JP2012113896A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect cables furnished in a battery pack to acquire information on the status of plural batteries from heat, and to reduce the size of the battery pack and the number of components in it.SOLUTION: A battery pack 1 includes a safety valve 13 provided on a top face 11a of an exterior case and designed to rupture when the internal pressure of a battery cell becomes abnormal; a cover section 30 insulating between a bus bar 20 and an exterior case 11 and installed so as to cover the top face 11a part of the exterior case, except at least the safety valve 13; a smoke extraction duct 60 having a heat resistant property and installed, with its inner wall surface 60a opposed to the safety valve 13, so as to be exposed to a smoke extraction passage 61 which has the safety valve 13, not covered by the cover section 30, formed inside thereof; and a cable 70 composed of a bundle of plural voltage detection lines 72 extending from terminals 71 which are electrically connected to a plurality of battery cells 10 in order to acquire information on the status of the plurality of battery cells 10 and laid and wired above the smoke extraction duct 60.

Description

  The present invention relates to an assembled battery configured by electrically connecting a plurality of stacked battery cells.

  The assembled battery described in Patent Document 1 is formed by stacking and combining a plurality of thin rectangular parallelepiped battery cells, and connecting battery cell electrode terminals in series by a bus bar, and a safety valve is provided on the side surface of each battery cell. ing. This safety valve is formed by attaching a thin metal film to a hole opened on a side surface of a metal outer case of a battery cell. When the inside of the battery cell is in an abnormally high pressure state, the metal film is broken and degassed, whereby the nonaqueous electrolyte secondary battery itself can be prevented from bursting.

  Further, as a conventional assembled battery, unlike Patent Document 1, a battery having a safety valve provided near the center of the upper surface of the battery cell case, for example, at the center of the upper surface located between the positive electrode terminal and the negative electrode terminal is known. ing. The assembled battery having such a configuration includes a discharge duct that forms a passage for guiding and discharging the gas ejected from the safety valve. Therefore, the discharge duct extends over the entire length of the assembled battery in the stacking direction so as to cover the center of the upper surface of each battery cell that is stacked.

  In the case of this conventional battery pack, when the inside of the battery becomes an abnormally high pressure, the safety valve on the upper surface of the battery cell is broken and high temperature gas is ejected from the upper surface of the battery cell. Since a high-temperature gas flows through the passage inside the discharge duct when the safety valve breaks, the cable used to input information about the battery such as voltage and temperature to the control device or the like is covered with the cable. In order not to cause problems such as melting due to the heat of gas, wiring is performed as far as possible from the discharge duct. For example, the cable is provided so as to extend in parallel at a predetermined distance on both sides of the discharge duct extending at the center of the battery cell over the entire length in the stacking direction of the assembled battery.

JP 2003-346754 A

  However, in the conventional assembled battery in which the cable is arranged away from the discharge duct as described above, the space for mounting the cable is large, which is an adverse effect of reducing the size of the assembled battery. Further, when the cables are arranged on both sides of the discharge duct, there is a problem that the number of members for supporting and protecting the cables increases.

  Therefore, the present invention has been made in view of the above problems, and for an assembled battery including a cable for obtaining information on a plurality of battery states, the cable is protected from heat, and the size and number of parts are reduced. The purpose is to reduce.

The present invention employs the following technical means to achieve the above object. That is, according to the first aspect, a plurality of battery cells (10) each having an electrode terminal (12) including a positive electrode terminal and a negative electrode terminal projecting upward from the outer case (11) are stacked and adjacent to each other in the stacking direction (X). The battery cell (10) is an invention relating to an assembled battery (1) configured to be energized by connecting between the electrode terminals to be connected in a bus bar (20),
A safety valve (13) that is provided on the end surface (11a) of the outer case and breaks when the pressure inside the battery cell becomes equal to or higher than a predetermined pressure, and insulates between the bus bar (20) and the outer case (11) of the battery cell, A cover part (30) provided so as to cover at least the end face part of the outer case excluding the safety valve (13), and a heat-resistant duct part (60), and the safety valve not covered with the cover part (30) The duct part (60) in which the inner wall surface (60a) is provided facing the safety valve (13) so as to expose the passage (61) formed in (13), and information on the state of the plurality of battery cells. In order to obtain, a cable (70) formed by bundling a plurality of detection wires (72) extending from terminals (71) electrically connected to a plurality of battery cells, and placed above the duct portion (60). Wired Characterized in that it comprises a cable (70), the.

