阅读说明：本技术 具有薄板型的模块外罩的电池模块和包括该电池模块的电池组 (Battery module having thin plate type module cover and battery pack including the same ) 是由 池昊俊 金炅模 文祯晤 朴真用 陈喜俊 于 2020-03-19 设计创作，主要内容包括：根据本发明的电池模块是如下电池模块,该电池模块包括：多个电池单体；和模块外罩,该模块外罩形成用于容纳电池单体的内部空间,其中,模块外罩可以包括：基板,该基板形成模块外罩的底表面；盖板,该盖板一体地形成模块外罩的上表面和两侧；和紧固凸缘,该紧固凸缘从模块外罩的两侧上的上部区域沿着水平方向延伸。(A battery module according to the present invention is a battery module including: a plurality of battery cells; and a module housing forming an inner space for accommodating the battery cells, wherein the module housing may include: a substrate forming a bottom surface of the module housing; a cover plate integrally forming an upper surface and both sides of the module housing; and fastening flanges extending in a horizontal direction from upper regions on both sides of the module case.)

1. A battery module having a plurality of battery cells and a module cover forming an inner space for receiving the battery cells,

wherein the module housing includes:

a substrate forming a bottom surface of the module housing;

a cover plate integrally forming a top surface and both side surfaces of the module housing; and

a fastening flange configured to extend in a horizontal direction in a region above both side surfaces of the module housing.

2. The battery module according to claim 1, wherein the cap plate is formed in a thin plate type having a thickness of 0.1mm to 1 mm.

3. The battery module according to claim 1, wherein the cap plate comprises: a top portion forming the top surface of the module housing; and first and second side portions forming the both side surfaces of the module housing, and

an impact absorber is further attached to an outer surface of at least one of the first side portion and the second side portion.

4. The battery module according to claim 3, wherein the shock absorber is a plate spring attached to an outer surface of the first side portion and an outer surface of the second side portion, respectively, and

the plate spring has a center portion convexly curved, and top and bottom portions of the plate spring based on the center portion are welded to the outer surfaces of the first side portion and the second side portion.

5. The battery module according to claim 4, wherein the plate spring is formed integrally with the fastening flange, and

the fastening flange is provided to be bent at the top of the plate spring in a direction crossing the plate spring, and has at least one hole.

6. A battery pack, comprising:

at least one battery module according to any one of claims 1 to 5; and

a battery pack tray configured to provide a space in which the at least one battery module is mounted,

wherein the battery tray includes a plurality of rigid beams configured to support both sides of the battery module.

7. The battery pack of claim 6, wherein the battery module is placed between two of the rigid beams, and the fastening flange is coupled to a top surface of the rigid beams.

8. The battery pack of claim 7, further comprising:

a battery pack cover coupled to the battery pack tray and configured to cover an upper portion of the battery module.

9. The battery pack according to claim 8, wherein the battery pack cover, the fastening flange, and the rigid beam are integrally fastened to each other by a fastening member.

10. The battery pack of claim 8, further comprising:

a spacer attached to a bottom surface of the battery pack cover and configured to surface press the fastening flange.

11. The battery pack of claim 8, further comprising:

a cushion pad attached to a bottom surface of the battery pack cover and bonded to a top surface of the module enclosure.

12. The battery pack of claim 6, further comprising:

a heat sink disposed at a bottom surface of the at least one battery module.

Technical Field

The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module and a battery pack including the same for improving space utilization and ensuring mechanical rigidity.

This application claims priority to korean patent application No. 10-2019-0032422, filed in korea on 21/3/2019, the disclosure of which is incorporated herein by reference.

Background

Unlike a primary battery that cannot be charged, a secondary battery refers to a battery that can be charged and discharged, and the secondary battery is used not only as a power source for small high-tech electronic products such as a cellular phone, a PDA, or a notebook computer, but also as a power source for an Energy Storage System (ESS), an Electric Vehicle (EV), or a Hybrid Electric Vehicle (HEV).

The secondary batteries widely used at present include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and the like. The operating voltage of the unit secondary battery cell, i.e., the unit battery cell, is about 2.5V to 4.2V. Therefore, if a higher output voltage and a greater energy capacity are required, a plurality of battery cells are connected in series to construct a battery module, or two or more battery modules are connected in series or in parallel, and other components are added to construct a battery pack. For example, the battery module may refer to a device in which a plurality of secondary batteries are connected in series or in parallel, and the battery pack may refer to a device in which battery modules are connected in series or in parallel to increase capacity and output.

