JP2007141768A - Battery pack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery pack having high space efficiency and capable of conducting charge/discharge in one control system. <P>SOLUTION: The battery pack 100 is equipped with a plurality of first cylindrical secondary batteries 110 and a plurality of second cylindrical secondary batteries 120 having smaller diameter than the first secondary batteries 110. The first secondary batteries 110 and the second secondary batteries 120 are arranged so that these shaft lines become in parallel, so that the second secondary batteries 120 are positioned in gaps between the first secondary batteries 110 adjacent in the diameter direction. The second secondary batteries 120 are made longer than the first secondary batteries 110 in the shaft line direction and have the same capacity as the first secondary batteries 110. Either of the plurality of first secondary batteries 110 and the plurality of second secondary batteries 120 are electrically connected in series. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the present invention, a plurality of secondary batteries having a plurality of secondary batteries, in particular, two types of secondary batteries having different outer diameters are arranged side by side in the radial direction (direction perpendicular to the axial direction). It is related with the assembled battery.

In recent years, there has been proposed an assembled battery in which a plurality of two types of secondary batteries having different outer diameters are arranged side by side in the radial direction (a direction orthogonal to the axial direction) (see, for example, Patent Document 1). ).
JP 2004-355861 A

  In Patent Document 1, a plurality of secondary batteries having a columnar shape are a first battery group that is arranged in a container with a predetermined interval, and a plurality of secondary batteries having a columnar shape, A battery module comprising a second battery group in which a secondary battery having a smaller diameter than the secondary batteries constituting the first battery group is disposed in a gap between the secondary batteries constituting the first battery group Battery) has been proposed. Thus, by arranging the secondary batteries having a small diameter in the gaps inevitably formed when the secondary batteries constituting the first battery group are arranged, the unit without changing the size of the battery module. It is described that the energy density per volume can be improved.

  By the way, in patent document 1, it is based on two control systems, the 1st electric control system which controls charging / discharging of a 1st battery group, and the 2nd electric control system which controls charging / discharging of a 2nd battery group. The charging / discharging of the assembled battery is controlled. However, in order to simplify the charge / discharge control, it may be required to control the charge / discharge of the entire assembled battery with a single control system.

  However, in Patent Document 1, the secondary battery constituting the second battery group (referred to as the second secondary battery) is compared with the secondary battery constituting the first battery group (referred to as the first secondary battery). ) Has a small diameter, the battery capacity of the second secondary battery is smaller than that of the first secondary battery. For this reason, in order to connect the first secondary battery and the second secondary battery in series and control charging / discharging safely with one control system, charging / discharging is performed on the second secondary battery having a small battery capacity. Since the amount of charge must be matched, there is a problem that energy efficiency is greatly reduced. Note that adjusting the input / output charge amount to the first secondary battery having a large battery capacity is extremely dangerous because the overcharge / overdischarge is repeated in the second secondary battery having a small battery capacity.

  This invention is made | formed in view of this present condition, Comprising: It aims at providing the assembled battery which can perform charging / discharging with one control system | strain with favorable space efficiency.

  The solution includes a plurality of first secondary batteries having a columnar shape and a plurality of second secondary batteries having a columnar shape having a smaller diameter than the first secondary battery, and the first secondary battery. The first secondary battery and the second secondary battery have their axes aligned so that the second secondary battery is positioned in the gap between the first secondary batteries adjacent to each other in the radial direction of An assembled battery arranged parallel to each other, wherein the second secondary battery is longer in the axial direction than the first secondary battery, and has the same battery capacity as the first secondary battery, The assembled battery includes a plurality of the first secondary batteries arranged side by side in the axial direction rather than the number of the second secondary batteries arranged in the axial direction. Each of the battery and the plurality of second secondary batteries is an assembled battery that is electrically connected in series.

  In the assembled battery of the present invention, the second secondary battery having a smaller diameter than the first secondary battery is positioned in the gap between the first secondary batteries adjacent to each other in the radial direction of the first secondary battery. The first secondary battery and the second secondary battery are arranged with their axes parallel to each other. Thus, space efficiency is improved by arranging two types of secondary batteries having different outer diameters in combination.

  Moreover, in the assembled battery of the present invention, the second secondary battery having a small diameter is longer in the axial direction than the first secondary battery. Thereby, the battery capacity of the 1st secondary battery and the 2nd secondary battery is made equal. For this reason, a 1st secondary battery and a 2nd secondary battery can be electrically connected in series safely, and it becomes possible to charge / discharge with one control system.

