Battery pack

Abstract

A battery pack having a plurality of battery blocks is manufactured at low cost. The specific structure of the invention is as follows. A battery pack in which, arranged in a direction perpendicular to a second direction: a first battery block having a structure in which a plurality of first batteries (1) and a plurality of first spacers (20) are alternately stacked in the first direction; and a second battery block having a structure in which a plurality of second batteries (1) and a plurality of second spacers (20) are alternately stacked in the first direction, the battery pack being characterized in that: the first spacers and the second spacers are integrally formed via first connection sections; an inter-block side rail (70) for commonly pressing the first battery block and the second battery block in the first direction is disposed on the first connection parts (22, 23).

Description

Technical Field

[0001] The present invention relates to a battery pack having a plurality of battery blocks, wherein the battery block has a plurality of batteries. Background Art

[0002] At present, in the field of rechargeable secondary batteries, aqueous solution batteries such as lead batteries, nickel-cadmium batteries, and nickel-hydrogen batteries are the mainstream. However, with the miniaturization and lightweight development of electrical equipment, lithium secondary batteries with high energy density have attracted much attention, and their research, development, and commercialization are progressing rapidly.

[0003] On the other hand, due to the problems of global warming and fuel depletion, various automobile manufacturers have developed electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are partially driven by electric motors. As their power sources, high-capacity and high-output secondary batteries are required. As a power source that meets this requirement, lithium secondary batteries with high-voltage non-aqueous solutions have attracted much attention. In particular, square lithium secondary batteries have excellent volume efficiency when packaged, so expectations for the development of square lithium secondary batteries for HEVs or EVs are constantly increasing.

[0004] When multiple secondary batteries are modularized, each battery cell needs to be held by an insulating spacer such as resin. Therefore, the number of insulating spacers required is always N+1 relative to the number of battery cells N, and the assembly method requires alternately stacking battery cells and insulating spacers one by one.

[0005] Multiple batteries are restrained in the stacking direction, but the positions of the batteries are offset before and after being restrained. Patent Document 1 describes a structure for the following battery arrangement, for example, when two battery blocks are restrained by a common restraining plate, stress is not generated in each battery even if the positions of the batteries are offset. In Patent Document 1, even when the restraining plate is common in multiple battery blocks, the spacers between the batteries are different parts in each battery block.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2019-149227 Summary of the invention

[0009] Problems to be solved by the invention

[0010] In the present invention, the combination of a battery and a spacer is called a battery block, and the component formed by combining the battery block is called a battery pack. The battery block is assembled by alternately overlapping the battery cells and the insulating spacers one by one. In the prior art including Patent Document 1, the battery cells and the insulating spacers are assembled by alternately overlapping one by one. Therefore, the more battery cells there are, the more working hours and the number of parts are increased. Therefore, the manufacturing cost is increased.

[0011] Furthermore, if a sufficient output voltage cannot be obtained from one battery block, it is necessary to further connect multiple battery blocks to form a battery pack for use. In this case, in the prior art, the battery user, such as an automobile manufacturer, needs to connect the purchased battery blocks by the company itself.

[0012] Therefore, the process of assembling a plurality of batteries with spacers interposed therebetween to form a battery block and the process of arranging a plurality of such battery blocks to form a battery pack are both a heavy burden on the manufacturing cost for battery manufacturers and battery users. The subject of the present invention is to realize a structure that shortens and simplifies the process of forming such a battery pack as a whole and reduces the manufacturing cost of the battery pack.

[0013] In other words, an object of the present invention is to provide a secondary battery module using two or more battery cells, which can suppress an increase in the number of parts of the accompanying insulating spacers and the number of work hours for assembling them even if the number of battery cells used increases.

[0014] Technical solutions to solve problems

[0015] The present invention is an invention for solving the above-described problems, and its main structure is as follows. That is, instead of assembling battery blocks one by one, multiple battery blocks are assembled at the same time. Specifically, the spacers, end plates, and side plates used for binding arranged between the batteries are made common to each block constituting the battery pack. Then, by assembling multiple blocks at the same time instead of assembling the battery pack for each block, the working hours are reduced. The specific scheme of the present invention is as follows.

