Cell stacks and battery modules

Abstract

To provide a cell lamination body which has a volumetric efficiency enhanced.SOLUTION: In a cell lamination body, a plurality of battery cells having an electrode body, a laminate outer casing sealed into an internal part so as to cover the electrode body, and at least one fixing tape of an inner side fixing tape wound in a peripheral direction to an outer peripheral surface of the electrode body in an inner side of the laminate outer casing and an outer side fixing tape wound in the peripheral direction to the outer peripheral surface of the laminate outer casing are laminated. In the case where a direction in which the plurality of battery cells are laminated is defined as a lamination direction, the fixing tape is wound so that positions of winding of the fixing tape do not overlap with each other in the lamination direction in both of at least a pair of adjacent battery cells.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a cell laminate and a battery module.

Background Art

[0002] Conventionally, battery cells in which electrode bodies in which a plurality of positive electrodes, negative electrodes, and separators are laminated are bundled with a tape have been studied.

[0003] For example, Patent Document 1 includes a laminate in which a positive electrode and a negative electrode are alternately laminated via a separator, and a tape for fixing the laminate. The tape has a pair of flat attachment portions provided at both ends and attached to both outermost layers of the laminate, respectively, and an intermediate portion located between the pair of flat attachment portions and attached to the side edge of each layer of the laminate. The flat attachment portion has a tapered shape with a sharp tip, and a secondary battery is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Conventionally, an electrode body constituting a battery and a laminated exterior body covering the electrode body have been fixed by winding a fixing tape around them. The fixing tape includes an inner fixing tape wound around the outer peripheral surface of the electrode body inside the laminated exterior body, and an outer fixing tape wound around the outer peripheral surface of the laminated exterior body. However, when the fixing tape is wound, the thickness of the fixing tape increases, so there is room for improvement in improving the volume efficiency.

[0006] This disclosure is made in view of the above circumstances and aims to provide a cell stack with improved volumetric efficiency and a battery module having the cell stack. [Means for solving the problem]

[0007] The means for solving the above problems include the following embodiments. <1> Electrode body and A laminate outer casing that covers the electrode body and seals it inside, At least one of the fixing tapes, an inner fixing tape wrapped circumferentially around the outer surface of the electrode body inside the laminate outer casing, and an outer fixing tape wrapped circumferentially around the outer surface of the laminate outer casing, A cell stack in which multiple battery cells having are stacked, When the direction in which the multiple battery cells are stacked is defined as the stacking direction, A cell stack in which the fixing tape is wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the fixing tape do not overlap in the stacking direction. <2> The aforementioned fixing tape consists only of the inner fixing tape, The inner fixing tape is wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the inner fixing tape do not overlap in the stacking direction. <1> The cell laminate described above. <3> The aforementioned fixing tape consists only of the outer fixing tape, The outer fixing tape is wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the outer fixing tape do not overlap in the stacking direction. <1> The cell laminate described above. <4> The aforementioned fixing tape includes the inner fixing tape and the outer fixing tape, In at least one pair of adjacent battery cells, the inner fixing tape and the outer fixing tape are wrapped around the cells in such a way that the wrapping positions of the inner fixing tape and the outer fixing tape do not overlap in the stacking direction. <1> The cell laminate described above. <5> In one of the battery cells, the fixing tapes are wrapped such that the wrapping position of the inner fixing tape and the wrapping position of the outer fixing tape do not overlap. <4> The cell laminate described above. <6> The fixing tape is wrapped around all adjacent battery cells such that the wrapping positions of the fixing tape do not overlap in the stacking direction. <1> ~ <5> A cell laminate as described in any one of the items. <7> The fixing tape is wrapped around all of the battery cells such that the wrapping positions of the fixing tape do not overlap in the stacking direction. <1> ~ <6> A cell laminate as described in any one of the items. <8> <1> ~ <7> A battery module having a cell stack as described in any one of the items. [Effects of the Invention]

