JP2008066093A - Battery module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery module capable of changing capacity easily. <P>SOLUTION: The battery module 10 includes a main unit 1 which has five pieces of unit cells, a connector in which voltage detecting wires in order to detect the respective voltages of the unit cells are gathered, and connections that are conducted to respective positive and negative terminals of the unit cells and are connectable to the outside at every unit cell, the unit cells of the same number as that of the main unit 1, and four sub units having the same number of unit cells as that the main unit 1 has. The respective unit cells of the main unit 1 are connected in series, the respective unit cells of the sub units 2 are not mutually connected, and the main unit 1 and the sub units 2, or the mutual sub units 2 are connected in parallel via the connections. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a battery module, and more particularly to a battery module in which a plurality of single cells are connected in series and parallel.

  Conventionally, in a battery power supply device using a secondary battery, generally, a plurality of secondary batteries (unit cells) are electrically connected in series and parallel to achieve higher voltage and higher capacity. For example, in an electric vehicle, a battery module in which a plurality of unit cells are connected in series and parallel corresponding to the required capacity is used.

  As a technique for assembling a plurality of single cells, a bus bar that is a conductive part is welded to a single cell and connected in series or in parallel, or a screw portion that is pre-processed on the positive and negative ends of the end is provided, Alternatively, it is known that a conductive member having a processed screw portion is fixed to a single cell by welding or the like, and a bus bar is fastened and fixed to these screw portions. These electrically connected assembled batteries (assembled batteries) are generally fixed by being held by a frame having insulation properties. There has been disclosed a battery module in which these assembled batteries are arranged adjacent to each other and a conducting member is attached to the adjacent assembled batteries to increase the voltage and capacity (for example, see Patent Document 1).

  On the other hand, in the battery module, when the capacity of each unit cell is different, the capacity of the unit cell is different. If the difference in capacity increases, the life of the unit cell is shortened and the usable voltage range is also narrowed. For this reason, it is common to use a cell controller to monitor the voltage of each unit cell and adjust the capacity of each unit cell to be substantially uniform. A technique for adjusting capacitance by connecting resistors in parallel via an element is known (for example, see Patent Document 2).

JP 2000-182583 A JP 2000-092732 A

  However, since the required capacity varies with the same voltage depending on the use of the battery module, it may be necessary to change the number of cells connected in parallel. In that case, since the cell controller required the voltage of the unit cell, it was necessary to design and manufacture the battery module for the required capacity each time.

  An object of the present invention is to provide a battery module whose capacity can be easily changed in view of the above case.

  In order to solve the above-described problems, the present invention provides a plurality of unit cells, an aggregation unit that aggregates voltage detection lines for detecting each voltage of the unit cells, or a cell controller connected to the voltage detection lines. , A main unit having two connection portions that are electrically connected to the positive and negative terminals of the unit cell and can be externally connected to each unit cell, the same number of unit cells as the main unit, and the unit cell plus , At least one subunit having two connecting portions that are electrically connected to each negative terminal and can be externally connected to each unit cell, and each unit cell of the main unit is connected in series, The single cells of the subunit are not connected to each other, and the main unit and the subunit or the subunits are connected in parallel via the connecting portion. To.

  The battery module of the present invention includes a plurality of unit cells, a cell controller connected to an aggregation unit or a voltage detection line that aggregates voltage detection lines for detecting each voltage of the unit cells, plus / minus unit cells A main unit having two connection portions that can be connected to each terminal and connected to the outside of each unit cell, the same number of unit cells as the main unit, and each unit cell connected to the positive and negative terminals of the unit cell And at least one subunit having two connection portions that can be externally connected to each other. The single cells of the main unit are connected in series, the single cells of the subunits are not connected to each other, and the main unit and the subunits or the subunits are connected in parallel via the connecting portion. In the present invention, it is possible to increase the number of subunits via the connection portion, and since the connection to the cell controller can be performed only by the main unit, it is possible to realize a battery module whose capacity can be easily changed. it can.

