Patent Description:
Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries, wherein compared to nickel-based secondary batteries, the lithium secondary batteries have little memory effect, and thus, are attracting attention because of their advantages such as free charge and discharge, extremely low self-discharge rate, and high energy density.

The lithium secondary batteries use a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. Lithium secondary batteries includes an electrode assembly in which a positive electrode plate and a negative electrode plate, to which a positive electrode active material and a negative electrode active material are applied, respectively, are arranged with a separator therebetween, respectively, and a packaging material for sealing and accommodating the electrode assembly together with an electrolyte, that is, a battery pouch packaging material.

Recently, secondary batteries have been widely used not only in small devices such as portable electronic devices, but also in medium and large devices such as vehicles or power storage devices. When used in the medium and large devices, a number of secondary batteries are electrically connected to each other to increase capacity and output. Especially, pouch-type secondary batteries are widely used in the medium and large devices due to an advantage of easy stacking.

Meanwhile, as a need for a large-capacity structure, including application as an energy storage source, increases, a demand for a battery module including a plurality of secondary batteries electrically connected in series and/or parallel and a module housing accommodating the secondary batteries therein is increasing.

However, in battery modules of the related art, when some of a plurality of secondary batteries provided therein are ignited or exploded, heat or fire is propagated between the plurality of secondary batteries, and the flame may melt and make a hole in a portion of a battery module. In some cases, through the punctured portion, the flame is erupted to the outside of the battery module such that the fire is transferred to another neighboring battery module, or outside air is introduced into the battery module to help combustion, leading to a bigger fire or a secondary explosion.

Furthermore, in the battery modules of the related art, an electrical short circuit or spark may be discharged through a hole made by a fire. There is a risk of a fire in another battery module adjacent to the battery module or other structures due to the discharged spark. Especially, when a housing structure for accommodating the battery module is made of iron, high current may flow to another battery module through the housing structure, and thus, gas insulation breakdown (spark) occurs between components of another battery module such that a secondary fire or secondary explosion may occur.

Examples of background art can be found in <CIT>, and <CIT>.

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing a battery module capable of preventing a fire from increasing in size and preventing electrical short circuits due to dew condensation in case of a fire.

Other objects and advantages of the present disclosure may be understood from the following description and will become more fully apparent from embodiments of the present disclosure. Also, it will be easily understood that the objects and advantages of the present disclosure may be realized by the means shown in the appended claims.

A battery module according to the independent claim <NUM> for achieving the object includes:.

The cover portion and the at least one of the upper wall, the lower wall, the left wall, and the right wall of the front cover form a double layer.

Also, the front cover may further include:.

Furthermore, the first cover portion may include a main body portion so as to be in close contact with at least two of an upper surface, a lower surface, a left surface, and a right surface of the upper duct, and a bent portion which is bent and extends from the main body portion, and
the second cover portion may include a main body portion so as to be in close contact with at least two of an upper surface, a lower surface, a left surface, and a right surface of the lower duct, and a bent portion which is bent and extends from the main body portion.

Also, the module case may further include:.

Furthermore, the first insulating plate may include a first protection portion protruding and extending from an end portion to face the inner surface of the upper duct, and
the second insulating plate may include a second protection portion protruding and extending from an end portion to face the inner surface of the lower duct.

Also, each of the first insulating plate and the second insulating plate may further include
a sealing member configured to expand in volume at a predetermined temperature or more to seal the duct in each of the first protection portion and the second protection portion.

Furthermore, each of the first insulating plate and the second insulating plate may include
a partition wall portion that is bent from an outer peripheral end portion toward the battery cell assembly and extends along an outer peripheral portion.

Also, the second insulating plate may have an at least partially inclined surface.

Furthermore, a discharge port configured to discharge a fluid flowing along the inclined surface to the outside may be further included.

Also, a battery rack according to the present disclosure for achieving the object as described above includes at least one battery module.

Also, a power storage device according to the present disclosure for achieving the object as described above includes at least one battery module.

