Cell system

Abstract

To provide a cell system that can improve the battery abnormality detection performance of a battery with thermal fuse by stably exposing the thermal fuse to gas emitted from the battery, thereby making it easier to design the route for a wiring harness and perform wiring work.SOLUTION: A cell system 10 includes a battery 12 having an open section 14 through which internal gas is discharged when the internal pressure rises, an exhaust path 16 through which the gas discharged from the open section 14 is guided, a temperature fuse 18 provided at a gas-passing position in the exhaust path 16, an abnormality determination unit 20 for determining the presence or absence of an abnormality in the battery 12 based on a signal from the temperature fuse 18, and an attached body 22 in which the temperature fuse 18 is mounted at a position where the temperature fuse 18 faces the attached battery 12 downward in the vertical direction. A part of the exhaust path 16 passes through the attached body 22, and the temperature fuse 18 is attached to the attached body 22 in the exhaust path 16 passing through the attached body 22.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a battery system. [Background technology]

[0002] Patent Document 1 discloses a battery module including a plurality of batteries each having an opening for discharging internal gas when the internal pressure rises, and an exhaust path for directing the gas discharged from the plurality of openings to an opening. In this battery system, a temperature fuse, which is a non-returnable switching element that changes when the temperature reaches or exceeds a reference temperature, is disposed at a position where the gas discharged from the opening passes. A high temperature abnormality determination unit including the temperature fuse is capable of quickly detecting an abnormality in the battery accompanied by gas generation due to an internal short circuit or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2012 / 014449 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the battery system of Patent Document 1, the thermal fuse needs to be exposed to the gas discharged from the opening of the exhaust passage, but since the gas discharged from the opening spreads in all directions from the opening, the thermal fuse cannot be stably exposed to the exhaust gas, and there is a risk that the performance of the thermal fuse in detecting abnormalities in the battery may be reduced. Also, for example, when the thermal fuse is fixed to a wire harness arranged in the battery system, the thermal fuse needs to be positioned near the opening when the wire harness is arranged, which creates problems such as limitations on the route design of the wire harness and cumbersome wiring work.

[0005] Therefore, we disclose a battery system that can improve the battery abnormality detection performance of the temperature fuse by stably exposing the temperature fuse to gas emitted from the battery, thereby making it easier to design the wiring harness route and perform the wiring work. [Means for solving the problem]

[0006] The battery system disclosed herein comprises a battery having an open portion through which internal gas is discharged when internal pressure rises, an exhaust path through which the gas discharged from the open portion is guided, a temperature fuse provided at a position in the exhaust path through which the gas passes, an abnormality determination unit that determines the presence or absence of an abnormality in the battery based on a signal from the temperature fuse, and a mounting body to which the temperature fuse is attached and which is installed in a vertically upward position relative to the battery, wherein a portion of the exhaust path passes through the mounting body, and the temperature fuse is attached to the mounting body in the exhaust path which passes through the mounting body. Effect of the Invention

[0007] According to the battery system disclosed herein, the temperature fuse can be stably exposed to gas emitted from the battery, thereby improving the battery abnormality detection performance of the temperature fuse, and facilitating the route design and wiring work of the wire harness. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a battery system according to the first embodiment. [Diagram 2] FIG. 2 is a longitudinal sectional view showing a model of the II-II cross section of the battery system shown in FIG. [Diagram 3] FIG. 3 is a vertical cross-sectional view showing a model of a battery system according to the second embodiment, and corresponds to FIG. [Figure 4] FIG. 4 is a vertical cross-sectional view showing a model of a battery system according to the third embodiment, and corresponds to FIG. [Diagram 5]5 is an enlarged longitudinal sectional view showing a main part taken along the line VV of FIG. [Figure 6] FIG. 6 is a perspective view showing a state in which a thermal fuse is inserted into a cylindrical portion protruding upward from a battery constituting the battery system shown in FIG. [Figure 7] FIG. 7 is an exploded vertical cross-sectional view of the battery system shown in FIG. [Figure 8] FIG. 8 is a vertical cross-sectional view showing a model of a battery system according to the fourth embodiment, and corresponds to FIG. [Figure 9] FIG. 9 is an exploded vertical cross-sectional view of the battery system shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] <Description of the embodiments of the present disclosure> First, embodiments of the present disclosure will be listed and described. The battery system of the present disclosure comprises: (1) A battery comprising an open portion through which internal gas is discharged when internal pressure rises, an exhaust path through which the gas discharged from the open portion is guided, a temperature fuse provided at a position in the exhaust path through which the gas passes, an abnormality determination unit which determines the presence or absence of an abnormality in the battery based on a signal from the temperature fuse, and a mounting body to which the temperature fuse is attached and which is installed in a vertically upward position relative to the battery, wherein a portion of the exhaust path passes through the mounting body, and the temperature fuse is attached to the mounting body in the exhaust path which passes through the mounting body.

[0010] According to this aspect, the thermal fuse is provided at a position in the exhaust path through which the gas discharged from the open part of the battery passes. This allows the thermal fuse to be stably exposed to the gas discharged from the battery, compared to a conventional structure in which the thermal fuse is provided outside the exhaust path. As a result, the thermal fuse can detect the gas temperature more accurately, and the performance of the thermal fuse in detecting abnormalities in the battery can be improved.

