Battery module and battery pack including same

Abstract

The present invention provides a battery module and a battery pack including same, the battery module comprising: a cell assembly including a plurality of battery cells; a body frame having a predetermined length and width, accommodating the cell assembly therein, and having an opening formed on at least one of two sides thereof in the longitudinal direction; and an end frame which is coupled to the opening of the body frame, and which has an open area so that a terminal and a connector are partially exposed to the outside.

Description

Battery module and battery pack including the same

[0001] The present invention relates to a battery module and a battery pack including the same. Specifically, the invention relates to a battery module and a battery pack including the same for preventing thermal runaway from spreading to an adjacent battery module by preventing flames from being ejected near a terminal or connector, which is an open area, during thermal runaway of a pouch cell within the battery module.

[0002]

[0003] As the demand for portable electronic products such as smartphones, laptops, and wearable devices increases rapidly, and the commercialization of robots and electric vehicles begins in earnest, research on high-performance secondary batteries capable of repeated charging and discharging is actively underway.

[0004] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries.

[0005] Among these, lithium-ion batteries are gaining attention for their advantages, such as the ability to freely charge and discharge with almost no memory effect compared to nickel-based batteries, a very low self-discharge rate, and high energy density.

[0006] These lithium secondary batteries often primarily use lithium-based oxides and carbon materials as the positive and negative active materials, respectively.

[0007] A lithium secondary battery comprises an electrode assembly in which a positive plate and a negative plate, each coated with a positive active material and a negative active material respectively, are arranged with a separator in between, and an outer casing, i.e., a battery case, that seals and houses the electrode assembly together with an electrolyte.

[0008] Generally, lithium secondary batteries can be classified according to the shape of the casing into can-type secondary batteries, in which the electrode assembly is embedded in a metal can, and pouch-type secondary batteries, in which the electrode assembly is embedded in a pouch of aluminum laminate sheet.

[0009] Recently, secondary batteries are widely used for driving or energy storage not only in small devices such as portable electronic devices, but also in medium and large devices such as electric vehicles and Energy Storage Systems (ESS).

[0010] A number of these secondary batteries (battery cells) can be electrically connected and housed together inside a module case to form a single battery module.

[0011]

[0012] FIG. 1 is a diagram showing battery modules arranged in series and parallel within a general battery pack, and FIG. 2 is a diagram showing a battery module according to the prior art.

[0013] A plurality of battery modules (10) can be connected in series and parallel as shown in FIG. 1 to form a single battery pack (1).

[0014] However, when multiple battery modules (10) are included inside the battery pack (1) as described above, the battery modules (10) may be vulnerable to thermal chain reactions.

[0015] For example, if an event such as thermal runaway occurs within one battery module (10), it is necessary to prevent such thermal runaway from transitioning to another battery module (10).

[0016] If thermal runaway transfer between battery modules (10) is not suppressed, an event occurring in a specific battery module (10) may cause a chain reaction of multiple battery modules (10), potentially leading to an explosion or fire.

[0017] In particular, if an event such as thermal runaway occurs in any one of the battery modules (10), flames, etc. may be ejected to the outside.

[0018] At this time, if the flame ejection is not properly controlled, the flame may be ejected toward another battery module (10), and there is a high possibility that it will cause a thermal chain reaction in another battery module (10).

[0019] In the case of the battery module (10), as shown in FIG. 2, the upper, lower, left, and right sides are enclosed by the main body frame (11) and the front and rear sides are enclosed by the end frame (12), with the cell assembly housed inside.

[0020]

[0021] Figure 3 is a diagram showing the state in which flames are ejected near the terminal, which is an open area during thermal runaway of a pouch cell in a battery module according to the prior art.

[0022] In the case of a conventional battery module (10), as shown in FIG. 3, when thermal runaway or the like occurs inside, it is very likely that the flame (20) or the like cannot be completely blocked and the flame (20) or the like is exposed to the outside.

[0023] In particular, in a typical battery module, terminals (13) for supplying and charging electric energy or connectors (14) for sensing voltage or temperature are often provided in a form that is exposed to the outside.