  According to this invention, even if high-temperature gas flows through the passage in the duct portion due to the breakage of the safety valve, the cable is placed and wired above the heat-resistant duct portion to protect the cable from heat. can do. The heat resistance of the duct portion means that the inside of the battery cell is in an abnormally high pressure state, and even if the gas inside the battery cell is ejected from a broken safety valve, the duct portion does not melt and does not break. Furthermore, since the cable is routed along the duct portion above the duct portion, the space for routing the cable can be reduced in size, and the members for wiring and supporting the cable can be reduced. Therefore, it is possible to provide an assembled battery that can protect the cable from heat, reduce the size, and reduce the number of components.

  According to claim 2, the cover part (30) is formed of a heat-resistant resin. According to this invention, since the cover portion is also heat-resistant by forming the cover portion with a heat-resistant resin, the temperature resistance performance around the duct portion against high-temperature gas can be improved. Therefore, the protection of the cable from heat can be improved.

  According to claim 3, the duct part (60) has higher heat resistance than the cover part (30). According to the present invention, by making the heat resistance of the duct portion higher than that of the cover portion, the duct portion that can be in direct contact with the high temperature gas is ensured in the temperature resistance performance, so that the cable is more reliably protected from the high temperature gas. Can be anything.

  According to claim 4, the duct part (60) is provided with a flange part (60b) that comes into close contact with the end surface (11a) of the outer case including the part where the safety valve (13) is provided. . According to the present invention, by increasing the degree of adhesion between the duct portion and the end surface of the cell outer case with the flange portion, it is possible to improve the barrier property of the passage in the duct portion with the outside, and to leak gas to the outside when the battery cell is abnormal Can be prevented.

  According to claim 5, the cable (70) is provided with the exterior tube (73) that insulates and encloses the conductor portions (72a) of the plurality of detection lines (72), and crosses the exterior tube (73). The surface shape is a flat shape whose length in the height direction is shorter than the length in the horizontal direction.

  According to this invention, since the length in the height direction of the cable can be suppressed by forming the outer tube that insulates and stores the plurality of electric wires in a flat shape, the overall height of the assembled battery can be suppressed. . In addition, since a plurality of electric wires for acquiring information related to a plurality of batteries are housed in a state of being bundled together by an outer tube, man-hours required for wiring can be further reduced.

  According to a sixth aspect of the present invention, the cable (70) wired above the duct portion (60) is further covered from above and includes a wiring protection member (80) for protecting from the outside. According to the present invention, the lower portion of the cable is protected by the duct portion, and the upper portion of the cable is protected from the outside by the wiring protection member. Therefore, even when an external load is applied during assembly work, maintenance, etc., the external force is directly applied to the cable. It is possible to prevent defects such as cracks and disconnections from occurring.

  The reference numerals in parentheses of the above means are an example showing the correspondence with the specific means described in the embodiments described later.

It is sectional drawing for demonstrating the arrangement configuration of the duct for flue gas and a voltage detection line in the assembled battery of 1st Embodiment to which this invention is applied. It is a top view for demonstrating the arrangement configuration of the smoke exhaust duct and a voltage detection line in the assembled battery of 1st Embodiment. It is the partially broken side view for demonstrating the arrangement configuration of the smoke exhaust duct and the voltage detection line in the assembled battery of 1st Embodiment. FIG. 4 is a partially enlarged cross-sectional view for explaining the arrangement of the smoke exhaust duct and the voltage detection line in the assembled battery of the first embodiment. It is the perspective view which expanded partially in order to demonstrate the structure regarding engagement of a cover part and a case in the assembled battery of 1st Embodiment.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not specified, unless there is a particular problem with the combination. Is also possible.

(First embodiment)
The assembled battery 1 according to the first embodiment to which the present invention is applied is also referred to as a battery pack, in which a plurality of battery cells 10 are arranged side by side so that their side surfaces face each other, and electrodes of different polarities of adjacent battery cells 10 are arranged. This is an assembly of battery cells 10 in which terminals are electrically connected in series by a bus bar 20 and integrated.

  The assembled battery 1 is used in, for example, a hybrid vehicle that uses a traveling drive source by combining an internal combustion engine and a motor driven by electric power charged in the battery, an electric vehicle that uses a motor as a travel drive source, and the like. The secondary battery constituting the assembled battery 1 is, for example, a nickel hydride secondary battery, a lithium ion battery, or an organic radical battery, and is a space between the rear seat and the trunk room under the seat of the automobile while being housed in the case. It is arranged in the space between the driver seat and the passenger seat.

