CN117397093A

CN117397093A - Battery module with enhanced safety

Info

Publication number: CN117397093A
Application number: CN202380011841.XA
Authority: CN
Inventors: 张诚桓; 朴明基; 成准烨
Original assignee: LG Energy Solution Ltd
Current assignee: LG Energy Solution Ltd
Priority date: 2022-03-31
Filing date: 2023-03-28
Publication date: 2024-01-12

Abstract

A battery module having an improved structure for enhancing safety upon a thermal event in the battery module is disclosed. A battery module according to an aspect of the present invention includes: a plurality of battery cells stacked in at least one direction; a module housing accommodating a plurality of battery cells in an interior space; and a blocking member interposed between the adjacent battery cells and having a heat transfer prevention part configured to block heat transfer between the adjacent battery cells and a flame transfer prevention part disposed inside the heat transfer prevention unit to block flames between the adjacent battery cells.

Description

Battery module with enhanced safety

Technical Field

The present application claims priority from korean patent application No. 10-2022-0040406, which was filed on 3 months of 2022, 31, and korean patent application No. 10-2023-0029081, which was filed on 6 months of 2023, 3, the disclosures of which are incorporated herein by reference.

The present disclosure relates to a battery, and more particularly, to a battery module with enhanced safety, and a battery pack and a vehicle including the same.

Background

With the greatly increasing demand for portable electronic products such as smartphones, tablet computers, smartwatches and the widespread use of electric automobiles, batteries mounted thereon, particularly secondary batteries capable of being repeatedly charged and discharged, are being actively studied.

The secondary batteries commercialized at present include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, lithium secondary batteries, and the like. Among them, the lithium secondary battery has little memory effect compared to the nickel-based secondary battery to ensure free charge and discharge, and the lithium secondary battery is receiving attention due to a very low discharge rate and high energy density.

Lithium secondary batteries mainly use lithium-based oxides and carbon materials as a positive electrode active material and a negative electrode active material, respectively. The lithium secondary battery includes an electrode assembly in which positive and negative electrode plates respectively coated with a positive and negative electrode active material are disposed with a separator interposed therebetween, and an external member or a battery case for hermetically accommodating the electrode assembly with an electrolyte.

Generally, lithium secondary batteries can be classified into can-type secondary batteries having an electrode assembly included in a metal can and pouch-type secondary batteries having an electrode assembly included in a pouch of an aluminum laminate sheet, according to the shape of an external member.

Recently, secondary batteries are widely used for driving or energy storage not only in small-sized devices such as portable electronic devices but also in large-sized devices such as electric vehicles and Energy Storage Systems (ESS). These secondary batteries may constitute one battery module in such a manner that a plurality of secondary batteries are electrically connected and stored together in a module case. In addition, a plurality of battery modules may be connected to form one battery pack.

However, when a plurality of secondary batteries (battery cells) or a plurality of battery modules are concentrated in a narrow space as described above, they may be susceptible to thermal events. In particular, when an event such as thermal runaway occurs inside any one of the battery cells, high temperature gas, flame, or heat may be generated. If gas, flame, or heat is transferred to another battery cell included in the same battery module, an explosion chain reaction condition such as heat propagation may occur. In addition, such a chain reaction may cause an accident such as a fire or explosion in the corresponding battery module, and may also cause a fire or explosion in other battery modules.

Furthermore, in the case of a medium-or large-sized battery module or battery pack, such as an electric vehicle, a large number of battery cells are included to increase output and/or capacity, so that the risk of thermal chain reaction may increase. Further, in the vicinity of a battery pack mounted to an electric vehicle or the like, there may be a user such as a driver. Thus, if a thermal event occurring in a specific battery module is not properly controlled and a chain reaction occurs, it may cause not only great damage to property but also personal injury.

Disclosure of Invention

Technical problem

The present disclosure is designed to solve the problems of the related art, and therefore, it is an object of the present disclosure to provide a battery module having an improved structure, and a battery pack and a vehicle including the same, to enhance safety when a thermal event occurs inside the battery module.

However, the technical problems to be solved by the present disclosure are not limited to the above-described problems, and other problems not mentioned herein will be clearly understood by those skilled in the art from the following disclosure.

Technical proposal

In one aspect of the present disclosure, there is provided a battery module including: a plurality of battery cells stacked in at least one direction; a module housing configured to accommodate the plurality of battery cells in an interior space of the module housing; and a blocking member interposed between the adjacent battery cells and including a heat transfer prevention unit configured to prevent heat transfer between the adjacent battery cells and a flame transfer prevention unit disposed to an inner side of the heat transfer prevention unit and configured to block flames between the adjacent battery cells.

Here, the heat transfer preventing unit may be made of a material having a lower thermal conductivity than the flame transfer preventing unit.

Further, the flame transfer prevention unit may be made of a material having a higher melting point than the heat transfer prevention unit.

Further, the blocking member may be configured to expose the flame transfer prevention unit toward the battery cell when the heat transfer prevention unit is melted.

Further, the blocking member may be configured in a sheet form.

Further, the blocking member may be configured such that the flame transfer preventing sheet is inserted inside the heat transfer preventing sheet.

Furthermore, the blocking member may be configured to absorb the swelling of the battery cells.

Further, the heat transfer preventing unit may be formed such that the center portion has a greater thickness than the end portions.

Further, the flame transfer prevention unit may have a groove formed in a concave shape in the central portion.

Further, the flame transfer prevention unit may be configured such that at least one side of the groove formed in the central portion is open to the outside.

Further, each of the plurality of battery cells may be a pouch-type secondary battery having a receiving portion and a sealing portion, and the flame transfer preventing unit may be formed such that a portion facing the sealing portion between the plurality of battery cells has a greater thickness than a portion facing the receiving portion.

Further, the blocking members may be arranged in a plurality of blocking members along the stacking direction of the plurality of battery cells, and two or more of the plurality of blocking members may be configured to have different compression ratios.

Further, the plurality of battery cells may include two or more cell groups connected in series, and the blocking member may be interposed between different cell groups.

In another aspect of the present disclosure, there is also provided a battery pack including the battery module according to the present disclosure.

In yet another aspect of the present disclosure, there is also provided a vehicle including the battery module according to the present disclosure.

Advantageous effects

According to the present disclosure, when a thermal event occurs inside the battery module, the event can be effectively controlled.

In particular, according to embodiments of the present disclosure, when gas, flame, or heat is generated from a specific battery cell inside a battery module, propagation of the gas and/or heat to other battery cells included in the corresponding battery module may be blocked.

Further, according to embodiments of the present disclosure, when a large amount of heat is generated due to the occurrence of a thermal event, heat transfer between the cells may be blocked, and when flame is generated due to the aggravation of the thermal event, flame transfer between the cells may be blocked.

That is, in the present disclosure, event control such as heat blocking and flame blocking may be appropriately and sequentially performed according to the degree of the thermal event.

Therefore, according to the embodiments of the present disclosure, since the regions are divided between the cells or between the cell groups inside the battery module, even if a thermal event occurs in a specific battery cell, it is possible to prevent the explosion chain reaction from occurring.

Further, according to this embodiment of the present disclosure, the possibility of fire or explosion of the battery module may be reduced, or the time may be delayed. In particular, when the fire or explosion time of the battery module is delayed, it is possible to ensure that a battery user, such as a vehicle driver, has sufficient time to evacuate, thereby reducing personal injury.

In addition to the above-described effects, the present disclosure may have various other effects, and such effects will be described in each embodiment, or any effects that can be easily inferred by those skilled in the art will not be described in detail.

Drawings

The accompanying drawings illustrate preferred embodiments of the present disclosure and together with the foregoing disclosure serve to provide a further understanding of the technical features of the present disclosure, and thus the present disclosure is not to be construed as limited to the accompanying drawings.

Fig. 1 is an assembled perspective view schematically illustrating a battery module according to an embodiment of the present disclosure, and fig. 2 is an exploded perspective view illustrating the battery module of fig. 1.

Fig. 3 is a sectional view taken along line A1-A1 'of fig. 1, and fig. 4 is a sectional view taken along line A2-A2' of fig. 1.

Fig. 5 is a perspective view schematically illustrating a configuration of a blocking member according to an embodiment of the present disclosure.

Fig. 6 and 7 are a sectional view taken along line A3-A3 'of fig. 5 and a sectional view taken along line A4-A4' of fig. 5.

Fig. 8 is a cross-sectional view schematically showing a configuration of a blocking member according to another embodiment of the present disclosure.

Fig. 9 is a sectional view schematically showing a partial sectional configuration of a battery module according to another embodiment of the present disclosure.

Fig. 10 is an exploded cross-sectional view showing the configuration of fig. 9.

Fig. 11 is a sectional view schematically showing a partial configuration of a blocking member according to an embodiment of the present disclosure.

