JP4461940B2 - Assembled battery - Google Patents

Description

  The present invention relates to an assembled battery in which a voltage detection terminal for detecting a voltage for each cell is attached in a floating state.

  In recent years, in response to growing environmental awareness, there is a movement to shift the power source of automobiles from an engine using fossil fuel to a motor using electric energy. For this reason, the technology of the battery that serves as a power source for the motor is also rapidly developing.

  An automobile is desired to be mounted with a battery that is small and light and can be charged and discharged with a large amount of electric power and has excellent vibration resistance and heat dissipation. As an assembled battery capable of supplying large electric power, there is a battery as shown in Patent Document 1 below.

The assembled battery disclosed in Patent Document 1 is configured by placing a plurality of thin unit cells on a positioning plate and laminating the positioning plates. With such a structure, the energy density, vibration resistance, and heat dissipation of the assembled battery are improved.
Japanese Patent Laid-Open No. 2004-22496

  Since the assembled battery of Patent Document 1 is formed by stacking thin unit cells, the energy density is higher than that of a conventional assembled battery configured using non-thin unit cells, and the assembled battery has the same power capacity. The size can be reduced. For this reason, the assembled battery comprised with the thin single battery is suitable as a battery for motor vehicles from the point of a small size and a high energy density.

  However, in order to improve the reliability of the assembled battery, it is necessary to constantly monitor the charge / discharge capacity of each unit cell and adjust the balance. For this reason, it is necessary to provide the assembled battery with a mechanism for detecting the voltage of each cell.

  In order to detect the voltage for each unit cell, it is only necessary to connect a voltage detection harness to each electrode tab of the unit cell. However, if the connection was made at the stage of assembling the assembled battery, the assembly efficiency was poor. Not right.

  Therefore, a voltage detection terminal is provided in advance on the electrode tab of each unit cell, and after stacking the unit cells having the voltage detection terminal, the connector to which the voltage detection harness is connected is connected to the voltage detection terminal. It is conceivable to connect a plurality of voltage detection terminals and a plurality of voltage detection harnesses all at once at a time. There was a problem that the position was varied and it was difficult to connect the connector.

  In order to achieve the above object, an assembled battery according to the present invention is an assembled battery in which a plurality of plate-like frames on which a single battery is placed are stacked in the thickness direction of the frame. A voltage detection terminal for detecting the voltage of the battery is held movably in the thickness direction of the frame between other frames adjacent to the frame.

  The voltage detection terminal for detecting the voltage of the unit cell is held movably in the frame thickness direction (in a floating state) between the frames. For this reason, each voltage detection terminal can move in the thickness direction of the frame within a certain range. The thickness of each unit cell and the thickness of each frame are not exactly the same and vary within a certain range. However, if the voltage detection terminal is left floating in this way, variations in the thickness can be absorbed. The workability when the connector is simultaneously connected to the plurality of voltage detection terminals is improved.

  According to the assembled battery according to the present invention configured as described above, since the voltage detection terminals are held movably in the thickness direction between the frames, it is easy to connect the connectors that are simultaneously attached to the plurality of voltage detection terminals. Thus, the assembly workability of the assembled battery is improved.

Hereinafter, embodiments of the assembled battery according to the present invention will be described by dividing them into [Embodiment 1] to [Embodiment 3].
[Embodiment 1]
In the assembled battery described in the first embodiment, four unit cells are arranged in a width direction on a frame, and 24 frames are stacked to form a battery unit. Pressurized and held integrally. The battery unit has 96 unit cells, and a voltage detection terminal for detecting the voltage of the unit cell is attached to both sides of each frame in a floating state by a guide projection, and voltage detection is performed on the voltage detection terminal. A connector to which a wire is connected is attached so that the voltage of each cell can be detected from an external control device.

(Battery structure)
FIG. 1 is a perspective view showing an external appearance of an assembled battery according to the present invention, and FIG. 2 is a schematic partial sectional view in the direction of FIGS. 1A-A for showing a stacked state of main components of the assembled battery shown in FIG. 3 is a partially enlarged cross-sectional view of FIG. 2, FIG. 4 is a diagram showing the connection relationship between the bus bar and through bolts of the assembled battery shown in FIG. 1, and FIG. 5 is a single unit constituting the assembled battery shown in FIG. It is a figure which shows typically the connection state between batteries.