[0016] (1) A battery pack, comprising: a first battery block having a structure in which a plurality of first batteries and a plurality of first spacers are alternately stacked in the first direction; and a second battery block having a structure in which a plurality of second batteries and a plurality of second spacers are alternately stacked in the first direction, wherein the first spacers and the second spacers are integrally formed via a first connecting portion, and an inter-block side rail for pressing the first battery block and the second battery block together in the first direction is arranged on the first connecting portion.

[0017] (2) A battery pack according to (1), wherein a first end plate is arranged at both ends of the first battery block in the first direction, and a second end plate is arranged at both ends of the second battery block in the first direction, and the inter-block side rail presses the first battery block in the first direction via the first end plate, and presses the second battery block in the first direction via the second end plate.

[0018] (3) The battery pack according to (2), wherein the first end plate and the second end plate are continuously formed via a second connecting portion, and the inter-block side rails are arranged at the second connecting portion.

[0019] Effects of the Invention

[0020] According to the present invention, since a plurality of battery blocks are assembled at the same time, the cost of the assembly process is greatly reduced. In addition, according to the present invention, the insulating plates that sandwich the battery cells are connected and integrated between blocks instead of for each block, so the number of parts can also be reduced. Furthermore, among battery users, a plurality of battery blocks are purchased in a state where they are already connected, so the man-hours for connecting the battery blocks can also be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional diagram of a battery.

[0022] Figure 2 This is an exploded perspective view of the battery pack.

[0023] Figure 3 It is a top view of a battery pack in which four battery blocks are arranged in a comparative example.

[0024] Figure 4 This is a plan view of a battery pack in which four battery blocks are arranged in Embodiment 1 of the present invention.

[0025] Figure 5 This is an exploded perspective view of a battery pack having four battery blocks arranged therein in Embodiment 1 of the present invention.

[0026] Figure 6 This is a perspective view of the spacer of Example 1.

[0027] Figure 7 This is a perspective view of the side rails between blocks of Example 1.

[0028] Figure 8 It is a perspective view showing another example of the spacer.

[0029] Fig. 9 It is a perspective view showing still another example of the spacer.

[0030] Fig.10 This is a perspective view of the battery pack of Example 2.

[0031] Fig.11 This is an exploded perspective view of the battery pack of Example 2.

[0032] Fig.12 This is a perspective view of the battery pack of Example 3.

[0033] Fig.13 This is an exploded perspective view of the battery pack of Example 3.

[0034] Fig.14 This is a perspective view of the battery pack of Example 4.

[0035] Fig.15 This is an exploded perspective view of the battery pack of Example 4. DETAILED DESCRIPTION

[0036] Hereinafter, the present invention will be described in detail by way of examples.

[0037] Example 1

[0038] The present invention is characterized in that it is a structure capable of simultaneously forming a plurality of battery blocks. First, a conventional single block assembly structure will be described as a comparative example.

[0039] Figure 1 is a three-dimensional diagram of the battery unit 1. Figure 1 As shown, the battery cell 1 includes a battery can 2, a battery cover 3, a positive terminal 4, a negative terminal 5, a gas exhaust valve 6, an electrolyte solution (not shown), a charging and discharging element, and an insulating shell. The battery cell 1 uses a rechargeable and dischargeable secondary battery such as a lithium ion secondary battery. The battery cell 1 of the first embodiment corresponds to a single cell of a battery pack of one embodiment of the present invention.

[0040] The battery can 2 has a rectangular shape with one end of the internal space opened, and is made of aluminum or aluminum alloy. The battery can 2 has a pair of opposing side plates 2a with a large area, a pair of opposing side plates 2b with a small area, and a bottom plate 2c on the opposite side of the opening. In the internal space of the battery can 2, the charging and discharging elements are stored in a state covered by an insulating shell and injected with electrolyte. The positive electrode of the charging and discharging element is connected to the positive terminal 4, and the negative electrode of the charging and discharging element is connected to the negative terminal 5.