According to one aspect of the present disclosure, the present disclosure includes a cover portion in a module case, and thus, when a fire occurs inside the battery module, a double layer is formed by the cover portion facing at least one of an upper wall, a lower wall, a left wall, and a right wall of a front cover, thereby preventing a hole from being made by the fire in at least one of the upper wall, the lower wall, the left wall, and the right wall of the front cover. Accordingly, the battery module of the present disclosure may significantly increase the safety against a fire.

Also, according to one aspect of an embodiment of the present disclosure, the present disclosure further includes a first insulating plate and a second insulating plate, and thus, in a case where dew condensation occurs due to a temperature difference between the inside and the outside of the module case during use of the module case, water formed by the dew condensation may be prevented from forming a current carrying path between an upper plate or a lower plate and a battery cell assembly. That is, even when water is accumulated in the module case, the water is accumulated in an inner surface of the first insulating plate or the second insulating plate, thereby preventing the water from being in contact with the upper plate and the lower plate. Accordingly, it is possible to effectively prevent the occurrence of an electric leakage, electric short circuit, or the like due to a dew condensation phenomenon of the battery module.

Therefore, the description proposed herein is just a preferable example for the purpose of illustrations only, not intended to limit the scope of the disclosure, so it should be understood that scope of patent protection is defined by the appended claims.

<FIG> is a schematic perspective view showing a battery module according to an embodiment of the present disclosure. <FIG> is a schematic exploded perspective view showing a state in which components of a battery module according to an embodiment of the present disclosure are separated. Also, <FIG> is a schematic perspective view showing a state of a battery cell assembly of a battery module according to an embodiment of the present disclosure. For reference, a front-rear direction is represented as a Y direction, a left-right direction is represented as an X direction, and an up-down direction is represented as a Z direction.

Referring to <FIG>, a battery module <NUM> of the present disclosure includes a battery cell assembly <NUM> having a plurality of battery cells <NUM>, a front cover <NUM>, and a module case <NUM>.

Here, the battery cell assembly <NUM> includes the plurality of battery cells <NUM> stacked on each other in the front-rear direction. As shown in <FIG>, the battery cell assembly <NUM> may include six pouch battery cells <NUM>. As shown in <FIG>, the battery module <NUM> may include seven battery cell assemblies <NUM>.

The battery cell <NUM> may be a pouch-type battery cell <NUM>. For example, as shown in <FIG>, the battery cell assembly <NUM> may be configured in a form in which a plurality of pouch-type battery cells <NUM> are stacked on each other side by side in the front-rear direction (Y direction). Especially, the pouch-type battery cell <NUM> may include an electrode assembly (not shown), an electrolyte (not shown), and a pouch 111c.

Furthermore, as shown in <FIG>, a positive electrode lead 111a and a negative electrode lead 111b may be formed at opposite end portions of the battery cell <NUM> in the left-right direction (X direction) with respect to the center of the battery cell <NUM>. That is, the positive electrode lead 111a may be provided at one end portion with respect to the center of the battery cell <NUM>. Also, the negative electrode lead 111b may be provided at the other end portion with respect to the center of the battery cell <NUM>.

However, the battery module <NUM> according to the present disclosure is not limited to the pouch-type battery cell <NUM> described above, and various battery cells <NUM> known at the time of filing of the present application may be employed.

In the battery module <NUM> according to the present disclosure, a bus bar (not shown) electrically connecting the plurality of battery cells <NUM> may be provided at each of left and right portions of the battery cell assembly <NUM>. The bus bar may include a metal, for example, aluminum, copper, or nickel. The bus bar may be configured to contact the positive electrode lead 111a or the negative electrode lead 111b of each of the plurality of battery cells <NUM>.

Meanwhile, the module case <NUM> has an inner space to accommodate the battery cell assembly <NUM> therein. In detail, the module case <NUM> may include an upper plate <NUM>, a lower plate <NUM>, a front plate <NUM>, and a rear plate <NUM>. Each of the upper plate <NUM>, the lower plate <NUM>, the front plate <NUM>, and the rear plate <NUM> may include steel, an aluminum alloy, or a stainless steel material.