  If the number of connected subunits is large, a voltage difference tends to occur between the main unit cell and the terminal subunit cell due to electrical resistance. To reduce this voltage difference, multiple subunits are provided. In some cases, the main unit is preferably located in the center of the battery module. In addition, the two connecting portions of the main unit have a concave shape, and one of the two connecting portions of the subunit has a convex shape and the other has a concave shape, and the convex connecting portion is fitted into the concave connecting portion. If they are connected in parallel, the connection workability is improved and erroneous connection is easily prevented.

  Further, each of the main unit and the sub unit further has one electrically insulating plate, and this plate is arranged above the main unit and the sub unit so as to cover all the single cells of the main unit and the sub unit. By doing so, since the upper part of the battery module is electrically insulated by the plate, it is possible to prevent a short-circuit accident even when a conducting member is arranged on the upper part of the battery module. Furthermore, if all the unit cells of the main unit and the sub unit are respectively fixed to the plate, the unit cells can be prevented from floating. At this time, the connecting portion is located immediately below both sides in the longitudinal direction of the plate, and the plate has a portion corresponding to the concave connecting portion cut out, and an upper portion of the portion corresponding to the convex connecting portion is formed. It is preferable to project so as to cover. Also, if the voltage detection line is wired on the back side of the plate of the main unit, the voltage detection line is protected from external force from above by the plate, thus preventing disconnection. Furthermore, if the positive and negative output terminals are arranged on one side intersecting with the longitudinal direction of the plate of the main unit, it becomes easy to take out the electric power from the battery module.

  According to the present invention, it is possible to increase the number of subunits via the connection portion, and it is possible to connect to the cell controller only by the main unit, thus realizing a battery module whose capacity can be easily changed. Can be obtained.

  Hereinafter, an embodiment of a battery module according to the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the battery module 10 of the present embodiment is composed of one main unit 1 and four subunits 2, and the main unit 1 is located at the center of the battery module 10. Yes.

  As shown in FIG. 3, the main unit 1 includes five unit cells 3, an electrically insulating plate 4 covering the upper part of these unit cells 3, and a connector 8 fixed to one end portion in the longitudinal direction of the plate 4. The output terminal 7 is disposed close to the connector 8 and is erected on the plate 7.

  For the unit cell 3, for example, a positive electrode in which lithium manganese complex oxide is applied to an aluminum foil and a negative electrode in which amorphous carbon is applied to a rolled copper foil are wound through a separator so that the four corners are rectangular. The lithium ion secondary battery accommodated in the attached battery container can be used.

  As shown in FIG. 4, the main unit 1 includes five unit cells 3 connected in series by connection bus bars (conductive members) not shown. That is, the connection bus bar is spot-welded between terminals having different polarities between adjacent unit cells 3. Each connection bus bar is connected in advance with a voltage detection line 9 for detecting each voltage of the unit cell 3. As described above, the voltage detection lines 9 are gathered at one end in the longitudinal direction of the plate 4. Since the connector 8 is fixed in advance, the voltage detection line 9 needs some play (length) for connecting the connection bus bar, but the individual connection between the connector 8, the voltage detection line 9, and the unit cell 3. No connection work is required.

  In addition, one end side of the output line 13 is connected in advance to the output terminal 7 on the back side of the plate 4, and the other end side of the output line 13 is connected to the minus terminal of the cell 3 on the lowest potential side and the single terminal on the highest potential side, respectively. It is connected in advance to a bus bar spot welded to the positive terminal of the battery 3. Therefore, as with the voltage detection line 9, the voltage line 13 requires some play for connection work, but does not require individual connection work. The voltage detection line 9 and the output line 13 are wired above the unit cell 3 constituting the main unit 1 and on the back side of the plate 4, and are covered by the plate 4 after the battery module 10 is assembled (the plate 4 Protected from the outside). Note that a cable having a large maximum allowable current and a small resistance is used for the output line 13 in consideration of parallel connection (addition) of the subunits 2 as will be described later.