As shown in fig. 1, a battery module 1 includes a module case 2, the module case 2 receiving and enclosing battery cells therein and protecting the battery cells from external impacts. The module case 2 is made of a thick steel plate and serves to safely protect the battery cells from external impact.

The battery pack includes a battery tray 3 as a structure for providing a space in which the battery module can be mounted. The battery pack for an electric vehicle employs a plurality of cross members 4 provided across the inner space of the battery tray 3 to prevent deformation, such as warping, caused by impact during operation.

Conventional battery modules are placed between the cross members, for example, in a pattern as shown in fig. 2, and long bolts B are inserted into a total of four module/battery pack fastening parts at the front and rear corners, respectively, and fastened to the top surface of the battery pack tray 3. In this way, the battery module is fixed to the battery tray 3.

However, conventionally, when manufacturing a battery pack, in order to secure assembly tolerance and strength reliability, a certain gap is provided between the battery module 1 and the cross member on the battery pack tray, but the gap plays a negative factor in the space utilization of the battery pack tray. In particular, if the battery pack is assembled using battery modules having the rigid module housing 2, the welding rate or the energy share of the battery modules in the battery pack tray is further reduced due to the space occupied by the thickness of the module housing.

Therefore, it is necessary to find a technology for safely protecting the battery cells from external impacts while maximizing the space of the battery cells by reducing the size of the structure in the battery module or the battery pack.

Disclosure of Invention

Technical problem

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing a battery module and a battery pack having the following structures: this structure may maximize a space capable of accommodating the battery cells and safely protect the battery cells from mechanical shock and vibration.

These and other objects and advantages of the present disclosure will be understood from the following detailed description, and will become more apparent in light of the exemplary embodiments of the present disclosure. Also, it will be readily understood that the objects and advantages of the present disclosure may be realized by the means as set forth in the appended claims and combinations thereof.

Technical scheme

In one aspect of the present disclosure, there is provided a battery module having a plurality of battery cells and a module housing forming an inner space for receiving the battery cells, wherein the module housing includes: a substrate forming a bottom surface of the module housing; a cover plate integrally forming a top surface and both side surfaces of the module housing; and fastening flanges configured to extend in a horizontal direction in regions above both side surfaces of the module case.

The cover plate may be formed in a thin plate type having a thickness of 0.1mm to 1 mm.

The cover plate may include: a top portion forming a top surface of the module housing; and first and second side portions that form both side surfaces of the module housing, and the shock absorber may be further attached to an outer surface of at least one of the first and second side portions.

The shock absorber may be a plate spring attached to outer surfaces of the first side portion and the second side portion, respectively, and the plate spring may have a center portion convexly curved, and top and bottom portions of the plate spring based on the center portion may be welded to the outer surfaces of the first side portion and the second side portion.

The plate spring may be formed integrally with the fastening flange, and the fastening flange may be provided to be bent at a top portion of the plate spring in a direction crossing the plate spring, and have at least one hole.

In another aspect of the present disclosure, there is also provided a battery pack including: at least one of the above battery modules; and a battery tray configured to provide a space in which the at least one battery module is mounted, wherein the battery tray includes a plurality of rigid beams configured to support both side portions of the battery module.

The battery module may be placed between two of the rigid beams, and the fastening flange may be coupled to a top surface of the rigid beams.

The battery pack may further include a battery pack cover coupled to the battery pack tray and configured to cover an upper portion of the battery module.

The battery pack cover, the fastening flange, and the rigid beam may be integrally fastened to each other by a fastening member.

The battery pack may further include a spacer attached to a bottom surface of the pack cover and configured to surface-press the fastening flange.

The battery pack may further include a cushion pad attached to a bottom surface of the battery pack cover and bonded to a top surface of the module enclosure.

The battery pack may further include a heat sink disposed at a bottom surface of the at least one battery module.

Advantageous effects

According to the embodiments of the present disclosure, by forming the module housing in a thin plate type, it is possible to provide a battery module having a higher cell volume ratio and a light weight than a conventional battery module.

According to another embodiment of the present disclosure, it is possible to provide a battery pack configured such that battery modules having a thin plate-type module housing have mechanical rigidity and allow the battery modules to be fixed in a space-efficient manner.

Drawings

Fig. 1 is a perspective view schematically illustrating a module case of a conventional battery module.

Fig. 2 is a view schematically illustrating a conventional battery module assembled with a battery tray.

Fig. 3 is a perspective view schematically illustrating a module case of a battery module according to an embodiment of the present disclosure.

