JP2012033419A - Power supply device, vehicle using the same, battery cell, and method of manufacturing the battery cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize a bottom surface of a battery cell to facilitate accordance of bottom surfaces when building up a structure in which battery cells are laminated.SOLUTION: A power supply device has coupling means for coupling a plurality of battery cells 1 in a laminated state. Each battery cell 1 has a square exterior package can 12 consisting of a top surface 24, a bottom surface 23, and respective pairs of principal surfaces 21 and side surfaces 22, a cylindrical insulating coating film 20 for coating the principal surfaces 21 and the side surfaces 22 of the exterior package can 12, and an insulating tape 30 with insulation property that coats the bottom surface 23 of the exterior package can 12. A lower end edge of the coating film 20 locates on the principal surfaces 21 and the side surfaces 22 of the exterior package can 12. The insulating tape 30 is bent from the bottom surface 23 of the exterior package can 12 to the principal surfaces 21 and the side surfaces 22, and is fixed to the principal surfaces 21 and the side surfaces 22 of the exterior package can 12 so as to overlap with at least the lower end edge of the coating film 20. The coupling means couples the battery cells 1 in a laminated state in an attitude that respective bottom surfaces 23 of the plurality of battery cells 1 align on the substantially same plane.

Description

  The present invention mainly relates to a power supply device for a large current used for the power supply of a motor that drives a vehicle such as a hybrid vehicle or an electric vehicle, and a vehicle, a battery cell, and a battery cell manufacturing method using the same.

  A vehicle such as an electric vehicle that runs on a motor or a hybrid vehicle that runs on both a motor and an engine is equipped with a power supply device in which a battery cell is housed in an outer case (see, for example, Patent Document 1). This power supply device is a battery block in which a large number of battery cells 1X are connected in series to increase the output voltage, as shown in FIGS. As shown in FIG. 23, each battery cell 1 </ b> X has a square outer can 12 and is provided with positive and negative electrode terminals 13 at the upper end.

  A high-power lithium ion secondary battery is often used for the battery cell 1X. Since the outer can 12 of the lithium ion secondary battery has an intermediate potential, the surface of the battery cell 1X has a high potential, and it is necessary to insulate it from the ground of the outer case. For this reason, insulation measures such as covering the outer can 12 of the battery cell 1X with an insulating cover or an insulating sheet are taken. In addition, the battery cell 1X is waterproof.

  Generally, as shown in FIG. 24, the top surface 24 of the battery cell 1X is covered with a bag-like heat shrinkable sheet 20X so as to expose the electrode terminal 13 on the upper side of the battery cell 1X. Specifically, the heat-shrinkable sheet 20X having a cylindrical opening at the top and the bottom is cut with an appropriate length, and the battery cell 1X is inserted from one opening end as shown in FIG. As shown in b), the heat-shrinkable sheet 20X is heat-shrinked and brought into close contact with the surface of the outer can 12 as shown in FIG. At this time, the heat shrinkable tubes are thermally welded to each other at the bottom surface 23 of the battery cell 1X to close the opening, and the blank portion is cut as necessary to cover the surface of the battery cell 1X with the heat shrinkable tube. It was.

  In this method, as shown in the sectional view of FIG. 24C, the heat shrinkable tube protrudes from the bottom surface 23 of the battery cell 1X, so that the bottom surface 23 of the battery cell 1X becomes uneven. As a result, when a plurality of battery cells 1X are stacked and tightly attached with a bind bar or the like to form a battery stack, the bottom surfaces 23 of the battery cells 1X do not line up on the same plane. For this reason, the top surface 24 of each battery cell 1X does not necessarily coincide, and when the electrode terminals 13 protruded from the top surface 24 of the battery cell 1X are fixed with a bus bar or the like, the plurality of electrode terminals 13 are the same. Since they do not align on a flat surface, there is a problem that the contact surface with the bus bar is not uniform and the contact state is not constant. In addition, in the so-called direct cooling method in which the bottom surface of the battery cell is brought into contact with the cooling plate and cooled from the bottom surface, if the bottom surface of the battery cell is not constant, the contact state with the cooling plate for each battery cell is not constant, The cooling capacity cannot be demonstrated.

