JP6231918B2 - Battery system and manufacturing method thereof - Google Patents

Description

  The present invention relates to a battery system in which a plurality of battery cells are stacked to form a battery stack block, and both ends of the battery stack block are pressed and fixed by end plates, and a method for manufacturing the battery system.

  A large number of battery cells are stacked to form a battery stack block, a pair of end plates are arranged on both end faces of the battery stack block, both end plates are connected by a binding tool, and the stacked battery cells are pressed. A battery system to be fixed to the battery has been developed. (See Patent Document 1)

  This battery system fixes a battery cell in a pressed state with a pair of end plates. The end plates are arranged on both end faces of the battery stack block in which a plurality of battery cells are stacked, and are connected to a binding tool in a state in which the battery stack block is pressed to fix the battery stack block in a pressurized state. Further, adjacent battery cells are connected in series or in parallel with a metal plate bus bar fixed to the positive and negative electrode terminals.

JP 2011-60623 A

  By the way, in the battery system, due to the dimensional error of the battery cells generated in the manufacturing process, the relative positions of the electrode terminals of the adjacent battery cells may be shifted in a state where they are stacked on each other. Adjacent battery cells are fixed by welding or screwing a metal plate bus bar to the positive and negative electrode terminals, so that it is difficult to reliably and securely fix the bus bar when the relative position is shifted. For example, when battery cells with dimensional errors in the height between the terminal surface on which the electrode terminal is provided and the bottom surface on the opposite side are stacked on the same plane, the terminal surfaces of adjacent battery cells are the same It is not placed on a plane. In battery stack blocks in which the terminal surfaces of adjacent battery cells cannot be arranged on the same plane, the electrode terminals of adjacent battery cells are relatively displaced up and down. If a bus bar made of a thick metal plate that is not elastically deformed is fixed to the electrode terminal on the terminal surface that is displaced up and down, excessive stress acts on the electrode terminal, causing damage to the battery cell.

  The above adverse effects can be solved by, for example, a structure in which the terminal surfaces of the respective battery cells are arranged on the same plane. This battery system can be realized by providing a fitting part for arranging the terminal surfaces on the same plane in the binding tool and arranging an elastic body on the bottom surface of each battery cell. A fitting part is arrange | positioned on the terminal surface of each battery cell, presses the terminal surface of each battery cell against this, and arrange | positions on the same plane. The terminal surfaces of the battery cells are arranged on the same plane by being pressed against the inner surface of the fitting portion via an insulating material or directly. An elastic body is arrange | positioned at the bottom face of each battery cell, and presses each battery cell toward a fitting part elastically.

  In the battery system of FIG. 13, an elastic plate 909 is disposed on the bottom surface of the battery stack block 902. The elastic plate 909 is provided with an elastic pressing portion 919 that elastically presses each battery cell 901 from the bottom surface toward the terminal surface 901A. In this battery system, each battery cell 901 is elastically pushed up independently by each elastic pressing part 919 in the figure. Each battery cell 901 presses the terminal surface 901A against the lower surface of the fitting portion 904A of the binding tool 904 via an insulating spacer 905 made of an insulating material. Each battery cell 901 pressed against the inner surface of the fitting portion 904A via the insulating spacer 905 is stacked with the terminal surface 901A arranged on the same plane. In this battery system, the elastic pressing portion 919 elastically pushes up the battery cell 901, the terminal surface 901A of the battery cell 901 is disposed on the inner surface of the fitting portion 904A of the binding tool 904, and the terminal surface of each battery cell 901 is arranged. 901A is arranged on the same plane.

  The above battery system arrange | positions the elastic plate so that each battery cell may be elastically pressed by an elastic press part. The elastic pressing portion is pressed against the bottom surface of each battery cell. The elastic plate elastically presses the battery cell in a state where the elastic pressing portion is crushed and elastically deformed. In order to press the elastic plate against the bottom surface of the battery cell, the battery system of FIG. 13 is provided with a locking portion 904B that presses the elastic plate 909 against the battery stack block 902 on the binding tool 904. The locking portion 904B is below the elastic plate 909, and the elastic plate 909 is disposed on the bottom surface of the battery stack block 902 in a state where the elastic pressing portion 919 is crushed. In the battery system described above, the battery stack block 902 and the elastic plate 909 are inserted between the fitting portion 904A and the locking portion 904B of the binding tool 904 in a state where the elastic pressing portion 919 of the elastic plate 909 is crushed, The binding tool 904 is fixed to the end plate. In order to put the battery stack block and the elastic plate between the fitting part and the engaging part of the binding tool in a state where the elastic pressing part is crushed, press the terminal surface of the battery stack block with a jig and face the elastic plate toward the elastic plate. It is necessary to hold the elastic pressing portion in a crushed state and insert the battery stack block and the elastic plate between the fitting portion and the locking portion in this state. In a state where the battery stack block and the elastic plate are inserted between the fitting portion and the locking portion of the binding tool, the fitting portion and the locking portion cover both sides of the battery cell. Therefore, in order to crush the elastic pressing portion, the battery stack block cannot be pressed at the position covered by the fitting portion with the jig. This is because the jig interferes with insertion of the battery laminated block inside the fitting portion. Therefore, in this battery system, it is necessary to insert the battery stack block inside the fitting portion by pressing the battery stack inside the position where the fitting portion of the binding tool is inserted and crushing the elastic pressing portion. is there. However, when the battery stack is inserted inside the mating part by pressing the inner side from the position where it is inserted into the mating part and the battery stack is inserted inside the mating part, the elastic pressing part is held in a crushed state and the battery stack is fitted. There is a drawback that it is difficult to insert smoothly inside the part. This is because the pressed position of the battery stack block cannot be accurately positioned because the battery stack block is pressed at a position where it is not inserted into the fitting portion. In particular, the battery system in which the horizontal portion of the insulating spacer is disposed at both ends of the terminal surface and the horizontal portion of the insulating spacer is disposed between the battery stack block and the fitting portion is an insulating material to be inserted inside the fitting portion. Since the horizontal portion of the spacer cannot be pressed, there is a drawback that it is difficult to insert the battery stack block inside the fitting portion.

