JP6922818B2 - Batteries - Google Patents

Description

The present invention relates to an assembled battery formed by connecting two or more cells. More specifically, it relates to an assembled battery configured so that the assembled battery can be disassembled and reassembled.

As an example of the conventional assembled battery, the one described in Patent Document 1 can be mentioned. Generally, in assembled batteries including those in the same document, terminals are connected to each other between cells by using a conductive member called a bus bar. In the assembled battery of the same document, the terminal of the cell and the bus bar are connected by fastening bolts and nuts (for example, "81", "31", "39" in FIG. 10 in the same document). The invention of the same document aims at facilitating temporary fixing when assembling a bolt to a battery (the third sentence of [0003] in the same document).

International Publication No. 2008/084883

However, the above-mentioned conventional technique has the following problems. Since bolts and nuts are used to connect the busbar, the number of parts is large and it is difficult to make the connection structure part compact. The size depends on the battery capacity, but for example, in the case of mounting on a vehicle, a protruding height of about 15 mm from the surface of the cell to the top of the bolt may be required. If welding is used instead of bolt-nut fastening, the size of the connection structure can be reduced, but on the contrary, there is a problem that it becomes extremely difficult to disassemble and reassemble the assembly.

The present invention has been made to solve the problems of the above-mentioned conventional techniques. That is, the problem is to provide an assembled battery in which the connection portion between cells is compact and the assembled battery can be disassembled and reassembled.

The assembled battery according to one aspect of the present invention is an assembled battery having at least a first cell and a second cell and having a terminal connection portion between the first cell and the second cell, and the first cell contains a terminal connection portion. In addition to being connected to the power generation element inside the cell, it has a first terminal member arranged so as to straddle the surface on the side of the terminal connection point and the adjacent surface outside the cell, and power is generated in the second cell in the cell. It has a second terminal member that is connected to the element and is arranged outside the cell so as to straddle the surface on the side of the terminal connection portion and the adjacent surface thereof, and the first terminal member and the second terminal member are located at the terminal connection portion. At the point of contact between the first terminal member and the second terminal member, at least one of the first terminal member and the second terminal member is a protruding section protruding toward the other. , Between the first elastic member sandwiched between the terminal connection point side surface in the first cell and the first terminal member, and the terminal connection point side surface in the second cell and the second terminal member. The sandwiched second elastic member, the compression member that presses the first cell and the second cell in a direction close to each other, and the portion between the first cell and the second cell other than the terminal connection portion are filled. It has a spacer, and the contact point between the first terminal member and the second terminal member is within the maximum range in which the spacer exists and is within the maximum range when viewed from the direction intersecting the arrangement direction of the first cell and the second cell. Ri range near the first resilient member and second resilient members are present, the total thickness of at the terminal connection portions of the first terminal member and the second terminal member and T1, the first resilient member and second resilient members The total thickness at the terminal connection points is T2, the spacer thickness is T3, the spring constant for bending deformation of the first terminal member and the second terminal member is K1, and the first elastic member and the second elastic member. When the spring constant for compression of is K2 and the spring constant for compression of the spacer is K3, {(K1 × T1) + (K2 × T2)} is within ± 10% of (K3 × T3). It is a thing.

In the assembled battery in the above embodiment, the connection between the terminals between the first cell and the second cell is due to the contact between the first terminal member and the second terminal member on the surface where the first cell and the second cell face each other. It is done. Therefore, the set can be easily disassembled and reconstructed by releasing the restraint. And since it is not necessary to fasten bolts and nuts, the outer shape of the terminal connection point is compact.

According to this configuration, an assembled battery is provided in which the connection portion between cells is compact and the assembled battery can be disassembled and reassembled.

It is sectional drawing which shows the whole structure of the assembled battery which concerns on embodiment. It is a perspective view which shows typically the connection state of the cell in the assembled battery of FIG. It is sectional drawing which shows the part of FIG. 1 enlarged. It is sectional drawing which shows a part of FIG. 3 further enlarged. It is sectional drawing which shows the whole structure of the assembled battery which concerns on the modified form (parallel). It is a perspective view which shows typically the connection state of the cell in the assembled battery of FIG. It is sectional drawing which shows the part of FIG. 5 enlarged.

Hereinafter, embodiments embodying the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, the present invention is applied to the assembled battery 1 shown in FIG. The assembled battery 1 of FIG. 1 has eight cells 2 connected in series. Each cell 2 is a flat-angle type battery, and positive and negative terminals are provided near both ends of the upper portion. Restraint plates 3 are arranged on both outer sides of the eight cells 2. Further, a restraint spacer 4 which is an elastic material is arranged between the cells 2 and between the cell 2 and the restraint plate 3. Further, a restraint band 5 is provided on the outside of the entire assembled battery 1. Due to the elasticity of the restraint band 5, the entire assembled battery 1 is pressed in the left-right direction in FIG. That is, each cell 2 of the assembled battery 1 is pressed in the thickness direction thereof.

