Battery pack

Abstract

To provide a battery pack.SOLUTION: A battery pack of the present invention, is a battery pack which houses an electrode body into an inner part of an outer casing formed by a laminate film, and to which a plurality of laminate cells projecting a tub lead from one side and the other side of an outer casing is laminated, comprising: a plurality of structures in which the plurality of tub leads projected from one side and the other side of the outer casing is arranged with a gap to a lamination direction of each laminate cell, and which is arranged to an interval of the adjacent tub leads so as to be arranged; a connection member that is attached to the structure, and electrically connects both tub leads positioned on both sides of the structure; and pressing means of applying a pressure to the plurality of arranged tub leads and the connection member to the lamination direction of them.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a battery pack.

Background Art

[0002] In recent years, research and development have been carried out on secondary batteries that contribute to energy efficiency in order to enable more people to access affordable, reliable, sustainable, and advanced energy. A laminated secondary battery generally forms one battery cell by laminating a plurality of configurations of a positive electrode, an electrolyte, and a negative electrode. The development of this laminated secondary battery is in progress as it is advantageous for increasing the capacity or voltage by lamination.

[0003] For example, Patent Document 1 below describes a battery having a structure in which laminated battery elements are housed inside an exterior body made of a composite film of metal and resin, and the exterior body is sealed. In this battery, the surplus portions of the upper and lower composite films protruding from the outer periphery of the exterior body are joined by heat fusion to seal the exterior body. Further, a configuration is adopted in which a conductive member is passed through a portion joined by heat fusion and the conductive member is connected to the ground.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Since a laminated secondary battery has a structure in which a plurality of battery elements are laminated, a plurality of tab leads led out from each battery element are arranged at intervals. In the conventional structure, a structure in which adjacent tab leads are joined via a bus bar by welding is known. In this structure, there are many welding points of the bus bar, making connection difficult and disassembly not easy, which is a problem. Furthermore, because the tab leads are spaced apart, there are many gaps around the tab leads and their leads. When considering the overall structure of the battery, having many gaps is disadvantageous for miniaturization and results in a lot of wasted space, so it cannot be said that the structure achieves a sufficiently high energy density as a battery.

[0006] The present invention has been made in view of the above circumstances, and aims to provide a battery pack that simplifies the structure of the tab lead connection portion, eliminates unnecessary space, and achieves miniaturization as a battery, thereby increasing energy density. This will ultimately contribute to energy efficiency. [Means for solving the problem]

[0007] (1) The first embodiment of the battery pack is a battery pack in which an electrode body is housed inside an outer casing made of laminate film, and a plurality of laminate cells are stacked, each having tab leads protruding from one side and the other side of the outer casing, wherein the tab leads protruding from one side and the other side of the outer casing are arranged in a plurality of arrangements with gaps between them in the stacking direction of the laminate cells, and the battery pack is characterized by comprising a plurality of structures arranged in the gaps between the arranged and adjacent tab leads, connecting members provided on the structures to electrically connect the tab leads located on both sides of the structures, and pressurizing means for pressurizing the plurality of arranged tab leads and the connecting members in the stacking direction.

[0008] By applying pressure in the stacking direction to the portion where the tab leads and structures are stacked using a pressurizing means, a structure in which the tab leads and structures are densely stacked without gaps can be obtained. Since connecting members are attached to each structure, tab leads located on both sides of the structure can be electrically connected to each other. Furthermore, since the connecting members are reliably in contact with the tab leads by the pressurizing means, a structure can be obtained in which adjacent tab leads are electrically and reliably joined to each other with low resistance via the structure. By placing structures in the gaps between tab leads and providing connecting members to the structures, electrical connection of the tab leads can be realized in a space-saving configuration, contributing to the miniaturization of batteries.

[0009] (2) In the second embodiment of the battery pack, it is preferable that the pressurizing means is an end plate located on both sides of the arrangement direction of the arranged tab leads and pressurizing the plurality of tab leads and the structure in the stacking direction, and that the laminate cell is modularized by the end plate.

[0010] By sandwiching a laminated structure of multiple tab leads and multiple structural elements between end plates and applying pressure, a structure in which the tab leads and structural elements are densely laminated without gaps can be obtained using the end plates. By sandwiching and applying pressure with end plates, the connection between tab leads via connecting members can be reliably established. The laminate cell is modularized by incorporating end plates.

[0011] (3) In the third embodiment of the battery pack, it is preferable that a spacer is placed between the structure and the end plate.

[0012] By using a spacer placed between the structure and the end plate, a structure can be obtained in which the tab leads and the structure are densely stacked without any gaps. By using the spacer and applying pressure, the connection between the tab leads via the connecting member can be made secure.