  The present invention was developed for the purpose of eliminating the above-described drawbacks. An important object of the present invention is to hold the elastic pressing portion of the elastic plate in a crushed state so that the battery stack block and the elastic plate It is intended to provide a battery system and a method of manufacturing the battery system that can be easily and efficiently assembled by inserting the cable into the fitting portion and the engaging portion of the binding tool.

Means for Solving the Problems and Effects of the Invention

  In the battery system of the present invention, a bus bar 14 is formed by stacking a plurality of battery cells 1 each having a positive and negative electrode terminal 13 on a terminal surface 1A in the thickness direction and fixing the battery cells 1 to the electrode terminals 13 of each battery cell 1. Are arranged on the bottom surface 1B located on the opposite side of the terminal surface 1A of the battery cell 1, and each battery cell 1 is connected to the terminal from the bottom surface 1B. An elastic plate 9 having an elastic pressing portion 19 that elastically presses toward the surface 1A, and a pair of end plates 3 at both ends of the battery stack block 2 that pressurize and fix the battery cells 1 in the stacking direction; And a binding tool 4 for connecting the pair of end plates 3 and fixing the plurality of battery cells 1 in the pressurizing state in the stacking direction. The binding tool 4 includes a fitting portion 4A that is disposed outside the terminal surface 1A of the battery stack 2 and a locking portion 4B that is disposed outside the elastic plate 9. In the battery system, the battery stack 2 and the elastic plate 9 are arranged between the fitting part 4A and the locking part 4B of the binding tool 4, and the elastic pressing part 19 is elastically deformed, whereby each elastic pressing part 19 is provided. Each of the battery cells 1 is elastically pressed toward the fitting portion 4A by the elastic restoring force of the battery stack block 2 or the battery stack block 2 or A notch 4a for guiding a jig that presses the elastic plate 9 is provided.

  In the above battery system, the elastic pressing portion of the elastic plate is held in a crushed state, and the battery stack block and the elastic plate are smoothly inserted between the fitting portion and the locking portion of the binding tool, There is a feature that can be assembled efficiently. This is because the battery system described above can hold the elastic pressing portion of the elastic plate in a crushed state by providing a notch in the fitting portion or the locking portion and a jig guided by the notch. In particular, since the battery system described above is provided with a notch in the fitting portion or the locking portion, the battery stack block and the elastic plate inserted inside the fitting portion and the locking portion are pressed, and the elastic pressing portion is There exists the characteristic which hold | maintains in a crushed state and can insert smoothly inside a fitting part and a latching | locking part.

  In the battery system of the present invention, the notches 4 a can be provided at both ends of the binding tool 4. In this battery system, the battery stack block and elastic plate are pressed at both ends with a jig guided by notches provided at both ends, and the battery stack block is inserted inside the fitting portion and the locking portion. it can. By pressing both ends of the battery stack block and the elastic plate with jigs, the elastic plate is pressed in a balanced manner at both ends and can be smoothly inserted inside the fitting portion and the locking portion.

In the battery system of the present invention, a side plate 4X disposed on the side surface of the battery stack 2 in the binding tool 4, and L disposed on the outer end surface of the end plate 3 connected to both ends of the side plate 4X. 4C can be provided, the fitting part 4A and the locking part 4B can be provided on both side edges of the side plate 4X, and the notches 4a can be provided at both ends of the fitting part 4A and the locking part 4B. .
In the above battery system, the L-shaped fixing portion can be arranged outside the end plate, and the binding tool can be securely and firmly fixed to the end plate. In addition, notches that guide the jig for pressing the battery stack block and the elastic plate to crush the elastic pressing part are provided at both ends of the fitting part and the locking part. It also realizes the feature that the stress concentrated on the part can be dispersed to prevent the side plate from being damaged.

The battery system manufacturing method of the present invention is a bus bar in which a plurality of battery cells 1 having positive and negative electrode terminals 13 provided on a terminal surface 1A are stacked in the thickness direction and fixed to the electrode terminals of each battery cell. Are arranged on the bottom surface 1B of the battery stack block 2, and each battery cell 1 is elastically pressed from the bottom surface 1B toward the terminal surface 1A. An elastic plate 9 having an elastic pressing portion 19, a pair of end plates 3 that are at both ends of the battery stack 2 and pressurize and fix the battery cell 1 in the stacking direction, and a pair of end plates 3 are connected. A binding device 4 that fixes the plurality of battery cells 1 in a pressurized state in the stacking direction, and the binding device 4 includes a fitting portion 4A that is disposed outside the terminal surface 1A of the battery stack block 2; Of elastic plate 9 The battery stacking block 2 and the elastic plate 9 are arranged between the fitting part 4A and the engaging part 4B of the binding device 4, and the elastic pressing part 19 is provided with the engaging part 4B. A method of manufacturing a battery system that is elastically deformed and elastically presses each battery cell 1 toward the fitting portion 4 </ b> A by the elastic restoring force of each elastic pressing portion 19. A cutout 4a for guiding a jig that presses the battery stack block 2 or the elastic plate 9 is provided in either or both of the joining portion 4A and the locking portion 4B, and end plates 3 are disposed at both ends of the battery stack block 2. In the state where each battery cell 1 is pressed in the stacking direction with the end plate 3, the jig is guided by the notch 4 a and the elastic pressing portion 19 of the elastic plate 9 is held in a state of elastic deformation, Fitting part 4 of binding tool 4 And by placing a cell stack block 2 and the elastic plate 9 between the engaging portion 4B, and guided to the cutout 4a of the jig, securing the closure 4 to the end plate 3 in this state.