  Each unit cell 3 has two concave connection portions 5 that are electrically connected to the plus and minus terminals and can be externally connected to each unit cell 3 (see also FIG. 3). In the present embodiment, in order to reduce wiring, two concave connection portions 5 are connected to the positive and negative terminals inside the unit cell 3, but the concave shape is formed from each terminal outside the unit cell 3. You may make it connect to the connection part 5, respectively.

  As shown in FIG. 3, the five unit cells 3 are fixed to the plate 4. As this fixing mode, for example, a (female) screw hole is formed in the upper center of each unit cell 3 and fixed with a fixing (male) screw through a round hole formed in a corresponding portion of the plate 4. In addition, grooves are previously formed at a plurality of positions on the upper part of each unit cell 3, and protrusions that fit into the grooves are formed at corresponding positions on the plate 4, and an adhesive is applied to the protrusions to fit into the grooves. Then, the single cells 3 can be fixed to the plate 4 by solidifying.

  The concave connection portion 5 described above is located immediately below both sides in the longitudinal direction of the plate 4, and a portion corresponding to the concave connection portion 5 of the plate 4 is cut out in the same shape as the cross-sectional shape of the concave connection portion 5. . Further, a concave fitting portion 11 is formed between the concave connection portions 5 of each unit cell 3 in a concave shape, and a cross-sectional area of the cutout is smaller than the concave connection portion 5.

  On the other hand, as shown in FIGS. 5 and 6, the subunit 2 has five unit cells 3 and an electrically insulating plate 4 ′ covering the upper part of these unit cells 3. 1 has the same structure as that of the main unit 1, but differs from the main unit 1 in the following points.

  First, as shown in FIG. 6, the unit cells 3 of the subunit 2 are not connected to each other. Further, unlike the main unit 1, the output terminal 7 and the connector 8 are not provided, and therefore the voltage detection line 9 and the output line 13 are not wired on the back side of the plate 4 '.

  In addition, as shown in FIG. 5, each unit cell 3 is the same as the main unit 1 in that it has two connection portions that are electrically connected to the plus and minus terminals and can be externally connected to each unit cell 3. The main connection is that one of the two connection portions that can be externally connected to each unit cell 3 has the same concave connection portion 5 as the main unit 1 and the other has the convex connection portion 6. It is different from unit 1.

  For this reason, although the location corresponding to the concave connection portion 5 of the plate 4 ′ is cut out in the same shape as the cross-sectional shape of the concave connection portion 5, the location corresponding to the convex connection portion 6 is the convex connection portion 6. It protrudes so as to cover the upper part of the concave connection portion 6 in the same shape as the cross-sectional shape. In addition, the convex connection part 6 and the concave connection part 5 are located directly below one side and the other side in the longitudinal direction of the plate 4 ′. In addition, a concave fitting portion 11 is formed between the concave connection portions 5 of each unit cell 3 in a concave shape, and a sectional area of the notch is smaller than the concave connection unit 5. A convex fitting portion 12 that protrudes in a convex shape between the convex connecting portions 6 and has a smaller cross-sectional area than the convex connecting portion 6 is formed.

  As shown in FIGS. 1 and 2, the main unit 1 and the subunit 2 or the subunits 2 are fitted to the concave connection portion 5 with the convex connection portion 6, and the concave fitting portion 11 with the convex fitting portion 12. By combining, the battery module 10 is configured in parallel. In other words, as for the connection part of the main unit 1 and the subunit 2, the connection part of the unit to be added has a concave shape, and the connection part of the unit to be added has a convex shape. This relationship is the same between the concave fitting portion 11 and the convex fitting portion 12.

  Next, effects and the like of the battery module 10 of the present embodiment will be described.