Fig. 12 is a sectional view schematically showing a configuration of a blocking member according to still another embodiment of the present disclosure.

Fig. 13 is a sectional view schematically showing a configuration of a blocking member according to still another embodiment of the present disclosure.

Fig. 14 is a sectional view schematically showing a configuration of a blocking member according to still another embodiment of the present disclosure.

Fig. 15 is a sectional view schematically showing a configuration of a blocking member according to still another embodiment of the present disclosure.

Fig. 16 is a perspective view schematically showing the configuration of a flame transfer preventing unit provided in a blocking member according to still another embodiment of the present disclosure.

Fig. 17 is a perspective view schematically showing the configuration of a flame transfer preventing unit provided in a blocking member according to still another embodiment of the present disclosure.

Fig. 18 is a perspective view schematically showing the configuration of a flame transfer preventing unit provided in a blocking member according to still another embodiment of the present disclosure.

Fig. 19 is a sectional view taken along line A4-A4' of fig. 18.

Fig. 20 is a diagram schematically showing a partial configuration of a battery module according to an embodiment of the present disclosure when viewed from the top.

Fig. 21 is an exploded perspective view illustrating a partial configuration of a battery module according to still another embodiment of the present disclosure.

Fig. 22 and 23 are diagrams showing the configuration of different blocking members included in the battery module of fig. 21.

Fig. 24 is an exploded perspective view illustrating a battery module according to still another embodiment of the present disclosure.

Fig. 25 is a sectional view of the battery module of fig. 24.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Before the description, it should be understood that the terms used in the specification and the appended claims should not be construed as limited to general and dictionary meanings, but interpreted based on the meanings and concepts corresponding to technical aspects of the present disclosure on the basis of the principle that the inventor is allowed to define terms appropriately for the best explanation.

Accordingly, the description set forth herein is merely a preferred example for the purpose of illustration and is not intended to limit the scope of the disclosure, and it is therefore to be understood that other equivalents and modifications may be made thereto without departing from the scope of the disclosure.

Fig. 1 is an assembled perspective view schematically illustrating a battery module according to an embodiment of the present disclosure, and fig. 2 is an exploded perspective view illustrating the battery module of fig. 1. Further, fig. 3 is a sectional view taken along a line A1-A1 'of fig. 1, and fig. 4 is a sectional view taken along a line A2-A2' of fig. 1.

Referring to fig. 1 to 4, a battery module according to the present disclosure includes a battery cell 100, a module case 200, and a blocking member 300.

A plurality of battery cells 100 may be included in a battery module. In addition, each battery cell 100 may represent a secondary battery. The secondary battery may include an electrode assembly (including a positive electrode plate, a negative electrode plate, and a separator), an electrolyte, and a battery case. The plurality of battery cells 100 may be electrically connected to each other. For example, the plurality of battery cells 100 may be electrically connected in series and/or parallel with each other by bus bars or the like.

A plurality of battery cells 100 may be included in a battery module in a stacked form. That is, it can be considered that the battery cells 100 according to the present disclosure are stacked in at least one direction to configure a cell stack (cell assembly). For example, as shown in fig. 2, a plurality of battery cells 100 may be arranged side by side in the left-right direction (Y-axis direction).

The module case 200 has an empty space therein, and may be configured to accommodate the plurality of battery cells 100 in the inner space. For example, the module case 200 may include an upper plate 210, a lower plate 220, a left plate 230, a right plate 240, a front plate 250, and a rear plate 260 to define an inner space. Furthermore, the cell stack may be positioned in a defined interior space. Here, the module case 200 may be made of a metal and/or plastic material.

In addition, at least some of the various plate-like members constituting the module case 200 may be configured in an integrated form with each other. For example, as shown in fig. 2, the module case 200 may have a U-shaped frame-type body in which a lower plate 220, a left plate 230, and a right plate 240 are integrated with each other, and the upper plate 210, the front plate 250, and the rear plate 260 may be configured to cover or seal the top, front, and rear sides of the body. In this case, various fastening methods such as welding, bonding, bolting, and hooking may be used to couple and fix the upper plate 210, the front plate 250, and the rear plate 260 to the main body. Alternatively, the module case 200 may be configured in a single frame form in which the upper plate 210, the lower plate 220, the left plate 230, and the right plate 240 are integrated with each other. However, the present disclosure is not limited to a particular material or shape of the module housing 200.

The blocking member 300 may be interposed between adjacent battery cells 100. For example, the blocking member 300 may be interposed between at least some battery cells 100 among the plurality of battery cells 100 stacked in the left-right direction. Further, the blocking member 300 may be provided in plurality, and the plurality of blocking members 300 may be provided to be spaced apart from each other in the stacking direction of the battery cells 100. In addition, the blocking member 300 may be interposed between different battery cells 100. As a more specific example, one blocking member 300 may be provided for every three or four battery cells 100. In this case, it may be considered that three or four battery cells 100 are positioned between two blocking members 300 adjacent to each other but spaced apart from each other. The blocking member 300 will be described in more detail with reference to fig. 5 to 7.

Fig. 5 is a perspective view schematically illustrating a configuration of a blocking member according to an embodiment of the present disclosure. Further, fig. 6 and 7 are a sectional view taken along the line A3-A3 'of fig. 5 and a sectional view taken along the line A4-A4' of fig. 5.

Referring to fig. 5 to 7, the blocking member 300 includes a heat transfer preventing unit 310 and a flame transfer preventing unit 320.

Here, the heat transfer prevention unit 310 may be configured to prevent heat transfer between the battery cells 100. That is, the heat transfer prevention unit 310 may be interposed between different battery cells 100 to prevent or inhibit heat generated from one battery cell 100 from being transferred to another battery cell 100.

The flame transfer prevention unit 320 may be disposed inside the heat transfer prevention unit 310. For example, the heat transfer prevention unit 310 may be disposed to cover all or a portion of the outer surface of the flame transfer prevention unit 320. That is, the flame transfer prevention unit 320 may be configured to be embedded in the heat transfer prevention unit 310. Further, the flame transfer prevention unit 320 may be configured to block flame transfer between the battery cells 100. That is, the flame transfer prevention unit 320 may be configured to prevent or inhibit flames generated from the battery cells 100 at one side from moving to the battery cells 100 at the opposite side. The heat transfer preventing unit 310 is configured to block heat between the cells, and the flame transfer preventing unit 320 is configured to block flames between the cells, and the heat transfer preventing unit 310 and the flame transfer preventing unit 320 may be made of different materials.

For convenience of distinction or description, terms such as the heat transfer preventing unit 310 and the flame transfer preventing unit 320 are used, but are not necessarily limited thereto. In this regard, the heat transfer prevention unit 310 and the flame transfer prevention unit 320 may be replaced with a first prevention unit and a second prevention unit, respectively.

The heat transfer preventing unit 310 and the flame transfer preventing unit 320 may be coupled by various fastening methods, such as coating, bonding, welding, and bolting. For example, the heat transfer prevention unit 310 may be configured to be coated on all or a portion of the outer surface of the flame transfer prevention unit 320. Alternatively, the heat transfer preventing unit 310 may be configured to be adhered to the outer surface of the flame transfer preventing unit 320 by an adhesive.

According to this configuration of the present disclosure, when a thermal event occurs inside the battery module, the thermal event can be effectively suppressed. In particular, according to the embodiments of the present disclosure, when a thermal runaway condition occurs in a specific battery cell 100 among a plurality of battery cells 100 included in a battery module, the propagation of thermal runaway to other battery cells 100 may be prevented or reduced. Furthermore, when a thermal event occurs in a particular battery cell 100, heat and flame may be generated together. According to this embodiment, not only heat transfer but also flame transfer can be prevented between the battery cells 100. In particular, according to the embodiment of the present disclosure, in the blocking member 300, even though the thermal conductivity of the flame transfer prevention unit 320 is high, since the heat transfer prevention unit 310 exists at the outer side of the flame transfer prevention unit 320, heat transfer between the battery cells can be suppressed by the heat transfer prevention unit 310.

Preferably, the heat transfer prevention unit 310 may be made of a material having a lower thermal conductivity than the flame transfer prevention unit 320. In particular, the heat transfer prevention unit 310 may be made of a heat insulating material to prevent or reduce heat transfer between the adjacent battery cells 100. For example, the heat transfer prevention unit 310 may be made of silicone, polyurethane, or the like. In addition, the heat transfer preventing unit 310 may employ various insulating materials known at the time of filing the present application.

According to this embodiment, the effect of preventing heat transfer between the battery cells can be more effectively achieved by the blocking member 300. In addition, when a thermal event occurs in a specific battery cell 100, a large amount of heat may be initially generated. According to this embodiment, the transfer of generated heat to another battery cell 100 can be suppressed or reduced. Further, according to this embodiment, by reducing the weight of the blocking member 300, it is possible to more easily reduce the weight of the entire battery module.