[0011] In addition, part of the exhaust path through which exhaust gas from the battery is guided is provided through a part of the mounting body that is installed in a position vertically upward relative to the battery, and the thermal fuse attached to the mounting body is disposed in the exhaust path that passes through the mounting body. This makes it unnecessary to align the thermal fuse with the exhaust path when wiring the wire harness, as compared to when the thermal fuse is fixed to the wire harness that is wired to the battery system, and makes it easier to design the path and wire the wire harness.

[0012] Here, the object to which the thermal fuse is attached may be anything that is installed in a vertically upward position relative to the battery, and may be a circuit structure equipped with a printed circuit board such as an ECU (Electronic Control Unit), or a component such as a lid that covers a housing that contains the battery.

[0013] The exhaust path may have any structure as long as it constitutes a path for guiding the gas discharged from the opening toward the thermal fuse. For example, the exhaust path may be provided by interconnecting through holes provided in a member including the mounting body interposed between the opening of the battery and the thermal fuse, or by providing a chimney-shaped tube in the housing that houses the battery and passing the chimney-shaped tube through the inner periphery of the through hole that penetrates the mounting body.

[0014] Note that "vertically facing upward" refers to the state in which the battery system is installed in an object (for example, a vehicle).

[0015] (2) In the above item (1), it is preferable that the cross-sectional area of ​​the exhaust path when cut by a virtual plane having the axis of the exhaust path as a normal line is smaller at the end on the thermal fuse side than at the end on the battery side.

[0016] The exhaust path is a path for guiding gas discharged from the open part of the battery, and is provided penetrating from the open part of the battery through the mounting body that is placed in a position facing vertically upward with respect to the battery. The thermal fuse is disposed at a portion of the exhaust path that passes through the mounting body. The cross-sectional area of ​​the exhaust path in a virtual plane with the axis of the exhaust path as a normal line is made smaller at the end on the thermal fuse side than at the end on the battery side. This allows gas discharged vertically upward from the open part of the battery in the event of a battery abnormality to be concentrated toward the thermal fuse, and the thermal fuse can be exposed to high-temperature exhaust gas more stably, thereby further improving the battery abnormality detection performance of the battery system.

[0017] The axis is a line passing through the centroid of the cylinder in the axial direction when the surfaces constituting the exhaust passage are considered as a cylinder. The cross-sectional area is the area of ​​the part enclosed by the lines that appear on an imaginary plane when the exhaust passage is cut on the imaginary plane with the axis as the normal line when the surfaces constituting the exhaust passage are considered as a cylinder.

[0018] (3) In the above (2), it is preferable that the cross-sectional area is smallest at the end on the thermal fuse side and largest at the end on the battery side. The cross-sectional area of ​​the exhaust path extending from the open part of the battery through the mounting body installed vertically above the battery is smallest at the end on the thermal fuse side and largest at the end on the battery side, and the cross-sectional area is neither largest nor smallest in the intermediate portion between the two ends. With this structure, the gas discharged vertically upward from the open part of the battery toward the thermal fuse can be more reliably concentrated toward the thermal fuse, and the thermal fuse can be more stably exposed to the exhaust gas.

[0019] (4) In the above (2) or (3), when the imaginary plane at the end on the battery side is defined as the battery side end imaginary plane and the imaginary plane at the end on the thermal fuse side is defined as the thermal fuse side end imaginary plane, the battery side end imaginary plane and the thermal fuse side end imaginary plane preferably intersect at an angle of 80 degrees to 100 degrees. By arranging the imaginary plane of the thermal fuse side end of the exhaust path to intersect with the imaginary plane of the battery side end of the exhaust path at an angle of 80 degrees to 100 degrees, the gas passing through the exhaust path can be exhausted from the end on the thermal fuse side toward the side of the battery, vertically above the battery. This can advantageously accommodate cases where exhausting gas toward the side of the battery is desired due to the arrangement of each device in the battery system.

[0020] (5) In any one of the above (1) to (4), it is preferable that the abnormality determination unit is provided on the mounting body. Since the abnormality determination unit is also provided on the mounting body to which the thermal fuse is attached, it is possible to shorten the path for transmitting a signal from the thermal fuse to the abnormality determination unit, thereby making it possible to reduce the weight of the battery system.

[0021] <Details of the embodiment of the present disclosure> Specific examples of the battery system of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0022] <Embodiment 1> Hereinafter, the battery system 10 according to the first embodiment of the present disclosure will be described with reference to FIGS. 1 and 2. The battery system 10 is mounted on, for example, an electric vehicle or a hybrid vehicle, and detects an abnormality when an abnormality occurs in the battery 12 installed in these vehicles. The battery system 10 is assembled to the vehicle in a direction in which the upper side in FIG. 2 faces upward in the vertical direction and the lower side in FIG. 2 faces downward in the vertical direction. The left-right direction and the front-rear direction of the battery system 10 when assembled to the vehicle are not limited, but in the following, the left side refers to the left side in FIG. 2, the right side refers to the right side in FIG. 2, the front side refers to the front direction in the direction perpendicular to the paper surface in FIG. 2, and the rear side refers to the back direction in the direction perpendicular to the paper surface in FIG. 2. In addition, for multiple identical members, only some of the members may be labeled, and the other members may be omitted. Each drawing shows the battery systems 10, 60, 80, and 130 as a model, and the thickness dimensions of each member may be exaggerated for ease of understanding.

[0023] <Battery System 10> The battery system 10 comprises a plurality of batteries 12 each having an opening 14 through which internal gas is discharged when internal pressure rises, an exhaust path 16 through which the gas discharged from each opening 14 is guided, and a thermal fuse 18 provided at a position in the exhaust path 16 through which the gas passes. The battery system 10 also comprises an abnormality determination unit 20 that determines the presence or absence of an abnormality in the batteries 12 based on a signal from the thermal fuse 18, and an ECU 22 as an attachment body to which the thermal fuse 18 is attached, which is disposed in a position facing vertically upward relative to the batteries 12.