  As shown in FIG. 1, the assembled battery 100 according to the present invention pressurizes a battery unit 200 in which a plurality of plate-shaped frames are stacked in the thickness direction with heat sinks 300 and 350 sandwiched from both sides in the stacking direction. They are held together.

  The frame (not shown) has four holding portions for arranging four flat cells in parallel. In the assembled battery 100, 24 frames are stacked, and an intermediate heat sink 325 is inserted every six stacking directions. Therefore, the assembled battery 100 includes four unit cells arranged in parallel, each having 24 units, and has a total of 96 unit cells.

  The heat sinks 300 and 350 are fixed by attaching six pressure units connecting the heat sinks with nuts 310A to 310F. The pressure unit has shafts fixed by nuts 310 </ b> A to 310 </ b> F attached to both ends of a tension coil spring, and is attached between the heat sinks 300 and 350, so that all the unit cells constituting the battery unit 200 are attached. Appropriate surface pressure is applied in the stacking direction.

  The laminated structure of the assembled battery 100 is as shown in FIGS. Note that these drawings are simplified for easy understanding of the invention. In these drawings, only four frames are provided between the heat sink 350 and the intermediate heat sink 325, but actually six frames are provided.

  An insulating washer 212, which is an insulating member, is embedded at one end of a frame 210 (insulating washer embedded frame) that constitutes a small module, and a peripheral portion 216 of the unit cell 214 is supported around the frame 210. A peripheral support portion 218 is formed. The central portion of the frame 210 surrounded by the peripheral edge support portion 218 in the frame 210 is opened, and the elements (heat sink 350 and unit cell 224) adjacent in the stacking direction and the exterior surface of the unit cell 214 come into direct contact with each other. ing. The other end of the frame 210 is provided with an opening 217A for ultrasonic welding of the electrode tab 215B of the unit cell 214 and the electrode tab 225B of the unit cell 224 adjacent in the stacking direction. The electrode tab 215A of the unit cell 214 is in contact with the insulating washer 212 and a bus bar 260 described later. The insulating washer 212 is thicker than the frame 210 and thinner than the unit cell 214. That is, the thickness of the insulating washer 212 is set to a thickness between the thickness of the frame 210 and the unit cell 214. All of the insulating washer embedded frames constituting the assembled battery 100 use such thickness-related insulating washers. Further, the thickness of the unit cell 214 is larger than the thickness of the frame 210, and the position of the stack surface of the unit cells 214 mounted on the frame 210 is higher than the position of the stack surface of the frame 210. However, this is to improve the battery life by applying a sufficient surface pressure to the unit cell 214 when stacked. All unit cells and the frame constituting the assembled battery 100 have such a thickness relationship.

  A conductive washer 222, which is a conductive member, is embedded at one end of the frame 220 (conductive washer embedded frame), and a peripheral support 228 similar to the frame 210 is formed around the frame 220. A central portion of the frame 220 surrounded by 228 is opened. The other end of the frame 220 is provided with an opening 217B similar to the frame 210. One electrode tab 225A of the unit cell 224 is in contact with the conduction washer 222, and is connected to the electrode tab 235A of the unit cell 234 via the conduction washer 222. The conductive washer 222 is thicker than the frame 220 and thinner than the unit cell 224. That is, the thickness of the conductive washer 222 is set to a thickness between the thickness of the frame 220 and the unit cell 224. This is because such a thickness relationship allows the electrode tab 225 </ b> A and the conductive washer 222 to be in contact with each other while applying a desired surface pressure to the unit cell 224. All conductive washer embedded frames constituting the assembled battery 100 use such thickness-related conductive washers.

  The electrode tab 215B of the unit cell 214 that is positioned and supported on the frame 210 and the electrode tab 225B of the unit cell 224 that is positioned and supported on the frame 220 are shown from both sides of the openings 217A and 217B provided in the respective frames. Pressure is applied with a jig that does not, and ultrasonic welding is performed.

