JP2013098031A - Mounting structure of thermistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify mounting work in a mounting structure of a thermistor.SOLUTION: The mounting structure of the thermistor includes a flexible printed board 30 arranged in a unit cell group 10, which has a main body part 31 that is arranged along an aligning direction of a plurality of unit cells 11 and has a conductive path 32 formed therein that is arranged so as to extend in the aligning direction of the unit cells 11. The flexible printed board 30 has lead-in pieces 33 integrally provided with the main body part 31, which have lead-in wire parts 34 that continue from one terminal of a conductive path 32A and are introduced between adjacent unit cells 11, and thermistors 35 mounted on the lead-in wire parts 34. In the mounting structure of the thermistor 35, the thermistors 35 are mounted on the unit cell group 10 by inserting the lead-in pieces 33 between the adjacent unit cells 11.

Description

  The present invention relates to a thermistor mounting structure.

  In battery modules for electric vehicles and hybrid vehicles, a large number of single cells are connected side by side in order to increase the output. A plurality of unit cells are connected in series or in parallel by connecting electrode terminals of adjacent unit cells with a connecting member such as a bus bar.

  By the way, if the battery module is used in a high temperature state, the life may be reduced, and a battery module formed by connecting a plurality of lithium ion batteries or the like may ignite due to a high temperature during charging. Therefore, in order to avoid such a situation, a temperature sensor for detecting the battery temperature is attached to the battery module (see, for example, Patent Document 1).

Japanese Patent No. 4540429

  In Patent Document 1, a configuration is proposed in which a temperature sensor is fixed to a printed circuit board, and the temperature sensor is disposed through a case that houses a battery module.

  However, in the battery module having such a configuration, it is necessary to pass the temperature sensor through the case, and since the temperature sensor is connected to the printed circuit board through the lead wire, when connecting the temperature sensor, There is a problem that it is necessary to perform solder connection, which is troublesome.

  The present invention has been completed based on the above circumstances, and an object thereof is to simplify the thermistor mounting operation for detecting the temperature.

  The present invention is a mounting structure of a thermistor attached to a unit cell group formed by connecting a plurality of unit cells side by side, and the unit cell group is arranged along the arrangement direction of the unit cells, and A flexible printed circuit board having a main body formed with a conductive path extending in the direction in which the cells are arranged is arranged, and the flexible printed circuit board is connected to one end of the conductive path and is adjacent to the single cell. An introduction piece including an introduction line portion introduced between and a thermistor mounted on the introduction line portion is provided integrally with the main body portion, and the introduction piece is inserted between adjacent unit cells. In this way, the thermistor is attached to the unit cell group.

  In the present invention, a flexible printed circuit board provided with a main body part in which a conductive path is formed, an introduction line part continuous from one end of the conduction path and a thermistor mounted on the introduction line part is provided as a unit cell. A thermistor can be attached simply by arranging in a group and introducing an introduction piece between adjacent cells. Therefore, according to the present invention, the thermistor mounting operation can be simplified.

The present invention may have the following configuration.
The thermistor may be a chip type. With such a configuration, the component cost can be reduced as compared with a case where a temperature sensor connected by a lead wire is provided.

A separator disposed between the adjacent single cells may be provided, and the separator may be provided with an introduction piece receiving hole capable of receiving the introduction piece of the flexible printed circuit board.
With such a configuration, when the case of the unit cell is made of metal and a short circuit may occur due to contact between the cases, the introduction piece of the flexible printed circuit board is disposed between the unit cells while preventing the occurrence of a short circuit. Can be held in.

The flexible printed circuit board is provided with a voltage detection terminal portion that detects the voltage of the unit cell, and a detection conductive path that is connected to the voltage detection terminal portion to form a voltage detection circuit, and the voltage detection terminal The part may be connected to the unit cell.
With such a configuration, it is possible to assemble both the temperature control circuit and the voltage detection circuit by attaching only one flexible printed circuit board, so that the assembly work can be simplified and the number of parts can be reduced. You can also.

  According to the present invention, the mounting work can be simplified in the thermistor mounting structure.

The perspective view of the battery module of Embodiment 1. Plan view of battery module Partial sectional view showing the connection state of electrode terminals of adjacent unit cells Partial sectional view taken along line AA in FIG. Partial plan view of the battery module Partial sectional view taken along line BB in FIG. Partially enlarged sectional view of FIG. The perspective view explaining a mode that a flexible printed circuit board is attached to a cell group Partial sectional view in the state shown in FIG. 9 is a partially enlarged sectional view of FIG.