  In the above manufacturing method, the battery pressing block and the elastic plate are smoothly placed inside the fitting portion and the locking portion by holding the elastic pressing portion of the elastic plate in a state of being crushed with a jig guided by the notch. It has the feature that it can be inserted and assembled easily and efficiently. That is, the above manufacturing method is modified so that the fitting portion and the locking portion are notched, and the elastic pressing portion is crushed by a jig guided by the notch, and the battery stack block and the elastic plate This is because it can be inserted between the locking portion and the fitting portion. In particular, in the above manufacturing method, since the notch is provided in the fitting part and the locking part of the binding tool, both sides of the battery stack block and the elastic plate inserted inside the fitting part and the locking part are jigged. It has a feature that it can be pressed and smoothly inserted inside the fitting portion and the locking portion.

It is a perspective view of the battery system concerning one embodiment of the present invention. It is a disassembled perspective view of the battery system shown in FIG. FIG. 2 is a vertical cross-sectional view of the battery system shown in FIG. 1. FIG. 2 is an exploded plan view of the battery system shown in FIG. 1. FIG. 2 is an exploded bottom view of the battery system shown in FIG. 1. It is a disassembled perspective view which shows the laminated structure of a battery cell and a spacer. It is a vertical cross-sectional view of a battery system according to another embodiment of the present invention. It is a perspective view of an elastic plate. It is an expansion perspective view of a binding tool. It is a schematic sectional drawing which shows an example of the assembly process of a battery system. It is a schematic sectional drawing which shows another example of the assembly process of a battery system. It is a schematic sectional drawing which shows another example of the assembly process of a battery system. It is a schematic sectional drawing which shows the assembly process of the conventional battery system.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a battery system and its manufacturing method for embodying the technical idea of the present invention, and the present invention specifies the battery system and its manufacturing method as follows. do not do. Furthermore, this specification does not limit the members shown in the claims to the members of the embodiments.

  A battery system 100 shown in FIGS. 1 to 5 includes a battery stack block 2 in which a plurality of battery cells 1 are stacked, and a pair of end plates 3 disposed at both ends of the battery stack block 2 in the stacking direction. The elastic plate 9 disposed under the battery stack block 2 and both ends thereof are connected to the pair of end plates 3 to fix the battery cells 1 of the battery stack block 2 in a pressurized state in the stacking direction, And a binding tool 4 in which an elastic plate 9 is disposed under the battery stack block 2.

  As shown in FIG. 6, the battery cell 1 is a rectangular battery having a rectangular shape with a flat surface 1 </ b> C that is wider and wider than the thickness, and is stacked in the thickness direction to form a battery stack block 2. The battery cell 1 is a non-aqueous electrolyte battery using a battery case 10 as a metal case. The battery cell 1 which is a non-aqueous electrolyte battery is a lithium ion secondary battery. However, the battery cell may be any other secondary battery such as a nickel metal hydride battery or a nickel cadmium battery. The battery cell 1 shown in the figure is a battery having a rectangular outer shape, and is laminated so as to face both sides to form a battery laminated block 2.

  In the battery cell 1, an electrode body (not shown) is accommodated in a metal battery case 10 having a rectangular outer shape of the flat surface 1 </ b> C and filled with an electrolytic solution. The battery case 10 made of a metal case can be made of aluminum or an aluminum alloy. The battery case 10 includes an outer can 10A in which a metal plate is pressed into a cylindrical shape that closes the bottom, and a sealing plate 10B that airtightly closes an opening of the outer can 10A. The sealing plate 10B is a planar metal plate, and its outer shape is the inner shape of the opening of the outer can 10A. The sealing plate 10B is inserted inside the opening of the outer can 10A without a gap, and is welded to the outer can 10A by irradiating a laser between the inner surface of the outer can 10A.

  The battery cell 1 has positive and negative electrode terminals 13 fixed to both ends of the sealing plate 10B, the sealing plate 10B serves as a terminal surface 1A, the surface opposite to the terminal surface 1A, and the lower surface of the battery cell 1 in FIG. 1B. Further, the sealing plate 10B is provided with a gas discharge port 12 in the middle of the positive and negative electrode terminals 13. A discharge valve 11 that opens at a predetermined internal pressure is provided inside the gas discharge port 12. The battery stack block 2 stacks a plurality of battery cells 1 in such a posture that the terminal surface 1A is positioned on the same plane.

  In the battery stack 2, a metal plate bus bar 14 is fixed to the positive and negative electrode terminals 13 of adjacent battery cells 1, and the battery cells 1 are connected in series with each other by the bus bar 14. However, the battery stack can also connect battery cells in series and / or in parallel. A battery system in which adjacent battery cells are connected in series with each other can increase output voltage by increasing output voltage, and can connect adjacent battery cells in parallel to increase charge / discharge current. In the battery stack block 2 of FIG. 6, a linear bus bar 14 </ b> A and an L-shaped bus bar 14 </ b> B are welded and fixed to the electrode terminals 13 of the battery cell 1. The straight bus bar 14A and the L-shaped bus bar 14B are stacked at the tip, provided with a through hole 14a in the laminated portion, a set screw 15 is inserted into the through hole 14a, and a nut 16 is screwed into the set screw 15. The bus bars 14 are fixed to each other.