[0041] The battery cover 3 has the same rectangular flat plate shape as the bottom plate 2c, is made of aluminum or aluminum alloy, and closes the opening of the battery can 2. The battery cover 3 is joined to the opening of the battery can 2 by joining means such as laser welding. A gas discharge valve 6 is provided in the central portion of the battery cover 3. The battery cell 1 generates heat and gas due to abnormalities such as overcharging. When the pressure inside the battery can 2 rises and reaches a predetermined pressure, the gas discharge valve 6 opens to discharge gas from the container, thereby reducing the pressure inside the battery can 2.

[0042] In addition, through holes (not shown) are formed at one end and the other end of the battery cover 3, and a positive terminal 4 and a negative terminal 5 are installed. The portions of the positive terminal 4 and the negative terminal 5 exposed to the outside from the battery cover 3 are respectively formed in a rectangular parallelepiped and have a flat top surface. The power generated by the battery cell 1 is supplied to an external device via the positive terminal 4 and the negative terminal 5, or the power generated externally is supplied to the charging and discharging element via the positive terminal 4 and the negative terminal 5 for charging.

[0043] Figure 2 This is an exploded perspective view of the battery pack. Figure 2 As shown, the battery block has a plurality of stacked battery cells 1 and a spacer 20 , a pair of end spacers 30 , a pair of end plates 40 , and a pair of side rails 50 .

[0044] The spacer 20 is made of a synthetic resin having insulating properties, such as Figure 2 As shown, the spacers 20 are alternately inserted between adjacent battery cells 1 and stacked in the x direction together with the battery cells 1. Each spacer 20 has a protrusion 21 extending in the x direction at the end, and the battery cell 1 is held in the recess formed by the protrusion 21, restricting the y direction and the Z direction. In addition, in this specification, when the x direction is set as the first direction, the second direction perpendicular to the x direction may be set as the y direction.

[0045] The terminal spacer 30 basically has the same structure as the spacer 20. That is, it is made of a synthetic resin having insulating properties, and the battery cell 1 located at the outermost side is arranged on the outside. Since the battery cell 1 is arranged only on one side of the terminal spacer 30, the protrusion 31 is formed only on one side of the terminal spacer 30.

[0046] An end plate 40 is disposed outside the end spacer 30. The end plates 40 on both sides are pressed in the x direction by the side rails 50 to fix the stack of the battery cell 1 and the spacer 20. The end plate can be formed of metal or resin. In short, it is necessary to have mechanical strength to stably restrain the stack of the battery cell 1 and the spacer 20.

[0047] exist Figure 2In the embodiment, the holes 51 of the side rails 50 and the holes 41 of the end plates are overlapped, and the stacked body of the battery cells 1 and the spacers 20 is fastened and fixed in the x direction by screws 60. The side rails 50 are generally formed of metal.

[0048] exist Figure 2 In the embodiment, a busbar cover 200 formed of an insulating material such as resin is arranged corresponding to the terminals 4 and 5 formed on the battery cell 1. The battery cell 1 is arranged so that the terminals of adjacent batteries become positive or negative electrodes. Then, the positive electrodes 4 and negative electrodes 5 of adjacent batteries are connected by busbars 210. The outermost terminals of each block are connected to the end busbars 220 to connect to other battery blocks or external circuits.

[0049] Most battery blocks are used by connecting a plurality of battery cells 1 in series, but even when connected in series, sometimes a sufficient output voltage cannot be obtained. In this case, a plurality of battery blocks are connected in series for use. In addition, when the output current is to be increased, the battery blocks are connected in parallel. This is a problem of connection between terminals, and the present invention can be applied to both.

[0050] Figure 3 The figure on the upper side is a top view showing a state where four battery blocks are arranged side by side and connected in series. Figure 3 In the process, the individual battery blocks are assembled separately. Figure 3 In the embodiment, the battery cells 1 and the spacers 20 are alternately stacked. Figure 3 In order to avoid making the figure complicated, the protrusion formed on the end of the spacer 20 is omitted. The stacked body of the battery cell 1 and the spacer 20 is sandwiched by the end spacer 30 and the end plate 40, and is pressed and fixed by the side rail 50.