In detail, the lower plate <NUM> may have an area greater than a size of a lower surface of at least one battery cell assembly <NUM> to mount the at least one battery cell assembly <NUM> thereon. The lower plate <NUM> may have a plate shape extending in a horizontal direction.

Also, the upper plate <NUM> may include a top portion 121a and a side portion 121b. The top portion 121a may have a plate shape extending in the horizontal direction to cover an upper portion of the battery cell assembly <NUM>. The side portion 121b may have a plate shape extending downward from both end portions of the top portion 121a in the left-right direction to cover both side portions of the battery cell assembly <NUM> in the left-right direction.

Also, the side portion 121b may be coupled to a portion of the lower plate <NUM>. For example, as shown in <FIG>, the upper plate <NUM> may include the top portion 121a having a plate shape extending in the front-rear and left-right directions.

Furthermore, the upper plate <NUM> may include two side portions 121b extending downward from each of both side portions of the top portion 121a in the left-right direction. Furthermore, a lower end portion of each of the two side portions 121b may be configured to be coupled to both end portions of the lower plate <NUM> in the left-right direction. In this case, a coupling method may be a male-female coupling method or a welding coupling method.

Furthermore, the front plate <NUM> may be configured to cover the front of the battery cell assembly <NUM>. For example, the front plate <NUM> may have a plate shape having a size greater than a size of a front surface of the battery cell <NUM>. The plate shape may be erected in the up-down direction.

Furthermore, a portion of the outer peripheral portion of the front plate <NUM> may be coupled to the lower plate <NUM>. For example, a lower portion of the outer peripheral portion of the front plate <NUM> may be coupled to a front end portion of the lower plate <NUM>. Furthermore, an upper portion of the outer peripheral portion of the front plate <NUM> may be coupled to a front end portion of the upper plate <NUM>. Here, bolt coupling may be employed as a coupling method.

Also, the rear plate <NUM> may be configured to cover the rear of the battery cell assembly <NUM>. For example, the rear plate <NUM> may have a plate shape having a size greater than a size of a rear surface of the battery cell <NUM>.

Also, a portion of the outer peripheral portion of the rear plate <NUM> may be coupled to the lower plate <NUM>. For example, a lower portion of the outer peripheral portion of the rear plate <NUM> may be coupled to a front end portion of the lower plate <NUM>. Furthermore, an upper portion of the outer peripheral portion of the rear plate <NUM> may be coupled to a rear end portion of the upper plate <NUM>. Here, bolt coupling may be employed as a coupling method. A discharge hole formed to allow outside air to flow in or to discharge inside air to the outside may be formed in the rear plate <NUM>.

Furthermore, the module case <NUM> may include steel having excellent mechanical rigidity or a stainless steel material.

<FIG> is a schematic rear perspective view showing a state of a front cover of a battery module according to an embodiment of the present disclosure.

Referring back to <FIG> and <FIG>, the front cover <NUM> may include an upper wall 140a, a lower wall 140b, a left wall 140c, and a right wall 140d, which form an inner space. The front cover <NUM> may be coupled to a front end portion of the module case <NUM>. For example, as shown in <FIG>, the front cover <NUM> may be coupled to the front plate <NUM> of the module case <NUM>.

Furthermore, the front cover <NUM> may include a material of electrical insulation. For example, the front cover <NUM> may include a polyvinyl chloride material.

Also, the module case <NUM> includes a cover portion <NUM> that has a portion protruding to face at least one of the upper wall 140a, the lower wall 140b, the left wall 140c, and the right wall 140d. For example, as shown in <FIG>, when the Y direction is viewed as the front-rear direction, two first cover portions 125a protruding toward the front cover <NUM> may be provided on a front end surface of the upper plate <NUM> of the module case <NUM>. Two second cover portions 125b protruding toward the front cover <NUM> may be provided on a front end surface of the lower plate <NUM>.