  The battery stack block 2 shown in FIG. 6 is stacked with an insulating spacer 5 sandwiched between a plurality of battery cells 1. In the illustrated battery stack block 2, adjacent battery cells 1 are arranged in opposite directions, and adjacent electrode terminals 13 on both sides thereof are connected by a bus bar 14 to connect two adjacent battery cells 1 in series. All battery cells 1 are connected in series. However, the present invention does not specify the number of battery cells constituting the battery stack and the connection state thereof.

  The insulating spacer 5 is sandwiched between adjacent battery cells 1 to insulate the battery cells 1 having a potential difference. The insulating spacer 5 shown in the figure is manufactured by molding an insulating plastic. The insulating spacer 5 is disposed so as to be in contact with the flat surface 1 </ b> C of the adjacent battery cell 1, and the plate portion 20 sandwiched between the battery cells 1 and the horizontal portion disposed outside the outer peripheral surface of the battery cell 1. 22 are integrally formed of plastic. The insulating spacers 5 can be stacked so that the battery cells 1 are arranged in a fixed position by placing the battery cells 1 inside the horizontal portion 22 so that the battery cells 1 are not displaced.

  As described above, in the battery cell 1 that is insulated and stacked by the insulating spacer 5, the outer can 10A can be made of a metal such as aluminum. However, the battery laminated block does not necessarily need to interpose an insulating spacer between the battery cells. For example, by insulating the battery cells adjacent to each other by molding the battery cell outer can with an insulating material, or covering the outer periphery of the battery cell outer can with an insulating sheet or insulating paint, etc. This is because no spacer is required.

  Further, the insulating spacer 5 shown in FIG. 6 has a cooling gap 26 that allows a cooling gas such as air to pass through the plate portion 20 sandwiched between the battery cells 1 in order to effectively cool the battery cells 1. Is provided. The plate portion 20 of the insulating spacer 5 shown in FIG. 6 is provided with grooves 25 extending to both side edges on the surface facing the battery cell 1, and a cooling gap 26 is provided between the battery cell 1. In the insulating spacer 5 shown in the drawing, a plurality of grooves 25 are provided in parallel with each other at a predetermined interval. The plate portion 20 shown in the figure has grooves 25 on both surfaces, and a cooling gap 26 is provided between the battery cell 1 and the insulating spacer 5 adjacent to each other. This structure has an advantage that the battery cells 1 on both sides can be effectively cooled by the cooling gaps 26 formed on both sides of the plate portion 20. However, the insulating spacer can be provided with a groove only on one side, and a cooling gap can be provided between the battery cell and the insulating spacer. The cooling gap 26 in the figure is provided in the horizontal direction so as to open to the left and right of the battery stack block 2. The air forcedly blown into the cooling gap 26 directly and efficiently cools the outer can 10 </ b> A of the battery cell 1. This structure is characterized in that the battery cell 1 can be efficiently cooled while effectively preventing thermal runaway of the battery cell 1.

  The insulating spacer 5 described above can cool the battery cell 1 by providing a cooling gap 26 between the battery cell 1 and forcibly blowing a cooling gas such as cooling air into the cooling gap 26. However, it is not always necessary for the insulating spacer to provide a cooling gap with the battery cell. As shown in FIG. 7, the elastic plate 9 stacked on the bottom surface of the battery stack block 2 is thermally coupled to the cooling plate 30. It can also be set as the structure connected. The battery system 200 can cool the cooling plate 30, cool the elastic plate 9 with the cooling plate 30, and cool the battery cell 1 via the elastic plate 9. The cooling plate 30 can be cooled by providing radiating fins (not shown) on the surface, or can be forcibly cooled by circulating a cooling refrigerant or coolant inside.

  In the insulating spacer 5 in FIG. 6, the horizontal portion 22 is disposed outside the terminal surface 1 </ b> A and the bottom surface 1 </ b> B of the battery cell 1. The first horizontal portion 22A disposed on the outside of the terminal surface 1A, in the drawing, is sandwiched between the fitting portion 4A of the binding device 4 and the terminal surface 1A of the battery cell 1, and the upper surface is the fitting portion. The lower surface is in close contact with the terminal surface 1A at 4A. The fitting portion 4A of the binding tool 4 presses the terminal surface 1A via the first horizontal portion 22A, and the terminal surfaces 1A of the respective battery cells 1 are arranged on the same plane with the fitting portions 4A. The second horizontal portion 22B arranged outside the bottom surface 1B of the battery cell 1 and below the bottom surface 1B in the figure is between the bottom surface 1B of the battery cell 1 and the elastic arm 19A as the elastic pressing portion 19, and the top surface is In close contact with the bottom surface 1B of the battery cell 1, the lower surface is pressed by the elastic arm 19A. The elastic arm 19A pushes up the bottom surface 1B of the battery cell 1 via the second horizontal portion 22B, and the terminal surface 1A of each battery cell 1 is arranged on the same plane with the fitting portion 4A.