In addition, the flame transfer preventing unit 320 may be made of a material having a higher melting point than the heat transfer preventing unit 310. In particular, the flame transfer prevention unit 320 may be made of a flame retardant or heat resistant material to prevent or reduce flame transfer between adjacent battery cells 100. For example, the flame transfer preventing unit 320 may include a metal material, such as SUS (stainless steel). Alternatively, the flame transfer prevention unit 320 may include at least one material of GFRP (glass fiber reinforced plastic) and CFRP (carbon fiber reinforced plastic). Further, the flame transfer preventing unit 320 may be made of a metal material such as aluminum or in the form of an alloy including such a metal material.

According to this embodiment, an effective flame barrier performance can be achieved. Further, in this case, the structural strength of the blocking member may be improved, and it may be advantageous to reduce the manufacturing cost or weight of the battery module. In addition, the flame transfer preventing unit 320 may employ various flame blocking materials known at the time of filing the present application, such as a ceramic material.

According to this embodiment of the present disclosure, when a thermal event such as thermal runaway is exacerbated to generate a flame, flame propagation between the cells can be prevented. Accordingly, the spread of the fire to the entire battery module due to the flame propagation between the battery cells 100 may be suppressed or the speed thereof may be delayed.

Further, according to this embodiment, since the flame transfer preventing unit 320 may be made of a material having higher structural rigidity than the thermal transfer preventing unit 310, the mechanical strength of the blocking member 300 may be further improved. Further, therefore, the heat insulation performance of the heat transfer prevention unit 310 can also be stably ensured. Further, according to this embodiment, even if the heat transfer preventing unit 310 is melted and disappeared due to the flame generated inside the battery module, the shape of the blocking member 300 may be stably maintained by the flame transfer preventing unit 320. Therefore, it is possible to restrain structural collapse of the battery module in the event of a fire.

Further, the blocking member 300 may be configured to expose the flame transfer preventing unit 320 toward the battery cell 100 when the heat transfer preventing unit 310 is melted. That is, the blocking member 300 may be configured such that the flame transfer preventing unit 320 does not directly face the battery cell 100 in a state in which the heat transfer preventing unit 310 is not melted. For example, referring to fig. 6, the heat transfer preventing unit 310 may be configured to cover left and right surfaces of the flame transfer preventing unit 320. Accordingly, in a state where the heat transfer preventing unit 310 is present, the left and right surfaces of the flame transfer preventing unit 320 may not be exposed to the left and right battery cells 100 and 100. However, when heat of a temperature higher than the melting point of the heat transfer preventing unit 310 is applied to the blocking member 300 due to the generation of flame or high temperature gas, the heat transfer preventing unit 310 may be melted. At this time, the heat transfer preventing unit 310 may be melted or lost such that a surface (e.g., a left surface and/or a right surface in fig. 6) of the flame transfer preventing unit 320 may be exposed to the outside. Accordingly, the flame transfer preventing unit 320 is interposed between the two battery cells 100 located at the left and right sides of the blocking member 300, and flame propagation between the two battery cells 100 can be blocked by the flame transfer preventing unit 320.

According to this embodiment of the present disclosure, in the blocking member 300, the heat transfer preventing unit 310 may be positioned closer to the battery cell 100 than the flame transfer preventing unit 320. Therefore, even if the thermal conductivity of the flame transfer prevention unit 320 is high, heat transfer between the battery cells 100 may be first blocked due to the heat transfer prevention unit 310 having low thermal conductivity.

Further, the blocking member 300 may be configured such that the entire outside of the flame transfer preventing unit 320 is surrounded by the heat transfer preventing unit 310. That is, the blocking member 300 may be configured such that the heat transfer preventing unit 310 covers the entire surface of the flame transfer preventing unit 320. For example, referring to the embodiments shown in fig. 5 to 7, etc., the heat transfer preventing unit 310 may be configured to cover all of the left, right, upper, lower, front and rear sides of the flame transfer preventing unit 320. In this case, the heat discharged from the heat transfer prevention unit 310 may be blocked by the heat transfer prevention unit 310 before reaching the flame transfer prevention unit 320. Therefore, the insulation performance of the blocking member 300 may be more stably ensured with respect to the heat discharged from the battery cell 100 before the heat transfer preventing unit 310 melts or disappears.

Further, the blocking member 300 may be configured in a sheet form. Here, the sheet may be replaced with terms such as a plate or a pad. For example, the blocking member 300 may be configured in the form of a sheet having two broad surfaces, as shown in fig. 5 and the like. In the configuration of the blocking member 300 as described above, two broad surfaces may be provided to face the battery cell 100. That is, the blocking member 300 may be interposed between two battery cells 100, and when the blocking member 300 is configured in a sheet form, two wide surfaces may be disposed to face different battery cells 100, respectively. For example, referring to the embodiment of fig. 3, the blocking member 300 has two broad surfaces, i.e., a left surface and a right surface, wherein the left surface may face the battery cell 100 located at the left side and the right surface may face the battery cell 100 located at the right side.

According to this embodiment of the present disclosure, the blocking member 300 may be more easily interposed between the battery cells 100 by the blocking member 300 configured in the form of a sheet. Further, in this case, it is possible to prevent the volume of the battery module from greatly increasing due to the blocking member 300.

In addition, the blocking member 300 may be configured in such a manner that the flame transfer preventing sheet is inserted inside the heat transfer preventing sheet. In particular, in an embodiment in which the blocking member 300 is configured in a sheet form, the heat transfer preventing unit 310 and the flame transfer preventing unit 320 included in the blocking member 300 may also be configured in sheet forms, respectively. In this case, the heat transfer preventing unit 310 and the flame transfer preventing unit 320 may be referred to as a heat transfer preventing sheet and a flame transfer preventing sheet, respectively.

For example, the blocking member 300 may be configured in a form in which a flame transfer preventing sheet is inserted inside a heat transfer preventing sheet having an empty space therein, as in the embodiment of fig. 5 to 7. In this case, it can be considered that the blocking member 300 is configured such that the heat transfer preventing sheet is coated on the outer side of the flame transfer preventing sheet.

According to this embodiment, the blocking member 300 can be easily manufactured. Further, according to this embodiment, the flame transfer preventing unit 320 is included inside the heat transfer preventing unit 310, and the blocking member 300 having a sheet form can be easily implemented.

Fig. 8 is a cross-sectional view schematically showing a configuration of a blocking member according to another embodiment of the present disclosure. For example, FIG. 8 may be viewed as another modification of the cross-sectional configuration taken along line A3-A3' of FIG. 5. The same or similar features as those of other embodiments will not be described in detail for various embodiments (including the embodiment) included in the specification, and features different therefrom will be described in detail.

Referring to fig. 8, the blocking member 300 may be configured such that a portion of the outer surface of the flame transfer preventing unit 320 is surrounded by the heat transfer preventing unit 310, and the other portion is not surrounded by the heat transfer preventing unit 310. In particular, when the blocking member 300 is configured in a sheet form, the flame transfer prevention unit 320 may also be configured in a sheet form. At this time, both wide surfaces of the flame transfer preventing unit 320 may be covered by the heat transfer preventing unit 310, and other edge portions may be configured to be exposed to the outside without being covered by the heat transfer preventing unit 310. For example, referring to the embodiment shown in fig. 8, the flame transfer preventing unit 320 has two wide surfaces, i.e., left and right surfaces, and edges may be located at the upper side, the lower side, the front side, and the rear side, respectively. At this time, the heat transfer preventing unit 310 may be located at the outer sides of the left and right surfaces of the flame transfer preventing unit 320, and may not be located at the edges of the flame transfer preventing unit 320, i.e., not at the upper, lower, front and rear sides. In particular, the heat transfer prevention unit 310 may use a two heat transfer sheet configuration, the flame transfer prevention unit 320 may use one flame transfer sheet configuration, and the flame transfer sheet may be interposed between the two heat transfer sheets. That is, two heat transfer sheets may be attached to the left and right surfaces of the flame transfer sheet.

According to this embodiment of the present disclosure, the blocking member 300 may be more easily manufactured. In addition, according to this embodiment, even if the heat transfer preventing unit 310 is lost by flame, the entire height of the blocking member 300 can be maintained as it is. Accordingly, the flame transfer blocking effect by the blocking member 300 inside the battery module can be maintained as it is. For example, in the embodiment of fig. 3, the upper ends of the blocking members 300 interposed between the battery cells 100 stacked in the left-right direction may be configured to be in direct contact with the inner surface of the upper plate 210 of the module case 200, as shown in part B1. At this time, if there is no heat transfer preventing unit 310 at the upper side of the flame transfer preventing unit 320 as in the embodiment of fig. 8, the tip of the flame transfer preventing unit 320 may be in direct contact with the upper plate 210 of the module case 200. Therefore, even if flame is generated and the heat transfer preventing unit 310 is removed, the sealing state between the tip of the flame transfer preventing unit 320 and the module case 200 may be maintained as it is. Accordingly, the flame blocking effect can be stably ensured by the flame transfer preventing unit 320. Further, in this case, even if the heat transfer preventing unit 310 is removed, the position of the blocking member 300 inside the module case 200 can be stably maintained.