  By the way, when two types of secondary batteries having different axial lengths are arranged one by one in the axial direction, a space is vacated in the axial direction of the first secondary battery having a short axial length. Efficiency will decrease. On the other hand, in the assembled battery of the present invention, more first secondary batteries are arranged side by side in the axial direction than the number of second secondary batteries arranged in the axial direction. As described above, the space efficiency can be improved by adjusting the number of the first secondary battery and the second secondary battery arranged in the axial direction.

For example, when the axial length of the second secondary battery is twice the axial length of the first secondary battery, one second secondary battery is arranged in the axial direction. Two first secondary batteries are preferably arranged side by side in the axial direction. By arranging in this way, space is not wasted not only in the radial direction of the secondary battery but also in the axial direction, so that an assembled battery with good space efficiency is obtained.
Therefore, the assembled battery of the present invention is an assembled battery that has good space efficiency and can be charged and discharged by one control system.

The number of the second secondary batteries arranged in the axial direction may be one or plural.
In addition, as the first secondary battery and the second secondary battery, any secondary battery such as a lithium ion secondary battery or a nickel metal hydride secondary battery may be used as long as it is a cylindrical secondary battery. it can.

  Further, in the above assembled battery, the length of the first battery row in which the plurality of first secondary batteries are arranged in the axial direction and the one or more second secondary batteries are arranged in the axial direction. An assembled battery in which the length of the second battery row is made equal is preferable.

  In the assembled battery of the present invention, the length of the first battery row is equal to the length of the second battery row. As a result, space is not wasted in the axial direction, and the space efficiency is further improved.

  Another solving means is a battery system comprising any one of the above assembled batteries and a control means for controlling charge / discharge of the assembled battery.

  This battery system includes any one of the above assembled batteries. For this reason, the space efficiency of an assembled battery is favorable, and charging / discharging of an assembled battery can be performed by one control means (control system).

Next, Embodiments 1 and 2 of the present invention will be described with reference to the drawings.
Example 1
FIG. 1 is an explanatory diagram showing the arrangement of the secondary batteries (the first secondary battery 110 and the second secondary battery 120) in the assembled battery 100 according to the first embodiment. As shown in FIG. 1, the assembled battery 100 according to the first embodiment includes a plurality of first secondary batteries 110 and a plurality of second secondary batteries 120. The assembled battery 100 is housed inside the housing case 10.

  As shown in FIG. 2, the first secondary battery 110 has a cylindrical shape (outer diameter D1). The first secondary battery 110 includes a cylindrical battery case 111, a positive terminal 112 located on one end side (left end side in FIG. 2) of the battery case 111, and the other end side (right end side in FIG. 2). And a negative electrode terminal 113 which is positioned. Although not shown, the battery case 111 contains a wound body formed by winding a belt-like positive electrode, a negative electrode, and a separator, and an electrolytic solution.

  As shown in FIG. 3, the second secondary battery 120 has a cylindrical shape (outer diameter dimension D <b> 2) having a smaller diameter than the first secondary battery 110. The second secondary battery 120 includes a cylindrical battery case 121, a negative electrode terminal 123 located on one end side (left end side in FIG. 3) of the battery case 121, and the other end side (right end side in FIG. 3). And a positive electrode terminal 122 positioned therein. Although not shown, the battery case 121 contains a wound body formed by winding a belt-like positive electrode, a negative electrode, and a separator.

  In the first embodiment, the battery capacity of the second secondary battery 120 is equal to the battery capacity of the first secondary battery 110 (specifically, 3 to 15 Ah). Further, a length L2 (hereinafter, also simply referred to as an axial direction length L2) in the direction along the axis C2 of the second secondary battery 120 (hereinafter also referred to simply as the axial direction length L2) is along the axis C1 of the first secondary battery 110. The length L1 in the direction (left-right direction in FIG. 2) (hereinafter also simply referred to as the axial direction length L1) is twice as long.

In the first embodiment, the assembled battery 100 is configured by combining the first secondary battery 110 and the second secondary battery 120 as described below.
Specifically, as shown in FIG. 1, a plurality of first secondary batteries 110 are arranged in a radial direction (a direction along the paper surface in FIG. 1) with the axis C <b> 1 being parallel to each other inside the housing case 10. They are arranged in a grid with gaps. Further, the plurality of second secondary batteries 120 are tilted by 45 degrees with respect to the radial direction (specifically, in FIG. 1, with respect to the horizontal direction, with their axis C2 parallel to the axis C1 of the first secondary battery 110). In the direction) between the first secondary batteries 110 adjacent to each other.

