BATTERY MODULE AND BATTERY PACK INCLUDING THE SAME

Discussed is a battery module that may include a battery cell stack including a plurality of battery cells stacked in one direction, a module frame that houses the battery cell stack and has an inner surface and an outer surface, and an end plate coupled to the module frame and configured to cover a front surface or a rear surface of the battery cell stack, wherein a venting part is formed in the module frame, and wherein the venting part comprises a pattern part having a concentric diagram shape and a support part configured to support the pattern part.

CROSS CITATION WITH RELATED APPLICATION(S)

This application claims the benefit of Korean Patent Application No. 10-2021-0023581 filed on Feb. 22, 2021 with the Korean Intellectual Property Office, the content of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module having improved safety and a battery pack including the same.

BACKGROUND ART

Along with the technology development and increased demand for mobile devices, demand for secondary batteries as energy sources has been increasing rapidly. In particular, a secondary battery has attracted considerable attention as an energy source for power-driven devices, such as an electric bicycle, an electric vehicle, and a hybrid electric vehicle, as well as an energy source for mobile devices, such as a mobile phone, a digital camera, a laptop computer and a wearable device.

When the secondary battery is mainly used in devices such as mobile devices, use of one or two to four battery cells has no difficulty in achieving the storage capacity and energy output level required by each device, but medium- or large-sized devices such as automobiles require high-power and large-capacity storage devices and thus, when a small number of battery cells are used as described above, major problems may occur in terms of energy storage capacity and energy output. Therefore, in the medium- or large-sized device, it is common to mount a battery module in which a plurality of battery cells are electrically connected or a battery pack including a plurality of such battery modules.

FIG.1is an exploded perspective view of a conventional battery module.

Referring toFIG.1, the conventional battery module10includes a battery cell stack12in which a plurality of battery cells11are stacked, a module frame20for protecting the battery cell stack12from external impact, heat or vibration, and an end plate40that covers the front surface and/or rear surface of the battery cell stack12.

The battery cell stack12is located in a closed structure by the coupling between the module frame20and the end plate40. In order to maximize the energy storage capacity of the battery module10, each of the battery cells11is mainly located at a narrow interval within the battery cell stack12.

However, such a design of the battery module10is likely to impair the durability or long-term stability of the battery module10. Specifically, when the internal pressure of the battery cell11increases due to overcharging or the like, high-temperature heat, gas, or flame may be discharged to the outside of the battery cell11, wherein heat, gas, or flame discharged from one battery cell11is transferred to another adjacent battery cell11at a narrow interval, which may cause continuous ignition phenomena. Additionally, heat, gas, or flame discharged from each battery cell11may be discharged toward an opening formed in the end plate40. In this process, a busbar (not shown) located between the end plate40and the battery cell11may be damaged.

Moreover, the plurality of battery modules10in the battery pack are arranged such that at least two end plates40face each other. Therefore, when heat, gas, or flame generated within the battery module10is discharged to the outside of the battery module10, it may affect the performance and stability of the plurality of battery cells11in another adjacent battery module10.

Therefore, there is a need to develop the battery module10having improved durability and safety by effectively delaying the heat propagation speed during ignition inside the battery module10and allowing the generated heat, gas or flame to be rapidly discharged to the outside of the battery module10.

DETAILED DESCRIPTION OF THE INVENTION

Technical Problem

It is an object of the present disclosure to provide a battery module that effectively suppresses flames at the time of occurring an ignition inside the battery module and effectively discharges internal heat, gas, or flames, and a battery pack including the same.

The objects of the present disclosure are not limited to the aforementioned objects, and other objects which are not described herein should be clearly understood by those skilled in the art from the following detailed description and the accompanying drawings.

Technical Solution

According to one embodiment of the present disclosure, there is provided a battery module including: a battery cell stack including a plurality of battery cells stacked in one direction, a module frame that houses the battery cell stack and has an inner surface and an outer surface, and an end plate coupled to the module frame and configured to cover a front surface or a rear surface of the battery cell stack, wherein a venting part is formed in the module frame, and wherein the venting part includes a pattern part having a concentric diagram shape and a support part configured to support the pattern part.

The support part may have an X-shape.

The venting part may include at least one of an inlet port formed in the inner surface of the module frame and a venting hole in a form of a hole that defines an outlet port formed on the outer surface of the module frame.

The venting part may include a terminal region including the inlet port of the outlet port of the venting hole, and the terminal region may have a reverse tapered shape.

Based on an axial cross section of the venting hole, a side surface of the venting hole extending between the inlet port and the outlet port has a round shape, and an effluent flowing in through the inlet port may be moved to the outlet port along the round shape of the venting hole.

A blocking sheet may be located at the inlet port of the venting part.

The blocking sheet may include a material that melts in accordance with a temperature inside the module frame.

The blocking sheet may include at least one selected from the group consisting of inorganic carbonate, inorganic phosphate, and inorganic sulfate.