  The elastic plate 9 is disposed on the bottom surface 1B of the battery cell 1 and has an elastic pressing portion 19 that elastically presses each battery cell 1 from the bottom surface 1B toward the terminal surface 1A. The elastic plate 9 shown in FIGS. 5 and 8 is formed by cutting a metal plate such as stainless steel that can be elastically deformed, and pressing the elastic plate 19 to form a plurality of elastic arms 19 </ b> A as elastic pressing portions 19. Further, the elastic plate 9 of FIGS. 5 and 8 is provided with a pair of elastic arms 19 </ b> A extending in the longitudinal direction of the bottom surface 1 </ b> B of the battery cell 1. The pair of elastic arms 19 </ b> A are connected to the elastic plate 9 at both sides of the elastic plate 9, and are provided so as to extend from both sides of the elastic plate 9 toward the center. The illustrated elastic plate 9 includes a rectangular outer peripheral frame portion 9A that follows the outer shape of the bottom surface of the battery stack block 2, and a plurality of elastic arms 19A extending inward from both side portions of the outer peripheral frame portion 9A are integrally formed. Provided. The elastic arm 19A is bent into a shape protruding toward the bottom surface 1B of the battery cell 1 toward the tip. A pair of elastic arms 19 </ b> A provided on both sides of the elastic plate 9 presses the bottom surface 1 </ b> B of one battery cell 1. Therefore, the interval between the adjacent elastic arms 19A is equal to the interval between the stacked battery cells 1, and a plurality of elastic arms 19A are provided on both sides of the elastic plate 9.

  Further, the elastic plate 9 shown in FIGS. 3 and 8 is provided with reinforcing ribs 9B along both side edges of the outer peripheral frame portion 9A. The elastic plate 9 shown in the figure is provided with reinforcing ribs 9B by bending both side edges of the outer peripheral frame portion 9A upward. The elastic plate 9 can increase the rigidity of both side portions of the outer peripheral frame portion 9A by the reinforcing ribs 9B provided on both side edges. The elastic plate 9 having this structure is characterized in that it can be pressed without deforming both side portions of the outer peripheral frame portion 9A in a state of pressing both side portions and elastically deforming the elastic pressing portion 19 in the battery system assembly process. Further, the illustrated elastic plate 9 has a structure in which the inner surfaces of the reinforcing ribs 9B provided on both side edges of the outer peripheral frame portion 9A are in contact with the outer surface of the lower corner portion of the battery stack 2. The elastic plate 9 has a feature that it can be placed at a fixed position while positioning the left and right positions with the reinforcing ribs 9B on both sides with respect to the bottom surface of the battery stack 2.

  The end plate 3 is connected to the binding tool 4, pressurizes the battery stack block 2 from both end surfaces, and presses the battery cells 1 in the stacking direction. The end plate 3 is fixed to the binding tool 4 to fix each battery cell 1 of the battery stack 2 in a pressurized state with a predetermined tightening pressure. The outer shape of the end plate 3 is substantially the same as or slightly larger than the outer shape of the battery cell 1, and the battery stacking block 2 is fixed in a pressurized state by connecting the binding tools 4 to the four corners so as not to be deformed. It is a plate shape. This end plate 3 connects the binding tool 4 to the four corners, is in close contact with the surface of the battery cell 1 in a surface contact state, and fixes the battery cell 1 in a pressurized state with a uniform pressure. In the battery system, end plates 3 are arranged at both ends of the battery stack 2 and the end plates 3 at both ends are pressed by a press machine (not shown) to hold the battery cells 1 in the stacking direction. In this state, the binder 4 is fixed to the end plate 3, and the battery stack 2 is held and fixed at a predetermined tightening pressure. After the end plate 3 is connected to the binding tool 4, the pressurization state of the press machine is released.

  1, 2, 4, and 5, the binding tool 4 connects the end plates 3 at both ends of the battery stack block 2, and presses the plurality of battery cells 1 in the stacking direction. Fix it. The binding tool 4 is manufactured by pressing a metal plate. As shown in FIG. 9, the binding tool 4 includes a side plate 4 </ b> X disposed on the side surface of the battery stack block 2, and an L disposed on the outer surface of the end plate 3 at both ends of the side plate 4 </ b> X. The L-shaped fixing portion 4 </ b> C is fixed to the outer end surface of the end plate 3 via a set screw 18.

  Furthermore, the binding tool 4 includes a fitting portion 4A disposed outside the terminal surface 1A of the battery cell 1 and a locking portion 4B disposed outside the elastic plate 9. The battery stack block 2 in which the elastic plate 9 is stacked on the bottom surface 1B is disposed between the fitting portion 4A and the locking portion 4B. The binding tool 4 of FIGS. 3 and 9 is provided with a fitting portion 4A by bending the upper edge of the side plate 4X inward at a right angle and providing a locking portion 4B by bending the lower edge at a right angle. ing. Further, the side plate 4X is lightened by providing a cut portion 4D inside the outer peripheral edge portion. The side surface plate 4X in FIG. 9 reinforces the frame frame 4E by connecting a rectangular frame frame 4E at the outer peripheral edge in the vertical and horizontal directions with a connecting bar 4F.