  The battery module 10 according to this embodiment includes five cells 3, a connector 8 that aggregates voltage detection lines 9, and two locations that can be connected to the positive and negative terminals of the cell 3 and connected externally for each cell 3. Main unit 1 having the same number of concave connection parts 5, the same number of unit cells 3 as the main unit, the concave connection part 5 that is electrically connected to the positive and negative terminals of the unit cell 3 and can be externally connected to each unit cell 3, and the convex shape And four subunits 2 each having a connection portion 6. The unit cells 3 of the main unit 1 are connected in series, the unit cells 3 of the subunit 2 are not connected to each other, and the main unit 1 and the subunit 2 or the subunits 2 are connected to each other with a concave connection portion 5 and a convex shape. They are connected in parallel via the connection unit 6. According to the present embodiment, the number of parallel connections of the subunits 2 can be increased via the concave connection portion 5 and the convex connection portion 6, and the connection to the cell controller is performed only by the main unit 1 by the connector 8. Therefore, it is possible to change the parallel number without considering the additional portion (subunit 2). For this reason, the battery module which can change a capacity | capacitance easily is realizable.

  In the present embodiment, the main unit 1 is arranged in the center of the battery module 10. For this reason, even when the number of parallel connections of the subunits 2 is large, the voltage difference between the unit cell 3 of the main unit 1 and the unit cell 3 of the subunit 2 of the terminal caused by the electrical resistance in the connection part or unit cell 3 Can be reduced.

  Furthermore, in this embodiment, two connection parts for each unit cell 3 of the main unit 1 have a concave shape, and one of the two connection parts for each unit cell 3 of the subunit 2 is convex, and the other is concave. Since the convex connection part 6 is fitted to the concave connection part 5 in one-touch and connected in parallel, the connection workability is improved and erroneous connection is easily prevented.

  Furthermore, in the present embodiment, the main unit 1 and the subunit 2 further include plates 4 and 4 ′, respectively, so that the plates 4 and 4 ′ cover all the single cells 3 of the main unit 1 and the subunit 2. Are disposed above the main unit 1 and the subunit 2. Further, the plate 4, 4 ′ is cut out at a portion corresponding to the concave connection portion 5, and protrudes so as to cover an upper portion of the portion corresponding to the convex connection portion 6. For this reason, since the upper part of the battery module 10 is electrically insulated by the plates 4 and 4 ′ after the parallel connection, it is possible to prevent a short-circuit accident even when a conductive member is disposed on the upper part of the battery module 10. it can.

  Further, in this embodiment, all the single cells 3 of the main unit 1 and the subunit 2 are fixed to the plates 4 and 4 ′, respectively. For this reason, even if an external force such as vibration is applied to the battery module 10, the unit cell 3 can be prevented from floating. In addition, each unit cell 3 is rectangular and regulates the movement of each other. In addition, since the main unit 1 and the subunit 2 are fitted and integrated through the connection portion and the fitting portion, the entire battery module 10 has a structure that does not vibrate or play against external force. Yes.

  In the present embodiment, since the voltage detection line 9 and the output line 13 are wired on the back side of the plate 4 of the main unit 1, the voltage detection line 9 and the output line 13 are protected from the external force from above by the plate 4. This will prevent disconnection.

  Furthermore, in this embodiment, the connector 8 and the output terminal 7 are arranged on one side that intersects the longitudinal direction of the plate 4 of the main unit 1. For this reason, the connection to the cell controller, the connection for taking out the power, and the like can be performed at a single location.

  In the present embodiment, the connector 8 for collecting and connecting the voltage detection lines 9 to the cell controller is illustrated. However, the present invention is not limited to this, and the voltage detection lines 9 are directly connected to the cell controller. May be. In this case, the cell controller may be disposed, for example, above the plate 4 of the main unit 1.