As shown in FIG. 2, each cell 2 in the assembled battery 1 is arranged so that the directions of the positive and negative terminals of the adjacent cells 2 are opposite to each other. Then, between the adjacent cells 2, the terminals on the right side and the terminals on the left side are alternately connected to each other. As a result, a series connection is formed in the entire assembled battery 1. In FIG. 2, the cells 2 are drawn with a considerable space between them, but they are actually arranged more closely. FIG. 1 is a cross-sectional view taken along the right side terminal of each cell 2 in FIG.

A part of FIG. 1 is enlarged and shown in FIG. FIG. 3 shows the vicinity of the upper part of two adjacent cells 2 in FIG. The two cells 2 in FIG. 3 are the odd-numbered cell 2 from the left and the cell 2 to the right of the odd-numbered cell 2 in FIG. Hereinafter, the cell 2 on the left side in FIG. 3 is referred to as a first cell 21, and the cell 2 on the right side is referred to as a second cell 22. Both the first cell 21 and the second cell 22 are formed by enclosing the power generation element 7 in the box body 6. The box body 6 has a flat square shape as can be seen from the overall shape of the cell 2 seen in FIG. The power generation element 7 is a stack of a positive electrode plate and a negative electrode plate.

A current collecting terminal 8 is provided inside each of the first cell 21 and the second cell 22. The current collecting terminal 8 is connected to the power generation element 7. However, the current collecting terminal 8 of the first cell 21 is connected to the positive electrode plate of the power generation element 7, and the current collecting terminal 8 of the second cell 22 is connected to the negative electrode plate of the power generation element 7.

The portion between the first cell 21 and the second cell 22 is the terminal connection portion 9. At the terminal connection portion 9, the positive electrode terminal member 10 of the first cell 21 and the negative electrode terminal member 11 of the second cell 22 are connected. The positive electrode terminal member 10 is connected to the positive electrode plate of the power generation element 7 via the current collecting terminal 8 in the first cell 21. The negative electrode terminal member 11 is connected to the negative electrode plate of the power generation element 7 via the current collecting terminal 8 in the second cell 22.

The positive electrode terminal member 10 is arranged outside the cell of the first cell 21 so as to straddle the surface on the side of the terminal connection portion 9 (the surface on the right side in FIG. 3) and the upper surface next to the surface. The negative electrode terminal member 11 is arranged outside the cell of the second cell 22 so as to straddle the surface on the side of the terminal connection portion 9 (the surface on the left side in FIG. 3) and the upper surface next to the surface. A contact portion 12 between the positive electrode terminal member 10 and the negative electrode terminal member 11 is provided between the first cell 21 and the second cell 22 (terminal connection portion 9). At the contact point 12, both the positive electrode terminal member 10 and the negative electrode terminal member 11 have a protruding section having a shape protruding toward the other side. At the contact point 12, the positive electrode terminal member 10 and the negative electrode terminal member 11 are only in contact with each other, and are not joined by welding or other methods. Hereinafter, the range in which the positive electrode terminal member 10 and the negative electrode terminal member 11 are in contact with each other at the contact point 12 is referred to as a contact range C.

The first elastic member 13 is sandwiched between the contact portion 12 between the positive electrode terminal member 10 and the negative electrode terminal member 11 and the box body 6 of the first cell 21. Like the positive electrode terminal member 10, the first elastic member 13 is arranged so as to straddle the upper surface from the surface on the side of the terminal connection portion 9 outside the cell of the first cell 21. The first elastic member 13 is also for insulating the positive electrode terminal member 10 and the box body 6 of the first cell 21. Similarly, the second elastic member 14 is sandwiched between the contact portion 12 and the box body 6 of the second cell 22. The second elastic member 14 is the same as the first elastic member 13 in the first cell 21.

The portion of the positive electrode terminal member 10 and the negative electrode terminal member 11 near the contact portion 12 and the box body 6 of the first cell 21 and the second cell 22 are filled with the first elastic member 13 or the second elastic member 14. Has been done. In this portion, it can be said that the space between the first cell 21 and the second cell 22 is filled with the positive electrode terminal member 10, the negative electrode terminal member 11, the first elastic member 13, and the second elastic member 14. The space between the first cell 21 and the second cell 22 is filled with the restraint spacer 4 in a range other than the range in which the first elastic member 13 and the second elastic member 14 exist. As can be seen from FIG. 2, the restraint spacer 4 is a flat plate member having a substantially rectangular shape as a whole, but has a shape in which the terminal connection portion 9 is cut out.