Fig. 9 is a sectional view schematically showing a partial sectional configuration of a battery module according to another embodiment of the present disclosure. For example, fig. 9 is an enlarged view showing a modification of the portion B1 of fig. 3. Further, fig. 10 is an exploded sectional view showing the configuration of fig. 9. That is, fig. 10 may be regarded as showing a configuration in which the blocking member 300 is separated from the module case 200 in the configuration of fig. 9.

Referring to fig. 9 and 10, the end of the blocking member 300 may be inserted into the module case 200. In this case, an insertion groove may be formed in the module case 200 such that the end of the blocking member 300 is inserted therein. For example, as shown in G1 of fig. 10, an insertion groove may be formed on an inner side surface of the module case 200. Further, an end of the blocking member 300, for example, a tip end of the blocking member 300 may be inserted into the insertion groove G1 of the module case 200.

According to this embodiment of the present disclosure, the blocking member 300 may be stably fixed inside the module case 200 due to the mating configuration between the blocking member 300 and the module case 200.

In particular, in an embodiment in which the end of the blocking member 300 is inserted into the module case 200, the flame transfer preventing unit 320 provided in the blocking member 300 may be configured to be inserted into the insertion groove of the module case 200. For example, as shown in fig. 9, when the tip end of the blocking member 300 is inserted into the insertion groove G1 of the module case 200, the flame transfer preventing unit 320 may be inserted into the insertion groove G1 of the module case 200 by a length shown as B2. That is, even in a state where the heat transfer preventing unit 310 exists in the blocking member 300, the flame transfer preventing unit 320 may have a form of being inserted into the module case.

According to this embodiment of the present disclosure, even if the heat transfer preventing unit 310 is melted or lost by the flame, the flame transfer preventing unit 320 may be maintained in a state of being inserted into the insertion groove G1 of the module case 200 as it is. In particular, as in the embodiment of fig. 9 and 10, in the case where the blocking member 300 is configured in a state where an end portion, for example, an upper end, of the flame transfer preventing unit 320 is covered with the heat transfer preventing unit 310, the flame transfer preventing unit 320 may not deviate from the insertion groove G1 of the module case 200 even if the heat transfer preventing unit 310 is melted and lost. Therefore, in this case, the position of the blocking member 300 can be maintained even after the flame is generated, and the flame can be suppressed from being transferred toward the end of the blocking member 300, for example, upward as much as possible.

Furthermore, the blocking member 300 may be configured to absorb the swelling of the battery cell 100. This will be described in more detail with reference to fig. 11.

Fig. 11 is a sectional view schematically showing a partial configuration of the blocking member 300 according to the embodiment of the present disclosure. For example, fig. 11 may be regarded as a configuration showing a modification of the portion B3 of fig. 6.

Referring to fig. 11, in the blocking member 300, the heat transfer preventing units 310 in sheet form, i.e., the left heat transfer sheet 310L and the right heat transfer sheet 310R, may be located at left and right surfaces of the flame transfer preventing units 320 configured in sheet form. Further, the battery cells 100 may be disposed at left and right sides of the blocking member 300, respectively. At this time, when the swelling phenomenon occurs in the battery cell 100 positioned at the left or right side of the blocking member 300, pressure is applied to the blocking member 300. For example, referring to the embodiment of fig. 11, when an bulge phenomenon occurs in the battery cell 100 located at the left side of the blocking member 300, the blocking member 300 may be pressed in the right direction as indicated by an arrow D1. At this time, the heat transfer preventing unit 310 may be configured to absorb the pressure and deform the shape. That is, the left surface of the left heat transfer sheet 310L may have a shape indicated by a broken line C1 before the left battery cell 100 is inflated. However, when the bulge occurs in the left battery cell 100, the left heat transfer sheet 310L is pushed in the right direction (-Y axis direction), and the left surface may have a shape as shown by a solid line C2. At this time, the left heat transfer sheet 310L may be configured such that the shape of the right surface is maintained even if the shape of the left surface is deformed due to the pressure caused by the swelling of the battery cell 100. Further, the left heat transfer sheet 310L may be configured such that the entire left heat transfer sheet 310L or the right surface thereof does not move in the right direction regardless of the pressure applied to the left surface.

To this end, the heat transfer prevention unit 310 may be at least partially made of an elastic material. For example, the heat transfer prevention unit 310 may be a silicone sheet or a polyurethane sheet. Furthermore, silicone or polyurethane materials can excellently ensure insulation and elasticity. Further, the heat transfer prevention unit 310 may be made of various other materials capable of absorbing volume expansion due to swelling of the battery cell 100, for example, other various elastic materials such as rubber.

According to this embodiment of the present disclosure, due to the heat transfer prevention unit 310 provided in the blocking member 300, heat transfer between the battery cells 100 can be prevented, and also the internal structure of the battery module can be prevented from being deformed or collapsed due to the swelling phenomenon of a specific battery cell 100. Particularly, when the plurality of battery cells 100 are all pouch-type batteries, the swelling phenomenon of the battery cells 100 may be more serious. However, according to this embodiment, the blocking member 300, particularly the heat transfer preventing unit 310, can appropriately respond to the swelling phenomenon of the pouch type battery.

Fig. 12 is a sectional view schematically showing a configuration of a blocking member 300 according to still another embodiment of the present disclosure.

Referring to fig. 12, the heat transfer preventing unit 310 may be configured such that the center portion has a greater thickness than the end portions. More specifically, the heat transfer preventing unit 310 may be configured to stand in a vertical direction (Z-axis direction), and the thickness of the center portion in the vertical direction is shown as E1 in fig. 12. Further, the thickness of the top or bottom end of the heat transfer preventing unit 310 is shown as E2 in fig. 12. In this case, the heat transfer prevention unit 310 may be configured such that E1 is greater than E2. That is, the heat transfer preventing unit 310 may be formed such that the central portion is relatively thick and the thickness gradually increases toward the end portions, for example, toward the upper end, the lower end, the front end, and the rear end.

According to this embodiment of the present disclosure, the heat insulation performance or the swelling absorption performance of the heat transfer prevention unit 310 can be more effectively improved. That is, in the battery cell 100, the volume expansion is most likely to occur generally in the portion facing the central portion of the heat transfer preventing unit 310, and according to this embodiment, since the heat transfer preventing unit 310 is formed relatively thickly in the corresponding portion, the volume expansion can be sufficiently absorbed. In addition, in the battery cell 100, a large amount of heat may be generated in the central portion, and according to this embodiment, since the heat transfer prevention unit 310 in the central portion is sufficiently formed, heat transfer in the corresponding portion may be effectively prevented. In particular, when the battery cell 100 is a pouch-type battery, the central portion may be a portion facing the receiving portion of the pouch-type battery. Therefore, when the central portion of the heat transfer preventing unit 310 is formed to be relatively thick as in this embodiment, it is possible to effectively respond to volume expansion or heat generation occurring in the receiving portion of the pouch unit.

Further, the flame transfer preventing unit 320 may have a groove formed in a concave shape in the central portion. For example, referring to the embodiment of fig. 12, the flame transfer preventing unit 320 is configured to stand in a vertical direction, and a groove may be formed in a central portion between the tip and the distal end, as shown by G2, G2'. In this case, the flame transfer prevention unit 320 may be considered to have an approximately "I" -shaped cross-sectional configuration. In this configuration, the heat transfer preventing unit 310 may also be filled in the central grooves G2, G2' of the flame transfer preventing unit 320. That is, even if the heat transfer preventing unit 310 is configured to entirely cover the left and right surfaces of the flame transfer preventing unit 320, the heat transfer preventing unit 310 may exist more in the central grooves G2, G2' of the flame transfer preventing unit 320.

According to this embodiment of the present disclosure, even though the thickness of the blocking member 300 is not partially changed, a configuration to improve the swelling absorption and thermal insulation performance of the battery cell 100 can be easily achieved by thickening the central portion of the heat transfer prevention unit 310. In particular, the total thickness of the blocking member 300 obtained by summing the thickness of the heat transfer preventing unit 310 and the thickness of the flame transfer preventing unit 320 may be uniform. For example, in the embodiment of fig. 12, even if the thickness of the heat transfer preventing unit 310 is not constant but varies from top to bottom, the total thickness of the blocking member 300 may be uniformly formed from top to bottom. Therefore, when the blocking member 300 is interposed between the battery cells 100, unnecessary space consumption can be prevented, and the battery cells 100 and the blocking member 300 can be well arranged side by side. In addition, according to this embodiment, since at least a portion of the heat transfer preventing unit 310 is inserted into the central grooves G2, G2' of the flame transfer preventing unit 320, the coupling force between the heat transfer preventing unit 310 and the flame transfer preventing unit 320 can be further improved. In particular, according to this embodiment, the heat transfer preventing unit 310 can be restrained from moving in the front, rear, up and down directions of the flame transfer preventing unit 320.