When the one direction in which the plurality of battery cells are stacked is defined as a stacking direction, the venting part may be formed on one surface of the module frame extending along the stacking direction.

When the one direction from the front surface to the rear surface of the battery cell stack is defined as a longitudinal direction, a longitudinal position of the venting part may be closer to the front surface or the rear surface of the battery cell stack than to a central part of the battery cell stack having a same longitudinal distance as the front surface and the rear surface of the battery cell stack.

A battery cell of the plurality of battery cells may include an electrode lead protruding from one end part of the battery cell, and the electrode lead may be located on the front surface or the rear surface of the battery cell stack.

According to another embodiment of the present disclosure, there is provided a battery pack including at least one battery module described above.

Advantageous Effects

According to embodiments, the venting part is formed in the module frame, whereby it is possible to effectively suppress flames at the time of occurring an ignition inside the battery module and effectively discharges internal heat.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Portions that are irrelevant to the description will be omitted to clearly describe the present disclosure, and same reference numerals designate same or like elements throughout the description.

Further, in the drawings, the size and thickness of each element are arbitrarily enlarged or reduced illustrated for convenience of description, and the present disclosure is not necessarily limited to those illustrated in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for clarity. In the drawings, for convenience of description, the thicknesses of some layers and regions are exaggerated.

In addition, it will be understood that when an element such as a layer, film, region, or plate is referred to as being “on” or “above” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, it means that other intervening elements are not present. Further, the word “on” or “above” means disposed on or below a reference portion, and does not necessarily mean being disposed on the upper end of the reference portion toward the opposite direction of gravity. Meanwhile, similar to the case where it is described as being located “on” or “above” another part, the case where it is described as being located “below” or “under” another part will also be understood with reference to the above-mentioned contents.

Further, throughout the description, when a portion is referred to as “including” or “comprising” a certain component, it means that the portion can further include other components, without excluding the other components, unless otherwise stated.

Further, throughout the description, when referred to as “planar”, it means when a target portion is viewed from the upper side, and when referred to as “cross-sectional”, it means when a target portion is viewed from the side of a cross section cut vertically.

Hereinafter, a battery module according to an embodiment of the present disclosure will be described.

FIG.2is a perspective view of a battery module according to an embodiment of the present disclosure.FIG.3is an exploded perspective view of the battery module ofFIG.2.FIG.4is a diagram showing a battery cell included in the battery module ofFIG.2.

Referring toFIGS.2and3, the battery module100according to an embodiment of the present disclosure may include a battery cell stack120in which a plurality of battery cells110are stacked in one direction, a module frame200that houses the battery cell stack120, busbar frames300that are located on the front surface and/or rear surface of the battery cell stack120, end plates400that cover the front surface and/or rear surface of the battery cell stack120, and busbars510and520that are mounted on the busbar frame300.

The battery cells110may be provided in a pouch shape that can maximize the number of cells stacked per unit area. The battery cell110provided in the pouch shape can be manufactured by housing an electrode assembly including a positive electrode, a negative electrode, and a separator in a cell case114of a laminate sheet and then heat-sealing the sealing part of the cell case114. However, it will be obvious that the battery cell110need not be essentially provided in a pouch shape, and can be provided in a square, cylindrical, or various other forms, at a level where the storage capacity required by the device to be mounted in the future is achieved.

Referring toFIG.4, the battery cell110may include two electrode leads111and112. The electrode leads111and112may have a structure protruding from one end of the cell main body113, respectively. Specifically, one end of respective electrode leads111and112is located inside the battery cell110and thus is electrically connected to the positive electrode or negative electrode of the electrode assembly. The other end of the respective electrode leads111and112is protruded to the outside of the battery cell110, and thus can be electrically connected with a separate member, for example, the busbars510and520.

The electrode assembly in the cell case114can be sealed by the sealing parts114sa,114sband114sc. The sealing parts114sa,114sband114scof the cell case114may be located on both end parts114aand114band one side part114cconnecting them.

The cell case114is generally formed of a laminate structure of a resin layer/metallic thin film layer/resin layer. For example, when a surface of the cell case is formed of an O (oriented)-nylon layer, it tends to slide easily by an external impact when a plurality of battery cells110are stacked to form a medium- or large-sized battery module100. Therefore, in order to prevent this sliding and maintain a stable stacking structure of the battery cells110, an adhesive member, for example, a sticky adhesive such as a double-sided tape or a chemical adhesive coupled by a chemical reaction upon adhesion, can be adhered to the surface of the battery case114to form a battery cell stack120.

The connection part115may refer to a region extending along the longitudinal direction at one end of the cell case114in which the above-mentioned sealing parts114sa,114sband114scare not located. A protrusion part110pof the battery cell110called a bat-ear may be formed at an end part of the connection part115. Further, the terrace part116may refer to a region between electrode leads111and112in which a part protrudes to the outside of the cell case114, and the cell main body113located inside the cell case114, on the basis of the edge of the cell case114.