[0013] (4) In the fourth embodiment of the battery pack, it is preferable that at least one of the plurality of structures is equipped with an electrical device.

[0014] By equipping the structure with electrical equipment, it becomes possible to equip the structure with electrical equipment electrically connected to the tab lead, allowing power to be supplied to the electrical equipment from the tab lead, and enabling the use of the electrical equipment. For example, if the electrical equipment is a voltage sensor, it can measure the potential of the laminated cell.

[0015] (5) In the fifth embodiment of the battery pack, it is preferable that the laminate film comprises an inner resin film, a metal film, and an outer resin film, and that at least one of the plurality of structures is equipped with an electrical device, and that the electrical device is electrically connected to the metal film.

[0016] By equipping the laminate film with electrical devices that are electrically connected to the metal film, electrical conductivity between the electrical devices and the metal film becomes possible. The metal film can be used as part of the wiring for electrical devices, which can simplify the wiring process.

[0017] (6) The sixth form of the battery pack can adopt a configuration in which at least one of the plurality of structures is equipped with a refrigerant flow path.

[0018] By providing a structure with a refrigerant flow path, the tab leads can be cooled through the structure. The tab leads are parts that can become hot during battery use, and being able to cool the tab leads has the effect of suppressing the temperature rise of the battery pack. Furthermore, suppressing the temperature rise of the battery pack prevents the output of the battery pack from being limited by heat, which leads to the realization of the battery pack's original conductivity performance.

[0019] (7) The seventh embodiment of the battery pack preferably comprises a plurality of structures including a first electrical device and a second electrical device, wherein the structure disposed between the structure containing the first electrical device and the structure containing the second electrical device is made of resin and is a structure equipped with a refrigerant flow path.

[0020] The tab lead is a part that easily generates heat, and if the structure adjacent to the tab lead is equipped with a first electrical device and a second electrical device, the heat generated from the first and second electrical devices will also be added. Therefore, being able to cool the structure between the first and second electrical devices with a coolant allows for efficient cooling of the tab lead and its surroundings, as well as the heat-generating parts including the first and second electrical devices.

[0021] (8) In the eighth embodiment of the battery pack, it is preferable that the connecting member provided in the structure having the refrigerant flow path functions as a cooling member for the first electrical equipment and the second electrical equipment located on both sides of the structure.

[0022] The connection member provided in the structure having the refrigerant flow path conducts the tab leads on both sides thereof and functions as a cooling member for cooling these tab leads. Further, cooling of the first electrical device and the second electrical device provided on both sides of the structure having the refrigerant flow path is also performed.

Effect of the Invention

[0023] According to the present invention, by pressing the portion where the tab lead and the structure are laminated in the lamination direction by a pressing means, a battery pack in which the tab lead and the structure are laminated closely without a gap can be provided. Since the connection member is attached to each structure, the tab leads located on both sides of the structure can be electrically connected. Further, since the connection member is surely brought into contact with the tab lead by the pressing means, a battery pack in which the adjacent tab leads are surely electrically joined through the structure can be provided.

Brief Description of the Drawings

[0024] [Figure 1] Configuration diagram showing a laminated portion of one tab lead in the battery pack of the first embodiment. [Figure 2] Configuration diagram showing a laminated portion of the other tab lead in the battery pack of the first embodiment. [Figure 3] Shows components applied to the battery pack, (a) is a configuration diagram of a structure having a refrigerant flow path, (b) is a configuration diagram showing a structure having a voltage sensor, (c) is a configuration diagram showing one spacer, and (d) is a configuration diagram showing the other pack. [Figure 4] Configuration diagram showing a laminated portion of one tab lead in the battery pack of the second embodiment. [Figure 5] Configuration diagram showing a laminated portion of the other tab lead in the battery pack of the second embodiment. [Figure 6] Configuration diagram showing a laminated portion of one tab lead in the battery pack of the third embodiment. [Figure 7] Configuration diagram showing an example of a conventional battery pack. [Figure 8]Figure 7 shows the components applied to the battery pack, with (a) being a diagram of the laminated cell configuration, (b) being a diagram of the busbar configuration, and (c) being a diagram of the voltage sensor configuration. [Figure 9] A plan view of a laminate cell applied to a battery pack of the fourth embodiment. [Figure 10] A diagram showing the circuitry applied to a conventional laminate cell. [Figure 11] A diagram showing the circuit applied to a laminate cell used in the battery pack of the fourth embodiment. [Modes for carrying out the invention]

[0025] Embodiments of the present invention will be described in detail below with reference to the attached drawings. Note that, for convenience, the drawings used in the following description may show enlarged versions of key features to make them easier to understand.

