KR20230109928A - Battery module with improved safety - Google Patents

Abstract

The present invention discloses a battery module in which safety can be secured by stably maintaining a welded portion even when a thermal event such as fire or venting gas occurs inside the battery module. A battery module according to an aspect of the present invention includes a cell assembly including one or more battery cells; a body frame configured to accommodate the cell assembly in an inner space and having an open portion formed on at least one side; and end frames welded to the open portion of the body frame and having welded portions formed at different positions along a coupling direction to the body frame.

Description

Battery module with improved safety}

The present invention relates to a battery, and more particularly, to a battery module with improved safety for welding, a battery pack including the battery module, and an automobile.

As the demand for portable electronic products such as laptop computers, video cameras, and mobile phones rapidly increases, and commercialization of robots and electric vehicles begins in earnest, research on high-performance secondary batteries capable of repeated charging and discharging is being actively conducted.

Currently commercially available secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries are in the limelight because of their advantages of free charge and discharge, very low self-discharge rate, and high energy density, as the memory effect hardly occurs compared to nickel-based secondary batteries.

These lithium secondary batteries mainly use lithium-based oxides and carbon materials as positive electrode active materials and negative electrode active materials, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such a positive electrode active material and a negative electrode active material are disposed with a separator therebetween, and an exterior material that seals and houses the electrode assembly together with an electrolyte, that is, a battery case.

In general, lithium secondary batteries can be classified into a can-type secondary battery in which an electrode assembly is embedded in a metal can and a pouch-type secondary battery in which an electrode assembly is embedded in a pouch of an aluminum laminate sheet, depending on the shape of an exterior material.

Recently, secondary batteries have been widely used for driving or energy storage not only in small devices such as portable electronic devices, but also in medium and large-sized devices such as electric vehicles and energy storage systems (ESSs). A plurality of these secondary batteries may constitute one battery module in a form in which a plurality of them are stored together in a module case in a state in which they are electrically connected. In addition, a plurality of such battery modules may be connected to form one battery pack.

As such, in a battery module or battery pack in which a plurality of secondary batteries (battery cells) or a plurality of battery modules are concentrated in a narrow space, securing safety when a thermal event occurs is a very important task. In particular, when an event such as thermal runaway occurs in any one battery cell, high-temperature gas, flame, or heat may be generated and discharged. At this time, pressure inside the module case increases due to high-temperature venting gas or flame, and as a result, the module case may be damaged.

In particular, a welded portion may be formed in the module case, and high-temperature venting gas or flame may cause a problem of deteriorating or breaking the welded portion. Moreover, when the welding part is broken, as external oxygen is introduced into the module case, the flame inside the battery module may increase. And, this may lead to fire or explosion of the battery module or battery pack. A fire or explosion of such a battery module or battery pack may cause damage to human life as well as property damage. For example, when a fire or explosion occurs in a battery pack for an electric vehicle, the safety of a user, such as a driver, may be threatened.

Accordingly, the present invention has been devised to solve the above problems, and an object of the present invention is to provide a battery module that can ensure safety by stably maintaining a welded portion even when a thermal event such as fire or venting gas occurs inside the battery module, and a battery pack including the same and a vehicle.

However, the technical problem to be solved by the present invention is not limited to the above problem, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

A battery module according to an aspect of the present invention for achieving the above object includes a cell assembly including one or more battery cells; a body frame configured to accommodate the cell assembly in an inner space and having an open portion formed on at least one side; and end frames welded to the open portion of the body frame and having welded portions formed at different positions along a coupling direction to the body frame.

Here, the end frame may include a front frame and a rear frame, and may be welded to the front and rear of the body frame, respectively.

In addition, the end frame may have four corners, and a welded part may be formed at at least one corner among the four corners.

In addition, the welding portion may be configured in a bent line shape.

In addition, the welding part may be formed in a line shape bent at at least two corners among a plurality of corners provided in the end frame.

In addition, the end frame may include a protrusion formed to protrude in the coupling direction, and the body frame may include a concave portion configured to allow the protrusion to be inserted and engaged.

In addition, the body frame may be configured in the form of a clad metal having an inner layer and an outer layer.

In addition, the inner layer may include a SUS material, and the outer layer may include an aluminum material.

In addition, in a state in which at least a portion of the end frame is seated on the outer surface of the inner layer, an end portion of the seated portion may be welded to the outer layer.

In addition, the end frame may include an end plate and a side plate protruding from a corner portion of the end plate toward the body frame and having the weld portion formed at an end thereof.

In addition, a venting hole may be formed in the side plate of the end frame.

In addition, the battery module according to the present invention may further include a venting unit provided outside the side surface of the end frame where the venting hole is formed so that the venting gas discharged from the venting hole can move.

In addition, a battery pack according to another aspect of the present invention for achieving the above object includes a battery module according to the present invention.

In addition, a vehicle according to another aspect of the present invention for achieving the above object includes a battery module according to the present invention.

According to the present invention, even if a thermal event such as venting gas or flame occurs inside the battery module, safety of the battery module can be secured.

In particular, according to one aspect of the present invention, even if the internal pressure of the module case increases, the welding portion can be stably maintained without being damaged or damaged.