Meanwhile, the battery cell110provided in the pouch type may have a length, a width and a thickness, and the longitudinal direction, the width direction, and the thickness direction of the battery cell110may be a direction perpendicular to each other.

Here, the longitudinal direction of the battery cell110may be defined according to the direction in which the electrode leads111and112protrude from a cell case114. For example, one electrode lead111protrudes in one direction (x-axis direction) from one end part114aof the cell case114, and the other electrode lead112may protrude from one end part114bof the cell case114in a direction opposite to the above-mentioned one direction (−x axis direction). At this time, the longitudinal direction of the battery cell110may be defined as an x-axis direction or a −x-axis direction.

Also, the width direction of the battery cell110herein may be a z-axis direction or a −z-axis direction from one side part114cof battery cell110to a connection part115or from the connection part115to the one side part114cof the battery cell110as shown inFIG.4. Further, the thickness direction of the battery cell110herein may be defined as a y-axis direction or a −y-axis direction perpendicular to the width direction and the length direction.

Meanwhile, the longitudinal direction, the width direction, and the thickness direction have been described above on the basis of the axis direction shown through the drawings, but this is only for convenience of explanation and thus, the thickness direction, length direction, and width direction described above can be defined differently from the drawings shown in accordance with the structure of the battery cell110.

The battery cell stack120may be one in which a plurality of electrically connected battery cells110are stacked along one direction. A direction in which the plurality of battery cells110are stacked (hereinafter referred to as a ‘stacking direction’) may be a y-axis direction as shown inFIGS.2and3(or it may be a −y-axis direction, and in the following, the expression ‘axial direction’ may be interpreted as including all +/−directions).

Here, the stacking direction of the battery cell stack120may be the thickness direction of the battery cell110. This may be because the thickness of the battery cell110is designed so as to have a value smaller than the length and width of the battery cell110, and its volume can be minimized when stacked along the above-mentioned direction. Therefore, it will not be interpreted that the stacking direction of the battery cell stack120and the thickness direction of the battery cell110are always the same, and the stacking direction thereof can be determined in accordance with the shape of the battery cell110.

The battery cell stack120can have a shape similar to that of a rectangular parallelepiped as a whole. Each surface of the battery cell stack120can be defined by the stacking direction (y-axis direction).

For example, two surfaces facing each other in the stacking direction among one surface of the battery cell stack120may be defined as side surfaces of the battery cell stack120. One surface of one battery cell110having a length and a width may be located on a side surface of the battery cell stack120.

Further, among one surface of the battery cell stack120, a surface facing each other on the axis perpendicular to the stacking direction may be defined as a front surface/a rear surface or an upper surface/a lower surface. The front surface, rear surface, upper surface or lower surface of the battery cell stack120may be a surface extending along the stacking direction of the battery cell stack120. One surface of a plurality of battery cells110may be located side by side on the front surface, rear surface, upper surface and lower surface of the battery cell stack120. Here, one surface of the battery cells110positioned side by side may be a surface parallel to the thickness direction.

A direction in which the battery cell stack120heads from the front surface to the rear surface, or a backward direction thereof may be defined as the longitudinal direction of the battery cell stack120, which may be an x-axis direction. Further, a direction in which the battery cell stack120heads from the upper surface to the lower surface, or a backward direction thereof may be defined as the width direction of the battery cell stack120, which may be a z-axis direction.

The longitudinal direction of the battery cell stack120may be substantially the same as the longitudinal direction of the battery cells110. The electrode leads111and112of the battery cells110may be located on the front surface and rear surface of the battery cell stack120. As shown inFIG.3, when the electrode leads111and112of each battery cell110are arranged to be concentrated on the front surface and rear surface of the battery cell stack120, the busbars510and520of the battery module100may be designed so as to be located close to the front surface and rear surface of the battery cell stack120. Thereby, the busbars510and520may more easily provide an electrical connection between the electrode leads111and112located inside the battery module100and an electrical member located outside the battery module100.

The battery cell stack120may include a peripheral region120aand a central region120bthat are defined according to the positions in the longitudinal direction. Specifically, the battery cell stack120may include a central region120bincluding a central surface (or a central part) spaced apart by the same distance from the front and rear surfaces of the battery cell stack120, and a peripheral region120aspaced apart from the central region. Here, the peripheral region120amay be located closer to the busbar frame300, the end plate400, and the busbars510and520, which will be described later, than the central region120b.Further, here, the peripheral region120amay include a region in which the electrode leads111and112are located, but this is not always the case.

The module frame200may be for protecting the battery cell stack120and the electrical components connected thereto from external physical impacts. The module frame200may be house the battery cell stack120and the electric device connected thereto in the internal space of module frame200. Here, the module frame200includes an inner surface200a(seeFIG.5) and an outer surface200b(seeFIG.5), and the inner space of the module frame200may be defined by the inner surface200a.