[0008] According to this disclosure, it is possible to provide a cell stack with improved volumetric efficiency, and a battery module having the cell stack. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic perspective view showing one electrode body and an inner fixing tape in a cell laminate according to the first embodiment. [Figure 2] Figure 1 is a schematic side view showing a battery cell in which one electrode body and an internal fixing tape are further enclosed by a laminated outer casing. [Figure 3] This is a schematic side view showing a cell laminate according to the first embodiment. [Figure 4]It is a schematic side view showing a battery cell in which one electrode body and a laminate exterior body in the cell laminate according to the second aspect are fixed by an outer fixing tape. [Figure 5] It is a schematic side view showing a cell laminate according to the second aspect. [Figure 6] It is a schematic side view showing a cell laminate according to the third aspect. [Figure 7] It is a schematic side view showing a cell laminate according to a modification example. [Figure 8] It is a schematic plan view showing a main part of a vehicle. [Figure 9] It is a schematic perspective view of a battery module. [Figure 10] It is a plan view of a state where the upper lid of the battery module is removed. [Figure 11] It is a schematic view of a battery cell housed in a battery module as viewed from the thickness direction.

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments which are an example of the present disclosure will be described. These descriptions and examples are illustrative of the embodiments and do not limit the scope of the invention. In the numerical ranges described step by step in this specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of the numerical range described in other step-by-step descriptions. Also, in the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

[0011] <Cell laminate> The cell laminate according to the embodiment of the present disclosure is a cell laminate in which a plurality of battery cells are laminated. This battery cell has an electrode body, a laminate exterior body that covers the electrode body and is enclosed inside, and at least one fixing tape of an inner fixing tape wound circumferentially around the outer peripheral surface of the electrode body and an outer fixing tape wound circumferentially around the outer peripheral surface of the laminate exterior body on the inner side of the laminate exterior body. Furthermore, when the direction in which multiple battery cells are stacked is defined as the stacking direction, the fixing tape is wrapped around at least one pair of adjacent battery cells in such a way that the wrapping positions of the fixing tape do not overlap in the stacking direction.

[0012] For example, if a battery cell has only an inner fixing tape as a fixing tape, the inner fixing tape is wrapped around at least one pair of adjacent battery cells in such a way that the wrapping positions of the inner fixing tape do not overlap in the stacking direction. Furthermore, if a battery cell has only an outer fixing tape as a fixing tape, the outer fixing tape is wrapped around at least one pair of adjacent battery cells in such a way that the wrapping positions of the outer fixing tape do not overlap in the stacking direction. Furthermore, if the battery cell has an inner fixing tape and an outer fixing tape as fixing tapes, the inner fixing tape and the outer fixing tape are wrapped around at least one pair of adjacent battery cells in such a way that the wrapping positions of the inner fixing tape and the outer fixing tape do not overlap in the stacking direction.

[0013] Conventionally, batteries have been equipped with an electrode body and a laminated outer casing that covers the electrode body, and a cell laminate in which the electrode body and the laminated outer casing are stacked. The electrode body in the cell laminate is then fixed with fixing tape. Examples of fixing tape include an inner fixing tape that is wrapped around the outer surface of the electrode body in the circumferential direction inside the laminated outer casing, and an outer fixing tape that is wrapped around the outer surface of the laminated outer casing in the circumferential direction. However, when fixing tape is wrapped around the cell, the thickness of the tape increases, which in turn increases the overall thickness of the cell laminate, leaving room for improvement in volumetric efficiency.

[0014] In contrast, in the cell stack according to the embodiment of this disclosure, the fixing tape is wrapped around at least one pair of adjacent battery cells in such a way that the wrapping positions of the fixing tape do not overlap in the stacking direction. If the wrapping positions of the fixing tape overlap between adjacent battery cells, the thickness will increase by the equivalent of two layers of fixing tape. However, in the cell stack according to the embodiment of this disclosure, the positions of the fixing tape do not overlap between adjacent battery cells, and the increase in the overall thickness of the cell stack due to the fixing tape can be suppressed. In this way, by suppressing the overlap of the fixing tape, the thickness of the cell stack can be reduced, improving volumetric efficiency and increasing energy density.