Therefore, according to this configuration of the present disclosure, the present disclosure includes a cover portion <NUM>, and thus, when a fire occurs in the battery module <NUM>, a double layer is formed by the cover portion <NUM> facing at least one of the upper wall 140a, the lower wall 140b, the left wall 140c, and the right wall 140d of the front cover <NUM>, thereby preventing a hole from being made by the fire in at least one of the upper wall 140a, the lower wall 140b, the left wall 140c, and the right wall 140d of the front cover <NUM>. Accordingly, the present disclosure may significantly increase the safety against a fire.

<FIG> is a schematic partial vertical cross-sectional view showing an internal state taken along line C-C' of the battery module of <FIG>.

Referring to <FIG> together with <FIG> and <FIG>, the front cover <NUM> of the battery module <NUM> according to an embodiment of the present disclosure may include an upper duct <NUM> and a lower duct <NUM>. The upper duct <NUM> may be formed on an upper end of the front cover <NUM>, and may be configured in such a manner that outside air is introduced into the module case <NUM>. Also, the upper duct <NUM> may have a rectangular tube shape in which a portion of the rectangular tube extends in the front-rear direction. A ceiling inside the upper duct <NUM> may be the upper wall 140a of the front cover <NUM>.

Also, the lower duct <NUM> may be formed on a lower end of the front cover <NUM>, and may be configured in such a manner that outside air is introduced into the module case <NUM>. Also, the lower duct <NUM> may have a rectangular tube shape in which a portion of the rectangular tube extends in the front-rear direction. A bottom inside the lower duct <NUM> may be the lower wall 140b of the front cover <NUM>.

Furthermore, the module case <NUM> may include the upper plate <NUM> located on the battery cell assembly <NUM>, and the lower plate <NUM> located below the battery cell assembly <NUM>. The upper plate <NUM> may include the first cover portion 125a. The first cover portion 125a may protrude and extend from an end portion of the upper plate to face an inner surface of the upper duct <NUM>. For example, as shown in <FIG>, the first cover portion 125a may be configured to face a ceiling (upper wall) 141a inside the upper duct <NUM>.

Also, the lower plate <NUM> may include the second cover portion 125b. The second cover portion 125b may protrude and extend from an end portion of the lower plate to face an inner surface of the lower duct <NUM>. For example, as shown in <FIG>, the second cover portion 125b may be configured to face a bottom (lower wall) 142b inside the lower duct <NUM>.

Furthermore, the upper duct <NUM> and the lower duct <NUM> may each be configured to communicate with a blowing fan <NUM>. The blowing fan <NUM> may be configured to transmit outside air into the module case <NUM>.

Also, the front cover may include an external terminal (not shown) for electrical connection between the battery module <NUM> and an external device, and a single cover <NUM> accommodating the external terminal.

Therefore, according to this configuration of the present disclosure, the present disclosure includes the first cover portion 125a and the second cover portion 125b respectively configured to face inner surfaces of the upper duct <NUM> and the lower duct <NUM> of the front cover <NUM>, and thus, when a fire occurs in the battery module <NUM>, a double layer may be formed by the first cover portion 125a or the second cover portion 125b, thereby preventing a hole from being made by the fire in the inner surfaces of the upper duct <NUM> and the lower duct <NUM> of the front cover <NUM>. Accordingly, the present disclosure may significantly increase the safety against a fire.

<FIG> is a schematic perspective view of an upper plate of a battery module according to another embodiment of the present disclosure.

Referring to <FIG>, the upper plate <NUM> of the battery module <NUM> according to another embodiment of the present disclosure may further include a bent portion 125a2 when compared with the upper plate <NUM> of <FIG>. Other than that, remaining configurations may be the same.

In detail, the first cover portion 125a of the upper plate <NUM> may be configured to be in close contact with at least two of an upper surface, a lower surface, a left surface, and a right surface of the upper duct <NUM>. For example, the first cover portion 125a may include a main body portion 125a1 and the bent portion 125a2. The main body portion 125a1 may be configured to be in close contact with the upper surface of the upper duct <NUM>. The bent portion 125a2 may be configured to be in close contact with the left surface or the right surface of the upper duct <NUM>. The main body portion 125a1 may have a plate shape protruding toward the upper duct <NUM>. The bent portion 125a2 may be bent downward from a left end or a right end of the main body portion 125a1, and may have a shape extending downward.