[0026] The battery pack A according to the first embodiment is a battery pack in which a plurality of electrode bodies 1 are housed inside an outer casing 2 made of laminate film, and a plurality of laminate cells 5, each with tab leads protruding from one side and the other side of the outer casing 2, are stacked in the thickness direction. Figure 1 shows the schematic cross-sectional structure of the stacked portion on the side where one tab lead protrudes in a stacked battery pack A, and Figure 2 shows the schematic cross-sectional structure of the stacked portion on the side where the other tab lead protrudes in a stacked battery pack A.

[0027] The electrode body 1 may have a structure in which a positive electrode and a negative electrode are stacked with an electrolytic layer in between, or a structure in which multiple positive and negative electrodes are stacked with a separator or the like and contain an electrolyte. The positive electrode and negative electrode are provided with a current collector layer (not shown), and the tab lead 3 on the positive electrode side or the tab lead 6 on the negative electrode side, which are connected to these current collector layers, protrude to the outside of the outer casing. In the configuration shown in Figures 1 and 2, six laminate cells 5 are laminated with a cushioning material 4 in between, such that the tab leads 3 on the negative electrode side and the tab leads 6 on the positive electrode side are alternately arranged in the lamination direction (left-right direction in Figure 1). Therefore, in the lamination direction of the laminate cells 5, the tab leads 3 and tab leads 6 are arranged alternately with a gap corresponding to the thickness of the laminate cell 5 and the thickness of the cushioning material 4.

[0028] The outer casing 2, as an example, consists of a laminate film with a multi-layer structure in which an inner resin film, a metal film, and an outer resin film are laminated together. For example, the electrode body 1 has a rectangular shape in plan view. In this case, the outer casing 2 is a rectangular bag in plan view, with a tab lead 3 protruding a predetermined length from one end of the outer casing 2 in the longitudinal direction and a tab lead 6 protruding a predetermined length from the other end.

[0029] The outer casing 2 has a structure with a certain thickness, consisting of multiple electrode bodies 1 stacked inside, but the protruding portions of the tab leads 3 and 6 are thinner than the overall thickness of the outer casing 2. At the protruding portion of the tab lead 3, the edges of the laminate film that make up the front and back surfaces of the outer casing 2 are tightly attached to sandwich the tab lead 3 from both sides in its thickness direction and are integrated by methods such as welding. The base end of the tab lead 3 is covered so as to be sandwiched between the edges of the laminate film which is integrated by welding, but the tip end of the tab lead 3 protrudes outward from the edge of the laminate film. Although not shown in Figure 1, the base end of the tab lead 3 is connected to the current collector layer provided on the electrode body 1 on the inside of the outer casing 2. Furthermore, the structure of the part where the tab lead 6 is sandwiched and welded to the edge of the laminate film is the same as the structure of the welded part of the tab lead 3.

[0030] Figure 1 primarily depicts the stacked portion of the multiple tab leads 3 and 6 and their surroundings, so the internal structure of the laminate cell 5 is omitted. Also, Figure 1 shows a simplified representation of the portion where the laminate films constituting the front and back surfaces of the outer casing 2 are close to each other and overlap the front and back surfaces of the tab leads 3 and 6. The outer casing 2 has a front surface portion 2A and a back surface portion 2B that cover the front and back surfaces of the electrode body 1, an inclined portion 2C whose ends approach the tab lead 3 or tab lead 6, and a covering portion 2D that corresponds to the portion that covers both sides of the tab lead 3 or both sides of the tab lead 6. The outer casing 2 is sealed by welding the covering portion 2D of these laminate films and its surroundings.

[0031] Figure 1 illustrates a structure in which six laminate cells 5 are stacked in the thickness direction (left-right direction in Figure 1). Also in Figure 1, the negative electrode tab leads 3 and the positive electrode tab leads 6 are arranged alternately from left to right. In Figure 1, from left to right, the first structure 8 is interposed between the first tab lead 3 and the second tab lead 6, the second structure 9 is interposed between the second tab lead 6 and the third tab lead 3, the third structure 10 is interposed between the third tab lead 3 and the fourth tab lead 6, the fourth structure 11 is interposed between the fourth tab lead 6 and the fifth tab lead 3, and the fifth structure 12 is interposed between the fifth tab lead 3 and the sixth tab lead 6.

[0032] The first structure 8 is made of insulating resin and comprises a block-shaped base 8A sandwiched between the first tab lead 3 and the second tab lead 6, and a block-shaped extension 6B extending from the base 8A toward the inclined portion 2C of the laminate cell 5. The covering portion 2D of the laminate film that sandwiches the tab leads 3 and 6 has a certain length in the direction perpendicular to the plane of the paper in Figure 1, so the base 8A and the extension 8B also have a certain length in the direction perpendicular to the plane of the paper in Figure 1. The extension 8B is shaped to occupy the space from near the tip of the covering portion 2D of the laminate film to near the inclined portion 2C of the laminate film.

