JP2017123280A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module in which a fuse is not broken even when a step between battery cells is generated and a wiring substrate is distorted. SOLUTION: A metal lead 20 having a plate-like portion 21 fixed between terminals of a plurality of adjacent battery cells 11 and a standing portion 23, and extending from an insertion hole into which the standing portion 23 of the metal lead 20 is inserted. The wiring board 50 has an existing wiring pattern and a fuse 61 provided on the wiring pattern. The standing portion 23 of the metal lead 20 is in contact with the lower surface of the wiring board 50 and the wiring board 50. A battery module in which a reinforcing portion 25 for supporting the wiring is provided, and at least a part of the fuse 61 is arranged above the position where the reinforcing portion 25 of the metal lead 20 supports the wiring board 50. [Selection diagram] Fig. 6

Description

  The present invention relates to a battery module that prevents a fuse from being broken and has a waterproof function.

  As an example of a battery module, a substrate may be disposed between a positive electrode and a negative electrode of a battery cell, and a protective element (fuse, diode) may be disposed on the substrate. For example, in patent document 1, a board | substrate is arrange | positioned on a battery cell and a battery monitoring circuit and a cell balance circuit are connected with a harness. In this example, the metal is exposed at the electrode portion of the fuse.

  However, in the above configuration, since the fuse is exposed, there is a risk of leakage between the fuse terminals during submergence and submergence.

  In order to eliminate the above-described exposed state of the fuse, it has been proposed to coat the fuse with a mold resin (Patent Document 2).

  In order to prevent the leakage of the fuse, it has been proposed to arrange the fuse in the vicinity of the battery terminal (Patent Document 3).

JP 2012-230963 A Japanese Patent Laid-Open No. 06-314538 JP 2014-093864 A

  However, when the fuse is disposed in the vicinity of the battery terminal, a step is generated between the battery cells, and the fuse may be broken when the wiring board is distorted.

  In view of the above circumstances, an object of the present invention is to provide a battery module in which the fuse is not broken even when a step between battery cells occurs and a wiring board is distorted.

  In order to solve the above problems, the present invention has the following means.

In one plan, a battery module includes a plurality of batteries arranged side by side, a metal lead having a plate-like portion fixed between terminals of adjacent batteries, and a standing portion standing up and down, and the metal An insertion hole into which the standing part of the lead is inserted is formed, and a wiring board provided with a wiring pattern extending from the insertion hole, and a fuse provided on the wiring pattern,
The upright portion of the metal lead is inserted and fixed in the insertion hole of the wiring board, and the metal lead and the wiring board are electrically and mechanically connected, and the metal lead The standing portion is provided with a reinforcing portion that contacts the lower surface of the wiring board and supports the wiring board,
At least a part of the fuse is disposed above a position where the reinforcing portion of the metal lead supports the wiring board.

  According to one aspect, in the battery module, even when the step between the battery cells occurs and the wiring board is distorted, the fuse does not break.

The schematic perspective view of the battery module of embodiment of this invention. The short side view of the battery module according to the first embodiment of the present invention. FIG. 2 is a cross-sectional top view of a wiring board or the like cut along a B surface in FIG. 1. The circuit diagram of the battery module of the 1st Embodiment of this invention. The expanded sectional view of the fuse of the 1st Embodiment of this invention. FIG. 2 is a longitudinal side view of a periphery of a lead viewed from an arrow C in FIG. 1. (A) is a cross-sectional top view of the wiring board etc. of the 2nd Embodiment of this invention, (B) is an enlarged view of D part of (A). The expanded sectional view of the fuse of the 3rd Embodiment of this invention.

  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.

  A battery module (storage module) that is an embodiment of the present invention will be described. The battery module 1 which concerns on several embodiment of this invention can be mounted in vehicles, such as a hybrid vehicle and an electric vehicle, for example, and is used as a power supply device which supplies electric power to a motor for driving | running | working.

  First, a schematic configuration of an example of the battery module 1 according to the present invention will be described. FIG. 1 is a perspective view showing a schematic configuration of an example of a battery module 1 according to an embodiment of the present invention. FIG. 2 is a side cross-sectional view of the battery module 1 according to the first embodiment of the present invention in the short-side direction (in the direction of arrow A).

  1 to 3 and 5 to 8, the X axis, the Y axis, and the Z axis are axes orthogonal to each other. In the present embodiment, the axis corresponding to the vertical direction is the Z axis. The relationship among the X axis, the Y axis, and the Z axis is the same as in FIG. 1 in the other drawings.

