CN110168768B

CN110168768B - Battery module and vehicle including the same

Info

Publication number: CN110168768B
Application number: CN201780082495.9A
Authority: CN
Inventors: G.波沙尔尼格; G.扎夫卡; G.斯坦纳
Original assignee: Samsung SDI Co Ltd
Current assignee: Samsung SDI Co Ltd
Priority date: 2017-01-06
Filing date: 2017-12-13
Publication date: 2022-04-26
Anticipated expiration: 2037-12-13
Also published as: CN110168768A; WO2018128294A1

Abstract

Disclosed are a battery module and a vehicle including the same. A battery module according to an exemplary embodiment of the present invention includes: a case including a plurality of battery cells, a base plate, a case frame, and a cover plate; and gaskets interposed between the case frame and the base plate and between the case frame and the cover plate, respectively, wherein an upper flange of the case frame facing the cover plate and a lower flange of the case frame facing the base plate have a stepped shape including a recess opened to an inner side of the case frame, and the gaskets are disposed in the recess.

Description

Battery module and vehicle including the same

Technical Field

The present invention relates to a battery module and a vehicle including the same, and more particularly, to a battery module in which a gasket (gasket) of a battery module case has a particular design, and a vehicle including the same.

Background

Rechargeable batteries differ from primary batteries in that charging and discharging can be repeated, and primary batteries provide only an irreversible transition from chemical energy to electrical energy.

Low-capacity rechargeable batteries are used as power sources for small electronic devices such as cellular phones, laptop computers, and camcorders, and high-capacity rechargeable batteries are used as power sources for vehicles.

The rechargeable battery may include: an electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode; a case for accommodating the electrode assembly therein; and an electrode terminal electrically connected to the electrode assembly.

An electrolyte solution is injected into the case to enable the battery to be charged and discharged through electrochemical reactions of the positive electrode, the negative electrode, and the electrolyte solution. For example, the shape of the case (which may be cylindrical or rectangular) may vary depending on the use of the battery.

Rechargeable batteries are used in the form of battery modules including a plurality of unit battery cells connected in series or parallel, thereby providing high energy density for running, for example, a hybrid vehicle.

That is, the battery module may interconnect a plurality of unit battery cells according to an amount of power required to implement a high-power rechargeable battery, such as for an electric vehicle. A large-sized battery system used in an electric vehicle may include 3 to 1000 battery cells. Such battery cells may be provided as a plurality of battery modules, 10 to 20 battery cells being included in a general case in each battery module.

The battery module may be configured in a block type or a module type. In the case of the block type, each cell may be coupled to a common current collector and a common cell management system, and may have a housing.

In the case of the module type, a plurality of battery cells are connected to constitute sub-modules, and a plurality of sub-modules are connected to constitute one of the modules. The battery management functions may be implemented at least in part at the module or sub-module level to improve compatibility.

One or more battery modules may be mechanically and electrically integrated, have a thermal management system installed, and be connected to one or more power consuming devices to form a battery system.

The battery system may have three primary sealing regions, such as a housing gasket, a gasket for an electronic device such as a connector, and a gasket for a cooling system. The housing gasket protects the interior space of the housing from liquids or dust and protects its environment from high voltages during the entire cycle life of the battery system.

When applied to a vehicle, the battery should be able to withstand a pressure of about 10000Pa for a minimum of 30 minutes, prevent dust inflow, and the like. In addition, the housing gasket should have good durability against oil contamination or contact of electrolyte solution leaking from the battery cell.

On the other hand, the housing gasket must be able to be opened and closed, so that simple defects such as loose coupling of the cooling pipes can be corrected. In addition, for the design of the housing gasket, the material and surface structure of the housing need to be considered.

In a continuous production process such as mass production, it is necessary to optimize the manufacturing process of each housing gasket. For example, the housing may include auxiliary constituent elements for accelerating the fastening process.

The case of the battery may include three constituent elements, i.e., a base plate, a case frame, and a cover plate. The foam gasket may be provided in a groove or a plane between the above-mentioned constituent elements of the housing.