Fig. 4 is a perspective view illustrating a cover plate of the module case of fig. 3.

Fig. 5 is a partially enlarged view of fig. 4.

Fig. 6 is a view showing the shock absorber of fig. 4 as viewed in the direction a of fig. 4.

Fig. 7 is a perspective view schematically illustrating a battery pack according to an embodiment of the present disclosure.

Fig. 8 is a partially enlarged view of the battery pack of fig. 7.

Fig. 9 is a sectional view illustrating an assembly structure of a battery module and a battery pack tray according to an embodiment of the present disclosure.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before the description, it should be understood that the terms used in the specification and the appended claims should not be construed as limited to general and dictionary meanings, but interpreted based on the meanings and concepts corresponding to technical aspects of the present invention on the basis of the principle that the inventor is allowed to define terms appropriately for the best explanation. Accordingly, the description set forth herein is intended as a preferred example for purposes of illustration only and is not intended to limit the scope of the present disclosure, so it will be understood that other equivalents and modifications may be made thereto without departing from the scope of the present disclosure.

Fig. 3 is a perspective view schematically illustrating a module case of a battery module according to an embodiment of the present disclosure, and fig. 4 is a perspective view illustrating a cap plate of the module case of fig. 3.

The battery module 10 according to the embodiment of the present disclosure includes a plurality of battery cells (not shown) and a module cover 11 for receiving the plurality of battery cells in an inner space of the module cover 11.

The plurality of battery cells are lithium ion secondary batteries capable of charging and discharging, and may be pouch type secondary batteries having high energy density and ensuring easy stacking. Although not shown in the drawings for convenience, pouch-type secondary batteries may be stacked in one direction to overlap each other and be accommodated in the module case 11, and may be connected in series and/or in parallel through an ICB (interconnect board) according to a required output voltage or charge/discharge capacity.

The battery cell is not necessarily limited to the pouch type lithium ion secondary battery. For example, the battery cell may be a can-type lithium ion secondary battery, a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery, or the like.

Referring to fig. 3 and 4, the module case 11 has a rectangular tubular shape made of a thin plate, and includes a base plate 12 and a cover plate 13.

The base plate 12 is a portion forming the bottom surface of the module case 11, and is substantially in the shape of a plate having a flat surface. Also, the edge of the base plate 12 may be bent upward to be combined with the cover plate 13. As a material of the substrate 12, a metal such as aluminum or an aluminum alloy having excellent thermal conductivity can be used. A heat sink may be placed at the lower surface of the substrate 12 so that the battery module 10 is cooled in an indirect water cooling manner.

In this embodiment, the base plate 12 is made into a thin plate type having a thickness of 1mm or less to promote thermal conductivity and weight reduction of the module case 11. However, the thickness of the substrate 12 is not necessarily limited to a thin plate type. Since the base plate 12 is a part supporting the weight of the battery cell, the base plate 12 may be made using a heavy plate or thick plate having a thickness of 3mm or more in order to increase the rigidity thereof so that the stability of the bottom surface of the module housing 11 is ensured.

The cover plate 13 is a portion integrally forming the top surface and both side surfaces of the module housing 11, and may have a cross section of approximatelyThe lid shape of the shape, and is formed using a thin plate having a thickness of 0.1mm to 1 mm. Hereinafter, in the cover plate 13, a portion forming the top surface of the module housing 11 will be defined as a top 14, forming a modulePortions of the left and right surfaces of the outer cover 11 will be defined as first and second side portions 15 and 16, respectively.

The first side portion 15 and the second side portion 16 of the lid plate 13 are coupled to both edge portions of the base plate 12 by welding to provide a rectangular tube-shaped module enclosure 11. In the module case 11, for example, a pouch-type battery cell may be inserted in a state where a wide surface thereof is vertically erected.

As described above, the module case 11 according to the present disclosure is made of a thin plate having a thickness of 1mm or less, and thus has a disadvantage in that it is weak in mechanical rigidity as compared to the conventional module case 11 having the same size. However, since the module case 11 according to the present disclosure is reduced in thickness, it is relatively light, and also has a higher monomer volume ratio and lower manufacturing costs since its inner space is enlarged.

When the battery module 10 is mounted to the battery tray 20, the insufficient rigidity of the thin plate-type module cover 11 can be reinforced by the battery tray 20. This will be described in detail later.

The battery module 10 according to this embodiment may further include: a shock absorber 18, the shock absorber 18 serving as a buffer means for both side surfaces of the module case 11; and a fastening flange 17, the fastening flange 17 serving as a means for fixing the module housing 11 to the battery tray 20.