  As shown in FIG. 1, the battery module 1 includes a battery stack 10, a metal lead 20, a lead fastening portion 30, a smoke exhaust duct 40, a wiring board 50, a protection element portion 60, a voltage monitoring circuit (battery monitoring means) 70, a substrate. An inter-connector 80 and a support 90 are provided.

  Referring to FIG. 1, a battery stack 10 is an assembled battery in which, for example, a plurality of battery cells 11 are arranged (stacked) in one direction along the Y direction of FIG.

  The battery cell 11 has, for example, a rectangular parallelepiped shape whose longitudinal direction is the X direction in FIG. In the vicinity of both ends of the upper surface of the battery cell 11 in the longitudinal direction (X-axis direction), electrode terminals 12 and 13 as a pair of electrodes are provided so as to protrude. The pair of electrode terminals 12 and 13 are, for example, a positive electrode terminal and a negative electrode terminal of the battery cell 11.

  Moreover, in the battery stack 10, the adjacent battery cells 11 are arrange | positioned so that the position of the positive electrode terminal 12 and the negative electrode terminal 13 may become reverse direction, for example. 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. 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.

  Metal leads (bus bars) 20 are connected between the plurality of battery cells 11 arranged in the battery stack 10. Supports 90 are provided at both ends of the battery stack 10 in the Y-axis direction.

  The battery module 1 is provided with two wiring boards 50 each having a wiring pattern 51 (see FIG. 3). Since the two wiring boards 50 are common to all the battery cells 11, it is not necessary to connect a harness or the like for each battery cell 11, the assembly and wiring can be simplified, and the wiring boards are fixed. Space can be minimized.

  Referring to FIG. 2, an inter-board connector 80 is provided above the smoke exhaust duct 40, and the inter-board connector 80 connects two wiring boards 50. The board-to-board connector 80 may be connected to an ECU (Electrical Control Unit) board provided in the vehicle.

  A terminal on the wiring pattern 51 of the wiring substrate 50 and a voltage monitoring circuit 70 for monitoring the state of the battery cell 11 such as cell balance and overcurrent are connected via a monitoring line (harness) 72. By gathering the harness 72 that connects the wiring pattern 51 and the voltage monitoring circuit 70 to the board-to-board connector 80, the wiring board 50 can be attached and detached together with the board-to-board connector 80.

  Therefore, the number of parts related to wiring can be reduced.

  1 and 2, the two wiring boards 50 are provided in the upper part of the battery module 1 and in the vicinity of both ends of the battery module 1 in the short direction (longitudinal direction of the battery cell 11, X-axis direction). It has been. That is, the two wiring boards 50 are arranged avoiding the central portion in the short direction of the battery module 1.

  Therefore, the smoke exhaust duct 40 can be provided in the central portion in the short direction of the battery module 1 without causing interference with the wiring board 50. The smoke exhaust duct 40 collects the generated gas and exhausts it outside the battery module 1 when ignition or smoke occurs due to an abnormality inside the battery cell 11, and further the battery module 1 is mounted with the gas. It has a function to discharge outside the vehicle.

  As described above, since the wiring board 50 can be arranged avoiding the central portion of the battery module 1, there is an advantage that the wiring board 50 and the smoke exhaust duct 40 do not interfere with each other.

  Here, when a step is generated between the battery cells 11 and the wiring substrate 50 is distorted, there is a possibility that a load is applied to the fuse and breaks.

  Therefore, in order to solve the above problem, in the embodiment of the present invention, the fuse 61 and the metal lead 20 are arranged as follows.

  FIG. 3 is a cross-sectional top view of the wiring board 50 and the like cut along the plane B of FIG. 1, and FIG. 4 is a circuit diagram of the battery module 1 according to the embodiment of the present invention.

  As an example, the wiring board 50 is configured by laminating a wiring pattern 51 that is a metal layer such as copper, using a glass epoxy (glass epoxy) resin as a base material. An insertion hole 55 into which a part of the metal lead 20 is inserted is formed in the wiring board 50. In the wiring board 50, the wiring pattern 51 extends from the insertion hole 55.

  The metal lead 20 connects the battery cells 11 and is connected to the wiring pattern 51 in the wiring substrate 50. In the middle of the wiring pattern 51, a fuse 61 is connected in series as a protective element.

  The voltage monitoring circuit 70 includes a terminal unit 71, a protection circuit, an IC, and the like, and monitors the voltage of the battery cell 11 and / or the connected ECU.