[0051] exist Figure 3 In the battery cell 1, the positive terminal 4, the negative terminal 5, the gas exhaust valve 6, the electrolyte injection hole and the plug 7 are omitted. The adjacent batteries are stacked in the opposite direction so that the positive terminals and negative terminals of the adjacent batteries 1 are adjacent to each other. Figure 3 In the embodiment, adjacent positive and negative terminals are connected by busbars 210. Terminals at the ends of each block are connected to end busbars 220. The end busbars 220 are connected to electrode terminals of adjacent battery blocks or to terminals of external devices.

[0052] Figure 3 The figure below is a front view of each battery block. Figure 3 In the embodiment, the flange of the side rail 50 is stacked on the end plate 40 so that the hole formed in the flange overlaps with the hole in the end plate, and the stack of the battery cell 1 and the spacer 20 is sandwiched and pressed and fixed by the screws 60 .

[0053] Figure 3The structure of the battery manufacturer is to manufacture four battery blocks independently. Therefore, the manufacturing cost is four times the manufacturing cost of each battery block. In addition, the four battery blocks are connected by the user. Therefore, the user side also has a corresponding burden.

[0054] Figure 4 1 is a top view and a front view of a battery pack according to Embodiment 1 of the present invention. Figure 4 In order not to complicate the figure, the protrusion of the spacer 20 is also omitted. Figure 4 The characteristic of the invention is that the four battery blocks are integrated and formed simultaneously. Figure 4 In the embodiment, the spacers 20 disposed between the battery cells 1 are formed into four pieces. Four battery cells 1 are arranged between the spacers. The end spacers 30 and the end plates 40 sandwiching the battery cells 1 and the spacers 20 from both sides are also formed into four pieces.

[0055] exist Figure 4 In the embodiment, the spacer 20, the end spacer 30, and the end plate 40 are provided with cutouts, and the extension 71 of the inter-block side rail 70 passes through the cutouts. The flange 72 of the inter-block side rail 70 presses the end plate 40 with screws 80 on the outside of the end plate 40, thereby pressing and fixing the battery block from both sides. Figure 4 and Figure 5 In the above description, pressing is the content of fastening, but pressing is a broader concept than fastening. For example, pressing may be performed by caulking or the like instead of using screws or the like.

[0056] The same structure is formed at three locations at the boundary of each battery block. Figure 3 Similarly, the outer sides of the battery blocks arranged on the outer sides are restrained by the side rails 50. In addition, the arrangement method of the battery unit 1 is the same as that of Figure 3 Therefore, the configuration of the busbar 210 and the end busbar 220 is basically the same as Figure 3 Same. Figure 4 In FIG. 4 , the battery pack is composed of four battery blocks, and the terminals connected to the outside are only two end bus bars 220 arranged at the battery blocks at both ends.

[0057] Figure 4 The figure below is a front view of the battery pack of Example 1. Figure 4 In the front view, the end plate 40 is formed integrally for the four battery blocks. The end plate 40 is formed with a cutout 42 at the boundary portion of the battery block, and the extension portion 71 of the inter-block side rail 70 is arranged in the cutout 42 portion. The flange 72 of the inter-block side rail 70 contacts the outer surface of the end plate 40 and is pressed by the screw 80. When the screw 80 is pressed, the two battery blocks are pressed by the end plate 40 and the inter-block side rail 70 and are restrained.

[0058] exist Figure 4In the front view, the width of the portion of the end plate 40 where the cutout 42 is formed becomes smaller. This portion is called a connecting portion 43. The connecting portion 43 can also be called a linking portion 43. The bending strength or cross-sectional modulus of the connecting portion 43 is smaller than that of other portions of the end plate 40. Therefore, even if a dimensional error occurs between battery blocks, stress can be eliminated in the connecting portion 43.