Impact absorbers 18 may be attached to the outer surfaces of the first side portion 15 and the second side portion 16, respectively, to cushion impacts applied to the corresponding portions. The shock absorber 18 may employ an elastic body such as memory foam, a rubber pad, or a spring, but in this embodiment, a leaf spring 18 of small volume and weight is applied.

In the plate spring 18, as shown in fig. 4 to 6, a center portion 18a is convexly curved, and a top portion 18b and a bottom portion 18c of the plate spring 18 based on the center portion 18a may be attached to an outer surface of the first side portion 15 or an outer surface of the second side portion 16 by welding. When an external impact is applied, the bent center portion 18a may be concavely deformed, so that the plate spring 18 functions to buffer the impact applied to the module case 11.

In addition, the plate spring 18 according to this embodiment is designed to have an area corresponding to the first and second side portions 15 and 16, a thickness of about 0.5T, and a gap G of about 1.2mm between the central portion 18a and the side surface of the module case 11, so that the increase in width of the battery module 10 due to the attachment of the plate spring 18 is not large.

The fastening flange 17 may be formed integrally with the plate spring 18. Referring again to fig. 4 to 6, the fastening flange 17 is provided integrally with the plate spring 18 to be bent at the top of the plate spring 18 in a direction crossing the plate spring 18, so that the fastening flange 17 extends in a horizontal direction in a region above both side surfaces of the module case 11. Also, at least one hole H is provided in the plate surface of the fastening flange 17 such that a bolt is inserted into the at least one hole H. In this embodiment, four fastening flanges 17 are provided at regular intervals along the length direction of the plate spring 18, but the number of fastening flanges 17 may be increased or decreased. For reference, the position of the fastening flange 17 may correspond to the height of a rigid beam 21 provided to the battery tray 20 on which the battery module 10 is placed.

As an alternative to this embodiment, the fastening flange 17 may be formed integrally with the cover plate 13, for reference. In this case, however, the manufacturing process may become more complicated since the structure of the fastening flange 17 is added to the cover plate 13. Therefore, in this embodiment, the structure of the lid plate 13 is simplified to a thin plate form, and the fastening flange 17 and the plate spring 18 are integrally manufactured and attached to the lid plate 13. In addition, according to this method, the relative position of the fastening flange 17, that is, the height thereof, can be easily set by adjusting the size and attachment position of the plate spring 18 with respect to the side surface of the cover plate 13.

Fig. 7 is a perspective view schematically illustrating a battery pack according to an embodiment of the present disclosure, fig. 8 is a partially enlarged view of the battery pack of fig. 7, and fig. 9 is a sectional view illustrating an assembled structure of a battery module 10 and a battery tray 20 according to an embodiment of the present disclosure.

Referring to fig. 7 to 9, a battery pack 100 according to the present disclosure may include at least one of the above-described battery module 10, a battery pack tray 20, and a battery pack cover 30.

The battery tray 20 is a member for providing a space in which the battery modules 10 are mounted, and includes a plurality of rigid beams 21 forming walls.

The rigid beams 21 serve to maintain the rigidity of the battery tray 20 and to support both side portions of the battery module 10 to reinforce the insufficiency of rigidity of the battery module 10.

As shown in fig. 7 and 8, the battery tray 20 according to this embodiment is configured such that two battery modules 10 can be mounted to the battery tray 20. However, the battery tray 20 may also be configured such that one battery module 10 or three or more battery modules 10 may be mounted to the battery tray 20. That is, the size of the battery tray 20 and the number of the rigid beams 21 may be changed as necessary according to the number of the battery modules 10.

Specifically, the battery modules 10 are respectively placed between two rigid beams 21 of the battery pack tray 20, with the fastening flanges 17 being bolted to the top surfaces of the rigid beams 21, so that the fastening flanges 17 can be fixed.

In addition, the upper part of the battery module 10 may be covered and protected by the pack cover 30. As the edge portion of the battery pack cover 30 is bolted to the top surface of the rigid beam 21 together with the fastening flange 17, the battery pack cover 30 can be fixedly coupled to the battery pack tray 20.

Also, as shown in fig. 8 and 9, the battery pack 100 according to the embodiment further includes: a spacer 40, the spacer 40 being interposed between the fastening flange 17 and the edge portion of the battery pack cover 30; and a cushion 50, the cushion 50 being interposed between the battery pack cover 30 and the top surface of the module housing 11.