[0033] In the first structure 8, a connecting member (connecting wiring) 15 is incorporated so as to penetrate the base 8A in the thickness direction, and a voltage sensor (electrical device) 16 connected to this connecting member 15 is incorporated inside the base 8A. Both ends of the connecting member 15 are exposed on both the left and right end faces of the base 8A in Figure 1, and are electrically connected to tab leads 3 and 6 located on both the left and right sides of the base 8A by electrode portions (not shown) provided on the exposed portions. The third structure 10 and the fifth structure 12 have the same structure as the first structure 8, and each incorporates a connecting member 15 and a voltage sensor 16, respectively. The connecting member 15 incorporated in the third structure 10 is electrically connected to tab leads 3 and 6 located on the left and right sides of the third structure 10. The connecting member 15 incorporated in the fifth structure 12 is electrically connected to tab leads 3 and 6 located on the left and right sides of the fifth structure 12.

[0034] The second structure 9 has a base 9A and an extension 9B made of insulating resin, which are substantially the same shape as the base 8A and extension 8B provided in the first structure 8. In the second structure 9, a refrigerant flow path 17 is formed in the base 9A, which penetrates the central part of the base 9A in the direction perpendicular to the plane of the paper in Figure 1. A refrigerant circulation pipe (not shown) is connected to this refrigerant flow path 17. This configuration allows for the cooling of the second structure 9 and its surroundings by flowing a liquid refrigerant, such as water, from this refrigerant circulation pipe into the refrigerant flow path.

[0035] The base 9A of the second structure 9 incorporates a connecting member 18 that forms a U-shape in the cross-section shown in Figure 1. The connecting member 18 has an electrode portion 18A exposed on the side of the base 9A closest to the first structure 8, a conductive portion 18B penetrating the base 9A in the thickness direction, and an electrode portion 18C exposed on the side of the base 9A closest to the third structure 10. The connecting member 18 incorporated into the second structure 9 is electrically connected to the tab leads 3 and 6 located on both sides of the second structure 9 in the thickness direction. The fourth structure 11 has a structure equivalent to that of the second structure 9. It has a base portion 11A and an extension portion 11B, with a refrigerant flow path 17 formed in the base portion 11A and a connecting member 18 incorporated therein. The connecting member 18 is electrically connected to tab leads 3 and 6 located on both sides of the fourth structure 11 in the thickness direction.

[0036] As explained above, the structures in Figure 1 are arranged in the following order from left to right: tab lead 3, first structure 8, tab lead 6, second structure 9, tab lead 3, third structure 10, tab lead 6, fourth structure 11, tab lead 3, fifth structure 12, and tab lead 6. In the laminated structure shown in Figure 1, the negative electrode plate 20 is positioned on the outer side in the stacking direction of the leftmost tab lead 3, and the positive electrode plate 21 is positioned on the outer side in the stacking direction of the rightmost tab lead 6. Spacers 22 and 23 are positioned on the outer side in the stacking direction of the negative electrode plate 20 and the positive electrode plate 21, and these spacers 22 and 23 are provided with pressurizing means (not shown) that apply a pressing force in a direction that brings them closer together. A negative electrode terminal 26 is formed on the outer side of the negative electrode plate 20, and a positive electrode terminal 27 is formed on the outer side of the positive electrode plate 21.

[0037] As shown in Figure 1, end plates 24 and 25 are positioned on the outer side in the stacking direction of the stacked six laminate cells 5. Furthermore, the outer side of the end plates 24 and 25 is provided with the peripheral wall of a housing container for housing the battery pack A of this embodiment. As an example, the pressurizing means can be an elastic body that contacts the peripheral wall of the aforementioned containment container and applies a pressurizing force to the spacers 22 and 23, or an intervening member that is placed between the peripheral wall and the container. The spacers 22 and 23 are located on both sides of the arrangement direction of the tab leads 3 and 6, which are arranged as described above, and press the multiple tab leads 3 and 6 and the structures 8 to 12 in the stacking direction, causing them to adhere closely to each other.

[0038] Figure 2 shows the schematic cross-sectional structure of the other tab lead of battery pack A, where the tab leads are stacked. The structure of this stacked section is similar to the structure of one of the stacked sections of battery pack A, which was explained earlier using Figure 1. In the stacked section shown in Figure 2, spacer 29, tab lead 6, sixth structure 30, tab lead 3, seventh structure 31, tab lead 6, eighth structure 32, tab lead 3, ninth structure 33, tab lead 6, tenth structure 34, tab lead 3, and spacer 35 are arranged from left to right. The sixth structure 30, the eighth structure 32, and the tenth structure 34 have the same structure as the second structure 9 described earlier. Structures 30, 32, and 34 are arranged in the opposite orientation to structures 9 and 11 shown in Figure 1.