[0024] <Battery 12> The battery 12 has a known structure, also called a single cell or a unit cell, and has an opening 14 for releasing gas to the outside of the battery when the pressure inside the battery rises due to an internal short circuit or the like. The battery 12 is generally rectangular box-shaped and is filled with an electrolyte or the like. In the first embodiment, for example, a lithium ion secondary battery or the like can be used, but various secondary batteries or primary batteries can be used. Since the battery 12 can have a known structure, a detailed description of the internal structure is omitted. The battery 12 is provided with positive and negative electrodes (not shown) that protrude upward. A plurality of the batteries 12 are arranged, for example, in the front-rear direction to form a battery group.

[0025] A busbar module 28 is provided above the battery group, and the positive and negative electrodes protruding upward from each battery 12 are connected by the busbar module 28. The batteries 12 may be electrically connected in series or in parallel by the busbar module 28. Since a known structure is also adopted for the busbar module 28, detailed description is omitted, but for example, one or more busbars are arranged on a base member made of synthetic resin, and the multiple busbar modules 28 are arranged side by side in the front-to-rear direction. The positive and negative electrodes of each battery 12 are connected by the busbars on the busbar module 28.

[0026] The battery group (plurality of batteries 12) connected in this manner by the busbar module 28 is housed in a housing 26. The housing 26 is hollow overall, and is composed of, for example, a housing body 30 that opens upward, and a lid 32 that covers the upper opening of the housing body 30. The material of the housing 26 is not limited, and it may be made of, for example, metal or synthetic resin, but in the first embodiment, it is made of metal. The housing 26 is long in the front-rear direction so that it can house the battery group. After the battery group is housed in the housing body 30, the housing body 30 and the lid 32 are overlapped with each other and fixed by bolts or the like.

[0027] <Open section 14> The battery 12 has an opening 14, and in the first embodiment, the opening 14 is open on the upper end surface of the battery 12. The busbar module 28 is configured to include a first through hole 34 that penetrates in the vertical direction. The housing 26 has a second through hole 36 that penetrates the lid 32 in the vertical direction, and when the battery 12 is housed in the housing 26, the opening 14, the first through hole 34, and the second through hole 36 communicate with each other in the vertical direction. The shapes of the first and second through holes 34, 36 are not limited, but are each, for example, a circular through hole, and in the first embodiment, the first and second through holes 34, 36 are formed to be approximately the same size.

[0028] <Attachment object (ECU22)> In the first embodiment, the ECU 22 is installed above the housing 26 as an attachment object. The ECU 22 is for controlling, for example, the battery 12, and a circuit body including a printed circuit board 40 and the like is housed inside a hollow case 38. In the first embodiment, the case 38 is configured to include an upper case 42 and a lower case 44, and the case 38 is made of, for example, synthetic resin. That is, the printed circuit board 40 is housed in the lower case 44 that opens upward, and the upper opening of the lower case 44 is covered by the upper case 42 to form the ECU 22. The printed circuit board 40 has an electric circuit (not shown) printed on one or both surfaces in the plate thickness direction (vertical direction in the first embodiment) of a base plate part made of, for example, synthetic resin. The electric circuit in the printed circuit board 40 may be electrically connected to the busbar module 28 by, for example, an electric wire (not shown). In addition, a microcomputer (not shown) constituting the abnormality determination unit 20 described later, a temperature sensor, and the like may be mounted on the printed circuit board 40.

[0029] <Exhaust Channel 16> In the first embodiment, the ventilation path 45 is provided penetrating the ECU 22, which is the mounting body, and the exhaust path 16 is formed by the ventilation path 45 and the first and second through holes 34, 36. That is, a part of the exhaust path 16 (the ventilation path 45) passes through the ECU 22, which is the mounting body. In particular, in the first embodiment, the exhaust path 16 extends straight in the vertical direction. That is, the ventilation path 45 is configured to include a third through hole 46 that penetrates the lower case 44 in the vertical direction, a fourth through hole 48 that penetrates the printed circuit board 40 in the vertical direction, and a fifth through hole 50 that penetrates the upper case 42 in the vertical direction. The ventilation path 45 is formed at a position that communicates with the first and second through holes 34, 36 in the vertical direction when the ECU 22 is fixed on the housing 26.

[0030] In the first embodiment, the first to fifth through holes 34, 36, 46, 48, and 50 constituting the exhaust passage 16 are each circular through holes and are formed to be approximately the same size. The ECU 22 can be fixed to the upper surface of the housing 26 by a known method such as adhesion or welding.

[0031] <Thermal fuse 18> A known thermal fuse may be used as the thermal fuse 18, which melts when the temperature acting on the thermal fuse body 52 exceeds a certain value. The temperature at which the thermal fuse 18 melts may be set arbitrarily, but may be set, for example, so that the thermal fuse 18 melts when gas at 100° C. is sprayed onto the thermal fuse body 52. ​​Lead wires 54, 54 extend from both end faces of the thermal fuse body 52 in the longitudinal direction.