As described above, in the first embodiment, the first secondary battery 110 (outer diameter dimension D1) has a smaller diameter (outer diameter dimension D2) than the first secondary battery 110 in the gap that is inevitably generated when the first secondary batteries 110 (outer diameter dimension D1) are arranged. A second secondary battery 120 is arranged. For this reason, the assembled battery 100 of the first embodiment is more space efficient than the assembled battery in which only the first secondary batteries 110 are arranged as described above. In other words, the energy density per unit volume of the assembled battery can be improved by adding the second secondary battery 120.
In Example 1, in order to improve the cooling performance of the first secondary battery 110 and the second secondary battery 120, the first secondary battery 110 and the second secondary battery 120 are arranged in the radial direction. Arranged with a gap.

  Furthermore, in the assembled battery 100 of the first embodiment, the first secondary battery 110 and the second secondary battery 120 are electrically connected in series. Specifically, as shown in FIG. 4, two first secondary batteries 110 are arranged in the axial direction (left-right direction in FIG. 4), and one first secondary battery 110 (the first secondary battery 110 located on the right side in FIG. 4) is arranged. The first battery array 101 is connected to the positive terminal 112 of the first secondary battery 110) and the negative terminal 113 of the other first secondary battery 110 (the first secondary battery 110 located on the left side in FIG. 4). Is forming. Further, as shown in FIG. 5, the plurality of first battery rows 101 formed in this way and the plurality of second secondary batteries 120 (in the first embodiment, one second secondary battery 120 is used as the second battery. Are formed through a conductive member 60. In this way, all the first secondary batteries 110 and the second secondary batteries 120 constituting the assembled battery 100 are electrically connected in series.

  By the way, in Example 1, as described above, the battery capacity of the first secondary battery 110 and the battery capacity of the second secondary battery 120 are made equal. Therefore, the first secondary battery 110 and the second secondary battery 120 can be safely and electrically connected in series, and the assembled battery 100 is charged and discharged by one control system. (See FIG. 5).

  Furthermore, in the assembled battery 100 of the first embodiment, the axial length L2 of the second secondary battery 120 is twice the axial length L1 of the first secondary battery 110 as described above. Therefore, as shown in FIG. 4, the axial length of the first battery row 101 (battery row in which two first secondary batteries 110 are connected in series) and the second battery row 102 (second secondary battery 120). Are equal to each other in the axial direction length. As a result, no space is wasted in the axial direction, and the space efficiency is extremely good.

Next, the battery system 200 of the first embodiment will be described.
As illustrated in FIG. 5, the battery system 200 according to the first embodiment includes the above-described assembled battery 100 and a control unit 210 (control unit) that controls charging / discharging of the assembled battery 100. Further, the control unit 210 is connected to the motor 30. Thereby, the electric power feeding (discharge) from the assembled battery 100 to the motor 30 (load) and the charging to the assembled battery 100 from the motor 30 (generator) can be performed appropriately.

In particular, in the battery system 200 of the first embodiment, the first secondary battery 110 and the second secondary battery 120 constituting the assembled battery 100 are both connected in series. Thereby, charging / discharging of the assembled battery 100 whole can be controlled by one control part 210 (control means).
For this reason, for example, a battery system including two control systems (control units) in which only the first secondary battery is connected in series and only the second secondary battery is connected in series in a separate system (for example, Compared with the case of the battery system disclosed in Patent Document 1, the charge / discharge control can be simplified and the output characteristics are also improved. Moreover, since the 1st secondary battery 110 and the 2nd secondary battery 120 can be used simultaneously, the utilization efficiency of each secondary battery (the 1st secondary battery 110 and the 2nd secondary battery 120) also becomes high.

(Example 2)
Compared to the assembled battery 100 of the first embodiment, the assembled battery 300 of the second embodiment has dimensions and battery capacities of the first secondary battery and the second secondary battery, and the first secondary battery forming the first battery array. The number is different, and the others are almost the same.
FIG. 6 is an explanatory diagram showing the arrangement of the secondary batteries (the first secondary battery 310 and the second secondary battery 320) of the assembled battery 300 according to the second embodiment. As shown in FIG. 6, the assembled battery 300 according to the second embodiment includes a plurality of first secondary batteries 310 and a plurality of second secondary batteries 320. The assembled battery 300 is housed inside the housing case 20.