[0024] However, in order for the terminal (13) or connector (14) to be exposed to the outside, a hole must be formed in the end frame (12), and due to tolerance, a gap is formed between the hole and the terminal (13) or connector (14), so there is a risk that flame (20) or sparks may be ejected to the outside.

[0025] Furthermore, the area around the terminal (13) or connector (14) may be wrapped with an electrically insulating injection molded material to ensure insulation distance from other parts or watertightness.

[0026] However, in situations such as thermal runaway, there is a high risk that flames (20) will be ejected toward the terminal (13) or connector (14), and if exposed to gas and heat, these insulating injection molded materials may melt, leaving the space where the insulating injection molded materials were located as an empty space.

[0027] These empty spaces can become passages through which a large amount of flame (20) is ejected, which can transfer a thermal runaway situation to other battery modules or cause a fire in other external components.

[0028] In addition, such empty spaces can serve as passages for outside air to flow into the interior.

[0029] Therefore, there is a concern that the battery module in question may cause a fire or significantly increase the scale of the fire.

[0030]

[0031] The present invention has been devised to solve various conventional problems as described above, and aims to provide a battery module and a battery pack including the same for preventing thermal runaway from spreading to adjacent battery modules by preventing flames from being ejected into the open area near the terminal or connector during thermal runaway of a pouch cell within the battery module.

[0032]

[0033] To achieve the above objectives, the present invention provides a battery module comprising: a cell assembly including a plurality of battery cells; a main body frame having a predetermined length and width, in which the cell assembly is accommodated internally, and having an opening formed on at least one of the two sides in the longitudinal direction; and an end frame coupled to the opening of the main body frame, having an open area formed such that a terminal and a connector are partially exposed to the outside; wherein a foamed fire-resistant paint is applied to the surface of the end frame adjacent to the terminal and the connector, so that when a flame is ejected near the terminal or connector, which is the open area, during thermal runaway of the battery cell within the main body frame, the fire-resistant paint expands due to heat, and the foamed material blocks the inflow of air into the main body frame and blocks the ejection of the flame outside the main body frame.

[0034] A film forming a mesh shape with a plurality of through holes may be attached to the surface adjacent to the terminal and the connector of the end frame, and a foamed fire-resistant paint may be applied to the film.

[0035] At this time, it is preferable that the through holes be formed at predetermined intervals across the entire surface area of ​​the film.

[0036] In addition, the shape of the through hole may be formed in a circular or polygonal shape.

[0037] In another embodiment, a plurality of straight protrusions may be formed side by side on the surface of the end frame adjacent to the terminal and the connector, and the foamed fire-resistant paint may be applied to the surface of the end frame including the protrusions.

[0038] In another embodiment, a plurality of grooves of a predetermined shape may be formed on the surface of the end frame adjacent to the terminal and the connector, and the foamed fire-resistant paint may be applied to the surface of the end frame including the grooves.

[0039] In another embodiment, a plurality of protrusions of a predetermined shape may be formed on the surface of the end frame adjacent to the terminal and the connector, and the foamed fire-resistant paint may be applied to the surface of the end frame including the protrusions.

[0040] Meanwhile, the battery pack according to the present invention includes the aforementioned battery module.

[0041]

[0042] Specific details of other embodiments are included in "Specific details for carrying out the invention" and the attached "drawings".

[0043] The advantages and / or features of the present invention and the methods for achieving them will become clear by referring to the various embodiments described in detail below together with the accompanying drawings.

[0044] However, it should be understood that the present invention is not limited to the configurations of each embodiment disclosed below, but may be implemented in various different forms, and that each embodiment disclosed in this specification is provided merely to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the present invention, and that the present invention is defined only by the scope of each claim of the claims.

[0045]

[0046] According to the means for solving the aforementioned problem, the present invention has the following effects.

[0047] The present invention has the effect of preventing air from entering the main body frame and preventing flames from escaping outside the main body frame by applying a foamed fire-resistant paint to surfaces adjacent to the terminals and connectors of the end frame, such that when flames are ejected near the terminals or connectors, which are open areas during thermal runaway of the battery cells within the main body frame of the battery module, the foamed fire-resistant paint expands due to heat, thereby blocking the flames from escaping outside the main body frame.