  An insulating washer 232 is embedded at one end of the frame 230 (insulating washer embedded frame), and a peripheral support portion 238 similar to the frame 210 is formed around the frame 230, and is surrounded by the peripheral support portion 238. A central portion of the frame 230 is opened. An opening 217 </ b> C similar to that of the frame 210 is provided at the other end of the frame 230. One electrode tab 235 </ b> A of the unit cell 234 is in contact with the insulating washer 232 and the conductive washer 222. When the frame 220 and the frame 230 are laminated, the electrode tab 235B of the unit cell 234 comes into contact with the welded lower electrode tabs 215B and 225B due to the presence of the opening 217C, so that insulation is provided above the electrode tab 225B. Tape 250A is affixed.

  A conductive washer 266 is embedded in one end of the frame 265 (conductive washer embedded frame), and a mounting portion 273 for an intermediate heat sink 325 laminated on the frame 265 is formed. Further, a peripheral support portion 278 similar to the frame 210 is formed around the frame 265, and a central portion of the frame 265 surrounded by the peripheral support portion 278 is opened. The other end of the frame 265 is provided with an opening 277D similar to the frame 210. One electrode tab 275 </ b> A of the unit cell 274 is in contact with the conductive washer 266. Note that the thickness of the conductive washer 266 is equal to the thickness of the insulating washer or the conductive washer (the thickness of the insulating washer = the thickness of the conductive washer) plus the thickness of the intermediate heat sink 325.

  2 and 3, only four frames are interposed between the heat sink 350 and the intermediate heat sink 325, but actually, the lower layer (insulating washer) is interposed between the heat sink 350 and the intermediate heat sink 325. Six frames are stacked in the following order: embedded frame)-(conductive washer embedded frame)-(insulated washer embedded frame)-(conductive washer embedded frame)-(insulated washer embedded frame)-(conductive washer embedded frame).

  An intermediate heat sink 325 is mounted on the mounting portion 273 of the frame 265. The intermediate heat sink 325 and the conductive washer 266 are insulated by the frame 265.

  On the upper side of the intermediate heat sink 325, (six frames)-(intermediate heat sink)-(six frames)-(intermediate heat sink)-(six frames) -heat sink 300 are stacked in this order. The frame 240 immediately below the heat sink 300 has the same configuration as the frame 220. That is, the conductive washer 242 is embedded in the frame 240, a peripheral support portion 248 similar to the frame 210 is formed, and a central portion of the frame 240 surrounded by the peripheral support portion 248 is opened. The other end of the frame 240 is provided with an opening 217E similar to the frame 210. One electrode tab 245 </ b> A of the unit cell 244 is in contact with the conductive washer 242. Although not shown, the electrode tab 245B of the unit cell 244 is ultrasonically welded to the electrode tab of the unit cell located therebelow. An insulating tape 250B is affixed on the upper side of the electrode tab 245B in order to insulate from the heat sink 300.

  All the laminated frames are fixed by through bolts 270 and bolts 271. An insulating washer 278 and a washer 279 are interposed between the nut 271 and the conductive washer 242, but the insulating washer 278 is for insulating the bus bar 262, and the washer 279 is made of ceramic and is used for preventing damage. Respectively.

  As shown in FIG. 4, the heat sink 350 is provided with a bus bar 260 for electrically connecting the stacked unit cells to the unit cells adjacent in the arrangement direction of the unit cells. The bus bar 260 is insulated from the heat sink 350 by an insulating washer 261. A through bolt 270 whose periphery is insulated is mechanically connected to the bus bar 260. The bus bars 260, 262, 264 and through bolts 270, 275, 280, 285 existing in the assembled battery 100 are connected as shown in the figure. The through bolts 270, 275, 280, 285 are erected from the bottom surface of the heat sink 350, and the through bolts 270, 275, 280, 285 connect the stacked unit cells in series by the bus bars 260, 262, 264.

  2 and 3, if these figures represent the AA cross section of FIG. 4, the reference numeral 262 indicates the member 263 connected to the power terminal 450A, and these figures indicate the BB of FIG. If the cross section is represented, the number 262 represents each bus bar.