  4 A of fitting parts make the inner surface planar, and arrange | position the terminal surface 1A of each battery cell 1 on the same plane. In the battery system 100 of FIG. 3, the horizontal portion 22 of the insulating spacer 5 is disposed on the terminal surface 1 </ b> A of the battery cell 1. Therefore, the battery system 100 is arranged such that the horizontal portion 22 of the insulating spacer 5 is sandwiched between the terminal surface 1A and the fitting portion 4A. The terminal surface 1A of the battery cell 1 is pressed against the fitting portion 4A via the horizontal portion 22 and arranged on the same plane. In the battery system of the present invention, the horizontal portion of the insulating spacer is not necessarily arranged on the terminal surface of the battery cell. This battery system arrange | positions a terminal surface so that the inner surface of a fitting part may be contacted, and arrange | positions the terminal surface of each battery cell on the same plane. In this battery system, the fitting portion and the terminal surface are made of an insulating material, or a laminated sheet and an insulating layer are provided between the fitting portion and the terminal surface.

  The locking portion 4B is outside the elastic plate 9, below the elastic plate 9 in FIG. 3, and holds the elastic plate 9 in a state of being elastically deformed so as to push up the elastic plate 9 and crush the elastic pressing portion 19 of the elastic plate 9. . The elastic plate 9 pressed against the bottom surface of the battery stack 2 by the engaging portion 4B presses the battery cell 1 with the restoring force of the elastic pressing portion 19 that is elastically deformed, so that the terminal surface 1A of the battery cell 1 is the same. Place on a flat surface. In the battery system 100 of FIG. 3, the horizontal portion 22 of the insulating spacer 5 is disposed between the elastic plate 9 and the bottom surface 1 </ b> B of the battery cell 1. Therefore, the elastic pressing part 19 pushes up the battery cell 1 via the horizontal part 22 and arranges the terminal surface 1A on the same plane.

  The inner distance between the fitting portion 4A and the locking portion 4B is such that the battery stack 2 having the elastic plate 9 disposed on the bottom surface 1B is disposed and the elastic pressing portion 19 of the elastic plate 9 is crushed and elastically deformed. . In the battery system in which the horizontal portion 22 of the insulating spacer 5 is disposed between the fitting portion 4A and the locking portion 4B and the battery cell 1, the inner spacer between the fitting portion 4A and the locking portion 4B is vertically insulated. The battery stack block 2 is disposed by laminating 5 horizontal portions 22 and placing the elastic plate 9 on the bottom surface 1B, and the elastic pressing portion 19 of the elastic plate 9 is crushed and elastically deformed.

  Further, as shown in FIG. 9, the binding tool 4 holds the elastic pressing portion 19 in a crushed state when the elastic plate 9 and the battery stack 2 are inserted between the fitting portion 4A and the locking portion 4B. A notch 4a for guiding the jig is provided in both the fitting portion 4A and the locking portion 4B. In the illustrated binding tool 4, the notch 4 a is provided in both the fitting part 4 </ b> A and the locking part 4 </ b> B, but the present invention does not necessarily require the notch in both the fitting part and the locking part. In addition, a cutout can be provided in one of the fitting portion and the locking portion. The battery stack block is formed by pressing a battery stack block with a jig or holding an elastic plate by pressing an elastic plate and crushing the elastic pressing portion while laminating an elastic plate while guiding a notch in the jig. This is because it can be inserted between the fitting portion and the locking portion.

  Furthermore, the binding tool 4 of FIG.4, FIG.5 and FIG.9 has provided the notch 4a in the both ends of the fitting part 4A and the latching | locking part 4B. A jig for pressing the battery stack block 2 and crushing the elastic pressing portion 19 of the elastic plate 9 through the first horizontal portion 22A of the insulating spacer 5 is guided to the notch 4a of the fitting portion 4A. A jig for pressing the elastic plate 9 and crushing the elastic pressing portion 19 is guided to the notch 4a of the locking portion 4B. The elastic pressing portion 19 crushed by the jig presses the battery stack block 2 via the second horizontal portion 22B of the insulating spacer 5.

  The above-described binding tool 4 is provided with a notch 4 a located at an end spacer 5 ′ stacked on both ends of the battery stack block 2. The end spacer 5 ′ is stacked between the endmost stacked battery cell 1 ′ stacked on both ends of the battery stack 2 and the end plate 3. The binding tool 4 provided with the notches 4a at both ends is configured to apply stress concentrated on the corners of the side plate 4X with the notches 4a at both ends in a state where the fixing portion 4C is fixed to the outside of the end plate 3. Dispersion can prevent damage to the side plate 4X. Since the binding tool 4 of FIG. 9 is provided with the notches 4a at both ends of the fitting portion 4A and the locking portion 4B, the stress concentrated on the upper and lower corner portions of the side plate 4X is dispersed, There is a feature that can prevent damage to the four corners of the plate 4X.

  Furthermore, the binding tool 4 of FIG. 9 is provided with a separation gap 4b between the L-shaped fixing portion 4C and the fitting portion 4A and the locking portion 4B. The binding tool 4 having this shape can be produced in large quantities at a low cost by pressing a metal plate. Further, the binding tool 4 can be produced at both the notch 4a provided in the fitting portion 4A and the locking portion 4B and the separation gap 4b. Therefore, the stress concentration acting on the four corners of the side plate 4X can be more effectively prevented and dispersed, and damage to this portion can be more effectively prevented.

The above battery system 100 is assembled in the following steps.
(1) The battery cell 1 and the insulating spacer 5 are alternately laminated on the elastic plate 9 arranged in a horizontal posture to form the battery laminated block 2.

(2) End plates 3 are arranged at both ends of the battery stack 2 and the battery stack 2 is pressed in the stacking direction. At this time, each battery cell 1 is pushed up by the elastic pressing portion 19 of the elastic plate 9, and the terminal surface 1A of the battery cell 1 is arranged on the same plane. In order to realize this, the first horizontal portion 22A of the insulating spacer 5 arranged on the terminal surface 1A of the battery cell 1 is arranged on the same plane. The first horizontal portion 22A can be arranged on the same plane by placing a horizontal rod or a horizontal bar thereon and pressing it.