[0015] In the cell stack according to the embodiment of this disclosure, as described above, it is sufficient that the fixing tape is wrapped around at least one pair of adjacent battery cells so that the wrapping positions of the fixing tape do not overlap in the stacking direction. However, it is preferable that the fixing tape is wrapped around all adjacent battery cells so that the wrapping positions of the fixing tape do not overlap in the stacking direction. Furthermore, it is even more preferable that the fixing tape is wrapped around all battery cells so that the wrapping positions of the fixing tape do not overlap in the stacking direction.

[0016] • First aspect Hereinafter, one embodiment (the first embodiment) of the cell laminate according to the embodiment of this disclosure will be described with reference to the drawings. The following diagrams are schematic representations, and the size and shape of each part have been exaggerated as appropriate for ease of understanding.

[0017] Figure 1 is a schematic perspective view showing one electrode and an inner fixing tape in a cell laminate according to the first embodiment. Figure 2 is a schematic side view showing a battery cell in which the one electrode and inner fixing tape shown in Figure 1 are further enclosed by a laminate outer casing, and is a side view seen from the side direction of the electrode (the X direction in Figure 1). The electrode body 4 shown in Figures 1 and 2 is formed in a substantially rectangular plate shape. Although not shown in the illustration, the electrode body 4 has a positive electrode, a negative electrode, and a separator interposed between the positive and negative electrodes. The electrode body 4 may also have a structure in which multiple stacked structures having a positive electrode, a negative electrode, and a separator are further stacked in the direction of arrow Y (stacking direction).

[0018] The electrode body 4 has terminals (tabs) 26 on each of its longitudinal sides. In this embodiment, as an example, the terminals 26 are positioned offset to one side from the center in the short direction (arrow X direction) of the battery cell 20.

[0019] Five inner fixing tapes 41-45 are arranged on the outer surface of the electrode body 4, wrapped around it in a circular fashion. Each of the inner fixing tapes 41-45 is wrapped around the four sides of the electrode body 4 that do not have terminals 26. If the electrode body 4 has a structure in which multiple stacked structures, each having a positive electrode, a negative electrode, and a separator, are further stacked in the stacking direction (arrow Y direction), the outer surface is wrapped with the inner fixing tapes 41-45 to bundle the multiple stacked structures together. The electrode body 4, secured by five internal fixing tapes 41-45, is then covered and sealed inside by a laminate film 28, which is an example of a laminate outer casing, as shown in Figure 2. Figure 2 shows a side view of the inside of the laminate film 28.

[0020] Although Figures 1 and 2 show an embodiment in which the electrode body 4 is fixed with five internal fixing tapes 41 to 45, the invention is not limited to this, and the number of internal fixing tapes wrapped around a single electrode body 4 can be one or more.

[0021] The cell stack according to the first embodiment further consists of multiple battery cells, as shown in Figures 1 and 2, stacked together as shown in Figure 3. Figure 3 is a schematic side view of the cell stack according to the first embodiment, and is a side view taken from the side direction of the electrode body (the X direction in Figure 1). Note that Figure 3 shows a side view of the inside of the laminate film.

[0022] As shown in Figure 3, the cell stack 200 has a structure in which three battery cells 20A, 20B, and 20C are stacked. Furthermore, the wrapping positions of the fixing tape do not overlap in the stacking direction between all adjacent battery cells, that is, between adjacent battery cells 20A and 20B, and between adjacent battery cells 20B and 20C. Specifically, the wrapping positions of the inner fixing tapes 41A, 42A, 43A, 44A, and 45A on battery cell 20A and the inner fixing tapes 41B, 42B, 43B, 44B, and 45B on battery cell 20B adjacent to battery cell 20A do not overlap in the stacking direction. Furthermore, the wrapping positions of the inner fixing tapes 41B, 42B, 43B, 44B, and 45B on battery cell 20B and the inner fixing tapes 41C, 42C, 43C, 44C, and 45C on battery cell 20C adjacent to battery cell 20B do not overlap in the stacking direction. Furthermore, the wrapping positions of the fixing tape do not overlap in the stacking direction for any of the battery cells, namely battery cell 20A, battery cell 20B, and battery cell 20C. Specifically, the wrapping positions of the inner fixing tapes 41A, 42A, 43A, 44A, and 45A on battery cell 20A, the inner fixing tapes 41B, 42B, 43B, 44B, and 45B on battery cell 20B, and the inner fixing tapes 41C, 42C, 43C, 44C, and 45C on battery cell 20C do not overlap in the stacking direction. Therefore, in the cell laminate 200 shown in Figure 3, the increase in the overall thickness of the cell laminate caused by the fixing tape can be suppressed. This reduces the thickness of the cell laminate, improves volumetric efficiency, and increases energy density.