JP 2009-170258 A

  The present invention has been made in order to solve the conventional problems as described above. The main object of the present invention is to make the bottom surfaces of the battery cells uniform and to make the bottom surfaces coincide with each other. It is an object of the present invention to provide an easy power supply device, a vehicle, a battery cell, and a battery cell manufacturing method using the same.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, according to the power supply device of the first aspect of the present invention, a plurality of battery cells 1 whose outer shape is a rectangular shape whose thickness is thinner than a width, and the plurality of battery cells The battery cell 1 is a prismatic exterior composed of a top surface 24 and a bottom surface 23, and a pair of main surfaces 21 and side surfaces 22, respectively. A can 12, a cylindrical insulating coating film 20 that covers the main surface 21 and the side surface 22 of the outer can 12, and an insulating insulating tape 30 that covers the bottom surface 23 of the outer can 12, The lower end edge of the covering film 20 is located on the main surface 21 and the side surface 22 of the outer can 12, and the insulating tape 30 is bent from the bottom surface 23 of the outer can 12 to the main surface 21 and the side surface 22. , At least of the covering film 20 It is fixed to the main surface 21 and the side surface 22 of the outer can 12 so as to overlap the edge, and the bottom surfaces 23 of the plurality of battery cells 1 are arranged in a substantially same plane and are stacked by the fastening means. Can be fastened. Thereby, since the bottom surface can be made substantially flat while insulating the surface of the battery cell, the bottom surface can be easily aligned on the same surface when the battery cells are stacked.

  Further, according to the power supply device according to the second aspect, the insulating tape 30 can be folded at the side surface 22 of the outer can 12, and the main surface 21 and the blank portion protruding from the side surface 22 can be folded back. Thereby, since it does not fold in the main surface side which laminates | stacks battery cells by folding in the thickness surface of an exterior can, the advantage which can laminate | stack smoothly is acquired.

  Furthermore, according to the power supply device which concerns on a 3rd side surface, the cooling plate 7 which arrange | positioned the refrigerant | coolant piping 26 arrange | positioned with the bottom face 23 of the said armored can 12 further, and can be provided. Thereby, the battery cell can be cooled from the bottom surface side, and in particular, the battery cell can be efficiently and uniformly cooled by positioning the bottom surface on substantially the same plane.

  Furthermore, according to the power supply device which concerns on a 4th side surface, the said coating film 20 can be used as a heat shrinkable tube. Thereby, a coating film can be easily attached to an exterior can.

  Furthermore, according to the vehicle provided with the power supply device which concerns on a 5th side surface, said power supply device can be provided.

  Furthermore, according to the battery cell according to the sixth aspect, the outer shape of the outer can 12 is a rectangular shape whose thickness is thinner than the width, and the cylindrical shape that covers the main surface 21 and the side surface 22 of the outer can 12. An insulating covering film 20 and an insulating insulating tape 30 covering the bottom surface 23 of the outer can 12, and the lower end edge of the covering film 20 is on the main surface 21 and the side surface 22 of the outer can 12. The insulating tape 30 is bent from the bottom surface 23 to the main surface 21 and the side surface 22 of the outer can 12 and overlaps at least the lower end edge of the covering film 20. 21 and the side 22 can be fixed. Thereby, since the bottom surface can be made substantially flat while insulating the surface of the battery cell, the bottom surface can be easily aligned on the same surface when the battery cells are stacked.

  Furthermore, according to the method for manufacturing the battery cell according to the seventh aspect, the outer can 12 having a rectangular outer shape whose thickness is thinner than the width, and the insulating coating film 20 that covers the outer can 12, The outer can 12 is inserted into the cylindrical covering film 20 into which the outer can 12 can be inserted, and the lower end edge of the covering film 20 is the battery. The step of heat shrinking the covering film 20 so as to be located on the main surface 21 and the side surface 22 of the cell 1 and the insulating insulating tape 30 having an area larger than the bottom surface 23 on the bottom surface 23 of the battery cell 1. Are further folded so as to cover the main surface 21 of the battery cell 1 and to cover the side surface 22 of the battery cell 1 at the blank portion of the insulating tape 30. The margin produced by Folded on the side surface 22 of the serial battery cell 1 may include a step of fixing the insulating tape 30. Thereby, since the bottom surface can be made substantially flat while insulating the surface of the battery cell, the bottom surface can be easily aligned on the same surface when the battery cells are stacked.