Furthermore, according to an exemplary embodiment of the present invention, the welding section of the welded portion is enlarged, so that the weldability of the welded portion is improved and the tensile stress may be increased.

Therefore, in the battery module, it is possible to effectively prevent the spread of fire due to the introduction of oxygen or the like through the damaged or damaged portion of the module case.

In addition, the present invention may have various other effects, which will be described in each implementation configuration, or descriptions of effects that can be easily inferred by those skilled in the art will be omitted.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention serve to further understand the technical idea of the present invention, the present invention is described in such drawings. It should not be construed as limited only.
1 is a combined perspective view schematically showing the configuration of a battery module according to an embodiment of the present invention.
2 is an exploded perspective view of some components of the battery module of FIG. 1 .
FIG. 3 is an enlarged view of a portion of the top surface of the battery module of FIG. 1 .
4 and 5 are top views schematically showing some components of a battery module according to different embodiments of the present invention.
6 is a cross-sectional view of some components of a battery module according to an embodiment of the present invention.
7 is an exploded perspective view schematically illustrating some configurations of a battery module according to another embodiment of the present invention.
8 is a view showing a partial cross-sectional configuration in a state in which the battery module of FIG. 7 is coupled.
9 is a cross-sectional view schematically showing some configurations of a body frame according to another embodiment of the present invention.
10 is a perspective view schematically illustrating the configuration of a battery module according to another embodiment of the present invention.
11 is a perspective view schematically illustrating the configuration of a battery module according to another embodiment of the present invention.
FIG. 12 is a perspective view schematically illustrating the configuration of the end frame included in FIG. 11 from another angle.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to ordinary or dictionary meanings, and the inventors should appropriately define the concept of terms in order to best explain their invention. It should be interpreted as meanings and concepts consistent with the technical spirit of the present invention based on the principle that they can be defined.

Therefore, since the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention, various equivalents and modifications that can replace them at the time of the present application It should be understood that there may be.

1 is a combined perspective view schematically illustrating the configuration of a battery module according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of some components of the battery module of FIG. 1 .

Referring to FIGS. 1 and 2 , the battery module according to the present invention includes a cell assembly 100 , a body frame 200 and an end frame 300 .

The cell assembly 100 may include one or more battery cells 110 . Moreover, the cell assembly 100 may include a plurality of battery cells 110 . Here, each battery cell 110 may mean a secondary battery. A secondary battery may include an electrode assembly, an electrolyte, and a battery case. In particular, the battery cell 110 included in the cell assembly 100 may be a pouch type secondary battery. However, other types of secondary batteries, such as cylindrical batteries or prismatic batteries, may also be employed in the cell assembly 100 of the present invention.

A plurality of secondary batteries may form the cell assembly 100 in a stacked form. For example, a plurality of secondary batteries may be stacked side by side in a horizontal direction (X-axis direction in the drawing) in a state where each is erected in a vertical direction (Z-axis direction in the drawing).

Each battery cell 110 may include an electrode lead. In this case, the electrode leads may be located at both ends or at one end of each battery cell 110 . The plurality of battery cells 110 may be electrically connected to each other in series and/or parallel through electrode leads. At this time, the electrode leads of each battery cell 110 may be directly connected by contacting each other, or may be indirectly connected through a bus bar or the like. Meanwhile, a secondary battery with electrode leads protruding in both directions is referred to as a bidirectional cell, and a secondary battery with electrode leads protruding in one direction may be referred to as a unidirectional cell. In FIG. 2 and the like, an electrode lead protrudes in both directions, forward (-Y axis direction) and rear (+Y axis direction). However, the present invention is not limited by the specific type or form of the secondary battery, and various types of secondary batteries known at the time of filing the present invention may be employed in the cell assembly 100 of the present invention.

The body frame 200 may be configured to accommodate the cell assembly 100 in an internal space. For example, as shown in FIG. 2 , the body frame 200 may have a closed top, bottom, left and right sides. More specifically, the body frame 200 includes an upper frame, a lower frame, a left frame, and a right frame, and these four frames are formed in a plate shape, respectively, and may be combined or integrated with each other. In particular, when the four plate-shaped frames are configured in a tubular form integrated with each other, the body frame 200 may be referred to as a mono frame.

Also, the body frame 200 may have an open portion formed on at least one side. For example, as shown in FIG. 2 , the body frame 200 may have an open portion formed at the front. This open portion may be a portion for inserting the cell assembly 100 into the body frame 200 .

The end frame 300 may be coupled to the open portion of the body frame 200 . For example, in the embodiment of FIG. 2 , when the opening is formed in the front of the body frame 200, the end frame 300 may be coupled to the front opening of the body frame 200. In addition, the end frame 300 may close the inner space of the body frame 200 through a combination with the body frame 200 .

Furthermore, the end frame 300 may be coupled to the body frame 200 by welding. That is, the end frame 300 may be coupled to the open portion of the body frame 200, and a welding portion may be formed in a form in which at least a portion of the body frame 200 is welded.

For example, the end frame 300 may have a welded portion welded to the upper frame of the body frame 200, as indicated by A1 in FIG. 1 . In addition, the end frame 300 may be formed with a welded portion welded to the left frame of the body frame 200, as indicated by A2 in FIG. In addition, although not shown in FIG. 1 , the end frame 300 may have a welded portion welded to the lower frame and/or the right frame of the body frame 200 .