[0048] Accordingly, by producing a heat shielding effect and a combustion delay effect, it is possible to delay the transfer of thermal runaway to adjacent battery modules.

[0049] In addition, the present invention is configured such that a mesh-shaped film is attached to a surface adjacent to the terminal and connector of an end frame, and then a foamed fire-resistant paint is applied over the film, thereby having the effect of maintaining the shape of the char layer created when the fire-resistant paint is exposed to flames.

[0050] In addition, the present invention has the effect of improving the applicability (adhesion) of foamed fire-resistant paint and maximizing the amount of application by attaching a mesh-shaped film to a surface adjacent to the terminal and connector of the end frame, or by forming straight protrusions, grooves, or bumps to make the surface rough.

[0051]

[0052] Figure 1 is a diagram showing battery modules arranged in series and parallel within a typical battery pack.

[0053] FIG. 2 is a drawing showing a battery module according to the prior art.

[0054] Figure 3 is a diagram showing the state in which flames are ejected near the terminal, which is an open area during thermal runaway of a pouch cell in a battery module according to the prior art.

[0055] FIG. 4 is a drawing showing the outer surface of an end frame, showing a state in which a mesh film is attached to the terminal adjacent area and the connector adjacent area of ​​an end frame in a battery module according to the present invention.

[0056] Figure 5 is a drawing showing the state in which fire-resistant paint is applied to the mesh film of Figure 4.

[0057] FIG. 6 is a drawing showing the inner surface of an end frame, showing a state in which a mesh film with fire-resistant paint applied to the terminal adjacent area and the connector adjacent area of ​​an end frame is attached in a battery module according to the present invention.

[0058] FIG. 7 is a drawing showing that in a battery module according to the present invention, a plurality of straight protrusions are formed side by side across the entire surface of the terminal adjacent area and the connector adjacent area of ​​the end frame.

[0059] FIG. 8 is a drawing showing that a plurality of grooves are formed at predetermined intervals across the entire surface of the terminal adjacent area and the connector adjacent area of ​​the end frame in a battery module according to the present invention.

[0060] FIG. 9 is a drawing showing that a plurality of protrusions are formed at predetermined intervals across the entire surface of the terminal adjacent area and the connector adjacent area of ​​the end frame in a battery module according to the present invention.

[0061] FIG. 10 is a drawing illustrating that when a flame is ejected near a terminal, which is an open area during thermal runaway of a pouch cell in a battery module according to the present invention, the fire-resistant paint is foamed by heat.

[0062] FIG. 11 is a drawing for explaining that when a flame is ejected near a terminal, which is an open area during thermal runaway of a pouch cell in a battery module according to the present invention, the fire-resistant paint is foamed by heat, and the foamed material blocks the inflow of air and prevents the flame from being ejected out of the battery module.

[0063]

[0064] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Accordingly, in some embodiments, well-known process steps, well-known device structures, and well-known techniques are not specifically described to avoid the present invention being interpreted ambiguously. Throughout the specification, like reference numerals refer to like components.

[0065] In drawings, thicknesses may be enlarged to clearly represent multiple layers and regions. Throughout the specification, the same reference numerals are used for similar parts. When a part such as a layer, film, region, or plate is described as being "above" another part, this includes not only cases where it is "immediately above" another part, but also cases where there is another part in between. Conversely, when a part is described as being "immediately above" another part, it means that there is no other part in between. Furthermore, when a part such as a layer, film, region, or plate is described as being "below" another part, this includes not only cases where it is "immediately below" another part, but also cases where there is another part in between. Conversely, when a part is described as being "immediately below" another part, it means that there is no other part in between.

[0066] FIG. 4 is a drawing showing the outer surface of an end frame in which a mesh film is attached to the terminal adjacent area and the connector adjacent area of ​​an end frame in a battery module according to the present invention, FIG. 5 is a drawing showing the state in which a fire-resistant paint is applied to the mesh film of FIG. 4, and FIG. 6 is a drawing showing the inner surface of an end frame in which a mesh film with a fire-resistant paint applied is attached to the terminal adjacent area and the connector adjacent area of ​​an end frame in a battery module according to the present invention.