  1st Embodiment which is one Embodiment of this invention is described using FIGS. FIG. 1 is a cross-sectional view for explaining the arrangement of the smoke exhaust duct 60 and the voltage detection line 72 in the assembled battery 1 of the first embodiment. However, the battery cell 10 is not shown in cross section. FIG. 2 is a plan view for explaining an arrangement configuration of the smoke exhaust duct 60 and the voltage detection line 72 in the assembled battery 1. FIG. 3 is a partially broken side view for explaining the arrangement configuration of the smoke exhaust duct 60 and the voltage detection line 72 in the assembled battery 1. FIG. 4 is a partially enlarged cross-sectional view for explaining the arrangement configuration of the smoke exhaust duct 60 and the voltage detection line 72 in the assembled battery 1. In each figure, a direction in which a plurality of battery cells 10 are stacked and arranged is defined as a cell stacking direction X, and each of the rectangular parallelepiped battery cells 10 is elongated in the horizontal direction and is orthogonal to the cell stacking direction X. Is Y, and the direction in which the electrode terminal 12 protrudes is the electrode terminal protruding direction Z or the upward direction Z.

  The assembled battery 1, which is an assembly of a plurality of battery cells 10, is controlled by electronic components (not shown) used for charging and discharging or temperature adjustment of the plurality of battery cells 10, and is blown by a blowing member (not shown). In response, each battery cell 10 is cooled. The assembled battery 1 is formed by electrically connecting a plurality of stacked battery cells 10 in series by a bus bar 20 and accommodated in a case 40. Moreover, the assembled battery 1 may have a structure in which each battery cell 10 is installed and supported so as not to move to a predetermined position in the case 40, or a compressive force is applied in the cell stacking direction X by a restraining means such as a band. A structure that is received and restrained and supported integrally may be used. The above electronic components are a DC / DC converter, a motor for driving a blowing member, an electronic component controlled by an inverter, various electronic control devices, and the like, and are adjusted by, for example, a power element that is a switching power supply device. It is a part operated by electric power.

  The case 40 has insulating properties, and is formed of a synthetic resin such as polypropylene (PP), a filler for improving strength, and PP containing talc. The case 40 is provided with an attachment portion for fixing the case 40 to the vehicle side by bolting or the like, and an equipment storage box (both not shown).

  The device box is configured to be communicable with a battery monitoring unit (not shown) to which detection results from various sensors for monitoring the state of the battery cell 10 such as voltage and temperature are input. A control device (not shown) for controlling power transmission / reception of the DC / DC converter and controlling driving of the motor of the blower member, a wire harness for connecting each device, and the like are housed.

  The battery monitoring unit is a battery ECU that monitors the state of each battery cell 10, and a plurality of terminals extending from a detection unit (terminal) installed on the battery cell 10 side in order to detect information related to the state of the plurality of battery cells 10. It is connected to the assembled battery 1 via the detection line. The detection line is, for example, a communication line for transmitting information such as the voltage and temperature of the battery cell 10 to the battery monitoring unit, and the terminal is a voltage measuring element and a temperature sensor for detecting information related to the state of the battery cell 10. And various other sensors.

  Each battery cell 10 constituting the laminate includes an outer case 11 constituting an outer shell such as an aluminum can, for example, and includes an electrode terminal 12 including a positive terminal and a negative terminal protruding upward from the upper surface 11a of the outer case. ing. The electrode terminals 12 which are terminals of different polarities and are connected between the adjacent battery cells 10 are connected by a bus bar 20 which is a metal plate having excellent electrical conductivity. The plurality of battery cells 10 constituting one stacked body are connected in series so as to be energized by the corresponding number of bus bars 20. In other words, all the battery cells 10 of the assembled battery 1 are electrically connected in series via the bus bars 20 so that the current flows in a zigzag shape or a meandering shape in plan view. Furthermore, each electrode terminal 12 arranged at both ends of the laminate that can be energized by the bus bar 20 is joined to the flat electrode plate 20A by welding in a state of being fitted into the terminal fitting openings 23A and 24A. . The electrode plates 20A arranged at both ends are connected to a total terminal portion where power is supplied and discharged.

  As shown in FIGS. 1 and 2, the bus bar 20 is a plate-like body having bus bar convex portions 22 formed so as to protrude outward on the center side. The bus bar 20 includes terminal connection portions 21 that extend laterally from the base of the bus bar convex portion 22 on both sides of the bus bar convex portion 22 in the cell stacking direction X. That is, the vertical cross-sectional shape of the bus bar 20 is a shape configured by an inverted U-shaped portion corresponding to the bus bar convex portion 22 and two horizontal portions extending left and right from the inverted U-shaped portion. The bus bar convex portion 22 is, for example, a convex portion such as a curved shape protruding outward in a U shape or a bent shape bent in a square shape such as a U shape.