The structure of the module frame200may be various. In one example, the structure of the module frame200can be the structure of a mono frame. Here, the mono frame may be in a metal plate shape in which the upper surface, the lower surface and both side surfaces are integrated. The mono frame can be manufactured by extrusion molding. In another example, the structure of the module frame200may be a structure in which a U-shaped frame and an upper plate are combined. In the case of a structure in which the U-shaped frame and the upper plate are combined, the structure of the module frame200may be formed by coupling the upper plate to the upper side surfaces of the U-shaped frame, which is a metal plate in which the lower surface and both sides are combined or integrated. Each frame or plate can be manufactured by press molding. Further, the structure of the module frame200can be provided in the structure of an L-shaped frame in addition to the mono frame or the U-shaped frame, and may be provided in various structures that are not described in the above-mentioned examples.

The structure of the module frame200may be provided in a shape that is opened along the longitudinal direction of the battery cell stack120. The front surface and rear surface of the battery cell stack120may not be covered by the module frame200. The electrode leads111and112of the battery cells110may not be covered by the module frame200. The front surface and rear surface of the battery cell stack120may be covered by the busbar frame300, the end plate400, the busbars510and520, or the like, which will be described later. Thereby, the front surface and rear surface of the battery cell stack120can be protected from external physical impacts and the like.

Meanwhile, a compression pad150may be located between the battery cell stack120and one side surface of the inner surface of the module frame200. At this time, the compression pad150may be located on the y-axis of the battery cell stack120, and may face at least one surface of the two battery cells110at both ends of the battery cell stack120.

Further, although not shown in the figure, a thermal conductive resin may be injected between the battery cell stack120and the lower surface of the module frame200, and a thermal conductive resin layer (not shown) may be formed between the battery cell stack120and the lower surface of the module frame200through the injected thermal conductive resin. At this time, the thermal conductive resin layer may be located on the z-axis of the battery cell stack120, and the thermal conductive resin layer may be formed between the battery cell stack120and the bottom surface (or may be referred to as a bottom part) located on the −z axis of the module frame200.

The busbar frame300can be located on one surface of the battery cell stack120to cover one surface of the battery cell stack120and, at the same time, guide the connection between the battery cell stack120and an external device. The busbar frame300may be located on the front surface or rear surface of the battery cell stack120. At least one of the busbars510and520and the module connector may be mounted on the busbar frame300. As a specific example, referring toFIGS.2and3, one surface of the busbar frame300is connected with the front surface or rear surface of the battery cell stack120, and the other surface of the busbar frame300may be connected with the busbars510and520.

The busbar frame300may include an electrically insulating material. The busbar frame300can restrict the busbars510and520from making contact with other parts of the battery cells110, except the parts where they are joined to the electrode leads111and112, and can prevent the occurrence of an electrical short circuit.

Although not shown in the figure, the busbar frame300may be formed in two numbers, and may include a first busbar frame located on the front surface of the battery cell stack120and a second busbar frame located on the rear surface of the battery cell stack120.

The end plate400can be for protecting the battery cell stack120and electrical equipment connected thereto from external physical impacts by sealing the opened surface of the module frame200. For this purpose, the end plate400may be made of a material having a predetermined strength. For example, the end plate400may include a metal such as aluminum.

The end plate400may be coupled (joined, sealed or closed) to the module frame200while covering the busbar frame300or the busbars510and520located on one surface of the battery cell stack120. Each edge of the end plate400may be coupled to a corresponding edge of the module frame200by a method such as welding. Further, an insulating cover800for electrical insulation may be located between the end plate400and the busbar frame300.

Although not shown in the figure, the end plate400may be formed in two numbers, and may include a first end plate located on the front surface of the battery cell stack120and a second end plate located on the rear surface of the battery cell stack120.

The first end plate can be joined to the module frame200while covering the first busbar frame on the front surface of the battery cell stack120, and the second end plate can be joined to the module frame200while covering the second busbar frame. In other words, a first busbar frame may be located between the first end plate and the battery cell stack120, and a second busbar frame may be located between the second end plate and the rear surface of the battery cell stack120.

The busbars510and520may be mounted on one surface of the busbar frame300, and may be for electrically connecting the battery cell stack120or the battery cells110and an external device circuit. The busbars510and520are located on the battery cell stack120or the busbar frame300and the end plate400, whereby they can be protected from external impacts and the like, and deterioration of durability can be minimized due to external moisture and the like.

The busbars510and520can be electrically connected to the battery cell stack120through the electrode leads111and112of the battery cells110. Specifically, the electrode leads111and112of the battery cells110pass through a slit formed in the busbar frame300and then are bent to be connected to the busbars510and520. The battery cells110constituting the battery cell stack120may be connected in series or in parallel by the busbars510and520.