  As can be seen from the top view of FIG. 3, the protection element portion 60 (fuse 61) is disposed in the vicinity of the substrate bonding portion (terminal) 24 fitted in the insertion hole 55. Therefore, even when an overcurrent occurs, the overcurrent does not flow through the harness that connects the voltage monitoring circuit 70 and the wiring pattern 51 to the voltage monitoring circuit 70.

  FIG. 5 is an enlarged cross-sectional view around the protection element portion 60. In the protection element portion 60, the fuse 61, its electrode (fuse electrode) 62, and the solder 65 that connects the fuse electrode 62 and the wiring pattern 51 are covered with a sealing resin 66 that prevents water from entering.

  Therefore, for example, when the battery module 1 having this configuration is mounted on a vehicle, leakage between terminals may occur in the voltage monitoring circuit 70, the terminal portion 71 of the voltage monitoring circuit 70, or the wiring pattern 51 due to salt water immersion. In that case, when a leak occurs in the ECU and an overcurrent flows, the fuse 61 is cut off to make it in an insulating state, thereby preventing the spread of fire.

  As shown in FIG. 5, in this configuration, the fuse 61 and the fuse electrode 62 are sealed with resin 66 (epoxy resin), so that water can be prevented from entering this portion. Furthermore, it is possible to prevent salt water or metal foreign matter from adhering between the fuse electrodes 62 and re-conducting the interrupted portion.

  Therefore, it becomes possible to protect the overcurrent of the voltage monitoring circuit 70 after salt water immersion with a simple configuration.

  FIG. 6 is a side view in the longitudinal direction (arrow C direction) around the metal lead 20 according to the first embodiment.

  The metal lead 20 connects the battery cells 11 and is connected to the wiring pattern 51 of the wiring board 50. The metal lead 20 includes a plate-like lead 21, a monitoring terminal portion 22, an upright portion 23, a substrate joint portion (insertion portion, cell terminal, battery terminal) 24, and a reinforcing portion 25.

  The plate-like lead (plate-like portion) 21 is provided so as to connect and fix the positive electrode terminal 12 and the negative electrode terminal 13 of the adjacent battery cells 11 in the plurality of battery cells 11 arranged in parallel. Yes. Here, the plate-like leads 21 are fastened to the respective battery cells 11 by the lead fastening portions 30.

  The monitoring terminal portion 22 is provided integrally with the plate-like lead 21. The standing portion 23 is bent (connected) substantially vertically from the monitoring terminal portion 22 and functions as a column supporting the wiring board 50 by standing up and down.

  The upper end portion of the standing portion 23 is connected to the wiring substrate 50 and functions as the substrate bonding portion 24 that is inserted into the hole 52 of the wiring substrate 50. Here, the metal lead 20 and the wiring substrate 50 are electrically connected by the standing portion 23 (substrate bonding portion 24) being inserted into (inserted into) the insertion hole 55 of the wiring substrate 50 and fixed. Connected mechanically and mechanically.

  In the present embodiment, the reinforcing portion 25 is provided so as to be in contact with the lower surface of the wiring substrate 50 at a part of the portion of the standing portion 23 of the metal lead 20 that is connected to the wiring substrate 50.

  The reinforcing portion 25 may be configured integrally with the lead (standing portion 23) or may be attached separately.

  In the present embodiment, the protection element unit 60 is provided as close as possible to the monitoring terminal unit 22 with reference to the top sectional view of FIG. Therefore, referring to FIG. 6, the fuse 61 in the protection element portion 60 is provided on the upper surface side of the wiring board 50 where the reinforcing portion 25 of the metal lead 20 is disposed below the wiring board 50.

  In general, the fuse substrate portion constituting the fuse 61 is often made of ceramics and is strong against compressive stress, but has a characteristic that it is particularly weak against tensile stress, and is easily cracked by tension.

  As described above, since the plate-like lead 21 fixes the battery cells 11 so as to connect the terminals 12 and 13 adjacent to each other, when the external stress is applied to the battery module 1, Due to the plate-like leads 21, the corresponding end portions in the X direction are not fixed, and the adjacent battery cells 11 may shift in the vertical direction, resulting in a difference in height between the adjacent battery cells 11.

  If there is a difference in height between the adjacent battery cells 11, due to this difference, if the wiring substrate 50 is fixed to the metal lead 20 so as to be connected to the battery cell 11, the wiring substrate 50 is distorted.