(3) As shown in FIG. 10, the elastic plates 9 stacked on the bottom of the battery stack block 2 are provided at both ends of the fitting portion 4A in a state of being locked to the locking portion 4B of the binding tool 4. At a position where the cutout 4a is guided, the battery stack block 2 is pressed with a jig (indicated by an arrow A in the figure), the battery stack block 2 is pressed down, and an elastic arm 19A which is an elastic pressing portion 19 of the elastic plate 9 Is held in a state of being crushed. In this state, the battery stack 2 is inserted inside the fitting portion 4A. In a state where the battery stack block 2 is inserted inside the fitting portion 4A, the jig pressing the battery stack block 2 is guided to the notch 4a. Therefore, the battery stack 2 and the elastic plate 9 can be inserted inside the fitting portion 4A and the locking portion 4B while pressing the battery stack 2 with a jig.

  In the above method, the battery stack block 2 is pressed with a jig at a position where the notch 4a of the fitting portion 4A is guided. However, at the position where the notch 4a of the locking portion 4B is guided by the following method. The elastic plate 9 can also be pressed with a jig. In this method, as shown in FIG. 11, notches provided at both ends of the locking portion 4B in a state where the horizontal base 35 is in contact with the upper surface of the battery stack block 2 in which the elastic plate 9 is stacked on the bottom. In a position where 4a is guided, the elastic plate 9 is pressed with a jig (indicated by an arrow B in the figure), the elastic plate 9 is pushed up, and the elastic arm 19A which is the elastic pressing portion 19 of the elastic plate 9 is crushed. Hold on. In this state, the elastic plate 9 laminated on the battery laminated block 2 is inserted inside the fitting part 4A and the engaging part 4B of the binding tool 4 together with the battery laminated block 2. In a state where the battery stack 2 and the elastic plate 9 are inserted inside the fitting portion 4A and the locking portion 4B, the jig pressing the elastic plate 9 is guided to the notch 4a of the locking portion 4B. Accordingly, the battery stack 2 and the elastic plate 9 can be inserted inside the fitting portion 4A and the locking portion 4B while pressing the elastic plate 9 with a jig.

(4) The battery stack block 2 and the elastic plate 9 are inserted in a stacked state between the fitting portion 4A and the locking portion 4B of the binding tool 4, and the L-shaped fixing portion 4C of the binding tool 4 in this state. Is fixed to the outside of the end plate 3. Thereafter, the state where the jig presses the battery stack 2 and the elastic plate 9 is released.

  In the above method, the battery stack 2 is mounted on the elastic plate 9 and assembled. However, the above method may be reversed and the elastic plate 9 may be mounted on the battery stack 2 and assembled. In this method, a battery system is assembled as follows.

(1) As shown in FIG. 12, the battery cell block 2 is formed by placing the terminal surfaces 1A of the battery cells 1 on the horizontal base 35 arranged in a horizontal posture and alternately stacking the battery cells 1 and the insulating spacers 5. Then, the elastic plate 9 is placed on the battery stack 2.

(2) End plates 3 are arranged at both ends of the battery stack 2 and the battery stack 2 is pressed in the stacking direction.

(3) The elastic plate 9 is pressed with a jig (indicated by an arrow B in the figure) at a position where the notches 4a provided at both ends of the engaging portion 4B of the binding device 4 are guided, and the elastic plate 9 is stacked in the battery stack. The elastic arm 19 </ b> A that is the elastic pressing portion 19 of the elastic plate 9 is pressed against the block 2 and held in a crushed state. In this state, the elastic plate 9 laminated on the battery laminated block 2 is inserted inside the fitting part 4A and the engaging part 4B of the binding tool 4 together with the battery laminated block 2. In a state where the battery stack 2 and the elastic plate 9 are inserted inside the fitting portion 4A and the locking portion 4B, the jig pressing the elastic plate 9 is guided to the notch 4a of the locking portion 4B. Accordingly, the battery stack 2 and the elastic plate 9 can be inserted inside the fitting portion 4A and the locking portion 4B while pressing the elastic plate 9 with a jig.

  In the above method, the elastic plate 9 is pressed by a jig at a position where the notch 4a of the locking portion 4B is guided. However, the position where the notch of the fitting portion is guided by the jig is pressed by the following method. You can also. Although this method is not shown, the notch provided at both ends of the fitting portion is guided in a state where the elastic plate stacked on the battery stacking block is locked to the locking portion of the binding tool. The battery stack block is pressed with a jig, the battery stack block is pushed up, and the elastic arm that is the elastic pressing portion of the elastic plate is held in a crushed state. In this state, the battery laminated block on which the elastic plate is laminated is inserted inside the fitting portion. In a state where the battery laminated block is inserted inside the fitting portion, the jig pressing the battery laminated block is guided to the notch of the fitting portion. Therefore, the battery stack block and the elastic plate can be inserted inside the fitting portion and the locking portion while pressing the battery stack block with the jig.

(4) The battery stack block 2 and the elastic plate 9 are inserted in a stacked state between the fitting portion 4A and the locking portion 4B of the binding device 4, and in this state, the L-shaped fixing portion of the binding device 4 4C is fixed to the outside of the end plate 3. Thereafter, the state where the jig presses the battery stack 2 and the elastic plate 9 is released.