[0032] The thermal fuse 18 thus constructed is disposed in a direction extending in the left-right direction in a fourth through hole 48 provided in the printed circuit board 40 of the ECU 22. In the first embodiment, each lead wire 54 extending from the thermal fuse 18 is overlapped with an electric circuit formed on the lower surface of the printed circuit board 40 and electrically connected by solder or the like. As a result, the thermal fuse 18 electrically connects the electric circuits on both sides of the fourth through hole 48 via each lead wire 54, and when, for example, high-temperature gas is sprayed to melt the thermal fuse 18, the electric circuits on both sides of the fourth through hole 48 are electrically disconnected. That is, the thermal fuse 18 is located in the fourth through hole 48 constituting the exhaust passage 16 passing through the mounting body (ECU 22), and is mounted on the printed circuit board 40 constituting the mounting body (ECU 22).

[0033] <Abnormality determination section 20> In the first embodiment, when an abnormality occurs in the battery 12 and the internal pressure rises, the gas inside the battery 12 is discharged and the thermal fuse 18 is melted. This causes the electrical circuit on the printed circuit board 40 to be disconnected, and the disconnection of the electrical circuit is detected, for example, by a microcomputer mounted on the printed circuit board 40, which detects changes in voltage, current, etc., and transmits a signal generated in response to the detection of the disconnection of the circuit to the outside of the battery system 10. Note that when the battery 12 is normal and the thermal fuse 18 is not melted, the microcomputer may transmit a signal to the outside indicating that the battery is normal, or may not transmit a signal when the battery is normal and transmit a signal to the outside when an abnormality occurs in the battery.

[0034] Therefore, the abnormality determination unit 20 that determines the presence or absence of an abnormality in the battery 12 based on a signal from the thermal fuse 18 (for example, a signal generated by disconnecting an electric circuit) is configured to include the printed circuit board 40. Therefore, in the first embodiment, the abnormality determination unit 20 is provided in the ECU 22, which is the body to which it is attached.

[0035] <Assembly of Battery System 10> The following describes a specific example of a method for assembling the battery system 10. Note that the method for assembling the battery system 10 is not limited to the embodiment described below.

[0036] First, a plurality of batteries 12 are prepared. The plurality of batteries 12 are arranged in the front-rear direction to form a battery group, and the positive and negative electrodes protruding upward from each battery 12 are connected by a bus bar module 28. This battery group and bus bar module 28 are housed in a housing body 30, and the upper opening of the housing body 30 is closed with a lid body 32, and the housing body 30 and the lid body 32 are fixed together.

[0037] Furthermore, the thermal fuse 18 is disposed inside the fourth through hole 48 in the printed circuit board 40, and each lead wire 54 of the thermal fuse 18 is fixed by soldering or the like to the electric circuit on the underside of the printed circuit board 40. The printed circuit board 40 with the thermal fuse 18 thus provided is housed in the lower case 44, and the upper case 42 is assembled and fixed to the lower case 44 from above. This completes the ECU 22 as the mounting body.

[0038] Then, the mounting object (ECU 22) is placed at a vertically upward position of housing 26 and fixed by adhesive or the like. At this time, housing 26 and ECU 22 are aligned so that first and second through holes 34, 36 and ventilation passage 45 (third to fifth through holes 46, 48, 50) communicate with each other in the vertical direction. As a result, battery system 10 is completed.

[0039] According to the battery system 10 of the first embodiment having the above-mentioned structure, when an abnormality such as an internal short circuit occurs in the battery 12, the internal pressure increases, and the electrolyte sealed inside the battery 12 may turn into gas and be ejected. This gas is discharged to the outside through the exhaust path 16 communicating with the open part 14. The thermal fuse 18 is provided inside the exhaust path 16. Here, the gas ejected from the battery 12 is high in temperature, and is ejected to the thermal fuse 18, the melting temperature of which is set to 100°C, for example, to melt the thermal fuse 18. A signal accompanying the melting of the thermal fuse 18 is detected (or determined) by a microcomputer or the like (anomaly determination unit 20) mounted on the printed circuit board 40, for example, and a signal indicating that the thermal fuse 18 has been melted is transmitted to the outside. When this signal is received, light, sound, a message, or the like is emitted, so that the user (for example, the driver of the vehicle) can grasp the melting of the thermal fuse 18, that is, the abnormality of the battery 12.

[0040] In particular, in the first embodiment, the exhaust path 16 extends in a substantially straight line, and the gas ejected from the battery 12 can be sprayed onto the thermal fuse 18 while relatively suppressing a drop in temperature. As a result, the thermal fuse 18 melts stably, and abnormalities in the battery 12 can be detected more reliably. Also, in the conventional structure, the thermal fuse is provided in the wire harness, which may limit the wiring path of the wire harness and reduce the efficiency of the wiring work, but by providing the thermal fuse 18 in the mounting body (ECU 22), the wiring harness path design and wiring work can be easily performed.

[0041] The abnormality determination unit 20 is provided in the mounting body (ECU 22). The abnormality determination unit 20 includes, for example, a microcomputer mounted on a printed circuit board 40 constituting the ECU 22. By configuring the abnormality determination unit 20 in this manner, it is possible to provide the abnormality determination unit 20 relatively close to the thermal fuse 18, and thus to quickly detect the meltdown of the thermal fuse 18, enabling the user to grasp an abnormality in the battery 12 at an earlier stage.

[0042] <Embodiment 2> A battery system 60 according to a second embodiment of the present disclosure will be described below with reference to Fig. 3. In the first embodiment, the first to fifth through holes 34, 36, 46, 48, 50 constituting the exhaust passage 16 are formed to be substantially the same size and extend straight in the vertical direction, but in the second embodiment, a different aspect is adopted in this respect. Below, differences from the first embodiment will be described, and detailed descriptions of members and parts that are substantially the same as those in the first embodiment will be omitted by assigning the same reference numerals in the drawings as those in the first embodiment.