The busbars510and520may include a terminal busbar520for electrically connecting one battery module100to another battery module100. At least a part of the terminal busbar520may be exposed to the outside of the end plate400in order to be connected with another external battery module100, and the end plate400may be provided with a terminal busbar opening400H for this purpose.

The terminal busbar520may further include a protrusion part that is protruded upward, unlike other busbars510, and the protrusion part may be exposed to the outside of the battery module100via a terminal busbar opening400H. The terminal busbar520may be connected with another battery module100or a BDU (Battery Disconnect Unit) via a protrusion part exposed through the terminal busbar opening400H, and may form a high voltage (HV) connection with them.

Meanwhile, as described above, an ignition phenomenon may occur inside the battery module100in which the battery cells110are stacked at a high density. When an ignition phenomenon occurs in one battery module100, heat, gas, flame or the like of the battery module100are transferred to the battery module100adjacent thereto, thereby occurring continuous ignition phenomena between the battery modules100. Therefore, there is a problem that the durability and stability of the battery module100or a battery pack including the same is reduced.

Therefore, in the following, a venting part210capable of solving the above ignition phenomena and thus improving the durability and stability of the battery module100will be described.

FIG.5is a cross-sectional view of the battery module ofFIG.2taken along the line A-A.FIG.6is a diagram showing a direction in which heat, gas, flame or the like generated in the internal space of the battery module according to an embodiment of the present disclosure is discharged through the venting part.FIG.7is a diagram showing an example of a venting part of a battery module according to an embodiment of the present disclosure.

Referring toFIGS.5and6, the module frame200according to an embodiment of the present disclosure may include a venting part210penetrating the inner surface200aand the outer surface200bof the module frame200.

The venting part210may be for communicating the inside of the battery module100sealed by the module frame200, the end plate400or the like with the outside of the battery module100. The venting part210may be for discharging heat, gas, flame or the like generated at the time of occurring an ignition inside the battery module100to the outside of the battery module100.

Meanwhile, when the module frame200is provided with a venting part210for communicating the inside and the outside, dust, impurities, etc. outside the module frame200may enter the inside of the module frame200through the hole structure of the venting part210. Therefore, in order to prevent foreign matter from flowing in through the hole of the venting part210, it may be preferable to reduce the size of the hole of the venting part210.

Therefore, the venting part210according to an embodiment of the present disclosure may be designed to include a plurality of holes with small size. Here, the hole of the venting part210may be referred to as a venting hole211, and the size of the venting hole211can be determined by a pattern part212included in the venting part210and a support part214for supporting the same. At this time, the pattern part212may be interpreted as including the support part214, but for convenience of explanation, it will be described separately below.

The venting part210may include a venting hole211that communicates with an inlet port210aformed on the inner surface200aof the module frame200and an outlet port210bformed on the outer surface200b.The hole-inlet port211aof the venting hole211may be located in the inlet port210aof the venting part210, and a hole-outlet port211bof the venting hole211may be located at the outlet port210bof the venting part210. The hole inlet port211a,the hole-outlet port211b,and the hole-side surface211cextending between the hole-inlet port211aand the hole-outlet211bmay be defined by the venting hole211.

The venting part210may include a pattern part212having a concentric diagram pattern shape and a support part214for supporting the shape of the pattern part212. Based on the radial cross-section of the venting part210, the pattern part212may include a plurality of diagrams whose centers coincide with each other and enter and which are radially spaced apart from each other. Additionally, based on the radial cross-section of the venting part210, the support part214may be provided in the form of a bar, and may support a plurality of diagrams included in the pattern part212. The diagrams of the pattern part212may be connected to each other by the support part214, and the entire pattern shape of the pattern part212may be maintained through the support part214.

The shape, size, position, or number of the venting holes211may be defined by the pattern shape of the pattern part212and the shape of the support part214that crosses the pattern part212.

Since the overall shape of the venting hole211may be mainly determined in accordance with the shape of the pattern part212. When describing the shape of the venting hole211, the support part214will be omitted in the following, and the shape of the venting hole211defined by the pattern part212will be mainly described.

The shape of the venting hole211may be a tube shape or a part of the tube shape, wherein the hole-side surface211cof the venting hole211corresponding to the tubular circumferential surface may be mainly defined by the wall surface (or referred to as the side surface)212cof the pattern part212.

Meanwhile, the venting hole211may have a tube shape as shown inFIG.6(a), but may have a deformed tube shape as shown inFIGS.6(b) and6(c). Here, the deformed tube shape may mean that at least a part of the circumferential surface is deformed in a convex or concave shape in the radial direction because the size and shape of the radial cross section are not constant. In a conventional tube shape, the axial cross-section may have an angular shape, but in a deformed tube shape, the axial cross-section may have a round shape.