  When the heat sinks 300 and 350 are fixed by bolts and nuts 310A to 310F with the battery unit 200 interposed therebetween and the four through bolts are tightened by the four connecting terminals, the single battery constituting the assembled battery 100 is shown in FIG. 5 are connected in series.

  The assembled battery 100 has a four-row unit cell stack in which 24 unit cells are stacked. As shown in FIG. 5, each unit cell stack 400, 410, 420, 430 is a single unit. The batteries are all connected in series in the stacking direction. That is, the connection between the cells on the left side of the cell stack 400 is performed by ultrasonic welding, and the insulation between the cells (the square mark in the drawing) is the insulating tape (for example, FIG. 2 250A, 250B). On the other hand, the cells on the right side of the cell stack 400 are connected to each other by a conduction washer (for example, 222, 266 in FIG. 2), and the cells are insulated (the triangular marks in the figure). ) Is done by insulating washers. Therefore, when the assembled battery 100 is assembled, all the unit cells constituting the unit cell stack 400 are connected in series. In the other cell stacks 410, 420, and 430, all the cells are connected in series with the same structure.

  Each cell stack 400, 410, 420, 430 is further connected in series by bus bars 260, 262, 264 (see FIG. 4) attached to a heat sink (300, 350 in FIG. 2). In this way, all the single cells constituting the assembled battery 100 are connected in series. When such a connection method is adopted, the connection portions of the power terminals 450A and 450B can be made only in one direction (upper side of the heat sink 300), so that power wiring after the assembled battery is easily installed and productivity is improved. .

  The overall structure of the assembled battery 100 is as described above. Next, main components constituting the assembled battery will be described in detail.

(Single cell)
The unit cell 214 used in this embodiment is a rectangular flat-type laminated secondary battery as shown in FIG. 6, and includes a laminated-type power generation element in which at least a positive electrode plate and a negative electrode plate are sequentially laminated. For example, it has a structure as disclosed in Japanese Patent Application Laid-Open No. 2003-059486. A laminating film is used as the exterior material of the unit cell 214, and the built-in power generation element is sealed by heat-sealing the peripheral part of the unit cell 214. Electrode tabs 215 </ b> A and 215 </ b> B are drawn out from both side surfaces of the unit cell 214 in the longitudinal direction. The electrode tab 215A is a positive electrode tab, and is made of, for example, an aluminum thin plate having a thickness of about 0.2 mm. On the other hand, the electrode tab 215B is a negative electrode tab, and is composed of, for example, a thin copper plate having a thickness of about 0.2 mm. Insertion holes 272A and 272B for inserting through bolts (270 in FIG. 2) are opened in both electrode tabs 215A and 215B. The peripheral portion 216 of the unit cell 214 that is heat-sealed and joined is positioned and held by a holding portion formed on the frame. The stacking direction of the unit cells is the same as the stacking direction of the positive electrode plate and the negative electrode plate constituting the power generation element.

  In the present embodiment, the assembled battery 100 is configured by using a unit cell in which electrode tabs of different polarities are attached to two opposing sides as shown in FIG. 6, but JP-A-2003-059486 is disclosed. 1, the assembled battery 100 may be configured using a unit cell in which electrode tabs of different polarities are attached to only one side. However, when this type of single cell is used, the structure of the frame and the method of connecting the single cells are greatly different from those of the present embodiment. Further, in this embodiment, one flat battery is a single battery, but a plurality of batteries connected in series, a plurality of batteries connected in parallel, or a plurality of batteries connected in series and parallel are connected. The batteries may be held on the frame as single cells.

(flame)
There are two types of frames used in this embodiment: an insulating washer embedded frame 210 as shown in FIG. 7A and a conductive washer embedded frame 220 as shown in FIG. 7B.

  The insulating washer embedded frame 210 has an insulating washer 212 embedded in one end portion 210A thereof. The thickness of the insulating washer 212 is slightly larger than the thickness of the frame 210 and smaller than the thickness of the unit cell.