<Embodiment>
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of a battery module M according to an embodiment of the present invention. The battery module M of this embodiment is mounted on an electric vehicle, a hybrid vehicle, or the like, and is used as a driving power source. As shown in FIG. 1, the battery module M includes a unit cell group 10 and a flexible printed circuit board 30 (hereinafter also referred to as FPC 30). In the following description, the upper part of FIG.

  In the present embodiment, the unit cell group 10 includes a plurality of (in the present embodiment, 24) unit cells 11 arranged in a line and connected in series. Specifically, the unit cell 11 constituting the unit cell group 10 is composed of two types of unit cells 11A and 11B in which the extending directions of the electrode terminals 20 are different from each other. These two types of unit cells 11A and 11B are alternately arranged. The unit cell group 10 is configured by arranging and connecting.

  The unit cell 11 </ b> A includes a flat rectangular parallelepiped case 12 and a pair of positive and negative electrode terminals 20 (20 </ b> A, 20 </ b> B) protruding upward from the upper surface of the case 12.

  In the case 12, for example, a battery element (not shown) constituting a well-known lithium ion battery is accommodated, and the positive electrode side of the battery element is connected to the electrode terminal 20A and the negative electrode side is connected to the electrode terminal 20B.

  Of the pair of electrode terminals 20 of the unit cell 11A (see the second unit cell 11A from the left end in FIG. 1), one electrode terminal 20A on the near side in FIG. 1 is the positive electrode terminal 20A (positive terminal 20A). The other electrode terminal 20B on the back side is a negative electrode terminal 20B (negative electrode terminal 20B).

  Both the positive electrode terminal 20 </ b> A and the negative electrode terminal 20 </ b> B are made of a thin metal plate material that can be bent and deformed in the direction in which the cells 11 are arranged. As shown in FIGS. 1 and 3, the positive terminal 20 </ b> A has a rising portion 21 </ b> A that protrudes upward from the upper surface of the case 12, and is flat toward the front side (the left side in the drawing) by bending in an L shape from the upper end of the rising portion 21 </ b> A. 22 A of surface parts and the operation part 23 which inclines forward at the front-end | tip of the flat end part 22A are provided.

  As shown in FIGS. 1 and 3, the negative electrode terminal 20 </ b> B has a rising portion 21 </ b> B that protrudes upward from the upper surface of the case 12 of the unit cell 11, and is bent in an L shape from the upper end of the rising portion to the far side (right side in the drawing). And a flat surface portion 22 </ b> B heading toward. The flat surface portion 22B of the negative electrode terminal 20B is a portion that is electrically connected to the positive electrode terminal 20A of the adjacent unit cell 11.

  In the negative electrode terminal 20B, the bending position is set so that the flat surface portion 22B is disposed below the flat surface portion 22A of the positive electrode terminal 20A as shown in FIG.

  As shown in FIG. 1, an insulating partition wall 15 is erected at a position adjacent to the negative electrode terminal 20 </ b> B on the upper surface of the case 12. The insulating partition 15 is set wider than the lateral width of the negative electrode terminal 20B, and a short circuit caused by a tool or member made of a conductive material falling between the electrode terminals 20A and 20B of different polarities of the adjacent unit cells 11 falls. It is preventing.

  A spring member 24 is attached to the flat surface portion 22A of the positive electrode terminal 20A. The spring member 24 is integrally provided with a holding spring portion 25 that receives and holds the flat surface portion 22B of the negative electrode terminal 20B, and an auxiliary spring portion 26 that receives and holds an extension piece 36 (details will be described later) of the FPC 30. It is a member. The spring member 24 is formed by pressing a metal plate that is separate from the positive electrode terminal 20 </ b> A and has excellent spring properties such as stainless steel.

  The sandwiching spring portion 25 is formed by forming a slit 25A extending in the width direction of the plate at one end of the metal plate, and turning the other end of the metal plate toward the slit 25A. The operation portion 23 of the positive electrode terminal 20A is penetrated through the slit 25A of the holding spring portion 25, and a single portion is provided between the flat surface portion 22A of the positive electrode terminal 20A and the inner peripheral edge of the lower side of the slit 25A of the holding spring portion 25. An insertion port 25B that receives the flat surface portion 22B of the negative electrode terminal 20B is formed along the direction in which the batteries 11 are arranged. When the flat surface portion 22B of the negative electrode terminal 20B is inserted into the insertion port 25B, the flat surface portion 22A of the positive electrode terminal 20A is pressed against the case 12 side (lower side) by the elastic force of the holding spring portion 25, and the negative terminal 20B It is pressed against the upper surface of the flat surface portion 22B.