  As shown in FIG. 7, the first secondary battery 310 has a cylindrical shape (outer diameter D3). The first secondary battery 310 includes a cylindrical battery case 311, a positive electrode terminal 312 located on one end side (left end side in FIG. 7) of the battery case 311, and the other end side (right end side in FIG. 7). And a negative electrode terminal 313 which is positioned. Although not shown, the battery case 311 contains a wound body obtained by winding a belt-like positive electrode, a negative electrode, and a separator, and an electrolytic solution.

  As shown in FIG. 8, the second secondary battery 320 has a cylindrical shape (outer diameter dimension D <b> 4) having a smaller diameter than the first secondary battery 310. The second secondary battery 320 includes a cylindrical battery case 321, a negative terminal 323 located on one end side (left end side in FIG. 8) of the battery case 321 and the other end side (right end side in FIG. 8). And a positive electrode terminal 322 positioned therein. Although not shown, the battery case 321 contains a wound body formed by winding a belt-like positive electrode, a negative electrode, and a separator.

  In the second embodiment, the battery capacity of the second secondary battery 320 is equal to the battery capacity of the first secondary battery 310 (specifically, 3 to 15 Ah). Further, the length L4 in the direction along the axis C4 of the second secondary battery 320 (left and right direction in FIG. 8) (hereinafter also simply referred to as the axial direction length L4) is along the axis C3 of the first secondary battery 310. The length L3 in the direction (left-right direction in FIG. 7) (hereinafter, also simply referred to as the axial direction length L3) is six times.

In the first embodiment, the assembled battery 300 is configured by combining the first secondary battery 310 and the second secondary battery 320 as described below.
Specifically, as shown in FIG. 6, the plurality of first secondary batteries 310 are arranged in the radial direction (in the direction along the paper surface in FIG. 6) with the axis C <b> 3 being parallel to each other inside the housing case 20. The first secondary batteries 310 adjacent to each other are arranged in a grid pattern. Further, the plurality of second secondary batteries 120 are tilted by 45 degrees with respect to the radial direction (specifically, in FIG. 6, with respect to the horizontal direction, with their axis C4 parallel to the axis C3 of the first secondary battery 310). In the direction) between the first secondary batteries 310 adjacent to each other.

  As described above, in the first embodiment, the plurality of first secondary batteries 310 (outer diameter D3) are arranged in contact with each other, and the gap inevitably generated at this time is larger than that of the first secondary battery 310. A second secondary battery 320 having a small diameter (outer diameter dimension D4) is arranged. For this reason, the assembled battery 300 of the first embodiment is more space efficient than the assembled battery 100 of the first embodiment, and the energy density per unit volume of the assembled battery is improved.

  Further, in the assembled battery 300 of the second embodiment, as in the first embodiment, the first secondary battery 310 and the second secondary battery 320 are electrically connected in series. Specifically, as shown in FIG. 9, six first secondary batteries 110 are arranged in the axial direction (left-right direction in FIG. 9), and the positive terminal 112 and the negative electrode of the first secondary battery 310 adjacent in the axial direction. The terminal 113 is connected to form a first battery row 301. Further, as shown in FIG. 10, the plurality of first battery rows 301 formed in this way and the plurality of second secondary batteries 320 (in the second embodiment, one second secondary battery 120 is used as the second battery). Column 302 is formed) via a conductive member 70. In this way, all the first secondary batteries 310 and the second secondary batteries 320 constituting the assembled battery 300 are electrically connected in series.

  By the way, also in this Example 2, the battery capacity of the 1st secondary battery 310 and the battery capacity of the 2nd secondary battery 320 are made equal similarly to Example 1. FIG. For this reason, like the first embodiment, the first secondary battery 310 and the second secondary battery 320 can be safely and electrically connected in series, and in addition, the assembled battery can be connected by one control system. It is possible to charge and discharge 300 (see FIG. 10).