In particular, in the present invention, the end frame 300 may be welded at different positions along the direction of coupling to the body frame 200 . This will be described in more detail with further reference to FIG. 3 .

FIG. 3 is an enlarged view of a part of the top surface of the battery module of FIG. 1 . In particular, FIG. 3 may be a top view showing a front portion of the battery module of FIG. 1 .

Referring to FIG. 3 , the end frame 300 may form a welded portion at portions C1 and C2 of the body frame 200 (upper frame). In this case, the C1 part and the C2 part may be located at different parts along the front-back direction (Y-axis direction of the drawing) of the battery module. Here, the front-back direction of the battery module may be said to be the same as the coupling direction of the end frame 300 and the body frame 200 . For example, the end frame 300, as indicated by the arrow B1 in FIG. 2, may be positioned at the front of the body frame 200 and moved in a rearward direction, that is, moved in the +Y axis direction. Therefore, at this time, the coupling direction of the end frame 300 and the body frame 200 may be referred to as the +Y axis direction. In addition, it can be said that the welded parts of the end frame 300 and the body frame 200 are respectively formed at different positions along the coupling direction, as indicated by C1 and C2 in FIG. 3 . That is, in the embodiment of FIG. 3, on one surface (upper surface) of the battery module, welds C1 and C2 are provided together. In this case, the weld C1 is along the coupling direction compared to the weld C2. It can be said to be located in the central part (inside) of the battery module.

According to this embodiment of the present invention, the bonding strength of the welded portion can be further improved. In particular, in the case of the above embodiment, since the welding parts of one upper frame are distributed and located in a wide area in the coupling direction of the end frame 300, the joint between the end frame 300 and the body frame 200. Tensile stress can be improved. In addition, according to the above embodiment configuration of the present invention, the configuration of forming a longer welding length of the weld portion can be more easily implemented.

The end frame 300 may include a front frame 301 and a rear frame 302 . For example, as shown in FIGS. 1 and 2, the end frame 300 may include a front frame 301 positioned on the front side (−Y axis direction of the drawing) of the battery module and a rear frame 302 positioned on the rear side (+Y axis direction of the drawing) of the battery module. In addition, the body frame 200 may be configured in a mono frame shape, and open portions may be formed on the front side and the rear side, respectively. At this time, the front frame 301 may be welded to the front opening of the body frame 200 . In addition, the rear frame 302 may be welded to the rear opening of the body frame 200 .

Here, each of the front frame 301 and the rear frame 302 is formed with a welded portion, and each welded portion may be configured to include portions having different welding positions along the coupling direction. For example, the weld portion formed on the upper frame of the front frame 301 may be configured to include portions having different welding positions along the coupling direction. In addition, the welded portion of the rear frame 302 may also be configured to have welded portions on one surface at different positions along the joining direction.

According to this embodiment of the present invention, when the body frame 200 is configured in the form of a mono frame and the end frame 300 is coupled to the double-sided open portion, the bonding force by welding can be further improved. Thus, the module case including the body frame 200 and the end frame 300 can be more structurally stabilized.

The end frame 300 may be configured to have four corners. For example, in the configurations of FIGS. 1 and 2 , the front end frame 300 , that is, the front frame 301 may be configured in a substantially rectangular shape when viewed from the front side. Accordingly, the front frame 301 may be said to have a total of four corners, including corners at the top, bottom, left, and right sides, respectively.

In this configuration, the end frame 300, that is, the front frame 301 may have a welded portion formed at at least one of the four corners. In particular, as described above, the front frame 301 may have a welded portion formed at an upper corner thereof, as indicated by A1 in FIG. 1 . In addition, the front frame 301, as shown in the portion indicated by A2 in Figure 1, may be formed with a welded portion on the left corner. In addition, although not shown in the drawing, the front frame 301 may have a welded portion formed at a lower corner of the opposite side of A1. In addition, the front frame 301 may have a welded portion formed at the right corner of the opposite side of A2.

Furthermore, in the end frame 300 having four corners, welds may be formed at at least two or more corners. In particular, the welding portion may be formed at all four corners of the end frame 300 . That is, the end frame 300 may have welded portions formed on all of the upper, lower, left and right portions. In this case, the end frame 300 and the body frame 200 can be more stably coupled. In addition, in this case, leakage of venting gas or flame between the end frame 300 and the body frame 200 can be more effectively prevented.

In addition, the welding portion may be configured in a bent line shape.

For example, referring to the configuration of FIG. 3 when the battery module according to the present invention is viewed from above, the end frame 300 and the body frame 200 are welded to each other at the upper ends of each component, and from one side to the other side. It may be configured in the form of a line extending long. More specifically, the upper welded portion of the end frame 300 may be formed in a line shape extending from a portion where the left edge is located to a portion where the right edge is located.