  As shown in FIG. 4, the auxiliary spring portion 26 has a configuration in which the configuration of the holding spring portion 25 is reduced in the width direction. Specifically, the auxiliary spring portion 26 is provided in parallel with the operation portion 23 of the positive electrode terminal 20A. The operation part 27 is made to penetrate through an auxiliary slit 26 </ b> A provided in the auxiliary spring part 26. In the auxiliary spring portion 26, an auxiliary insertion port 26B that receives the extending piece 36 of the FPC 30 is formed between the auxiliary operation portion 27 of the positive electrode terminal 20A and the lower inner periphery of the auxiliary slit 26A.

  The sandwiching spring portion 25 and the auxiliary spring portion 26 are arranged so that the insertion port 25B does not open in conjunction with the opening of the auxiliary insertion port 26B, and conversely, the auxiliary insertion port in conjunction with the opening of the insertion port 25B. The slit 25A and the auxiliary slit 26A are separated by notching (notched portion 28) so that 26B does not open.

  Between the pair of positive and negative electrode terminals 20, a synthetic resin substrate mounting portion 16 on which the FPC 30 is mounted is provided so as to protrude upward. The substrate platform 16 includes a main body platform 16A on which the main body 31 of the FPC 30 is placed, and an extended piece platform 16B on which the extended piece 36 of the FPC 30 is placed. . The height of the substrate mounting portion 16 is set to be substantially the same as the height of the auxiliary insertion port 26B of the auxiliary spring portion 26, and the height of the substrate mounting portion 16 is set to the auxiliary insertion port 26B without bending the extending piece 36 of the FPC 30. It can be inserted.

  The basic configuration of the unit cell 11B is the same as that of the unit cell 11A described above, and includes a case 12 and a pair of positive and negative electrode terminals 20A and 20B. However, in the unit cell 11B and the unit cell 11A, the directions in which the flat surface portions 22A and 22B of the electrode terminals 20A and 20B are bent in an L shape are reversed.

  A separator 17 made of an insulating resin is disposed between the adjacent unit cells 11A and 11B. As shown in FIG. 6, the separator 17 is provided with an introduction piece receiving hole 18 into which the introduction piece 33 of the FPC 30 can be inserted.

  Although the FPC 30 attached to the unit cell group 10 is not shown in detail, a plurality of conductive paths 32 are formed by a printed wiring technique on one or both sides of an insulating base film made of, for example, a polyimide film or a liquid crystal film. (See FIGS. 5 and 8), the surface of the conductive path 32 is covered with a protective film (for example, a polyimide film). 5 shows only the conductive path 32B (an example of the detection conductive path 32B) constituting the voltage detection circuit, FIG. 8 shows only the conductive path 32A constituting the temperature control circuit, and other figures show the conductive path. The illustration of the path 32 is omitted.

  The FPC 30 includes a strip-shaped (long-shaped) main body 31 (referred to as an FPC main body 31), a plurality of extending pieces 36 extending from the end in the width direction of the FPC main body 31, and the FPC main body 31. And two introduction pieces 33 provided substantially at the center.

  As shown in FIG. 2, the FPC main body portion 31 is placed on the main body placement portion 16 </ b> A of the substrate placement portion 16 and is disposed along the arrangement direction of the cells 11. In the FPC main body 31, a plurality of detection conductive paths 32B for voltage detection circuits and two conductive paths 32A for temperature control circuits are formed so as to extend in the direction in which the cells 11 are arranged (FIG. 5 and FIG. 8).

  The introduction piece 33 is provided by forming a rectangular cut at a substantially central portion in the width direction of the FPC main body 31 and has a rectangular shape. Each of the two introduction pieces 33 is provided with an introduction line portion 34 connected from one end of the temperature control conductive path 32A. A chip type NTC thermistor 35 is mounted on each lead-in portion 34. Each introduction piece 33 is inserted between adjacent unit cells 11A and 11B. In this embodiment, one introduction piece 33 is inserted for every eight unit cells 11. The introduction piece 33 inserted between the single cells 11 is received and accommodated in the introduction piece receiving hole 18 provided in the separator 17 (see FIGS. 6 and 7). The other terminal of the temperature control conductive path 32A is connected to an ECU (not shown). Information on the temperature obtained by the thermistor 35 is taken into the ECU through the lead-in portion 34 and the conductive path 32A, and the temperature of each unit cell 11 is detected.

  Here, the ECU is equipped with a microcomputer, an element, and the like, and has functions for detecting the voltage, current, temperature, etc. of the unit cells 11 and controlling charge / discharge of each unit cell 11. It has a known configuration.