Fig. 13 is a sectional view schematically showing a configuration of a blocking member 300 according to still another embodiment of the present disclosure.

Referring to fig. 13, in the blocking member 300, the flame transfer preventing unit 320 may have concave grooves formed on central portions of left and right surfaces, as shown by G3 and G3', and these grooves may be formed to be curved or inclined. That is, the thickness of the flame transfer preventing unit 320 in the left-right direction (Y-axis direction) may be formed to gradually decrease from the top end toward the center portion, and gradually increase again from the center portion toward the bottom end. Further, the flame transfer preventing unit 320 may be considered to have a groove because the thickness of the center portion is thin as described above. In addition, the grooves G3, G3' formed in the central portion as described above may be filled with the heat transfer preventing unit 310. Accordingly, the heat transfer preventing unit 310 may be formed such that the center portion has a greater thickness than the end portions.

According to this embodiment of the present disclosure, the swelling form of the battery cell 100 can be responded more effectively. In particular, when swelling of the battery cell 100 occurs, the central portion of the battery cell 100 may be maximally swelled, and the degree of swelling may be gradually reduced toward the end portions. According to this embodiment, the heat transfer prevention unit 310 and the flame transfer prevention unit 320 may be considered to be configured to correspond to the expanded shape of the battery cell 100. Thus, the swelling of the battery cell 100 can be responded to more appropriately.

Fig. 14 is a sectional view schematically showing a configuration of a blocking member 300 according to still another embodiment of the present disclosure.

Referring to fig. 14, in the flame transfer preventing unit 320, a groove may be formed in a concave shape in the central portion, and an empty space not filled with the heat transfer preventing unit 310 may be formed in the concave groove of the central portion. For example, as shown by F1 in fig. 14, an empty space, such as an air layer, may exist between the left surface of the flame transfer preventing unit 320 and the left heat transfer preventing unit 310. Further, as shown by F1' in fig. 14, an empty space may be formed between the right surface of the flame transfer preventing unit 320 and the right heat transfer preventing unit 310.

According to this embodiment of the present disclosure, the empty spaces F1, F1' between the flame transfer prevention unit 320 and the heat transfer prevention unit 310 may be used as spaces for absorbing the swelling of the battery cell 100. Further, according to this embodiment, by reducing the weight of the blocking member 300, the weight of the entire battery module can be advantageously reduced.

Fig. 15 is a sectional view schematically showing a configuration of a blocking member 300 according to still another embodiment of the present disclosure.

Referring to fig. 15, the flame transfer preventing unit 320 may be configured to have a thickness gradually increasing or decreasing from one end to the other end. In particular, the flame transfer prevention unit 320 may be configured to have an inclined surface formed on an outer surface. For example, as shown in fig. 15, the flame transfer preventing unit 320 may have inclined surfaces F2, F2' formed such that the thickness gradually decreases in a lower direction (-Z axis direction) from the top.

According to this embodiment of the present disclosure, when a flame occurs inside the battery module, the flame transfer prevention unit 320 may be exposed to the outside, and the exhaust gas or flame may be controlled in the discharge or movement direction of the inclined surfaces F2, F2' formed at the flame transfer prevention unit 320. For example, according to the configuration shown in fig. 15, by the inclined surfaces F2, F2' of the flame transfer preventing unit 320, gas or flame can be caused in the lower direction as much as possible. In particular, the gas or flame may have a property of being directed upward, and according to this embodiment, the gas or flame may be restrained from moving in an upward direction. Thus, by preventing gas or flame from being discharged to the upper side of the battery module, it is possible to more advantageously protect a device or driver located above the battery module.

Fig. 16 is a perspective view schematically showing the configuration of a flame transfer preventing unit 320 provided in a blocking member 300 according to still another embodiment of the present disclosure. In particular, in the configuration of fig. 16, only the form of the flame transfer prevention unit 320 is shown in the blocking member 300, and the heat transfer prevention unit 310 is removed. For example, it can be considered that the embodiment of fig. 16 shows a configuration in which the heat transfer preventing unit 310 is melted and lost due to flame or the like.

Referring to fig. 16, in the flame transfer preventing unit 320, a groove may be formed in a central portion. That is, the flame transfer preventing unit 320 may have grooves recessed toward the inside on the left and right surfaces, respectively, as shown in G4. Further, the flame transfer preventing unit 320 may be configured such that at least one side of the groove G4 is open to the outside. For example, the groove G4 formed on the right surface of the flame transfer preventing unit 320 may be configured to be open at the front side, as shown by H1 in fig. 16. Further, the groove formed on the left surface of the flame transfer preventing unit 320 may be configured to be open at the front side, as in the portion shown as H1' in fig. 16.

According to this embodiment of the present disclosure, exhaust gas may be discharged due to the open portions H1, H1' of the grooves formed at the flame transfer preventing unit 320. For example, as shown in fig. 16, when the open portions H1, H1 'are formed at the front side with respect to the groove G4 of the flame transfer preventing unit 320, exhaust gas introduced into the groove G4 of the flame transfer preventing unit 320 may be discharged to the outside through the front open portions H1, H1'. In this case, the gas may move forward along the surface of the flame transfer prevention unit 320, as indicated by an arrow D2 in fig. 16. Thus, according to this embodiment, it is possible to appropriately control or cause the discharge of exhaust gas in the direction thereof.

In particular, a vent hole (not shown) may be formed in the module case 200 of the battery module. For example, the vent holes may be formed in the front plate 250 of the module case 200. At this time, as shown in fig. 16, when the exhaust gas is guided to the front side through the flame transfer preventing unit 320 of the blocking member 300, the exhaust gas can be smoothly and rapidly discharged into the vent hole. Therefore, when gas is generated inside the battery module due to an abnormal condition such as thermal runaway, explosion of the battery module can be prevented, and safety can be ensured when exhaust gas is discharged.

Fig. 17 is a perspective view schematically showing the configuration of a flame transfer preventing unit 320 provided in a blocking member 300 according to still another embodiment of the present disclosure. In the configuration of fig. 17, similarly to fig. 16, only the form of the flame transfer prevention unit 320 is shown in the blocking member 300, and the heat transfer prevention unit 310 is removed. That is, similar to fig. 16, it can be considered that the embodiment of fig. 17 shows a configuration in which the heat transfer preventing unit 310 is melted and lost due to flame or the like.

Referring to fig. 17, the flame transfer preventing unit 320 has a groove G4 formed in a central portion, similar to fig. 16, and an open portion H1 is formed at one side (e.g., at a front side) such that gas or the like is discharged to the open portion H1. However, in the embodiment of fig. 17, a blocking protrusion configured to protrude outward as shown in P1 is formed in the groove G4 of the flame transfer preventing unit 320. For example, a groove G4 is formed on the right surface of the flame transfer preventing unit 320, and a blocking protrusion P1 protruding in the right direction may be formed in the groove G4.

In the configuration of the flame transfer preventing unit 320, the exhaust gas introduced into the groove G4 is discharged toward the open portion H1 located at the front, and the flow of the exhaust gas may be blocked by the blocking protrusion P1. However, the blocking protrusion P1 does not completely block the exhaust gas from being discharged from the groove G4 toward the open portion H1, but may be configured such that the flow direction of the exhaust gas is curved. For example, as shown in fig. 17, a plurality of blocking protrusions P1 may be formed in the groove G4 of the flame transfer preventing unit 320 such that the exhaust gas is bent upward and/or downward as shown by an arrow D3 when being discharged to the front side. Further, although only the right surface of the flame transfer preventing unit 320 is shown in fig. 17, a groove G4 may be formed on the left surface of the flame transfer preventing unit 320, and a blocking protrusion P1 may be formed in the groove.

In particular, the blocking protrusion P1 may be configured to be elongated in a direction orthogonal to the discharge direction of the gas or the like. For example, referring to fig. 17, regarding the flame transfer preventing unit 320 of the blocking member 300, exhaust gas may be discharged to the front side (-X axis direction) through the groove G4. In this case, the blocking protrusion P1 may be configured to be elongated in a vertical direction (Z-axis direction) orthogonal to the discharge direction of the exhaust gas.