1 is a perspective view of a power supply device according to a first embodiment. It is a perspective view which shows the state which removed the upper case from FIG. It is a perspective view which shows the battery block of FIG. FIG. 4 is an exploded perspective view of the battery block of FIG. 3. It is a disassembled perspective view which shows the lamination | stacking state of the battery cells of FIG. It is a perspective view which shows the battery cell of FIG. It is an enlarged view which shows the return | turnback part of the insulating tape of FIG. It is sectional drawing of the insulating tape in the bottom face of the battery cell of FIG. It is a three-plane figure of the battery cell of FIG. It is a schematic diagram which shows the example which the lower end of a coating film protrudes from the bottom face of a battery cell. It is a disassembled perspective view of the battery cell of FIG. It is a perspective view which shows the state which stuck the insulating tape on the bottom face of the battery cell from the state of FIG. It is a perspective view which shows the state bent from the state of FIG. 12 so that both sides of an insulating tape may be along the main surface of a battery cell. It is a perspective view which shows the state which bent the end surface of the insulating tape from the state of FIG. 13, and formed two folding | turning parts. FIG. 15 is a perspective view showing a state where one folded portion of the insulating tape is folded back to the side surface from the state of FIG. 14. It is a schematic diagram which shows the cooling structure of the battery block which concerns on a modification. FIG. 17 is a partially enlarged vertical vertical sectional view of the battery block shown in FIG. 16. FIG. 17 is a vertical cross-sectional view of the battery block shown in FIG. 16. It is a block diagram which shows the example which mounts a battery system in the hybrid vehicle which drive | works with an engine and a motor. It is a block diagram which shows the example which mounts a battery system in the electric vehicle which drive | works only with a motor. It is a top view which shows the power supply device which laminated | stacked the battery cell. It is a side view of the power supply device of FIG. It is a perspective view of the battery cell of FIG. FIG. 24 is a trihedral view showing a state in which the battery cell of FIG. 23 is covered with a conventional coating film. It is a perspective view which shows a mode that the battery cell of FIG. 23 is coat | covered with the conventional coating film. It is a perspective view which shows a mode that a heat-shrink sheet | seat is heat-shrinked from the state of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a power supply apparatus for embodying the technical idea of the present invention, a vehicle using the same, a battery cell, and a method for manufacturing the battery cell. The apparatus, the vehicle using the same, the battery cell, and the battery cell manufacturing method are not specified as follows. In addition, the member shown by the claim is not what specifies the member of embodiment. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the constituent members described in the embodiments are not intended to limit the scope of the present invention only to the description unless otherwise specified. It's just an example. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing. In addition, the contents described in some examples and embodiments may be used in other examples and embodiments.
Example 1

  1 to 20 show a power supply device according to a first embodiment, a vehicle using the same, and a battery cell. In these drawings, FIG. 1 is a perspective view of the battery system 91, FIG. 2 is a perspective view showing a state where the upper case 72 is removed from FIG. 1, FIG. 3 is a perspective view showing the battery block 50 of FIG. 3 is an exploded perspective view of the battery block 50, FIG. 5 is an exploded perspective view showing a stacked state of the battery cells 1 of FIG. 4, FIG. 6 is a perspective view showing the battery cell 1 of FIG. 5, and FIG. FIG. 8 is a sectional view of the insulating tape 30 on the bottom surface 23 of the battery cell 1 of FIG. 7, FIG. 9 is a three-side view of the battery cell 1 of FIG. 6, and FIG. FIG. 11 is an exploded perspective view of the battery cell 1 of FIG. 6, and FIG. 12 is insulated from the state of FIG. 11 to the bottom surface 23 of the battery cell 1. The perspective view which shows the state which affixed the tape 30, FIG. 13 is the state of FIG. FIG. 14 is a perspective view showing a state in which both sides of the insulating tape 30 are bent along the main surface 21 of the battery cell 1, and FIG. 14 shows the two folded portions 32 by bending the end surface of the insulating tape 30 from the state of FIG. 13. 15 is a perspective view showing the formed state, FIG. 15 is a perspective view showing a state in which one folded portion 32 of the insulating tape 30 is folded back to the side surface 22 from the state of FIG. 14, and FIG. 16 is a cooling structure of the battery block 200 according to the modification. 17 is a partially enlarged vertical longitudinal sectional view of the battery block 200 shown in FIG. 16, FIG. 18 is a vertical transverse sectional view of the battery block 200 shown in FIG. 16, and FIG. FIG. 20 is an example of mounting the battery systems 91 and 92 on an electric vehicle that runs only by the motor 93. The block diagram, respectively.

As shown in FIGS. 1 and 2, the external appearance of the battery system 91 is obtained by dividing a box-shaped outer case 70 into two and housing a plurality of battery blocks 50 therein. The exterior case 70 includes a lower case 71, an upper case 72, and end plates 73 connected to both ends of the lower case 71 and the upper case 72. The upper case 72 and the lower case 71 have a flange portion 74 protruding outward, and the flange portion 74 is fixed with a bolt and a nut. In the exterior case 70 of FIGS. 1 and 2, the flange portion 74 is disposed on the side surface of the exterior case 70. In the example of FIG. 2, a total of four battery blocks 50 are stored in the lower case 71, two in the longitudinal direction and two in the horizontal direction. Each battery block 50 is fixed to the lower case 71 with a set screw or the like, and fixed to a fixed position inside the outer case 70. The end surface plate 73 is connected to both ends of the lower case 71 and the upper case 72 and closes both ends of the exterior case 70.
(Battery block 50)

As shown in FIG. 3, each battery block 50 has a substantially box-shaped appearance, and a battery stack 10 in which a large number of battery cells 1 are stacked is sandwiched by end plates 4 from both end surfaces via bind bars 11. Yes. As shown in the exploded perspective view of FIG. 4, the battery stack 10 is configured by stacking a plurality of prismatic battery cells 1 via separators 2. In the example of the battery block 50 in FIG. 4, 18 rectangular battery cells 1 are stacked. The bind bar 11 functions as a fastening means for fastening the battery cell 1. In this example, both ends of the strip-shaped metal plate are bent into bent pieces, and the whole is formed in a U shape. Further, the end plate 4 is provided with a recess at a position for receiving the bent piece of the bind bar 11. By providing a screw hole in the bent piece and the end plate 4, the bind bar 11 is screwed and fixed to the end plate 4.
(Battery cell 1)