  The extension piece 36 extends along the longitudinal direction of the FPC main body 31 and has a rectangular shape shorter than the introduction piece 33. The extending pieces 36 are alternately extended from the two end portions in the width direction of the FPC main body 31 to positions shifted in the longitudinal direction. The extension piece 36 is placed on the extension piece placement portion 16 </ b> B of the substrate placement portion 16.

  The extension piece 36 is formed with an introduction line portion 37 extending from one end of the detection conductive path 32 </ b> B to the end portion of the extension piece 36. The extension piece 36 has an end portion of the introduction line portion 37. Is mounted with a voltage detection terminal section 38.

  The voltage detection terminal portion 38 of the extension piece 36 is electrically connected by being sandwiched between the auxiliary spring portions 26 attached to the positive electrode terminal 20A. For example, an ECU or the like is connected to the other terminal of the detection conductive path 32B. Information about the voltage obtained at the voltage detection terminal section 38 is taken into an ECU (not shown) through the lead-in section 37 and the conductive path 32, and the voltage of each unit cell 11 is detected.

Next, a method for assembling the battery module M will be described.
First, the unit cell group 10 and the FPC 30 are produced. The conductive path 32, the voltage detection terminal portion 38, the thermistor 35, electronic components, and the like are mounted and connected to the FPC 30 having a predetermined shape in which the plurality of extending pieces 36 and the introducing pieces 33 are formed, and the FPC 30 of this embodiment is manufactured.

  Next, a method for manufacturing the unit cell group 10 will be described. The unit cell group 10 uses a total of 24 two types of unit cells 11 (11A, 11B), and is arranged side by side on the same plane with the polarities of the electrode terminals 20A, 20B being alternately reversed. At this time, the separator 17 is disposed between the adjacent unit cells 11A and 11B so that the electrode terminal 20A of the unit cell 11A and the electrode terminal 20B of the unit cell 11B face each other.

  Next, when the unit cells 11A and the unit cells 11B are brought close to the arrangement direction of the unit cells 11, the flat surface portion 22B of the negative electrode terminal 20B and the insertion port 25B of the positive electrode terminal 20A are arranged to face each other, and the flat surface portion 22B. Is guided by the operation portion 23 of the electrode terminal 20A and is guided into the insertion port 25B.

  Further, when the unit cell 11A and the unit cell 11B are brought close to each other and the flat surface portion 22B is inserted into the insertion port 32, the spring member 24 is elastically restored, and the flat surface portion 22B of the negative electrode terminal 20B and the flat surface portion 22A of the positive electrode terminal 20A are connected. It is pressed by the elastic force of the spring member 24 (see FIG. 3). Thereby, the flat surface portion 22B of the negative electrode terminal 20B is sandwiched between the clamping spring portions provided in the positive electrode terminal 20A, and the assembly of the pair of unit cells 11A and 11B is completed. When such operations are repeated and 24 unit cells 11 (11A, 11B) are sequentially assembled, assembly of the unit cell group 10 is completed, and each unit cell 11 is connected to be conductive.

  Next, the FPC 30 is assembled to the upper surface of the unit cell group 10 from above (see FIGS. 8 to 10). Specifically, the eighth cell 11A from the left and the ninth cell 11B from the left in FIG. 8 and the eighth cell 11B from the right and the ninth cell from the right in FIG. When the introduction piece 33 is introduced between the unit cells 11A, the introduction piece 33 is received in the introduction piece receiving hole 18 formed in the separator 17, and the attachment of the thermistor 35 is thereby completed.

  Next, when each extending piece 36 of the FPC 30 is inserted into the auxiliary insertion port 26B of the auxiliary spring part 26, the auxiliary spring part 26 is elastically deformed, the auxiliary insertion port 26B is opened, and the extending piece 36 of the FPC 30 is opened. Can be accepted. Further, when the extension piece 36 of the FPC 30 is inserted into the auxiliary insertion port 26B, the auxiliary spring portion 26 is elastically restored, and the extension piece 36 of the FPC 30 and the flat surface portion 22A of the positive electrode terminal 20A are caused by the elastic force of the spring member 24. It is pressed (see FIG. 4). As a result, the FPC 30 is sandwiched between the auxiliary spring portions 26 provided on the positive electrode terminal 20 </ b> A, and the voltage detection terminal portion 38 provided on the extension piece 36 and the unit cell 11 can be electrically connected. When all the extending pieces 36 of the FPC 30 are sandwiched between the auxiliary spring portions 26, the battery module M is completed.

