Battery module

Abstract

The invention relates to a battery module. This battery module is provided with: a battery cell formed by sealing an electrode body with a laminated film; and a housing capable of accommodating a battery cell group in which a plurality of the battery cells are arranged, and a lubricating member provided between the battery cell group and the housing.

Description

Technical Field

[0001] The present disclosure relates to a battery module. Background Art

[0002] The battery module in which the electrode assembly is housed in the outer casing is disclosed in the specification of U.S. Patent Application Publication No. 2018 / 287184. In addition, the thermal expansion of the electrode assembly is suppressed by surrounding the outer side of the electrode assembly with a heat shrinkable protective layer.

[0003] In order to improve the volume efficiency of the battery, it is preferred that the battery cells be housed in the battery module housing without gaps. However, if the volume of the housing is not sufficient for the volume of a battery cell group formed by arranging a plurality of battery cells, it is difficult to insert the battery cell group into the housing. Summary of the invention

[0004] The present disclosure takes the above-mentioned facts into consideration, and an object of the present disclosure is to obtain a battery module capable of housing more battery cells in a casing.

[0005] A battery module according to a first aspect includes: a battery cell formed by sealing an electrode body with a laminate film; and a case capable of housing a battery cell group in which a plurality of the battery cells are arranged, wherein a lubricant is provided between the battery cell group and the case.

[0006] In the battery module of the first embodiment, the battery cell is formed by sealing the electrode body with a laminate film, and the outer shell can accommodate a battery cell group formed by arranging a plurality of battery cells. In addition, a lubricant is provided between the battery cell group and the outer shell. Therefore, the friction resistance when the battery cell group is inserted into the outer shell can be reduced by the lubricant.

[0007] A battery module according to a second aspect is the battery module according to the first aspect, wherein the lubricant is formed to include a material that volatilizes under a specific environment.

[0008] In the battery module of the second aspect, after the battery cell group is inserted into the casing, the lubricant is volatilized and the battery cell group can be prevented from falling out of the casing.

[0009] In the battery module according to claim 3 , according to claim 1 , the lubricant is formed to include a material that increases the resistance of the battery cell to coming out of the casing under a specific environment.

[0010] In the battery module of the third aspect, by placing the battery cell group in a specific environment after being inserted into the outer casing, the resistance of the battery cells against the outer casing to coming out increases, thereby preventing the battery cell group from coming out of the outer casing.

[0011] A battery module according to a fourth aspect is characterized in that according to the third aspect, the lubricating member is solid and is formed to include a material whose friction coefficient increases under a specific environment.

[0012] In the battery module according to the fourth aspect, the friction coefficient of the lubricant increases under a specific environment, thereby preventing the battery cell group from falling off from the casing.

[0013] A battery module according to a fifth aspect is the battery module according to the third aspect, wherein the lubricating member is formed to include a material whose volume increases under a specific environment.

[0014] In the battery module according to the fifth aspect, the volume of the lubricant increases under specific circumstances, thereby preventing the battery cell group from falling off the casing.

[0015] A battery module according to a sixth aspect is according to any one of the second to fifth aspects, wherein the specific environment is a reduced pressure environment that is reduced pressure compared to atmospheric pressure.

[0016] In the battery module of the sixth aspect, the battery cell group can be prevented from falling out of the outer casing simply by reducing the pressure after the battery cell group is housed in the outer casing.

[0017] A battery module according to a seventh aspect is according to any one of the second to fifth aspects, wherein the specific environment is a high temperature environment having a temperature equal to or higher than a predetermined temperature.

[0018] In the battery module of the seventh aspect, the battery cell group can be prevented from falling out of the outer casing simply by placing the battery cell group in a high temperature environment after being housed in the outer casing.

[0019] The battery module of claim 8 is based on claim 1, wherein the battery cell group includes a buffer plate provided outside the outermost battery cell in the arrangement direction of the plurality of arranged battery cells, and a lubricant is provided between the buffer plate and the casing.

[0020] In the battery module according to the eighth aspect, since both ends of the battery cell group serve as buffer plates, the surface pressure acting on the battery cells can be adjusted.

[0021] As described above, according to the battery module according to the present disclosure, more battery cells can be housed in the casing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Typical embodiments of the present disclosure will be described in detail based on the following drawings.

[0023] Figure 1 It is a schematic plan view showing a main part of a vehicle to which the battery pack according to the first embodiment is applied.