[0023] • Second aspect Next, another embodiment (second embodiment) of the cell laminate according to the present disclosure will be described with reference to the drawings.

[0024] Figure 4 is a schematic side view showing a battery cell in a cell stack according to the second embodiment, in which one electrode body and a laminate outer casing are fixed by an external fixing tape. The electrode body 4 shown in Figure 4 has terminals (tabs) 26 on each of its longitudinal sides. The electrode body 4 is covered and sealed inside a laminate film 28, which is an example of a laminate outer casing. Figure 4 shows a side view of the inside of the laminate film 28.

[0025] The electrode body 4 enclosed in the laminate film 28 has five outer fixing tapes 61-65 attached to it so as to wrap around the outer surface of the laminate film 28. Each of the outer fixing tapes 61-65 is wrapped around the four sides of the laminate film 28 where there are no terminals 26. Although Figure 4 shows a configuration in which the laminate film 28 is secured with five external fixing tapes 61-65, the configuration is not limited to this, and one or more external fixing tapes can be wrapped around the laminate film 28.

[0026] The cell stack according to the second embodiment further consists of multiple battery cells, as shown in Figure 4, stacked together as shown in Figure 5. Figure 5 is a schematic side view of the cell stack according to the second embodiment, and is a side view taken from the side of the electrode body. Note that Figure 5 shows a side view of the inside of the laminate film.

[0027] As shown in Figure 5, the cell stack 220 has a structure in which three battery cells 22A, 22B, and 22C are stacked. Furthermore, the wrapping positions of the fixing tape do not overlap in the stacking direction between all adjacent battery cells, that is, between adjacent battery cells 22A and 22B, and between adjacent battery cells 22B and 22C. Specifically, the wrapping positions of the outer fixing tapes 61A, 62A, 63A, 64A, and 65A on battery cell 22A and the outer fixing tapes 61B, 62B, 63B, 64B, and 65B on battery cell 22B adjacent to battery cell 22A do not overlap in the stacking direction. Furthermore, the wrapping positions of the outer fixing tapes 61B, 62B, 63B, 64B, and 65B on battery cell 22B and the outer fixing tapes 61C, 62C, 63C, 64C, and 65C on battery cell 22C adjacent to battery cell 22B do not overlap in the stacking direction. Furthermore, the wrapping positions of the fixing tape do not overlap in the stacking direction for any of the battery cells, namely battery cell 22A, battery cell 22B, and battery cell 22C. Specifically, the wrapping positions of the outer fixing tapes 61A, 62A, 63A, 64A, and 65A on battery cell 22A, the outer fixing tapes 61B, 62B, 63B, 64B, and 65B on battery cell 22B, and the outer fixing tapes 61C, 62C, 63C, 64C, and 65C on battery cell 22C do not overlap in the stacking direction. Therefore, in the cell laminate 220 shown in Figure 5, the increase in the overall thickness of the cell laminate caused by the fixing tape can be suppressed. This reduces the thickness of the cell laminate, improves volumetric efficiency, and increases energy density.

[0028] • Third aspect Next, another embodiment (a third embodiment) of the cell laminate according to the present disclosure will be described with reference to the drawings.

[0029] Figure 6 is a schematic side view showing a cell laminate according to the third embodiment, and is a side view of the electrode body as seen from the side. Note that Figure 6 shows a side view of the inside of the laminate film.