At this time, the line formed at the welding part of the end frame 300, that is, the welding line, as indicated by W1 in FIG. 3, may be configured in a bent form. That is, when extending from one end to the other end, the welded part of the end frame 300 may not extend only in a straight line, but may extend in a line shape having a bent portion. In particular, the welded portion of the end frame 300 may be formed in a zigzag shape as shown in FIG. 3 . For example, in FIG. 3, the weld portion may include an inner weld portion (C1 portion) and an outer weld portion (C2 portion) extending in the X-axis direction and spaced apart by a predetermined distance in the coupling direction (Y-axis direction) of the end frame, and a front and rear weld portion (C3 portion) formed to extend in the Y-axis direction between the inner weld portion (C1 portion) and the outer weld portion (C2 portion). And, the welding portion may be configured in a form in which the C1 portion, the C3 portion, the C2 portion, and the C3 portion are sequentially and repeatedly formed.

According to this implementation configuration of the present invention, the length of the welded portion can be formed long. That is, referring to the embodiment of FIG. 3 , the length of the welding part may be longer than the width of the body frame 200 in the left and right directions. Thus, the bonding force between the end frame 300 and the body frame 200 can be increased. In particular, in the embodiment of FIG. 3, in addition to the welding sections formed in the left and right directions (X-axis direction) indicated by C1 and C2, there is a welding section formed in the front-back direction (Y-axis direction), such as the portion indicated by C3. Therefore, at one corner of the end frame 300 and the body frame 200, for example, the upper corner, a welding section may be formed much longer than the original length of the corner.

Meanwhile, in the exemplary configuration of FIG. 3 , each of the welding sections indicated by C1, C2, and C3 may be formed over a certain length to secure welding power. For example, the inside welded portion denoted C1 may be formed to have a length of 20 mm or more. In addition, the front and back welded portion indicated by C3 may be formed to have a length of 40 mm or more.

Meanwhile, in FIG. 3, as indicated by W1, a configuration in which the weld portion is formed in a substantially zigzag shape is shown, but the weld portion between the end frame 300 and the body frame 200 according to the present invention may be formed in various other shapes. This will be described in more detail with further reference to FIGS. 4 and 5 . Meanwhile, in the present specification, for each embodiment, detailed descriptions of parts to which descriptions of other embodiments can be applied identically or similarly are omitted, and description is focused on parts with differences.

4 and 5 are top views schematically showing some components of a battery module according to different embodiments of the present invention.

First, referring to FIG. 4 , the end frame 300 and the body frame 200 may be welded to each other through a welding portion having a wave shape, as indicated by W2 . That is, the welded portion between the end frame 300 and the body frame 200 may have a weld line extending generally in the left-right direction (X-axis direction) and curved in the front-back direction (Y-axis direction).

Even when according to this implementation configuration of the present invention, the welding section of the welding portion may be formed longer than the width of the body frame 200 in the left and right directions. Thus, bonding force between the body frame 200 and the end frame 300 may be improved.

In addition, referring to FIG. 5, the end frame 300 and the body frame 200 are welded to each other through a welding portion having a concave-convex shape, as indicated by W3, and the concave-convex portion may have a portion gradually widening in the joining direction. For example, as shown by A3 in FIG. 5, looking at one protrusion or concave portion in the welding line between the end frame 300 and the body frame 200, the protrusion of the end frame 300 may be configured to gradually widen in the +Y axis direction. In this case, the concave portion of the body frame 200 may also be configured to gradually widen in the +Y-axis direction so as to correspond to these protrusions.

According to this configuration of the present invention, it is possible to form a longer welding section length of the welding portion. Therefore, the bonding strength by welding between the end frame 300 and the body frame 200 can be further improved. In addition, according to the above embodiment, the protruding portion of the end frame 300 and the concave portion of the body frame 200 are engaged, and the bonding force can be increased by itself. In particular, according to the above embodiment, due to the meshed shape, the movement of the end frame 300 in the -Y axis direction (front) in the body frame 200 can be suppressed.

In addition to these embodiments, the welded portion may be formed in various other shapes.

The welding portion may be provided at at least two corners among a plurality of corners provided on the end frame 300 . Moreover, the welding portion may be configured in a line shape each bent at at least two corners. In particular, the welded portion may be formed at corners facing each other.

For example, between the end frame 300 and the body frame 200, the welded portion in the form of a bent line shown in FIGS. 3 to 5 may be provided at upper and lower corners, respectively. At this time, the end frame 300 and the body frame 200, the left edge and the right edge of the welding line in the form of a straight line can be formed. For example, in the side portion of the end frame, such as the portion indicated by A2 in FIG. 1, the welding portion may be configured in the form of a straight welding line.

According to this embodiment of the present invention, the welding section of the welding part is more sufficiently formed between the end frame 300 and the body frame 200, so that the bonding force can be stably secured at a certain level or more. The location of the welded part in the form of such a bent line may be appropriately determined in consideration of various factors, such as the configuration of the end frame 300 and the body frame 200, or the shape or arrangement of other components located inside or outside the end frame 300 and the body frame 200.

The end frame 300 may include a protruding portion P, as indicated by P in FIG. 2 . The protruding portion P may be formed to protrude in a coupling direction of the end frame 300, that is, in a direction in which the end frame 300 faces the body frame 200.

In addition, the body frame 200 may have a concave portion, as indicated by G1 in FIG. 2 , in a position and shape corresponding to the protruding portion P of the end frame 300 . That is, the body frame 200 may have a concave portion G1 so that the protruding portion P of the end frame 300 can be inserted and fastened. The concave portion G1 of the body frame 200 may be formed in a shape cut to correspond to the shape of the protruding portion P in the body frame 200 . For example, the concave portion G1 located in the front of the body frame 200 may be formed in a shape concavely cut to the rear (+Y-axis direction).