  The terminal connecting portion 21 that is a horizontally extending portion has a first terminal fitting opening 23 formed on one end side with respect to the bus bar convex portion 22 and a second terminal fitting formed on the other end side. An opening 24 is formed. In the first terminal insertion opening 23 and the second terminal insertion opening 24, the electrode terminals 12 to be connected in the adjacent battery cells 10 are fitted on both sides of the bus bar protrusion 22. . That is, the shape of the first terminal insertion opening 23 and the second terminal insertion opening 24 is the same as the cross-sectional shape of the electrode terminal 12 and is sized to allow the electrode terminal 12 to be inserted.

  A safety valve 13 is provided on the upper surface 11 a of the outer case in each battery cell 10. The safety valve 13 is provided on the upper surface 11a of the outer case, and is set to be broken when the internal pressure of the battery cell 10 becomes an abnormal pressure. For example, the safety valve 13 is configured by sticking and closing a thin metal film in a hole opened in the upper surface 11a of the outer case of the battery cell 10. In this case, when the internal pressure of the battery cell 10 becomes an abnormal pressure, the metal film is broken and the hole opened in the upper surface 11a of the outer case is opened, and the inside of the battery cell 10 is opened. By releasing the gas to the outside of the cell, the internal pressure of the cell is lowered, and the battery cell itself can be prevented from bursting.

  The cover portion 30 is provided so as to insulate the bus bar 20 and the outer case 11 of the battery cell 10 and cover at least the upper surface 11 a portion of the outer case excluding the safety valve 13 and the electrode terminal 12. That is, an opening larger than the safety valve 13 is formed in the cover portion 30 at a position corresponding to the safety valve 13 when the cover portion 30 is mounted so as to cover the upper surface 11a of the outer case. Therefore, the safety valve 13 is exposed inside the opening 30 without being covered by the cover 30 when the cover 30 is attached.

  The assembled battery 1 further includes a smoke exhaust duct 60 provided so as to expose the safety valve 13 in the smoke exhaust passage 61 inside the duct. The smoke exhaust duct 60 is formed of a material having heat resistance. For example, the smoke exhaust duct 60 is formed of polyphenylene sulfide resin (PPS), polyethylene resin (PE), various resins to which a flame retardant is added, or the like. The heat resistance of the smoke exhaust duct 60 is such that even if the inside of the battery cell 10 is in an abnormally high pressure state and the internal gas is blown out by the break of the safety valve 13, the duct portion does not melt and is not damaged. It is.

  Further, the smoke exhaust duct 60 may be formed of a material having higher heat resistance than the cover part 30. In this case, for example, the exhaust duct 60 is made of polyphenylene sulfide resin (PPS), polyethylene resin (PE), various resins to which a flame retardant is added, and the cover portion 30 is made of polypropylene (PP resin). That's fine.

  The smoke exhaust duct 60 has a U-shaped cross section, and is provided so that an inner wall surface 60 a facing downward faces the safety valve 13. Further, the smoke exhaust duct 60 is a portion extending in the horizontal direction, and includes a flange portion 60b that comes into close contact with the upper surface 11a of the exterior case when the smoke exhaust duct 60 is installed on the upper surface 11a of the exterior case.

  The flange portion 60b corresponds to a contact portion between the smoke exhaust duct 60 and the upper surface 11a of the exterior case, and contributes to an improvement in air density at the contact portion. In order to increase the vessel density, the flange portion 60b may be formed of a softer material than other portions of the smoke exhaust duct 60. In this case, the smoke exhaust duct 60 is formed by two-color molding. Etc. can be produced. Moreover, you may provide a soft packing member in the lower surface of the flange part 60b.

  The smoke exhaust duct 60 having such a configuration is a discharge duct portion that forms a passage for guiding and discharging the gas ejected from the safety valve 13. Therefore, the smoke exhaust duct 60 covers the central portion of the upper surface of each battery cell 10 that is stacked, and is provided over the entire length of the assembled battery 1 in the cell stacking direction X. Therefore, when the safety valve 13 is broken when the inside of the battery cell 10 becomes an abnormally high pressure and high temperature gas is ejected from the upper surface of the battery cell 10, the smoke exhaust passage 61 covered with the smoke exhaust duct 60. Even if the high temperature gas flows, the high temperature gas can be prevented from touching members outside the smoke exhaust duct 60. Further, since the hot gas flows down the smoke passage 61 and is discharged to a place where there is no part that may cause a problem due to heat, the hot gas flows through a space isolated from the part.