The member in which the gasket is provided has a flat surface to prevent damage to the gasket, and the gasket is mainly provided in the housing frame in consideration of space restriction.

As a result, the case frame may include the gasket in the upper and lower flanges by using a special and expensive work in the manufacturing process, thereby preventing damage to the foam gasket.

Further, since the tolerance of assembling the gasket is small and the defect rate is high, it is difficult to accelerate the transfer speed in the machining process in consideration of the tolerance, and it may be expensive to machine the groove for providing the gasket.

The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Disclosure of Invention

Technical problem

Exemplary embodiments of the present invention are directed to provide a battery module having a case that may be formed through a simple process using a low-cost configuration, and a vehicle including the same.

Technical scheme

An exemplary embodiment of the present invention provides a battery module including: a housing configured to include a base plate, a housing frame, and a cover plate; two or more battery cells; and gaskets interposed between the case frame and the base plate and between the case frame and the cover plate.

In the battery module, the upper flange of the case frame and the lower flange of the case frame have a stepped shape to form a recessed portion opened toward the inside of the case frame, and the gasket is disposed in the recessed portion. The upper flange may face the cover plate and the lower flange may face the base plate.

An exemplary embodiment of the present invention provides a battery module having upper and lower parts each having a depressed portion or a gasket rim (gasketrim) communicating with (opening toward) an inner space of a case frame. The gasket may be seated in the recess portion.

Specifically, the gasket may be interposed between the bottom surface of the recessed portion and the base plate or the lid plate.

In the present invention, the gasket arrangement ensures sufficient sealing of the case, prevents leakage of the electrolyte solution or the coolant from the inside of the case to the outside, or prevents inflow of water or oil from the outside of the case to the inside.

Further, in the present invention, the gasket arrangement may have a protection effect against electromagnetic influence, in particular, a protection against electromagnetic interference (EMC/EMI protection). In the present invention, the concave portion can achieve a higher conveying speed in the machining process in consideration of tolerance and the like, as compared with a general groove which is not opened to the inner space of the housing.

According to an exemplary embodiment of the invention, the gasket may be attached to the base plate or the cover plate. Thus, the gasket may comprise an adhesive layer or may be provided with a material having at least temporary adhesive properties.

When the gasket is provided on the base plate and the cover plate, handling of the gasket provided on the base plate and the cover plate is reduced in consideration of the fact that the base plate and the cover plate are assembled as one of the final steps in the assembly process. Therefore, damage to the gasket can be effectively prevented in the assembly process of the battery module.

Furthermore, it is not necessary to provide a conventional jig for handling the gasket, while preventing damage to the gasket during the assembly process, thereby reducing the cost of the manufacturing process.

The gasket may be, for example, a foam gasket, and the foaming agent forming the gasket may be provided directly on the base plate and the lid plate.

Conventional gaskets are cut from a flat sheet to allow sealing between multiple surfaces, while in-situ formed foam gaskets (FIPFG) are provided directly on either surface without such a forming process. Therefore, the manufacturing time and cost can be greatly reduced.

In the FIPFG process, liquid blowing agents are typically used. The thixotropic nature of the blowing agent ensures a stable seal even in complex and atypical areas.

In other words, by using a robot technique suitable for a product to be sealed, a complicated three-dimensional sealing shape and irregular sectional variation can be realized and it is possible to stably seal it.

According to another embodiment of the present invention, a width of the depression portion is in a range of 1:5 to 1:2 with respect to a total width of each of the upper and lower flanges.

Implementing the dimensions of the recessed portion within this range ensures the mechanical integrity of the housing frame. When this ratio is greater than 1:2, the flange will not have sufficient mechanical integrity. When the ratio is less than 1:5, the flange is too small to properly seat the gasket.

The total width of the upper flange is defined as the distance from the inside of the housing frame to the outside of the housing frame. The upper frame means a small portion of the inner surface of the case directly facing or contacting the cover plate.