  The battery system described above is most suitable for a power supply device that supplies electric power to a motor that drives an electric vehicle. As an electric vehicle equipped with a battery system, an electric vehicle such as a hybrid vehicle or a plug-in hybrid vehicle that runs with both an engine and a motor, or an electric vehicle that runs only with a motor can be used, and used as a power source for these electric vehicles. Is done. However, the present invention does not specify the use of the battery system as a power supply device mounted on an electric vehicle, and can be used, for example, as a power supply device that stores natural energy such as solar power generation or wind power generation, and stores midnight power. Like power supply devices such as power supply devices, it is optimal for all applications that store large amounts of power.

  The battery system of the present invention is optimally used for a power supply device that supplies electric power to a motor of a vehicle that requires a large amount of power, or a power storage device that stores natural energy or midnight power.

DESCRIPTION OF SYMBOLS 100, 200 ... Battery system 1 ... Battery cell 1 '... Endmost laminated battery cell 1A ... Terminal surface 1B ... Bottom surface 1C ... Flat surface 2 ... Battery laminated block 3 ... End plate 4 ... Binder 4X ... Side plate 4A ... Fitting Part 4B ... Locking part 4C ... L-shaped fixing part 4D ... Cut part 4E ... Frame frame 4F ... Connection bar 4a ... Notch 4b ... Separation gap 5 ... Insulating spacer 5 '... End spacer 9 ... Elastic plate 9A ... Outer frame Part 9B ... Reinforcing rib 10 ... Battery case 10A ... Exterior can 10B ... Sealing plate 11 ... Exhaust valve 12 ... Gas exhaust port 13 ... Electrode terminal 14 ... Bus bar 14A ... Linear bus bar 14B ... L-shaped bus bar 14a ... Through hole DESCRIPTION OF SYMBOLS 15 ... Set screw 16 ... Nut 18 ... Set screw 19 ... Elastic press part 19A ... Elastic arm 20 ... Plate part 22 ... Horizontal part 22A ... 1st horizontal part 2B ... 2nd horizontal part 25 ... Groove 26 ... Cooling gap 30 ... Cooling plate 35 ... Horizontal stand 901 ... Battery cell 901A ... Terminal surface 902 ... Battery stacking block 904 ... Binder 904A ... Fitting part 904B ... Locking part 905 ... Insulating spacer 909 ... Elastic plate 919 ... Elastic pressing part

Claims (4)

A plurality of battery cells provided with positive and negative electrode terminals on the terminal surface are stacked in the thickness direction, and each battery cell is electrically connected through a bus bar fixed to the electrode terminal of each battery cell. A battery stack block;
An elastic plate that is disposed on the bottom surface located on the opposite side of the terminal surface of the battery cell and has an elastic pressing portion that elastically presses each battery cell from the bottom surface toward the terminal surface;
A pair of end plates at both ends of the battery stack, for pressing and fixing the battery cells in the stacking direction;
A battery system comprising a binding tool that connects a pair of end plates and fixes a plurality of battery cells in a stacked state in a pressurized state,
The binding tool has a fitting portion arranged outside the terminal surface of the battery stack, and a locking portion arranged outside the elastic plate,
The battery stack block and the elastic plate are disposed between the fitting part and the locking part of the binding tool, and the elastic pressing part is elastically deformed, and each elastic pressing part is elastically restored by an elastic restoring force. The battery cell is elastically pressed toward the fitting portion,
The battery system further comprises a notch for guiding a jig for pressing the battery stack or the elastic plate in one or both of the fitting portion and the locking portion. The battery system according to claim 1,
A battery system, wherein the notches are provided at both ends of a binding tool. The battery system according to claim 1 or 2,
The binding device includes a side plate arranged on a side surface of the battery stack, and an L-shaped fixing portion connected to both end portions of the side plate and arranged on an outer end surface of the end plate,
The battery system, wherein the fitting portion and the locking portion are provided on both side edges of the side plate, and notches are provided at both ends of the fitting portion and the locking portion. A plurality of battery cells provided with positive and negative electrode terminals on the terminal surface are stacked in the thickness direction, and each battery cell is electrically connected through a bus bar fixed to the electrode terminal of each battery cell. A battery stack block;
An elastic plate that is disposed on the bottom surface of the battery stack and has an elastic pressing portion that elastically presses each battery cell from the bottom surface toward the terminal surface;
A pair of end plates at both ends of the battery stack, for pressing and fixing the battery cells in the stacking direction;
A pair of end plates connected to each other, and a binding tool for fixing a plurality of battery cells in a pressurized state in the stacking direction,
The binding tool has a fitting portion arranged outside the terminal surface of the battery stack, and a locking portion arranged outside the elastic plate,
The battery stack block and the elastic plate are disposed between the fitting part and the locking part of the binding tool, and the elastic pressing part is elastically deformed, and each elastic pressing part is elastically restored by an elastic restoring force. A battery system manufacturing method in which a battery cell is elastically pressed toward the fitting portion,
While providing either one or both of the fitting part and the locking part of the binding tool with a notch for guiding a jig for pressing the battery stack block or the elastic plate,
The elastic plate is disposed on the bottom surface of the battery stack, and end plates are disposed at both ends of the battery stack, and each battery cell is pressed in the stacking direction with the end plate. With the guided jig, the elastic pressing portion of the elastic plate is held in an elastically deformed state, and the battery stack block and the elastic plate are arranged between the fitting portion and the locking portion of the binding tool. And the said jig is guided to the said notch, The said binding tool is fixed to the said end plate in this state, The manufacturing method of the battery system characterized by the above-mentioned.

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