  The cover 30 is a separate member from the smoke exhaust duct 60 and the case 40, and has at least an opening through which the electrode terminal 12 is inserted and an opening through which the safety valve 13 is exposed. This is a partly covering member. The cover part 30 has insulating properties, and is formed of, for example, a synthetic resin such as polypropylene (PP resin), PP resin containing filler or talc, and has a function of electrically insulating the bus bar 20 and the outer case 11. .

  Furthermore, it is preferable that the cover part 30 is formed with resin which has heat resistance. In this case, the cover portion 30 is formed of, for example, polypropylene (PP resin), polyphenylene sulfide resin (PPS), polyethylene resin (PE), various resins to which a flame retardant is added, or the like.

  The cover part 30 is provided with a plurality of claw parts 33 on the outer peripheral edge of which a fitting convex part 33a that protrudes outward is formed. The claw portion 33 is a free end whose root portion is fixed and whose tip is not fixed. When an external force is applied to the claw portion 33 inward, the claw portion 33 is directed outward to return to the original posture. It is designed to be elastically deformed. On the other hand, the case 40 to which the cover part 30 is attached includes an accommodating part 41 that can accommodate the claw part 33 inserted from above at a position corresponding to the claw part 33 on the outer peripheral edge thereof.

The accommodating part 41 is a cylindrical body whose upper end and lower end are open, and one side surface of the inner wall surface extending in the vertical direction is formed integrally with the case 40. FIG. 5 is a partially enlarged perspective view for explaining a configuration related to the engagement between the cover portion 30 and the case 40 in the assembled battery 1.
As shown in FIG. 5, when the cover portion 30 is attached to the case 40 from above so as to insert each claw portion 33 into the corresponding accommodating portion 41, the claw portion 33 is elastically deformed inward. It is displaced downward while contacting the inner wall surface of the accommodating portion 41. When the cover 30 is lowered to a position where it comes into contact with the upper surface 11a of the exterior case, the claw 33 is positioned at the lowest position, and the fitting convex portion 33a protrudes downward from the lower end opening of the housing portion 41. Then, the lock mechanism is formed by restoring so as to open outward and pressing the lower end surface of the accommodating portion 41. Since the claw portion 33 maintains this state, the cover portion 30 is fixed to the case 40.

  The assembled battery 1 has electrical insulating properties, and includes a positioning protrusion 31 that protrudes above the upper surface 11a of the outer case between the battery cells 10 adjacent to each other in the cell stacking direction X. The positioning convex portion 31 is formed of, for example, various types of resin having electrical insulation properties, and covers the upper surface 11a of the outer case so as to cover the upper opening of the case 40 and is attached to the cover portion 30 attached to the case 40. It is integrally formed. That is, the positioning convex portion 31 is a wall that rises upward in a portion that covers the upper part of the inter-cell passage 50 (battery fluid passage) formed between the adjacent battery cells 10. As shown in FIG. 2, the positioning protrusion 31 is thin in the cell stacking direction X and extends so as to be parallel to the inter-cell passage 50 in both the electrode terminal protruding direction Z (upward direction Z) and the direction Y. It is a wall to be installed.

  As shown in FIG. 2, a plurality of positioning protrusions 31 are arranged at a predetermined pitch in the cell stacking direction X on the upper surface 11a side of the outer case. In this way, a set of positioning convex portions 31 arranged in a plurality at a predetermined pitch in the cell stacking direction X is arranged in another set at a predetermined interval in the direction Y on the upper surface 11a side of the outer case.

  Between the two sets of positioning protrusions 31, the two sets of bus bars 20, or the two sets of electrode terminals 12 that are arranged at a predetermined interval in the direction Y, there are two rows of guide walls 34 a extending in the cell stacking direction X. The wiring guide part 34 is provided integrally with the cover part 30. The two rows of guide walls 34a are erected on the upper surface 11a side of the outer case with a predetermined interval in the direction Y. A wiring passage 34b extending in the cell stacking direction X is provided between the guide walls 34a.

  The wiring passage 34b is a passage provided above the upper surface 11a of the exterior case and the smoke exhausting duct 60, and a large number of voltage detection lines 72 extending from terminals 71 serving as detection portions installed on the bus bar 20 on the battery cell 10 side. It is a housing portion that houses (an example of a detection line). In each of the two rows of guide walls 34a in the wiring guide portion 34, a wiring opening portion 34a1 is formed with a predetermined interval in the cell stacking direction X. The wiring opening 34a1 has a shape that is cut out in a rectangular shape downward from the upper end of the guide wall 34a, and has a shape in which the upper end is open and the lower end is closed.