[0024] Figure 2 This is a schematic perspective view of a battery module.

[0025] Figure 3 It is a top view of the battery module with the upper cover removed.

[0026] Figure 4 This is a schematic diagram of a battery cell housed in a battery module as viewed in the thickness direction.

[0027] Figure 5 This is a plan cross-sectional view schematically showing a state where a battery cell is inserted into a casing in the first embodiment.

[0028] Figure 6 This is a plan cross-sectional view schematically showing a state where a battery cell is inserted into a casing in the second embodiment.

[0029] Figure 7 This is a plan cross-sectional view schematically showing a state where a battery cell is inserted into a casing in the third embodiment. DETAILED DESCRIPTION

[0030] <First Embodiment>

[0031] The battery module 11 according to the first embodiment will be described with reference to the drawings.

[0032] (Overall Structure of Vehicle 100)

[0033] Figure 1 1 is a schematic plan view showing the main parts of a vehicle 100 to which the battery pack 10 according to the present embodiment is applied. Figure 1 As shown, the vehicle 100 is an electric vehicle (BEV) equipped with a battery pack 10 under the floor. In addition, the arrows UP, FR, and LH in each figure respectively indicate the upper side in the vehicle vertical direction, the front side in the vehicle front-back direction, and the left side in the vehicle width direction. When the front-back, left-right, up-down and down directions are used for explanation, unless otherwise specified, they indicate the front-back in the vehicle front-back direction, the left-right in the vehicle width direction, and the up-down in the vehicle vertical direction.

[0034] The vehicle 100 of the present embodiment is provided with a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 as an example on the vehicle front side relative to the battery pack 10. In addition, a motor 108, a gear box 110, an inverter 112, and a charger 114 are provided on the vehicle rear side relative to the battery pack 10.

[0035] The DC current output from battery pack 10 is regulated in voltage by DC / DC converter 102 and then supplied to electric compressor 104, PTC heater 106, inverter 112, etc. In addition, by supplying electric power to motor 108 via inverter 112, the rear wheels rotate and vehicle 100 travels.

[0036] A charging port 116 is provided on the right side of the rear portion of the vehicle 100 . By connecting a charging plug of an external charging device (not shown) to the charging port 116 , electric power can be stored in the battery pack 10 via the on-vehicle charger 114 .

[0037] In addition, the configuration and structure of each component constituting the vehicle 100 are not limited to the above-mentioned configuration. For example, it can also be applied to a hybrid vehicle (HV: Hybrid Vehicle) or a plug-in hybrid vehicle (PHEV: Plug-in Hybrid Electric Vehicle) equipped with an engine. In addition, in the present embodiment, the motor 108 is mounted on the rear of the vehicle and is a rear-wheel drive vehicle, but it is not limited to this. It can also be a front-wheel drive vehicle with the motor 108 mounted on the front of the vehicle, and a pair of motors 108 can be mounted on the front and rear of the vehicle. Moreover, it can also be a vehicle with a hub motor on each wheel.

[0038] Here, the battery pack 10 is configured to include a plurality of battery modules 11. In the present embodiment, as an example, 10 battery modules 11 are provided. Specifically, five battery modules 11 are arranged in the vehicle front-rear direction on the right side of the vehicle 100, and five battery modules 11 are arranged in the vehicle front-rear direction on the left side of the vehicle 100. In addition, each battery module 11 is electrically connected.

[0039] Figure 2 1 is a schematic three-dimensional diagram of the battery module 11. Figure 2 As shown, the battery module 11 is formed into a substantially rectangular parallelepiped shape with the vehicle width direction as the length direction. In addition, the housing 13 of the battery module 11 is formed of an aluminum alloy. For example, the housing 13 of the battery module 11 is formed by joining aluminum die castings at both ends of an aluminum alloy extrusion by laser welding or the like.

[0040] 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 21 described later is connected to the connector 14. Bus bars (not shown) are welded to both ends of the battery module 11 in the vehicle width direction.

[0041] The battery module 11 has a length MW in the vehicle width direction of, for example, 350 mm to 600 mm, a length ML in the vehicle front-rear direction of, for example, 150 mm to 250 mm, and a height MH in the vehicle vertical direction of, for example, 80 mm to 110 mm.