[0067] A battery module (10) according to the present invention comprises a cell assembly (not shown), a main body frame (11), and an end frame (12).

[0068] A cell assembly is formed by stacking multiple battery cells and can generate electrical energy.

[0069] The battery cells of this cell assembly serve as basic secondary batteries that act as units for charging and discharging, and can be configured in various forms.

[0070] For example, each battery cell can be composed of a pouch-type secondary battery, a cylindrical secondary battery, or a prismatic secondary battery.

[0071] Electrode leads may be formed at both ends or one end of each of these battery cells.

[0072] Multiple battery cells can be electrically connected to each other in series and / or parallel through electrode leads.

[0073] At this time, the electrode leads of each battery cell may be directly connected by contacting each other, or indirectly connected through a busbar, etc.

[0074] The main body frame (11) has a predetermined length and width and has an internal space enclosed by a plurality of faces, in which a cell assembly is accommodated.

[0075] In addition, an opening is formed on at least one of the two sides in the longitudinal direction of the main body frame (11) that communicates with the internal space.

[0076] The end frame (12) is connected to the opening of the main body frame (11).

[0077] An open area is formed in the end frame (12) so that the terminal (13) and connector (14) are partially exposed to the outside.

[0078] The terminal (13) is a part for connecting the battery module (10) to other external elements, such as another battery module (10) or a pack terminal, and is a terminal through which charging and discharging power flows.

[0079] The terminal (13) can be connected to the electrode lead of the battery cell.

[0080] The terminal (13) can be made of an electrically conductive material, such as a metal material like copper, aluminum, or nickel.

[0081] In the end frame (12), an open area is formed so that the terminal (13) is exposed to the outside at a location corresponding to the terminal (area adjacent to the terminal (TA)).

[0082] The connector (14) can be configured to transmit and receive information between the internal components and the external components of the battery module (10).

[0083] For example, a control unit such as a BMS (Battery Management System) may be provided outside the battery module (10).

[0084] At this time, the BMS is connected to the connector (14) and can collect information such as the voltage or current of the cell assembly, and the temperature inside or outside the battery module.

[0085] In the end frame (12), an open area is formed so that the connector (14) is exposed to the outside at a position corresponding to the connector (area adjacent to the connector (CA)).

[0086] In the present invention, a foamed fire-resistant paint (F) may be applied to surfaces adjacent to the terminal (13) and connector (14) of the end frame (12) (each surface forming an open area).

[0087] Thus, when a flame reaches the open area during thermal runaway of a battery cell within the main body frame (11), the fire-resistant paint (F) is foamed, and the foamed material (30) thus formed closes the open area, thereby blocking air from entering the main body frame (11) and blocking the flame (20) from being ejected outside the main body frame (11).

[0088] In another configuration, the present invention may have a film (15) formed in a mesh shape with a plurality of through holes (15a) formed on a surface (a surface forming an open area) adjacent to the terminal (13) and connector (14) of the end frame (12), and may have a foamed fire-resistant paint (F) applied to such a film (15).

[0089] The through hole (15a) of the mesh-shaped film (15) allows a larger amount of foamed fire-resistant paint (F) to be deposited on the film (15).

[0090] At this time, double-sided tape may be attached or adhesive may be applied to the surface of the end frame (12) to which the mesh-shaped film (15) is attached.

[0091] In addition, it is preferable that the through holes (15a) formed in the film (15) are formed at predetermined intervals over the entire surface area of ​​the film (15).

[0092] Additionally, the shape of these through holes (15a) can be formed in a circular or polygonal shape. For example, the through holes can be square or hexagonal in shape.

[0093] It is preferable that the film (15) in such a mesh form be made of a material with sufficient rigidity, so that the film (15) maintains a stiff shape and maintains the shape of the foamed material (30) formed by the foaming of the foamed fire-resistant paint (F).