  Therefore, by attaching the reinforcing portion 25 to the metal lead 20 or integrally forming it, the stress on the fuse 61 and the sealing resin 66 caused by the distortion of the wiring board 50 caused by the difference in height between the battery cells 11 is suppressed. Yes (see FIG. 6). Specifically, since the compressive stress of the reinforced portion in the wiring board 50 is not changed and the stress in the tensile direction is suppressed with respect to the protective element portion 60 at least a part of which is disposed on the reinforcing portion 25, Breakage of the fuse 61 and the sealing resin 66 can be prevented.

<Second Embodiment>
FIG. 7A shows a cross-sectional top view of the wiring board 50A and the like of the second embodiment of the present invention, and FIG. 7B shows an enlarged view of a portion D in FIG. 7A.

  In the present embodiment, in the wiring substrate 50A, the wiring pattern 51 in the vicinity of the mounting of the protection element unit 60 is a wide part 52 that widens the width of the pattern.

  With this configuration, the wide portion 52 having a wide wiring width in the vicinity of the mounting of the protection element portion 60 has high rigidity, and the wiring width of the other portion (the normal wiring pattern 51) is relatively narrow (narrow), so that it is thin. The rigidity of the part becomes relatively weak.

  Here, when an external stress is applied, the tensile stress applied to the vicinity of the mounting of the protection element portion 60 (the wide portion 52) by positively distorting the portion (51) having a thin wiring width and weak rigidity. And compressive stress can be suppressed. Therefore, distortion in the vicinity of the mounting of the protection element portion 60 can be alleviated, stress on the fuse 61 and the sealing resin 66 can be reduced, and the fuse 61 and the sealing resin 66 can be prevented from being broken.

  Also in this embodiment, as in the first embodiment shown in FIG. 6, the reinforcing portion 25 can be provided on the metal lead 20 to further prevent the fuse 61 and the sealing resin 66 from being broken.

<Third Embodiment>
FIG. 8 is an enlarged cross-sectional view of the protection element portion 60B of the third embodiment.
In the present embodiment, a fuse element (fuse) 61B is arranged in a recess at the lower part of the protection element portion (fuse portion) 60B, and a fuse casing that covers the wiring pattern 51 that is a glass epoxy substrate (glass epoxy substrate) and the fuse element 61B. A wall is created by the body 63.

  In this configuration, since the sealing resin 66 does not directly adhere to the fuse element 61B, the thermal stress from the sealing resin 66 generated during the cooling / heating cycle is not applied to the fuse element 61B, and the breakage of the fuse element 61B can be suppressed.

  Also in this embodiment, as in the first embodiment shown in FIG. 6, the reinforcing portion 25 can be provided on the metal lead 20 to further prevent the fuse 61 and the sealing resin 66 from being broken.

  However, even if the fuse element 61B is blown out, it is possible to prevent a decrease in insulation due to subsequent carbonization of the sealing resin 66.

  Although the battery module has been described with a plurality of embodiments, the present invention is not limited to the above embodiments, and various modifications and improvements can be made within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Battery module 10 Battery stack 11 Battery cell 12 Positive electrode terminal 13 Negative electrode terminal 14 Separator 20 Metal lead (lead terminal, conducting wire)
21 Plate-shaped part (plate-shaped lead)
22 Monitoring terminal part 23 Standing part 24 Board | substrate junction part (battery terminal)
25 connecting portion 30 lead screw fastening portion 40 smoke exhaust duct 50, 50A wiring board 51 wiring pattern 53 lower wiring pattern 55 insertion hole 60, 60B protection element portion 61, 61B fuse (fuse element)
62 Fuse electrode 63 Fuse protector 65 Solder 66 Sealing resin 70 Voltage monitoring circuit 80 Board-to-board connector 90 Support (frame)

Claims (1)

A plurality of batteries arranged side by side;
A metal lead comprising a plate-like portion fixed between adjacent battery terminals and a standing portion standing up and down;
A wiring board in which an insertion hole into which the standing part of the metal lead is inserted is formed, and a wiring pattern extending from the insertion hole is provided, and
A fuse provided on the wiring pattern,
The standing portion of the metal lead is inserted and fixed in the insertion hole of the wiring board, and the metal lead and the wiring board are electrically and mechanically connected,
The standing part of the metal lead is provided with a reinforcing part that contacts the lower surface of the wiring board and supports the wiring board,
At least a part of the fuse is disposed above the position where the reinforcing portion of the metal lead supports the wiring board.
Battery module.

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