[0059] Figure 5 : is an exploded perspective view of Example 1. Figure 5 In the example, four battery blocks are formed into one piece. Figure 5 As shown, the battery cells 1 and the spacers 20 are alternately stacked in the x direction (sometimes referred to as the first direction). Figure 5 In the figure, the thickness of the spacer 20 is smaller than that of the battery cell 1, and therefore, it is described as a single sheet. In order not to complicate the figure, the protrusions 21 formed on the spacer 20 are omitted.

[0060] exist Figure 5 In the embodiment, the spacer 20 is formed in common in four battery blocks. In the spacer 20, a notch 22 is formed at the boundary portion of each block, and the extension portion 71 of the inter-block side rail 70 is inserted through the notch 22 portion. In the spacer 20, the bending strength or section modulus of the connection portion 23 of the portion where the notch 22 is formed is smaller than that of other portions. Therefore, even if a dimensional error occurs between the block batteries, it is assumed that the stress can be absorbed at the connection portion.

[0061] This feature is also the same in the terminal spacer 30. The terminal spacer 30 is formed in common in the four battery blocks, and a notch 32 is formed in the boundary portion. The width of the terminal spacer 30 at the portion where the notch 32 is formed becomes smaller, and the bending strength or the cross-sectional modulus is smaller than that of other portions. Therefore, even if a dimensional error occurs between the battery blocks, the stress can be absorbed in the connection portion 33.

[0062] The structure of the end plate 40 is as follows: Figure 4 The end plate 40 is also basically the same as the spacer 20 and the end spacer 30 . Figure 5 The extension portion 71 of the inter-block side rail 70 shown is inserted through the cutout 22 of the spacer 20, the cutout 32 of the end spacer 30, and the cutout 42 of the end plate 40. The flange portion 72 of the inter-block side rail 70 is used to press the two end plates 40 in the stacking direction (x direction) to fix the stacking structure of the battery cell 1 and the spacer.

[0063] exist Figure 5 In the y direction (also sometimes referred to as the direction perpendicular to the first direction), the outer sides of the battery blocks on both sides are the same as before, and the two end plates 40 are pressed by the side rails 50 to fix the battery cells 1 and the spacers 20 in the stacking direction. Figure 5In the embodiment, the spacer 20, the end spacer 30, and the end plate 40 are the same size as the four battery cells 1. Since the materials thereof are formed by resin molding, mass production is easy if the molding is designed at one time. Therefore, although the size is increased, the cost is not greatly increased. Rather, the number of parts is reduced, which has the effect of reducing costs.

[0064] The end plate 40 is often formed of metal, and in this case, is formed by stamping or die casting. In the case of stamping, if the stamping die is manufactured at one time, mass production is also easy. Therefore, when the end plate is formed of metal, the cost reduction effect caused by the reduction in the number of parts is greater than the main cause of the cost increase caused by the increase in the size of the parts.

[0065] Figure 6 It is a perspective view of the spacer 20 used in the present invention. Figure 6 The spacers 20 are spacers corresponding to four battery blocks. Figure 6 In the embodiment, the protrusion of the spacer 20 is omitted. Figure 6 In the embodiment, the spacer 20 has a notch 22 formed at a portion corresponding to the boundary portion of the battery block. The extension portion 71 of the inter-block side rail 70 is inserted through the notch 22 to press and fix the stack of the battery cells 1 and the spacer 20 .

[0066] exist Figure 6 In the case where the notch 22 is formed, the width of the spacer 20 is reduced, and this portion is referred to as a connecting portion 23 in this specification. In other words, the connecting portion 23 is a mechanically weak portion, and even if a certain dimensional error occurs between the battery blocks due to manufacturing error, the stress can be relieved by deformation of the connecting portion 23. In other words, the connecting portion 23 can be used as a mechanical buffer.

[0067] The connection portion 23 can be configured to actively function as a buffer. One of the configurations is that, in order to further reduce the mechanical strength of the connection portion 23, the thickness of the spacer in the connection portion 23 can be reduced compared to other portions. That is, the connection portion 23 only needs to be integral with the spacer 20 when the battery cell 1 is assembled into a block, so the reliability of the mechanical strength of the connection portion 23 of the spacer 20 does not become a problem.