[0043] In the second embodiment as well, the first through hole 62 in the busbar module 28 is connected to the open portion 14 in the battery 12, and the second through hole 64 is provided in the lid 32. A third through hole 68 is provided in the lower case 44, a fourth through hole 70 is provided in the printed circuit board 40, and a fifth through hole 72 is provided in the upper case 42. The third to fifth through holes 68, 70, 72 are connected in the vertical direction to form an air passage 73. The first and second through holes 62, 64 and the air passage 73 form an exhaust passage 74.

[0044] Here, in the second embodiment, the first to fifth through holes 62, 64, 68, 70, 72 are different in size. Specifically, the inner diameter of each of the first to fifth through holes 62, 64, 68, 70, 72 is gradually reduced toward the top. In other words, when the exhaust passage 74 is cut by imaginary planes P1 to P5 with the axis L of the exhaust passage 74 as a normal line (perpendicular line), the cross-sectional area of ​​the end portion on the thermal fuse 18 side (the end portion on the upper end side, the fifth through hole 72) is smaller than the cross-sectional area of ​​the end portion on the battery 12 side (the lower end portion, the first through hole 62). These cross-sectional areas are smallest at the end portion on the thermal fuse 18 side (the fifth through hole 72) and largest at the end portion on the battery 12 side (the first through hole 62). Therefore, the cross-sectional areas of the second to fourth through holes 64, 68, 70 are set to be intermediate between the cross-sectional areas of the first through hole 62 and the fifth through hole 72. Note that imaginary planes P1 to P5 are imaginary planes that extend perpendicular to the axis L of the exhaust passage 74, and extend over the areas in which the bus bar module 28, the cover 32, the lower case 44, the printed circuit board 40, and the upper case 42 are disposed.

[0045] In the battery system 60 of the second embodiment constructed as described above, the thermal fuse 18 is attached to the ECU 22 in the exhaust path 74 that passes through the ECU 22, and so the same effects as those of the first embodiment can be achieved. In particular, in the second embodiment, since the exhaust path 74 is configured as described above, the gas exhausted from the battery 12 gradually becomes concentrated as it moves upward, preventing the gas from diffusing and suppressing a decrease in the gas temperature. As a result, the thermal fuse 18 is stably melted, and abnormalities in the battery 12 can be detected more reliably.

[0046] <Embodiment 3> A battery system 80 according to a third embodiment of the present disclosure will be described below with reference to Figures 4 to 7. In the first embodiment, the upper surface of the lid 32 in the housing 26 is flat and wide, and the ECU 22 is placed on the upper surface of the lid 32, but in the third embodiment, a cylindrical portion 88 that protrudes upward is provided on the upper surface of the lid 86 in the housing 84. Also, an ECU 90 as a mounting body mounted to the housing 84 is formed with an insertion recess 92 that opens downward and into which the cylindrical portion 88 is inserted.

[0047] In the third embodiment, similarly to the first embodiment, a busbar module 28 is attached to a battery group consisting of a plurality of batteries 12, and each battery 12 and the busbar module 28 are housed in a housing 84 consisting of a housing main body 30 and a lid body 86. A first through hole 34 penetrating in the vertical direction is formed in the busbar module 28. The lid body 86 is integrally formed with the above-mentioned tubular portion 88 at a position corresponding to the first through hole 34, and an inner hole of the tubular portion 88 is a second through hole 94 penetrating the lid body 86 in the vertical direction. In the third embodiment, the tubular portion 88 is cylindrical and has a peripheral wall portion 98 that is annular in plan view and continues in the circumferential direction.

[0048] The thermal fuse 18 is provided at the upper end of the cylindrical portion 88. Specifically, as shown in Figs. 4 and 6, a pair of slits 100, 100 facing each other in the radial direction (left-right direction in the third embodiment) is provided at the upper end of the peripheral wall portion 98. Each slit 100 is a notch that opens upward and penetrates the peripheral wall portion 98 in the thickness direction. As shown in Fig. 5, a pair of inner peripheral protrusions 102, 102 protruding to the inner periphery are provided on both sides of the inner periphery surface of the peripheral wall portion 98 in a direction perpendicular to the opposing direction of the pair of slits 100, 100 (front-rear direction in the third embodiment). Each inner peripheral protrusion 102 is provided extending downward from a position spaced downward by a predetermined distance from the upper end of the peripheral wall portion 98, and the upper end surface of each inner peripheral protrusion 102 is an inclined surface 104 that gradually inclines downward toward the inner periphery.

[0049] The thermal fuse 18 is disposed on the inner periphery side of the cylindrical portion 88 having such a shape. Specifically, the radial width dimension (left-right width dimension) of the portion of the second through hole 94 where the inner peripheral protrusions 102 are not provided is made larger than the length dimension of the thermal fuse body 52 of the thermal fuse 18. In addition, the radial width dimension (front-rear width dimension) of the portion of the second through hole 94 where the inner peripheral protrusions 102 are provided is made smaller than the outer diameter dimension of the thermal fuse body 52. ​​As a result, as shown in Figs. 4 to 6, the thermal fuse 18 is disposed on the inner periphery side of the cylindrical portion 88, and the lead wires 54 protruding from the thermal fuse body 52 are inserted into the slits 100 provided at the upper end of the peripheral wall portion 98. In addition, the thermal fuse body 52 abuts against the inclined surfaces 104, which are the upper end surfaces of the inner peripheral protrusions 102, to prevent the thermal fuse 18 from falling out downward.