Hereinafter, in FIG. 3, that is, the range in which the first elastic member 13 and the second elastic member 14 exist between the first cell 21 and the second cell 22 when viewed from the direction intersecting the cell arrangement direction. Is referred to as a terminal pressurizing range D. Further, the maximum range in which the restraint spacer 4 exists between the first cell 21 and the second cell 22 is referred to as a restraint range E. Regarding the restraint range E, it is necessary to consider the part where the terminal connection part 9 is not provided. Therefore, the restraint range E is wide (see FIG. 1), and in FIG. 3, it seems that the terminal pressurization range D is also substantially included in the restraint range E. The above-mentioned contact range C is a range included in both the terminal pressurization range D and the restraint range E. Note that the voltage detection probe 15 arranged at the terminal connection portion 9 is also drawn in FIG.

In FIG. 3, a restraint load F in the left-right direction is applied to each cell and other members. Therefore, the restraint spacer 4, the first elastic member 13, and the second elastic member 14 are also in a state of being slightly compressed in the horizontal direction H in FIG. Bending stress is also applied to the positive electrode terminal member 10 and the negative electrode terminal member 11. The restraint load F is, of course, due to the elasticity of the restraint band 5 in FIG. As a result, at the terminal connection portion 9, the positive electrode terminal member 10 and the negative electrode terminal member 11 are pressed against each other and are in reliable contact with each other.

Here, the relationship between the thickness and elasticity of the restraint spacer 4, the first elastic member 13, the second elastic member 14, the positive electrode terminal member 10, and the negative electrode terminal member 11 will be described. First, the related parameters are defined as follows.
T1: Total thickness of the positive electrode terminal member 10 and the negative electrode terminal member 11 at the contact point 12 T2: Total thickness of the first elastic member 13 and the second elastic member 14 at the contact point 12 T3: Restraint spacer Thickness of 4 K1: Spring constant for bending deformation of positive electrode terminal member 10 and negative electrode terminal member K2: Spring constant for compression of first elastic member 13 and second elastic member 14 K3: Spring constant for compression of restraint spacer 4

The above T2 and T3 are in a state where the assembled battery 1 is completed, that is, in a state where a restraining load F is applied. Therefore, T3 = T1 + T2.

Here, the materials of the positive electrode terminal member 10 and the negative electrode terminal member 11, and the materials of the first elastic member 13 and the second elastic member 14 are all the same. If the materials are different, each individual thickness is needed, not the total thickness. Spring constants are also required for each.

In the assembled battery 1 of this embodiment, it is desirable that the following relationship is established between each of the above parameters. If the difference is within ± 10%, it may be considered to be almost equal.
(K1 x T1) + (K2 x T2) ≒ (K3 x T3)

The meaning of this equation is that there is a terminal connection point 9 between cells (terminal pressurization range D) and a place where the restraint spacer 4 fills the space between cells without being a terminal connection point 9. It means that the compressive stress is equal with (the range of the restraint range E that is not the terminal pressurization range D). As a result, due to the relationship between the contact range C, the terminal pressurization range D, and the restraint range E described above, the compressive stress is evenly applied to the entire first cell 21 and the second cell 22, and the restraint surface pressure is properly secured. The Rukoto. Further, since the restraint surface pressure is uniformly applied to the contact portion 12, the contact resistance is low. Further, it is possible to prevent the positive electrode terminal member 10 and the negative electrode terminal member 11 from being deformed. If the materials of the positive electrode terminal member 10 and the negative electrode terminal member 11 are different, or if the materials of the first elastic member 13 and the second elastic member 14 are different, the first term or the second item on the left side of the above equation. The term shall be the sum of the products of the thickness of each member and the spring constant.

The assembled battery 1 configured as described above has the following advantages. First, as described above, the contact resistance of the terminal connection portion 9 is low. That is, the quality of the connection itself is high. Second, the terminal connection point 9 is compact. As shown in FIG. 4, the apparent size of the terminal connection portion 9 of the assembled battery 1 is about the protrusion height P from the upper surface of the box body 6 of the first elastic member 13 (the same applies to the second elastic member 14). There is only. Since the protruding height P can be easily stopped to about 3 to 5 mm, it is sufficiently compact as compared with the case of bolt-nut fastening. Third, the set can be easily disassembled by removing the restraint band 5. Of course, each of the disassembled cells 2 can be reassembled with the assembled battery 1.