In a relationship that may be independent of but combined with the foregoing exemplary embodiment, the width of the recessed portion may be set in a range of 3:1 to 1.2:1 with respect to the width of the gasket.

Thus, a desired arrangement between the individual components of the housing can be achieved within wider tolerances than with a normal groove which is not open towards the interior space of the housing. As a result, the proportion of defective products can be reduced.

When the ratio is more than 3:1, the manufacturing cost for forming the concave portion is increased without improving the sealing function of the gasket. When the ratio is less than 1.2:1, inconsistency between the gasket and the depressed portion may occur in the process, resulting in an increase in manufacturing loss.

According to another exemplary embodiment, which may be combined with any or all of the above exemplary embodiments, a depth of the concave portion with respect to a height of the gasket is in a range of 1:1.1 to 1: 2.

That is, the height of the gasket is slightly larger than the depth of the recessed portion. For the purpose of the present invention, the gasket may be generally formed of an elastic material, thus ensuring a stable seal even when the tolerance is further increased. Furthermore, the proportion of products to be joined can be reduced.

When the ratio is less than 1:1.1, the gasket cannot sufficiently seal the housing, and when the ratio is greater than 1:2, the coupling between the housing frame and the base plate or the cover plate cannot be properly performed.

According to another exemplary embodiment of the present invention, the recess portion may include a flange surface extending vertically on an inner side of the case frame, and the circumferential protrusion may be provided on the flange surface of the recess portion.

The gasket may be disposed such that the center thereof is located at an upper portion of the circumferential protrusion. The circumferential protrusion may have a height h2 and the recessed portion may have a height h 3. The ratio of height h3 to height h2 may be in the range of 2:1 to 5: 1.

As a result, the entire sealing surface of the gasket can be significantly increased. When the ratio is more than 5:1, the sealing surface cannot be increased. When the ratio is less than 2:1, the case cannot be properly closed.

An exemplary embodiment of the present invention provides a vehicle including the above battery module.

Advantageous effects

As described above, according to the exemplary embodiments of the present invention, it is possible to effectively reduce manufacturing costs, improve process efficiency, and improve sealing performance of a case.

Drawings

Fig. 1 illustrates a perspective view of a battery module according to an exemplary embodiment of the present invention.

Fig. 2 illustrates a partially exploded cross-sectional view of a battery module case according to an exemplary embodiment of the present invention.

Fig. 3 illustrates an exploded perspective view of a housing according to another exemplary embodiment of the present invention.

Fig. 4 shows a partially exploded cross-sectional view of the housing shown in fig. 1.

Fig. 5 illustrates a partially exploded cross-sectional view of a housing according to another exemplary embodiment of the present invention.

Fig. 6 shows an enlarged view of a portion according to the exemplary embodiment shown in fig. 5.

Fig. 7 shows a perspective view of an upper flange in the housing frame according to the exemplary embodiment shown in fig. 5.

Detailed Description

In the following detailed description, only certain exemplary embodiments of the present invention have been shown and described, simply by way of illustration.

As those skilled in the art will recognize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive. Like reference numerals refer to like elements throughout the specification.

In this specification, redundant description of the same constituent elements will be omitted.

In the present specification, it will be understood that, when one component is referred to as being "connected" or "coupled" to another component, it may be directly connected or coupled to the other component or may be connected or coupled to the other component with the other component interposed therebetween. In the present specification, it will be understood that, when one component is referred to as being "directly connected or coupled" to another component, it may be connected or coupled to the other component without the other component interposed therebetween.

It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

The singular forms will include the plural forms unless the context clearly dictates otherwise.

It will be further understood that the terms "comprises" and "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof.

Further, as used herein, the term "and/or" includes any combination of items or any of a plurality of listed items. In the present specification, "a or B" may include "a", "B" or "a and B".

As shown in fig. 1, the battery module 100 may include a plurality of battery cells 10 arranged in one direction and a heat exchange member 110 provided adjacent to the lower surfaces of the battery cells 10.