[0094] In this way, a mesh-shaped film (15) is attached to the surface adjacent to the terminal (13) and connector (14) of the end frame (12) (the surface forming the open area), and then a foamed fire-resistant paint (F) is applied over the film (15), thereby allowing the fire-resistant paint (F) to maintain the shape of the char layer created by exposure to the flame (20).

[0095]

[0096] FIG. 7 is a drawing showing that in a battery module according to the present invention, a plurality of straight protrusions are formed side by side across the entire surface of the terminal adjacent area and the connector adjacent area of ​​the end frame.

[0097] Instead of attaching a mesh-shaped film to the surface adjacent to the terminal (13) and connector (14) of the end frame (12) (the surface forming the open area), a plurality of straight protrusions (12a) can be formed side by side on the surface adjacent to the terminal (13) and connector (14) of the end frame (12).

[0098] These protrusions (12a) can be formed, for example, in a horizontal direction, a vertical direction, a diagonal direction, or a mixed direction thereof.

[0099] At this time, it is preferable to form the heights of the multiple protrusions (12a) equally.

[0100] In this way, a straight protrusion (12a) is formed on the surface adjacent to the terminal (13) and connector (14) of the end frame (12), and then a foamed fire-resistant paint (F) can be applied to the surface of the end frame (12) including such a protrusion (12a). A larger amount of foamed fire-resistant paint (F) can be stably settled between mutually adjacent protrusions (12a).

[0101]

[0102] FIG. 8 is a drawing showing that a plurality of grooves are formed at predetermined intervals across the entire surface of the terminal adjacent area and the connector adjacent area of ​​the end frame in a battery module according to the present invention.

[0103] Instead of attaching a mesh-shaped film to the surface adjacent to the terminal (13) and connector (14) of the end frame (12) (the surface forming the open area), a plurality of grooves (12b) of a predetermined shape can be formed on the surface adjacent to the terminal (13) and connector (14) of the end frame (12).

[0104] These grooves (12b) may, for example, be circular grooves or polygonal grooves, may have both circular and polygonal grooves, or may have both n-gonal and m-gonal grooves. (Here, n and m represent numbers.)

[0105] At this time, it is desirable to form the depth of the groove (12b) equally.

[0106] In this way, a predetermined groove (12b) is formed on the surface adjacent to the terminal (13) and connector (14) of the end frame (12), and then a foamed fire-resistant paint (F) can be applied to the surface of the end frame (12) including the groove (12b).

[0107]

[0108] FIG. 9 is a drawing showing that a plurality of protrusions are formed at predetermined intervals across the entire surface of the terminal adjacent area and the connector adjacent area of ​​the end frame in a battery module according to the present invention.

[0109] Instead of attaching a mesh-shaped film to the surface adjacent to the terminal (13) and connector (14) of the end frame (12) (the surface forming the open area), a plurality of protrusions (12c) of a predetermined shape can be formed on the surface adjacent to the terminal (13) and connector (14) of the end frame (12).

[0110] These protrusions (12c) can be formed, for example, in the shape of a disc, a polygonal plate including a square plate, or a mixture of disc-shaped protrusions and polygonal plate-shaped protrusions.

[0111] At this time, it is desirable to form the height of the protrusion (12c) equally.

[0112] In this way, a predetermined protrusion (12c) is formed on the surface adjacent to the terminal (13) and connector (14) of the end frame (12), and then a foamed fire-resistant paint (F) can be applied to the surface of the end frame (12) including the protrusion (12c). A larger amount of foamed fire-resistant paint (F) can be stably settled between adjacent protrusions (12c).

[0113] As described above, the present invention has the advantage of improving the applicability (adhesion) of the foamed fire-resistant paint (F) and maximizing the amount of application by attaching a mesh-shaped film (15) to the surface adjacent to the terminal (13) and connector (14) of the end frame (12), or by forming a straight protrusion (12a), a groove (12b), or a projection (12c) to make the surface rough.

[0114]

[0115] FIG. 10 is a drawing to explain that when a flame is ejected near a terminal, which is an open area during thermal runaway of a pouch cell in a battery module according to the present invention, the fire-resistant paint is foamed by heat, and FIG. 11 is a drawing to explain that when a flame is ejected near a terminal, which is an open area during thermal runaway of a pouch cell in a battery module according to the present invention, the fire-resistant paint is foamed by heat, and the foamed material blocks the inflow of air and prevents the flame from being ejected out of the battery module.