  A large number of voltage detection lines 72 are communication lines extending from a terminal 71 that is fixed by caulking to a part of the bus bar 20, welding, crimping, coupling by holding using a spring force, or the like. As shown in FIG. 2, each voltage detection line 72 is routed from the end of the bus bar 20 in the Y direction toward the center, passes over the bus bar 20, and opens the wiring opening 34 a 1 of the wiring guide portion 34. To the wiring path 34b.

  The assembled voltage detection lines 72 become a cable 70 bundled together, and reach the battery monitoring unit through the wiring passage 34b so as to be placed and wired above the smoke exhausting duct 60. In this way, the wiring guide part 34 contributes to good and orderly wiring of the voltage detection line 72 that does not interfere with other parts, protects the voltage detection line 72 from contact with other parts and external force acting from the outside, It has the function of wiring so as not to damage it. As shown in FIG. 4, the cable 70 includes an outer tube 73 that insulates and encloses the conductor portions 72 a of the plurality of voltage detection wires 72. The cross-sectional shape of the outer tube 73 is a flat shape whose height in the height direction is shorter than the length in the horizontal direction. Therefore, the cable 70 is a so-called flat flat cable.

  The flat cable shown in FIG. 4 has voltage detection lines 72, in other words, conductive portions 72a arranged in a line in the height direction, but the transverse shape of the cable 70 is more lateral than the height direction. If the length is short, the conductive portions 72a may be arranged in two or more rows in the height direction.

  As shown in FIG. 4, the assembled battery 1 includes a wiring protection cover as a wiring protection member that covers the cable 70 that is protected by the wiring guide 34 on the side and is wired to the wiring passage 34 b from above, and protects it from the outside. 80. The wiring protective cover 80 is attached to the upper end portion of the guide wall 34a so as to cover the wiring guide portion 34 with the upper portion opened in a state in which the cable 70 is installed in the wiring passage 34b, so that the cable 70 is connected from above. Protect. The wiring protection cover 80 is formed of a synthetic resin such as polypropylene (PP resin), for example.

  According to this configuration, the lower portion of the cable 70 is protected by the smoke exhaust duct 60, and the upper portion of the cable 70 is protected from the outside by the wiring protection cover 80. For this reason, even when an external load is applied in assembling work, maintenance, etc., it is possible to prevent the external force from directly acting on the cable 70 and prevent problems such as cracks and disconnections.

  Each bus bar 20 has a posture in which the rear surface side of the bus bar convex portion protruding upward faces the positioning convex portion 31, and the first terminal fitting opening 23 and the second terminal fitting opening 24 are electrode terminals to be connected. 12 and is arranged. That is, when the step of connecting the electrode terminals 12 to be connected to each other by the bus bar 20 is performed, each bus bar 20 is placed in a posture in which the top of the bus bar convex portion 22 is directed upward Z and the terminal connection portion 21 is maintained in the horizontal direction. Is positioned so that the back side of the bus bar convex portion faces the positioning convex portion 31, and the electrode terminal 12 is fitted into the first terminal fitting opening 23 and the second terminal fitting opening 24. With this positioning structure, the bus bar 20 is installed at an appropriate position in the cell stacking direction X, and the electrode terminal 12 to be connected can be accurately inserted into the both fitting openings 23 and 24.

  Further, after the positive electrode terminal and the negative electrode terminal are fitted into the first terminal insertion opening 23 and the second terminal insertion opening 24, the terminal connection of the bus bar 20 is performed by welding such as laser welding or arc welding. It is joined to the part 21.

  Furthermore, the assembled battery 1 is provided so that two or more may be arranged in the cell lamination direction X, and it may be provided so that the bus-bar convex part 32 may be interposed between the adjacent bus bars 20. The top portion of the bus bar-to-bus bar convex portion 32 has electrical insulation and protrudes upward from the positioning convex portion 31. That is, when the bus bar 20 is to be installed at an appropriate position, the bus bar-to-bus bar convex portion 32 is interposed as a partition wall that separates the bus bars 20 adjacent to each other in the cell stacking direction X. With this configuration, the displacement of the bus bar 20 in the cell stacking direction X is restricted, so that the positioning function can be exerted and the adjacent bus bars 20 are separated from each other as a partition wall, thereby preventing the contact between the two. Short circuit between bus bars can be prevented.