[0050] <Mounting body (ECU90)> Similarly to the first embodiment, the ECU 90 is configured by housing a printed circuit board 112 in a case 110 consisting of an upper case 106 and a lower case 108. A third through hole 114 is provided in the lower case 108, a fourth through hole 116 is provided in the printed circuit board 112, and a fifth through hole 118 is provided in the upper case 106. The third to fifth through holes 114, 116, and 118 communicate with each other in the vertical direction to form an air passage 119, and the air passage 119 and the first and second through holes 34, 94 form an exhaust passage 120. As described later, the cylindrical portion 88 is inserted through the third and fourth through holes 114, 116, so that the exhaust passage 120 is substantially formed by the first and second through holes 34, 94 and the fifth through hole 118 (particularly the upper portion). Therefore, in the third embodiment, a part of the exhaust passage 120 (for example, an upper part of the fifth through hole 118) passes through the ECU 90, which is the mounting body. Also, the upper case 106 is provided with a cylindrical insertion tube portion 122 that protrudes downward, and the fifth through hole 118 is formed including the inner hole of the insertion tube portion 122. In the third embodiment, the insertion tube portion 122 has a cylindrical shape.

[0051] The inner diameter of the third through hole 114 is larger than the outer diameter of the cylindrical portion 88 provided in the cover 86. The inner diameter of the fifth through hole 118 is different in the vertical direction, and the inner diameter of the lower portion, the insertion cylindrical portion 122, is larger than the inner diameter of the upper portion. The upper and lower portions of the fifth through hole 118 are connected by a tapered surface 124 in which the inner diameter gradually decreases toward the upper side on the inner circumferential surface of the fifth through hole 118. In the third embodiment, the inner diameter of the upper portion of the fifth through hole 118 is approximately equal to the radial width of the second through hole 94 (the left-right width of the second through hole 94) in the portion where the inner peripheral protrusions 102 are not provided. The inner diameter of the lower portion of the fifth through hole 118 is larger than the outer diameter of the cylindrical portion 88 and approximately equal to the inner diameter of the third through hole 114. Furthermore, the inner diameter of the fourth through hole 116 is larger than the outer diameter of the insertion tube portion 122 in the upper case 106 .

[0052] The printed circuit board 112 is housed in the lower case 108 having such a structure, and the upper case 106 is placed on the lower case 108 from above to fix the upper case 106 and the lower case 108 together, thereby forming the ECU 90. Specifically, the upper case 106, the lower case 108, and the printed circuit board 112 are placed on top of each other in the vertical direction, so that the insertion tube portion 122 protruding downward from the upper case 106 is inserted into the fourth through hole 116, and the lower surface of the insertion tube portion 122 is placed on the peripheral portion of the third through hole 114 on the upper surface of the lower case 108. As a result, the third through hole 114 and the fifth through hole 118 are communicated in the vertical direction on the inner peripheral side of the fourth through hole 116 to form the ventilation path 119, and the insertion recess 92 into which the cylindrical portion 88 is inserted is formed by the third through hole 114 and the insertion tube portion 122.

[0053] Then, the ECU 90 is overlapped and fixed from above the housing 84, so that the cylindrical portion 88 is inserted into the insertion recess 92. That is, the cylindrical portion 88 is inserted into the inner circumferential sides of the third and fourth through holes 114, 116. As a result, the first, second and fifth through holes 34, 94, 118 are communicated in the up-down direction on the inner circumferential sides of the third and fourth through holes 114, 116 to form the exhaust passage 120. Note that the insertion of the cylindrical portion 88 into the insertion recess 92 is restricted, for example, by the upper end of the cylindrical portion 88 abutting against the tapered surface 124 or by the upper end face of the cover 86 other than the position where the cylindrical portion 88 is formed abutting against the lower end face of the ECU 90 (the lower end face of the lower case 108). In the third embodiment, the thermal fuse 18 is also arranged on the inner periphery of the fourth through hole 116 in the printed circuit board 112, and each lead wire 54 of the thermal fuse 18 is fixed to an electric circuit provided on the underside of the printed circuit board 112 by soldering or the like.

[0054] In the battery system 80 in the third embodiment having the above-mentioned structure, the thermal fuse 18 is attached to the printed circuit board 112 constituting the ECU 90 in the exhaust passage 120 passing through the mounting body (ECU 90), so that the same effect as in the first embodiment can be achieved. In particular, in the third embodiment, the cylindrical part 88 protruding upward from the housing 84 (lid 86) is inserted into the insertion recess 92 in the exhaust passage 120, so that gas that is ejected when an abnormality occurs in the battery 12 is exhausted from the cylindrical part 88 through the fifth through hole 118 to the outside space via a shorter path. And, since the thermal fuse 18 is provided on such a path, the gas is ejected to the thermal fuse 18 while still in a high temperature state, so that the melting of the thermal fuse 18 is achieved more reliably. Therefore, detection of an abnormality in the battery 12 can be realized with a higher degree of reliability.

[0055] Furthermore, since the cylindrical portion 88 is inserted into the fourth through hole 116, the high-temperature gas passing through the cylindrical portion 88 does not come into contact with any part of the printed circuit board 112 other than the thermal fuse 18, and the high-temperature gas is prevented from affecting the printed circuit board 112. In addition, for example, when a plurality of batteries 12 are provided in the front-rear direction, a plurality of cylindrical portions 88 may be provided in the front-rear direction on the cover 86 corresponding to the batteries 12, and in this case, a plurality of insertion recesses 92 are also provided in the front-rear direction on the top surface of the ECU 90. In such a case, when the ECU 90 is superimposed on the housing 84, the housing 84 and the ECU 90 can be aligned with each cylindrical portion 88 and each insertion recess 92, thereby improving assembly efficiency.