  Further, in the present embodiment, the one-touch fitting of the concave connection portion 5 and the convex connection portion 6 is illustrated as the connection between the main unit 1, the subunit 2 and the subunits 2, but the present invention is not limited to this and is connected The part may be bolted. Further, the connection form may be selected in accordance with the required power and use form (for example, whether or not vibrations should be taken into consideration as in a vehicle-mounted power supply).

  Furthermore, in this embodiment, although the concave connection part 5 was illustrated in the main unit 1, and the concave connection part 5 and the convex connection part 6 were illustrated in the subunit 2, this invention is not restrict | limited to this. In short, the connecting portion of the main unit 1 and the subunit 2 may have a shape that can be connected so as not to make a mistake between plus and minus.

  In the present embodiment, an example is shown in which the upper side of the concave connection portion 6 of the terminal subunit 2 at the end is exposed. In order to further enhance safety, this portion is covered with an insulating member such as a plate. Alternatively, the dummy concave connection portion may be fitted to completely prevent an external short-circuit accident on the upper side of the battery module 10.

  And in this embodiment, although the wound-type lithium ion secondary battery was illustrated as the single battery 3, this invention is not restricted to this, For example, you may use a laminated lithium ion secondary battery, Is not limited to a lithium ion secondary battery, and other secondary batteries such as a nickel hydride secondary battery may be used.

  Since the present invention provides a battery module whose capacity can be easily changed, it contributes to the manufacture and sale of battery modules, and thus has industrial applicability.

It is an external appearance perspective view of the battery module of embodiment which can apply this invention. It is a disassembled perspective view of the battery module of an embodiment. It is a fragmentary perspective view of the main unit which comprises a battery module. It is a wiring diagram of a main unit. It is a fragmentary perspective view of the subunit which comprises a battery module. It is a wiring diagram of a subunit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main unit 2 Sub unit 3 Single cell 4 Plate 5 Concave connection part 6 Convex connection part 7 Output terminal 9 Voltage detection line 10 Battery module

Claims (8)

A plurality of single cells, an aggregation unit that collects voltage detection lines for detecting each voltage of the single cells, or a cell controller connected to the voltage detection lines, and positive and negative terminals of the single cells A main unit having two connection portions which are electrically connected and can be externally connected to each unit cell;
At least one subunit having the same number of unit cells as the main unit, and two connection portions that are electrically connected to the positive and negative terminals of the unit cell and can be externally connected to each unit cell;
The single cells of the main unit are connected in series, the single cells of the subunit are not connected to each other, and the main unit and the subunit or the subunits are connected via the connecting portion. A battery module characterized by being connected in parallel.   A plurality of the subunits are provided, and the main unit and the subunits or the subunits are connected in parallel via the connecting portion so that the main unit is located at the center of the battery module. The battery module according to claim 1.   The two connecting portions of the main unit have a concave shape, and one of the two connecting portions of the subunit has a convex shape and the other has a concave shape. The main unit and the sub unit or the sub unit 3. The battery module according to claim 1, wherein the units are connected in parallel by fitting the convex connection portion into the concave connection portion.   Each of the main unit and the sub unit further includes a single electrically insulating plate, and the plate is disposed on the main unit and the sub unit so as to cover all the single cells of the main unit and the sub unit. The battery module according to claim 3, wherein the battery module is provided.   The battery module according to claim 4, wherein all the single cells of the main unit and the subunit are fixed to the plate.   The connecting portion is located immediately below both sides in the longitudinal direction of the plate, and the plate has a cutout portion corresponding to the concave connecting portion, and a portion corresponding to the convex connecting portion. The battery module according to claim 4, wherein the battery module protrudes so as to cover an upper part.   The battery module according to claim 4, wherein the voltage detection line is wired on the back side of the plate of the main unit.   5. The battery module according to claim 4, wherein positive and negative output terminals are arranged on one side intersecting a longitudinal direction of the plate of the main unit.

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