[0030] First, let's describe one battery cell 24D in the cell stack 240 shown in Figure 6. The electrode body 4 in the battery cell 24D has terminals (tabs) 26 on each of its longitudinal sides. Three inner fixing tapes 41D to 43D are attached to the outer surface of the electrode body 4 so as to wrap around it. Each of the inner fixing tapes 41D to 43D is wrapped around the four sides of the electrode body 4 that do not have terminals 26. The electrode body 4, secured by three internal fixing tapes 41D to 43D, is covered and sealed inside a laminate film 28, which is an example of a laminate outer casing. Furthermore, three external fixing tapes 61D to 63D are placed around the electrode body 4 sealed in the laminate film 28, wrapped around the outer surface of the laminate film 28. All of the external fixing tapes 61D to 63D are wrapped around the four sides of the laminate film 28 where there are no terminals 26. In other words, the battery cell 24D is secured by inner fixing tapes 41D to 43D that are directly wrapped around the outer surface of the electrode body 4, and outer fixing tapes 61D to 63D that are wrapped around the outer surface of the laminate film 28.

[0031] Note that while the battery cells 24D, 24E, and 24F shown in Figure 6 are all fixed with three inner fixing tapes and three outer fixing tapes, the design is not limited to this configuration. The number of inner fixing tapes wrapped around a single electrode body 4 can be one or more, and the number of outer fixing tapes wrapped around the laminate film 28 can also be one or more.

[0032] The cell stack 240 according to the third embodiment has a structure in which three battery cells 24D, 24E, and 24F are stacked. Furthermore, the wrapping positions of the fixing tapes do not overlap in the stacking direction between all adjacent battery cells, that is, between adjacent battery cells 24D and 24E, and between adjacent battery cells 24E and 24F. Specifically, the wrapping positions of the inner fixing tapes 41D, 42D, 43D and outer fixing tapes 61D, 62D, 63D on battery cell 24D and the inner fixing tapes 41E, 42E, 43E and outer fixing tapes 61E, 62E, 63E on battery cell 24E adjacent to battery cell 24D do not overlap in the stacking direction. Furthermore, the wrapping positions of the inner fixing tapes 41E, 42E, 43E and outer fixing tapes 61E, 62E, 63E on battery cell 24E and the inner fixing tapes 41F, 42F, 43F and outer fixing tapes 61F, 62F, 63F on battery cell 24F adjacent to battery cell 24E do not overlap in the stacking direction. Furthermore, the wrapping positions of the fixing tapes do not overlap in the stacking direction for any of the battery cells, namely battery cell 24D, battery cell 24E, and battery cell 24F. Specifically, the wrapping positions of the inner fixing tapes 41D, 42D, 43D and outer fixing tapes 61D, 62D, 63D on battery cell 24D, the inner fixing tapes 41E, 42E, 43E and outer fixing tapes 61E, 62E, 63E on battery cell 24E, and the inner fixing tapes 41F, 42F, 43F and outer fixing tapes 61F, 62F, 63F on battery cell 24F do not overlap in the stacking direction. Therefore, in the cell laminate 240 shown in Figure 6, the increase in the overall thickness of the cell laminate caused by the fixing tape can be suppressed. This reduces the thickness of the cell laminate, improves volumetric efficiency, and increases energy density.

[0033] Furthermore, in the cell stack 240 shown in Figure 6, the winding positions of the inner fixing tapes 41D, 42D, and 43D do not overlap with the winding positions of the outer fixing tapes 61D, 62D, and 63D in one battery cell 24D. Similarly, in one battery cell 24E, the winding positions of the inner fixing tapes 41E, 42E, and 43E do not overlap with the winding positions of the outer fixing tapes 61E, 62E, and 63E. Moreover, in one battery cell 24F, the winding positions of the inner fixing tapes 41F, 42F, and 43F do not overlap with the winding positions of the outer fixing tapes 61F, 62F, and 63F. Therefore, in the cell stack 240 shown in Figure 6, the increase in the overall thickness of the cell stack caused by the winding position of the inner and outer fixing tapes in a single battery cell can be suppressed. This reduces the thickness of the cell stack, improves volumetric efficiency, and increases energy density.

