JP2015204281A - battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module capable of highly accurately detecting voltage of battery cells constituting a battery stack.SOLUTION: There is provided a battery module comprising: a battery stack in which a plurality of battery cells are laminated; a substrate arranged on an upper surface of the battery stack; battery monitoring means mounted on the substrate and for monitoring a battery cell state; and a bus bar formed by processing a metal wire and connecting the electrodes of the battery cells and the substrate. The bus bar comprises a bus bar part having a long hole shape in which a lamination direction of the battery stack is a long side or a long diameter and including an insertion hole into which the electrode is inserted, and a lead-out part connecting the bus bar part and the substrate. The lead-out part comes into contact with a fastening part fastening the electrode and the bus bar part.

Description

  The present invention relates to a battery module.

  Conventionally, in a battery stack in which a plurality of battery cells are connected in series via a bus bar, a configuration in which a detection line is arranged on the bus bar and the state of each battery cell is monitored using battery monitoring means connected to the detection line It has been known.

  Further, a technology has been disclosed in which the shape of the insertion hole through which the electrode terminal is inserted is a long hole or a long groove in the bus bar connected to the electrode terminal of the battery cell (see, for example, Patent Document 1).

JP 2006-128116 A

  However, in the technique described in Patent Document 1, the positional relationship between the fastening portion between the electrode terminal and the bus bar and the detection line is not described. Further, if the shape of the insertion hole through which the electrode terminal is inserted is a long hole or a long groove, the resistance between the electrode terminal and the detection line may vary greatly depending on each battery cell. As a result, the voltage of the battery cell that constitutes the battery stack may not be detected accurately.

  Accordingly, an object of the present invention is to accurately detect the voltage of the battery cells constituting the battery stack.

  In one proposal, a battery stack in which a plurality of battery cells are stacked, a substrate disposed on an upper surface of the battery stack, battery monitoring means mounted on the substrate and monitoring the state of the battery cells, and a metal wire A bus bar that connects the electrode of the battery cell and the substrate, and the bus bar has a long hole shape with a long side or a long diameter in the stacking direction of the battery stack, and the electrode A bus bar portion including an insertion hole through which is inserted, and a lead portion for connecting the bus bar portion and the substrate, the lead portion contacting a fastening portion for fastening the electrode and the bus bar portion. A battery module is provided.

  According to one aspect, it is possible to accurately detect the voltage of the battery cells constituting the battery stack.

The schematic block diagram of an example of the battery module which concerns on this embodiment. The figure for demonstrating an example of the bus-bar which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, the duplicate description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  First, a schematic configuration of an example of the battery module 1 according to the present embodiment will be described. FIG. 1 is a schematic configuration diagram of an example of a battery module 1 according to the present embodiment. FIG. 2 is a view for explaining an example of the bus bar 20 according to the present embodiment. More specifically, FIG. 2A shows the metal wire 20r before being processed as the bus bar 20, and FIGS. 2B and 2C show the bus bar 20 formed by processing the metal wire 20r. .

  As shown in FIG. 1, the battery module 1 includes a battery stack 10, a bus bar 20, a smoke exhaust duct 40, a substrate 50, a battery monitoring unit 60, and the like.

  The battery stack 10 is, for example, an assembled battery in which a plurality of battery cells 11 are arranged (stacked) in one direction along the X direction in FIG.

  The battery cell 11 has, for example, a rectangular parallelepiped shape whose longitudinal direction is the Y direction in FIG. In the vicinity of both ends in the longitudinal direction of the upper surface of the battery cell 11, electrode terminals 12 as a pair of electrodes are provided so as to protrude. The pair of electrode terminals 12 are, for example, a positive electrode terminal and a negative electrode terminal of the battery cell 11. Adjacent battery cells 11 constituting the battery stack 10 are arranged such that, for example, the positions of the positive electrode terminal and the negative electrode terminal are reversed. Examples of the type of the battery cell 11 include a nickel metal hydride battery and a lithium ion battery, but the present invention is not limited in this respect.

  The separator 14 is arrange | positioned between the mutually adjacent battery cells 11, and hold | maintains the adjacent battery cells 11 at a fixed space | interval. A space is formed between the separator 14 and the battery cell 11. The battery cell 11 is cooled by blowing a cooling medium such as air into the space. Examples of the separator 14 include those formed by molding an insulating member such as plastic, but the present invention is not limited in this respect.