According to the embodiment of the present disclosure, in the course of causing the exhaust gas to pass through the flame transfer preventing unit 320 of the blocking member 300 by extending the exhaust path of the exhaust gas, the temperature of the exhaust gas may be reduced. Further, according to this embodiment, since the curved portion is formed in the exhaust gas discharge path, when the flame is discharged together with the exhaust gas, the flame having strong straightness can be blocked from being discharged to the outside. Further, according to this embodiment, it is possible to suppress spark or active material particles contained in exhaust gas from being discharged to the outside. Therefore, in this case, it is possible to prevent a fire from occurring outside the battery module or in another battery cell 100.

In particular, in this embodiment, the blocking protrusion P1 may be located at the open portion H1 of the flame transfer preventing unit 320. In this case, the problem that the blocking protrusion P1 adversely interferes with the flow of exhaust gas into the groove G4 can be prevented or reduced.

Fig. 18 is a perspective view schematically showing the configuration of a flame transfer preventing unit 320 provided in a blocking member 300 according to still another embodiment of the present disclosure. Further, fig. 19 is a sectional view taken along line A4-A4' of fig. 18. The configurations shown in fig. 18 and 19 may also be regarded as showing a state in which the heat transfer prevention unit 310 is removed.

Referring to fig. 18 and 19, in the grooves formed on both surfaces of the flame transfer preventing unit 320, the open portions may be formed at different sides. More specifically, grooves G4', G4 may be formed on the right and left surfaces of the flame transfer preventing unit 320, respectively, and open portions H1, H1' may be formed at the grooves G4', G4, respectively. In this case, the open portion H1 of the right surface may be formed at the front side of the flame transfer preventing unit 320, and the open portion (H1') of the left surface may be formed at the rear side of the flame transfer preventing unit 320. That is, the open portions formed on both surfaces of the flame transfer preventing unit 320 may be formed at opposite sides.

In this case, the exhaust gas discharged from the battery cell 100 located at the right side of the flame transfer prevention unit 320 may move to the front side (-X axis direction) along the right surface of the flame transfer prevention unit 320, as shown by arrow D4 in fig. 19. In addition, the exhaust gas discharged from the battery cell 100 located at the left side of the flame transfer prevention unit 320 may move to the rear side (+x axis direction) along the left surface of the flame transfer prevention unit 320, as shown by arrow D4' in fig. 19.

According to this embodiment of the present disclosure, the discharge direction of the gas generated from the battery cell 100 disposed at the left side with respect to one blocking member 300 may be different (particularly opposite) from the discharge direction of the gas generated from the battery cell 100 disposed at the right side. Therefore, it is possible to prevent the high-temperature or high-pressure exhaust gas from concentrating on a specific portion.

Further, according to this embodiment, it is possible to more effectively prevent the exhaust gas discharged to one side from flowing toward the battery cell 100 positioned beyond the flame transfer preventing unit. For example, in the embodiment of fig. 18 and 19, when exhaust gas generated from the battery cell 100 located at the right side of the flame transfer preventing unit 320 is discharged toward the right open portion H1 of the flame transfer preventing unit 320, the exhaust gas may be prevented from flowing toward the battery cell 100 located at the left side of the flame transfer preventing unit 320 through the left open portion H1' of the flame transfer preventing unit 320. Therefore, according to this embodiment of the present disclosure, the effect of preventing the thermal runaway transition between the battery cells 100 can be more effectively ensured.

In the battery module according to the present disclosure, each of the plurality of battery cells 100 may be a pouch-type secondary battery as shown in fig. 2 and 3. In this case, each secondary battery may include a receiving portion and a sealing portion.

In this configuration, the flame transfer preventing unit 320 may be formed such that a portion facing the sealing portion has a greater thickness than a portion facing the receiving portion. This will be described in more detail with reference to fig. 20.

Fig. 20 is a diagram schematically showing a partial configuration of a battery module according to an embodiment of the present disclosure when viewed from the top. In fig. 20, only one battery cell 100 and one blocking member 300 are shown for convenience of explanation.

Referring to fig. 20, the battery cell 100 may be a pouch-type secondary battery, and in this case, the battery cell 100 may include a receiving part indicated by J1 and a sealing part indicated by J2. Here, the receiving portion J1 may be a portion that receives the electrode assembly (including the positive electrode plate, the negative electrode plate, and the separator) and the electrolyte in an inner space outside the pouch. In addition, the sealing portion J2 may be located at an edge of the receiving portion J1, and may be a portion sealing an inner space of the receiving portion J1 in a state where the outside of the bag is fused. The configuration of the receiving portion J1 and the sealing portion J2 is well known at the time of filing the present disclosure and will not be described in detail herein.

Corresponding to this type of battery cell 100, in a state in which the flame transfer preventing unit 320 is interposed between the plurality of battery cells 100, a portion facing the receiving portion J1 may have a smaller thickness than a portion facing the sealing portion J2. More specifically, referring to the configuration shown in fig. 20, in the flame transfer preventing unit 320, a portion facing the accommodating portion J1 may be referred to as I1, and a portion facing the sealing portion J2 may be referred to as I2. In this case, in the flame transfer preventing unit 320, the portion indicated by I2 may be formed thicker than the portion indicated by I1. In particular, in a state in which the blocking member 300 is interposed between the pouch type battery cells 100, a portion facing the sealing portion J2 may be an end side of the blocking member, i.e., an end in the front-rear direction. Accordingly, the flame transfer prevention unit 320 may be considered to be formed such that its ends (i.e., front and rear ends and/or upper and lower ends of the sealing portion J2 facing the battery cell 100 when in the form of an upright sheet) are formed thicker than a central portion corresponding to the receiving portion J1 of the battery cell 100.

According to this embodiment of the present disclosure, the flame blocking effect between the pouch type battery cells 100 may be further improved. In particular, when a plurality of pouch type battery cells 100 are stacked side by side, an empty space may be more formed at the sealing part J2 than the receiving part J1. Accordingly, when flame is discharged from a specific battery cell 100, the discharged flame and high temperature gas may be directed toward the sealing portion J2 of the battery cell 100. At this time, in this embodiment, since the flame transfer preventing unit 320 is formed thicker in the sealing portion J2, it is possible to more effectively block the flame located at the sealing portion J2 from propagating toward the other battery cells 100.

In particular, the pouch-type battery cell 100 has a substantially rectangular shape, and the sealing part J2 may be formed at four or three edges surrounding the receiving part J1. At this time, the electrode lead 101 may protrude toward some sealing parts J2 among the several sealing parts J2. For example, in the pouch-type battery cell 100 in the vertically erected form, the sealing portions J2 may be positioned at the front, rear, upper and lower portions, respectively. At this time, as shown in fig. 20, the electrode leads 101 may be disposed to protrude toward the sealing portion at the front side and the sealing portion at the rear side, respectively. At this time, the sealing portion from which the electrode lead 101 protrudes may be referred to as a stepped portion so as to be distinguished from other sealing portions. In this case, the flame transfer preventing unit 320 may be formed such that a portion facing the landing portion has a greater thickness than a portion facing the receiving portion. Further, the thickness of the portion facing the landing portion may be formed to be greater than the thickness of the portion facing the sealing portion other than the landing portion.

According to the embodiment of the present disclosure, the flame blocking effect of the flame transfer prevention unit 320 may be further improved. In particular, since the landing portion may have a larger area than the other sealing portion J2, flame or high-temperature exhaust gas may be more concentrated. Therefore, as in this embodiment, when the portion corresponding to the landing portion has a greater thickness among the respective portions of the flame transfer prevention unit 320, the flame blocking performance between the battery cells 100 can be more stably ensured even when the flame is concentrated on the landing portion. Further, according to this embodiment, the electrode lead may be stably protected from flames due to the thickness difference of the flame transfer preventing unit 320.

In addition, referring to the embodiment of fig. 20, in the heat transfer prevention unit 310, a portion facing the receiving portion J1 of the battery cell 100 may have a greater thickness than a portion facing the sealing portion J2 of the battery cell 100. In this case, even though a relatively large amount of heat or expansion occurs in the receiving portion J1 of the battery cell 100, since the heat transfer preventing unit 310 is formed thicker, the generated heat or volume expansion can be appropriately absorbed.

The blocking member 300 may be disposed not only between the battery cells 100 but also between the battery cells 100 and the module case 200. For example, referring to fig. 2 and 3, when a plurality of battery cells 100 are disposed in the left-right direction (Y-axis direction) to form a cell assembly, blocking members 300 may be disposed at left and right sides of the cell assembly, respectively. In this case, the blocking member 300 may be considered to be disposed between the cell assembly and the module case 200.

According to this embodiment of the present disclosure, when heat or flame is generated inside the battery module, it is possible to block or inhibit the heat or flame from being transferred to the outside of the battery module. In particular, outside the battery module, other battery modules or other components of the battery pack, such as a Battery Management System (BMS), may be provided. According to this embodiment, the transfer of heat or flame to other battery modules or BMSs can be minimized.