[0034] · Modification Here, the cell stacks of the first embodiment shown in Figure 3, the cell stacks of the second embodiment shown in Figure 5, and the cell stacks of the third embodiment shown in Figure 6 show embodiments in which the wrapping positions of the fixing tape do not overlap in the stacking direction for all battery cells, but the invention is not limited to these embodiments. For example, the wrapping positions of the fixing tape may not overlap in the stacking direction for all adjacent battery cells, while the wrapping positions of the fixing tape may overlap in the stacking direction for some non-adjacent battery cells.

[0035] For example, the cell stack 222 shown in Figure 7 has a structure in which three battery cells 22L, 22M, and 22N are stacked. Furthermore, the wrapping positions of the fixing tape do not overlap in the stacking direction between all adjacent battery cells, that is, between adjacent battery cells 22L and 22M, and between adjacent battery cells 22M and 22N. Specifically, the wrapping positions of the outer fixing tapes 61L, 62L, 63L, 64L, and 65L on battery cell 22L and the outer fixing tapes 61M, 62M, 63M, 64M, and 65M on battery cell 22M adjacent to battery cell 22L do not overlap in the stacking direction. Furthermore, the wrapping positions of the outer fixing tapes 61M, 62M, 63M, 64M, and 65M on battery cell 22M and the outer fixing tapes 61N, 62N, 63N, 64N, and 65N on battery cell 22N adjacent to battery cell 22M do not overlap in the stacking direction. On the other hand, the wrapping positions of the outer fixing tapes 61L, 62L, 63L, 64L, and 65L on battery cell 22L and the outer fixing tapes 61N, 62N, 63N, 64N, and 65N on battery cell 22N that is not adjacent to battery cell 22L overlap in the stacking direction. As shown in Figure 7, by ensuring that the wrapping positions of the fixing tape do not overlap in the stacking direction for all adjacent battery cells, the increase in the overall thickness of the cell stack due to the fixing tape can be suppressed. This reduces the thickness of the cell stack, improves volumetric efficiency, and increases energy density.

[0036] Furthermore, while Figure 3 shows an example of a cell stack in the first embodiment, Figure 5 shows an example of a cell stack in the second embodiment, and Figure 6 shows an example of a cell stack in which three battery cells are stacked, the invention is not limited to these examples. For instance, the number of battery cells stacked in a cell stack may be two or more, ten or more battery cells may be stacked, or twenty or more battery cells may be stacked. In either case, the fixing tape is wrapped around at least one pair of adjacent battery cells so that the wrapping positions of the fixing tape do not overlap in the stacking direction. Preferably, the fixing tape is wrapped around all adjacent battery cells so that the wrapping positions of the fixing tape do not overlap in the stacking direction. Even more preferably, the fixing tape is wrapped around all battery cells so that the wrapping positions of the fixing tape do not overlap in the stacking direction.

[0037] Next, a battery module, a battery pack, and a vehicle having a cell stack according to the embodiment of this disclosure will be described with reference to the figures.

[0038] (Overall configuration of vehicle 100) Figure 8 is a schematic plan view showing the main parts of a vehicle 100 to which the battery pack 10 according to the embodiment is applied. As shown in Figure 8, the vehicle 100 is a battery electric vehicle (BEV) with the battery pack 10 mounted under the floor. In each figure, the arrows UP, FR, and LH indicate the upper side in the vertical direction of the vehicle, the front side in the longitudinal direction of the vehicle, and the left side in the width direction of the vehicle, respectively. When describing directions such as front, rear, left, right, up, and down, unless otherwise specified, they refer to the front and rear in the longitudinal direction of the vehicle, the left and right in the width direction of the vehicle, and the up and down in the vertical direction of the vehicle.

[0039] In this embodiment, the vehicle 100, as an example, has a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 positioned in front of the battery pack 10. The motor 108, gearbox 110, inverter 112, and charger 114 are positioned behind the battery pack 10.

[0040] The DC current output from the battery pack 10 is voltage-adjusted by the DC / DC converter 102 and then supplied to the electric compressor 104, PTC heater 106, inverter 112, etc. Power is also supplied to the motor 108 via the inverter 112, causing the rear wheels to rotate and the vehicle 100 to move.