As shown in FIG. 5 and FIG. 6, the battery cell 1 is configured by an outer can 12 having an outer shape that is rectangular with a thickness smaller than the width, and closes the top surface 24 of the outer can, that is, the outer can 12. Positive and negative electrode terminals 13 are provided on the sealing plate. The electrode terminals 13 are electrically connected via a bus bar 17 shown in FIG. The outer can of the battery cell can be made of an insulating material such as plastic. In this case, since it is not necessary to insulate the outer can when the battery cells are stacked, the separator can be made of metal.
(Separator 2)

  The battery block 50 has a separator 2 sandwiched between stacked battery cells 1. The battery block 50 can be laminated with the outer can 12 of the battery cell 1 made of metal and insulated by the plastic separator 2. The separator 2 has a shape that can be fitted to the battery cell 1 on both sides, and can be stacked while preventing the positional deviation of the adjacent battery cells 1. The battery block can also be fixed in a laminated state without sandwiching a separator by using an outer can of the battery cell as an insulating material such as plastic.

As shown in FIG. 5, the separator 2 is provided with a cooling gap 53 that allows a cooling gas such as air to pass between the battery cell 1 and the battery cell 1 in order to cool the battery cell 1. Thereby, the battery block 50 has laminated | stacked the several battery cell 1 in the state in which the cooling gap 53 is made. As a cooling mechanism for cooling the battery cells 1 of the battery block 50 by forcibly blowing cooling gas, a forced blowing mechanism 9B is provided as shown in FIG. As shown in FIG. 4, the battery block 50 has a separator 2 sandwiched between stacked battery cells 1. As shown in FIG. 5, the separator 2 has a shape in which a cooling gap 53 is formed between the separator 2 and the battery cell 1. Furthermore, the separator 2 of the figure has connected the battery cell 1 with the fitting structure on both surfaces. Through the separator 2 connected to the battery cell 1 with a fitting structure, the adjacent battery cells 1 are stacked while being prevented from being displaced.
(Battery cell 1)

  The battery cell 1 is a prismatic battery of a lithium ion secondary battery. However, the battery cell may be a secondary battery such as a nickel metal hydride battery or a nickel cadmium battery. The battery cell 1 shown in FIG. 6 made of a square battery is a quadrilateral having a predetermined thickness, and has positive and negative electrode terminals 13 protruding from both ends of the top surface 24, and a safety valve at the center of the top surface 24. The opening is provided. The battery cells 1 to be stacked are connected in series by connecting adjacent positive and negative electrode terminals 13 with a bus bar 17. A battery system in which adjacent battery cells 1 are connected in series can increase the output voltage and increase the output. However, the battery system can also connect adjacent battery cells in parallel.

The surfaces of the battery cell 1 other than the top surface 24 are insulated. Specifically, the surface excluding the top surface 24 and the bottom surface 23 of the battery cell 1 is covered with the coating film 20. The bottom surface 23 is insulated with an insulating tape 30 described later. The top surface 24 is not insulated because the electrode terminals 13 need to be exposed for electrical connection, while the other surfaces are insulated to avoid unintended short circuits. In the configuration in which the battery cell is provided with an insulating property by covering with such an insulating material, it is necessary to pay attention so that the height positions of the battery cells are aligned when the battery cells are stacked. That is, when the battery cells are stacked to form a battery stack, the electrode terminals 13 of the adjacent battery cells are fastened by the bus bar 17, and at this time, the surface of the battery cell is insulated only by the conventional shrink tube. In such a method, the position in the height direction of the electrode terminals between adjacent battery cells is shifted due to a step generated on the bottom surface of the battery cell. As a result, a contact failure between the bus bar and the electrode terminal or the like, or an excessive load is applied to the electrode terminal. In order to solve this problem, in this embodiment, a situation in which a step is formed on the bottom surface 23 of the battery cell is avoided by using an insulating tape in addition to the covering film. This will be described below.
(Coating film 20)

  The main surface 21 of the battery cell 1 is covered with a covering film 20 as shown in FIGS. The covering film 20 is covered as a heat shrinkable tube by heat shrinking the outer surface of the battery cell 1. For such a covering film 20, a resin such as PET preferably having excellent insulating properties and stability can be used. In particular, a shrink tube made of PET resin is inexpensive and preferable as a heat shrinkable tube.