[0042] Figure 3 FIG. 1 is a top view of the battery module 11 with the upper cover removed. Figure 3 As shown, a plurality of battery cells 20 are housed in an aligned state inside the battery module 11. In the present embodiment, as an example, 24 battery cells 20 are aligned in the vehicle front-rear direction and bonded to each other.

[0043] A flexible printed circuit (FPC) 21 is disposed on the battery cell 20. The flexible printed circuit 21 is formed in a strip shape with the vehicle width direction as the longitudinal direction, and thermistors 23 are provided at both ends of the flexible printed circuit 21. The thermistor 23 is not bonded to the battery cell 20 and is pressed toward the battery cell 20 by the upper cover of the battery module 11.

[0044] In addition, one or more buffer plates (not shown) are accommodated inside the battery module 11. For example, the buffer plate is a thin plate-shaped member that can be elastically deformed, 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, buffer members are respectively arranged at both ends in the longitudinal direction and the central part in the longitudinal direction of the battery module 11.

[0045] Figure 4 2 is a schematic diagram of a battery cell 20 housed in a battery module 11 when viewed from the thickness direction. Figure 4 As shown, the battery cell 20 is formed in a substantially rectangular plate shape, and houses a long electrode body 19 inside. The electrode body 19 is formed by stacking a positive electrode, a negative electrode, and a separator, and is sealed by a laminate film 22 .

[0046] In this embodiment, as an example, the accommodating portion of the electrode body 19 is formed by folding and sticking together the sheet-like laminate film 22 after embossing. In addition, both a single cup embossing structure with embossing at one location and a double cup embossing structure with embossing at two locations can be adopted, but in this embodiment, a single cup embossing structure with a drawing depth of about 8 mm to 10 mm is used.

[0047] The upper end of the battery cell 20 is bent at both ends in the longitudinal direction, and the corners become the outer shape. In addition, the upper end of the battery cell 20 is bent, and a fixing band 24 is wound around the upper end of the battery cell 20 along the longitudinal direction.

[0048] Here, terminals (tabs) 26 are provided at both ends in the longitudinal direction of the battery cell 20. In the present embodiment, as an example, the terminals 26 are provided at positions offset downward from the vertical center of the battery cell 20. The terminals 26 are joined to a bus bar (not shown) by laser welding or the like.

[0049] The length CW1 of the battery cell 20 in the vehicle width direction is, for example, 530 mm to 600 mm, the length CW2 of the region containing the electrode body 19 is, for example, 500 mm to 520 mm, and the height CH of the battery cell 20 is, for example, 80 mm to 110 mm. Therefore, the battery cell 20 is formed in an elongated shape, and the directions of the lengths CW1 and CW2 are the longitudinal directions.

[0050] In addition, the thickness of the battery cell 20 is 7.0 mm to 9.0 mm, and the height TH of the terminal 26 is 40 mm to 50 mm.

[0051] Figure 5 1 is a top cross-sectional view schematically showing a state in which a battery cell group 25 is inserted into the housing 13 of the battery module 11 in this embodiment. In addition, for ease of explanation, 24 battery cells 20 arranged in the vehicle front-rear direction and bonded to each other are depicted as one battery cell group 25.

[0052] like Figure 5 As shown, a lubricant 50 is provided between the battery cell group 25 and the housing 13. In the present embodiment, as an example, the lubricant 50 is configured to contain lubricating oil that evaporates under a reduced pressure environment. In other words, the lubricant 50 is formed to contain a material that increases the resistance of the battery cell group 25 to the housing 13 from being pulled out under a specific environment. In addition, the "lubricant" mentioned here is a concept that widely includes a member that can reduce the friction between the battery cell group 25 and the housing 13, and is not limited to a liquid.

[0053] In the present embodiment, as an example, buffer plates are provided at both ends of the battery cell group 25 in the arrangement direction, and the lubricating material 50 is located between the buffer plates and the housing 13 .

[0054] For example, when manufacturing the battery module 11, first, the lubricant 50 is supplied to the inside of the housing 13. Then, with the lubricant 50 applied to the inner wall of the housing 13, the battery cell group 25 is inserted into the housing 13. At this time, the lubricant 50 is located between the buffer plate of the battery cell group 25 and the housing 13, so that the friction during insertion is reduced.

[0055] After the battery cell group 25 is inserted into the housing 13 and before the housing 13 is covered, the lubricant 50 is volatilized by reducing the pressure, and the battery cell group 25 and the housing 13 are fixed by friction.