[0041] A charging port 116 is provided on the right side of the rear of the vehicle 100. By connecting a charging plug from an external charging device (not shown) to the charging port 116, power can be stored in the battery pack 10 via the charger 114.

[0042] The arrangement and structure of the components constituting the vehicle 100 are not limited to the configuration described above. For example, it may be applied to a hybrid vehicle (HV) or a plug-in hybrid electric vehicle (PHEV) equipped with an engine. In this embodiment, the motor 108 is mounted at the rear of the vehicle and it is a rear-wheel drive vehicle, but it is not limited to this, and it may be a front-wheel drive vehicle with the motor 108 mounted at the front of the vehicle, or a pair of motors 108 may be mounted at the front and rear of the vehicle. Furthermore, it may be a vehicle equipped with in-wheel motors for each wheel.

[0043] Here, the battery pack 10 is composed of multiple battery modules 11. In this embodiment, as an example, 10 battery modules 11 are provided. Specifically, 5 battery modules 11 are arranged in the longitudinal direction of the vehicle on the right side of the vehicle 100, and 5 battery modules 11 are arranged in the longitudinal direction of the vehicle on the left side of the vehicle 100. Furthermore, each battery module 11 is electrically connected.

[0044] Figure 9 is a schematic perspective view of the battery module 11. As shown in Figure 9, the battery module 11 is formed in a roughly rectangular parallelepiped shape with the vehicle width direction as its longitudinal direction. The outer shell of the battery module 11 is made of aluminum alloy. For example, the outer shell of the battery module 11 is formed by joining aluminum die-cast parts to both ends of an aluminum alloy extruded material by laser welding or the like.

[0045] A pair of voltage terminals 12 and a connector 14 are provided at both ends of the battery module 11 in the vehicle width direction. A flexible printed circuit board 22, which will be described later, is connected to the connector 14. In addition, busbars (not shown) are welded to both ends of the battery module 11 in the vehicle width direction.

[0046] The length MW of the battery module 11 in the vehicle width direction is, for example, 350 mm to 600 mm, the length ML in the vehicle longitudinal direction is, for example, 150 mm to 250 mm, and the height MH in the vehicle vertical direction is, for example, 80 mm to 110 mm.

[0047] Figure 10 is a plan view of the battery module 11 with the top cover removed. As shown in Figure 10, multiple battery cells 20 are housed inside the battery module 11 in an arranged state. In this embodiment, as an example, 24 battery cells 20 are arranged in the front-rear direction of the vehicle and bonded to each other.

[0048] A flexible printed circuit board (FPC) 22 is placed on top of the battery cell 20. The flexible printed circuit board 22 is formed in a strip shape with the vehicle width direction as its longitudinal direction, and thermistors 24 are provided at both ends of the flexible printed circuit board 22. The thermistors 24 are not bonded to the battery cell 20, but are pressed toward the battery cell 20 by the upper cover of the battery module 11.

[0049] Furthermore, one or more cushioning materials (not shown) are housed inside the battery module 11. For example, the cushioning material is a thin, elastically deformable plate-like member, and is arranged between adjacent battery cells 20 with the arrangement direction of the battery cells 20 as the thickness direction. In this embodiment, as an example, cushioning material is arranged at both ends in the longitudinal direction and in the longitudinal center of the battery module 11.

[0050] Figure 11 is a schematic view of a battery cell 20 housed in a battery module 11, viewed from the thickness direction. As shown in Figure 11, the battery cell 20 is formed in a roughly rectangular plate shape, and an electrode body (not shown) is housed inside. The electrode body is composed of a positive electrode, a negative electrode, and a separator stacked together, and is sealed with a laminate film 28.

[0051] In this embodiment, as an example, the electrode housing is formed by folding and bonding an embossed sheet-like laminate film 28. While both a single-cup embossed structure with one embossed area and a double-cup embossed structure with two embossed areas can be employed, this embodiment uses a single-cup embossed structure with a fold depth of approximately 8mm to 10mm.

[0052] The upper ends of both longitudinal sides of the battery cell 20 are bent, and the corners form the outer shape. The upper end of the battery cell 20 is also bent.