The end plate 310 and the body frame 200 may be configured so that at least one component supports another component. This will be described in more detail with further reference to FIG. 6 .

6 is a cross-sectional view of some components of a battery module according to an embodiment of the present invention. For example, FIG. 6 may be a cross-sectional configuration along line D1-D1′ of FIG. 1 .

Referring to FIG. 6 , the ends of the end frame 300 and the body frame 200 may come into contact with each other, as shown in A4. And, in this way, a welding portion may be formed by welding a contact portion between the end frame 300 and the body frame 200 . At this time, as shown in A5, a part of the end frame 300 may be configured to support the body frame 200. In particular, the rear end of the end frame 300 has a portion formed to protrude backward (in the +Y axis direction), and the front end of the body frame 200 is seated on the upper portion of the protruding portion of the end frame 300, and can be supported in the upward direction.

According to this configuration of the present invention, since the end frame 300 supports the body frame 200 in an upward direction (outward direction), the contact state between the end frame 300 and the body frame 200 can be stably maintained during the welding process. Therefore, weldability can be improved. Moreover, such a support structure of the end frame 300 may be formed in all corners of the end frame 300, such as the upper part, the lower part, the left part and the right part. In this case, since the protruding portion of the end frame 300 is inserted into the body frame 200, an insertion and fastening configuration between the end frame 300 and the body frame 200 may be implemented. Thus, mechanical coupling force between the end frame 300 and the body frame 200 may be improved.

Meanwhile, in the embodiment of FIG. 2, an embodiment in which a concave portion is formed in a form in which a part of the body frame 200 is cut is shown, but the present invention is not necessarily limited to this embodiment.

7 is an exploded perspective view schematically illustrating some configurations of a battery module according to another embodiment of the present invention. 8 is a view showing a partial cross-sectional configuration in a state in which the battery module of FIG. 7 is coupled. For example, it can be said that FIG. 8 shows a cross-sectional configuration of a line D2-D2′ in a state in which the battery module of FIG. 7 is coupled.

Referring to FIGS. 7 and 8 , a concave portion may be formed in the body frame 200 as indicated by G2 . The concave portion G2 may be formed in the body frame 200 in an inward direction. In this specification, the inward direction may refer to a direction toward the inside of the battery module unless otherwise specified. In the case of FIGS. 7 and 8 , the concave portion is formed in the upper frame of the body frame 200 . Therefore, it can be said that the concave portion is formed concavely from the upper surface (outer surface) of the upper frame in the downward direction (inward direction). In this embodiment, unlike the previous embodiment of FIG. 2 , the body frame 200 may not be cut or the cut size may be reduced to form the concave portion.

In this configuration, the protruding portion P of the end frame 300 may be seated on the outer surface of the concave portion G2 of the body frame 200 . That is, in the case of the concave portion G2 formed on the upper portion of the body frame 200, the protruding portion P may be seated on the upper portion. Also, as shown in FIG. 3 , the welded portion between the end frame 300 and the body frame 200 may be formed in a line shape bent along the uneven shape of the end frame 300 .

According to this embodiment of the present invention, most of the protrusions P of the end frame 300 may be supported in an outward direction (upward direction) by the concave portion G2 of the body frame 200 . Therefore, when welding is performed on the abutting portion between the end frame 300 and the body frame 200, as shown at A6 in FIG. 8, the end frame 300 is supported by the body frame 200, so the welding process can be performed more smoothly. In addition, according to this configuration, the end frame 300 is supported by the body frame 200, so that the mechanical coupling force between the end frame 300 and the body frame 200 can be further improved. In addition, according to the embodiment, the main body frame 200 may be present at the lower portion of at least some welded portions, such as the portion indicated by A6. Accordingly, sealing performance of the welded portion can be further improved. In addition, when the configuration as shown in FIG. 8 is provided together at mutually opposing corners of the body frame 200, for example, the upper side corner and the lower side corner, the end frame 300 and the body frame 200. A fitting coupling configuration is implemented, and the fixation between them can be further improved.

Meanwhile, even in the implementation configuration of FIG. 7 , the implementation configuration shown in FIG. 6 may be employed. For example, in the embodiment of FIG. 7 , parts marked D3-D3' may be configured in the form shown in FIG. 6 .

According to such an embodiment, the end frame 300 is supported in the outer direction (upper direction) by the body frame 200 at the portion indicated by D2-D2', and the end frame 300 is supported in the inner direction (lower direction) by the body frame 200 at the portion indicated by D3-D3'. That is, in this case, the end frame 300 may be supported by the body frame 200 toward both the outer direction (upper direction) and the inner direction (lower direction). Therefore, by combining these two configurations, the end frame 300 can be fitted and coupled by the body frame 200 . Therefore, the bonding force between the end frame 300 and the body frame 200 can be further improved.

The body frame 200 may be configured in the form of a clad metal. This will be described in more detail with reference to FIG. 9 .

9 is a cross-sectional view schematically showing some configurations of the body frame 200 according to another embodiment of the present invention. For example, FIG. 9 may be referred to as another modified example of FIG. 8 .