  Furthermore, in the assembled battery 300 of the second embodiment, as described above, the axial length L4 of the second secondary battery 320 is six times the axial length L3 of the first secondary battery 310. Therefore, as shown in FIG. 9, the axial length of the first battery row 301 (battery row in which six first secondary batteries 310 are connected in series) and the second battery row 302 (second secondary battery 320). Are equal to each other in the axial direction length. As a result, no space is wasted in the axial direction, and the space efficiency is extremely good.

Next, the battery system 400 according to the second embodiment will be described.
As illustrated in FIG. 10, the battery system 400 according to the second embodiment includes the above-described assembled battery 300 and a control unit 410 (control unit) that controls charging / discharging of the assembled battery 300. Further, the control unit 410 is connected to the motor 50. As a result, power supply (discharge) from the assembled battery 300 to the motor 50 (load) and charging of the assembled battery 300 from the motor 50 (generator) can be performed appropriately.

In particular, in the battery system 200 of the second embodiment, as in the first embodiment, the first secondary battery 310 and the second secondary battery 320 constituting the assembled battery 300 are both connected in series. Thereby, charging / discharging of the assembled battery 300 whole can be controlled by one control part 410 (control means).
For this reason, for example, a battery system including two control systems (control units) in which only the first secondary battery is connected in series and only the second secondary battery is connected in series in a separate system (for example, Compared with the case of the battery system disclosed in Patent Document 1, the charge / discharge control can be simplified and the output characteristics are also improved.

  In the above, the present invention has been described with reference to the first and second embodiments. However, the present invention is not limited to the above-described embodiments and the like, and it can be applied as appropriate without departing from the scope of the present invention. Not too long.

  For example, in the assembled batteries 100 and 300 of the first and second embodiments, the second battery rows 102 and 302 are formed by one second secondary battery 120 and 320, but a plurality of like the first battery rows 101 and 301. The second secondary batteries may be arranged in the axial direction to form a second battery row. For example, the second battery array may be formed by arranging two second secondary batteries in the axial direction, and the first battery array may be formed by arranging three first secondary batteries in the axial direction. However, in order to appropriately control charging / discharging of the assembled battery with one control system (control means), it is necessary to make the battery capacities of the first secondary battery and the second secondary battery equal. Further, there is no wasted space in the axial direction, and in order to improve space efficiency, the length of the first battery row and the length of the second battery row are made equal to each other in the first secondary battery and the second secondary battery. It is preferred to select the length.

3 is an explanatory diagram showing an arrangement of secondary batteries (first secondary battery 110 and second secondary battery 120) of the assembled battery 100 according to Example 1. FIG. 1 is a side view of a first secondary battery 110 according to Example 1. FIG. 3 is a side view of a second secondary battery 120 according to Example 1. FIG. 1 is a side view of an assembled battery 100 according to Example 1. FIG. It is a figure which shows the structure of the battery system 200 concerning Example 1. FIG. FIG. 6 is an explanatory diagram showing an arrangement of secondary batteries (first secondary battery 310 and second secondary battery 320) of the assembled battery 300 according to Example 2; 3 is a side view of a first secondary battery 310 according to Example 2. FIG. 6 is a side view of a second secondary battery 320 according to Example 2. FIG. 6 is a side view of an assembled battery 300 according to Example 2. FIG. 6 is a diagram showing a configuration of a battery system 400 according to Example 2. FIG.

Explanation of symbols

100, 300 Battery pack 101, 301 First battery row 102, 302 Second battery row 110, 310 First secondary battery 120, 320 Second secondary battery 200, 400 Battery system

Claims (2)

A plurality of first secondary batteries having a cylindrical shape;
A plurality of second secondary batteries having a cylindrical shape smaller in diameter than the first secondary battery,
The first secondary battery and the second secondary battery so that the second secondary battery is positioned in a gap between the first secondary batteries adjacent to each other in the radial direction of the first secondary battery. Is an assembled battery that is arranged with their axes parallel to each other,
The second secondary battery is
Longer in the axial direction than the first secondary battery,
The battery capacity is made equal to the first secondary battery,
The above assembled battery
More than the number of the second secondary batteries arranged in the axial direction, a larger number of the first secondary batteries are arranged side by side in the axial direction,
An assembled battery in which the plurality of first secondary batteries and the plurality of second secondary batteries are all electrically connected in series. The assembled battery according to claim 1,
A plurality of the first secondary batteries, the length of the first battery row aligned in the axial direction,
The assembled battery in which the length of the 2nd battery row | line | column with which the one or several said 2nd secondary battery is arranged in the axial direction is made equal.

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