CN110168768B - Battery module and vehicle including the same - Google Patents

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 of a battery module housing has a special design and a vehicle including the same.

Background technique

Rechargeable batteries differ from primary batteries in that charging and discharging can be repeated, and primary batteries only provide an irreversible transformation 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, 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 electrodes components.

The electrolyte solution is injected into the case so that the battery can be charged and discharged through the electrochemical reaction 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 comprising a plurality of unit cells connected in series or parallel to provide high energy density for operating eg hybrid vehicles.

That is, the battery module may interconnect a plurality of unit battery cells according to the amount of power required to realize a high-power rechargeable battery, such as for an electric vehicle. Large battery systems used in electric vehicles can include 3 to 1000 battery cells. Such battery cells may be provided as a plurality of battery modules in which 10 to 20 battery cells are included in a general housing.

Battery modules can be configured as block or modular. In the case of the block type, each battery may be coupled to a common current collector and a common battery management system, and may have a housing.

In the case of the modular type, a plurality of battery cells are connected to constitute a sub-module, and a plurality of sub-modules are connected to constitute one of the modules. Battery management functions may be implemented at least partially at the module or sub-module level, thereby improving compatibility.

One or more battery modules may be mechanically and electrically integrated, installed with a thermal management system, and connected to one or more electrical consumers to form a battery system.

A battery system can have three main sealing areas, such as case gaskets, gaskets for electronics such as connectors, and gaskets for cooling systems. The case gasket protects the interior space of the case from liquids or dust and protects its environment from high voltages throughout the cycle life of the battery system.

When applied to a vehicle, the battery should be able to withstand a pressure of about 10,000 Pa for a minimum of 30 minutes, preventing the inflow of dust, etc. In addition, the case gasket should have good durability against contact with oil contamination or electrolyte solution leaking from the battery cells.

On the other hand, the housing gasket must be able to open and close so that simple defects such as loose coupling of 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, the manufacturing process of each housing gasket needs to be optimized. For example, the housing may include auxiliary constituent elements for speeding up the fastening process.

The case of the battery may include three constituent elements, ie, a base plate, a case frame, and a cover plate. Foam gaskets may be provided in grooves or planes between the aforementioned constituent elements of the housing.

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

As a result, the housing frame may include gaskets in the upper and lower flanges through the use of special and expensive workpieces in the manufacturing process to prevent damage to the foam gaskets.

In addition, due to the tight tolerance in assembling the gasket and the high defect rate, it is difficult to speed up the conveying speed in the machining process in consideration of the tolerance, and machining the groove for providing the gasket can be expensive.

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.

SUMMARY OF THE INVENTION

technical problem

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

Technical solutions

An exemplary embodiment of the present invention provides a battery module including: a case configured to include a base plate, a case frame, and a cover plate; two or more battery cells; and a gasket interposed between the housing frame and the base plate and between the housing 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 a gasket is provided 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 an upper portion and a lower portion each having a recessed portion or a gasket communicating with (opening toward) an inner space of a case frame Gasket rim. A gasket may be seated in the recessed portion.

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

In the present invention, the gasket arrangement ensures adequate sealing of the case, preventing leakage of electrolyte solution or coolant from the inside of the case to the outside, or preventing water or oil from flowing into the inside from the outside of the case.

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

According to an exemplary embodiment of the present 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, the handling of the gasket provided on the base plate and the cover plate is reduced considering that the base plate and the cover plate are assembled as one of the last steps in the assembly process. Therefore, damage to the sealing gasket can be effectively prevented in the assembly process of the battery module.

Furthermore, there is no need to provide conventional jigs 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 blowing agent forming the gasket may be provided directly on the base plate and the cover plate.

Whereas traditional gaskets are cut from flat sheets to allow sealing between multiple surfaces, form-in-place form gaskets (FIPFG) are provided directly on either surface without such forming craft. Therefore, the manufacturing time and cost can be greatly reduced.

In the FIPFG process, liquid blowing agents are usually used. The thixotropic properties of the blowing agent ensure stable sealing even in complex and atypical areas.

In other words, complex three-dimensional seal shapes and irregular cross-sectional changes can be achieved and stably sealed by using robotics suitable for products that need to be sealed.

According to another embodiment of the present invention, the width of the recessed portion is in the range of 1:5 to 1:2 with respect to the 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 the 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 overall 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 represents the small portion of the housing that directly faces or contacts the inner surface of the cover.

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

Thus, the desired arrangement between the various parts of the housing can be achieved within wider tolerances compared to ordinary grooves that are 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 recessed portion may increase without improving the sealing function of the gasket. When the ratio is less than 1.2:1, inconsistency between the gasket and the recessed portion may occur in the process, resulting in increased manufacturing losses.

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

That is, the height of the gasket is slightly larger than the depth of the recessed portion. For the purposes of the present invention, the gasket may generally be formed of an elastic material, thus ensuring a stable seal even when tolerances are 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 more 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 recessed portion may include a flange surface extending vertically on the inner side of the housing frame, and the circumferential protrusion may be provided on the flange surface of the recessed portion.

The gasket may be arranged such that its center 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 h3. 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 greater than 5:1, the sealing surface cannot be increased. When the ratio is less than 2:1, the housing cannot be properly closed.