[0116] When multiple battery modules (10) are included inside a battery pack (1), they may be vulnerable to thermal chain reactions between the battery modules (10).

[0117] For example, if a flame (20) is ejected due to thermal runaway inside one battery module (10), this flame (20) can be transferred to another battery module (10).

[0118] In the present invention, a mesh-shaped film (15) is attached to the surface adjacent to the terminal (13) and connector (14) of the end frame (12), or a straight protrusion (12a), groove (12b), or projection (12c) is formed to make the surface rough, and then a foamed fire-resistant paint (F) is applied to the surface adjacent to the terminal (13) and connector (14) of the end frame (12). As a result, when a flame (20) is ejected due to thermal runaway inside one of the battery modules (10), the applied fire-resistant paint (F) expands due to heat, and the foamed material (30) generated by this expansion closes the open area of ​​the end frame (12) adjacent to the terminal (13) and connector (14).

[0119] Accordingly, the foam material (30) blocks air from entering the battery module (10) and at the same time blocks the flame (20) from being ejected outside the battery module (10).

[0120] In this way, by producing a heat shielding effect and a combustion delay effect, it is possible to delay the transfer of thermal runaway to adjacent battery modules (10).

[0121]

[0122] The present invention described above is not limited by the aforementioned embodiments and attached drawings, and it will be obvious to those skilled in the art that various substitutions, modifications, and changes are possible within the scope of the technical concept of the present invention.

[0123]

[0124] [Explanation of the symbol]

[0125] 1 : Battery pack

[0126] 10: Battery Module

[0127] 11: Main body frame

[0128] 12 : End frame

[0129] TA: Terminal Adjacent Area

[0130] CA: Connector Adjacent Area

[0131] 12a: Straight protrusion

[0132] 12b : Home

[0133] 12c : protrusion

[0134] 13 : Terminal

[0135] 14 : Connector

[0136] 15: Mesh film

[0137] 15a : Through hole

[0138] 19 : Battery cell

[0139] F: Foaming refractory paint

[0140] 20: Flame

[0141] 30: Foam material

Claims

1. A cell assembly comprising a plurality of battery cells; A main body frame having a predetermined length and width, accommodating the cell assembly inside, and having an opening formed on at least one of the two sides in the longitudinal direction; and It includes an end frame coupled to an opening of the main body frame and having an opening formed so that a terminal and a connector are partially exposed to the outside; A foamed fire-resistant paint is applied to the surface adjacent to the terminal and the connector of the end frame, so that when a flame reaches the open area during thermal runaway of the battery cell within the main body frame, the foamed material formed by the foaming of the fire-resistant paint due to heat closes the open area. Battery module.

2. In Paragraph 1, A film having a plurality of through holes formed to form a mesh shape is attached to the surface adjacent to the terminal and the connector of the end frame, and a foamed fire-resistant paint is applied to the film. Battery module.

3. In Paragraph 2, The above through holes are formed at predetermined intervals across the entire surface area of ​​the film, Battery module.

4. In Paragraph 3, The shape of the above through hole is formed in a circular or polygonal shape, Battery module.

5. In Paragraph 1, On the surface adjacent to the terminal and the connector of the end frame, Multiple straight-shaped protrusions are formed side by side, The foamed fire-resistant paint is applied to the surface of the end frame including the above protrusion. Battery module.

6. In Paragraph 1, On the surface adjacent to the terminal and the connector of the end frame, A plurality of grooves of a predetermined shape are formed, and The foamed fire-resistant paint is applied to the surface of the end frame including the above groove. Battery module.

7. In Paragraph 1, On the surface adjacent to the terminal and the connector of the end frame, Multiple protrusions of a predetermined shape are formed, The foamed fire-resistant paint is applied to the surface of the end frame including the above protrusions. Battery module.

8. A battery pack comprising a battery module according to any one of paragraphs 1 through 7.

Images