The operation and effect of this embodiment will be described.
In the present embodiment, a main body portion 31 in which a conductive path 32A is formed, an introduction line portion 34 that is continuous from one end of the conduction path 32A, and an introduction piece 33 that includes a thermistor 35 that is mounted on the introduction line portion 34 are provided. The thermistor 35 can be attached simply by arranging the FPC 30 in the unit cell group 10 and introducing the introduction piece 33 between the adjacent unit cells 11. Therefore, according to this embodiment, the attachment work of the thermistor 35 can be simplified.

  Moreover, according to this embodiment, since the thermistor 35 is a chip type, component cost can be reduced rather than the case where the temperature sensor connected with a lead wire is provided.

  Further, according to the present embodiment, the separator 17 disposed between the adjacent single cells 11 is provided, and the separator 17 is provided with the introduction piece receiving hole 18 capable of receiving the introduction piece 33 of the FPC 30. When the case 12 of the unit cell 11 is made of metal and a short circuit may occur due to contact between the cases 12, the introduction piece 33 of the FPC 30 is held between the unit cells 11 while preventing the occurrence of a short circuit. Can do.

  Further, according to the present embodiment, the FPC 30 includes a voltage detection terminal unit 38 that detects the voltage of the unit cell 11, a detection conductive path 32 </ b> B that is connected to the voltage detection terminal unit 38 and constitutes a voltage detection circuit, Since the voltage detection terminal unit 38 is connected to the single battery 11, both the temperature control circuit and the voltage detection circuit can be assembled by attaching only one FPC 30. In addition to simplification, the number of parts can be reduced.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) Although the FPC 30 in which the chip type NTC thermistor 35 is mounted is shown in the above embodiment, a thermistor other than the chip type or a thermistor other than the NTC thermistor may be mounted.
(2) In the above embodiment, the separator 17 is arranged between the single cells 11, but the separator 17 may not be provided.
(3) Although the FPC 30 including the voltage detection circuit and the temperature control circuit is shown in the above embodiment, the FPC including only the temperature control circuit may be used.
(4) In the above embodiment, the unit cell 11 including the substrate platform 16 is shown. However, the unit cell 16 may not be provided.
(5) In the above embodiment, the unit cell 11 of the type in which the electrode terminals are directly connected to each other without using a connecting member such as a bus bar is shown. However, the unit cell having a bolt-shaped electrode terminal and connected by the bus bar. The mounting structure of the thermistor 35 of the present invention may be applied to a unit cell group including:
(6) In the above embodiment, the introduction piece receiving hole 18 for receiving the thermistor 35 is provided in the separator 17. However, the unit cell 11 may be provided with a recess for receiving the thermistor 25.

M ... battery module 10 ... single cell group 11 ... single cell 11A ... single cell 11B ... single cell 12 ... case 17 ... separator 18 ... introduction piece receiving hole 20 ... electrode terminal 20A ... positive electrode side electrode terminal (positive electrode terminal)
20B ... Electrode terminal on the negative electrode side (negative electrode terminal)
30 ... FPC (Flexible Printed Circuit Board)
31 ... FPC main unit (main unit)
32 ... Conductive path 32A ... (for temperature control circuit) Conductive path 32B ... Detection conductive path 33 ... Introduction piece 34 ... Introduction line section 35 ... Thermistor

Claims (4)

It is a thermistor mounting structure that is attached to a unit cell group formed by connecting a plurality of unit cells side by side,
In the unit cell group, a flexible printed circuit board having a main body formed with a conductive path arranged along the arrangement direction of the unit cells and extending in the arrangement direction of the unit cells is arranged,
The flexible printed circuit board includes an introduction line portion that is connected from one end of the conductive path and is introduced between the adjacent unit cells, and a thermistor mounted on the introduction line portion. Provided integrally with the main body,
The thermistor mounting structure, wherein the thermistor is attached to the unit cell group by inserting the introduction piece between the adjacent unit cells. The thermistor mounting structure according to claim 1, wherein the thermistor is a chip type. The separator provided between the said adjacent single cells is provided, The said separator is provided with the introduction piece receiving hole which can receive the said introduction piece of the said flexible printed circuit board. Item 3. The thermistor mounting structure according to Item 2. The flexible printed circuit board is provided with a voltage detection terminal portion that detects the voltage of the unit cell, and a detection conductive path that is connected to the voltage detection terminal portion and constitutes a voltage detection circuit,
The thermistor mounting structure according to any one of claims 1 to 3, wherein the voltage detection terminal portion is connected to the unit cell.

Images