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

beneficial effect

As described above, according to the exemplary embodiments of the present invention, the manufacturing cost can be effectively reduced, the process efficiency can be improved, and the sealing performance of the housing can be improved.

Description of drawings

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

2 shows a partial cutaway view of a battery module housing according to an exemplary embodiment of the present invention.

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

FIG. 4 shows a partial cutaway view of the housing shown in FIG. 1 .

Figure 5 shows a partial cutaway view of a housing according to another exemplary embodiment of the present invention.

FIG. 6 shows an enlarged view of a portion of the exemplary embodiment shown in FIG. 5 .

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

Detailed ways

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

As those skilled in the art would realize, 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 restrictive. The same reference numerals refer to the same elements throughout the specification.

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

In this specification, it will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or it can be connected or coupled to the other element such that otherwise components are inserted in between. In this specification, it will be understood that when an element is referred to as being "directly connected or coupled" to another element, it can be connected or coupled to the other element without the other element interposed therebetween.

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

The singular includes the plural unless the context clearly dictates otherwise.

It will also be understood that the terms "comprising" or "having" used in this specification designate the presence of stated features, numbers, steps, operations, components, parts or combinations thereof, but do not exclude one or more other features, numbers The presence or addition of , steps, operations, components, parts, or combinations thereof.

Further, as used herein, the term "and/or" includes any combination of any of the plurality of items or any of the plurality of listed items. In this 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 surface of the battery cells 10 .

A pair of end plates 18 are provided to face the wide surfaces of the battery cells 10 outside the battery cells 10, and connecting plates 19 are provided to connect the pair of end plates 18 to secure the battery cells 10 together. Fastening portions 18 a provided on opposite sides of the battery module 100 are fastened to the base plate 31 by bolts 40 . The base plate 31 constitutes the bottom surface of the case 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 of the battery cells 10 may have an angular (or rectangular shape), and the battery module 100 is formed by stacking the battery cells 10 on a wide surface thereof.

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

The cap assembly 14 includes a positive terminal 11 and a negative terminal 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 the 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 can be provided by electrically connecting the plurality of battery cells 10 in a bundle, and can be used as a power supply unit.

A rechargeable battery, particularly a rechargeable lithium battery, can 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 the housing 30 according to an exemplary embodiment of the present invention. The case 30 includes a base plate 31 , a case frame 32 and a cover plate 33 .

Each component of the housing 30 may be made of a rigid material, such as a metal such as stainless steel or aluminum. The case 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 a recessed portion 60 that communicates with or opens toward the inner space of the housing 30 at the upper and lower flanges.

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 provided in close contact with the end surface 62 of the concave 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 to this. The recessed portion 60 can be easily formed at a high speed in a single processing process.

The gasket 50 may be formed of an elastic material, eg, an elastomer such as polyolefin, ethylene-propylene-diene-monomer (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 cover plate 33 .

Therefore, 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 prior to the finishing process of the housing 30 .

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

Furthermore, according to the embodiment of the present invention, the ratio of the width of the gasket 50 to the width of the recessed 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 recessed portion 60 to ensure reliable sealing of the inner space of the housing 30 .

FIG. 3 shows an exploded perspective view of a housing 30 according to another exemplary embodiment of the present invention. The cover plate 33 is shown translucent for viewing in the drawings.

Here, the gasket 50 attached to the inner surfaces of the base plate 31 and the cover plate 33 has the shape of a cylindrical belt (stripe). During the manufacturing process, the case frame 32 is provided on the upper side of the base plate 31 , and the cover plate 33 is provided 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 recessed portion 60 to the entire width of the upper and lower flanges of the housing frame 32 is about 1:2. The gasket 50 is provided in the recessed portion 60 to seal the inner space of the case 30 through 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 the 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 or lower flange to form a closed curve, and the gasket 50 may be provided on the upper center side of the circumferential protrusion 63 .

With such a configuration, the total sealing surface of the gasket 50 can be increased by up to 20%. The circumferential protrusion 63 has a height h2, and the recessed portion 60 has a height h3. 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, the ratio is about 3.75:1, but the invention is not limited thereto.

Although the present invention has been particularly shown and described with reference to specific embodiments of the invention, 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. The scope of the invention is defined by the claims.

Symbol description:

30: Housing 31: Base plate

32: Housing frame 33: Cover plate

50: Gasket 60: Recessed part

61: Flange surface 62: End surface

63: Circumferential protrusions

Claims (10)

1. A battery module, comprising: multiple battery cells; a housing configured to include a base plate, a housing frame, and a cover plate; and a gasket interposed between the casing frame and the base plate and between the casing 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 each has a stepped shape that is formed toward the shell A recessed portion opened at the inner side of the body frame such that the recessed portion formed at the upper flange is recessed with respect to the top surface of the upper flange and the recessed portion formed at the lower flange is recessed with respect to the top surface of the upper flange the bottom surface of the lower flange is recessed, and The gasket is provided 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 supplying a blowing agent to each of the base plate and the cover plate. 4. The battery module of claim 1, wherein The width of the recessed portion is in the 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 is in the range of 3:1 to 1.2:1 with respect to the width of the gasket. 6. The battery module of claim 1, wherein The depth of the recessed portion is in the 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 housing 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 provided on the upper side of the circumferential protrusion. 9. The battery module of claim 8, wherein the circumferential protrusion 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 of any one of claims 1 to 9.

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