[0056] (effect)

[0057] Next, the operation of the battery module 11 according to the present embodiment will be described.

[0058] In the battery module 11 according to the present embodiment, the battery cell 20 is formed by sealing the electrode body 19 with the laminate film 22, and the housing 13 can accommodate a battery cell group 25 in which a plurality of battery cells 20 are arranged. In addition, a lubricant 50 is provided between the battery cell group 25 and the housing 13. Therefore, the friction resistance when the battery cell group 25 is inserted into the housing 13 can be reduced by the lubricant 50.

[0059] In addition, in the present embodiment, the lubricant 50 is volatilized in a specific environment after the battery cell group 25 is inserted into the housing 13, and it is possible to suppress the battery cell group 25 from falling off from the housing 13. In particular, by using the lubricant 50 that volatilizes in a reduced pressure environment as a specific environment as in the present embodiment, it is possible to suppress the battery cell group 25 from falling off from the housing 13 simply by reducing the pressure after the battery cell group 25 is accommodated in the housing 13.

[0060] That is, by placing the battery cell group 25 in a reduced pressure environment after inserting it into the outer case 13, the resistance of the battery cells 20 against the outer case 13 increases and the battery cell group 25 can be prevented from falling out of the outer case 13. As a result, more battery cells 20 can be accommodated in the outer case 13.

[0061] Furthermore, in the present embodiment, since both ends of the battery cell group 25 serve as buffer plates, the surface pressure acting on the battery cells 20 can be adjusted.

[0062] <Second Embodiment>

[0063] Next, regarding the battery module 60 according to the second embodiment, refer to Figure 6 In addition, about the same structure as 1st Embodiment, the same code|symbol is attached|subjected, and description is abbreviate|omitted suitably.

[0064] Figure 6 1 is a top cross-sectional view schematically showing a state where the battery cell group 25 is inserted into the housing 13. Figure 6 As shown, in this embodiment, a plate-shaped lubricant 52 is provided between the battery cell group 25 and the housing 13 .

[0065] The lubricating material 52 of this embodiment is different from the first embodiment in that it is solid. The lubricating material 52 is formed in a plate shape, and both surfaces have a friction coefficient lower than that of the battery cell group 25 and the housing 13. That is, the surface of the lubricating material 52 has a smaller surface roughness than that of the battery cell group 25 and the housing 13.

[0066] In addition, the lubricating member 52 of the present embodiment is formed to include a material that does not volatilize in a reduced pressure environment and increases in volume in a high temperature environment to increase the removal resistance of the battery cell group 25. In other words, the lubricating member 52 is formed to include a material whose friction coefficient increases in a specific environment. Moreover, the lubricating member 52 is preferably formed of a material that is not easily thermally contracted even when cooled to room temperature.

[0067] (effect)

[0068] Next, the operation of the battery module 60 according to the present embodiment will be described.

[0069] In the battery module 60 according to this embodiment, when the battery cell group 25 is placed in a high temperature environment after being housed in the housing 13, the volume of the lubricant 52 increases, thereby preventing the battery cell group 25 from falling off the housing 13. Other effects are the same as those of the first embodiment.

[0070] <Third Embodiment>

[0071] Next, regarding the battery module 70 according to the second embodiment, refer to Figure 7 In addition, about the same structure as 1st Embodiment, the same code|symbol is attached|subjected, and description is abbreviate|omitted suitably.

[0072] Figure 7 1 is a top cross-sectional view schematically showing a state where the battery cell group 25 is inserted into the housing 13. Figure 7 As shown, in this embodiment, a lubricating material 50 similar to that of the first embodiment is provided between the battery cell group 25 and the casing 13 .

[0073] In addition, locking claws 13A are provided on the inner wall of the opening portion in the outer shell 13 to protrude in directions opposite to each other. Here, the locking claws 13A have inclined surfaces that are inclined in such a manner that the amount of protrusion increases as the amount of protrusion increases from the opening of the outer shell 13 to the inner side. Therefore, when the battery cell group 25 is inserted into the outer shell 13, since the battery cell group 25 is inserted along the inclined surface of the locking claws 13A, the resistance acting from the locking claws 13A to the battery cell group 25 is not large. On the other hand, when the battery cell group 25 moves from the inserted state to the direction of removal, the resistance to removal of the battery cell group 25 is increased by the relatively large friction force acting on the battery cell group 25 from the locking claws 13A.

