lower unit cells 1 are electrically connected in series. The four sets of welding electrode rods may be simultaneously applied to the respective welding points P11 to P18 and welded at the same time.

In this way, adjacent unit cells 1 are connected in series by the inter-battery connection terminals 2 and connected in series. As a result, an assembled battery including a plurality of unit cells 1 is manufactured.

Using the inter-battery connection terminals 2 divided into the terminal pieces 2a of the present invention, 100 battery packs in which six AA nickel-hydrogen storage batteries 1 are connected in series are manufactured, and
Using the inter-battery connection terminals 10 provided with the slits 11 described above, 100 assembled batteries in which six AA nickel-hydrogen storage batteries 1 are connected in series are manufactured.
Compare the resistance values at.

In the assembled battery using the inter-battery connection terminal 10 provided with the slit 11, the resistance value is 17.8 on average.
In contrast to about mΩ, the inter-battery connection terminal 2 of the present invention
In the assembled battery using, the resistance value is 15.8mΩ on average.
It was low. That is, in the assembled battery using the inter-battery connection terminal 2 of the present invention, the welding state between each cell 1 and the inter-battery connection terminal 2 is good and the resistance value is low.

[Brief description of drawings]

FIG. 1 is a top view of an inter-battery connection terminal according to the present invention.

FIG. 2 is a side view of an inter-battery connection terminal.

FIG. 3 is a vertical sectional view of an assembled battery.

4 is a cross-sectional view taken along the line AA of FIG.

FIG. 5 is a top view for explaining the method for manufacturing the assembled battery.

FIG. 6 is a cross-sectional view showing a current flowing during welding.

FIG. 7 is a side view of the assembled battery showing welding points.

FIG. 8 is a cross-sectional view for explaining the method for manufacturing the assembled battery.

FIG. 9 is a vertical cross-sectional view of a conventional assembled battery.

FIG. 10 is a cross-sectional view showing a current flowing during welding at a conventional inter-battery connection terminal.

FIG. 11 is a cross-sectional view showing a current flowing during welding at an inter-battery connecting terminal provided with a slit.

FIG. 12 is a diagram showing a current flowing during welding at an inter-battery connection terminal provided with a slit.

[Explanation of symbols]

1 unit cell 1a negative electrode can 1b Sealing body 2 Battery connection terminal 2a / 2b / 2c / 2d terminal piece 4 gap 6.7 Welding electrode rod

Claims (5)

[Claims] 1. An inter-battery connection terminal by welding one side of the inter-battery connection terminal to the electrode surface of one battery and welding the other side of the inter-battery connection terminal to the electrode surface of the other battery. In the method of manufacturing an assembled battery in which batteries are connected to each other in series, the inter-battery connection terminal is divided into a plurality of terminal pieces, and a gap is present between adjacent terminal pieces, and each terminal piece Each terminal piece is arranged on the electrode surface of the battery so that the electrode surface of the battery and the electrode surface of the other battery are bridged, and the welding of the pair of welding electrode rods is performed on the adjacent terminal pieces with the gap therebetween. A method for manufacturing an assembled battery, wherein each terminal piece is welded to an electrode surface of a battery by applying a current between these welding electrode rods with the electrode rods applied to each other. 2. The method for manufacturing an assembled battery according to claim 1, wherein the terminal pieces of the inter-battery connection terminals have the same shape. 3. The method for manufacturing an assembled battery according to claim 1, wherein an assembled battery composed of at least two batteries is formed by interposing battery connecting terminals between the batteries. 4. A battery wherein one side is welded to the electrode surface of one battery and the other side is welded to the electrode surface of the other battery, thereby connecting adjacent batteries in series. In the inter-connection terminal, it is divided into multiple terminal pieces, with a gap between adjacent terminal pieces, with each terminal piece bridging the electrode surface of one battery and the electrode surface of the other battery. Then, each terminal piece is arranged on the electrode surface of the battery and welded, and the inter-battery connecting terminal is characterized. 5. The inter-battery connection terminal according to claim 4, wherein the terminal pieces have the same shape.