[0056] <Embodiment 4> A battery system 130 according to a fourth embodiment of the present disclosure will be described below with reference to Figures 8 and 9. In all of the first to third embodiments, the exhaust passages 16, 74, 120 extend in the vertical direction, and gas emitted from the battery 12 is discharged above the ECU 22, 90. In the fourth embodiment, however, the exhaust passage 132 opens to the side (left), and gas emitted from the battery 12 is discharged to the left of the ECU 134, which is the mounting body. In particular, in the fourth embodiment, the upper part of the fifth through hole 118 in the third embodiment opens to the left, not upward. Therefore, the following description will focus on the differences from the third embodiment, and the same reference numerals as those in the third embodiment will be used to denote the substantially same members and parts as those in the third embodiment, and detailed description thereof will be omitted.

[0057] That is, in the fourth embodiment, the fifth through hole 136 is bent leftward at the middle part in the length direction, and the axis L' of the exhaust passage 132 is also bent leftward at the middle part in the length direction. In short, assuming a virtual plane with the axis of the exhaust passage 132 as a normal line (perpendicular line), the virtual plane at the end (lower end) on the battery 12 side is the battery side end virtual plane P1', and the virtual plane at the end (left end) on the thermal fuse 18 side is the thermal fuse side end virtual plane P5', these virtual planes P1', P5' intersect at a predetermined angle α (see FIG. 8). This angle α is not limited as long as it is greater than 0 degrees and less than 180 degrees (when α=0,180, the virtual planes P1', P5' are parallel), but is preferably 80 degrees or more and 100 degrees or less, and is set to approximately 90 degrees in the fourth embodiment. Incidentally, imaginary planes P1' and P5' are imaginary planes that extend perpendicular to axis L' of exhaust passage 132 and extend over the areas where bus bar module 28 and upper case 106 are disposed at the left end portions thereof.

[0058] The battery system 130 of the fourth embodiment having the above-described structure has the same structure as the third embodiment except that the exhaust passage 132 opens to the side, and therefore can achieve the same effects as the third embodiment. In the fourth embodiment, the imaginary planes P1', P5' intersect at a predetermined angle α and the exhaust passage 132 opens to the side instead of upward, so that a separate member can be disposed above the battery system 130 without being affected by the high-temperature gas discharged from the battery 12.

[0059] <Modification> Although the first to fourth embodiments have been described above as specific examples of the present disclosure, the present disclosure is not limited to these specific descriptions. Modifications, improvements, etc., within the scope of achieving the object of the present disclosure, are included in the present disclosure. For example, the following modified examples of the embodiments are also included in the technical scope of the present disclosure.

[0060] (1) In the above embodiment, a battery group is formed by providing a plurality of batteries 12, but a single battery may be used. When a plurality of batteries are provided, one or more exhaust paths (first through holes) through which gas discharged from the open parts of the plurality of batteries is collected and guided may be provided in the busbar module, and one or more corresponding ventilation paths may be provided in the mounting body (e.g., ECU), or the busbar module may be provided with exhaust paths (first through holes) corresponding to the open parts of each battery, and the mounting body (e.g., ECU) may be provided with a plurality of ventilation paths corresponding to each exhaust path (first through hole).

[0061] (2) In the first embodiment, the battery 12 is housed in the housing 26, and the ECU 22 is attached to the upper part of the housing 26 as an attachment object, but the present invention is not limited to this embodiment. That is, the attachment object attached to the battery may be a cover of the housing, and in this case, the thermal fuse may be provided in the second through hole in the cover. Therefore, the ECU is not essential in the battery system according to the present disclosure. Note that even if the attachment object is a separate member from the housing and is attached to the upper part of the housing, the attachment object is not limited to the ECU, and may be any in-vehicle device.

[0062] (3) In the above embodiment, the thermal fuse 18 is attached to the printed circuit board 40 constituting the ECU 22, 90, and the thermal fuse body 52 is located in the fourth through hole 48 in the printed circuit board 40, but this is not limited to this embodiment. Also, in the above embodiment, the lead wires 54 extending from the thermal fuse body 52 are electrically connected to the electric circuit on the underside of the printed circuit board 40, but this is not limited to this embodiment. For example, the lead wires of the thermal fuse may be electrically connected to the electric circuit on the top side of the printed circuit board, and the thermal fuse body may be located in the upper case or the lower case.

[0063] (4) The specific structures of the housing and the mounting body (e.g., ECU 22, 90) are not limited. The housing may be composed of a bottom plate located below and a substantially box-shaped housing body provided above the bottom plate and opening downward, and the second through hole may be provided in the upper bottom wall of the housing body. In addition, the mounting body is not limited to a structure consisting of an upper case, a lower case, and a circuit configuration such as a printed circuit board, and when the housing that accommodates the battery is formed from a synthetic resin, the cover and the lower case of the housing may be integrally formed. Furthermore, each of the through holes (e.g., the first to fifth through holes 34, 36, 46, 48, 50 in the first embodiment) that constitute the exhaust path does not need to be circular, and various shapes such as polygonal shapes such as triangles and rectangles, and circular shapes such as ellipses and ovals can be adopted.