  The bus bar 20 is formed by processing a metal wire 20r as a base wire shown in FIG. 2A, and connects the electrode terminal 12 and the substrate 50.

  The metal wire 20r is preferably a member that can be bent freely according to the shape of the battery cell 11, the shape of the electrode terminal 12, and the like. For example, a highly conductive conductive metal such as copper or aluminum is preferably used. be able to. Thereby, even when the shape of the battery cell 11, the shape of the electrode terminal 12, etc. are changed, the bus bar 20 can be formed without changing the metal wire 20r. As a result, parts management becomes easy and parts costs can be reduced.

  In addition, the bus bar 20 includes a bus bar portion 20a, a drawer portion 20b, and a fastening portion 20c, as shown in FIGS. 2 (b) and 2 (c).

  The bus bar portion 20a has a long hole-shaped insertion hole 20h having a long side or a long diameter in the stacking direction of the battery cells 11 in the battery stack 10. Then, the electrode terminal 12 is inserted into the insertion hole 20h formed in the bus bar portion 20a, and the bus bar portion 20a is fastened to and connected to the electrode terminal 12 by being fixed by, for example, a tightening nut or welding. The shape of the insertion hole 20h is not particularly limited as long as the electrode terminal 12 can be inserted, and is a long hole shape having a long side or a long diameter in the stacking direction of the battery cells 11 in the battery stack 10, for example, a rectangle or a rounded corner A long hole shape such as a rectangle or an ellipse may be mentioned.

  The lead portion 20b extends from the bus bar portion 20a and connects the bus bar portion 20a and the substrate 50. That is, one end of the lead-out portion 20b is connected to the bus bar portion 20a so as to contact a fastening portion 20c described later. The other end of the lead-out portion 20b is connected to the battery monitoring means 60 via a wiring pattern (not shown) formed on the substrate 50 described later. In addition, since the bus bar 20 including the lead portion 20b is formed by processing the metal wire 20r, the position of the lead portion 20b can be changed according to the position of the electrode terminal 12 inserted through the insertion hole 20h. it can.

  As shown in FIGS. 2B and 2C, the fastening portion 20c is a portion where the electrode terminal 12 and the bus bar portion 20a are in contact with or close to each other.

  The smoke exhaust duct 40 is disposed on the upper surface of the battery stack 10 and extends in the stacking direction of the battery cells 11 in the battery stack 10. The cooling medium is forcibly blown into the smoke exhaust duct 40 by, for example, a blowing means (not shown). For this reason, the battery cell 11 is cooled by the cooling medium flowing through the smoke exhaust duct 40.

  The substrate 50 is disposed on the upper surface of the battery stack 10 via the smoke exhaust duct 40. As described above, the drawer portion 20b of the bus bar 20 is connected to the substrate 50. In addition, electronic components such as battery monitoring means 60 are mounted on the substrate 50. And the drawer | drawing-out part 20b of the bus bar 20 and the battery monitoring means 60 are electrically connected on the board | substrate 50 through the wiring pattern, for example. Examples of the substrate 50 include a resin substrate provided with a wiring pattern, but the present invention is not limited in this respect.

  The battery monitoring means 60 is mounted on the substrate 50 as described above, and is connected to the lead-out portion 20b of the bus bar 20 via a wiring pattern formed on the substrate 50. Then, the battery monitoring unit 60 calculates the voltage of the battery cell 11 based on the potential of the electrode terminal 12 of the battery cell 11 detected through the bus bar part 20a and the lead part 20b of the bus bar 20. Examples of the voltage calculation method include a method of calculating the voltage of the battery cell 11 by subtracting the potential of the negative electrode terminal from the detected potential of the positive electrode terminal of the battery cell 11. This is not a limitation. Examples of the battery monitoring means 60 include a monitoring ECU (Electronic Control Unit), but the present invention is not limited in this respect.

  Next, the operation of the battery module 1 according to this embodiment will be described.

  In the battery module 1 according to the present embodiment, the electrode terminal 12 is inserted into the insertion hole 20h having a long hole shape of the bus bar portion 20a, and is fixed by, for example, a tightening nut, welding, or the like, whereby the bus bar portion 20a is connected to the electrode terminal 12. It is possible to connect with. Therefore, even when the position of the electrode terminal 12 is shifted due to expansion of each battery cell 11 constituting the battery stack 10, variation in a stacking process (assembly process) for stacking the plurality of battery cells 11, or the like. The bus bar 20 can be easily connected to the electrode terminal 12.