Also, although not shown, the second cover portion 125b of the lower plate <NUM> may also include a main body portion and a bent portion, which face the inner surface of the lower duct <NUM>, as the first cover portion 125a of the upper plate <NUM>.

Therefore, according to this configuration of the present disclosure, the present disclosure includes the main body portion 125a1 and the bent portion 125a2 respectively in the first cover portion 125a and the second cover portion 125b, and thus, when a fire occurs in the battery module <NUM>, due to the first cover portion 125a or the second cover portion 125b, a hole may be prevented from being made by the fire in at least two of upper surfaces, lower surfaces, left surfaces, and right surfaces of the upper duct <NUM> and the lower duct <NUM>. Accordingly, the present disclosure may significantly increase the safety against a fire.

Meanwhile, referring back to <FIG>, the module case <NUM> may further include a first insulating plate <NUM> and a second insulating plate <NUM>. The first insulating plate <NUM> and the second insulating plate <NUM> may have electrical insulation. For example, the first insulating plate <NUM> may include polyethylene terephthalate, polyvinyl chloride, or silicon material.

Also, the first insulating plate <NUM> may be interposed between the upper plate <NUM> and the battery cell assembly <NUM>. The first insulating plate <NUM> may have a shape extending in a horizontal direction to cover an upper surface of the battery cell assembly <NUM>. The first insulating plate <NUM> may have a size corresponding to the upper surface of the battery cell assembly <NUM>.

Furthermore, the second insulating plate <NUM> may be interposed between the lower plate <NUM> and the battery cell assembly <NUM>. The second insulating plate <NUM> may have a shape extending in a horizontal direction to cover a lower surface of the battery cell assembly <NUM>. The second insulating plate <NUM> may have a size corresponding to the lower surface of the battery cell assembly <NUM>.

Therefore, according to this configuration of the present disclosure, the present disclosure further includes the first insulating plate <NUM> and the second insulating plate <NUM>, and thus, in a case where dew condensation occurs due to a temperature difference between the inside and the outside of the module case <NUM> during use of the module case <NUM>, water formed by the dew condensation may prevent formation of a current carrying path between the upper plate <NUM> or the lower plate <NUM> and the battery cell assembly <NUM>. That is, even when water accumulates inside the module case <NUM>, the water is accommodated in an inner surface of the first insulating plate <NUM> or the second insulating plate <NUM>, thereby preventing the water from being in contact with the upper plate <NUM> or the lower plate <NUM>. Accordingly, it is possible to effectively prevent the occurrence of an electric leakage, electric short circuit, or the like due to a dew condensation phenomenon of the battery module <NUM>.

Meanwhile, referring back to <FIG> and <FIG>, the first insulating plate <NUM> of the present disclosure may include a first protection portion 133a. The first protection portion 133a may have a shape protruding and extending from an end portion of the first insulating plate to face the inner surface of the upper duct <NUM>. The first protection portion 133a may be configured to face an inner ceiling surface of the upper duct <NUM>. The first protection portion 133a may be located below the first cover portion 125a as shown in <FIG>. That is, the first protection portion 133a may form a three-layer structure together with the upper wall 140a of the front cover <NUM> and the first cover portion 125a.

Also, the second insulating plate <NUM> of the present disclosure may include a second protection portion 133b. The second protection portion 133b may have a shape protruding and extending from an end portion of the second insulating plate to face the inner surface of the lower duct <NUM>. The second protection portion 133b may be configured to face an inner bottom surface of the lower duct <NUM>. The second protection portion 133b may be located on the second cover portion 125b as shown in <FIG>. That is, the second protection portion 133b may form a three-layer structure together with the lower wall 140b of the front cover <NUM> and the second cover portion 125b.