In a specific example, the venting hole211may have a shape whose radial cross-section (or diameter) increases toward the terminal end in the axial direction, like a bottleneck of a gourd bottle. As shown inFIGS.6(b) and6(c), the terminal region of the venting hole211may have a radially outwardly unfolded shape. A terminal region of the venting hole211may have a reverse tapered shape Here, the terminal region of the venting hole211may refer to a region located at the end part of the shaft of the venting hole211, and the central region of the venting hole211may refer to a region located between the two terminal regions described above.

The reverse tapered shape of the venting hole211may be formed by bending a part of the wall surface212cof the pattern part212. At this time, in the axial cross-section of the venting part210, the wall surface212cof the pattern part212may have a round shape. In the venting part210provided is the upper surface212b,and the edge part212ca corresponding to the reverse tapered shape may also have a round shape. Here, the edge part212ca may mean a part between the lower surface212a(or referred to as the inflow surface) of the pattern portion212located at the inlet port210aand the wall surface212cof the pattern part212.

When the two terminal regions of the venting hole211have a reverse tapered shape, the internal gas of the battery module100may be rapidly moved to the outside of the battery module100through the venting holes211. Specifically, the central region located between the two terminal regions may have a smaller volume per unit length axial than the relatively terminal region. The gas or the like may enter the central region via one terminal region close to the hole-inlet port211a.As the volume decreases, the pressure can increase, and allow quick movement to the other terminal region close to the hole-outlet port211b,which is a relatively low pressure environment. Through this, the gas inside the battery module100can be rapidly discharged to the outside.

Further, in the above-mentioned drawings, both terminal regions of the venting hole211were shown to have a reverse tapered shape, but only one of the two terminal regions of the venting hole211may have a reverse tapered shape. Even if only one of the two terminal regions of the venting hole211has a reverse tapered shape, it can promote the outflow of gas rather than a conventional tube shape, so that the gas discharge effect of the venting hole211provided as shown inFIGS.6(b) and6(c)can be larger than that of the venting hole211provided as shown in FIG. (a).

Meanwhile, as shown inFIG.6(a), when the edge part212cahas an angled shape whereby the venting hole211is provided into a tube shape as the edge part212ca, the internal gas may collide with the edge part212cain the process of discharging heat, gas, or flame inside the battery module100to the outside, and the collided gas or the like enters the inside of the battery module100again, thus causing a problem of impairing the ventilation function of the venting part210.

Meanwhile, as shown inFIGS.6(b) and6(c), when the edge part212cahas a round shape whereby the venting hole211is provided into a reverse tapered shape, the internal gas or the like that has collided with the edge part212camay be moved toward the hole-outlet port211balong the direction guided by the round shape of the edge part212ca.

In this manner, since the discharge path of gas or the like is formed in accordance with the shape of the edge part212caclose to the inlet port210a,the ventilation effect of the venting part210may vary depending on the angle (hereinafter, referred to as a ‘diffraction angle’) formed by the edge part212cawith the inlet port210abased on the axial cross-section of the venting part210. It can be explained that the diffraction angle ofFIG.6(b)is larger than that ofFIG.6(a), andFIG.6(c)is larger than that ofFIG.6(b), wherein the diffraction angle can be calculated based on a tangent line at one point of the edge part212ca.As the diffraction angle is larger, the ventilation function of the venting part210can be improved, but the ventilation function may also depend on the size of the round shape of the edge part212caand the diameter of the central region of the venting hole211. Therefore, as the diffraction angle is larger, the ventilation function of the venting unit210is not necessarily improved.

The venting part210may be formed on at least one surface of the module frame200. Here, the module frame200may be in a state in which two surfaces disposed to face each other on the x-axis, which is the longitudinal direction of the battery cell stack120, are opened. The module frame200may have two surfaces disposed to face each other on the y-axis axis (hereinafter, referred to as ‘surface on the y-axis’) and two surfaces disposed to face each other on the z-axis axis (hereinafter, referred to as ‘surface on the z-axis’).

Here, the surface on the y-axis of the module frame200may face the side surface of the battery cell stack120. One surface on the y-axis of the module frame200may be a surface extending along the width direction or the length direction of the battery cell stack120. One surface on the y-axis of the module frame200may face one surface of one battery cell110. For convenience of explanation, one surface on the y-axis of the module frame200may be referred to as a side surface of the module frame200.

Further, here, one surface on the z-axis of the module frame200may face the upper surface or the lower surface of the battery cell stack120. One surface on the z-axis of the module frame200may be a surface extending along the stacking direction or the longitudinal direction of the battery cell stack120. One surface on the z-axis of the module frame200may face one surface of each of the plurality of battery cell stacks120arranged side by side in one direction. For convenience of explanation, one surface on the z-axis of the module frame200may also be referred to as an upper surface or a lower surface (bottom surface or bottom part).