[0053] Here, terminals (tabs) 26 are provided at both longitudinal ends of the battery cell 20. In this embodiment, as an example, the terminals 26 are provided at a position offset below the vertical center of the battery cell 20. The terminals 26 are joined to a busbar (not shown) by laser welding or the like.

[0054] The length CW1 of the battery cell 20 in the vehicle width direction is, for example, 530mm~600mm, 600mm~700mm, 700mm~800mm, 800~900mm, and 1000mm or more. The length CW2 of the area where the electrode body is housed is, for example, 500mm~520mm, 600mm~700mm, 700mm~800mm, 800~900mm, and 1000mm or more. The height CH of the battery cell 20 is, for example, 80mm~110mm and 110mm~140mm. The thickness of the battery cell 20 is 5.0mm~7.0mm, 7.0mm~9.0mm, and 9.0mm~11.0mm. The height TH of the terminal 26 is 40mm~50mm, 50mm~60mm, and 60mm~70mm. [Explanation of Symbols]

[0055] 4 Electrode bodies, 10 Battery packs, 11 Battery modules, 12 Voltage terminals, 14 Connectors, 20, 20A, 20B, 20C, 22, 22A, 22B, 22C, 22L, 22M, 22N, 24D, 24E, 24F Battery cells, 22 Flexible printed circuit boards, 24 Thermistors, 26 Terminals, 28 Laminate film, 41, 41A, 41B, 41C, 41D, 41E, 41F, 42, 42A, 42B, 42C, 42D, 42E, 42F, 43, 43A, 43B, 43C, 43D, 43E, 43F, 44, 44A, 44B, 44C, 45, 45A, 45B, 45C Internal fixing tape, 61, 61A, 61B, 61C, 61D, 61E, 61F, 61L, 61M, 61N, 62, 62A, 62B, 62C, 62D, 62E, 62F, 62L, 62M, 62N, 63, 63A, 63B, 63C, 63D, 63E, 63F, 63L, 63M, 63N, 64, 64A, 64B, 64C, 64L, 64M, 64N, 65, 65A, 65B, 65C, 65L, 65M, 65N External fixing tape, 100 Vehicle, 102 Converter, 104 Electric compressor, 106 Heater, 108 Motor, 110 Gearbox, 112 Inverter, 114 Charger, 116 Charging port, 200, 220, 222, 240 cell stack

Claims

1. Electrode body and A laminate outer casing that covers the electrode body and seals it inside, At least one of the fixing tapes, an inner fixing tape wrapped circumferentially around the outer surface of the electrode body inside the laminate outer casing, and an outer fixing tape wrapped circumferentially around the outer surface of the laminate outer casing, A cell stack in which multiple battery cells having are stacked, When the direction in which the multiple battery cells are stacked is defined as the stacking direction, A cell stack in which the fixing tape is wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the fixing tape do not overlap in the stacking direction.

2. The aforementioned fixing tape consists only of the inner fixing tape, The cell laminate according to claim 1, wherein the inner fixing tape is wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the inner fixing tape do not overlap in the stacking direction.

3. The aforementioned fixing tape consists only of the outer fixing tape, The cell laminate according to claim 1, wherein the outer fixing tape is wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the outer fixing tape do not overlap in the stacking direction.

4. The aforementioned fixing tape includes the inner fixing tape and the outer fixing tape, The cell laminate according to claim 1, wherein the inner fixing tape and the outer fixing tape are wrapped around at least one pair of adjacent battery cells such that the wrapping positions of the inner fixing tape and the outer fixing tape do not overlap in the stacking direction.

5. The cell laminate according to claim 4, wherein in one of the battery cells, the fixing tape is wrapped around the battery cell such that the wrapping position of the inner fixing tape and the wrapping position of the outer fixing tape do not overlap.

6. The cell laminate according to claim 1, wherein the fixing tape is wrapped around all adjacent battery cells such that the wrapping positions of the fixing tape do not overlap in the stacking direction.

7. The cell laminate according to claim 6, wherein the fixing tape is wrapped around all of the battery cells such that the wrapping positions of the fixing tape do not overlap in the stacking direction.

8. A battery module having a cell stack according to any one of claims 1 to 7.

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