Therefore, according to this configuration of the present disclosure, the present disclosure includes the first protection portion 133a and the second protection portion 133b respectively in the first insulating plate <NUM> and the second insulating plate <NUM>, thereby forming a wall of a three-layer structure, and when a fire occur in the battery module <NUM>, due to the three-layer structure, a hole may be prevented from being made by the fire in the inner surfaces of the upper duct <NUM> and the lower duct <NUM>. Accordingly, the present disclosure may significantly increase the safety against a fire.

<FIG> is a schematic perspective view of a second insulating plate of a battery module, according to another embodiment of the present disclosure.

Referring to <FIG>, the first insulating plate <NUM> and the second insulating plate <NUM> of the battery module <NUM> according to another embodiment of the present disclosure may each further include a sealing member <NUM> when compared with the battery module <NUM> of <FIG>.

In detail, the sealing member <NUM> may be configured to expand in volume at a predetermined temperature or more to seal the upper duct <NUM> or the lower duct <NUM>. For example, the predetermined temperature may be <NUM> degrees Celsius or more. Also, the sealing member <NUM> may prevent a flame, smoke, and high-temperature gas from leaking out through the upper duct <NUM> or the lower duct <NUM>. Furthermore, the sealing member <NUM> may have heat insulating properties.

At least a portion of the sealing member <NUM> may be, for example, a material of the FS1000 available from Saint-Gobain. Alternatively, the sealing member <NUM> may include graphite flakes that expand in volume at a predetermined temperature. Also, when a central portion of the sealing member <NUM> is heated to <NUM> degrees Celsius or more, the central portion is carbonized to generate a carbonized layer in which volume expansion occurs.

Also, as shown in <FIG>, the sealing member <NUM> may be arranged on the second protection portion 133b of the second insulating plate <NUM>. Although not shown, the sealing member <NUM> may be arranged on the first protection portion 133a of the first insulating plate <NUM>.

Therefore, according to this configuration of the present disclosure, the present disclosure includes the sealing member <NUM> configured to expand in volume at a predetermined temperature or more for sealing, and thus, when a fire or thermal runaway occurs in the battery cell assembly <NUM>, the volume of the sealing member <NUM> expands due to high-temperature gas or air, and the volume-expanded sealing member <NUM> may seal the upper duct <NUM> or the lower duct <NUM> such that outside air may no longer be introduced into the module case <NUM>. Accordingly, the module case <NUM> sealed from the outside may prevent a fire of the battery cell assembly <NUM> from further spreading, and ultimately induce natural fire extinguishing.

Meanwhile, referring back to <FIG>, the first insulating plate <NUM> or the second insulating plate <NUM> of the present disclosure may each include a partition wall portion W. The partition wall portion W may have a shape bent toward the battery cell assembly <NUM> from an outer peripheral end portion. The partition wall portion W may have a shape extending along an outer peripheral portion of the first insulating plate <NUM> or the second insulating plate <NUM>. For example, as shown in <FIG>, the second insulating plate <NUM> may include the partition wall portion W extending along the outer periphery and protruding upward to a predetermined height.

Therefore, according to this configuration of the present disclosure, the first insulating plate <NUM> and the second insulating plate <NUM> of the present disclosure each includes the partition wall portion W, and thus, when dew condensation occurs inside the module case <NUM> due to a temperature difference between the outside and the inside of the module case <NUM> by the partition wall portion W, generated water may be accommodated in the first insulating plate <NUM> or the second insulating plate <NUM>. That is, the water accommodated in the inner surface of the first insulating plate <NUM> or the second insulating plate <NUM> may move to the outer periphery, and thus may be prevented from flowing into the upper plate <NUM> or the lower plate <NUM>. Accordingly, it is possible to effectively prevent the occurrence of an electric leakage, electric short circuit, or the like due to a dew condensation phenomenon of the battery module <NUM>.

<FIG> is a schematic perspective view showing a second insulating plate of a battery module, according to another embodiment of the present disclosure.