[0039] The sixth structure 30 has a base 30A and an extension 30B, a refrigerant flow path 17, and a connecting member 18. The eighth structure 32 has a base 32A and an extension 32B, a refrigerant flow path 17, and a connecting member 18. The tenth structure 34 has a base 34A and an extension 34B, a refrigerant flow path 17, and a connecting member 18. The seventh structure 31 and the ninth structure 33 have the same structure as the first structure 8 described earlier. The seventh structure 31 has a base portion 31A and an extension portion 31B, and includes a connecting member 15 and a voltage sensor 16. The ninth structure 33 has a base portion 33A and an extension portion 33B, and includes a connecting member 15 and a voltage sensor 16.

[0040] As shown in Figure 2, six laminate cells 5 are stacked, and end plates 24 and 25 are positioned on the outer side in the stacking direction. Furthermore, the peripheral walls of a housing container for housing the battery pack A of this embodiment are provided on the outside of the end plates 24 and 25. The end plates 24 and 25 support the stacked laminate cells 5 from both sides in the stacking direction via a cushioning material 4. Multiple laminate cells 5 are modularized with these end plates 24 and 25. The outer surfaces of the spacers 29 and 35 are provided with pressurizing means that apply a pressing force in a direction that brings them closer together. On the surface of spacer 29 facing the tab lead 6, a protrusion 29a is formed that can be pressed against the tab lead 6. This protrusion 29a allows the tab lead 6 to be properly pressed against the connecting member 18 on the side of the base 30A without any gaps. On the surface of spacer 35 facing the tab lead 3, a protrusion 35a is formed that can be pressed against the tab lead 3. This protrusion 35a allows the tab lead 3 to be properly pressed against the connecting member 18 on the side of the base 34A without any gaps. As an example, the pressurizing means can be an elastic body or an intervening member that contacts the peripheral wall of the aforementioned containment container and applies a pressurizing force to the spacers 29 and 35. Figure 3 shows the first structure 8, the second structure 9, and spacers 22 and 23 separated from battery pack A.

[0041] If the battery pack A has the structure shown in Figures 1 to 3, then by applying pressure in the stacking direction to the portion where the tab leads 3 and 6 and structures 8 to 12 are stacked using a pressure means, a structure can be obtained in which multiple tab leads 3 and 6 and structures 8 to 10 are densely stacked without gaps. Furthermore, since connecting members 15 are provided on structures 8, 10, 12, 31, and 33, and connecting members 18 are provided on structures 9, 11, 30, 32, and 34, a series structure can be adopted in which the tab leads 3 on the negative electrode side and the tab leads 6 on the positive electrode side of the six stacked laminate cells 5 are sequentially connected, thereby enabling the construction of a battery pack A equipped with a negative electrode terminal 26 and a positive electrode terminal 27. The pressurizing means ensures that the connecting members 15 and 18 and the tab leads 3 and 6, as well as the negative electrode plate 20 and the positive electrode plate 21, are reliably in contact at their respective contact points. As a result, a battery pack A is obtained in which adjacent tab leads 3 and 6 are reliably electrically joined via the aforementioned structure. By joining them using the pressurizing means, low-resistance connections can be made at each contact point.

[0042] In battery pack A, structures 9, 11, 30, 32, and 34 equipped with a refrigerant flow path 17 are provided, allowing the tab leads 3 and 6 to be cooled via structures 9, 11, 30, 32, and 34. Tab leads 3 and 6 are parts that can become hot during use of the battery pack, and being able to cool the tab leads 3 and 6 has the effect of suppressing the temperature rise of battery pack A. Furthermore, suppressing the temperature rise of battery pack A leads to the reduction of output limitations due to heat in battery pack A. Therefore, battery pack A can fully demonstrate its inherent battery performance.

[0043] In the configuration shown in Figure 1, voltage sensors 16, which are electrical devices, are placed on both sides of the stacking direction of the second structure 9. Therefore, by utilizing the refrigerant flow path 17 located near the voltage sensors 16, which could be heat sources, the two voltage sensors 16 and their surroundings can be efficiently cooled. Since voltage sensors 16 are positioned on both sides of a single refrigerant flow path 17, one voltage sensor 16 can be referred to as the first electrical device, and the other voltage sensor 17 can be referred to as the second electrical device. The refrigerant flow path 17, sandwiched between these two electrical devices (voltage sensors 16, 16), functions as a cooling element for the two electrical devices.