  The conductive washer embedded frame 220 has a conductive washer 222 embedded in one end 220A thereof. Similar to the insulating washer, the thickness of the conductive washer 222 is slightly larger than the thickness of the frame 220 and smaller than the thickness of the unit cell. The conduction washer has a function of electrically connecting one electrode tab of the unit cell held by the frame to one electrode tab of the unit cell held by another frame adjacent in the stacking direction.

  As shown in FIG. 7, each of the frames 210 and 220 includes a holding unit that positions and holds four unit cells arranged on one plane. That is, it includes peripheral support portions 218 and 228 that support at least one peripheral portion 216 of the unit cell 214 (see FIG. 6), and a positioning unit that positions the unit cell 214. The positioning portion is a portion that is formed around the peripheral edge supporting portions 218 and 228 and is shaped so that the peripheral edge of the unit cell 214 is fitted. Locating pin insertion holes (not shown) for inserting locating pins (not shown) are opened at two corners of the frames 210 and 220.

  The position of the cell is fixed by the positioning part of the frame, and the peripheral part is supported by the peripheral support part. The peripheral part of the cell and the peripheral support part of the frame are temporarily fixed with a double-sided tape. Therefore, the unit cell can be easily transported in a state of being placed on the frame in the manufacturing stage.

  At the end of each frame (front side and back side in FIG. 7), a voltage detection terminal 500 as schematically shown in FIG. 8 is guided in the thickness direction of the frame by a guide projection 510 passing through a guide hole (described later). It is held so as to be movable. That is, the voltage detection terminal 500 is held in a floating state with another frame adjacent to the frame. The voltage detection terminal 500 is a terminal provided for detecting the voltage of each unit cell, and is later joined to the electrode tab of the unit cell.

  As shown in FIG. 7, since each of the cells 210 is held in the frames 210 and 220, the voltage detection terminal 500 is connected to the long side of one of the frames (the front side or the back side in FIG. 7). 4 pieces each. In this embodiment, a voltage detection terminal 500 is provided on the front side of FIG. 7 in a certain frame, and a voltage detection terminal 500 is provided on the back side of FIG. For this reason, a certain frame is provided with a guide projection 510 on the long side on the near side, and an insertion hole (not shown) for inserting the tip portion of the guide projection 510 on the long side on the back side. An insertion hole is provided on the long side on the near side of the frame laminated on the frame, and a guide protrusion 510 is provided on the long side on the far side.

  Therefore, when the frames are stacked to form the battery unit 200, as shown in FIG. 9, the voltage detection terminals 500 are arranged in a row at regular intervals in the frame thickness direction, as shown in FIG. It will be arranged one by one. As shown in FIG. 10, these voltage detection terminals 500 are collectively connected by a connector 600 having connection ports 600 </ b> A to 600 </ b> C that can be simultaneously connected to the three voltage detection terminals 500. Although not shown in the drawing, the electric wire drawn out from the connector 600 is connected to an external control device that detects the voltage of each unit cell and controls its charge / discharge.

  FIGS. 11-14 is a figure with which it uses for description of the holding means concerning this Embodiment. As shown in FIG. 11, a columnar guide protrusion 510 whose height is lower than the thickness of the frame 210 is erected on the frame 210. Since the frame 210 is molded from resin, the guide protrusion 510 is formed integrally with the frame 210 when the frame 210 is molded. When the frame 210 is formed of a material other than resin such as paper, the guide protrusion 510 is attached to the frame 210 by adhesion or fitting.

  The voltage detection terminal 500 has a guide hole 520 into which the guide protrusion 510 is inserted. The guide hole 520 can be easily inserted into the guide protrusion 510, and its diameter is made larger than the outer diameter of the guide protrusion 510 so that the voltage detection terminal 500 can easily move up and down along the guide protrusion 510. Yes. When the voltage detection terminal 500 is attached to the guide protrusion 510, the position of the voltage detection terminal 500 in the frame surface direction (two-dimensional direction on the surface of the frame 210) is restricted, and the voltage detection terminal 500 moves in the thickness direction of the frame 210. Will be guided.