Referring to fig. 21, a plurality of pouch-type battery cells 100 may be disposed in the left-right direction (Y-axis direction) in an upright state such that the receiving parts face in the left-right direction. At this time, in each battery cell 100, the electrode leads 101 may protrude in the front-rear direction (X-axis direction). The blocking member 300 may be disposed along the stacking direction (Y-axis direction) of the plurality of battery cells 100. In particular, some of the plurality of blocking members 300 may be positioned outside the cell stack and other blocking members may be positioned inside the cell stack. More specifically, in the embodiment of fig. 21, as shown in K1 to K5, five blocking members 300 may be provided to be spaced apart from each other in the left-right direction. Here, the first and fifth members K1 and K5 are disposed at the left and right sides of the outermost sides of the cell stack, and the second, third and fourth members K2, K3 and K4 are disposed inside the cell stack.

In this embodiment, two or more of the plurality of blocking members 300 may be configured to have different compression ratios. For example, in the embodiment of fig. 21, two or more of the five blocking members 300 indicated by K1 to K5 may be configured to have different compression ratios. Here, the compression ratio may represent a degree of compression when pressure is applied in the thickness direction. For example, when pressure is applied to the outer surface, the compression ratio of each blocking member 300 may represent the degree to which the thickness is reduced in the Y-axis direction, as shown by D1 in the embodiment of fig. 11. Thus, a high compression ratio may indicate that a relatively greater compression may be achieved when the same force is applied.

In particular, the plurality of blocking members 300 may be configured to have a difference in compression ratio between the blocking members 300 disposed outside the cell stack and the blocking members 300 disposed inside the cell stack. Further, the outer barrier member 300 may be configured to have a lower compression ratio than the inner barrier member 300. For example, in the embodiment of fig. 21, the first member K1 and the fifth member K5 disposed outside the cell stack may have a lower compression ratio than the second member K2, the third member K3, and the fourth member K4 disposed inside the cell stack.

According to this embodiment, when the swelling occurs in the battery cells 100 included in the cell stack, the problem of damaging the battery cells 100 can be more effectively prevented while ensuring the capability of coping with the swelling. That is, the inner resistance members such as the second member K2 to the fourth member K4 can absorb the bulge of the cell stack well due to the relatively high compression ratio. Meanwhile, the outer blocking members, such as the first member K1 and the fifth member K5, may restrain excessive movement of the outermost battery cells 100 due to a relatively low compression ratio.

In particular, at least one side of the cell stack (e.g., the bottom end of each battery cell 100) may be adhered and fixed to the module case 200 by an adhesive. For example, in the embodiment of fig. 21, a thermal resin may be interposed as an adhesive between the lower portion of the cell stack and the upper surface of the lower plate 220. Furthermore, the outermost battery cell 100 can move the most when the swelling occurs in the plurality of battery cells 100 belonging to the cell stack. At this time, if the moving distance of the outermost unit becomes longer in a state in which the lower end is adhesively fixed, the possibility that the battery cell 100 is torn is great.

However, according to this embodiment, excessive movement of the outermost battery cells 100 can be suppressed by a low compression ratio of the outer barrier members such as K1 and K5. Furthermore, the bulge of the cell stack can be absorbed well by the blocking members 300, such as K2 to K4, which are positioned relatively inner. Thus, the tearing problem of the outermost battery cells 100 can be prevented. In addition, in this case, since the thickness of the outermost blocking member 300 can be configured to be thin, an effect of widening the inner space of the module case 200 can also be obtained. Therefore, this also contributes to an improvement in the energy density of the battery module.

As described above, representative embodiments in which the blocking member 300 has different compression ratios will be described in more detail with reference to fig. 22 and 23.

Fig. 22 and 23 are enlarged views illustrating the configuration of different blocking members 300 included in the battery module of fig. 21. Specifically, fig. 22 may be an enlarged front view illustrating a portion a61 of fig. 21, and fig. 23 may be an enlarged front view illustrating a portion a63 of fig. 21.

Referring to fig. 22 and 23, the plurality of blocking members 300 may be configured to have different thicknesses. For example, in the embodiment of fig. 21, the outermost barrier member K1 may be configured to have a thickness as indicated by T1 in fig. 22, and the inner barrier member K3 may be configured to have a thickness as indicated by T3 in fig. 23. In this case, the thickness T1 of the outermost barrier member K1 may be thinner than the thickness T3 of the inner barrier member K3. That is, T1 and T3 may have a relationship of T1< T3. Here, the two outermost barrier members K1, K5 may have the same thickness, and the three inner barrier members K2, K3, K4 may have the same thickness.

Alternatively, when a plurality of inner blocking members are provided, the plurality of inner blocking members may be configured to have different thicknesses. For example, in the embodiment of fig. 21, among the three inner resistance members K2, K3, K4, the inner resistance member K3 located at the center may be configured to have a larger thickness than the other two inner resistance members K2, K4 located relatively outside. In this case, it can be considered that the thickness of the blocking member 300 increases sequentially from the outside to the inside of the cell stack.

Further, among the plurality of blocking members 300, the heat transfer preventing unit 310 may mainly function to absorb the swelling. Accordingly, among the plurality of blocking members 300, the heat transfer preventing unit 310 may be configured to have different thicknesses. In particular, the heat transfer preventing unit 310 of the blocking member positioned at the outside may have a smaller thickness than the heat transfer preventing unit 310 of the blocking member positioned at the inside.

For example, the heat transfer preventing unit 310 of the outermost barrier member K1 may have a thickness as indicated by T11 in fig. 22, and the heat transfer preventing unit 310 of the inner barrier member K3 may have a thickness as indicated by T31 in fig. 23. At this time, T11 and T31 may be set to have a relationship of T11 < T31. That is, the thickness T31 of the heat transfer preventing unit 310 of the outermost barrier member K1 may be thinner than the thickness T31 of the heat transfer preventing unit 310 of the inner barrier member K3. In this case, the total thickness T1 of the outermost barrier member K1 may be thinner than the total thickness T3 of the inner barrier member K3.

According to this embodiment, since the heat transfer preventing unit 310 of the outermost barrier member is formed to be relatively thin, the effect of restricting the movement of the outermost battery cell 100 can be enhanced. Therefore, the tearing phenomenon of the outermost battery cells 100 due to excessive movement can be effectively prevented.

Further, the flame transfer preventing unit 320 of the outermost barrier member K1 may have a thickness indicated by T12 in fig. 22, and the flame transfer preventing unit 320 of the inner barrier member K3 may have a thickness indicated by T32 in fig. 23. At this time, T12 and T32 may be set to have a relationship of T12 > T32. That is, the thickness T32 of the flame transfer preventing unit 320 of the outermost barrier member K1 may be thicker than the thickness T32 of the flame transfer preventing unit 320 of the inner barrier member K3. Further, in the outermost barrier member K1, the flame transfer preventing unit 320 may be formed to be relatively thick, and the heat transfer preventing unit 310 may be formed to be relatively thin, as compared to the inner barrier member K3. Since the flame transfer prevention unit 320 may have higher rigidity than the heat transfer prevention unit 310, the performance of suppressing pushing of the outermost battery cell 100 may be better ensured according to the embodiment. Further, in this case, the outermost barrier member K1 and the inner barrier member K3 may have the same thickness, or the thickness difference may be not large.

Furthermore, the blocking member 300 may be interposed between different cell groups. This will be described in more detail with reference to fig. 24 and 25.

Fig. 24 is an exploded perspective view illustrating a battery module according to still another embodiment of the present disclosure. Fig. 25 is a sectional view of the battery module of fig. 24. With respect to this embodiment, features different from the foregoing embodiment will be described in detail.

Referring to fig. 24 and 25, a plurality of battery cells 100 included in a battery module may be grouped into several cell groups, as indicated by CB1 to CB 8. Further, a plurality of cell groups CB1 to CB8 may be connected to each other in series. That is, the plurality of battery cells 100 may include two or more cell groups connected in series.

Further, a plurality of battery cells 100 may be included in each of the cell groups CB1 to CB 8. At this time, the battery cells 100 in each cell group may be connected in parallel with each other. For example, in the embodiments of fig. 24 and 25, each cell group may include three battery cells 100 connected in parallel.

In this embodiment, the blocking member 300 may be interposed between different cell groups. For example, as shown in fig. 24 and 25, when eight cell groups CB1 to CB8 are included in the battery module, the blocking members 300 may be interposed between different cell groups, respectively.

According to this embodiment, even if thermal runaway or the like occurs inside some of the cell groups, it is possible to prevent or suppress propagation of thermal runaway to other cell groups connected in series. Therefore, even if voltage drop of the battery module occurs due to gas discharge or ignition of a specific cell stack, the voltage drop may occur stepwise in the cell stack unit. Therefore, it is possible to obtain an effect of delaying the voltage drop as much as possible by reducing the voltage drop rate of the entire battery module.