  As shown in FIG. 8 and the like, the covering film 20 is preferably the same length as or shorter than the side surface 22 of the battery cell 1 so as not to protrude from the bottom surface 23 of the battery cell 1 in the vicinity of the bottom surface 23 of the battery cell 1. It forms so that it may become. By doing in this way, the situation where the coating film 20 protrudes to the bottom face 23 side of the battery cell 1 can be avoided. As shown in FIG. 10, when the covering film 20 is formed long and protrudes by t from the bottom surface 23 of the battery cell 1, the battery cell 1 of the battery cell 1 is covered with the insulating tape 30. As a result that the periphery of the bottom surface 23 becomes thicker than the other portions by the protruding amount t or the amount of bending, the bottom surface 23 of the battery cell 1 does not become flat, and irregularities are partially formed. Since such unevenness may cause individual differences for each battery cell, when stacking battery cells, the height or protruding amount of the battery cells cannot be kept constant, and the bottom surface and the ceiling of the battery cell cannot be maintained. When the surface of the battery cell is not aligned, the height of the electrode terminal is not aligned on the top surface of the battery cell, and when the adjacent electrode terminals are connected by the bus bar, the fixed state with the bus bar varies from battery cell to battery cell, resulting in high contact resistance. Become. Further, when connecting to the cooling plate on the bottom surface of the battery cell (FIG. 16 described later), the contact area between the cooling plate and the battery cell bottom surface is different, the cooling capacity varies, and the performance between the battery cells is deteriorated. This is not preferable because individual differences occur.

  Therefore, in order to open such unevenness, the covering film 20 has the bottom surface 23 of the battery cell 1 substantially the same height so as not to protrude from the bottom surface of the battery cell, or the covering film 20 or the battery cell. In consideration of the manufacturing tolerance, the lower end of the covering film 20 is set to be slightly shorter than the bottom surface 23 of the battery cell 1 as shown in FIG. By doing in this way, protrusion of the coating film 20 from the battery cell 1 bottom face 23 can be avoided, and it leads to manufacture of a stable battery cell.

  Note that the fact that the covering film does not protrude from the bottom surface side of the battery cell does not mean that the length of the covering film is necessarily shorter than the height of the battery cell. That is, it is sufficient that the coating film does not protrude from the bottom surface side of the battery cell, and conversely, the coating film slightly protruding on the top surface 24 side of the battery cell is allowed as long as the electrical connection of the electrode terminal 13 is not hindered. .

  That is, on the top surface 24 side, when the battery cells 1 are stacked to form a battery stack, variation in the height position of the electrode terminals 13 between the adjacent battery cells 1 can be suppressed, and when connecting using the bus bar However, the height difference can be reduced, the contact state can be made uniform and the bus bar can be fastened without any trouble, and the reliability of electrical connection can be improved.

  On the other hand, in order to avoid reaching the bottom surface of the battery cell, in other words, when the covering film is intentionally shortened at the lower end and the main surface of the battery cell is exposed near the bottom surface, this portion is not intended unless it is covered. Conduction occurs. Therefore, the insulating tape 30 that covers the bottom surface 23 of the battery cell is folded to cover such an exposed portion. As a result, a portion where the covering film 20 and the insulating tape 30 overlap is generated along the periphery of the battery cell 1. In the three views of FIG. 9, the overlapping portion is indicated by OW.

  Furthermore, as a result of covering the bottom surface 23 and its peripheral region with the planar insulating tape 30, it is necessary to fold back the edge. Such a folded portion is not the main surface 21 side of the battery cell 1, but the side surface 22 It is arranged to be located on the side. An example of such folding will be described with reference to FIGS. First, as shown in FIG. 11, the outer can 12 is inserted into a cylindrical covering film 20 into which the outer can 12 can be inserted. Here, the lower end of the coating film 20 is aligned with the main surface 21 and the side surface 22 of the battery cell 1 at a position that does not protrude from the lower end edge, and is thermally welded. Next, an insulating insulating tape 30 having a larger area than the bottom surface is covered on the bottom surface 23 of the battery cell 1 (FIG. 12). Further, as shown in FIG. 13, the insulating tape 30 is bent so as to cover the main surface 21 of the battery cell 1 at the blank portion. At this time, the overlapping portion is formed so that the tip of the insulating tape 30 overlaps the coating film 20 and the edge. Further, the insulating tape 30 is bent so as to cover the side surface 22 of the battery cell 1. As shown in FIG. 14, a blank portion generated by these bends is a folded portion 32. Two folded portions 32 are formed on the edge of the insulating tape 30 on the left and right sides, respectively, in a right triangle shape. Then, the folded portion 32 is folded back to the side surface 22 of the battery cell 1, and the insulating tape 30 is adhered (FIGS. 15 and 7). At this time, the folded portions 32 are bonded to each other with, for example, an adhesive. However, the folded portion does not necessarily have to be bonded, and may simply be bent. Specifically, the folded portion 32 is positioned between the side surface of the separator 2 and the side surface 22 of the battery cell 1 and is closely attached. As described above, since the bottom surface can be made substantially flat while insulating the surface of the battery cell, the bottom surface can be easily aligned on the same surface when the battery cells are stacked.