  On the other hand, the frame 220 stacked on the frame 210 is provided with an insertion hole 530 for inserting the guide protrusion 510 of the frame 210. The insertion hole 530 is formed so as to penetrate the frame 220, and the inner diameter thereof is formed to be the same as or slightly larger than the outer diameter of the guide protrusion 510 so that the guide protrusion 510 fits firmly.

  When the frame 210 and the frame 220 are stacked, as shown in FIG. 12, the guide protrusion 510 of the frame 210 is fitted into the insertion hole 530 of the frame 220, and the voltage detection terminal 500 is held in a floating state between the frames 210 and 220. Is done.

The situation of being held in the floating state is as shown in FIGS. 13 is a view of the stacked state shown in FIG. 12 as viewed from the front side of the drawing, and FIG. 14 is a cross-sectional view taken along line AA of FIG. The unit cells 214 and 224 are thicker than the thicknesses of the frames 210 and 220 (see FIG. 14). Therefore, in the state where the frames 210 and 220 are laminated, there is a play of the dimension L (around 0.5 mm) obtained by subtracting the thickness of the frame 220 from the thickness of the unit cell 224 between the frames 210 and 220. The electrode tab 215A of the unit cell 214 and the voltage detection terminal 500 are ultrasonically bonded. However, since the electrode tab 215A has a thickness of about 0.2 mm, the voltage detection terminal 500 is guided between the frames 210 and 220. It can move freely along the protrusion 510.
[Embodiment 2]
The assembled battery described in the second embodiment has the same structure as the assembled battery described in the first embodiment, except for the structure for attaching the voltage detection terminal. Therefore, in the present embodiment, only the portion of the voltage detection terminal mounting structure will be described in detail based on the drawings. In this embodiment, the voltage detection terminal is attached in a floating state by a guide pin, and a connector having a voltage detection line connected to the voltage detection terminal is attached so that the voltage of each unit cell can be detected from an external control device. ing.

  15 to 18 are views for explaining the holding means according to this embodiment. FIG. 15 is a diagram for explaining the case where the voltage detection terminal is attached with a guide pin, and FIG. 16 is a diagram showing a state where the voltage detection terminal is attached to the frame.

  As shown in FIG. 15, an embedding hole 560 for fixing the guide pin 550 is opened in the frame 210. Since the embedded hole 560 is provided to firmly fix the guide pin 550 to the frame 210, the inner diameter of the embedded hole 560 is the same as or slightly larger than the outer diameter of one end (lower end) of the guide pin 550. Is formed. In this embodiment, the guide pin 550 is press-fitted into the embedding hole 560 and attached, but a screw may be formed at one end of the guide pin 550 and the guide pin 550 may be screwed into the frame 210 and attached.

  The guide pin 550 is a cylindrical pin whose height is lower than the thickness of the frame 210, and has a retaining portion 570 having a larger outer diameter than the guide hole 520 of the voltage detection terminal at the other end (upper end). .

  The voltage detection terminal 500 has a guide hole 520 into which the guide pin 550 is inserted. The guide hole 520 can be easily inserted into the guide pin 550, and the diameter of the voltage detection terminal 500 can be easily moved up and down along the guide pin 550 so that the voltage detection terminal 500 does not come out of the retaining portion 570. Is larger than the outer diameter of the guide pin 550 and smaller than the outer diameter of the retaining portion 570. When the voltage detection terminal 500 is attached to the guide pin 550, the floating state as shown in FIG. 16 is established, the position of the voltage detection terminal 500 in the frame surface direction (two-dimensional direction on the surface of the frame 210) is regulated, and voltage detection is performed. The movement of the terminal 500 in the thickness direction of the frame 210 is guided between the frame surface and the retaining portion 570. The voltage detection terminal 500 is ultrasonically bonded to the electrode tab 215A of the unit cell 214.