[0044] Since battery pack A incorporates multiple voltage sensors 16, if an abnormality occurs in any of the laminate cells 5, such as a voltage drop, the abnormality in the laminate cell 5 can be reliably detected. Furthermore, the space between tab leads 3 and 6 was not particularly utilized in conventional structures and remained empty space. In contrast, battery pack A effectively utilizes this space by using multiple structures to provide a refrigerant flow path 17 and a voltage sensor 16, resulting in a configuration with less wasted space. Therefore, battery pack A of this embodiment has less wasted space than conventional battery packs and can be made smaller.

[0045] Figure 7 is a diagram showing an example of a conventional battery pack equipped with a voltage sensor and busbars. In battery pack B, the configuration in which laminate cells 5 are stacked such that the positive electrode tab leads 3 and the negative electrode tab leads 6 are alternately arranged in the stacking direction is the same as in battery pack A of the first embodiment described above. The configuration in which the outer casing 2 is made of laminate film is similar, and the configuration in which the negative electrode tab lead 3 protrudes a predetermined length from one end in the longitudinal direction of the outer casing 2 and the positive electrode tab lead 6 protrudes a predetermined length from the other end is also similar.

[0046] Battery pack B has a structure in which eight laminate cells 5 are stacked in the thickness direction, and tab leads 3 and tab leads 6, which are arranged alternately along the stacking direction of the laminate cells 5, are joined by bus bars 40. Both ends of the bus bars 40 are welded to adjacent tab leads 3 and tab leads 6. Therefore, in the battery pack B shown in Figure 7, three busbars 40 are used for the connection on the right side of the structure in which eight laminated cells 5 are stacked, and four busbars 40 are used for the connection on the left side of the structure in which eight laminated cells 5 are stacked. Thus, a total of seven busbars 40 are used, and assuming that both ends are welded, the structure requires 14 welding points. Furthermore, welding the negative terminal 41 to one tab lead 3 and the positive terminal 42 to the other tab lead 6 required two additional welding points. Consequently, the conventional battery pack B had many welding points, making the manufacturing of the battery pack B itself extremely difficult.

[0047] Furthermore, in battery pack B, when eight voltage sensors 43 were provided, the voltage sensors 43 were connected to tab leads 3 and tab leads 6 located at both ends of a single laminate cell 5 via harness wiring 44. As a result, it was necessary to provide at least eight sets of harness wiring 44 in battery pack B, which resulted in a problem of complex wiring. In contrast, in battery pack A, as explained based on Figures 1 to 3, the busbar 40 is unnecessary, welding is not required, and the wiring to the voltage sensor can be significantly simplified. Furthermore, in battery pack B, the space between tab leads 3 and 6 was unused, and it was necessary to place the voltage sensor 43 and harness wiring 44 outside the laminate cell 5, resulting in a large and complex battery structure. In contrast, in battery pack A, the space between tab leads 3 and 6 is used to place the connecting members 15 and 18 and the voltage sensor 16, thus simplifying the structure and eliminating wasted space, resulting in a smaller overall size.

[0048] Figures 4 and 5 are schematic cross-sectional views showing a battery pack D of a second embodiment according to the present invention. In the battery pack D, the structure in which six laminate cells 5 are stacked in the thickness direction is the same as the structure of the first embodiment described above. The battery pack D shown in Figures 4 and 5 has a similar structure in which, from left to right, the spacer 22, negative electrode plate 20, tab lead 3, first structure 8, tab lead 6, second structure 9, tab lead 3, third structure 10, tab lead 6, fourth structure 11, tab lead 3, fifth structure 12, tab lead 6, positive electrode plate 21, and spacer 23 are arranged in the same order. The difference between the structure of the second embodiment and the structure of the first embodiment is that the end plate 24A extends to the outside of the spacer 22, and the end plate 25A extends to the outside of the spacer 23.

[0049] In the second embodiment, the end plate 24A is located outside the spacer 22, the end plate 25A is located outside the spacer 23, and the configuration is characterized by a pressurizing means that pressurizes the spacers 22 and 23. The end plates 24A and 25A pressurize the multiple tab leads and structures interposed between the spacers 22 and 23, causing them to tightly adhere to each other and improving the electrical connectivity of each contact. As shown in the second embodiment, the end plates 24A and 25A may also be used as pressurizing means. Furthermore, the battery pack B of the second embodiment can achieve the same effects and advantages as the battery pack A of the first embodiment.

[0050] Figure 6 is a schematic cross-sectional view showing a battery pack E according to a third embodiment of the present invention. Figure 6 shows a schematic cross-section of battery pack E, which corresponds to the schematic cross-sectional structure of the laminated portion on the side where one tab lead protrudes in battery pack A shown in Figure 1. In the battery pack E, the structure of the laminate cell 5 having tab leads 3 and 6 is similar, but eight laminate cells 5 are stacked in the thickness direction with cushioning material 4 in between.