[0068] As another means of using the connection portion 23 of the spacer 20 as a buffer, for example, in the spacer 20, only the connection portion is formed of an elastic material such as rubber or polypropylene. And the portion that functions as the spacer 20 is formed of an insulating resin. This structure can be formed by using a two-color molding method, for example. This structure is also the same for the end spacer 30 and the end plate 40.

[0069] Figure 7FIG. 2 is a perspective view of the inter-block side rail 70 inserted through the cutout portion 22 of the spacer 20 and the like. Figure 7 In the embodiment, the extension portion 71 of the inter-block side rail 70 is inserted through the cutout portion of the spacer 22, etc. The flange portion 72 is in contact with the end plate 40, and screws 80 are inserted and pressed into the screw holes 73 formed in the flange portion 72 and the screw holes formed in the end plate 40 to fasten the battery cell 1 and the spacer 20, thereby restraining the stack of the battery cell 1 and the spacer 20.

[0070] The inter-block side rails 70 can be formed by various methods. Figure 7 This is an example of forming a sheet metal plate by sheet metal processing. That is, for example, a shape corresponding to the developed plane of the inter-block side rail 70 is produced by punching. Then, by bending the sheet metal, it can be processed into Figure 7 Although the shape is different, the manufacturing process is basically the same as that of the side rail 50.

[0071] Figure 7 The inter-block side rail 70 shown is an example, and there are various other variations. It is not necessary to limit to sheet metal processing, and the extension portion 71 and the flange portion 72 of the inter-block side rail 70 can be manufactured separately, and they can be fixed by welding, fixing by screws, fixing by riveting (pressing / riveting / die forging / extrusion forging / fastening / fastening / fastening) and the like. Furthermore, in fixing the extension portion 71, it is also possible to directly attach it to the end plate 40 by means of welding, fixing by screws, riveting and the like.

[0072] Figure 6 This is an example in which a cutout 22 is formed on the upper side of the spacer 20. However, it is also possible to form a cutout 22 according to the layout requirements, such as Figure 8 As shown, a cutout 22 is formed on the lower side of the spacer 20. In this case, the connecting portion 23 is arranged on the upper side of the spacer, but the function is basically the same as for Figure 6 The instructions have the same effect. In addition, Figure 8 The structure can also be used with Figure 7 The inter-block side rails 70 have the same structure.

[0073] Fig. 9 This is an example of a case where a hole 25 is formed in the spacer 20 instead of a cutout at a portion corresponding to the boundary of the battery block. In this case, the inter-block side rail is inserted through the hole 25. Therefore, the inter-block side rail cannot be used in the same manner as the Figure 7 For example, a rod-shaped extension portion 71 of the inter-block side rail 70 having a cross section similar to that of the hole 25 of the spacer 20 is inserted through the end plate 40, and a flange 72 is attached to the extension portion 71 of the inter-block side rail 70 by screwing, riveting, or welding on the outer side of the end plate 40. Then, the flange 72 is used to press the stack of battery cells 1 and spacers 20 in the stacking direction.

[0074] In this embodiment, four examples are described, but the present invention is not limited thereto and can be configured using at least two battery blocks.

[0075] As an example of the fastening part of the present invention, the connection part 43 is used in this embodiment for explanation. In this embodiment, the end plate, the spacer, and the end spacer are set as a cutout structure. By forming it as one piece, the number of parts is reduced, so it is preferred. On the other hand, it is also possible to set the part as a structure in which a plurality of end plates, spacers, and end spacers are connected by connecting parts. Because the parts corresponding to each battery block can be manufactured separately, it is also easy to apply to battery packs with different numbers of battery blocks.

[0076] Example 2

[0077] Fig.10 This is a perspective view of the battery pack of Example 2. Fig.10 The structure of the embodiment 1 is different from that of the embodiment 1 in that the end plate and the side rails are integrated into one piece 100. Fig.10 In the , the battery blocks are arranged two by two instead of four. Fig.10 In the embodiment, the spacers and the end spacers are the same as those in the first embodiment, and are used to integrate the two battery blocks. Fig.10 In the block diagram, the battery cells 1 and the spacers 20 are alternately stacked in the stacking direction, but the spacers 20 are not visible. Instead, a protrusion 21 that is a part of the spacer 20 is visible at the end of the block.