[0064] (5) In the above embodiment, the abnormality determination unit 20 includes a microcomputer mounted on the printed circuit board 40, 112, for example, but is not limited to this. The abnormality determination unit that determines the presence or absence of an abnormality in the battery may be provided outside the body to which it is attached (e.g., ECU 22, 90), for example, or the microcomputer constituting the abnormality determination unit may be provided outside the body to which it is attached and connected to an electric circuit on the printed circuit board by an electric wire, for example.

[0065] (6) In the above embodiment, an example of a battery system that uses a temperature fuse to determine whether or not there is an abnormality in the battery is shown, but the battery system of the present disclosure is not limited to this. That is, the battery system of the present disclosure can be realized using a non-returnable switch that operates at a certain temperature or higher, and the present disclosure can be realized by using a non-returnable switch that operates at a certain temperature or higher, for example, a non-returnable switch using a bimetal, in addition to the example temperature fuse. In short, the battery system of the present disclosure also includes the following battery systems. (Another aspect of the present disclosure) A battery system comprising: a battery having an open portion through which internal gas is discharged when internal pressure rises; an exhaust path through which the gas discharged from the open portion is guided; a non-returnable switch provided at a position in the exhaust path through which the gas passes; an abnormality determination unit that determines whether or not there is an abnormality in the battery based on a signal from the non-returnable switch; and a mounting body to which the non-returnable switch is attached, the mounting body being installed in a position facing upward vertically relative to the battery, wherein a portion of the exhaust path passes through the mounting body, and the non-returnable switch is attached to the mounting body in the exhaust path that passes through the mounting body. However, the switch is not limited to a non-reset type switch, and a reset type switch such as a thermistor may also be used.

[0066] (7) In the above embodiment, an example of the battery system of the present disclosure is shown, but the present disclosure can also be provided as a battery system component used in a battery system for solving the same problem. In short, the present disclosure also includes a battery system component described in the following further aspect. (Still another aspect of the present disclosure) A battery system component that is assembled to a battery having an open portion through which internal gas is discharged when internal pressure rises to form a battery system, the battery system component comprising: an exhaust path through which the gas discharged from the open portion of the battery is guided; a non-returnable switch provided at a position in the exhaust path through which the gas passes; an abnormality determination unit that determines the presence or absence of an abnormality in the battery based on a signal from the non-returnable switch; and a mounting body to which the non-returnable switch is attached, the mounting body being placed in a position facing upward in the vertical direction relative to the battery, wherein a portion of the exhaust path passes through the mounting body, and the non-returnable switch is attached to the mounting body in the exhaust path that passes through the mounting body. [Explanation of symbols]

[0067] 10 Battery system (embodiment 1) 12 batteries 14 Open area 16 Exhaust duct 18 Thermal fuse 20 Abnormality determination section 22 ECU (mounted object) 26 Case 28 Busbar module 30 Main unit 32 Lid 34 First through hole 36 Second through hole 38 cases 40 Printed Circuit Board 42 Upper Case 44 Lower Case 45 Ventilation Channel 46 Third Through Hole 48 4th Through Hole 50 5th Through Hole 52 Thermal fuse body 54 Lead Wire 60 Battery system (embodiment 2) 62 First through hole 64 Second Through Hole 68 Third Through Hole 70 4th Through Hole 72 5th Through Hole 73 Ventilation Channel 74 Exhaust duct 80 Battery system (embodiment 3) 84 Case 86 Lid 88 Cylindrical part 90 ECU (mounted object) 92 Insertion recess 94 Second Through Hole 98 Peripheral wall section 100 Slits 102 Inner peripheral protrusion 104 Slope 106 Upper Case 108 Lower Case 110 cases 112 Printed Circuit Board 114 3rd Through Hole 116 4th Through Hole 118 5th Through Hole 119 Ventilation Channel 120 Exhaust duct 122 Insertion tube part 124 Tapered surface 130 Battery system (embodiment 4) 132 Exhaust duct 134 ECU (mounted object) L,L' axis P1~P5 Virtual plane P1' Virtual plane at battery end P5' Thermal fuse end imaginary plane

Claims

1. A battery having an opening through which internal gas can be discharged when the internal pressure increases; an exhaust path through which the gas exhausted from the open portion is guided; a thermal fuse provided at a position in the exhaust path through which the gas passes; an abnormality determination unit that determines whether or not there is an abnormality in the battery based on a signal from the thermal fuse; a mounting body to which the thermal fuse is attached and which is disposed in a position facing upward in a vertical direction with respect to the battery, A portion of the exhaust passage passes through the mounting body, The thermal fuse is attached to the object to be attached at the exhaust path passing through the object to be attached. Battery system.

2. The cross-sectional area of ​​the exhaust passage when cut by a virtual plane having the axis of the exhaust passage as a normal line is the cross-sectional area at the end portion on the thermal fuse side is smaller than the cross-sectional area at the end portion on the battery side; The battery system according to claim 1 .

3. The cross-sectional area is The temperature is smallest at the end of the thermal fuse and largest at the end of the battery. The battery system according to claim 2 .

4. The imaginary plane at the end portion on the battery side is defined as a battery side end imaginary plane, When the imaginary plane at the end portion on the thermal fuse side is defined as a thermal fuse side end imaginary plane, the battery side end imaginary plane and the thermal fuse side end imaginary plane intersect at an angle of 80 degrees or more and 100 degrees or less; The battery system according to claim 2 or 3.

5. The abnormality determination unit is provided on the mounting body. The battery system according to claim 1 .

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