The situation of being held in the floating state is as shown in FIGS. 17 is a view of the stacked state shown in FIG. 16 as viewed from the front side of the drawing, and FIG. 18 is a cross-sectional view taken along line BB of FIG. The unit cells 214 and 224 are thicker than the thicknesses of the frames 210 and 220 (see FIG. 18). Therefore, in the state where the frames 210 and 220 are laminated, there is a play of the dimension L (around 0.5 mm) obtained by subtracting the thickness of the frame 220 from the thickness of the unit cell 224 between the frames 210 and 220. The electrode tab 215A of the unit cell 214 and the voltage detection terminal 500 are ultrasonically bonded, but the thickness of the electrode tab 215A is about 0.2 mm, so that the voltage detection terminal 500 is between the frames 210 and 220. It can freely move up and down along the guide pin 550 between the surface and the retaining portion 570. In FIG. 18, the guide pin embedding hole 580 is opened at the position corresponding to the guide pin 550 of the frame 220, but the protruding height of the guide pin 550 from the surface of the frame 210 is within the above-mentioned dimension L. If so, the guide pin embedding hole 580 may not be opened.
[Embodiment 3]
The assembled battery described in the third embodiment also has the same structure as the assembled battery described in the first embodiment, except for the structure for attaching the voltage detection terminal. Therefore, also in this embodiment, only the portion of the voltage detection terminal mounting structure will be described in detail based on the drawings. In the present embodiment, the voltage detection terminal is attached in a floating state by the voltage detection terminal having the guide groove provided in the frame and the guide protrusion inserted into the guide groove, and the voltage detection line is connected to the voltage detection terminal. A connector is attached so that the voltage of each cell can be detected from an external control device. 19 to 22 are diagrams for explaining the holding means according to the present embodiment.

  19 and 20 are views for explaining the guide protrusions formed on the voltage detection terminal and the guide grooves provided on the frame.

  As shown in FIG. 19, the voltage detection terminal 500 has a guide protrusion 585 formed by bending at least one part of the outer periphery thereof into an L shape. The frame 210 is provided with a guide groove 590 that accommodates the guide protrusion 585 and holds it movably in the thickness direction of the frame. The length (depth) of the guide protrusion is formed such that the voltage detection terminal 500 does not come out of the guide groove 590 even if the voltage detection terminal 500 moves between the frame 210 and another frame adjacent thereto. .

  When the voltage detection terminal 500 is attached to the guide groove 590, the voltage detection terminal 500 is in a floating state between the frames, the position of the voltage detection terminal 500 in the frame surface direction (two-dimensional direction on the surface of the frame 210) is restricted, and the voltage detection terminal 500 The movement of the frame 210 in the thickness direction is guided between the frame surfaces by the guide protrusion 585 and the guide groove 590. The voltage detection terminal 500 is ultrasonically bonded to the electrode tab 215A of the unit cell 214.

  The situation of being held in the floating state is as shown in FIGS. 21 is a view of the stacked state shown in FIG. 19 as viewed from the front side of the drawing, and FIG. 22 is a cross-sectional view taken along the line CC of FIG. The unit cells 214 and 224 are thicker than the thicknesses of the frames 210 and 220 (see FIG. 22). Therefore, in the state where the frames 210 and 220 are laminated, there is a play of the dimension L (around 0.5 mm) obtained by subtracting the thickness of the frame 220 from the thickness of the unit cell 224 between the frames 210 and 220. The electrode tab 215A of the unit cell 214 and the voltage detection terminal 500 are ultrasonically joined. However, since the thickness of the electrode tab 215A is about 0.2 mm, the voltage detection terminal 500 is guided between the frames 210 and 220. It can move freely along the groove 590. Since the length of the guide protrusion 585 of the voltage detection terminal 500 is larger than the dimension L, the guide protrusion 585 does not come off the guide groove 590.

  As described above, in the present invention, the voltage detection terminals are held in a floating state between the frames. Therefore, the voltage due to the dimensional variation that occurs during the manufacture of the unit cell or the frame and the dimensional variation that occurs during the assembly of the assembled battery. The variation in the position of the detection terminals in the frame stacking direction can be absorbed, and the connection work of the connector for connecting a plurality of voltage detection terminals at the same time can be made efficient.

  Since the assembled battery according to the present invention is excellent in assemblability, it can be used in the field of manufacturing assembled batteries.