As shown inFIGS.5and6, the venting part210may be preferably formed on one surface on the z-axis of the module frame200. This may be because when the venting unit210is located on one surface on the z-axis of the module frame200, the inlet port210aof the venting part210may be located closer to the plurality of battery cells110of the battery cell stack120than when located on one surface on the y-axis, so that heat, gas, or flame discharged from the plurality of battery cells110can be rapidly discharged to the outside. In this manner, the position of the venting part210on the module frame200may be determined depending on the position of one surface of the battery cell stack120in which one surface of the plurality of battery cells110are arranged side by side.

Meanwhile, the position of the venting part210on the module frame200can be determined according to the arrangement of the battery module100in the battery pack. For example, the plurality of battery modules100may be arranged along the y-axis or the x-axis in the battery pack, and may not be arranged in the z-axis direction. At this time, as shown inFIGS.5and6, when the venting part210is formed on one surface on the z-axis of the module frame200, other adjacent battery modules100are not located on the discharge path extending from the inlet port210ato to the outlet port210bof the venting part210, thereby being able to minimize the influence of the discharged heat, gas, or flame on other battery modules100. Meanwhile, when the −z-axis surface among the two surfaces on the z-axis is the mounting surface (or the bottom surface) connected to the battery pack, the venting part210may be formed on the +z axis.

The venting part210may be formed entirely on one surface of the module frame200, or may be formed on a part of one surface of the module frame200. Here, when the venting part210is formed on a part of one surface of the module frame200, the venting part210may be preferably located at the peripheral part of the module frame200. Specifically, when a high-temperature gas or flame is generated from the battery cell110, the high-temperature gas or flame may be transmitted to the adjacent battery module100through the terminal busbar opening400H or the like so that the performance of the adjacent battery module100can be deteriorated. Further, if the flame is discharged directly, the flame is also transmitted to the adjacent battery module, which may cause chain ignitions and explosions. Therefore, when the venting part210is formed in the peripheral part of the module frame200close to the busbar frame300, the end plate400and the busbars510and520, the ignition phenomenon in the battery module100can be resolved through the venting part210, so that the influence of heat, gas, or flame on other battery modules100can be minimized. Additionally, the venting part210may be provided at a position in the longitudinal direction corresponding to the peripheral regions of the electrode leads111and112included in the battery cell stack120. In this case, heat, gas, or flame generated in the peripheral area of the electrode leads111and112may be more effectively discharged through the venting part210. Here, the peripheral region of the electrode leads111and112may refer to a region including the electrode leads111and112and spaced apart from the electrode leads111and112by a predetermined distance or less.

At this time, the peripheral part of the module frame200refers to a part corresponding to the peripheral region120aof the battery cell stack120among the module frame200based on the battery module100coupled to the completed body. Here, the peripheral region120aof the battery cell stack120may include the peripheral regions of the electrode leads111and112, but this is not necessarily the case. Further, the central part of the module frame200herein may refer to a part corresponding to the central region120bof the battery cell stack120in the module frame200.

Meanwhile, inFIGS.2to6described above, it is shown that the number of venting part210is one, but this is not always the case, and the number of venting part210can vary. As an example, the number of venting parts210may be two, and the venting part210may be positioned so as to face each other at both ends in the longitudinal direction of the module frame200. At this time, the venting part210may be provided at a position corresponding to the peripheral region120aof the battery cell stack120. In another example, the number of venting parts210may be two or more, may be arranged in rows or columns. The venting parts210arranged in rows or columns may be disposed at a distance, and in order to effectively discharge the gas inside the battery module100, it may be preferable that the intervals between the respective venting parts210are equal.

At this time, the direction in which the plurality of rows are arranged may be along the longitudinal direction (x-axis direction) of the battery cell stack120. Further, the direction in which the plurality of rows are arranged may be along a direction (y-axis direction or z-axis direction) perpendicular to the longitudinal direction of the battery cell stack120.

The shape of the venting part210may be provided in various ways. InFIGS.2to6described above, it is shown that the pattern portion212of the venting portion210has a concentric circles pattern shape, and the support part214has an x-shaped bar shape. However, similarly toFIG.7(a) showing an example of the venting part210provided in the B region, not only the support portion214is provided as an x-shaped bar composed of at least two bars, but also is able to provide a straight bar made of one bar as shown inFIG.7(b). The straight bar has the advantage that the venting hole211can be formed large, but may have a disadvantage that it is difficult to firmly support the pattern part212. In addition, not only the pattern part212has a concentric pattern shape as shown inFIGS.7(a) and7(b), but also it will also be possible to have a concentric diagram pattern shape whose centers coincide with each other as shown inFIG.7(b). The diagram pattern of the venting part210may be provided differently from the above, and its shape will not be limited by the illustrated drawings.