  Further, the portion corresponding to the positioning convex portion 31 may be constituted by a component separate from the cover portion 30 and the case 40. In this case, for example, the portion is a member provided between the battery cells 10 and can be formed integrally with a resin spacer member that forms the inter-cell passage 50 between the battery cells 10.

  When electrically connecting the electrode terminals 12 to be connected in adjacent battery cells 10, the back side of the bus bar convex portion with the bus bar convex portion 22 facing upward with respect to the assembled battery to which the cover portion 30 is attached. The bus bar 20 is brought close to the positioning projection 31 so as to face the positioning convex portion 31 and positioned with respect to the battery cell 10. Then, the position of the bus bar 20 is finely adjusted, and the electrode terminal 12 is fitted into the first terminal fitting opening 23 and the second terminal fitting opening 24. This process is performed for all bus bars 20 installed in the assembled battery 1. Since the position of the bus bar 20 in the cell stacking direction X is regulated by positioning the back surface of the bus bar convex portion facing the positioning convex portion 31, the step of fitting each electrode terminal 12 into the terminal fitting opening 23, 24 is performed. This contributes to quick operation, and prevents the bus bar 20 from touching a component that should not be touched, thereby preventing an inappropriate connection such as a short circuit or damage to the component.

  Further, at the position corresponding to the space between the bus bars 20 adjacent to each other in the cell stacking direction X, there is an inter-bus bar convex portion 32 that stands higher above the positioning convex portion 31. For this reason, even when the bus bar 20 is disposed, even if the bus bar 20 is displaced, the end of the terminal connection portion 21 contacts the tall inter-bus bar convex portion 32, so that the adjacent bus bars 20 are adjacent to each other. So that they do not overlap each other. In other words, even if each bus bar 20 is placed at an approximate position from above, each bus bar 20 is disposed so as not to interfere with the other bus bars 20 by the tall inter-bus bar convex portion 32, and further, The electrode terminal 12 is disposed at a position where the electrode terminal 12 can be appropriately connected by the positioning action of the back surface side and the positioning convex portion 31.

  Next, the effect which the assembled battery 1 of this embodiment brings is demonstrated. The assembled battery 1 is provided on the upper surface 11a of the outer case, the safety valve 13 that breaks when the internal pressure of the battery cell 10 becomes an abnormal pressure, the outer case that insulates between the bus bar 20 and the outer case 11 and excludes at least the safety valve 13 The inner wall surface 60a is exposed so as to expose the safety valve 13 having heat resistance and not covered with the cover portion 30 to the internal smoke passage 61. And a plurality of voltage detection lines 72 extending from terminals 71 electrically connected to the plurality of battery cells 10 in order to obtain information on the state of the plurality of battery cells 10. And a cable 70 placed and wired above the smoke exhausting duct 60.

  According to this configuration, even if high-temperature gas flows through the passage in the smoke exhaust duct 60 due to the breakage of the safety valve 13, the cable 70 is placed and wired above the heat-resistant smoke exhaust duct 60. As a result, the cable 70 can be protected from heat, and the covering portion of the cable 70 can be prevented from melting. Further, since the cable 70 is wired along the smoke exhaust duct 60 above the smoke exhaust duct 60, the space for wiring the cable 70 can be reduced, and the cable 70 can be wired and supported. The number of members can be reduced. Therefore, the assembled battery 1 that can protect the cable 70 from heat, reduce the size, and reduce the number of components is obtained.

  In addition, since the cover part 30 is formed of a heat-resistant resin, the cover part 30 also has heat resistance, so the temperature resistance performance around the smoke exhaust duct 60 against high-temperature gas can be improved. . Therefore, the protection of the cable 70 from heat can be further increased.

  In addition, the smoke exhaust duct 60 has higher heat resistance than the cover part 30, so that the heat exhaust duct 60 has higher heat resistance than the cover part 30 and can directly contact the high temperature gas. In order to ensure the temperature resistance performance of the duct 60, the cable 70 can be more reliably protected from the high temperature gas.

  Further, the smoke exhausting duct 60 includes a flange portion 60b that comes into close contact with the upper surface 11a of the outer case including the portion where the safety valve 13 is provided. According to this, the degree of adhesion between the smoke exhaust duct 60 and the upper surface 11a of the exterior case is increased by the flange portion 60b, and the gas barrier property to the outside is improved, so that the battery cell 10 is outside when it is abnormal. The effect of preventing gas leakage can be improved.