[0078] exist Fig.10 In the embodiment, there are two battery blocks, but as in the embodiment 1 Figure 5 As shown in FIG. 1 , the spacers are integrated, and the battery unit is assembled simultaneously for two battery blocks. The two battery blocks are sandwiched by two end spacers 30 , respectively.

[0079] Fig.10 The difference from the first embodiment is that the end plate and the side rails are integrated into one piece 100. However, the integrated piece 100 is also pressed and restrained in the stacking direction by the inter-block side rails 70, similar to the first embodiment. The two integrated pieces 100 are connected by screws 101.

[0080] Fig.11 yes Fig.10 Exploded perspective view of the Fig.11 In the embodiment, the two end plates and the two side rails are replaced by two U-shaped plate-shaped integrated parts 100. The integrated parts 100 are simple shapes obtained by simply bending the plate-shaped parts. Therefore, they can be manufactured at low cost. The two integrated parts 100 are connected by screws 101.

[0081] exist Fig.11In the structure of the embodiment 1, the stacked structure of the battery cells 1 and the spacers 20 is pressed in the stacking direction by the inter-block side rails 70, which is the same as in the first embodiment. That is, the inter-block side rails are inserted through the spacers 20, the end spacers 30, and the cutouts of the integrated part 100, and press and restrain the stacked structure from the outside of the integrated part 100.

[0082] Example 3

[0083] Fig.12 is a three-dimensional diagram of the battery pack of Example 3, Fig.13 : is an exploded perspective view of the battery pack of Example 3. Fig.12 , Fig.13 In the embodiment, the end plates and the side rails are also formed as an integrated part 110 . Fig.12 , Fig.13 The structure of Example 2 Fig.10 The difference is the shape of the integrated part 110. Fig.12 , 13 In the embodiment, the two integral parts 110 are connected by screws 80 of the flanges of the side rails 70 between the blocks.

[0084] That is, the screws 80 press the battery cells 1 and the spacers 20 in the stacking direction and fix the integrated component 110. Compared with the structure of the second embodiment, the structure of the third embodiment can omit Fig.11 The other structures of the third embodiment are the same as those described in the second embodiment.

[0085] Example 4

[0086] Fig.14 : is a three-dimensional diagram of the battery pack of Example 4. Fig.14 In the embodiment 4, the end plate and the side rail are also integrated parts. However, in the structures of the second and third embodiments, the end plate and the side rail are formed as two integrated parts, but in the fourth embodiment, they are formed by only one part. That is, in the fourth embodiment, the integrated part 120 of the end plate and the side rail is a quadrilateral plate-shaped frame, and the stacked body of the battery cell 1 and the spacer 20 is inserted into the frame. Then, the stacked body of the battery cell 1 and the spacer 20 is pressed and restrained by the inter-block side rail 70, which is the same as in the second and third embodiments.

[0087] Fig.15 4 is an exploded perspective view of Example 4. Fig.15 As shown, the integrated component 120 of the end plate and the side rail is a plate-shaped rectangular frame. However, in the integrated component 120, a cutout 122 is formed at a portion corresponding to the cutout of the spacer 20 and the cutout of the end spacer 30.

[0088] The inter-block side rails 70 are inserted through the cutouts 122, and the stacked body of the battery cells 1 and the spacers 20 is pressed by screws 80 to restrain the battery blocks. The other structures of the fourth embodiment are the same as those described in the second and third embodiments. In the fourth embodiment, the end plates and the side rails are formed by one integrated part 120, so that the manufacturing cost can be further reduced.