In the above-mentioned assembled battery 1, the portion of the negative electrode terminal in the first cell 21 has a structure in which the structure shown as the second cell 22 in FIG. 3 is reversed left and right. Similarly, the portion of the positive electrode terminal in the second cell 22 is a left-right inverted structure of the structure shown as the first cell 21 in FIG. That is, in the assembled battery 1, the first cell 21 and the second cell 22 are not the same, and the forming surfaces of the terminal connection points 9 are opposite to each other.

The present invention is applicable not only to the series-connected assembled battery 1 as described above, but also to parallel-connected batteries. FIGS. 5, 6 and 7 show a diagram in the case of parallel connection, which corresponds to FIGS. 1, 2 and 3 in the case of the above-mentioned series connection. In the parallel-connected assembled battery 16 shown in FIG. 5, all the cells 23 are arranged with the positive electrodes facing the front side. The positive electrodes of all the cells 23 are connected to each other by the terminal connection points 17 next to each other. The same applies to the negative electrode side as shown in FIG. In the cell 23 terminal portion of the assembled battery 16, the positive electrode terminal members 18 are arranged toward both sides as shown in FIG. Although not shown, the negative electrode terminal side has the same structure. In the assembled battery 16 shown in FIG. 5, there are three types of cells 23: the one on the leftmost side, the one on the rightmost side, and the other six. However, the assembled battery 16 can be configured with only one type corresponding to the above "other six".

As described in detail above, according to the present embodiment, the terminal members outside the cells in each cell are arranged so as to straddle the surface on which the cells face each other and the surface on the adjacent surface thereof. Then, the terminal members are brought into contact with each other on the surface where the cells face each other. Then, the whole is restrained by the restraint band 5, the restraint spacer 4, and the like. As a result, the assembled batteries 1 and 16 have been realized in which the connection portion between the cells is compact and the set can be disassembled and reassembled.

It should be noted that the present embodiment is merely an example and does not limit the present invention in any way. Therefore, as a matter of course, the present invention can be improved and modified in various ways without departing from the gist thereof. For example, at the terminal connection points 9 and 17 in the above-described embodiment, both terminal members have a shape protruding toward each other. However, the present invention is not limited to this, and only one terminal member may have a protruding shape and the other terminal member may be flat. Further, only one terminal member may have a protruding shape and the other terminal member may have a slightly recessed shape.

1,16 battery 2 cell 3 restraint plate 4 restraint spacer 5 restraint band (compression member)
6 Box 7 Power generation element 8 Current collecting terminals 9, 17 Terminal connection points 10 Positive terminal member 11 Negative terminal member 12 Contact point 13 1st elastic member 14 2nd elastic member 18 Positive terminal member 21 1st cell 22 2nd cell 23 Cell C Contact range D Terminal pressurization range E Restraint range

Claims (1)

An assembled battery having at least a first cell and a second cell, and having a terminal connection point between the first cell and the second cell.
The first cell has a first terminal member that is connected to a power generation element inside the cell and is arranged outside the cell so as to straddle a surface on the side of the terminal connection portion and an adjacent surface thereof.
The second cell has a second terminal member that is connected to a power generation element inside the cell and is arranged outside the cell so as to straddle a surface on the side of the terminal connection portion and an adjacent surface thereof.
The first terminal member and the second terminal member are in contact with each other at the terminal connection portion, and at the contact portion between the first terminal member and the second terminal member, the first terminal member and the first terminal member are in contact with each other. At least one of the two terminal members is a protruding section protruding toward the other.
A first elastic member sandwiched between a surface on the side of the terminal connection portion in the first cell and the first terminal member,
A second elastic member sandwiched between the surface of the second cell on the side of the terminal connection portion and the second terminal member,
A compression member that compresses the first cell and the second cell in a direction in which they are close to each other,
It has a spacer between the first cell and the second cell that fills a portion other than the terminal connection portion.
When the contact point between the first terminal member and the second terminal member intersects the arrangement direction of the first cell and the second cell, it is within the maximum range in which the spacer exists, and the said. Ri range near the first resilient member and the second resilient member is present,
The total thickness of the first terminal member and the second terminal member at the terminal connection portion is T1, and the total thickness of the first elastic member and the second elastic member at the terminal connection portion is T2. The thickness of the spacer is T3, the spring constant for bending deformation of the first terminal member and the second terminal member is K1, and the spring constant for compression of the first elastic member and the second elastic member is K2. When the spring constant for compression of the spacer is K3,
Is {(K1 × T1) + ( K2 × T2)}, the battery pack characterized by range near Rukoto of ± 10% of (K3 × T3).

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