Referring to FIG. 9 , the body frame 200 may be configured in the form of a clad metal having an inner layer as indicated by L1 and an outer layer as indicated by L2. In the case of such a clad metal, at least two members, that is, the inner layer (L1) and the outer layer (L2) may be configured in a form bonded to each other. In particular, in the case of a clad metal, two members (an inner layer and an outer layer) formed in a plate shape may be configured in a bonded form while being in surface contact with each other. In this case, both the inner layer L1 and the outer layer L2 may be made of a metal material, or one of the inner layer L1 and the outer layer L2 may be made of a metal material. As a manufacturing method of the clad metal, technologies known at the time of filing of the present invention, such as welding, rolling, casting, and extrusion, may be employed.

According to the embodiment in which the body frame 200 is configured in the form of a clad metal as described above, various performances of the body frame 200 can be secured through the characteristics of different materials.

In particular, as in the above embodiment, when the body frame 200 is configured in the form of a clad metal, the inner layer L1 may be made of SUS (Stainless Steel) and the outer layer L2 may be made of aluminum. In this case, the end frame 300 may be formed of an aluminum material. As a more specific example, in the case of the embodiment shown in FIG. 9, it can be said to show a partial cross-sectional configuration of the upper side of the body frame 200, in the case of the outer layer (L2) located on the upper part is made of Al material, In the case of the inner layer (L1) located on the lower part, it may be made of SUS material. At this time, the outer layer L2 of the body frame 200 may be welded to the end frame 300 to form a welded portion, as indicated by A7 in FIG. 9 . Also, the inner layer L1 may be positioned to face the cell assembly 100 .

As in the above embodiment, when the outer layer L2 of the body frame 200 is formed of an aluminum material similarly to the end frame 300, excellent weldability with the end frame 300 can be secured. In addition, when the inner layer L1 of the body frame 200 is formed of SUS material, even if a high-temperature venting gas or flame is ejected from the cell assembly 100, stability against high-temperature venting gas or flame can be secured.

At least a portion of the end frame 300 may be seated on the outer surface of the inner layer L1. And, in the end frame 300, in a state where it is seated on the outer surface of the inner layer (L1) in this way, an end portion of the seated portion may be welded to the outer layer (L2).

For example, as indicated by A8 in FIG. 9 , a portion of the end frame 300, for example, the protrusion P, may be seated on the upper surface of the inner layer L1. In addition, the end of the protrusion P seated on the upper surface of the inner layer L1 may form a welded portion at a portion in contact with the outer layer L2 of the body frame 200, as indicated by A7.

According to this embodiment of the present invention, coupling and weldability between the end frame 300 and the body frame 200 can be secured more excellently. In addition, according to the above embodiment, the gap between the end frame 300 and the body frame 200 is formed to be curved, so that sealing against venting gas or flame can be secured more stably.

10 is a perspective view schematically illustrating the configuration of a battery module according to another embodiment of the present invention.

Referring to FIG. 10 , a venting hole may be formed on at least one side of the body frame 200, as indicated by H1. For example, venting holes H1 may be formed in the left frame and the right frame of the body frame 200 . When the venting gas is generated and ejected from the cell assembly 100 accommodated in the internal space defined by the body frame 200 and the end frame 300, the venting hole H1 may be configured to discharge the generated venting gas from the internal space to the external space.

For example, the venting hole H1 may be formed in a completely open form so as to pass through the body frame 200 in an inward and outward direction. However, the venting hole H1 may not be completely opened, but may be configured in a form that is closed in a normal state and can be opened according to a change in pressure or temperature. In addition, the venting hole H1 may be formed to extend in one direction. For example, as shown in FIG. 10 , the venting hole H1 may be formed to elongate in the vertical direction. In FIG. 10, the venting holes H1 are shown as being formed on the left side (left frame) and the right side (right frame) of the body frame 200, but such a venting hole H1 is the upper surface of the body frame 200 (upper frame) or lower surface (lower frame).

According to this embodiment of the present invention, the pressure inside the battery module is increased by the venting hole (H1), so that the battery module can be prevented from exploding. Also, in this case, it is possible to limit the discharge position of the venting gas.

In this configuration, the battery module according to the present invention may further include a venting unit 400 . The venting unit 400 may be provided outside the body frame 200 . In particular, the venting unit 400 may be attached to a portion of the body frame 200 where the venting hole H1 is formed. For example, as shown in FIG. 10, when the venting holes H1 are formed on the left and right sides of the body frame 200, the venting unit 400 is the left and right sides of the body frame 200. It can be attached to the outside of each.

The venting unit 400 may be configured such that the venting gas discharged from the venting hole H1 is introduced and discharged to the outside. That is, the venting unit 400 may be configured to limit an internal space to function as a venting channel. As a more specific example, the venting unit 400 attached to the left side of the body frame 200 may be configured in a form in which the left, upper, lower and front portions are closed and the right and rear portions are open. At this time, the inner space of the venting unit 400 is limited by the closed left part, upper part, lower part, and front part, and such an inner space may function as a venting channel. In addition, venting gas may flow in and out due to the open right and rear parts. For example, in the case of the left venting unit 400, the venting gas inside the body frame 200 may be introduced into the open right part and the venting gas may be discharged through the open rear part. At this time, the venting hole H1 formed on the left side of the body frame 200 may be formed on the front side of the body frame 200 . In this case, the venting gas discharged from the body frame 200 may flow into the left venting unit 400, flow backward, and then be discharged to the outside.