[0051] In the structure shown in Figure 6, the following components are arranged from left to right: spacer 22, negative electrode plate 20, tab lead 3, first structure 51, tab lead 3, second structure 52, tab lead 6, third structure 53, tab lead 6, fourth structure 54, tab lead 3, fifth structure 55, tab lead 3, sixth structure 56, tab lead 6, seventh structure 57, tab lead 6, positive electrode plate 21, and spacer 23. The first structure 51, the third structure 53, the fourth structure 54, the fifth structure 55, and the seventh structure 57 have the same structure as the second structure 9 of the first embodiment. The second structure 52 and the sixth structure 56 have the same structure as the first structure 8 of the first embodiment.

[0052] The first structure 51 has a base 51A and an extension 51B, and has a refrigerant flow path 17 and a connecting member 18. The third structure 53 has a base 53A and an extension 53B, and has a refrigerant flow path 17 and a connecting member 18. The fourth structure 54 has a base 54A and an extension 54B, and has a refrigerant flow path 17 and a connecting member 18. The fifth structure 55 has a base 55A and an extension 55B, and has a refrigerant flow path 17 and a connecting member 18. The seventh structure 57 has a base 57A and an extension 57B, and has a refrigerant flow path 17 and a connecting member 18. The second structure 52 has a base 52A and an extension 52B, and includes a connecting member 15 and a voltage sensor 16. The sixth structure 56 has a base 56A and an extension 56B, and includes a connecting member 15 and a voltage sensor 16.

[0053] In the battery pack E shown in Figure 6, the connecting member 18 of the first structure 51 connects the tab leads 3, 3 on the negative electrode side of the laminate cells 5, 5 located on either side thereof. The connecting member 15 of the second structure 52 connects the tab leads 3 and 6 of the laminate cells 5 and 5 located on both sides thereof. The connecting member 18 of the third structure 53 connects the tab leads 6, 6 on the positive electrode side of the laminate cells 5, 5 located on either side thereof. The connecting member 15 of the fourth structure 54 connects the tab leads 3 and 6 of the laminate cells 5 and 5 located on either side thereof.

[0054] The connecting member 18 of the fifth structure 55 connects the tab leads 3, 3 on the negative electrode side of the laminate cells 5, 5 located on either side thereof. The connecting member 15 of the sixth structure 56 connects the tab leads 3 and 6 of the laminate cells 5 and 5 located on either side thereof. The connecting member 18 of the seventh structure 57 connects the tab leads 6, 6 on the negative electrode side of the laminate cells 5, 5 located on either side thereof. Note that, in the battery pack E shown in Figure 6, the explanation of the configuration of the tab lead on the opposite side and the structure provided between each tab lead will be omitted.

[0055] The battery pack E described above is a battery in which the tab leads 3, 3 or tab leads 6, 6 on the same polarity side of two adjacent laminate cells 5 in the stacking direction are connected to each other to form a parallel structure. Because this battery pack E connects adjacent laminate cells 5, 5 in parallel, it has the advantage of being able to achieve a larger capacity, although its output voltage is lower than that of the aforementioned battery pack A. The other components are the same as those of the battery pack A in the first embodiment, and the same effects and benefits as those of the battery pack A in the first embodiment can be obtained.

[0056] As clarified by the structure shown in Figure 6, when stacking laminate cells 5, by changing the stacking direction of the laminate cells 5, reusing the same structure as the series-structured battery pack A of the first embodiment, and changing the installation position, it is possible to accommodate the parallel-structured battery pack E shown in Figure 6. In the battery pack, the number of laminate cells 5 stacked can be arbitrarily selected, and the aforementioned structure can be applied to either a series connection structure or a parallel connection structure corresponding to that number of stacks. Furthermore, the structure provided between the tab leads may be either a structure with a voltage sensor 16 or a structure with a refrigerant flow path 17. If necessary, the structure with a voltage sensor 16 may be applied to all structures, or the structure with a refrigerant flow path 17 may be applied to all structures. The number of each structure to be applied can also be arbitrarily selected.

[0057] Figure 9 is an explanatory diagram showing a laminate cell applied to a battery pack according to the third embodiment of the present invention. The laminate cell 60 shown in Figure 9 has the same configuration as the laminate cell 5 of the first embodiment, in that the internal electrode body 1 is covered by the outer casing 62. The outer casing 62 has a front surface 62A and a back surface (not shown), an inclined portion 62C whose ends approach the negative electrode tab lead 63 or the positive electrode tab lead 66, and a covering portion 62D which corresponds to the portion that covers both sides of the tab lead 3 or both sides of the tab lead 6. Similar to the laminate cell 5 of the first embodiment, the outer casing 62 is sealed by welding the covering portion 62D of these laminate films and its surroundings.