It should be noted that the above folding method is an example, and other folding methods can be used as appropriate. For example, in the above example, the insulating tape 30 is bent in a concave shape first on the main surface 21 side, and then the side surface 22 side is bent, but after the side surface side is bent first, the main surface side is You may make it bend. Also in this case, the folding of the blank generated at the intersecting portion is positioned not on the main surface side but on the side surface side. Further, the shape of the insulating tape and the method of bonding the folded portion are examples, and it goes without saying that other shapes and bonding methods can be used as appropriate. For example, the shape of the insulating tape may be such that the bonded portions remain in the folded portions so that the folded portions can be bonded together without an adhesive or the like. Furthermore, by devising the shape of the insulating tape, the overlapping portion of the folded portion can be made thin, or the surface where the folded portion is folded can be made uniform.
(Insulating tape 30)

  The insulating tape 30 is made of a resin having an insulating property, and an adhesive material is applied to one surface so that it can be bonded. As such an insulating tape 30, a polyimide tape (trade name Kapton tape) can be suitably used. Alternatively, a silicon resin sheet, a plastic sheet filled with a filler having excellent heat conduction, mica, or the like can be used. Further, the surplus portion of the insulating tape 30 is folded back at the side 22 portion of the battery cell 1. By doing in this way, these surfaces can be maintained substantially flat, without generating unnecessary unevenness on the bottom surface 23 or main surface 21 side of the battery cell 1, and reliability when stacking a plurality of battery cells 1 is achieved. Can be improved.

  At this time, the bottom surface 23 of the battery cell 1 is not provided with irregularities and is maintained flat. In this way, when stacking a plurality of battery cells 1, it becomes easy to match the bottom surface 23 so as to be substantially the same surface. As a result, the electrode terminals 13 are also on the same surface on the top surface of the battery stack 10. As a result, the connection by the bus bar 17 and the like can be performed stably, leading to an improvement in reliability.

  In addition, as shown in the modification of FIG. 16, in the direct cooling method in which the bottom surface 23 of the battery cell 1 is brought into contact with the cooling plate 7 for cooling, the contact surface between the battery cell 1 and the cooling plate 7 is a flat surface. Therefore, the thermal coupling can be ensured and the cooling capacity can be exhibited. In particular, by preventing the formation of irregularities due to the folding back of the insulating tape 30 from occurring on the bottom surface 23, individual differences and variations in the connection state with the cooling plate 7 for each battery cell are reduced, and the cooling capacity between the battery cells. There is also an advantage that the occurrence of variations in the above can be suppressed. Further, by not providing an extra unevenness on the main surface 21 side of the battery cell 1, it becomes possible to stably stack the battery cells, and there is also an advantage that the fastening by the bind bar can be surely performed.

  As described above, a battery in which battery cells are stacked together by using a covering film that covers the side surfaces of the battery cells and an insulating tape that covers the bottom surface and positioning the folded surface of the insulating tape on the side surfaces of the battery cells. The reliability of the laminate can be increased. Temporarily, in the insulation with only the insulating tape, the folded portion becomes large and the processing becomes troublesome. However, most of the main surface 21 and the side surface 22 of the battery cell are covered with a covering film in advance, and the remaining bottom surface 23 and The folded portion 32 can be made smaller by covering only a part of the main surface 21 and the side surface 22 close to the bottom surface 23 with the insulating tape 30. In addition, as compared to a configuration in which the whole is covered only with the insulating tape, the amount of the insulating tape used can be reduced, so that the effect of reducing the member cost and the manufacturing cost can be expected.

In addition to the configuration in which the insulating tape is applied as a tape, the insulating tape is configured to insulate the bottom surface of the battery cell by applying a liquid insulating material or spraying a gaseous insulating material. You can also.
(Modification)

  Moreover, in the example of FIG. 1 etc. which were demonstrated above, although the air-cooling type which forcedly ventilates cooling air with a fan and cooled the battery cell 1 was employ | adopted, it is not restricted to this structure, It cools directly using a refrigerant | coolant etc. Alternatively, a so-called direct cooling system may be employed. Such an example will be described as a modification with reference to FIGS.