  Further, the cable 70 includes an outer tube 73 that insulates and encloses the conductor portions 72a of the plurality of voltage detection wires 72, and the outer tube 73 has a cross-sectional shape whose height direction length is longer than the horizontal length. It is a short flat shape. According to this, since the height direction length of the cable 70 which insulates and accommodates a plurality of electric wires can be suppressed, the overall height of the assembled battery 1 can be suppressed. In addition, since a plurality of electric wires for acquiring information related to the plurality of battery cells 10 are stored in a state of being bundled together by the outer tube 73, the man-hour required for wiring in assembling the assembled battery 1 can be further reduced. .

(Other embodiments)
In the above-described embodiment, the preferred embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. It is.

  The cover portion 30 in the above embodiment is a separate component from the case 40 in which the plurality of battery cells 10 are accommodated, and is integrally attached to the case 40 by the engagement of the claw portion 33 and the accommodation portion 41. However, the present invention is not limited to such a form. Further, the cover part 30 may be a part formed integrally with the case 40. For example, the cover portion 30 is an integrally formed member connected to the case 40 by a hinge portion. In this case, the cover portion 30 may be covered with the hinge portion as a fulcrum so as to cover the case 40, and the cover portion 30 may be fixed to the case 40 by engagement means provided on the opposite side of the hinge portion.

  The smoke exhaust duct 60 in the above embodiment is a separate member from the cover part 30, but the present invention is not limited to this form, and the smoke exhaust duct 60 and the cover part 30 are the same integral member. It may be.

  The smoke exhaust duct 60 in the above embodiment has a U-shaped cross section, and the smoke exhaust passage 61 through which the safety valve 13 is exposed is surrounded by the inner wall of the smoke exhaust duct 60. The present invention is not limited to this form. For example, the smoke exhaust passage 61 is not surrounded only by the inner wall of the smoke exhaust duct 60 but is surrounded by the inner wall of the smoke exhaust duct 60 and the cover portion 30. Form may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Battery pack 10 ... Battery cell 11 ... Outer case 11a ... Upper surface of outer case (end surface of outer case)
DESCRIPTION OF SYMBOLS 12 ... Electrode terminal 13 ... Safety valve 20 ... Bus bar 30 ... Cover part 50 ... Inter-cell passage 60 ... Smoke duct (duct part)
60a ... Inner wall surface 60b ... Flange part 61 ... Smoke exhaust passage (passage)
70 ... Cable 71 ... Terminal 72 ... Voltage detection line (detection line)
72a ... Conductor part 73 ... Exterior tube 80 ... Wiring protection cover (wiring protection member)
X: Cell stacking direction

Claims (6)

In the battery cell (10) adjacent to the stacking direction (X), a plurality of battery cells (10) having a positive electrode terminal and a negative electrode terminal projecting upward from the outer case (11) are stacked. An assembled battery (1) configured to be energized by connecting the electrode terminals to be connected with a bus bar (20),
A safety valve (13) provided on an end surface (11a) of the outer case and breaking when the pressure inside the battery cell becomes an abnormal pressure;
A cover portion (30) provided to insulate between the bus bar (20) and the outer case (11) of the battery cell and cover at least an end surface portion of the outer case excluding the safety valve (13);
A duct part (60) having heat resistance, and an inner wall surface (60a) is exposed so as to expose the safety valve (13) not covered with the cover part (30) to a passage (61) formed therein. A duct portion (60) provided to face the safety valve (13);
A cable (70) formed by bundling a plurality of detection lines (72) extending from terminals (71) electrically connected to the plurality of battery cells in order to obtain information on the state of the plurality of battery cells, A cable (70) placed and wired above the duct portion (60);
An assembled battery comprising:   The assembled battery according to claim 1, wherein the cover part (30) is formed of a heat-resistant resin.   The assembled battery according to claim 1 or 2, wherein the duct part (60) has higher heat resistance than the cover part (30).   The said duct part (60) is provided with the flange part (60b) closely_contact | adhered to the end surface (11a) of the said exterior case containing the site | part in which the said safety valve (13) is provided. The assembled battery according to any one of claims 3 to 4. The cable (70) includes an exterior tube (73) that insulates and encloses the conductor portions (72a) of the plurality of detection wires (72),
The assembled battery according to any one of claims 1 to 4, wherein a cross-sectional shape of the outer tube (73) is a flat shape whose height in the height direction is shorter than the length in the horizontal direction. .   The wiring protection member (80) which further covers the cable (70) wired above the duct portion (60) from above and protects from the outside is provided. The assembled battery according to one item.

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