[0058] A distinctive feature of the laminate cell 60 is that holes 67 and 68 are formed in a part of the outer casing 62 for connecting to the metal film 62E within the laminate film that constitutes the outer casing 62. One hole 67 is formed at a position close to the tab lead 63 on the negative electrode side and opens into the metal film within the laminate film, while the other hole 68 is formed at a position close to the tab lead 66 on the positive electrode side and opens into the metal film within the laminate film.

[0059] Figure 10 is a schematic diagram showing a circuit in which a voltage sensor 43 is connected to one laminate cell 5 via harness wiring 44 in the conventional battery pack B shown in Figure 7. In contrast, as shown in Figure 9, in a configuration where holes 67 and 68 are provided in the outer casing 62, as shown in Figure 11, one end of the wiring 65 is connected to the metal film 62E inside the laminate film via hole 67, and the other end of the wiring 65 is connected to one of the connection terminals of the voltage sensor 69. Also, one end of the wiring 64 is connected to the metal film 62E inside the laminate film via hole 68, and the other end of the wiring 64 is connected to the positive electrode tab lead 66. The other connection terminal of the voltage sensor 69 is connected to the other tab lead 63 of the laminate cell 5 by wiring 70. In Figure 11, the voltage sensor 69 is depicted at a location away from the tab lead 63 for better visibility of the wiring; however, the voltage sensor 69 is actually installed inside the structure shown in Figure 1, etc.

[0060] By adopting the configuration shown in Figure 11, most of the harness wiring 44 required in the conventional structure shown in Figure 10 can be replaced with metal film 62E, thereby simplifying the harness wiring 44. In the configuration shown in Figure 11, the metal film 62E within the laminate film can be used as part of the harness wiring to operate the voltage sensor 65, and the harness wiring when configuring the battery pack can be simplified. [Explanation of symbols]

[0061] A, D, E... Battery packs, 1...electrode body, 2... Exterior body, 3... Negative side tab lead, 5... Laminated cell, 6... Positive side tab lead, 8, 51... First structure, 9, 52... Second structure, 10, 53... Third structure, 11, 54…The fourth structure, 12, 55…the fifth structure, 15…Connecting members, 16…Voltage sensor (electrical equipment), 17... Refrigerant flow path, 18…Connecting members, 22, 23... Spacers, 24, 24A, 25, 25A... End plates, 29...Spacer, 30, 56… The sixth structure, 31, 58... The seventh structure, 32... The eighth structure, 33... The ninth structure, 34...The tenth structure, 35...Spacer, 60... Laminated cell, 62... Exterior body, 62A...Inner resin film, 62B...Outer resin film, 62E... Metal film, 62E... Metal film, 63... Negative side tab lead, 65...Voltage sensor, 66... ​​Positive side tab lead, 67, 68...hole, 69…Voltage sensor (electrical equipment).

Claims

1. A battery pack comprising multiple laminate cells stacked together, each containing an electrode body housed inside an outer casing made of laminate film, with tab leads protruding from one side and the other side of the outer casing, Multiple tab leads protruding from one side and the other side of the outer casing are arranged with gaps between them in the stacking direction of the laminate cell, A plurality of structures arranged in the gaps between adjacent tab leads, A connecting member provided in the structure and electrically connecting the tab leads located on both sides of the structure, The system comprises a plurality of tab leads arranged in a row and a pressurizing means for pressurizing the connecting member in the stacking direction thereof, The plurality of structures are battery packs comprising a first electrical device and a second electrical device, wherein the structure disposed between the structure comprising the first electrical device and the structure comprising the second electrical device is made of resin and is a structure equipped with a refrigerant flow path.

2. The battery pack according to claim 1, wherein the pressurizing means is an end plate located on both sides of the arrangement direction of the arranged tab leads and pressurizing the plurality of tab leads and the structure in the stacking direction, and the laminate cell is modularized by the end plate.

3. The battery pack according to claim 2, wherein a spacer is disposed between the structure and the end plate.

4. The battery pack according to any one of claims 1 to 3, wherein at least one of the plurality of structures is equipped with an electrical device.

5. The battery pack according to any one of claims 1 to 4, wherein the laminate film comprises an inner resin film, a metal film, and an outer resin film, and at least one of the plurality of structures is equipped with an electrical device, and the electrical device is electrically connected to the metal film.

6. The battery pack according to any one of claims 1 to 5, wherein at least one of the plurality of structures is provided with a refrigerant flow path.

7. The battery pack according to claim 1, wherein the connecting member provided in the structure having the refrigerant flow path functions as a cooling member for the first electrical device and the second electrical device, which are located on both sides of the structure.

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