The power supply device that constitutes the battery system 92 shown in FIG. 16 is arranged in a thermally coupled state to the battery stack 10 in which the battery cells 1 composed of a plurality of rectangular batteries are stacked, and the battery cells 1 that constitute the battery stack 10. And a cooling mechanism 9 for cooling the cooling plate 7. The cooling mechanism 9 can effectively cool the battery stack 10 directly by bringing the battery stack 10 into contact with the cooling plate 7. Further, not only the battery stack, but also, for example, each member disposed on the end face of the battery stack 10 can be cooled together, which is excellent in terms of reliability.
(Cooling plate 7)

  The cooling plate 7 is a radiator for conducting heat of the battery cell 1 to dissipate it to the outside. In the example shown in the figure, a refrigerant pipe is provided. As shown in the cross-sectional view of FIG. 17, the cooling plate 7 has a closed chamber as an inside, and as a heat exchanger in the closed chamber, a coolant pipe 26 such as copper or aluminum that circulates a liquefied coolant that is a coolant. Built-in cooling pipe. The cooling pipe is fixed so as to be in close contact with the upper surface plate of the cooling plate 7 to cool the upper surface plate, and a heat insulating material is disposed between the cooling plate and the bottom plate to insulate the space from the bottom plate. Further, the cooling plate 7 can be composed of only a metal plate in addition to the cooling function by the refrigerant. For example, it is made into the shape excellent in heat dissipation and heat transfer property, such as a metal body provided with a radiation fin. Or you may utilize not only metal but the heat-transfer sheet | seat which has insulation.

  The cooling plate 7 constitutes battery cooling means for cooling the battery stack 10 placed on the upper surface. In this example, as shown in the cross-sectional view of FIG. 17, a refrigerant pipe 26 for circulating the refrigerant is provided inside the cooling plate 7. The coolant is supplied from the cooling mechanism 9 shown in FIG. 16 to the refrigerant pipe 26 to cool the cooling plate 7. The cooling plate 7 can cool the cooling plate 7 more efficiently by using the cooling liquid supplied from the cooling mechanism 9 as a refrigerant that cools the cooling plate 7 with heat of vaporization that evaporates inside the refrigerant pipe 26.

  In order to cool the battery cell 1, the cooling plate 7 is fixed in a thermally coupled state to the bottom surface 23 that is the outer peripheral surface of each battery cell 1 constituting the battery block 200. In a battery system in which adjacent battery cells are connected in series, there is a potential difference between adjacent battery cells. Therefore, if a battery cell composed of a metal outer can is electrically connected to the cooling plate as it is, a short circuit occurs and a large short current flows. In contrast, the battery cell 1 in which the bottom surface of the outer can is covered with the insulating tape 30 as described above can avoid such a short circuit and can be thermally coupled to the cooling plate 7 in an insulated state. Moreover, it is preferable to comprise the insulating tape 30 by the insulating member excellent in thermal conductivity so that it can be in a thermal coupling state while being in an insulating state with the cooling plate 7. A polyimide tape or the like is suitable as a material for obtaining such characteristics as described above. Further, a heat conductive paste such as silicon oil may be applied between the insulating tape 30 and the cooling plate 7 so as to conduct heat more efficiently.

  Furthermore, the cooling plate 7 also functions as a soaking means for equalizing the temperatures of the plurality of battery cells 1. That is, the heat energy absorbed by the cooling plate 7 from the battery cell 1 is adjusted to efficiently cool the battery cell whose temperature is increased, for example, the battery cell in the central portion, and the battery where the temperature is decreased, such as the battery at both ends. Reduce the temperature difference between the battery cells by reducing the cooling of the cells. Thereby, the temperature unevenness of the battery cells can be reduced, and a situation in which deterioration of some of the battery cells proceeds and overcharge and overdischarge can be avoided.

In the example of FIG. 16, an example in which the cooling plate 7 is disposed on the bottom surface 23 of the battery block 200 is shown, but the configuration is not limited to this. For example, the cooling plate can be disposed on the side surface of the battery cell. In the present invention, since the folded portion of the insulating tape can be reduced, cooling is not hindered even when the cooling plate is disposed on the side surface of the battery cell. Moreover, in the Example of this invention, although the folding | turning part is turned up to the surface which comprises thickness with an exterior can, it can change suitably with the structure of a power supply device. For example, the folded portion may be folded to the surface constituting the width with an outer can.
(Vehicle using power supply)

  Next, a vehicle equipped with a power supply device using the above battery cells will be described with reference to FIGS. FIG. 19 shows an example of a hybrid vehicle HV that is equipped with a battery system for a vehicle and that runs on both the engine and the motor. The hybrid vehicle shown in this figure includes an engine 96 and a running motor 93 for running the vehicle, battery systems 91 and 92 for supplying electric power to the motor 93, and a generator 94 for charging the batteries of the battery systems 91 and 92. I have. The battery systems 91 and 92 are connected to a motor 93 and a generator 94 via a DC / AC inverter 95. The hybrid vehicle runs on both the motor 93 and the engine 96 while charging and discharging the batteries of the battery systems 91 and 92. The motor 93 is driven to drive the vehicle when the engine efficiency is low, for example, during acceleration or low-speed driving. The motor 93 is driven by power supplied from the battery systems 91 and 92. The generator 94 is driven by the engine 96 or is driven by regenerative braking when the vehicle is braked, and charges the batteries of the battery systems 91 and 92.