Referring to <FIG>, the second insulating plate <NUM> of the battery module <NUM> according to another embodiment of the present disclosure may further have an at least partially inclined surface 132c when compared with the second insulating plate <NUM> of <FIG>. For example, as shown in <FIG>, the second insulating plate <NUM> may have an inclined surface having a low center in the left-right direction and a gradually increasing height toward a left end portion and a right end portion. For example, the inclined surface may have an angle of <NUM> to <NUM> degrees with respect to the ground.

Therefore, according to this configuration of the present disclosure, the second insulating plate <NUM> of the present disclosure has the at least partially inclined surface 132c, and thus, when dew condensation occurs inside the module case <NUM> due to a temperature difference between the outside and the inside of the module case <NUM>, generated water may be accumulated in the center of the second insulating plate <NUM>. That is, the second insulating plate <NUM> may prevent the water accumulated in the inner surface from moving to the outer periphery and flowing into the upper plate <NUM> or the lower plate <NUM>. Accordingly, it is possible to effectively prevent the occurrence of an electric leakage, electric short circuit, or the like due to a dew condensation phenomenon of the battery module <NUM>.

Meanwhile, referring back to <FIG>, the second insulating plate <NUM> of the battery module <NUM> according to another embodiment of the present disclosure may further include a discharge port <NUM> when compared with the second insulating plate <NUM> of <FIG>. The discharge port <NUM> may be configured to discharge a fluid to the outside. For example, the second insulating plate <NUM> shown in <FIG> may be configured in such a manner that water flowing along the inclined surface 132c is discharged to the outside by the discharge port <NUM>. In this case, an opening T may be formed in a portion of a partition wall of the second insulating plate <NUM> to communicate with the discharge port <NUM>.

Therefore, according to this configuration of the present disclosure, the present disclosure includes the discharge port <NUM> in the second insulating plate <NUM>, and thus, when dew condensation occurs in the module case <NUM> due to a temperature difference between the outside and the inside of the module case <NUM>, generated water may be accumulated in the center of the second insulating plate <NUM> along the inclined surface 132c, and the water accumulated in the center thereof may be discharged to the outside through the discharge port <NUM> again. Accordingly, it is possible to effectively prevent the occurrence of an electric leakage, electric short circuit, or the like due to a dew condensation phenomenon of the battery module <NUM>.

Meanwhile, a battery rack (not shown) according to the present disclosure includes at least one battery module <NUM>. The battery rack may include a battery rack case for accommodating the battery module <NUM>. The battery rack may further include a battery management system (BMS) for performing charge and discharge control of a plurality of battery modules <NUM>.

A power storage device (not shown) according to the present disclosure includes at least one battery modules <NUM> according to the present disclosure. Especially, the power storage device may include a plurality of battery modules <NUM> according to the present disclosure. Also, the plurality of battery modules <NUM> may be electrically connected to each other. The power storage device according to the present disclosure may be implemented in various forms, such as a smart grid system or an electric charging station.

Meanwhile, although the terms indicating directions such as up, down, left, right, before, and after described in the present specification are used, it would be obvious to a person skilled in the art that the terms are only for convenience of description and may vary depending on the position of an object or the position of an observer.

As described above, although the present disclosure has been described according to limited embodiments and drawings, the present disclosure is not limited thereto, and the scope of patent protection is defined solely by the appended claims.

Claim 1:
A battery module (<NUM>) comprising:
a battery cell assembly (<NUM>) having a plurality of battery cells (<NUM>);
a front cover (<NUM>) comprising an upper wall (140a), a lower wall (140b), a left wall (140c), and a right wall (140d), which form an inner space;
a module case (<NUM>) accommodating the battery cell assembly (<NUM>) in the inner space, coupled to the front cover (<NUM>), and comprising a cover portion (<NUM>) that has a portion protruding to face at least one of the upper wall (140a), the lower wall (140b), the left wall (140c), and the right wall (140d),
wherein the cover portion (<NUM>) and the at least one of the upper wall (140a), the lower wall (140b), the left wall (140c), and the right wall (140d) of the front cover (<NUM>) form a double layer.