According to this embodiment of the present invention, the discharge direction of the venting gas can be controlled with a simple structure, and the external discharge of flames or high-temperature particles can be suppressed. In particular, according to the embodiment, when the venting gas is discharged via the venting hole H1 and the venting unit 400, the discharge path is bent at least once, so that flames with strong straightness or discharge of high-temperature particles can be prevented.

11 is a perspective view schematically illustrating the configuration of a battery module according to another embodiment of the present invention. In addition, FIG. 12 is a perspective view schematically showing the configuration of the end frame 300 included in FIG. 11 from another angle.

Referring to FIGS. 11 and 12 , the end frame 300 may include an end plate 310 and a side plate 320 . Here, the end plate 310 may be formed in a plate shape and erected in a vertical direction. In addition, the side plate 320 may be configured to protrude from a corner portion of the end plate 310 toward the body frame 200 .

In particular, as shown in FIGS. 11 and 12 , the end plate 310 may have a substantially square plate shape, and the side plates 320 may be positioned at each corner of the square end plate 310 . That is, the side plate 320 may be located on the upper, lower, left and right sides of the end plate 310 , respectively. Also, the side plate 320 may have a welded portion welded to the body frame 200 at an end thereof. In particular, all four side plates 320 positioned on the upper, lower, left, and right sides of the end frame 300 may have welding lines welded to the body frame 200 .

Furthermore, as shown in FIGS. 11 and 12 , the end frame 300 has four side plates 320, that is, an upper side plate, a lower side plate, a left side plate, and a right side plate. Protrusions P may be formed on all of them. In this configuration, each side plate 320 of the end frame 300 may be provided with a welding part formed in a line shape bent according to the protruding shape of the protruding part P provided at the inner end, that is, a welding line.

According to this embodiment of the present invention, long welding lines may be formed at various corners of the end frame 300, particularly at all corners of the upper side, the lower side, the left side, and the right side. Accordingly, coupling force between the end frame 300 and the body frame 200, sealing property, and the like can be further improved.

As indicated by H2 in FIGS. 11 and 12 , the end frame 300 may have a venting hole formed therein. That is, in the previous embodiment of FIG. 10, the venting hole H1 is formed in the body frame 200, but in this embodiment, the venting hole H2 is formed in the end frame 300 instead of the body frame 200. In particular, the end frame 300 may include an end plate 310 and a side plate 320 , and the venting hole H2 may be formed in the side plate 320 . The venting hole H2 may be formed to pass through the side plate 320 from the inside to the outside.

According to this configuration of the present invention, explosion of the battery module can be prevented by reducing the internal pressure of the battery module by the venting hole H2. In addition, in this case, since the venting hole H2 is positioned at the front or rear end of the battery module, the venting gas inside the battery module can be quickly and smoothly discharged to the outside. In particular, inside the battery module, the cell assemblies 100, as shown in FIG. 2, may be stacked in the left and right directions in a state in which they are erected in the vertical direction. At this time, the venting gas discharged from one or more battery cells 110 included in the cell assembly 100 tends to gather in the front or rear of the battery module, which is a space where electrode leads are located. In this case, as in the above embodiment, the venting gas can be discharged more quickly and smoothly through the venting hole H2 by positioning the venting hole H2 at the front or rear side of the battery module as much as possible.

In particular, according to this configuration, the configuration provided by the protruding portion P can be easily implemented even in the side plate 320 in which the venting hole H2 is formed in the end frame 300 . Therefore, a welded line is formed on each side plate 320 of the end frame 300, particularly all the side plates 320, so that a sufficient welding portion can be provided. Therefore, in this case, rapid and smooth discharge of the venting gas and improvement in bonding force between the end frame 300 and the body frame 200 can be implemented together. In addition, high-temperature venting gas or flame may be concentrated on the side plate 320 in which the venting hole H2 is formed in the end frame 300. In the case of the above embodiment, the side plate 320 in which the venting hole H2 is formed. A welded portion is sufficiently formed, so that the bonding force can be stably maintained.

In the case of the embodiment shown in FIG. 12 , it can be said to represent the front frame 301 among the end frames 300 . In the case of such a front frame 301, a venting hole H2 may be formed in the left plate located in the -X-axis direction. In addition, as shown in FIG. 11 , the end frame 300 may also include a rear frame 302 . Even in the case of the rear frame 302, a venting hole H2 may be formed, and the venting hole H2 of the rear frame 302 may be formed in a right plate of the rear frame 302.

According to this configuration of the present invention, since the venting holes H2 are formed on the left and right sides of the battery module, respectively, venting gas or flame inside the battery module can be discharged more smoothly and quickly. Moreover, in the case of the above embodiment, the venting hole H2 on the left side of the battery module is located at the front, and the venting hole H2 at the right side of the battery module is located at the rear.

According to this embodiment of the present invention, the venting gas discharged from the battery module can be dispersed and discharged to the front and rear. Accordingly, it is possible to prevent a concentration increase in temperature of a specific part outside the battery module.