  Furthermore, FIG. 20 shows an example of an electric vehicle EV that is a vehicle equipped with a battery system for a vehicle and runs only by a motor. The electric vehicle shown in this figure includes a traveling motor 93 for traveling the vehicle, battery systems 91 and 92 for supplying electric power to the motor 93, and a generator 94 for charging the batteries of the battery systems 91 and 92. I have. The battery systems 91 and 92 are connected to a motor 93 and a generator 94 via a DC / AC inverter 95. The motor 93 is driven by power supplied from the battery systems 91 and 92. The generator 94 is driven by energy used when regenerative braking of the vehicle, and charges the batteries of the battery systems 91 and 92.

  A power supply apparatus according to the present invention, a vehicle using the same, a battery cell, and a battery cell manufacturing method include a plug-in hybrid electric vehicle, a hybrid electric vehicle, an electric vehicle, and the like that can switch between an EV traveling mode and an HEV traveling mode. It can be suitably used as a power supply device.

DESCRIPTION OF SYMBOLS 1, 1X ... Battery cell 2 ... Separator 4 ... End plate 7 ... Cooling plate 9 ... Cooling mechanism 9B ... Forced ventilation mechanism 10 ... Battery laminated body 11 ... Bind bar 12 ... Exterior can 13 ... Electrode terminal 17 ... Bus bar 20 ... Covering film 20X ... heat-shrinkable sheet 21 ... main surface 22 ... side surface 23 ... bottom surface 24 ... top surface 26 ... refrigerant pipe 30 ... insulating tape 32 ... folded portion 50 ... battery block 53 ... cooling gap 70 ... outer case 71 ... lower case 72 ... upper Case 73 ... End face plate 74 ... Eaves 91, 92 ... Battery system 93 ... Motor 94 ... Generator 95 ... Inverter 96 ... Engine 200 ... Battery block HV, EV ... Vehicle OW ... Overlapping portion t ... Projection amount

Claims (7)

A plurality of battery cells (1) whose outer shape is a square with a thickness smaller than the width,
Fastening means for fastening the plurality of battery cells (1) in a stacked state;
A power supply device comprising:
Each of the battery cells (1) is
A top surface (24) and a bottom surface (23), and a rectangular outer can (12) composed of a pair of main surfaces (21) and side surfaces (22);
A cylindrical insulating covering film (20) covering the main surface (21) and the side surface (22) of the outer can (12);
An insulating insulating tape (30) covering the bottom surface (23) of the outer can (12);
With
The lower end edge of the covering film (20) is located on the main surface (21) and side surface (22) of the outer can (12),
The insulating tape (30) is bent from the bottom surface (23) of the outer can (12) to the main surface (21) and the side surface (22), and overlaps at least the lower end edge of the covering film (20). It is fixed to the main surface (21) and side surface (22) of the outer can (12),
The power supply device, wherein the bottom surfaces (23) of the plurality of battery cells (1) are fastened in a stacked state by the fastening means in a posture in which they are arranged on substantially the same plane. The power supply device according to claim 1,
In the side surface (22) of the outer can (12), the insulating tape (30) is generated by bending, and is folded back from the main surface (21) and the blank portion protruding from the side surface (22). apparatus. The power supply device according to claim 1, further comprising:
A power supply apparatus comprising: a cooling plate (7) provided with a refrigerant pipe (26) arranged in a thermally coupled state with a bottom surface (23) of the outer can (12). The power supply device according to any one of claims 1 to 3,
The power supply apparatus, wherein the covering film (20) is a heat shrinkable tube.   A vehicle comprising the power supply device according to claim 1. An outer can (12) whose outer shape is a square with a thickness smaller than the width;
A cylindrical insulating covering film (20) covering the main surface (21) and the side surface (22) of the outer can (12);
An insulating insulating tape (30) covering the bottom surface (23) of the outer can (12);
With
The lower end edge of the covering film (20) is located on the main surface (21) and side surface (22) of the outer can (12),
The insulating tape (30) is bent from the bottom surface (23) of the outer can (12) to the main surface (21) and the side surface (22), and overlaps at least the lower end edge of the covering film (20). A battery cell characterized by being fixed to a main surface (21) and a side surface (22) of the outer can (12). An outer can (12) whose outer shape is a square with a thickness smaller than the width;
An insulating covering film (20) for covering the outer can (12);
A method for producing a battery cell comprising:
The outer can (12) is inserted into the cylindrical covering film (20) into which the outer can (12) can be inserted, and the lower end edge of the covering film (20) is connected to the battery cell (1). Heat shrinking the covering film (20) so as to be located on the main surface (21) and the side surface (22) of
The bottom surface (23) of the battery cell (1) is covered with an insulating insulating tape (30) having an area larger than that of the bottom surface (23), and the battery is covered with a blank portion of the insulating tape (30). Bending to cover the main surface (21) of the cell (1) and to cover the side surface (22) of the battery cell (1) Folding back to the side surface (22) of (1) and fixing the insulating tape (30);
The manufacturing method of the battery cell characterized by including.

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