  By the way, when the insertion hole 20h of the bus bar portion 20a has a long hole shape, the resistance between the electrode terminal 12 and the bus bar 20 varies depending on the positional relationship between the electrode terminal 12 and the fastening portion 20c. The voltage may not be detected accurately.

  However, in the battery module 1 according to the present embodiment, one end of the drawer portion 20b is connected to the bus bar portion 20a so as to contact the fastening portion 20c. That is, as shown in FIG. 2B, when the electrode terminal 12 is disposed in the vicinity of the center portion of the insertion hole 20h, one end of the lead portion 20b is in the vicinity of the fastening portion 20c (near the center portion of the insertion hole 20h). The bus bar 20 is formed by bending the metal wire 20r so as to be positioned at the position. Further, as shown in FIG. 2C, when the electrode terminal 12 is disposed in the vicinity of the end portion of the insertion hole 20h, the lead-out portion 20b is positioned in the vicinity of the fastening portion 20c (near the end portion of the insertion hole 20h). The metal bar 20r is bent so as to form the bus bar 20. For this reason, in each battery cell 11, even if the positional relationship between the electrode terminal 12 and the fastening portion 20c is different, the positional relationship between the electrode terminal 12 and the lead-out portion 20b is the same or substantially the same. As a result, in each battery cell 11, variation in resistance between the electrode terminal 12 and the bus bar 20 can be suppressed, and the voltage of the battery cell 11 constituting the battery stack 10 can be detected with high accuracy.

  In the above example, the case where one insertion hole 20h is formed in the bus bar portion 20a has been described, but the present invention is not limited in this respect. For example, a plurality of insertion holes 20 h can be formed in one bus bar 20 and the electrode terminals 12 of the plurality of battery cells 11 can be electrically connected to each other. In this case, for example, a number of insertion holes 20h corresponding to the number of battery cells 11 may be formed in the bus bar 20, and a plurality of lead-out portions 20b may be formed so as to contact each fastening portion 20c. . Further, for example, the bus bar 20 is formed with a number of insertion holes 20h corresponding to the number of the battery cells 11, and one drawer portion 20b is formed so as to be in contact with one fastening portion 20c of each fastening portion 20c. It can also be.

  Moreover, according to the battery module 1 which concerns on this embodiment, the bus-bar 20 is formed by processing the metal wire 20r. For this reason, even when the shape of the battery cell 11, the shape of the electrode terminal 12, etc. are changed, the bus bar 20 can be formed without changing the metal wire 20r. As a result, parts management becomes easy and parts costs can be reduced.

  As described above, the battery module 1 according to the present embodiment is mounted on the battery stack 10 in which the plurality of battery cells 11 are stacked, the substrate 50 disposed on the upper surface of the battery stack 10, and the substrate 50. A battery monitoring means 60 for monitoring the state of the battery cell 11 and a bus bar 20 formed by processing the metal wire 20r and connecting the electrode of the battery cell 11 and the substrate 50 are provided. The bus bar 20 has a long hole shape having a long side or a long diameter in the stacking direction of the battery stack 10, and connects the bus bar portion 20 a including the insertion hole 20 h through which the electrode is inserted, and the bus bar portion 20 a and the substrate 50. And a drawer portion 20b. And the drawer | drawing-out part 20b contacts the fastening part 20c which fastens an electrode and the bus-bar part 20a. Thereby, the voltage of the battery cell 11 which comprises the battery stack 10 can be detected accurately.

  As mentioned above, although the battery module 1 was demonstrated by embodiment, this invention is not limited to the said embodiment, A various deformation | transformation and improvement are possible within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Battery module 10 Battery stack 11 Battery cell 12 Electrode terminal 20 Bus bar 20a Bus bar part 20b Lead part 20c Fastening part 20h Insertion hole 20r Metal wire 50 Substrate 60 Battery monitoring means

Claims (1)

A battery stack in which a plurality of battery cells are stacked;
A substrate disposed on an upper surface of the battery stack;
Battery monitoring means mounted on the substrate and monitoring the state of the battery cell;
A bus bar formed by processing a metal wire, and connecting the electrode of the battery cell and the substrate;
The bus bar
A bus bar portion having a long hole shape or a long diameter in the stacking direction of the battery stack, and including an insertion hole through which the electrode is inserted;
A drawer portion connecting the bus bar portion and the substrate;
The lead portion is in contact with a fastening portion that fastens the electrode and the bus bar portion,
Battery module.

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