A pair of end plates 18 are provided to face the wide surfaces of the battery cells 10 on the outside of the battery cells 10, and a connecting plate 19 is provided to connect the pair of end plates 18 to fix the battery cells 10 together. The fastening portions 18a provided at opposite sides of the battery module 100 are fastened to the base plate 31 by bolts 40. The base plate 31 constitutes a bottom surface of the housing 30. Other constituent elements of the housing, such as the cover plate and the housing frame, are not shown in fig. 1.

An elastic member 120 made of an elastic material such as rubber may be interposed between the base plate 31 and the heat exchange member 110. Here, each battery cell 10 may have an angular shape (or a rectangular shape), and the battery module 100 is formed by stacking the battery cells 10 over a wide surface thereof.

In addition, each battery cell 10 includes a battery case configured to receive an electrode assembly and an electrolyte therein. The battery case is closed and sealed by the cap assembly 14.

The cap assembly 14 includes positive and negative terminals 11 and 12 having different polarities and a vent hole 13. The vent hole 13 corresponds to a safety mechanism of each battery cell 10, and serves as a passage through which gas generated in the battery cell 10 is discharged to the outside of the battery cell 10.

The positive terminal 11 and the negative terminal 12 of the battery cells 10 adjacent to each other may be electrically connected by a bus bar 15, and the bus bar 15 may be fixed by a nut 16 or the like. Therefore, the battery module 100 may be provided by electrically connecting the plurality of battery cells 10 into a bundle, and may be used as a power supply unit.

A rechargeable battery, particularly a rechargeable lithium battery, may be used as the battery cell 10. The battery module 100 may be a 48V battery for a vehicle.

Fig. 2 shows a cross-sectional view of a housing 30 according to an exemplary embodiment of the present invention. The housing 30 includes a base plate 31, a housing frame 32, and a cover plate 33.

Each component of the housing 30 may be made of a rigid material, for example a metal such as stainless steel or aluminum. The housing frame 32 includes an upper flange configured to face the inner surface of the cover plate 33 and a lower flange configured to face the inner surface of the base plate 31.

The gasket 50 may be interposed between the case frame 32 and the cover plate 33 and between the case frame 32 and the base plate 31. In particular, the gasket 50 may be provided in the recess portion 60, and the recess portion 60 communicates with the inner space of the housing 30 at the upper and lower flanges or is opened toward the inner space of the housing 30.

According to the present exemplary embodiment, the recessed portion 60 includes a flange surface 61 and an end surface 62. The gasket 50 may be disposed in close contact with the end surface 62 of the recess portion 60, but the present invention is not limited thereto.

Here, the flange surface 61 may extend substantially perpendicular to the inner surface of the case frame 32, and the end surface 62 may extend substantially in the same direction as the inner surface of the case frame 32.

However, the flange surface 61 and the end surface 62 are not necessarily limited thereto. The concave portion 60 can be easily formed at a high speed in a separate process.

The gasket 50 may be formed of an elastomeric material, such as an elastomer, for example, a polyolefin, an ethylene-propylene-diene-monomer polymer (EPDM). According to an exemplary embodiment of the present invention, the gasket 50 may be a foam gasket. The gasket 50 may be attached to the inner surface of the base plate 31 and the inner surface of the lid plate 33.

Accordingly, the gasket 50 may be at least temporarily adhered between the base plate 31 and the cover plate 33, or may include an adhesive film (not shown) provided between the base plate 31 and the cover plate 33.

For example, the gasket 50 may be a tape including an adhesive surface, and the tape may be adhered to the base plate 31 and the cover plate 33 before the finishing process of the case 30.

According to the exemplary embodiment of fig. 1, as shown in fig. 2, the recessed portion 60 has a width of about one-third with respect to the entire width of the upper flange of the case frame 32. The recessed portion 60 of the lower flange facing the base plate 31 also has the above-described dimensions, but the present invention is not limited thereto.

Further, according to the embodiment of the present invention, the ratio of the width of the gasket 50 to the width of the concave portion 60 is about 1: 2. Since the gasket 50 may be made of an elastic material, the height of the gasket 50 may be 1.1 to 2 times the depth of the recess portion 60 to ensure reliable sealing of the inner space of the housing 30.