[0074] (effect)

[0075] Next, the operation of the battery module 70 according to the present embodiment will be described.

[0076] In the battery module 70 according to the present embodiment, the lubricant 50 can be used to improve the insertability of the battery cell group 25 and to suppress the battery cell group 25 from coming out of the casing 13 .

[0077] Furthermore, if the gap between the housing 13 and the battery cell group 25 is sealed by the locking claws 13A, it is possible to suppress the lubricant 50 from leaking out of the housing 13. That is, it is not necessary to volatilize the lubricant 50. The other effects are the same as those of the first embodiment.

[0078] The battery modules 11, 60, and 70 involved in the embodiments are described above, but are not limited thereto and can be implemented in various ways without departing from the scope of the present disclosure. For example, as a lubricant, a material that increases the friction coefficient by increasing the viscosity under a specific environment can also be used. In addition, when the lubricant is a solid such as a buffer plate, a material that increases the friction coefficient by increasing the surface roughness under a specific environment can also be used.

[0079] Alternatively, a lubricant containing a material that increases the resistance to the battery cell coming out when a predetermined time or longer has passed under a specific environment may be used.

[0080] The following supplementary notes are disclosed with respect to the above-mentioned embodiment.

[0081] (Note 1)

[0082] A battery module comprising:

[0083] A battery cell formed by sealing an electrode body with a laminate film; and

[0084] The housing can accommodate a battery cell group formed by arranging a plurality of battery cells.

[0085] A lubricating member is provided between the battery cell group and the housing.

[0086] (Note 2)

[0087] According to the battery module described in Supplementary Note 1,

[0088] The lubricating member is formed to include a material that volatilizes under a specific environment.

[0089] (Note 3)

[0090] According to the battery module described in Supplementary Note 1,

[0091] The lubricating member is formed to include a material that increases the resistance of the battery cell to coming out of the housing under a specific environment.

[0092] (Note 4)

[0093] According to the battery module described in Supplementary Note 3,

[0094] The lubricating member is a solid formed to contain a material that increases the friction coefficient under certain circumstances.

[0095] (Note 5)

[0096] According to the battery module described in Supplementary Note 3,

[0097] The lubricating member is formed to include a material that increases in volume under certain circumstances.

[0098] (Note 6)

[0099] The battery module according to any one of Supplementary Notes 2 to 5,

[0100] The specific environment is a reduced pressure environment that is reduced in pressure compared to atmospheric pressure.

[0101] (Note 7)

[0102] The battery module according to any one of Supplementary Notes 2 to 5,

[0103] The specific environment is a high temperature environment with a temperature higher than a predetermined temperature.

[0104] (Note 8)

[0105] The battery module according to any one of Supplementary Notes 1 to 7,

[0106] The battery cell group includes a buffer plate provided outside the outermost battery cell in the arrangement direction among the plurality of arranged battery cells.

[0107] A lubricating member is provided between the buffer plate and the housing.

Claims

1. A battery module comprising: A battery cell formed by sealing an electrode body with a laminate film; and The housing can accommodate a battery cell group formed by arranging a plurality of battery cells. A lubricating member is provided between the battery cell group and the housing.

2. The battery module according to claim 1, The lubricating member is formed to include a material that volatilizes under a specific environment.

3. The battery module according to claim 1, The lubricating member is formed to include a material that increases the resistance of the battery cell to coming out of the housing under a specific environment.

4. The battery module according to claim 3, The lubricating member is a solid formed to contain a material that increases the friction coefficient under certain circumstances.

5. The battery module according to claim 3, The lubricating member is formed to include a material that increases in volume under certain circumstances.

6. The battery module according to any one of claims 2 to 5, The specific environment is a reduced pressure environment that is lower than the atmospheric pressure.

7. The battery module according to any one of claims 2 to 5, The specific environment is a high temperature environment with a temperature higher than a predetermined temperature.

8. The battery module according to claim 1, The battery cell group includes a buffer plate provided outside the outermost battery cell in the arrangement direction among the plurality of arranged battery cells. A lubricating member is provided between the buffer plate and the housing.

9. The battery module according to claim 1, Locking claws are provided on the inner wall of the opening portion of the housing in directions facing each other.

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