The spacer 40 is a member for protecting the fastening flange 17 from being damaged at the time of bolting and absorbing assembly tolerance caused by a height difference between the battery pack cover 30 and the fastening flange 17. The spacer 40 is provided in the form of a rubber band having a predetermined thickness, and may be pre-attached along both side edge lines at the bottom surface of the battery pack cover 30.

For example, the fastening flange 17 having a thin thickness of 0.5T may be easily damaged at the time of bolting, and may have a weak fixing force because it does not have a good contact with the battery pack cover 30 and the rigid beam 21. However, if the spacer 40 is used, since the spacer 40 disperses the axial force of the bolt and fixes the fastening flange 17 with the surface pressure, the above problem can be easily solved.

The buffer pad 50 is provided in the form of a pad having an area corresponding to the top surface of the module housing 11, and may be pre-attached to the central region of the bottom surface of the battery pack cover 30. An adhesive tape, which may be attached to the top surface of the battery module 10, may be further provided at the bottom surface of the buffer pad 50 such that the position of the battery pack cover 30 is not displaced when the battery pack cover 30 is placed on the battery module 10.

The buffer pads 50 are interposed between the pack cover 30 and the top surface of the battery module 10 to protect the battery module 10 from an impact applied from above while restraining the battery module 10 in the up, down, left, and right directions.

In the unit cell module 10, a total of eight fastening flanges 17 located at both side surfaces of the module housing 11 are bolted to the rigid beams 21, but when an impact is applied thereto, the fastening flanges 17 made of thin plates may be easily deformed. Therefore, in this embodiment, the battery pack cover 30 to which the cushion pad 50 is attached is disposed to press the upper surface of the module housing 11, and the cushion pad 50 is adhered to the top surface of the module housing 11, thereby preventing the battery module 10 from moving in the up, down, left, right, front, and rear directions, and thus compensating for the fixing force of the fastening flange 17.

Meanwhile, the heat sink 60 may be further interposed between the top surface of the battery tray 20 and the bottom surface of the battery module 10. The heat sink 60 is a component that: the battery module 10 is indirectly cooled by passing a coolant through the internal flow path, thereby absorbing heat from the battery module 10 by means of thermal contact.

The coolant flowing in the flow path is not particularly limited as long as it is a fluid that easily flows in the flow path and has excellent cooling performance. For example, the coolant may be water having high latent heat to maximize cooling efficiency. However, without being limited thereto, the coolant may also be antifreeze, gas coolant, air, or the like, as long as it forms a flow.

The heat sink 60 may be made of aluminum or an aluminum alloy having high thermal conductivity, but is not limited thereto. For example, the heat spreader 60 may be made of copper, gold, or silver. Ceramic materials such as aluminum nitride and silicon carbide may be used as the heat spreader 60 in addition to metals.

As described above, in the battery module 10 according to the present disclosure, the module housing 11 is made of a thin plate having a thickness of 1mm or less, so that the space for the battery cells is maximized and the weight of the module housing 11 is minimized. The weak rigidity of the battery module 10 may be enhanced by being attached to the battery tray 20. Hereinafter, this will be described in detail.

Referring to fig. 9, since the upper part of the battery module 10 is protected from external impact due to the battery pack cover 30 to which the buffer pads 50 are attached, and the other parts of the battery module 10 are restrained in the battery pack tray 20 of a rigid structure, it is possible to protect the battery module 10 from external impact.

In particular, since the rigid beam 21 of the battery tray 20 serves as a protection wall, the first and second side portions 15 and 16 of the cap plate 13 corresponding to both side surfaces of the battery module 10 can be protected primarily, and can be protected secondarily since the plate spring 18 absorbs an impact. In addition, the plate spring 18 may help tightly insert and fix the module housing 11 between the rigid beams 21 when the battery module 10 is mounted to the battery pack tray.

Meanwhile, the battery pack according to the present disclosure as described above may further include various means for controlling the charging and discharging of the battery modules, such as a BMS, a current sensor, and a fuse. The battery pack may be applied not only to vehicles such as electric vehicles or hybrid electric vehicles, but also to other IT products.

The present disclosure has been described in detail. It should be understood, however, that the detailed description and the specific examples, while indicating preferred embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the scope of the disclosure will become apparent to those skilled in the art from this detailed description.

Meanwhile, even though terms expressing directions such as "upper", "lower", "left", and "right" are used in the specification, they are merely for convenience of description, and can be expressed differently depending on the position of an observer or an object, as is apparent to those skilled in the art.