In addition, in this case, the safety of the battery module or the device to which the battery module is applied may be improved. For example, even if a situation such as thermal runaway occurs in a battery module mounted in an electric vehicle or the like, the voltage drop may be performed as slowly as possible. Thus, the driver can continuously drive the electric vehicle for a certain period of time and move it to a safe point such as a road shoulder as much as possible.

In order to increase the energy density of the battery module and to ensure stability even in the presence of swelling or vibration, it is necessary to appropriately design the size of the components or spaces included in a given space within the module case 200.

In the case of the battery module according to the present disclosure, a stacking unit formed by stacking a plurality of components may be accommodated in the inner space of the module case 200. Here, the stacking unit may include the battery cell 100 and the blocking member 300. In particular, the blocking member 300 may be disposed outside the space between the battery cells 100 and/or in the space between the battery cells 100. Further, an adhesive member may be interposed in the stacking unit to fix various components. For example, an adhesive member may be positioned between two battery cells 100 and/or between a battery cell 100 and a blocking member 300 to bring different components into close contact. Here, the adhesive member may be configured such that an adhesive is applied using a spraying method or the like, or may be configured such that an adhesive sheet or an adhesive pad is attached to the unit surface. In particular, even if the adhesive is applied by spraying or the like, the adhesive member can be prepared in the form of a sheet or a pad having a certain thickness when the adhesive is cured.

In this embodiment, the total width of the stacked unit may be calculated by the following formula. In this case, the width may represent the total length of the stacking unit set in the direction in which the plurality of battery cells 100 are stacked (for example, the Y-axis direction of fig. 24), and may have units of mm or the like.

W _T ＝W _C +W _O +W _I +W _A

Here, W is _T Can represent the entire width of the stacked unit, W _C Can represent the total thickness of all battery cells, W _O Can represent the entire width of the outermost pad, and W _I The entire width of the inner pad may be represented. At this time, the outermost pad is the outermost blocking member 300, such as K1 or K5 in fig. 21, and the inner pad is the inner blocking member 300 located inside the cell stack, i.e., between the battery cells 100, as shown by K2 to K4 in fig. 21. In addition, W _A The entire width of the adhesive member may be represented. W (W) _O 、W _I 、W _A Etc. may have units of length such as mm etc.

In the equation, W _C The derivation can be achieved as follows: battery cell (N) _C ) Is multiplied by the total number of each battery cell thickness (T _C )。

W _C ＝N _C *T _C

In addition, W _O The number of outermost pads (N can be used as follows _O ) Thickness of each outermost pad (T _O ) Initial compression ratio of outermost pad (C _O ) To calculate.

W _O ＝N _O *(T _O *(1-C _O ))

Here, the initial compression ratio (C _O ) The compression ratio of the outermost pad in a state in which no bulge occurs in the battery cells after the stack unit is inserted and assembled into the module case may be represented. That is, the initial compression ratio (C _O ) The initial compression degree of the outermost pad when the battery module is assembled may be expressed. For example, if the outermost pad is compressed 15% compared to the state before pressing when inserting the stacked unit into the inside of the module case, the initial compression ratio (C _O ) May be 0.15.

In addition, W _I The number of internal pads (N _I ) Thickness of each inner pad (T _I ) Initial compression ratio of inner pad (C _I ) The calculation is as follows.

W _I ＝N _I *(T _I *(1-C _I ))

Here, the initial compression ratio (C _I ) The compression ratio of the inner mat in a state in which no swelling occurs in the battery cells after the stack unit is inserted and assembled into the module case may be represented. That is, the initial compression ratio (C _I ) May represent the degree to which the internal mat is compressed when the battery module is initially assembled. For example, if the inner pad is compressed 20% compared to the state before pressurization when the stacked unit is inserted into the inside of the module case, the initial compression ratio (C _I ) May be 0.2.

In addition, W _A The number of adhesive members (N _A ) And the thickness (T) _A ) The calculation is as follows.

W _A ＝N _A *T _A

At the same time, the initial compression ratio of the blocking member, i.e., the initial compression ratio of the outermost pad (C _O ) And/or the initial compression ratio (C) _I ) To an appropriate degree. In particular, the initial compression ratio of the blocking member may be set to 8% or more, further 10% or more, particularly 12% or more. Further, the initial compression ratio of the blocking member may be set to 22% or less, further 20% or less, particularly 18% or less. For example, the initial compression ratio of the blocking member may be set to 10% to 20%. When the initial compression ratio of the blocking member is set When smaller than this range, the movement of the stacked unit inside the module case may increase due to tolerances or the like, and structural stability may deteriorate. Meanwhile, if the initial compression ratio of the blocking member exceeds the range, it is difficult to insert the stacked unit into the module case. Accordingly, by appropriately setting the initial compression ratio of the blocking member as described above, the assembly and/or structural stability of the battery module may be further improved.

A battery pack according to the present disclosure may include one or more battery modules according to the present disclosure as described above. Further, the battery pack according to the present disclosure may further include various components other than the battery modules, for example, components of the battery pack known at the time of filing the present application, such as a BMS or a bus bar, a battery pack case, a relay, and a current sensor. Further, in the battery pack according to the present disclosure, the above-described module case 200 may be used as a battery pack case. In this case, components of the battery pack, such as a BMS, bus bars, and relays, may be included in the module case 200. In this case, the battery cell 100 is also referred to as a cell-to-Cell (CTP) because it is directly stored in the battery pack case.

The battery module according to the present disclosure may be applied to a vehicle such as an electric vehicle or a hybrid electric vehicle. That is, a vehicle according to the present disclosure may include a battery module according to the present disclosure or a battery pack according to the present disclosure. Further, the vehicle according to the present disclosure 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 disclosure may further include a vehicle body, a motor, a control device such as an Electronic Control Unit (ECU), and the like, in addition to the battery module according to the present disclosure.

Meanwhile, in the present specification, terms indicating directions such as "upper", "lower", "left", "right", "front" and "rear" are used, but these terms are merely for convenience of description and may be changed according to the position of an object or the position of an observer, as will be apparent to those skilled in the art.

The present disclosure has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the scope of the disclosure will become apparent to those skilled in the art from this detailed description.

[ reference numerals ]

100: battery cell

200: module shell

210: upper plate, 220: lower plate, 230: left panel, 240: right panel, 250: front plate, 260: rear plate

300: barrier member

310: heat transfer prevention unit, 320: flame transfer prevention unit

Claims

1. A battery module, the battery module comprising:

a plurality of battery cells stacked in at least one direction;

a module housing configured to accommodate the plurality of battery cells in an interior space of the module housing; and

a blocking member interposed between adjacent battery cells and including a heat transfer prevention unit configured to prevent heat transfer between the adjacent battery cells and a flame transfer prevention unit disposed inside the heat transfer prevention unit and configured to block flames between the adjacent battery cells.

2. The battery module according to claim 1,

wherein the heat transfer prevention unit is made of a material having a lower thermal conductivity than the flame transfer prevention unit.

3. The battery module according to claim 1,

Wherein the flame transfer prevention unit is made of a material having a higher melting point than the heat transfer prevention unit.

4. The battery module according to claim 1,

wherein the blocking member is configured to expose the flame transfer prevention unit toward the battery cell when the heat transfer prevention unit is melted.

5. The battery module according to claim 1,

wherein the blocking member is configured in sheet form.

6. The battery module according to claim 1,

wherein the blocking member is configured such that the flame transfer preventing sheet is interposed inside the heat transfer preventing sheet.

7. The battery module according to claim 1,

wherein the blocking member is configured to absorb the bulge of the battery cell.

8. The battery module according to claim 1,

wherein the heat transfer preventing unit is formed such that its center has a greater thickness than its ends.

9. The battery module according to claim 1,

wherein the flame transfer prevention unit has a groove formed in a concave shape in a central portion thereof.

10. The battery module according to claim 9,

wherein the flame transfer prevention unit is configured such that at least one side of the groove formed in the central portion is open to the outside.

11. The battery module according to claim 1,

wherein each of the plurality of battery cells is a pouch-type secondary battery having a receiving portion and a sealing portion, and

the flame transfer prevention unit is formed such that a portion facing the sealing portion between the plurality of battery cells has a greater thickness than a portion facing the receiving portion.

12. The battery module according to claim 1,

wherein the blocking members are arranged in a stacking direction of the plurality of battery cells as a plurality of blocking members, and

two or more of the plurality of blocking members are configured to have different compression ratios.

13. The battery module according to claim 1,

wherein the plurality of battery cells comprises two or more cell groups connected in series, an

The blocking member is interposed between different cell groups.

14. A battery pack comprising the battery module according to any one of claims 1 to 13.

15. A vehicle comprising the battery module according to any one of claims 1 to 13.