Fig. 3 illustrates an exploded perspective view of a housing 30 according to another exemplary embodiment of the present invention. The cover plate 33 is shown as translucent to be seen in the drawings.

Here, the gasket 50 attached to the inner surfaces of the base plate 31 and the lid plate 33 has a cylindrical band shape (strip shape). During the manufacturing process, the case frame 32 is disposed on the upper side of the base plate 31, and the cover plate 33 is disposed on the upper side of the case frame 32.

Fig. 4 shows a cross-sectional view of a portion of the housing 30 shown in fig. 1. Here, the ratio of the width of each concave portion 60 to the entire width of the upper and lower flanges of the case frame 32 is about 1: 2. The gasket 50 is provided in the recess portion 60 to seal the inner space of the case 30 by the coupling of the base plate 31, the case frame 32, and the cover plate 33.

Fig. 5 shows a cross-sectional view of a portion of a housing 30 according to another exemplary embodiment of the present invention. Fig. 6 shows an enlarged view of fig. 5. Fig. 5 shows the upper flange of the housing frame 32 including the recessed portion 60 and the gasket 50.

Basically, fig. 5 follows the exemplary embodiment of fig. 2, except that a circumferential protrusion 63 is provided on the flange surface 61 of the recessed portion 60. The circumferential protrusion 63 may preferably be provided in a bar shape extending along the upper flange or the lower flange to form a closed curve, and the gasket 50 may be disposed at an upper center side of the circumferential protrusion 63.

By such a structure, the total sealing surface of the gasket 50 can be increased by up to 20%. The circumferential projection 63 has a height h2 and the recessed portion 60 has a height h 3. The ratio of height h3 to height h2 is preferably in the range of 2:1 to 5: 1. In the exemplary embodiment shown in fig. 6, this ratio is about 3.75:1, but the invention is not limited thereto.

While the invention has been particularly shown and described with reference to a particular embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Symbol description:

30: the housing 31: base plate

32: the housing frame 33: cover plate

50: gasket 60: concave part

61: flange surface 62: end surface

63: circumferential projection

Claims

1. A battery module, comprising:

a plurality of battery cells;

a housing configured to include a base plate, a housing frame, and a cover plate; and

a gasket interposed between the case frame and the base plate and between the case frame and the cover plate,

wherein each of an upper flange of the case frame facing the cover plate and a lower flange of the case frame facing the base plate has a stepped shape forming a recessed portion opened to an inner side of the case frame such that the recessed portion formed at the upper flange is recessed with respect to a top surface of the upper flange and the recessed portion formed at the lower flange is recessed with respect to a bottom surface of the lower flange, and

the gasket is disposed in the recessed portion.

2. The battery module of claim 1, wherein

The gasket is attached to the base plate and the cover plate.

3. The battery module of claim 2, wherein

The gasket is a foam gasket formed by providing a foaming agent to each of the base plate and the lid plate.

4. The battery module of claim 1, wherein

The width of the recessed portion has a range of 1:5 to 1:2 with respect to the total width of the upper flange and the lower flange.

5. The battery module of claim 1, wherein

The width of the recessed portion has a range of 3:1 to 1.2:1 relative to the width of the gasket.

6. The battery module of claim 1, wherein

The depth of the recessed portion has a range of 1:1.1 to 1:2 with respect to the height of the gasket.

7. The battery module of claim 1, wherein

The recessed portion includes a flange surface extending in a direction intersecting the inner side of the case frame and a circumferential protrusion provided on the flange surface of the recessed portion.

8. The battery module of claim 7, wherein

The gasket is disposed on an upper side of the circumferential protrusion.

9. The battery module of claim 8, wherein

The circumferential projection has a height h2, the recessed portion has a height h3, and

the ratio of the height h3 to the height h2 is in the range of 2:1 to 5: 1.

10. A vehicle comprising the battery module according to any one of claims 1 to 9.