[0089] Description of Reference Numerals

[0090] 1…battery, 2…battery can, 3…battery cover, 4…positive terminal, 5…negative terminal, 6…gas discharge valve, 20…spacer, 21…protrusion at end of spacer, 22…spacer cutout, 23…spacer connection portion, 30…end spacer, 31…protrusion at end of end spacer, 32…end spacer cutout, 33…end spacer connection portion, 40…end plate, 42…end plate cutout, 43…end plate connection portion, 50…side rail, 60…screw Nail, 70…inter-block side rail, 71…extension portion, 72…flange portion, 73…hole, 80…screw, 100…integrated part of end plate and side rail of Example 2, 101…screw, 102…cut, 110…integrated part of end plate and side rail of Example 3, 101…screw, 102…cut, 120…integrated part of end plate and side rail of Example 4, 122…cut, 200…busbar housing, 210…busbar, 220…end busbar.

Claims

1. A battery pack, characterized in that: In a direction perpendicular to the first direction, there are: A first battery block having a structure in which a plurality of first batteries and a plurality of first spacers are alternately stacked in the first direction; The second battery block has a structure in which a plurality of second batteries and a plurality of second spacers are alternately stacked in the first direction, wherein: The first spacer and the second spacer are integrally formed via a first connecting portion, An inter-block side rail for pressing the first battery block and the second battery block together in the first direction is arranged at the first connection portion.

2. The battery pack according to claim 1, characterized in that: First end plates are disposed at both ends of the first battery block in the first direction. Second end plates are disposed at both ends of the second battery block in the first direction. The inter-block side rail presses the first battery block in the first direction via the first end plate, and presses the second battery block in the first direction via the second end plate.

3. The battery pack according to claim 2, characterized in that: The first end plate and the second end plate are continuously formed via a second connecting portion. The inter-block side rails are arranged at the second connecting portion.

4. The battery pack according to claim 1, characterized in that: The inter-block side rail has an extension portion extending in the first direction and a flange portion extending in a direction perpendicular to the first direction. The extending portion is inserted through the first connecting portion.

5. The battery pack according to claim 2, characterized in that: The inter-block side rails have: an extension portion extending along the first direction; a first flange portion extending at a first end portion of the extending portion in a direction perpendicular to the first direction; A second flange portion extends in a direction perpendicular to the first direction at a second end portion of the extending portion opposite to the first end portion, The first battery block is pressed by the first flange portion and the second flange portion via the first end plate, The second battery block is pressed via the second end plate by the first flange portion and the second flange portion.

6. The battery pack according to claim 3, characterized in that: The inter-block side rails have: an extension portion extending along the first direction; a first flange portion extending at a first end portion of the extending portion in a direction perpendicular to the first direction; A second flange portion extends in a direction perpendicular to the first direction at a second end portion of the extending portion opposite to the first end portion, The extending portion is inserted through the second connecting portion, The first battery block is pressed by the first flange portion and the second flange portion via the first end plate, The second battery block is pressed via the second end plate by the first flange portion and the second flange portion.

7. The battery pack according to any one of claims 4 to 6, characterized in that: A slit is formed in the first connecting portion, The extending portion of the inter-block side rail is inserted through the slit.

8. The battery pack according to any one of claims 3 to 6, characterized in that: A slit is formed in the second connecting portion, The extending portion of the inter-block side rail is inserted through the slit.

9. The battery pack according to any one of claims 1 to 8, characterized in that: The side rails are formed by bending a sheet of metal plate.

10. The battery pack according to any one of claims 4 to 8, characterized in that: The flange portion and the extension portion are connected by welding, riveting or screwing.

11. The battery pack according to any one of claims 1 to 10, characterized in that: The bending strength of the first connection portion is smaller than the bending strength of the first spacer and the second spacer.

12. The battery pack according to any one of claims 2 to 10, characterized in that: The bending strength of the second connection portion is smaller than the bending strength of the first end plate and the second end plate.

13. The battery pack according to any one of claims 1 to 12, characterized in that: The first spacer and the second spacer are formed of resin.

14. The battery pack according to any one of claims 2 to 13, characterized in that: The first end plate and the second end plate are formed of metal or resin.

15. The battery pack according to any one of claims 1 to 14, characterized in that: The battery pack has only two terminals connected to the outside.

Images