Even in the configurations of FIGS. 11 and 12 , the battery module according to the present invention may further include a venting unit 400 . Since this venting unit 400 is similar to the venting unit 400 described above in the embodiment of FIG. 10 , the description thereof may be similarly applied. However, in the embodiments of FIGS. 11 and 12 , the venting hole H2 is formed in the end frame 300 . Therefore, it can be said that the venting unit 400 is provided outside the side of the end frame 300 where the venting hole H2 is formed. The fact that the venting unit 400 is configured to move the venting gas discharged from the venting hole H2 is the same as described in the exemplary embodiment of FIG. 10 .

11 and 12, the venting unit 400 may be coupled to the end frame 300 and the body frame 200 together. That is, the venting unit 400 is generally coupled to the body frame 200, but since it is configured to cover up to the venting hole H2 of the end frame 300, it may also be coupled to the end frame 300. For example, the venting unit 400 may be provided on the left and right sides of the battery module, respectively. At this time, the left venting unit 400 may be welded to the left plate of the left frame and the front frame 301 of the body frame 200 . In addition, the right venting unit 400 may be welded to the right frame of the body frame 200 and the right plate of the rear frame 302 .

The venting unit 400 may be made of a metal material to withstand high-temperature venting gas or flame. For example, the venting unit 400 may be made of aluminum or SUS. However, the venting unit 400 may be made of a material other than these materials or may further include another material.

According to the above embodiment of the present invention, the venting gas or flame can be controlled more effectively by the venting unit 400 . In particular, in the case of the above embodiment, the venting direction of the venting gas or flame is limited, and external discharge of flame or spark can be suppressed.

A battery pack according to the present invention may include one or more battery modules according to the present invention described above. In addition, the battery pack according to the present invention, in addition to the battery module, other various components, such as BMS, bus bar, pack case, relay, current sensor, etc., are known at the time of filing of the present invention. It may further include components of the battery pack.

The battery module according to the present invention can be applied to vehicles such as electric vehicles or hybrid vehicles. That is, the vehicle according to the present invention may include the battery module according to the present invention or the battery pack according to the present invention. In addition, the vehicle according to the present invention may further include various other components included in the vehicle in addition to the battery module or the battery pack. For example, a vehicle according to the present invention may further include a control device such as a vehicle body, a motor, and an electronic control unit (ECU), in addition to the battery module according to the present invention.

In addition, the battery module according to the present invention may be applied to an energy storage system (ESS). That is, the energy storage system according to the present invention may include the battery module according to the present invention or the battery pack according to the present invention.

On the other hand, in the present specification, terms indicating directions such as up, down, left, right, front, and back are used, but these terms are only for convenience of description, and may vary depending on the location of a target object or the location of an observer. It is obvious to those skilled in the present invention.

As described above, although the present invention has been described by the limited embodiments and drawings, the present invention is not limited thereto, and various modifications and variations are possible within the scope of equivalents of the technical spirit of the present invention and the claims to be described below by those skilled in the art to which the present invention belongs.

100: cell assembly
110: battery cell
200: body frame
300: end frame
301: front frame, 302: rear frame
310: end plate, 320: side plate
400: venting unit
P: protrusion
G1, G2: Recess
H1, H2: Venting hole

Claims (14)

a cell assembly comprising one or more battery cells;
a body frame configured to accommodate the cell assembly in an inner space and having an open portion formed on at least one side; and
End frame welded to the open portion of the body frame and having welded portions formed at different positions along the coupling direction to the body frame.
A battery module comprising a. According to claim 1,
The battery module, characterized in that the end frame has a front frame and a rear frame, respectively welded to the front and rear of the body frame. According to claim 1,
The battery module, characterized in that the end frame has four corners, and a welded portion is formed at at least one corner of the four corners. According to claim 1,
The battery module, characterized in that the welding portion is configured in the form of a bent line. According to claim 4,
The battery module, characterized in that the welding portion is configured in the form of a line bent, respectively, at at least two corners among a plurality of corners provided on the end frame. According to claim 1,
The end frame has a protrusion formed to protrude in the coupling direction,
The battery module, characterized in that the body frame has a concave portion configured to enable the protrusion to be inserted and fastened. According to claim 1,
The battery module, characterized in that the body frame is configured in the form of a clad metal having an inner layer and an outer layer. According to claim 7,
The inner layer is a SUS material, the outer layer is a battery module, characterized in that aluminum material. According to claim 7,
The battery module according to claim 1 , wherein, in a state in which at least a portion of the end frame is seated on the outer surface of the inner layer, an end portion of the seated portion is welded to the outer layer. According to claim 1,
The battery module according to claim 1 , wherein the end frame includes an end plate and a side plate protruding from a corner portion of the end plate toward the body frame and having the weld portion formed at an end thereof. According to claim 10,
The battery module, characterized in that the end frame, a venting hole is formed in the side plate. According to claim 11,
The battery module of claim 1, further comprising a venting unit provided outside the side surface of the end frame where the venting hole is formed to allow the venting gas discharged from the venting hole to move. A battery pack comprising the battery module according to any one of claims 1 to 12. A vehicle comprising the battery module according to any one of claims 1 to 12.

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