Meanwhile, the discharge direction in which the gas inside the battery module100is discharged to the outside through the venting part210may be a direction from the hole-inlet port211ato the hole-outlet port211b.By changing the positions of the hole-inlet port211aand the hole-outlet port211bof the venting hole211, the direction of heat, gas, or flame discharged from the venting part210can be adjusted.

When the hole-inlet port211aand the hole-outlet port211bon the z-axis are formed at different positions in the longitudinal direction (x-axis direction) or in the stacking direction (y-axis direction), the discharge direction may form an angle with the direction from the battery cell stack120toward the hole-inlet port211a.Thereby, the directions of the high-temperature heat, gas, and flame flown in from the battery cell stack120can be switched, and the length of the discharge path can be increased, so that the gas or the like discharged through the hole-outlet port211bmay have a lower temperature.

Further, the hole-inlet port211aand the hole-outlet port211bis formed so that the discharge direction of the venting part210forms an angle with the direction in which one surface of the module frame200in which the venting part210is formed is located, which may be for minimizing the influence on the adjacent battery module100in the battery pack. Specifically, the plurality of battery modules100may be arranged along the x-axis direction in the battery pack, wherein the venting part210may be formed on one surface of the module frame200located on the x-axis for various reasons such as design. When the venting part210is positioned on the x-axis, it is easy to affect other adjacent battery modules100. Therefore, it may be desirable to make the discharge path of the venting part210form an angle with the x-axis, more specifically, such that the discharge path of the venting part210is formed in a direction in which the adjacent battery module100is not located.

Here, it is preferable that the heat, gas, or flame discharged from the venting part210diffuse more rapidly to the outside of the battery module100. Therefore, the size of the hole-outlet port211bmay be larger than that of the hole-inlet port211a.

FIG.8is a view showing that the blocking sheet is provided in the venting part of the battery module according to an embodiment of the present disclosure.

Referring toFIG.8, a blocking sheet220for covering the hole of the venting part210may be arranged at a part corresponding to the inlet port210aof the venting part210. The blocking sheet220can prevent foreign matter from flowing in from the outside through the venting hole211.

Additionally, the blocking sheet220may include a material for alleviating the ignition phenomenon at the time of occurring an ignition inside the battery module100. Here, the blocking sheet220may be provided with a material that melts at a specific temperature or pressure or higher. When an ignition occurs inside the battery module100, the blocking sheet220may open the venting hole211, heat, gas, flame and the like may be discharged through the venting hole211.

For example, the blocking sheet220may be provided as a PF film. In another example, the blocking sheet220may include a fire extinguishing agent that can suppress a combustion reaction by releasing carbon dioxide gas. When the blocking sheet220contains a fire extinguishing agent, the battery module100may have a self-extinguishing function. Specifically, when an ignition occurs in the battery module100, the fire extinguishing agent can reduce the influence of heat, gas or flame inside the battery module100, whereby continuous ignition phenomena within the battery module100or between the battery modules100can be prevented or delayed. The blocking sheet220may include one or more fire extinguishing agents selected from the group consisting of inorganic carbonate, inorganic phosphate, and inorganic sulfate. However, the fire extinguishing agent included in the blocking sheet220of the present disclosure is not limited to the above-described examples.

On the other hand, the above-mentioned battery module100may be included in the battery pack. The battery pack includes one or more battery modules according to the present embodiment, and may have a structure that is packed together with a battery management system (BMS) and a cooling device that control and manage battery's temperature, voltage, etc.

Within the battery pack, the battery modules100may be arranged in rows and columns. For example, the battery module100may be disposed so as to face the end plate400with another battery module100. When referring to the position of the end plate400of the above drawing, at least two battery modules100may be understood to be disposed along the longitudinal direction (x-axis direction). In another example, the battery module100may be arranged along a y-axis or a z-axis in addition to a different x-axis. The direction in which the battery modules100are stacked in the battery pack may differ depending on the volume and shape of the battery pack or the internal structure of the device on which the battery pack is mounted. Thus, the stacking direction of the battery module100may be different from the above-described example.

At this time, in order to prevent continuous ignition phenomena between the battery modules100in the battery pack, the position of the venting part210and the discharge direction of the venting part210can be determined. Specifically, the position and discharge direction of the venting part210included in one battery module100may be designed in a direction not to face another adjacent battery module100. More detailed information related thereto may be described with reference to the above description.

The battery module and the battery pack including the same can be applied to various devices. Such a device may be applied to a vehicle means such as an electric bicycle, an electric vehicle, or a hybrid vehicle, but the present disclosure is not limited thereto, and is applicable to various devices that can use a battery module and a battery pack including the same, which also falls under the scope of the present disclosure.

Although the preferred embodiments of the present disclosure has been shown and described above, the scope of the present disclosure is not limited thereto, and numerous changes and modifications can be devised by those skilled in the art using the principles of the invention defined in the appended claims, which also falls within the spirit and scope of the present disclosure.

DESCRIPTION OF REFERENCE NUMERALS