It is a perspective view which shows the external appearance of the assembled battery concerning this invention. FIG. 2 is a schematic partial cross-sectional view in the direction of FIG. 1A-A showing a stacked state of main components of the assembled battery shown in FIG. 1. It is a partially expanded sectional view of FIG. It is a figure which shows the connection relation of the bus bar and through-bolt of the assembled battery shown in FIG. It is a figure which shows typically the connection state between the single cells which comprise the assembled battery shown in FIG. It is a perspective view which shows the external appearance of a cell. It is a block diagram of each flame | frame of the assembled battery concerning this invention. It is an enlarged view of the flame | frame of the part to which the terminal for voltage detection is attached. It is a figure which shows the arrangement | sequence state of the voltage detection terminal in a battery unit, and the connector connected to it. It is an external view of a connector. FIG. 3 is a diagram for explaining a holding unit according to the first embodiment; FIG. 3 is a diagram for explaining a holding unit according to the first embodiment; FIG. 3 is a diagram for explaining a holding unit according to the first embodiment; FIG. 3 is a diagram for explaining a holding unit according to the first embodiment; It is a figure where it uses for description of the holding means concerning Embodiment 2. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 2. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 2. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 2. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 3. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 3. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 3. FIG. It is a figure where it uses for description of the holding means concerning Embodiment 3. FIG.

Explanation of symbols

100 battery packs,
200 battery unit,
210, 220, 230 frames,
212, 232 insulation washers,
214, 224, 234, 244, 274 cells,
215A, 215B, 225A, 225B, 235A, 235B, 245A, 245B, 275A electrode tabs,
216 rim,
217A, 217B, 217C, 217D, 217E opening,
218, 228, 238, 248 peripheral support,
222, 242 conductive washers,
250A, 250B insulating tape,
260, 262, 264 bus bars,
270, 275, 280, 285 through bolts,
272A, 272B insertion hole,
300, 350 heat sink,
310A-310F nut,
325 Intermediate heat sink,
380-385 mounting holes,
400, 410, 420, 430 cell stack,
450A, 450B power terminal,
500 Voltage detection terminal,
510 guide protrusion,
520 guide holes,
530 insertion hole,
550 guide pins,
560 embedding hole,
570 retaining part,
580 Guide pin buried hole,
585 guide protrusion,
590 guide groove,
600 connectors,
600A-600C connection port.

Claims (9)

A battery pack in which a plurality of plate-like frames on which a single battery is placed are stacked in the thickness direction of the frame,
The assembled battery is characterized in that a voltage detection terminal for detecting the voltage of the unit cell is held in the frame so as to be movable in the thickness direction of the frame with another frame adjacent to the frame. .   The group according to claim 1, wherein the frame is provided with holding means for guiding the movement of the frame in the thickness direction while restricting the position of the voltage detection terminal in the frame surface direction. battery.   Furthermore, the connector provided with the some connection port which can be simultaneously connected to these voltage detection terminals is attached to the several voltage detection terminals arranged in the thickness direction of the said frame. 2. The assembled battery according to 2.   4. The assembled battery according to claim 2, wherein the holding unit includes a guide hole opened in the voltage detection terminal and a guide protrusion standing on the frame inserted into the guide hole. 5.   The assembled battery according to claim 4, wherein a distal end portion of the guide protrusion is inserted into an insertion hole provided in another frame adjacent to the frame.   The holding means is a guide hole opened in the voltage detection terminal, an embedded hole provided in the frame, and a guide pin that penetrates the guide hole and is inserted into the embedded hole. The assembled battery according to claim 2 or 3.   The assembled battery according to claim 6, wherein a stopper portion that prevents the guide hole of the voltage detection terminal from coming out of the guide pin is provided at the other end of the guide pin.   The holding means is provided on the guide protrusion formed by bending at least one part of the outer periphery of the voltage detection terminal into an L shape and the frame for holding the guide protrusion movably in the thickness direction of the frame. The assembled battery according to claim 2, wherein the assembled battery is a guide groove.   The length of the guide protrusion is such that the voltage detection terminal does not come out of the guide groove even if the voltage detection terminal moves between the frame and another frame adjacent thereto. Item 9. The assembled battery according to Item 8.